Lisa Raffensperger, Author at New 女生小视频 Science news and science articles from New 女生小视频 Tue, 30 Aug 2016 14:19:04 +0000 en-US hourly 1 https://wordpress.org/?v=7.0.2 242057827 Why words are as painful as sticks and stones /article/1977313-why-words-are-as-painful-as-sticks-and-stones/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Wed, 28 Nov 2012 18:00:00 +0000 http://mg21628932.100 1977313 Study physics if you want a ticket to ride /article/1975205-study-physics-if-you-want-a-ticket-to-ride/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Wed, 19 Sep 2012 17:00:00 +0000 http://mg21528832.700 Postcard perfect: the view from the Keck Observatories in Hawaii is one of the job's perks
Postcard perfect: the view from the Keck Observatories in Hawaii is one of the job鈥檚 perks
(Image: Roger Ressmeyer/Corbis)

CALL it the Higgs boson effect, the Big Bang Theory effect or even the Brian Cox effect, if you must. There鈥檚 no getting away from it 鈥 after years in the doldrums, physics is cool.

Just a few years ago it was almost an extinct subject at A-level, but this year university applications to read physics saw a 7 per cent leap despite the fee increase. And if you鈥檝e come out the other side, you can be forgiven for being more than a little smug: not only can you impress at parties by explaining the latest news on the Higgs, but you can take your pick of an enviable range of career options, and are likely to command a higher starting salary than graduates in the other sciences.

鈥淧hysicists are always in demand, across all sectors,鈥 says Stephanie Richardson, head of membership development at the (IOP) in London. 鈥淭heir problem-solving skills, their mathematical skills, their ability to think critically 鈥 these transferable skills are useful in a huge range of areas, irrespective of the topic.鈥

To the ends of the Earth

From mountaintops to desert plains, abandoned mines to the depths of the ocean, physics research is a ticket to some unique destinations. Luca Rizzi works at one of the most advanced telescopes in the world 鈥 and even the daily commute is a source of satisfaction. 鈥淲hen I drive home, it鈥檚 about sunset time, and for 25 minutes all I see is ocean and sunset. It鈥檚 so rewarding, every day.鈥 Rizzi is a support astronomer, assisting academics visiting the on top of the Mauna Kea volcano in Hawaii.

聯When I drive home, it鈥檚 about sunset time and for 25 minutes all I see is ocean and sunset. It鈥檚 so rewarding, every single day聰

Far from Hawaii, Carlos Pobes of the University of Wisconsin-Madison doesn鈥檛 see the sunset for months on end 鈥 he works on the in Antarctica. The detector, the biggest of its kind in the world, uses sensors buried more than a mile beneath the ice of the South Pole to record data on high-energy neutrinos as they pass silently through the Earth.

The driest place on Earth, the Atacama desert in Chile, also draws physicists 鈥 it鈥檚 a superb site for making observations of the sky in the radio spectrum. Postdoc Jeff Wagg is based at the Atacama Large Millimeter/submillimeter Array (ALMA), where he studies galaxies from the first hundred million years after the big bang. Wagg, who is employed by ALMA鈥檚 operator, the , says that for him, travelling the world was a big part of the attraction of a career in astrophysics. He has made the most of his assignments, taking the opportunity to surf in Chile and dive in the Pacific during his time off. 鈥淵ou definitely take it into account when you鈥檙e putting in proposals. I have a collaborator who鈥檚 always coming up with ideas to allow us to return to Hawaii.鈥

A background in astrophysics is the natural precursor to observatory work, and you can gain experience by travelling to observatories alongside professors as part of a relevant PhD project, or by building instrumentation in the lab, says Bob Goodrich, head of the observing support group at the Keck Observatory. IceCube鈥檚 research group recruits physicists directly for their 鈥渨inter-over鈥 positions: you need no prior sub-zero experience, but have to be prepared to stick it out for the whole of the Antarctic鈥檚 seemingly endless winter.

