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81.
刘勇  王莹  高建华 《人文地理》2011,26(3):71-75
文章在分析河南省城市化发展阶段性特征的基础上,对城市化和产业结构之间的变动关系进行了对比分析、相关分析和回归分析,并用Arcgis9.3以"产业结构演变城市化响应系数"为指标绘制地图,反映了河南省城市化与产业结构之间作用强弱的空间差异,分析表明,河南省城市化与产业结构存在严重偏差,原因在于城市化与产业结构的非协调发展和产业结构与就业结构的不合理发展;河南省的产业结构演变城市化响应呈现"西高东低"、"北高南低"的地理分布特征。最后针对问题提出了对策。  相似文献   
82.
Until now, the oldest known human hair was from a 9000-year-old South American mummy. Here we report fossil hairs of probable human origin that exceed that age by about 200,000 years. The hairs have been discovered in a brown hyaena (Parahyaena brunnea) coprolite from Gladysvale cave in South Africa. The coprolite is part of a hyaena latrine preserved in calcified cave sediment dated between 195,000 and 257,000 years ago. This find supports the hypothesis that hyaenas accumulated some of the early hominin remains found in cave sites, and provides a new source of information on Pleistocene mammals in the Sterkfontein Valley.  相似文献   
83.
Stable carbon- and nitrogen-isotope ratios were measured for segments along the shafts of hair from eight individuals from the site of Pacatnamu, located in the Jequetepeque Valley on the north coast of Peru. All are from known grave contexts dating from Moche (ca. 450–750 A.D.) to Lambayeque periods (ca. 900–1100 A.D.). The mean δ13C and δ15N values of hair segments from individuals are comparable to those of bone, and demonstrate increased consumption of marine resources in the Lambayeque times relative to the Moche period.  相似文献   
84.
We conducted a paleo-parasitological study on soil samples from the ancient moat ruins of Weolseong palace, of the Silla Dynasty (BC 57–AD 935) of Korea. Based on the cultural remains found in the mud-soil layer, the layer was precipitated onto the floor of a moat between the 5th and 8th centuries AD. We found Trichuris trichiura eggs only in that mud-soil layer, whereas no parasite eggs were identified in the other archaeological strata of the ruins. As T. trichiura eggs are shed only in human feces, we speculated that palace toilet contents were continually drained into the moat; therefore, at a certain point in time after construction, the moat finally became a ditch around the palace. Structures in the stone embankments of the moat, possibly designed to make the water flow continuously in one direction, might reflect the Silla people's efforts to alleviate the ever-increasing problems inherent in a moat.  相似文献   
85.
甘肃省永登县连城鲁土司属寺壁画的科学分析和时代研究   总被引:2,自引:0,他引:2  
本项研究主要是运用光学显微镜、扫描电子显微镜和共聚焦显微激光拉曼光谱技术,分析了甘肃永登连城鲁土司属寺中的妙因寺、感恩寺和雷坛中的部分壁画。分析结果表明感恩寺和雷坛壁画基本保持了明代最初的绘制风格和内容。其中感恩寺主要壁画的绘画颜料和工艺特点鲜明,表明绘制该壁画的画工不同于绘制鲁土司属寺其他壁画的工匠;妙因寺万岁殿壁画存在后期改动和重绘的情况,其中万岁殿外回廊壁画主要部分的最初绘制时间要早于万岁殿大殿内壁画的最后绘制时间;而妙因寺塔尔殿壁画则绘制于19世纪后期。  相似文献   
86.
Research on the neurobiology and pharmacotherapy of attention-deficit/hyperactivity disorder (ADHD) has grown exponentially since 1980. A reasonable question is whether this research has improved our understanding and treatment of ADHD. This article describes relevant developments that took place roughly between 1900 and 1970. During this time, the efficacy of stimulant therapy for the disorder was established and the symptoms of ADHD were linked to many possible nervous system disorders including in the brain-stem, reticular formation, diencephalon, basal ganglia, frontal lobes, and cortex. In 1970, the catecholamine hypothesis of ADHD was proposed. It is concluded that early theories about the neurobiologic basis of ADHD anticipated core ideas of modern theory.  相似文献   
87.
Fezzeh Khanom (c. 1835–82), an African woman, was a slave of Sayyed ‘Ali-Mohammad of Shiraz, the Bab. Information about her life can be recovered from various pious Baha'i histories. She was honored, and even venerated by Babis, though she remained subordinate and invisible. The paper makes the encouraging discovery that a history of African slavery in Iran is possible, even at the level of individual biographies. Scholars estimate that between one and two million slaves were exported from Africa to the Indian Ocean trade in the nineteenth century, most to Iranian ports. Some two-thirds of African slaves brought to Iran were women intended as household servants and concubines. An examination of Fezzeh Khanom's life can begin to fill the gaps in our knowledge of enslaved women in Iran. The paper discusses African influences on Iranian culture, especially in wealthy households and in the royal court. The limited value of Western legal distinctions between slavery and freedom when applied to the Muslim world is noted.  相似文献   
88.
This study explores how a scientist's location in science‐based policy networks can affect her policy‐oriented behaviors. In particular, we hypothesize that those scientists who fill structural holes in their networks will be more likely than others to engage in policy‐oriented behaviors. The network data are defined by scientists' coauthorship on policy documents regarding climate change in the Great Lakes. We employ a two‐mode network analysis to identify clusters of scientists who coauthored similar documents, and relative to those clusters, we identify those who fill structural holes by bridging between clusters. We find that those scientists who bridged between clusters were more likely to engage in policy‐oriented behaviors of policy advocacy and advising than were others in the network. This is an example of a link between network location and policy‐oriented behavior indicative of the broader phenomenon of how individuals exert agency, given structural constraints.  相似文献   
89.
Recent developments in the biopharmaceutical industry in Taiwan, South Korea and China bear witness to the transformation of these states in nurturing an innovation‐based industry. This article argues that the segmentation of the value chain of the biopharmaceutical industry has provided industrializing countries with a window of opportunity. These East Asian states have modified their former catching‐up approaches by establishing a more effective institutional platform that can attract knowledge‐creation players to the industry. Through case studies, the authors show that the Taiwan state's promotion of the biopharmaceutical industry has been based on an incremental approach; existing state policies have been modified to cope with the demands of the industry, which has resulted in the continuation of its SME‐based industrial structure. The methods of the Korean state have been more radical, in that the policies that previously favoured the chaebols have gradually been reoriented toward the promotion of smaller, science‐based firms that now co‐exist alongside the chaebols. Finally, the Chinese state and local governments have sought to promote this innovation‐based industry by building biotech parks. This approach has resulted in a boom in new science firms, which have become increasingly isolated from the flourishing domestic SOE‐led market.  相似文献   
90.
大富裕沟村位于内蒙古赤峰市西南部山区,20世纪40年代以前,这里植被茂密,生态环境较好。六七十年代,生态环境遭到严重破坏,村民的生产生活陷入困境。90年代以后,被破坏的生态环境得以逆转。该村生态环境由好变坏的原因:其一是人口增加超过了生态环境的承受极限,其二是传统的农牧业生产方式和相对应的生活方式在人口达到环境承受的极限后成为破坏环境的人类活动模式。该村生态环境由坏变好的原因:其一是计划生育政策和城镇化引发的人口大幅度减少,从而减轻了生态环境的压力;其二是现代化的生产和生活方式大大减少了人类活动对资源的索取,其三得益于70年代开始的对生态环境的不遗余力的保护政策和措施。  相似文献   
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