CINXE.COM

<!DOCTYPE html> <html lang="en" dir="ltr"> <head>  <script async src="https://www.googletagmanager.com/gtag/js?id=G-P63WKM1TM1"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-P63WKM1TM1'); </script>  <script type="text/javascript" > (function(m,e,t,r,i,k,a){m[i]=m[i]||function(){(m[i].a=m[i].a||[]).push(arguments)}; m[i].l=1*new Date(); for (var j = 0; j < document.scripts.length; j++) {if (document.scripts[j].src === r) { return; }} k=e.createElement(t),a=e.getElementsByTagName(t)[0],k.async=1,k.src=r,a.parentNode.insertBefore(k,a)}) (window, document, "script", "https://mc.yandex.ru/metrika/tag.js", "ym"); ym(55165297, "init", { clickmap:false, trackLinks:true, accurateTrackBounce:true, webvisor:false }); </script> <noscript><div><img src="https://mc.yandex.ru/watch/55165297" style="position:absolute; left:-9999px;" alt="" /></div></noscript>    <title>Search results for: conformation</title> <meta name="description" content="Search results for: conformation"> <meta name="keywords" content="conformation"> <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no"> <meta charset="utf-8"> <link href="https://cdn.waset.org/favicon.ico" type="image/x-icon" rel="shortcut icon"> <link href="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/css/bootstrap.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/plugins/fontawesome/css/all.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/css/site.css?v=150220211555" rel="stylesheet"> </head> <body> <header> <div class="container"> <nav class="navbar navbar-expand-lg navbar-light"> <a class="navbar-brand" href="https://waset.org"> <img src="https://cdn.waset.org/static/images/wasetc.png" alt="Open Science Research Excellence" title="Open Science Research Excellence" /> </a> <button class="d-block d-lg-none navbar-toggler ml-auto" type="button" data-toggle="collapse" data-target="#navbarMenu" aria-controls="navbarMenu" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button> <div class="w-100"> <div class="d-none d-lg-flex flex-row-reverse"> <form method="get" action="https://waset.org/search" class="form-inline my-2 my-lg-0"> <input class="form-control mr-sm-2" type="search" placeholder="Search Conferences" value="conformation" name="q" aria-label="Search"> <button class="btn btn-light my-2 my-sm-0" type="submit"><i class="fas fa-search"></i></button> </form> </div> <div class="collapse navbar-collapse mt-1" id="navbarMenu"> <ul class="navbar-nav ml-auto align-items-center" id="mainNavMenu"> <li class="nav-item"> <a class="nav-link" href="https://waset.org/conferences" title="Conferences in 2024/2025/2026">Conferences</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/disciplines" title="Disciplines">Disciplines</a> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/committees" rel="nofollow">Committees</a> </li> <li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdownPublications" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Publications </a> <div class="dropdown-menu" aria-labelledby="navbarDropdownPublications"> <a class="dropdown-item" href="https://publications.waset.org/abstracts">Abstracts</a> <a class="dropdown-item" href="https://publications.waset.org">Periodicals</a> <a class="dropdown-item" href="https://publications.waset.org/archive">Archive</a> </div> </li> <li class="nav-item"> <a class="nav-link" href="https://waset.org/page/support" title="Support">Support</a> </li> </ul> </div> </div> </nav> </div> </header> <main> <div class="container mt-4"> <div class="row"> <div class="col-md-9 mx-auto"> <form method="get" action="https://publications.waset.org/abstracts/search"> <div id="custom-search-input"> <div class="input-group"> <i class="fas fa-search"></i> <input type="text" class="search-query" name="q" placeholder="Author, Title, Abstract, Keywords" value="conformation"> <input type="submit" class="btn_search" value="Search"> </div> </div> </form> </div> </div> <div class="row mt-3"> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Commenced</strong> in January 2007</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Frequency:</strong> Monthly</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Edition:</strong> International</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Paper Count:</strong> 90</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: conformation</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">90</span> Effect of Formulation Compositions and Freezing Rates on the Conformational Changes of Influenza Virus Haemagglutinin (HA)</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Thanh%20Phuong%20Doan">Thanh Phuong Doan</a>, <a href="https://publications.waset.org/abstracts/search?q=Narueporn%20Sutanthavibul"> Narueporn Sutanthavibul</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The influence of freezing cycle on influenza haemagglutinin (HA) conformational stability was investigated in terms of freezing rates and formulation compositions. The results showed that appropriate HA conformation could be evaluated using circular dichroism (CD) spectroscopy with HA concentration of greater than 0.09 mg/ml. The intermediate freezing rate of approximately 1.0oC/min preserved the original HA conformation better than at slow freezing rate (0.5oC/min) and rapid freezing rate (2.6oC/min). The changes in CD spectra of the secondary HA structure were more pronounced than those of the tertiary HA structure during the evaluation. Additionally, the formulations, which resulted in the highest conformational stability were found to have sucrose present in the composition. As opposed to when only glycine was used, the stability of HA conformation was poor. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=freezing" title="freezing">freezing</a>, <a href="https://publications.waset.org/abstracts/search?q=haemagglutinin" title=" haemagglutinin"> haemagglutinin</a>, <a href="https://publications.waset.org/abstracts/search?q=influenza" title=" influenza"> influenza</a>, <a href="https://publications.waset.org/abstracts/search?q=circular%20dichroism" title=" circular dichroism"> circular dichroism</a> </p> <a href="https://publications.waset.org/abstracts/26789/effect-of-formulation-compositions-and-freezing-rates-on-the-conformational-changes-of-influenza-virus-haemagglutinin-ha" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/26789.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">395</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">89</span> Preferred Left-Handed Conformation of Glycyls at Pathogenic Sites</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Purva%20Mishra">Purva Mishra</a>, <a href="https://publications.waset.org/abstracts/search?q=Rajesh%20Potlia"> Rajesh Potlia</a>, <a href="https://publications.waset.org/abstracts/search?q=Kuljeet%20Singh%20Sandhu"> Kuljeet Singh Sandhu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The role of glycyl residues in the protein structure has lingered within the research community for the last several decades. Glycyl residue is the only amino acid that is achiral due to the lack of a side chain and can, therefore, exhibit Ramachandran conformations that are disallowed for L-amino acids. The structural and functional significance of glycyl residues with L-disallowed conformation, however, remains obscure. Through statistical analysis of various datasets, we found that the glycyls with L-disallowed conformations are over-represented at disease-associated sites and tend to be evolutionarily conserved. The mutations of L-disallowed glycyls tend to destabilize the native conformation, reduce protein solubility, and promote inter-molecular aggregations. We uncovered a structural motif referred to as “β-crescent” formed around the L-disallowed glycyl, which prevents β-sheet aggregation by disrupting the alternating pattern of β-pleats. The L-disallowed conformation of glycyls also holds predictive power to infer the pathogenic missense variants. Altogether, our observations highlight that the L-disallowed conformation of glycyls is selected to facilitate native folding and prevent inter-molecular aggregations. The findings may also have implications for designing more stable proteins and prioritizing the genetic lesions implicated in diseases. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ramachandran%20plot" title="Ramachandran plot">Ramachandran plot</a>, <a href="https://publications.waset.org/abstracts/search?q=%CE%B2-sheet" title=" β-sheet"> β-sheet</a>, <a href="https://publications.waset.org/abstracts/search?q=protein%20stability" title=" protein stability"> protein stability</a>, <a href="https://publications.waset.org/abstracts/search?q=protein%20aggregation" title=" protein aggregation"> protein aggregation</a> </p> <a href="https://publications.waset.org/abstracts/179122/preferred-left-handed-conformation-of-glycyls-at-pathogenic-sites" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/179122.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">72</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">88</span> Single-Molecule Analysis of Structure and Dynamics in Polymer Materials by Super-Resolution Technique</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hiroyuki%20Aoki">Hiroyuki Aoki</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The physical properties of polymer materials are dependent on the conformation and molecular motion of a polymer chain. Therefore, the structure and dynamic behavior of the single polymer chain have been the most important concerns in the field of polymer physics. However, it has been impossible to directly observe the conformation of the single polymer chain in a bulk medium. In the current work, the novel techniques to study the conformation and dynamics of a single polymer chain are proposed. Since a fluorescence method is extremely sensitive, the fluorescence microscopy enables the direct detection of a single molecule. However, the structure of the polymer chain as large as 100 nm cannot be resolved by conventional fluorescence methods because of the diffraction limit of light. In order to observe the single chains, we developed the labeling method of polymer materials with a photo-switchable dye and the super-resolution microscopy. The real-space conformational analysis of single polymer chains with the spatial resolution of 15-20 nm was achieved. The super-resolution microscopy enables us to obtain the three-dimensional coordinates; therefore, we succeeded the conformational analysis in three dimensions. The direct observation by the nanometric optical microscopy would reveal the detailed information on the molecular processes in the various polymer systems. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=polymer%20materials" title="polymer materials">polymer materials</a>, <a href="https://publications.waset.org/abstracts/search?q=single%20molecule" title=" single molecule"> single molecule</a>, <a href="https://publications.waset.org/abstracts/search?q=super-resolution%20techniques" title=" super-resolution techniques"> super-resolution techniques</a>, <a href="https://publications.waset.org/abstracts/search?q=conformation" title=" conformation"> conformation</a> </p> <a href="https://publications.waset.org/abstracts/57901/single-molecule-analysis-of-structure-and-dynamics-in-polymer-materials-by-super-resolution-technique" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/57901.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">305</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">87</span> Structural Analysis of Polymer Thin Films at Single Macromolecule Level</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hiroyuki%20Aoki">Hiroyuki Aoki</a>, <a href="https://publications.waset.org/abstracts/search?q=Toru%20Asada"> Toru Asada</a>, <a href="https://publications.waset.org/abstracts/search?q=Tomomi%20Tanii"> Tomomi Tanii</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The properties of a spin-cast film of a polymer material are different from those in the bulk material because the polymer chains are frozen in an un-equilibrium state due to the rapid evaporation of the solvent. However, there has been little information on the un-equilibrated conformation and dynamics in a spin-cast film at the single chain level. The real-space observation of individual chains would provide direct information to discuss the morphology and dynamics of single polymer chains. The recent development of super-resolution fluorescence microscopy methods allows the conformational analysis of single polymer chain. In the current study, the conformation of a polymer chain in a spin-cast film by the super-resolution microscopy. Poly(methyl methacrylate) (PMMA) with the molecular weight of 2.2 x 10^6 was spin-cast onto a glass substrate from toluene and chloroform. For the super-resolution fluorescence imaging, a small amount of the PMMA labeled by rhodamine spiroamide dye was added. The radius of gyration (Rg) was evaluated from the super-resolution fluorescence image of each PMMA chain. The mean-square-root of Rg was 48.7 and 54.0 nm in the spin-cast films prepared from the toluene and chloroform solutions, respectively. On the other hand, the chain dimension in a bulk state (a thermally annealed 10- μm-thick sample) was observed to be 43.1 nm. This indicates that the PMMA chain in the spin-cast film takes an expanded conformation compared to the unperturbed chain and that the chain dimension is dependent on the solvent quality. In a good solvent, the PMMA chain has an expanded conformation by the excluded volume effect. The polymer chain is frozen before the relaxation from an un-equilibrated expanded conformation to an unperturbed one by the rapid solvent evaporation. