A study published the week of July 5 in the Proceedings of the National Academy of Sciences led by Michael Moore at Washington University in St. Louis finds that dragonfly males have consistently evolved less breeding coloration in regions with hotter climates. "Our study shows that the wing pigmentation of dragonfly males evolves so consistently in response to the climate that it's among the most predictable evolutionary responses ever observed for a mating-related trait," said Moore, who is a postdoctoral fellow with the Living Earth Collaborative at Washington University. "This work reveals that mating-related traits can be just as important to how organisms ...

Scientists recently made news by using fossil shark scales to reconstruct shark communities from millions of years ago. At the same time, an international team of researchers led by UC Santa Barbara ecologist Erin Dillon applied the technique to the more recent past. Human activities have caused shark populations to plummet worldwide since records began in the mid-20th century. However, the scientists were concerned that these baseline data may, themselves, reflect shark communities that had already experienced significant declines. Dillon compared the abundance and variety of shark scales from a Panamanian coral reef 7,000 years ago to those in reef sediments ...

A vast seabird colony on Ascension Island creates a "halo" in which fewer fish live, new research shows. Ascension, a UK Overseas Territory, is home to tens of thousands of seabirds - of various species - whose prey incudes flying fish. The new study, by the University of Exeter and the Ascension Island Government, finds reduced flying fish numbers up to 150km (more than 90 miles) from the island - which could only be explained by the foraging of seabirds. The findings - which provide rare evidence for a long-standing theory first proposed at Ascension - show how food-limited seabird populations naturally are, and why they are often so sensitive to competition with human fishers. ...

Nanomaterials found in consumer and health-care products can pass from the bloodstream to the brain side of a blood-brain barrier model with varying ease depending on their shape - creating potential neurological impacts that could be both positive and negative, a new study reveals. Scientists found that metal-based nanomaterials such as silver and zinc oxide can cross an in vitro model of the 'blood brain barrier' (BBB) as both particles and dissolved ions - adversely affecting the health of astrocyte cells, which control neurological responses. But the researchers also believe that their discovery will help to design safer nanomaterials and could open ...

Like female voles, connections between oxytocin neurons in the hypothalamus and dopamine neurons in reward areas drive parental behaviors in male voles, according to new research published in JNeurosci. Motherhood receives most of the attention in the research world, yet in 5% of mammals -- including humans -- fathers provide care, too. The "love hormone" oxytocin plays a role in paternal care, but the exact neural pathways underlying the behavior were not known. He et al. measured the neural activity of vole fathers while they interacted with their offspring. Oxytocin neurons connecting the hypothalamus to a reward area fired when the fathers cared for their offspring. ...

The psychedelic drug psilocybin, a naturally occurring compound found in some mushrooms, has been studied as a potential treatment for depression for years. But exactly how it works in the brain and how long beneficial results might last is still unclear. In a new study, Yale researchers show that a single dose of psilocybin given to mice prompted an immediate and long-lasting increase in connections between neurons. The findings are published July 5 in the journal Neuron. "We not only saw a 10% increase in the number of neuronal connections, but also they were on average about 10% larger, so the connections were stronger as well," said Yale's Alex Kwan, associate professor of psychiatry and of neuroscience and senior author of the paper. Previous ...

A new collaborative research led by researchers from the National Institute for Environmental Studies, Potsdam Institute for Climate Impact Research, Ritsumeikan University, and Kyoto University found that although unlimited irrigation could increase global BECCS potential (via the increase of bioenergy production) by 60-71% by the end of this century, sustainably constrained irrigation would increase it by only 5-6%. The study has been published in Nature Sustainability on July 5. Bioenergy with carbon capture and storage (BECCS) is a process of extracting bioenergy from biomass, ...

"The number of black holes is roughly three times larger than expected from the number of stars in the cluster, and it means that more than 20% of the total cluster mass is made up of black holes. They each have a mass of about 20 times the mass of the Sun, and they formed in supernova explosions at the end of the lives of massive stars, when the cluster was still very young" says Prof Mark Gieles, from the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and lead author of the paper. Tidal streams are streams of stars that were ejected from disrupting ...

Land plants - plants that live primarily in terrestrial habitats and form vegetation on earth - are anchored to the ground through their roots, and their performance depends on both the belowground soil conditions and the aboveground climate. Plants utilize sunlight to grow through the process of photosynthesis where light energy is converted to chemical energy in chloroplasts, the powerhouses of plant cells. Therefore, the amount and quality of light perceived by chloroplasts through light absorbing pigments, such as chlorophyll, is a defining factor in plant growth and health. ...

