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81.
Following are a review and a discussion of V. A. nuchin's controversial book Teoreticheskiye problemy geografii (Theoretical Problems of Geography), Moscow: Geographical Publishing House, 1960, 264 pp. The table of contents of this book was translated in Soviet Geography, March 1961, p. 88.  相似文献   
82.
The authors urge a zonal specialization of agriculture within the countries of the Socialist camp, particularly the CEMA grouping. Bulgaria, which supplies tobacco, grapes, early vegetables, and fruits to other countries, in cited as an example. Geographers are urged to work out such a specialization scheme based on a complex of factors, including the physical-geographic base, manpower resources, the present state of agriculture, and the traditional working habits of the population.  相似文献   
83.
84.
Pierre Marie was a prominent member of the French neurological world of the early twentieth century. Having been trained by the celebrated physician, J-M Charcot, Marie remained influenced by his teacher throughout his career. Because of this influence, his career can be logically divided into three phases: first, the early years under the direct mentorship of Charcot (1878-1893); secondly, the aftermath of Charcot’s death when Marie left his teacher’s institution, the Salpêtrière hospital and established himself at the Bicêtre hospital in southern Paris (1893-1918); and finally, Marie’s return to the Salpêtrière to assume the original Charcot chaired professorship, albeit as an aged man (1918-1925). This essay examines Marie’s career with an emphasis on documentation of the combined attributes of a gifted intellect as well as a heated emotionality. In the context of his time, these elements prompted Marie to enter into controversies and medico-political battles that advanced neurological knowledge, but likely disadvantaged him in his career successes.  相似文献   
85.
The article examines the prospects of using runoff characteristics and changes in runoff composition as a basis for predicting environmental modification. The technique is employed to assess changes in the circulation of matter that are taking place in the drainage basin of the Aral Sea as a result of the intensification of irrigation. Overall runoff, including its liquid, solid (suspended sediment) and chemical phases, is analyzed in connection with a shift in the deposition of material from the Aral Sea to the irrigated plains.  相似文献   
86.
Continuing net out-migration from Siberia produces a manpower supply problem that must be resolved if the regions's economic development is to be pursued. A high rate of labor turnover tends to raise the costs of industrial development and to lower the skill levels of workers as skilled labor leaving Siberian cities for other parts of the USSR is replaced by untrained manpower from the Siberian countryside. Wage differentials in effect in Siberia have been effective in attracting manpower from the Western regions for short periods of time, but have not stimulated permanent settlement. In the view of the authors, new arrivals can be induced to settle down in Siberia only if the adverse impact of the Siberian environment can be compensated by a level of housing and services that is superior to those available elsewhere in the Soviet Union. The significant element is housing, which should receive particular attention in future investment programs. Northern development within Siberia poses the additional problem of physical acclimatization.  相似文献   
87.
This object-specific case study focuses on cupreous artifacts excavated from the Great Temple complex of Petra, Jordan to demonstrate how the use of compositional X-ray analyses alongside two experimental applications (ImageJ software and nanoindentation) have the potential to generate different and otherwise unobtainable information about archaeological metals. The study highlights the value of using multiple techniques as a means of resolving the ambiguities that tend to arise from interpretations of single-sited measurements on objects and from single-instrumental analyses during studies of production processes and consequent material performance. Employing different techniques on multiple localities within a sample permits the gathering of precise information about the behavior of and interrelationships between variables that affect the objects’ fabrication and use, particularly composition, structure, and hardness properties. The resulting data are interpreted in association with contextual archaeological information from Petra to consider the use-life and potential significance of these objects.  相似文献   
88.
Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.  相似文献   
89.
Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.  相似文献   
90.
This paper explains, with the example of a Roman object (the ‘Mars from Oberweningen’, Switzerland), why neutrons can be used preferentially for the non‐destructive analysis of metallic objects of relatively large size. This method is superior to the conventional X‐ray tomography method due to the higher penetration ability in metals such as copper, tin and even lead. With this method, differing materials can also easily be differentiated. In this way, the inner and outer structures of objects can be observed with the help of tools based on mathematical algorithms. Slices at arbitrary positions and segmentation of different material clusters aid the understanding of manufacturing processes and can describe the present preservation status. This helps in selecting optimal and additional conservation measures in museums for further preservation. Beside the qualitative overview on structure and inner properties of the objects, quantitative information can be derived about material content and composition. This method and the subsequently needed facilities for this method are available at PSI for similar studies on demand.  相似文献   
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