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Design and setting: All Orthodontic photographs are taken in the Medical Photography Department at Queen’s Hospital. Retrospective audit with data collected between January - March 2023. Gold standard: Institute of Medical Illustrators (IMI) standard 12 photographs: 6 extraoral and 6 intraoral. 100% of patients to have the standard 12 photographs meeting a satisfactory diagnostic quality. Materials and methods: 30 patients randomly selected. All photographs analysed against the IMI gold standard. Results: A total of 360 photographs were analysed. 100% of the photographs had the 12 photographic views. Of which, 93.1% met the gold standard. Of the extraoral photos: 99.4% met the gold standard, 0.6% had incorrect head positioning. Of the intraoral photographs: 87.2% met the gold standard. The most common intraoral errors were: the presence of saliva pooling (7.2%), insufficient soft tissue retraction (3.3%), incomplete occlusal surface visibility (2.2%) and mirror fogging (1.1%). Conclusion: The gold standard was not met, however the overall standard of Orthodontic photographs is high. Further training of the Medical Photography team is needed to improve the quality of photographs. Following the training, the audit will be repeated. High-quality clinical photographs are an important part of clinical record keeping. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=orthodontics" title="orthodontics">orthodontics</a>, <a href="https://publications.waset.org/abstracts/search?q=paediatric" title=" paediatric"> paediatric</a>, <a href="https://publications.waset.org/abstracts/search?q=photography" title=" photography"> photography</a>, <a href="https://publications.waset.org/abstracts/search?q=audit" title=" audit"> audit</a> </p> <a href="https://publications.waset.org/abstracts/167678/assessing-the-quality-of-clinical-photographs-taken-for-orthodontic-patients-at-queens-hospital-romford" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/167678.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">118</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">5446</span> A Review on Bone Grafting, Artificial Bone Substitutes and Bone Tissue Engineering</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kasun%20Gayashan%20Samarawickrama">Kasun Gayashan Samarawickrama</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Bone diseases, defects, and fractions are commonly seen in modern life. Since bone is regenerating dynamic living tissue, it will undergo healing process naturally, it cannot recover from major bone injuries, diseases and defects. In order to overcome them, bone grafting technique was introduced. Gold standard was the best method for bone grafting for the past decades. Due to limitations of gold standard, alternative methods have been implemented. Apart from them artificial bone substitutes and bone tissue engineering have become the emerging methods with technology for bone grafting. Many bone diseases and defects will be healed permanently with these promising techniques in future. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=bone%20grafting" title="bone grafting">bone grafting</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20standard" title=" gold standard"> gold standard</a>, <a href="https://publications.waset.org/abstracts/search?q=bone%20substitutes" title=" bone substitutes"> bone substitutes</a>, <a href="https://publications.waset.org/abstracts/search?q=bone%20tissue%20engineering" title=" bone tissue engineering"> bone tissue engineering</a> </p> <a href="https://publications.waset.org/abstracts/79771/a-review-on-bone-grafting-artificial-bone-substitutes-and-bone-tissue-engineering" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/79771.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">306</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">5445</span> Characterization of Graphene Oxide Coated Gold Electrodes for Bioimpedance Measurements</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Fatma%20G%C3%BClden%20%C5%9Ei%CC%87m%C5%9Fek">Fatma Gülden Şi̇mşek</a>, <a href="https://publications.waset.org/abstracts/search?q=Osman%20Meli%CC%87h%20Can"> Osman Meli̇h Can</a>, <a href="https://publications.waset.org/abstracts/search?q=Mehmet%20Yumak"> Mehmet Yumak</a>, <a href="https://publications.waset.org/abstracts/search?q=Bora%20Gari%CC%87pcan"> Bora Gari̇pcan</a>, <a href="https://publications.waset.org/abstracts/search?q=Yekta%20%C3%9Clgen"> Yekta Ülgen</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this study, the impedance spectroscopy is used as a detection tool in order to characterize surface coating with graphene oxide. Gold electrodes are produced by standard lithography procedures and then coated with graphene oxide using self-assembly method. The impedance of redox solution through bare gold electrodes and graphene oxide coated gold electrodes is measured in the low and high frequency range. The graphene oxide coating reduces the impedance value of the gold electrode and this reduction is distinguishable in the low-frequency range. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=bioimpedance" title="bioimpedance">bioimpedance</a>, <a href="https://publications.waset.org/abstracts/search?q=electrode%20characterization" title=" electrode characterization"> electrode characterization</a>, <a href="https://publications.waset.org/abstracts/search?q=graphene%20oxide" title=" graphene oxide"> graphene oxide</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20electrodes" title=" gold electrodes"> gold electrodes</a>, <a href="https://publications.waset.org/abstracts/search?q=impedance%20spectroscopy" title=" impedance spectroscopy"> impedance spectroscopy</a> </p> <a href="https://publications.waset.org/abstracts/47355/characterization-of-graphene-oxide-coated-gold-electrodes-for-bioimpedance-measurements" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/47355.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">546</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">5444</span> The Tracking and Hedging Performances of Gold ETF Relative to Some Other Instruments in the UK</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Abimbola%20Adedeji">Abimbola Adedeji</a>, <a href="https://publications.waset.org/abstracts/search?q=Ahmad%20Shauqi%20Zubir"> Ahmad Shauqi Zubir</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper examines the profitability and risk between investing in gold exchange traded funds (ETFs) and gold mutual funds compares to gold prices. The main focus in determining whether there are similarities or differences between those financial products is the tracking error. The importance of understanding the similarities or differences between the gold ETFs, gold mutual funds and gold prices is derived from the fact that gold ETFs and gold mutual funds are used as substitutions for investors who are looking to profit from gold prices although they are short in capital. 10 hypotheses were tested. There are 3 types of tracking error used. Tracking error 1 and 3 gives results that differentiate between types of ETFs and mutual funds, hence yielding the answers in answering the hypotheses that were developed. However, tracking error 2 failed to give the answer that could shed light on the questions raised in this study. All of the results in tracking error 2 technique only telling us that the difference between the ups and downs of the financial instruments are similar, statistically to the physical gold prices movement. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold%20etf" title="gold etf">gold etf</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20mutual%20funds" title=" gold mutual funds"> gold mutual funds</a>, <a href="https://publications.waset.org/abstracts/search?q=tracking%20error" title=" tracking error"> tracking error</a> </p> <a href="https://publications.waset.org/abstracts/27595/the-tracking-and-hedging-performances-of-gold-etf-relative-to-some-other-instruments-in-the-uk" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/27595.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">429</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">5443</span> Determination of Mercury in Gold Ores by CVAAS Method</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ratna%20Siti%20Khodijah">Ratna Siti Khodijah</a>, <a href="https://publications.waset.org/abstracts/search?q=Mirzam%20Abdurrachman"> Mirzam Abdurrachman</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Gold is recovered from gold ores. Within the ores, there are not only gold but also several types of precious metals. Copper, silver, and platinum group elements (ruthenium, rhodium, palladium, rhenium, osmium, and iridium) are metals commonly found in the ores. These metals combine to form an ore because they have the same properties. It is due to their position in periodic-system-of-elements are near to gold. However, the presence of mercury in every gold ore has not been mentioned, even though it is located right next to gold in the periodic-system-of-elements and they are located in the same block, d-block. Thus, it is possible that mercury is contained in the ores. Moreover, the elements of the same group with mercury—zinc and cadmium—sometimes can be found in the ores. It is suspected that mercury can not be detected because the processing of gold ores usually using fire assay method. Before the ores melting, mercury would evaporate because it has the lowest boiling point of all precious metal in the ores. Therefore, it suggested doing research on the presence of mercury in gold ores by CVAAS method. The results of this study would obtain the amount of mercury in gold ores that should be purified. So it can be produced economically if possible. