Earth

In the paper, 'Tracking Reactions of Asymmetric Organo-Osmium Transfer Hydrogenation Catalysts in Cancer Cells', published in the journal Angewandte Chemie, researchers from the University of Warwick have, for the first time, used the new 185 m beamline to track Osmium in a single cancer cell at a scale of 100 nanometers.

They used two techniques to track potential treatments in cancer cells, the first, ICP-MS, which stands for Inductively Coupled Plasma-Mass Spectrometry, can quantify a wide range of natural and drug elements in millions of cells. However, to investigate a single cancer cell, researchers used synchrotron X-ray Fluorescence (XRF) imaging.

Using a hard-x-ray nanoprobe beamline, researchers from the University of Warwick observed how Osmium reacted in a single lung cancer cell. However, the reactivity of Osmium is determined by its coating (its ligands), so they monitored the ligands too in the same XRF experiment by labelling them with Bromine.

Once the Osmium was in the cell researchers observed that Osmium stays in the cytoplasm, whereas the ligands entered the nucleus, potentially indicative of dual attack on the cancer cell.Caption: Detection of an anticancer compound in a cancer cell, the pink is the Bromine and orange in Osmium Credit: University of Warwick

Professor Peter Sadler, from the Department of Chemistry at the University of Warwick comments:

"With one in two people getting cancer in their lifetime, the need to find new drugs has never been more urgent. Part of drug discovery is seeing exactly how they react and work in cells."

"Osmium is a rare precious metal, however, since it can act as a catalyst, a very little amount is needed for reactions in the cancer cell, therefore it could be a sustainable treatment going forward. We wanted to see how exactly it worked in a single cancer cell, which involved a variety of novel techniques, including taking water molecules out of the cell and rapidly flash-freezing it. Whereas usually cells are chemically altered to see the reactions, in our method they are close to their natural state, making our results more authentic."

Dr Elizabeth Bolitho, from the Department of Chemistry and Diamond adds:

"We worked 24 hours a day, 5 days a week to collect these exciting data, allowing us to see inside cancer cells to a nanoscale resolution. This has provided crucial insights into potential cellular targets of such Osmium catalysts.

"Not only were we able to track the Osmium in a lung cancer cell, but more widely in breast cancer, ovarian and prostate cancer cells, for example, which provides hope that in the future Osmium could be used to treat a range of different cancers."

Professor Sadler added: "Our team hopes to progress their discoveries through pre-clinical development towards new Osmium drugs for cancer treatment, although this typically takes several years. If we succeed, then the days and sleepless nights spent collecting XRF data at the Diamond synchrotron will certainly have been worthwhile."

Paul Quinn, Imaging group leader at Diamond Light Source added:

"The collaboration between Warwick and the I14 beamline is very exciting. Our research has exploited the advanced nano-imaging methods we've developed and built at Diamond to neatly image the location of these drugs within cancer cells and gain significant insights into how they interact."

Gravity might play a bigger role in the formation of elementary particles than scientists used to believe. A team of physicists from RUDN University obtained some solutions of semi-classical models that describe particle-like waves. They also calculated the ratio between the gravitational interaction of particles and the interaction of their charges. The results of the study were published in the Universe journal.

Due to their small size, the gravitational interaction between elementary particles (electrons, protons, and neutrons) is weak compared to Coulomb forces--attraction and repulsion determined by charge. For example, negatively charged electrons move around the atomic nucleus that contains positively charged protons. Therefore, the ratio of Newtonian attraction to Coulomb repulsion (or γ,) is negligible. However, on the Planck scale, i.e. at distances around 1.6?10?35 m, these forces become comparable. A team of physicists from RUDN University found solutions of existing models that correspond to particles in the Planck's range.

"Gravity can potentially play an important role in the microworld, and this assumption is confirmed by certain data. γ is considered a 'magical' dimensionless number, and we are unaware of any serious attempts to theoretically obtain such a small value of γ -- 10-40. We presented a simple model that allowed for obtaining this particular value in a natural way," said Vladimir Kassandrov, PhD, and an Assistant Professor of the Institute of Gravitation and Cosmology, RUDN University.

The team used semi-classical models based on electromagnetic field equations. They have several solutions for particles as well as solitons (stable solitary waves). In equations like this, gravity is usually not taken into consideration and is replaced with a nonlinear correction that is chosen almost arbitrarily. This is where the main issue with these models lies. However, it can be solved by adding the equations of three fundamental fields to the system. Then, following the requirements of gauge invariance (that prevent physical values from changing simultaneously with the transformation of the fields), the form of nonlinearity becomes strictly defined. The team from RUDN University used this approach to find solutions that matched the characteristics of typical elementary particles. The existence of such solutions would confirm the fundamental role of gravity in the formation of particles.

The team failed to find solutions in which the charge and mass matched elementary particles at γ

"Although our attempt to calculate probability characteristics at γ

Humans, like most social animals, tend to be organized hierarchically. In any group or social relationship there are always individuals who, for various reasons, significantly influence the behaviour of others. These individuals are attributed the highest status within the social group they belong to. As everyday examples of hierarchical relationships we find those of parents and children, teachers and students, bosses and workers, etc.