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=chain%20conformation" title="chain conformation">chain conformation</a>, <a href="https://publications.waset.org/abstracts/search?q=polymer%20thin%20film" title=" polymer thin film"> polymer thin film</a>, <a href="https://publications.waset.org/abstracts/search?q=spin-coating" title=" spin-coating"> spin-coating</a>, <a href="https://publications.waset.org/abstracts/search?q=super-resolution%20optical%20microscopy" title=" super-resolution optical microscopy"> super-resolution optical microscopy</a> </p> <a href="https://publications.waset.org/abstracts/41961/structural-analysis-of-polymer-thin-films-at-single-macromolecule-level" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/41961.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">287</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">86</span> Principal Component Analysis of Body Weight and Morphometric Traits of New Zealand Rabbits Raised under Semi-Arid Condition in Nigeria</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Emmanuel%20Abayomi%20Rotimi">Emmanuel Abayomi Rotimi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Context: Rabbits production plays important role in increasing animal protein supply in Nigeria. Rabbit production provides a cheap, affordable, and healthy source of meat. The growth of animals involves an increase in body weight, which can change the conformation of various parts of the body. Live weight and linear measurements are indicators of growth rate in rabbits and other farm animals. Aims: This study aimed to define the body dimensions of New Zealand rabbits and also to investigate the morphometric traits variables that contribute to body conformation by the use of principal component analysis (PCA). Methods: Data were obtained from 80 New Zealand rabbits (40 bucks and 40 does) raised in Livestock Teaching and Research Farm, Federal University Dutsinma. Data were taken on body weight (BWT), body length (BL), ear length (EL), tail length (TL), heart girth (HG) and abdominal circumference (AC). Data collected were subjected to multivariate analysis using SPSS 20.0 statistical package. Key results: The descriptive statistics showed that the mean BWT, BL, EL, TL, HG, and AC were 0.91kg, 27.34cm, 10.24cm, 8.35cm, 19.55cm and 21.30cm respectively. Sex showed significant (P<0.05) effect on all the variables examined, with higher values recorded for does. The phenotypic correlation coefficient values (r) between the morphometric traits were all positive and ranged from r = 0.406 (between EL and BL) to r = 0.909 (between AC and HG). HG is the most correlated with BWT (r = 0.786). The principal component analysis with variance maximizing orthogonal rotation was used to extract the components. Two principal components (PCs) from the factor analysis of morphometric traits explained about 80.42% of the total variance. PC1 accounted for 64.46% while PC2 accounted for 15.97% of the total variances. Three variables, representing body conformation, loaded highest in PC1. PC1 had the highest contribution (64.46%) to the total variance, and it is regarded as body conformation traits. Conclusions: This component could be used as selection criteria for improving body weight of rabbits. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=conformation" title="conformation">conformation</a>, <a href="https://publications.waset.org/abstracts/search?q=multicollinearity" title=" multicollinearity"> multicollinearity</a>, <a href="https://publications.waset.org/abstracts/search?q=multivariate" title=" multivariate"> multivariate</a>, <a href="https://publications.waset.org/abstracts/search?q=rabbits%20and%20principal%20component%20analysis" title=" rabbits and principal component analysis"> rabbits and principal component analysis</a> </p> <a href="https://publications.waset.org/abstracts/110184/principal-component-analysis-of-body-weight-and-morphometric-traits-of-new-zealand-rabbits-raised-under-semi-arid-condition-in-nigeria" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/110184.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">130</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">85</span> Quantitative Detection of the Conformational Transitions between Open and Closed Forms of Cytochrome P450 Oxidoreductase (CYPOR) at the Membrane Surface in Different Functional States</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sara%20Arafeh">Sara Arafeh</a>, <a href="https://publications.waset.org/abstracts/search?q=Kovriguine%20Evguine"> Kovriguine Evguine</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Cytochromes P450 are enzymes that require a supply of electrons to catalyze the synthesis of steroid hormones, fatty acids, and prostaglandin hormone. Cytochrome P450 Oxidoreductase (CYPOR), a membrane bound enzyme, provides these electrons in its open conformation. CYPOR has two cytosolic domains (FAD domain and FMN domain) and an N-terminal in the membrane. In its open conformation, electrons flow from NADPH, FAD, and finally to FMN where cytochrome P450 picks up these electrons. In the closed conformation, cytochrome P450 does not bind to the FMN domain to take the electrons. It was found that when the cytosolic domains are isolated, CYPOR could not bind to cytochrome P450. This suggested that the membrane environment is important for CYPOR function. This project takes the initiative to better understand the dynamics of CYPOR in its full length. Here, we determine the distance between specific sites in the FAD and FMN binding domains in CYPOR by Forster Resonance Energy Transfer (FRET) and Ultrafast TA spectroscopy with and without NADPH. The approach to determine these distances will rely on labeling these sites with red and infrared fluorophores. Mimic membrane attachment is done by inserting CYPOR in lipid nanodiscs. By determining the distances between the donor-acceptor sites in these domains, we can observe the open/closed conformations upon reducing CYPOR in the presence and absence of cytochrome P450. Such study is important to better understand CYPOR mechanism of action in various endosomal membranes including hepatic CYPOR which is vital in plasma cholesterol homeostasis. By investigating the conformational cycles of CYPOR, we can synthesize drugs that would be more efficient in affecting the steroid hormonal levels and metabolism of toxins catalyzed by Cytochrome P450. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=conformational%20cycle%20of%20CYPOR" title="conformational cycle of CYPOR">conformational cycle of CYPOR</a>, <a href="https://publications.waset.org/abstracts/search?q=cytochrome%20P450" title=" cytochrome P450"> cytochrome P450</a>, <a href="https://publications.waset.org/abstracts/search?q=cytochrome%20P450%20oxidoreductase" title=" cytochrome P450 oxidoreductase"> cytochrome P450 oxidoreductase</a>, <a href="https://publications.waset.org/abstracts/search?q=FAD%20domain" title=" FAD domain"> FAD domain</a>, <a href="https://publications.waset.org/abstracts/search?q=FMN%20domain" title=" FMN domain"> FMN domain</a>, <a href="https://publications.waset.org/abstracts/search?q=FRET" title=" FRET"> FRET</a>, <a href="https://publications.waset.org/abstracts/search?q=Ultrafast%20TA%20Spectroscopy" title=" Ultrafast TA Spectroscopy"> Ultrafast TA Spectroscopy</a> </p> <a href="https://publications.waset.org/abstracts/63085/quantitative-detection-of-the-conformational-transitions-between-open-and-closed-forms-of-cytochrome-p450-oxidoreductase-cypor-at-the-membrane-surface-in-different-functional-states" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/63085.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">279</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">84</span> The Actuation of Semicrystalline Poly(Vinylidene Fluoride) Tie Molecules: A Computational and Experimental Study</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abas%20Mohsenzadeh">Abas Mohsenzadeh</a>, <a href="https://publications.waset.org/abstracts/search?q=Tariq%20Bashir"> Tariq Bashir</a>, <a href="https://publications.waset.org/abstracts/search?q=Waseen%20Tahir"> Waseen Tahir</a>, <a href="https://publications.waset.org/abstracts/search?q=Ulf%20Stigh"> Ulf Stigh</a>, <a href="https://publications.waset.org/abstracts/search?q=Mikael%20Skrifvars"> Mikael Skrifvars</a>, <a href="https://publications.waset.org/abstracts/search?q=Kim%20Bolton"> Kim Bolton</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The area of artificial muscles has received significant attention from many research domains including soft robotics, biomechanics and smart textiles in recent years. Poly(vinylidene fluoride) (PVDF) has been used to form artificial muscles since it contracts upon heating when under load. In this study, PVDF fibers were produced by melt spinning technique at different solid state draw ratios and then actuation mechanism for PVDF tie molecules within the semicrystalline region of PVDF polymer has been investigated using molecular dynamics simulations. Tie molecules are polymer chains that link two (or more) crystalline regions in semicrystalline polymers. The changes in fiber length upon heating have been investigated using a novel simulation technique. The results show that conformational changes of the tie molecules from the longer all-trans conformation at low temperature (β structure) to the shorter conformation (α structure) at higher temperature accrue by increasing the temperature. These results may be applied to understand the actuation observed for PVDF upon heating. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=poly%28vinylidene%20fluoride%29" title="poly(vinylidene fluoride)">poly(vinylidene fluoride)</a>, <a href="https://publications.waset.org/abstracts/search?q=molecular%20dynamics" title=" molecular dynamics"> molecular dynamics</a>, <a href="https://publications.waset.org/abstracts/search?q=simulation" title=" simulation"> simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=actuators" title=" actuators"> actuators</a>, <a href="https://publications.waset.org/abstracts/search?q=tie%20molecules" title=" tie molecules"> tie molecules</a>, <a href="https://publications.waset.org/abstracts/search?q=semicrystalline" title=" semicrystalline"> semicrystalline</a> </p> <a href="https://publications.waset.org/abstracts/77139/the-actuation-of-semicrystalline-polyvinylidene-fluoride-tie-molecules-a-computational-and-experimental-study" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/77139.