Scientists discover a motif that guides assembly of the algal pyrenoid — ScienceDaily

The next time you visit a lake or the seashore, take a deep breath. As you exhale, take a moment to be thankful for the little things: specifically, for the microscopic, single-celled algae in the soil and waters all around you that are extracting the carbon dioxide you just exhaled and incorporating it into sugars that will eventually be used by every other organism in the biosphere. About 30% of this activity, globally, is carried out by a specialized structure in algae called the pyrenoid.

To visualize a pyrenoid, think of a pomegranate. The pyrenoid contains kernels of Rubisco, the enzyme that carries out the molecular work of incorporating carbon dioxide into sugars. These kernels are embedded in a supportive flesh, or matrix, of other proteins, that is itself surrounded by an outer shell made of starch. The fruit is a bit worm-eaten; it is riddled with fingerlike channels —

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Scientists solve the mystery behind an enigmatic organelle, the pyrenoid — ScienceDaily

Carbon is one of the main building blocks for life on Earth. It’s abundant in our planet’s atmosphere, where it’s found in the form of carbon dioxide. Carbon makes its way into Earthlings’ bodies mainly through the process of photosynthesis, which incorporates carbon dioxide into sugars that serve as components for important biomolecules and fuel the global food chain. About a third of this process globally is carried out by single-celled algae that live in the oceans (most of the rest is done by plants).

The enzyme that performs the first step of the reaction to assimilate carbon dioxide into sugars is a bulky protein called Rubisco assembled from eight identical small subunits and eight identical large subunits arranged together symmetrically. All the parts of this assembly, which is called a holoenzyme, work in concert to perform Rubisco’s enzymatic duty. Rubisco’s rate of activity — and by extension, the rate

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How Megalodon Sharks Grew Up to Become Apex Predators of the Sea, According to Scientists

Researchers have uncovered evidence to suggest that the largest sharks to ever roam the seas commonly raised their young in nursery areas where juveniles could grow up in a safe environment.

The scientists identified five potential megalodon nurseries—one off the eastern coast of Spain, two in the United States and two in Panama—in a study published in the Royal Society journal Biology Letters.

Megalodon (Otodus megalodon) is an extinct shark species that lived between 23 million and 3.6 million years ago.

The shark is considered to be one of the largest and most powerful predators ever to have lived on Earth, with some estimates suggesting that it could have grown up to around 60 feet in length.

Despite its gigantic size, young megalodon would have been vulnerable to attacks by other predators.

In order to overcome this problem, the sharks gave birth to their young in shallow,

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Scientists call for decade of concerted effort to enhance understanding of the deep seas

Scientists call for decade of concerted effort to enhance understanding of the deep seas
A close-up image of a bamboo coral called Acanella arbuscula taken from ~1000m deep in the North East Atlantic Credit: NERC funded Deep Links Project (University of Plymouth, Oxford University, JNCC, BGS)

The deep seas—vast expanses of water and seabed hidden more than 200 meters below the ocean surface to depths up to 11,000 meters—are recognized globally as an important frontier of science and discovery.


But despite the fact they account for around 60% of Earth’s surface area, large areas remain completely unexplored, yet the habitats they support impact on the health of the entire planet.

Now an international team of scientists, spanning 45 institutions in 17 countries, has called for a dedicated decade-long program of research to greatly advance discovery in these remote regions.

The program—which scientists have named Challenger 150—will coincide with the United Nations Decade of Ocean Science for Sustainable Development, which runs from 2021-2030.

Challenger 150

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For the first time, scientists detect the ghostly signal that reveals the engine of the universe

In research published Wednesday in the journal Nature, scientists reported that they’ve made the first detection of almost-ethereal particles called neutrinos that can be traced to carbon-nitrogen-oxygen fusion, known as the CNO cycle, inside the sun.

It’s a landmark finding that confirms theoretical predictions from the 1930s, and it’s being hailed as one of the greatest discoveries in physics of the new millenium.

“It’s really a breakthrough for solar and stellar physics,” said Gioacchino Ranucci of the Italian National Institute for Nuclear Physics (INFN), one of the researchers on the project since it began in 1990.

The scientists used the ultrasensitive Borexino detector at the INFN’s Gran Sasso particle physics laboratory in central Italy – the largest underground research center in the world, deep beneath the Apennine Mountains, about 65 miles northeast of Rome.

