Culture

In a study published in the scientific journal Nature, researchers at the RIKEN Center for Brain Science (CBS) in Japan report that a part of the mouse brain called the SuM is specialized for detecting new experiences. Within the SuM, responses to experiences related to unknown individuals--called social novelty--were segregated from those related to unfamiliar places--called context novelty--before being sent to distinct parts of the brain's main memory-formation center. This discovery can help us understand normal memory, as well as conditions in which recognizing and reacting to new information is impaired.

Meeting someone for the first time or entering an unfamiliar apartment is a much different experience than meeting an acquaintance or walking into your own home. Normal social interactions, daily functions, and even survival can depend on being able to make the distinction between the unknown and the familiar. Almost all animals seem to be born with this ability, and like other innate behaviors, the team at RIKEN CBS hypothesized that a region of the brain called the hypothalamus might be involved.

To test this hypothesis, they exposed mice to two types of novelty: contextual or social. The novel context was an unfamiliar cage with a few landmark objects and the social novelty was an unfamiliar juvenile mouse. They found that overall brain activity in a part of the hypothalamus called the SuM was much higher in these novel situations than when mice were placed in familiar cages or near familiar mice. "The hypothalamus is a very highly conserved region of the brain across evolution, mostly thought to be involved in innate behaviors like feeding, mating, parenting, and fighting," says Team Leader Thomas McHugh. "Our data suggest that it could also serve as a link between these survival-type behaviors and higher cognitive function."

Surprisingly, although the SuM signaled novelty overall, the majority of individual brain cells in the SuM only responded to one or the other type of novel situation. This is the first time that anyone has found a social/contextual split within a novelty circuit in the brain. In order to see how far the separation went, the team needed to create a new transgenic mouse line that would allow them to see exactly where these SuM neurons project and what they do.

A series of experiments showed that the neurons in the SuM connect with two parts of the hippocampus, the part of the brain known for being involved in memory formation and storage. Neurons that were selective for contextual novelty connected to the DG part of the hippocampus, while those that signaled social novelty were connected to the CA2 region.

Scientists often use novelty tests to assess memory. Mice explore new places and approach unfamiliar mice, making these behaviors both signs of novelty, and by inference, a lack of memory.

McHugh and his team used optogenetic light stimulation to show that output from the SuM directly affected social and contextual memory. For example, exciting the SuM-to-CA2 connection with blue light caused mice to behave as if they had a selective deficit in social memory; they frequently approached familiar mice as if they had never seen them before, but did not explore familiar rooms more than control mice. Likewise, they saw the reverse behavioral pattern when the SuM-to-DG connection was excited.

Accurately detecting contextual and social novelty allows us to adapt our behavior appropriately to changes in daily life. "Understanding how we recognize and react to novel information is fundamental to understanding memory," says McHugh. "Not only does novelty strengthen memory, both in mice and humans, impairment in recognizing and reacting to new information often accompanies psychiatric conditions. This research can thus provide a biological target to examine in such cases."

In a clinical trial testing whether a daily regimen of hydroxychloroquine could protect those most likely to be exposed to COVID-19, researchers from the Perelman School of Medicine at the University of Pennsylvania found there was no difference in infection rates among health care workers who took the drug versus those taking a placebo. While the researchers observed a lack of effect associated with hydroxychloroquine, infection levels were low among the participants, which the researchers believe points to the effectiveness of other prevention measures in the health system: social distancing, use of personal protective equipment, and proper hand hygiene. The study was published today in JAMA Internal Medicine.

"This work represents the first randomized trial of hydroxychloroquine's prophylactic effect for those not yet exposed to COVID-19," said the study's lead author, Benjamin Abella, MD, MPhil, a professor of Emergency Medicine and the director of Penn Medicine's Center for Resuscitation Science. "And while hydroxychloroquine is an effective drug for the treatment of diseases like lupus and malaria, we saw no differences that would lead us to recommend prescribing it as a preventive medication for COVID-19 in front line workers."

Due to the novel nature of COVID-19, the science and medical communities have had to rapidly assess treatment and prevention measures. One drug that has been considered as a potential preventive solution was hydroxychloroquine, based on laboratory studies that it could prevent SARS-CoV-2, the virus that causes COVID-19, from entering cells in tissue culture.

As such, Abella, along with the study's senior author Ravi Amaravadi, MD, an associate professor of Medicine in Hematology-Oncology and the program co-Leader of Cancer Therapeutics at the Abramson Cancer Center, and their co-authors set out to rigorously test whether taking a substantial dose of hydroxychloroquine - 600 milligrams daily for two months- would have an effect on infection rates. They conducted this study among hospital workers that regularly came into contact with COVID-19 patients.

The researchers were able to analyze a pool of 125 physicians, nurses, certified nursing assistants, emergency technicians, and respiratory therapists that they recruited for the study. This population worked in several different areas of the two University hospitals, including the emergency departments and COVID-19 units. Roughly half of the participants in the study took hydroxychloroquine while the other half took a matching placebo (a cellulose pill). The study was double-blinded, meaning neither the researchers, nor the participants knew which drug they were assigned.

Extensive testing was used to rigorously prove who did or did not contract the virus. Each person received swab and antibody testing for COVID-19 at the start of their participation in the study, halfway through, and at the end--an eight-week span during the study period that began April 9 and ended July 14, 2020. Participants also had electrocardiogram (ECG) tests because of concerns about hydroxychloroquine causing heart rhythm problems in severe cases of COVID-19.

"To really test the potential of HCQ as a prevention drug, we felt it was key to recruit health care workers with many hours of direct physical exposure to COVID-19 patients, then randomize them in a double-blind manner between hydroxychloroquine or a matching placebo, and treat them for a long period of time," said Amaravadi. "Through that whole time, we monitored participants closely for their safety."

At the end of the study, 6.3 percent of those who took the hydroxychloroquine had tested positive for COVID-19 while 6.6 percent of those who took the placebos were positive. None required hospitalization. Additionally, there was no difference detected in the heart rhythms between those in either arm of the study, which showed that while the drug had no preventive effect, it was also not detrimental, outside of some temporary side effects like diarrhea for some.

"The differences we saw were negligible," Amaravadi said. "And those who did get the virus, whether they were taking hydroxychloroquine or not, were all asymptomatic or had very mild forms of COVID-19."

While the study was originally slated to recruit 200 health care workers, an analysis along the way showed that a continuation of enrollment would not yield different results. An independent data safety and monitoring board reviewed the findings and concurred.

These results will have an impact on the dozens of planned and ongoing clinical trials around the world that are testing hydroxychloroquine as a prevention for COVID-19 infection in health care workers. While a much larger study could potentially find a different result, the results of the Penn study suggest other forms of prevention, including vaccines, may be worth more attention.

What The Study Did: This single-center study of 77 patients describes the outcomes of patients with symptomatic severe aortic stenosis during the COVID-19 pandemic.

