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排序方式: 共有91条查询结果,搜索用时 15 毫秒
1.
Research relevance, 'knowledge transfer' and the geographies of CASE studentship collaboration 总被引:1,自引:0,他引:1
The Co-operative Awards in Science and Engineering (CASE) studentship programme of the UK Research Councils provide one example of wider efforts internationally to encourage so-called 'knowledge transfer' and thereby harness publicly supported university research more closely to the goals of national competitiveness, regional economic development and local regeneration. In this paper we describe the implications of how the various UK research councils have interpreted the objectives and beneficiaries of 'knowledge transfer', both for the relative opportunities available to human and physical geographers for collaboration through CASE and for the sorts of values that their research must serve. Then, we draw on unpublished data from the Economic and Social Research Council (ESRC) to explore the geographies of CASE studentship allocation and participation. The broad regional and institutional patterns of participation we describe have important implications for ongoing debates in the UK about research selectivity and the role of the university as an engine of local development, while the striking disciplinary patterns of CASE participation, and in particular the overwhelming success of geographers in this competitive programme, provide an opportunity to reassess claims about whether and for whom geographical research is relevant. 相似文献
2.
Sara Satolli Paolo Pace Mauro Gabriele Viandante Fernando Calamita 《International Journal of Earth Sciences》2014,103(8):2301-2313
In foreland thrust belts, abrupt lateral changes in tectonic style, structural–stratigraphic features, and topography usually occur across cross-strike faults. The Central Apennines of Italy offer an exceptional scenario of lateral variations in tectonic setting. Here, the Sangro Volturno oblique thrust ramp (SVOTR) represents the outer thrust front of the Pliocene–Quaternary foreland thrust system, confining southward the axial culmination of the orogen that occurs in the Central Apennines. We present an interpretation of the Pliocene–Quaternary evolution of this cross-strike fault through an integrated dataset including structural-geological mapping and subsurface onshore seismic reflection profiles. The interpretation of the structural framework is augmented by the analysis of low-temperature thermochronometers from 32 new sites extending across the subsurface transverse structure. As evidenced by seismic line interpretation, the localization and development of the SVOTR have been influenced by inherited extensional faults within a positive inversion tectonics context. The regional distribution of the maximum paleotemperature values across the SVOTR constrains the original extent of the allochthonous thrust sheet over all its hanging-wall and footwall blocks. The Pliocene–Quaternary thrusting and inversion of SVOTR caused the strong hanging-wall uplift, which brought to the complete erosion of the allochthonous units and the exhumation of the Adria units. The integrated analysis of low-temperature thermochronometers and structural evidence as applied in the study case can define the role of major cross-strike discontinuities in foreland thrust belts, by constraining and verifying their tectonics inversion significance and the amount of related exhumation. 相似文献
3.
Paolo Laj Andrea I. Flossmann Wolfram Wobrock Sandro Fuzzi Giordano Orsi Loretta Ricci Stephan Mertes Alfons Schwarzenbck Jost Heintzenberg Harry Ten Brink 《Atmospheric Research》2001,58(4):256
We investigated the partitioning of trace substances during the phase transition from supercooled to mixed-phase cloud induced by artificial seeding. Simultaneous determination of the concentrations of H2O2, NH3 and black carbon (BC) in both condensed and interstitial phases with high time resolution showed that the three species undergo different behaviour in the presence of a mixture of ice crystals and supercooled droplets. Both H2O2 and NH3 are efficiently scavenged by growing ice crystals, whereas BC stayed predominantly in the interstitial phase. In addition, the scavenging of H2O2 is driven by co-condensation with water vapour onto ice crystals while NH3 uptake into the ice phase is more efficient than co-condensation alone. The high solubility of NH4+ in the ice could explain this result. Finally, it appears that the H2O2–SO2 reaction is very slow in the ice phase with respect to the liquid phase. Our results are directly applicable for clouds undergoing limited riming. 相似文献
4.
5.
Eutrophication and species introductions have resulted in increased macroalgal biomass in coastal ecosystems around the globe. Macroalgal mats may compete with microphytobenthos (MPB) for light and nutrients and, due to their position in the canopy, have a negative impact on MPB biomass. We tested this effect by conducting a meta-analysis of prior experiments, as well as a comparative survey, and a macroalgal-removal manipulation in the coastal lagoons of the Virginia Coastal Reserve (VCR) on the eastern shore of Virginia (USA). In all cases, MPB biomass was estimated using benthic chlorophyll as a proxy. While prior individual studies documented impacts of macroalgae, when effect sizes were averaged across studies, there was no consistent effect of macroalgal biomass on MPB biomass. In the VCR, a non-native red macroalga, Gracilaria vermiculophylla, dominates intertidal mats and attains high biomasses at some sites. Nevertheless, MPB biomass was unrelated to macroalgal mass based on a survey of mudflats. Further, when macroalgae were experimentally manipulated on a mudflat using a before and after impact design, there was no change in MPB. Based on the meta-analysis, survey, and manipulation we conducted, macroalgal mats do not have a generalizable effect on MPB, interactions seem context-dependent, and in the VCR, the effects on MPB appear neutral. This finding is important given the significance of MPB in supporting food webs and other estuarine ecosystem functions, as well as the increasing frequency and intensity of macroalgal blooms. 相似文献
6.
