Culture

E-cigarette, or vaping, associated lung injury (EVALI) has sickened thousands of people, most under the age of 35. Studies have linked vitamin E acetate, an oily substance in some vaping liquids, to the disorder. Now, researchers reporting in ACS' Chemical Research in Toxicology have uncovered a possible mechanism: Vitamin E acetate could increase the fluidity of lung surfactant, causing the surfactant layer to collapse, contributing to symptoms such as shortness of breath and lung inflammation.

The lungs are made up of alveoli, which are tiny cavities where gas exchange takes place. Oxygen that is breathed in diffuses across the alveolar membrane and into the capillaries, while carbon dioxide passes in the opposite direction to be exhaled. Lung surfactant, a fluid made up of lipids and proteins, coats the inner surface of the alveoli, reducing the surface tension so that the alveoli can easily inflate when someone inhales. Scientists still don't know exactly how the surfactant layer expands and contracts when a person breathes in and out, but one hypothesis is that certain lipids get "squeezed out" or expelled when the alveoli contract, and then spread across the surface again when the alveoli expand. Drew Marquardt and colleagues wondered how vitamin E acetate, which has been found in the lungs of most EVALI patients but not in healthy controls, could influence this process.

To find out, the researchers added increasing amounts of vitamin E acetate to two model lung surfactants in the lab: one containing only the lipid DPPC (the primary component of lung surfactant), and the other containing a mixture of the four major lipids in the fluid. Using a combination of neutron spin echo and small-angle neutron scattering, the team found that increasing vitamin E acetate concentration increased membrane fluidity and compressibility for both model surfactants, up to a plateau. These findings suggest that, in the presence of the vaping additive, the lung surfactant monolayer could "squeeze out" lipids prematurely during exhalation, thereby becoming unstable. However, the researchers note that these experiments were conducted in a model system without protein components or alveoli, so more work still needs to be done.

The authors acknowledge funding from the Natural Sciences and Engineering Research Council of Canada, the Ontario Graduate Scholarship program, the National Institute of Standards and Technology, the Center for High Resolution Neutron Scattering, the National Science Foundation, the WE-SPARK Health Institute and the University of Windsor.

The abstract that accompanies this paper is available here.

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The most basic activity of a living thing is to turn one copy of its genome into two copies, crafting one cell into two. That replication event begins with a set of proteins--the Origin Recognition Complex (ORC). And, with some cancers and developmental diseases linked to ORC proteins, structural biologists need to see how the complex works so they can understand how it might go wrong. Cold Spring Harbor Laboratory (CSHL) Professor & HHMI Investigator Leemor Joshua-Tor and colleagues published images of the human ORC in exquisite detail in eLife, showing how it changes shapes in dramatic ways as it assembles around DNA.

The scientists think the first piece of the complex--ORC1--finds the stretch of DNA where replication is supposed to begin and assembles the rest of the ORC (subunits 2-5) at that spot. Though, in yeast, a single sequence of DNA peppered throughout the genome spells out "start," there are no such simple signposts for the 30,000 start sites in humans. Our start signals are mysterious. Joshua-Tor says:

"When the cell has to duplicate, the first thing that has to happen is that the genome has to duplicate. And so the positioning of ORC on these so-called "start" sites is really the first event that has to happen in order to start the duplication of the genome. You know in bacteria, there's usually one start site because it's a small genome, but in larger organisms like humans, in order to be able to replicate such a large genome, what the cell does is uses many, many start sites. And the interesting thing in mammalian systems is that we actually don't understand what a start site really looks like."

To complicate things further, earlier on, as researchers looked at different organisms, they found differently shaped ORCs. But Joshua-Tor and colleagues found an explanation for those varying shapes. Parts of the ORC twist and pinch in dramatic ways, depending on what they are doing at the moment. A yeast ORC freezes mostly into one stable shape and a fly ORC into another. According to Kin On, a CSHL staff scientist, "the yeast complex is so stable, it is rock solid. But the human ORC assembly is very dynamic." Using cryo-electron microscopy (cryo-EM), sample preparation, and computer analysis techniques, the group was able to catch the human enzyme complex in many different shapes, including one that looks like a fly ORC and another that looks like yeast ORC. They assembled a series of images into a movie showing a wide range of motions. They even caught the first snapshot of a human ORC straddling a DNA molecule, which is key to understanding how ORCs do their jobs. According to Matt Jaremko, a postdoctoral fellow in Joshua-Tor's lab, "ORC is flexible, which helps the protein interact with DNA."

The ORC was discovered at CSHL in 1992 by CSHL President and CEO Bruce Stillman, a collaborator of Joshua-Tor's on this study.

Though a better understanding of ORCs may point to better treatments for cancer and developmental syndromes, Joshua-Tor says there is another reason to want to learn what we can about these beautiful cellular machines:

"How we duplicate our genome is the most basic process of life, right? Really that's what life is all about. So, regardless of how we understand cancer and this developmental syndrome, you know, understanding ourselves and understanding the most basic process, that is part of the human endeavor really to understand ourselves. So it's not all about the utility of it. It's really, y'know, one of the basic endeavors of, of humanity is trying to understand life and ourselves. I think it's a big part of why we're doing it. At least a big part of why I'm doing it."

Higher viral loads are associated with a greater risk of death among cancer and non-cancer patients hospitalized with coronavirus disease 2019 (COVID-19), researchers report September 15 in the journal Cancer Cell. Among hospitalized COVID-19 patients, those with hematologic malignancies who had recently been treated for cancer had the highest levels of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19.

