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991.
The North‐Western Mediterranean witnessed a rapid expansion of farmers and their livestock during the Early Neolithic period. Depending on the region, cattle played a more or less important role in these communities; however how these animals were exploited for their milk is not clear. Here we investigate calf mortality to determine indirectly whether cattle dairying was practised by Early Neolithic stock herders. Age‐at‐death (AtD) frequencies for calves from two sites: Trasano (Italy, Impressa culture: 7–6th millennium BC) and La Draga (Spain, Cardial culture: 6th millennium BC) were estimated from dental eruption and development stages, and measurements of un‐fused post‐cranial material. Adult age classes are well represented in the dental AtD frequencies and were interpreted as the result of the slaughter of prime beef and retired lactating females. For calves aged less than 12 months, there was no statistical difference in the AtD frequencies based on dental and post‐cranial material indicating that the data is a good representation of the mortality patterns of calves, either natural or deliberate. At both sites there was a strong mortality peak at 3–6 months in all AtD profiles. At La Draga, this peak was clearly differentiated from a peak at 0–1 month, which can be interpreted neonatal mortality possible a consequence of the birthing season coinciding with the end of winter during more humid climatic conditions that at present. The deliberate slaughter peak around 3–6 months is discussed, and we propose that stock herders controlled the mortality of infant classes, possibly in response to variable external environment pressures while maintaining animal productivity. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
992.
In late life, the humeral impingement disorder becomes common due to degenerative changes in the rotator cuff which allow the proximal humerus to press against the acromion in elevation of the arm, so producing facets on the tip region of the subacromial surface and on the lateral margin of the greater tubercle of the humerus. To discover what changes occur prior to those described, 184 acromions below the age of 55 years were examined. During the 18–25 year period, the subacromial surface showed patterns of formation of surface trabeculae of new bone, some associated with union of the epiphysis or with remodelling as a response to the presence of the proximal humerus at a distance of 10–15 mm; others indicated a subacromial attachment of the coraco‐acromial ligament. As early as 30 years of age, flattening of the surface trabeculae of bone was noted in association with compression lipping of the outer margin of the greater tubercle of the humerus, the part that crosses closest to the subacromial surface during elevation of the arm. Although resembling changes found in the impingement disorder, in both populations by the age of 35 years the changes were too common to be so and were not associated with the erosive pitting of the upper surface of the tubercle regarded as the earliest bony criterion of degenerative change in the cuff. It is postulated that, in the normal shoulder joint, in raising the arm, pressure is exerted, perhaps transiently, in the subacromial bursa and adjacent soft tissues which induces the compressive changes described. Probably due to the physically arduous lifestyle of the islanders, these changes occurred earlier among them; so did (but later) cuff degeneration indicated by erosion of the humeral tubercle. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
993.
994.
本文立足长春市城郊关系的现状与发展,从郊区城市化特点与动力机制的分析入手,指出了长春市郊区城市化的适宜发展道路和时空演进过程,从而进一步演绎和揭示出了中国东部经济区域内陆中心城市郊区城市化的走向和一般趋势。  相似文献   
995.
While posterior lingual mandibular depressions (Stafne's defect) are often discussed in clinical reports, they are rarely the subject of anthropological research. This situation is paradoxical since osteologists and skeletal biologists are in a position to enhance understanding of the trait's aetiology by systematically recording the trait in recent and prehistoric skeletal collections. This report reviews anthropological studies of cortical defects of the mandible, recommends a protocol for recording observations in trait variation, and presents new data for the prevalence of Stafne's defect—lingual cortical defects of the mandibular corpus. Among the Guanches of Tenerife in the Canary Islands (Spain), the prevalence of lingual cortical defects is 3.32% (15/452), males are more frequently affected than females, and there is a tendency for individuals with antemortem tooth loss to display larger lesions than individuals without antemortem loss of teeth. Defects of the left side are somewhat more variable in position than defects located on the right. In comparative perspective, prevalence of lingual cortical defects among the Guanches is high, given the overall 1.07% prevalence reported for archaeological series (Finnegan & Marcsik,1980), but is similar to figures reported for the Avar period sample from Hungary 3.73%. Prospects for the use of lingual cortical defects as non‐metric traits of value in population distance studies remain uncertain since variation in trait expression may have a high environmental component. However, if human osteologists routinely include observations of lingual mandibular cortical defects in their analysis of skeletal collections, the data required to elucidate factors responsible for the trait's cultural, ecological, temporal and geographical patterning will more rapidly become established. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
996.