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=boiling%20point" title="boiling point">boiling point</a>, <a href="https://publications.waset.org/abstracts/search?q=d-block" title=" d-block"> d-block</a>, <a href="https://publications.waset.org/abstracts/search?q=fire%20assay" title=" fire assay"> fire assay</a>, <a href="https://publications.waset.org/abstracts/search?q=precious%20metal" title=" precious metal"> precious metal</a> </p> <a href="https://publications.waset.org/abstracts/72809/determination-of-mercury-in-gold-ores-by-cvaas-method" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/72809.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">347</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">5442</span> Trace Element Compositions of Placer Gold Samples: Implication for Gold Exploration in Northern Cameroon</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yanick%20Blaise%20Ketchaya">Yanick Blaise Ketchaya</a>, <a href="https://publications.waset.org/abstracts/search?q=Taofa%20Zhou"> Taofa Zhou</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The type of primary source of gold deposit can be explored by using the study of trace element analysis of placer gold which is a valuable exploration tool. Au-bearing deposits are investigated through the placer gold, which is an important indicator mineral. The hydrothermal fluid interacting with diverse geological settings exerts an important function on the chemical composition of gold. Consequently, alluvial gold particles from the placer deposits within the Gamba district in northern Cameroon were examined by an electron probe microanalyzer (EPMA) to show discriminant chemical signatures. The gold grains from a different locality show the same trace element composition, which appears to be in a solid solution in Au. These trace element compositions, contained in gold grains, indicate a homogeneous source. The placer gold particles have significant chemical characteristics (low Ag content), consistent with a mesothermal source. The gold particle signatures in the Gamba district, with high Te and Bi contents, reflect the chemical characteristics of the felsic host rock superimposed on the chemical signature of the hydrothermal fluid. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=hypogene%20source" title="hypogene source">hypogene source</a>, <a href="https://publications.waset.org/abstracts/search?q=Northern%20Cameroon" title=" Northern Cameroon"> Northern Cameroon</a>, <a href="https://publications.waset.org/abstracts/search?q=placer%20gold" title=" placer gold"> placer gold</a>, <a href="https://publications.waset.org/abstracts/search?q=trace%20element" title=" trace element"> trace element</a> </p> <a href="https://publications.waset.org/abstracts/157313/trace-element-compositions-of-placer-gold-samples-implication-for-gold-exploration-in-northern-cameroon" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/157313.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">118</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">5441</span> Characteristics and Key Exploration Directions of Gold Deposits in China</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Bin%20Wang">Bin Wang</a>, <a href="https://publications.waset.org/abstracts/search?q=Yong%20Xu"> Yong Xu</a>, <a href="https://publications.waset.org/abstracts/search?q=Honggang%20Qu"> Honggang Qu</a>, <a href="https://publications.waset.org/abstracts/search?q=Rongmei%20Liu"> Rongmei Liu</a>, <a href="https://publications.waset.org/abstracts/search?q=Zhenji%20Gao"> Zhenji Gao</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Based on the geodynamic environment, basic geological characteristics of minerals and so on, gold deposits in China are divided into 11 categories, of which tectonic fracture altered rock, mid-intrudes and contact zone, micro-fine disseminated and continental volcanic types are the main prospecting kinds. The metallogenic age of gold deposits in China is dominated by the Mesozoic and Cenozoic. According to the geotectonic units, geological evolution, geological conditions, spatial distribution, gold deposits types, metallogenic factors etc., 42 gold concentration areas are initially determined and have a concentrated distribution feature. On the basis of the gold exploration density, gold concentration areas are divided into high, medium and low level areas. High ones are mainly distributed in the central and eastern regions. 93.04% of the gold exploration drillings are within 500 meters, but there are some problems, such as less and shallower of drilling verification etc.. The paper discusses the resource potentials of gold deposits and proposes the future prospecting directions and suggestions. The deep and periphery of old mines in the central and eastern regions and western area, especially in Xinjiang and Qinghai, will be the future key prospecting one and have huge potential gold reserves. If the exploration depth is extended to 2,000 meters shallow, the gold resources will double. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold%20deposits" title="gold deposits">gold deposits</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20deposits%20types" title=" gold deposits types"> gold deposits types</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20concentration%20areas" title=" gold concentration areas"> gold concentration areas</a>, <a href="https://publications.waset.org/abstracts/search?q=prospecting" title=" prospecting"> prospecting</a>, <a href="https://publications.waset.org/abstracts/search?q=resource%20potentiality" title=" resource potentiality"> resource potentiality</a> </p> <a href="https://publications.waset.org/abstracts/167347/characteristics-and-key-exploration-directions-of-gold-deposits-in-china" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/167347.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">83</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">5440</span> Synthesis of Gold Nanoparticles Stabilized in Na-Montmorillonite for Nitrophenol Reduction</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Fatima%20Ammari">Fatima Ammari</a>, <a href="https://publications.waset.org/abstracts/search?q=Meriem%20Chenouf"> Meriem Chenouf</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Synthesis of gold nano particles has attracted much attention since the pioneering discovery of the high catalytic activity of supported gold nano particles in the reaction of CO oxidation at low temperature. In this research field, we used Na-montmorillonite for gold nanoparticles stabilization; different loading percentage 1, 2 and 5%. The gold nano particles were obtained using chemical reduction method using NaBH4 as reductant agent. The obtained gold nano particles Au-mont stabilized in Na-montmorillonite were used as catalysts for reduction of 4-nitrophenol to aminophenol with sodium borohydride at room temperature. The UV-Vis results confirm directly the gold nano particles formation. The XRD and N2 adsorption results showed the formation of gold nano particles in the pores of montmorillonite with an average size of 5 nm obtained on samples with 2%Au-mont. The gold particles size increased with the increase of gold loading percentage. The reduction reaction of 4-nitrophenol into 4-aminophenol with NaBH4 catalyzed by Au-Na-montmorillonite catalyst exhibits remarkably a high activity; the reaction was completed within 9 min for 1Au-mont and within 3 min for 2Au-mont. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=chemical%20reduction" title="chemical reduction">chemical reduction</a>, <a href="https://publications.waset.org/abstracts/search?q=gold" title=" gold"> gold</a>, <a href="https://publications.waset.org/abstracts/search?q=montmorillonite" title=" montmorillonite"> montmorillonite</a>, <a href="https://publications.waset.org/abstracts/search?q=nano%20particles" title=" nano particles"> nano particles</a>, <a href="https://publications.waset.org/abstracts/search?q=4-nitrophenol" title=" 4-nitrophenol"> 4-nitrophenol</a> </p> <a href="https://publications.waset.org/abstracts/34827/synthesis-of-gold-nanoparticles-stabilized-in-na-montmorillonite-for-nitrophenol-reduction" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/34827.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">336</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">5439</span> Seeking Safe Haven: An Analysis of Gold Performance during Periods of High Volatility</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Gerald%20Abdesaken">Gerald Abdesaken</a>, <a href="https://publications.waset.org/abstracts/search?q=Thomas%20O.