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291.
Eva K. Grebel 《Astrophysics and Space Science》2003,284(2):947-956
A selection of future observing facilities relevant to galaxy evolution science covering the wavelength range from X-rays
to the radio regime are summarized. Scientific aspects that can be investigated with these next generation telescopes are
briefly discussed. While prospects look bright for highly advanced and innovative future facilities, it will be important
to ensure that human resources in observational astronomy and theory – both in terms of expertise, funding, and available
positions – are keeping pace with the technological developments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
292.
Comparison of modelled- and remote sensing- derived daily snow line altitudes at Ulugh Muztagh,northern Tibetan Plateau 总被引:1,自引:0,他引:1
The ice cap Ulugh Muztagh in the central Kunlun Shan at the northern fringe of the Tibetan Plateau is a very isolated region with arid cold conditions. No observational, meteorological or glaciological ground truth data is available. Using the Moderate-resolution Imaging Spectroradiometer(MODIS) Level 1 radiance Swath Data(MOD02QKM) with a spatial resolution of 250 m, transient snow lines during the months of July to September in 2001 to 2014 are derived. Results are used to calibrate the physical based Coupled Snowpack and Ice surface energy and Mass balance model(COSIMA). The model runs on a representative detail region of Ulugh Muztagh(UM) on a digital elevation model with the same spatial resolution as the MODIS bands. In the absence of field observations, the model is driven solely by dynamically downscaled global analysis data from the High Asia Refined analysis(HAR). We compare remote sensing derived and modelled mean regional transient snow line altitudes in the course of consecutive summer seasons in 2008 to 2010. The resulting snow line altitude(SLA) and annual equilibrium line altitude(ELA) proxy of both methods coincide very well in their interannual variability in accordance with interannual variability of climatic conditions. Since SLAs of both methods do notconsistently agree on a daily basis a usage of remote sensing derived SLAs for model calibration in the absence of field observation data is only limitedly feasible for daily analysis. ELA approximation using the highest SLA at the end of ablation period may not be applied to UM because the negative winter mass balance(MB) is not reflected in the summer SLA. The study reveals moderate negative MB for UM throughout the modelling period. The mean regional MB of UM accounts for-523±410 mm w.e. a-1 in the modelling period. Hence UM seems not to belong to the area of the ‘Karakorum anomaly' comprising a region of positive mass balances in recent years which has its centre presumably in the Western Kunlun Shan. 相似文献
293.
Laura?CunninghamEmail author Kevin?Bishop Eva?Mett?vainio Peter?Rosén 《Journal of Paleolimnology》2011,45(4):507-518
A decade of widespread increases in surface water concentrations of total organic carbon (TOC) in some regions has raised
questions about longer term patterns in this important constituent of water chemistry. This study uses near-infrared spectroscopy
(NIRS) to infer lake water TOC far beyond the decade or two of observational data generally available. An expanded calibration
dataset of 140 lakes across Sweden covering a TOC gradient from 0.7 to 24.7 mg L−1 was used to establish a relationship between the NIRS signal from surface sediments (0–0.5 cm) and the TOC concentration
of the water mass. Internal cross-validation of the model resulted in an R
2 of 0.72 with a root mean squared error of calibration (RMSECV) of 2.6 mg L−1. The TOC concentrations reconstructed from surface sediments in four Swedish lakes were typically within the range of concentrations
observed in the monitoring data during the period represented by each sediment layer. TOC reconstructions from the full sediment
cores of four lakes indicated that TOC concentrations were approximately twice as high a century ago. 相似文献
294.
The capacity of coast recovering after interruption of pollution sources has been explored employing mussels as biomarkers.
In an area polluted by sewage sludge in Puerto Madryn (Argentina), abnormally high cytogenetic records (micronuclei) had been
detected in the mussel Mytilus edulis, even higher than those obtained in this and other mussel species (Brachydontes rodriguezi, Aulacomya atra atra, Perumytilus purpuratus) sampled from heavily polluted industrial areas, and much higher than those recorded in samples from unpolluted areas of
the same region. Normal cytogenetic patterns were recovered in Puerto Madryn less than 1 year after cessation of sewage sludge
discharges, without additional treatment of the affected area. This discovery opens the possibility of considering restored
coastal areas for aquaculture purposes instead of endangering natural populations in virgin areas. 相似文献
295.
296.