"As a community, we've only begun to understand the relationship between SARS-CoV-2 viral load and outcomes," says senior study author Michael Satlin, an assistant professor of medicine in the Division of Infectious Diseases at Weill Cornell Medicine and an assistant attending physician at NewYork-Presbyterian/Weill Cornell Medical Center. "Currently, this quantitative information is not given to patient care teams, and providers only know if a patient's test is positive or negative. Giving this information to providers of patients with cancer who have COVID-19 could help them decide on which patients should receive more intensive monitoring when they are in the hospital and which should receive new antiviral medicines if these treatments are in short supply."

Worldwide, COVID-19 has affected more than 27 million people and has resulted in approximately 900,000 deaths. Initial reports have suggested that patients with cancer may be more likely to develop severe COVID-19 than patients without cancer. Satlin and his collaborators previously found that high SARS-CoV-2 viral load upon presentation to the emergency department is associated with in-hospital mortality among the general inpatient population. But until now, it was not clear how admission viral load may affect the clinical outcomes of hospitalized patients who have both cancer and COVID-19.

In the new study, Satlin and his team used two standard diagnostic tests to measure the amount of SARS-CoV-2 in nasopharyngeal swab specimens obtained upon admission to three New York City hospitals between March 15 and May 14, 2020. One hundred of the patients had active cancer, and 2,914 patients did not. Among the cancer patients, some had solid tumors, whereas others had hematologic malignancies, which affect blood, blood cell-producing tissue called bone marrow, and lymph nodes - organs making up part of the circulatory and immune systems.

Half of patients with hematologic malignancies had high viral loads, compared to approximately 30% of patients without cancer. Among patients with hematologic malignancies, only those who had received chemotherapy or targeted therapy during the previous six months had significantly higher viral loads than the general inpatient population with COVID-19.

"We suspect that this finding may be from the underlying immunodeficiencies conferred by either the hematologic malignancies or the administered therapies, which may decrease the ability to inhibit proliferation of SARS-CoV-2," says co-first author Lars Westblade, an associate professor of pathology and laboratory medicine at Weill Cornell Medicine and a clinical microbiologist at NewYork-Presbyterian/Weill Cornell Medical Center. "Additional studies with a larger sample size of patients with hematologic malignancies are needed to more definitely assess whether these patients have increased mortality when hospitalized with COVID-19."

Overall, the in-hospital mortality rate was 38.8% among patients with a high viral load, 24.1% among patients with a medium viral load, and 15.3% among patients with a low viral load. Cancer patients showed a similar pattern, with mortality rates of 45.2%, 28.0%, and 12.1%, respectively. High viral loads in patients with cancer were associated with increased in-hospital mortality than low viral loads. This finding remained statistically significant, even after adjusting for factors such as age and need for supplemental oxygen within three hours of presentation to the emergency department.

One important caveat is that it is not clear whether viral load predicts mortality rate in non-hospitalized individuals with COVID-19. "We encourage subsequent studies to assess the potential role of using SARS-CoV-2 viral load to guide care for outpatients with and without cancer," says co-first author Gagandeep Brar, an assistant professor of medicine in the Division of Hematology and Medical Oncology at Weill Cornell Medicine and an assistant attending physician at NewYork-Presbyterian/Weill Cornell Medical Center.

For their own part, the researchers plan to conduct larger studies to confirm their findings and investigate whether specific types of cancer and cancer treatments lead to higher viral loads and worse outcomes. They would also like to assess whether measuring viral loads over time in a given patient could be used to personalize the type and duration of therapy.

The culture of science is changing. Researchers are examining the methods and practices that have long been the basis for scientific research and publication with the goal of improving it. This "moment of change," the authors of a new paper write, presents an opportunity to address science's "historic lack of diversity and noninclusive culture."

For the paper, the authors examined the two paths that scientists are following: the movement for reproducibility and the movement for open science. Both movements aim to create centralized archives for data, computer code and other resources, but from there, the paths diverge. The movement for reproducibility calls on scientists to reproduce the results of past experiments to verify earlier results, while open science calls on scientists to share resources so that future research can build on what has been done, ask new questions and advance science.

The international research team, led by Indiana University (IU), finds the two movements do more than diverge. They have very distinct cultures, with two distinct literatures produced by two groups of researchers with little crossover. Their investigation also suggests that one of the movements -- open science -- promotes greater equity, diversity, and inclusivity. Their findings were reported earlier this week in a paper titled "Open science, communal culture, and women's participation in the movement to improve science," published in the Proceedings for the National Academy of Sciences.

The team's analysis of academic papers published from 2010-2017 identified with one of the two movements showed that even though both movements span widely across STEM fields, the authors within them occupy two largely distinct networks. The researchers also analyzed abstracts of the papers to determine the values implicit in the language used to define the research. Specifically, they looked at the degree to which the research was prosocial, that is, oriented toward helping others by seeking to solve large social problems.

With respect to gender, the team found that "women publish more often in high-status authorship positions in open science, and that participation in high-status authorship positions has been increasing over time in open science, while in reproducibility women's participation in high-status authorship positions is decreasing over time," according to Mary Murphy, a professor at IU and a lead author on the study.

With a core of eight lead scientists at IU, the team also included 20 more co-authors, mostly women and people of color who are experts on how to increase the participation of underrepresented groups in science; diversity and inclusion; and the movements to improve science. Among them is Valerie Jones Taylor, a faculty member in Lehigh University's Department of Psychology with a joint appointment in Africana Studies. Taylor investigates how stereotyping and prejudice affect the academic performance of underrepresented groups, interracial interactions, and the treatment of racialized physical spaces. Her work also examines ways to improve interracial encounters in academic and social contexts using virtual reality.

