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Drawing on recent scholarship on the financialization of agro-food systems and the global land grab, this paper examines new forms of financial investment in agriculture in the Canadian prairie provinces. We examine the factors underpinning investor involvement in the sector, including its anticipated financial performance as well as processes of agricultural restructuring that, combined with government actions to liberalize farmland ownership, have facilitated the enrollment of land and labour into new financial vehicles. We focus in particular on the emergence of two new forms of investment vehicles – farmland investment funds and an exchange-traded farming corporation – comparing the business model and investment strategy of each. In doing so, we highlight the ways in which the new investment patterns may propel the restructuring of the agricultural sector, alter power relations among key actors, and introduce new logics into the farming landscape. Our findings allow us to comment on the relevance of the land grabbing frame for making sense of the financialization of agriculture in the global North.  相似文献   
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In a further study of the thermal development of fingermarks on paper and similar surfaces, it is demonstrated that direct contact heating of the substrate using coated or ceramic surfaces at temperatures in excess of 230 °C produces results superior to those obtained using hot air. Fingermarks can also be developed in this way on other cellulose-based substrates such as wood and cotton fabric, though ridge detail is difficult to obtain in the latter case. Fluorescence spectroscopy indicates that the phenomena observed during the thermal development of fingermarks can be reproduced simply by heating untreated white copy paper or filter paper, or these papers treated with solutions of sodium chloride or alanine. There is no evidence to suggest that the observed fluorescence of fingermarks heated on paper is due to a reaction of fingermark constituents on or with the paper. Instead, we maintain that the ridge contrast observed first as fluorescence, and later as brown charring, is simply an acceleration of the thermal degradation of the paper. Thermal degradation of cellulose, a major constituent of paper and wood, is known to give rise to a fluorescent product if sufficient oxygen is available [1], [2], [3], [4], [5]. However, the absence of atmospheric oxygen has only a slight effect on the thermal development of fingermarks, indicating that there is sufficient oxygen already present in paper to allow the formation of the fluorescent and charred products. In a depletion study comparing thermal development of fingermarks on paper with development using ninhydrin, the thermal technique was found to be as sensitive as ninhydrin for six out of seven donors. When thermal development was used in sequence with ninhydrin and DFO, it was found that only fingermarks that had been developed to the fluorescent stage (a few seconds of heating) could subsequently be developed with the other reagents. In the reverse sequence, no useful further development was noted for fingermarks that were treated thermally after having been developed with ninhydrin or DFO. Aged fingermarks, including marks from 1-year-old university examination papers were successfully developed using the thermal technique.  相似文献   
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Abstract: Although the ability to develop latent fingerprints on paper using heat alone has been noted previously, it has been considered impractical for casework and inferior to other techniques. Here a new refinement of the technique is demonstrated for the high quality development of latent fingerprints on porous surfaces such as paper. Fingerprints deposited on various papers were developed by exposing them to hot air with a temperature in the vicinity of 300°C, for periods of c. 10–20 sec. Several different heating methods were tested. The novel observation was made that after shorter heating times, fluorescent prints could be observed. These became visible after longer heating times, as noted by earlier workers, but with greatly improved contrast compared with their results. Prints from various donors (and aged prints) were developed with excellent ridge contrast. Direct heating methods (such as with a hot plate or press) produced inferior results. The refined technique, which is simple, safe and inexpensive compared with conventional methods, has great potential for use in forensic laboratories.  相似文献   
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