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[阅读小分队] 【每日阅读训练第四期——速度越障2系列】【2-02】科技

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发表于 2012-5-23 03:41:39 | 显示全部楼层 |阅读模式
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Alzheimer's Research Strategy Announced
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An international panel of experts released recommendations today for future research on Alzheimer's disease. The recommendations will help guide the research component of the new national plan for Alzheimer's disease announced Tuesday by Health and Human Services Secretary Kathleen Sebelius. The plan sets the ambitious goal of developing effective prevention and treatment strategies for Alzheimer's by 2025.
The new research strategy was developed by experts who met during a 2-day summit at the U.S. National Institutes of Health (NIH) in Bethesda, Maryland, earlier this week. The panel acknowledges a number of challenges facing the field, including the need to develop better experimental models and to initiate clinical trials at earlier stages of the disease. Their recommendations include conducting more interdisciplinary research on the biological mechanisms of Alzheimer's disease and therapeutic targets, enabling more rapid and extensive sharing of data and biological specimens, and fostering more public-private partnerships (along the lines of the Alzheimer's Disease Neuroimaging Initiative, a successful biomarker development effort jointly funded by NIH and the pharmaceutical industry). The panel also calls for more research on nondrug interventions, such as lifestyle changes, that might prevent or slow the disease.
A financial stimulus for Alzheimer's research appears to be in the works: President Barack Obama's proposed 2013 budget includes $80 million in new funding. Congress has yet to weigh in on that plan.
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Japanese Earthquake Yields Clues to Posttraumatic Stress Disorder
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Most traumatized people don’t develop the vivid flashbacks and relentless thoughts of the incident that are hallmarks of posttraumatic stress disorder (PTSD). But researchers know little about how trauma changes the brain—and whether some people's brains are more susceptible to PTSD to begin with. Now, neuroscientists in Japan who are working with survivors of the 2011 earthquake and tsunami have identified one brain region whose size seems to predict susceptibility to PTSD symptoms and another brain region that shrank slightly in people with the highest number of symptoms.
Previous imaging studies have found that in PTSD sufferers, parts of the brain involved in memory, fear, and mood control are smaller compared with the brains of people who come through their trauma more-or-less unscathed. But it has been difficult to tell whether these differences were always there or appeared after the trauma. For cognitive neuroscientist Atsushi Sekiguchi, who was studying the neural underpinnings of stress at Tohoku University in Sendai, the earthquake was a rare opportunity to tease apart cause and effect. “We had a lot of brain imaging data for university students before the earthquake,” he says. The coastal region of Tohoku was one of the hardest hit, with tsunami waves as high as 40 meters sending floods up to 10 kilometers inland. In Sendai, the largest city, waves flooded the streets and the airport, sending cars and even planes swirling through the city while black smoke billowed from the burning Nippon Oil refinery.
To investigate the effects of the disaster on residents, the researchers recruited 42 of their earlier subjects for magnetic resonance imaging scans 3 to 4 months after the quake. The subjects also rated the frequency and intensity of their PTSD symptoms, such as intrusive memories, avoiding people or places associated with the trauma, heightened startle response, and feelings of reexperiencing the event.
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None of the subjects had full-blown PTSD at the time of the test; the highest score on the symptom scale, 39, was just below the cutoff for a PTSD diagnosis. But the MRI scans showed that even 3 months after the trauma, some of the students’ brains were already changing in a way that tallied with PTSD symptoms.
Even before the earthquake, a brain region called the pregenual anterior cingulate cortex was smaller in subjects with higher scores than in subjects with few or no symptoms. Previous research has revealed that this region, which plays a key role in monitoring and controlling emotions, is smaller in PTSD sufferers. According to Sekiguchi, the new finding suggests that the reduced size is a “vulnerability factor” for the disorder. Another area, called the orbitofrontal cortex, seemed to be affected by the trauma itself. Students who showed a decrease in volume in this area, compared with their earlier scans, had higher PTSD scores, the team reports online today in Molecular Psychiatry. Because this region is involved in eliminating fear-related memories, the fact that it proved to be smaller in subjects with more intense symptoms makes sense, Sekiguchi explains.
Psychiatrist Roger Pitman of Harvard Medical School in Boston calls the findings tantalizing. “The study shows how sensitive the brain is even at comparatively low levels of symptoms,” he says. The ability to identify the brain areas affected by the condition—as well as those that set the stage for it—adds to our knowledge but doesn’t have immediate implications for treatment, Pitman believes. He adds that future strategies might include scanning people in advance who are expected to be involved in trauma—soldiers, for instance—to spot those at risk for the disorder. Researchers might also develop neuroprotective drugs for specific brain areas. “But we aren’t there yet,” Pitman says.
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U.S.-China Research Projects Draw Congressman's Ire

