TOP 100 SCIENCE SITES
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| Thanks to high-tech, storm track easier to predict By SETH BORENSTEIN 2010-09-02T01:12:19ZWASHINGTON (AP) -- Sophisticated computer models that replaced instinct with cold, hard math have helped forecasters predict where a storm like Hurricane Earl is going about twice as accurately as 20 years ago.... hosted.ap.org |
Boeing enters the space tourism race Engineering firm to offer seats on craft being developed for Nasa to allow passengers to orbit the EarthThe US aircraft company Boeing is to offer passengers the chance to fly into space on a vehicle it is developing for travel in low-Earth orbit.It said yesterday it had reached an agreement with the Virginia-based Space Adventures company to sell passenger seats on commercial flights aboard Boeing's CST-100 space vehicle, being developed for Nasa.The spacecraft could carry seven people and fly in low-Earth orbit as soon as 2015, Boeing said.The company said that potential customers could include private individuals, companies, non-governmental organisations and US federal agencies.Space Adventures, which specialises in selling commercial tickets for private space travel, said it had arranged for seven participants to fly on eight missions to the International Space Station.The companies said that pricing for the planned space flights had not been set but were expected to be competitive.Guy Laliberte, founder the Cirque du Soleil, paid more than $35m (£22m) to travel into space last year on a Russian spaceship from Kazakhstan.Virgin's Richard Branson has already announced plans to offer commercial trips into space for tourists costing around $200,000.The US space shuttle programme, which carries astronauts and supplies to the ISS, is being shut down next year. Barack Obama's administration has launched an initiative to replace Nasa-owned and operated launch services with commercial space taxis.Until a replacement vehicle is ready, the US will be solely dependent on Russia to fly crews to the ISS, a $100bn-project involving 16 nations, which has been under construction 220 miles above Earth since 1998.Russia currently charges Nasa about $51m per seat for a ride on its Soyuz spacecraft. The price goes up to $56m in 2013.NasaSpaceSpace technologyBoeingUnited Statesguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Quarks, gluons and jets | Jon Butterworth The LHC paper I've been working on for the past few months is finally out. It shows quarks and gluons doing what they should do, and I love itIn July we (ATLAS) released a preliminary version of our first jet cross section measurement, and showed it at the International Conference on High Energy Physics (ICHEP) in Paris. Today we submitted the final version of this measurement to the European Physical Journal and to the archive."Cross section" in this context is basically a probability. If you fire two footballs at each other, they have a bigger cross-sectional area than two snooker balls, so they are more likely to hit each other. A "jet cross section" is a measure of how likely we are to see jets when we fire two protons at each other.Jets are what quarks and gluons do when they try to escape. The proton is made up of quarks stuck together by gluons. Most of the fundamental forces get weaker with distance - the Earth's gravitational pull gets weaker the further out into space you go, for example. But the strong nuclear force is the other way round.The force between two quarks actually gets stronger as you pull them apart, more like an elastic band. When two quarks in LHC protons bounce off each other they head away really quickly, feeling almost no force at first (physics buzzwords: asymptotic freedom. See this Nobel Prize citation). But at some point that has to end, because as they get further and further from the protons they were knocked out of, the force pulling them back gets stronger and stronger.You can think of the quarks as being the ends of the elastic band. They fly away from each other until at some point the band snaps and two new ends (new quarks) are produced. Eventually, we see a spray of hadrons (particles, like the proton, which contain quarks and generate amusing typos). Because the initial quarks get kicked so hard, this spray is collimated into a jet, and despite all the splitting and production of new quarks, the direction of the jet reflects pretty well the initial direction of the quark.ResultSo, what you see in the plot below reflects the distribution of quarks and gluons scattered in collisions at the LHC.When we collide protons, we really care most about the collisions between the proton's constituents - quarks or gluons. Unfortunately the quarks and gluons only carry a fraction of the energy of the proton, and we have no way of choosing how much. If the fraction was a half, for example, then we would have jets with 1750 gigaelectronvolts (GeV) of energy (half of 3.5 TeV). But most of the quarks and gluons carry much smaller fractions.To have a real measurement of this, and show that the theory prediction (quantum chromodynamics, labelled QCD on the plot) agrees with the data, is a real achievement. It directly involved dozens of people, and less directly hundreds. One key component is the energy calibration which I described here.This result, like the minimum bias results, is part of finding our feet in the new energy regime of the LHC - but these collisions are much closer to where we want to be. And we already have about 300 times more data to play with than is shown here, with more flooding in. We are already using these data to look for new forces and particles (see here and here).PSWhen we put the preliminary results out, I wrote an earlier version of this article. Unlike the data, it changed quite a bit in between! In a good way.Jon Butterworthguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
UK scientists develop urine test to detect prostate cancer risk Breakthrough could mean more accurate predictions of disease, which affects around 35,000 men in Britain each yearBritish scientists may have paved the way for a simple and reliable test to discover which men are at high risk of developing prostate cancer, it has emerged.The breakthrough could mean more accurate predictions of the disease which affects around 35,000 men in Britain each year, leading to 10,000 deaths.A urine test to detect levels of the protein MSMB could replace current blood testing for the disease after research showed the protein is present at reduced levels in men diagnosed with the disease.Levels also appear to be affected by tumour aggressiveness.Currently doctors rely on blood tests for prostate specific antigen (PSA) to assess the risk and progress of the disease.MSMB level is affected by a genetic change linked to prostate cancer.The research, published in the online journal Public Library of Science ONE, shows that the urine test has proven to be twice as precise as the current method.Study leader Dr Hayley Whitaker, from Cancer Research UK charity's Cambridge Research Institute, said: "We looked in tissue and urine from over 350 men with and without prostate cancer to find out how much MSMB they had."We then looked to see who had the genetic change. It was really exciting to find out that the genetic change and the amount of protein were linked."The protein is easy to detect because it is found in urine and would potentially be a very simple test to carry out on men to identify those most at risk of developing the disease."Dr Kate Holmes, research manager at The Prostate Cancer Charity, said: "These preliminary results show that MSMB, a protein produced by the prostate gland, is found at significantly lower levels in the urine of men diagnosed with prostate cancer than those without the disease. The study also found that men with an aggressive tumour were also likely to have lower levels of the protein in their urine."The study suggests that measuring levels of this protein could potentially be a powerful way to predict how likely a man is to develop prostate cancer."However, further research on a much larger scale is needed to determine how effective the detection of MSMB in the urine is for predicting the risk of, and potentially even diagnosing, prostate cancer."The research could led to urine testing kits, less expensive than the blood testing, at GP surgeries, with results available within hours. A trial on 1,200 men is currently underway and is expected the be completed by Christmas.Further larger-scale trials will also have to be carried out. Men found to have low levels of MSMB could then be closely monitored with the aim of detecting the disease, should it develop, as early as possible.Prostate cancerCancerMedical researchCancerHealthCaroline Daviesguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
US envoy: Climate deal still possible in Mexico By 2010-10-22T10:57:45ZBEIJING (AP) -- A global agreement to curb carbon emissions is possible at an upcoming U.N. climate conference but hinges on the efforts and political will of countries, the U.S. climate envoy Todd Stern said Friday in Beijing.... hosted.ap.org |