Paolo Citton Ausonio Ronchi Simone Maganuco Martina Caratelli Umberto Nicosia Eva Sacchi Marco Romano 《Geological Journal》2019,54(4):2084-2098
The Torre del Porticciolo palaeontological locality (Alghero, north‐west Sardinia, Italy) is important for having provided the skeletal remains of the first Permian basal synapsid from Italy, Alierasaurus ronchii, the largest late early Permian to early middle Permian non‐therapsid synapsid known to date. Recently, other skeletal remains preliminarily attributed to a carnivorous non‐therapsid synapsid were described from a second site, approximately from the same stratigraphic level within the Cala del Vino Fm. During the excavation of this second site, tetrapod tracks were found near Cala Viola, about 1 km from the first two sites. The new find represents the first ichnological record from the Permian of Sardinia. The ichnological analysis allowed the recognition of tetrapods presently not recognized, just on the base of skeletal remains. This new evidence sheds more light on the faunal diversity within the Cala del Vino Fm., which is one of the few examples in the Permian of Europe of a combined ichno‐ and body‐fossil record. The tracks have been referred to as Merifontichnus, an ichnotaxon established from the uppermost portion of the Permian succession of the Lodève Basin in southern France. The new material is the first reliable occurrence of this ichnotaxon from Italy and would represent, to date, the oldest occurrence of the ichnogenus. 相似文献
297.
Inhalt Hornblenden aus Eklogiten und Amphiboliten der südlichen Koralpe werden chemisch und optisch untersucht; außerdem sind die Gitterkonstanten der Hornblenden bestimmt worden.Herrn Prof. Dr.K. H. Scheumann in Verehrung zum 80. Geburtstag gewidmet. 相似文献
298.
Geographic information has a great potential to be re-used when supported by mechanisms for its discovery. Above all, the quality of a catalogue service is the key feature supporting users in the discovery process. So far, there have been in existence various methodologies dealing with the normalized evaluation of quality with respect to catalogue services. Their biggest weakness seems to be in the depth of quality testing, i.e. some influences are beyond the scope of evaluation of these methodologies with respect to quality in catalogue services. In this study, the quality of 45 catalogue services across Europe was verified with the proposed normalized evaluation methodology originating from documents within the INfrastruture for SPatial InfoRmation in Europe (INSPIRE) framework. This paper discusses the (statistical) influence of factors that may significantly change the results of catalogue service testing. The proposals for improving the existing INSPIRE normalized evaluation procedure are applicable for any spatial data infrastructure and/or Digital Earth component using the Open Geospatial Consortium Catalogue Service for the Web as a basis. 相似文献
299.
Kristien Ooms Philippe De Maeyer Veerle Fack Eva Van Assche Frank Witlox 《International journal of geographical information science》2013,27(10):1773-1788
The experiments described in this article combine response time measurements and eye movement data to gain insight into the users' cognitive processes while working with dynamic and interactive maps. Experts and novices participated in a user study with a ‘between user’ design. Twenty screen maps were presented in a random order to each participant, on which he had to execute a visual search. The combined information of the button actions and eye tracker reveals that both user groups showed a similar pattern in the time intervals needed to locate the subsequent names. From this pattern, information about the users' cognitive load could be derived: use of working memory, learning effect and so on. Moreover, the response times also showed that experts were significantly faster in finding the names in the map image. This is further explained by the eye movement metrics: experts had significantly shorter fixations and more fixations per second meaning that they could interpret a larger part of the map in the same amount of time. As a consequence, they could locate objects in the map image more efficiently and thus faster. 相似文献
300.
Throughout the shores of the world,a confluence of different sources of pollution is common,e.g.,through outlets releasing brine,industrial,and domestic sewage.In this study,we assessed whether a combined disposal of domestic sewage and brine altered the patterns of abundance and assemblage structure of subtidal macrofauna inhabiting sandy seabeds on the south coast of Gran Canaria(Canary Islands,NE Atlantic Ocean).Samples were collected in two surveys(May 2008 and January 2009)at three distances(0,15,and30 m)away from the discharge point.Macrofaunal abundances showed different patterns with varying proximity from the disposal point in the two surveys.In May 2008,lower abundances were observed at0 m(53.89±46.82 ind.)than at 15 m(120±91.7 ind.)and 30 m(283.89±189.33 ind.)away from the disposal point.In January 2009,however,higher abundances were observed at 0 m(131.33±58.69 ind.)than at 30 m(100±24.44 ind.)and 15 m(84.78±58.39 ind.)away from the disposal point.Significant differences in macrofaunal assemblage structure were found with varying proximity from the discharge point in both surveys.The effect of proximity from the disposal point was confounded by changes in sedimentary composition between surveys,which contributed to explain differences in macrofaunal abundances and assemblage structure with varying proximity from the discharge point.As a result,confounding drivers of macrofaunal assemblage structure,here,changes in sediment composition,accounted for changes in macrofaunal abundances and assemblage structure with varying proximity from a combined disposal point of brine and sewage. 相似文献