The United States government is "insane" to be funding collaborative research with China according to a senior Republican member of the U.S. House of Representatives Committee on Science, Space, and Technology.
Representative Dana Rohrabacher (R-CA), a 12-term lawmaker and frequent critic of China's human rights record, last night took to the floor of the House for nearly 30 minutes to read a list of dozens of federally funded projects "that go directly to supporting development and the economy of China." Many involved grants for research involving physics, climate science, and environmental studies—but a few covered topics that included "judicial education" and green manufacturing.
"Couldn't we have spent this money better in the United States?" Rohrabacher asked.
Among his targets were a $63,000 National Science Foundation grant to Siena College in Loudonville, New York, for neutrino physics at China's Daya Bay nuclear facility, a $300,000 Department of Energy grant for modeling regional climate change in China, and a $100,000 U.S. Department of Agriculture grant for "climate change adaptation." "Now isn't that great?" Rohrabacher said in one of many ironic asides. "We're paying for them to adapt to climate change."
Rohrabacher also alleged that "Chinese cyberspies have stolen all of our trade secrets. All of the money we put in to invest in research and development they steal and utilize." He ended his remarks by "suggesting that what we are doing is insane."
U.S.-China relations are often a flashpoint for controversy. Two years ago, Congress banned the White House and NASA from spending any money on scientific collaborations with China. The Obama Administration resisted on the grounds that it infringed on the president's authority to conduct foreign policy. The issue was resolved after White House science officials agreed to give Congress 30 days' notice of any pending collaborations and to certify that none of the exchanges pose a threat to national security. The Administration has also defended such collaborations by highlighting their potential benefits for the United States, for example, in controlling the spread of avian flu or reducing global greenhouse gas emissions.
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Your Inner Bugs Are What You Eat
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The United States may be the home of multiculturalism, but American guts sport much less diversity than those of rural residents of Malawi and Venezuela. That's the conclusion of a new study, which finds that the protein-rich diet consumed by people in western countries may have a profound effect on the microbes they harbor. American gut populations also seem more adapted to a meat-rich diet.
In the body, microbes outnumber human cells by a factor of 10 to one. Research into these vast bacterial populations—together called microbiomes—is booming. Scientists have discovered that microbial boarders play a crucial role in breaking down certain nutrients in the diet and turning other molecules into a form that is useful to humans. The composition of the microbiome also impacts how susceptible a host is to certain diseases, they suspect.
To test that hypothesis, however, scientists first need to get a handle on what the microbiome of healthy adults looks like. So gastroenterologist Jeffrey Gordon at Washington University in St. Louis and his colleagues collected fecal samples from 532 individuals of all ages, more than half of them living across the United States, the rest Amerindians living in two villages in Venezuela and members of rural communities in Malawi. The researchers froze the samples, pulverized them, and extracted DNA. By picking out and sequencing 16S rDNA, a piece of DNA common to all microbes and used to classify them, the scientists could identify the species present in the gut microbial community.
They found that the microbiome in all three populations matured in a similar way: Infants started out with fewer microbe species, but at age three, the diversity of their microbiome had reached that of adults. "Like other organs, it takes the microbiome time to develop," says Dusko Ehrlich, a microbial geneticist at the National Institute for Agricultural Research in Paris who is coordinating a European project to establish associations between the genes of human intestinal microbes and disease.
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The adult microbiomes of Amerindians and Malawians were surprisingly similar, the team reports online today in Nature, but those in the United States differed significantly. For one thing, they were much less diverse, harboring roughly 25% fewer species than Venezuelan microbiomes. Ehrlich calls that "a very strong and unexpected finding. … There seems to be a loss in diversity in Western microbiomes," he says.
By fully sequencing 110 of the samples, the researchers also found differences in which genes were represented in the microbiomes of adults in the three countries. Alpha-amylase, an enzyme involved in the breakdown of starch, was more common in the microbes found in samples from Malawi and Venezuela; U.S. microbiomes contained more genes involved in breaking down amino acids and simple sugars. The researchers speculate that the disparity reflects differences between the U.S. diet, rich in proteins and sugars, and those in Malawi and Venezuela, which are dominated by corn and cassava.
An analysis of the gut microbiome of 33 mammals done by Gordon's group and published in Science in 2011 also showed that microbiomes correlate with diet. Overall, Amerindian microbiomes most closely resemble those of herbivorous mammals, he says, while U.S. microbiomes look more like those found in carnivores. "At least one facet of our genetic landscape is being impacted by our Western diet," Gordon concludes. "What that means for the risk of disease will have to be ascertained in future studies."
Microbiologist Jonathan Eisen of the University of California, Davis, compares the work to the exploration of a new continent: "Everything is new, everything is discovery." But he thinks it's too early to single out diet as the causative factor behind the variation. "There are a million differences between these samples, now they have microbial differences to go with them, but we have no idea which change goes with which," he says.
David Relman, microbiologist at Stanford University School of Medicine in Palo Alto, California, also cautions against drawing broad conclusions. "Although the current study represents a heroic effort," he says, "we still have a long way to go before we have a truly global picture of variation in the human microbiome."