"Research practices that seek to improve the quality of scientific research and knowledge can benefit from what we have learned about the communal, collaborative, and prosocial ideals that mark the open science literature," says Taylor about the study. "Overall, women hold more prominent roles and participate more frequently in scientific research in the open science than the reproducibility literature. This work suggests that the prosocial norms in the open science movement encourage greater diversity and inclusion, which benefits scientific knowledge."

This study intersects with Taylor's interests in that it seeks to understand how research practices in science - a domain that can reinforce negative gender and racial stereotypes and be unwelcoming to members from underrepresented groups - can foster a more inclusive and collaborative culture.

Taylor believes that the study results "...should encourage researchers across scientific disciplines to adopt the communal and prosocial practices of the open science movement to spur constructive criticism, rigor, and innovation while promoting norms that foster scientific environments that are more welcoming and comfortable for all."

UTICA, NY -- Researchers from the Masonic Medical Research Institute (MMRI), the Precision Cardiology Lab (PCL) of the Broad Institute at MIT and Harvard, Bayer USA, Massachusetts General Hospital, and University of Pennsylvania collaborated to uncover some pressing questions about the biology of the heart. While understanding the mechanisms causal to human heart disease remain active areas of research for many scientists, important knowledge gaps about its composition and function remain unknown.

The current study, "Transcriptional and Cellular Diversity of the Human Heart," published on August 4th in the journal Circulation, sought to uncover how many different cell types comprise the heart, how each cell type differs between various regions of the heart, and how the differences relate to genetic risk and affect cardiac health. The team applied state-of-the-art approaches to identify these previously unknown signatures and created a map of the nearly 300,000 identified cells in human hearts.

Ultimately, this study increases scientists' understanding of the human heart, enabling a greater understanding of and treatments for cardiac disease. "Understanding of human cardiac biology at this resolution was not possible just a few years ago," said Dr. Nathan Tucker, Assistant Professor at MMRI and first author of the study. "We are proud of the strong collaborative effort that was required to make this important observation a reality and are excited to see where it goes and the effect it has in the near future."

The results should also serve as a resource to scientists around the world. "One of our major aims was to create a public resource to share with our research community," Tucker noted, "We are very excited to see how this facilitates studies by other groups, both as a data source for further analysis and as a roadmap for complementary work." For more information, please visit: broadinstitute.org/news/single-cell-map-heart-reveals-wide-cellular-diversity.

ITHACA, N.Y. - When stars like our sun die, all that remains is an exposed core - a white dwarf. A planet orbiting a white dwarf presents a promising opportunity to determine if life can survive the death of its star, according to Cornell University researchers.

In a study published in the Astrophysical Journal Letters, they show how NASA's upcoming James Webb Space Telescope could find signatures of life on Earth-like planets orbiting white dwarfs.

A planet orbiting a small star produces strong atmospheric signals when it passes in front, or "transits," its host star. White dwarfs push this to the extreme: They are 100 times smaller than our sun, almost as small as Earth, affording astronomers a rare opportunity to characterize rocky planets.

"If rocky planets exist around white dwarfs, we could spot signs of life on them in the next few years," said corresponding author Lisa Kaltenegger, associate professor of astronomy in the College of Arts and Sciences and director of the Carl Sagan Institute.

Co-lead author Ryan MacDonald, a research associate at the institute, said the James Webb Space Telescope, scheduled to launch in October 2021, is uniquely placed to find signatures of life on rocky exoplanets.

"When observing Earth-like planets orbiting white dwarfs, the James Webb Space Telescope can detect water and carbon dioxide within a matter of hours," MacDonald said. "Two days of observing time with this powerful telescope would allow the discovery of biosignature gases, such as ozone and methane."

The discovery of the first transiting giant planet orbiting a white dwarf (WD 1856+534b), announced in a separate paper - led by co-author Andrew Vanderburg, assistant professor at the University of Wisconsin, Madison - proves the existence of planets around white dwarfs. Kaltenegger is a co-author on this paper, as well.

This planet is a gas giant and therefore not able to sustain life. But its existence suggests that smaller rocky planets, which could sustain life, could also exist in the habitable zones of white dwarfs.

"We know now that giant planets can exist around white dwarfs, and evidence stretches back over 100 years showing rocky material polluting light from white dwarfs. There are certainly small rocks in white dwarf systems," MacDonald said. "It's a logical leap to imagine a rocky planet like the Earth orbiting a white dwarf."

The researchers combined state-of-the-art analysis techniques routinely used to detect gases in giant exoplanet atmospheres with the Hubble Space Telescope with model atmospheres of white dwarf planets from previous Cornell research.

NASA's Transiting Exoplanet Survey Satellite is now looking for such rocky planets around white dwarfs. If and when one of these worlds is found, Kaltenegger and her team have developed the models and tools to identify signs of life in the planet's atmosphere. The Webb telescope could soon begin this search.

The implications of finding signatures of life on a planet orbiting a white dwarf are profound, Kaltenegger said. Most stars, including our sun, will one day end up as white dwarfs.

"What if the death of the star is not the end for life?" she said. "Could life go on, even once our sun has died? Signs of life on planets orbiting white dwarfs would not only show the incredible tenacity of life, but perhaps also a glimpse into our future."

