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991.
Jonas Lindberg 《Development and change》2010,41(1):131-151
To handle the double challenge of economic competitiveness and poverty alleviation, there are increasing calls for dual education strategies designed to handle both these issues simultaneously. Based on field research in rural Sri Lanka, this article aims to contribute to the understanding of how educational opportunities of different groups in different areas are shifting in the context of a changing world of work and new skill requirements in the global economy. An ongoing stratification of educational opportunities is identified, based on the growth of private tuition and English‐medium education, as well as a rationalization of the education system. The article shows that future attempts to reform the education system in Sri Lanka must be better rooted in the preferences and aspirations of poor groups in rural areas, and that educational opportunities must be seen as relative, relational and contextual. 相似文献
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The presence of the osseous remains of at least four mules in a garbage dump at the Roman fort of Biriciana near the town of Weißenburg, Upper Bavaria, dating to c. 160 AD, raised the question as to whether mule breeding was already performed to the north of the Alps during the Middle Roman Empire, or whether these animals still had to be imported from the Mediterranean. Serial analyses of the dental enamel and dentine of a lower fourth premolar and the surrounding alveolar bone of a mandible of a mule in terms of stable strontium isotopic ratios of the apatite, and stable carbon and oxygen isotope ratios of the structural carbonate, were carried out to test whether this individual moved long distances during its lifetime. Since isotopic ratios obtained by serial analysis can be correlated with consecutive ontogenetic stages, it can be assumed that this particular individual experienced significant changes in terms of diet and environmental parameters after its eighth year of life. These changes included a period of residence in a region of high altitude, most likely the Alps considering the location of the Roman fort where the mule was found. The isotopic data obtained do not contradict the assumption that this animal was bred and raised in northern Italy, to frequent later in its adult life the Alps and finally perish at Biriciana/Weißenburg. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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A. E. Van der Merwe G. J. R. Maat M. Steyn 《International Journal of Osteoarchaeology》2010,20(2):227-239
Examination of the histological structure of bone not only helps investigators to estimate age at death but can also aid in the diagnosis of palaeopathological lesions. The purpose of this paper is to assess whether histological features as described in the literature can confirm the macroscopic diagnoses of ossified subperiosteal haematomas associated with healed scurvy and syphilitic bone changes observed on the anterior tibiae of individuals from a 19th century mining community from Kimberley South Africa. The frequent occurrence of these two diseases amongst the deceased was well established in related hospital documents and governmental documents. A section of bone was removed from lesions on the tibiae of 14 individuals. These bone changes were macroscopically diagnosed as being indicative of either treponematosis ossified subperiosteal haematomas or non‐specific periostitis. Cross‐sections were prepared for microscopic investigation using a manual ground section technique. Ossified haematomas were histologically identified in seven individuals. These sections were characterised by normal cortical bone an intact original periosteal surface and newly formed radiating trabecular bone apposing it. Three phases of ossified subperiosteal haematoma formation and remodelling could be distinguished. Infectious bone changes most likely associated with treponematosis were observed in one individual. These were characterised by lysis and numerous resorption holes/channels. No clear distinction could be made between the internal spongy cortical or newly formed bone. Histological features described by some authors as characteristic of this condition could not be identified. In addition three individuals presented with microscopic features indicative of both the aforementioned bone affections and three did not show any pathological changes on microscopic level. It was concluded that although specific pathological conditions can most likely not be diagnosed purely on the basis of histomorphological observations broad distinctions could be made between lesions caused by the ossification of subperiosteal haematomas and bone changes due to infectious diseases. Copyright © 2009 John Wiley & Sons Ltd. 相似文献
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Osteoporosis is an evocative term for a metabolic disorder characterized by loss of bone mass and organization, which predisposes to fracture. The clinical consequences of osteoporosis lie in the problems associated with it, specifically hip, Colles and vertebral fractures. We present here an extracapsular fracture of the proximal femur in an aged female skeleton from the Santa Clara‐a‐Velha Monastery (14th–17th centuries) in Coimbra, Portugal. This fracture is probably secondary to an osteoporotic disorder. Bone remodeling at the fracture site confirms that this woman survived for a long period after sustaining a fracture of the proximal femur, suggestive of a solid community assistance and support. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献