Culture

The complications of measles can be many and varied, and more serious than people might realise, doctors have warned in the journal BMJ Case Reports after treating a series of adults with the infection.

Measles is a highly contagious respiratory viral infection, the symptoms of which include fever, cough, conjunctivitis, and an extensive rash all over the body.

Measles is entirely preventable as the vaccine used to immunise against it is safe and very effective.

But in the past few decades, unfounded fears about the vaccine have prompted it to re-emerge as a health scourge around the world, with rising numbers of cases in teens and adults, say the authors.

In 2017 the global death toll from measles reached 110,000. Most of these deaths were in young children.

The authors treated three people with measles who had additional complications as a direct result of their infection.

The first case concerned a young man, who had only had the first of two doses of measles vaccine as a child. He was additionally diagnosed with hepatitis.

The second case involved a young woman who developed appendicitis associated with measles. In the third case, a middle aged man complained of blurred vision and severe headache. He was diagnosed with viral meningitis, caused by his measles infection.

All three people recovered fully after appropriate treatment and care, and none had any long lasting health problems as a result of their illness.

But because measles suppresses the immune system, it has been associated with complications in every organ of the body, note the authors. Almost a third of all reported cases are associated with one or more complications, they point out.

These can include pneumonia, febrile seizures, and encephalomyelitis (inflammation of the brain and spinal cord) which causes neurological problems.

Another possible complication of measles is SSPE (subacute sclerosing panencephalitis), a progressive neurological disorder that causes permanent nervous system damage and leads to a vegetative state.

"Large outbreaks with fatalities are currently ongoing in European countries which had previously eliminated or interrupted endemic transmission," write the authors, adding that in the first six months of 2019 alone, 10,000 measles cases were reported in Europe.

They attribute the rise in new cases to negative publicity in the early 2000s linking the measles, mumps and rubella (MMR) vaccine to autism, despite major studies proving otherwise. This prompted a fall in vaccine uptake and collective ('herd') immunity.

"Urgent efforts are needed to ensure global coverage with two-dose measles vaccines through education and strengthening of national immunisation systems," they conclude.

In many industrial and environmental applications, determining the size and distribution of microscopic particles is essential. For example, in the pharmaceutical industry, inline measurement and control of particles containing various chemical ingredients (before consolidation in tablets) may critically enhance the yield and quality of the final medical product. Also, the air we breathe, water we drink and food we eat can also contain many types of unhealthy particulates, which is then crucial to detect for our health and wellbeing.

In a new paper published in Light Science & Application, a team of European scientists and engineers from ICFO and IRIS in Spain, Ipsumio B.V. in the Netherlands, the Technical University of Denmark, the Technische Universität Dresden in Germany and the University of Leeds in the UK, has developed a new micro-particle size analyser by combining consumer electronics products and artificial intelligence. The device, an order of magnitude smaller in terms of size, weight and cost, measures particle size with a precision comparable to commercial light-based particle size analysers at least.

"The EU funded project ProPAT aimed to deliver new sensors for industrial applications. The innovation developed by ICFO is a great example of such sensor. The feedback from pilot scale testing in real world conditions and end-industries moved the sensor from a lab device to potential applicability in industrial environments," says Frans Muller, professor in chemical process engineering at the University of Leeds and the technical manager of ProPAT.

Conventionally, laser diffraction (LD) based particle size analysers (PSA) are widely used for measuring particle size from hundreds of nanometres to several millimetres. In such devices, laser light focused onto a dilute particle sample produces a diffraction (scattering) pattern, measured by an array of light detectors and converted to a particle size distribution using well-established scattering theory. These devices are precise and reliable but large (each dimension being of the order of half meter), heavy (tens of kg) and expensive (often costing in the order of a hundred thousand dollars or more). In addition, their complexity, together with the fact that they often require maintenance and highly trained personnel, make them impractical, for example in the majority of online industrial applications, which require installation of probes in processing environments, often at multiple locations.

The newly developed PSA works in a collimated beam configuration using a simple LED light emitting diode (LED) and a single metal-oxide-semiconductor (CMOS) image sensor, similar to those used in smart phones. The key-innovation is the small angular spatial filter (ASF) made with an array of holes with different diameters that is extruded from a polymer rod. On illuminating the target sample, light scatters and passes through the ASF onto the sensor. Light collected from different size holes is representative of a different set of scattering angles. An ad hoc machine learning (ML) model converts the sensor image into size of particles. The same device can be easily converted into hazemeter, an essential instrument to characterize many optical materials.

"It is very exciting to see how a simple combination of consumer photonic components, such as an LED and a phone camera, an innovative angular filter fabricated using mass-scalable photonic crystal fiber extrusion and machine learning data processing has allowed us to make such a compact, cheap and precise device", says Rubaiya Hussain, first author of the paper and PhD candidate in the Optoelectronics group at ICFO.

In order to validate the new PSA, mixtures of water and glass beads with sizes in the range from 13 to 125 micrometre were tested at several process concentrations in liquid dispersions. Laser diffraction systems cannot measure such high concentrations as light is scattered multiple times resulting in scattering patterns that cannot be converted into particles size. Using the random forest machine learning algorithm the data from the new device could be analysed successfully, increasing the working range of particle sizes and concentrations that can be measured.

"We used the PSA device built at ICFO in Barcelona to collect data from different particle size ranges and concentrations of standard glass beads. According to the obtained results and our experience, we were pleased to see that the precision of a few % of the median volume particle size (D50) is comparable with other measurement techniques (e.g. LD) in micrometre range", says Dipl.-Ing. Rodrigo R. Retamal Marín, researcher in the Mechanical Process Engineering group at theTechnische Universität Dresden.