The purpose of the advocacy coalition framework is to explain policy change over time through an examination of the stability of advocacy coalitions within policy subsystems. Recently, scholars have confirmed that advocacy coalitions are held together by shared belief systems, specifically in distributive policy arenas. We contend that federal agencies, in distributive policy arenas, provide both the anchors and support systems for the development and maintenance of belief systems. This anchoring helps provide adequate resources, access to political institutions, ability to control administrative process, and/or the capacity to deliver public goods and services. We conducted an analysis of the policy changes that occurred during the implementation of the National Environmental Policy Act for the construction of the Bureau of Reclamation's Animas‐La Plata project. This is an example where administrators, through the management of information, were able to control the policy process. The analysis provides a needed replication of previous findings regarding policy change and offers new insights into how institutions are critical to subsystem stability over time.  相似文献   
997.
东部沿海地区农业结构变动特征及区域差异分析   总被引:8,自引:0,他引:8  
2005年东部沿海地区农、林、牧、渔产值比重是49.5:3.2:29.7:17.6,农业结构逐步得到优化。本文分析了农业结构系数与农民人均纯收入、人均GDP的关系,揭示了经济发达地区农业结构变动特征及其地域差异性,发现差异性主要表现在农业部门的变动趋势和农业结构的变化率;并根据比较优势理论,分析了地区间农业部门的比较优势,这也是未来区域农业结构优化布局的主要依据。  相似文献   
998.
It has long been recognised that cattle horn‐cores are sexually dimorphic, and many methods have been developed using archaeological material for differentiating between specimens belonging to cows, bulls and oxen. Whilst these techniques have been adopted widely by zooarchaeologists, in particular those studying medieval and post‐medieval tannery and horn‐working assemblages, they are highly subjective and their reliability has never been tested using material from cattle of known sex. This paper seeks to redress the balance. It presents the results of a study of 19th and 20th century cattle horn‐cores, from animals of known age, sex and breed, which were examined and measured in order to test the validity of traditional horn‐core sexing techniques. Previously claimed traits of sexual variation are here refuted, and a new metrical threshold for separating the males and females of ‘medium‐horned’ and ‘long‐horned’ types are presented. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
999.
Ancient bones in a good preservation state, ascertained by microscopic techniques, conserve extracellular matrix proteins over thousands of years. With new techniques, intact extracellular matrix proteins from ancient bones and teeth are extracted and separated by one‐dimensional and two‐dimensional electrophoresis. Proteins were identified in Western blots by special antibodies against different human extracellular matrix (ECM) molecules of bone. We have confirmed different types of ECM human bone molecules such as osteonectin, osteopontin, and alkaline phosphatase with specific antibodies in human bone samples from different age groups. Additionally, we selected bone samples from different cultural time periods, such as the Middle Ages, the Bronze Age and the Late Pre‐Pottery Neolithic Phase (PPNB), and teeth from individuals from the Early Middle Ages and from the Late PPNB. The survival of intact extracellular matrix proteins in ancient bones and teeth dating from recent times to the Late PPNB, and reliable techniques to identify these proteins, present a great challenge to further research. A Match Set with PD‐Quest 7.2 shows that only 16% of protein spots in the teeth are also found in the bone of the same individual. In combination with the results of macro‐ and microscopic investigation, biochemical techniques will help us in obtaining a better understanding of bone and teeth in health and disease. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
1000.
Investigation of modern biometric data indicates that it may be possible to distinguish wildcats from house cats in many instances. Applying the log‐ratio (log‐difference) technique to archaeological samples from medieval northern Europe, and to mixed samples of wildcats and house cats, shows that the differentiation may not always be clear, and the possibility that some samples include hybrids is discussed. The technique is applied to samples from the Orkney Islands to demonstrate that single wildcat specimens can be identified in small samples. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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