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211.
James D. Goldberg MD Frank A. Chervenak Robert A. Lipman Richard L. Berkowitz 《黑龙江环境通报》1986,6(1):45-49
Arthrogryposis Multiplex Congenita (AMC) was suspected on ultrasound examination of a fetus at 30·5 weeks of gestation. The criteria for establishing this prenatal diagnosis as well as the importance of establishing the diagnosis at any gestational age are discussed. The diagnosis of AMC was confirmed at birth in this case. 相似文献
212.
213.
Mycoplasma pneumoniae is a pathogenic eubacterium lacking a cell wall. Three decades ago, a "rod", an intracellular cytoskeletal structure, was discovered that was assumed to define and stabilize the elongated cell shape. Later, by treatment with detergent, a "Triton shell" (i.e. a fraction of detergent-insoluble cell material) could be obtained, believed to contain additional cytoskeletal elements. Now, by application of a modified Triton X-100 treatment, we are able to demonstrate that M. pneumoniae possesses a cytoskeleton consisting of a blade-like rod and a peripheral lining located close to the inner face of the cytoplasmic membrane, exhibiting features of a highly regular network. Attached "stalks" may support the cytoplasmic membrane. The rod was connected to the cell periphery by "spokes" and showed a defined ultrastructure. Its proximal end was found to be attached to a wheel-like complex. Fibrils extended from the proximal end of the rod into the cytoplasm. 相似文献
214.
215.
Tiedemann R Moll K Paulus KB Scheer M Williot P Bartel R Gessner J Kirschbaum F 《Die Naturwissenschaften》2007,94(3):213-217
Recent molecular data on the maternally inherited mitochondrial (mt) DNA have challenged the traditional view that the now
extinct Baltic sturgeon population belonged to the European sturgeon Acipenser sturio. Instead, there is evidence that American sea sturgeon Acipenser oxyrinchus historically immigrated into the Baltic Sea. In this study, we test the hypothesis that A. oxyrinchus introgressed into, rather than replaced, the A. sturio population in the Baltic. We established four single nucleotide polymorphisms (SNPs) in the nuclear MHC II antigen gene with
a species-specific SNP pattern. Using an ancient DNA approach and two independent lines of molecular evidence (sequencing
of allele-specific clones, SNaPshot), we detected both A. sturio and A. oxyrinchus alleles in the available museum material of the now extinct Baltic sturgeon population. The hybrid nature of the Baltic population
was further confirmed by very high levels of heterozygosity. It had been previously postulated that the immigration of the
cold-adapted A. oxyrinchus into the Baltic occurred during the Medieval Little Ice Age, when temperature likely dropped below the degree inducing spawning
in A. sturio. Under this scenario, our new findings suggest that the genetic mosaic pattern in the Baltic sturgeon population (oxyrinchus mtDNA, sturio and oxyrinchus MHC alleles) is possibly caused by sex-biased introgression where spawning was largely restricted to immigrating American
females, while fertilization was predominantly achieved by abundant local European males. The hybrid nature of the former
Baltic sturgeon population should be taken into account in the current reintroduction measures.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
216.
John Cosgrove Frank Doyle John Littlewood Paul Wilgeroth 《International Journal of Sustainable Engineering》2017,10(4-5):233-240
AbstractEnergy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland. 相似文献
217.
Different perceptions of adaptation to climate change: a mental model approach applied to the evidence from expert interviews 总被引:1,自引:1,他引:1
Ilona Otto-Banaszak Piotr Matczak Justus Wesseler Frank Wechsung 《Regional Environmental Change》2011,11(2):217-228
We argue that differences in the perception and governance of adaptation to climate change and extreme weather events are
related to sets of beliefs and concepts through which people understand the environment and which are used to solve the problems
they face (mental models). Using data gathered in 31 in-depth interviews with adaptation experts in Europe, we identify five
basic stakeholder groups whose divergent aims and logic can be related to different mental models they use: advocacy groups,
administration, politicians, researchers, and media and the public. Each of these groups uses specific interpretations of
climate change and specifies how to deal with climate change impacts. We suggest that a deeper understanding and follow-up
of the identified mental models might be useful for the design of any stakeholder involvement in future climate impact research
processes. It might also foster consensus building about adequate adaptation measures against climate threats in a society. 相似文献
218.
