PNAS.ORG PNAS

pnas.org Website Information

Daily Unique Visits: 3,725,834

Daily Page Views: 29,806,672

Income Per Day: $29,807

Estimated Value: $32,191,560

This website is located in United States and is using following IP address 104.18.33.155. See the complete list of popular websites hosted in United States.

pnas.org is registered under .ORG top-level domain. Please check other sites in .ORG zone.

Website pnas.org is using the following name servers:

  • ishaan.ns.cloudflare.com
  • saanvi.ns.cloudflare.com

and is probably hosted by CLOUDFLARENET - Cloudflare, Inc., US. See the full list of other websites hosted by CLOUDFLARENET - Cloudflare, Inc., US.

The highest website pnas.org position in Alexa rank database was 398 and the lowest rank position was 419. Current position of pnas.org in Alexa rank database is 409.

Desktop speed score of pnas.org (61/100) is better than the results of 37.05% of other sites and shows that the page desktop performance can be improved.

Mobile usability score of pnas.org (96/100) is better than the results of 46.59% of other sites and means that the page is mobile-friendly.

Mobile speed score of pnas.org (47/100) is better than the results of 28.68% of other sites and shows that the landing page performance on mobile devices is poor and can be improved.

Advertisement

pnas.org Alexa Rank

The traffic rank is based on three months of aggregated historical traffic data from millions of Alexa Toolbar users and is a combined measure of page views and users.


pnas.org whois

WHOIS gives you the ability to lookup any generic domains to find out the registered domain holder. WHOIS database are provided for information purposes only. It allows the public to check whether a specific domain name is still available or not and to obtain information related to the registration records of existing domain names.


Domain Name: pnas.org
Registry Domain ID: db6de56097a2428e9f5172ba44a93b47-LROR
Registrar WHOIS Server: whois.networksolutions.com
Registrar URL: http://www.networksolutions.com
Updated Date: 2023-03-26T14:01:19Z
Creation Date: 1996-03-23T05:00:00Z
Registry Expiry Date: 2028-03-24T05:00:00Z
Registrar: Network Solutions, LLC
Registrar IANA ID: 2
Registrar Abuse Contact Email: domain.operations@web.com
Registrar Abuse Contact Phone: +1.8777228662
Domain Status: clientTransferProhibited https://icann.org/epp#clientTransferProhibited
Registry Registrant ID: REDACTED FOR PRIVACY
Registrant Name: REDACTED FOR PRIVACY
Registrant Organization: National Academy of Sciences
Registrant Street: REDACTED FOR PRIVACY
Registrant City: REDACTED FOR PRIVACY
Registrant State/Province: DC
Registrant Postal Code: REDACTED FOR PRIVACY
Registrant Country: US
Registrant Phone: REDACTED FOR PRIVACY
Registrant Phone Ext: REDACTED FOR PRIVACY
Registrant Fax: REDACTED FOR PRIVACY
Registrant Fax Ext: REDACTED FOR PRIVACY
Registrant Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Registry Admin ID: REDACTED FOR PRIVACY
Admin Name: REDACTED FOR PRIVACY
Admin Organization: REDACTED FOR PRIVACY
Admin Street: REDACTED FOR PRIVACY
Admin City: REDACTED FOR PRIVACY
Admin State/Province: REDACTED FOR PRIVACY
Admin Postal Code: REDACTED FOR PRIVACY
Admin Country: REDACTED FOR PRIVACY
Admin Phone: REDACTED FOR PRIVACY
Admin Phone Ext: REDACTED FOR PRIVACY
Admin Fax: REDACTED FOR PRIVACY
Admin Fax Ext: REDACTED FOR PRIVACY
Admin Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Registry Tech ID: REDACTED FOR PRIVACY
Tech Name: REDACTED FOR PRIVACY
Tech Organization: REDACTED FOR PRIVACY
Tech Street: REDACTED FOR PRIVACY
Tech City: REDACTED FOR PRIVACY
Tech State/Province: REDACTED FOR PRIVACY
Tech Postal Code: REDACTED FOR PRIVACY
Tech Country: REDACTED FOR PRIVACY
Tech Phone: REDACTED FOR PRIVACY
Tech Phone Ext: REDACTED FOR PRIVACY
Tech Fax: REDACTED FOR PRIVACY
Tech Fax Ext: REDACTED FOR PRIVACY
Tech Email: Please query the RDDS service of the Registrar of Record identified in this output for information on how to contact the Registrant, Admin, or Tech contact of the queried domain name.
Name Server: ishaan.ns.cloudflare.com
Name Server: saanvi.ns.cloudflare.com
DNSSEC: unsigned
URL of the ICANN Whois Inaccuracy Complaint Form: https://www.icann.org/wicf/
>>> Last update of WHOIS database: 2023-10-15T07:15:22Z