Into space

We might be a little behind the US and Russia, but if the politicians are to be believed, the UK鈥檚 heyday in space is at hand 鈥 and physicists are poised to reap the rewards.

In 2010, the was established, bringing together all the country鈥檚 space interests under one body. But the space sector was in rude health even before that, says Keith Mason, a director of the even more recently launched (ISIC) in Harwell, Oxfordshire. The boom has largely come off the back of new applications spun out from space technology, such as satnav, and the promise of a bigger market as the global space industry increasingly becomes privatised. ISIC has been set up to take advantage of these.

Financial rewards aside, the country鈥檚 involvement in high-profile projects such as the James Webb Space Telescope has given the UK鈥檚 space endeavours extra lustre in recent years. 鈥淭here鈥檚 a real buzz about the space industry,鈥 concurs Geoff Buswell, a project director at ISIC. 鈥淪ome of my senior colleagues say they鈥檝e never seen it like this before.鈥

But the industry is 鈥渄esperately short of people with the right skill set鈥, says Mason, and this is the case across government, industry and academia. Buswell, who has been seconded to ISIC from the IT company , went into industry after his PhD because he 鈥渨anted the buzz and urgency of a commercial environment鈥. Aerospace firms such as Astrium run apprenticeships and graduate entry schemes, as does Logica, which develops software for space applications such as satellites. The UK Space Agency and the also provide opportunities; ESA runs a trainee scheme for master鈥檚 level students and offers postdoc opportunities. Finally, if your dream is to become an astronaut, that鈥檚 possible at ESA as well, although much more difficult 鈥 the last time it accepted recruits to the European Astronaut Corps was in 2009.

To the City

By far the biggest employer of new physics graduates is the financial sector, which took in nearly a fifth of 2011 graduates. Employers love physicists鈥 numeracy and analytical skills, while successful applicants enjoy higher starting salaries than most other professions can offer, and a fast-paced environment.

鈥淎 major misconception is that you have to be an economist to work here,鈥 says Cat Hines, a graduate recruiter at the Bank of England. 鈥淲e鈥檙e not expecting graduates to demonstrate any technical knowledge about economics or finance during the recruitment process; it鈥檚 purely about how they take the information that鈥檚 given to them, pull out what鈥檚 important and present it back to us.鈥 Graduate schemes at banking and investment firms are highly competitive, and it can boost your chances of selection if you can secure an internship during the summer of your penultimate year at university.

鈥淲hen I arrived I had to learn a new language 鈥 the language of economics and finance,鈥 says Jack Garrett-Jones, a regulatory policy analyst at the Bank of England, which he joined right after he graduated. 鈥淏ut once I got that in my head, it was actually the same underlying structures and thought processes I used in my degree鈥.

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Roads less travelled for physics graduates /article/1975210-roads-less-travelled-for-physics-graduates/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Wed, 19 Sep 2012 17:00:00 +0000 http://mg21528832.800 1975210 Blonde hair evolved independently in Pacific islands /article/1970819-blonde-hair-evolved-independently-in-pacific-islands/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Thu, 03 May 2012 18:00:00 +0000 http://dn21779 The blonde TYRP1 mutation in Solomon Islanders isn't found in other people from outside the South Pacific
The blonde TYRP1 mutation in Solomon Islanders isn鈥檛 found in other people from outside the South Pacific
(Image: Danita Delimont/Getty Images)

Science can鈥檛 yet tell us whether they have more fun 鈥 but it has uncovered a new genetic change that makes people blonde. And contrary to long held belief, it seems golden hair hasn鈥檛 simply been introduced across the globe by travelling tow heads, but instead evolved separately in different human populations.