Future improvements in the optical hardware are also being designed. In particular, further optimisation of the innovative ASF component and refined data capturing methods are being undertaken, to produce larger, higher fidelity datasets for the machine learning algorithm. Future work will also include analysis of non-spherical particles, collected with well-designed sample feeding systems for both dry and wet measurements, leading to high precision analysis for a range of industrially relevant systems.

"We intend to utilize the inherent flexibility of the simple design and low hardware cost of our proprietary PSA for specific applications, for example online or at-line monitoring, and we are looking for partners from various Industries and Research Institutions", says Valerio Pruneri, ICREA Professor at ICFO and leading author of the work.

What The Study Did: Patients with chronic life-limiting illnesses often have medical orders with treatment limitations in place regarding medical interventions and intensive care unit admissions near the end of their lives. This observational study included about 1,800 patients with such orders who were hospitalized within six months of their death to examine how often care was consistent with those orders.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

Authors: Robert Y. Lee, M.D., M.S., of the University of Washington in Seattle, is the corresponding author.

(doi:10.1001/jama.2019.22523)

Editor's Note: The article includes conflict of interest and funding/support disclosures. Please see the articles for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

EVANSTON, Ill. --- A wife-husband team will present both high-tech and low-tech solutions for improving water security at this year's American Association for the Advancement of Science (AAAS) annual meeting in Seattle on Sunday, Feb. 16. Northwestern University's Sera Young and Julius Lucks come from different ends of the science spectrum but meet in the middle to provide critical new information to approach this global issue.

Lucks, associate professor of chemical and biological engineering in Northwestern's McCormick School of Engineering and an internationally recognized leader in synthetic biology, is developing a new technology platform to allow individuals across the globe to monitor the quality of their water cheaply, quickly and easily. Lucks will discuss how advances made at Northwestern's Center for Synthetic Biology are making these discoveries possible in his presentation "Rapid and Low-cost Technologies for Monitoring Water Quality in the Field."

In "A Simple Indicator of Global Household Water Experiences," Young, associate professor of anthropology in Northwestern's Weinberg College of Arts and Sciences, will discuss the Household Water Insecurity Experiences Scale (HWISE.org), the first globally equivalent scale to measure experiences of household-level water access and use. Young led a large consortium of scholars in the development of the HWISE Scale, which permits comparisons across settings to quantify the social, political, health and economic consequences of household water insecurity. The HWISE Scale is already being used by scientists and governmental- and non-governmental organizations around the world, including the Gallup World Poll.

Both presentations will be presented with representatives from the World Bank and UNESCO as part of the session "Managing Water: New Tools for Sustainable Development" to be held from 3:30 to 5 p.m. on Sunday, Feb. 16, at the Washington State Convention Center.

Prior to the 3:30 p.m. panel on Sunday, Young and Lucks will participate in an Expo Stage Debrief: "Managing Water: New Tools for Sustainable Development?" which will be held at 11:30 a.m. in the Expo Hall at the convention center. The discussion will be livestreamed.

For all the benefits in the expansion of the media landscape, we're still struggling with the spread of misinformation--and the damage is especially worrisome when it comes to information about science and health.

"Believing things that aren't true when it comes to health can be not just bad for us, but dangerous," said Dan Gillmor, co-founder of the News Co/Lab at Arizona State University's Walter Cronkite School of Journalism and Mass Communication. "Journalists have a special duty to avoid being fooled, and they can help us learn to sort out truth from falsehood ourselves."

Gillmor will discuss his work, which focuses on improving media literacy, during a panel presentation on Feb. 15 as part of the annual meeting of the American Association for the Advancement of Science (AAAS) in Seattle, Washington.

His presentation is anchored by warnings from security experts, aimed at media consumers and journalists who may sometimes unwittingly amplify bad information. Those experts label journalism as an "attack surface" for those who are looking to intentionally spread misinformation.

His discussion is particularly timely as the country moves into the 2020 election season, when the stakes become higher on local and national levels.

"We need to get better ourselves at sorting out what we can trust, and understanding our roles as part of a digital ecosystem in which we're sharers and creators as well as consumers," Gillmor said.

The News Co/Lab, which has received support from the Facebook Journalism Project, Craig Newmark Philanthropies, Democracy Fund, Rita Allen Foundation and News Integrity Initiative, collaborates with a number of partners to find new ways to increase public understanding of the news. Research suggests expertise in the area is sorely needed.

A report released by the News Co/Lab and the Center for Media Engagement at The University of Texas at Austin revealed that nearly a third of media consumers with a college education could not identify a fake news headline. And, consumers with negative attitudes about the news media were less likely to be able to spot fake news or distinguish opinion from analysis or advertising.

Gillmor's presentation will pivot on the need for a better understanding of news and the media, how journalists can prepare for and respond to misinformation, and how consumers can learn to parse what they read and watch so that they don't unknowingly traffic information that was intentionally designed to be misleading. For its part, the News Co/Lab recently received a grant for a new media literacy project that will include outreach events across the U.S., a massive online open course on digital media literacy, and digital and social media content.

Psychological tests are important instruments used in courts to aid legal decisions that profoundly affect people's lives. They can help determine anything from parental fitness for child custody, to the sanity or insanity of a person at the time of a crime, to eligibility for capital punishment.

While increasingly used in courts, new research shows the tests are not all scientifically valid, and once introduced into a case they are rarely challenged, according to Tess Neal, an assistant professor of psychology at Arizona State University.