Given the pervasiveness of such social organization, in recent years studies have begun to ascertain how and when children begin to recognize which people have higher and which have lower social status. Specifically, the relationship was studied between social status and the "ability to control limited resources". This was the starting point for a study published on 10 February in the journal PLOS ONE by Jesús Bas and Núria Sebastián-Gallés, members of the Speech Acquisition and Perception research group (SAP) of the Center for Brain and Cognition (CBC), attached to the UPF Department of Information and Communication Technologies (DTIC).

Studying power relations beyond physical strength

"Individuals that control resources are usually the ones that have a higher position within the group and vice versa. Different studies have shown that before the age of 15 months (Mascaro & Csibra, 2012), children understand that people who control one resource usually control others", explains Jesús Bas, first author of the study. Most of these studies were based mainly on the control of resources by means of physical strength. "Hence, at the Infant Research Laboratory (LRI) at UPF, we decided to study whether children are also able to identify individuals with a higher social status when physical strength does not come into the equation".

"So, we designed a study in which children aged 15-18 months repeatedly observed how two people wanted to grab a teddy bear at the same time. One of them (always the same) got it, thus displaying their "social power". Unlike in other studies, physical strength was not used, rather it looked like one of the agents yielded the teddy bear to the other, thus showing respect", say the authors of the article.

After, there was a change of scene and the two agents wanted to sit in the same chair. The children were presented with two different endings: the person who had got the teddy bear sat in the chair, or the person who had yielded it sat in the chair. When studying the children's reactions, we found that only the older children (18 months) were surprised when the person who had yielded the teddy bear sat in the chair. In other words, 18-month-olds , but not 15-month-olds, expected the same person who "controlled the teddy bears" to be the one who would have "control of the chair".

This study shows that before the age of two, children are able to infer social status without the need to witness how one individual dominates the other. In addition, the researchers found differences compared to previous studies. The fact that the younger infants (15 months) were not surprised by our study suggests that representing social status is more complex when it is not associated with physical force. The results demonstrate that children are able to understand complex social relationships beyond those established through primary mechanisms such as physical strength.

In Switzerland and other European countries, drug prices are regulated to ensure affordable access to drugs. In the last few years, many European countries have introduced rebate schemes for drugs. In most cases, however, the rebates negotiated with the manufacturer are confidential. This means that a country basically has two prices for a drug: an official, higher price and an actual, lower price. Price comparisons of drugs between countries is frequently based on the higher price. Switzerland too has introduced such rebates, which are often confidential, and plans to anchor this practice in the regulation. The Federal Social Health Insurance Act is currently under revision.

National authorities and drug manufacturers justify the lack of transparency by arguing that this strategy enables quicker access to innovative and higher-priced drugs, and that this strategy could also help save costs. A research team of UZH Professor Kerstin N. Vokinger assessed these arguments based on an empirical analysis.

Drugs with a rebate often have no high clinical benefit

The UZH scientists identified 51 drugs for which rebates were granted in Switzerland between January 2012 and October 2020. Of these drugs, 32 (63%) were cancer drugs. On the basis of an established benefit evaluation system, only 15 of the 51 drugs (29%) had a high benefit, and 25 (49%) had a low benefit. The benefit could not be determined for 11 (22%) of the drugs. This shows that rebates are not limited to innovative drugs. Overall, there has been a strong increase in drugs for which rebates have been granted in recent years.

The researchers also found that there is substantial variance in terms of prices and rebates granted: Rebates are not limited to high-price drugs. The monthly treatment costs of such drugs ranged from approx. CHF 3,000 to 35,000. The rebates that were disclosed transparently also ranged widely, with price reductions between 4% and 58%.

Longer procedures, rising prices

Pricing negotiations between the pharmaceutical manufacturer and the national authority lasted more than twice as long for drugs with rebates (median of 302 days) compared to drugs without rebates (median of 106 days). "Our study shows that in the case of drugs for which a rebate is granted, patient access can be impaired, among other things, because such rebate systems can lead to increasing drug prices, at least in the medium term," explains Vokinger, who led the study.

This is even more true given that the so-called foreign price comparison (also referred to as "external reference pricing") is a decisive criterion in pricing in almost all European countries. The comparison is a regulatory instrument designed to ensure that drug prices in Switzerland are similar to prices in comparable countries. However, the strategy of secret rebates leads to a situation where the official, higher price is used as the reference. This means all countries orient themselves to the higher prices, which may result in increasing drug prices.

Calls for transparent cooperation

"This growing lack of transparency isn't in the interests of either patients or society at large," says Vokinger. She is convinced that only transparent prices that reflect reality will enable effective price regulation. This is also called for in a WHO resolution that Switzerland is backing. Closer cooperation between individual European countries could help national authorities make better informed decisions when setting drug prices. "This could also improve patient access to innovative therapies," explains Vokinger.