New University of Colorado Boulder-led research finds that the traits that make vertebrates distinct from invertebrates were made possible by the emergence of a new set of genes 500 million years ago, documenting an important episode in evolution where new genes played a significant role in the evolution of novel traits in vertebrates.

The findings, published today in Nature, show that a gene family only found in vertebrates is critical for forming the head skeleton and other traits unique to them during embryonic development.

"Every animal essentially has the same basic core set of Lego pieces to make them. What this paper shows is that vertebrates have a few special pieces in addition to that, and we identify those special pieces," said Daniel Medeiros, senior author of the paper and associate professor of ecology and evolutionary biology.

These special pieces in vertebrates are known as the Endothelin signaling pathway, a set of genes that influence how cells talk to each other. The researchers found this gene family is responsible for allowing neural crest cells--cells that develop into unique vertebrate traits like skeletal parts, pigment cells and our peripheral nervous system--to proliferate and specialize into different roles throughout the body.

Evolutionary theories have given weight to the role of genome duplication in the evolution of new traits, and for good reason. When a genome duplicates, new copies of existing genes can take on new roles in an organism. But since previous ideas were based mostly on observation, Medeiros wanted to test if gene duplication could have allowed vertebrates to become so special, or if the appearance of brand new genes could have played a role.

Medeiros and his colleagues tested the hypothesis that new gene families could also give rise to new traits by genetically modifying the larvae of sea lamprey, a type of jawless fish, through identifying and removing this specific gene family. If their prediction was correct, removing it would revert a sea lamprey during its larval development into a more invertebrate-like worm, a close evolutionary ancestor.

"And we found that by knocking out this new gene family, you can almost erase most of the key vertebrate traits that make vertebrates special," said Medeiros.

While gene duplication is still an important part of the evolutionary process--as this new gene family is also duplicated in vertebrates--they found that duplication was not as critical in giving rise to the special neural crest cell types that vertebrates evolved as was the emergence of this new gene family.

This finding is significant in part because it's rare to find clear roles for genes that are unique to vertebrates, said lead author Tyler Square, who recently completed his PhD in the Medeiros lab and is now at the University of California Berkeley.

"We thought that gene duplication was the most important thing. But here, we found both of those things [new genes and duplications] happening at once," said Square.

Reverse engineering the first fish

Fish were the first vertebrates, from which all others evolved--including humans. But there is a gap in the fossil record right when the first fish were evolving, because they had little, soft skeletons which were not preserved in the fossil record.

So how can scientists work out where the first fish came from, and therefore how all vertebrates came to be?

"Rather than looking at fossils, we use tools like molecular biology and genetics to try to understand how evolution has happened, kind of like genetic paleontology," said Medeiros. "In the deepest molecular genetic terms, we're trying to reverse engineer how a creature evolves. It's the closest you can get to Jurassic Park."

The creature they chose to reverse engineer, however, might seem a bit monstrous.

"While most people think of a big ugly hurricane of teeth sticking on to fish and chewing on them, sea lamprey are surprisingly cute when they're little baby larvae," said Square.

The sea lamprey, a jawless fish, diverged in evolution from other fish 500 million years ago. Because they hold onto several older vertebrate features, this gives the researchers the best snapshot of the early stage of vertebrate evolution with a living organism today.

"A lamprey and a human are extremely different. But by doing these kinds of studies, we can know what makes them the same," said Square. "This is stuff that's really fundamental, not just to mammals and humans, but to every vertebrate that exists."

Square and his colleagues used the gene-editing tool CRISPR during its early days to find out how important this new gene family is to making vertebrates, well, vertebrates.

"It was the wild west of CRISPR days," said Square. "But we couldn't have done this whatsoever if it weren't for CRISPR."

Not only did this technology allow the researchers to test hypotheses functionally, by knocking out genes, but they were also the first team to use CRISPR in sea lampreys. Previously, this technology had only been used in some vertebrates like mice, frogs and zebrafish.

"And that's a really narrow view of life on the planet," said Medeiros. "What CRISPR has done is democratized genetic studies across diverse organisms. It's super powerful for answering evolutionary questions."

WASHINGTON -- Researchers have developed an advanced spectrometer that can acquire data with exceptionally high speed. The new spectrometer could be useful for a variety of applications including remote sensing, real-time biological imaging and machine vision.

Spectrometers measure the color of light absorbed or emitted from a substance. However, using such systems for complex and detailed measurement typically requires long data acquisition times.

"Our new system can measure a spectrum in mere microseconds," said research team leader Scott B. Papp from the National Institute of Standards and Technology and the University of Colorado, Boulder. "This means it could be used for chemical studies in the dynamic environment of power plants or jet engines, for quality control of pharmaceuticals or semiconductors flying by on a production line, or for video imaging of biological samples."

In The Optical Society (OSA) journal Optics Express, lead author David R. Carlson and colleagues Daniel D. Hickstein and Papp report the first dual-comb spectrometer with a pulse repetition rate of 10 gigahertz. They demonstrate it by carrying out spectroscopy experiments on pressurized gases and semiconductor wafers.

"Frequency combs are already known to be useful for spectroscopy," said Carlson. "Our research is focused on building new, high-speed frequency combs that can make a spectrometer that operates hundreds of times faster than current technologies."

Getting data faster

Dual-comb spectroscopy uses two optical sources, known as optical frequency combs that emit a spectrum of colors - or frequencies - perfectly spaced like the teeth on a comb. Frequency combs are useful for spectroscopy because they provide access to a wide range of colors that can be used to distinguish various substances.