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">308</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">83</span> Modeling of Anode Catalyst against CO in Fuel Cell Using Material Informatics</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Khorshed%20Alam">M. Khorshed Alam</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20Takaba"> H. Takaba</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The catalytic properties of metal usually change by intermixturing with another metal in polymer electrolyte fuel cells. Pt-Ru alloy is one of the much-talked used alloy to enhance the CO oxidation. In this work, we have investigated the CO coverage on the Pt2Ru3 nanoparticle with different atomic conformation of Pt and Ru using a combination of material informatics with computational chemistry. Density functional theory (DFT) calculations used to describe the adsorption strength of CO and H with different conformation of Pt Ru ratio in the Pt2Ru3 slab surface. Then through the Monte Carlo (MC) simulations we examined the segregation behaviour of Pt as a function of surface atom ratio, subsurface atom ratio, particle size of the Pt2Ru3 nanoparticle. We have constructed a regression equation so as to reproduce the results of DFT only from the structural descriptors. Descriptors were selected for the regression equation; xa-b indicates the number of bonds between targeted atom a and neighboring atom b in the same layer (a,b = Pt or Ru). Terms of xa-H2 and xa-CO represent the number of atoms a binding H2 and CO molecules, respectively. xa-S is the number of atom a on the surface. xa-b- is the number of bonds between atom a and neighboring atom b located outside the layer. The surface segregation in the alloying nanoparticles is influenced by their component elements, composition, crystal lattice, shape, size, nature of the adsorbents and its pressure, temperature etc. Simulations were performed on different size (2.0 nm, 3.0 nm) of nanoparticle that were mixing of Pt and Ru atoms in different conformation considering of temperature range 333K. In addition to the Pt2Ru3 alloy we also considered pure Pt and Ru nanoparticle to make comparison of surface coverage by adsorbates (H2, CO). Hence, we assumed the pure and Pt-Ru alloy nanoparticles have an fcc crystal structures as well as a cubo-octahedron shape, which is bounded by (111) and (100) facets. Simulations were performed up to 50 million MC steps. From the results of MC, in the presence of gases (H2, CO), the surfaces are occupied by the gas molecules. In the equilibrium structure the coverage of H and CO as a function of the nature of surface atoms. In the initial structure, the Pt/Ru ratios on the surfaces for different cluster sizes were in range of 0.50 - 0.95. MC simulation was employed when the partial pressure of H2 (PH2) and CO (PCO) were 70 kPa and 100-500 ppm, respectively. The Pt/Ru ratios decrease as the increase in the CO concentration, without little exception only for small nanoparticle. The adsorption strength of CO on the Ru site is higher than the Pt site that would be one of the reason for decreasing the Pt/Ru ratio on the surface. Therefore, our study identifies that controlling the nanoparticle size, composition, conformation of alloying atoms, concentration and chemical potential of adsorbates have impact on the steadiness of nanoparticle alloys which ultimately and also overall catalytic performance during the operations. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=anode%20catalysts" title="anode catalysts">anode catalysts</a>, <a href="https://publications.waset.org/abstracts/search?q=fuel%20cells" title=" fuel cells"> fuel cells</a>, <a href="https://publications.waset.org/abstracts/search?q=material%20informatics" title=" material informatics"> material informatics</a>, <a href="https://publications.waset.org/abstracts/search?q=Monte%20Carlo" title=" Monte Carlo"> Monte Carlo</a> </p> <a href="https://publications.waset.org/abstracts/80312/modeling-of-anode-catalyst-against-co-in-fuel-cell-using-material-informatics" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/80312.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">192</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">82</span> Conformation Prediction of Human Plasmin and Docking on Gold Nanoparticle</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Wen-Shyong%20Tzou">Wen-Shyong Tzou</a>, <a href="https://publications.waset.org/abstracts/search?q=Chih-Ching%20Huang"> Chih-Ching Huang</a>, <a href="https://publications.waset.org/abstracts/search?q=Chin-Hwa%20Hu"> Chin-Hwa Hu</a>, <a href="https://publications.waset.org/abstracts/search?q=Ying-Tsang%20Lo"> Ying-Tsang Lo</a>, <a href="https://publications.waset.org/abstracts/search?q=Tun-Wen%20Pai"> Tun-Wen Pai</a>, <a href="https://publications.waset.org/abstracts/search?q=Chia-Yin%20Chiang"> Chia-Yin Chiang</a>, <a href="https://publications.waset.org/abstracts/search?q=Chung-Hao%20Li"> Chung-Hao Li</a>, <a href="https://publications.waset.org/abstracts/search?q=Hong-Jyuan%20Jian"> Hong-Jyuan Jian</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Plasmin plays an important role in the human circulatory system owing to its catalytic ability of fibrinolysis. The immediate injection of plasmin in patients of strokes has intrigued many scientists to design vectors that can transport plasmin to the desired location in human body. Here we predict the structure of human plasmin and investigate the interaction of plasmin with the gold-nanoparticle. Because the crystal structure of plasminogen has been solved, we deleted N-terminal domain (Pan-apple domain) of plasminogen and generate a mimic of the active form of this enzyme (plasmin). We conducted a simulated annealing process on plasmin and discovered a very large conformation occurs. Kringle domains 1, 4 and 5 had been observed to leave its original location relative to the main body of the enzyme and the original doughnut shape of this enzyme has been transformed to a V-shaped by opening its two arms. This observation of conformational change is consistent with the experimental results of neutron scattering and centrifugation. We subsequently docked the plasmin on the simulated gold surface to predict their interaction. The V-shaped plasmin could utilize its Kringle domain and catalytic domain to contact the gold surface. Our findings not only reveal the flexibility of plasmin structure but also provide a guide for the design of a plasmin-gold nanoparticle. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=docking" title="docking">docking</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20nanoparticle" title=" gold nanoparticle"> gold nanoparticle</a>, <a href="https://publications.waset.org/abstracts/search?q=molecular%20simulation" title=" molecular simulation"> molecular simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=plasmin" title=" plasmin"> plasmin</a> </p> <a href="https://publications.waset.org/abstracts/21993/conformation-prediction-of-human-plasmin-and-docking-on-gold-nanoparticle" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/21993.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">472</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">81</span> Effect of Spirulina Supplementation on Growth Performance and Body Conformation of Two Omani Goat Breeds </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Fahad%20Al%20Yahyaey">Fahad Al Yahyaey</a>, <a href="https://publications.waset.org/abstracts/search?q=Ihab%20Shaat"> Ihab Shaat</a>, <a href="https://publications.waset.org/abstracts/search?q=Russell%20Bush"> Russell Bush </a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study was conducted at the Livestock Research Centre, Ministry of Agriculture and Fisheries, Oman, on two local goat breeds (Jabbali and Sahrawi) due to their importance to Omani livestock production and food security. The Jabbali is characterized by increased growth rates and a higher twinning rate, while the Sahrawi has increased milk production. The aim of the study was to investigate the effect of Spirulina supplementation on live weight (BWT), average daily gain (ADG), and body conformation measurements; chest girth (CG), wither height (WH), body length (BL), and body condition score (BCS). Thirty-six males (approximately nine-months-old and 16.44 ± 0.33 kg average of initial body weight) were used across an eleven-week study from November–February 2019-2020. Each breed was divided into three groups (n = 6/group) and fed one of three rations: (1) concentrate mixture (Control) with crude protein 14% and energy 11.97% MJ/kg DM; (2) the same concentrate feed with the addition of 2 gm /capita daily Spirulina platensis (Treatment 1) and (3) the same concentrate feed with the addition of 4 gm /capita daily Spirulina platensis (Treatment 2). Analysis of weekly data collections for all traits indicated a significant effect of feeding Spirulina on all the studied traits except WH and BL. Analysis of variance for fixed effects in this study (damage and kid birth type i.e., single, twin or triple) were not significant for all studied traits. However, the breed effect was highly significant (P < 0.001) on BWT, ADG, BCS, and CG traits. On the other hand, when the analysis was done for the treatment effect within breeds for ADG, the Sahrawi breed had a significant effect (P < 0.05) at 56.52, 85.51, and 85.50 g/day for control, treatment 1 and treatment 2, respectively. This is a 51% difference between the control and treatment 1 (2 gm /capita). Whereas for the Jabbali breed, the treatment effect was not significant for ADG (P =0.55), and the actual ADG was 104.59, 118.84, and 114.25 g/day for control, treatment 1, and treatment 2, respectively, providing a 14% difference between the control group and the treated group (4 gm /capita). These findings indicate using Spirulina supplementation in Omani goat diets is recommended at 2 gm per capita as there was no benefit in feeding at 4 gm per capita for either breed. Farmers feeding Spirulina supplementation to kids after weaning at six-months could increase their herd performance and growth rate and facilitate buck selection at an earlier age. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=body%20conformation" title="body conformation">body conformation</a>, <a href="https://publications.waset.org/abstracts/search?q=goats" title=" goats"> goats</a>, <a href="https://publications.waset.org/abstracts/search?q=live%20weight" title=" live weight"> live weight</a>, <a href="https://publications.waset.org/abstracts/search?q=spirulina" title=" spirulina"> spirulina</a> </p> <a href="https://publications.waset.org/abstracts/129905/effect-of-spirulina-supplementation-on-growth-performance-and-body-conformation-of-two-omani-goat-breeds" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/129905.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">111</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">80</span> Binding Studies and Structure Determination of the Recombinantly Produced Type-II 3-Dehydroquinate Dehydratase from Acinetobacter Baumannii </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Naseer%20Iqbal">Naseer Iqbal</a>, <a href="https://publications.waset.org/abstracts/search?q=Mukesh%20Kumar"> Mukesh Kumar</a>, <a href="https://publications.waset.org/abstracts/search?q=Pradeep%20Sharma"> Pradeep Sharma</a>, <a href="https://publications.waset.org/abstracts/search?q=Satya%20Prakash%20Yadav"> Satya Prakash Yadav</a>, <a href="https://publications.waset.org/abstracts/search?q=Punit%20Kaur"> Punit Kaur</a>, <a href="https://publications.waset.org/abstracts/search?q=Sujata%20%20Sharma"> Sujata Sharma</a>, <a href="https://publications.waset.org/abstracts/search?q=T.%20P.%20Singh"> T. P. Singh</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Dehydroquinase (3-dehydroquinate dehydratase, DHQD, EC 4.2.1.10) is involved in shikimate pathway and catalyzes the conversion of dehydroquinate to dehydroshikimate. Shikimate pathway is important drug target as this pathway is absent in mammals. DHQD from Acinetobacter baumannii (AbDHQD) was cloned, expressed and purified to homogeneity. The binding studies showed that compounds quinic acid and citrazinic acid bound to AbDHQD at micromolar concentrations. AbDHQD was crystallized using 30% PEG-3350, 50mM tris-HCl, and 1.0M MgSO4 at PH 8.0. Crystals of AbDHQD were stabilized by transferring them into reservoir solution to which 25% glycerol was added for data collection at 100K. The X-ray intensity data were collected to 2.0Å resolution. The crystals belong to monoclinic space group P21 with cell dimensions, a = 82.3, b = 95.3, c = 132.3Å and β = 95.7°. The structure was solved with molecular replacement method and refined to Rcryst/Rfree factors of 0.200/0.232. The structures of 12 crystallographically independent molecules in the asymmetry unit were identical with r.m.s shifts for the C atoms ranging from 0.3 Å to 0.8 Å. They formed a dodecamer with four trimers arranged in a tetrahedral manner. The classical lid adopted an open conformation although a sulfate ion was observed in the substrate binding site. As a result of which, the compounds quinic acid and citrazinic acid did not bind to AbDHQD. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acinetobacter%20Bauman%20Nii" title="acinetobacter Bauman Nii">acinetobacter Bauman Nii</a>, <a href="https://publications.waset.org/abstracts/search?q=dehydroquinate%20dehydratase" title=" dehydroquinate dehydratase"> dehydroquinate dehydratase</a>, <a href="https://publications.waset.org/abstracts/search?q=dodecamer" title=" dodecamer"> dodecamer</a>, <a href="https://publications.waset.org/abstracts/search?q=open%20conformation" title=" open conformation"> open conformation</a> </p> <a href="https://publications.waset.org/abstracts/60811/binding-studies-and-structure-determination-of-the-recombinantly-produced-type-ii-3-dehydroquinate-dehydratase-from-acinetobacter-baumannii" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/60811.