Indigenous people of the Solomon Islands in the South Pacific have some of the darkest skin pigmentation outside of Africa. But unlike most other tropical populations, they also have a high prevalence of blonde hair. Up to 10 per cent of the population is fair haired, the highest proportion outside of Europe. Until now, this odd trait had generally been attributed to the introduction of blonde genes by European explorers and traders in preceding centuries. 鈥淲e originally thought, well that must be a Captain Cook allele,鈥 says at Stanford University.

Yet a closer look revealed that the genetics behind blonde hair in Brussels are distinct from those leading to flaxen locks in the South Pacific.

Bustamante, Sean Myles and colleagues at Stanford discovered this after analysing saliva samples from 43 blondes and 42 dark-haired Solomon Islanders. A genome-wide scan pointed to a single strong difference between the groups at a gene called TYRP1. Further analysis revealed that a single-letter change in the gene accounted for 46 per cent of the population鈥檚 hair colour variation, with the blonde allele being recessive to the dark hair allele. The blonde mutation wasn鈥檛 found in any of the 900 other individuals sampled from outside the South Pacific (, DOI: 10.1126/science.1217849).

TYRP1 is known to be involved in skin and hair pigmentation in several species. In normally black mice, for example, a mutation in the gene produces light brown coats. A rare kind of human albinism is also caused by mutations in TYRP1, which produces reddish skin colour and ginger hair. TYRP1 isn鈥檛, however, one of the genes that produces blonde hair in Europeans. The novel blonde mutation in Solomon Islanders is likely to have cropped up around 10,000 years ago, and it appears to be the same one behind blondness in Fiji and other regions of the South Pacific.

鈥淏efore this, everybody would have thought, blonde hair evolved once in humans,鈥 says Bustamante. 鈥淭his tells us we can鈥檛 really assume that even these common mutations are common across different human populations. Non-European populations are critical to study to find mutations that may be underlying the vast phenotypic variation of humans.鈥

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Cells reprogrammed to mend a broken heart /article/1970596-cells-reprogrammed-to-mend-a-broken-heart/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Fri, 27 Apr 2012 14:50:00 +0000 http://dn21753 Fixing a broken heart has never been easy, but damaged mice hearts can now be repaired by transforming injured cells into healthy beating muscle cells. The approach sidesteps the use of stem cells and could lead to new heart treatments.

After a heart attack, cells called fibroblasts flock to damaged areas where they deposit collagen. Because fibroblasts do not contract like heart muscle cells 鈥 known as cardiomyocytes 鈥 the heart鈥檚 overall pumping ability in this area is weakened, leading to a less efficient heart.

at Duke University in Durham, North Carolina, has now shown that microRNAs 鈥 small molecules that act as 鈥渕aster switches鈥 for a large number of genes 鈥 can transform fibroblasts into muscle cells.

In cultured mouse fibroblasts, a combination of four microRNAs delivered by viruses transformed 4 per cent of the cells into cardiomyocytes. When a drug called Jak Inhibitor I was added to the cocktail, almost 30 per cent of the cells were transformed.

Same difference

The transformed cardiomyocytes showed the same properties as native cardiomyocytes, including an altered anatomy and weak contractions. Dzau found a similar response after injecting the viruses into mice with heart damage. 鈥淭he new cardiomyocytes totally integrated in the heart. You can鈥檛 tell the cells apart,鈥 Dzau says.

The approach may be a better alternative to using stem cells that have also been shown to restore heart function. Embryonic stem cells face ethical challenges, while manipulating adult stem cells is a technically complex process.

Direct reprogramming of fibroblasts to heart muscle in mice was also reported last week by Deepak Srivastava at University of California, San Francisco (). Srivastava鈥檚 group used transcription factors 鈥 proteins that switch genes on and off 鈥 rather than microRNAs to genetically change the cells鈥 identities.

In the future the two approaches could be used together to increase the number of cells converted. 鈥淚 think the microRNA work is intriguing and supports the paradigm that the abundant pool of non-muscle cells in the heart can be converted into new cardiac muscle,鈥 says Srivastava. 鈥淭he microRNAs may improve the efficiency of the conversion together with the previously described factors from our group.鈥

鈥淒irect reprogramming is the most exciting thing in cell therapy. Now there are two ways that you can actually do it in an animal 鈥 and that sets the stage for human therapeutics,鈥 Dzau says.

