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1.
Heat-related mortality remains a public health challenge in the United States. The objective of this study was to determine the temporal consistency of high-risk zones for heat-related mortality using historical georeferenced mortality data from seven US cities. A generalized additive model was used to identify city-specific threshold temperatures associated with increased mortality, and then the mortality rate on threshold-exceeding days was calculated for each postal code comprising each study city. This process was iterated by withholding subsets of data from the model and assessing predictability via cross-validation. In all cities, the average mortality rate in postal codes targeted for intervention by the statistical model was higher than that in non-targeted areas. Targeted areas for interventions in the study data accounted for 50 % of excess heat-related deaths despite only accounting for 25 % of total mortality. Focusing intervention measures at certain geographical zones within urban areas could be an effective means of combating heat-related mortality because there is temporal consistency in places where the death rate is most sensitive to heat.  相似文献   

2.
This study examines the seasonal variability in the heat mortality relationship across 29 US metropolitan areas from 1975 to 2004 to discern the seasonal cycle of the health risk from anomalously high temperatures (relative to the time of season). Mortality data for the 30-year period are standardized to account for population trends and overall seasonal and interannual variability. On days when a city experienced an “oppressive” air mass, mean anomalous mortality was calculated. Results show that while the greatest overall health impact is found mid-summer in many locations due to the peak frequency of hot weather occurring at this time, the relative increase in acute mortality on oppressive air mass days is actually just as large in spring as it is in summer, and in some cases is larger. Late summer and autumn vulnerability to anomalously warm or hot days is much less significant than spring days in all areas except along the Pacific coast. Results show significant spatial variability, with the most consistent results across the more ‘traditionally’ heat vulnerable areas of the Midwestern and northeastern US, along with the Pacific Coast. Elsewhere, the seasonal cycle of the correlation between anomalously high temperatures and human health is more ambiguous.  相似文献   

3.
极地钻探是获取极地冰层或冰下环境样品和在极地冰层或冰下布放科学观测仪器的最直接方法,是开展极地科学研究的必要技术手段。美国是开展极地钻探较早的国家之一,也是极地钻探强国。相比美国,我国极地钻探技术尚处于起步阶段。本文以《美国冰钻委员会长期科学规划2021-2031》为基础,结合其官方网站和相关文献资料,梳理了美国极地钻探科学目标和极地钻探技术现状,并简要介绍了过去10年美国极地钻探的现场工作情况及其在未来3年的工作计划,以期为我国极地钻探发展提供参考。  相似文献   

4.
刘细元  王道英  游玮 《华东地质》2007,28(4):298-305
该文简单介绍了江西省主要城市的自然地理、区域环境地质背景及社会经济概况;阐述了对城市建设用地地质环境质量评价目的,进而采用敏感因子-模糊综合评价方法,对全省11个主要城市的建设用地地质环境质量进行了评价.江西省各主要城市的城市建设用地地质环境质量总体较好,其中地质环境质量80%以上为好和较好的有抚州市和九江市,地质环境质量50%~72%为好和较好的有吉安市、新余市、南昌市和上饶市,地质环境质量30%~40%为好和较好的有鹰潭市和宜春市,地质环境质量为好和较好的在30%以下的有萍乡市、赣州市和景德镇市.  相似文献   

5.
A very interesting and informative paper on widespread occurrence of a thermal hydrosphere. Geothermal power uses are discussed. Distribution of heated waters, some up to 150° C is discussed in considerable detail, especially with reference to possible power utilization of the geothermal energy. Seven hydrothermal regions of the U.S.S.R. are discussed and delineated. Chemical quality of waters is referred to. There is a summary listing of locations in the U.S.S.R. where thermal waters could be utilized for generation of electric power. — B. N. Cooper.  相似文献   

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7.
A major field of research since the 1920s has been methods and theories of economic regionalization. The territorial-production complex is now recognized as a key developmental tool within the framework of economic-planning regions. Recently, there has been a more marked growth of study into problems of natural-resource development, social progress and change in the U.S.S.R. as well as into the spatial structure of other nations, particularly other socialist countries and non-socialist developing countries.  相似文献   

8.
The deinocephalian pelvic girdle, of general pelycosaurian structure, is useful in systematic diagnosis. In primitive Russian deinocephalians, two contrasting pelvic patterns are recognized, one light, thin-walled, narrow, and of V-shaped cross-section, and the other massive, thick-walled, wide, and of U-shaped cross-section. The former is characteristic of two families of lightly- built, mobile land carnivores, the Eotitanosuchidae and the Brithopodidae. The Eotitanosuchidae are more primitive and pelycosaur-like, while the Brithopodidae show more variation, and specializations of large size, shallower acetabulum (related to mobility?), and re-enforcement of a weak pubic symphysis by additional processes. The massive type of pelvis characterizes large, heavily built herbivorous animals of the family Estemmenosuchidae. In general pelvic structure, the Estemmenosuchidae resemble the South African anteosaurs and tapinocephalians and the Russian tapinocephalians. In detail, however, they show a more primitive stage of evolution, overlaid by characteristic specializations which relate them more closely to the advanced Russian forms than to those of South Africa. Three new genera are erected, Biarmosaurus, fam. Eotitanosuchidae; Chthomaloporus, fam. Brithopodidae; and Molybdopygus, fam. Estemmenosuchidae. One specimen formerly referred to Deuterosaurus Yefremov 1954, and five formerly included in the type of Brithopus Yefremov 1954 are referred to Molybdopygus. The more primitive deinocephalians are from Yezhovo in the Ocher District, Perm Province, while more advanced forms are from Isheyevo, in Tataria, where-therocephalians and other South African elements are also found. It is therefore concluded that the Ochersk beds are older than those of Isheyevo and must be dated to zone I of Yefremov's system. — N. Hotton III.  相似文献   