pnas.org server information

Servers Location

pnas.org desktop page speed rank

Last tested: 2017-05-04


Desktop Speed Bad
61/100

pnas.org Desktop Speed Test Quick Summary


priority - 33Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

http://pnas-movie.glencoesoftware.com/static/video-js.min.css (expiration not specified)
http://pnas-movie.glencoesoftware.com/static/video_inline.min.js (expiration not specified)
http://www.pnas.org/local/img/nav/background-expand-lg.png (expiration not specified)
http://www.pnas.org/local/img/nav/footer-pnas.png (expiration not specified)
http://www.pnas.org/local/img/nav/glencoe_logo_small.png (expiration not specified)
http://www.pnas.org/local/img/nav/headline.png (expiration not specified)
http://www.pnas.org/local/img/nav/icon-highwire.png (expiration not specified)
http://www.pnas.org/local/img/nav/icon-nas.png (expiration not specified)
http://www.pnas.org/local/img/nav/nav-article-bg.png (expiration not specified)
http://www.pnas.org/local/img/nav/nav-divider2.png (expiration not specified)
http://www.pnas.org/local/js/expand.js (expiration not specified)
http://www.pnas.org/local/js/hw-local-global.js (expiration not specified)
http://www.pnas.org/local/js/hw-local-js-settings.js (expiration not specified)
http://www.pnas.org/local/js/jquery-1.7.2.min.js (expiration not specified)
http://www.pnas.org/local/js/jquery.tabify.js (expiration not specified)
http://www.pnas.org/local/js/jquery.ui.widget.min.js (expiration not specified)
http://www.pnas.org/local/js/modernizr.js (expiration not specified)
http://www.pnas.org/local/js/pages/pnas-home.js (expiration not specified)
http://www.pnas.org/local/js/script.js (expiration not specified)
http://www.pnas.org/shared/js/design/hw-design1.js (expiration not specified)
http://www.pnas.org/shared/js/fingerprint.js (expiration not specified)
http://www.pnas.org/shared/js/hw-shared.js (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_ArsTechnica.png (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_HuffingtonPost.png (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_NationalGeographic.png (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_ScientificAmerican.png (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_USNewsandWorld.png (expiration not specified)
http://www.pnas.org/site/misc/images/Icon_WashingtonPost.png (expiration not specified)
http://www.pnas.org/site/misc/images/Monroe.292.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/driving-home.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/mayBerenbaumPodcastImage-Homepage.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/mouse-home.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/sonifying-home.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/testtubes-home.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/video-games-home.jpg (expiration not specified)
http://www.pnas.org/site/misc/images/worlds-home.jpg (expiration not specified)
https://d1bxh8uas1mnw7.cloudfront.net/assets/embed.js (expiration not specified)
https://d1uo4w7k31k5mn.cloudfront.net/donut/0.png (expiration not specified)
http://www.pnas.org/content/114/18/local/cover-banner.jpg (2 minutes)
http://connect.facebook.net/en_US/all.js (20 minutes)
http://www.pnas.org/local/css/hw-local-global-overrides.css (60 minutes)
http://www.pnas.org/local/css/hw-local-global-pages.css (60 minutes)
http://www.pnas.org/local/css/hw-local-global.css (60 minutes)
http://www.pnas.org/local/css/hw-local-home.css (60 minutes)
http://www.pnas.org/local/css/hw-local-sidebar.css (60 minutes)
http://www.pnas.org/local/img/misc/arrow-green.gif (60 minutes)
http://www.pnas.org/local/img/misc/arrow-white.gif (60 minutes)
http://www.pnas.org/local/img/misc/btn-go.gif (60 minutes)
http://www.pnas.org/local/img/misc/rss.gif (60 minutes)
http://www.pnas.org/local/img/nav/btn-search.gif (60 minutes)
http://www.pnas.org/local/img/nav/pnas-header-logo.gif (60 minutes)
http://www.pnas.org/local/img/sidebar/square.gif (60 minutes)
http://www.pnas.org/shared/css/hw-global-citation.css (60 minutes)
http://www.pnas.org/shared/css/hw-global-classes.css (60 minutes)
http://www.pnas.org/shared/css/hw-global-dynamic-elements.css (60 minutes)
http://www.pnas.org/shared/css/hw-global-elements.css (60 minutes)
http://www.pnas.org/shared/css/hw-global-sidebars.css (60 minutes)
http://www.pnas.org/shared/css/hw-global.css (60 minutes)
http://www.pnas.org/shared/css/standard-designs/design25/d25-page-home.css (60 minutes)
http://www.pnas.org/shared/css/standard-designs/design25/d25-sidebar.css (60 minutes)
http://www.pnas.org/shared/css/standard-designs/design25/main.css (60 minutes)
http://www.pnas.org/shared/css/standard-designs/design25/ui.css (60 minutes)
http://www.pnas.org/site/css/global_styles.css (60 minutes)
http://www.pnas.org/site/css/main.css (60 minutes)
http://www.pnas.org/site/misc/images/includeimages/sessions-overlay-lg.gif (60 minutes)
http://www.google-analytics.com/ga.js (2 hours)

priority - 18Optimize images

Properly formatting and compressing images can save many bytes of data.

Optimize the following images to reduce their size by 173.6KiB (52% reduction).

