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Giant Neuron Found That Wraps Around the Entire Circumference of the Brain

Giant Neuron Found That Wraps Around the Entire Circumference of the Brain | Amazing Science | Scoop.it

For the first time, scientists have detected a giant neuron wrapped around the entire circumference of a mouse's brain, and it's so densely connected across both hemispheres, it could finally explain the origins of consciousness. 

 

Using a new imaging technique, the team detected the giant neuron emanating from one of the best-connected regions in the brain, and say it could be coordinating signals from different areas to create conscious thought.

 

This recently discovered neuron is one of three that have been detected for the first time in a mammal's brain, and the new imaging technique could help us figure out if similar structures have gone undetected in our own brains for centuries.

 

At a recent meeting of the Brain Research through Advancing Innovative Neurotechnologies initiative in Maryland, a team from the Allen Institute for Brain Science described how all three neurons stretch across both hemispheres of the brain, but the largest one wraps around the organ's circumference like a "crown of thorns". 

 

You can see them highlighted in the image at the top of the page.

Lead researcher Christof Koch told Sara Reardon at Nature that they've never seen neurons extend so far across both regions of the brain before.

 

Oddly enough, all three giant neurons happen to emanate from a part of the brain that's shown intriguing connections to human consciousness in the past - the claustrum, a thin sheet of grey matter that could be the most connected structure in the entire brain, based on volume.


Via Wildcat2030, Miloš Bajčetić, Tania Gammage, CineversityTV
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compressedpiano's comment, February 28, 10:51 PM
This is so great!
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Bumblebees leave smelly footprints as they search for food

Bumblebees leave smelly footprints as they search for food | Amazing Science | Scoop.it

Smelly footprints left by bumblebees can help them find good sources of food. The insects secrete invisible markers when they touch their feet on a surface, which can be detected by themselves and other bumblebees. Researchers from the University of Bristol, in the UK, found that bees can distinguish between their own scent, the scent of a relative and that of a stranger. This ability can be used to improve their success at finding good sources of food and avoiding flowers that have already been visited and mined of nutrients.

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The Purpose of Sleep is to Forget

The Purpose of Sleep is to Forget | Amazing Science | Scoop.it

Over the years, scientists have come up with a lot of ideas about why we sleep. Some have argued that it’s a way to save energy. Others have suggested that slumber provides an opportunity to clear away the brain’s cellular waste. Still others have proposed that sleep simply forces animals to lie still, letting them hide from predators.

 

A pair of papers published on Thursday in the journal Science offer evidence for another notion: We sleep to forget some of the things we learn each day.

 

In order to learn, we have to grow connections, or synapses, between the neurons in our brains. These connections enable neurons to send signals to one another quickly and efficiently. We store new memories in these networks.

 

In 2003, Giulio Tononi and Chiara Cirelli, biologists at the University of Wisconsin-Madison, proposed that synapses grew so exuberantly during the day that our brain circuits got “noisy.” When we sleep, the scientists argued, our brains pare back the connections to lift the signal over the noise.

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Kea parrot shows cooperation and smarts like chimps, elephants and children

Kea parrot shows cooperation and smarts like chimps, elephants and children | Amazing Science | Scoop.it

Cooperation between individuals is one of the defining features of our species. While other animals, such as chimpanzees, elephants, coral trout and rooks also exhibit cooperative behaviors, it is not clear if they think about cooperation in the same way as humans do. In this study scientists presented the kea, a parrot endemic to New Zealand, with a series of tasks designed to assess cooperative cognition. They found that keas were capable of working together, even when they had to wait for their partner for up to 65 seconds. The keas also waited for a partner only when a partner was actually needed to gain food.

 

This is the first demonstration that any non-human animal can wait for over a minute for a cooperative partner, and the first conclusive evidence that any bird species can successful track when a cooperative partner is required, and when not. The keas did not attend to whether their partner could actually access the apparatus themselves, which may have been due to issues with task demands, but one kea did show a clear preference for working together with other individuals, rather than alone. This preference has been shown to be present in humans but absent in chimpanzees.

 

Taken together, these results provide the first evidence that a bird species can perform at a similar level to chimpanzees and elephants across a range of collaborative tasks. This raises the possibility that aspects of the cooperative cognition seen in the primate lineage have evolved convergently in birds.

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Even tiny bumblebee brains can solve complex problems and teach others

Even tiny bumblebee brains can solve complex problems and teach others | Amazing Science | Scoop.it

Lars Chittka didn’t expect much when he decided to see if bumblebees could learn to pull a string for a reward. While animals from birds to apes can solve this puzzle, it seemed unlikely that bees could solve it too because they have such tiny brains. “I asked what may have seemed an entirely mad question,” says Chittka, a behavioral ecologist at Queen Mary University of London.

 

But it turned out not be mad in the slightest. In new research reported in PLOS Biology, Chittka and his colleagues got a “big surprise”: they found that bumblebees could easily be trained to pull strings for sugar water.

 

First the researchers attached strings to blue discs with sugar water in the middle, and then let the bees learn that these fake flowers held a reward. The next step was putting the flowers under plexiglass – only the very tips of the strings were within reach. This was the first test of string pulling in an insect.

 

With this training, more than half of the bees solved the puzzle, vigorously pulling the string toward them until they could drink the sweet reward in the flower. Another experiment showed that while untrained bees rarely learned this skill on their own, a few actually did. “This was even more of a surprise,” Chittka says.

 

The researchers also found that this new skill spread socially and culturally from bee to bee. After watching trained bees demonstrate their string-pulling prowess, 60 percent of untrained bees solved the problem on their own. And adding a single trained bee to a colony of untrained bees was enough for many of them to acquire the skill.

