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It is suggested that Mench give credit to the books that started the farm animal welfare movement--Harrison's (1964) Animal Machines and, arriving 1 year later, Huxley's (1965) Brave New Victuals. Huxley covered the use of chemicals on the land and "factory fanning," a phrase coined by Harrison. They both discussed the rearing of animals indoors in huge numbers, closely confined, artificially lit, mechanically supplied with food, and treated with drugs and hormones to prevent disease and to speed growth. Are intensive methods necessarily cruel to animals? Are agricultural and industrial chemical residues contaminating the environment? What is the influence of new methods on the quality of food and what are the effects on the human organism? These were relevant questions back then, and almost 30 years later Harrison (1988, 1993) wondered how much real progress has been made in answering them.  相似文献   

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The Study of Territoriality: Complexities and Future Directions   总被引:1,自引:0,他引:1  
Each paper in an American Society of Zoologists' symposium onterritoriality generated new ideas for future research. However,since similar themes repeatedly arose, an overview of the symposiumrevealed the areas in which future research is most needed.Theory far outstrips data on territoriality at this point, andefforts should concentrate on field tests of ideas. Some ofthe general areas that need study are: the effect of foraginggoals and constraints on territorial decisions, the effect ofthe internal energy or breeding state of the animal in makingterritorial decisions, the effects of subtle factors such ashabitat geometry and the role of neighbors on the cost of defense,the effect of various forms of environmental variability onterritorial decisions, the active or passive influence of plantson territoriality, and the effect of scale and mobility in theexpression and evolution of territoriality. The study of territorialityis entering a particularly challenging stage of development,because study systems must be carefully chosen and model assumptionsthoroughly examined before rigorous experimental tests of hypothesescan be performed. Yet the state of the art is such now thatonly rigorous tests will advance our knowledge further.  相似文献   

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The starchy swollen roots of cassava provide an essential food source for nearly a billion people, as well as possibilities for bioenergy, yet improvements to nutritional content and resistance to threatening diseases are currently impeded. A 454-based whole genome shotgun sequence has been assembled, which covers 69% of the predicted genome size and 96% of protein-coding gene space, with genome finishing underway. The predicted 30,666 genes and 3,485 alternate splice forms are supported by 1.4 M expressed sequence tags (ESTs). Maps based on simple sequence repeat (SSR)-, and EST-derived single nucleotide polymorphisms (SNPs) already exist. Thanks to the genome sequence, a high-density linkage map is currently being developed from a cross between two diverse cassava cultivars: one susceptible to cassava brown streak disease; the other resistant. An efficient genotyping-by-sequencing (GBS) approach is being developed to catalog SNPs both within the mapping population and among diverse African farmer-preferred varieties of cassava. These resources will accelerate marker-assisted breeding programs, allowing improvements in disease-resistance and nutrition, and will help us understand the genetic basis for disease resistance.  相似文献   

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The Past in the Future: History and the Politics of Identity   总被引:1,自引:0,他引:1  
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Astrocytes make up 20–40% of glial cells within the central nervous system (CNS) and provide several crucial functions, ranging from metabolic and structural support to regulation of synaptogenesis and synaptic transmission. Although these cells are morphologically and functionally complex, astrocytes have been historically regarded as homogenous cell populations and studied as one population of cells. Fortunately, recent evidence in RNA profiling and imaging data has begun to refute this view. These studies suggest heterogeneity of astrocytes across brain regions, differing in many aspects such as morphology, function, physiological properties, developmental origins, and response to disease. Increased understanding of astrocyte heterogeneity is critical for investigations into the function of astrocytes in the brain and neuro–glia interactions. Furthermore, insights into astrocyte heterogeneity can help better understand their role in neurological disorders and potentially produce novel approaches to treating these diseases.

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Binge eating disorder (BED) is a newly characterized eating disorder that encompasses individuals who have severe distress and dysfunction due to binge eating, but who do not regularly engage in inappropriate compensatory behaviors. While relatively uncommon in the general community, BED becomes more prevalent with increasing severity of obesity. BED is associated with early onset of obesity, frequent weight cycling, body shape disparagement, and psychiatric disorders. These associations occur independent of the degree of obesity. Although many individuals with BED have good short-term weight loss regardless of treatment modality, as a group they may be prone to greater attrition during weight-loss treatment and more rapid regain of lost weight. Current treatments geared toward binge eating behaviors include antidepressant medications, cognitive behavioral psychotherapy, and interpersonal psychotherapy; however, these treatments have little efficacy in promoting weight loss, and only modest success in long-term reduction of binge eating. As a significant proportion of obese individuals entering weight-loss treatment and research programs are likely to meet criteria for BED, those conducting clinical research should be aware of this distinct subgroup and determine the contribution of BED to outcome measures. (OBESITY RESEARCH 1993; 1:306–324)  相似文献   

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Anorexia is a common complication in patients with chronic kidney disease (CKD) and is associated with the development of malnutrition and an increased risk of mortality. Several compounds are linked to anorexia in these patients; however, the mechanisms are unknown. Zinc (Zn) deficiency is associated with decreased food intake and has been observed in CKD patients. In addition, leptin is an anorexigenic peptide, and patients with CKD present generally high levels of this hormone. Studies have suggested an association between Zn and leptin status in human and rats; however, the results are inconsistent. Some claimed that Zn supplementation does not change leptin release or that there is no significant relationship between Zn and leptin. Others have reported that Zn might be a mediator of leptin production. CKD patients have hyperleptinemia and hypozincemia, but the relationship between Zn deficiency and leptin levels in CKD patients has been poorly understood until now. The aim of this review is to integrate knowledge on leptin and Zn actions to provide a cohesive clinical perspective regarding their interactions in CKD patients.  相似文献   

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