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Skeptical Debunker

Does promiscuity prevent extinction? - 0 views

  • Known as 'polyandry' among scientists, the phenomenon of females having multiple mates is shared across most animal species, from insects to mammals. This study suggests that polyandry reduces the risk of populations becoming extinct because of all-female broods being born. This can sometimes occur as a result of a sex-ratio distortion (SR) chromosome, which results in all of the Y chromosome 'male' sperm being killed before fertilisation. The all-female offspring will carry the SR chromosome, which will be passed on to their sons in turn resulting in more all-female broods. Eventually there will be no males and the population will die out. For this study, the scientists worked with the fruitfly Drosophila pseudoobscura. They gave some populations the opportunity to mate naturally, meaning that the females had multiple partners. The others were restricted to having one mate each. They bred several generations of these populations, so they could see how each fared over time. Over fifteen generations, five of the twelve populations that had been monogamous became extinct as a result of males dying out. The SR chromosome was far less prevalent in the populations in which females had the opportunity to have multiple mates and none of these populations became extinct. The study shows how having multiple mates can suppress the spread of the SR chromosome, making all-female broods a rarity. This is because males that carry the SR chromosome produce only half as many sperm as normal males. When a female mates with multiple males, their sperm will compete to fertilise her eggs. The few sperm produced by males carrying the SR chromosome are out-competed by the sperm from normal males, and the SR chromosome cannot spread.
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    Promiscuous females may be the key to a species' survival, according to new research by the Universities of Exeter and Liverpool. Published today (25 February) in Current Biology, the study could solve the mystery of why females of most species have multiple mates, despite this being more risky for the individual.
Walid Damouny

UN: Fight climate change with free condoms - 0 views

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    "(AP) -- The battle against global warming could be helped if the world slowed population growth by making free condoms and family planning advice more widely available, the U.N. Population Fund said Wednesday."
Erich Feldmeier

Stephen Giovannoni: wissenschaft.de - Mikroskopischer Weltkrieg - 0 views

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    ""Die Viren scheinen genauso häufig zu sein wie die SAR1-Bakterien selbst", sagte Giovannoni. Sie töten ständig Unmengen von ihnen. Offenbar sind die SAR11-Bakterien aber in der Lage, sich an die Bedrohung anzupassen und dadurch ihre Population stabil zu halten, sagen die Forscher. Es gibt also demnach ein ständiges Wettrüsten zwischen den Meeresbakterien und ihren viralen Feinden. Das Wissen über dieses Zusammenspiel sei ein wichtiges Puzzleteil beim Verständnis der Stoffkreisläufe im Ozean. Das Gleichgewicht im Kampf zwischen SAR11-Bakterien und Pelagiphagen beeinflusst letztendlich alles Leben auf unserem Planeten, resümieren die Wissenschaftler. Stephen Giovannoni (Oregon State University) et al.: Nature, doi:10.1038/nature11921 "
Erich Feldmeier

Jeremy Ginsberg: Grippe, Detecting influenza epidemics using search engine query data :... - 0 views

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    "Seasonal influenza epidemics are a major public health concern, causing tens of millions of respiratory illnesses and 250,000 to 500,000 deaths worldwide each year1. In addition to seasonal influenza, a new strain of influenza virus against which no previous immunity exists and that demonstrates human-to-human transmission could result in a pandemic with millions of fatalities2. Early detection of disease activity, when followed by a rapid response, can reduce the impact of both seasonal and pandemic influenza3, 4. One way to improve early detection is to monitor health-seeking behaviour in the form of queries to online search engines, which are submitted by millions of users around the world each day. Here we present a method of analysing large numbers of Google search queries to track influenza-like illness in a population."
Janos Haits

Home - 0 views

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    The Health System Measurement Project tracks government data on critical U.S. health system indicators. The website presents national trend data as well as detailed views broken out by population characteristics such as age, sex, income level, and insurance coverage status.
Ivan Pavlov