 

“This was the final surprise – there is still a common perception that humans, and especially the cultural processes seen in humans, are unique in their cognitive performances,” Chittka says. “It’s tempting to assume that a large brain is a prerequisite for such phenomena.” But, as his work shows, problem solving and cultural transmission don’t necessarily take much brainpower.

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The Extinction of Primates: 60 percent of the 500 known primate species are on the verge of extinction

The Extinction of Primates: 60 percent of the 500 known primate species are on the verge of extinction | Amazing Science | Scoop.it

A new research study has found that around 60 percent of the 500 known primate species are on the verge of extinction. With around 75 percent of all species declining in numbers, this new discovery sparked an uproar in the scientific community who are now calling to raise global awareness of the plight of the world’s primates and the costs of their loss to ecosystem health and human society.

 

Primates are essential to biodiversity in the tropics, contribute to natural regeneration and are important to many cultures and religions. In order to study the effect human activity has on primate survival, researchers combined data from the International Red List of the world nature conservation organization International Union for the Conservation of Nature (IUCN) with data from the United Nations (UN) database to establish forecasts and development trends for the next 50 years.

 

Based on this data, researchers were able to establish forecasts and development trends for the next 50 years. They determined that a primate’s natural habitat is situated in areas that experience high levels of poverty and lack of education. As a result, locals tend to hunt primates for meat and supply the illegal pet trade. The scientists predict that within the next fifty years, we will experience extinction events for many different primate species, like the ring-tailed lemur, eastern gorilla, and baboons.

 

“Conservation is an ecological, cultural and social necessity. When our closest relatives, the non-human primates, become extinct, this will send a warning signal that the living conditions for humans will soon deteriorate dramatically,” says Eckhard W. Heyman a scientist at the German Primate Center  (DPZ) and a co-author of the study.

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Consensus statement: Virus taxonomy in the age of metagenomics

Consensus statement: Virus taxonomy in the age of metagenomics | Amazing Science | Scoop.it

Viruses are obligate intracellular parasites that probably infect all cellular lifeforms. Although virologists have traditionally focused on viruses that cause disease in humans, domestic animals and crops, the recent advances in metagenomic sequencing, in particular high-throughput sequencing of environmental samples, have revealed a staggeringly large virome everywhere in the biosphere. At least 10^31 virus particles exist globally at any given time in most environments, including marine and freshwater habitats and metazoan gastrointestinal tracts, in which the number of detectable virus particles exceeds the number of cells by 10–100-fold1, 2, 3, 4, 5.

 

To help conceptualize the sheer number of viruses in existence, their current biomass has been estimated to equal that of 75 million blue whales (approximately 200 million tons) and, if placed end to end, the collective length of their virions would span 65 galaxies6. In addition to their remarkable abundance, viruses are spectacularly diverse in the nature and organization of their genetic material, gene sequences and encoded proteins, replication mechanisms, and interactions with their cellular hosts, whether they are antagonistic, commensal or mutualistic7.

 

Aquatic environments contain particularly diverse forms of viruses, including single-stranded (ss) and double-stranded (ds) DNA and RNA viruses with genomes that range in size from less than 2,000 bases to more than 2 million bases4. Although dsDNA viruses that infect bacteria (bacteriophages) are the best studied viruses to date, recent work suggests that around 50% of marine viruses have ssDNA or RNA genomes8.

 

Metagenomic data are changing our views on virus diversity and are therefore challenging the way in which we recognize and classify viruses9. Historically, the description and classification of a new virus by the International Committee on Taxonomy of Viruses (ICTV) have required substantial information on host range, replication cycle, and the structure and properties of virus particles, which were then used to define groups of viruses. However, high-throughput sequencing and metagenomic approaches have radically changed virology, with many more viruses now known solely from sequence data than have been characterized experimentally. For example, the family Genomoviridae currently comprises a single classified virus, whereas more than 120 possible members have been sequenced from diverse environments. However, these sequenced viruses lack information about their hosts and other biological properties that would guide their assignment into species and genera in the family10.

 

Indeed, vast numbers of complete, or nearly complete, genome sequences have been assembled and characterized from metagenomic data for viruses with small11, 12, 13, 14, medium15, 16, 17, 18 and even large19, 20genomes. The identification of entirely new groups of viruses from such analyses emphasizes the power of metagenomic approaches in discovering viruses, some of which could have key functions in the regulation of ecosystems, whereas others could coexist with their hosts without causing recognizable disease or may even be mutualists7. However, realistically, few of these viruses are ever likely to receive the same level of experimental characterization as pathogens that cause human disease or influence the global economy.

 

The question of whether viruses that are identified by metagenomics can, and should, be incorporated into the official ICTV taxonomy scheme on the basis of sequence data alone is pressing. In response to this question, a workshop of invited experts in the field of virus discovery and environmental surveillance, and members of the ICTV Executive Committee, took place in June 2016 to discuss this possibility and to develop a framework for appropriate approaches to virus classification.

 


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Ebolaviruses need very few mutations to cause disease in new host species

Ebolaviruses need very few mutations to cause disease in new host species | Amazing Science | Scoop.it

Kent researchers have identified how few mutations it can take for Ebolaviruses to adapt to affect previously resistant species.

Ebola is one of the world's most virulent diseases, though rodent species such as guinea pigs, rats and mice are not normally susceptible to it. However, through repeated infection of a host animal, Ebola virus strains can be generated that replicate and cause disease within new host rodent species.