MADISON, Wis. -- About 100 additional wolves died over the winter in Wisconsin as a result of the delisting of grey wolves under the Endangered Species Act, alongside the 218 wolves killed by licensed hunters during Wisconsin's first public wolf hunt, according to new research. The combined loss of 313 to 323 wolves represents a decline in the state's wolf population of between 27% and 33% between April 2020 and April 2021. Researchers estimate that a majority of these additional, uncounted deaths are due to something called cryptic poaching, where poachers hide evidence of illegal killings. The findings are the first estimate of Wisconsin's wolf population since the public hunt in February, which ended early after hunters ...

The theory that modern society is too clean, leading to defective immune systems in children, should be swept under the carpet, according to a new study by researchers at UCL and the London School of Hygiene & Tropical Medicine. In medicine, the 'hygiene hypothesis' states that early childhood exposure to particular microorganisms protects against allergic diseases by contributing to the development of the immune system. However, there is a pervading view (public narrative) that Western 21st century society is too hygienic, which means toddlers and children are likely to be less exposed to germs in early life and so become less resistant to allergies. In this paper, published in the Journal of Allergy and Clinical Immunology, researchers point to four significant reasons which, ...

Research published today has demonstrated the viability of 3D-printed tissue scaffolds that harmlessly degrade while promoting tissue regeneration following implantation. The scaffolds showed highly promising tissue-healing performance, including the ability to support cell migration, the 'ingrowth' of tissues, and revascularisation (blood vessel growth). Professor Andrew Dove, from the University of Birmingham's School of Chemistry, led the research group and is the lead author on the paper published in Nature Communications, which characterises the physical properties of the scaffolds, and explains how their 'shape memory' is key to promoting tissue regeneration. ...

Flies have discriminating taste. Like a gourmet perusing a menu, they spend much of their time seeking sweet nutritious calories and avoiding bitter, potentially toxic food. But what happens in their brains when they make these food choices? Yale researchers discovered an interesting way to find out. They tricked them. In a study that could also help illuminate how people make food choices, the researchers gave hungry fruit flies the choice between sweet, nutritious food laced with bitter quinine and a less sweet, but not bitter, food containing fewer calories. Then, using neuroimaging, they tracked neural activity in their brains as they made these tough choices. So which won? Calories or better taste? "It depends on how hungry they are," said Michael Nitabach, professor of ...

Researchers at Uppsala University have discovered lymph node-like structures close to the tumour in brain cancer patients, where immune cells can be activated to attack the tumour. They also found that immunotherapy enhanced the formation of these structures in a mouse model. This discovery suggests new opportunities to regulate the anti-tumour response of the immune system. Glioma is a deadly brain tumour with a dismal prognosis. One reason why brain tumours are very hard to treat is that our immune system, which is designed to detect and destroy foreign ...

Although most Canadians die from predictable causes and have health needs that can be met at home, only 20% of people receive a physician home visit in their last year of life. To help understand the changing care needs of older adults as they age and when they might be nearing the end of their lives, a team of researchers developed the Risk Evaluation for Support: Predictions for Elder-Life in the Community Tool (RESPECT). The calculator, which predicts death within 6 months, is based on data from more than 491 000 community-dwelling older adults who used home care in the 6-year period between 2007 and 2013. "The RESPECT calculator allows families and their loved ...

Oncotarget published "Carcinoma cells that have undergone an epithelial-mesenchymal transition differentiate into endothelial cells and contribute to tumor growth" which reported that the authors investigated whether EMT can confer endothelial attributes upon carcinoma cells, augmenting tumor growth and vascularization. Hypoxic regions, demarcated by HIF-1α staining, exhibited focal areas of E-cadherin loss and elevated levels of vimentin and the EMT-mediator FOXC2. Implantation of MCF-7 cells, co-mixed with human mammary epithelial cells overexpressing the EMT-inducer Snail, markedly ...

Oncotarget published "Perioperative changes in the plasma metabolome of patients receiving general anesthesia for pancreatic cancer surgery" which reported that little is known about the impact of anesthesia on the plasma metabolome, although many metabolites have been shown to modulate the function of various immune cells, making it particularly interesting in the context of oncological surgery. In this study longitudinal dynamics in the plasma metabolome during general anesthesia in patients undergoing pancreatic surgery were analyzed. Prospective, observational study with 10 patients diagnosed with pancreatic malignancy and subjected to elective resection surgery under general anesthesia. Plasma metabolites were quantified at ...