%20Miller"> Thomas O. Miller</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper analyzes the performance of gold as a safe-haven investment. Assuming high market volatility as an impetus to seek a safe haven in gold, the return of gold relative to the stock market, as measured by the S&P 500, is tracked. Using the Chicago Board Options Exchange (CBOE) volatility index (VIX) as a measure of stock market volatility, various criteria are established for when an investor would seek a safe haven to avoid high levels of risk. The results show that in a vast majority of cases, the S&P 500 outperforms gold during these periods of high volatility and suggests investors who seek safe haven are underperforming the market. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold" title="gold">gold</a>, <a href="https://publications.waset.org/abstracts/search?q=portfolio%20management" title=" portfolio management"> portfolio management</a>, <a href="https://publications.waset.org/abstracts/search?q=safe%20haven" title=" safe haven"> safe haven</a>, <a href="https://publications.waset.org/abstracts/search?q=VIX" title=" VIX"> VIX</a> </p> <a href="https://publications.waset.org/abstracts/137176/seeking-safe-haven-an-analysis-of-gold-performance-during-periods-of-high-volatility" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/137176.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">170</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">5438</span> Volatility Spillover and Hedging Effectiveness between Gold and Stock Markets: Evidence for BRICS Countries</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Walid%20Chkili">Walid Chkili</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper investigates the dynamic relationship between gold and stock markets using data for BRICS counties. For this purpose, we estimate three multivariate GARCH models (namely CCC, DCC and BEKK) for weekly stock and gold data. Our main objective is to examine time variations in conditional correlations between the two assets and to check the effectiveness use of gold as a hedge for equity markets. Empirical results reveal that dynamic conditional correlations switch between positive and negative values over the period under study. This correlation is negative during the major financial crises suggesting that gold can act as a safe haven during the major stress period of stock markets. We also evaluate the implications for portfolio diversification and hedging effectiveness for the pair gold/stock. Our findings suggest that adding gold in the stock portfolio enhance its risk-adjusted return. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold" title="gold">gold</a>, <a href="https://publications.waset.org/abstracts/search?q=financial%20markets" title=" financial markets"> financial markets</a>, <a href="https://publications.waset.org/abstracts/search?q=hedge" title=" hedge"> hedge</a>, <a href="https://publications.waset.org/abstracts/search?q=multivariate%20GARCH" title=" multivariate GARCH"> multivariate GARCH</a> </p> <a href="https://publications.waset.org/abstracts/20064/volatility-spillover-and-hedging-effectiveness-between-gold-and-stock-markets-evidence-for-brics-countries" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/20064.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">478</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">5437</span> Nano Gold and Silver for Control of Mosquitoes Manipulating Nanogeometries</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Soam%20Prakash">Soam Prakash</a>, <a href="https://publications.waset.org/abstracts/search?q=Namita%20Soni"> Namita Soni</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The synthesis of metallic nanoparticles is an active area of academic and more significantly, applied research in nanotechnology. Currently, nanoparticle research is an area of intense scientific interest. Silver (Ag) and Gold (Au) nanoparticles (NPs) have been the focus of fungi and plant based syntheses. Silver and gold nanoparticles are nanoparticles of silver and gold. These particles are of between 1 nm and 100 nm in size. Silver and gold have been use in the wide variety of potential applications in biomedical, optical, electronic field, treatment of burns, wounds, and several bacterial infections. There is a crucial need to produce new insecticides due to resistance and high-cost of organic insecticides which are more environmentally-friendly, safe, and target-specific. Synthesizing nanoparticles using plants and microorganisms can eliminate this problem by making the nanoparticles more biocompatible. Here we reviewed the mosquitocidal and antimicrobials activity of silver and gold nanoparticles using fungi, plants as well as bacteria. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=nano%20gold" title="nano gold">nano gold</a>, <a href="https://publications.waset.org/abstracts/search?q=nano%20silver" title=" nano silver"> nano silver</a>, <a href="https://publications.waset.org/abstracts/search?q=Malaria" title=" Malaria"> Malaria</a>, <a href="https://publications.waset.org/abstracts/search?q=Chikengunia" title=" Chikengunia"> Chikengunia</a>, <a href="https://publications.waset.org/abstracts/search?q=dengue%20control" title=" dengue control"> dengue control</a> </p> <a href="https://publications.waset.org/abstracts/28446/nano-gold-and-silver-for-control-of-mosquitoes-manipulating-nanogeometries" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/28446.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">446</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">5436</span> Optimization of Gold Adsorption from Aqua-Regia Gold Leachate Using Baggase Nanoparticles</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Oluwasanmi%20Teniola">Oluwasanmi Teniola</a>, <a href="https://publications.waset.org/abstracts/search?q=Abraham%20Adeleke"> Abraham Adeleke</a>, <a href="https://publications.waset.org/abstracts/search?q=Ademola%20Ibitoye"> Ademola Ibitoye</a>, <a href="https://publications.waset.org/abstracts/search?q=Moshood%20Shitu"> Moshood Shitu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> To establish an economical and efficient process for the recovery of gold metal from refractory gold ore obtained from Esperando axis of Osun state Nigeria, the adsorption of gold (III) from aqua reqia leached solution of the ore using bagasse nanoparticles has been studied under various experimental variables using batch technique. The extraction percentage of gold (III) on the prepared bagasse nanoparticles was determined from its distribution coefficients as a function of solution pH, contact time, adsorbent, adsorbate concentrations, and temperature. The rate of adsorption of gold (III) on the prepared bagasse nanoparticles is dependent on pH, metal concentration, amount of adsorbate, stirring rate, and temperature. The adsorption data obtained fit into the Langmuir and Freundlich equations. Three different temperatures were used to determine the thermodynamic parameters of the adsorption of gold (III) on bagasse nanoparticles. The heat of adsorption was measured to be a positive value ΔHo = +51.23kJ/mol, which serves as an indication that the adsorption of gold (III) on bagasse nanoparticles is endothermic. Also, the negative value of ΔGo = -0.6205 kJ/mol at 318K shows the spontaneity of the process. As the temperature was increased, the value of ΔGo becomes more negative, indicating that an increase in temperature favors the adsorption process. With the application of optimal adsorption variables, the adsorption capacity of gold was 0.78 mg/g of the adsorbent, out of which 0.70 mg of gold was desorbed with 0.1 % thiourea solution. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=adsorption" title="adsorption">adsorption</a>, <a href="https://publications.waset.org/abstracts/search?q=bagasse" title=" bagasse"> bagasse</a>, <a href="https://publications.waset.org/abstracts/search?q=extraction" title=" extraction"> extraction</a>, <a href="https://publications.waset.org/abstracts/search?q=nanoparticles" title=" nanoparticles"> nanoparticles</a>, <a href="https://publications.waset.org/abstracts/search?q=recovery" title=" recovery "> recovery </a> </p> <a href="https://publications.waset.org/abstracts/126039/optimization-of-gold-adsorption-from-aqua-regia-gold-leachate-using-baggase-nanoparticles" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/126039.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">161</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">5435</span> Placer Gold Deposits in Madari Gold Mine, Southern Eastern Desert, Egypt: Orientation, Source and Distribution</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Tarek%20Sedki">Tarek Sedki</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Madari gold mine is delineated by latitudes 22° 30' 29" and 22° 32' 33" N and longitudes 36° 24' 03" and 35°11' 44" E. Geologically, Madari rock units are classified into dismembered ophiolites, arc volcanic assemblage, syntectonic metagabbro-diorites and Mineralized quartz diorite and granodiorite<span dir="RTL">.</span> Deposition of gold in area occurred as a direct result of weathering of nearby gold-bearing veins. Main concentrations of gold are supposed to ensue close to the bed rock. Nevertheless, the several shallow channel-fill features covering lag deposits, arising throughout the alluvial fan sequence would definitely contain a percentage of the finer gold due to the limited washing and sorting capacity of the uncommon flood events. Gold deposits arise as disseminated and separate gold with limited pyrite, arsenopyrite and chalcopyrite everywhere veins in the wall rocks and lode gold deposits in quartz veins. In places, the wall rocks, in near district of the quartz vein, are grieved strong silicification, chloritization and pyritization as a result of a metasomatic alteration due to purification of external hydrothermal fluids. Quartz veins are mostly steeply dipping and display banding features and frequently sheared and brecciated. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Madari%20gold%20mine" title="Madari gold mine">Madari gold mine</a>, <a href="https://publications.waset.org/abstracts/search?q=placer%20deposits" title=" placer deposits"> placer deposits</a>, <a href="https://publications.waset.org/abstracts/search?q=southern%20eastern%20desert" title=" southern eastern desert"> southern eastern desert</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20mineralization" title=" gold mineralization"> gold mineralization</a>, <a href="https://publications.waset.org/abstracts/search?q=quartz%20veins" title=" quartz veins"> quartz veins</a> </p> <a href="https://publications.waset.org/abstracts/133148/placer-gold-deposits-in-madari-gold-mine-southern-eastern-desert-egypt-orientation-source-and-distribution" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/133148.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">147</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">5434</span> High Temperature in Caustic Pretreatment of Gold Locked in the Residue after Filtration from Gold Cyanidation Leaching </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=K.%20L.%20Kabemba">K. L. Kabemba</a>, <a href="https://publications.waset.org/abstracts/search?q=R.%20F.%20Sandenberg"> R. F. Sandenberg</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The usual way to desorb gold is by elution with a hot concentrated alkaline solution of sodium cyanide. The high temperature is necessary because the dielectric constant of water decreases with increasing temperature hence the electrostatic forces between charcoal and the gold cyanide complex decreases. High alkalinity and a high concentration of cyanide are necessary for gold desorption because both OH- and CN- ions are preferentially adsorbed. The rate of elution increases with increasing anion concentration but decreases with increasing cation concentration that means the rate of elution passes through a maximum as the concentration of the eluting salt (NaCN, for example) is increased. The anion that gives the best results, the cyanide ion, decomposes fairly rapidly at elevated temperatures (40% in 6 hours, 90% in 24 hours at 95°C). <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=caustic" title="caustic">caustic</a>, <a href="https://publications.waset.org/abstracts/search?q=cyanide" title=" cyanide"> cyanide</a>, <a href="https://publications.waset.org/abstracts/search?q=gold" title=" gold"> gold</a>, <a href="https://publications.waset.org/abstracts/search?q=temperature" title=" temperature"> temperature</a> </p> <a href="https://publications.waset.org/abstracts/38651/high-temperature-in-caustic-pretreatment-of-gold-locked-in-the-residue-after-filtration-from-gold-cyanidation-leaching" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/38651.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">393</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">5433</span> Preparation of Gold Nanoparticles Stabilized in Acid-Activated Montmorillonite for Nitrophenol Reduction</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Fatima%20Ammari">Fatima Ammari</a>, <a href="https://publications.waset.org/abstracts/search?q=Meriem%20Chenouf"> Meriem Chenouf</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Synthesis of gold nanoparticles (AuNPs) has attracted much attention since the pioneering discovery of the high catalytic activity of supported gold nanoparticles in the reaction of CO oxidation at low temperature. In this research field, we used montmorillonite pre-acidified under gentle conditions for AuNPs stabilization; using different loading percentage 1, 2 and 5%. The gold nanoparticles were obtained using chemical reduction method using NaBH4 as reductant agent. The obtained gold nanoparticles stabilized in acid-activated montmorillonite were used as catalysts for reduction of 4-nitrophenol to aminophenol with sodium borohydride at room temperature The UV-Vis results confirm directly the gold nanaoparticles formation. The XRD N2 adsorption and MET results showed the formation of gold nanoparticles in the pores of preacidified montmorillonite with an average size of 5.7nm. The reduction reaction of 4-nitrophenol into 4-aminophenol with NaBH4 catalyzed by Au°-montmorillonite catalyst exhibits remarkably a high activity; the reaction was completed within 4.5min. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold" title="gold">gold</a>, <a href="https://publications.waset.org/abstracts/search?q=acid-activated%20montmorillonite" title=" acid-activated montmorillonite"> acid-activated montmorillonite</a>, <a href="https://publications.waset.org/abstracts/search?q=nanoparticles" title=" nanoparticles"> nanoparticles</a>, <a href="https://publications.waset.org/abstracts/search?q=4-nitrophenol" title=" 4-nitrophenol"> 4-nitrophenol</a> </p> <a href="https://publications.waset.org/abstracts/36556/preparation-of-gold-nanoparticles-stabilized-in-acid-activated-montmorillonite-for-nitrophenol-reduction" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/36556.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">393</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">5432</span> Optimization of Gold Mining Parameters by Cyanidation</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Della%20Saddam%20Housseyn">Della Saddam Housseyn</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Gold, the quintessential noble metal, is one of the most popular metals today, given its ever-increasing cost in the international market. The Amesmessa gold deposit is one of the gold-producing deposits. The first step in our job is to analyze the ore (considered rich ore). Mineralogical and chemical analysis has shown that the general constitution of the ore is quartz in addition to other phases such as Al2O3, Fe2O3, CaO, dolomite. The second step consists of all the leaching tests carried out in rolling bottles. These tests were carried out on 14 samples to determine the maximum recovery rate and the optimum consumption of reagent (NaCN and CaO). Tests carried out on a pulp density at 50% solid, 500 ppm cyanide concentration and particle size less than 0.6 mm at alkaline pH gave a recovery rate of 94.37%. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cyanide" title="cyanide">cyanide</a>, <a href="https://publications.waset.org/abstracts/search?q=DRX" title=" DRX"> DRX</a>, <a href="https://publications.waset.org/abstracts/search?q=FX" title=" FX"> FX</a>, <a href="https://publications.waset.org/abstracts/search?q=gold" title=" gold"> gold</a>, <a href="https://publications.waset.org/abstracts/search?q=leaching" title=" leaching"> leaching</a>, <a href="https://publications.waset.org/abstracts/search?q=rate%20of%20recovery" title=" rate of recovery"> rate of recovery</a>, <a href="https://publications.waset.org/abstracts/search?q=SAA" title=" SAA"> SAA</a> </p> <a href="https://publications.waset.org/abstracts/142021/optimization-of-gold-mining-parameters-by-cyanidation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/142021.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">188</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">5431</span> Characterization of Tailings From Traditional Panning of Alluvial Gold Ore (A Case Study of Ilesa - Southwestern Nigeria Goldfield Tailings Dumps)</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Olaniyi%20Awe">Olaniyi Awe</a>, <a href="https://publications.waset.org/abstracts/search?q=Adelana%20%20R.%20Adetunji"> Adelana R. Adetunji</a>, <a href="https://publications.waset.org/abstracts/search?q=Abraham%20Adeleke"> Abraham Adeleke</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Field observation revealed a lot of artisanal gold mining activities in Ilesa gold belt of southwestern Nigeria. The possibility of alluvial and lode gold deposits in commercial quantities around this location is very high, as there are many resident artisanal gold miners who have been mining and trading alluvial gold ore for decades and to date in the area. Their major process of solid gold recovery from its ore is by gravity concentration using the convectional panning method. This method is simple to learn and fast to recover gold from its alluvial ore, but its effectiveness is based on rules of thumb and the artisanal miners' experience in handling gold ore panning tool while processing the ore. Research samples from five alluvial gold ore tailings dumps were collected and studied. Samples were subjected to particle size analysis and mineralogical and elemental characterization using X-Ray Diffraction (XRD) and Particle-Induced X-ray Emission (PIXE) methods, respectively. The results showed that the tailings were of major quartz in association with albite, plagioclase, mica, gold, calcite and sulphide minerals. The elemental composition analysis revealed a 15ppm of gold concentration in particle size fraction of -90 microns in one of the tailings dumps investigated. These results are significant. It is recommended that heaps of panning tailings should be further reprocessed using other gold recovery methods such as shaking tables, flotation and controlled cyanidation that can efficiently recover fine gold particles that were previously lost into the gold panning tailings. The tailings site should also be well controlled and monitored so that these heavy minerals do not find their way into surrounding water streams and rivers, thereby causing health hazards. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold%20ore" title="gold ore">gold ore</a>, <a href="https://publications.waset.org/abstracts/search?q=panning" title=" panning"> panning</a>, <a href="https://publications.waset.org/abstracts/search?q=PIXE" title=" PIXE"> PIXE</a>, <a href="https://publications.waset.org/abstracts/search?q=tailings" title=" tailings"> tailings</a>, <a href="https://publications.waset.org/abstracts/search?q=XRD" title=" XRD"> XRD</a> </p> <a href="https://publications.waset.org/abstracts/159275/characterization-of-tailings-from-traditional-panning-of-alluvial-gold-ore-a-case-study-of-ilesa-southwestern-nigeria-goldfield-tailings-dumps" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/159275.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">95</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">5430</span> Modified Gold Screen Printed Electrode with Ruthenium Complex for Selective Detection of Porcine DNA</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Siti%20Aishah%20Hasbullah">Siti Aishah Hasbullah</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Studies on identification of pork content in food have grown rapidly to meet the Halal food standard in Malaysia. The used mitochondria DNA (mtDNA) approaches for the identification of pig species is thought to be the most precise marker due to the mtDNA genes are present in thousands of copies per cell, the large variability of mtDNA. The standard method commonly used for DNA detection is based on polymerase chain reaction (PCR) method combined with gel electrophoresis but has major drawback. Its major drawbacks are laborious, need longer time and toxic to handle. Therefore, the need for simplicity and fast assay of DNA is vital and has triggered us to develop DNA biosensors for porcine DNA detection. Therefore, the aim of this project is to develop electrochemical DNA biosensor based on ruthenium (II) complex, [Ru(bpy)2(p-PIP)]2+ as DNA hybridization label. The interaction of DNA and [Ru(bpy)2(p-HPIP)]2+ will be studied by electrochemical transduction using Gold Screen-Printed Electrode (GSPE) modified with gold nanoparticles (AuNPs) and succinimide acrylic microspheres. The electrochemical detection by redox active ruthenium (II) complex was measured by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The results indicate that the interaction of [Ru(bpy)2(PIP)]2+ with hybridization complementary DNA has higher response compared to single-stranded and mismatch complementary DNA. Under optimized condition, this porcine DNA biosensor incorporated modified GSPE shows good linear range towards porcine DNA. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold" title="gold">gold</a>, <a href="https://publications.waset.org/abstracts/search?q=screen%20printed%20electrode" title=" screen printed electrode"> screen printed electrode</a>, <a href="https://publications.waset.org/abstracts/search?q=ruthenium" title=" ruthenium"> ruthenium</a>, <a href="https://publications.waset.org/abstracts/search?q=porcine%20DNA" title=" porcine DNA"> porcine DNA</a> </p> <a href="https://publications.waset.org/abstracts/68407/modified-gold-screen-printed-electrode-with-ruthenium-complex-for-selective-detection-of-porcine-dna" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/68407.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">312</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">5429</span> Synthesis of Biostabilized Gold Nanoparticles Using Garcinia indica Extract and Its Antimicrobial and Anticancer Properties</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Rebecca%20Thombre">Rebecca Thombre</a>, <a href="https://publications.waset.org/abstracts/search?q=Aishwarya%20Borate"> Aishwarya Borate</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Chemical synthesis of nanoparticles produces toxic by-products, as a result of which eco-friendly methods of synthesis are gaining importance. The synthesis of nanoparticles using plant derived extracts is economical, safe and eco-friendly. Biostabilized gold nanoparticles were synthesized using extracts of Garcinia indica. The gold nanoparticles were characterized using UV-Vis spectrophotometry and demonstrated a peak at 527 nm. The presence of plant derived peptides and phytoconstituents was confirmed using the FTIR spectra. TEM analysis revealed formation of gold nanopyramids and nanorods. The SAED analysis confirmed the crystalline nature of nanoparticles. The gold nanoparticles demonstrated antibacterial and antifungal activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Aspergillus niger and Pichia pastoris. The cytotoxic activity of gold nanoparticles was studied using HEK, Hela and L929 cancerous cell lines and the apoptosis of cancerous cells were observed using propidium iodide staining. Thus, a simple and eco-friendly method for synthesis of biostabilized gold nanoparticles using fruit extracts of Garcinia indica was developed and the nanoparticles had potent antibacterial, antifungal and anticancer properties. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cytotoxic" title="cytotoxic">cytotoxic</a>, <a href="https://publications.waset.org/abstracts/search?q=gold%20nanoparticles" title=" gold nanoparticles"> gold nanoparticles</a>, <a href="https://publications.waset.org/abstracts/search?q=green%20synthesis" title=" green synthesis"> green synthesis</a>, <a href="https://publications.waset.org/abstracts/search?q=Garcinia%20indica" title=" Garcinia indica"> Garcinia indica</a>, <a href="https://publications.waset.org/abstracts/search?q=anticancer" title=" anticancer"> anticancer</a> </p> <a href="https://publications.waset.org/abstracts/6347/synthesis-of-biostabilized-gold-nanoparticles-using-garcinia-indica-extract-and-its-antimicrobial-and-anticancer-properties" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/6347.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">938</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">5428</span> Rewashing for Gold: Optimizing Mine Plan for Effective Closure</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=O.%20D.%20Eniowo">O. D. Eniowo</a> </p> <p class="card-text"><strong>Abstract:</strong></p> “Rewashing” as it is commonly called, involves the process of scooping out and washing chunks of mud from a closed alluvial gold mine site with the purpose of extracting any leftover gold deposits in the site. It is usually carried out by illegal miners who infiltrate closed mine sites with the goal of scavenging for any leftover gold deposits. Expectedly, the practice gives little or no regard for environmental protection. This paper examines the process of “rewashing” in a mining community in Nigeria. It then discusses the looming danger it portends for health, safety, and the environment. The study draws lessons from these occurrences to examine and discuss fit-for-purpose mine closure plans that could be adopted by gold mines in Nigeria and other sub-Saharan African countries. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=mine%20planning" title="mine planning">mine planning</a>, <a href="https://publications.waset.org/abstracts/search?q=mine%20closure" title=" mine closure"> mine closure</a>, <a href="https://publications.waset.org/abstracts/search?q=illegal%20mining" title=" illegal mining"> illegal mining</a>, <a href="https://publications.waset.org/abstracts/search?q=artisanal%20mining" title=" artisanal mining"> artisanal mining</a>, <a href="https://publications.waset.org/abstracts/search?q=environmental%20sustainability" title=" environmental sustainability"> environmental sustainability</a> </p> <a href="https://publications.waset.org/abstracts/188429/rewashing-for-gold-optimizing-mine-plan-for-effective-closure" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/188429.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">42</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">5427</span> Assessment of Five Photoplethysmographic Methods for Estimating Heart Rate Variability</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Akshay%20B.%20Pawar">Akshay B. Pawar</a>, <a href="https://publications.waset.org/abstracts/search?q=Rohit%20Y.