 

Scientists in the University of Kent's School of Biosciences examined the changes associated with Ebolavirus adaptation to rodents including guinea pigs and mice across four different studies. They found that only very few mutations, probably fewer than five, are required for the virus to adapt. In particular, a change in the Ebolavirus protein VP24 seems to be critical for Ebola viruses to infect a new animal species. Ebolaviruses infecting domestic species, including pigs and dogs, may also result in virus changes that may increase the risk to humans. Reston viruses, Ebolaviruses that have not been shown to cause disease in humans, so far, are known to circulate in domestic pigs in Asia.

 

The research was performed by Dr Mark Wass (Senior Lecturer in Computational Biology), Professor Martin Michaelis (Professor of Molecular Medicine), and Dr Jeremy Rossman (Senior Lecturer in Virology) and members of their research groups. The research, entitled Changes associated with Ebola virus adaptation to novel species, was published in the journal Bioinformatics (https://academic.oup.com/bioinformatics/article-lookup/doi/10.1093/bioinformatics/btx065).

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Scientists discover how epithelial cells maintain constant cell numbers

Scientists discover how epithelial cells maintain constant cell numbers | Amazing Science | Scoop.it

Research published today in Nature from scientists at Huntsman Cancer Institute (HCI) at the University of Utah shows how epithelial cells naturally turn over, maintaining constant numbers between cell division and cell death.

Epithelial cells comprise the skin and skin-like linings that coat internal organs, giving organs a protective barrier so they can function properly. Cells turn over very quickly in epithelia. To maintain healthy cell densities, an equal number of cells must divide and die. If that balance gets thrown off, inflammatory diseases or cancers can arise.

 

The study leader, Jody Rosenblatt, PhD, investigator at HCI and associate professor of oncological sciences at the University of Utah, says, "If too many epithelial cells die, you can lose the organ barrier function and inflammatory diseases like asthma and colitis can result. On the other hand, if too many cells divide compared to the number dying, this can cause an overabundance of cells, which can lead to tumor formation. So imbalance on either side is problematic."

 

Around ninety percent of cancers arise in the simple epithelia that coat the organs. Understanding what normally controls cell division and death, and how these processes are linked, is essential to understanding how these events become misregulated to drive cancer formation. While scientists had previously studied cell division and death in response to experimental triggers, how these processes naturally occur was less clear.

 

The HCI team discovered an answer to this puzzle. They learned that opposing mechanical tensions control both cell division and cell death. Specifically, they found that stretching epithelial cells causes them to divide, and crowding epithelial cells causes them to expel and die. "We knew there had to be some kind of regulation to tie the death and division processes together," says Rosenblatt. "What we found boils down to really simple principles. It's all mechanical tension. If the cells get too crowded—1.6-fold more crowded - then they pop some cells out that later die. The extrusion of cells enables the cell sheets to return to densities they like."


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Molecular patterns of complex diseases

Molecular patterns of complex diseases | Amazing Science | Scoop.it

The Helmholtz Zentrum München has published results of the largest genome-wide association study on proteomics to date. An international team of scientists reports 539 associations between protein levels and genetic variants in ‘Nature Communications’. These associations overlap with risk genes for 42 complex diseases.

 

Genome-wide association studies (GWAS) provide an opportunity to associate concentration changes in certain proteins or metabolic products with gene loci. Knowledge of these genes makes it possible to establish connections to complex diseases. Scientists utilize the fact that to date, hundreds of associations between genetic variants and complex diseases have been demonstrated. These associations are immensely important because they do help uncover the underlying molecular mechanisms.

 

"In the world's largest proteomics GWAS to date, we worked with colleagues* to examine blood samples from 1,000 participants in the KORA study**," reports Dr. Gabi Kastenmüller. She is acting director and head of the Metabolomics Group at the Institute of Bioinformatics and Systems Biology (IBIS) at the Helmholtz Zentrum München. The team quantified a total of 1,100 proteins. Dr. Christian Gieger, head of the Molecular Epidemiology Research Unit (AME) at the Helmholtz Zentrum München, adds: "We found 539 independent associations between protein levels and genetic variants." These overlap with genetic risk variants for 42 complex conditions, such as cardiovascular diseases and Alzheimer's disease.

 

"Our results provide new insights into the biological processes that are influenced by a very wide range of complex diseases and that can be used as a basis for the development of new strategies to predict and prevent these diseases," Gieger states. The team is now planning to investigate the exact mechanisms behind the new gene-protein associations.


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Cocktail of bacteria-killing viruses prevents cholera infection in animal models

Cocktail of bacteria-killing viruses prevents cholera infection in animal models | Amazing Science | Scoop.it

Oral administration of a cocktail of three viruses, all of which specifically kill cholera bacteria, prevents infection and cholera-like symptoms in animal model experiments, report scientists from Tufts University School of Medicine (TUSM) and the Sackler School of Graduate Biomedical Sciences at Tufts inNature Communications on Feb. 1. The findings are the first to demonstrate the potential efficacy of bacteria-killing viruses—known as bacteriophages, or phages—as an orally administered preventive therapy against an acute gastrointestinal bacterial disease.

 

“While phage therapy has existed for decades, our study is proof-of-principle that it can be used to protect against infection and intervene in the transmission of disease,” said senior study author Andrew Camilli, Ph.D., Howard Hughes Medical Institute Investigator and professor of molecular biology and microbiology at TUSM. “We are hopeful that phages can someday be a tool in the public health arsenal that helps decrease the global burden of cholera, which affects up to four million people around the world each year.”

