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Tracing cell trajectories in a biofilm

Science

Born in 1881 on a farm in Pennsylvania, Alice C. Evans dedicated her life to studying bacteria in dairy products. Early in her career, Alice became convinced that most bacteria display multicellular behavior as part of their life cycles. At the time, the morphological changes observed in bacterial life cycles created confusion among scientists. In 1928, as the first female president of the American Society for Microbiology, Alice wrote to the scientific community: “When one-celled organisms grow in masses, … individual cells influence and protect one another.” She continued, “Bacteriologists need not feel chagrinned … to admit that… forms they have considered as different genera are but stages in the life cycle of one species” ([ 1 ][1]). Nearly 100 years later, on page 71 of this issue, Qin et al. ([ 2 ][2]) make a substantial leap forward in deciphering cell dynamics in biofilms—groups of microorganisms that adhere to a surface, and each other, by excreting matrix components. In the interim period, microbiologists have learned that many bacteria organize in groups. This allows bacterial cells to achieve collectively what individuals in isolation cannot, thus conferring a selective advantage on the individuals. Multicellular behaviors help cells to migrate ([ 3 ][3]), resist antibiotic treatments ([ 4 ][4]), and protect themselves from predators ([ 5 ][5]). In recent years, microbiologists have begun to unravel the mechanisms behind these multicellular behaviors, by studying single-cell gene expression, growth rate regulation, and cell-to-cell interactions ([ 6 ][6]–[ 9 ][7]), as well as by developing tools to investigate the morphology and growth of entire bacterial biofilms ([ 10 ][8], [ 11 ][9]). A multicellular aggregate starts with a single founder cell that grows into a mature biofilm. Despite substantial progress, scientists still lack a detailed understanding of how bacterial cells are programmed to build multicellular structures. Each cell makes individual decisions—whether to divide, move, excrete chemicals, exert forces, or express extracellular matrix components—in response to its local environment. In turn, the local environment is determined by the collective decisions of all of its cells, played out as a mosaic over time in a three-dimensional (3D) space. A primary challenge to unraveling the mystery of how cells are programmed to produce a mature functional biofilm is that researchers lack the experimental tools needed to study how the dynamics of individual cells drive biofilm formation and structure. ![Figure][10] The building of biofilms A fountain-like flow of bacterial cells drives biofilm expansion. CREDIT: V. ALTOUNIAN/ SCIENCE In their elegant study, Qin et al. developed dual-view light-sheet microscopy to reconstruct single-cell trajectories in 3D Vibrio cholerae biofilms initiated by a single founder cell. This method fluorescently labeled cellular puncta, giving isotropic single-cell resolution in the biofilm with much less photobleaching than that seen with previous methods. This advance allowed the authors to carry out simultaneous imaging of 10,000 V. cholerae cells for the 16 hours it takes for the biofilm to develop, with 3-min intervals between subsequent images. This frequent imaging made it possible to track the trajectories of micrometer-sized cells, giving an unprecedented view into the behaviors of individual cells as the biofilm developed (see the figure). The measurements revealed a qualitative transition in an individual cell's behavior, in which Brownian motion changes to ballistic motion as the biofilm develops. This transition corresponds to a new phase of collective growth, when the biofilm as a whole begins its vertical expansion away from the substrate. In this phase, cells displayed two types of trajectories. Some of the cells expanded ballistically outward, whereas others became trapped at the substrate. Overall, these trajectories gave rise to a collective fountain-like flow, which transported some cells to the biofilm front, while bypassing the cells trapped at the substrate. This