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61.
Abstract

The male/female sex ratio (SR) and its age-specific patterns vary considerably across time and place. The SR generally begins male-biased at birth and becomes female-biased later in life, but this relationship should respond to historical trends and events. Temporal trends in SRs remain largely unstudied and formal demographic relationships are not well defined. We (1) define SRs in a life table framework, (2) estimate the age at which the number of males and females achieves parity—the sex ratio crossover (SRX)—using basic life table methods, and (3) explore historical and international patterns in these trends. Using publicly-available data from the Human Mortality Database, we construct SR and SRX measures from period and cohort life tables. Analyses explore temporal patterns for seven countries in different global regions since 1850. Overall temporal trends show the SRX advancing to older ages. The SRX also appears to respond to historical events such as wars and epidemics. The measure is simple to construct from life table data, and provides additional insight into the historical context of gender dynamics.  相似文献   
62.
Abstract. This paper considers the Chechen secessionist struggle against Russia. Although the Chechens had good moral grounds for claiming independence in November 1991, this paper shows that Yeltsin also had reasons, defensible in legal terms and liberal secessionist theory, for rejecting it. Even if Moscow had granted Chechnya independence, this would not have created peace and stability. Moscow had a right to defend its territorial integrity, but its conduct in the war has proved counter‐productive. It has polarised opinion in Chechnya and made any solution to the crisis more difficult to achieve. On paper, Moscow's longstanding proposal of political autonomy for Chechnya looks the best way forward, but it is unlikely to satisfy Chechen nationalists or the Islamic fundamentalists who have more expansionist aims.  相似文献   
63.
For five decades it has been generally accepted that reserpine, an antihypertensive and antipsychotic drug, causes depression. The discovery that reserpine depletes brain monoamines was an important factor in the development of the monoamine hypothesis of depression, and it continues to be widely cited in support of this hypothesis. The present paper argues that, contrary to prevailing belief, reserpine is not depressogenic. The reason for perpetuation of this myth is reluctance to discard the monoamine hypothesis. This hypothesis ushered the modern biochemical paradigm into psychiatry and is still of great importance. It serves as a heuristic to guide research, it enhances psychiatry's prestige, and it helps to validate and promote drug therapy for depression and other mental disorders.  相似文献   
64.
Clinical examination of the reliability and coherence of the evidence concerning modern neurochemical theories of mental disorders has led some scholars to conclude that support for many of these theories is weak. Nevertheless, these theories continue to be widely promoted. One explanation that has been offered for continued adherence to questionable theory is that it stimulates and gives direction to research. The heuristic value of theory is examined in the present paper by tracing the discoveries that followed from an old theory of schizophrenia, which is--by current consensus--false. It is shown that the original serotonin hypothesis of schizophrenia did, in fact, lead to significant advances in neuropharmacology, neurology and psychiatry.  相似文献   
65.
Archaeobotanical research on prehistoric crops in Britain has primarily focussed on cereals and the potential importance of alternative crops, such as pulses, has often been overlooked. This paper reviews evidence for Celtic bean (Vicia faba L.) in British prehistory, using a database of archaeobotanical assemblages from 75 sites. Celtic bean is rare in the Neolithic – Early Bronze Age and it only becomes frequent from the Middle Bronze Age (ca. 1500 cal BC) onwards, particularly in southern England. Though there is a paucity of evidence at many sites, it is suggested that this reflects a preservation bias and in some areas at least, Celtic bean formed an important element of past agricultural systems.  相似文献   
66.
This paper shares Andersson’s interest in exploring the ‘backstage’ of Victorian civility and respectability. The adroit media manipulation of high-status leading reformers and their associations and societies, with their often overlapping membership, has accorded them an inflated importance as a representation of the Victorian Age, and can distort our understanding. The argument here begins by problematizing the ways some historians have made use of contemporary statistics and terms such as ‘respectability’ or ‘vice’. For the Victorians these carried multiple meanings and cultural resonances, partially dependent on identities of class, gender, generation, Tory or Liberal political orientation, attitude to faith, and ethnicity. This meant that the complex nuances of understanding attached to activities sometimes labelled as unrespectable ‘vices’ such as drinking, sexual transgression and gambling could make them acceptable in a variety of cultural contexts despite the opposition of vociferous anti-‘vice’ groups. The paper concludes with a brief exploration of the potentiality of visual and digital resources for delving deeper into such issues.  相似文献   
67.
The argument of this paper is that a deeper appreciation of the nature of the power relationships between firms and the circuits of power that bind them together is key to understanding how clusters function — including how they might emerge and how they might decline. We begin to develop a conceptualization that allows us to generate a deeper understanding of the processes that enable the production and reproduction of enterprise clusters under some combinations of circumstances but not others. The sections of the paper explore: (1) concepts of power and circuits of power including their spatialities; (2) the temporarily stabilized relationships which occur in clusters of economic activity; (3) the openness and permeability of clusters as a way of understanding conditions that foster cluster growth; (4) a tentative integration of concepts. From this reading of the concepts of clustering and power we draw the conclusion that clusters are, at any particular point in time, temporary and transient conjunctures of interfirm relationships. They depend on specific circumstances in 'time–space' and, because of their very transience and specificity, those conditions might be very difficult if not impossible to create through the blunt instruments of policy.  相似文献   
68.
69.
This article examines whether low-income countries can still benefit from participating in manufacturing global value chains (GVCs) in terms of broader industrial development in a global context of greater competition and higher requirements. It contends that developing internationally competitive local firms and domestic linkages, in addition to upgrading, is crucial for participation in GVCs to drive industrialization. The study focuses on Ethiopia's recent experience with developing an apparel export industry through strategic industrial policy. Based on original empirical data collected through firm-level surveys and interviews with government officials, industry experts and buyers, the article analyses the upgrading and localization trajectories of foreign and local apparel-exporting firms. It argues that value-capture benefits in assembly positions in apparel GVCs have become more difficult. The potential for localization benefits depends on the type of global buyers and foreign producers and their levels of embeddedness, but whether this potential is realized also depends on local firm characteristics and related industrial policy. Ethiopia's industrial policy has been relatively successful regarding national economy linkages, but less successful in developing competitive local export firms due to a weak local manufacturing tradition combined with a global context that has led to a supplier squeeze.  相似文献   
70.
The form and character of the British welfare state is undergoing another round of reform. Welfare modernisation now focuses on the creation of ‘aspirational citizens’ in deprived areas or communities, individuals, and groups who will ‘better’ themselves and become more like an imagined social ‘mainstream’. Old-fashioned policies that promoted expectations of improvement have been replaced by this focus on encouraging new forms of self-reliant, aspirational citizenship. This paper interrogates the nature of this discursive shift. It argues that an existential politics, built around notions of aspiration, is being rolled-out across the British welfare state and that this has significant material and political implications. It begins by critically assessing the terms aspiration and expectation. It then draws on recent urban and spatial policy agendas to empirically explore the nature of this shift and its wider effects on urban societies, economies, and environments before concluding with a discussion of possible future research directions and agendas.  相似文献   
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