 

In previous work, Camilli and colleagues searched for phages that are specific for Vibrio cholerae, the bacterium that causes cholera—a potentially lethal infectious disease marked by severe diarrhea and dehydration. While phages that kill V. cholerae are abundant in nature, the team identified three strains that uniquely retained the ability to kill V. cholerae within the small intestine, the site of infection in humans. These phages function by targeting bacterial surface receptors normally involved in infectiousness, making them ideal therapeutic candidates—to develop resistance, cholera bacteria must acquire mutations in these receptors, which cause the bacteria to become less infectious.

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Ed Rybicki's curator insight, February 13, 5:08 AM
While this great, it is a modern vindication of something no less a person that the co-discoverer of phages himself, Felix d'Herelle, advocated as a cure for dysentery - and put into practice in India in the 1920s, apparently (https://rybicki.wordpress.com/2015/02/17/happy-centenary-phages/). He was also the godfather of work done at the Eliava Institute in Georgia, which really laid the foundation of phage therapy.
Ed Rybicki's comment, February 13, 5:09 AM
Thanks! Great stuff.
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Silent Communication: RNA Interference Between Different Plant Species

Silent Communication: RNA Interference Between Different Plant Species | Amazing Science | Scoop.it
Plants and fungi can use conserved RNA interference machinery to regulate each other’s gene expression—and scientists think they can make use of this phenomenon to create a new generation of pesticides.

 

Plants, silent as they are to our ears, are in constant conversation with their environment. As scientists have developed ever-more-sensitive tools to eavesdrop on this molecular chatter, they’ve discovered not only dialogue among the cells of an individual plant and with the plant’s immediate surroundings, but between different individuals, sometimes of different species and even different kingdoms. The alphabet of this lingua franca is A, C, G, and U.

 

Noncoding RNAs are well known for their ability to control gene expression in cells. And as scientists have demonstrated repeatedly, protein production can be affected not just by RNAs made in the same individual, but by RNAs from altogether different organisms. In recent years, researchers have taken advantage of the ability to traffic RNA between distantly related taxa to selectively inhibit the expression of genes in fungi important for their growth, an approach they say might lead to the development of disease-resistant crops. Scientists have also shown in the lab that this cross-kingdom RNA transfer can go both ways: fungi are also sending RNA dispatches to their plant hosts, and the covert operation could be aiding their invasion.

In this conversation between plants and fungi, the organisms rely on a well-worn mechanism of gene-expression regulation that has stood the test of evolutionary time: RNA interference (RNAi).

 

Listening in on the RNA crosstalk between plants and their pathogens could reveal previously unknown facets of basic plant biology, and point the way toward a successful strategy to fend off crop pathogens. Yet, scientists’ manipulation of cross-kingdom RNAi using plants predates their full understanding of exactly how it works or how often it happens in nature.


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Plant keeps moths captive inside its fruits for almost a year

Plant keeps moths captive inside its fruits for almost a year | Amazing Science | Scoop.it

Some moths use fruit of trees they pollinate as food for their larvae, but one East Asian moth matures within the fruit right until adulthood.

 

Visit a forest in south-east China, say, in mid-March and you might catch one of the more unusual sights in the natural world. The ripe fruit of one species of tree burst open at that time each year – and fully developed moths fly out. Leafflower moths have a special relationship with leafflower trees, of the genus Glochidion. The trees produce male and female flowers in April and May. Most insects overlook them by day, perhaps because they don’t produce nectar.

 

At night, though, the flowers release a perfume that is irresistible to leafflower moths. Females flock to the trees and perform a very specific routine. First, they visit the male flowers, where they carefully collect pollen on their proboscis. Then they head to a female flower, using the pollen to fertilize the bloom. Pollination complete, they lay one egg in the flower. A few months later, the egg hatches. By that time, the fertilized flower should have matured into a fruit, providing the larva with food – it eats two or three of the half-dozen seeds inside.

 

Eventually the intimate relationship with the trees ends when the larva chews its way out of the fruit, pupates on the forest floor over winter and emerges as an adult moth in the spring.

 

One species – E. lanceolaria – does things a little differently. It still lays its eggs in April and May, but the species of tree it chooses – G. lanceolarium – takes ages to bear fruit. In fact, it isn’t until January of the following year that the fruit begin to develop. Only at this point do the larvae emerge from their eggs and begin to feed on the fruit.

 

With their development squeezed into a few short months, the larvae simply metamorphose into adults while still inside the fruit. A few weeks later, in March, the fruits mature – and the moths fly out, just in time to mate and lay their eggs in the tree’s new blooms.

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Study identifies key factor in DNA damage associated with aging 

Study identifies key factor in DNA damage associated with aging  | Amazing Science | Scoop.it

In a recent study, Rochester scientists made two important contributions to DNA damage research. First, though scientists could previously point to an association between DNA damage and aging, the Rochester group has demonstrated a causal relationship between reduced DNA damage and extended lifespan. Second, the researchers have identified a cellular factor—an enzyme called topoisomerase 2, or Top2, implicated in DNA damage—that can be targeted to reduce that damage. The findings are published in the journal Aging.

 

“This part of the puzzle has been missing from the DNA damage theory of aging,” says David Goldfarb, professor of biology. There are many examples of DNA damage being associated with aging, but never has a reduction in DNA damage been shown to extend lifespan. The study also shows how this information may have therapeutic potential.

 

Goldfarb’s lab exposed yeast—which ages much like humans—to a lifespan-shortening, drug-like molecule that acts on Top2 and helped the lab uncover Top2’s role. Top2 introduces double strand breaks into DNA as part of its catalytic cycle. The breaks must then be resealed. “Every once in a while Top2 gets trapped on the DNA before it can seal the breaks,” Goldfarb says. “When that happens, at least in young cells, there are a number of back-up systems that recognize the breaks and repair them.”

