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1.
Producing Power: Ethnicity, Gender, and Class in. Caribbean Workplace. Kevin A. Yelvington. Philadelphia: Temple University Press, 1995. 286 pp.
The Terror of the Machine: Technology, Work, Gender, and Ecology on the U.S.-Mexico Border. Devon G. Pena. Austin: Center for Mexican American Studies, University of Texas, 1997.460 pp.
Patriarchy on the Line: Labor, Gender, and Ideology in the Mexican Maquila Industry. Susan Tiano. Philadelphia: Temple University Press, 1994. 260 pp.  相似文献   

2.
《Anthrozo?s》2013,26(3):181-188
Abstract

Interviews were conducted with 24 graduating veterinary students to examine (a) changes in their attitudes toward animals; (b) the types of experiences and procedures that they found personally distressing; (c) their perceptions of the most important ethical issues that they will face in private practice; and (d) their responses to euthanizing animals. Students' responses differed considerably. For example, about half of the students claimed that they were not affected by euthanasia, but another 25% still were struggling with this aspect of their professional role. Rationalization was a common mechanism by which the students attempted to deal with stressful experiences. It is argued that the moral dilemmas faced by veterinary students mirror the ethical ambiguities inherent in human-animal relationships.  相似文献   

3.
As an indispensable virulence determinant, Salmonella pathogenicity island 1(SPI-1) has gained much attention in host–pathogen interactions. More and more studies on SPI-1 have demonstrated that it is far more complex than the one we used to expect. It not only affects sophisticated activities during infection, including invasion, replication, and host responses, but also extends to other fields like biofilm formation. In addition, mutants in SPI-1 effectors have been explored as vaccines, the effective ways to prevent salmonellosis. The activity of SPI-1 is influenced by many factors which have been widely reported. Investigations on these factors may provide new insights into prevention and treatment of salmonellosis. Therefore, SPI-1 is a tempting issue worthy of further exploration. In this review, we will probe into SPI-1 systematically.  相似文献   

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Hylema sp.5females oviposit on the undersides of sepals of developing buds of both Ipomopsis aggregata and Polemonium foliosissimum. Eggs deposited on the latter are significantly more likely to be fully protected by the sepal than are eggs deposited on the former. Unexposed eggs have a significantly greater likelihood of successfully developing to the larval stage than do exposed eggs. The difference in frequency of egg exposure on the two plant species can be attributed to differences in sepal morphology: I. aggregata sepals are significantly narrower than those of P. foliosissimum. The hypothesis that females preferentially oviposit on larger flowers was unconfirmed by a manipulative choice experiment. Plants differing in the size of their flowers were potted together and presented to Hylemya in arrays in the field. Flowers of the larger-flowered pair were no more likely to be oviposited on than flowers of the smaller-flowered pair. However, there were significant negative correlations between the corolla length and the percentage of flowers laid on per day at each of two sites. There was also a significant positive correlation between the corolla width and the percentage of flowers laid on at one site. Thus females appear to be using some measure of flower morphology, or a correlated trait, in making oviposition decisions. The degree to which Hylemya is making suboptimal choices between host plant species is discussed and requires further examination.  相似文献   

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This review examines the significance of foaming in bioprocesses, the mechanics of foam formation and destruction, and the methods of foam control and suppression. Emphasis is given to chemical antifoaming agents and characterization of their efficiencies. Criteria for selecting antifoaming agents are discussed.  相似文献   

8.
Manipulations of the environments of captive nonhuman primates often have welfare consequences to the animals, including behavioral effects, and for certain manipulations, physiological effects as well. The processes of transporting, relocating, and acclimatizing nonhuman primates across facilities represent manipulations that are likely to have welfare, behavioral, and physiological consequences to the relocated animals. Seventy-two chimpanzees were relocated from the Primate Foundation of Arizona (PFA) in Arizona to the Keeling Center (KCCMR) in Texas. Animals were transported for approximately 21 h in single cages in a USDA-approved, climate-controlled trailer. Chimpanzees were weighed, anesthetized, and blood samples were collected 1) immediately prior to departure from PFA, 2) immediately upon arrival at the KCCMR, and 3) at additional time point(s) between 3 and 12 weeks after arrival at the KCCMR. Chimpanzees were quarantined in familiar pairs or social groups for 60-90 days at the KCCMR. Blood samples were analyzed for hematological and clinical chemistry parameters and compared across time points. In addition, samples from a subset of animals were assayed for cell-mediated immune parameters. Comparisons of the data obtained just prior to transport, to the data obtained immediately upon arrival, revealed numerous statistically significant differences in hematological, clinical chemistry, and immunological parameters. Some of these were indicative of stress, and thus, changes in welfare state, although many remained within the published normal ranges for chimpanzees. Additional analyses showed that many of the clinical chemistry values collected 3 to 12 weeks after arrival at the KCCMR had returned to pre-transport values. In contrast, of the cell-mediated immune parameters that were affected by transport and relocation, few had returned to pre-transport levels 8 weeks after transport, and three of the four hematology variables analyzed had not returned to pre-transport levels 12 weeks after transport. Comparisons of body weights before and immediately after transport revealed that animals lost an average of 2.5 kg during the 21-h transport, a statistically significant reduction that some animals never regained. These results demonstrate that transport and relocation affect a variety of physiological parameters with potential welfare implications and that some of these effects last as long as 3 months. These findings have important implications for the welfare and use of recently transported nonhuman primates, especially chimpanzees, in biomedical research. In order to allow animals to adapt to their new surroundings and to prevent unwanted confounds from influencing experiments, sufficient time must be provided after transport for chimpanzees to acclimatize.  相似文献   