Compressing http://www.pnas.org/content/114/18/local/cover-banner.jpg could save 47.3KiB (35% reduction).
Compressing http://www.pnas.org/site/misc/images/mayBerenbaumPodcastImage-Homepage.jpg could save 28.1KiB (73% reduction).
Compressing http://www.pnas.org/site/misc/images/sonifying-home.jpg could save 22.6KiB (91% reduction).
Compressing http://www.pnas.org/site/misc/images/video-games-home.jpg could save 19.6KiB (92% reduction).
Compressing http://www.pnas.org/site/misc/images/worlds-home.jpg could save 19.4KiB (91% reduction).
Compressing https://d1uo4w7k31k5mn.cloudfront.net/donut/0.png could save 10.5KiB (78% reduction).
Compressing http://www.pnas.org/site/misc/images/Icon_ArsTechnica.png could save 2.7KiB (63% reduction).
Compressing http://www.pnas.org/local/img/nav/headline.png could save 2.2KiB (33% reduction).
Compressing http://www.pnas.org/site/misc/images/Monroe.292.jpg could save 1.8KiB (20% reduction).
Compressing http://www.pnas.org/local/img/misc/btn-go.gif could save 1.6KiB (65% reduction).
Compressing http://www.pnas.org/local/img/nav/btn-search.gif could save 1.5KiB (67% reduction).
Compressing http://www.pnas.org/local/img/misc/arrow-green.gif could save 1.1KiB (84% reduction).
Compressing http://www.pnas.org/local/img/sidebar/square.gif could save 1.1KiB (93% reduction).
Compressing http://www.pnas.org/local/img/misc/arrow-white.gif could save 1.1KiB (87% reduction).
Compressing http://www.pnas.org/local/img/nav/icon-nas.png could save 1KiB (37% reduction).
Compressing http://www.pnas.org/site/misc/images/testtubes-home.jpg could save 1,012B (36% reduction).
Compressing http://www.pnas.org/site/misc/images/includeimages/sessions-overlay-lg.gif could save 1,003B (27% reduction).
Compressing http://www.pnas.org/local/img/nav/footer-pnas.png could save 998B (55% reduction).
Compressing http://www.pnas.org/site/misc/images/driving-home.jpg could save 983B (45% reduction).
Compressing http://www.pnas.org/site/misc/images/mouse-home.jpg could save 967B (46% reduction).
Compressing http://www.pnas.org/site/misc/images/Icon_WashingtonPost.png could save 890B (37% reduction).
Compressing http://www.pnas.org/local/img/nav/nav-divider2.png could save 870B (85% reduction).
Compressing http://www.pnas.org/local/img/nav/glencoe_logo_small.png could save 869B (29% reduction).
Compressing http://www.pnas.org/site/misc/images/Icon_NationalGeographic.png could save 849B (43% reduction).
Compressing http://www.pnas.org/local/img/nav/icon-highwire.png could save 842B (25% reduction).
Compressing https://scontent-atl3-1.xx.fbcdn.net/v/t1.0-0/p130…c33049d8d3&oe=598D2ADF could save 813B (12% reduction).
Compressing https://external-atl3-1.xx.fbcdn.net/safe_image.ph…_hash=AQAAcmhTqi2iaURA could save 798B (14% reduction).
Compressing http://www.pnas.org/site/misc/images/Icon_ScientificAmerican.png could save 700B (20% reduction).
Compressing http://www.pnas.org/site/misc/images/Icon_USNewsandWorld.png could save 579B (17% reduction).

priority - 10Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 14 blocking script resources and 22 blocking CSS resources. This causes a delay in rendering your page.

Remove render-blocking JavaScript:

http://www.pnas.org/local/js/jquery-1.7.2.min.js
http://www.pnas.org/local/js/jquery.ui.widget.min.js
http://www.pnas.org/local/js/modernizr.js
http://www.pnas.org/shared/js/fingerprint.js
http://www.pnas.org/shared/js/hw-shared.js
http://www.pnas.org/local/js/hw-local-js-settings.js
http://www.pnas.org/local/js/jquery.tabify.js
http://www.pnas.org/local/js/hw-local-global.js
http://www.pnas.org/local/js/expand.js
http://www.pnas.org/local/js/script.js
http://www.pnas.org/shared/js/design/hw-design1.js
http://pnas-movie.glencoesoftware.com/static/video_inline.min.js
http://www.pnas.org/local/js/pages/pnas-home.js
http://connect.facebook.net/en_US/all.js

Optimize CSS Delivery of the following:

http://www.pnas.org/shared/css/hw-global.css
http://www.pnas.org/shared/css/hw-global-sidebars.css
http://www.pnas.org/shared/css/hw-global-elements.css
http://www.pnas.org/shared/css/hw-global-citation.css
http://www.pnas.org/shared/css/hw-global-classes.css
http://www.pnas.org/shared/css/hw-global-dynamic-elements.css
http://www.pnas.org/shared/css/standard-designs/design25/main.css
http://www.pnas.org/shared/css/standard-designs/design25/ui.css
http://www.pnas.org/shared/css/standard-designs/design25/d25-page-home.css
http://www.pnas.org/shared/css/standard-designs/design25/d25-sidebar.css
http://www.pnas.org/local/css/hw-local-global.css
http://www.pnas.org/local/css/hw-local-global-overrides.css
http://www.pnas.org/local/css/hw-local-global-pages.css
http://fonts.googleapis.com/css?family=Open+Sans:400,700,600
http://fonts.googleapis.com/css?family=Open+Sans:4…alic,700italic,400,700
http://www.pnas.org/local/css/hw-local-sidebar.css
http://netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css
http://pnas-movie.glencoesoftware.com/static/video-js.min.css
http://www.pnas.org/shared/css/standard-designs/design25/d25-page-home.css
http://www.pnas.org/local/css/hw-local-home.css
http://www.pnas.org/site/css/main.css
http://www.pnas.org/site/css/global_styles.css

priority - 6Enable compression

Compressing resources with gzip or deflate can reduce the number of bytes sent over the network.