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">361</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">79</span> Enhanced Stability of Piezoelectric Crystalline Phase of Poly(Vinylidene Fluoride) (PVDF) and Its Copolymer upon Epitaxial Relationships</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Devi%20Eka%20Septiyani%20Arifin">Devi Eka Septiyani Arifin</a>, <a href="https://publications.waset.org/abstracts/search?q=Jrjeng%20Ruan"> Jrjeng Ruan</a> </p> <p class="card-text"><strong>Abstract:</strong></p> As an approach to manipulate the performance of polymer thin film, epitaxy crystallization within polymer blends of poly(vinylidene fluoride) (PVDF) and its copolymer poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) was studied in this research, which involves the competition between phase separation and crystal growth of constitutive semicrystalline polymers. The unique piezoelectric feature of poly(vinylidene fluoride) crystalline phase is derived from the packing of molecular chains in all-trans conformation, which spatially arranges all the substituted fluorene atoms on one side of the molecular chain and hydrogen atoms on the other side. Therefore, the net dipole moment is induced across the lateral packing of molecular chains. Nevertheless, due to the mutual repulsion among fluorene atoms, this all-trans molecular conformation is not stable, and ready to change above curie temperature, where thermal energy is sufficient to cause segmental rotation. This research attempts to explore whether the epitaxial interactions between piezoelectric crystals and crystal lattice of hexamethylbenzene (HMB) crystalline platelet is able to stabilize this metastable all-trans molecular conformation or not. As an aromatic crystalline compound, the melt of HMB was surprisingly found able to dissolve the poly(vinylidene fluoride), resulting in homogeneous eutectic solution. Thus, after quenching this binary eutectic mixture to room temperature, subsequent heating or annealing processes were designed to explore the involve phase separation and crystallization behavior. The phase transition behaviors were observed in-situ by X-ray diffraction and differential scanning calorimetry (DSC). The molecular packing was observed via transmission electron microscope (TEM) and the principles of electron diffraction were brought to study the internal crystal structure epitaxially developed within thin films. Obtained results clearly indicated the occurrence of heteroepitaxy of PVDF/PVDF-TrFE on HMB crystalline platelet. Both the concentration of poly(vinylidene fluoride) and the mixing ratios of these two constitutive polymers have been adopted as the influential factors for studying the competition between the epitaxial crystallization of PVDF and P(VDF-TrFE) on HMB crystalline. Furthermore, the involved epitaxial relationship is to be deciphered and studied as a potential factor capable of guiding the wide spread of piezoelectric crystalline form. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=epitaxy" title="epitaxy">epitaxy</a>, <a href="https://publications.waset.org/abstracts/search?q=crystallization" title=" crystallization"> crystallization</a>, <a href="https://publications.waset.org/abstracts/search?q=crystalline%20platelet" title=" crystalline platelet"> crystalline platelet</a>, <a href="https://publications.waset.org/abstracts/search?q=thin%20film%20and%20mixing%20ratio" title=" thin film and mixing ratio"> thin film and mixing ratio</a> </p> <a href="https://publications.waset.org/abstracts/46158/enhanced-stability-of-piezoelectric-crystalline-phase-of-polyvinylidene-fluoride-pvdf-and-its-copolymer-upon-epitaxial-relationships" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/46158.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">223</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">78</span> Molecular Dynamics Study of Ferrocene in Low and Room Temperatures</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Feng%20Wang">Feng Wang</a>, <a href="https://publications.waset.org/abstracts/search?q=Vladislav%20Vasilyev"> Vladislav Vasilyev</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Ferrocene (Fe(C5H5)2, i.e., di-cyclopentadienyle iron (FeCp2) or Fc) is a unique example of ‘wrong but seminal’ in chemistry history. It has significant applications in a number of areas such as homogeneous catalysis, polymer chemistry, molecular sensing, and nonlinear optical materials. However, the ‘molecular carousel’ has been a ‘notoriously difficult example’ and subject to long debate for its conformation and properties. Ferrocene is a dynamic molecule. As a result, understanding of the dynamical properties of ferrocene is very important to understand the conformational properties of Fc. In the present study, molecular dynamic (MD) simulations are performed. In the simulation, we use 5 geometrical parameters to define the overall conformation of Fc and all the rest is a thermal noise. The five parameters are defined as: three parameters d---the distance between two Cp planes, α and δ to define the relative positions of the Cp planes, in which α is the angle of the Cp tilt and δ the angle the two Cp plane rotation like a carousel. Two parameters to position the Fe atom between two Cps, i.e., d1 for Fe-Cp1 and d2 for Fe-Cp2 distances. Our preliminary MD simulation discovered the five parameters behave differently. Distances of Fe to the Cp planes show that they are independent, practically identical without correlation. The relative position of two Cp rings, α, indicates that the two Cp planes are most likely not in a parallel position, rather, they tilt in a small angle α≠ 0°. The mean plane dihedral angle δ ≠ 0°. Moreover, δ is neither 0° nor 36°, indicating under those conditions, Fc is neither in a perfect eclipsed structure nor a perfect staggered structure. The simulations show that when the temperature is above 80K, the conformers are virtually in free rotations, A very interesting result from the MD simulation is the five C-Fe bond distances from the same Cp ring. They are surprisingly not identical but in three groups of 2, 2 and 1. We describe the pentagon formed by five carbon atoms as ‘turtle swimming’ for the motion of the Cp rings of Fc as shown in their dynamical animation video. The Fe- C(1) and Fe-C(2) which are identical as ‘the turtle back legs’, Fe-C(3) and Fe-C(4) which are also identical as turtle front paws’, and Fe-C(5) ---’the turtle head’. Such as ‘turtle swimming’ analog may be able to explain the single substituted derivatives of Fc. Again, the mean Fe-C distance obtained from MD simulation is larger than the quantum mechanically calculated Fe-C distances for eclipsed and staggered Fc, with larger deviation with respect to the eclipsed Fc than the staggered Fc. The same trend is obtained for the five Fe-C-H angles from same Cp ring of Fc. The simulated mean IR spectrum at 7K shows split spectral peaks at approximately 470 cm-1 and 488 cm-1, in excellent agreement with quantum mechanically calculated gas phase IR spectrum for eclipsed Fc. As the temperature increases over 80K, the clearly splitting IR spectrum become a very board single peak. Preliminary MD results will be presented. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ferrocene%20conformation" title="ferrocene conformation">ferrocene conformation</a>, <a href="https://publications.waset.org/abstracts/search?q=molecular%20dynamics%20simulation" title=" molecular dynamics simulation"> molecular dynamics simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=conformer%20orientation" title=" conformer orientation"> conformer orientation</a>, <a href="https://publications.waset.org/abstracts/search?q=eclipsed%20and%20staggered%20ferrocene" title=" eclipsed and staggered ferrocene"> eclipsed and staggered ferrocene</a> </p> <a href="https://publications.waset.org/abstracts/55169/molecular-dynamics-study-of-ferrocene-in-low-and-room-temperatures" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/55169.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">218</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">77</span> Synthesis, Characterization and Catecholase Study of Novel Bidentate Schiff Base Derived from Dehydroacetic Acid</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Salima%20Tabti">Salima Tabti</a>, <a href="https://publications.waset.org/abstracts/search?q=Chaima%20Maouche"> Chaima Maouche</a>, <a href="https://publications.waset.org/abstracts/search?q=Tinhinene%20Louaileche"> Tinhinene Louaileche</a>, <a href="https://publications.waset.org/abstracts/search?q=Amel%20Djedouani"> Amel Djedouani</a>, <a href="https://publications.waset.org/abstracts/search?q=Ismail%20Warad"> Ismail Warad</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Novel Schiff base ligand HL has been synthesized by condensation of aromatic amine and DHA. It was characterized by UV-Vis, FT-IR, SM, NMR (1H, 13C) and also by single-crystal X-ray diffraction. The crystal structure shows that compound crystallized in a triclinic system in P-1 space group and with a two unit per cell (Z = 2).The asymmetric unit, contains one independent molecules, the conformation is determined by an intermolecular N-H…O hydrogen bond with an S(6) ring motif. The molecule have an (E) conformation about the C=N bond. The dihedral angles between the phenyl and pyran ring planes is 89.37 (1), the two plans are approximately perpendicular. The catecholase activity of is situ copper complexes of this ligand has been investigated against catechol. The progress of the oxidation reactions was closely monitored over time following the strong peak of catechol using UV-Vis. Oxidation rates were determined from the initial slope of absorbance. time plots, then analyzed by Michaelis-Menten equations. Catechol oxidation reactions were realized using different concentrations of copper acetate and ligand (L/Cu: 1/1, 1/2, 2/1). The results show that all complexes were able to catalyze the oxidation of catechol. Acetate complexes have the highest activity. Catalysis is a branch of chemical kinetics that, more generally, studies the influence of all physical or chemical factors determining reaction rates. It solves a lot of problems in the chemistry reaction process, especially for a green, economic and less polluting chemistry. For this reason, the search for new catalysts for known organic reactions, occupies a very advanced place in the themes proposed by the chemists. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=dehydroacetic%20acid" title="dehydroacetic acid">dehydroacetic acid</a>, <a href="https://publications.waset.org/abstracts/search?q=catechol" title=" catechol"> catechol</a>, <a href="https://publications.waset.org/abstracts/search?q=copper" title=" copper"> copper</a>, <a href="https://publications.waset.org/abstracts/search?q=catecholase%20activity" title=" catecholase activity"> catecholase activity</a>, <a href="https://publications.waset.org/abstracts/search?q=x-ray" title=" x-ray"> x-ray</a> </p> <a href="https://publications.waset.org/abstracts/167958/synthesis-characterization-and-catecholase-study-of-novel-bidentate-schiff-base-derived-from-dehydroacetic-acid" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/167958.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">110</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">76</span> Process Development of pVAX1/lacZ Plasmid DNA Purification Using Design of Experiment</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Asavasereerat%20K.">Asavasereerat K.</a>, <a href="https://publications.waset.org/abstracts/search?q=Teacharsripaitoon%20T."> Teacharsripaitoon T.</a>, <a href="https://publications.waset.org/abstracts/search?q=Tungyingyong%20P."> Tungyingyong P.</a>, <a href="https://publications.waset.org/abstracts/search?q=Charupongrat%20S."> Charupongrat S.</a>, <a href="https://publications.waset.org/abstracts/search?q=Noppiboon%20S.%0D%0AHochareon%20L."> Noppiboon S. Hochareon L.</a>, <a href="https://publications.waset.org/abstracts/search?q=Kitsuban%20P."> Kitsuban P.