Authors: Stamatios Lerakis, M.D., Ph.D., of the Icahn School of Medicine at Mount Sinai in New York is the corresponding author.

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

(doi:10.1001/jamanetworkopen.2020.19801)

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

Physicists at Aalto University and VTT Technical Research Centre of Finland have developed a new detector for measuring energy quanta at unprecedented resolution. This discovery could help bring quantum computing out of the laboratory and into real-world applications. The results have been published today in Nature.

The type of detector the team works on is called a bolometer, which measures the energy of incoming radiation by measuring how much it heats up the detector. Professor Mikko Möttönen's Quantum Computing and Devices group at Aalto has been developing their expertise in bolometers for quantum computing over the past decade, and have now developed a device that can match current state-of-the-art detectors used in quantum computers.

'It is amazing how we have been able to improve the specs of our bolometer year after year, and now we embark on an exciting journey into the world of quantum devices,' says Möttönen.

Measuring the energy of qubits is at the heart of how quantum computers operate. Most quantum computers currently measure a qubit's energy state by measuring the voltage induced by the qubit. However, there are three problems with voltage measurements: firstly, measuring the voltage requires extensive amplification circuitry, which may limit the scalability of the quantum computer; secondly, this circuitry consumes a lot of power; and thirdly, the voltage measurements carry quantum noise which introduces errors in the qubit readout. Quantum computer researchers hope that by using bolometers to measure qubit energy, they can overcome all of these complications, and now Professor Möttönen's team have developed one that is fast enough and sensitive enough for the job.

'Bolometers are now entering the field of quantum technology and perhaps their first application could be in reading out the quantum information from qubits. The bolometer speed and accuracy seems now right for it,' says Professor Möttönen.

The team had previously produced a bolometer made of a gold-palladium alloy with unparalleled low noise levels in its measurements, but it was still too slow to measure qubits in quantum computers. The breakthrough in this new work was achieved by swapping from making the bolometer out of gold-palladium alloys to making them out of graphene. To do this, they collaborated with Professor Pertti Hakonen's NANO group - also at Aalto University - who have expertise in fabricating graphene-based devices. Graphene has a very low heat capacity, which means that it is possible to detect very small changes in its energy quickly. It is this speed in detecting the energy differences that makes it perfect for a bolometer with applications in measuring qubits and other experimental quantum systems. By swapping to graphene, the researchers have produced a bolometer that can make measurements in well below a microsecond, as fast as the technology currently used to measure qubits.

'Changing to graphene increased the detector speed by 100 times, while the noise level remained the same. After these initial results, there is still a lot of optimisation we can do to make the device even better,' says Professor Hakonen.

Now that the new bolometers can compete when it comes to speed, the hope is to utilise the other advantages bolometers have in quantum technology. While the bolometers reported in the current work performs on par with the current state-of-the-art voltage measurements, future bolometers have the potential to outperform them. Current technology is limited by Heisenberg's uncertainty principle: voltage measurements will always have quantum noise, but bolometers do not. This higher theoretical accuracy, combined with the lower energy demands and smaller size - the graphene flake could fit comfortably inside a single bacterium - means that bolometers are an exciting new device concept for quantum computing.

The next steps for their research is to resolve the smallest energy packets ever observed using bolometers in real-time and to use the bolometer to measure the quantum properties of microwave photons, which not only have exciting applications in quantum technologies such as computing and communications, but also in fundamental understanding of quantum physics.

Many of the scientists involved in the researchers also work at IQM, a spin-out of Aalto University developing technology for quantum computers. “IQM is constantly looking for new ways to enhance its quantum-computer technology and this new bolometer certainly fits the bill,” explains Dr Kuan Yen Tan, Co-Founder of IQM who was also involved in the research.

The immune system is equipped with numerous cell types that effectively fight the various pathogens, humans can encounter during their lives. T cells, for example, have a receptor through which they can specifically recognize and bind antigens. However, in recent decades, cell types with similar protective properties have been discovered that do not possess a specific antigen receptor.

Only a few years ago, scientists identified a group of lymphocytes, so-called "innate lymphoid cells" (ILCs), which are now among the most important players in the body's immune defense and make a significant contribution to the fight against pathogens. Unlike T cells, ILCs do not patrol the bloodstream but are predominantly tissue-resident cells. ILCs reside in various tissues where they interact with many immune and non-immune cell types and contribute to immune surveillance, activation of inflammatory responses, tissue homeostasis and repair and barrier functions. They are found in the bone marrow, secondary lymphoid organs such as lymph nodes and, most prominently, in non-lymphoid tissues with mucosal barriers such as the lung or the small intestine.

The ambivalent role of ILC2 in immune defense

The size of the ILC population and the subset composition varies between organs and can undergo dynamic changes during immune challenge. Type II ILCs (ILC2s) are the dominant subtype in the lung and have been shown to play a major role in immune defense against parasitic worm infection or in wound healing. On the other hand, ILC2s also contribute to the pathology of allergic respiratory inflammation such as asthma.

As in other tissues, ILC2s in the lung expand and differentiate during the first weeks of life after which a fraction persists as tissue-resident cells during adulthood. However, ILC2s can be generated and recruited from other tissues also during adult life in normal physiology and inflammatory conditions. It was unclear whether these ILC2s have specialized functions or whether they were recruited to replenish the local pool of resident cells.

Single-cell atlas of lung innate lymphoid cells

To shed light on these unknown mechanisms, scientists at the Max Planck Institute of Immunobiology and Epigenetics in Freiburg, headed by Dominic Grün, and colleagues from the Würzburg Institute of Systems Immunology led by Georg Gasteiger teamed up with researchers from New York and Marseille to generate a comprehensive single-cell atlas of mouse ILC populations in the bone marrow, neonatal and adult lung during normal physiological condition and during worm infection.

They discovered a pool of local progenitors which receives influx from the bone marrow and has the potential to generate the full spectrum of mature ILC2s observed in the lung during worm infection.

Cell plasticity in response to changing tissues

"Our work sheds light on how the local population of ILC2s in the lung is maintained. We found that progenitors recruited to the lung from other tissues via the bloodstream adjust to the lung environment by modulating their gene expression and differentiate into mature ILC2s that are almost indistinguishable from their counterparts derived from lung-resident progenitors. This is an exciting example for the plasticity of immune cell states in response to changing tissue environments", says Dominic Grün, Max Planck group leader and member of the CIBSS - Centre for Integrative Biological Signalling Studies, Cluster of Excellence at the University of Freiburg.

The study published in the scientific journal "Immunity" describes a "continuum" of ILC2 differentiation stages connecting the progenitors with the mature populations, including previously unknown ILC2 subtypes.