Journal reference:

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Male bowerbirds grow a garden to attract a mate /article/1970403-male-bowerbirds-grow-a-garden-to-attract-a-mate/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Mon, 23 Apr 2012 16:00:00 +0000 http://dn21736
Cultivating berries? (Image: David Kleinert)
Cultivating berries? (Image: David Kleinert)

What has green fingers but no hands? The bowerbird, if a new study is to be believed. Males appear to cultivate plants around the structures they build to attract a mate.

Male spotted bowerbirds () build structures, or bowers, from twigs before intricately decorating them with objects to attract a female. One of the males鈥 most desirable decorations is the berry of the plant.

of the University of Exeter, UK, and colleagues studied the distribution of S. ellipticum in an area of Queensland, Australia, inhabited by the birds. Although the males didn鈥檛 build their bowers in locations with abundant S. ellipticum, a year after construction there were, on average, 40 of the plants near each. Birds with more plants nearby had more berries within their bowers, which Madden has previously found is the best predictor of a male鈥檚 mating success. Males may discard shrivelled berries outside their bowers.

The bowerbirds are thus shaping the distribution of the plants in the area 鈥 but is it cultivation? Madden acknowledges the results do not imply that the birds intentionally grow the plants. But he points out that some hypotheses favour similarly unintentional origins for human agriculture, suggesting the bowerbirds鈥 activities could just about fall under the definition.

Journal reference: , DOI: 10.1016/j.cub.2012.02.057

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Clues to aspirin’s anti-cancer effects revealed /article/1970346-clues-to-aspirins-anti-cancer-effects-revealed/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Thu, 19 Apr 2012 18:00:00 +0000 http://dn21718 Aspirin activates AMPK, an enzyme involved in metabolism, which plays a role in cancer
Aspirin activates AMPK, an enzyme involved in metabolism, which plays a role in cancer
(Image: Nicholas Eveleigh/Getty)

One of the world鈥檚 oldest medicines may hold the secret to a very contemporary problem: preventing cancer. Exactly why salicylate shows such potential as an anti-cancer treatment remains unclear, but a new study in mice offers clues.

Salicylate, found in willow bark, has been a key ingredient in medicine cabinets for thousands of years 鈥 ancient Egyptian manuscripts describe it as a treatment for inflammation. In a modified form 鈥 aspirin 鈥 it remains a successful anti-inflammatory and analgesic. Recently, though, research has revealed a puzzling side-effect of taking aspirin: the drug seems to lower a person鈥檚 chances of developing some forms of cancer.

Aspirin is rapidly broken down inside the body into salicylate, so to investigate aspirin鈥檚 unexpected side-effects at the University of Dundee, UK, applied salicylate to cultured human cells derived from the kidney. He found that the drug activated AMPK, an enzyme involved in cell growth and metabolism that has been found to play a role in cancer and diabetes.

鈥淭his is an ancient herbal remedy which has probably always been part of the human diet,鈥 says Hardie. 鈥淏ut despite that we鈥檙e still finding out how it works.鈥

Co-author of McMaster University in Hamilton, Ontario, Canada, then tested high doses of salicylate on various types of mice. He found that those engineered to lack AMPK did not experience the same metabolic effects from salicylate as seen in mice with AMPK.

Salicylate, in a form called salsalate, has also shown promise as a treatment for insulin-resistance and type 2 diabetes. Those effects, however, appear not to be governed by AMPK. When insulin-resistant mice lacking AMPK were given salicylate, they showed the same improvement in blood glucose levels as normal mice.