Enable compression for the following resources to reduce their transfer size by 58.5KiB (69% reduction).

Compressing https://d1bxh8uas1mnw7.cloudfront.net/assets/altme…c54ed2cf76e03255a18.js could save 58.5KiB (69% reduction).

priority - 1Minify CSS

Compacting CSS code can save many bytes of data and speed up download and parse times.

Minify CSS for the following resources to reduce their size by 7.9KiB (28% reduction).

Minifying http://www.pnas.org/local/css/hw-local-global.css could save 3.1KiB (29% reduction) after compression.
Minifying http://www.pnas.org/site/css/global_styles.css could save 1.2KiB (25% reduction) after compression.
Minifying http://www.pnas.org/shared/css/standard-designs/design25/ui.css could save 1.1KiB (26% reduction) after compression.
Minifying http://www.pnas.org/shared/css/hw-global-elements.css could save 1KiB (44% reduction) after compression.
Minifying http://www.pnas.org/shared/css/hw-global-citation.css could save 754B (38% reduction) after compression.
Minifying http://www.pnas.org/shared/css/hw-global-sidebars.css could save 754B (20% reduction) after compression.

priority - 1Minify JavaScript

Compacting JavaScript code can save many bytes of data and speed up downloading, parsing, and execution time.

Minify JavaScript for the following resources to reduce their size by 4.1KiB (30% reduction).

Minifying http://www.pnas.org/shared/js/hw-shared.js could save 2KiB (23% reduction) after compression.
Minifying http://www.pnas.org/local/js/expand.js could save 1.3KiB (45% reduction) after compression.
Minifying http://www.pnas.org/shared/js/fingerprint.js could save 754B (36% reduction) after compression.

priority - 0Reduce server response time

priority - 0Minify HTML

Compacting HTML code, including any inline JavaScript and CSS contained in it, can save many bytes of data and speed up download and parse times.

Minify HTML for the following resources to reduce their size by 1.6KiB (18% reduction).

Minifying http://www.pnas.org/ could save 1.6KiB (18% reduction) after compression.

pnas.org Desktop Resource Breakdown

Total Resources115
Number of Hosts16
Static Resources94
JavaScript Resources26
CSS Resources26

pnas.org mobile page speed rank

Last tested: 2019-12-04


Mobile Speed Bad
47/100

pnas.org Mobile Speed Test Quick Summary


priority - 64Eliminate render-blocking JavaScript and CSS in above-the-fold content

Your page has 10 blocking script resources and 10 blocking CSS resources. This causes a delay in rendering your page.

Remove render-blocking JavaScript:

https://www.pnas.org/sites/all/libraries/modernizr/modernizr.min.js?q1sev1
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js
https://pnas-movie.glencoesoftware.com/static/video_inline.min.js
https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js

Optimize CSS Delivery of the following:

https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://www.pnas.org/sites/all/modules/highwire/hi…le.highwire.css?q1sev1
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://pnas-movie.glencoesoftware.com/static/video-js.min.css
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://www.pnas.org/sites/default/files/advagg_cs…7FAp5jNUcqM9Qt4tH4.css
https://cdn.foxycart.com/pnas.ecommerce.highwire.o…_styles.1575448245.css

priority - 26Avoid landing page redirects

Your page has 2 redirects. Redirects introduce additional delays before the page can be loaded.

Avoid landing page redirects for the following chain of redirected URLs.

http://pnas.org/
http://www.pnas.org/
https://www.pnas.org/

priority - 24Enable compression

Compressing resources with gzip or deflate can reduce the number of bytes sent over the network.

Enable compression for the following resources to reduce their transfer size by 231.2KiB (76% reduction).

Compressing https://pnas-movie.glencoesoftware.com/static/video_inline.min.js could save 231.2KiB (76% reduction).

priority - 8Prioritize visible content

Your page requires additional network round trips to render the above-the-fold content. For best performance, reduce the amount of HTML needed to render above-the-fold content.

The entire HTML response was not sufficient to render the above-the-fold content. This usually indicates that additional resources, loaded after HTML parsing, were required to render above-the-fold content. Prioritize visible content that is needed for rendering above-the-fold by including it directly in the HTML response.

Only about 15% of the final above-the-fold content could be rendered with the full HTML response.
Click to see the screenshot with only the HTML response:

priority - 4Leverage browser caching

Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.

Leverage browser caching for the following cacheable resources:

https://pnas-movie.glencoesoftware.com/static/video-js.min.css (expiration not specified)
https://pnas-movie.glencoesoftware.com/static/video_inline.min.js (expiration not specified)
https://cdn.foxycart.com/pnas.ecommerce.highwire.org/loader.js (90 seconds)
https://pnascomments.disqus.com/count.js?_=1575482059371 (5 minutes)
https://www.google-analytics.com/analytics.js (2 hours)

priority - 1Reduce server response time

In our test, your server responded in 0.24 seconds.

priority - 0Minify CSS

Compacting CSS code can save many bytes of data and speed up download and parse times.

