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 系统梳理巴基斯坦1947-2017年的全国性教育政策文本,发现巴基斯坦政府颁布的9份教育政策文件均涉及科技教育内容。结合政局和一般社会发展状况的分析发现,巴基斯坦科技教育政策及其实施经历了4个阶段的变化。1947-1971年,受国家整体知识发展水平限制,新生国家面临各种国内外政治经济等迫切问题,科技教育政策无法得到完全实施。1972-1998年,巴基斯坦国内外政治局势变换,教育政策未得到持续、稳定的有效实施,科技教育发展缓慢。1998年以来,政治环境得到改善,科技教育真正开始得到重视并快速发展。目前巴基斯坦科技教育尚处于精英教育和实用教育阶段,投入短缺和无专门管理机构,是掣肘其科技教育规划落实的两大因素。  相似文献   
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以俄罗斯学者巴赫金的对话理论引入到教学语言研究中所形成的教学语言改革为切入点,从对话式课堂语言特性的理论基础、对话式课堂语言的特性、对话式课堂语言的语用分析等方面来探索研究对话理论引入教学语言研究的本土化、实践化的过程。  相似文献   
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Records of 19 species and one subspecies of water beetles of four families: Gyrinidae (two species), Dytiscidae (seven species), Hydrophilidae (10 species), and Spercheidae (one subspecies) from Pakistan are listed, based on collected material. Four genera and 10 species are recorded from Pakistan for the first time. The newly recorded genera are: Patrus, Helochares, Sternolophus and Coelostoma. The newly recorded species are: Dineutus spinosus (Fabricius, 1781), Patrus haemorrhous (Régimbart, 1891), Copelatus freudei Guignot, 1955, Copelatus sp1, Copelatus sp2, Enochrus ater (Kuwert, 1888), Helochares anchoralis Sharp, 1890, Sternolophus rufipes (Fabricius, 1792), Paracymus aeneus (Germar, 1824) and Coelostoma stultum (Walker, 1858). Zoogeographic affinities of the recorded species are discussed. According to their current distribution, the 18 species known from Pakistan can be classified into five zoogeographical categories.  相似文献   
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Summary

A new genus and species of nematobothriine didymozoid, Halvorsenius exilis, is described. These worms occur unpaired and unencysted in the connective tissue of the mackerel Scomber scombrus, especially in the pericardium, the ‘throat’ region, the orbits and the region of the kidneys. Halvorsenius belongs to a group of genera which possess three uterine loops and two testes, but can be distinguished by the atrophy of the gut and other features. Live worms occur only in young mackerel, although aggregations of eggs are found in older fish. It appears that the eggs are retained in utero until the death of the worm and that there is no obvious mechanism for voiding the eggs from the fish other than through the death of this host.  相似文献   
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南亚地区具有重要的战略地位,美国与印度和巴基斯坦的关系充分反映了美国的南亚战略.美国与印巴两国关系的变化自印度独立以来经历了美巴轴心、印巴均衡、扬印抑巴、重巴顾印等四个不同阶段.通过对这四个阶段的分析,可以得出这样一个结论:美国的南亚政策是出于维护其全球战略利益的考虑,而远非维护地区和平.  相似文献   
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《Journal of Natural History》2012,46(41-42):2671-2689
The ground beetle taxon Kashmirobroscus gen. nov. and two species Kashmirobroscus mirabilis sp. nov. and Kashmirobroscus ortrudae sp. nov. are described from the Northwest Himalaya of Pakistan. Diagnostic characters of both new species are figured and their distributional areas are mapped. Several features of the new genus are discussed to work out its systematic position within Broscini. As a result, Kashmirobroscus is proposed as a sister taxon of the East Asian genus Eobroscus Kryzhanovskij, 1951, of the subtribe Broscina. In addition, new data relating to systematics and distribution of all the known species of the genus Eobroscus are provided. The taxon Orobroscus Morita, 1990 is proposed as a junior synonym of Eobroscus Kryzhanovskij, 1951, and Eobroscus uenoi Morita, 1995 is proposed as a junior synonym of Eobroscus bhutanensis Morvan, 1982, a macropterous species with a wide distribution in the eastern parts of High Asia. http://www.zoobank.org/urn:lsid:zoobank.org:pub:1775013D-FE87-41CA-87AF-D730E809331B  相似文献   
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The photocatalytic activities of g-C_3N_4 can be significantly improved by increasing life time of the photogenerated charges. Here, in this work we introduced TiO_2 as proper energy platform to accept the photogenerated electrons from g-C_3N_4 during photocatalysis. The nanophotocatalysts formed from the combination of a suitable amount of TiO_2 nanoparticles and g-C_3N_4 nanosheets showed 8.75 and 4.22% enhancement in photocatalytic activities for CO_2 reduction and 2-chlorophenol(2-CP) degradation under visible light illumination as compared to bare g-C_3N_4. Based on the surface photovoltage spectra, photoluminescence spectra and examination of formed hydroxyl radicals, it was confirmed that these enhanced photoactivities were attributed to the much-improved charge separation via the electron transfer from g-C_3N_4 to TiO_2. From trapping experiments,it was found that hydroxyl radicals were the major species involved in the photocatalytic degradation of 2-CP.This study is helpful to synthesize efficient photocatalysts to cope with energy and environmental issues.  相似文献   
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A list of species of the family Caliscelidae Amyot et Serville known from India with data on distribution and sources for identification and a key to genera are given. The genus Bolbonaso Emeljanov, 2007 is revised. A new species, Bolbonaso chandri sp. nov., is described from Eastern India (Assam and Meghalaya States). Bolbonaso tapirifacies (Parshad, 1981) is redescribed and recorded for the first time from Southern India (Karnataka State). The lectotype is designated for Chirodisca eximia (Stål, 1859) which is recorded for the first time from Pakistan. New faunistic data in Nepal are listed for Delhina eurybrachydoides Distant, 1912.  相似文献   
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