【每日阅读训练第四期——速度越障15系列】【15-19】科技

zxppx

标题我用白色标记的，鼠标拉一下就显示出来了。Check the title later. 第三和第四篇文章是一起的，越障部分的照片借用其他文章的，呵呵~
[Time1]

Caffeine Improves Memory in Bees
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After a long day buzzing between flowers, even the most industrious worker bee could use a little help remembering which ones she wants to return to the next day. Some plants have a trick to ensure they end up at the top of the list: caffeinated nectar. A team of researchers bombarded honey bees with floral smells paired with sugary rewards, some of which contained the same levels of caffeine found in the nectar of coffee and citrusflowers (pictured).Three times as many bees remembered the odors associated with caffeine after 24 hours, when compared with the scents associated with sugar alone, the team reports online today inScience. When the researchers applied the stimulant directly to honey bee brains, it had a positive effect on the neurons associated with the formation of long term memories. Now, they want to see if bees go out of their way to feed on caffeinated nectar, perhaps even ignoring predators to do so—behavior that, if observed, could shed light on the neurological processes behind addiction.

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[Time 2]

Mars' Hidden Valleys Deeper Than Thought
[attachimg=347,292]115341[/attachimg]

One of the largest of the recently carved channel systems on Mars, once sculpted by massive floods but now smothered under ancient lavas, is more than twice as deep as previously thought. Using radar data gathered by the Mars Reconnaissance Orbiter, researchers were able to see several dozens of meters below ground level in an area (dotted box, above) including the presumed source of Marte Vallis, a chaotic system of channels (depicted in white) created less than 500 million years ago—a geologically recent era in the Red Planet's history. Previous studies, which considered only the exposed portions of Marte Vallis, suggested that the deepest valleys hidden by lavas that erupted about 10 million years ago were only around 40 meters deep. The new findings reveal that the deepest channels in the 1000-kilometer-long, 100-km-wide system are more than twice that depth, the researchers report online today in Science. Radar data also reveal that the upstream portions of the channels lie near a lengthy system of fissures called Cerberus Fossae, the presumed source of the massive outflow of ground water thought to have carved Marte Vallis. Scientists aren't clear about the total volume of water that flowed from the fissures or the duration of those ancient floods, but the team notes that the depth of the channels in Marte Vallis rivals those sculpted by Earth's largest known megaflood—the so-called Missoula floods that carved the Channeled Scablands of Washington state near the end of the last ice age.'

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[Time3]

Want to Save Lions? Fence Them In
[attachimg=458,356]115342[/attachimg]

A new study of lions in African reserves suggests that most populations should be protected with fences, a strategy that can be expensive in the short-term and is at odds with some conservationists' vision of wildlife. The study also finds that half of unfenced populations of lions are likely to dwindle in the next few decades.

"This paper will cause a stir as it really is the first to scientifically illustrate the value of fencing for the conservation of a large predator," predicts Matt Hayward, a wildlife ecologist with the Australian Wildlife Conservancy in New South Wales, who was not involved in the study.

Lion conservation is difficult and expensive. Three-quarters of their African habitat has been taken over by humans, and over the previous century, their numbers have fallen by perhaps 50%, to an estimated 30,000 to 35,000. Some small populations are already suffering from inbreeding. Compounding the challenge is the fact lions aren't easy to live with. They attack villagers and kill their livestock. These problems can be minimized if lion habitat is isolated with an electrified chain link fence. But fences can cost up to $3000 per kilometer to install. If a smaller population is enclosed, managers have to maintain genetic diversity by introducing new animals every few years. Fences are also impractical if lions pursue migratory prey like wildebeest.

Ecologist Craig Packer of the University of Minnesota, Twin Cities, has seen a lot of the problems caused by lions in Tanzania when they attack cows. "It's a flash point for conflict," he says. People retaliate by killing the lion.

Intrigued by the success of fencing at minimizing conflict with lions in South Africa, Packer decided to take a broad look at the role of fencing in lion conservation. He asked 58 conservation managers in 11 African countries for information about their reserves. Some had records on lion numbers going back 46 years, and a dozen years was the average. Using an ecological model developed by co-authors from the University of Oxford in the United Kingdom, Packer and colleagues compared these figures to the number of lions those habitats ought to be able to support.