"We were able to reveal the complexity of the functions of ILC2s in an unprecedented manner and at the same time draw conclusions about their origin and development," explains Patrice Zeis, first author of the study. To detect the heterogeneity and development of lung ILC2s in a comparable systemic way, the scientists combined single-cell RNA sequencing with machine learning approaches. Thus, they successfully created "molecular fingerprints" for thousands of innate immune cells in the murine lung, and derived novel insights on the cell's identity, functions and the developmental relationships between the cells in the model organism.

Our proposed concepts of tissue differentiation and adaption of ILC2s may help to understand how local differentiation of ILCs can contribute to inflammatory diseases and might be applicable to other immune cell types", explains Patrice Zeis.

The causes of cerebral palsy have long been debated and often are attributed to in utero infections, premature birth, or brain injury to the baby near or during delivery, usually from a lack of oxygen. But many young children diagnosed with cerebral palsy have not experienced such events.

Now, scientists have identified mutations in single genes that can be responsible for at least some cases of cerebral palsy, according to a new study led by researchers at Washington University School of Medicine in St. Louis, the University of Arizona College of Medicine in Phoenix, and Yale University. The study indicates that many of the mutations occur randomly and are not inherited from a child's parents. The research is part of the International Cerebral Palsy Genomics Consortium, a global effort to understand genetic causes of cerebral palsy. The new knowledge could help improve the diagnosis of cerebral palsy and lead to future therapies.

The study appears Sept. 28 in the journal Nature Genetics.

The scientists were able to show that introducing mutations of the same genes into fruit flies caused the insects to have movement difficulties that resemble those common in people with cerebral palsy, a common neurodevelopmental disorder. Cerebral palsy can affect gait, balance and posture. It does not worsen over time but varies widely in severity, with some patients able to walk unaided, while others may use walkers or wheelchairs. According to the Centers for Disease Control and Prevention, it affects about two to four children per 1,000 globally.

"This international collaboration allowed us to conduct the largest genetic analysis of cerebral palsy patients and their parents to date," said Sheng Chih (Peter) Jin, PhD, an assistant professor of genetics at Washington University. "What is exciting about uncovering new genetic causes of cerebral palsy is the potential for the future development of therapies for these patients."

Researchers have suspected that genetics could contribute to an elevated risk of developing cerebral palsy, but until now, individual gene mutations that can cause the disorder had rarely been identified. To better understand genetic contributions to cerebral palsy, the scientists sequenced the entire protein-coding portion of the genomes from 250 participants -- cerebral palsy patients and both parents -- seeking mutations that could play causal roles in cerebral palsy.

In particular, the analysis identified two genes -- FBXO31 and RHOB -- that when mutated are each alone sufficient to cause cerebral palsy. Many of the additional genes carrying mutations were only present in the child with cerebral palsy -- meaning they arose randomly -- while others were inherited from both parents. In general, the researchers found that many of the genes implicated in cerebral palsy have important roles in the wiring of brain circuitry during early stages of development.

"When these mutations were introduced into fruit flies, they recapitulated what we see in human patients," said senior author Michael Kruer, MD, of the University of Arizona College of Medicine in Phoenix. "In a nutshell, the flies couldn't walk. The movement of the flies was greatly diminished, and this was examined in several different ways. We were able to validate that these genes -- nearly two dozen of them were tested in the flies -- play an important role in neuromotor function and in the biology of cerebral palsy."

The researchers also noted that some of the genes newly implicated in cerebral palsy have in past research been associated with autism, intellectual disability and epilepsy.

"For some individuals with cerebral palsy, they only have difficulty with movement and have no other disabilities whatsoever," Kruer said. "But we also see huge overlap among neurodevelopmental disorders. For example, more than half of cerebral palsy patients have some type of learning or intellectual disability. About 40% have epilepsy, and 6% to 8% have autism. So, what we see in the genetics of our new study is reflected in what we have seen in our patients for many years."

In about 12% of the cerebral palsy patients in the study, the causal genetic mutations were acquired by chance, not inherited from either parent. In about 2% of the patients in the study, the mutations were inherited from both parents, neither of whom had cerebral palsy. The remaining 86% of cases could have environmental causes, or contributions from other genetic variations that will require a larger study to reveal, or a combination of genetic mutations and environmental interactions that the researchers are still working to understand.

"We hope this study can help give peace of mind to parents who may have been told over the years that there must have been some kind of problem during the pregnancy or delivery to cause their child to have cerebral palsy," Kruer said. "Our study has implications for genetic counseling for parents who have a child with cerebral palsy, in helping determine the chances of a second child being similarly affected."

Added Jin: "We are continuing to study cerebral palsy patients and their parents, and as our sample size increases, we may begin to be able to measure the contributions from less common recessive and dominant mutations passed down from one or both parents. This study provides clues to where we can begin to design treatments. Our genetic understanding of cerebral palsy is still in its earliest phase -- we've just scratched the surface with this study. We look forward to continuing this research to better understand what causes cerebral palsy so we can find ways to prevent or treat it."

Since first appearing in late 2019, the novel virus, SARS-CoV-2, has had a range of impacts on those it infects. Some people become severely ill with COVID-19, the disease caused by the virus, and require hospitalization, whereas others have mild symptoms or are even asymptomatic.

There are several factors that influence a person's susceptibility to having a severe reaction, such as their age and the existence of other medical conditions. But one's genetics also plays a role, and, over the last few months, research by the COVID-19 Host Genetics Initiative has shown that genetic variants in one region on chromosome 3 impose a larger risk that their carriers will develop a severe form of the disease.

Now, a new study, published in Nature, has revealed that this genetic region is almost identical to that of a 50,000-year old Neanderthal from southern Europe. Further analysis has shown that, through interbreeding, the variants came over to the ancestors of modern humans about 60,000 years ago.

"It is striking that the genetic heritage from Neanderthals has such tragic consequences during the current pandemic," said Professor Svante Pääbo, who leads the Human Evolutionary Genomics Unit at the Okinawa Institute of Science and Technology Graduate University (OIST).

Is severe COVID-19 written in our genes?

Chromosomes are tiny structures that are found in the nucleus of cells and carry an organism's genetic material. They come in pairs with one chromosome in each pair inherited from each parent. Humans have 23 of these pairs. Thus, 46 chromosomes carry the entirety of our DNA - millions upon millions of base pairs. And although the vast majority are the same between people, mutations do occur, and variations persist, at the DNA level.

The research by the COVID-19 Host Genetics Initiative looked at over 3,000 people including both people who were hospitalized with severe COVID-19 and people who were infected by the virus but weren't hospitalized. It identified a region on chromosome 3 that influences whether a person infected with the virus will become severely ill and needs to be hospitalized.

The identified genetic region is very long, spanning 49.4 thousand base pairs, and the variants that impose a higher risk to severe COVID-19 are strongly linked - if a person has one of the variants then they're very likely to have all thirteen of them. Variants like these have previously been found to come from Neanderthals or Denisovans so Professor Pääbo, in collaboration with Professor Hugo Zeberg, first author of the paper and a researcher at the Max Planck Institute for Evolutionary Anthropology and Karolinska Institutet, decided to investigate whether this was the case.