"Given the stakes involved one would think the validity of such tests would always be sound," Neal said. "But we found widespread variability in the underlying scientific validity of these tests."

The problem is made worse because the courts are not separating the good from the bad.

"Even though courts are required to screen out 'junk science,' nearly all psychological assessment evidence is admitted into court without even being screened," Neal said.

Neal was speaking today (February 15) at the annual meeting of the American Association for the Advancement of Science in Seattle. She presented her findings in the talk "Psychological assessments and the law: Are courts screening out "junk science?"

In a two-part investigation, Neal and her colleagues found a varying degree of scientific validity to 364 commonly used psychological assessment tools employed in legal cases. The researchers looked at 22 surveys of experienced forensic mental health practitioners to find which tools are used in court. With the help of 30 graduate students and postdocs, they examined the scientific foundations of the tools, focusing on legal standards and scientific and psychometric theory.

The second part of the study was a legal analysis of admissibility challenges with regard to psychological assessments, focusing on legal cases from across all state and federal courts in the U.S. for a three-year period (2016-2018).

"Most of these tools are empirically tested (90%), but we could only clearly identify two-thirds of them being generally accepted in the field and only about 40% as having generally favorable reviews of their psychometric and technical properties in authorities like the Mental Measurements Yearbook," Neal explained.

"Courts are required to screen out the 'junk science,' but rulings regarding psychological assessment evidence are rare. Their admissibility is only challenged in a fraction of cases (5.1%)," Neal said. "When challenges are raised, they succeed only about a third of the time."

"Challenges to the most scientifically suspect tools are almost nonexistent," Neal added. "Attorneys rarely challenge psychological expert assessment evidence, and when they do, judges often fail to exercise the scrutiny required by law."

What is needed is a different approach. In their open-access paper in Psychological Science in the Public Interest, Neal and her colleagues offer concrete advice for solving these problems to psychological scientists, mental health practitioners, lawyers, judges and members of the public interacting with psychologists in the legal system.

"We suggest that before using a psychological test in a legal setting, psychologists ensure its psychometric and context-relevant validation studies have survived scientific peer review through an academic journal, ideally before publication in a manual," Neal explained. "For lawyers and judges, the methods of psychologist expert witnesses can and should be scrutinized, and we give specific suggestions for how to do so."

In television crime dramas, savvy lawyers are able to overcome improbable odds to win their cases by presenting seemingly iron-clad scientific evidence. In real-world courtrooms, however, the quality of scientific testimony can vary wildly, making it difficult for judges and juries to distinguish between solid research and so-called junk science.

This is true for all scientific disciplines, including psychological science, which plays an important role in assessing such critical pieces of testimony as eyewitness accounts, witness recall, and the psychological features of defendants and litigants.

A new, multiyear study published in Psychological Science in the Public Interest (PSPI), a journal of the Association for Psychological Science (APS), finds that only 40% of the psychological assessment tools used in courts have been favorably rated by experts. Even so, lawyers rarely challenge their conclusions, and when they do, only one third of those challenges are successful.

"Although courts are required to screen out junk science, legal challenges related to psychological-assessment evidence are rare," said Tess M.S. Neal of Arizona State University, one of the authors of the report. The other authors are Michael J. Saks of Arizona State University, Christopher Slobogin of Vanderbilt University Law School, David Faigman of the University of California Hastings School of Law, and Kurt F. Geisinger of the University of Nebraska-Lincoln.

"Although some psychological assessments used in court have strong scientific validity, many do not. Unfortunately, the courts do not appear to be calibrated to the strength of the psychological-assessment evidence," said Neal.

The new APS report examines more than 360 psychological assessment tools that have been used in legal cases, along with 372 legal cases from across all state and federal courts in the United States during the calendar years 2016, 2017, and 2018.

These findings are also presented at the 2020 American Association for the Advancement of Science (AAAS) meeting in Seattle.

Psychological scientists provide expert evidence in a variety of court proceedings, ranging from custody disputes to disability claims to criminal cases. In developing their expert evaluation of, for example, a defendant's competence to stand trial or a parent's fitness for child custody, they may use tools that measure personality, intelligence, mental health, social functioning, and other psychological features. A number of federal court decisions and rules give judges the latitude to gauge the admissibility of evidence, largely by evaluating its empirical validity and its acceptance within the scientific community.

For their review, Neal and her colleagues gathered results from 22 surveys of psychologists who serve as forensic experts in legal cases. They reviewed the 364 psychological assessment tools that the respondents reported having used in providing expert evidence. They found that nearly all of those tools have been subjected to scientific testing, but only about 67 percent are generally accepted by the psychological community at large. What's more, only 40% of the tools have generally favorable reviews in handbooks and other sources of information about psychological tests.

The scientists also found that legal challenges to the admission of assessment evidence are rare, occurring in only about 5% of cases they reviewed. And only a third of those challenges succeeded.

According to the report: "Attorneys rarely challenge psychological expert assessment evidence, and when they do, judges often fail to exercise the scrutiny required by law."

In an accompanying commentary, David DeMatteo, Sarah Fishel, and Aislinn Tansey, psychology and legal scholars at Drexel University, call for more research on whether trial court judges are functioning as effective gatekeepers for expert testimony. They point to studies indicating that many judges admit evidence from methodologically flawed studies and others that show attorneys and jurors lack the scientific literacy necessary to scrutinize scientific evidence. The Drexel scholars also called on forensic psychologists to ensure they use scientifically sound assessment tools when providing expert evaluations in legal settings.

Why do predators sometimes lay dormant eggs -- eggs which are hardy, but take a long time to hatch, and are expensive to produce?