The researchers analysed how Spanish children and adolescents get to school, based on studies examining the commuting patterns of 36,781 individuals over a 7-year period (2010-2017)

Researchers from the University of Granada (UGR) have conducted the most comprehensive study to date on how Spanish children and young people get to school each day, to determine the active commuting rate.

The results showed that, between 2010 and 2017, in the region of 60% of Spanish children and adolescents actively commuted to school, with no significant variations being observed during this period.

The study, which was recently published in the prestigious Scandinavian Journal of Medicine & Science in Sports, analysed information drawn from 28 studies conducted throughout Spain, covering a total sample of 36,781 children and adolescents. To date, no study has been performed in Spain with such a large sample and such a longitudinal perspective, based on data collected over 7 successive years.

The results show how the overall trend of active commuting to school remained stable during 2010-2017, except for a sporadic increase in the rate among adolescents in 2012-2013. The UGR researchers highlight how promising these results are, as all similar studies previously carried out in different countries and in Spain showed a dramatic decline in the percentage of young people showing active mobility over time. Furthermore, they highlight that no significant association was found between the rate of active commuting to school and the period of economic crisis that Spain underwent in the period analysed.

The findings therefore indicate that the commitment shown in today's society toward promoting measures and strategies for increasing active commuting to school seems to be paying dividends. This activity is not only good for young people's health but is also beneficial for the environment, and efforts must continue to ensure long-term positive results in the quest for a more active society and a healthier environment.

A new X-ray imaging scanner to help surgeons performing breast tumour removal surgery has been developed by UCL experts.

Most breast cancer operations are what are known as conserving surgeries, which remove the cancerous tumour rather than the whole breast. Second operations are often required if the margins (edges) of the extracted tissue are found to not be clear of cancer.

Researchers at UCL, Queen Mary University of London, Barts Health NHS Trust and Nikon used a new approach to x-ray imaging which allows surgeons to assess extracted tissue intraoperatively, or during the initial surgery, giving 2.5 times better detection of diseased tissue in the margins than with standard imaging.

In the paper, published today in Scientific Reports, academics use X-Ray Phase Contrast Imaging (XPCI), developing a scanner which provides surgeons with a full 3D image of the extracted tissue lump, known as a wide local excision (WLE).

Currently, the WLE is assessed through histopathology - the microscopic examination of tissue - with results only available after several days. If affected margins are detected, often a second operation is required.

Lead author Professor Alessandro Olivo (UCL Medical Physics & Biomedical Engineering) said: "I am terribly excited about these results, as they are likely to lead to the first clinical use of XPCI. The technology has tremendous potential, and I am sure once people see what it can do many other clinical areas will follow suit."

So far, most proposed approaches to allowing an intraoperative assessment had too many shortcomings to be effective, either in the ability to detect all of the diseased tissue or in achieving a sufficient penetration depth in the specimen, or in both.

Researchers tested the scanner on 101 WLEs and compared the results with the current standard method used intraoperatively (based on conventional x-rays). The superior detection rate of 2.5 times could result in a similar reduction in the re-operation rate.

Co-author Professor Louise Jones (Director, Breast Cancer Now Tissue Bank) said: "This technology has the potential to significantly improve radiological intraoperative assessment of tumour margins, potentially reducing the need for repeat operations that many patients require, which can cause significant distress to the patient."

Co-author Tamara Suaris (Consultant Breast Radiologist, Barts NHS Health Trust) added: "Although we have focused on the impact of XPCI in breast surgery, there is a much wider clinical potential of this technology including other intraoperative areas such as intestinal, oesophageal and prostatic surgery and in the longer term, diagnostic imaging, notably mammography."

XPCI imaging provides soft tissue sensitivity which is superior to conventional x-ray. Whereas standard imaging picks up the x-ray beam's change in intensity as it travels through tissue, phase contrast imaging measures the changes in speed with which x-ray travels through different tissues, which has been proven to enhance soft tissue contrast, including of breast tumours.

The work was supported by the Wellcome Trust, Royal Academy of Engineering and the Royal Society. Tissue samples were collected and made available by the Breast Cancer Now Tissue Bank, donated by anonymous patients.

The millions of people affected by 2020's record-breaking and deadly fires can attest to the fact that wildfire hazards are increasing across western North America.

Both climate change and forest management have been blamed, but the relative influence of these drivers is still heavily debated. The results of a recent study show that in some ecosystems, human-caused climate change is the predominant factor; in other places, the trend can also be attributed to a century of fire suppression that has produced dense, unhealthy forests.

Over the past decade, fire scientists have made major progress in understanding climate-fire relationships at large scales, such as across western North America. But a new paper published in the journal Environmental Research Letters details a study that takes this progress to the next level.

Researchers at five Western universities delved into which factors are increasing fire activity at the scales where management actions are implemented, and when and where ecosystems are likely to benefit from fuel management. They looked at data gathered across complex terrain in two mixed-conifer watersheds, in the Idaho Batholith and the Central Rocky Mountains.

Key findings include:

In one watershed, climate change was the key driver increasing burn probability and the frequency of large fires; in the other, fire suppression dominated in some locations.