fountain-like flow allowed for fast lateral expansion of the biofilm. Cell tracking allowed Qin et al. to precisely quantify the dynamics of various cells, while also assessing how these dynamics differ for mutant cells that overproduce matrix components. To interpret the results, the authors built a mathematical model for the mechanics of biofilm expansion, balancing growth with substrate friction. By modeling different surface frictions and comparing the predicted cell motion with the observed cell motion, Qin et al. were able to explain the observed behavior as long as friction between the cells and surface was a dominant effect. This study of V. cholerae offers an exciting insight into how collective behavior can arise from processes operating at the single-cell level. The mechanisms uncovered with a gram-negative bacterial species likely will be generalizable across other bacterial types. For example, the qualitative transitions in biofilm expansion observed in this study have analogs in other bacterial biofilms. With the gram-positive bacterium Bacillus subtilis , a qualitative change in colony expansion is triggered by a cellular bistable switch in which cells expressing flagella produce extracellular matrices ([ 12 ][11], [ 13 ][12]). Osmolarity associated with matrix production drives colony expansion ([ 14 ][13]). More broadly, this study demonstrates the great potential for advances in imaging technology and computer vision to help unravel how collective behavior arises from the activity of individual cells and their interactions. However, there is much more going on inside a biofilm that cannot yet be seen. More complete information would allow researchers to not only reconstruct the motion of cells but also uncover their phenotypic states. Previous work on B. subtilis with fluorescent labeling of genetic components shows detailed spatial arrangement of various cell types, with cells carrying out different biological functions in distinct parts of the biofilm ([ 3 ][3], [ 15 ][14]). One can only hypothesize about the diversity of cellular types and functions inside the beautiful fountain revealed in the present study. A deeper understanding of bacterial multicellular behavior will increase our ability to treat bacterial infections, control natural bacterial communities, and engineer synthetic ones for specific purposes. 1. [↵][15]1. A. C. Evans , J. Bacteriol. 17, 63 (1929). [OpenUrl][16][FREE Full Text][17] 2. [↵][18]1. B. Qin et al ., Science 369, 71 (2020). [OpenUrl][19][Abstract/FREE Full Text][20] 3. [↵][21]1. J. van Gestel et al ., PLOS Biol. 13, e1002141 (2015). [OpenUrl][22][CrossRef][23][PubMed][24] 4. [↵][25]1. C. W. Hall, 2. T.-F. Mah , FEMS Microbiol. Rev. 41, 276 (2017). [OpenUrl][26][CrossRef][27] 5. [↵][28]1. P. K. Raghupathi et al ., Front. Microbiol. 8, 2649 (2018). [OpenUrl][29] 6. [↵][30]1. A. Dal Co, 2. S. van Vliet, 3. M. Ackermann , Philos. Trans. R. Soc. London Ser. B 374, 20190080 (2019). [OpenUrl][31] 7. 1. A. Dal Co et al ., Nat. Ecol. Evol. 4, 366 (2020). [OpenUrl][32] 8. 1. S. van Vliet et al ., Cell Syst. 6, 496 (2018). [OpenUrl][33] 9. [↵][34]1. A. Dragoš et al ., Curr. Biol. 28, 1903 (2018). [OpenUrl][35][CrossRef][36] 10. [↵][37]1. K. Drescher et al ., Proc. Natl. Acad. Sci. U.S.A. 113, E2066 (2016). [OpenUrl][38][Abstract/FREE Full Text][39] 11. [↵][40]1. R. Hartmann et al ., Nat. Phys. 15, 251 (2019). [OpenUrl][41][CrossRef][42][PubMed][43] 12. [↵][44]1. H. Vlamakis et al ., Chemtracts 20, 427 (2007). [OpenUrl][45] 13. [↵][46]1. D. B. Kearns et al ., Mol. Microbiol. 55, 739 (2005). [OpenUrl][47][CrossRef][48][PubMed][49][Web of Science][50] 14. [↵][51]1. A. Seminara et al ., Proc. Natl. Acad. Sci. U.S.A. 109, 1116 (2012). [OpenUrl][52][Abstract/FREE Full Text][53] 15. [↵][54]1. H. Vlamakis et al ., Nat. Rev. Microbiol. 11, 157 (2013). [OpenUrl][55][CrossRef][56][PubMed][57] Acknowledgments: A.D.C. and M.P.B. are supported by the National Science Foundation (DMS-1715477), Materials Research Science and Engineering Center (DMR-1420570), the Office of Naval Research (N00014-17-1-3029), and the Simons Foundation. 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News from a postpandemic world

