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1.
One of the most important phases of case‐oriented research is identifying the relevant population of cases. The best practice scheme suggests first identifying the positive and then the negative cases, based on the assumption that the population is small and known. This scheme is inapplicable when the population is unknown, as is the case with many public administration and public policy outcomes, which are often less visible. However, most research either ignores this difficulty or recommends a single case study. This article suggests that when the population is unknown scholars can apply the possibility principle to identify the relevant population of cases. In order to do so, a large dataset is required. In policy studies, the Comparative Agendas Project (CAP) can serve this aim. This article highlights CAP's applicability for case selection based on the possibility principle in two less visible policy outcomes: conversion and drift. In that, it not only addresses an overlooked challenge but also promotes both CAP as a useful tool for qualitative researchers and the expansion of comparative work on conversion and drift.  相似文献   
2.
An example of ante‐mortem cranial perforations in the skull of a European wisent (Bison bonasus) from Armenia is presented. The implications for reinterpreting the possible causes of this condition in ancient domestic cattle (outlined in a previous paper) are briefly discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
3.
The fluorite deposits of Asturias (northern Iberian Peninsula) are hosted by rocks of Permo‐Triassic and Palaeozoic age. Fluid inclusions in ore and gangue minerals show homogenization temperatures from 80 to 170°C and the presence of two types of fluids: an H2O–NaCl low‐salinity fluid (<8 eq. wt% NaCl) and an H2O–NaCl–CaCl2 fluid (7–13 wt% NaCl and 11–14 wt% CaCl2). The low salinity and the Cl/Br and Na/Br ratios (Cl/Brmolar 100–700 and Na/Brmolar 20–700) are consistent with an evaporated sea water origin of this fluid. The other end‐member of the mixture was highly saline brine with high Cl/Br and Na/Br ratios (Cl/Brmolar 700–13 000 and Na/Brmolar 700–11 000) generated after dissolution of Triassic age evaporites. LA‐ICP‐MS analyses of fluid inclusions in fluorite reveal higher Zn, Pb and Ba contents in the high‐salinity fluids (160–500, 90–170, 320–480 p.p.m. respectively) than in the low‐salinity fluid (75–230, 25–150 and 100–300 p.p.m. respectively). The metal content of the fluids appears to decrease from E to W, from Berbes to La Collada and to Villabona. The source of F is probably related to leaching of volcanic rocks of Permian age. Brines circulated along faults into the Palaeozoic basement. Evaporated sea water was present in permeable rocks and faults along or above the unconformity between the Permo‐Triassic sediments and the Palaeozoic basement. Mineralization formed when the deep brines mixed with the surficial fluids in carbonates, breccias and fractures resulting in the formation of veins and stratabound bodies of fluorite, barite, calcite, dolomite and quartz and minor amounts of sulphides. Fluid movement and mineralization occurred between Late Triassic and Late Jurassic times, probably associated with rifting events related to the opening of the Atlantic Ocean. This model is also consistent with the geodynamic setting of other fluorite‐rich districts in Europe.  相似文献   
4.
This article explores the existence of customary laws relating to ‘traditional’ knowledge of plants in Thailand through micro‐ethnographic case studies. This is juxtaposed against global and national frameworks of intellectual property laws that have a privatising effect on knowledge under the rubric of discovery or ‘invention’, as well as liability rights approaches of compensation and benefit‐sharing for research access. By understanding scale and legal jurisdiction as socially and politically constructed phenomena, we explore how laws at different scales and in different jurisdictions may override each other, discriminate against foreign laws and practices, and ignore customary laws. In doing so, the paper presents complex legal geographies of plants and associated knowledge, which suggest that the customary laws and norms of Indigenous groups and traditional healers are often ignored by ‘outsiders’. The paper notes that the possibility of ‘injury’ to traditional healers remains considerable without appropriate consent and given the discriminations surrounding knowledge made by patent laws. However, the ethnographies also point to the possibility of local remedies to these injuries through ritual processes, and we note resistant co‐constitutions of law and scale through the Nagoya Protocol.  相似文献   
5.
