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The long-term response of coral reefs to climate change depends on the ability of reef-building coral symbioses to adapt or acclimatize to warmer temperatures, but there has been no direct evidence that such a response can occur. Here we show that corals containing unusual algal symbionts that are thermally tolerant and commonly associated with high-temperature environments are much more abundant on reefs that have been severely affected by recent climate change. This adaptive shift in symbiont communities indicates that these devastated reefs could be more resistant to future thermal stress, resulting in significantly longer extinction times for surviving corals than had been previously assumed. 相似文献
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Boyd PW Law CS Wong CS Nojiri Y Tsuda A Levasseur M Takeda S Rivkin R Harrison PJ Strzepek R Gower J McKay M Abraham E Arychuk M Barwell-Clarke J Crawford W Crawford D Hale M Harada K Johnson K Kiyosawa H Kudo I Marchetti A Miller W Needoba J Nishioka J Ogawa H Page J Robert M Saito H Sastri A Sherry N Soutar T Sutherland N Taira Y Whitney F Wong SK Yoshimura T 《Nature》2004,428(6982):549-553
Iron supply has a key role in stimulating phytoplankton blooms in high-nitrate low-chlorophyll oceanic waters. However, the fate of the carbon fixed by these blooms, and how efficiently it is exported into the ocean's interior, remains largely unknown. Here we report on the decline and fate of an iron-stimulated diatom bloom in the Gulf of Alaska. The bloom terminated on day 18, following the depletion of iron and then silicic acid, after which mixed-layer particulate organic carbon (POC) concentrations declined over six days. Increased particulate silica export via sinking diatoms was recorded in sediment traps at depths between 50 and 125 m from day 21, yet increased POC export was not evident until day 24. Only a small proportion of the mixed-layer POC was intercepted by the traps, with more than half of the mixed-layer POC deficit attributable to bacterial remineralization and mesozooplankton grazing. The depletion of silicic acid and the inefficient transfer of iron-increased POC below the permanent thermocline have major implications both for the biogeochemical interpretation of times of greater iron supply in the geological past, and also for proposed geo-engineering schemes to increase oceanic carbon sequestration. 相似文献
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Beardsley T 《Nature》1984,312(5996):686
The Monsanto Company will soon notify the Environmental Protection Agency (EPA) that it plans to conduct the first field test of a genetically-engineered microbial pesticide, thereby becoming the first company to break with the convention whereby private corporations have voluntarily sought approval for genetic engineering experiments from the Recombinant DNA Advisory Committee (RAC) of the National Institutes of Health (NIH). It is assumed that Monsanto's decision was influenced by a preliminary legal injunction blocking NIH approval of such field trials without a formal environmental assessment. EPA will allow tests, after 90 days' notice, if it raises no objections to the protocol. Although EPA will not formally call on RAC to examine the protocol, an agency spokesperson said there is "total agreement" between EPA and RAC on what data must be included. 相似文献
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Beardsley T 《Nature》1984,309(5969):574
The Data Protection Bill, which provides individuals the right of access to computerized data about themselves while preventing unauthorized disclosure of information, passed Britain's House of Commons at its third reading and returned to the House of Lords. Among the amendments added to the controversial legislation was one concerning the transfer of medical information to agencies outside the health system. After extensive lobbying by the medical community, the government agreed that a code of practice governing disclosure of medical data recently developed by an interprofessional working group should apply in principle to computerized records. 相似文献
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Beardsley T 《Nature》1984,307(5950):406
Britain's Genetic Manipulation Advisory Group (GMAG) is to be replaced by a new body, the Advisory Committee on Genetic Manipulation (ACGM), slated to consist of representatives of employers' and employees' organizations and technical experts. ACGM will address policy issues and will not review individual experiments, as did GMAG. Those doing individual research projects will instead report to the Health and Safety Executive. One of the first issues likely to be addressed by ACGM is the proposed release of genetically-engineered organisms into the environment. Some members of GMAG have pointed out that the new system does not provide for a permanent mechanism for considering ethical problems arising from new recombinant DNA techniques. 相似文献
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Replication of signals from recent studies of Crohn's disease identifies previously unknown disease loci for ulcerative colitis 总被引:1,自引:0,他引:1
Franke A Balschun T Karlsen TH Hedderich J May S Lu T Schuldt D Nikolaus S Rosenstiel P Krawczak M Schreiber S 《Nature genetics》2008,40(6):713-715
Following up on recent genome-wide association studies (GWAS) of Crohn's disease, we investigated 50 previously reported susceptibility loci in a German sample of individuals with Crohn's disease (n = 1,850) or ulcerative colitis (n = 1,103) and healthy controls (n = 1,817). Among these loci, we identified variants in 3p21.31, NKX2-3 and CCNY as susceptibility factors for both diseases, whereas variants in PTPN2, HERC2 and STAT3 were associated only with ulcerative colitis in our sample collection. 相似文献
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Taylor MS Massingham T Hayashizaki Y Carninci P Goldman N Semple CA 《Nature genetics》2008,40(11):1262-3; author reply 1263-4