Science

We asked young scientists to imagine this scenario: You are a science writer in the year 2040 working on a news story that answers this question: What do you hope or fear will be the long-term effects of the coronavirus disease 2019 (COVID-19) pandemic? A selection of their responses, arranged as a newpaper, is below. Follow NextGen Voices on Twitter with hashtag #NextGenSci. Read previous NextGen Voices survey results at . —Jennifer Sills Today, scientists confirm that 1000 previously endangered species have been removed from the Vulnerable list. Biodiversity renewal has been under way since the COVID-19 pandemic 20 years ago led many governments to reevaluate their priorities. Hunting practices and bushmeat consumption were constrained to limit the transmission of new pathogens through human contact with the meat and biofluids of wild animals. Deforestation was restricted worldwide when it became clear that land-use modifications and climate change were important drivers of vector-borne diseases. COVID-19 claimed many lives, but the political and environmental changes the pandemic inspired have likely saved many more by protecting the world's biodiversity. Joel Henrique Ellwanger Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, 91501-970, Brazil. Email: joel.ellwanger{at}gmail.com Science and technology research budgets, now classified as an arm of the national defense force, could rival traditional military spending in a few years' time. This newfound prioritization of science was shaped by the COVID-19 pandemic, which made clear that the previous conception of military force is impractical when the enemy is invisible and formidable. The unprecedented redirection of financial resources to scientific communities to help find a cure and vaccines, along with the increased demand for scientific experts, expanded technological frontiers and gave science a well-deserved space in governance. Mpho Diphago Stanley Lekgoathi The South African Nuclear Energy Corporation, Pretoria, Gauteng, South Africa. Email: mpho.lekgoathi{at}necsa.co.za In response to the 50th wave of COVID-19, which hit New York City last month, the U.S. government has announced that the first spaceship designated for in-orbit medical treatment of COVID-19 patients will soon transport 10,000 residents from high-risk zones to Space. Scientists say that prolonged stay in Space colonies with exposure to controlled gamma radiation from cosmic dust may help weaken the virus's strong affinity to lung tissue. “We will do all we can to protect our residents on Earth. Unlike 2019, we are prepared for this challenge,” said the President in a Capitol Hill address. The Senate has voted to fund the treatment expenses for everyone on the flight. Kartik Nemani Layered Materials and Structures Lab, Department of Mechanical and Energy Engineering, Purdue School of Engineering and Technology, Indiana University–Purdue University Indianapolis, Indianapolis, IN 46202, USA. Email: snemani{at}purdue.edu Workers at major corporations staged a walk-out today, the 20th anniversary of the COVID-19 pandemic, to protest what some have deemed invasive monitoring. Many fears subsided when the first SARS-CoV-2 vaccine was broadly distributed in 2023, but subsequent zoonotic viruses emerged faster than society could prepare for them. With the world economy precariously weak, a cautious arrangement was reached: Workers could return to their jobs if they submitted to routine infection checks. At first, these were relatively innocuous temperature probes and cough tracking. However, with the 2029 advent of low-cost RNA wastewater screening by smart toilets and ubiquitous wall-mounted infrared heat sensors, infected employees could be pinpointed before displaying acute symptoms. Later, an eCommerce/fitness-tracking consortium released artificial intelligence algorithms that combined smartwatch health metrics and recent online search history. Corporate Wellness Boards used the results to justify mandatory quarantines. Employees cried foul. The debate rages on in our courts and on the Giganet about whether the public good is served by exposing the “viral status” of the few. Michael A. Tarselli Society for Laboratory Automation and Screening, Oak Brook, IL 60523, USA. Email: mtarselli{at}slas.org Earlier this month, 21 individuals were quarantined in Kampala, Uganda, after a man was diagnosed with Marburg hemorrhagic fever by the local laboratory of the International Center for Disease Prevention (ICDP). The patient, who has now fully recovered, may have been infected at the veterinary clinic where he worked in close contact with possible animal carriers. “This is a virus that spreads easily through bodily fluids and historically has been transmitted to caregivers,” said Dr. Icuaf, director of the ICDP. Once again, the localized presence of centers with efficient testing capabilities made it possible to identify patient zero and contain the outbreak at its inception. As a result, “no deaths occurred, and everyone who might have been exposed has been quarantined while we monitor their health,” added Dr. Icuaf. The ICDP was instituted in 2021 as a global response to the COVID-19 pandemic, which marked a revolution in public awareness of science-based policy. The cost of crisis prevention is now routinely compared with the predicted price of managing such a crisis after it has occurred. Ahmed Al Harraq Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA. Email: aahme22{at}lsu.edu One of the world's leading universities is launching a large-scale screen of potential antiviral and antibacterial drugs on human volunteers. The substances show promising results in vitro but have not been tested on animals. To compensate for the risk of side effects, all volunteers will receive generous payment. “Drugs showing promising effects on mice could