Minify CSS for the following resources to reduce their size by 607B (32% reduction).

Minifying https://www.pnas.org/sites/all/modules/highwire/hi…le.highwire.css?q1sev1 could save 607B (32% reduction) after compression.

priority - 0Minify JavaScript

Compacting JavaScript code can save many bytes of data and speed up downloading, parsing, and execution time.

Minify JavaScript for the following resources to reduce their size by 146B (15% reduction).

Minifying https://www.pnas.org/sites/default/files/advagg_js…Q7FAp5jNUcqM9Qt4tH4.js could save 146B (15% reduction) after compression.

pnas.org Mobile Resource Breakdown

Total Resources60
Number of Hosts9
Static Resources48
JavaScript Resources17
CSS Resources10

pnas.org mobile page usability

Last tested: 2019-12-04


Mobile Usability Good
96/100

pnas.org Mobile Usability Test Quick Summary


priority - 3Size content to viewport

The page content is too wide for the viewport, forcing the user to scroll horizontally. Size the page content to the viewport to provide a better user experience.

The page content is 456 CSS pixels wide, but the viewport is only 412 CSS pixels wide. The following elements fall outside the viewport:

The element <div class="region region-…col-mobile-24">Main menuUser…dvanced search</div> falls outside the viewport.
The element <span class="element-invisible">published ahea…print articles</span> falls outside the viewport.

priority - 0Size tap targets appropriately

Some of the links/buttons on your webpage may be too small for a user to easily tap on a touchscreen. Consider making these tap targets larger to provide a better user experience.

The following tap targets are close to other nearby tap targets and may need additional spacing around them.

The tap target <a href="#main-content" class="element-invisi…ment-focusable">Skip to main content</a> is close to 2 other tap targets.

The tap target <li class="trigger-0">Main menu</li> and 2 others are close to other tap targets.

The tap target <li class="trigger-1">User menu</li> and 1 others are close to other tap targets.

The tap target <a href="https://www.pn…content/116/49">Volume 116, Is…issue of PNAS.</a> is close to 1 other tap targets.

The tap target <button type="button" class="agree-button e…default-button">Continue</button> is close to 1 other tap targets.

The tap target <button type="button" class="find-more-butt…tton-processed">Find out more</button> is close to 1 other tap targets.

pnas.org HTML validation

Errors

Attribute “xmlns:mml” not allowed here.

Line: 4 Column: 16 - 49
"...TYPE html> <html lang="en" dir="ltr" xmlns="http://www.w3.org/1999/xhtml" xmlns:mml="http://www.w3.org/1998/Math/MathML"> <he..."

The “profile” attribute on the “head” element is obsolete. To declare which “meta” terms are used in the document, instead register the names as meta extensions. To trigger specific UA behaviors, use a “link” element instead.

Line: 5 Column: 50 - 53
"...h/MathML"> <head profile="http://www.w3.org/1999/xhtml/vocab"> <..."

Duplicate ID “logo”.

Line: 338 Column: 17 - 51
"... <a href="/" title="Home" id="logo"> ..."

Element “source” is missing required attribute “srcset”.