</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Third generation of vaccines is based on gene therapy where DNA is introduced into patients. The antigenic or therapeutic proteins encoded from transgenes DNA triggers an immune-response to counteract various diseases. Moreover, DNA vaccine offers the customization of its ability on protection and treatment with high stability. The production of DNA vaccines become of interest. According to USFDA guidance for industry, the recommended limits for impurities from host cell are lower than 1%, and the active conformation homogeneity supercoiled DNA, is more than 80%. Thus, the purification strategy using two-steps chromatography has been established and verified for its robustness. Herein, pVax1/lacZ, a pre-approved USFDA DNA vaccine backbone, was used and transformed into E. coli strain DH5α. Three purification process parameters including sample-loading flow rate, the salt concentration in washing and eluting buffer, were studied and the experiment was designed using response surface method with central composite face-centered (CCF) as a model. The designed range of selected parameters was 10% variation from the optimized set point as a safety factor. The purity in the percentage of supercoiled conformation obtained from each chromatography step, AIEX and HIC, were analyzed by HPLC. The response data were used to establish regression model and statistically analyzed followed by Monte Carlo simulation using SAS JMP. The results on the purity of the product obtained from AIEX and HIC are between 89.4 to 92.5% and 88.3 to 100.0%, respectively. Monte Carlo simulation showed that the pVAX1/lacZ purification process is robust with confidence intervals of 0.90 in range of 90.18-91.00% and 95.88-100.00%, for AIEX and HIC respectively. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=AIEX" title="AIEX">AIEX</a>, <a href="https://publications.waset.org/abstracts/search?q=DNA%20vaccine" title=" DNA vaccine"> DNA vaccine</a>, <a href="https://publications.waset.org/abstracts/search?q=HIC" title=" HIC"> HIC</a>, <a href="https://publications.waset.org/abstracts/search?q=puification" title=" puification"> puification</a>, <a href="https://publications.waset.org/abstracts/search?q=response%20surface%20method" title=" response surface method"> response surface method</a>, <a href="https://publications.waset.org/abstracts/search?q=robustness" title=" robustness"> robustness</a> </p> <a href="https://publications.waset.org/abstracts/95304/process-development-of-pvax1lacz-plasmid-dna-purification-using-design-of-experiment" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/95304.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">206</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">75</span> Computational Insights Into Allosteric Regulation of Lyn Protein Kinase: Structural Dynamics and Impacts of Cancer-Related Mutations</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mina%20Rabipour">Mina Rabipour</a>, <a href="https://publications.waset.org/abstracts/search?q=Elena%20Pallaske"> Elena Pallaske</a>, <a href="https://publications.waset.org/abstracts/search?q=Floyd%20Hassenr%C3%BCck"> Floyd Hassenrück</a>, <a href="https://publications.waset.org/abstracts/search?q=Rocio%20Rebollido-Rios"> Rocio Rebollido-Rios</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Protein tyrosine kinases, including Lyn kinase of the Src family kinases (SFK), regulate cell proliferation, survival, and differentiation. Lyn kinase has been implicated in various cancers, positioning it as a promising therapeutic target. However, the conserved ATP-binding pocket across SFKs makes developing selective inhibitors challenging. This study aims to address this limitation by exploring the potential for allosteric modulation of Lyn kinase, focusing on how its structural dynamics and specific oncogenic mutations impact its conformation and function. To achieve this, we combined homology modeling, molecular dynamics simulations, and data science techniques to conduct microsecond-length simulations. Our approach allowed a detailed investigation into the interplay between Lyn’s catalytic and regulatory domains, identifying key conformational states involved in allosteric regulation. Additionally, we evaluated the structural effects of Dasatinib, a competitive inhibitor, and ATP binding on Lyn active conformation. Notably, our simulations show that cancer-related mutations, specifically I364L/N and E290D/K, shift Lyn toward an inactive conformation, contrasting with the active state of the wild-type protein. This may suggest how these mutations contribute to aberrant signaling in cancer cells. We conducted a dynamical network analysis to assess residue-residue interactions and the impact of mutations on the Lyn intramolecular network. This revealed significant disruptions due to mutations, especially in regions distant from the ATP-binding site. These disruptions suggest potential allosteric sites as therapeutic targets, offering an alternative strategy for Lyn inhibition with higher specificity and fewer off-target effects compared to ATP-competitive inhibitors. Our findings provide insights into Lyn kinase regulation and highlight allosteric sites as avenues for selective drug development. Targeting these sites may modulate Lyn activity in cancer cells, reducing toxicity and improving outcomes. Furthermore, our computational strategy offers a scalable approach for analyzing other SFK members or kinases with similar properties, facilitating the discovery of selective allosteric modulators and contributing to precise cancer therapies. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=lyn%20tyrosine%20kinase" title="lyn tyrosine kinase">lyn tyrosine kinase</a>, <a href="https://publications.waset.org/abstracts/search?q=mutation%20analysis" title=" mutation analysis"> mutation analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=conformational%20changes" title=" conformational changes"> conformational changes</a>, <a href="https://publications.waset.org/abstracts/search?q=dynamic%20network%20analysis" title=" dynamic network analysis"> dynamic network analysis</a>, <a href="https://publications.waset.org/abstracts/search?q=allosteric%20modulation" title=" allosteric modulation"> allosteric modulation</a>, <a href="https://publications.waset.org/abstracts/search?q=targeted%20inhibition" title=" targeted inhibition"> targeted inhibition</a> </p> <a href="https://publications.waset.org/abstracts/193523/computational-insights-into-allosteric-regulation-of-lyn-protein-kinase-structural-dynamics-and-impacts-of-cancer-related-mutations" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/193523.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">14</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">74</span> Slaughter and Carcass Characterization, and Sensory Qualities of Native, Pure, and Upgraded Breeds of Goat Raised in the Philippines</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jonathan%20N.%20Nayga">Jonathan N. Nayga</a>, <a href="https://publications.waset.org/abstracts/search?q=Emelita%20B.%20Valdez"> Emelita B. Valdez</a>, <a href="https://publications.waset.org/abstracts/search?q=Mila%20R.%20Andres"> Mila R. Andres</a>, <a href="https://publications.waset.org/abstracts/search?q=Beulah%20B.%20Estrada"> Beulah B. Estrada</a>, <a href="https://publications.waset.org/abstracts/search?q=Emelina%20A.%20Lopez"> Emelina A. Lopez</a>, <a href="https://publications.waset.org/abstracts/search?q=Rogelio%20B.%20Tamayo"> Rogelio B. Tamayo</a>, <a href="https://publications.waset.org/abstracts/search?q=Aubrey%20Joy%20M.%20Balbin"> Aubrey Joy M. Balbin</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Goat production is one of the activities included in integrated farming in the Philippines. Goats are raised for its meat and regardless of breed the animal is slaughtered for this purpose. In order to document the carcass yield of different goats slaughtered, five (5) different breeds of goats to include Purebred Boer and Anglo-nubian, Crossbred Boer and Anglo-nubian and Philippine Native goat were used in the study. Data on slaughter parameters, carcass characteristics, and sensory evaluation were gathered and analyzed using Complete Random Design (CRD) at 5% level of significance and the results of carcass conformation were assessed descriptively. Results showed that slaughter data such as slaughter/live weight, hot and chilled carcass weights, dressing percentage and percentage drip loss were significantly different (P>0.05) among breeds. On carcass and meat characteristics, pure breed and upgraded Boer were found to be moderately muscular while Native goat was rated as thin muscular. The color of the carcass also revealed that Purebred and crossbred Boer were described dark red, while Native goat was noted to be slightly pale. On sensory evaluation, the results indicated that there was no significant difference (P>0.05) among breeds evaluated. It is therefore concluded that purebred goat has heavier carcass, while both purebred Boer and upgrade are rated slightly muscular. It is further confirms that regardless of breed, goat will have the same sensory characteristics. Thus, it is recommended to slaughter heavier goats to obtain more carcasses with better conformation and quality. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=carcass%20quality" title="carcass quality">carcass quality</a>, <a href="https://publications.waset.org/abstracts/search?q=goat" title=" goat"> goat</a>, <a href="https://publications.waset.org/abstracts/search?q=sensory%20evaluation" title=" sensory evaluation"> sensory evaluation</a>, <a href="https://publications.waset.org/abstracts/search?q=slaughter" title=" slaughter"> slaughter</a> </p> <a href="https://publications.waset.org/abstracts/41321/slaughter-and-carcass-characterization-and-sensory-qualities-of-native-pure-and-upgraded-breeds-of-goat-raised-in-the-philippines" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/41321.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">349</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">73</span> High-Pressure Polymorphism of 4,4-Bipyridine Hydrobromide </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Michalina%20Aniola">Michalina Aniola</a>, <a href="https://publications.waset.org/abstracts/search?q=Andrzej%20Katrusiak"> Andrzej Katrusiak</a> </p> <p class="card-text"><strong>Abstract:</strong></p> 4,4-Bipyridine is an important compound often used in chemical practice and more recently frequently applied for designing new metal organic framework (MoFs). Here we present a systematic high-pressure study of its hydrobromide salt. 4,4-Bipyridine hydrobromide monohydrate, 44biPyHBrH₂O, at ambient-pressure is orthorhombic, space group P212121 (phase a). Its hydrostatic compression shows that it is stable to 1.32 GPa at least. However, the recrystallization above 0.55 GPa reveals a new hidden b-phase (monoclinic, P21/c). Moreover, when the 44biPyHBrH2O is heated to high temperature the chemical reactions of this compound in methanol solution can be observed. High-pressure experiments were performed using a Merrill-Bassett diamond-anvil cell (DAC), modified by mounting the anvils directly on the steel supports, and X-ray diffraction measurements were carried out on a KUMA and Excalibur diffractometer equipped with an EOS CCD detector. At elevated pressure, the crystal of 44biPyHBrH₂O exhibits several striking and unexpected features. No signs of instability of phase a were detected to 1.32 GPa, while phase b becomes stable at above 0.55 GPa, as evidenced by its recrystallizations. Phases a and b of 44biPyHBrH2O are partly isostructural: their unit-cell dimensions and the arrangement of ions and water molecules are similar. In phase b the HOH-Br- chains double the frequency of their zigzag motifs, compared to phase a, and the 44biPyH+ cations change their conformation. Like in all monosalts of 44biPy determined so far, in phase a the pyridine rings are twisted by about 30 degrees about bond C4-C4 and in phase b they assume energy-unfavorable planar conformation. Another unusual feature of 44biPyHBrH2O is that all unit-cell parameters become longer on the transition from phase a to phase b. Thus the volume drop on the transition to high-pressure phase b totally depends on the shear strain of the lattice. Higher temperature triggers chemical reactions of 44biPyHBrH2O with methanol. When the saturated methanol solution compound precipitated at 0.1 GPa and temperature of 423 K was required to dissolve all the sample, the subsequent slow recrystallization at isochoric conditions resulted in disalt 4,4-bipyridinium dibromide. For the 44biPyHBrH2O sample sealed in the DAC at 0.35 GPa, then dissolved at isochoric conditions at 473 K and recrystallized by slow controlled cooling, a reaction of N,N-dimethylation took place. It is characteristic that in both high-pressure reactions of 44biPyHBrH₂O the unsolvated disalt products were formed and that free base 44biPy and H₂O remained in the solution. The observed reactions indicate that high pressure destabilized ambient-pressure salts and favors new products. Further studies on pressure-induced reactions are carried out in order to better understand the structural preferences induced by pressure. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=conformation" title="conformation">conformation</a>, <a href="https://publications.waset.org/abstracts/search?q=high-pressure" title=" high-pressure"> high-pressure</a>, <a href="https://publications.waset.org/abstracts/search?q=negative%20area%20compressibility" title=" negative area compressibility"> negative area compressibility</a>, <a href="https://publications.waset.org/abstracts/search?q=polymorphism" title=" polymorphism"> polymorphism</a> </p> <a href="https://publications.waset.org/abstracts/51916/high-pressure-polymorphism-of-44-bipyridine-hydrobromide" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/51916.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">246</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">72</span> A Basic Modeling Approach for the 3D Protein Structure of Insulin</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Daniel%20Zarzo%20Montes">Daniel Zarzo Montes</a>, <a href="https://publications.waset.org/abstracts/search?q=Manuel%20Zarzo%20Castell%C3%B3"> Manuel Zarzo Castelló</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Proteins play a fundamental role in biology, but their structure is complex, and it is a challenge for teachers to conceptually explain the differences between their primary, secondary, tertiary, and quaternary structures. On the other hand, there are currently many computer programs to visualize the 3D structure of proteins, but they require advanced training and knowledge. Moreover, it becomes difficult to visualize the sequence of amino acids in these models, and how the protein conformation is reached. Given this drawback, a simple and instructive procedure is proposed in order to teach the protein structure to undergraduate and graduate students. For this purpose, insulin has been chosen because it is a protein that consists of 51 amino acids, a relatively small number. The methodology has consisted of the use of plastic atom models, which are frequently used in organic chemistry and biochemistry to explain the chirality of biomolecules. For didactic purposes, when the aim is to teach the biochemical foundations of proteins, a manipulative system seems convenient, starting from the chemical structure of amino acids. It has the advantage that the bonds between amino acids can be conveniently rotated, following the pattern marked by the 3D models. First, the 51 amino acids were modeled, and then they were linked according to the sequence of this protein. Next, the three disulfide bonds that characterize the stability of insulin have been established, and then the alpha-helix structure has been formed. In order to reach the tertiary 3D conformation of this protein, different interactive models available on the Internet have been visualized. In conclusion, the proposed methodology seems very suitable for biology and biochemistry students because they can learn the fundamentals of protein modeling by means of a manipulative procedure as a basis for understanding the functionality of proteins. This methodology would be conveniently useful for a biology or biochemistry laboratory practice, either at the pre-graduate or university level. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=protein%20structure" title="protein structure">protein structure</a>, <a href="https://publications.waset.org/abstracts/search?q=3D%20model" title=" 3D model"> 3D model</a>, <a href="https://publications.waset.org/abstracts/search?q=insulin" title=" insulin"> insulin</a>, <a href="https://publications.waset.org/abstracts/search?q=biomolecule" title=" biomolecule"> biomolecule</a> </p> <a href="https://publications.waset.org/abstracts/182829/a-basic-modeling-approach-for-the-3d-protein-structure-of-insulin" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/182829.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">55</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">71</span> Modification of Escherichia coli PtolT Expression Vector via Site-Directed Mutagenesis</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yakup%20Ulusu">Yakup Ulusu</a>, <a href="https://publications.waset.org/abstracts/search?q=Numan%20Eczac%C4%B1o%C4%9Flu"> Numan Eczacıoğlu</a>, <a href="https://publications.waset.org/abstracts/search?q=%C4%B0sa%20G%C3%B6k%C3%A7e"> İsa Gökçe</a>, <a href="https://publications.waset.org/abstracts/search?q=Helen%20Waller"> Helen Waller</a>, <a href="https://publications.waset.org/abstracts/search?q=Jeremy%20H.%20Lakey"> Jeremy H. Lakey</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Besides having the appropriate amino acid sequence to perform the function of proteins, it is important to have correct conformation after this sequence to process. To consist of this conformation depends on the amino acid sequence at the primary structure, hydrophobic interaction, chaperones and enzymes in charge of folding etc. Misfolded proteins are not functional and tend to be aggregated. Cysteine originating disulfide cross-links make stable this conformation of functional proteins. When two of the cysteine amino acids come side by side, disulfide bond is established that forms a cystine bridge. Due to this feature cysteine plays an important role on the formation of three-dimensional structure of many proteins. There are two cysteine amino acids (C44, C69) in the Tol-A-III protein. Unlike protein disulfide bonds from within his own, any non-specific cystine bridge causes a change in the three dimensional structure of the protein. Proteins can be expressed in various host cells as directly or fusion (chimeric). As a result of overproduction of the recombinant proteins, aggregation of insoluble proteins in the host cell can occur by forming a crystal structure called inclusion body. In general fusion proteins are produced for provide affinity tags to make proteins more soluble and production of some toxic proteins via fusion protein expression system like pTolT. Proteins can be modified by using a site-directed mutagenesis. By this way, creation of non-specific disulfide crosslinks can be prevented at fusion protein expression system via the present cysteine replaced by another amino acid such as serine, glycine or etc. To do this, we need; a DNA molecule that contains the gene that encodes for the target protein, required primers for mutation to be designed according to site directed mutagenesis reaction. This study was aimed to be replaced cysteine encoding codon TGT with serine encoding codon AGT. For this sense and reverse primers designed (given below) and used site-directed mutagenesis reaction. Several new copy of the template plasmid DNA has been formed with above mentioned mutagenic primers via polymerase chain reaction (PCR). PCR product consists of both the master template DNA (wild type) and the new DNA sequences containing mutations. Dpn-l endonuclease restriction enzyme which is specific for methylated DNA and cuts them to the elimination of the master template DNA. E. coli cells obtained after transformation were incubated LB medium with antibiotic. After purification of plasmid DNA from E. coli, the presence of the mutation was determined by DNA sequence analysis. Developed this new plasmid is called PtolT-δ. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=site%20directed%20mutagenesis" title="site directed mutagenesis">site directed mutagenesis</a>, <a href="https://publications.waset.org/abstracts/search?q=Escherichia%20coli" title=" Escherichia coli"> Escherichia coli</a>, <a href="https://publications.waset.org/abstracts/search?q=pTolT" title=" pTolT"> pTolT</a>, <a href="https://publications.waset.org/abstracts/search?q=protein%20expression" title=" protein expression"> protein expression</a> </p> <a href="https://publications.waset.org/abstracts/49400/modification-of-escherichia-coli-ptolt-expression-vector-via-site-directed-mutagenesis" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/49400.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">374</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">70</span> Influence of Preparation, Characterisation and Application of Carbon Nano Tube</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Dhaivat%20S.%20Soni">Dhaivat S. Soni</a>, <a href="https://publications.waset.org/abstracts/search?q=Snehal%20Thakor"> Snehal Thakor</a>, <a href="https://publications.waset.org/abstracts/search?q=Afroz%20Bhatti"> Afroz Bhatti</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The prepare CNTs in bulk quantity by as easiest as possible method with highly pure and small diameter. Prepared CNTs first charactered its structural parameter for the conformation of CNTs and purity. Surface morphology of CNTs stured by using various instruments finally study application of prepared CNTs in various field. Carbon nanotubes (CNTs) were synthesized in large scale by pyrolyzing activated carbon in sealed autoclaves. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=nanostructures" title="nanostructures">nanostructures</a>, <a href="https://publications.waset.org/abstracts/search?q=nanotubes" title=" nanotubes"> nanotubes</a>, <a href="https://publications.waset.org/abstracts/search?q=carbon" title=" carbon"> carbon</a>, <a href="https://publications.waset.org/abstracts/search?q=pyrolysis" title=" pyrolysis"> pyrolysis</a> </p> <a href="https://publications.waset.org/abstracts/24167/influence-of-preparation-characterisation-and-application-of-carbon-nano-tube" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/24167.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">398</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">69</span> Electrical Investigations of Polyaniline/Graphitic Carbon Nitride Composites Using Broadband Dielectric Spectroscopy</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20A.%20Moussa">M. A. Moussa</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20H.%20Abdel%20Rehim"> M. H. Abdel Rehim</a>, <a href="https://publications.waset.org/abstracts/search?q=G.M.%20Turky"> G.M. Turky</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Polyaniline composites with carbon nitride, to overcome compatibility restriction with graphene, were prepared with the solution method. FTIR and Uv-vis spectra were used for structural conformation. While XRD and XPS confirmed the structures in addition to estimation of nitrogen atom surroundings, the pore sizes and the active surface area were determined from BET adsorption isotherm. The electrical and dielectric parameters were measured and calculated with BDS . <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=carbon%20nitride" title="carbon nitride">carbon nitride</a>, <a href="https://publications.waset.org/abstracts/search?q=dynamic%20relaxation" title=" dynamic relaxation"> dynamic relaxation</a>, <a href="https://publications.waset.org/abstracts/search?q=electrical%20conductivity" title=" electrical conductivity"> electrical conductivity</a>, <a href="https://publications.waset.org/abstracts/search?q=polyaniline" title=" polyaniline"> polyaniline</a> </p> <a href="https://publications.waset.org/abstracts/135615/electrical-investigations-of-polyanilinegraphitic-carbon-nitride-composites-using-broadband-dielectric-spectroscopy" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/135615.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">142</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">68</span> Genetic Variation of Lactoferrin Gene and Its Association with Productive Traits in Egyptian Goats</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Othman%20E.%20Othman">Othman E. Othman</a>, <a href="https://publications.waset.org/abstracts/search?q=Hassan%20R.%20Darwish"> Hassan R. Darwish</a>, <a href="https://publications.waset.org/abstracts/search?q=Amira%20M.