How PhD assessment needs to change

What matters in science | 

View this email in your browser Friday 22 March 2024

Hello Nature readers, Today we discover why like-charged particles in liquids sometimes attract, hear how an X-factor in male birds' song makes them irresistible to females and hear what Briefing readers think about how PhD assessment needs to change.

The system, developed by a team led by Google scientists, is called Health Acoustic Representations (HeAR) (Getty)

The tell-tale cough A machine-learning tool shows promise for detecting COVID-19 and tuberculosis from a person's cough. While previous tools used medically annotated data, this model was trained on more than 300 million clips of coughing, breathing and throat clearing from YouTube videos. Although it's too early to tell whether this will become a commercial product, "there's an immense potential not only for diagnosis, but also for screening" and monitoring, says laryngologist Yael Bensoussan. Nature | 5 min read Reference: arXiv preprint (not peer reviewed)

When like-charged particles attract Everyone knows that usually, when it comes to charged particles, opposites attract. But in liquids, birds of a feather can flock together. Researchers investigating the long-standing mystery of why like-charged particles in solution can be drawn to each other have found that the nature of the solvent is key. The way that the liquid molecules arrange themselves around the particles can generate enough 'electrosolvation force' to overcome electromagnetic repulsion. The findings might require "a major re-calibration of basic principles that we believe govern the interaction of molecules and particles, and that we encounter at an early stage in our schooling," says physical chemist and co-author Madhavi Krishnan. Physics World | 6 min read Reference: Nature Nanotechnology paper

Social media changes; debates don't A study of 34 years of online discussions from Usenet to YouTube shows that, when it comes to rude behaviour, people — not platforms — are the root of incivility. Researchers used Google's artificial-intelligence (AI) 'toxicity classifier' to identify "rude, disrespectful or unreasonable" comments. They found that over three decades, longer discussions tend to be more toxic, but heated debates don't necessarily escalate or drive away participants. "Despite changes in social media and social norms over time, certain human behaviours persist, including toxicity," says data scientist and co-author Walter Quattrociocchi. El País | 3 min read Reference: Nature paper

Reader poll

Last week, a Nature editorial argued that the way PhDs are assessed needs to change. Briefing readers largely agree. "I acknowledge granting a PhD is a messy business — there is no fixed bar that candidates have to meet to successfully defend," says recently minted physics PhD Kai Shinbrough. He says that more transparency around the process would go a long way to alleviate candidates' anxieties. Readers' suggestions included assessing dissertations in a similar way to grant proposals — in writing, with iterative feedback cycles — or opening theses to public comments. Many felt there should be more emphasis on evaluating PhD projects on their originality, methods and analysis rather than their 'positive' or 'negative' outcomes. Others highlighted that assessment shouldn't be generalized across all academic disciplines with their varying contexts, cultures and histories. "Breathless demands for sweeping innovation in yet another domain of higher education would certainly lead to additional demands on the time and workloads of supervisors" and further disincentivize PhD supervision, says linguist Mark Post. Several readers felt that their supervisors' hands-off leadership left them to mostly fend for themselves and missing out on learning important skills, such as grant writing or lab management. "Research should not be a painful or solitary endeavour, it should be a communal effort driven by individuals committed to serving society," says linguist Izadora Silva Pimenta.

Features & opinion

The largest mouse-embryo atlas A massive mouse-embryo map tracks the development of more than 12 million cells as they mature into organs and other tissues. Building these cell atlases typically requires multinational collaborations and lots of cash. But this one was completed in one year by a three-researcher team on a US$370,000 budget. Among the first insights from the data is that the transcriptome (the cells' set of messenger RNA) changes most dramatically in the hour just after birth: it's "the most stressful moment in your life", says geneticist and atlas co-creator Jay Shendure. Nature | 6 min read Reference: Nature paper

ACCESS NATURE AND 54 OTHER NATURE JOURNALS Nature+ is our most affordable 30-day subscription, giving you online access to a wide range of specialist Nature Portfolio journals, including Nature. Nature+ is for personal use and is suitable for students. Learn more about Nature+ in the Americas, in the UK and internationally.