Line: 632 Column: 1 - 489
"...endif]--> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_1_5x/public/coverbanner.jpg?itok=evCbRCPS&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide/public/coverbanner.jpg?itok=5CBtJvOv&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_2x/public/coverbanner.jpg?itok=TBYJJ5ho&amp;timestamp=1550612805 2x" media="all and (min-width: 1220px)" /> <sour..." Line: 633 Column: 1 - 612
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/coverbanner.jpg?itok=LaJkllac&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/coverbanner.jpg?itok=K7k8A6lt&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/coverbanner.jpg?itok=_tvYYg_x&amp;timestamp=1550612805 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 634 Column: 1 - 602
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/coverbanner.jpg?itok=NgTbVRK5&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/coverbanner.jpg?itok=5SfgzFjL&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/coverbanner.jpg?itok=8dbcJzCZ&amp;timestamp=1550612805 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 635 Column: 1 - 497
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_1_5x/public/coverbanner.jpg?itok=T8qa9u1P&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2/public/coverbanner.jpg?itok=5EHZMk0y&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_2x/public/coverbanner.jpg?itok=ZBfwAZNV&amp;timestamp=1550612805 2x" media="all and (min-width: 380px)" /> <sour..." Line: 636 Column: 1 - 492
"...80px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/coverbanner.jpg?itok=NgTbVRK5&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/coverbanner.jpg?itok=5SfgzFjL&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/coverbanner.jpg?itok=8dbcJzCZ&amp;timestamp=1550612805 2x" media="all and (min-width: 0px)" /> <!--[..." Line: 665 Column: 1 - 495
"...endif]--> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_1_5x/public/PNAS-Carousel.png?itok=eXX2_lEU&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide/public/PNAS-Carousel.png?itok=M4O6vxqt&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_2x/public/PNAS-Carousel.png?itok=9wvTrm_T&amp;timestamp=1532526780 2x" media="all and (min-width: 1220px)" /> <sour..." Line: 666 Column: 1 - 618
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/PNAS-Carousel.png?itok=6xWEgMX7&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/PNAS-Carousel.png?itok=5ssUAEAQ&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/PNAS-Carousel.png?itok=8dMsofld&amp;timestamp=1532526780 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 667 Column: 1 - 608
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/PNAS-Carousel.png?itok=mEB_Xq_T&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/PNAS-Carousel.png?itok=e5xvLYXU&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/PNAS-Carousel.png?itok=hLgKpgoJ&amp;timestamp=1532526780 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 668 Column: 1 - 503
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_1_5x/public/PNAS-Carousel.png?itok=gJJi8ygO&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2/public/PNAS-Carousel.png?itok=qD9xLFNp&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_2x/public/PNAS-Carousel.png?itok=fvSVeuxl&amp;timestamp=1532526780 2x" media="all and (min-width: 380px)" /> <sour..." Line: 669 Column: 1 - 498
"...80px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/PNAS-Carousel.png?itok=mEB_Xq_T&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/PNAS-Carousel.png?itok=e5xvLYXU&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/PNAS-Carousel.png?itok=hLgKpgoJ&amp;timestamp=1532526780 2x" media="all and (min-width: 0px)" /> <!--[..." Line: 698 Column: 1 - 474
"...endif]--> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_1_5x/public/021919.jpg?itok=OtxZz4q2&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide/public/021919.jpg?itok=5IhgK00Q&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_2x/public/021919.jpg?itok=kAi3-j1n&amp;timestamp=1550612363 2x" media="all and (min-width: 1220px)" /> <sour..." Line: 699 Column: 1 - 597
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/021919.jpg?itok=mtP-ogr7&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/021919.jpg?itok=CWlwqTZi&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/021919.jpg?itok=gVBLKR3u&amp;timestamp=1550612363 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 700 Column: 1 - 587
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/021919.jpg?itok=r7NLOExL&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/021919.jpg?itok=F3NBV3Nv&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/021919.jpg?itok=KooRRE5u&amp;timestamp=1550612363 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 701 Column: 1 - 482
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_1_5x/public/021919.jpg?itok=fPnMB7WT&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2/public/021919.jpg?itok=ecSB0Twm&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_2x/public/021919.jpg?itok=Rd-yJoWf&amp;timestamp=1550612363 2x" media="all and (min-width: 380px)" /> <sour..." Line: 702 Column: 1 - 477
"...80px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/021919.jpg?itok=r7NLOExL&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/021919.jpg?itok=F3NBV3Nv&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/021919.jpg?itok=KooRRE5u&amp;timestamp=1550612363 2x" media="all and (min-width: 0px)" /> <!--[..." Line: 731 Column: 1 - 540
"...endif]--> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_1_5x/public/20190218_carousel_ad_belarus.png?itok=Z0aEr4He&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide/public/20190218_carousel_ad_belarus.png?itok=isN1OMoB&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_wide_2x/public/20190218_carousel_ad_belarus.png?itok=wb09xSug&amp;timestamp=1550612470 2x" media="all and (min-width: 1220px)" /> <sour..." Line: 732 Column: 1 - 663
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/20190218_carousel_ad_belarus.png?itok=vZCfzdoZ&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/20190218_carousel_ad_belarus.png?itok=dMcmjFoo&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/20190218_carousel_ad_belarus.png?itok=Bx1jGB2m&amp;timestamp=1550612470 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 733 Column: 1 - 653
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/20190218_carousel_ad_belarus.png?itok=65d_y3lm&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/20190218_carousel_ad_belarus.png?itok=t68nY-0u&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/20190218_carousel_ad_belarus.png?itok=02pOk2cb&amp;timestamp=1550612470 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 734 Column: 1 - 548
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_1_5x/public/20190218_carousel_ad_belarus.png?itok=db1FOCHf&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2/public/20190218_carousel_ad_belarus.png?itok=capJFiQE&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_mobile2_2x/public/20190218_carousel_ad_belarus.png?itok=ONAMGgPO&amp;timestamp=1550612470 2x" media="all and (min-width: 380px)" /> <sour..." Line: 735 Column: 1 - 543
"...80px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/20190218_carousel_ad_belarus.png?itok=65d_y3lm&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/20190218_carousel_ad_belarus.png?itok=t68nY-0u&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/20190218_carousel_ad_belarus.png?itok=02pOk2cb&amp;timestamp=1550612470 2x" media="all and (min-width: 0px)" /> <!--[..."

Bad value “all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)” for attribute “media” on element “source”: Deprecated media feature “min-device-width”. For guidance, see the Deprecated Media Features section in the current Media Queries specification.

Line: 633 Column: 1 - 612
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/coverbanner.jpg?itok=LaJkllac&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/coverbanner.jpg?itok=K7k8A6lt&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/coverbanner.jpg?itok=_tvYYg_x&amp;timestamp=1550612805 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 666 Column: 1 - 618
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/PNAS-Carousel.png?itok=6xWEgMX7&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/PNAS-Carousel.png?itok=5ssUAEAQ&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/PNAS-Carousel.png?itok=8dMsofld&amp;timestamp=1532526780 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 699 Column: 1 - 597
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/021919.jpg?itok=mtP-ogr7&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/021919.jpg?itok=CWlwqTZi&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/021919.jpg?itok=gVBLKR3u&amp;timestamp=1550612363 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..." Line: 732 Column: 1 - 663
"...20px)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_1_5x/public/20190218_carousel_ad_belarus.png?itok=vZCfzdoZ&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal/public/20190218_carousel_ad_belarus.png?itok=dMcmjFoo&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_normal_2x/public/20190218_carousel_ad_belarus.png?itok=Bx1jGB2m&amp;timestamp=1550612470 2x" media="all and (min-width: 980px) and (min-device-width: 980px), all and (max-device-width: 1024px) and (min-width: 1024px) and (orientation:landscape)" /> <sour..."