 

However, a number of researchers have shown that DNA damage repair systems decline as cells age, causing the unrepaired DNA breaks created by Top2 to persist. The unrepaired double strand breaks cause aging, diseases like cancer, and, ultimately, death.


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DNA sequencing gives clues to why woolly mammoth died out

DNA sequencing gives clues to why woolly mammoth died out | Amazing Science | Scoop.it

The last woolly mammoths to walk the Earth were so wracked with genetic disease that they lost their sense of smell, shunned company, and had a strange shiny coat. That's the verdict of scientists who have analyzed ancient DNA of the extinct animals for mutations. The studies suggest the last mammoths died out after their DNA became riddled with errors. The knowledge could inform conservation efforts for living animals.

 

There are fewer than 100 Asiatic cheetahs left in the wild, while the remaining mountain gorilla population is estimated at about 300. The numbers are similar to those of the last woolly mammoths living on Wrangel Island in the Arctic Ocean around 4,000 years ago.

 

Dr Rebekah Rogers of the University of California, Berkeley, who led the research, said the mammoths' genomes "were falling apart right before they went extinct". This, she said, was the first case of "genomic meltdown" we have seen in a single species.

 

Woolly mammoths were once common in North America and Siberia. They were driven to extinction by environmental factors and possibly human hunting about 10,000 years ago. Small island populations clung on until about 4,000 years ago.

"There was this huge excess of what looked like bad mutations in the genome of the mammoth from this island," said Dr Rogers.

"We found these bad mutations were accumulating in the mammoth genome right before they went extinct."

 

Knowledge of the last days of the mammoth could help modern species on the brink of extinction, such as the panda, mountain gorilla and Indian elephant. The lesson from the woolly mammoth is that once numbers drop below a certain level, the population's genetic health may be beyond saving. Genetic testing could be one way to assess whether levels of genetic diversity in a species are enough to give it a chance of survival. A better option is to stop numbers falling too low.

 

"When you have these small populations for an extended period of time they can go into genomic meltdown, just like what we saw in the mammoth," said Dr Rogers.

 

"So if you can prevent these organisms ever being threatened or endangered then that will do a lot more to help prevent this type of genomic meltdown compared to if you have a small population and then bring it back up to larger numbers because it will still bear those signatures of this genomic meltdown."

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Birdsnap: Identifying a bird from a picture with artificial intelligence

Birdsnap: Identifying a bird from a picture with artificial intelligence | Amazing Science | Scoop.it
Birdsnap is a free electronic field guide covering 500 of the most common North American bird species, available as a web site or aniPhone app. Researchers from Columbia University and the University of Maryland developed Birdsnap using computer vision and machine learning to explore new ways of identifying bird species. Birdsnap automatically discovers visually similar species and makes visual suggestions for how they can be distinguished. In addition, Birdsnap uses visual recognition technology to allow users who upload bird images to search for visually similar species. Birdsnap estimates the likelihood of seeing each species at any location and time of year based on sightings records, and uses this likelihood both to produce a custom guide to local birds for each user and to improve the accuracy of visual recognition.

The genesis of Birdsnap (and its predecessors Leafnsap and Dogsnap) was the realization that many techniques used for face recognition developed by Peter Belhumeur (Columbia University) and David Jacobs(University of Maryland) could also be applied to automatic species identification. State-of-the-art face recognition algorithms rely on methods that find correspondences between comparable parts of different faces, so that, for example, a nose is compared to a nose, and an eye to an eye. In the same way, Birdsnap detects the parts of a bird, so that it can examine the visual similarity of comparable parts of the bird.Our first electronic field guide Leafsnap, produced in collaboration with the Smithsonian Institution, was launched in May 2011. This free iPhone app uses visual recognition software to help identify tree species from photographs of their leaves. Leafsnap currently includes the trees of the northeastern US and will soon grow to include the trees of the United Kingdom. Leafsnap has been downloaded by over a million users, and discussed extensively in the press (see Leafsnap.com, for more information). In 2012, we launched Dogsnap, an iPhone app that allows you to use visual recognition to help determine dog breeds. Dogsnap contains images and textual descriptions of over 150 breeds of dogs recognized by the American Kennel Club.

For their inspiration and advice on bird identification, we thank the UCSD Computer Vision group, especially Serge Belongie, Catherine Wah, and Grant Van Horn; the Caltech Computational Vision group, especially Pietro Perona, Peter Welinder, and Steve Branson; the alumni of these groups Ryan Farrell (now at BYU), Florian Schroff (at Google), and Takeshi Mita (at Toshiba); and the Visipedia effort.
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Lonesome George could be resurrected after cells are frozen by scientists

Lonesome George could be resurrected after cells are frozen by scientists | Amazing Science | Scoop.it

Lonesome George, the last of a now extinct type of giant tortoise from the Galapagos Islands, could be cloned after scientists have preserved some of his cells by cryogenically freezing them.

 

As the last of his kind, his life was a lonely one and his death brought the extinction of a lineage of animals that stretched back hundreds of thousands of years. Now Lonesome George, the last giant tortoise from Pinta Island in the Galapagos Islands who died just over a month ago, may be able to achieve in death what he could not in life – and produce an heir.

 

Scientists have cryogenically frozen tissue taken from the five foot long reptile just after his death in the hope that they may be able to resurrect the subspecies of Galapagos giant tortoise.

By using the same cloning techniques that created Dolly the Sheep, they believe it may be possible to one day bring the now extinct Pinta Island tortoises, or Chelonoidis nigra abingdonii as they are known scientifically, back to life.

 

It is a fitting legacy for an animal that had become a national icon in Ecuador, featuring on the country’s bank notes. His plight became a symbol for the efforts to conserve threatened species around the world, and attempts to find him a mate were followed by a global audience.

