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Although food prices in major world markets are at or near a historical low, there is increasing concern about food security—the ability of the world to provide healthy and environmentally sustainable diets for all its peoples. This article is an introduction to a collection of reviews whose authors were asked to explore the major drivers affecting the food system between now and 2050. A first set of papers explores the main factors affecting the demand for food (population growth, changes in consumption patterns, the effects on the food system of urbanization and the importance of understanding income distributions) with a second examining trends in future food supply (crops, livestock, fisheries and aquaculture, and ‘wild food’). A third set explores exogenous factors affecting the food system (climate change, competition for water, energy and land, and how agriculture depends on and provides ecosystem services), while the final set explores cross-cutting themes (food system economics, food wastage and links with health). Two of the clearest conclusions that emerge from the collected papers are that major advances in sustainable food production and availability can be achieved with the concerted application of current technologies (given sufficient political will), and the importance of investing in research sooner rather than later to enable the food system to cope with both known and unknown challenges in the coming decades.  相似文献   

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The ~400 million specimens deposited across ~3000 herbaria are essential for: (i) understanding where plants have lived in the past, (ii) forecasting where they may live in the future, and (iii) delineating their conservation status. An open access ‘global metaherbarium’ is emerging as these specimens are digitized, mobilized, and interlinked online. This virtual biodiversity resource is attracting new users who are accelerating traditional applications of herbaria and generating basic and applied scientific innovations, including e-monographs and floras produced by diverse, interdisciplinary, and inclusive teams; robust machine-learning algorithms for species identification and phenotyping; collection and synthesis of ecological and genomic trait data at large spatiotemporal and phylogenetic scales; and exhibitions and installations that convey the beauty of plants and the value of herbaria in addressing broader societal issues.  相似文献   

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In only the past few decades, neuroscience has expanded beyond recognition, and shows no sign of slowing down. The problems for this ever-growing and increasingly fragmented field are matched only by its potentials. This article explores possible avenues of research and ethical debate that wait to be faced in the new Decade of the Mind.  相似文献   

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A report of the 2007 EMBO Conference Series on Plant Molecular Biology 'From basic genomics to systems biology', Ghent, Belgium, 2-4 May 2007.  相似文献   

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A project of an onboard medical support system (OMSS) for future aerospace system (ASS) flights is proposed. The following systems are suggested to be the main components of the OMSS: the basic system for automated estimation of blood redistribution (BSAEBR) in the body, protection and prophylactic means (PPM) for crew members, and the automated PPM control loop. The proposed BSAEBR includes four measurement channels for recording the basic physiological parameters (electrocardiogram, rheoencephalogram, venous-arterial pulsogram of neck blood vessels, and pulsogram of earlobe vessels), the changes in which are used to calculate, by means of a computer, the integrated parameter. The creation of lower body negative pressure (LBNP) was selected as a PPM. The automated PPM control loop individually selects the LBNP modes according to (1) the intensity of the body reactions and (2) individual characteristics of the physiological state. A working laboratory bench model of the OMSS has been manufactured and tested in two series of experiments simulating the conditions of a space flight. In the first series, 29 volunteers were exposed to ?10 deg antiorthostatic hypokinesia (ANOH) for 6–8 h, as well as ANOH + LBNP. In the second series, 26 volunteers were exposed to the combination of ANOH, Coriolis acceleration, and optokinetic stimulation every 5–7 h for three days. The results have demonstrated that the use of the given OMSS ensures, on average, a 17–32% improvement of the psychophysiological parameters of an operator, with the changes in the head circulatory parameters being more favorable.  相似文献   

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Major macroevolutionary events in the history of the oceans are linked to changes in oceanographic conditions and environments on regional to global scales. Even small changes in climate and productivity, such as those that occurred after the rise of the Isthmus of Panama, caused major changes in Caribbean coastal ecosystems and mass extinctions of major taxa. In contrast, massive influxes of carbon at the end of the Palaeocene caused intense global warming, ocean acidification, mass extinction throughout the deep sea and the worldwide disappearance of coral reefs. Today, overfishing, pollution and increases in greenhouse gases are causing comparably great changes to ocean environments and ecosystems. Some of these changes are potentially reversible on very short time scales, but warming and ocean acidification will intensify before they decline even with immediate reduction in emissions. There is an urgent need for immediate and decisive conservation action. Otherwise, another great mass extinction affecting all ocean ecosystems and comparable to the upheavals of the geological past appears inevitable.  相似文献   

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This article reviews the history and structure of the National Disaster Medical System (NDMS), with an emphasis on its definitive care component. NDMS's capacity to handle very large mass casualty events, such as those included in the National Planning Scenarios, is examined. Following Hurricane Katrina, Congress called for a reevaluation of NDMS. In that context, we make three key suggestions to improve NDMS's capacity to respond to large mass casualty disasters: (1) increase the level of engagement by the private (i.e., nonfederal) healthcare system in preparedness and response efforts; (2) increase the reliance on regional hospital collaborative networks as part of the backbone of the NDMS system; and (3) develop additional, alternative patient transportation systems, linked to the overall NDMS patient tracking effort, to decrease the sole reliance on DoD long-haul air transport in medical evacuation.  相似文献   

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The International Journal of Life Cycle Assessment -  相似文献   

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Energy from biomass plays a large and growing role in the global energy system. Energy from biomass can make significant contributions to reducing carbon emissions, especially from difficult‐to‐decarbonize sectors like aviation, heavy transport, and manufacturing. But land‐intensive bioenergy often entails substantial carbon emissions from land‐use change as well as production, harvesting, and transportation. In addition, land‐intensive bioenergy scales only with the utilization of vast amounts of land, a resource that is fundamentally limited in supply. Because of the land constraint, the intrinsically low yields of energy per unit of land area, and rapid technological progress in competing technologies, land intensive bioenergy makes the most sense as a transitional element of the global energy mix, playing an important role over the next few decades and then fading, probably after mid‐century. Managing an effective trajectory for land‐intensive bioenergy will require an unusual mix of policies and incentives that encourage appropriate utilization in the short term but minimize lock‐in in the longer term.  相似文献   

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