To create a dual-comb spectroscopy system with extremely fast acquisition and a wide range of colors, the researchers brought together techniques from several different disciplines, including nanofabrication, microwave electronics, spectroscopy and microscopy.

The frequency combs in the new system use an optical modulator driven by an electronic signal to carve a continuous laser beam into a sequence of very short pulses. These pulses of light pass through nanophotonic nonlinear waveguides on a microchip, which generates many colors of light simultaneously. This multi-color output, known as a supercontinuum, can then be used to make precise spectroscopy measurements of solids, liquids and gases.

The chip-based nanophotonic nonlinear waveguides were a key component in this new system. These channels confine light within structures that are a centimeter long but only nanometers wide. Their small size and low light losses combined with the properties of the material they are made from allow them to convert light from one wavelength to another very efficiently to create the supercontinuum.

"The frequency comb source itself is also unique compared to most other dual-comb systems because it is generated by carving a continuous laser beam into pulses with an electro-optic modulator," said Carlson. "This means the reliability and tunability of the laser can be exceptionally high across a wide range of operating conditions, an important feature when looking at future applications outside of a laboratory environment."

Analyzing gases and solids

To demonstrate the versatility of the new dual-comb spectrometer, the researchers used it to perform linear absorption spectroscopy on gases of different pressure. They also operated it in a slightly different configuration to perform the advanced analytical technique known as nonlinear Raman spectroscopy on semiconductor materials. Nonlinear Raman spectroscopy, which uses pulses of light to characterize the vibrations of molecules in a sample, has not previously been performed using an electro-optic frequency comb.

The high data acquisition speeds that are possible with electro-optic combs operating at gigahertz pulse rates are ideal for making spectroscopy measurements of fast and non-repeatable events.

"It may be possible to analyze and capture the chemical signatures during an explosion or combustion event," said Carlson. "Similarly, in biological imaging the ability to create images in real time of living tissues without requiring chemical labeling would be immensely valuable to biological researchers."

The researchers are now working to improve the system's performance to make it practical for applications like real-time biological imaging and to simplify and shrink the experimental setup so that it could be operated outside of the lab.

An international collaboration between researchers at Queen Mary University of London and the Chinese Academy of Science in Nanjing has led to the discovery of world's oldest animal sperm inside a tiny crustacean trapped in amber around 100 million years ago in Myanmar.

The research team, led by Dr He Wang of the Chinese Academy of Science in Nanjing, found the sperm in a new species of crustacean they named Myanmarcypris hui. They predict that the animals had sex just before their entrapment in the piece of amber (tree resin), which formed in the Cretaceous period.

Fossilised sperm are exceptionally rare; previously the oldest known examples were only 17 million years old. Myanmarcypris hui is an ostracod, a kind of crustacean that has existed for 500 million years and lives in all kinds of aquatic environments from deep oceans to lakes and rivers. Their fossil shells are common and abundant but finding specimens preserved in ancient amber with their appendages and internal organs intact provides a rare and exciting opportunity to learn more about their evolution.

Professor Dave Horne, Professor of Micropalaeontology at Queen Mary University of London said: "Analyses of fossil ostracod shells are hugely informative about past environments and climates, as well as shedding light on evolutionary puzzles, but exceptional occurrences of fossilised soft parts like this result in remarkable advances in our understanding."

During the Cretaceous period in what is now Myanmar, the ostracods were probably living in a coastal lagoon fringed by trees where they became trapped in a blob of tree resin. The Kachin amber of Myanmar has previously yielded outstanding finds including frogs, snakes and a feathered dinosaur tail. Bo Wang, also of the Chinese Academy of Science in Nanjing added: "Hundreds of new species have been described in the past five years, and many of them have made evolutionary biologists re-consider long-standing hypotheses on how certain lineages developed and how ecological relationships evolved."

The study, published in Royal Society Proceedings B, also has implications for understanding the evolutionary history of an unusual mode of sexual reproduction involving "giant sperm".

The new ostracod finds may be extremely small but in one sense they are giants. Males of most animals (including humans) typically produce tens of millions of really small sperm in very large quantities, but there are exceptions. Some tiny fruit flies (insects) and ostracods (crustaceans) are famous for investing in quality rather than quantity: relatively small numbers of "giant" sperm that are many times longer than the animal itself, a by-product of evolutionary competition for reproductive success. The new discovery is not only by far the oldest example of fossil sperm ever found but also shows that these ostracods had already evolved giant sperm, and specially-adapted organs to transfer them from male to female, 100 million years ago.

Each ostracod is less than a millimetre long. Using X-ray microscopy the team made computer-aided 3-D reconstructions of the ostracods embedded in the amber, revealing incredible detail. "The results were amazing - not only did we find their tiny appendages to be preserved inside their shells, we could also see their reproductive organs," added He Wang. "But when we identified the sperm inside the female, and knowing the age of the amber, it was one of those special Eureka-moments in a researcher's life".

Wang's team found adult males and females but it was a female specimen that contained the sperm, indicating that it must have had sex shortly before becoming trapped in the amber. The reconstructions also revealed the distinctive muscular sperm pumps and penises (two of each) that male ostracods use to inseminate the females, who store them in bag-like receptacles until eggs are ready to be fertilised.

Such extensive adaptation raises the question of whether reproduction with giant sperms can be an evolutionarily-stable character. "To show that using giant sperms in reproduction is not an extinction-doomed extravagance of evolution, but a serious long-term advantage for the survival of a species, we need to know when they first appeared" says co-author Dr Renate Matzke-Karasz of Ludwig-Maximilians-University in Munich.