New findings challenge assumptions about origins of life - 0 views

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    Our genetic code is translated by two super-families of modern-day enzymes. Carter's research team created and superimposed digital three-dimensional versions of the two super-families to see how their structures aligned. Carter found that all the enzymes have virtually identical cores that can be extracted to produce "molecular fossils" he calls Urzymes-Ur meaning earliest or original. The other parts, he said, are variations that were introduced later, as evolution unfolded. These two Urzymes are as close as scientists have gotten to the actual ancient enzymes that would have populated the Earth billions of years ago.
Ivan Pavlov

Cryptic new species of wild cat identified in Brazil - 0 views

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    Scientists had thought that there was a single species of housecat-sized Brazilian tigrina. However, the molecular data now show that tigrina populations in northeastern versus southern Brazil are completely separate, with no evidence of interbreeding between them. As such, they are best described as two distinct species.
Erich Feldmeier

@biogarage Traditional Chinese medicine #TCM origins: Mao invented it but didn't believ... - 0 views

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    "Mao's support of Chinese medicine was inspired by political necessity. In a 1950 speech (unwittingly echoed by the Senate's concerns about "providing health care to underserved populations"), he said: Our nation's health work teams are large. They have to concern themselves with over 500 million people [including the] young, old, and ill. … At present, doctors of Western medicine are few, and thus the broad masses of the people, and in particular the peasants, rely on Chinese medicine to treat illness. Therefore, we must strive for the complete unification of Chinese medicine"
Janos Haits

SciVal Experts | SciVal - 0 views

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    SciVal® Experts is an expertise profiling and research networking tool that helps users find researchers with specific areas of expertise for collaboration and enables researchers in your institution to demonstrate their activities to the global research community. Pre-populated with deep publication histories from Elsevier's Scopus® - the world's largest abstract and citation database of peer-reviewed literature - SciVal Experts makes it easier to find experts and form teams within your institution and across organizations.
Janos Haits

WWF Species Tracker - All species - - 0 views

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    "WWF supports research on wildlife populations throughout the Arctic and around the world. Using radio devices, which transmit location data by satellite, researchers can follow individual animals to learn more about their habitats, behaviour and migration patterns. The researchers share this data with WWF regularly, so check back often to see where the animals are going!"
thinkahol *

Why More Equality? | The Equality Trust - 0 views

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    Why More Equality? Our thirty years research shows that: 1) In rich countries, a smaller gap between rich and poor means a happier, healthier, and more successful population. Just look at the US, the UK, Portugal, and New Zealand in the top right of this graph, doing much worse than Japan, Sweden or Norway in the bottom left.
Skeptical Debunker

Flightless mosquitoes developed to help control dengue fever - 0 views

  • Dengue fever causes severe flulike symptoms and is among the world's most pressing public health issues. There are 50 million to 100 million cases per year, and nearly 40 percent of the global population is at risk. The dengue virus is spread through the bite of infected female Aedes aegypti mosquitoes, and there is no vaccine or treatment. UCI researchers and colleagues from Oxitec Ltd. and the University of Oxford created the new breed. Flightless females are expected to die quickly in the wild, curtailing the number of mosquitoes and reducing - or even eliminating - dengue transmission. Males of the strain can fly but do not bite or convey disease. When genetically altered male mosquitoes mate with wild females and pass on their genes, females of the next generation are unable to fly. Scientists estimate that if released, the new breed could sustainably suppress the native mosquito population in six to nine months. The approach offers a safe, efficient alternative to harmful insecticides.
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    A new strain of mosquitoes in which females cannot fly may help curb the transmission of dengue fever, according to UC Irvine and British scientists. Great idea or frankensketter?
Skeptical Debunker

Tally of Antarctic Sealife Sheds Light on Changing Climate - 0 views

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    More than 6,000 different species living on the sea-floor have been identified so far and more than half of these are unique to the icy continent. A combination of long-term monitoring studies, newly gathered information on the marine life distribution and global ocean warming models, enable the scientists to identify Antarctica's marine "biodiversity hotspots". Researcher Griffiths describes how krill populations (the shrimp-like invertebrates eaten by penguins, whales and seals) are reducing as a result of a decrease in sea-ice cover. A much smaller crustacean (copepods) is dominating the area once occupied by them. This shifts the balance of the food web to favour predators, like jellyfish, that are not eaten by penguins and other Southern Ocean higher predators. Sea-ice reduction is also affecting penguins that breed on the ice.
thinkahol *