That is the question that researchers from Singapore University of Technology and Design (SUTD) set out to answer in a recent paper published in Advanced Science, a cutting-edge research journal with an impact factor of 15.804 (2019 Journal Citation Reports).

The traditional answer is that these hardy eggs allow the population to survive harsh environmental conditions, like winter or drought. However, this does not explain why dormant eggs are laid even in non-seasonal habitats, such as tropical lakes.

The team of researchers led by Assistant Professor Kang Hao Cheong from SUTD, in collaboration with Dr Eugene V. Koonin, senior investigator at the National Institutes of Health, have discovered an alternate explanation: Dormancy is a naturally occurring response to over-predation. In non-seasonal habitats, prey organisms, such as algae in a lake, grow to very large populations. This leads their predators, such as zooplankton, to consume them at a high rate and grow in population as well. Eventually, this leads to over-consumption. As the algae population collapses, little food is left for the large amount of zooplankton, which then begin to starve and die.

It is during this period of food scarcity that dormancy makes a lot of sense. If a zooplankton had laid hardy, slow-hatching dormant eggs in advance, those eggs would likely hatch after the prey populations had recovered, allowing them to survive and reproduce. On the other hand, if the zooplankton had only laid regular fast-hatching eggs, those eggs would likely hatch in the middle of the famine, and would not aid much in the recovery of the zooplankton population. Eventually, only those zooplankton which lay dormant eggs would dominate the population.

In discovering this explanation, the researchers were inspired by a phenomenon called Parrondo's paradox. The paradox states that it is possible to alternate between a pair of losing strategies, such as losing bets in a gamble, and still end up winning. When food is plenty, the researchers realized that dormancy is similarly paradoxical.

"Why spend extra energy laying dormant eggs, when your competitors are saving energy by laying regular eggs? And why invest in eggs that take longer to hatch, when your competitors are laying eggs that will hatch faster and grow quickly into adults? That was what we needed to explain," said Zhi-Xuan Tan, the lead author of the study. "Just like in Parrondo's paradox, we had a pair of losing strategies: the strategy of laying dormant eggs, and the strategy of remaining dormant as an egg instead of hatching."

As the researchers discovered, switching between these two losing strategies ensures survival against the food shortages created by over-predation.

The implications of this study could go beyond explaining why predators lay dormant eggs. "One of the first applications of Parrondo's paradox was actually to explain a biological process: how molecular motors in our muscles could produce sustained directional movement", observed Assistant Professor Kang Hao Cheong from SUTD, the principal investigator for this study. "We believe that the relevance of Parrondo's paradox to biology might be wider still."

For example, the researchers suggest that Parrondo's paradox might also explain why bacteria-infecting viruses often alternate between a dormant lysogenic phase, where viruses incorporate their DNA into the bacterial genome, and an active and infectious lytic phase, which kills bacteria.

"Going further, we might even be able to explain the evolution of multicellular life," said Assistant Professor Cheong. "How did unicellular organisms start co-operating enough to form multicellular organisms, when cheating and taking advantage of other cells could often yield better results? As co-operation is a losing strategy in this context, we suspect that Parrondo's paradox might one day yield some answers."

All organisms on our planet store the molecular blueprint of life in a DNA code within their genome. The digital revolution in biology, driven by DNA sequencing, enables us to read the genomes of the myriads of microbes and multi-cellular organisms that populate our world. Today, the DNA sequences of over 200,000 microbial genomes are deposited in digital genome databases and have exponentially increased our understanding of how DNA programs living systems. Using this incredible treasure trove of molecular building blocks, bio-engineers learn to read (sequence) and write (using chemical synthesis) long DNA molecules and to breed useful microbes with the help of computers.

In his research, Beat Christen, Professor of Experimental Systems Biology and researchers in the Christen Lab, ETH Zurich in Zurich, Switzerland use a digital genome design algorithm in conjunction with large-scale chemical DNA synthesis to physically produce artificial genomes and understand the code of life at the molecular level. The lab also uses systems and synthetic biology approaches to define essential genes across species that serve as the genetic parts to build microbial genomes for applications in sustainable chemistry, medicine and agriculture.

The research team has physically produced Caulobacter ethensis-2.0, the world's first fully computer-generated genome. Using a natural freshwater bacterium as a starting point, the researchers computed the ideal DNA sequence for chemical manufacturing and construction of a minimized genome solely comprised of essential functions. In the design process, more than one-sixth of all of the 800,000 DNA letters in the artificial genome were replaced and the entire genome was produced as a large ring-shaped DNA molecule. While a living cell does not yet exist, gene functions have been tested across the entire genome design. In these experiments, researchers found out that approximately 580 of the 680 artificial genes were functional demonstrating the promise of the approach to produce designer genomes.

During the AAAS 2020 session, "Synthetic Biology: Digital Design of Living Systems" (February 14th, 2020 at 3:30 PM PST), Christen will discuss possible future applications of synthetic genomes for industrial purposes and health benefits. He will also talk about the need for profound discussions in society about the challenges and purposes for which this technology can be used and, at the same time, about how potential for abuse can be prevented.

Professor Christen will be joined by Professor David Baker, University of Washington who will speak about Designer Proteins and Joyce Tait, University of Edinburgh, Edinburgh Scotland, who will speak on Risk Regulation, Uncertainty, and Ethics.

A study led by Susan Tsang, a former Fulbright Research Fellow from The City College of New York, reveals dwindling populations and widespread hunting throughout Indonesia and the Philippines of the world's largest bats, known as flying foxes.