 

But with no female Pinta Island tortoises left alive, it was apparent he was doomed to spend the rest of his long life plodding slowly around his home alone until subspecies finally went extinct. The discovery sparked a huge effort to find him a mate so the animals might continue to survive. As the descendant of giant tortoises that arrived on Pinta Island around 300,000 years ago, it was unclear whether evolution during that time had left George unable to mate with related tortoises on nearby islands. Attempts to get George to mate with tortoises from neighbouring islands failed but last year hopes were raised when genetic testing revealed that his closest relatives were the giant tortoises of Espanola Island.

 

Research in to the cloning of endangered species is still at an early stage as most cloning to date has been achieved with animals whose biology is well understood such as cats, dogs and domestic farm animals like sheep and cows.

 

Recently, endangered black-footed cats were successfully cloned, while a wild ox called a gaur, wild cattle called banteng and a type of mountain goat called the Pyrenean ibex have been also been cloned, raising hopes for other endangered animals.

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Scientists isolate new antibodies to fight human respiratory syncytial virus (RSV)

Scientists isolate new antibodies to fight human respiratory syncytial virus (RSV) | Amazing Science | Scoop.it

Respiratory syncytial virus (RSV) is the most important cause of acute lower respiratory tract infection in very young children. Disease caused by RSV is very contagious and almost everyone is infected with RSV by the age of two years. Infections also reoccur throughout life. In the very young (from birth until the age of two years), the virus can cause severe respiratory tract disease characterized by bronchiolitis (inflammation of the bronchioles), pneumonia, and apnea (temporary cessation of breathing). One percent of RSV-infected children below the age of six months require hospitalization. In the USA, 100,000 children are hospitalized each year due to RSV, and 4500 children die from the infection. Worldwide, RSV causes 180,000 deaths each year. There is no vaccine and only one specific antiviral drug against RSV and supportive treatment is the only medical option for RSV-infected patients. 

 

RSV annually causes nearly 34 million illnesses in children under 5 years of age and can result in serious illness in both very young children and elderly people leading to hospitalization in up to 2% of cases. Despite intensive research and the virus' status as a major pathogen, current methods of treatment rely almost exclusively on supportive care. With the goal of developing a new therapy to fight this disease, Prof. Xavier Saelens (VIB-UGent) and his team developed Nanobodies® that target the protein that the virus needs to enter lung cells. The researchers showed that these Nanobodies® neutralized the virus in laboratory assays as well as in animals.

 

The approach hinges on the use of single-domain antibodies, also known as Nanobodies®, which target and neutralize a vital protein in the virus, rendering it unable to enter lung cells. The research, published in the leading scientific journal Nature Communications, elucidates how these Nanobodies® interact with and neutralize the virus and demonstrates their ability to successfully protect mice from RSV infection and related inflammation.

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chirurgien-visage-tunisie's curator insight, February 21, 4:35 AM

Chirurgies esthétique Tunisie est ce que vraiment des avancées dans la médecine ou un marketing réussi ?

La chirurgie esthétique en Tunisie ne cesse d'avancer et pousser les autres branches de la médecine. Cela est du essentiellement à des prix pas chers de la chirurgie visage, corps et silhouette, puis vient l'expérience des chirurgiens Tunisiens qui existent sur le domaine. Cela a encouragé des touristes à venir en Tunisie afin de programmer des chirurgies plus complexes comme la liposuccion, abdominoplastie, bypass gastrique, sleeve gastrique anneau gastrique et d'autres chirurgies générales.

chirurgien-visage-tunisie's comment, February 21, 4:38 AM
Nous encourageons toutes activités scientifiques et médicales en Tunisie. Contactez nous http://www.medespoir.ch/devis.php
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How Life (and Death) Spring From Disorder

How Life (and Death) Spring From Disorder | Amazing Science | Scoop.it

Life was long thought to obey its own set of rules. But as simple systems show signs of lifelike behavior, scientists are arguing about whether this apparent complexity is all a consequence of thermodynamics.

 

Living organisms seem rather like Maxwell’s demon. Whereas a beaker full of reacting chemicals will eventually expend its energy and fall into boring stasis and equilibrium, living systems have collectively been avoiding the lifeless equilibrium state since the origin of life about three and a half billion years ago. They harvest energy from their surroundings to sustain this nonequilibrium state, and they do it with “intention.” Even simple bacteria move with “purpose” toward sources of heat and nutrition. In his 1944 bookWhat is Life?, the physicist Erwin Schrödinger expressed this by saying that living organisms feed on “negative entropy.”

 

They achieve it, Schrödinger said, by capturing and storing information. Some of that information is encoded in their genes and passed on from one generation to the next: a set of instructions for reaping negative entropy. Schrödinger didn’t know where the information is kept or how it is encoded, but his intuition that it is written into what he called an “aperiodic crystal”inspired Francis Crick, himself trained as a physicist, and James Watson when in 1953 they figured out how genetic information can be encoded in the molecular structure of the DNA molecule.

 

A genome, then, is at least in part a record of the useful knowledge that has enabled an organism’s ancestors — right back to the distant past — to survive on our planet. According to David Wolpert, a mathematician and physicist at the Santa Fe Institute who convened the recent workshop, and his colleagueArtemy Kolchinsky, the key point is that well-adapted organisms are correlated with that environment. If a bacterium swims dependably toward the left or the right when there is a food source in that direction, it is better adapted, and will flourish more, than one  that swims in random directions and so only finds the food by chance. A correlation between the state of the organism and that of its environment implies that they share information in common. Wolpert and Kolchinsky say that it’s this information that helps the organism stay out of equilibrium — because, like Maxwell’s demon, it can then tailor its behavior to extract work from fluctuations in its surroundings. If it did not acquire this information, the organism would gradually revert to equilibrium: It would die.