This new evidence of the persistence of reproduction with giant sperm for a hundred million years shows it to be a highly successful reproductive strategy that evolved only once in this group - quite impressive for a trait that demands such a substantial investment from both males and females, especially when you consider that many ostracods can reproduce asexually, without needing males at all. "Sexual reproduction with giant sperm must be very advantageous" says Matzke-Karasz.

Tortoises are born with a natural preference for faces, according to new research from scientists at Queen Mary University of London, the University of Trento and the Fondazione Museo Civico Rovereto.

The study provides the first evidence of the tendency for solitary animals to approach face-like shapes at the beginning of life, a preference only previously observed in social species such as human babies, chicks and monkeys.

The researchers tested the reactions of hatchlings from five different species of tortoise to different patterned stimuli, made up of a series of blobs. They found that the tortoises consistently moved to areas with the 'face-like' configuration - containing three blobs arranged in an upside-down triangle shape.

The findings suggest that this early behaviour likely evolved in the common ancestors of mammals, reptiles and birds more than 300 million years ago.

Dr Elisabetta Versace, lead author of the study from Queen Mary University of London, said: "Researchers have previously observed this spontaneous attraction to faces in social animals such as humans, monkeys and chicks. Because all these species require parental care, it was thought this early adaptation was important for helping young animals respond to their parents or other members of the same species. However, now we have shown that this behaviour is also found in solitary tortoise hatchlings, suggesting it may have evolved for another reason."

Tortoises were hatched and kept away from any animal or human faces from birth until the start of the test. Each animal was then placed in the middle of a rectangular space divided into four areas containing either a face-like or control stimuli. The researchers analysed the preference of hatchlings for face-like stimuli by recording the first area the animal entered during the experimental period.

Unlike birds and mammals, tortoises are solitary species - they have no post-hatching parental care and do not form social groups as adults. Previous research has even shown that tortoise hatchlings ignore or avoid members of the same species in early life.

Silvia Damini from the University of Trento, said: "It is possible that this preference for face-like stimuli enhances learning from living animals in both social and solitary species from the early stages of life. In fact, other animals can provide information on important environmental factors, such as the availability of resources".

Gionata Stancher, Head of the Tortoise Sanctuary Sperimentarea (Fondazione Museo Civico Rovereto, Italy) where the experiments were conducted, said: "Being able to recognise and respond to cues associated with other living animals could help young animals acquire information vital for their survival."

Artificial intelligence researchers at North Carolina State University have improved the performance of deep neural networks by combining feature normalization and feature attention modules into a single module that they call attentive normalization (AN). The hybrid module improves the accuracy of the system significantly, while using negligible extra computational power.

"Feature normalization is a crucial element of training deep neural networks, and feature attention is equally important for helping networks highlight which features learned from raw data are most important for accomplishing a given task," says Tianfu Wu, corresponding author of a paper on the work and an assistant professor of electrical and computer engineering at NC State. "But they have mostly been treated separately. We found that combining them made them more efficient and effective."

To test their AN module, the researchers plugged it into four of the most widely used neural network architectures: ResNets, DenseNets, MobileNetsV2 and AOGNets. They then tested the networks against two industry standard benchmarks: the ImageNet-1000 classification benchmark and the MS-COCO 2017 object detection and instance segmentation benchmark.

"We found that AN improved performance for all four architectures on both benchmarks," Wu says. "For example, top-1 accuracy in the ImageNet-1000 improved by between 0.5% and 2.7%. And Average Precision (AP) accuracy increased by up to 1.8% for bounding box and 2.2% for semantic mask in MS-COCO.

"Another advantage of AN is that it facilitates better transfer learning between different domains," Wu says. "For example, from image classification in ImageNet to object detection and semantic segmentation in MS-COCO. This is illustrated by the performance improvement in the MS-COCO benchmark, which was obtained by fine-tuning ImageNet-pretrained deep neural networks in MS-COCO, a common workflow in state-of-the-art computer vision.

"We have released the source code and hope our AN will lead to better integrative design of deep neural networks."

In the first research of its kind, a new University of California, Davis, study suggests that for the most part, people formulate goals consistent with their personality traits -- and an individual's goals are related to how their personality subsequently changes over time.

The study surveyed more than 500 students when they started college, each year during college, and 20 years later on their goals related to being creative, having a successful career, having a family, being wealthy, or being active in religion or politics. The goals of these UC Berkeley students -- about half were still responding after two decades -- remained relatively stable over time, though there were some notable changes.

"This study was a unique opportunity to examine how individuals' personalities and major life goals were related to each other across two decades of life," said Olivia E. Atherton, the lead author of the study and former doctoral student in psychology at UC Davis. "We found that, in many ways, one's personality shapes the types of life goals that are valued, and as a result of pursuing those goals, personality changes."

Successful people stress goals

Various enormously successful people, such as Albert Einstein, have noted the importance of goals, researchers said. Einstein once said, for example: "If you want to live a happy life, tie it to a goal, not to people or things." The personality characteristics he possessed were likely the driving force behind the types of goals he aimed to achieve, researchers said.

"Einstein's tendency to be creative, curious, and intellectual likely fueled his scientific goals, as well as his more aesthetic goals, such as his passion for playing the violin," the study authors wrote.

The study, "Stability and Change in Personality Traits and Major Life Goals from College to Midlife," was published in late August in the Personality and Social Psychology Bulletin.

Besides Atherton, co-authors include Richard Robins, a professor of psychology who is director of the UC Davis Personality, Self and Emotion Lab; as well as Emily Grijalva, University of Buffalo; and Brent W. Roberts, University of Illinois, Urbana-Champaign.

