Tooth unlocks mystery of Denisovans in Asia

Views of the TNH2-1 specimen
Credit: Flinders University

What links a finger bone and some fossil teeth found in a cave in the remote Altai Mountains of Siberia to a single tooth found in a cave in the limestone landscapes of tropical Laos?

The answer to this question has been established by an international team of researchers from Laos, Europe, the US and Australia.

The human tooth was chanced upon during an archaeological survey in a remote area of Laos. The scientists have shown it originated from the same ancient human population first recognized in Denisova Cave (dubbed the Denisovans), in the Altai Mountains of Siberia (Russia).

The research team made the significant discovery during their 2018 excavation campaign in northern Laos. The new cave Tam Ngu Hao 2, also known as Cobra Cave, is located near to the famous Tam Pà Ling Cave where another important 70,000-year-old human (Homo sapiens) fossils had been previously found.

The international researchers are confident the two ancient sites are linked to Denisovans occupations despite being thousands of kilometers apart.

How ice clouds develop – Asian monsoon influences large parts of the Northern Hemisphere

Air pollutants form the condensation nuclei for ice clouds or cirrus clouds (here: Cirrus spissatus). When ammonia, nitric acid and sulfuric acid are present together, they form such condensation nuclei particularly effectively.
Credit: Joachim Curtius, Goethe-University Frankfurt

Atmospheric researchers from the international CLOUD consortium have discovered a mechanism that allows nuclei for ice clouds to form and rapidly grow in the upper troposphere. The discovery is based on cloud chamber experiments to which a team from Goethe University contributed highly specialized measurements. Although the conditions for nucleus formation are only fulfilled in the Asian monsoon region, the mechanism is expected to have an impact on ice cloud formation across large parts of the Northern Hemisphere. 

The Asian monsoon transports enormous amounts of air from atmospheric layers close to Earth's surface to a height of around 15 kilometers. Like in a gigantic elevator, human-induced pollutants also end up in the upper troposphere in this way. A research team from the CLOUD consortium (Cosmics Leaving Outdoor Droplets), including atmospheric researchers from Goethe University in Frankfurt, have reproduced the conditions prevailing there, among them cosmic radiation, in their experimental chamber at the CERN particle accelerator center in Geneva.

Biological crusts influence the climate

Biological soil crusts strengthen the soil and ensure that less sand is stirred up and thus fewer dust particles are released into the atmosphere.
Credit: Emilio Rodriguez-Caballero

A surface layer of bacteria, fungi and lichen amongst others reduces the amount of dust stirred up into the atmosphere

When bacteria, fungi, mosses, lichens and algae combine on dry land, they form so-called biological soil crusts. These cover about twelve percent of the total global land surface, and up to one third of the surface in dry areas. Biological soil crusts play an important role in consolidating soils, making them more stable and less likely to be stirred up by the wind. Since dust particles in the atmosphere have an impact on the climate, soil crusts fulfil an important function in several respects. An international team of researchers around biologist Bettina Weber of the University of Graz and research associate of the Max Planck Institute for Chemistry provide, for the first time, comprehensive facts and figures on the importance of biological soil crusts for the regional and global dust cycle, both under current and future conditions.

The dwarf planet Ceres was formed in the coldest zone of Solar System and thrust into Asteroid Belt

The dwarf planet Ceres in an image captured by NASA’s Dawn Mission. The bright white spot is a reflection of sunlight from ice deposits at the bottom of the crater
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

In an article published in the journal Icarus, researchers at São Paulo State University (UNESP) and collaborators report the findings of a study reconstituting the formation of the dwarf planet Ceres.

The research was conducted by Rafael Ribeiro de Sousa, a professor in the program of graduate studies in physics on the Guaratinguetá campus. The co-authors of the article are Ernesto Vieira Neto, who was Ribeiro de Sousa’s PhD thesis advisor, and researchers affiliated with Côte d’Azur University in France, Rice University in the United States, and the National Observatory in Rio de Janeiro.

Ceres is the largest object in the Asteroid Belt, a collection of celestial bodies located between the orbits of Mars and Jupiter. It is roughly spherical and comprises a third of the Asteroid Belt’s total mass, with a diameter of almost 1,000 km, less than a third of the Moon’s.

Its orbit around the Sun is almost perfectly circular, with 0.09 eccentricity, and an inclination of 9.73° to the invariable plane of the Solar System, much greater than Earth’s, which is 1.57°.

Researchers developed invisible, machine-washable solar cell technology for clothing

The Sun-powered Textiles project looked for ways to seamlessly combine solar cells and textiles. Photo: Anne Kinnunen/Aalto University

The discrete nature of the cells protects them – and makes the clothes more attractive, the physics and design researchers say. Promising applications include work and outdoor clothing, and curtains which react to changes in the amount of light.

Lasting power and efficient recycling

Any solar cell placed under the textile it adheres to has to have a significantly larger surface area than a cell that’s placed on top. A piece of regular fabric eats up roughly 70 percent of a cell’s capacity - with a more porous fabric the percentage is smaller.

Key factors in the ability of textiles to let light through them include the material, transparency and crosscut of the fiber, structure of the threads, thickness and weave of the fabric, colors and the finish. Light colors transmit light better than dark colors, but a pitch-black and completely opaque fabric can also work.

The commercial solar cells used in the study comprised of a single crystal and were made of silicon. They can detect light that is invisible to the naked eye, which is what most sunlight actually is. Infrared is an example of such invisible light.