Unfortunately, hunting not only depletes the flying foxes, which are already rare, but also potentially exposes humans to animal-borne pathogens (a process known as zoonosis). "For instance, the current case of Wuhan Coronavirus is thought to have been spread from wild bats to humans through an intermediate host at a wildlife market," said CCNY biologist and Tsang's mentor David J. Lohman, an entomologist and two-time Fulbright recipient.

The CCNY experts found that flying foxes originated in a group of islands in Indonesia called Wallacea. They diversified into different species by flying to other islands that presumably lacked competitors and established themselves. Thus, islands are critical to the evolution and conservation of this large group of around 65 mammal species.

"This study provides insight into biodiversity conservation and public health. Islands are frequently home to endemic species found nowhere else," noted Tsang, who earned a PhD in biology from the Graduate Center, CUNY.

Unfortunately, island-endemic species are more likely to be endangered or go extinct than continental species. Flying foxes are seed dispersers and pollinators of many ecologically and economically important plants, and forest trees on islands often depend on bats for regeneration.

In a study with potentially far-reaching implications for criminal justice in the United States, a team of California researchers has found that algorithms are significantly more accurate than humans in predicting which defendants will later be arrested for a new crime.

When assessing just a handful of variables in a controlled environment, even untrained humans can match the predictive skill of sophisticated risk-assessment instruments, says the new study by scholars at Stanford University and the University of California, Berkeley.

But real-world criminal justice settings are often far more complex, and when a larger number of factors are useful for predicting recidivism, the algorithm-based tools performed far better than people. In some tests, the tools approached 90% accuracy in predicting which defendants might be arrested again, compared to about 60% for human prediction.

"Risk assessment has long been a part of decision-making in the criminal justice system," said Jennifer Skeem, a psychologist who specializes in criminal justice at UC Berkeley. "Although recent debate has raised important questions about algorithm-based tools, our research shows that in contexts resembling real criminal justice settings, risk assessments are often more accurate than human judgment in predicting recidivism. That's consistent with a long line of research comparing humans to statistical tools."

"Validated risk-assessment instruments can help justice professionals make more informed decisions," said Sharad Goel, a computational social scientist at Stanford University. "For example, these tools can help judges identify and potentially release people who pose little risk to public safety. But, like any tools, risk assessment instruments must be coupled with sound policy and human oversight to support fair and effective criminal justice reform."

The paper -- "The limits of human predictions of recidivism" -- was slated for publication Feb. 14, 2020, in Science Advances. Skeem presented the research on Feb. 13 in a news briefing at the annual meeting of the American Association for the Advancement of Science (AAAS) in Seattle, Wash. Joining her were two co-authors: Ph.D. graduate Jongbin Jung and Ph.D. candidate Zhiyuan "Jerry" Lin, who both studied computational social science at Stanford.

The research findings are important as the United States debates how to balance the needs communities have for security while reducing incarceration rates that are the highest of any nation in the world--and disproportionately affect African Americans and communities of color.

If the use of advanced risk assessment tools continues and improves, that could refine critically important decisions that justice professionals make daily: Which individuals can be rehabilitated in the community, rather than in prison? Which could go to low-security prisons, and which to high-security sites? And which prisoners can safely be released to the community on parole?

Assessment tools driven by algorithms are widely used in the United States, in areas as diverse as medical care, banking and university admissions. They have long been used in criminal justice, helping judges and others to weigh data in making their decisions.

But in 2018, researchers at Dartmouth University raised questions about the accuracy of such tools in a criminal justice framework. In a study, they assembled 1,000 short vignettes of criminal defendants, with information drawn from a widely used risk assessment called the Correctional Offender Management Profiling for Alternative Sanctions (COMPAS).

The vignettes each included five risk factors for recidivism: the individual's sex, age, current criminal charge, and the number of previous adult and juvenile offenses. The researchers then used Amazon's Mechanical Turk platform to recruit 400 volunteers to read the vignettes and assess whether each defendant would commit another crime within two years. After reviewing each vignette, the volunteers were told whether their evaluation accurately predicted the subject's recidivism.

Both the people and the algorithm were accurate slightly less than two-thirds of the time.

These results, the Dartmouth authors concluded, cast doubt on the value of risk-assessment instruments and algorithmic prediction.

The study generated high-profile news coverage--and sent a wave of doubt through the U.S. criminal justice reform community. If sophisticated tools were no better than people in predicting which defendants would re-offend, some said, then there was little point in using the algorithms, which might only reinforce racial bias in sentencing. Some argued such profound decisions should be made by people, not computers.

Grappling with "noise" in complex decisions

But when the authors of the new California study evaluated additional data sets and more factors, they concluded that that risk assessment tools can be much more accurate than people in assessing potential for recidivism.

The study replicated the Dartmouth findings that had been based on a limited number of factors. However, the information available in justice settings is far more rich -- and often more ambiguous.

"Pre-sentence investigation reports, attorney and victim impact statements, and an individual's demeanor all add complex, inconsistent, risk-irrelevant, and potentially biasing information," the new study explains.

The authors' hypothesis: If research evaluations operate in a real-world framework, where risk-related information is complex and "noisy," then advanced risk assessment tools would be more effective than humans at predicting which criminals would re-offend.

To test the hypothesis, they expanded their study beyond COMPAS to include other data sets. In addition to the five risk factors used in the Dartmouth study, they added 10 more, including employment status, substance use and mental health. They also expanded the methodology: Unlike the Dartmouth study, in some cases the volunteers would not be told after each evaluation whether their predictions were accurate. Such feedback is not available to judges and others in the court system.