Futures: The warfighter A casualty of faster-than-light travel and a teenage remnant of Homo sapiens grapple over whether it was all worth it in the latest short story for Nature's Futures series. Nature | 6 min read

Podcast: the bird song X factor Song differences too subtle for people to hear are the special spice that make some male zebra finches (Taeniopygia guttata) particularly attractive to females. Researchers used an AI algorithm to analyze various acoustic features and create maps of the songs' syllables. Female finches preferred songs with wider statistical gaps on these maps — they seem to be harder to learn and therefore indicate the singer's fitness. How this statistical distance translates into sonic quality isn't clear yet. "They all sounded like just a regular learned zebra finch on to our ear," says neuroscientist and study co-author Todd Roberts. Nature Podcast | 30 min listen Subscribe to the Nature Podcast on Apple Podcasts, Google Podcasts or Spotify, or use the RSS feed.

Share your snaps (Bing Lin) Nature's Working Scientist photo competition Primate-behaviour researcher Bing Lin took this photograph of a troop of gelada monkeys (Theropithecus gelada) making their way across Ethiopian highlands under a gathering storm in 2017. It was just one moment of many Lin captured during a year of studying the monkeys whilst living in a tent nearby. It was also the moment that won Nature's 2022 Working Scientist photo competition. Now, the competition returns. You could see your photo of scientists taking part in their craft — in or out of the lab — published in Nature, plus win a cash prize and a year's subscription. Find out more information here.

Quote of the day "Some people hide behind jargon because they don't necessarily feel comfortable trying to explain it." Biophysicist Esther Osarfo-Mensah says that using AI to help produce summaries of papers might help disseminate research to non-specialists. (Nature Index | 7 min read)

Today in our penguin-search puzzle, Leif Penguinson is enjoying the river landscape of Oulanka National Park in Finland. Can you find the penguin? The answer will be in Monday's e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton. This newsletter is always evolving — tell us what you think! Please send your feedback to briefing@nature.com. Flora Graham, senior editor, Nature Briefing With contributions by Katrina Krämer and Sarah Tomlin

Want more? Update your preferences to sign up to our other free Nature Briefing newsletters: Nature Briefing: Anthropocene — climate change, biodiversity, sustainability and geoengineering Nature Briefing: AI & Robotics — 100% written by humans, of course Nature Briefing: Cancer — a weekly newsletter written with cancer researchers in mind Nature Briefing: Translational Research covers biotechnology, drug discovery and pharma Please visit your preferences page to choose which Nature Briefing newsletters to receive (or to unsubscribe).

Join our community

You received this newsletter because you subscribed with the email address: manojdole1.Lens@blogger.com Please add briefing@nature.com to your address book. Enjoying this newsletter? You can use this form to recommend it to a friend or colleague — thank you! Had enough? To unsubscribe from this Briefing, but keep receiving your other Nature Briefing newsletters, please update your subscription preferences. To stop all Nature Briefing emails forever, click here to remove your personal data from our system. Fancy a bit of a read? View our privacy policy. Forwarded by a friend? Get the Briefing straight to your inbox: subscribe for free. Want to master time management, protect your mental health and brush up on your skills? Sign up for our free short e-mail series for working scientists, Back to the lab. Get more from Nature: Register for free on nature.com to sign up for other newsletters specific to your field and email alerts from Nature Research journals. Would you like to read the Briefing in other languages? Sign up for the weekly round-up e-mail in Arabic, curated and translated by the editors of Nature Arabic Edition. هل تود أن تقرأ هذا الموجز باللغة العربية؟ سَجِّل الآن لتصلك نشرة العلوم الموجزة أسبوعيًّا، التي يختار محتواها ويترجمه فريق محرري "نيتشر الطبعة العربية". Follow Nature Portfolio on WeChat for a weekly round-up post in Chinese, curated and translated by our team in China. 关注Nature Portfolio官方微信订阅号，每周二为您推送Nature Briefing精选中文内容——自然每周简报。 Nature | The Springer Nature Campus, 4 Crinan Street, London, N1 9XW, United Kingdom Nature Research, part of Springer Nature. © 2024 Springer Nature Limited. All rights reserved.