They found that a Neanderthal from southern Europe carried an almost identical genetic region whereas two Neanderthals from southern Siberia and a Denisovan did not.

Next, they questioned whether the variants had come over from Neanderthals or had been inherited by both Neanderthals and present-day people through a common ancestor.

If the variants had come from interbreeding between the two groups of people, then this would have occurred as recently as 50,000 years ago. Whereas, if the variants had come from the last common ancestor, they would have been around in modern humans for about 550,000 years. But random genetic mutations, and recombination between chromosomes, would have also occurred during this time and because the variants between the Neanderthal from southern Europe and present-day people are so similar over such a long stretch of DNA, the researchers showed that it was much more likely that they came from interbreeding.

Professor Pääbo and Professor Zeberg concluded that Neanderthals related to the one from southern Europe contributed this DNA region to present-day people around 60,000 years ago when the two groups met.

Neanderthal variants pose up to three times the risk

Professor Zeberg explained that those who carry these Neanderthal variants have up to three times the risk of requiring mechanical ventilation. "Obviously, factors such as your age and other diseases you may have also affect how severely you are affected by the virus. But among genetic factors, this is the strongest one."

The researchers also found that there are major differences in how common these variants are in different parts of the world. In South Asia about 50% of the population carry them. However, in East Asia they're almost absent.

It is not yet known why the Neanderthal gene region is associated with increased risk of becoming severely ill. "This is something that we and others are now investigating as quickly as possible," said Professor Pääbo.

Intelligent algorithms are used to create paintings, write poems, and compose music. According to a study by an international team of researchers from the Massachusetts Institute of Technology (MIT), and the Center of Humans and Machines at the Max Planck Institute for Human Development, whether people perceive artificial intelligence (AI) as the ingenious creator of art or simply another tool used by artists depends on how information about AI art is presented. The results were published in the journal iScience.

In October 2018, a work of art by Edmond de Belamie, which was created with the help of an intelligent algorithm, was auctioned for 432,500 USD at Christie's Auction House. According to Christie's auction advertisement, the portrait was created by artificial intelligence (AI). The media often described this as the first work of art not created by a human but rather autonomously by a machine. The proceeds were not given to the machine but instead to the French artists' collective Obvious. This collective had fed an algorithm with pictures of real paintings by human painters and trained it to create images autonomously. They then selected a certain picture, printed it, gave it a name, and marketed it. However, the programmers who developed the artificial neural networks and algorithms used were not mentioned, nor did they receive any of the proceeds from the sale of the painting.

"Many people are involved in AI art: artists, curators and programmers alike. At the same time, there is a tendency - especially in the media - to endow AI with humanlike characteristics. According to the reports you read, creative AI autonomously creates ingenious works of art. We wanted to know whether there is a connection between this humanization of AI and the question of who gets credit for AI art", Ziv Epstein, PhD student at the MIT Media Lab and first author of the study, explained.

To this end, the researchers informed almost 600 participants about how AI art is created and asked who should receive recognition for the work of art. At the same time, they determined the extent to which each participant humanizes AIs. The individual answers varied greatly. But on average, people who humanized AI and did not perceive it merely as a tool also felt that AI should receive recognition for the AI art and not the people involved in the creation process.

When asked which people deserve the most recognition in the process of creating AI art, recognition was initially given to the artists who provided the learning algorithms with data and trained them. Only then were curators named, followed by technicians who programmed the algorithms. And finally, the "crowd" (i.e. the mass of Internet users who produce the data material with which AIs are often trained) was mentioned. Respondents who humanized the AI gave more recognition to the technicians and the crowd, but proportionally less to the artists. A similar picture emerges when respondents are asked about who is responsible, for example when an AI artwork violates copyright. Here, too, the ones who humanized the AIs placed more responsibility on the AIs.

A key finding of the study is that it is possible to actively manipulate whether people humanize AIs by changing the language used to report on AI systems in art. The creative process can be described by explaining the fact that AI, supported only by an artistic collaborator, conceives and creates new works of art. Alternatively, the process can be described by explaining the fact that an artist conceives the artwork and that the AI executes simple commands given by the artist. The different descriptions changed the degree of humanization and thus also to whom the participants attributed recognition and responsibility for AI art from among the human actors.

"Because AI is increasingly penetrating our society, we will have to pay more attention to who is responsible for what is created with AI. In the end, there are humans behind every AI. This is particularly relevant when the AI malfunctions and causes damage - for example, in an accident involving an autonomous vehicle. It is therefore important to understand that language influences our view of AI and that a humanization of AI leads to problems in assigning responsibility", says Iyad Rahwan, director of the Center for Humans and Machine at the Max Planck Institute for Human Development and co-author of the study.

SAN FRANCISCO, CA--September 29, 2020--The latent reservoir is the last bastion of HIV's resistance to a cure. But it is difficult to destroy because it is invisible: the cells in the reservoir harbor virus that is dormant, so they don't have any viral proteins on their surface that would give them away.

As a result, scientists have struggled to learn what the reservoir looks like in individuals with HIV. And without this knowledge, they harbor little hope of being able to target the reservoir with therapies that could eliminate or reduce it, thus ridding people of HIV infection for good.

To fish out reservoir cells, scientists have to reawaken the virus by activating cells they collect from infected individuals. Once awake, the virus produces proteins that mark the surface of its host cells, which gives researchers a handle to find and study these cells. However, the very process of reactivating the virus leads to changes to the cells' biology that obscure their original identity. And so, the true identity of the cells making up the latent reservoir--also called latent cells--has remained elusive.

To overcome this problem, Gladstone Scientist Nadia Roan, PhD, has taken advantage of an approach she developed previously to backtrack reactivated reservoir cells to their original latent state. With this approach, Roan and her team have mapped out an atlas of the reservoir cells of eight individuals living with HIV, which they recently reported in the journal eLIFE.

"Our findings challenge some previously held assumptions about the makeup of the reservoir," says Roan, who is also an associate professor of urology at UC San Francisco. "In addition, our detailed map of reservoir cells will make it easier to find these cells in infected individuals, which will fundamentally change how the latent reservoir can be studied."

Method to the Madness

Previous investigations suggest that the reservoir consists in large part of memory T cells, a subset of cells in the immune system that retain the memory of past infections. These cells can remain for a long time in the body in a quiescent state, waiting for a new infection by a previously encountered virus to wake them up. That makes them the perfect hiding place for HIV.

But memory T cells come in many types, and a commonly held view among scientists is that the latent reservoir consists of a random assortment of memory T cells rather than a specific subset.

"If so, targeting latently infected cells as a curative strategy would be all the more difficult," says Roan.