The personality traits examined in the present study are termed the "Big Five" in psychology. They are neuroticism, extraversion, openness to experience, agreeableness and conscientiousness. These five traits broadly capture most of the ways in which people differ from one another, and they are related to a wide range of important life outcomes.

Researchers examined these traits, along with aesthetic goals (wanting to be creative and artistic); economic goals (wanting to have a successful career and be wealthy); family/relationship goals (wanting to be married and have children); hedonistic goals (wanting to have fun and experience pleasure); political goals (wanting to have influence in public affairs); religious goals (wanting to participate in religious institutions); and social goals (wanting to help others in need).

"... We found that, on average, individuals increased in agreeableness and conscientiousness, decreased in neuroticism, and showed little change in openness to experience and extraversion from age 18 to 40," researchers said.

Some goals become less relevant

They also found that people place less importance on all goals over time, suggesting that individuals winnow the goals they value with age, presumably because they are achieving milestones associated with those goals and thus, the goals become less important as a result.

"By identifying their own personal strengths and limitations, middle-aged adults may place less importance on certain major life goals because some goals may no longer be viewed as self-relevant," researchers said.

The authors did find that personality traits are related to major life goal development over time. For example, individuals who become more agreeable, kind and compassionate, also tend to place more emphasis on social and family/relationship goals over time. And, individuals who become more responsible, organized and self-controlled tend to value more economic and family goals.

Researchers at Helmholtz Zentrum München and the Technical University of Munich (TUM) have developed the world's smallest ultrasound detector. It is based on miniaturized photonic circuits on top of a silicon chip. With a size 100 times smaller than an average human hair, the new detector can visualize features that are much smaller than previously possible, leading to what is known as super-resolution imaging.

Since the development of medical ultrasound imaging in the 1950s, the core detection technology of ultrasound waves has primarily focused on using piezoelectric detectors, which convert the pressure from ultrasound waves into electric voltage. The imaging resolution achieved with ultrasound depends on the size of the piezoelectric detector employed. Reducing this size leads to higher resolution and can offer smaller, densely packed one or two dimensional ultrasound arrays with improved ability to discriminate features in the imaged tissue or material. However, further reducing the size of piezoelectric detectors impairs their sensitivity dramatically, making them unusable for practical application.

Using computer chip technology to create an optical ultrasound detector

Silicon photonics technology is widely used to miniaturize optical components and densely pack them on the small surface of a silicon chip. While silicon does not exhibit any piezoelectricity, its ability to confine light in dimensions smaller than the optical wavelength has already been widely exploited for the development of miniaturized photonic circuits.

Researchers at Helmholtz Zentrum Mu?nchen and TUM capitalized on the advantages of those miniaturized photonic circuits and built the world's smallest ultrasound detector: the silicon waveguide-etalon detector, or SWED. Instead of recording voltage from piezoelectric crystals, SWED monitors changes in light intensity propagating through the miniaturized photonic circuits.

"This is the first time that a detector smaller than the size of a blood cell is used to detect ultrasound using the silicon photonics technology", says Rami Shnaiderman, developer of SWED. "If a piezoelectric detector was miniaturized to the scale of SWED, it would be 100 million times less sensitive."

Super-resolution imaging

"The degree to which we were we able to miniaturize the new detector while retaining high sensitivity due to the use of silicon photonics was breathtaking", says Prof. Vasilis Ntziachristos, lead of the research team. The SWED size is about half a micron (=0,0005 millimeters). This size corresponds to an area that is at least 10,000 times smaller than the smallest piezoelectric detectors employed in clinical imaging applications. The SWED is also up to 200 times smaller than the ultrasound wavelength employed, which means that it can be used to visualize features that are smaller than one micrometer, leading to what is called super-resolution imaging.

Inexpensive and powerful

As the technology capitalizes on the robustness and easy manufacturability of the silicon platform, large numbers of detectors can be produced at a small fraction of the cost of piezoelectric detectors, making mass production feasible. This is important for developing a number of different detection applications based on ultrasound waves. "We will continue to optimize every parameter of this technology - the sensitivity, the integration of SWED in large arrays, and its implementation in hand-held devices and endoscopes", adds Shnaiderman.

Future development and applications

"The detector was originally developed to propel the performance of optoacoustic imaging, which is a major focus of our research at Helmholtz Zentrum München and TUM. However, we now foresee applications in a broader field of sensing and imaging", says Ntziachristos.

While the researchers are primarily aiming for applications in clinical diagnostics and basic biomedical research, industrial applications may also benefit from the new technology. The increased imaging resolution may lead to studying ultra-fine details in tissues and materials. A first line of investigation involves super-resolution optoacoustic (photoacoustic) imaging of cells and micro-vasculature in tissues, but the SWED could be also used to study fundamental properties of ultrasonic waves and their interactions with matter on a scale that was not possible before.

Tropical Storm Karina was making night moves like the old Bob Seger song. NASA-NOAA's Suomi NPP satellite provided an infrared image of Tropical Storm Karina's nighttime movement as it moved away from the Baja California peninsula of Mexico. Infrared data showed the storm was weakening.

NASA's Night-Time View of Karina's Weakening

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP was used to capture a nighttime image of Karina. NASA-NOAA's Suomi NPP satellite passed over the Eastern Pacific Ocean during the early morning of Sept. 16 at 3 a.m. PDT/6 a.m. EDT (1000 UTC) and captured a nighttime image of Tropical Storm Karina moving farther away from Baja California, Mexico.