be ineffective on humans, making drug development expensive and slow,” explained the leading scientist of the drug screen. Human rights experts warned against granting permission to conduct the study. “Offering payment for causing physical harm targets the economically vulnerable and violates basic human rights,” they argued. However, doctors and politicians praise the idea, referring to the COVID-19 epidemic. “Developing a new drug through the traditional process can take years. Testing multiple potential candidates on coronavirus-infected people saved thousands of lives before basic research had a chance to catch up. Next time, we want to be prepared,” explained the health minister. Anna Uzonyi Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 7610001, Israel. Email: anna.uzonyi{at}weizmann.ac.il Results published today from a 20-year experiment show that a “lottery” grant funding scheme is superior to traditional peer-review assessment panels. For decades, researchers have debated the effectiveness and cost-efficiency of selecting grant recipients through a peer-review process, given the documented biases that hinder diversity and equitable decision-making. “It was a controversial move at the time, but the results are clear,” said the lead author of the study. The funding experiment, which began in 2020 in response to the COVID-19 pandemic, was introduced to preserve the workforce employed on short-term contracts. During that year, pandemic-related budget cuts and social restrictions impeded the traditional peer-review process. “The lottery not only reduced peer-review bias but also added millions of dollars per year to the sector in hours saved by academics no longer devoting time to peer review,” said the lead author. “That time was spent on doing more experiments, mentoring colleagues, or achieving a healthier work-life balance.” Ken Dutton-Regester Department of Genetics and Computational Biology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia. Twitter: @stemventurist As the debate continues on the efficacy of educational methods, most universities now use a combination of in-person, remote, and technology-enhanced classrooms. The rapid expansion of evidence-based strategies such as machine learning and artificial intelligence, audio and video tools, three-dimensional environments, and simulations across disciplines began during the COVID-19 pandemic. The decision to move education to a computer-based environment to protect the health and safety of students and staff transformed the educational conversation. In the increasingly technology-enhanced world, discussions about how to teach a science class online, how to facilitate lab experiences, and how to conduct experiments with new constraints swept the research community. A nuanced understanding emerged about true online pedagogy versus synchronous, remote meetings. Two decades later, we see the results of this transformation. Rachel Yoho Department of Environmental and Global Health, University of Florida, Gainesville, FL 32603, USA. Twitter: @rachel_yoho A stunning 200,000 people attended the grand opening ceremony of the 2040 Olympics yesterday in New Delhi, India. It has been 20 years since such a public event could take place safely. Only with the recent release of clothing and shoes made of technologically advanced materials that instantly kill viruses could the social distancing that began with the COVID-19 pandemic be relaxed. For added peace of mind, all attendees at the ceremony consented to the skin implantation of Viroclean, a new chip-based device that sounds an alarm when it detects viruses in the air. Sudhakar Srivastava Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India. Email: sudhakar.srivastava{at}gmail.com This weekend, at the Coachella 2040 music festival, three aerosol biosurveillance sensors detected a SARS-like virus in the air. Smartphone tracing, using the opt-in U.S. Centers for Disease Control and Prevention (CDC) geospatial health app developed in the wake of the COVID-19 pandemic, identified two potential index cases. The CDC outbreak prevention team mobilized regional contact tracers to intercept and test both individuals within an hour of first detection. One individual tested positive for a variant of the 2019 SARS-CoV-2 strain, previously thought to be eradicated, and is undergoing treatment in quarantine. Michael Strong Center for Genes, Environment, and Health, National Jewish Health and University of Colorado, Anschutz Medical Campus, Denver, CO 80206, USA. Email: strongm{at}njhealth.org Last week's 15th annual Pan-global Remote Integrated Sciences Meeting (PRISM) attracted more than 100,000 attendees from more than 160 countries. Scientists, educators, students, entrepreneurs, policymakers, and industry experts from fields spanning the physical, biological, and social sciences logged on to the online venue, enabled by virtual reality. Advanced machine learning algorithms provided recommendations for presentations relevant to each participant based on both their expertise and potential for interdisciplinary collaboration. As usual, the highlight of the meeting was the virtual poster sessions, driven by interactivity and streamlined to optimize small-group scientific conversation across fields. Many junior scientist attendees were surprised to learn that such events were nearly unheard of before PRISM grew from the increasing move toward virtual conferences during the coronavirus pandemic over 20 years ago. “My adviser told me that when she was a grad student, big conferences were all held in person,” writes one anonymous Ph.D. student. “Can you imagine having a giant conference like this in some random convention center, with tens of thousands of scientists spending hundreds of dollars on fuel-inefficient flights and hotel booking, lugging around printed posters