Fuente: SfAM news
Expuesto el: viernes, 06 de septiembre de 2013 15:56
Autor: SfAM news
Asunto: At least 32,000 undiscovered viruses may be circulating in mammals
Researchers from the Center for Infection and Immunity at Columbia University's Mailman School of Public Health in the US, have estimated that there may be at least 32,000 viruses circulating in mammals which are awaiting discovery. |
Fuente: Research News - Research Portal - Research
Expuesto el: martes, 09 de julio de 2013 17:19
Autor: Research News - Research Portal - Research
Asunto: Mussels organise themselves like molecules in materials
Mussels within mussel beds form a pattern resembling the way molecules and atoms are organised in materials such as bronze, steel or rubber. This means it is possible to explain their behaviour on the basis of the same mathematical model. Patterns in dynamic systemsEcologists and mathematicians at the Royal Netherlands Institute for Sea Research (NIOZ) and the universities of Utrecht and Leiden revealed their findings in Proceedings of the National Academy of Science (PNAS) on 1 July. Mathematicians Arjen Doelman and Vivi Rottschäfer from Leiden University, who were involved in the project, are specialists in describing pattern formation in dynamic systems. These mussels form a mathematical pattern Bronze, steel and rubberMussels organise themselves into a pattern known as 'phase separation': molecules and atoms of different types separate out to form spatial patterns. Phase separation is a physical process which gives alloys such as bronze and steel, and polymers such as rubber, their robustness. It can be described by means of a mathematical model (the Cahn-Hilliard model). Animal behaviourEcologists are familiar with the phenomenon of aggregation and pattern formation by animals in motion, but until now they based this fascinating phenomenon of self-organisation on the spatial differences in the growth or death of organisms, rather than on the behaviour of the animals themselves. Mathematical modelsProfessor Arjen Doelman, mathematician at Leiden University, who was involved in the project together with colleague Vivi Rottschäfer, is rarely surprised by such wonders of nature. He believes that the same mathematical models can be applied to many different natural phenomena. His own PhD research, which was inspired by the desire to understand water currents, later proved to be significant for the understanding of superconductivity. And a mathematical description of a chemical reaction was recorded in the same way by an ecologist 20 years later. Cross pollination at its bestDoelman: 'This type of research is cross pollination at its best. We discover a new mathematical angle, and ecologists are able to look at nature in a different way.' He also found it 'really fascinating to observe' the speed and the precision with which the mussels formed the pattern. DesertificationDoelman often works with ecologists, and one example of his studies is the relation between vegetation patterns and desertification. He is also fascinated by phytoplankton, that organise themselves in mysterious concentrations. Doelman: 'As phytoplankton absorb 50% of CO2 in the atmosphere, they have a crucial role in climates. It's therefore very important that we fully understand what is going on here.' (9 July 2013) ArticlePhase separation explains a new class of self-organized spatial patterns in ecological systems. See alsoFundamentals of Science is one of the six key themes for research at Leiden University. Last Modified: 10-07-2013
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Fuente: News archive - University of Exeter
Expuesto el: jueves, 04 de julio de 2013 0:21
Autor: News archive - University of Exeter
Asunto: New research by an international team of researchers has revealed the previously unidentified role that fish play in the production of sediments in the world's oceans.
New research by an international team of researchers has revealed the previously unidentified role that fish play in the production of sediments in the world's oceans. |
Fuente: News archive - University of Exeter
Expuesto el: jueves, 04 de julio de 2013 0:21
Autor: News archive - University of Exeter
Asunto: The mystery of how a butterfly has changed its wing patterns to mimic neighbouring species and avoid being eaten by birds has been solved by a team of scientists.
