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261.
In this article we first point out that the different conceptualisations of Fair Trade, which are sometimes analytically contradictory, actually form a coordinated set. Understanding the Fair Trade project is impossible without taking these interlinked conceptualisations into consideration. Second, this set basically forms a mechanism of structural, institutional and moral reforms that guide actions. In this way Fair Trade sets out to produce less injustice than is usually the case with the structures and institutions that govern conventional trade. Nevertheless, it does not try to define what a just society is or even to perfectly define ‘fair trade’. This implies the adoption of a comparative justice angle. It is precisely by linking comparative individual situations with the structures that produce these situations that relative justice can find its strength and purpose.  相似文献   
262.
Studies of Brazil's agricultural labor movement have generally neglected its relationship to the struggle for land, but this is neither fair nor accurate. Analyzing the rural labor movement's historical contributions to the land struggle in Brazil, this contribution has been organized into three main periods, emphasizing social relations, institutional activism and policy changes. It argues that despite the peculiarities of different historical contexts, rural labor consistently provoked protest against policies that privileged large landholders, whose concentration of power over land and labor resources continually worsened Brazil's ranking as one of the most unequal of nations. For more than half a century, the most constant opponent of this situation among the peasantry has been the National Confederation of Workers in Agriculture (CONTAG), a corporatist organization of rural labor unions founded in 1963.  相似文献   
263.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.

Key points

  • Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
  • Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
  • These metrological principles also apply to individuation of unique objects in general.
  相似文献   
264.
This study focuses on the role of public capital stock in contributing to interstate differences in productive efficiency in manufacturing. Our motivation is to assess the role of public capital as a source of persistent regional variations in efficiency, and thus determine if public infrastructure policies might reasonably be expected to alter the competitive environment of a state's manufacturing sector. We use a stochastic frontier production function model, explicitly incorporating infrastructure capital, to examine the relative performance of the aggregate manufacturing sector across states and over time. We calculate an index of productive efficiency and estimate the determinants of statewide variations in it. These results show that variations in per capita infrastructure stocks significantly affect manufacturing efficiency. Considering the behavior of public capital as both a direct and an indirect input furthers our understanding of the role of infrastructure and its implications for regional economic development policies.  相似文献   
265.
Coleman D  Casey JT 《危机》2007,28(4):198-203
The treatment processes associated with reduced suicidal ideation have received little research attention. This study evaluates the influence on suicidal ideation of theory-based intrapsychic processes: maladaptive cognition and defensive style. Thirty-three community mental health patients completed questionnaires at two time points. Decreases in automatic thoughts were a strong correlate of decreased suicidal ideation, and decreases in immature defenses were a moderate strength correlate. These relationships remained significant even when controlling for initial level of depression. The theorized mechanisms of cognitive-behavioral and psychodynamic therapy had the expected effects on suicidal ideation. The strong association of decreased maladaptive cognitions with decreased suicidal ideation supports further development of cognitive-behavioral suicide interventions and clinical use of cognitive interventions. Psychodynamic processes in suicidal ideation and behavior warrant further exploration.  相似文献   
266.
Milk maids     
Lee-St John J 《Time》2007,169(18):65
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267.
大学是创新和社会进步的源泉   总被引:1,自引:0,他引:1  
大学是创新和社会进步的源泉。大学不仅可以支持并推动知识进步,更重要的贡献在于新发明和创新。由于大学长期关注基础性研究,因而比其他机构更容易开展创新活动。大学通过创新提高人们的生活水平、推动经济发展,进而推动社会的进步。易于创新的研究环境必须具有必要的内外部条件。内部条件主要有三个:一是要选对人;二是要时刻处于技术的前沿;三是要寻找那种跨越性的技术。外部条件主要有两个:一是大学与业界应互相尊重、相辅相成,形成双赢局面;二是创新的转化需要为技术突破提供肥沃的土壤和精心的照料。  相似文献   
268.

Identity and academic motivation are particularly at stake before the major transition to higher education. However, few studies have explored their changes and their longitudinal bidirectional links. To fill this gap, a three-wave study from the end of the 11th grade to the end of the 12th grade was conducted to explore changes in identity processes and academic motivation and to investigate how they might be interconnected over time. 599 adolescents (mean age 17.4; 59% girls) completed questionnaires containing measures about identity processes and three types of academic motivation: autonomous, controlled, and impersonal. Throughout the study span of one year, four identity processes increased: commitment making, identification with commitment, exploration in breadth and exploration in depth, while the process of ruminative exploration decreased. Simultaneously, late adolescents encountered an increase in impersonal motivation, more salient for boys. The results also revealed unidirectional links from motivation to identity processes, with no gender or age moderator effects: exploration in breadth and exploration in depth were positively predicted by autonomous motivation, ruminative exploration was positively predicted by autonomous, controlled, and impersonal motivation. In addition, impersonal motivation negatively predicted commitment making. On the other hand, identification with commitment positively predicted autonomous motivation. Practical implications are discussed.

  相似文献   
269.
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
270.
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method.  相似文献   
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