Climate change increased burn probability and led to larger, more frequent fires in locations where soil aridity was relatively low.

In the most arid locations, climate change promoted drought stress and reduced fine fuel loads, which in turn reduced burn probability.

In intermediately arid locations, the effects of climate change and fire suppression varied in response to local trade-offs between flammability and fuel loading.

"This paper presents one of the first wildfire attribution studies at the scale of actionable management and shows that local responses to climate change and fire suppression can be highly variable even within individual watersheds," said lead author Erin Hanan from the University of Nevada, Reno.

Hanan is a researcher with the University's Experiment Station and Assistant Professor of Natural Resources & Environmental Science in the College of Agriculture, Biotechnology & Natural Resources. She and her collaborators at UC Merced, UC Santa Barbara, Washington State University and the University of Washington, Tacoma, used a novel modeling approach to examine how climate change and fire suppression influence fire regimes across watersheds.

Their approach integrates three research methods: (1) remote sensing data to characterize past fires; (2) climate models to determine the role climate change has played in local meteorological patterns, including temperature, rainfall and humidity; and (3) a watershed model that simulates how climate, water, vegetation and wildfire interact over space and time.

The scientists' work uses climate records developed through a National Science Foundation-funded initiative called FireEarth and a watershed model developed at UC Santa Barbara, and expanded through another National Science Foundation-funded initiative called SERI-Fire.

"This study is really the first to directly compare the independent effects of climate change versus fire suppression, which you can only do using dynamic models," said UC Merced Assistant Professor Crystal Kolden, who led the FireEarth initiative. "We were actually surprised that the climate change signal was so clear; that's kind of rare. And even though our study was limited to Idaho, the forest types and climate we modeled are found throughout the western U.S., so they are good analogs for many other watersheds."

In addition to illuminating the roles of major wildfire factors, the research also boosts methodology.
"This paper moves fire modeling and prediction forward by looking inside watersheds and disentangling the many factors that influence how fire regimes will evolve in the coming decades," said UC Santa Barbara Professor Naomi Tague, who led the SERI-Fire initiative.

While climate change remains a major factor, increasing the frequency and intensity of large wildfires across the globe, there are many regions where past suppression efforts still play an important role. Forest-density reduction is often the approach used in fuel-limited forests where decades of suppression have significantly increased fuel loads. However, density reductions sometimes have unintended consequences, particularly when vegetation growth is enhanced by the treatments, leading to greater plant water use, drier conditions - including drier fuels - and an increased fire risk.

Because fuel management often occurs at fine scales, spatially explicit models are needed to project how different areas within watersheds will respond to fire suppression or fuel treatments under the shifting conditions brought about by climate change.

"We found that the effects of climate change and fuels varied at fine scales within watersheds, and the relative influence of these drivers is changing as the climate continues to warm, so solutions to the growing wildfire problem must be adaptive and location-based," Hanan said. "That's why it's important to consider local environmental conditions and climate change trends in policy and management planning for the future."

Scientists have discovered a never-before-seen biodiversity pattern of coral reef fishes that suggests some fishes might be exceptionally vulnerable to environmental change.

A new study shows plankton-eating coral reef fishes (planktivores) are far more diverse than others in the Indo-Australian Archipelago, a global marine biodiversity hotspot.

The findings highlight, for the first time, a unique link between the diet and distribution of species across the marine realm.

"The archipelago is one of the most complex and dynamic geological regions in the tropics," said lead author Dr Ale Siqueira from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE at JCU). "And its fishes underpin its status as a biodiversity hotspot."

"The exceptional success of planktivores may be a result of the hotspot's unique geological configuration and oceanographic currents, which ensure a constant and abundant source of planktonic food," said co-author Professor David Bellwood, also from Coral CoE at JCU.

"Such stable conditions over the past five million years are likely to have promoted the accumulation of planktivorous fish species in the hotspot."

While planktivores thrive in the hotspot, they have had a difficult history in more remote areas with the possibility of food shortages and periodic extinctions.

"Planktivore richness drops abruptly away from the marine hotspot--and more so than any of the other dietary categories studied," Dr Siqueira said.

These findings suggest a vulnerability of planktivorous coral reef fishes to environmental change, despite their species richness within the hotspot.

"We examined the global diversity patterns for more than 3,600 coral reef fishes," said co-author Dr Pete Cowman from Coral CoE at JCU and Queensland Museum.

Dr Cowman said the research identified a link between biodiversity, food and habitat--emphasising the importance of species interactions with their environment.

"Understanding the ecosystem roles of different species and how they have changed through space and time offers the potential for exciting new insights, as revealed by our planktivores," said Dr Cowman.

Dr Siqueira said a deeper understanding of species interactions is needed.

"Future research should focus on the ecosystem roles that different species play," Dr Siqueira said.

"We need to describe changes in the roles of species through space and time, rather than simply documenting species and their numbers; the traditional approach in science."

