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90 articles from PhysOrg

Research leads to better modeling of hypersonic flow

Hypersonic flight is conventionally referred to as the ability to fly at speeds significantly faster than the speed of sound and presents an extraordinary set of technical challenges. As an example, when a space capsule re-enters Earth's atmosphere, it reaches hypersonic speeds—more than five times the speed of sound—and generates temperatures over 4,000 degrees Fahrenheit on its exterior...

Leaf microbiomes are a neighborhood affair in northern forests

Forest leaves are teeming with bacterial life—but despite the vast extent of bacteria-covered foliage across the world, this habitat, known as the phyllosphere, remains full of mysteries. How do bacteria spread from tree to tree? Do certain types of bacteria only live on certain types of trees?

Tree lifespan decline in forests could neutralize part of rise in net carbon uptake

Accelerating tree growth in recent years has been accompanied by a reduction in tree lifespan, which could eventually neutralize part of the increase in net uptake of carbon dioxide (CO2). This trade-off between tree growth and life expectancy applies to forests worldwide, including in the Amazon and other tropical regions, as well as temperate regions and the Arctic.

How proteins find their place in the cell

Over a quarter of all proteins in a cell are found in the membrane, where they perform vital functions. To fulfill these roles, membrane proteins must be reliably transported from their site of production in the cell to their destination and correctly inserted into the target membrane. Researchers from the Heidelberg University Biochemistry Center (BZH) have succeeded in determining the...

Red Sea turtle hatchlings are feeling the heat

Analyses by KAUST researchers of sand temperatures at marine turtle nesting sites around the Red Sea indicate that turtle hatchlings born in the region could now be predominantly female. These findings hold significant implications for the survival of marine turtle species as temperature increases take hold, driven by anthropogenic climate change.

Researchers confront optics and data-transfer challenges with 3D-printed lens

Researchers have developed new 3-D-printed microlenses with adjustable refractive indices—a property that gives them highly specialized light-focusing abilities. This advancement is poised to improve imaging, computing and communications by significantly increasing the data-routing capability of computer chips and other optical systems, the researchers said.

How plants compete for underground real estate affects climate change and food production

You might have observed plants competing for sunlight—the way they stretch upwards and outwards to block each other's access to the sun's rays—but out of sight, another type of competition is happening underground. In the same way that you might change the way you forage for free snacks in the break room when your colleagues are present, plants change their use of underground resources when...

3-D protein modeling suggests why COVID-19 infects some animals, but not others

Some animals are more susceptible to COVID-19 infection than others, and new research suggests this may be due to distinctive structural features of a protein found on the surface of animal cells. João Rodrigues of Stanford University, California, and colleagues present these findings in the open-access journal PLOS Computational Biology.

Physicists capture the sound of a 'perfect' fluid

For some, the sound of a "perfect flow" might be the gentle lapping of a forest brook or perhaps the tinkling of water poured from a pitcher. For physicists, a perfect flow is more specific, referring to a fluid that flows with the smallest amount of friction, or viscosity, allowed by the laws of quantum mechanics. Such perfectly fluid behavior is rare in nature, but it is thought to occur in the...

Mapping quantum structures with light to unlock their capabilities

A new tool that uses light to map out the electronic structures of crystals could reveal the capabilities of emerging quantum materials and pave the way for advanced energy technologies and quantum computers, according to researchers at the University of Michigan, University of Regensburg and University of Marburg.

How hot is too hot for life deep below the ocean floor?

At what depth beneath the seabed does it become so hot that microbial life is no longer possible? This question is the focus of a close scientific cooperative effort between the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) and MARUM—Center for Marine Environmental Sciences at the University of Bremen. An expedition by the drilling program IODP (International Ocean Discovery...

Natural selection plays major role in an organism's capacity to evolve and adapt

Everywhere we look in the natural world, there's evidence of natural selection: the resin armor of a lodgepole pine cone evolved to defend against seed-hungry birds and squirrels; the long neck of a giraffe was evolutionarily favored for reaching high vegetation that the competition can't touch. We know that natural selection shapes how animals and plants evolve and adapt. But does natural...

Shuttering fossil fuel power plants may cost less than expected

Decarbonizing U.S. electricity production will require both construction of renewable energy sources and retirement of power plants now operated by fossil fuels. A generator-level model described in the December 4 issue of the journal Science suggests that most fossil fuel power plants could complete normal lifespans and still close by 2035 because so many facilities are nearing the end of their...