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[Time4]

The analysis, published online on 5 March inEcology Letters, showed thatfenced reserves tend to have a higher density of lions and faster population growth than reserves that are open to neighboring land. Lions are doing relatively well in a few unfenced parks, such as Nairobi National Park in Kenya, but these places must spend much more money. Antipoaching patrols and other management costs in unfenced parks can run more than $2000 per square kilometer annually while fostering only half the number of possible lions. In contrast, a fenced reserve can attain 80% of its maximum population density at a quarter of the cost. The difference could be critical for the future of lions; the study found that almost half of unfenced lion populations may sink to less than 10% of their potential size over the next 2 to 4 decades.

"Too many conservationists are romantics at heart," Packer writes toScienceNOW in an e-mail. "But the days of limitless vistas of unspoiled African savanna are gone forever. More parks must be fenced."

Co-author Luke Hunter of Panthera, a conservation organization based in New York City, has some reservations. Rather than fences, he would prefer to see the establishment of buffer zones to separate humans and lions, as well as more of the kinds ofconflict mitigation initiativesthat Panthera has helped establish to reduce the killing of lions. Packer says that this particular approach has done well in Kenya, but it is only feasible when lions are relatively scarce. And there's just not enough money to protect core reserves and buffer zones for all lions, he adds.

"This paper illustrates that successful conservation is not cheap, and given the increasing human pressures, it is not going to get any cheaper" says Graham Kerley, who directs the Centre for African Conservation Ecology at Nelson Mandela Metropolitan University in Port Elizabeth, South Africa. Packer says he hopes to convince development agencies, such as the World Bank, to consider lion fences as infrastructure that can generate revenue from reserves. "eople have got to think big," he says.

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[Time5]

Tropical forests unexpectedly resilient to climate change

Models predict that forests such as the Amazon will keep carbon locked up until 2100.
[attachimg=501,297]115343[/attachimg]

Tropical forests are unlikely to die off as a result of the predicted rise in atmospheric greenhouse gases this century, a new study finds. The analysis refutes previous work that predicted the catastrophic loss of the Amazon rainforest as one of the more startling potential outcomes of climate change.

In the most extensive study of its kind, an international team of scientists simulated the effect of business-as-usual emissions on the amounts of carbon locked up in tropical forests across Amazonia, Central America, Asia and Africa through to 2100. They compared the results from 22 different global climate models teamed with various models of land-surface processes. In all but one simulation, rainforests across the three regions retained their carbon stocks even as atmospheric carbon dioxide concentration increased throughout the century.

Robust rainforest
The study provides “robust evidence for the resilience of tropical rainforests”, says lead author Chris Huntingford, a climate modeller at the UK’s Centre for Ecology and Hydrology in Wallingford. But uncertainties remain, he adds.

For one, it remains difficult to predict how climate will change regionally. Moreover, each global climate model represents climate somewhat differently.

The single simulation that predicted biomass loss for the Amazonian and Central American rainforests in the current study used a model called HadCM3, developed by the UK Met Office's Hadley Centre in Exeter. That same model produced the earlier prediction that climate change would lead to massive forest die-off in the Amazon.

Climate scientist Peter Cox at the University of Exeter, UK, was one of the authors on the earlier study and is also involved in the new one. He explains that, unlike other climate models, HadCM3 predicts extreme drying over the Amazon basin in the future, which changes the outcome for the forests there. But in the light of new data and of improved modelling, the drying now seems a lot less probable. Scientists are more confident in the predictions from current studies, he says, as they are based on many more, and much more sophisticated, models.

“This has been a big issue in science for many years,” says forest ecologist Daniel Nepstad, who directs the Amazon Environmental Research Institute in San Francisco, “and the emerging view is that there is less sensitivity in tropical forests for climate-driven dieback”.

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[越障]

Inequality quantified: Mind the gender gap

Despite improvements, female scientists continue to face discrimination, unequal pay and funding disparities.
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As an aspiring engineer in the early 1970s, Lynne Kiorpes was easy to spot in her undergraduate classes. Among a sea of men, she and a handful of other women made easy targets for a particular professor at Northeastern University in Boston, Massachusetts. On the first day of class, “he looked around and said 'I see women in the classroom. I don't believe women have any business in engineering, and I'm going to personally see to it that you all fail'.”He wasn't bluffing. All but one of the women in the class ultimately left engineering; Kiorpes went on to major in psychology.

