四川生殖健康研究附属医院做人流
时间:2019年09月23日 13:56:37

学习记忆易受创,短期压力勿小觑Short-term stress lasting as little as a few hours can impair brain-cell communication in areas associated with learning and memory, University of California, Irvine researchers have found.It has been known that severe stress lasting weeks or months can impair cell communication in the brain's learning and memory region, but this study provides the first evidence that short-term stress has the same effect."Stress is a constant in our lives and cannot be avoided," said Dr. Tallie Z. Baram, the Danette Shepard Chair in Neurological Sciences in the UC Irvine School of Medicine and study leader. "Our findings can play an important role in the current development of drugs that might prevent these undesirable effects and offer insights into why some people are forgetful or have difficulty retaining information during stressful situations."In their study, Baram and her UC Irvine colleagues identified a novel process by which stress caused these effects. They found that rather than involving the widely known stress hormone cortisol, which circulates throughout the body, acute stress activated selective molecules called corticotropin releasing hormones, which disrupted the process by which the brain collects and stores memories.Learning and memory take place at synapses, which are junctions through which brain cells communicate. These synapses reside on specialized branchlike protrusions on neurons called dendritic spines.In rat and mouse studies, Baram's group saw that the release of CRH in the hippocampus, the brain's primary learning and memory center, led to the rapid disintegration of these dendritic spines, which in turn limited the ability of synapses to collect and store memories.The researchers discovered that blocking the CRH molecules' interaction with their receptor molecules eliminated stress damage to dendritic spines in the hippocampal cells involved with learning and memory.In addition, the authors replicated the effects of stress on dendritic spines by administering low levels of synthetic CRH, and watching how the spines retracted over minutes. "Fortunately, once we removed the CRH, the spines seemed to grow back," Baram said.Baram also noted that there are compounds under development that show the ability to block CRH receptors, and that this study can play a role in the creation of therapies based on these compounds to address stress-related learning and memory loss.The study appears in the March 12 edition of the Journal of Neuroscience. Yuncai Chen, Celine Dubé and Courtney Burgdorff of UC Irvine also participated in the study, which was supported by the National Institutes of Health. 加州大学欧文分校研究人员发现,即使只是几小时的短期压力也扰乱脑细胞间的正常运作,而这些运作正关系到学习和记忆。我们知道,持续长达几周甚至几个月的强大压力会对大脑学习和记忆区域的神经细胞传导造成损害。但是这次实验第一次发现,短期压力也会产生同样的破坏力。加州大学欧文分校医学院神经科学Danette Shepard 主席,这次研究的领导者,Tallie Z. Baram士说道:“我们的生活中到处都存在着压力,躲也躲不了。我们这次的研究成果将起到非常重要的作用。根据这些研究成果,我们可以制造新的药物以减轻不良影响,并且深入探究有些人为什么在压力下容易健忘或者出现问题。”在这次研究中,Baram及他的同事还发现了一个新细节,而压力正是通过这个途径来产生副作用的。他们发现,影响学习和记忆的并不是由人们熟知的遍布全身的激素皮质醇造成的,而是强大的压力激发了一部分分子(促肾上腺皮质激素),由它所释放的荷尔蒙扰乱了大脑收集、储存信息的过程。