| Fertility study on mice eggs raise hope for older mothers UK research identifying loss of key protein in mice eggs is seen as a breakthrough that may help prevent birth defectsScientists have made a breakthrough in understanding why older women become less fertile, suffer a miscarriage or have a baby with Down's syndrome.The discovery could ultimately lead to treatments that would increase the chances of a successful pregnancy for growing numbers of would-be mothers in their late 30s and early 40s.Researchers led by Dr Mary Herbert, an expert in reproductive biology at Newcastle University's Institute for Ageing and Health, have identified why some older women produce abnormal eggs, according to findings published in the journal Current Biology.It has been known for a long time that would-be mothers who are nearing the end of their fertility are at higher risk than usual of having eggs that are affected by chromosomal abnormalities, but the underlying cause has been unclear.The new study has identified problems arising from a woman's declining stock of proteins called Cohesins, which act as binding agents to hold chromosomes together by keeping them inside a ring. They are vital to ensure that chromosomes split evenly when cells divide.Women's supplies of Cohesins fall as they age, Herbert and her colleagues discovered. Tests on eggs taken from both young and old mice indicated that the amount of Cohesins in women's bodies declines after their mid-30s.When that happens it means that chromosomes are less tightly held together and they are therefore more likely to result in defective eggs, which can cause problems such as miscarriage and Down's syndrome.Every cell in the human body, apart from eggs and sperm, contains two copies of each of the body's 23 chromosomes. Sperm and eggs must lose one copy each as they prepare for fertilisation. That process involves a complicated form of cell division.This problem is compounded with eggs, because the attachments that hold chromosomes together have to be maintained by Cohesins until the egg divides just before ovulation.When Herbert's team studied chromosomes during division in the egg, they found that the lower levels of Cohesin in eggs in older females led to some chromosomes becoming trapped and unable to divide properly."Reproductive fitness in women declines dramatically from the mid-30s onwards. Our findings point to Cohesin being a major culprit in this", said Herbert. More work was needed to understand why Cohesin declines over women's reproductive years, and such knowledge could lead to ways being developed to stop that loss from occurring.Dr Peter Bowen-Simpkins, the medical director of the London Women's Clinic network of private fertility clinics and spokesman for the Royal College of Obstetricians and Gynaecologists, said the study was "very exciting" and could lead to real improvements in older women's chances of having children."This breakthrough could mean the difference between success and failure – them having a baby or not – for the fast-growing number of women who are trying to conceive after their late 30s," he added.ReproductionBiologyFertility problemsGeneticsDenis Campbellguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Podcast: What the brain can and can't do Professor Barry Smith, director of the Institute of Philosophy at the University of London explores what happens inside our heads when we recognise a friend or reach for a cup of coffee.Professor Smith has just made a series of programmes for the BBC World Service called The Mysteries of the Brain, which starts today. So that's what the brain can do. We also look at what it can't do ... We dial up Professor Russell Stannard, emeritus professor of physics at the Open University. He thinks humans are fast approaching the end of what it is possible for us to know and understand. Caspar Llewellyn-Smith asks him about some of the themes in his new book, The End of Discovery. Check out our shiny new science front page and meet our crack team of science bloggers:The Lay Scientist by Martin RobbinsLife and Physics by Jon ButterworthPunctuated Equilibrium by GrrlScientistPolitical Science by Evan Harris Follow the podcast on our Science Weekly Twitter feed and receive updates on all breaking science news stories from Guardian Science. Email scienceweeklypodcast@gmail.com. Join our Facebook group. Listen back through our archive.Subscribe free via iTunes to ensure every episode gets delivered. (Here is the non-iTunes URL feed).Caspar Llewellyn SmithAlok JhaAndy Duckworth guardian.co.uk |