YouTube - Sam Harris SALT - 2 views

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    December 9th, 02005 - Sam Harris"The View From The End Of The World"This is an audio only presentation. This talk took place in the Conference Center Golden Gate Room, San Francisco. Quote: With gentle demeanor and tight argument, Sam Harris carried an overflow audience into the core of one of the crucial issues of our time: What makes some religions lethal? How do they employ aggressive irrationality to justify threatening and controlling non-believers as well as believers? What should be our response? Harris began with Christianity. In the US, Christians use irrational arguments about a soul in the 150 cells of a 3-day old human embryo to block stem cell research that might alleviate the suffering of millions. In Africa, Catholic doctrine uses tortured logic to actively discourage the use of condoms in countries ravaged by AIDS. "This is genocidal stupidity," Harris said. Faith trumps rational argument. Common-sense ethical intuition is blinded by religious metaphysics. In the US, 22% of the population are CERTAIN that Jesus is coming back in the next 50 years, and another 22% think that it's likely. The good news of Christ's return, though, can only occur following desperately bad news. Mushroom clouds would be welcomed. "End time thinking," Harris said, "is fundamentally hostile to creating a sustainable future." Harris was particularly critical of religious moderates who give cover to the fundamentalists by not challenging them. The moderates say that all is justified because religion gives people meaning in their life. "But what would they say to a guy who believes there's a diamond the size of a refrigerator buried in his backyard? The guy digs out there every Sunday with his family, cherishing the meaningthe quest gives them." "I've read the books," Harris said. "God is not a moderate." The Bible gives strict instructions to kill various kinds of sinners, and their relatives, and on occasion their entire towns. Yet slavery is challenged nowhere in the New or
thinkahol *

Nuclear radiation affects sex of babies, study suggests - 0 views

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    ScienceDaily (May 27, 2011) - Ionizing radiation is not without danger to human populations. Indeed, exposure to nuclear radiation leads to an increase in male births relative to female births, according to a new study by Hagen Scherb and Kristina Voigt from the Helmholtz Zentrum München.
thinkahol *

Minority rules: Scientists discover tipping point for the spread of ideas - 1 views

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    ScienceDaily (July 26, 2011) - Scientists at Rensselaer Polytechnic Institute have found that when just 10 percent of the population holds an unshakable belief, their belief will always be adopted by the majority of the society. The scientists, who are members of the Social Cognitive Networks Academic Research Center (SCNARC) at Rensselaer, used computational and analytical methods to discover the tipping point where a minority belief becomes the majority opinion. The finding has implications for the study and influence of societal interactions ranging from the spread of innovations to the movement of political ideals.
thinkahol *

Dr. Daniel G. Nocera - YouTube - 0 views

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    The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b
thinkahol *

Sex and the Red Queen hypothesis | KurzweilAI - 1 views

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    The hypothesis suggests that sexual reproduction via cross-fertilization keeps host populations one evolutionary step ahead of the parasites, which are frantically co-evolving to infect them. So both hosts and parasites are running (evolving) as fast as they can just to stay in the same place.
anonymous

Learn More About Dairy Farming - 1 views

There is so much about dairy farming that is not known by the common public. With the majority of people going back to organic farming and natural products, this kind of dairy products has a lot of...

organic farming dairy Mahendra The Effect science research trivedi

started by anonymous on 22 Dec 14 no follow-up yet
Erich Feldmeier

@meise3 @5SeenGeno #Biene Die AG Toleranzzucht: AGT - Varroa - 0 views

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    "Die AG Toleranzzucht Nur eine effektive Selektion in großer Population ermöglicht nachhaltige Zuchterfolge! Zu diesem Zweck haben sich viele Züchter und Prüfer in der AG Toleranzzucht (AGT) zusammengeschlossen. Gemeinsam verfolgen wir das Ziel, leistungsfähige Honigbienen mit hoher Widerstandskraft gegen die Varroose zu züchten."
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