当神经元的突触(两个神经元之间或神经元与效应器细胞之间相互接触、并借以传递信息的部位)传递信息时,人们才能进行学习和记忆。这些突触存在于神经元的突出(树突刺)这样的特殊神经元分上。在鼠科动物试验中,Baram研究组发现海马体(大脑皮质的一个内褶区,进行学习和记忆的地方)中促肾上腺皮质激素的释放迅速破坏了树突刺,这样便影响了突触对信息的收集和储存。研究还发现,用促肾上腺皮质激素受体分子阻止激素之间的相互作用可以消除压力对海马体细胞树突刺的伤害。除此之外,研究者们还通过注射少量的合成促肾上腺皮质激素模拟压力对树突刺的影响,观察树突刺在几分钟内收缩的状况。Baram说:“幸运的是,当我们移除促肾上腺皮质激素的时候,树突刺又恢复了原来的样子。”Baram还提到他们正在研究一种物质,它能阻止促肾上腺皮质激素受体的运作,而且这次研究为一种全新疗法的发明奠定了良好的理论基础。这种疗法以正在研究的物质为基础,且能处理由压力导致的学习及记忆损害的问题。这篇报告刊登在3月12日《神经科学杂志》上,加州大学欧文分校的Yuncai Chen, Celine Dubé 和 Courtney Burgdorff也参与了此次研究。此次研究由美国国立卫生研究院赞助持。 /200803/31404

This year’s US election has given rise to plenty of peculiar developments. 今年的美国大选引发了很多奇怪的事态。Here is another one: Carbon Black, a cyber security firm, has released a poll suggesting that 58 per cent of voters think it likely that electronic voting machines could be cyber-hacked. 这里又有一样:网络安全公司Carbon Black公布民调显示,58%的选民认为电子投票器被入侵的可能性较大。Indeed, popular concern is so high that 15m voters may refuse to participate, Carbon Black says, noting that voters believe a US insider threat (28 per cent), Russia (17 per cent) and the candidates themselves (15 per cent) pose the biggest risks.Carbon Black称,事实上,公众担忧之甚,以至于1500万选民可能会拒绝参加投票。该公司指出,选民认为美国内部人士(28%)、俄罗斯(17%)和候选人本身(15%)是前几大构成风险的危险因素。It might seem tempting to dismiss this as marketing, or as a sign of the febrile political mood, but discounting that 58 per cent number that would be a terrible mistake. 我们可能很容易想把上述结果简单地归结为一种营销造势,或一个显示狂热政治情绪的标志,但是忽视这个58%的数字将是个严重的错误。One reason is that many US government officials quietly share voters’ concerns. 一个原因是,美国很多政府官员私底下也存在与选民们相同的担忧。Little wonder. 这也难怪。Small cyber breaches of the electoral register have aly occurred in Arizona and Illinois. 亚利桑那州和伊利诺伊州的选民名册数据库已经遭到过小规模入侵。Several states are thought to be vulnerable to attacks on the election system, particularly those, like Pennsylvania, that use direct-recording electronic machines to tally the vote. 多个州的选举投票系统被认为容易受到攻击,特别是那些使用直接记录电子机器来计票的州,比如宾夕法尼亚州。Pennsylvania, largely thought to be a key battleground state in the upcoming election, may be the largest concern when it comes to electronic voting machines, Carbon Black suggests.Carbon Black指出:宾州在即将举行的大选中被认为是关键战场,而这个州的电子投票器可能是最令人担忧的。Even if election fears turn out to be misplaced, they highlight a bigger point: a new front is opening up in cyber warfare. 即便关于大选的担忧到头来原来是多虑,它们也突显了更重要的一点:一条新战线正在网络战争中打开。This has big implications for both political pundits and business leaders.这对政治专家和商界领袖影响重大。Two decades ago, it was presumed that hackers aimed to do one of four things: steal money; grab secrets; highlight a political cause; or inflict physical sabotage. 二十年前,人们认定黑客的目标无非是做以下四件事之一:偷钱、窃取情报、促使世人关注某项政治事业、或造成实际的破坏。Western intelligence forces have moved to offset those threats. 西方情报部门已采取行动来消除这些威胁。For example, the Federal Bureau of Investigation and Department of Homeland Security are currently running a cyber security awareness month to teach consumers and businesses how to avoid fraud and theft. 例如,美国联邦调查局(FBI)和国土安全局(DHS)目前正在开展网络安全意识月活动,教消费者和企业如何避免遭受欺诈和盗窃。Meanwhile, the US military and DHS have been scrambled to protect so-called systemically important infrastructure from sabotage. 与此同时,美国军队和国土安全局争相保护所谓具有系统重要性的基础设施免遭破坏。