The National Academies Press

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width: 24px; } .controls__search, .controls__menu, .controls__nav { font-size: 12px; } .global-nav__menus--upper { display: -webkit-flex; display: flex; -webkit-justify-content: space-between; justify-content: space-between; margin-bottom: 2rem; } .global-nav__link { font-size: 16px; } .global-nav__links ul { display: -webkit-flex; display: flex; -webkit-justify-content: flex-end; justify-content: flex-end; margin-top: 5px; list-style: none; } .invert { background: #000; color: #fff; } .controls__nav .menu-off { display: inline; } .controls__nav .menu-on { display: none; } .controls__nav.invert .menu-off { display: none } .controls__nav.invert .menu-on { display: inline; } .mega-menu { background-color: rgb(243, 241, 235); background-color: var(--color-brown--bone); position: fixed; top: 0; right: 0; bottom: 0; left: 0; overflow: scroll; z-index: 9999999; } .mega-menu .mega-menu__header { display: -webkit-flex; display: flex; -webkit-justify-content: space-between; justify-content: space-between; -webkit-align-items: center; align-items: center; padding-top: 1rem; } .mega-menu__content .search-form__container { position: relative; max-width: 70em; margin: 0 auto; } #search .global-nav__logo { position: absolute; top: 1em; } .sf-top { margin-top: 50px; } #searchFormNAP { display: block; height: 100px; } a:hover, a:focus { color: #1C143D; text-decoration: underline; } #fixedfooter a:hover, #fixedfooter a:focus { color: #fff; text-decoration: underline; } .btn-blueflat.btn-searchhome.hide-xs { display: none; } .mega-menu__content { margin-top: 50px; margin-left: 7px; } .accordion__title.faq__accordion__title .flex.justify-between { display: inherit; } .global-nav__logo { margin: 0px !important; position: absolute; left: 15px; top: 25px; height: 55px; } .global-nav__link:hover { text-decoration: none; } @media screen and (min-width: 65em) { .mega-menu__content .search-form { padding: 1em 0px 3em 0em; } } @media (min-width: 45rem) { .global-nav__logo {} } @media (max-width: 480px) { .global-nav__logo { margin: 0px !important; position: absolute; left: 15px; top: 12px; } } /* Style the buttons that are used to open and close the accordion panel */ #mobile-menu button.accordion, #mobile-menu button.no-accordion { letter-spacing: 1px; text-align: left; color: #4148C2; font-size: 1.1em; font-weight: 700 !important; font-family: 'lato', helvetica, sans-serif; padding: 15px 0px 15px 0px; border-top: none !important; border-bottom: .5px solid rgb(221, 213, 199) !important; cursor: pointer; width: 100%; } .mega-menu__content .accordion { border: 0; font-weight: 700; } #mobile-menu .accordion:after { content: '\02795'; /* Unicode character for "plus" sign (+) */ font-size: 13px; color: #777; float: right; margin-left: 5px; } #mobile-menu button.active:after { content: "\2796"; /* Unicode character for "minus" sign (-) */ } /* Add a background color to the button if it is clicked on (add the .active class with JS), and when you move the mouse over it (hover) */ #mobile-menu button.active, #mobile-menu button.accordion:hover { background-color: transparent; } /* Style the accordion panel. Note: hidden by default */ #mobile-menu .panel { padding: 0 0; background-color: transparent; max-height: 0; box-shadow: 0 !important; overflow: hidden; transition: max-height 0.2s ease-out; margin: 0px !important; border: 0 !important; } #mobile-menu .panel ul li { margin: 0px 0px; padding-left: 0px; } #mobile-menu .panel ul { margin-top: 10px; margin-bottom: 10px; padding-left: 0px; } #mobile-menu .panel ul li { line-height: 2; } #mobile-menu .panel ul li a { color: #000; text-decoration: underline; cursor: pointer; } .controls__menu-mobile { text-transform: uppercase; } .controls__menu-mobile svg { fill: #222; fill: var(--color-neutral--charcoal); width: 1.75rem; height: 1.75rem; } .cart-badge { display: inline-block; text-align: center; line-height: 1; background: #7899F2; color: white; font-weight: bold; border-radius: 20px; padding: 3px 6px; margin-left: 3px; } @media screen and (min-width: 65em) { #mobile-menu .controls__menu { display: inline; } } @media screen and (max-width: 65em) { #mobile-menu .controls__menu svg { display: inline; } } /*NAP mega menu dropdown*/ li.nap-mega-menu.mega-dropdown { position: static !important; width:100% !important; } .nap-mega-menu .mega-dropdown-menu { padding: 20px 0px; box-shadow: none; -webkit-box-shadow: none; margin-top: 10px !important; box-shadow: 0 5px 15px var(--box-shadow--charcoal); transform: none !important; top: 100% !important; } .nap-mega-menu .mega-dropdown-menu > li > ul.browse-col { padding: 0; margin: 0; width: 100%; } .nap-mega-menu .mega-dropdown-menu > li > ul > li { list-style: none; } .nap-mega-menu .mega-dropdown-menu > li > ul > li > a { display: block; padding: 3px 20px; clear: both; font-weight: normal; line-height: 1.428571429; color: #4148C2; white-space: normal; font-size: 14px; text-transform: none; } .nap-mega-menu .mega-dropdown-menu > li ul > li > a:hover, .nap-mega-menu .mega-dropdown-menu > li ul > li > a:focus { text-decoration: none; color: #444; background-color: #f5f5f5; } .nap-mega-menu .mega-dropdown-menu .dropdown-header a { color: #4148C2; font-size: 14px; font-weight: 900 !important; text-align: left; text-transform: uppercase !important; padding: 0px; margin-bottom: 7px; } .nap-mega-menu .mega-dropdown-menu form { margin:3px 20px; } .nap-mega-menu .mega-dropdown-menu .form-group { margin-bottom: 3px; } .nap-mega-menu .vertical-divider { border-left: 1px solid #ccc; } .nap-mega-menu .mega-dropdown-menu > li.d-flex { display: inline-flex !important; margin-right: 0 !important; justify-content: space-between; flex-wrap: nowrap !important; flex-direction: row !important; } #nap-mega-menu-inner { justify-content: space-between; align-content:start; } #nap-mega-menu-inner li.browse-col { width: 22%; } </style> <header class="global-nav global-nav--local menu-is-hidden search-is-hidden" id="lowerMenu"> <div class="container flex justify-between">  <div aria-hidden="true" class="mega-menu" id="search"> <div data-lock=""> <div class="container 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proceedings of the fifteenth meeting of the Army-Navy-NRC Vision Committee: 12-13 February, 1946, National Academy of Sciences, Washington, D.C." data-alias="title">Minutes and proceedings of the fifteenth meeting of the Army-Navy-NRC Vision Committee: 12-13 February, 1946, National Academy of Sciences, Washington, D.C.</a></h4> </div> </div> </div> </div> </div> </section> <section class="bottom-rows"> <div class="container sc">  <div class="sc-row row" data-title="Searchable Collections"> <div class="col-md-10"> <h2 class="sc row-title">Searchable Collections <a href="/collection" class="sc-more nr-vm pull-right">more<span class="arrow"></span></a></h2> </div> <div class="sc-tile col-sm-2 col-xs-5 col-sc "> <div class="sc-outer" style="background: #fff url(https://nap.nationalacademies.org/images/collections/95.png) no-repeat center 24px;" data-alias="image"> <div class="sc-inner"> <h4 class="sc" data-alias="title">Crisis Standards of Care</h4> <p class="truncate sc-desc " data-alias="description">Public health disasters justify temporarily adjusting practice standards and/or shifting the balance of ethical concerns to emphasize the needs of the community rather than the needs of individuals. Our Crisis Standards of Care publications provide guidance for use by state and local public health officials and health-sector agencies and institutions in establishing and implementing standards of care that should apply in disaster situations.</p> <p class="sc-link"><a href="https://nap.nationalacademies.org/collection/95/crisis-standards-of-care" data-alias="view all" data-title="Crisis Standards of Care">View all titles</a></p> </div> </div> </div> <div class="sc-tile col-sm-2 col-xs-5 col-sc "> <div class="sc-outer" style="background: #fff url(https://nap.nationalacademies.org/images/collections/34.png) no-repeat center 24px;" data-alias="image"> <div class="sc-inner"> <h4 class="sc" data-alias="title">Climate Change</h4> <p class="truncate sc-desc " data-alias="description">Climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems. 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This collection emphasizes the importance of 21st century choices regarding long-term climate stabilization through improving understanding of the causes and consequences of climate change and expanding the options available to limit the magnitude of climate change.</p> <p class="sc-link"><a href="https://nap.nationalacademies.org/collection/34/climate-change" data-alias="view all" data-title="Climate Change">View all titles</a></p> </div> </div> </div> <div class="sc-tile col-sm-2 col-xs-5 col-sc "> <div class="sc-outer" style="background: #fff url(https://nap.nationalacademies.org/images/collections/35.png) no-repeat center 24px;" data-alias="image"> <div class="sc-inner"> <h4 class="sc" data-alias="title">Emergency Preparedness / Disaster Management</h4> <p class="truncate sc-desc " data-alias="description">Even prepared communities can be overwhelmed in a state of state of emergency. 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As new infectious diseases are continuing to emerge in new locations around the globe, it is essential society understands the environmental, human health, and ecological impacts cause by infectious diseases. This collection provides an overview of infectious disease, including the biology, history, the future trends of widespread and harmful infections, and what we need to do individually, and as a society, to address this growing global challenge.</p> <p class="sc-link"><a href="https://nap.nationalacademies.org/collection/37/infectious-disease" data-alias="view all" data-title="Infectious Disease">View all titles</a></p> </div> </div> </div> <div class="sc-tile col-sm-2 col-xs-5 col-sc hidden-xs"> <div class="sc-outer" style="background: #fff url(https://nap.nationalacademies.org/images/collections/94.png) no-repeat center 24px;" data-alias="image"> <div class="sc-inner"> <h4 class="sc" data-alias="title">Coronavirus Resources</h4> <p class="truncate sc-desc sc-desclast " data-alias="description">This collection is a compilation of our resources related to COVID-19. 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