%20Nowier"> Amira M. Nowier</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Lactoferrin (LF) is a multifunctional protein involved in economically production traits like milk protein composition and skeletal structure in small ruminants including sheep and goat. So, LF gene - with its genetic polymorphisms associated with production traits - is considered a candidate genetic marker used in marker-assisted selection in goats. This study aimed to identify the different alleles and genotypes of this gene in three Egyptian goat breeds using PCR-SSCP (polymerase chain reaction-single-strand conformation polymorphism) and DNA sequencing. Genomic DNA was extracted from 120 animals belonging to Barki, Zaraibi, and Damascus goat breeds. Using specific primers, PCR amplified 247-bp fragments from exon 2 of LF goat gene. The PCR products were subjected to Single-Strand Conformation Polymorphism (SSCP) technique. The results showed the presence of two genotypes GG and AG in the tested animals. The frequencies of both genotypes varied among the three tested breeds with the highest frequencies of GG genotype in all tested goat breeds. The sequence analysis of PCR products representing these two detected genotypes declared the presence of an SNP (single nucleotide polymorphisms) substitution (G/A) among G and A alleles of this gene. The association between different LF genotypes and milk composition as well as body measurement was estimated. The comparison showed that the animals possess AG genotypes are superior over those with GG genotypes for different parameters of milk protein compositions and skeletal structures. This finding declared that allele A of LF gene is considered the promising marker for the productive traits in goat. In conclusion, the Egyptian goat breeds will be needed to enhance their milk protein composition and growth trait parameters through the increasing of allele A frequency in their herds depending on the superior production traits of this allele in goats. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=lLactoferrin%20gene" title="lLactoferrin gene">lLactoferrin gene</a>, <a href="https://publications.waset.org/abstracts/search?q=PCR-SSCP" title=" PCR-SSCP"> PCR-SSCP</a>, <a href="https://publications.waset.org/abstracts/search?q=SNPs" title=" SNPs"> SNPs</a>, <a href="https://publications.waset.org/abstracts/search?q=Egyptian%20goat" title=" Egyptian goat"> Egyptian goat</a> </p> <a href="https://publications.waset.org/abstracts/94736/genetic-variation-of-lactoferrin-gene-and-its-association-with-productive-traits-in-egyptian-goats" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/94736.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">155</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">67</span> Structure and Mechanics Patterns in the Assembly of Type V Intermediate-Filament Protein-Based Fibers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Mark%20Bezner">Mark Bezner</a>, <a href="https://publications.waset.org/abstracts/search?q=Shani%20Deri"> Shani Deri</a>, <a href="https://publications.waset.org/abstracts/search?q=Tom%20Trigano"> Tom Trigano</a>, <a href="https://publications.waset.org/abstracts/search?q=Kfir%20Ben-Harush"> Kfir Ben-Harush</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Intermediate filament (IF) proteins-based fibers are among the toughest fibers in nature, as was shown by native hagfish slime threads and by synthetic fibers that are based on type V IF-proteins, the nuclear lamins. It is assumed that their mechanical performance stems from two major factors: (1) the transition from elastic -helices to stiff-sheets during tensile load; and (2) the specific organization of the coiled-coil proteins into a hierarchical network of nano-filaments. Here, we investigated the interrelationship between these two factors by using wet-spun fibers based on C. elegans (Ce) lamin. We found that Ce-lamin fibers, whether assembled in aqueous or alcoholic solutions, had the same nonlinear mechanical behavior, with the elastic region ending at ~5%. The pattern of the transition was, however, different: the ratio between -helices and -sheets/random coils was relatively constant until a 20% strain for fibers assembled in an aqueous solution, whereas for fibers assembled in 70% ethanol, the transition ended at a 6% strain. This structural phenomenon in alcoholic solution probably occurred through the transition between compacted and extended conformation of the random coil, and not between -helix and -sheets, as cycle analyses had suggested. The different transition pattern can also be explained by the different higher order organization of Ce-lamins in aqueous or alcoholic solutions, as demonstrated by introducing a point mutation in conserved residue in Ce-lamin gene that alter the structure of the Ce-lamins’ nano-fibrils. In addition, biomimicking the layered structure of silk and hair fibers by coating the Ce-lamin fiber with a hydrophobic layer enhanced fiber toughness and lead to a reversible transition between -helix and the extended conformation. This work suggests that different hierarchical structures, which are formed by specific assembly conditions, lead to diverse secondary structure transitions patterns, which in turn affect the fibers’ mechanical properties. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=protein-based%20fibers" title="protein-based fibers">protein-based fibers</a>, <a href="https://publications.waset.org/abstracts/search?q=intermediate%20filaments%20%28IF%29%20assembly" title=" intermediate filaments (IF) assembly"> intermediate filaments (IF) assembly</a>, <a href="https://publications.waset.org/abstracts/search?q=toughness" title=" toughness"> toughness</a>, <a href="https://publications.waset.org/abstracts/search?q=structure-property%20relationships" title=" structure-property relationships"> structure-property relationships</a> </p> <a href="https://publications.waset.org/abstracts/155383/structure-and-mechanics-patterns-in-the-assembly-of-type-v-intermediate-filament-protein-based-fibers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/155383.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">110</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">66</span> Analytical Modeling of Globular Protein-Ferritin in α-Helical Conformation: A White Noise Functional Approach</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Vernie%20C.%20Convicto">Vernie C. Convicto</a>, <a href="https://publications.waset.org/abstracts/search?q=Henry%20P.%20Aringa"> Henry P. Aringa</a>, <a href="https://publications.waset.org/abstracts/search?q=Wilson%20I.%20Barredo"> Wilson I. Barredo</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study presents a conformational model of the helical structures of globular protein particularly ferritin in the framework of white noise path integral formulation by using Associated Legendre functions, Bessel and convolution of Bessel and trigonometric functions as modulating functions. The model incorporates chirality features of proteins and their helix-turn-helix sequence structural motif. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=globular%20protein" title="globular protein">globular protein</a>, <a href="https://publications.waset.org/abstracts/search?q=modulating%20function" title=" modulating function"> modulating function</a>, <a href="https://publications.waset.org/abstracts/search?q=white%20noise" title=" white noise"> white noise</a>, <a href="https://publications.waset.org/abstracts/search?q=winding%20probability" title=" winding probability"> winding probability</a> </p> <a href="https://publications.waset.org/abstracts/29779/analytical-modeling-of-globular-protein-ferritin-in-a-helical-conformation-a-white-noise-functional-approach" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/29779.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">476</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">65</span> Marine Propeller Cavitation Analysis Using BEM</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ehsan%20Yari">Ehsan Yari</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, a numerical study of sheet cavitation has been performed on DTMB4119 and E779A marine propellers with the boundary element method. In propeller design, various parameters of geometry and fluid are incorporated. So a program is needed to solve the flow taking the whole parameters changing into account. The capability of analyzing the wetted and cavitation flow around propellers in steady, unsteady, uniform, and non-uniform conditions while decreasing computational time compared to numerical finite volume methods with acceptable precision are the characteristic features of the present method. Moreover, modifying the position of the detachment point and its corresponding potential value has been considered. Numerical results have been validated with experimental data, showing a good conformation. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cavitation" title="cavitation">cavitation</a>, <a href="https://publications.waset.org/abstracts/search?q=BEM" title=" BEM"> BEM</a>, <a href="https://publications.waset.org/abstracts/search?q=DTMB4119" title=" DTMB4119"> DTMB4119</a>, <a href="https://publications.waset.org/abstracts/search?q=E779A" title=" E779A"> E779A</a> </p> <a href="https://publications.waset.org/abstracts/182003/marine-propeller-cavitation-analysis-using-bem" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/182003.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">69</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">64</span> Finite Element Molecular Modeling: A Structural Method for Large Deformations</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=A.%20Rezaei">A. Rezaei</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Huisman"> M. Huisman</a>, <a href="https://publications.waset.org/abstracts/search?q=W.%20Van%20Paepegem"> W. Van Paepegem</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Atomic interactions in molecular systems are mainly studied by particle mechanics. Nevertheless, researches have also put on considerable effort to simulate them using continuum methods. In early 2000, simple equivalent finite element models have been developed to study the mechanical properties of carbon nanotubes and graphene in composite materials. Afterward, many researchers have employed similar structural simulation approaches to obtain mechanical properties of nanostructured materials, to simplify interface behavior of fiber-reinforced composites, and to simulate defects in carbon nanotubes or graphene sheets, etc. These structural approaches, however, are limited to small deformations due to complicated local rotational coordinates. This article proposes a method for the finite element simulation of molecular mechanics. For ease in addressing the approach, here it is called Structural Finite Element Molecular Modeling (SFEMM). SFEMM method improves the available structural approaches for large deformations, without using any rotational degrees of freedom. Moreover, the method simulates molecular conformation, which is a big advantage over the previous approaches. Technically, this method uses nonlinear multipoint constraints to simulate kinematics of the atomic multibody interactions. Only truss elements are employed, and the bond potentials are implemented through constitutive material models. Because the equilibrium bond- length, bond angles, and bond-torsion potential energies are intrinsic material parameters, the model is independent of initial strains or stresses. In this paper, the SFEMM method has been implemented in ABAQUS finite element software. The constraints and material behaviors are modeled through two Fortran subroutines. The method is verified for the bond-stretch, bond-angle and bond-torsion of carbon atoms. Furthermore, the capability of the method in the conformation simulation of molecular structures is demonstrated via a case study of a graphene sheet. Briefly, SFEMM builds up a framework that offers more flexible features over the conventional molecular finite element models, serving the structural relaxation modeling and large deformations without incorporating local rotational degrees of freedom. Potentially, the method is a big step towards comprehensive molecular modeling with finite element technique, and thereby concurrently coupling an atomistic domain to a solid continuum domain within a single finite element platform. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=finite%20element" title="finite element">finite element</a>, <a href="https://publications.waset.org/abstracts/search?q=large%20deformation" title=" large deformation"> large deformation</a>, <a href="https://publications.waset.org/abstracts/search?q=molecular%20mechanics" title=" molecular mechanics"> molecular mechanics</a>, <a href="https://publications.waset.org/abstracts/search?q=structural%20method" title=" structural method"> structural method</a> </p> <a href="https://publications.waset.org/abstracts/116070/finite-element-molecular-modeling-a-structural-method-for-large-deformations" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/116070.