Oncotarget published "Genome wide DNA methylation landscape reveals glioblastoma's influence on epigenetic changes in tumor infiltrating CD4+ T cells" which reported that whole-genome bisulfite sequencing of tumor infiltrating and blood CD4 T-cell from GBM patients showed 13571 differentially methylated regions and a distinct methylation pattern of methylation of tumor infiltrating CD4 T-cells with significant inter-patient variability. The methylation changes also resulted in transcriptomic changes with 341 differentially expressed genes in CD4 tumor infiltrating T-cells compared to blood. Analysis of specific genes involved in CD4 differentiation and function revealed differential methylation status of TBX21, GATA3, RORC, FOXP3, IL10 and ...

Inadequate exposure to UVB light from the sun may be associated with an increased risk of colorectal cancer, particularly in older age groups, according to a study using data on 186 countries, published in the open access journal BMC Public Health. Researchers at the University of California San Diego, USA investigated possible associations between global levels of UVB light in 2017 and rates of colorectal cancer for different countries and age groups in 2018. The authors found that lower UVB exposure was significantly correlated with higher rates of colorectal cancer across all ...

Why are gold deposits found at all? Gold is famously unreactive, and there seems to be little reason why gold should be concentrated, rather than uniformly scattered throughout the Earth's crust. Now an international group of geochemists have discovered why gold is concentrated alongside arsenic, explaining the formation of most gold deposits. This may also explain why many gold miners and others have been at risk from arsenic poisoning. This work is presented at the Goldschmidt conference, after recent publication*. Gold has been prized for millennia, for its purity and stability. It's also rare enough to retain its value - the World Gold Council estimates that all the gold ever mined in the world would fit into a 20x20x20-meter cube. It is valued for its beauty, but also because it ...

Scientists have reconstructed the Eastern Mediterranean silver trade, over a period including the traditional dates of the Trojan War, the founding of Rome, and the destruction of Solomon's Temple in Jerusalem. The team of French, Israeli and Australian scientists and numismatists found geochemical evidence for pre-coinage silver trade continuing throughout the Mediterranean during the Late Bronze and Iron Age periods, with the supply slowing only occasionally. Silver was sourced from the whole north-eastern Mediterranean, and as far away as the Iberian ...

Scientists have found an unexplained cache of fossilised shark teeth in an area where there should be none - in a 2900 year old site in the City of David in Jerusalem. This is at least 80 km from where these fossils would be expected to be found. There is no conclusive proof of why the cache was assembled, but it may be that the 80 million-year-old teeth were part of a collection, dating from just after the death of King Solomon*. The same team has now unearthed similar unexplained finds in other parts of ancient Judea. Presenting the work at the Goldschmidt Conference, lead researcher, Dr. Thomas Tuetken (University of Mainz, Institute of Geosciences) said: "These fossils are not in their original setting, so they have been moved. They were probably valuable to someone; ...

Tokyo, Japan - Researchers from Tokyo Metropolitan University have used high power impulse magnetron scattering (HiPIMS) to create thin films of tungsten with unprecedentedly low levels of film stress. By optimizing the timing of a "substrate bias pulse" with microsecond precision, they minimized impurities and defects to form crystalline films with stresses as low as 0.03 GPa, similar to those achieved through annealing. Their work promises efficient pathways for creating metallic films for the electronics industry. Modern electronics relies on the intricate, nanoscale deposition of thin metallic films onto surfaces. This is easier said than done; unless done right, "film stresses" arising from the microscopic internal structure of the film ...

In recent years, immunotherapy has revolutionised the field of cancer treatment. However, inflammatory reactions in healthy tissues frequently trigger side effects that can be serious and lead to the permanent discontinuation of treatment. This toxicity is still poorly understood and is a major obstacle to the use of immunotherapy. Scientists from the University of Geneva (UNIGE), Switzerland, and Harvard Medical School, United States, have succeeded in establishing the differences between deleterious immune reactions and those targeting tumour cells that are sought after. It appears that while the immune mechanisms are similar, the cell ...

It is the membrane of cancer cells that is at the focus of the new research now showing a completely new way in which cancer cells can repair the damage that can otherwise kill them. In both normal cells and cancer cells, the cell membrane acts as the skin of the cells. And damage to the membrane can be life threatening. The interior of cells is fluid, and if a hole is made in the membrane, the cell simply floats out and dies - a bit like a hole in a water balloon. Therefore, damage to the cell membrane must be repaired quickly, and now research from a team of Danish researchers shows that cancer cells use a ...