Most previous studies of the reservoir have relied on the examination of only a few proteins on the surface of cells. With Roan's approach, however, her team can follow nearly 40 proteins at once, which greatly increases their ability to distinguish even closely related cells. The researchers can also compare populations of cells before and after reactivation, thus matching each reactivated cell to the pre-activation cell that resembles it most, as if going back in time.

"It's somewhat like implementing facial recognition technology on cells," says Roan. "You can think of it as having a photo of someone in their fifties, and trying to identify them in their high school yearbook. Although individuals' looks change as they age, you can typically still recognize them by looking for a combination of their traits. Similarly, latent cells change as they are reactivated, but they still retain some of their original identity in a way that we can capture by tracking 40 proteins at once."

Roan's team carried out this analysis on millions of cells collected from eight individuals under antiretroviral therapy. The cells came from the donors' blood and gut, the latter which is thought to be a primary site of viral persistence in individuals on this treatment. The scientists also obtained cells from the lymph nodes of one donor.

"Reservoir cells reside in the blood but also in various tissues in the body," says Jason Neidleman, a senior research associate in Roan's lab and co-first author of the study. "We wanted to know how reservoir cells in the blood compare to those from other sites."

The team first built an atlas of the CD4+ T cells (the type of T cells HIV can infect) in each infected donor, based on the assortment of the 40 proteins these cells contained. Then, they mapped each reactivated cell from each individual against the corresponding atlas to find the most similar atlas cell. This most similar cell is thought to represent the original state of the latently infected cell, before it reawakened from latency.

"Somewhat to our surprise, we found that the blood reservoir is not randomly distributed among memory T cells," says Xiaoyu Luo, PhD, a scientist at Gladstone and co-first author of the study. "Instead, reservoir cells in the blood samples map to a few distinct areas on the atlas. What's more, reservoir cells from different donors mapped near one another, indicate that they share common features."

When comparing the blood, lymph nodes, and gut samples, the team also revealed important differences between blood and tissue cells, but also some shared markers, in particular between gut and lymph node cells.

"The existence of shared features across people and tissue types give us hope that we can one day design therapies that target large fractions of the reservoir at once and will work for many infected individuals," says Roan.

Toward a Deeper Understanding of the Reservoir

For now, the team is keen to use their findings to learn more about the reservoir.

"One of the problems that has galled the field is that most reservoir cells harbor defective versions of the HIV genome," says Roan. "These cells do not constitute the most clinically relevant reservoir of HIV, because even after they are reactivated, they do not produce infectious virus."

This situation makes it difficult to home in on the reservoir cells that truly matter--those with a viral genome competent for replication and infection--which can represent as little as 1 percent of the reservoir population.

However, Roan and her team found that when they used the shared markers they identified to extract cells from donor samples, they could obtain populations of cells where more than 50 percent of the reservoir cells contained intact viral genomes.

"These results suggest that intact and defective virus are kept in different subsets of cells," says Roan. "And now that we can more readily identify the reservoir cells capable of producing infectious virus, we can begin to elucidate how these cells persist in an infected individual over time."

Another problem of infectious reservoir cells is that they are very rare to begin with--perhaps as few as one in a million CD4 T cells--which makes it all the more difficult to obtain enough replication-competent reservoir cells to carry out experiments. The markers Roan's team identified alleviate this problem by allowing researchers to increase the proportion of infectious reservoir cells in a donor's sample by 100-fold or more.

"By increasing our access to infectious reservoir cells this much, we open up the possibility of conducting a variety of previously impossible experiments that could greatly refine our understanding of reservoir cells," says Roan. "In particular, it might allow for the discovery of unanticipated--and perhaps even unique--markers of latent cells, which could speed up the design of new therapies for HIV eradication."

A group of marine biologists is pushing for more international collaboration to manage the Humboldt squid population after their study to identify its genetic stocks revealed its vulnerability to overfishing by fleets trying to feed the world’s hunger for squids.

Hiroshima University marine biologist Gustavo Sanchez led a team of researchers to find out the genetic structure of the Humboldt squid population in the Eastern Pacific Ocean using two types of DNA markers — the mitochondrial ND2 gene and nuclear microsatellite loci.

The team found that Humboldt squids could trace back their population to three historical matrilineage that spread out during the late Pleistocene and that the species has at least two contemporary genetic stocks homogeneously co-distributed in the northern and southern hemispheres.

Different genetic stocks within a species are usually defined by where they feed and breed. But in Humboldt squids, DNA markers showed no north-south divide. The equator doesn’t serve as a natural barrier to separate the different genetic stocks of these fast swimmers risking capture by different fishery fleets along their migration route.

“In our study, we identify at least two genetic stocks co-distributed in the north and southern hemisphere of the Eastern Pacific Ocean. Our results suggest that rather than independent marine policies from each country, the sustainability of this squid requires an international marine policy,” Sanchez said.

To ensure sustainable fishing, countries in South America where the squid is traditionally found have established yearly catch quotas. But the study found this approach to be ineffective, especially as catch restrictions are absent in international waters on the squid’s migration path.

“Countries fishing this squid have established catch quotas with no consideration that the total amount varies from year to year, and that the amount of squid caught influences the number of squids next year. By doing so, the genetic contribution of the offspring every year will also clearly fluctuate. In such a situation, there is a risk of having a genetic erosion with a smaller number of squids which are also less likely to adapt rapidly to the changing environment,” he remarked.

“From our study, it is also clear that the squids caught by different countries also belong at least two different populations, with likely different genetic contribution for the next generation. Catching these squids without knowing that their genetic contribution is different, is also very risky.”

A grim warning

Both warm tropical waters and the cooler Humboldt current, which runs from Tierra del Fuego at the southernmost tip of the South American mainland upwards to the northern coast of Peru, play a role in the Humboldt squid’s life cycle.

The squid seeks warm waters near the equator to spawn its clusters of neutrally buoyant eggs. But it needs nutrient-rich cool waters where they go on a feeding frenzy to grow from one-millimeter paralarvae specks to enormous predators of over 1.2 meters long.

These squids typically spawn only once during their one-year lifespan then die, making their future volatile if fishing goes unchecked. And such fears are not farfetched. 

It’s eastern relatives, the Japanese flying squid, has suffered the same fate. Years of overfishing, poor regulatory oversight, and the changing climate have depleted their population at an alarming rate that yearly catch of Japanese fishermen dropped over 70% from more than 200,000 tons in 2011 to 53,000 tons in 2017. The shortage worries the fishing town of Hakodate whose identity and economy are intertwined with the squid.

“The population of the Japanese flying squids has decreased, and this is because along the distribution of this squid you have a lot of fleets from Japan, China, Korea, and Taiwan, some with high capacity for catching this squid. Countries like China with massive distant-water fishing fleets can move anywhere outside their national jurisdiction to catch this squid. If you have the technology you can go to international waters and catch anything,” Sanchez said.