There is intense activity around the US electricity grid, after hackers damaged a Ukrainian grid last year.在去年黑客破坏乌克兰电网后,针对美国电网也存在密集的黑客活动。The US election has put a fifth category of risks on the radar: cyber attacks that aim to inflict psychological damage by shattering public trust. 美国大选将第五种风险带到了人们的视线中:旨在通过动摇公众信任而造成心理上的破坏的网络攻击。People have got it all wrong, Dmitri Alperovitch, founder of cyber security group CrowdStrike, recently told me. 人们全搞错了,网络安全公司CrowdStrike的创始人德米特里#8226;阿尔佩罗维奇(Dmitri Alperovitch)最近向我表示。(CrowdStrike revealed that hackers, apparently linked to Russia, had infiltrated the Democratic National Committee.)(CrowdStrike透露,看上去与俄罗斯有关联的黑客之前已渗入过民主党全国委员会(DNC)的网络)。For the past 30 years everyone has worried about kinetic attacks, say an attack on a grid — we were waiting for a cyber Pearl Harbor. 过去30年,每个人都担心动力受到攻击、也就是电网受到攻击——我们一直在等待一场网络珍珠港事件。But the Russians have always believed that the real value of cyber is psychological warfare and influence.但是俄罗斯人始终认为,网络的真正价值在于心理方面的战争和影响力。As a senior US intelligence figure recently told a private meeting of business and policy luminaries: What do we do if the key goal of cyber hackers now is not to steal things but undermine trust in things that guide our lives? Intelligence officials are particularly uneasy about the risk of an attack on the financial system, since this is a sector which only functions if there is trust — as the crisis of 2008 showed.正如美国一名高级情报官员最近在一次商界和政界名流齐聚的私人会议上所说的那样:如果现在网络黑客的核心目标不再是偷东西、而是破坏我们对指引我们生活的东西的信任,我们怎么办?情报官员格外担忧黑客会攻击金融系统,因为金融是一个只有在存在信任的情况下才能正常运行的领域——正如2008年金融危机所显示的那样。American officials are trying to fight back. 美国官员正尝试反击。Last weekend, for example, the DHS offered to provide cyber security assistance to state governments to help them protect the election. 例如,国土安全局近日表示愿向各个州政府提供网络安全协助,帮助各州保护大选免受网络攻击。Two dozen states have accepted. 24个州接受了。But the election is so close, and states so cash-strapped, that it is unclear how effective these defences will be. 但是大选日期近在咫尺,许多州又如此囊中羞涩,这些防御措施的效果如何尚不清楚。Bafflingly, the DHS has not designated the electoral register as critical infrastructure. 令人困惑的是,国土安全局并没有把选民名册定为关键基础设施。It should do this now, so Federal funds can be released for the fight.该部门现在应该这么做,这样才能让联邦资金得以被用于打赢这场仗。The really big issue, though, is the psychological threat. 不过,真正要紧的问题是心理威胁。Donald Trump has called for aggressive counter-attacks in cyber space to provide a display of strength. 唐纳德#8226;特朗普(Donald Trump)呼吁在网络空间发动强硬反击,让对手知道厉害。Separately, Mr Alperovitch thinks the US government needs to publicly declare that Russia is launching psychological attacks, in order to prepare the public. 此外,阿尔佩罗维奇认为,美国政府需要公开宣布俄罗斯正在发动心理攻击,从而让公众做好心理准备。In the cold war days, the state department had a department which countered Soviet propaganda, but then it was disbanded, he argues. They need to once again build a strategy for countering Russia’s aggressive influence operations.在冷战期间,美国国务院曾设有一个部门负责反击苏联的宣传,但后来解散了,他认为,他们需要再次构建起一套战略来对抗俄罗斯咄咄逼人的造势活动。The risk of any aggressive action is that it might launch bigger counter-attacks or sp public fear. 采取任何激进行动的风险是,可能引发更猛烈的反击或在公众中散播恐惧情绪。American voters and politicians seem stuck in a nervous waiting game. 美国选民和政治人士似乎卡在了紧张的等待中进退两难。We had better hope that eventually a new form of cold war-style detente emerges in 21st-century cyber space, as it once did in the physical world. 我们最好希望,在21世纪的网络空间中,也能出现一种新的休战——就像曾经在现实世界中出现过的、为冷战画上了句号的那种。If not, business leaders need to look at the US election — and prepare for a world where digital trust is a new military plaything.如果没出现,那么商界领袖需要关注美国大选,并准备好迎接这样一个世界,在这个世界里,数字空间里的信任成为新的被玩弄的对象。 /201610/470239