Such blatant sexism is almost unthinkable today, says Kiorpes, now a neuroscientist at New York University. But Kiorpes, who runs several mentoring programmes for female students and postdoctoral fellows, says that subtle bias persists at most universities. And it drives some women out of science careers.

By almost any metric, women have made great gains in closing the scientific gender gap, but female scientists around the world continue to face major challenges. According to the US National Science Foundation, women earn about half the doctorates in science and engineering in the United States but comprise only 21% of full science professors and 5% of full engineering professors. And on average, they earn just 82% of what male scientists make in the United States — even less in Europe.

Scientific leaders say that they continue to struggle with ways to level the playing field and entice more women to enter and stay in science. “We are not drawing from our entire intellectual capital,” says Hannah Valantine, dean of leadership and diversity at the Stanford School of Medicine in California. “We've got to put on the accelerator to evoke social change.”

One of the most persistent problems is that a disproportionate fraction of qualified women drop out of science careers in the very early stages. A 2006 survey of chemistry doctoral students by the Royal Society of Chemistry in London, for example, found that more than 70% of first-year female students said that they planned a career in research; by their third year, only 37% had that goal, compared with 59% of males.

Many experts say that a big factor driving this trend is the lack of role models in the upper divisions of academia, which have been slow to change. The Royal Society of Chemistry has found, for instance, that female chemistry students are more likely than males to express low self-confidence and to report dissatisfaction with mentorship. Female students “conclude consciously and unconsciously that these careers are not for them because they don't see people like them”, suggests Valantine. “That effect is very, very powerful — this sense of not belonging.”

The attrition continues at later stages. In biology, for example, women comprised 36% of assistant professors and only 27% of tenure candidates in a 2010 study by the US National Research Council. “We're not talking about a lack of talent here. Part of the story is that women leave earlier. In a sense, they give up on an academic career,” says Curt Rice, vice-president of research and development at the University of Tromsø in Norway, who has studied gender equality in US and European universities.

Family values
Many of the UK chemistry students viewed research as an all-consuming endeavour that was incompatible with raising a family. Meeting the demanding schedule of academic research can seem daunting for both mothers and fathers. But family choices seem to weigh more heavily on the career goals of women.

Law professor Mary Ann Mason at the University of California, Berkeley, and her colleagues have found⁴that male and female postdocs without children are equally likely to decide against research careers, each leaving at a rate of about 20%. But female postdocs who become parents or plan to have children abandon research careers up to twice as often as men in similar circumstances.

“The plan to have children in the future, or already having them, is responsible for an enormous drop-off in the women who apply for tenure-track jobs,” says Wendy Williams, a psychologist at Cornell University in Ithaca, New York. Furthermore, women who do become faculty members in astronomy, physics and biology tend to have fewer children than their male colleagues — 1.2 versus 1.5, on average — and also have fewer children than they desire.

In response to these concerns, many universities have taken steps to establish family-friendly policies such as providing child-care assistance and extending tenure clocks for new parents. Shirley Tilghman, president of Princeton University in New Jersey, believes that such initiatives provide crucial support for women, but that other solutions are still needed. “I don't think there's a single obstacle,” she says. “I think there's a whole series of phenomena that add up.”

Pay problems
The inequalities also extend to salaries. In the European Union, female scientists earned on average between 25% and 40% less than male scientists in the public sector in 2006. Although the average pay gap is smaller in the United States, the disparity is particularly large in physics and astronomy, where women earn 40% less than men.

For young academic scientists, however, those differences may be fading. The National Research Council found an 8% pay gap at the level of full science and engineering professors but no significant differences among junior faculty members. Some experts argue, however, that the salary gap may reflect other continued trends, such as the fact that a disproportionate share of women move into non-tenure positions or faculty jobs at lower-status universities.

Tilghman says that Princeton and many other universities have grown increasingly conscious of the need to track and rectify gender gaps in salary and other institutional support. “Absolutely, it needs eternal vigilance,” she says. “But we're in a much better place.”