He said Hakodate’s experience could be a grim warning of things to come for his country Peru.

“The Humboldt squid is the second most important economical species in Peru. That means that when we have less squid, that will affect also the economy of the country, particularly the economy of the fisherman that depends on this squid,” he said.

Historical clues

Over 90 percent of warming on Earth in the past 50 years has happened in the ocean and the speed it is heating up is accelerating. Warming oceans due to climate change have driven sea creatures toward the poles. 

The Humboldt squid population itself has expanded its migratory path. It recently stretched its route farther north to Alaska and south to the tip of Chile which exposes these cephalopods that hunt in packs of up to 1,200 to fishing boats in each territory on its path as well as technologically advanced vessels waiting in international waters.

Sanchez’s team found a similar pattern of historical population expansion under extreme climate conditions when they looked at the mitochondrial DNA of the squid. They found that warming global temperatures 30,000 years ago which thawed Ice Age glaciers contributed to a sea-level rise favorable for the Humboldt squid population to spread out. The event which coincided with the decrease in the population of sperm whales, their natural predators, led to a population expansion for the squids.

Although quick to adapt, warmer temperatures mean less food, smaller maturity size, and fewer eggs to replenish its population. 

Securing Humboldt squids’ future

Much, including its conservation status, is still unknown of this large squid species. But with its economic significance to fishing communities and its important role in the marine ecosystem as food for diverse species, the new knowledge of its genetic stock can help inform future marine policies to manage its population.

“The Humboldt squid is the largest squid fishery in the world and is heavily caught in the Eastern Pacific Ocean by several countries, including countries from Asia like Japan, Korea, China, and Taiwan. This squid is one of the most commercial squids in the world, and it sustains the economy of many countries.”

“Identifying genetic stocks, also known as genetically different groups, throughout population genetics is very important for implementing marine policies that control the total catch of this squid. The high migratory capacity of this squid is the main challenge to identify the exact number of genetic stocks, and more genetic resources and sampling are required to clearly reveal this number.”

Rapeseed has the potential to replace soy as the best plant-based source of protein for humans. In a current study, nutrition scientists at the Martin Luther University Halle-Wittenberg (MLU), found that rapeseed protein consumption has comparable beneficial effects on human metabolism as soy protein. The glucose metabolism and satiety were even better. Another advantage: The proteins can be obtained from the by-products of rapeseed oil production. The study was published in the journal Nutrients.

For a balanced and healthy diet, humans need protein. "It contains essential amino acids which can not be synthesized in the body," says Professor Gabriele Stangl from the Institute of Agricultural and Nutritional Sciences at MLU. Meat and fish are important sources of high-quality proteins. However, certain plants can also provide valuable proteins. "Soy is generally considered the best source of plant protein as it contains a particularly beneficial composition of amino acids," says Stangl.

Her team investigated whether rapeseed, which has a comparably beneficial composition of amino acids, could be an alternative to soy. Rapeseed also contains phytochemicals - chemical compounds produced by plants - which could have beneficial effects on health, says Stangl. "So far, only a few data on the effect of rapeseed protein intake in humans had been available," adds the scientist. In comparison to soy rapeseed has several other advantages: It is already being cultivated in Europe and the protein-rich by-products of the rapeseed oil production could be used as ingredients for new food products. These by-products are currently used exclusively for animal feed.

In a study with 20 participants, the team investigated the effect of ingested rapeseed and soy proteins on human metabolism. Before the interventions the participants were asked to document their diets for a few days. Then they were invited to eat a specifically prepared meal on three separate days: noodles with tomato sauce, that either contained no additional protein, or was enriched with soy or rapeseed protein. After the meal, blood was regularly drawn from the participants over a six-hour period. "By using this study design, we were able to assess the acute metabolic response of each study participants to the dietary treatments." says Stangl.

The study showed: "The rapeseed protein induced comparable effects on metabolic parameters and cardiovascular risk factors as soy protein. Rapeseed even produced a slightly more beneficial insulin response in the body," says nutritionist Christin Volk from MLU. Another benefit was that the participants had a longer feeling of satiety after eating the rapeseed protein. "To conclude, rapeseed appears to be a valuable alternative to soy in the human diet," says Volk.

The only drawback: "Rapeseed protein, in contrast to soy protein, has a mustard flavour," says Volk. Therefore, rapeseed is more suitable for the production of savoury foods rather than sweet foods, explains the researcher.

Scientists from the University of Portsmouth and Royal Botanic Gardens, Kew, have come up with a formula to help plant breeders and farmers around the world grow crops in a more sustainable way.

The new checklist, which has just been published in the Botanical Journal of the Linnean Society, will guide plant breeders to better understand the species they are trying to improve. It will also help them find ways to increase growth and yield of crops using wild plant species from which they were once domesticated.

There is an urgent and critical need for changes in farming techniques due to the growing challenges of global warming faced by crop producers. Plants that were selected and bred to suit certain climates, now need more help from the humans who are damaging the environment in which they grow.

Study author Dr Rocio Perez-Barrales, Senior Lecturer in the School of Biological Science at the University of Portsmouth said: "When the human race first domesticated crops, the climate and environment were completely different - what we are seeing in the last 50 years is a rapid change in climate. The world is now frequently facing catastrophic climate events like droughts and in the UK we are now seeing some crops being harvested up to a month earlier than they used to be.

"When plants were domesticated, they were artificially selected for a specific desirable trait. Artificial selection and farming have led to quality improvements in foods such as meat, milk, and fruit. However, over hundreds of years, there has been a negative impact to this process - a reduction in plant genetic diversity.

"Scientists believe genetic diversity is important for plants to cope with a change in environment. This leads to a choice of using an artificial process such as the use of pesticides, to protect crops against pests. An alternative for plant breeders is to use wild crop relatives and use the natural genetic variation in those species that protects them against the natural enemies.

"Climate change is altering the way crops behave. Crops have lost so much genetic diversity they are less able to adapt and respond to climate change. Scientists are now looking at wild crop relatives to see what traits can be improved to make crops better adapted to the current environmental challenges."

The researchers re-visited guidelines set out 50 years ago that have since become outdated. They used this classification as a basis to deliver a new method of improving crops, without destroying the very few natural environments left in the world to grow food.

Dr Perez-Barrales explained: "Some crops have just a few closely related species, whilst others might have a hundred or so. For example, linseed has more than 150 related species, and the challenge is how do we select the relevant traits and from what wild relatives? In answering this question, we realised that we needed to learn more from the biology of the species, which can only be done by using modern classification developed using the latest science. The classification developed in the early 1970's needed to be updated, and in effect rebooted, to integrate this modern information."