Xiaomi has sealed a deal to buy some 1,500 patents from Microsoft, a move that will help the Chinese smartphone maker expand exports and earn the US technology giant some badly needed goodwill in Beijing.小米(Xiaomi)与微软(Microsoft)达成一项协议,将向微软购买约1500项专利,此举将帮助这家中国智能手机制造商扩大出口,并为这家美国科技巨头在中国获得一些亟需的商誉。The transaction addresses a key weakness facing Xiaomi, which is seeking to sell its devices in countries outside its home market but has been hindered by its relative lack of intellectual property to fend off lawsuits.这笔交易化解了小米面临的一项主要弱势,该公司希望在本土市场以外的国家销售其产品,但由于相对缺乏知识产权来抵御诉讼,这方面的努力受阻。“In terms of patents we are a young company,” Xiaomi said yesterday, adding that the Microsoft deal was “a big milestone for us. It will help us with operations in new markets.”“从专利的角度来看,我们是一家年轻公司,”小米昨日表示,该公司补充称,与微软的协议“是我们的一项重要里程碑。它将有利于我们在新市场的业务。”The agreement comes on the eve of a visit to Beijing by Microsoft chief executive Satya Nadella. The US company is still the subject of an antitrust investigation in China over the bundling of software, and its offices were raided by Chinese authorities in July 2014.该协议是在微软首席执行官萨蒂亚#8226;纳德拉(Satya Nadella)访华前夕签订的。微软仍因软件捆绑问题在中国面临反垄断调查,2014年7月,中国当局曾突击搜查该公司驻华办事处。The patents deal includes Xiaomi installing Microsoft’s Office and Skype software on its phones. Financial terms were not made public.这项专利协议包括小米将在其手机上安装微软的Office和Skype软件。交易金额没有公开。Xiang Wang, senior vice-president, said Xiaomi was “excited” to be working with Microsoft and the deal demonstrated the Chinese company was “looking to build sustainable, long-term partnerships with global technology leaders”.小米高级副总裁王翔表示,小米对于与微软合作感到“激动”,该协议明,小米“希望与全球科技领军企业建立可持续的长期合作”。Other US tech groups facing setbacks in China have looked to do deals with local champions, partly as a way to win favour with Beijing. Last month Apple invested bn in Didi Chuxing, China’s version of Uber, which some analysts said they believed was at least partly motivated by government relations.其他在中国受挫的美国科技集团也已寻求与中国冠军企业做生意,在一定程度上是为了赢得中国政府的青睐。上月,苹果(Apple)向中国版优步(Uber)滴滴出行(Didi Chuxing)投资10亿美元,一些分析人士表示,他们认为,此举至少在一定程度上受到政府关系的驱使。Xiaomi said it had applied for 5,700 patents over the past two years but declined to give any detail on the number it has been awarded and where. The deal was a drop in the bucket for Microsoft, with its 60,000 patents.小米表示,过去两年该公司已申请5700项专利,但拒绝透露有关获得批准的专利数量以及在何处获批的详细数据。对于拥有6万项专利的微软而言,该协议只是很小的一部分。A lean patent portfolio has hindered Xiaomi’s efforts to ramp up exports. In the smartphone industry, patent litigation is a serious challenge and access to a large number of patents allows companies to reduce their vulnerability to lawsuits by cross-licensing and trading patents.