The mystery of how a butterfly has changed its wing patterns to mimic neighbouring species and avoid being eaten by birds has been solved by a team of scientists. |
Fuente: Research News - Research Portal - Research
Expuesto el: martes, 09 de julio de 2013 17:19
Autor: Research News - Research Portal - Research
Asunto: Mussels organise themselves like molecules in materials
Mussels within mussel beds form a pattern resembling the way molecules and atoms are organised in materials such as bronze, steel or rubber. This means it is possible to explain their behaviour on the basis of the same mathematical model. Patterns in dynamic systemsEcologists and mathematicians at the Royal Netherlands Institute for Sea Research (NIOZ) and the universities of Utrecht and Leiden revealed their findings in Proceedings of the National Academy of Science (PNAS) on 1 July. Mathematicians Arjen Doelman and Vivi Rottschäfer from Leiden University, who were involved in the project, are specialists in describing pattern formation in dynamic systems. These mussels form a mathematical pattern Bronze, steel and rubberMussels organise themselves into a pattern known as 'phase separation': molecules and atoms of different types separate out to form spatial patterns. Phase separation is a physical process which gives alloys such as bronze and steel, and polymers such as rubber, their robustness. It can be described by means of a mathematical model (the Cahn-Hilliard model). Animal behaviourEcologists are familiar with the phenomenon of aggregation and pattern formation by animals in motion, but until now they based this fascinating phenomenon of self-organisation on the spatial differences in the growth or death of organisms, rather than on the behaviour of the animals themselves. Mathematical modelsProfessor Arjen Doelman, mathematician at Leiden University, who was involved in the project together with colleague Vivi Rottschäfer, is rarely surprised by such wonders of nature. He believes that the same mathematical models can be applied to many different natural phenomena. His own PhD research, which was inspired by the desire to understand water currents, later proved to be significant for the understanding of superconductivity. And a mathematical description of a chemical reaction was recorded in the same way by an ecologist 20 years later. Cross pollination at its bestDoelman: 'This type of research is cross pollination at its best. We discover a new mathematical angle, and ecologists are able to look at nature in a different way.' He also found it 'really fascinating to observe' the speed and the precision with which the mussels formed the pattern. DesertificationDoelman often works with ecologists, and one example of his studies is the relation between vegetation patterns and desertification. He is also fascinated by phytoplankton, that organise themselves in mysterious concentrations. Doelman: 'As phytoplankton absorb 50% of CO2 in the atmosphere, they have a crucial role in climates. It's therefore very important that we fully understand what is going on here.' (9 July 2013) ArticlePhase separation explains a new class of self-organized spatial patterns in ecological systems. See alsoFundamentals of Science is one of the six key themes for research at Leiden University. Last Modified: 10-07-2013
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Fuente: RSS for www-mc1.cardiff.ac.uk
Expuesto el: jueves, 18 de julio de 2013 1:00
Autor: RSS for www-mc1.cardiff.ac.uk
Asunto: Secrets of bee honeycombs revealed
The mystery of the hexagonal shape of honeycomb cells has been revealed by simple mechanics. The honeybee comb is a widely studied natural cellular structure. The rounded hexagonal shape of its cells has intrigued natural scientists and philosophers for millennia. They have suggested many explanations some of which would need the bees to have an uncanny ability ("forethought" according to Pappus of Alexandria in 4 AD) to perform mathematical calculations or the magical quality to measure lengths and angles. Now research from Cardiff University's School of Engineering, published in Journal of the Royal Society Interface, has found that the cells in a natural honeybee comb have a circular shape at "birth" but quickly transform into the familiar rounded hexagonal shape while the comb is being built. The research led by Professor Bhushan Karihaloo, Cardiff School of Engineering with co-authors from Beijing Institute of Technology and Peking University also shows how this transformation takes place. "People have always speculated how bees have formed these honeycombs," said Professor Karihaloo "There have been some incredible, esoteric, even bizarre explanations; they believed the bees had an uncanny ability to measure angles. But it's actually much more straight-forward." The answer, according to a new study, is that the cells do not start out as hexagons but as circles. Darwin in fact had suggested this but he had no supporting evidence. They gradually form into hexagons by a flow of the wax, which is turned semi-molten by the heat from specialist "heater" worker bees. At approx 45°C, the wax starts to flow slowly as an elastic liquid. The wax, softened by the heat, then gets pulled into hexagonal cells by surface tension at the junctions where three walls meet.
Despite solving the mystery the researchers pay tribute to the bees, writing in the study: ""We cannot... ignore, nor can we not marvel at the role played by the bees in this process by heating, kneading and thinning the wax exactly where needed." The research has attracted international media coverage including Nature, Discovery News, Livescience (New York); ABC Science and the Huffington Post. Related links(2nd Photo caption: Italian honeybee (Apis mellifera Ligustica) comb cell at "birth" (a), and at 2-day age (b), Scale bar is 2 mm.)
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Fuente: Research
Expuesto el: viernes, 28 de junio de 2013 20:08
Autor: Research
Asunto: Lemurs' group size predicts social intelligence
