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121.
This article analyzes China’s attempts to participate in and use the negotiations about reforming the international opium control system in the interwar period. China had a contentious relationship with the international opium control system from its creation in the International Opium Convention of 1912 through the League of Nations opium control system of the 1920s and 1930s. The Chinese government wanted to gain acceptance for China as a modern state no longer in need of tutelage from the international community. They also wanted to portray the Chinese people as a modern race as a way of undermining colonial opium monopolies, which made a disproportionate amount of their profits from sales to Overseas Chinese. While they were not fully successful in either of these efforts, China did manage to win some support, drawing the United States into closer agreement with China’s positions. Engagement with the international system also had a considerable impact on China’s domestic opium politics and its broader diplomatic relationship with the major powers.  相似文献   
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Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is applied to the study of four samples of opaque glass of Late Bronze Age date. The technique is uniquely capable of identifying compositional heterogeneity at a sub-micron resolution within the crystalline opacifiers dispersed through homogeneous glass matrices. It is shown that this provides crucial information on the possible raw ingredients of the opacifying inclusions used, and has the potential for highlighting regional variations in the production technology involved in creating different colours of opaque glass.  相似文献   
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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   
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ABSTRACT The twenty‐first century will be one of intensified urbanization, on a scale never before experienced. How do urban systems and individual cities change and develop? The social sciences have many different approaches to analyzing the economic, social, and spatial dimensions of urban change. We inventory some of these approaches and their implications for public policy toward cities, urban change, and economic development.  相似文献   
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Zooarchaeologists have often employed studies of bone fracture morphology as a means of understanding past human cultural activity, and various methodological approaches have been developed for analyzing archaeological broken bone assemblages. It is widely understood that bones degrade over time, however, few studies have attempted to define and quantify the rate at which bones degrade and fracture morphologies change. This study examines degradation in frozen bones (−20 °C) and bones exposed to hot (40 °C) dry conditions. These two simulated environmental conditions represent extreme real-world climates, and allow for an actualistic understanding of the rates of degradation that bones experience in nature. When frozen, bones degrade slowly but significantly, and demonstrate measurable differences in samples frozen for 1, 10, 20, 40, and 60 weeks. In hot, dry conditions, bones degrade very quickly, and demonstrate measurable differences after 1, 3, 7, 14, and 21 days. These data allow for a more detailed understanding of the relationship between the cultural and natural processes that result in bone fracture, and the time period during which bones can be expected to maintain fresh fracture characteristics. This research also has implications for understanding human subsistence and survival strategies and for interpreting the archaeological record.  相似文献   
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