UNIVERSITY PARK, Pa. -- Like a scene from a horror movie, tomato fruitworm caterpillars silence their food plants' cries for help as they devour their leaves. That is the finding of a multidisciplinary team of researchers, who said the results may yield insights into the abilities of crop plants -- such as tomato and soybean -- to withstand additional stressors, like climate change.

"We have discovered a new strategy whereby an insect uses saliva to inhibit the release of airborne plant defenses through direct manipulation of plant stomata," said Gary Felton, professor and head of the Department of Entomology at Penn State, noting that stomata are tiny pores on plant leaves that regulate gas exchange, including plant defensive emissions and carbon dioxide, between the plant and the environment.

Specifically, the researchers studied the effects of a particular enzyme -- glucose oxidase (GOX) -- that occurs in the saliva of tomato fruitworm caterpillars (Helicoverpa zea) on plant stomata and plant defensive emissions, called herbivore-induced plant volatiles (HIPV).

"HIPVs are thought to help protect plants from insect herbivores by attracting natural enemies of those herbivores and by alerting neighboring plants to the presence of herbivores nearby," Felton said. "Consequently, stomatal closure has the potential to alter interactions across the entire plant community."

In their experiments, the researchers used CRISPR/Cas9, a technique for editing genomes, to produce caterpillars that lack the GOX enzyme. In separate glass chambers fitted with filter traps to collect HIPVs, they allowed the caterpillars with the non-functional enzyme, along with unmanipulated caterpillars, to feed on tomato, soybean and cotton plants for three hours. To examine the stomatal response to GOX, the team examined the plant leaves under a microscope and measured the size of the stomatal openings. Next, they extracted the volatile compounds from the filter traps and used gas chromatography, coupled with mass spectrometry, to identify and quantify the HIPVs.

"This study is the first to use CRISPR/Cas9-mediated gene editing to study the function of an insect salivary enzyme," said Po-An Lin, a graduate student in entomology at Penn State and the lead author of the paper. "Using pharmacological, molecular, and physiological approaches, we were able to show that this salivary enzyme plays a key role in insect-induced stomatal closure and likely the reduction of several important defensive emissions."

Indeed, the team -- comprising experts in molecular biology, chemical ecology, plant physiology and entomology -- found that GOX, secreted by the caterpillar onto leaves, causes stomatal closure in tomato plants within five minutes, and in both tomato and soybean plants for at least 48 hours. They also found that GOX inhibits the emission of several HIPVs during feeding, including (Z)-3-hexenol, (Z)-jasmone and (Z)-3-hexenyl acetate, which are important airborne signals in plant defenses. Interestingly, they did not find an effect of GOX on the cotton plants, which, the team said, suggests that the impacts of GOX on stomatal conductance is species dependent.

The team's results appeared in the Jan. 18 issue of New Phytologist.

Lin noted that the fact that tomato fruitworm caterpillars evolved a salivary enzyme that inhibits emissions of defensive volatiles in certain species suggests the importance of plant airborne defenses in the evolution of insect herbivores.

"Given the ubiquity of HIPVs in plants, it is likely that traits which influence HIPVs have evolved broadly among insect herbivores," he said.

Not only do these insects damage individual plants, but they also may render them less able to withstand climate change.

"Stomata are important organs of plants that not only detect and respond to environmental stressors, but also play a central role in plant growth," said Felton. "Because stomata play an important role in regulating leaf temperature and leaf water content, our findings suggest that the control of stomatal opening by an insect could impact the plant's response to elevated temperatures occurring with climate change and response to water deficiency."

When materials reach extremely small size scales, strange things begin to happen. One of those phenomena is the formation of mesocrystals.

Despite being composed of separate individual crystals, mesocrystals come together to form a larger, fused structure that behaves as a pure, single crystal. However, these processes happen at scales far too small for the human eye to see and their creation is extremely challenging to observe.

Because of these challenges, scientists had not been able to confirm exactly how mesocrystals form.

Now new research by a Pacific Northwest National Laboratory (PNNL)-led team used advanced transmission electron microscopy (TEM) techniques to see mesocrystals form in solution in real time. What they saw runs contrary to conventional wisdom and their insights could one day help scientists design materials for energy storage and understand how minerals in soil form.

Rather than individual crystals nucleating, the step that begins crystal formation, and then randomly aggregating into mesocrystals in two unrelated steps, the researchers observed that nucleation and attachment were closely coupled in forming these highly uniform structures. The researchers reported their work in the February 18, 2021 issue of Nature.

"Our findings identify an important new pathway of crystallization by particle attachment and resolve key questions about mesocrystal formation," said PNNL and University of Washington materials scientist Guomin Zhu. He was part of the research team led by Jim De Yoreo, PNNL materials scientist and co-director of the Northwest Institute for Materials Physics, Chemistry, and Technology. "We suspect this is a widespread phenomenon with significant implications both for the synthesis of designed nanomaterials and for understanding natural mineralization," Zhu added.

Seeing crystallization in real-time

The project took years to execute and required significant problem solving. For the microscopy experiments, the scientific team chose a model system that included hematite, an iron compound commonly found in the Earth's crust, and oxalate, a naturally abundant compound in soil.