%20Parasnis"> Rohit Y. Parasnis</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Heart Rate Variability (HRV) is a widely used indicator of the regulation between the autonomic nervous system (ANS) and the cardiovascular system. Besides being non-invasive, it also has the potential to predict mortality in cases involving critical injuries. The gold standard method for determining HRV is based on the analysis of RR interval time series extracted from ECG signals. However, because it is much more convenient to obtain photoplethysmogramic (PPG) signals as compared to ECG signals (which require the attachment of several electrodes to the body), many researchers have used pulse cycle intervals instead of RR intervals to estimate HRV. They have also compared this method with the gold standard technique. Though most of their observations indicate a strong correlation between the two methods, recent studies show that in healthy subjects, except for a few parameters, the pulse-based method cannot be a surrogate for the standard RR interval- based method. Moreover, the former tends to overestimate short-term variability in heart rate. This calls for improvements in or alternatives to the pulse-cycle interval method. In this study, besides the systolic peak-peak interval method (PP method) that has been studied several times, four recent PPG-based techniques, namely the first derivative peak-peak interval method (P1D method), the second derivative peak-peak interval method (P2D method), the valley-valley interval method (VV method) and the tangent-intersection interval method (TI method) were compared with the gold standard technique. ECG and PPG signals were obtained from 10 young and healthy adults (consisting of both males and females) seated in the armchair position. In order to de-noise these signals and eliminate baseline drift, they were passed through certain digital filters. After filtering, the following HRV parameters were computed from PPG using each of the five methods and also from ECG using the gold standard method: time domain parameters (SDNN, pNN50 and RMSSD), frequency domain parameters (Very low-frequency power (VLF), Low-frequency power (LF), High-frequency power (HF) and Total power or “TP”). Besides, Poincaré plots were also plotted and their SD1/SD2 ratios determined. The resulting sets of parameters were compared with those yielded by the standard method using measures of statistical correlation (correlation coefficient) as well as statistical agreement (Bland-Altman plots). From the viewpoint of correlation, our results show that the best PPG-based methods for the determination of most parameters and Poincaré plots are the P2D method (shows more than 93% correlation with the standard method) and the PP method (mean correlation: 88%) whereas the TI, VV and P1D methods perform poorly (<70% correlation in most cases). However, our evaluation of statistical agreement using Bland-Altman plots shows that none of the five techniques agrees satisfactorily well with the gold standard method as far as time-domain parameters are concerned. In conclusion, excellent statistical correlation implies that certain PPG-based methods provide a good amount of information on the pattern of heart rate variation, whereas poor statistical agreement implies that PPG cannot completely replace ECG in the determination of HRV. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=photoplethysmography" title="photoplethysmography">photoplethysmography</a>, <a href="https://publications.waset.org/abstracts/search?q=heart%20rate%20variability" title=" heart rate variability"> heart rate variability</a>, <a href="https://publications.waset.org/abstracts/search?q=correlation%20coefficient" title=" correlation coefficient"> correlation coefficient</a>, <a href="https://publications.waset.org/abstracts/search?q=Bland-Altman%20plot" title=" Bland-Altman plot"> Bland-Altman plot</a> </p> <a href="https://publications.waset.org/abstracts/38739/assessment-of-five-photoplethysmographic-methods-for-estimating-heart-rate-variability" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/38739.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">326</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">5426</span> Effect of III-V Nitrides on Performance of Graphene-Gold SPR Biosensor</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Bijaya%20Kumar%20Sahoo">Bijaya Kumar Sahoo</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The effect of III-V nitride semiconductors on performance of a graphene-on-gold surface plasmon resonance (SPR) biosensor has been investigated theoretically. III-V nitrides (AlN, GaN and InN) have been grown between gold (Au) and graphene layers. The sensitivity and performance of the biosensor have been computed for with and without semiconductors. Due to superior electronic and optical properties, III-V nitrides demonstrate high sensitivity and performance over Si and Ge. The enhancement of evanescent electric field due to III-V nitrides have been computed and found highest for InN. The analysis shows that for a high-sensitive imaging biosensor the required optimal thickness of gold, InN and graphene are respectively 49 nm, 11 nm and 0.34 nm for the light of wavelength =633 nm (red He-Ne laser). This study suggests that InN would be a better choice for fabrication of new imaging SPR biosensors. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=SPR%20biosensor" title="SPR biosensor">SPR biosensor</a>, <a href="https://publications.waset.org/abstracts/search?q=optical%20properties" title=" optical properties"> optical properties</a>, <a href="https://publications.waset.org/abstracts/search?q=III-V%20nitrides" title=" III-V nitrides"> III-V nitrides</a>, <a href="https://publications.waset.org/abstracts/search?q=sensitivity" title=" sensitivity"> sensitivity</a>, <a href="https://publications.waset.org/abstracts/search?q=enhancement%20of%20electric%20field" title=" enhancement of electric field"> enhancement of electric field</a>, <a href="https://publications.waset.org/abstracts/search?q=performance%20of%20graphene%20gold%20SPR%20biosensor" title=" performance of graphene gold SPR biosensor"> performance of graphene gold SPR biosensor</a> </p> <a href="https://publications.waset.org/abstracts/46349/effect-of-iii-v-nitrides-on-performance-of-graphene-gold-spr-biosensor" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/46349.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">554</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">5425</span> Characterization of Complex Gold Ores for Preliminary Process Selection: The Case of Kapanda, Ibindi, Mawemeru, and Itumbi in Tanzania</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sospeter%20P.%20Maganga">Sospeter P. Maganga</a>, <a href="https://publications.waset.org/abstracts/search?q=Alphonce%20Wikedzi"> Alphonce Wikedzi</a>, <a href="https://publications.waset.org/abstracts/search?q=Mussa%20D.%20Budeba"> Mussa D. Budeba</a>, <a href="https://publications.waset.org/abstracts/search?q=Samwel%20V.%20Manyele"> Samwel V. Manyele</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study characterizes complex gold ores (elemental and mineralogical composition, gold distribution, ore grindability, and mineral liberation) for preliminary process selection. About 200 kg of ore samples were collected from each location using systematic sampling by mass interval. Ores were dried, crushed, milled, and split into representative sub-samples (about 1 kg) for elemental and mineralogical composition analyses using X-ray fluorescence (XRF), fire assay finished with Atomic Absorption Spectrometer (AAS), and X-ray Diffraction (XRD) methods, respectively. The gold distribution was studied on size-by-size fractions, while ore grindability was determined using the standard Bond test. The mineral liberation analysis was conducted using ThermoFisher Scientific Mineral Liberation Analyzer (MLA) 650, where unsieved polished grain mounts (80% passing 700 µm) were used as MLA feed. Two MLA measurement modes, X-ray modal analysis (XMOD) and sparse phase liberation-grain X-ray mapping analysis (SPL-GXMAP), were employed. At least two cyanide consumers (Cu, Fe, Pb, and Zn) and kinetics impeders (Mn, S, As, and Bi) were present in all locations investigated. Copper content at Kapanda (0.77% Cu) and Ibindi (7.48% Cu) exceeded the recommended threshold of 0.5% Cu for direct cyanidation. The gold ore at Ibindi indicated a higher rate of grinding compared to other locations. This could be explained by the highest grindability (2.119 g/rev.) and lowest Bond work index (10.213 kWh/t) values. The pyrite-marcasite, chalcopyrite, galena, and siderite were identified as major gold, copper, lead, and iron-bearing minerals, respectively, with potential for economic extraction. However, only gold and copper can be recovered under conventional milling because of grain size issues (galena is exposed by 10%) and process complexity (difficult to concentrate and smelt iron from siderite). Therefore, the preliminary process selection is copper flotation followed by gold cyanidation for Kapanda and Ibindi ores, whereas gold cyanidation with additives such as glycine or ammonia is selected for Mawemeru and Itumbi ores because of low concentrations of Cu, Pb, Fe, and Zn minerals. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=complex%20gold%20ores" title="complex gold ores">complex gold ores</a>, <a href="https://publications.waset.org/abstracts/search?q=mineral%20liberation" title=" mineral liberation"> mineral liberation</a>, <a href="https://publications.waset.org/abstracts/search?q=ore%20characterization" title=" ore characterization"> ore characterization</a>, <a href="https://publications.waset.org/abstracts/search?q=ore%20grindability" title=" ore grindability"> ore grindability</a> </p> <a href="https://publications.waset.org/abstracts/166554/characterization-of-complex-gold-ores-for-preliminary-process-selection-the-case-of-kapanda-ibindi-mawemeru-and-itumbi-in-tanzania" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/166554.