and just milling around for a week trying to find the optimal talks to attend? Insane.” Yifan Li Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA. Twitter: @iWonderWhyly Today, cell-based meat consumption has surpassed farm-produced meat for the first time. The transition began with the meat shortages and near collapse of the meat supply chain during the COVID-19 outbreak. With thousands of workers packed into poorly ventilated and unhygienic facilities, meat processing plants were hotspots for the SARS-CoV-2 virus. A global meat shortage emerged as production rates were slashed. Most people turned to the plant-based meat alternatives available at the time. The meat industry's demise was sealed when cell-based meat entered the mainstream market the following year. Clean meat eliminated the negative effects of the meat industry, from pollution caused by runoff and antibiotics, to worker and animal cruelty, to the carbon footprint of livestock, which contributed 18% of greenhouse gas emissions at the time. Cell-based meat has been growing in popularity ever since, as traditional meat became ethically and environmentally unpalatable. JiaJia Fu Whittle School and Studios, Washington, DC 20008, USA. Email: jjnaturalist{at}gmail.com Global seafood supply now relies entirely on aquaculture. The turning point came when researchers optimized the breeding techniques for edible crabs, enabling high-valued crab species such as mud crabs and blue crabs to be mass-produced in full aquaculture settings. The prioritization of aquaculture was made possible by the COVID-19 pandemic in 2020. A 12-month closure of fisheries during the wave of global stay-at-home orders led to the rejuvenation of overexploited species such as sardines and mackerels, which had been on the verge of extinction, and made people recognize the fragility of the supply chain. Full investment in aquaculture research began the following year. Khor Waiho Institute of Tropical Aquaculture and Fisheries, Universiti Malaysia Terengganu, Kuala Nerus, Terengganu, 21030, Malaysia. Email: waiho{at}umt.edu.my Next week, the United Nations will meet to assess whether the goals of the 2040 Agenda for Sustainable Development have been achieved. Unfortunately, reasons for optimism are scarce. Overexploitation of natural resources, CO2 emissions, and plastic waste continue to soar. The wealthiest sector of the population consumes 80% of the resources, and the poorest people increasingly suffer from extreme weather events, famines, and freshwater scarcity. We were already heading in this direction early in the century, when the short-term vision of corporations and policy-makers prioritized economic benefits over human and environmental health. The COVID-19 pandemic exacerbated the negative trends. Since 2020, an array of wasteful practices increased, including the proliferation of single-use products and travel in private vehicles to avoid physical contact. After reviewing the past decade, the UN countries will discuss commitments to decrease inequality and pollution by 2050. Isabel Marín Beltrán Laboratory of Environmental Technologies, Centro de Ciências do Mar do Algarve, Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Portugal. Email: imbeltran{at}ualg.pt For the first time, global average air temperature is more than 2°C higher than the 20th-century global average. Scientists suggest that decisions made in response to the COVID-19 pandemic led to today's disastrous climate consequences. After the Paris Climate Agreement in 2016, scientists were hopeful. National governments were implementing increasingly ambitious measures to meet their commitments. But the economic fallout of the pandemic led growing economies such as India to relax environmental clearance guidelines for industries and infrastructure projects and cut funding allocated to environmental reforms. First-world countries such as the United States and China, instead of shifting toward renewable energy, boosted investment in fossil fuels, which in turn increased greenhouse gas emissions. Even after multiple warnings from the Intergovernmental Panel on Climate Change, G20 nations neglected to follow the advice of scientists. Akash Mukherjee Department of Physics, Indian Institute of Science Education and Research, Pune, Pune, Maharashtra, 411008, India. Twitter: @aghori_AM A government report released yesterday warns of a potential spike in counterfeit immunity passports entering the market this coronavirus season. According to Jane London, the U.K. health minister, “There is a substantial increase in the number of illegal immunigrants crossing provincial and municipal borders. The public should be aware that just scanning someone's immunity passport is not enough anymore.” This report comes just 6 months after the U.S. Centers for Disease Control and Prevention first released notice that the “NextGen Immunity Passport” brand had been hacked, allowing scammers and tech-savvy citizens to falsify the immunity data they carry with them by law. Asked how businesses and town-guards were detecting falsified immunity passports at checkpoints, minister of national movement John Petersfield told journalists, “This is a police matter. Any further information about detection at this time will only help counterfeiters.” Widespread counterfeiting, as well as last year's false-negative scandal, has generated substantial public distrust in the use of the immunity passport system in movement legislation, now 19 years old. “We learned our lesson about free movement back in 2020,” said one government official who wished to remain anonymous, “but the immunity passport system is cracking, and we don't see a fix yet.” Tyler D. P. Brunet Department of History and Philosophy of Science, University of Cambridge, Cambridge, Cambridgeshire, CB2 3RH, UK. Email: tdpb2{at}cam.ac.uk