鈥淭hat鈥檚 what makes aspirin so scientifically and clinically interesting,鈥 says at the University of Bristol, UK, who was not involved in the work. 鈥淚t potentially works through a number of different pathways.鈥

The finding potentially separates aspirin鈥檚 pain-relieving effects from its cancer protection, paving the way for new anti-cancer drugs that have fewer side-effects than aspirin. The next step will be to test salicylate directly in mouse models of cancer, and to see whether AMPK remains important in mediating an anti-cancer effect.

Journal reference: , DOI: 10.1126/science.1215327

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Blood test could diagnose teen depression /article/1970143-blood-test-could-diagnose-teen-depression/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Tue, 17 Apr 2012 14:00:00 +0000 http://dn21707 Diagnosing depression may get a little easier, thanks to the first blood test that can identify depression in teenagers.

Depression is hard to diagnose in teens due to healthy hormonal changes. To change that, at Northwestern University in Illinois and colleagues first worked out which genes are involved in the condition by comparing gene expression in rats with depression to that in normal rats.

They then analysed the expression of 52 of these genes in blood samples from 28 teenagers, half of whom had depression. Abnormal levels of expression for 11 of the genes were found to be associated with the condition.

They also identified changes in the levels of expression of 12 other genes that were specific to teenagers that had been diagnosed with depression with anxiety.

Being able to objectively test for depression will reduce its stigma, Redei says: 鈥淥nce you can measure it then everybody believes it鈥檚 real.鈥

Journal reference: Translational Psychiatry, DOI: 10.1038/tp.2012.26

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Dear Diary, from Darwin’s daughter /article/1970096-dear-diary-from-darwins-daughter/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Thu, 12 Apr 2012 12:00:00 +0000 http://dn21694
Darwin saw his daughter as a
Darwin saw his daughter as a 鈥渃o-labourer鈥
(Image: <a href="http://www.darwinproject.ac.uk/hed-diary-1871">Darwin Correspondence Project/Cambridge University Library</a>)
A page from Henrietta's diary
A page from Henrietta鈥檚 diary
(Image: Darwin Correspondence Project/Cambridge University Library)

鈥淗ow long, how long has this twelve hours been 鈥 & will it be the end? I go over every chance every possibility, in so far as I can conceive them 鈥 but come to no conclusions 鈥 not unnaturally considering the insufficiency of my data.鈥

This emotive passage has a curiously scientific bent 鈥 curious until you learn it was written by Charles Darwin鈥檚 daughter, Henrietta. As Darwin鈥檚 eldest daughter to survive to adulthood, Henrietta was a key editor of some of her father鈥檚 most famous works. The contents of the passage indicate that she had more nuanced views on science and religion than previously thought, and that she probably made constructive contributions to Darwin鈥檚 writings.

鈥淭he wonderful thing about the diary is that she was very sophisticated about her thinking on science and religion,鈥 says Alison Pearn of the at the University of Cambridge. 鈥淢y interpretation is that she was moving toward a humanistic division. Like Darwin, she was unable to reconcile aspects of his theories with orthodox Christian religion.鈥

Writings in the small leather diary 鈥 recently donated by the Darwin family 鈥 deal with topics of religion, free will and eternal life. They overturn the prevailing image of Henrietta as a rigid believer who tried to suppress the agnosticism in Darwin鈥檚 writings.

The diary was written over a few months in 1871, when Henrietta was 28 years old. It was the same year that Darwin published The Descent of Man and Selection in Relation to Sex.

Pearn says the diary helps 鈥渞ehabilitate鈥 Henrietta as well as help better understand the editorial role Darwin鈥檚 whole family played in shaping his work. 鈥淗enrietta鈥檚 contribution to Darwin鈥檚 work, in particular on religion, has been seen as purely negative 鈥 鈥榚diting out鈥 rather than editing in any constructive sense,鈥 Pearn says. 鈥淣ow we can see her as her father saw her, as a 鈥榙ear coadjutor & fellow-labourer鈥, and as a lively member of an intellectually stimulating household.鈥

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