They visualized the process using in situ TEM, which gives researchers the ability to see crystallization at the nanometer scale as it happens. They combined this real-time method with "freeze-and-look" TEM that enabled them to follow an individual crystal at different points during growth. Theoretical calculations helped complete the picture, allowing the PNNL team to piece together how the mesocrystals grew.

Researchers generally run most in situ TEM experiments at room temperature to simplify the experimental setup and minimize the potential for damaging the sensitive instrument, but mesocrystal formation rapid enough to observe occurs at around 80 °C.

"The additional equipment used to heat the samples made the experiments extremely challenging, but we knew the data would be key to understanding how the mesocrystals were forming," said Zhu.

Once heated, the new hematite nanocrystals make it easy for them to rapidly attach together, which leads, on average, to final mesocrystals of approximately the same size and shape.

Mesocrystals in nature

The chemical key to this rapid, reliable attachment is the oxalate molecules present in the solution. After the first few small crystals form, the oxalate additives help create a chemical gradient at the interface of the liquid and the growing crystal. More chemical components necessary for particle nucleation linger near the crystals, which dramatically increases the likelihood that new particles will form near existing ones.

While this crystal growth pathway was observed in controlled conditions at very small scales, it likely also occurs in natural systems, according to the researchers. Some mineral deposits, including an Australian hematite deposit, contain mesocrystals. Given the natural abundance of oxalate and the PNNL team's observation that hematite can become mesocrystals at temperatures as low as 40 °C, it seems plausible that this formation route occurs in nature.

Because mesocrystals are found throughout nature, the findings can be applied to understanding nutrient cycling in the environment, among other applications. Moreover, the route to creating near-uniform complex structures requires an understanding of how methods for forming such materials work and how to control them. Thus this work, supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, opens new possibilities to intentionally create mesocrystals or mesocrystal-like materials.

Although interest in studying prosocial behaviors among U.S. Latinx individuals has increased recently, there is still limited existing research with this population. Evidence shows that prosocial behaviors (actions intended to benefit others) are a marker of healthy social functioning and can both support positive development (such as academic achievement) and mitigate problematic outcomes (such as anxiety and depression). An important question is whether prosocial behavior is fostered by parents in ways that are specific to their cultural groups or through more universal aspects of parenting. A new longitudinal study in the United States examined relations among parenting, culture, and prosocial behaviors in U.S. Mexican youth.

The findings were published in a Child Development article written by researchers at the University of New Mexico, University of California at Irvine, Arizona State University, and University of Missouri.

The results point to the importance of both cultural practices and aspects of parenting seen across cultural groups, such as acceptance and harshness. They also underscore the importance of both fathers and mothers in supporting prosocial behavior.

Results showed that fathers' but not mothers' acceptance predicted youth's prosocial behaviors (helping others when asked, helping in emergency situations, and comforting others when upset).

Similarly, paternal but not maternal harshness predicted less helping in situations where there was no expectation of benefit from others, but also predicted more helping in front of others (perhaps when acknowledgement or rewards might be anticipated).

In addition, ethnic socialization practices by both mothers and fathers predicted more prosocial behaviors by fostering youth's ethnic identity and familism values (supporting the family emotionally, physically, and financially; having a sense of obligation; and incorporating the family as part of the self).

Both parents' ethnic socialization practices were important to youth sense of ethnic identity in 10th grade, but with maternal behavior showing a greater influence earlier in development (at 5th but not 7th grade) and paternal behavior later (in 7th but not 5th grade).

"Researchers have often emphasized the role of parenting in fostering youth's prosocial development," said Cara Streit assistant professor in the Department of Individual, Family, and Community Education at the University of New Mexico. "Our findings suggest the need for integrative, culturally-sensitive theories that focus on the relations between culture-related mechanisms (such as ethnic socialization and familism), and parenting practices that are more universal (such as acceptance and harshness) to successfully promote positive youth development among U.S. Latinx youth."

Participants were recruited from diverse communities in a metropolitan area of the U.S. Southwest and included 462 Mexican adolescents (48 percent female) and their mothers and fathers. The families participated in four waves of data collection at the 5th, 7th, 10th, and 12th grades and were assessed through the following measures:

Acceptance and harsh parenting (5th and 7th grade): parents were asked to review statements such as "You made [child] feel better after talking over his/her worries with him/her" or "You lost your temper with [child] when s/he didn't help around the house" using a scale ranging from "almost never" or to "almost always or always."

Parental ethnic cultural socialization (5th and 7th grade): using a scale ranging from "almost never" to "a lot of the time (frequently)," parents were asked to review statements such as "How often do you: tell your child to be proud of his/her Mexican background."

Ethnic identity (7th grade): adolescents were asked to review statements such as "You have attended events that have helped you learn more about your Mexican/Mexican American background" using a scale ranging from "not at all true" to "
very true."

Familism values (10th grade): adolescents were asked to review statements such as "A person should share their home with relatives if they need a place to stay" using a scale ranging from "not at all" to "strongly agree."

