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51.
In the context of rising resource demand, agricultural crops such as sugarcane are being promoted for their multiple uses in different commodity markets and as alternatives to fossil fuel equivalents (i.e. as a source of biofuel, bioelectricity and bioplastic). These commodities are also produced on an increasingly flexible basis, as sugarcane mills respond to price signals and switch between different crop uses. This paper offers a preliminary exploration into the politics of this latest development in the capitalist industrialization of agriculture. It does so by focusing primarily on flexing in Brazil and highlighting the role of the state in both creating markets for non-food products that sugarcane mills can now switch between and managing the tensions that arise from this. These tensions have concerned consumer prices for fuel, control of distribution infrastructure and conditions of land conversion, each prompting political interventions by the state. The paper then suggests how this same process is taking place, albeit shaped by different contexts, in Southern Africa and Cambodia. It concludes with some key questions for further research: is flexing eroding the distinction between crop regimes? How do primary processors decide what their product mix will be? And on what basis do state actors support flexing between agricultural products and investments in so-called bio-refineries?  相似文献   
52.
Food production has been changing significantly in recent years as a result of climate change and of growing demand for food. This article aims to understand the link between food security and international security in the context of climate change, applying a systematic and qualitative analysis of the literature using the bibliometric method. This research observes that climate change tends to affect agricultural productivity, exposing societies to risk and the need for migration. However, good governance, together with international cooperation, can reduce the hazards of food insecurity, strengthening ties between countries and stimulating a fairer and more inclusive form of international trade.  相似文献   
53.
The Democratic Alliance of Hungarians in Romania (RMDSZ) has been the most stable actor in the Romanian party system over the past two decades. However, in this article, we argue that beyond this apparent stability, the linkages between RMDSZ and its voters have undergone a gradual, yet significant shift. The ethnic block voting of Transylvanian Hungarians was closely connected to the concept of a self-standing and parallel “Minority Society,” and to the practices of institution building that the minority elites engaged in in the early 1990s. However, since its first participation in the Romanian government in 1996, RMDSZ has gradually departed from this strategy, a phenomenon that was also closely connected to a process of elite change within the organization. The present RMDSZ leadership puts less and less emphasis on policy programs that could reinforce the institutional system of the minority; consequently, it is unable (and unwilling) to organizationally integrate the community activists of the minority society who previously had played a key role in the process of (electoral) mobilization. At the rhetorical level, RMDSZ did not abandon the goal of building a parallel Hungarian minority society, but in its linkages to the Hungarian electorate, clientelistic exchanges have become predominant.  相似文献   
54.
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   
55.
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   
56.

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   
57.
When using non-FTA cards in commercial multiplex STR kits for direct PCR, pretreatment steps with specific buffers are recommended. Here, we designed a rapid direct PCR method utilizing a non-FTA card, Oral Cell Sampling Kit, by omitting the pretreatment step involving Prep-n-Go™ Buffer, and it showed compatibility with the GlobalFiler™ Express PCR Amplification Kit, GlobalFiler™ PCR Amplification Kit, and PowerPlex® Fusion system. To optimize the PCR conditions, we tested the method with different final PCR volumes and cycles. Finally, we conducted a performance test using 50 Korean buccal samples and confirmed the high performance of the method, detecting more than 90% of the samples with full profiles when using GlobalFiler™ PCR Amplification Kit and PowerPlex® Fusion system at 29 cycles in a 10 μL final PCR volume. Thus, we report a simple direct PCR set-up to analyze reference samples collected using a non-FTA card manufactured in Korea.  相似文献   
58.
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline.  相似文献   
59.
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   
60.
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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