The infrared imagery revealed that there was very little deep convection (and building thunderstorms). Cloud top temperatures were near minus 40 degrees Celsius, which indicates they are warming and cloud heights are dropping. It is an indication that the uplift in the storm is weakening, and thunderstorm development drops off. The coldest cloud tops were found well to the west-northwest of the center of circulation.

The image was created using the NASA Worldview application at NASA's Goddard Space Flight Center in Greenbelt, Md.

Karina's Status on Sept. 16

At 11 a.m. EDT (1500 UTC), the center of Tropical Storm Karina was located near latitude 22.6 degrees north and longitude 123.9 degrees west.  Karina is moving toward the northwest near 8 mph (13 kph), and a turn back toward the west-northwest is forecast today.  A slower westward motion is expected toward the end of the week. Maximum sustained winds are near 40 mph (65 kph) with higher gusts. Continued weakening is forecast, and Karina is expected to become a remnant low by tonight. The estimated minimum central pressure is 1004 millibars.

Karina's Forecast

"Karina is expected to continue traversing cooler waters while moving farther into an inhibiting thermodynamic environment and unfavorable upper-level winds," noted U.S. Navy Hurricane Specialist Dave Roberts of NOAA's National Hurricane Center in Miami, Fla. "Therefore, weakening is forecast and Karina should degenerate to a remnant low [pressure area] tonight."

Diversity in many biological communities is a sign of an ecosystem in balance. When one species dominates, the entire system can go haywire. For example, the uncontrolled overgrowth of certain oceanic algae species causes toxic red tides that kill fish and other sea life, and sicken humans. On a more individual level, the human gut hosts a large community of different bacteria that is crucial for proper digestion and absorption of nutrients. Disruption of or imbalances in this bacterial community can cause a bloom in the growth of a toxic species, causing nausea, diarrhea and other illnesses. Plainly, there's an urgent need to understand how microbial community diversity is developed and maintained, especially as human activities change our external and internal environments.

Like all life, microbes require certain nutrients, such as sunlight, sugars or nitrogen sources, to survive and reproduce. Many microbe species' nutrient requirements overlap, putting them in competition with each other. Much effort has been devoted to understanding how this competition influences microbial diversity when nutrients are steadily supplied. However, in nature, it's quite common for the resources to be available only seasonally so that their supply is severely limited at least some of the time. For example, bacteria in the gut that live on sugars might find these abundant right after the human's had a meal, and scarcer the rest of the time. Because each bacterial species is genetically unique, it will have its own particular strategy for using a given nutrient. Species with the most efficient strategies for using the available nutrients experience the best growth.

"A long-standing question about microbes concerns how so many different microbial species manage to coexist when competing for limited resources," said Ned Wingreen, a professor in Princeton's Department of Molecular Biology and the senior author on a paper in the Sept. 11 issue of the journal eLife.

Researchers can recreate seasonal nutrient supply in a laboratory by placing bacteria in a container with nutrients, letting them grow, then taking a small sample and moving it to a new container of nutrients -- a process called "serial dilution." Over time, the relative abundance of different species in the culture will change according to the nutrients available and the species' nutrient use strategies. By performing repeated rounds of serial dilution, scientists can observe the effects of seasonally supplied nutrients on community diversity.

Of course, it would be impractical to examine all possible combinations of bacteria, nutrients and nutrient utilization strategies using this method. Instead, associate research scholar Amir Erez and graduate student Jaime Lopez, co-authors on the paper and members of Wingreen's lab, and their collaborators investigated this question by mathematically modeling serial dilution.

"In our paper, we develop a general theory of microbial resource competition in a seasonal ecosystem by modeling recurrent nutrient addition and depletion," explained Wingreen.

When nutrients are only seasonally available, the modeling uncovered a surprising relationship between species diversity and the amount of nutrients supplied. First, species diversity is high when all nutrients are supplied in very high amounts because growth of all species is equally unlimited at high nutrient levels. Diversity is also high at very low nutrient amounts because growth of all species is restricted under such conditions and no species can gain an advantage.

"Nutrient-consumption trade-offs in seasonal ecosystems can lead to stable ecosystems that support diversity beyond what is predicted by simpler mathematical models," observed Wingreen.

At intermediate nutrient levels, however, species diversity nose-dives because there will always be one species whose ability to use the most abundant nutrient present outstrips that of others. This species, which the authors call the "early bird," gains an early growth advantage the others can never make up for.

"The early bird species use their earlier access to nutrients to exclude their not-so-early competitors," explains Wingreen. "The early bird is efficient at consuming easily accessible nutrients and uses its early advantage to out-compete competitors for nutrients that are not as easily accessible."

The early bird effect crops up even in more elaborate versions of the model that allow species to feed off others' metabolic byproducts, or for members of a dwindling species to be replenished by in-migration of new individuals. But the identity of the early bird, or whether there will even be one, shifts according to the inputs of the model: what nutrients are present and in what amounts; how often nutrients are supplied; and which species are present and what their strategies are. Whenever it appears, the early bird influences how the ecosystem responds to nutrient changes.

"Ecologists have long sought a universal relationship between biodiversity and the amount of nutrient supplied to a community. The existence of this universal relationship is not supported by our model," says Wingreen.

"This is an important paper," says Alvaro Sanchez, a professor in ecology and evolutionary biology at Yale University and an editor at eLife. "It provides an elegant modeling framework to understand how nutrient supply and competition can structure coexistence and diversity in microbial communities, and it will motivate new experiments."