Bad value “all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)” for attribute “media” on element “source”: Deprecated media feature “min-device-width”. For guidance, see the Deprecated Media Features section in the current Media Queries specification.

Line: 634 Column: 1 - 602
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/coverbanner.jpg?itok=NgTbVRK5&amp;timestamp=1550612805 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/coverbanner.jpg?itok=5SfgzFjL&amp;timestamp=1550612805 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/coverbanner.jpg?itok=8dbcJzCZ&amp;timestamp=1550612805 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 667 Column: 1 - 608
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/PNAS-Carousel.png?itok=mEB_Xq_T&amp;timestamp=1532526780 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/PNAS-Carousel.png?itok=e5xvLYXU&amp;timestamp=1532526780 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/PNAS-Carousel.png?itok=hLgKpgoJ&amp;timestamp=1532526780 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 700 Column: 1 - 587
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/021919.jpg?itok=r7NLOExL&amp;timestamp=1550612363 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/021919.jpg?itok=F3NBV3Nv&amp;timestamp=1550612363 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/021919.jpg?itok=KooRRE5u&amp;timestamp=1550612363 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..." Line: 733 Column: 1 - 653
"...cape)" /> <source data-srcset="https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_1_5x/public/20190218_carousel_ad_belarus.png?itok=65d_y3lm&amp;timestamp=1550612470 1.5x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow/public/20190218_carousel_ad_belarus.png?itok=t68nY-0u&amp;timestamp=1550612470 1x, https://www.pnas.org/sites/default/files/styles/hwfeat_slide_img_col_narrow_2x/public/20190218_carousel_ad_belarus.png?itok=02pOk2cb&amp;timestamp=1550612470 2x" media="all and (min-width: 768px) and (min-device-width: 768px), (max-device-width: 800px) and (min-width: 768px) and (orientation:landscape)" /> <sour..."

Bad value “auto” for attribute “height” on element “img”: Expected a digit but saw “a” instead.

Line: 1397 Column: 91 - 218
"...title="0"><img class="footer-logo" src="https://www.pnas.org/sites/default/files/pnas_2x.png" width="200" height="auto" alt="Site Logo" /></a> ..."

Warnings

Attribute with the local name “xmlns:mml” is not serializable as XML 1.0.

Line: 4 Column: 16 - 49
"...TYPE html> <html lang="en" dir="ltr" xmlns="http://www.w3.org/1999/xhtml" xmlns:mml="http://www.w3.org/1998/Math/MathML"> <he..."

The “type” attribute for the “style” element is not needed and should be omitted.

Line: 20 Column: 1 - 35
"...="all" /> <style type="text/css" media="all"> /* <!..." Line: 28 Column: 1 - 35
"...="all" /> <style type="text/css" media="all"> /* <!..."

The “type” attribute is unnecessary for JavaScript resources.

Line: 34 Column: 5 - 35
"...l" /> <script type="text/javascript"> <!--/..." Line: 44 Column: 1 - 112
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/all/libraries/modernizr/modernizr.min.js?pnfdkp"></scri..." Line: 45 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 50 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__jGfr-z48ZirLL12EDvReR-YRbZ4N6vPtvjD3lseF4Qk__jRmaEG3bS-J0h9OK87VG9-RsRYkQMxzGb6KkmTsutpM__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 51 Column: 1 - 243
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__3LuYkqUjZCBoSLlHr2m61kSbmsCSqUKFXy8HcWtx3W4__fjMmdyFoQfs65a7ohq9q0rrTzQSedREzEOJ7PEgkNE8__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js" async="async"></scri..." Line: 52 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__2ibhIidgCCLy8iz70loEqt4qxHMTCOA_4G9_TUTA92Y__MPpdV7ssa7b9kuwzdKP7C39jE6tsbpfSlX8Ei4xarZk__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 53 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 58 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__3vwOA0BwlnyBkt9H4CLg6FgNyKAh--OmfOxFOIu_5S4__EXTgktcHbQ7BQfelY6CnrqgPRc4i4eD6XcZ4i3xs5RU__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 59 Column: 1 - 122
"...</script> <script type="text/javascript" defer="defer" async="async" src="//cdn.foxycart.com/pnas.ecommerce.highwire.org/loader.js"></scri..." Line: 60 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__V5Z2KQjolV4PfM1QPTJBfgFALtlxrpRlGUlfwjUzRCc__P7kd4NRkC7zOucwBlYKniJRrvFz_Wud1FwmuHJHTUq4__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 61 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 66 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__JsxqoHyPiHRT4Ty1fTQXmXXWy2w2qgWE2k86zsLAoEs__cjP1ZlaiXPzo7e6S5C40znP-dJ8CMA49tto0qnyJCRg__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 67 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 1548 Column: 5 - 233
"... --> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__bnwyEQSuZLC-kZnFqCi5iE02nOCzM7DjY7zYxcN9nsQ__VBiBT_qq_eHMMO2Q1rXK1u-hHff31XLUkmi9dgjuPeY__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 1549 Column: 1 - 243
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__GM3GJPR36rRIz0TRkjC5OQwrioSyN9aoYRivDhCO_AM__qAl84FcCv2jyN22yFGS5Oc85cjd9zKX6p_cFNLGhe-M__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js" async="async"></scri..." Line: 1550 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__zTI_-Htm-XX3S8-Y9eYmNlLVTFY2LbpnQUfg3DskMq8__ufeH_iMPS2cZiqUipEu8Tats9yOufpbRgl0YLP_oZFg__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..." Line: 1551 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 1556 Column: 1 - 31
"...</script> <script type="text/javascript"> <!--/..." Line: 1561 Column: 1 - 97
"...</script> <script type="text/javascript" src="//pnas-movie.glencoesoftware.com/static/video_inline.min.js"></scri..." Line: 1562 Column: 1 - 229
"...</script> <script type="text/javascript" src="https://www.pnas.org/sites/default/files/advagg_js/js__bOP4a_cSySEQ3bHcuBja85t09rGJf3PnPsYzce52Y5Q__-_HseC4_Tnobyghi__HhYlyZP2jcAZlmZo4zGAAlL3g__eD-fMBbK3rzkqX-DKnaPiSMfZk-HlPfEyvhsC6r-EbA.js"></scri..."