 

Looked at this way, life can be considered as a computation that aims to optimize the storage and use of meaningful information. And life turns out to be extremely good at it. Landauer’s resolution of the conundrum of Maxwell’s demon set an absolute lower limit on the amount of energy a finite-memory computation requires: namely, the energetic cost of forgetting. The best computers today are far, far more wasteful of energy than that, typically consuming and dissipating more than a million times more. But according to Wolpert, “a very conservative estimate of the thermodynamic efficiency of the total computation done by a cell is that it is only 10 or so times more than the Landauer limit.”

The implication, he said, is that “natural selection has been hugely concerned with minimizing the thermodynamic cost of computation. It will do all it can to reduce the total amount of computation a cell must perform.” In other words, biology (possibly excepting ourselves) seems to take great care not to overthink the problem of survival. This issue of the costs and benefits of computing one’s way through life, he said, has been largely overlooked in biology so far.

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Rising Back To Life: Cell Death Might Be Reversible

Rising Back To Life: Cell Death Might Be Reversible | Amazing Science | Scoop.it

A mysterious cell process named "anastasis" (Greek for "rising to life") challenges our idea of life being a linear march towards death, and suggests that cell death can actually be reversed under certain conditions—essentially allowing cells to un-die.

 

Even as the cell is shrivelling up in response to radiation, toxins, or other stresses, it can in some cases undo the dying process and repair itself if the stress is taken away before the cell is completely gone, said cell biologist Denise Montell of the University of California, Santa Barbara.

 

"In the field of people studying apoptosis—this programmed cell suicide mechanism—it has been a tenet in that field that once cells trigger this death process, it's irreversible," Montell told me over the phone. Her research, beginning with a paper published by the journal Molecular Biology of the Cell in 2012, shows otherwise.

 

Montell's lab wants to see if they can use anastasis to salvage hard-to-replace cells in the human body, which could be important in treating ischemia or heart attacks. But it could also provide an accidental, chilling glimpse into the hows and whys of cancer.

 

Every day, the billions of cells in our bodies actively decide whether they should continue to live, or die. Damaged cells must die—otherwise we might get cancer or other diseases—through programmed cell death processes, the most famous of which is apoptosis (from the Greek for "falling off").

 

"There are many cells that we don't want to die. This is particularly true for the neurons in our brain, which have to last our whole life, or the cells for our heart," Montell explained. A careful balance must be struck: if too many cells die we'd develop diseases like Alzheimer's or Parkinson's, a hallmark of which is neuronal cell death.

 

Once apoptosis begins, a critical molecule called executioner caspase is activated within the cell. It does exactly what it sounds like. The caspase goes around the cell, dicing up cell parts, and the cell starts to shrivel up. "Eventually it will break into little pieces, and then other cells come and gobble up the little pieces," she said.

 

Montell began her research on anastasis years ago at John Hopkins University, where a student applied to join her lab as a postdoc after discovering the death-reversal process during his graduate work in Hong Kong. Montell credits this student—Hogan Tang—with discovering anastasis, which was aptly named with the help of classics scholars, she said.

 

The next step was to test it on mammalian and fruit fly cells. Montell told Tang as much when he came over to visit her in 2008, and brought up what he'd observed. She was skeptical. But after several months of questioning, Tang joined her lab and they began to seriously pursue the discovery.

 

So far, they've seen anastasis in 12 different types of mammalian cells. The fact that it can be observed in human and fruit fly cells, Montell said, suggests that anastasis is an incredibly ancient process shared by a common ancestor that must date back millions of years.


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New machine-learning algorithms may revolutionize drug discovery — and our understanding of life

New machine-learning algorithms may revolutionize drug discovery — and our understanding of life | Amazing Science | Scoop.it

A new set of machine-learning algorithms developed by researchers at the University of Toronto Scarborough can generate 3D structures of nanoscale protein molecules that could not be achieved in the past. The algorithms may revolutionize the development of new drug therapies for a range of diseases and may even lead to better understand how life works at the atomic level, the researchers say.

 

Drugs work by binding to a specific protein molecule and changing the protein’s 3D shape, which alters the way the drug works once inside the body. The ideal drug is designed in a shape that will only bind to a specific protein or group of proteins that are involved in a disease, while eliminating side effects that occur when drugs bind to other proteins in the body.

 

Since proteins are tiny — about 1 to 100 nanometers — even smaller than the shortest wavelength of visible light, they can’t be seen directly without using sophisticated techniques like electron cryomicroscopy (cryo-EM). Cryo-EM uses high-power microscopes to take tens of thousands of low-resolution images of a frozen protein sample from different positions.

The computational problem is to then piece together the correct high-resolution 3D structure from these 2D images.

 

Existing techniques take several days or even weeks to generate a 3D structure on a cluster of computers, requiring as much as 500,000 CPU hours, according to the researchers. Also, existing techniques often generate incorrect structures unless an expert user provides an accurate guess of the molecule being studied.

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Extinct tortoise species with mostly intact DNA from a water-filled limestone sinkhole

Extinct tortoise species with mostly intact DNA from a water-filled limestone sinkhole | Amazing Science | Scoop.it

An extinct tortoise species that accidentally tumbled into a water-filled limestone sinkhole in the Bahamas about 1,000 years ago has finally made its way out, with much of its DNA intact.