AI Hype and Radiology: A Plea for Realism and Accuracy

#artificialintelligence

This opinion piece is inspired by the old Danish proverb: "Making predictions is hard, especially about the future" (1). As every reader knows, the momentum of artificial intelligence (AI) and the eventual implementation of deep learning models seem assured. Some pundits have gone considerably further, however, and predicted a sweeping AI takeover of radiology. Although many radiologists support AI and believe it will enable greater efficiency, a recent study of medical students found very different reactions (2). While such doomsday predictions are understandably attention-grabbing, they are highly unlikely, at least in the short term.


AI For All: The US Introduces New Bill For Affordable Research

#artificialintelligence

Yesterday, AIM published an article on how difficult it is for the small labs and individual researchers to persevere in the high compute, high-cost industry of deep learning. Today, the policymakers of the US have introduced a new bill that will ensure deep learning is affordable for all. The National AI Research Resource Task Force Act was introduced in the House by Representatives Anna G. Eshoo (D-CA) and her colleagues. This bill was met with unanimous support from the top universities and companies, which are engaged in artificial intelligence (AI) research. Some of the well-known supporters include Stanford University, Princeton University, UCLA, Carnegie Mellon University, Johns Hopkins University, OpenAI, Mozilla, Google, Amazon Web Services, Microsoft, IBM and NVIDIA amongst others.