基于SEA的AGA-SVR节假日客流量预测方法研究   总被引:2,自引:0,他引:2  
节假日旅游客流量由于游客在短期内大量集中于同一地点、不同节假日休假时间长短、所处季节等不同,呈现复杂非线性特征和明显季节性特点.本文提出一种基于季节指数调整(Seasonal Exponential Adjustment,SEA)的自适应遗传算法(Adaptive Genetic Algorithm,AGA)-支持向量回归 (Support Vector Regression,SVR)预测模型,即基于SEA的AGA-SVR模型,并用国内著名5A级风景区黄山2008~2012年节假日客流量数据对模型进行验证.研究结果表明,基于SEA的AGA-SVR预测模型能够准确处理节假日旅游客流量预测中的非线性和季节性问题,较AGA-SVR和GA-SVR等方法具有更高的预测精度,在旅游预测领域应用前景广阔.  相似文献   
6.
The popularity of books such as Yuval Noah Harari's Sapiens: A Brief History of Humankind suggests that universal history‐writing has a continuous not a broken past. Rather than “returning,” it is perhaps the most enduring genre of all. This review essay explores the deep‐history element of universal histories and the ongoing purchase of the stadial tradition for a new history of the species. Why are deep histories of the species so reliably appealing, and what do they mean in the twenty‐first century? Although the Anthropocene would seem to be the pertinent context for this ongoing historiography, this essay suggests that the new domain of genetic genealogy powerfully individualizes and commercializes deep history for neoliberal times.  相似文献   
7.
Over a period of some 100 years it has gradually been accepted that the human skeletal remains found in the late nineteenth century in ancient gravels at Galley Hill, Kent are not those of early man, but are of much more recent date. This conclusion was finally verified by means of relative (N, F) and absolute (14C) dating. Here we present the results of further analysis of the remains from Galley Hill for their uranium content by a method having general application to the relative dating of fossil human and other mammalian bone.  相似文献   
8.
The transition from hunter-gathering to agriculture (Neolithic) spread gradually across Europe from the Southeast. A reduction in cultural diversity of crop farming practices has been previously observed by comparing pre-LBK Neolithic sites in Greece and the Balkans (dated about 8500 yr BP) to LBK Neolithic sites in Central Europe (dated about 7000 yr BP). The decrease in crop diversity is statistically significant even when considering only the species less likely to have been subject to smaller productivity due to climatic factors (reductions in growing season, temperature, daylight, etc.). This reduction in cultural diversity has not been explained previously. In this paper we show that spatial drift, which occurred on the front of the advancing wave of pioneer settlements, can explain the observed loss of diversity during the LBK range expansion. Our results suggest that spatial dimensions can have a relevant effect also in other case studies in which cultural drift is important.  相似文献   
9.
This essay considers the mid-twentieth century adoption of genetic explanations for three biological phenomena: nutritional adaptation, antibiotic resistance, and antibody production. This occurred at the same time as the hardening of the neo-Darwinian Synthesis in evolutionary theory. I argue that these concurrent changes reflect an ascendant narrative of genetic selfhood, which prioritized random hereditary variation and selection through competition, and marginalized physiological or environmental adaptation. This narrative was further reinforced by the Central Dogma of molecular biology and fit well with liberal political thought, with its focus on the autonomous individual. However, bringing biological findings into line with this narrative required modifying the notion of the gene to account for various kinds of non-Mendelian inheritance. Hans-Jörg Rheinberger's reflections on narrative and experiment are valuable in thinking about the friction between the postwar ideal of genetic selfhood and actual observations of how organisms adapt in response to the environment.  相似文献   
10.
This review considers four recent works on in vitro fertilization; human egg donation; the relation among family, kinship and nature; genetic databases, and medical research. Assisted reproductive technology has increasingly become a tool for the artificial production of body parts. Anthropology is reformulating kinship and family theories, taking into account their relationship with biology (in the strict sense of body) and technology as primary “agents” of reproduction and the socio-cultural constitution of selves.  相似文献   
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