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Life at the Top Can Be Good for Your Health
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Many studies in humans and animals suggest that chronic stress is bad for one’s health, in part because it suppresses the immune system. But nearly 30 years of data on wild baboons shows that top-ranking males, despite showing signs of increased stress, recover more quickly than low-ranking baboons from wounds and illness. The results may help explain why some people escape from the negative effects of stress while others do not.
Most studies in humans have shown a clear correlation between higher socioeconomic status and lower risk of death or illness from stress-related diseases such as heart attacks and diabetes. Some of the most famous of these are the so-called Whitehall studies of the British Civil Service, which showed that death and illness rates decreased in a step-wise fashion the higher an employee was on the service’s 6-grade pay and responsibility scale. These and other studies also have found that being at the bottom of the totem pole leads to greater stress as a result of increased work loads and time pressures, as well as more job insecurity.
But studies of animals, especially other primates, have shown that the relationship between stress and status largely depends on the social organization of the species in question. For example, in species such as baboons that have rigid social rankings and hierarchies, with so-called alpha males dominating other males and females over extended periods of time, it can apparently be more stressful at the top. In a study reported last year in Science, a team that included ecologist Jeanne Altmann of Princeton University revealed that baboon alpha males had the highest levels of glucocorticoid hormones, such as cortisol, as well as testosterone in their feces, indicators that they were under greater stress than lower-ranking individuals.
To try to tease out the relationship between social rank, stress, and health, Altmann teamed up with Elizabeth Archie, a behavioral ecologist at the University of Notre Dame in South Bend, Indiana, and Susan Alberts, a behavioral ecologist at Duke University in Durham, North Carolina, to analyze data collected from 1982 through 2009 in the Amboseli region of Kenya, home to a large population of wild baboons.
Working with three Kenyan field assistants who observed the baboons 6 days a week, 52 weeks each year, the team noted 633 cases of either illness or injury in 166 adult male baboons over the 27-year course of the study. Illnesses included digestive and respiratory problems, while injuries included cuts, slashes, and puncture wounds. The team found that the highest incidences of illness occurred in the oldest and lowest-ranking males, rather than the highest-ranking alpha males, as might be expected if the alpha males’ higher stress levels were suppressing their immune systems. And the highest rates of injury were found in middle-aged, mid-ranking males, the authors report online today in the Proceedings of the National Academy of Sciences.
To further investigate the effect of stress levels on the baboons’ immune systems, the team analyzed healing rates in 144 of the baboons. The researchers found that low-ranking males typically required about 31 days to recover, whereas high-ranking males required about only 25 days.
Since age and rank are correlated—older baboons are less likely to be high-ranking—the team corrected for the effect of age, but found that rank was still the most important factor in predicting wound-healing time. The researchers also identified a correlation between speed of wound-healing and the size of the social group the baboon belonged to: Males from larger groups recovered more quickly than those in smaller groups.
These results are “somewhat surprising,” the team writes in its report, because a number of studies with laboratory animals and captive primates have shown a clear relationship between stress levels—as measured especially by fecal glucocorticoid concentrations—and immune suppression.
The researchers suggest that primates such as baboons and humans have benefited from an “evolutionary flexibility” in how they respond to stress and that immune suppression is not always the result. Thus the higher levels of stress hormones in alpha males, the team contends, are probably due to the stress of expending the energy necessary to stay competitive and on top of the hierarchy, whereas low-ranking males are stressed out by social factors such as being the targets of aggression by alpha males.
Nevertheless, the researchers argue, alpha males and lower-ranking males seem to benefit from the social support they receive by being in larger groups.
“Our results suggest that even though alpha males experience high stress, they seem to escape from the negative consequences,” Archie says. “In humans, we probably see similar patterns. Although people of high socioeconomic status experience stressful events, they probably also have better access to resources and coping mechanisms.” In contrast, Archie says, “low-ranking baboons and people of low socioeconomic status experience long-term stressors with little chance to escape.” Nevertheless, Archie and her co-workers say, more research will be necessary to determine the precise relationship between health and rank—that is, whether healthy animals achieve higher ranks or higher-ranking animals achieve better health.
Michaela Hau, an evolutionary physiologist at the Max Planck Institute for Ornithology in Germany, says that the new study is “immensely valuable” because it was carried out with a large number of baboons who lived in the wild rather than a captive population, which might be suffering from different kinds of stresses due to captivity, social isolation, or variable food quality. Hau adds that while the alpha males show higher levels of stress-related hormones in their feces, this might be due to numerous short spikes of acute stress episodes rather than one long, continuous state of chronic stress such as humans low on the totem pole might face. Such acute spikes in stress hormones, Hau says, have been associated in previous research with higher healing rates, especially in the skin.
Bruce McEwen, a neuroendocrinologist at Rockefeller University in New York City, agrees. “An acute stress hormone response is likely to enhance adaptive immunity and wound healing, whereas the sluggish and prolonged elevation” of stress hormones “is likely to impair immune function.”
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发表于 2012-5-23 06:40:58 | 显示全部楼层
这么好的贴,竟然还没人抢沙发!这个时间是不是还没人醒呢~
发表于 2012-5-23 09:11:41 | 显示全部楼层
今天的文章好喜欢><。。。btw。。那只猴子好丑 长的像只马。。 0 0