9.
A seismic hazard evaluation for three dams in the Rocky Mountains of northern Colorado is based on a study of the historical seismicity. To model earthquake occurrence as a random process utilizing a maximum likelihood method, the catalog must exhibit random space-time characteristics. This was achieved using a declustering procedure and correction for completeness of recording. On the basis of the resulting a- and b-values, probabilistic epicentral distances for a 2 × 10–5 annual probability were calculated. For a random earthquake of magnitude M L 6.0–6.5, this distance is 15 km. Suggested ground motion parameters were estimated using a probabilistic seismic hazard analysis. Critical peak horizontal accelerations at the dams are 0.22g if median values are assumed and 0.39g if variable attenuation and seismicity rates are taken into account. For structural analysis of the dams, synthetic acceleration time series were calculated to match the empirical response spectra. In addition, existing horizontal strong motion records from two Mammoth Lakes, California earthquakes were selected and scaled to fit the target horizontal acceleration response spectra.  相似文献   

10.
Soviet geologists consider the Precambrian to be divided into two groups — Archaean and Proterozoic; but such a division is unsatisfactory. A major unconformity separates Proterozoic volcanic and sedimentary formations from an underlying sequence that contains two supergroups of supercrustal formations. The oldest of these is unanimously considered to be Archaean. Rocks of that supergroup play an essential part in the composition of the Baltic, Ukrainian, Aldan and Anabar Shields and of the ancient fold belts of the East-European and Siberian platforms.Distinctive features in the composition, tectonic structure, metamorphism and metallogeny of Archaean complexes lead to the conclusion that they were formed in specifically mobile areas, different from geosynclinal areas.The other supergroup of high-grade metamorphic rocks has no clear place in the accepted two-fold stratigraphic scheme of the Precambrian, and it is considered sometimes to be Archaean and sometimes to be Early Proterozoic. We propose restoring the forgotten name “Eozoic” for that supergroup. Eozoic complexes are characterized by peculiarities of composition and inner structure, which signify changes in the tectonic regime of the earth at the lower and upper boundaries of the Eozoic Supergroup. These peculiarities give grounds for distinguishing the Eozoic Supergroup as an independent stratigraphic division.The Stanovoy Complex of the southern part of the Aldan Shield is a stratotype for the Eozoic Supergroup. Many well-known stratigraphic subdivisions of the Siberian Platform (e.g., the Eniseiskaya, the Birusinskaya series and others), the Taratash Complex of the Urals, the Goranskaya and Shahdarinskaya series of the South-West Pamir, the Tikitch complex and Aulskaya series of the Ukrainian Shield, and in part the Belomorsky Complex of the Baltic Shield, as well as some others, are also Eozoic.The Eozoic complexes are characterized by the following specific features: only some supercrustal formations are typical for them; the small number of rock types which have a total thickness about 5–6 km; relatively monotonous mineral composition of the rocks; variable quantitative ratios of rocks; absence of contrasting marker beds; regional metamorphism and ultrametamorphism in the amphibolite facies; wide development of ultrametamorphic granitoids and migmatites; distinct tectonic differentiations of the basin of sedimentation.Dates determined by isotopic analyses, which mostly reflect the metamorphism of the deposits, fall predominantly in the range 2600–3100 Ma.  相似文献   

11.
A study has been completed of the baseline concentrations of Mo in bottom sediments of the major rivers in Colorado. Three hundred and seventy-nine samples were taken from 14 rivers in the state. The geometric means for the concentration of Mo in the minus 80-mesh fraction of the sediment were found to vary from 1.2 to 14.0 ppm. The geometric mean for each river can be logically grouped according to the presence or absence of mineralization upstream in the drainage basin. This grouping results in three categories according to the extent and type of mineralization in the drainage basin. A grouping on the basis of mineralization accounts for 15% of the total variation in the concentration of Mo in the sediment, suggesting that Mo-rich sediment is transported downstream from mineralized areas and exerts a major influence on the baseline concentration. Multiple samples are required to characterize each river because the withinstream component of variance comprises 54% of the total variance.Bottom sediment (minus 80 mesh) is a sensitive indicator of Mo mineralization; values of molybdenum as low as 2 ppm were considered anomalous for several rivers. A precise analytical procedure permits detection of concentrations of Mo in sediment approximately 2 ppm below the detection limit of the usual potassium pyrosulfate-thiocyanate procedure.  相似文献   