Prosocial behaviors (12th grade): using a scale ranging from "does not describe me well at all" to "describes me greatly," adolescents reported their prosocial behaviors by reviewing statements such as "You never wait to help others when they ask for it." The study separated out different types of prosocial behavior, such as helping in emergency situations, comforting others when upset, and helping others when there is no expectation of benefit to self.

"Family support programs can best promote positive youth development among U.S. Latinx youth if they include both fathers and mothers and incorporate a focus on ethnic heritage, ethnic identity, and traditional cultural values," said Gustavo Carlo, professor in the School of Education at the University of California, Irvine.

The authors recognize that the study relies entirely on participant self-reports. They also recommend that future studies should consider bidirectional and fully reciprocal study designs to allow for more stringent tests of direction of effects as well as a sample that includes more recent emigrants.

Children raised in neighborhoods with low socio-economic status are at risk for low academic achievement. A new longitudinal study followed young children from such neighborhoods from birth until age seven to explore whether children's capacity to act kindly or generously towards others (prosocial behavior) - including peers, teachers, and family - is linked to their ability to perform well in school. The study showed that prosocial behavior may mitigate academic risk across early childhood.

The findings were published in a Child Development article written by researchers at Stanford University and the University of Leeds, and the Bradford Institute for Health Research.

"Identifying factors that can help children achieve academic success is a crucial step to informing interventions that may reduce educational disparities between children," said Emma Armstrong-Carter, doctoral candidate in the Stanford University Graduate School of Education. "This research turns our attention to the connections between social and academic outcomes for children. It suggests that supporting positive social behavior may be one way to foster children's academic success where the odds are against them."

The study included 1,175 children and their families from Bradford, England, who were predominantly of White European or South Asian ancestries. Children were followed from birth until the age of seven with measurements taken at four times from 2007 to 2010.

The researchers used the following methods:

Governmental indices of neighborhood-level socioeconomic status,

Teacher observations of prosocial behaviors (e.g., "This child is considerate of other people's feelings," or "This child is helpful if someone is hurt"), at ages 4-5

Direct assessments of three academic outcomes: teachers' observations of children's progress towards early learning goals at ages 4-5 years, teachers' assessment of phonic skills (ability to correlate sounds with letters or groups of letters in an alphabetic writing system) at ages 5-6 years, and academic performance assessed on a standardized school-based assessment, including math, reading and science, at ages 6-7.

Low neighborhood socioeconomic status was associated with poor academic outcomes only for children who displayed low levels of prosocial behavior and not among children who displayed high levels of prosocial behavior. This pattern was consistent across the three measures of educational progress taken from ages 4 to 7. The authors note that stronger prosocial behavior may act as a protective factor for educational outcomes in a number of ways. For example, children who are perceived as more helpful may be more likely to be liked by their teachers and receive more positive attention compared to their peers who tend to help less. When helping others, children may also have opportunities for cognitive stimulation by practicing skills such as taking the perspective of others and communicating with them.

"Our research suggests that fostering prosocial behavior during early childhood may be one way to protect against academic risk for those living in low- income neighborhoods," said Armstrong-Carter. "It is possible that teachers, parents and mentors may be able to help children achieve academic success by modeling, teaching, and fostering the development of helping behaviors."

The authors recognize that they were unable to measure the specific relationships between parents and teachers, and experiences when helping peers. The authors also acknowledge the need to replicate this study in other samples outside of Bradford, England, to see if the results are generalizable across different geographic and cultural contexts. This study was correlational, so future research should explore whether prosocial behavior causes children to be protected from academic risk that occurs in neighborhoods with low socioeconomic status; for example, by randomized interventions designed to increase children's prosocial behavior.

A study recently completed in Europe and North America indicates that the composition of wintering and breeding bird communities changes in line with global warming. However, wintering bird communities are considerably faster at tracking the changing climate compared to breeding communities.

Climate change is driving species' distribution towards the poles and mountaintops, resulting in changes to bird communities. As a considerable share of birds are migratory species, with the distance they travel varying by species, the rate of change in bird communities is different in the breeding season and in the winter. A new Finnish-led study demonstrates for the first time that changes in bird communities are significantly faster in the winter than in the breeding season.

"Climate change is reshaping bird communities so that abundance of southern species increase, while the abundance of northern species is reduced," says Senior curator Aleksi Lehikoinen from the Finnish Museum of Natural History Luomus, which is part of the University of Helsinki.

The faster change of bird communities in the winter is most likely results from the birds being less sedentary in their wintering areas than in their breeding areas. Some species are capable of migrating also in mid-winter, if the weather gets colder. In fact, a rise in temperature increased the annual rate of change for wintering bird communities. During the breeding season, individual birds are bound to a specific environment for several months, preventing them from migrating in the middle of breeding even if the weather changes.

"In Finland, wintering bird communities in particular have changed due to the rapid increase in abundance of southern species, such as the tufted duck, the blackbird and the goldfinch. As winters become warmer faster than summers, our winter bird communities will continue to change rapidly also in the future," Lehikoinen explains.

