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Sat, 16 Oct 2021
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Dinosaur May Have Used Venom To Kill Prey

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© Wikimedia Commons
A fossil cast of what's believed to be a Sinornithosaurus is seen at the American Natural History museum in New York in this file photo.
If the thought of a voracious, razor-toothed dinosaur ripping into its prey isn't scary enough, consider a venomous dinosaur. That's what some scientists propose after discovering an unusual fossil in China.

Sinornithosaurus was petite as dinosaurs go - think of a turkey with teeth. It ran with a tough crowd, though; it was cousin to the oh-so-scary velociraptor of Jurassic Park fame.

Paleontologist David Burnham from the University of Kansas and a Chinese colleague were puzzled by a 125-million-year-old Sinornithosaurus fossil in a museum - specifically, by its upper teeth.

"We finally realized that we're looking at the outside of these teeth and they're grooved," Burnham recalls. "And we both looked at each other and thought,
'What? Why would an animal have grooved teeth?' "

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Scientists Shed Light on a Mysterious Particle, the Neutrino

Starting from the end of November, Queen Mary's Particle Physics Research Centre is the sole recipient of the T2K experiment data. The T2K Collaboration is a 500-strong alliance of scientists in 12 countries, who have come together to investigate the ghostly neutrino.

Physicist Dr Francesca Di Lodovico said: "Trillions of neutrinos pass through our bodies every second, but you don't notice; they pass through space and the Earth with almost no effect. This makes neutrinos very difficult to study and yet they are thought to play a fundamental role in the formation of the Universe and understanding where we came from."

Neutrinos come from outer space, either shot out from the Sun, or left over from the Big Bang. But despite their abundance, techniques to understand their nature have only been developed in the last few decades, giving surprising results.

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Microcephaly Genes Associated With Human Brain Size

A group of Norwegian and American researchers have shown that common variations in genes associated with microcephaly -- a neuro-developmental disorder in which brain size is dramatically reduced -- may explain differences in brain size in healthy individuals as well as in patients with neurological and psychiatric disorders.

The study, which involved collaboration between researchers from the University of Oslo, the University of California, San Diego and Scripps Translational Science Institute in La Jolla, California, will be published online the week of December 21 in the Proceedings of the National Academy of Science.

In relation to body size, brain size has expanded dramatically throughout primate and human evolution. In fact, in proportion to body size, the brain of modern humans is three times larger than that of non-human primates. The cerebral cortex in particular has undergone a dramatic increase in surface area during the course of primate evolution.

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Jesus-era home found in Nazareth

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Archaeologists in Israel say they have uncovered the remains of the first dwelling in Nazareth believed to date back to the time of Jesus Christ.

The discovery sheds light on how people lived 2,000 years ago, when Christians believe Jesus was growing up there, Israel's Antiquities Authority said.

A spokeswoman said Jesus and his childhood friends likely knew the home.

It was found near the place where angel Gabriel is believed to have told Mary that she would give birth to Jesus.

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Science's breakthrough of the year: Uncovering 'Ardi'

Fossil of early hominid heads the journal's list of top 10 scientific advances of 2009.

The research that brought to light the fossils of Ardipithecus ramidus, a hominid species that lived 4.4 million years ago in what is now Ethiopia, has topped Science's list of this year's most significant scientific breakthroughs. The monumental find predates "Lucy," - previously the most ancient partial skeleton of a hominid on record - by more than one million years, and it inches researchers ever-closer to the last common ancestor shared by humans and chimpanzees.

Sun

Supernova Explosions Stay In Shape

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© NASA/CXC/UCSC/L. Lopez et al.
At a very early age, children learn how to classify objects according to their shape. Now, new research suggests studying the shape of the aftermath of supernovas may allow astronomers to do the same.

A new study of images from NASA's Chandra X-ray Observatory on supernova remnants - the debris from exploded stars - shows that the symmetry of the remnants, or lack thereof, reveals how the star exploded. This is an important discovery because it shows that the remnants retain information about how the star exploded even though hundreds or thousands of years have passed.

"It's almost like the supernova remnants have a 'memory' of the original explosion," said Laura Lopez of the University of California at Santa Cruz, who led the study. "This is the first time anyone has systematically compared the shape of these remnants in X-rays in this way."

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Your Christmas Tree Has Seven Times More DNA Than You Do!