As the first sample of ancient DNA retrieved from an extinct tropical species, this genetic material could help provide insights into the history of the Caribbean tropics and the reptiles that dominated them, said University of Florida ornithologist David Steadman. It could also offer clues to the region’s future, as the tropics undergo significant transformation due to climate change.

 

“This is the first time anyone has been able to put a tropical species into an evolutionary context with molecular data,” said Steadman, an ornithology curator at the Florida Museum of Natural History on the UF campus and co-author of the study discussing the finding. “And being able to fit together the tortoise’s evolutionary history together will help us better understand today’s tropical species, many of which are endangered.”

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Deep-Sea Mining: Undersea Robot to Hunt for Strange Life in the Depth of the Pacific

Deep-Sea Mining: Undersea Robot to Hunt for Strange Life in the Depth of the Pacific | Amazing Science | Scoop.it
The research ship Okeanos Explorer is sending an ROV into the depths of the Pacific Ocean, seeking out exotic sea animals and other curiosities. And, you can watch it live online.

 

Armchair oceanographers, take note: This week, the research ship Okeanos Explorer will send a remotely operated vehicle into the depths of the Pacific Ocean, seeking out exotic sea animals like the "walking" fish called a sea toad and other curiosities. And, you can have a front-row seat.

 

The ROV, called Deep Discoverer, will reach depths of 3.7 miles (6,000 meters) beneath the sea's surface. Its trip is scheduled to begin Thursday (Feb. 16), and you can watch it unfold online.

This expedition, which will run through September, is part of NOAA's CAPSTONE, or Campaign to Address Pacific monument Science, Technology, and Ocean Needs.

 

The project, in its third and final year, is aimed at collecting data from the deep ocean within marine-protected areas in the central and western Pacific Ocean, according to NOAA. The information will not only shed light on largely unexplored areas; it will also help others to make informed decisions regarding management of the protected areas and on the issue of deep-sea mining.

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"ON delayed" myopia cell discovered in retina

"ON delayed" myopia cell discovered in retina | Amazing Science | Scoop.it

Scientists have discovered a cell in the retina that may cause myopia when it dysfunctions. The dysfunction may be linked to the amount of time a child spends indoors and away from natural light.  

 

“This discovery could lead to a new therapeutic target to control myopia,” said Greg Schwartz, lead investigator and assistant professor of ophthalmology at Northwestern University Feinberg School of Medicine. 

 

More than a billion people in the world have myopia, whose incidence is rising and is linked to how much time people spend indoors as children.

 

The newly discovered retinal cell — which is highly sensitive to light — controls how the eye grows and develops. If the cell instructs the eye to grow too long, images fail to be focused on the retina, causing nearsighted vision and a lifetime of corrective glasses or contact lenses. 

 

“The eye needs to stop growing at precisely the right time during childhood,” Schwartz said. It has long been long known the retina contains a signal to focus the image in the eye, and this signal is important for properly regulating eye growth during childhood. “But for years no one knew what cell carried the signal,” Schwartz said. “We potentially found the key missing link, which is the cell that actually does that task and the neural circuit that enables this important visual function.”

 

Schwartz named the cell, “ON Delayed,” in reference to its slow responses to lights becoming brighter. The cell was unique among many other cell types tested in its exquisite sensitivity to whether an image was in focus. He described the neural circuit as the diagram that reveals how this cell is wired to other cells in the retina to acquire this unique sensitivity.

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Wild Birds Learn to Recognize Individual Humans They Hate

Wild Birds Learn to Recognize Individual Humans They Hate | Amazing Science | Scoop.it

Antarctic seabirds called skuas are so clever that they can recognize individual humans after seeing them only a few times. Some Korean researchers discovered this by messing with the birds’ nests and then waiting to get attacked. They’re either very brave or have never watched The Birds.

 

The study took place on Antarctica’s King George Island. The animals here didn’t evolve around humans. People have only been making appearances on the island since the 1950s or so. Today 10 countries have research stations on the island. Korea Polar Research Institute scientist Won Young Lee and his coauthors study brown skuas here, which are like big, dark-colored gulls.

 

In the winter of 2014–2015, researchers visited skua nests once a week to check on their eggs and chicks. They suspected that the birds could recognize them, and were unhappy about humans poking at their nests. If a skua wants you to go away, it will give not-so-subtle hints like attacking your head.

 

So the researchers set up an experiment. Starting in the fourth week of their study, two researchers visited each nest at a time. One of them, the “intruder,” had checked on the nest in previous weeks. The other, “neutral” researcher had never been to the nest before. As they approached the nest, the researchers recorded how close they could get before the birds attacked. Then they split up and walked in opposite directions, observing which person the birds chased after.

 

As the weeks went on, skuas attacked from greater distances. But they didn’t attack just anybody. All seven of the nesting pairs directed their attacks at the known intruder. The birds “reacted very aggressively” after five visits, the authors write, including kicking intruders in the head. They ignored the neutral humans.

Even though the researcher pairs wore identical clothing for their experiments, the skuas had no trouble spotting people who had fiddled with their nests in the past. The researchers don’t think the birds were using smell to tell them apart, since the site is windy. More likely, the birds relied on human facial features and body postures.

 

This is especially impressive since the birds evolved without ever seeing a human. There’s no reason they should have a natural ability to recognize us. Two other local bird species, sheathbills and Antarctic terns, don’t seem to discriminate between people.

 

The scientists chalk it up to “high cognitive abilities” on the part of brown skuas. In other words, they may just be especially smart. This makes sense; the birds are predators that have to be flexible to find their prey. Brown skuas have been seen chasing other large birds and taking their food. They’ll even steal drops of breast milk from nursing elephant seals. This is a bird you don’t want to cross—and after you do, you might want to wear a mask.

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