Mystery of seafloor metamorphosis unlocked

An adult tubeworm, in its tube, with its plume of tentacles extended.
Photo credit: Freckelton et al. 2022

Most bottom-dwelling marine invertebrate animals, such as sponges, corals, worms and oysters, produce tiny larvae that swim in the ocean prior to attaching to the seafloor and transforming into juveniles. A study published in the Proceedings of the National Academy of Sciences and led by University of Hawaiʻi at Mānoa researchers revealed that a large, complex molecule, called lipopolysaccharide, produced by bacteria is responsible for inducing larval marine tubeworms, Hydroides elegans, to settle to the seafloor and begin the complex processes of metamorphosis.

“This is a major milestone in understanding the factors that determine where larvae of bottom-living invertebrates settle and metamorphose,” said Michael Hadfield, senior author on the paper and emeritus professor in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST). “It is the key to understanding how benthic (underwater) communities are established and maintained on all surfaces under salt water, that is, on 71% of Earth’s surface.”

Scientists 'see' puzzling features deep in Earth’s interior

Etna Volcano Eruption January 12th 2011
Credit: gnuckx

New research led by the University of Cambridge is the first to obtain a detailed 'image' of an unusual pocket of rock at the boundary layer with Earth’s core, some three thousand kilometers beneath the surface.

The enigmatic area of rock, which is located almost directly beneath the Hawaiian Islands, is one of several ultra-low velocity zones – so-called because earthquake waves slow to a crawl as they pass through them.

The research, published in Nature Communications, is the first to reveal the complex internal variability of one of these pockets in detail, shedding light on the landscape of Earth’s deep interior and the processes operating within it.

“Of all Earth’s deep interior features, these are the most fascinating and complex. We’ve now got the first solid evidence to show their internal structure - it’s a real milestone in deep earth seismology,” said lead author Zhi Li, PhD student at Cambridge’s Department of Earth Sciences.

“Natural Immunity” from Omicron is Weak and Limited

The new study shows that infection with Omicron does not protect against other variants of COVID-19. In this photo, clear zones on the purple background show the SARS-CoV-2 virus escaping from neutralizing antibodies in patient blood samples.
Credit: Gladstone Institutes

In unvaccinated people, infection with the Omicron variant of SARS-CoV-2 provides little long-term immunity against other variants, according to a new study by researchers at Gladstone Institutes and UC San Francisco (UCSF), published today in the journal Nature.

In experiments using mice and blood samples from donors who were infected with Omicron, the team found that the Omicron variant induces only a weak immune response. In vaccinated individuals, this response—while weak—helped strengthen overall protection against a variety of COVID-19 strains. In those without prior vaccination, however, the immune response failed to confer broad, robust protection against other strains.

“In the unvaccinated population, an infection with Omicron might be roughly equivalent to getting one shot of a vaccine,” says Melanie Ott, MD, PhD, director of the Gladstone Institute of Virology and co-senior author of the new work. “It confers a little bit of protection against COVID-19, but it’s not very broad.”

Banned Contaminants Still Threaten Endangered California Condors

Condors at Pinnacles National Park in central California.

Photo courtesy of San Diego Zoo Wildlife Alliance

A new study has found contaminants that were banned decades ago are still imperiling critically endangered California condors. The condors may be at increased risk for reproductive impairment because they consume dead marine mammals along the California coast.

The research, led by San Diego State University (SDSU) and San Diego Zoo Wildlife Alliance (SDZWA) scientists, in collaboration with Centro de Investigación Científica y de Educación Superior de Ensenada and the National Oceanographic and Atmospheric Administration, found that marine mammals stranded on the California coast harbor relatively high levels of halogenated organic contaminants (HOCs). Researchers detected more than 400 contaminants in samples taken from stranded marine mammals that California condors may feed on.

On the California coast, the marine mammals had an estimated seven times more DDT and 3.5 times more PCBs than their counterparts in Baja California, Mexico. Other lesser-studied compounds were also detected. One group of these compounds was estimated to be 148 times more abundant in California marine mammals compared to those in Baja California.

The study, published in the journal Environmental Science & Technology, also reveals that coastal condors have more contaminants in their blood than inland condors, which lack a marine mammal diet.

Choline makes key nutrients available for baby development

Choline Molecule 
Choline occurs in foods as a free molecule and in the form of phospholipids, especially as phosphatidylcholines. Choline is highest in organ meats and egg yolks though it is found to a lesser degree in non-organ meats, grains, vegetables, fruit and dairy products.

The nutrient choline – shown to have long-term benefits for children whose mothers consume it during pregnancy – also helps the body more efficiently use an omega 3 fatty acid that is essential for fetal brain, cognition and vision development, a new study finds.

The study was published in the American Journal of Clinical Nutrition.

The findings show that choline supplementation supports cellular metabolism to more efficiently handle and release the omega 3 fatty acid, DHA, from a pregnant individual’s liver. Once released into the bloodstream, DHA can be delivered into all the tissues, including the placenta.

“During pregnancy, mom is primed to get nutrients out of the liver and make them available to the baby, so by supplementing choline and DHA [together], we are increasing DHA bioavailability,” said senior author Marie Caudill, professor of nutritional sciences in the College of Agriculture and Life Sciences. Kevin Klatt, Ph.D. ’18, a research scientist and registered dietitian at the University of California, Berkeley, is the paper’s first author.