Artificial Intelligence(AI) in Retail Market: Worldwide Survey On Product Need 2026 – 3w Market News Reports

#artificialintelligence

The recent report on "Global Artificial Intelligence(AI) in Retail Market Size, Status and Forecast 2020-2026" offered by Researchmoz.us, Additionally, the report also highlights the challenges impeding market growth and expansion strategies employed by leading companies in the "Artificial Intelligence(AI) in Retail market". This is the most recent report inclusive of the COVID-19 effects on the functioning of the market. It is well known that some changes, for the worse, were administered by the pandemic on all industries. The current scenario of the business sector and pandemic's impact on the past and future of the industry are covered in this report.


Prediction of Overall Rating of a Nursing Home using Machine Learning

#artificialintelligence

The mean, standard deviation, and 75% confidence interval values are maximum for the'Total Amount of Fines in Dollars' feature. The 25% and 50% confidence interval values are maximum for'Number of Certified Beds' and'Average Number of Residents Per Day' columns.


The best weird social distancing tech of 2020 so far

Mashable

Humans are social animals, which is why we can use all the non-human help we can get in our attempts to stop the spread of coronavirus by staying six feet away from each other. To meet the current moment, companies and crafty individuals have developed a number of technological innovations to encourage and enforce social distancing. Some are delightfully low-tech, some are alarmingly intelligent, and others are straight up silly. With cases surging in the U.S. and no vaccine in the in sight, the need to stay socially distant will continue even as people's determination wanes. That's what the robots are for.


Seeing is believing: Effectiveness of facemasks

#artificialintelligence

Currently, there are no specific guidelines on the most effective materials and designs for facemasks to minimize the spread of droplets from coughs or sneezes to mitigate the transmission of COVID-19. While there have been prior studies on how medical-grade masks perform, data on cloth-based coverings used by the vast majority of the general public are sparse. Research from Florida Atlantic University's College of Engineering and Computer Science, just published in the journal Physics of Fluids, demonstrates through visualization of emulated coughs and sneezes, a method to assess the effectiveness of facemasks in obstructing droplets. The rationale behind the recommendation for using masks or other face coverings is to reduce the risk of cross-infection via the transmission of respiratory droplets from infected to healthy individuals. Researchers employed flow visualization in a laboratory setting using a laser light sheet and a mixture of distilled water and glycerin to generate the synthetic fog that made up the content of a cough-jet.


Autonomous bike bots to delivery grub and groceries

ZDNet

Few have, but it's looking increasingly like that may change -- at least for city dwellers in dense urban environments. The footprints of companies offering autonomous mobile robots to deliver food and groceries, while still small, continues to expand thanks to pandemic-related restrictions on dining in and shifting attitudes on contactless service, and companies are jockeying to be the as-a-service robot of choice for consumers and local businesses. We've seen expanding pilot programs announced from nearly every delivery robot developer, and today we add REV-1, a lightweight, bike-like delivery robot from startup Refraction AI, which is offering free delivery within Ann Arbor from grocery store Produce Station. Refraction is the creation of two University of Michigan professors, Matthew Johnson-Roberson and Ram Vasudevan, who say they've developed a safer, more cost-effective solution for last mile logistics than anything in the current delivery paradigm. "We have created the Goldilocks of autonomous vehicles in terms of size and shape," CEO and cofounder Matthew Johnson-Roberson told ZDNet last July.


Bringing the predictive power of artificial intelligence to health care

#artificialintelligence

An important aspect of treating patients with conditions like diabetes and heart disease is helping them stay healthy outside of the hospital -- before they to return to the doctor's office with further complications. But reaching the most vulnerable patients at the right time often has more to do with probabilities than clinical assessments. Artificial intelligence (AI) has the potential to help clinicians tackle these types of problems, by analyzing large datasets to identify the patients that would benefit most from preventative measures. However, leveraging AI has often required health care organizations to hire their own data scientists or settle for one-size-fits-all solutions that aren't optimized for their patients. Now the startup ClosedLoop.ai is helping health care organizations tap into the power of AI with a flexible analytics solution that lets hospitals quickly plug their data into machine learning models and get actionable results.