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251.
Dominant development discourses often proclaim promises of economic prosperity and global inclusion, while actually disenfranchising local cultures in the Global South from their traditional environments. In Latin America, and specifically Chile, development manifests itself through neoliberal economic policies implemented in the late twentieth century, while simultaneously creating political economies ripe for foreign and corporate exploitation. Using a political ecology framework, this ethnography presents a case study of the correlation between the development of Chilean neoliberalism and the lifeways of Mapuche indigenous peoples in the town of Valle Elicura, Chile. The findings reveal that natural resource extraction and ecological devastation to local forests by large, international logging companies result in environmental, cultural, and environmental-cultural transformations for this community. The local people who more closely rely on their surrounding environments to regulate and inform their transportation networks, basic life needs, and religion, among other applications, are forced to compete for resources with foreign corporations focused on profit. However, it is this short-term focus that threatens extinction for the traditional lifeways of the Mapuche peoples and many other marginalised communities of facing the demands of development.  相似文献   
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We assessed the relationship between the quality (i.e., job characteristics, role stressors, and interpersonal relationships) and quantity of part-time employment, and work-related attitudes and aspirations among 349 students. Neither the linear nor the quadratic components of employment quantity predicted any of the outcome variables. Motivation to do good work was predicted both by role stressors and by family achievement orientation. Career maturity was predicted by role stressors at work, and cynicism by role stressors and satisfaction with interpersonal relationships. In contrast, job involvement was significantly related to family achievement orientation but not to any perceived job factors. These findings question the assumption that only intensive work during high school exerts negative effects for teenagers, and support the importance of employment quality for teenagers as well as adults. © 1998 John Wiley & Sons, Ltd.  相似文献   
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We describe two cases of sonographic abnormalities associated with unusual chromosomal aberrations. Case 1 presented with a cystic hygroma at 12 weeks' gestation. Cytogenetic analysis revealed an unbalanced complex chromosome rearrangement implicating chromosomes 6, 13 and 21 (karyotype: 47,XX,t(6;21;14)(q14;q21;q21)mat,+21) and corresponding to a complete trisomy 21. This anomaly resulted from malsegregation of a maternal balanced three-way translocation. For case 2, an alobar holoprosencephaly was identified by ultrasonography at 23 weeks' gestation. Chromosomal analysis showed a recombinant rec (13), dup q chromosome, secondary to unequal crossing-over of a paternal pericentric inversion of chromosome 13, giving rise to partial trisomy 13q (karyotype: 46,XX,rec(13)dup(13q)inv(13)(p11q21)pat). These two cases illustrate the role of ultrasound in leading to detection not only of foetal chromosomal aberrations but also of rare balanced chromosomal rearrangements presented by one of the two parents. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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This paper describes a preliminary evaluation of the performance of carbonaceous materials prepared from sewage sludges (SBCMs) in a hybrid water treatment process based on adsorption and catalytic wet air oxidation; phenol was used as the model pollutant. Three different sewage sludges were treated by either carbonisation or steam activation, and the physico-chemical properties of the resultant carbonaceous materials (e.g. hardness, BET surface area, ash and elemental content, surface chemistry) were evaluated and compared with a commercial reference activated carbon (PICA F22). The adsorption capacity for phenol of the SBCMs was greater than suggested by their BET surface area, but less than F22; a steam activated, dewatered raw sludge (SA_DRAW) had the greatest adsorption capacity of the SBCMs in the investigated range of concentrations (<0.05 mol L?1). In batch oxidation tests, the SBCMs demonstrated catalytic behaviour arising from their substrate adsorptivity and metal content. Recycling of SA_DRAW in successive oxidations led to significant structural attrition and a hardened SA_DRAW was evaluated, but found to be unsatisfactory during the oxidation step. In a combined adsorption–oxidation sequence, both the PICA carbon and a selected SBCM showed deterioration in phenol adsorption after oxidative regeneration, but a steady state performance was reached after 2 or 3 cycles.  相似文献   
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Hiking, horse riding and mountain biking are popular in protected areas in Australia and the United States of America. To help inform the often contentious deliberations about use of protected areas for these three types of activities, we review recreation ecology research in both countries. Many impacts on vegetation, soils and trails are similar for the three activities, although there can be differences in severity. Impacts include damage to existing trails, soil erosion, compaction and nutrification, changes in hydrology, trail widening, exposure of roots, rocks and bedrock. There can be damage to plants including reduction in vegetation height and biomass, changes in species composition, creation of informal trails and the spread of weeds and plant pathogens. Due to differences in evolutionary history, impacts on soil and vegetation can be greater in Australia than in the USA. There are specific social and biophysical impacts of horses such as those associated with manure and urine, grazing and the construction and use of tethering yards and fences. Mountain bike specific impacts include soil and vegetation damage from skidding and the construction of unauthorised trails, jumps, bridges and other trail technical features. There are gaps in the current research that should be filled by additional research: (1) on horse and mountain bike impacts to complement those on hiking. The methods used need to reflect patterns of actual usage and be suitable for robust statistical analysis; (2) that directly compares types and severity of impacts among activities; and (3) on the potential for each activity to contribute to the spread of weeds and plant pathogens. Additional research will assist managers and users of protected areas in understanding the relative impacts of these activities, and better ways to manage them. It may not quell the debates among users, managers and conservationists, but it will help put it on a more scientific footing.  相似文献   
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Noroviruses (NoVs), currently recognised as the most common human food-borne pathogens, are ubiquitous in the environment and can be transmitted to humans through multiple foodstuffs. In this study, we evaluated the prevalence of human NoV genogroups I (GI) and II (GII) in 493 food samples including soft red fruits (n = 200), salad vegetables (n = 210) and bivalve mollusc shellfish (n = 83), using the Bovine Enterovirus type 1 as process extraction control for the first time. Viral extractions were performed by elution concentration and genome detection by TaqMan Real-Time RT-PCR (RT-qPCR). Experimental contamination using hepatitis A virus (HAV) was used to determine the limit of detection (LOD) of the extraction methods. Positive detections were obtained from 2 g of digestive tissues of oysters or mussels kept for 16 h in seawater containing 2.0–2.7 log10 plaque-forming units (PFU)/L of HAV. For lettuces and raspberries, the LOD was, respectively, estimated at 2.2 and 2.9 log10 PFU per 25 g. Of the molluscs tested, 8.4 and 14.4 % were, respectively, positive for the presence of GI NoV and GII NoV RNA. Prevalence in GI NoVs varied from 11.9 % for the salad vegetables samples to 15.5 % for the red soft fruits. Only 0.5 % of the salad and red soft fruits samples were positive for GII NoVs. These results highlight the high occurrence of human NoVs in foodstuffs that can be eaten raw or after a moderate technological processing or treatment. The determination of the risk of infection associated with an RT-qPCR positive sample remains an important challenge for the future.  相似文献   
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