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21.
张萍 《攀登》2007,26(3):161-163
电视事业是党和人民的喉舌,我国电视事业的发展要坚持为社会主义和为人民服务的方向,坚持以群众性为重要特征,始终保持电视事业与人民群众的血肉联系。  相似文献   
22.
Expanded border enforcement has made unauthorised migration to the US more risky, costly, and prone to failure. Research on the material consequences of border enforcement for migrant‐sending households in Central America reveals that the economic hardships enforcement exacts on migrants at times diminishes enforcement's desired deterrent power. Heightened risks have driven up the cost of migration and pushed many to fund their trips through loans. Consequently, migrant detention, deportation, or death can result in poverty and privation for indebted households and the seizure of loan collateral, typically homes and land, in turn prompting crises in household reproduction. With a US wage the most viable means to ameliorate economic hardships, enforcement outcomes push some to return migration. Our findings suggest that US border enforcement efforts at times perpetuate the very unauthorised migration they seek to impede, while also helping to reproduce the border itself by deepening the marginalisation that drives migration decisions.  相似文献   
23.
The stable carbon and nitrogen isotope ratios of collagen of seven bones from each of three rabbits raised on a monotonous diet, and of two bones from each of eight female and seven male mink raised on another monotonous diet, were determined. The ranges of δ13C values and δ15N values were 0·5‰ and 0·6‰ for the rabbit bones and 1·0‰ and 1·4‰ for the mink bones. Uncertainties in the δ13C and δ15N values for prehistoric human diets estimated from the isotopic composition of collagen from the small numbers of bones which are typically available for analysis, and thus likely to be of the order of ±1‰.  相似文献   
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This study conducted petrographic and geochemical analyses of chert artifacts from the Late Middle Paleolithic, the Initial Upper Paleolithic, the Early Upper Paleolithic, and the Epi-Paleolithic assemblages in the Jebel Qalkha area, southern Jordan, to examine their correlations with the visual attributes and diachronic variability. The results revealed two different aspects of the petrographic and geochemical signatures. The first aspect showed some correlations with the visual chert types that were characterized by the abundance/preservation of fossils, the enrichment of several elements (i.e., Ca, Sr, and Ba), and the quartz crystallite size. The second aspect of geochemical signatures, such as Fe, Mn, Ni, Cr, and Co, showed no correlation with the visual types but was correlated with the chrono-cultural groups. Given the chert occurrences and variability in and around the study area, the first aspect of the chert variability likely represents the variations of different chert outcrops as well as the internal variations within the same sources. Whether the second aspect represents chrono-cultural changes in the use of chert sources needs to be clarified in future by our ongoing examination of geological chert samples in the study area.  相似文献   
26.
Written sources and iconographic evidence suggest that honey and beehive products, used in culinary, medicinal, and technological functions since pre-Neolithic times, were likely known and used in Phoenician and Punic Sardinia. The role of these resources is nonetheless poorly understood because no direct evidence survives on a macroscopic level. Significant advances in the knowledge about beeswax and beehive products processing in the past have been offered in recent decades by organic residue analyses (ORA), an approach that enables the characterisation of surviving chemical compounds or suites of compounds that provide information relating to human activity in the past. The relatively recalcitrant nature of lipid compounds comprising beeswax means that this commodity is among the products that can be unambiguously identified through ORA. Here we present and discuss the results of analyses undertaken on 368 pottery sherds from Phoenician and Punic Sardinia (eighth to third century BCE). These analyses offer direct evidence for the presence of beehive products on the island, suggesting the use of honey for culinary purposes in pots, and possibly connecting one specific vessel category with beeswax decanting during beekeeping and honey production processes. Our results also now clearly illustrate the widespread use of beehive products in pre-Roman Sardinia.  相似文献   
27.
漆灰的修复是漆器文物修复工作的重要组成部分。为揭示故宫博物院旧藏漆器3种典型漆灰的材料构成及特点,以及为漆器修复工作提供科技支持,研究结合X射线荧光光谱、微区X射线衍射、红外光谱、纤维显微镜观测、热裂解-气相色谱/质谱联用等技术,综合分析了3种典型漆灰所含无机及有机原材料。研究结果表明:明代古梅花蕉叶式琴漆灰所用无机材料是动物角灰或骨灰及少量黏土,胶结材料则由中国大漆及少量植物油组成;清代黑漆描金大宝座漆灰的无机材料为含有方解石的黏土,胶结材料为熟桐油、猪血的混合物,此外,样品中还含有麻类纤维,为宝座木胎与漆灰层之间所裱麻布,宝座漆灰不但能提供平整髹漆表面,而且还对麻布有加固定型作用;清代黑漆地填金字张廷玉书圣训天伦对联漆灰的无机材料为黏土,胶结材料则为熟桐油、猪血的混合物。研究所用分析方法体系可实现漆灰原材料,特别是有机胶结材料的准确识别。3种典型漆灰的选材特点与中国古代漆器,特别是明清时期家具、器物制作用料传统相吻合,研究结果可直接应用于漆器文物修复方案的制定。  相似文献   
28.
Little is known about the Battle of Good Friday in Uppsala. The historical records are scarce and of limited extent. Moreover, the more spectacular event of the Stockholm Bloodbath has drawn most of the attention from both the contemporary public and later historians. This is why the discovery of a mass grave in the steep slope of Uppsala Castle in 2001 has provoked much interest. An analysis of the osseous material showed that the remains of at least 60 male individuals, mostly between 25–34 years of age, were buried in the excavated area. The demographic profile is largely similar to other European war‐related skeletal assemblages of the same era. Sharp force trauma was exhibited primarily on the skulls, with no obvious dominance to either side. The trauma distribution pattern suggests that the battle was not fought face‐to‐face. Blade wounds concentrated in specific regions imply a standardised technique when delivering the blows. The combination of commingled bones and articulated elements suggests that the individuals were in different stages of skeletonisation when buried. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
29.
While scholars have made great strides in formulating theories and measuring public attention, “most important problem” and media‐based indicators are less than ideal measures. In order to address this shortcoming, this article borrows from health‐care epidemiology to measure public attention based on Internet search trends. In doing so, it reviews the innovative ways in which scientists have used search activity to track the spread of infectious disease, discusses the ease and flexibility with which search data can be gathered, and then subjects a Google‐based search measure to a series of validity tests. In particular, the analysis subjects the proposed measure to a battery of visual and statistical tests for convergent validity by comparing it with the most commonly used media‐based measure of public attention—issue coverage in the New York Times. Across a range of policy issues (health care, global warming, and terrorism), the proposed measure demonstrates convergent validity. The article concludes by posing a series of important questions that the new measure will allow researchers to address.  相似文献   
30.
There has been an impressive stride in the research on policy feedback effects on mass publics over recent years. However, we lack systematic evidence on how large such policy feedback effects are in the literature. This article provides a review of 65 published studies and quantifies the findings and key themes in the policy feedback literature. The results show a great degree of heterogeneity in the domains and outcomes being studied and in the effects of policies on the public. In line with the findings from narrative reviews, feedback effects are greater for outcomes related to political participation and engagement. Last, the review sheds light on important theoretical and methodological limitations to be addressed in future research.  相似文献   
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