Modelling extreme magnetic fields and temperature variation on distant stars


IMAGE: The maps show the heat distribution. The bue regions are cooler – and the yellow regions are hotter.

It describes data taken from the following magentars: 4U 0142+61, 1E 1547.0-5408, XTE…
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Credit: University of Leeds

New research is helping to explain one of the big questions that has perplexed astrophysicists for the past 30 years – what causes the changing brightness of distant stars called magnetars.

Magnetars were formed from stellar explosions or supernovae and they have extremely strong magnetic fields, estimated to be around 100 million, million times greater than the magnetic field found on earth.

The magnetic field generates intense heat and x-rays. It is so strong it also affects the physical properties of matter, most notably the way that heat is conducted through the crust of the star and across its surface, creating the variations in brightness across the star which has puzzled

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Cortex-wide variation of neuronal cellular energy levels depending on the sleep-wake states — ScienceDaily

It is assumed that the brain has homeostatic mechanisms to prevent the depletion of cellular energy, required for all cellular activities. For example, the blood flow increases, and oxygen and glucose are actively delivered in the brain region in which neural firing activity occurs. Besides, the cerebral blood flow and glucose uptake into the cells fluctuate accompanying the variations of cellular activities in the brain across the sleep-wake states of animals. Under these brain energy homeostatic mechanisms, it is assumed that the cellular energy status in the brain could be maintained constant in all physiological conditions including across the sleep-wake states of animals. However, this has not been experimentally proven.

To investigate whether the cellular energy status in the brain of living animals is always constant or variated, the researchers measured the neuronal intracellular concentration of adenosine 5′-triphosphate (ATP), the major cellular energy metabolite, using a fluorescent sensor in the

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Polar ice, atmospheric water vapor biggest drivers of variation among climate models — ScienceDaily

A Florida State University researcher is part of a team that has found varying projections on global warming trends put forth by climate change scientists can be explained by differing models’ predictions regarding ice loss and atmospheric water vapor.

The work will help climate scientists reconcile various models to improve their accuracy, said Florida State University Meteorology Professor Ming Cai, one of the authors of the study published in Nature Communications .

Climate scientists agree that the Earth’s surface temperature is warming, but the details of exactly where and by how much are less clear. A worst-case climate change scenario (known as the “Representative Concentration Pathway 8.5”) predicted a likely increase in average global temperatures of about 2.6 degrees Celsius to 4.8 degrees Celsius (or about 4.7 degrees Fahrenheit to 8.6 degrees Fahrenheit) by 2100.

“This uncertainty limits our ability to foresee the severity of the global warming impacts on

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Variation in genes associated with viral entry of SARS-CoV-2 unlikely to influence COVID-19 morbidity and mortality, study finds — ScienceDaily

A comprehensive search of genetic variation databases has revealed no significant differences across populations and ethnic groups in seven genes associated with viral entry of SARS-CoV-2.

African Americans and Latinos in the United States and ethnic minorities in the United Kingdom are disproportionately affected by COVID-19. They are more likely to develop severe symptoms and also show significantly higher mortality compared with other regional and ethnic groups.

To investigate if this disparity could be caused by genetic variation, a team of three researchers — including Assistant Professor Ji-Won Lee of Hokkaido University’s Graduate School of Dental Medicine — surveyed publicly available databases of genomic variants, including gnomAD, the Korean Reference Genome Database, TogoVar (a Japanese genetic variation database) and the 1000 Genomes Project. They studied variants across multiple regional and ethnic groups in seven genes known to play roles in viral entry into host cells and recognition of viral RNA

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