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">76</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">5424</span> Fluorescent Analysis of Gold Nanoclusters-Wool Keratin Addition to Copper Ions</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Yao%20Xing">Yao Xing</a>, <a href="https://publications.waset.org/abstracts/search?q=Hong%20Ling%20Liu"> Hong Ling Liu</a>, <a href="https://publications.waset.org/abstracts/search?q=Wei%20Dong%20Yu"> Wei Dong Yu</a> </p> <p class="card-text"><strong>Abstract:</strong></p> With the increase of global population, it is of importance for the safe water supply, while, the water-monitoring method with the capability of rapidness, low-cost, green and robustness remains unsolved. In this paper, gold nanoclusters-wool keratin is added into copper ions measured by fluorescent method in order to probe copper ions in aqueous solution. The fluorescent results show that gold nanoclusters-wool keratin exhibits high stability of pHs, while it is sensitive to temperature and time. Based on Gauss fitting method, the results exhibit that the slope of gold nanoclusters-wool keratin with pH resolution under acidic condition is higher compared to it under alkaline solutions. Besides, gold nanoclusters-wool keratin added into copper ions shows a fluorescence turn-off response transferring from red to blue under UV light, leading to the dramatically decreased fluorescent intensity of gold nanoclusters-wool keratin solution located at 690 nm. Moreover, the limited concentration of copper ions tested by gold nanoclusters-wool keratin system is around 1 µmol/L, which meets the need of detection standards. The fitting slope of Stern-Volmer plot at low concentration of copper ions is larger than it at high concentrations, which indicates that aggregated gold nanoclusters are from small amounts to large numbers with the increasing concentration of copper ions. It is expected to provide novel method and materials for copper ions testing with low cost, high efficiency, and easy operability. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold%20nanoclusters" title="gold nanoclusters">gold nanoclusters</a>, <a href="https://publications.waset.org/abstracts/search?q=copper%20ions" title=" copper ions"> copper ions</a>, <a href="https://publications.waset.org/abstracts/search?q=wool%20keratin" title=" wool keratin"> wool keratin</a>, <a href="https://publications.waset.org/abstracts/search?q=fluorescence" title=" fluorescence"> fluorescence</a> </p> <a href="https://publications.waset.org/abstracts/87828/fluorescent-analysis-of-gold-nanoclusters-wool-keratin-addition-to-copper-ions" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/87828.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">261</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">5423</span> Chemical Synthesis, Electrical and Antibacterial Properties of Polyaniline/Gold Nanocomposites</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=L.%20N.%20Shubha">L. N. Shubha</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Kalpana"> M. Kalpana</a>, <a href="https://publications.waset.org/abstracts/search?q=P.%20Madhusudana%20Rao"> P. Madhusudana Rao</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Polyaniline/gold (PANI/Au) nanocomposite was prepared by in-situ chemical oxidation polymerization method. The synthesis involved the formation of polyaniline-gold nanocomposite, by in-situ redox reaction and the dispersion of gold nano particles throughout the polyaniline matrix. The nanocomposites were characterized by XRD, FTIR, TEM and UV-visible spectroscopy. The characteristic peaks in FTIR and UV-visible spectra confirmed the expected structure of polymer as reported in the literature. Further, transmission electron microscopy (TEM) confirmed the formation of gold nano particles. The crystallite size of 30 nm for nanoAu was supported by the XRD pattern. Further, the A.C. conductivity, dielectric constant (€’(w)) and dielectric loss (€’’(w)) of PANI/Au nano composite was measured using impedance analyzer. The effect of doping on the conductivity was investigated. The antibacterial activity was examined for this nano composite and it was observed that PANI/Au nanocomposite could be used as an antibacterial agent. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=AC-conductivity" title="AC-conductivity">AC-conductivity</a>, <a href="https://publications.waset.org/abstracts/search?q=anti-microbial%20activity" title=" anti-microbial activity"> anti-microbial activity</a>, <a href="https://publications.waset.org/abstracts/search?q=dielectric%20constant" title=" dielectric constant"> dielectric constant</a>, <a href="https://publications.waset.org/abstracts/search?q=dielectric%20loss" title=" dielectric loss"> dielectric loss</a>, <a href="https://publications.waset.org/abstracts/search?q=polyaniline%2Fgold%20%28PANI%2FAU%29%20nanocomposite" title=" polyaniline/gold (PANI/AU) nanocomposite "> polyaniline/gold (PANI/AU) nanocomposite </a> </p> <a href="https://publications.waset.org/abstracts/15221/chemical-synthesis-electrical-and-antibacterial-properties-of-polyanilinegold-nanocomposites" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/15221.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">389</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">5422</span> Review on Green Synthesis of Gold Nanoparticles</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shabnam">Shabnam</a>, <a href="https://publications.waset.org/abstracts/search?q=Jagdeep%20Kumar"> Jagdeep Kumar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Because of the impact of their greater surface area and smaller quantum sizes in comparison with other metal atoms or bulk metals, metal nanoparticles, such as those formed of gold, exhibit a variety of unusual chemical and physical properties. The size- and shape-dependent properties of gold nanoparticles (GNPs) are particularly notable. Metal nanoparticles have received a lot of attention due to their unique properties and exciting prospective uses in photonics, electronics, biological sensing, and imaging. The latest developments in GNP synthesis are discussed in this review. Green chemistry measures were used to assess the production of gold nanoparticles, with a focus on Process Mass Intensity (PMI). Based on these measurements, opportunities for improving synthetic approaches were found. With PMIs that were often in the thousands, solvent usage was found to be the main obstacle for nanoparticle synthesis, even ones that were otherwise considered to be environmentally friendly. Since ligated metal nanoparticles are the most industrially relevant but least environmentally friendly, their synthesis by arrested precipitation was chosen as the best chance for significant advances. Gold nanoparticles of small sizes and bio-stability are produced biochemically, and they are used in many biological applications. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold" title="gold">gold</a>, <a href="https://publications.waset.org/abstracts/search?q=nanoparticles" title=" nanoparticles"> nanoparticles</a>, <a href="https://publications.waset.org/abstracts/search?q=green%20synthesis" title=" green synthesis"> green synthesis</a>, <a href="https://publications.waset.org/abstracts/search?q=AuNP" title=" AuNP"> AuNP</a> </p> <a href="https://publications.waset.org/abstracts/165149/review-on-green-synthesis-of-gold-nanoparticles" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/165149.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">87</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">5421</span> Clean Gold Solution from Printed Circuit Board Physical Processing Dust by Selective Complexation</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Iyiola%20O.%20Otunniyi">Iyiola O. Otunniyi</a>, <a href="https://publications.waset.org/abstracts/search?q=Oluwayimika%20O.%20Oluokun"> Oluwayimika O. Oluokun</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The two-step leaching process of PCB dust will produce a first leaching stream containing assorted metals that still requires more demanding multistage processing afterward to recover base metals and precious metals. In this work, three-step selective complexations produce a clean gold solution from printed circuit board dust. After optimizing for temperature and concentrations, the first step under oxidative ammonia leaching recovered no gold, 90 % Cu and 50 % Zn. Second step acid leaching recovered no gold, 89 % Fe, 48 % Zn, 94 % Ni. The recoveries generally increased with reducing dust particle sizes, except for zinc under oxidative ammonia, and it was noted that its various alloy forms in PCB could be responsible for this. At the third leaching step using acidified thiourea with 0.1 M H₂O₂ at 25 OC, gold recovery was 99 %. The leaching rate was shown to be chemically controlled, implying that reagent dosage control will compensate for feed assay shifts in an operation design. Copper, zinc and nickel will be easily recoverable from leach solutions of the first two steps in this leaching scheme. The third step produced a clean gold solution for easy processing downstream. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=gold%20thiourea%20complexation" title="gold thiourea complexation">gold thiourea complexation</a>, <a href="https://publications.waset.org/abstracts/search?q=printed%20circuit%20board" title=" printed circuit board"> printed circuit board</a>, <a href="https://publications.waset.org/abstracts/search?q=step%20leaching" title=" step leaching"> step leaching</a>, <a href="https://publications.waset.org/abstracts/search?q=selective%20recovery" title=" selective recovery"> selective recovery</a> </p> <a href="https://publications.waset.org/abstracts/195407/clean-gold-solution-from-printed-circuit-board-physical-processing-dust-by-selective-complexation" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/195407.