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Categories: Anthropology: General, Chemistry: Organic Chemistry
Published Research reveals longstanding cultural continuity at oldest occupied site in West Africa
(via sciencedaily.com) Original source Stone tools recovered from near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published Single-molecule valve: Breakthrough in nanoscale control
(via sciencedaily.com) Original source A research group has succeeded in regulating the flow of single molecules in solution by opening and closing the nanovalve mounted on the nanofluidic device by applying external pressure. The research group fabricated a device with a ribbon-like, thin, soft glass sheet on the top, and at the bottom a hard glass substrate having nanochannels and nanovalve seats. By applying external pressure to the soft glass sheet to open and close the valve, they succeeded in directly manipulating and controlling the flow of individual molecules in solution. They also observed an effect of fluorescence signal amplification when single fluorescent molecules are confined in the tiny nanospace inside the valve. The effect can be ascribed to the nanoconfinement, which suppresses the random motion of the molecules.
Published Upcycling method turns textile trash to functional coatings
(via sciencedaily.com) Original source In an effort to make textiles more sustainable, a new method allows researchers to break old clothing down chemically and reuse polyester compounds to create fire resistant, anti-bacterial or wrinkle-free coatings that could then be applied to clothes and fabrics.
Published Self-folding origami machines powered by chemical reaction
(via sciencedaily.com) Original source Scientists have harnessed chemical reactions to make microscale origami machines self-fold -- freeing them from the liquids in which they usually function, so they can operate in dry environments and at room temperature.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.
Published Previously unknown intercellular electricity may power biology
(via sciencedaily.com) Original source Researchers have discovered that the electrical fields and activity that exist through a cell's membrane also exist within and around another type of cellular structure called biological condensates. Like oil droplets floating in water, these structures exist because of differences in density. Their foundational discovery could change the way researchers think about biological chemistry. It could also provide a clue as to how the first life on Earth harnessed the energy needed to arise.
Published New research redefines mammalian tree of life
(via sciencedaily.com) Original source Scientists from around the globe are using the largest mammalian genomic dataset in history to determine the evolutionary history of the human genome in the context of mammalian evolutionary history. Their ultimate goal is to better identify the genetic basis for traits and diseases in people and other species.
Published Pulling the plug on viral infections: CRISPR isn't just about cutting
(via sciencedaily.com) Original source CRISPR claimed scientific fame for its ability to quickly and accurately edit genes. But, at the core, CRISPR systems are immune systems that help bacteria protect themselves from viruses. A new study reveals a previously unrecognized player in one such system -- a membrane protein that enhances anti-viral defense. According to study authors, the finding upends the idea that CRISPR systems mount their defense only by degrading RNA and DNA in cells.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.
Published Elephant ecosystems in decline
(via sciencedaily.com) Original source Global space for Asian elephant habitats has been in rapid decline since the 1700s, a new report reveals. More than 3 million square kilometers of the Asian elephant's historic habitat range has been lost in just three centuries and may underlie present-day conflicts between elephants and people.
Published A transistor made of wood
(via sciencedaily.com) Original source Researchers have developed the first transistor made of wood. Their study paves the way for further development of wood-based electronics and control of electronic plants.
Published How spheres become worms
(via sciencedaily.com) Original source A previously unknown form of hydrogel formation has been elucidated: chemists found unusual interactions between polymers.
Published Prolonged droughts likely spelled the end for Indus megacities
(via sciencedaily.com) Original source New research has found evidence -- locked into an ancient stalagmite from a cave in the Himalayas -- of a series of severe and lengthy droughts which may have upturned the Bronze Age Indus Civilization.
Published Brain circuits for locomotion evolved long before appendages and skeletons
(via sciencedaily.com) Original source Scientists found parallels between the neural circuitry that guides locomotion in sea slugs and in more complex animals like mammals.
Published A simple paper test could offer early cancer diagnosis
(via sciencedaily.com) Original source Engineers designed a nanoparticle sensor that could enable early diagnosis of cancer with a simple urine test. The sensors, which can detect many cancerous proteins, could also be used to distinguish the type of a tumor or how it is responding to treatment.
Published CO2 recycling: What is the role of the electrolyte?
(via sciencedaily.com) Original source The greenhouse gas carbon dioxide can be converted into useful hydrocarbons by electrolysis. The design of the electrolysis cell is crucial in this process. The so-called zero-gap cell is particularly suitable for industrial processes. But there are still problems: The cathodes clog up quickly.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published Outstanding performance of organic solar cell using tin oxide
(via sciencedaily.com) Original source Organic solar cells have a photoactive layer that is made from polymers and small molecules. The cells are very thin, can be flexible, and are easy to make. However, the efficiency of these cells is still much below that of conventional silicon-based ones. Applied physicists have now fabricated an organic solar cell with an efficiency of over 17 percent, which is in the top range for this type of material. It has the advantage of using an unusual device structure that is produced using a scalable technique.
Published Researchers team up with national lab for innovative look at copper reactions
(via sciencedaily.com) Original source Researchers are working to get a better look at how peroxides on the surface of copper oxide promote the oxidation of hydrogen but inhibit the oxidation of carbon monoxide, allowing them to steer oxidation reactions.