This new toolset for crop breeders relies on identifying which wild crop relative needs to be explored in order to improve the crops. Dr Perez-Barrales said: "There may be a demand to grow linseed, for example, in countries at different latitudes. Linseed (Linum usitatissimum) was domesticated in the Middle East 10,000 years ago, and we can grow it in England because it naturally captured genes from pale blue flax, Linum bienne, allowing the crop to grow in northern and colder environments. My research looks at the natural variation in flowering of wild Linum species to see if we can use it to improve linseed. That way the right genes can be selected and introduced into the crop, something that plant breeders do regularly. These new guidelines will help plant breeders become more sustainable and efficient. We believe it is the future of farming."

This paper recommends guidelines for plant breeders to select the one right species to improve the crops. The guidelines include:

1. To understand the genetic diversity between species (genetic distance) and ascertain how closely related the target species are. This is equivalent to human genealogy, so you are more closely related to siblings than cousins. The closer you are related the better because there will be fewer genetic barriers.

2. To understand if there is genetic compatibility between species. This includes understanding variation in chromosome numbers. For two plant species to successfully cross, they need to have the same number of chromosomes. As with humans, if the number of chromosomes don't match there will be problems in reproduction. However, plants can have very different chromosome numbers, ranging from 14 to more than 100. It is important to understand chromosome variation so we can understand their compatibility.

3. To gather all the information of the pollination biology, reproduction and the mechanisms to avoid inbreeding. Plants can prevent self-pollination and inbreeding, so the pollen of a flower does not fertilise the ovules from the same flower. Just like in animals, inbreeding can cause genetic diseases. But the mechanisms that avoid selfing can create barriers between the crop and the wild relative, making it difficult to create new hybrids that could be tested to validate the newly improved crop

Dr Juan Viruel from Kew Garden said: "In this study we advise plant breeders to use phylogenetic distance metrics, cytogenetic compatibility data (for example, chromosome number and ploidy) and information about the breeding system to shortlist wild species for plant breeding programmes". With this information we can better select the wild species to improve our crops. It is an invaluable checklist for plant breeders and will help production of crops in a more sustainable way."

The best way to communicate with parent smokers about the risks of secondhand smoke to their children is to use videos depicting the risks, as well as solutions to reduce those risks.

Those were the findings of a study, published in the Journal of Health Communication, which demonstrates that video messages, compared to text-only messages, are significantly more effective in influencing parent smokers’ intentions to protect their offspring from exposure to secondhand smoke.

The effects and diseases caused by secondhand smoking kills 41,000 people in America annually (Centers for Disease Control and Prevention, 2017). Of the 58 million Americans exposed to secondhand smoke, infants and children are the most vulnerable to adverse health effects.

In order to assess which format of communication may be most effective to getting people to not only stop smoking, but stop smoking near their children, experts from both the Center of Tobacco Studies at Rutgers University and The SIDS Center of New Jersey, assessed 623 adult daily smokers living with children in the US, aged 0–15

The participants were assigned to view messages that differed by recommendation (stopping altogether – known as cessation vs cessation plus exposure reduction) and format (video vs text-only), or to a no-message control group.

All messages delivered to participants discussed the health risks of secondhand smoke. The cessation messages encouraged smokers to seek information about getting help to quit and for couples to work together to help each other quit, while the “cessation plus exposure reduction” messages additionally discussed strategies for parent smokers to protect their children from secondhand smoke, like smoking outdoors, washing toys, surfaces, and clothes exposed to secondhand smoke, and not smoking in a car with children.

Results showed:

Parent smokers who saw video messages had significantly greater intentions to reduce secondhand smoke exposure to their children, as well as discuss the issue and risks of secondhand smoke with other parents, compared to parent smokers that saw text-only messages.
Parents who saw videos also had significantly greater intentions to quit smoking altogether and get help to quit smoking compared to parents who did not view a message.
Parent smokers who viewed either message recommendation reported greater harm perceptions, perceptions of self-efficacy to protect children from secondhand smoke, and intentions to get help to quit smoking than the no-message control group.
Cessation plus exposure reduction recommendations elicited greater quit intentions than the no-message control.

Reporting on their findings, lead author Dr. Jennah Sontag stated, “All forms of communication tested in this study were effective in influencing perceptions and intentions about the risks of secondhand smoke for children, indicating that even communication that lasts only one to two minutes or is presented in text form may influence parent smokers to reduce or eliminate secondhand smoke exposure to children.

“But our research suggests that sharing this information visually through a video can be especially effective, and these videos should include recommendations for both cessation and ways to protect children from secondhand smoke.

“We already know that visual messages are better than text-only formats of tobacco-related risk communication. However, this study clearly demonstrates that the visual portrayals of the potential health risks of secondhand smoke exposure among infants and children, from asthma, ear infections, respiratory problems or SIDS, may have influenced greater harm perceptions due to the severity of these outcomes.”

It is estimated that two in five children in the US are exposed to secondhand smoking. However, notable disparities exist including those from low-income communities, 3- to 11-year olds, and black children, who are at highest risk of exposure. Several environmental factors play a role in this exposure, including a lack of smokefree laws in public spaces or smokefree rules at home, and living in multiunit housing. US healthcare expenditures of secondhand smoke exposure among children living in public housing were more than $180 million in 2011 alone.

Only 55% of smoking mothers quit smoking during pregnancy, and 70% of these relapse into smoking after childbirth.

Sontag believes these types of videos are more likely to reach wider audiences – due to their shareability– and therefore should be considered for future anti-smoking and secondhand smoking communications.

“Video shows the greatest potential to influence perceptions and intentions related to reducing secondhand smoke exposure. To reach parent smokers, such messaging can be used by practitioners in clinical settings, such as waiting rooms and examination rooms, which allow for follow-up discussions, or in family-based education and community organizations. Because videos are more appropriate for the digital/social media landscape, messages can be further disseminated among parents and other caregivers,” she adds.

The paper calls for future research to assess the extent to which secondhand smoking-related communication that uses videos and includes recommendations for cessation and exposure reduction influences parent smokers to inquire with their doctor about cessation options. “It is also important to assess whether strategies that protect children from secondhand smoke are carried out long term by parent smokers who do not quit,” it states.

Limitations of the study include that over 70% of participants were female. In addition, parent smokers viewed only one message one time on a computer screen in a controlled experimental setting. Messages viewed in a natural environment (e.g., clinics, hospitals) and multiple exposures may produce different results. Additionally, 38% of participants reported that they never smoke inside the home, implying that these participants are already exhibiting one of the exposure-reduction behaviors that reduces secondhand smoke exposure to children; recruitment of only parent smokers that always smoke inside the home may have produced different results.

Further information

For more information, please contact:
Simon Wesson, Press & Media Executive
Email: newsroom@taylorandfrancis.com
Tel.: +44 (0)7817299937
Follow us on Twitter: @tandfnewsroom

This study was funded by the New Jersey Commission on Cancer Research.