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">19</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">5420</span> A Dihydropyridine Derivative as a Highly Selective Fluorometric Probe for Quantification of Au3+ Residue in Gold Nanoparticle Solution</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Waroton%20Paisuwan">Waroton Paisuwan</a>, <a href="https://publications.waset.org/abstracts/search?q=Mongkol%20Sukwattanasinitt"> Mongkol Sukwattanasinitt</a>, <a href="https://publications.waset.org/abstracts/search?q=Mamoru%20Tobisu"> Mamoru Tobisu</a>, <a href="https://publications.waset.org/abstracts/search?q=Anawat%20Ajavakom"> Anawat Ajavakom</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Novel dihydroquinoline derivatives (DHP and DHP-OH) were synthesized in one pot via a tandem trimerization-cyclization of methylpropiolate. DHP and DHP-OH possess strong blue fluorescence with high quantum efficiencies over 0.70 in aqueous media. DHP-OH displays a remarkable fluorescence quenching selectively to the presence of Au3+ through the oxidation of dihydropyridine to pyridinium ion as confirmed by NMR and HRMS. DHP-OH was used to demonstrate the quantitative analysis of Au3+ in water samples with the limit of detection of 33 ppb and excellent recovery (>95%). This fluorescent probe was also applied for the determination of Au3+ residue in the gold nanoparticle solution and a paper-based sensing strip for the on-site detection of Au3+. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Gold%28III%29%20ion%20detection" title="Gold(III) ion detection">Gold(III) ion detection</a>, <a href="https://publications.waset.org/abstracts/search?q=Fluorescent%20sensor" title=" Fluorescent sensor"> Fluorescent sensor</a>, <a href="https://publications.waset.org/abstracts/search?q=Fluorescence%20quenching" title=" Fluorescence quenching"> Fluorescence quenching</a>, <a href="https://publications.waset.org/abstracts/search?q=Dihydropyridine" title=" Dihydropyridine"> Dihydropyridine</a>, <a href="https://publications.waset.org/abstracts/search?q=Gold%20nanoparticles%20%28AuNPs%29" title=" Gold nanoparticles (AuNPs)"> Gold nanoparticles (AuNPs)</a> </p> <a href="https://publications.waset.org/abstracts/165620/a-dihydropyridine-derivative-as-a-highly-selective-fluorometric-probe-for-quantification-of-au3-residue-in-gold-nanoparticle-solution" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/165620.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">93</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">5419</span> Measurement of eGFR in pregnancy: Serum Creatinine-Based Alternative to 24-Hour-Urine Creatinine Clearance</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Amita%20Pandey%20Mishra">Amita Pandey Mishra</a>, <a href="https://publications.waset.org/abstracts/search?q=Priya%20Agarwal"> Priya Agarwal</a>, <a href="https://publications.waset.org/abstracts/search?q=Anupma%20Kaul"> Anupma Kaul</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Background Pre-existing or new-onset renal dysfunction is common in hypertensive disorders & high risk pregnancies. Estimated Glomerular Filtration Rate (eGFR) is a key indicator for kidney dysfunction. Abnormal eGFR in midterm pregnancy is known to be associated with adverse pregnancy outcomes. The Gold standard for measurement of eGFR is 24-hr urine creatinine clearance but collection of 24-hr urine is cumbersome & inconvenient. We compared the diagnostic accuracy of serum creatinine based eGFR estimation methods (CKD-EPI, MDRD, NANRA) with the gold standard in pregnant women. Method 144 pregnant women were registered in this diagnostic study from antenatal OPD of a Tertiary care Hospital in North India after excluding renal & immunological diseases. Between 14-28 weeks gestation, each participant collected a 24-hour urine sample for measurement of 24-hr-urine creatinine clearance. Simultaneously, 2 ml blood sample was taken to measure serum creatinine from which eGFR was calculated using CKD-EPI, MDRD, and NANRA formulae. All women were followed till delivery for development of pregnancy related complications. Results The mean eGFR measured by 24-hour-urine creatinine clearance in 144 pregnant women was 119 ± 27.89 mL/min/1.73m². All serum creatinine-based methods underestimated eGFR, with CKD-EPI averaging 111.33 ± 31.45 mL/min/1.73m², NANRA 105.58 ± 30.10 mL/min/1.73m² and MDRD 101.74 ± 32.34 mL/min/1.73m². Pearson’s Correlation coefficient was highest for CKD-EPI (0.789), followed by NANRA (0.771) and MDRD (0.744) indicating its strong correlation with the gold standard. 35.4% women had lower than normal eGFR and on follow-up, they had significantly more complications like preeclampsia, fetal growth restriction, preterm delivery, intrauterine death and renal dysfunction requiring treatment. ROC curve of eGFR to predict pregnancy complications showed the best diagnostic accuracy of gold standard followed by CKDEPI method. Conclusion Measurement of midterm eGFR in pregnancy allows early identification of renal dysfunction in pregnancy and can predict serious pregnancy related complications. CKD-EPI is a feasible, convenient, relatively accurate alternative to 24-hr-urine creatinine clearance for measuring eGFR in pregnancy which can be easily integrated in routine obstetric care. It is also a promising biomarker to predict pregnancy outcome and risk of long term renal dysfunction. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=eGFR" title="eGFR">eGFR</a>, <a href="https://publications.waset.org/abstracts/search?q=urine%20creatinine%20clearance" title=" urine creatinine clearance"> urine creatinine clearance</a>, <a href="https://publications.waset.org/abstracts/search?q=CKD-EPI" title=" CKD-EPI"> CKD-EPI</a>, <a href="https://publications.waset.org/abstracts/search?q=pregnancy%20outcome" title=" pregnancy outcome"> pregnancy outcome</a> </p> <a href="https://publications.waset.org/abstracts/198687/measurement-of-egfr-in-pregnancy-serum-creatinine-based-alternative-to-24-hour-urine-creatinine-clearance" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/198687.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">3</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">5418</span> The Effect of Artificial Intelligence on Decoration Designs</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ayed%20Mouris%20Gad%20Elsayed%20Khalil">Ayed Mouris Gad Elsayed Khalil</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This research focuses on historical techniques associated with the Lajevardin and Haft-Rangi production methods in tile production, with particular attention to identifying techniques for applying gold leaf to the surface of these historical glazed tiles. In this context, the history of the production of glazed, gilded and glazed Lajevardin ceramics from the Khwarizmanshahid and Mongol periods (11th to 13th centuries) was first evaluated in order to better understand the context and history of the methods of historical enameling. After a historical overview of glazed ceramic production techniques and the adoption of these techniques by civilizations, we focused on the niche production methods of glazes and Lajevardin glazes, two categories of decoration commonly found on tiles. A general method for classifying the different types of gold tiles was then introduced, applicable to tiles from to the Safavid period (16th-17th centuries). These categories include gold glazed Lajevardina tiles, haft rangi gold tiles, gold glazed monolithic tiles and gold mosaic tiles. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=ethnicity" title="ethnicity">ethnicity</a>, <a href="https://publications.waset.org/abstracts/search?q=multi-cultural" title=" multi-cultural"> multi-cultural</a>, <a href="https://publications.waset.org/abstracts/search?q=jewelry" title=" jewelry"> jewelry</a>, <a href="https://publications.waset.org/abstracts/search?q=craft%20techniquemycenaean" title=" craft techniquemycenaean"> craft techniquemycenaean</a>, <a href="https://publications.waset.org/abstracts/search?q=ceramic" title=" ceramic"> ceramic</a>, <a href="https://publications.waset.org/abstracts/search?q=provenance" title=" provenance"> provenance</a>, <a href="https://publications.waset.org/abstracts/search?q=pigmentAmorium" title=" pigmentAmorium"> pigmentAmorium</a>, <a href="https://publications.waset.org/abstracts/search?q=glass%20bracelets" title=" glass bracelets"> glass bracelets</a>, <a href="https://publications.waset.org/abstracts/search?q=image" title=" image"> image</a>, <a href="https://publications.waset.org/abstracts/search?q=Byzantine%20empire" title=" Byzantine empire"> Byzantine empire</a> </p> <a href="https://publications.waset.org/abstracts/184426/the-effect-of-artificial-intelligence-on-decoration-designs" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/184426.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">66</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" 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