The outcome: Humans performed "consistently worse" than the risk assessment tool on complex cases when they didn't have immediate feedback to guide future decisions.

For example, the COMPAS correctly predicted recidivism 89% of the time, compared to 60% for humans who were not provided case-by-case feedback on their decisions. When multiple risk factors were provided and predictive, another risk assessment tool accurately predicted recidivism over 80% of the time, compared to less than 60% for humans.

The findings appear to support continued use and future improvement of risk assessment algorithms. But, as Skeem noted, these tools typically have a support role. Ultimate authority rests with judges, probation officers, clinicians, parole commissioners and others who shape decisions in the criminal justice system.

Research by an international team of scientists led by University of New Mexico Professor Yemane Asmerom suggests contraction of the Intertropical Convergence Zone (ITCZ) during a warming Earth, leading in turn to drying of the Neotropics, including Central America, and aggravating current trends of social unrest and mass migration.

Positioned near the equator where the trade winds of the northern and southern hemisphere converge, the ITCZ is the world's most important rainfall belt affecting the livelihood of billions of people around the globe. Globally, seasonal shifts in the location of the ITCZ across the equator dictate the initiation and duration of the tropical rainy season. The behavior of the ITCZ in response to the warming of the Earth is of vital scientific and societal interest.

Previous work based on limited data suggested a southward migration of the ITCZ in response to global cooling, such as during the Little Ice Age a few hundred years ago. In contrast, modeling and limited observational data seemed to suggest the ITCZ expands and contracts in response to cooling and warming. Which of these scenarios is correct has a huge implication for understanding rainfall variability and its economic and social impacts across the tropics. In order to resolve these seemingly contradictory alternatives the authors undertook this paleoclimate reconstruction study from the margin of the ITCZ and combined that with existing data from across the full annual north-south excursion of the ITCZ.

The study titled, "Intertropical Convergence Zone Variability in the Neotropics During the Common Era," was published today in Science Advances. In addition to UNM, the research also includes scientists from the University of Durham (UK), Northumbria University (UK) and the University of California, Santa Barbara.

"Much of our understanding of ITCZ variability was based on records from South America, especially the Cariaco Basin (Venezuela), which was the gold standard," explained Asmerom. "But these studies were only able to present half of the picture. As a result, they suggested southward movement of the mean position of the ITCZ during cool periods of Earth, such as during the Little Ice Age, and by implication it shifts northward during warm periods.

"This would imply regions in the northern margin of the ITCZ, such as Central America would get wetter with warming climate. This contradicted modeling results suggesting drying as a consequence of warming."

With two testable hypotheses, Asmerom and his colleagues used 1,600 years of new bimonthly-scale speleothem rainfall reconstruction data from a cave site located at the northern margin of the ITCZ in Central America, coupled with published data from the full transect of the ITCZ excursion in Central America and South America. The combined data elucidate ITCZ variability throughout the Common Era including the warmer Medieval Climate Anomaly and the cooler Little Ice Age. The results of this study are consistent with models suggesting ITCZ expansion and weakening during global periods of cold climate and contraction and intensifying during periods of global warmth.

"Stable isotopic data obtained at Durham University, and trace element data and a precise uranium-series chronology, with an average 7 year uncertainty, obtained at the University of New Mexico, provided us with a nearly bi-monthly record of past climate variability between 400 CE to 2006. This level of resolution is unprecedented for continental climate proxies", said Polyak.

"What we found was that in fact during the Medieval Climate Anomaly Southern Belize was very dry, similar to modern central Mexico. In contrast, during the Little Ice Age cool period, when it should have been dry by the standard old model, it was the wettest interval over the last 2000 years," said Asmerom. "The pattern that emerges when all the data across the full transect of ITCZ excursion is supportive of the expansion-contraction model." The implication of this that regions currently in the margins of the ITCZ are likely to experience aridity with increased warming, consistent with modeling data from Central America. These data have important implications for rainfall-dependent agriculture system on which millions of people depend for food security.

Co-author and UNM Professor of Anthropology Keith Prufer is an environmental archaeologist, who has been conducting research in Belize for 25 years. "In the last five years there have been mass migrations of people in Guatemala and Honduras - partially driven by political instability, but also driven by drought-related conditions and changes in seasonality. This is creating enormous problems for agricultural production and feeding a growing population. There is growing evidence that these changes are a direct consequence of climate change."

"This work highlights the convergence of good science with policy relevancy. It also illustrates the strength of cross-disciplinary collaborative work, in this case international," said Asmerom.

Alzheimer's disease (AD) is progressive, but slow to develop -- or at least to reveal itself. In a new study, published online February 14, 2020 in the journal Biological Psychiatry, researchers at University of California San Diego School of Medicine, with colleagues elsewhere, report that early, subtle differences in cognitive performance, such as fewer words recalled on a memory test, are a sign that harmful proteins are accumulating in the brain, even if levels of those proteins do not yet qualify as dangerous.

Pathologically, AD is primarily characterized by the accumulation of protein plaques called β-amyloid (Aβ), which gradually accumulate in the brain, disrupting cell function and eventually killing affected neurons. A second type of protein, called tau, also accumulates abnormally inside neurons, damaging functions.

In the progression of AD, Aβ levels build in the brain, but the process leading to abnormally high levels is typically long. It is often years or decades before consequential symptoms of severe cognitive impairment appear. A new framework from the National Institute on Aging and Alzheimer's Association defines the first stage of AD to be individuals with abnormal levels of Aβ who are still cognitively normal.