12.
Analysis of blocks and linear sutures in the base of the Russian Platform shows significant variations in their tectonic activities in different stages of the platformal evolution. --AGI Staff.  相似文献   

13.
Mercury inhomogeneity was found between bottles of the same standard for each of the six U.S.G.S. rock standards tested. Variations between bottles amounted to at least a factor of 2 for four of the six standards. Caution is suggested when using these standards as mercury accuracy checks and as estimators of mercury geochemical abundances or cycles.  相似文献   

14.
Areas of the U.S. Gulf Coast, both onshore and offshore, are among the petroliferous regions of the United States. In offshore Louisiana and Texas, most oil and gas is associated with structurally controlled traps on the crest or flanks of domes created by the diapiric movement of salt. These structures can be detected and mapped by seismic techniques that directly indicate favorable prospective areas. The characteristics of seismically defined structures provide information in advance of drilling about the probable size of reservoirs contained within these structures. Simple statistical relationships can be determined between the size, shape, and other attributes of structures detected by seismic mapping and the presence and size of petroleum and natural gas reservoirs. Gulf Coast OCS lease tracts presently are evaluated by the U.S. government using a Monte Carlo simulation procedure adapted from reservoir analysis. Specification of the parameters of the Monte Carlo model are obtained subjectively in advance of drilling and thus are highly uncertain. Comparisons of predrill predictions with postdiscovery reservoir evaluations show very low correlations. In contrast, predrill predictions based on regressions between seismic structural properties and reservoir volumes show highly significant correlations. In addition, statistical analysis of seismic structure is much simpler than the Monte Carlo procedure, and can be applied rapidly and inexpensively. A statistical analysis of the “Pleistocene Trend” of offshore Louisiana and Texas, an area of about 3 million acres, yielded results that are sufficiently encouraging to suggest that similar evaluations be made of the remaining Gulf Coast OCS and of OCS regions off of other coasts of the United States.  相似文献   

15.
16.
A large number of specimens of Seymouriamorph amphibian, family Discosauriscidae, were collected from the south slopes of the Kuramanskiy Khrebet, Mt. Sarytaypan, 10 km northeast of the settlement of Adrasman, Tadzhik S.S.R. Deposits yielding the fossils consist of about 70 m of effusive sedimentary rocks, the top third being tuffs, tuff sandstones, and tuff breccias, and the remainder being alternating fine-grained sandstones, argillites, and siltstones, of gray, greenish, pink, and black colors. The beds overlie 800 m of tuff lavas and tuff breccias and are overlain by 200 m of-tuff breccias. Fossil leaves are abundant in the lower half of the beds in all lithologic types, but the vertebrates are confined to about 1 m of adjoining layers of fine-grained gray to pink sandstone, and almost black argillite. The fossils consist of complete impressions of skeletons, which will yield much anatomical information. Two genera are represented, the most abundant referrable to the Central European form Discosauriscus. The other is related to the European Leptoverpeton but may be new. These specimens permit correlation of the Sarytaypan deposits with Lower Permian' bedsgqn Czechoslovakia and Germany. Larval forms are by far the most abundant, but the presence of adults affords a reliable comparison of growth stages. New and detailed information of the development of the spinal column will also be forthcoming from further study of the growth stages. Presence of gills in the larvae reaffirms the persistence of an aquatic larval stage in the morphologically reptile-like Seymouriamorpha. — N. Hotton III.  相似文献   

17.
18.
《Earth》1973,9(3):314
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19.
A list of all Upper Cretaceous sea-lilies known from the U.S.S.R. is given. Their stratigraphic and geographic distributions are discussed. Three paleogeographic subprovinces, the south-eastern, the northern and the south-western, can be distinguished in the Mediterranean paleobiogeographic province of the U.S.S.R. based on the development and distribution of the Upper Cretaceous crinoids.  相似文献   

20.
On October 12, 1962, a joint session of the Presidium of the U.S.S.R. Academy of Sciences and the Collegium of the U.S.S.R. Ministry of Geology and Mineral Reserves adopted a resolution “On the present state of the geological sciences in the U.S.S.R. Academy of Sciences and the U. S. S. R. Ministry of Geology and Mineral Reserves and their prospects for the future.” Important contributions of Russian geologists are acknowledged, but attention is drawn to many shortcomings. Future goals of geological study and work are given in detail. Twenty-one lines of research to be concentrated on are given, covering all phases of geology, geophysics, and geochemistry. In discussing the failings of the geological profession in Russia, it is of interest to note the following comment: “Geological research in other countries is still insufficiently studied and applied, and we are not making adequate use of geologic information from abroad.” The list of the Russian geologists' shortcomings sounds vaguely familiar. —J. R. Hayes  相似文献   

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