The study examined changes in bird communities in eight countries in Europe as well as in the United States and Canada since the 1980s. While the dataset encompasses over 1,200 bird species and a broad range of bird communities, the results were largely similar for both continents.

"Overall, the study included observations of almost three billion birds. Without keen birdwatchers contributing on a voluntary basis, collecting such a dataset would be impossible," Lehikoinen says, offering praise.

Effective governance and investment decisions need to be informed by reliable data, not only about where groundwater exists, but also the rate at which groundwater is replenished. For the first time using ground measurements, a recent study has quantified groundwater recharge rates across the whole of Africa - averaged over a fifty-year period - which will help to identify the sustainability of water resources for African nations.

The study, led by the British Geological Survey and involving an international team from the UK, South Africa, France, Nigeria, and America, developed a dataset of 134 existing recharge studies for Africa for the period from 1970 to 2019 to create a valuable resource providing an overview of the recharge pattern across the continent. Long-term average recharge values were evaluated, and each data source was critically reviewed. The recharge data were then analysed using a linear model, to map across Africa. The resulting dataset provides the first such ground-based approximation of the renewability of groundwater storage in Africa. The results have been published today in the IOP Publishing journal Environmental Research Letters, and the maps and data are freely available online for governments, researchers and NGOs to use.

Lead author of the paper, BGS Hydrogeologist Professor Alan MacDonald explains the need for this research: "In many parts of the world, rapid increases in groundwater pumping have led to unsustainable conditions, characterised by falling water tables and problems with water quality. Consequently, quantifying the scale of groundwater recharge is critical to characterise the resilience of groundwater supplies to both increased use and climate change."

Estimating groundwater recharge is difficult, as the authors outline: "There is no one method that can directly quantify the volume of rainwater that reaches the water-table, so the focus of the research has been to combine many different methods, each appropriate to the different environments in Africa and then aggregate them using statistical techniques."

The results show that at a continental scale, long-term average rainfall predicts groundwater recharge but there are differences at a local scale due to soil and landcover and from year to year, due to the variability in the intensity of rainfall. Approximately 2% of all groundwater storage is replenished in Africa every decade and recharge can occur even in semi-arid areas. This research turns around some widely held perceptions and provides hope for the continent as it rapidly grows in population and infrastructure development.

The new groundwater maps show an interesting pattern for Africa. Most African countries with little groundwater storage (such as Liberia, Guinea and Burundi) have high rainfall and therefore regular recharge and, conversely, many north African countries with negligible rainfall, usually considered as water insecure, have considerable groundwater storage.

It is hoped that the groundwater recharge maps will help show where there is potential to sustainably develop more groundwater and where it could be wise to invest effort in monitoring groundwater that may be at risk of depletion or susceptible to drought. The research could also help countries locate where new more detailed studies should be focused and how to design these studies, identifying which methods may be the best to use.

Professor MacDonald adds: "The maps of groundwater recharge and storage help uncover the hidden water security situation in Africa. For several countries with high groundwater storage, particularly in North Africa, groundwater pumping can increase current water security but, ultimately, at the expense of future generations. Countries with low groundwater storage are common in Africa because of the geology - however for most of these countries this groundwater storage is replenished regularly and is a reliable source of water. Only if people pump out too much (for example for large scale irrigation) will the groundwater be in danger of drying up during droughts."

Professor Seifu Kebede from the University of KwaZulu Natal, a co-author of the paper adds: "This effort brought together extensive African knowledge with expertise from other countries to provide information to sustainably develop water resources and overcome some of the most pressing issues countries often face, such as drought, deprivation, and starvation."

The mitochondrial ribosome is an intricate machine that translates the organellar genome into functional proteins. The formation of the mitochondrial ribosome is a hierarchical process involving dozens of different components. The newly published cryo-EM study by Tobiasson et al in the EMBO Journal characterized a key step in this process.

A complex of 2.2 MegaDalton representing a rare state of assembly of the large subunit was isolated from a model organism Trypanosoma brucei. Since the state was identified in only 3.5 % of the complexes, five cryo-EM datasets had to be collected at the SciLifeLab facility and ESRF in Grenoble and combined together.

The resulting structure revealed that the assembly factors form a network that spans a distance of 18 nanometres shielding the sensitive ribosomal core that is made of less-stable nucleic acids. The network is designed to connect all the functional regions on the mitoribosomal large subunit for their correlated maturation.

A phylogenetic analysis further showed that most of the newly identified assembly factors also exist in human, and therefore the derived characteristics represent general principles. However, an unexpected finding is that some of those factors appeared to loose their activity. Despite being deactivated, they still contribute as structural mediators for a stabilisation of the functionally active partners on the mitoribosomal core. The preservation of the deactivated factors implies a mechanism of the evolutionary conservation of the sequential assembly.

The work showcases how the structural approach of studying stabilized intermediates is instrumental for understanding dynamic macromolecular processes that can be extrapolated to human counterpart metabolic pathways and provide an evolutionary insight.