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铁板神猴

沙发，拿下！

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58''
1'33''
2'03''
1'43''
1'59''


5'10''

today17蒽

我是不是第一个读的啊~~~好荣幸！！！

枣糕兔

TUT 先占座


————————————————————————作业的分割线——————————————————————————

Speed
59''
01'31
02'05
02'21
02'37

Obstacle
06'41

Main idea: Scientific study/Academic career become harder for the female
Attitude: Neutral
Structure:
>>>henomenon: Sexism is a common and severe problem in academic areas, such as engineering and neuroscience.
>>>ossible reasons:
       1. lacking sense of belonging Fewer and fewer students show an eager to step into an academic career, according to recent survey. And the male usually outnumber the female in scientific institutions.
       2. family value Female scientist usually have fewer children both than male scientists and than their expectations. Plus many woman hold family value more important than career and achievements.
       3. pay problem It's a concrete fact that female scientists are paid less than their male colleagues.

today17蒽

173words 1‘47’2
247words 2‘23’2
358words 3‘45’8
346words 4‘19’9
376words 3‘43’9
987words10‘08’6
这个成绩怎么样啊？斑竹我还有没有希望

cheungby

赞效率，辛苦了

15-19
Time1——56''
Time2——1'43''
Time3——1'51''
Time4——2'2''
Time5——2'55''
Obstacle:5'53'' ——main idea:The article introduced the gender unequality in the fields of science and engineering in the US. and Europe. The author also analyzes the possible reasons why the femalescientists are much more less the male ones, like the family issues, pay problerms.

julielie

Mar. 12th
1. 49"
How can working bees remember which flower to work on the day after? The answer lies on a newly found chemical called XXX. This chemical is like some caffein, which can stimulate bee's neuro system and make bee remember this scent. Scientists further did some experiments to prove this theory.

2. 1'12"
Scientists recently found a trench, which more than doubles the length and width of people used to see, on Mars. Also, there is probably underground water beneath it.

3. 1'44"
There is a debate over whether lions should be fenced in Africa. Proponents state the problem lions caused, such as attacking cows and stepping field. 反方 argue that fencing is very expensive, and unrealistic especially when lions chase some migrating preys, such as deers.

4. 1'59''
Fencing the lions will do them good in the long term.
Some people raised a middle-field solution-make buffering areas.
Whether way taken, we are still short of money. Hopefully, some agencies, such as World Bank, will financialize this plan.

5. 1'53''
Traditionally, people think greenhouse gas do very bad on tropical rainforests, such as Amazon rainforest. But recently, scienticists found that rainforests are less sensitive than people thought previously. The model we used before resulted in this anticipation flaw.

Obtacle:
4'20''
In an engineering class in the 1970s, when the professor said, "Oh, I see some women in this class， who will drop off in the future", his words came true. All the women students transfer to other majors, such as K going to psycology.

This gender bias has improved till now, but by not much. Today, there is still disparity between men and women in the field of science.

Women do not have the self-belonging feeling as men do. Women left this science career much earlier. There could be several reasons explaining this phenomenon as follows.
First, family value.
Second, pay issue.

448406078

楼主……

下次那种小虫虫的图片……

可不可以不要放上来……

…………………………

cleotina

1'04
the coffine nectar can improve the effect of the Bee's memory
1'30
the mar's vally is deeper than thought, and it may created by water stream, like some vallies in the earth caved in the last ice age.
2'40
in order to protect the lions, whether it is pragmatic to set fence
2'40
go to gather fund to reserve lions
3'40
Amazon survive, even in an environment with more and more Greenhouse gases.
6'48
there is still a sexual gap in the science and engeneer area. and two reasons might illustrate this phenomenon:1 family responsibility  2, the salary unequility in these areas.

448406078

1-173-53''
Bees can spread smells to help remember flowers. Those smell contain sugar or caffeine...

2-247-1'23''
Data from Orbiter help scentists find new channel on Mars. The new one is deeper.

3-358- 1'25''
Fences will be install to perserve lions. Lions is not easy to survice and sometimes attack humams and cows. wishing a better live environment by installing fences.

4-346-1'52''
Though not cheap, fencing will help preserve lions. People are thinking about get revenue from fencing.

5-375-1'38''
The greenhouse atmosphere may not cause forests die off. The outcome of climate changing are now measure by model and is difficult to prediate.

967-4'08''
Why women drop out from science?
Real example happen in sceince class. Sutle differences exist in university.
Women abandon in early years. Maybe lack uper model.
Fimly problems:
women plan to have chiledren. Some university are establishing family-firendly
Paying gap:
difference between male and female. Now better but still exist.