"Although AD pathology, and Aβ in particular, appear long before severe cognitive deficits appear," said first author Jeremy A. Elman, PhD, assistant professor in the Department of Psychiatry at UC San Diego School of Medicine, "recent evidence suggests more subtle cognitive changes may appear earlier in the disease than commonly appreciated."

Elman and colleagues, including senior author William S. Kremen, PhD, professor of psychiatry at UC San Diego School of Medicine, sought to determine whether poor cognitive performance, however subtle, might be a predictor that current Aβ-negative levels (accumulations below the threshold for AD diagnosis) were likely to become Aβ-positive.

"Once a person reaches the point of being Aβ-positive, it means that there is already substantial underlying pathology," said Kremen. "It would be advantageous to identify at-risk individuals before they develop substantial amyloid burden to improve treatment efficacy and slow progression to AD dementia."

The researchers conducted a pair of non-invasive cognitive tests on 292 participants in the Alzheimer's Disease Neuroimaging Initiative, an ongoing study to assess whether the use of medical imaging, biological markers and clinical assessments can be combined to measure the progression of cognitive decline and early AD.

All of the participants were Aβ-negative at baseline testing and displayed no dementia; 40 participants would progress to Aβ-positivity during the study and follow-up period.

The scientists found that participants who tested with lower baseline cognition were at significantly higher risk of progressing to Aβ-positivity. That is, low test scores indicating poorer cognitive function suggested amyloid plaque levels that, while not yet considered to be problematic, were likely rising and would ultimately reach the threshold definition of AD.

"We found that subthreshold levels of baseline Aβ were predictive of future accumulation, adding to evidence that even low levels of Aβ are clinically relevant, but that cognitive performance was still significantly predictive even after controlling for this pathology," said Elman.

The findings, wrote the researchers, suggest that low-cost, non-invasive cognitive testing is useful for identifying persons who may be at risk for developing AD, making them ideal candidates for therapeutic intervention and clinical trials.

MISSOULA - Every social network has its fake news. And in animal communication networks, even birds discern the trustworthiness of their neighbors, a study from the University of Montana suggests.

The study, recently published in the top science journal Nature, is the culmination of decades' worth of research from UM alumni Nora Carlson and Chris Templeton and UM Professor Erick Greene in the College of Humanities and Sciences. It sheds a new light on bird social networks.

"This is the first time people have shown that nuthatches are paying attention to the source of information, and that influences the signal they produce and send along," Greene said.

Carlson, Templeton and Greene shared an interest in trying to crack the Rosetta Stone of how birds communicate and collected bird calls over the years.

Each bird species has a song, usually sung by the males, for "letting the babes know 'here I am,'" Greene said, as well as staking out real estate. Their loud and complex calls usually ring out during breeding season.

But for warning calls, each sound stands for a specific threat, such as "snake on the ground," "flying hawk" and "perched hawk." The calls convey the present danger level and specific information. They also are heard by all species in the woods in a vast communication network that sets them on high alert.

"Everybody is listening to everybody else in the woods," Greene said.

In the study, Greene and his researchers wanted to determine how black-capped chickadees and red-breasted nuthatches encode information in their calls.

In bird communication, a high-pitched "seet" from a chickadee indicates a flying hawk and causes a strong reaction - other birds go silent, look up and then dive in the bushes. Alarm calls can travel quickly through the woods. Greene said in previous experiments they clocked the speed of the calls at 100 miles per hour, which he likens to the bow wave on a ship.

"Sometimes birds in the woods know five minutes before a hawk gets there," Greene said.

A harsh, intensified "mobbing call" drives birds from all species to flock together to harass the predator. When the predator hears the mobbing call, it usually has to fly a lot farther to hunt, so the call is very effective.

"The owl is sitting in the tree, going, 'Oh crap!" Greene said.

Greene calls it "social media networks - the original tweeting."

For the study with chickadees and nuthatches, the researchers focused on direct information - something a bird sees or hears firsthand - versus indirect information, which is gained through the bird social network and could be a false alarm.

"In a way, it kind of has to do with fake news, because if you get information through social media, but you haven't verified it, and you retweet it or pass it along, that's how fake news starts," Greene said.

Nuthatches and chickadees share the same predators: the great-horned owl and the pygmy owl. To the small birds, the pygmy owl is more dangerous than a great-horned owl due to its smaller turning radius, which allows it to chase prey better.

"If you are eating something that's almost as big as you are, it's worth it to go after it," Greene said.

Using speakers in the woods, the researchers played the chickadee's warning call for the low-threat great-horned owl and the higher-threat pygmy owl to nuthatches. The calls varied by threat level - great-horned owl versus pygmy owl - and whether they were direct (from the predators themselves) or indirect (from the chickadees).

What they discovered about the nuthatches was surprising.

Direct information caused the nuthatches to vary their calls according to the high threat and the low threat. But the chickadee's alarm call about both predators elicited only a generic, intermediate call from the nuthatch, regardless of the threat level.

Greene said the research points to the nuthatch's ability to make sophisticated decisions about stimuli in their environment and avoid spreading "fake news" before they confirm a predator for themselves.

"You gotta take your hat off to them," Greene said. "There's a lot of intelligence there."

The research, conducted by Carlson, Templeton and Greene around Montana and Washington throughout the years, wasn't without challenges.

Most of the set up happened during winter, and nuthatches had to be isolated from chickadees to ensure the warning calls were not a response to witnessing chickadees going crazy. Often a chickadee would appear after everything was set up, and the researchers had to take everything down and try a new location.

"It's quite hard to find nuthatches without chickadees somewhere in the area," Greene said. "That was the most difficult part - to find these conditions out in the wild."

But the results were worth the work.