1:36
研究老年痴呆症--开始组织 致力研究减缓组织---已被批准
2:15
大脑外伤对大脑的影响---通过研究2011日本地震海啸来推测结论---不知道是本身固有还是外来影响--因此研究大脑中容易受到影响的部分---过程是看图 挑人---这一段没有得出具体结论
2:25
得出结论:
肯定影响大脑了:1.对记忆部分影响不大2.对消除恐惧的部分影响较大。。。因此那些消除恐惧大脑缩小的students表现除了tense。。
最后展望了下未来:认为大脑真的很敏感啦 未来我们需要做点什么保护大脑啦。。


2:36
讲了一个人对美国对中美贸易资助的反对意见、
1P:1、那个人对中国人权critic 2、那个人认为钱没花在刀刃上 给中国给的太多了 花在美国更好 3、认为中美贸易太伤害美国了 又偷商业机密 又要美国赞助发展绿色经济 总之一句话 认为美国亏大了
2P:上升到中美关系了:两国一直若即若离 举例之前OBM撤销中国科技投资赞助---认为破坏了白宫在外交上的政策 尽管之后恢复---总之认为一切政策以美国利益为重


2:14
开始以为是美国调查认为病从口入
后来发现好像是正评价词汇 应该指有益的微生物细菌
1P:美国的饮食习惯结构与众不同
2P:切入主题发现人体内含有大量微生物 是细胞的1-10倍 它在我们人体中有这重要的作用--分解食品促进分子吸收等等  【提出argument:认为能够防御疾病】
3P:论证argument--做了个实验;取样-控制变量-等等
4P:得出结论 infants<adult 因为adult积攒的时间比较多。 最后论证结论 能够帮助防御疾病

自由阅读:1:38
扫了一下 大概是说评价次发现意义深远影响重大 但为了严谨性考虑 还需要继续深入发掘

5:13
要去上课了简略写一下
全文论证一个关系 高地位-高压力-高健康 由那个丑丑的猴子推人- -  因为高地位 肯定高压力 但是他们恢复的也快 因为他们资源多 所以他们更健康 对比组是低压力低地位的猴子or人
发表于 2012-5-23 10:53:29 | 显示全部楼层
谢谢LZ精彩的文章~~

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1’55

6‘
1.说免疫和治愈能力和地位在人类中是呈正相关,而在灵长类动物中是负相关
2.然后说了一个研究小组针对灵长类的问题又进行了研究,发现在灵长类动物中该关系也是正相关的
3.最后一段,跳出来一个人说了一个其他的结论,在人类中地位高的人受到的压力都是短暂的,而短暂的压力有助于提高免疫和治愈能力,相反,地位低的人长期受到压力,免疫和治愈能力反而受到影响
发表于 2012-5-23 11:07:20 | 显示全部楼层
今天的越障特别好,感觉思路和gmat很像,谢谢christine