The detection caps off decades of study of the sun’s neutrinos by the Borexino project, and

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Russian scientists improve 3D printing technology for aerospace composites using oil waste

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IMAGE: Aviation parts printed on a 3D printer from new metal powders
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Credit: Sergey Gnuskov/NUST MISIS

Scientists from NUST MISIS have improved the technology of 3D printing from aluminum, having achieved an increase in the hardness of products by 1,5 times. The nanocarbon additive to aluminum powder, which they have developed, obtained from the products of processing associated petroleum gas, will improve the quality of 3D printed aerospace composites. The research results are published in the international scientific journal Composites Communications

Today, the main field of application for aluminum 3D printing is the creation of high-tech parts for the aviation and space industries. The presence of even the slightest defects in printed structures is critical to the safety of the technology being created. According to NUST MISIS scientists, the main risk of such defects is the high porosity of the material, caused, among other reasons, by the qualities

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Scientists Are Becoming More Politically Engaged

For many, the 2016 presidential election represented an existential threat to science and jolted large segments of the research workforce into street protest mode. More recently, the COVID-19 pandemic has thrust scientists into global prominence, while the Black Lives Matter uprising has forced a reckoning with science’s problematic past and present. In many ways, science itself was on the ballot this Election Day. Prominent scientific journals endorsed Democratic presidential candidate Joe Biden, scientific societies issued statements in the wake of the George Floyd killing, and thousands of scientists went on strike in solidarity with Black Lives Matter.


With scientists and scientific organizations now more politically engaged than at any time since the Vietnam War, we sought to understand the scope and focus of their political engagement. Before the November 3 elections, we surveyed more than 1,500 researchers belonging to the Union of Concerned Scientists Science Network (UCSSN)—a multidisciplinary network of

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AI helps scientists understand brain activity behind thoughts — ScienceDaily

A team led by researchers at Baylor College of Medicine and Rice University has developed artificial intelligence (AI) models that help them better understand the brain computations that underlie thoughts. This is new, because until now there has been no method to measure thoughts. The researchers first developed a new model that can estimate thoughts by evaluating behavior, and then tested their model on a trained artificial brain where they found neural activity associated with those estimates of thoughts. The theoretical study appears in the Proceedings of the National Academy of Sciences.

“For centuries, neuroscientists have studied how the brain works by relating brain activity to inputs and outputs. For instance, when studying the neuroscience of movement, scientists measure muscle movements as well as neuronal activity, and then relate those two measurements,” said corresponding author Dr. Xaq Pitkow, assistant professor of neuroscience at Baylor and of electrical and computer engineering

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Scientists apply the METRIC model to estimate land surface evapotranspiration in Nepal

Scientists apply the METRIC model to estimate land surface evapotranspiration in Nepal
Simura station in Nepal. Credit: Weiqiang Ma

Evapotranspiration (ET), the phenomenon of the loss of water into the atmosphere from the land surface through evaporation and transpiration, is an important part of water and energy cycles. ET is a key variable used in applications such as drought monitoring, climate prediction, water resources management, and agricultural planning. The importance of a high-resolution ET estimation has also been well identified for agricultural applications where site-specific monitoring is needed, which is highly relevant for a country like Nepal that relies on agriculture for the majority share of its GDP and employment workforces.


Due to its importance, Prof. Weiqiang Ma from the Institute of Tibetan Plateau Research, Chinese Academy of Sciences, and his group, used the METRIC model to simulate and evaluate the surface evapotranspiration in Nepal. The results have been recently published in Atmospheric and Oceanic Science Letters.

According to the study

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Scientists find water microdroplets can transform into hydrogen peroxide when condensing on cold surfaces

Scientists find water microdroplets can transform into hydrogen peroxide when condensing on cold surfaces
Photo shows water microdroplet condensate formed on the surface of a glass container containing cold water (left) and an image of water microdroplets formed on a polished silicon surface (right). Credit: Jae Kyoo Lee and Hyun Soo Han

In its bulk liquid form, whether in a bathtub or an ocean, water is a relatively benign substance with little chemical activity. But down at the scale of tiny droplets, water can turn surprisingly reactive, Stanford researchers have discovered.


In microdroplets of water, just millionths of a meter wide, a portion of the H2O molecules present can convert into a close chemical cousin, hydrogen peroxide, H2O2, a harsh chemical commonly used as a disinfectant and hair bleaching agent.

Stanford scientists first reported this unexpected behavior in forcibly sprayed microdroplets of water last year. Now in a new study, the research team has shown the same Jekyll-and-Hyde

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