专利组合薄弱迄今阻碍着小米扩大出口的努力。在智能手机领域,专利诉讼是一项严峻挑战,获得大量专利将让公司通过交叉许可和专利交易减少诉讼带来的影响。In India, its largest prospective foreign market, Xiaomi last year faced a patent lawsuit in a Delhi High Court by Swedish telecoms equipment maker Ericsson.在印度,瑞典电信设备制造商爱立信(Ericsson)去年在德里高院(Delhi High Court)起诉小米专利侵权。印度是小米最具潜力的海外市场。The case continues, though Xiaomi won a reprieve in a subsequent ruling barring it only from importing and selling phones containing components linked to the Ericsson dispute.该案仍在审理中,尽管小米在随后的裁决中赢得喘息空间,仅被禁止进口和销售含有与爱立信纠纷相关的部件的手机。Xiaomi currently exports to seven countries outside of China and Hong Kong, including Malaysia, India and Brazil.除了中国内地和香港以外,小米目前还向7个国家销售产品,包括马来西亚、印度和巴西。Expanding exports is part of a strategy to bolster sales, which are sagging in China. Xiaomi was the best-selling smartphone brand in China in 2014 and part of 2015 but has been eclipsed by Shenzhen-based rival Huawei.扩大出口是提升销售的战略的一部分,如今小米在中国销售疲弱。在2014年全年和2015年部分时期,小米曾是中国最畅销的智能手机品牌,但现在已被总部位于深圳的竞争对手华为(Huawei)超越。Xiaomi sold more than 70m phones in 2015, up from 61m the year before but missing both its original target of 100m and a revised goal of 80m.小米在2015年销售了逾7000万部手机,超过了2014年的6100万部,但没有实现最初制定的销售1亿部(后来调整为8000万部)的目标。Microsoft itself has had little success in trying to crack the global smartphone market. It acquired Nokia’s hardware business in 2013 for .2bn but the deal has been disastrous. Microsoft said last month it would take an additional 0m writedown, having aly written down .6bn from its mobile phone operations and laid off 7,800 staff.微软自己在进军全球智能手机市场方面乏善可陈。它在2013年斥资72亿美元收购了诺基亚(Nokia)的硬件业务,但该交易是灾难性的。微软上月表示,将再次减记9.5亿美元,它之前已经对其手机业务减记了76亿美元,并裁掉了7800名员工。Bryan Ma at IT consultancy IDC in Singapore said of the deal: “It’s a win-win, with one side building up its patent collection and the other building up its ecosystem. But this deal alone won’t change either of their fortunes overnight.”新加坡IT咨询公司IDC的马伯远(Bryan Ma)谈到该交易时表示:“这是一笔双赢交易,让一方积累专利数量,另一方打造其生态系统。但单凭该协议不会在一夜之间改变它们的命运。” /201606/447439

Microsoft president Brad Smith slammed the National Security Agency (NSA) for its part in the WannaCry ransomware cyberattack.软件巨头微软公司总裁兼首席法务官布拉德·史密斯近日抨击美国国家安全局在“想哭”勒索软件网络攻击事件中扮演的角色。The malware behind the WannaCry was reported to have been stolen from the NSA in April.有报道称,“想哭”背后的恶意软件是今年4月从美国国安局偷走的。Smith, who is also the chief legal officer with the software giant, equated the NSA losing the hacking tool used in creating WannaCry as being the same as the US military losing a Tomahawk missile.史密斯称,美国国安局丢失了这个被用来创建;想哭;的黑客工具,相当于美国军方丢失了一枚战斧导弹。;We have seen vulnerabilities stored by the CIA show up on WikiLeaks, and now this vulnerability stolen from the NSA has affected customers around the world,; said Smith in a company blog.他在公司客上发文称:“我们已看到维基解密上晒出的中情局囤积的那些漏洞,如今这个美国国安局失窃的漏洞已对全球客户构成影响。”;Repeatedly, exploits in the hands of governments have leaked into the public domain and caused widesp damage.;“政府掌握的漏洞屡次流入公共领域,造成大范围的破坏。”The malicious software has created havoc on computer networks in more than 150 countries since May 12th.自5月12日以来,恶意软件“想哭”已对逾150个国家的计算机网络造成严重破坏。 /201705/510395


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