0:53
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5:15
发表于 2012-5-23 11:51:53 | 显示全部楼层
喜欢今天的文章,谢谢christeen
42''    1'05''   46''   1'10''  1'01''  
4'20''
relationship among:
A. social-economic status
B. stress level
C. stress-related disease susceptibility (related to immune system)
in C and humans

a collaborative study: several groups, get samples from in Kenya, from 198X to 2009, hundreds of samples, ...

conclusion: not a simple story...
contra to previous belief, the high-order animals/people do have high stress, as low-order people do.
BUT the nature of the stress is different. Also, high-order animals/people can recover from stress more efficiently, have higher immune functions, and are less susceptible to stress-related disorders.
lead to a theory related to evolution...... high order animals are selected to be able to handle the stress level.
发表于 2012-5-23 12:51:20 | 显示全部楼层
1'54
2'51
2'06
1'48
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7'32
一些研究表明这个高压对人的健康又一定的好处
在狒狒身上的实验看出狒狒老的的得病率要低
一些研究也发现人类也有着同样的徵状
实验中狒狒体现出来的一些数据和现象
科学家怀疑是不是年龄因素也有关,但是最后还是认为这个高压室主要原因
高压导致身体健康的原因是因为人类和动物具有进化的适应性
高压环境下的人同样也有更好的缓解方式
其他一些科学家提出一些问题待解答

今天越障很好啊,稀饭稀饭
发表于 2012-5-23 15:36:41 | 显示全部楼层
1.35Alzheimer's disease的研究,专家们开会讨论,说了几个方面的计划步骤怎么解决
2.29灾难过后的心灵创伤让一些人有PTSD,专家对地震幸存者进行研究,看是否对大脑造成创伤
2.30对海啸幸存者进行测试,大脑中某个部分变小的话,在ptsd测试中的分数越高
2.48
2.28对microbe的研究,首先提出猜想它是导致人们体内不同的原因,分解营养让人体吸收,又有防细菌的作用,然后对不同地区的人进行研究,结果发现它随着人口年龄增长发生变化的方式差不多,不过年龄越大,之间的区别就越大。。
越障7.08
发表于 2012-5-23 19:54:33 | 显示全部楼层
1:07
1:59
1:31
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2min
~~
7:15
1.    chronic stress is bad for health, because it weakens the immume system.
2.    There is correlation in human between between social economic status and lower risk of death from stress-related disease.
3.    In animals, there is relation between stress and status, which are depend on social organization.
EX.baboon
4.    Study analyzing wild baboons
*oldest and lowest-ranking males are more likely to be ill, because of lower immune system.
5. age and rank can effect wound-healing time, but speed of wound-healing and size of social group also do.
*Members in bigger organization recover quicker than those in smaller ones.
#The phenomenon above can be applied to the group in NO.4
6.sth about the study....
发表于 2012-5-23 22:32:43 | 显示全部楼层
1. 1'32 专家们对老年痴呆症将来的研究,预计到2025完成这个研究。虽然有困难但是希望能和其他领域的专家一起配合治疗。obama已经批款。
2. 2‘17 专家研究外伤对脑子的影响。但是这个影响不好研究因为不知道是不是在受伤前就有区别。
3. 1’58 实验结果表明脑子某个部分小的更容易受情绪的影响。OC的变小是因为外伤本身,减少记忆力。
4. 2‘27 一个人提出美国和中国合资很疯狂。他说中国没有人权,这些钱花在美国更好,投资到中国后我们偷他们的技术。然后说两年前国会不同意和中国的任何在科技上的合作投资,但是obama不同意,后来国会让步了,obama只宣传这个投资的有益方面。
5. 2’26 美国是一个多文化的国家但是他们的内脏区别却不大。在他们的内脏里发现有许多细菌。这些细菌虽然有好处但是科学家怀疑也可能带来疾病。然后从美国不同的地区采集了不同年龄人的DNA来分析,结果是细菌成熟的过程是一样的。
6. 2‘10 上面那个实验还显示了M和V两个地方人内脏中的细菌比美国的多.这个是由美国的饮食结构造成的,美国人的细菌和食肉动物的更相似。但是这个细菌少对美国以后的人有什么影响却不知道,不一定少就不好。科学家会继续研究的。
7. 7’59 研究压力和免疫系统的关系。刚开始认为压力大会降低免疫力,然后对二者的关系进行研究。在狒狒界里,二者的关系是压力大和年龄都影响免疫力。排除了年龄的因素,发现压力大的狒狒有更好的免疫力。然后这个结果有人认为是可信的,讲了优点。
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