The “banner” role is unnecessary for element “header”.

Line: 82 Column: 3 - 75
"..."page"> <header role="banner" class="section section-header" id="section-header"> ..."

The first occurrence of ID “logo” was here.

Line: 319 Column: 5 - 106
"...ent"> <a href="/" rel="home" id="logo" title="Home" class="" data-icon-position="" data-hide-link-title="0"><img s..."

Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.

Line: 625 Column: 3 - 69
"...e-row"> <article class="node-view-teaser node-hwfeat-image-slideshow-item"> <d..." Line: 658 Column: 3 - 69
"...e-row"> <article class="node-view-teaser node-hwfeat-image-slideshow-item"> <d..." Line: 691 Column: 3 - 69
"...e-row"> <article class="node-view-teaser node-hwfeat-image-slideshow-item"> <d..." Line: 724 Column: 3 - 69
"...e-row"> <article class="node-view-teaser node-hwfeat-image-slideshow-item"> <d..." Line: 805 Column: 5 - 57
"...rst"> <article class="node-view-teaser node-featured-item"> ..." Line: 827 Column: 5 - 57
"...ven"> <article class="node-view-teaser node-featured-item"> ..." Line: 849 Column: 5 - 57
"...ast"> <article class="node-view-teaser node-featured-item"> ..." Line: 893 Column: 5 - 57
"...rst"> <article class="node-view-teaser node-featured-item"> ..." Line: 915 Column: 5 - 57
"...ven"> <article class="node-view-teaser node-featured-item"> ..." Line: 937 Column: 5 - 57
"...ast"> <article class="node-view-teaser node-featured-item"> ..." Line: 1070 Column: 5 - 57
"...ast"> <article class="node-view-teaser node-featured-item"> ..." Line: 1132 Column: 5 - 57
"...ast"> <article class="node-view-teaser node-featured-item"> ..."

The “contentinfo” role is unnecessary for element “footer”.

Line: 1370 Column: 3 - 80
"...nt --> <footer role="contentinfo" class="section section-footer" id="section-footer"> ..."

pnas.org similar domains

Similar domains:
www.pnas.com
www.pnas.net
www.pnas.org
www.pnas.info
www.pnas.biz
www.pnas.us
www.pnas.mobi
www.nas.org
www.pnas.org
www.onas.org
www.ponas.org
www.opnas.org
www.lnas.org
www.plnas.org
www.lpnas.org
www.pas.org
www.pbas.org
www.pnbas.org
www.pbnas.org
www.phas.org
www.pnhas.org
www.phnas.org
www.pjas.org
www.pnjas.org
www.pjnas.org
www.pmas.org
www.pnmas.org
www.pmnas.org
www.pns.org
www.pnqs.org
www.pnaqs.org
www.pnqas.org
www.pnws.org
www.pnaws.org
www.pnwas.org
www.pnss.org
www.pnass.org
www.pnsas.org
www.pnzs.org
www.pnazs.org
www.pnzas.org
www.pna.org
www.pnaw.org
www.pnasw.org
www.pnae.org
www.pnase.org
www.pnaes.org
www.pnad.org
www.pnasd.org
www.pnads.org
www.pnaz.org
www.pnasz.org
www.pnax.org
www.pnasx.org
www.pnaxs.org
www.pnaa.org
www.pnasa.org
www.pnaas.org

pnas.org Ping

Ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol (IP) network. It measures the round-trip time for messages sent from the originating host to a destination computer that are echoed back to the source.


pnas.org TRACEROUTE

Traceroute is a computer network diagnostic tool for displaying the route (path) and measuring transit delays of packets across an Internet Protocol (IP) network. The history of the route is recorded as the round-trip times of the packets received from each successive host (remote node) in the route (path); the sum of the mean times in each hop is a measure of the total time spent to establish the connection. Traceroute proceeds unless all (three) sent packets are lost more than twice, then the connection is lost and the route cannot be evaluated.