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">152</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">63</span> Protein Tertiary Structure Prediction by a Multiobjective Optimization and Neural Network Approach</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Alexandre%20Barbosa%20de%20Almeida">Alexandre Barbosa de Almeida</a>, <a href="https://publications.waset.org/abstracts/search?q=Telma%20Woerle%20de%20Lima%20Soares"> Telma Woerle de Lima Soares</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Protein structure prediction is a challenging task in the bioinformatics field. The biological function of all proteins majorly relies on the shape of their three-dimensional conformational structure, but less than 1% of all known proteins in the world have their structure solved. This work proposes a deep learning model to address this problem, attempting to predict some aspects of the protein conformations. Throughout a process of multiobjective dominance, a recurrent neural network was trained to abstract the particular bias of each individual multiobjective algorithm, generating a heuristic that could be useful to predict some of the relevant aspects of the three-dimensional conformation process formation, known as protein folding. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ab%20initio%20heuristic%20modeling" title="Ab initio heuristic modeling">Ab initio heuristic modeling</a>, <a href="https://publications.waset.org/abstracts/search?q=multiobjective%20optimization" title=" multiobjective optimization"> multiobjective optimization</a>, <a href="https://publications.waset.org/abstracts/search?q=protein%20structure%20prediction" title=" protein structure prediction"> protein structure prediction</a>, <a href="https://publications.waset.org/abstracts/search?q=recurrent%20neural%20network" title=" recurrent neural network"> recurrent neural network</a> </p> <a href="https://publications.waset.org/abstracts/141565/protein-tertiary-structure-prediction-by-a-multiobjective-optimization-and-neural-network-approach" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/141565.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">205</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">62</span> SEC-MALLS Study of Hyaluronic Acid and BSA Thermal Degradation in Powder and in Solution</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Vasile%20Simulescu">Vasile Simulescu</a>, <a href="https://publications.waset.org/abstracts/search?q=Jakub%20Mondek"> Jakub Mondek</a>, <a href="https://publications.waset.org/abstracts/search?q=Miloslav%20Peka%C5%99"> Miloslav Pekař</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Hyaluronic acid (HA) is an anionic glycosaminoglycan distributed throughout connective, epithelial and neural tissues. The importance of hyaluronic acid increased in the last decades. It has many applications in medicine and cosmetics. Hyaluronic acid has been used in attempts to treat osteoarthritis of the knee via injecting it into the joint. Bovine serum albumin (also known as BSA) is a protein derived from cows, which has many biochemical applications. The aim of our research work was to compare the thermal degradation of hyaluronic acid and BSA in powder and in solution, by determining changes in molar mass and conformation, by using SEC-MALLS (size exclusion chromatography -multi angle laser light scattering). The aim of our research work was to observe the degradation in powder and in solution of different molar mass hyaluronic acid samples, at different temperatures for certain periods. The degradation of the analyzed samples was mainly observed by modifications in molar mass. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=thermal%20degradation" title="thermal degradation">thermal degradation</a>, <a href="https://publications.waset.org/abstracts/search?q=hyaluronic%20acid" title=" hyaluronic acid"> hyaluronic acid</a>, <a href="https://publications.waset.org/abstracts/search?q=BSA" title=" BSA"> BSA</a>, <a href="https://publications.waset.org/abstracts/search?q=SEC-MALLS" title=" SEC-MALLS"> SEC-MALLS</a> </p> <a href="https://publications.waset.org/abstracts/20733/sec-malls-study-of-hyaluronic-acid-and-bsa-thermal-degradation-in-powder-and-in-solution" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/20733.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">505</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">61</span> Switchable Lipids: From a Molecular Switch to a pH-Sensitive System for the Drug and Gene Delivery</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jeanne%20Leblond">Jeanne Leblond</a>, <a href="https://publications.waset.org/abstracts/search?q=Warren%20Viricel"> Warren Viricel</a>, <a href="https://publications.waset.org/abstracts/search?q=Amira%20Mbarek"> Amira Mbarek</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Although several products have reached the market, gene therapeutics are still in their first stages and require optimization. It is possible to improve their lacking efficiency by the use of carefully engineered vectors, able to carry the genetic material through each of the biological barriers they need to cross. In particular, getting inside the cell is a major challenge, because these hydrophilic nucleic acids have to cross the lipid-rich plasmatic and/or endosomal membrane, before being degraded into lysosomes. It takes less than one hour for newly endocytosed liposomes to reach highly acidic lysosomes, meaning that the degradation of the carried gene occurs rapidly, thus limiting the transfection efficiency. We propose to use a new pH-sensitive lipid able to change its conformation upon protonation at endosomal pH values, leading to the disruption of the lipidic bilayer and thus to the fast release of the nucleic acids into the cytosol. It is expected that this new pH-sensitive mechanism promote endosomal escape of the gene, thereby its transfection efficiency. The main challenge of this work was to design a preparation presenting fast-responding lipidic bilayer destabilization properties at endosomal pH 5 while remaining stable at blood pH value and during storage. A series of pH-sensitive lipids able to perform a conformational switch upon acidification were designed and synthesized. Liposomes containing these switchable lipids, as well as co-lipids were prepared and characterized. The liposomes were stable at 4°C and pH 7.4 for several months. Incubation with siRNA led to the full entrapment of nucleic acids as soon as the positive/negative charge ratio was superior to 2. The best liposomal formulation demonstrated a silencing efficiency up to 10% on HeLa cells, very similar to a commercial agent, with a lowest toxicity than the commercial agent. Using flow cytometry and microscopy assays, we demonstrated that drop of pH was required for the transfection efficiency, since bafilomycin blocked the transfection efficiency. Additional evidence was brought by the synthesis of a negative control lipid, which was unable to switch its conformation, and consequently exhibited no transfection ability. Mechanistic studies revealed that the uptake was mediated through endocytosis, by clathrin and caveolae pathways, as reported for previous lipid nanoparticle systems. This potent system was used for the treatment of hypercholesterolemia. The switchable lipids were able to knockdown PCSK9 expression on human hepatocytes (Huh-7). Its efficiency is currently evaluated on in vivo mice model of PCSK9 KO mice. In summary, we designed and optimized a new cationic pH-sensitive lipid for gene delivery. Its transfection efficiency is similar to the best available commercial agent, without the usually associated toxicity. The promising results lead to its use for the treatment of hypercholesterolemia on a mice model. Anticancer applications and pulmonary chronic disease are also currently investigated. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=liposomes" title="liposomes">liposomes</a>, <a href="https://publications.waset.org/abstracts/search?q=siRNA" title=" siRNA"> siRNA</a>, <a href="https://publications.waset.org/abstracts/search?q=pH-sensitive" title=" pH-sensitive"> pH-sensitive</a>, <a href="https://publications.waset.org/abstracts/search?q=molecular%20switch" title=" molecular switch"> molecular switch</a> </p> <a href="https://publications.waset.org/abstracts/46460/switchable-lipids-from-a-molecular-switch-to-a-ph-sensitive-system-for-the-drug-and-gene-delivery" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/46460.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">204</span> </span> </div> </div> <ul class="pagination"> <li class="page-item disabled"><span class="page-link">&lsaquo;</span></li> <li class="page-item active"><span class="page-link">1</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=conformation&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=conformation&page=3">3</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=conformation&page=2" rel="next">&rsaquo;</a></li> </ul> </div> </main> <footer> <div id="infolinks" class="pt-3 pb-2"> <div class="container"> <div style="background-color:#f5f5f5;" class="p-3"> <div class="row"> <div class="col-md-2"> <ul class="list-unstyled"> About <li><a href="https://waset.org/page/support">About Us</a></li> <li><a href="https://waset.org/page/support#legal-information">Legal</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/WASET-16th-foundational-anniversary.pdf">WASET celebrates its 16th foundational anniversary</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Account <li><a href="https://waset.org/profile">My Account</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Explore <li><a href="https://waset.org/disciplines">Disciplines</a></li> <li><a href="https://waset.org/conferences">Conferences</a></li> <li><a href="https://waset.org/conference-programs">Conference Program</a></li> <li><a href="https://waset.org/committees">Committees</a></li> <li><a href="https://publications.waset.org">Publications</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Research <li><a href="https://publications.waset.org/abstracts">Abstracts</a></li> <li><a href="https://publications.waset.org">Periodicals</a></li> <li><a href="https://publications.waset.org/archive">Archive</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Open Science <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Philosophy.pdf">Open Science Philosophy</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Science-Award.pdf">Open Science Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Open-Society-Open-Science-and-Open-Innovation.pdf">Open Innovation</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Postdoctoral-Fellowship-Award.pdf">Postdoctoral Fellowship Award</a></li> <li><a target="_blank" rel="nofollow" href="https://publications.waset.org/static/files/Scholarly-Research-Review.pdf">Scholarly Research Review</a></li> </ul> </div> <div class="col-md-2"> <ul class="list-unstyled"> Support <li><a href="https://waset.org/page/support">Support</a></li> <li><a href="https://waset.org/profile/messages/create">Contact Us</a></li> <li><a href="https://waset.org/profile/messages/create">Report Abuse</a></li> </ul> </div> </div> </div> </div> </div> <div class="container text-center"> <hr style="margin-top:0;margin-bottom:.3rem;"> <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" class="text-muted small">Creative Commons Attribution 4.0 International License</a> <div id="copy" class="mt-2">© 2024 World Academy of Science, Engineering and Technology</div> </div> </footer> <a href="javascript:" id="return-to-top"><i class="fas fa-arrow-up"></i></a> <div class="modal" id="modal-template"> <div class="modal-dialog"> <div class="modal-content"> <div class="row m-0 mt-1"> <div class="col-md-12"> <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button> </div> </div> <div class="modal-body"></div> </div> </div> </div> <script src="https://cdn.waset.org/static/plugins/jquery-3.3.1.min.js"></script> <script src="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/js/bootstrap.bundle.min.js"></script> <script src="https://cdn.waset.org/static/js/site.js?v=150220211556"></script> <script> jQuery(document).ready(function() { /*jQuery.get("https://publications.waset.org/xhr/user-menu", function (response) { jQuery('#mainNavMenu').append(response); });*/ jQuery.get({ url: "https://publications.waset.org/xhr/user-menu", cache: false }).then(function(response){ jQuery('#mainNavMenu').append(response); }); }); </script> </body> </html>