About Taylor & Francis Group

Taylor & Francis Group partners with researchers, scholarly societies, universities and libraries worldwide to bring knowledge to life. As one of the world’s leading publishers of scholarly journals, books, ebooks and reference works our content spans all areas of Humanities, Social Sciences, Behavioural Sciences, Science, Technology and Medicine.

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Journal of Health Communication

DOI

10.1080/10810730.2020.1797947

Experts who study animal pheromones have traced the evolutionary origins of genes that allow mice, rats and other rodents to communicate through smell. The discovery is a clear example of how new genes can evolve through the random chance of molecular tinkering and may make identifying new pheromones easier in future studies. The results, representing a genealogy for the exocrine-gland secreting peptide (ESP) gene family, were published by researchers at the University of Tokyo in the journal Molecular Biology and Evolution.

Researchers led by Professor Kazushige Touhara in the University of Tokyo Laboratory of Biological Chemistry previously studied ESP proteins that affect mice's social or sexual behavior when secreted in one mouse's tears or saliva and spread to other animals through social touch.

Recently, Project Associate Professor Yoshihito Niimura led a search for the evolutionary origin of ESP genes using the wide variety of fully sequenced animal genomes available in modern DNA databases. Niimura looked for ESP genes in 100 different mammals and found them only in two evolutionarily closely related families of rodents: the Muridae family of mice, rats and gerbils, and the Cricetidae family of hamsters and voles.

Notably, the Cricetidae had few ESP genes usually all grouped together in the same stretch of DNA, but the Muridae had both that same small group of ESP genes as well as a second, larger group of additional ESP genes.

"We can imagine about 35 million years ago, the common ancestor of Muridae and Cricetidae formed the first ESP genes. Eventually, approximately 30 million years ago, the ancestor of Muridae duplicated and expanded these ESP genes. So now mice have many more ESP genes than the Cricetidae rodents," said Niimura.

To identify the source of what formed the first ESP gene, researchers compared additional genome sequences. They uncovered how random chance copied uniquely functional portions of two other genes, then coincidentally pasted them next to each other.

The DNA sequence of a gene includes portions called exons, which later become the functional protein, and other portions called introns, which do not become protein. Introns and exons are spaced throughout the gene with no apparent organization, introns interrupting essential functional portions of exons. Therefore, if a single exon were randomly copied and pasted elsewhere in the genome, any resulting protein fragment would have no meaningful function.

However, if an exon-only version of a gene were copied and reinserted into the genome, the chances of that new sequence remaining functional become much greater. Cells do create exon-only versions of genes called mRNA as part of the normal process of making protein from genes and cells do possess machinery, likely left over from viral infections, that can copy mRNA back into the DNA strand.

"This is not the normal way of things in cells, but it is a common source of evolution. We guess this is what happened to make ESP genes because the whole functional portion of the ESP gene is one exon, no intron interruption," said Niimura.

Specifically, the research team discovered for the first time that ESP proteins contain an uncommon spiral shape characteristic of alpha-globin, a component of the iron-carrying hemoglobin protein in blood. DNA sequence comparisons revealed that multiple alpha-globin gene exons spliced together show a subtle but distinctive similarity to the ESP gene sequence.

"It doesn't matter that hemoglobin is the source of the ESP pheromone. Any protein can become a pheromone if it is used for species-specific communication," said Niimura.

Regardless of its shape, no protein can function without being in the proper location. In ESP proteins, the alpha-globin-derived portion is attached to a signaling portion, which directs the protein to be secreted from salivary and tear glands. Researchers identified the ESP genes' location signaling sequence as resembling that of CRISP2, a gene expressed in mammalian reproductive tracts and salivary glands as well as the venom gland of some snakes.

The hemoglobin and CRISP genes are both ancient genes that existed in the shared evolutionary ancestor of vertebrates - all animals with a backbone - over 500 million years ago. The genetic shuffling that created ESP genes occurs relatively frequently in the cells of all organisms, but for these changes to become inherited evolutionary traits, the changes must occur in the sex cells so they can be passed on to future generations.

"The creation of new genes is not done from scratch, but nature utilizes pre-existing material. Evolution is like a tinkerer, using old things and broken parts to create some new device with a useful function," said Niimura.

Niimura and his colleagues plan to use their new understanding of the evolution of this one family of pheromones to direct their search for new pheromones. The short length of many known pheromone genes makes it likely that similar pheromones are overlooked in standard genome searches. They also predict that salivary and tear glands, often overlooked because their small size makes them inconvenient tissues to study, may contain interesting future discoveries.

Researchers at Hiroshima University have taught an AI to look at post-disaster aerial images and accurately determine how battered the buildings are — a technology that crisis responders can use to map damage and identify extremely devastated areas where help is needed the most.

Quick action in the first 72 hours after a calamity is critical in saving lives. And the first thing disaster officials need to plan an effective response is accurate damage assessment. But anyone who has seen aftermath scenes of a natural catastrophe knows the many logistical challenges that can make on-site evaluation a danger to the lives of crisis responders.

Using convolutional neural network (CNN) — a deep learning algorithm inspired by the human brain’s image recognition process — a team led by Associate Professor Hiroyuki Miura of Hiroshima University’s Graduate School of Advanced Science and Engineering trained an AI to finish in an instant a task that usually requires us to devote crucial hours and personnel at a time when resources are scarce.

Previous CNN models that assess damage require both before and after photos to give an evaluation. But Miura’s model doesn’t need pre-disaster images. It only relies on post-disaster photos to determine building damage.

It works by classifying buildings as collapsed, non-collapsed, or blue tarp-covered based on the seven damage scales (D0-D6) used in the 2016 Kumamoto earthquakes by the Architectural Institute of Japan.

A collapsed building is defined as D5–D6 or major damage. Non-collapse is interpreted as D0–D1 or negligible damage. Intermediate damage, which was rarely considered in previous CNN models, is designated as D2–D3 or moderate damage.

Researchers trained their CNN model using post-disaster aerial images and building damage inventories by experts during the 1995 Kobe and 2016 Kumamoto earthquakes.

The researchers overcame the challenge of identifying buildings that suffered intermediate damage after confirming that blue tarp-covered structures in photos used to train the AI predominantly represented D2-D3 levels of devastation.

Since ground truth data from field investigations of structural engineers were used to teach the AI, the team believes its evaluations are more reliable than other CNN models that depended on visual interpretations of non-experts.

When they tested it on post-disaster aerial images of the September 2019 typhoon that hit Chiba, results showed that damage levels of approximately 94% of buildings were correctly classified.

Now, the researchers want their AI to outdo itself by making its damage assessment more powerful.

“We would like to develop a more robust damage identification method by learning more training data obtained from various disasters such as landslides, tsunami, and etcetera,” Miura said.

“The final goal of this study is the implementation of the technique to the real disaster situation. If the technique is successfully implemented, it can immediately provide accurate damage maps not only damage distribution but also the number of damaged buildings to local governments and governmental agencies.”