Climatic Change - This study examines the climatic drivers of ice-off dates for lakes and rivers across the Northern Hemisphere. Most lakes and rivers have trended toward earlier ice-off dates over... 相似文献
7.
The mid Hudson River is a heterotrophic system where allochthonous inputs apparently fuel the largest proportion of secondary production and ecosystem metabolism. We have analyzed a 6-yr dataset collected quarterly at six stations spanning a 150-km reach to assess variability at inter- and intra-annual time scales and regional spatial scales. The major components of the lower food web: bacterial biomass, detrital particulate organic carbon (POC), and dissolved organic carbon (DOC), show surprisingly discordant patterns in temporal and spatial variability. Bacterial abundance shows significant variability at all three scales, but the interannual variability is by far the greatest. DOC concentrations showed greatest variability among years, with intra-annual and spatial variability roughly equal. Freshwater flow is commonly considered a major driving force in river-estuarine variability but simple discharge was not a strong predictor of any component of suspended matter or DOC. For organisms in the Hudson River food web, these multiple scales of variability indicate highly unpredictable food resources in time and space, and these fluctuations may contribute to the variability in higher trophic levels. 相似文献
8.
Luigi Boccia Pasquale Pace Giandomenico Amendola Giuseppe Di Massa 《GPS Solutions》2008,12(3):163-171
High-altitude platforms (HAPs) are a flexible and attractive technology for providing innovative wireless services. These
aerial platforms can be successfully employed for mobile or broadband communications and for disaster monitoring or response.
However, one of the open issues is whether HAP stations can provide reliable services without temporal outages owing to stratospheric
winds that can cause positional and attitude instabilities thus affecting the communication system operation. To counteract
this issue, one possible solution is to use reconfigurable antennas whose pointing direction can be adjusted depending on
the platform spatial orientation. However, this would require real-time three-axial attitude data. As a possible solution,
this paper will review the potential of GNSS-based attitude determination systems with reference to HAP stations. In particular,
it will be shown how the use of a particular class of low multipath and lightweight antennas can provide a high degree of
accuracy without altering the avionic ballast. 相似文献
9.
Emmanuelle Vennin Anthony Bouton Raphaël Bourillot Aurlie Pace Adeline Roche Arnaud Brayard Christophe Thomazo Aurelien Virgone Eric C. Gaucher Guy Desaubliaux Pieter T. Visscher 《Sedimentology》2019,66(1):165-204
The Bonneville Basin is a continental lacustrine system accommodating extensive microbial carbonate deposits corresponding to two distinct phases: the deep Lake Bonneville (30 000 to 11 500 14C bp ) and the shallow Great Salt Lake (since 11 500 14C bp ). A characterization of these microbial deposits and their associated sediments provides insights into their spatio‐temporal distribution patterns. The Bonneville phase preferentially displays vertical distribution of the microbial deposits resulting from high‐amplitude lake level variations. Due to the basin physiography, the microbial deposits were restricted to a narrow shoreline belt following Bonneville lake level variations. Carbonate production was more efficient during intervals of relative lake level stability as recorded by the formation of successive terraces. In contrast, the Great Salt Lake microbial deposits showed a great lateral distribution, linked to the modern flat bottom configuration. A low vertical distribution of the microbial deposits was the result of the shallow water depth combined with a low amplitude of lake level fluctuations. These younger microbial deposits display a higher diversity of fabrics and sizes. They are distributed along an extensive ‘shore to lake’ transect on a flat platform in relation to local and progressive accommodation space changes. Microbial deposits are temporally discontinuous throughout the lake history showing longer hiatuses during the Bonneville phase. The main parameters controlling the rate of carbonate production are related to the interaction between physical (kinetics of the mineral precipitation, lake water temperature and runoff), chemical (Ca2+, Mg2+ and HCO3? concentrations, Mg/Ca ratio, dilution and depletion) and/or biological (trophic) factors. The contrast in evolution of Lake Bonneville and Great Salt Lake microbial deposits during their lacustrine history leads to discussions on major chemical and climatic changes during this interval as well as the role of physiography. Furthermore, it provides novel insights into the composition, structure and formation of microbialite‐rich carbonate deposits under freshwater and hypersaline conditions. 相似文献
10.