Greene said the nuthatch study ultimately helps researchers better understand how animal communication networks work and how different species decode information, encode info and pass it along.

"We kind of wish people behaved like nuthatches," Greene said.

Seagrasses have long been known as some of Earth's most remarkable organisms--descendants of flowering land plants that have re-colonized the ocean by developing traits that allow them to grow, pollinate, and release seeded fruits while fully immersed in salty seawater.

Now, research by a joint Australian-U.S. team reveals that one group of seagrasses, Australian species of the genus Posidonia, have evolved yet another remarkable adaptation for ocean survival: a winged seed whose shape harnesses the force of underwater currents to hold it on the seafloor for rooting.

Results of the study offer valuable insights for efforts to restore seagrass populations in Australia, the Chesapeake Bay, and elsewhere. Seagrass meadows, which provide important nursery and feeding habitat for other marine life and play a key role in maintaining water quality, are under threat worldwide from warming and over-fertilization of coastal waters.

Published in a recent issue of Scientific Reports, the seagrass study is the first to record a winged seed among marine angiosperms, and to experimentally determine its adaptive benefit. It also shows that seeds of Posidonia species in areas with stronger currents have larger wings, further evidence of the trait's utility.

Lead author on the report was Dr. Gary Kendrick of the University of Western Australia. The research emerged from a long-term collaboration between Kendrick and Dr. Robert "JJ" Orth of William & Mary's Virginia Institute of Marine Science, a pioneer in monitoring and restoring seagrasses in the Chesapeake Bay and mid-Atlantic coastal lagoons. Also contributing to the study were Marion Cambridge, Jeremy Shaw, Lukasz Kotula, and Ryan Lowe of UWA and Andrew Pomeroy of the Australian Institute for Marine Science.

"Understanding the basic biology of seeds and their establishment allows us to optimize our seed-based restoration practices," says Kendrick. "Working with JJ and the team at VIMS--using their deep understanding of the world the seed experiences--has resulted in a truly interdisciplinary outcome that combines the skills of seagrass and restoration biologists, plant anatomists, and hydrodynamic modelers."

A serendipitous seed story

Winged seeds are commonly used by land plants for dispersal by wind, with the helicopter-like seeds of maple and ash trees a familiar example. So when Orth first noted the wing-like structure on Posidonia seeds during Australian fieldwork in the mid-1990s, his initial thought was that it served a similar function.

"My preliminary hypothesis was that [the wing] would serve to move the seed farther away from the parent plant when it was released from the fruit," says Orth. Posidonia produces large buoyant fruits that break off from the adult plant and can float kilometers away, releasing seeds as they mature.

But years of painstaking research showed the opposite. "When released from the fruit," says Orth, "the seeds drop really fast."

Based on that finding, Orth and colleagues developed a second working hypothesis, that the purpose of the wing was to get the seed to the bottom quickly, before it could be eaten by predators. But field research again proved them wrong. "It turns out not many creatures like to eat these seeds, except for crabs and other small crustaceans," says Orth.

The third time's the charm

The researchers' path to discovering the wing's true function began when Dr. Marion Cambridge of UWA's Oceans Institute suggested a third hypothesis--that the wing keeps the seed at the sediment surface until it can grow anchoring roots.

To test this hypothesis, the team carefully measured the surface area of the seeds using both scanning electron microscopy and X-ray tomography, gauged the flow of currents around seeds placed in a flume, and used these data to build a computer model of the relevant hydrodynamic forces.

"When we brought in Andrew [Pomeroy], a hydrodynamics expert, he got pretty excited about what he saw," says Orth. "He launched the modeling effort that's highlighted in the paper. Together with our microscopy and flume data, it clearly supports the idea that the wing helps the seed maintain its position on the bottom, very similar to how flatfishes can stay on the bottom in strong currents."

In sum, rather than helping to lift and disperse the seeds as with maples, the team's research shows that evolution has engineered the Posidonia wing to push the seed against the seafloor, like the downforce generated by the wing on the rear of a race car.

Stronger currents, larger wings

Further support for the team's hypothesis comes from their comparison of wing width in the seeds of Australia's three Posidonia species, which inhabit a gradient of coastal habitats from current-scoured open shorelines to more sheltered bays.

"The neatest thing about the project," says Orth, "is that the width of the wing differs in the three species that dominate the west coast of Australia, and correlates with each species' environment. Posidonia coriacea, which lives in the most wave-swept areas, has the widest wing, while the other two species --australis and sinuosa--live under calmer conditions and have smaller wings." This correlation extends all the way to the quiet waters of the Mediterranean, where a relict population of the same genus (P. oceanica) has seeds with barely any wing at all.

The findings have important implications for seagrass restoration. "Our modeling work and experiments will better inform Australian resource managers on where to place seeds of these different species," says Orth. "Hopefully armed with this information we can increase the low success rate we observed from one of our recent large-scale restoration efforts in Cockburn Sound."

The findings have also further piqued Orth's interest in traits exhibited by the eelgrass seeds that have long been at the heart of his team's restoration efforts in Virginia's seaside bays. Orth and colleagues first began sowing the bays' shallow waters with eelgrass seeds in 1999. Barren at the time, they today hold more than 7,000 acres of lush eelgrass meadow, making them the largest example of seagrass restoration in the world. In fact, they now hold 75% of the world's restored seagrass acreage.

"We've conducted a lot of experiments with our eelgrass seeds," says Orth, "but still know relatively little about the function of the ribs on these seeds and whether their barrel shape might play some role in keeping them from rolling along the bottom. Our work with Posidonia has added new intrigue to this work."