Marcos A. Lana Frank Eulenstein Sandro Schlindwein Edgardo Guevara Santiago Meira Angelika Wurbs Stefan Sieber Nikolai Svoboda Michelle Bonatti 《Regional Environmental Change》2016,16(5):1319-1331
Understanding climate change and its impacts on crops is crucial to determine adaptation strategies. Simulations of climate change impacts on agricultural systems are often run for individual sites. Nevertheless, the scaling up of crop model results can bring a more complete picture, providing better inputs for the decision-making process. The objective of this paper was to present a procedure to assess the regional impacts of climate scenarios on maize production, as well as the effect of crop cultivars and planting dates as an adaptation strategy. The focus region is Santa Catarina State, Brazil. The identification of agricultural areas cultivated with annual crops was done for the whole state, followed by the coupling of soil and weather information necessary for the crop modeling procedure (using crop model and regional circulation models). The impact on maize yields, so as the effect of adaptation strategies, was calculated for the 2012–2040 period assuming different maize cultivars and planting dates. Results showed that the exclusion of non-agricultural areas allowed the crop model to correctly simulate local and regional production. Simulations run without adaptation strategies for the 2012–2040 period showed reductions of 11.5–13.5 % in total maize production, depending on the cultivar. By using the best cultivar for each agricultural area, total state production was increased by 6 %; when using both adaptation strategies—cultivar and best planting date—total production increased by 15 %. This analysis showed that cultivar and planting date are feasible adaptation strategies to mitigate deleterious effects of climate scenarios, and crop models can be successfully used for regional assessments. 相似文献
219.
Tobias Conradt Hagen Koch Fred F. Hattermann Frank Wechsung 《Regional Environmental Change》2012,12(3):649-661
A global change assessment required detailed simulation of water availability in the Elbe River basin in Central Europe (148,268?km2). Using the spatially semi-distributed, eco-hydrological model SWIM, spatial calibration was applied. For 225 sub-areas covering the model domain (134,890?km2), evapotranspiration and groundwater dynamics were individually adjusted. The calibration aimed at good correspondences with long-term run-off contributions and the hydrographs for two extreme years. Measured run-off was revised from water management effects to produce quasi-natural discharges for calibration. At some gauges, there were large volume differences between these reference data and the simulations of the spatially uncalibrated model. Most affected were some sub-basins in the Czech part of the basin where the density of available climate stations was much lower than the German part. Thus, both erroneous precipitation data and systematic flaws in the evapotranspiration module of SWIM could have caused the differences. In order to identify the major error source and to validate the choice of spatial calibration parameters (evapotranspiration and groundwater dynamic corrections), MCMC analyses were made for three Czech areas. Optional precipitation correction had been considered by a third calibration parameter in the MCMC assessment. In two of the three cases, it can be shown that evapotranspiration corrections are preferable as precipitation errors are negligible. In the third case, where the analyses indicate a substantial error in precipitation data, an interpolation problem of the climate data at the edge of the model domain could be found. Hence, the applied method shows its potential to identify specific sources of uncertainty in hydrological modelling. 相似文献
220.
Williams Paula Alessa Lilian Abatzoglou John T. Kliskey Andrew Witmer Frank Lee Olivia Trammell Jamie Beaujean Grace Venema Rieken 《Regional Environmental Change》2018,18(2):547-559
Regional Environmental Change - Many papers have addressed the differing approaches to observation by scientists collecting instrumented data and by community or local knowledge-based observations.... 相似文献