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201.
The Dasht‐e‐Kawir in central Iran is a catchment, which includes saline, swampy areas and sandy land.

The system of water supply in the margins of the Dasht‐e‐Kawir is limited by the amount of underground water which can be extracted by qanats and wells.

Six kinds of qanats and two kinds of shallow wells have been recognized in the region.

A qanat is usually produced in six stages, of which measurement of the gradient is the most crucial for its successful construction. Thus, the construction of thirty qanats in the margin of Dasht‐e‐Kawir has been studied to determine the logical relationship between (a) the gradient, (b) the depth of main well, (c) the length and (d) the discharge of the qanat.  相似文献   

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204.
From the deep sense of frustration about the gap between what is possible and what is actually happening, a clear consensus emerged at the XIV International AIDS Conference that effective action is urgently required. This article is based on a presentation on 12 July 2002, the last day of the conference, by Terje Anderson, the rapporteur for Track G. The article presents a summary of the discussions in Track G on topics such as advocacy strategies, the use of the law, the use of a human rights framework and approach, the role of people living with HIV/AIDS, and the need to mobilize sufficient resources. The article states and then critically examines some of the consensus positions that emerged from the conference--specifically, the goal to have three million people on antiretroviral therapy by 2005; the notion that the debate around prevention versus care is over; and the idea that the key issue is no longer what we do, but how to secure the commitment and the resources to do it. The article states that the fight against HIV/AIDS must be fought on a political plane, and that it is the responsibility of everyone working in AIDS to engage our leaders. The article concludes by asking whether we really have the courage and the perseverance to turn our knowledge and our commitment into action.  相似文献   
205.
Does ink age inside of a pen cartridge?   总被引:2,自引:0,他引:2  
In questioned document examination and ink dating, it has been assumed that the ink inside of a pen cartridge does not begin aging until the ink is dispensed onto paper. Positive ion laser desorption (LD) mass spectra were obtained of ink-on-paper samples containing methyl violet, from new and old pens. Mass spectral studies with methyl violet have established the mechanism for how the dye degrades over time, and have provided structural information concerning the dye's degradation products. This information was used as an indication of the relative age of ink on paper. The LD mass spectrum of the ink from a new pen was indicative of "new" ink, whereas the spectra of the ink found in some older pens may appear to be either new or old. The ink from most of the old pens studied appears not to have aged, supporting the common assumption, whereas other ink samples produced "aged" ink spectra, suggesting otherwise.  相似文献   
206.
Rupture of a splenic artery aneurysm is a rare and usually catastrophic event, most commonly associated with pregnancy. In spite of increasingly common reliance on abdominal angiography, magnetic resonance imaging, and computerized tomography during the past quarter century, clinicians uncommonly recognize any of the various splanchnic arterial aneurysms absent premonitory signs or symptoms. Accordingly, rupture of a visceral aneurysm, including splenic artery aneurysm, typically presents as sudden, unexpected obtundation or death. As a consequence, the initial recognition and diagnosis of splenic artery aneurysm rupture take place only at autopsy. This report presents two such cases of sudden death resulting from splenic artery aneurysm in a pregnant woman and a postpartum woman, respectively.  相似文献   
207.
Sudden unexpected death in epilepsy: neuropathologic findings   总被引:4,自引:0,他引:4  
Sudden unexpected death in epilepsy refers to sudden death of an individual with a clinical history of epilepsy, in whom a postmortem examination fails to uncover a gross anatomic, toxicologic, or environmental cause of death. Evidence of terminal seizure activity may not be present. One to two percent of natural deaths certified by the medicolegal death investigator are attributed to epilepsy. Detailed microscopic examination of the brain has increasingly afforded the identification of structural changes representative of epileptogenic foci. The authors present 70 cases of death attributed to sudden unexpected death in epilepsy. These cases were classified as follows: individuals who lacked a gross brain lesion, those who had a brain lesion demonstrable at autopsy, and those who lacked neuropathologic evaluation because of decomposition or because only an external examination was done. All of the subjects had a clinical history of seizures. The authors confirm that various microscopic findings, including neuronal clusters, increased perivascular oligodendroglia, gliosis, cystic gliotic lesions, decreased myelin, cerebellar Bergmann's gliosis, and folial atrophy, are present in a higher percentage of the brains of sudden unexpected death in epilepsy subjects than in the brains of age- and sex-matched control subjects.  相似文献   
208.
  • This paper builds upon a content analysis of all news articles that appeared in six national daily newspapers and of all national press releases issued by the three main political parties during the UK General Election 2001 campaign. The results were compared with data from two opinion polls conducted at the start and at the end of the campaign. Here, using the same basic data, we track the coverage of issues in party press releases and daily newspapers on a weekly basis to determine how the parties' priorities and press coverage evolved.
  • The results show that the Labour and Liberal Democrat campaign strategies, in terms of relative issue priorities, did not change during the campaign. However, the Conservatives shifted their attention to the public priorities of Health and Education towards the end of the campaign. There is evidence that the Conservative emphasis on Europe and taxation earlier in the campaign may have influenced the volume of press coverage but did not appear to have affected relative party standings. The implications of these results for political marketers are considered.
Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
209.
This article examines proto-industrialization and the social relations of production in a rural parish in eastern Westphalia that experienced large-scale outmigration to the American Midwest in the mid-nineteenth century. Relying on local and individual-level Prussian tax and emigration records, the study identifies and analyses the socio-economic background of the migrant cohort in terms of proto-industrial activity and peasant economy. Preceded by the downfall of domestic textile industries due to British industrial competition, outmigration was highly selective, drawing individuals from specific socio-economic niches. Landless sharecroppers - linked by debt and labour obligations to better-off peasants and landlords - were underrepresented in the migration, while smallholding peasants and day-labourers - 'free' to commodify their labour power through the sale of home-produced textile products or seasonal migratory labour - were overrepresented. The findings of the study have implications for an understanding of the localized nature of the relations of production in proto-industrial regions, the historical nature of German emigrations, and the dynamics of the German transition to industrial capitalism in the nineteenth century.  相似文献   
210.
A simple, reliable, and relatively accurate method for estimating the time since death is described. It is based on the Triple-Exponential Formulae (TEF), which are devised for the first time in this study. The postmortem cooling rate of the brain, liver, and rectum in 117 forensic cases were investigated (Part I). The method can be used in the field as a computer program, reference graph, or reference chart-ruler. The program is simple and can easily be run by any user. There are six reference graphs representing the average brain, liver, and rectal cooling curves for naked and covered body groups. The ruler is designed for the rectal cooling curves for covered and naked bodies. This method requires one temperature measurement of the chosen body site and the environment. The postmortem interval is estimated as a probable value +/- a possible range of time estimates with a built-in confidence limit.  相似文献   
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