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© iStockphoto/Eva Serrabassa
Girl decorating a Christmas tree, which has seven times more DNA than she does.
Take a close look at your Christmas tree -- it has seven times more genetic material (DNA) than you do! Why this is so is still largely unknown, but now the DNA of the spruce is going to be mapped by Swedish researchers from Umeå Plant Science Center (a collaboration between the Swedish University of Agricultural Sciences (SLU) and Umeå University), the Royal Institute of Technology (KTH), and the Karolinska Institute (KI), with the aid of a SEK 75 million grant from the Knut and Alice Wallenberg Foundation.

Coniferous trees have dominated major parts of the earth for hundreds of millions of years. When primitive batrachians crawled around Carbon Age forests, they were surrounded by conifers. Conifers survived the geological disaster 250 million years ago that paved the way for the age of the dinosaurs. When the impact of a meteorite wiped out the dinosaurs, conifers lived on. Today conifers dominate major regions of the earth -- the combined weight of all the people on earth is less than that of the conifers in Jämtland County in central Sweden.

Apparently conifers managed as early as 300 million years ago to create an extremely successful genetic make-up that has allowed them to dominate the globe, but what does it look like? All conifers have twelve chromosomes, but they are extremely large: a cell from a spruce or pine has seven times as much DNA as a human cell does. Why do conifers have so much DNA? Does it have to do with their having thrived for millions of years on earth, and do they really have more genes than you and I, or are their genes simply more 'diluted'? This is not known, but their enormous amount of DNA has entailed that scientists have not dared to tackle a mapping of the complete genome of coniferous trees.

Sherlock

Sixty Headless Skeletons - 3,000 Years Old - Discovered in Pacific Ocean Archipelago Vanuatu

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© Mads Ravn/Courtesy of The University of Stavanger
The archaeologists found that Vanuatu skeletons are headless.
When a team of archaeologists began excavating an old coral reef in Vanuatu in 2008 and 2009, they soon discovered it had served as a cemetery in ancient times. So far, 71 buried individuals have been recorded, giving new information on the islands' inhabitants and their funeral rites.

"This is a groundbreaking discovery, as it is the oldest and biggest skeleton find ever in the Pacific Ocean; bigger cemeteries found further east are much younger," says Mads Ravn, head of research at the University of Stavanger's Museum of Archaeology in Norway.

Relatives did not treat their dead gently. Besides being headless, some of them had had their arms and legs broken, in order to fit into the coral reef cavities. Ravn suggests they may have been left to rot first, and buried later as skeletons.

The local museum's staff of the Vanuatu Culture Centre, a range of researchers, lead by Stuart Bedford and Matthew Spriggs from the Australian National University (ANU), forms an international and cross-disciplinary team, working to gather information about the Pacific islands' inhabitants. Mads Ravn's expertise in migration and colonising over great distances, as well as in digital excavation documentation and recording, makes him an important contributor to this cooperative effort.

Sherlock

Scientists Take a Step Towards Uncovering the Histone Code

Researchers at Emory University School of Medicine have determined the structures of two enzymes that customize histones, the spool-like proteins around which DNA coils inside the cell.

The structures provide insight into how DNA's packaging is just as important and intricate as the information in the DNA itself, and how these enzymes are part of a system of inspectors making sure the packaging is in order.

The results are published online this week in the journal Nature Structural and Molecular Biology.

A team of scientists led by Xiaodong Cheng, PhD, professor of biochemistry at Emory and a Georgia Research Alliance eminent scholar, used X-rays to probe the architecture of two enzymes, PHF8 and KIAA1718. The enzymes are known as histone demethylases because they remove methyl groups (chemical modifications of a protein) from histones.

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How Cancer Cells Protect Themselves from Low Levels of Oxygen

Not all regions of a tumor are equal in terms of their oxygen levels. One clinically important implication of this is that tumors with large areas with low levels of oxygen (areas known as hypoxic regions) are associated with poor prognosis and treatment response.

A team of researchers, led by Bradly Wouters, at the University of Toronto, Canada, has determined that a cellular response pathway known as the unfolded protein response pathway helps protect human tumor cells from hypoxia and anticancer irradiation treatment.

Further analysis indicated that the unfolded response pathway increased expression of two proteins involved in a cellular process known as autophagy, which is known to act to protect cells in times of stress.

Importantly, inhibition of autophagy sensitized cultured human tumor cells to hypoxia and sensitized human tumors xenografted into mice to irradiation, leading the authors to suggest that targeting the molecules they identified as important might be of clinical benefit.