Stephen Hawking has not yet disproved God's role in creation The existence of the universe cannot be explained by science aloneAccording to your report, Stephen Hawking claims that God is redundant in explaining the origins of the universe, stating that "the big bang, rather than occurring following the intervention of a divine being, was inevitable due to the law of gravity" (Stephen Hawking says universe not created by God, 2 September). The article publishes an extract from Hawking's new book: "Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist ... It is not necessary to invoke God to light the blue touch paper and set the universe alight." It seems Hawking believes that a law of nature (ie the law of gravity), rather than an immaterial deity, explains the existence of the natural order.But what is a law of nature? Some philosophers hold that the laws of nature are grounded in the causal capacities of physical objects: the capacity of water to boil at 100C, and the capacity of salt to dissolve in water (to take two very simple examples). Other philosophers claim that laws of nature are simply brute regularities in the natural world, which have no ultimate explanation. On either conception, it is difficult to see how laws could explain the natural order, as they seem to depend for their own existence upon that natural order.Hawking has never told us what he thinks a law of nature is, and until he does so it is impossible to assess his claim that laws of nature can explain the existence of the natural order in a way that renders traditional arguments for the existence of God unsound.I don't imagine that Hawking is in a hurry to answer this philosophical challenge. The opening page of his book proclaims that "philosophy is dead", due to the fact that philosophers have failed to keep up with mathematical developments in physics. This doesn't stop him, and his co-writer Leonard Mlodinow, indulging in some very crude philosophical discussions of free will and metaphysical realism in later chapters. Hawking is right to say that most philosophers don't understand cutting-edge physics. But it cuts both ways: most physicists don't understand cutting-edge philosophy.The report also claims, as has been much reported in the media, that "Hawking had previously appeared to accept the role of God in the creation of the universe". However, it is not clear that the quotation from his 1988 bestseller, A Brief History of Time, which is produced as evidence of this alleged theological U-turn, was intended by Hawking in anything other than a metaphorical sense. "If we discover a complete theory, it would be the ultimate triumph of human reason – for then we should know the mind of God." Reports of Hawking's dramatic conversion to atheism are somewhat exaggerated.The skills that make one good at physics are not necessarily the skills that make one good at philosophy. What is required in philosophy is a certain capacity for thinking about everyday concepts in abstraction from their everyday context, an ability distinct from the mathematical skill essential for being a good physicist. Hawking is a great physicist. But he has so far shown no signs of being a good philosopher. At any rate, he has certainly not provided us with a good response to the cosmological argument for the existence of God, the argument that begins from the demand for an ultimate cause or explanation of the natural order.Stephen HawkingPhilosophyPhilip Goffguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Today's Mystery Bird For You To Identify This migratory bird has a large range throughout North America, Mexico, Europe and it even occupies a number of islands. It has a correspondingly large number of subspecies that vary on a regional basis. Can you tell me which one this is?Mystery Bird photographed in Fall City, Washington, USA. [I will identify this bird for you in 48 hours]Image: Jamie Samans, 10 September 2010 [with binoculars].Nikon D50 w/ an 80-400mm f/4.5-5.6D ED VR lens.This migratory bird has a large range throughout North America, Mexico, Europe and it even occupies a number of islands. It has a correspondingly large number of subspecies that vary on a regional basis. Can you tell me which one this is? Daily Mystery Bird Rules: 1. Please name at least one field mark that supports your identification, keeping in mind that more than one field mark is often necessary to distinguish between species. IDs without any supporting information are not valid and may be deleted by the moderators. 2. Expert and intermediate level birders: do NOT try to be the first to blurt out the mystery bird's ID. Instead, please provide helpful hints, such as descriptions, literary references, puns, personal anecdotes, and other forms of discussion and assistance for beginning birders and for those following on their iPhones without naming the species. Expert and intermediate birders are free to name the bird species 24 or more hours after it was first published.3. Each mystery bird is usually accompanied by a question or two. These questions can be useful for identifying the pictured species, but may instead be used to illustrate an interesting aspect of avian biology, behaviour or evolution, or may be intended to generate conversation on other topics, such as conservation. 4. Each bird species will be demystified 48 hours after publication. If you have bird images, video or mp3 files that you'd like to share with a large and appreciate audience, feel free to email them to me for consideration.GrrlScientistguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Ground coffee helps robot get a grip A floppy robotic hand that stiffens when air is sucked out, much like a vacuum-packed brick of coffee, may form the basis of a new type of robotic gripping mechanism, US researchers say. abc.net.au |