9.
Many employees in service work are required to work on Saturdays, recovering during work-free Sundays and working again Mondays. We examined the effects of social stressors at work on recovery status at Sunday noon and Monday noon, and investigated if sleep quality mediates the negative effects of social stressors at work on recovery. From Saturday until Monday morning, 41 participants wore actigraphs to measure sleep duration and sleep fragmentation. Social stressors at work were assessed by self-reported questionnaires administered on Saturday. Recovery status was reported Sunday noon and Monday noon. Hierarchical regression analysis revealed that social stressors at work were negatively related to recovery status on Sunday and on Monday. Supporting our assumptions, more social stressors at work predicted higher sleep fragmentation in the night to Monday. A mediation effect of sleep quality, however, was not found. Theoretical and practical implications of these results are discussed.  相似文献   

10.
Chetverikova  E. P. 《Biophysics》2011,56(2):309-315
The question about the correspondence of regenerants after cryopreservation to the initial organisms has long been in the focus of attention of cryobiologists. The correspondence has been established for morphological and physiological characteristics and the DNA composition in flower plants and algae. However, at least as many works point to some phenotypic changes and appearance of DNA polymorphism in representatives of both plant kingdoms. Changes in DNA methylation at cytosine after cryopreservation of flower plant tissues have attracted considerable interest. Thus, after freezing and thawing, changes in the phenotype and genome may occur, and the latter involve two mechanisms: mutations and modification of DNA methylation.  相似文献   

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The Price of Poverty: Money, Work, and Culture in the Mexican American Barrio . Daniel Dohan. Berkeley: University of California Press, 2003. 314 pp.  相似文献   

13.
Illingworth P 《Bioethics》1990,4(4):340-350
Private Acts, Social Consequences by Ronald Bayer. New York, The Free Press, Macmillan, Inc., 1989, 282 pp., $US 22.95.  相似文献   

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Harmful Cyanobacterial Blooms: Causes, Consequences, and Controls   总被引:8,自引:0,他引:8  
Cyanobacteria are the Earth’s oldest oxygenic photoautotrophs and have had major impacts on shaping its biosphere. Their long evolutionary history (~3.5 by) has enabled them to adapt to geochemical and climatic changes, and more recently anthropogenic modifications of aquatic environments, including nutrient over-enrichment (eutrophication), water diversions, withdrawals, and salinization. Many cyanobacterial genera exhibit optimal growth rates and bloom potentials at relatively high water temperatures; hence global warming plays a key role in their expansion and persistence. Bloom-forming cyanobacterial taxa can be harmful from environmental, organismal, and human health perspectives by outcompeting beneficial phytoplankton, depleting oxygen upon bloom senescence, and producing a variety of toxic secondary metabolites (e.g., cyanotoxins). How environmental factors impact cyanotoxin production is the subject of ongoing research, but nutrient (N, P and trace metals) supply rates, light, temperature, oxidative stressors, interactions with other biota (bacteria, viruses and animal grazers), and most likely, the combined effects of these factors are all involved. Accordingly, strategies aimed at controlling and mitigating harmful blooms have focused on manipulating these dynamic factors. The applicability and feasibility of various controls and management approaches is discussed for natural waters and drinking water supplies. Strategies based on physical, chemical, and biological manipulations of specific factors show promise; however, a key underlying approach that should be considered in almost all instances is nutrient (both N and P) input reductions; which have been shown to effectively reduce cyanobacterial biomass, and therefore limit health risks and frequencies of hypoxic events.  相似文献   

16.
Anthropology at the Edge: Essays on Culture, Symbol, and Consciousness. J. Ian Prattis. Lanham, MD: University Press of America, 1997. 311 pp.  相似文献   

17.
SYNOPSIS. The degree to which a female partitions resourcesbetween fecundity and per offspring investment is a centralquestion in life-history theory. Maternal effects may influencethe nature of this tradeoff through their effect on per offspringinvestment and subsequent offspring fitness. The purpose ofthis study was to determine the effect of female age and sizeon brood size (number of offspring), per offspring investment,and fitness in the polychaete Streblospio benedicti. Early stageembryos were collected from brooding females of known age andsize over a period of 100 days; these embryos were counted andanalyzed for their C and N content. Female size had a positiveeffect on brood size; larger females produced larger broods.However, brood size decreased with female age (females did notincrease in size after reaching sexual maturity). Brood sizedeclined 20–46% between 60 and 160 days of age. Duringthis same age period per offspring investment, measured in termsof C and N, increased by 25%. Offspring survivorship and sizeat two weeks post-release from the female were used as measuresof offspring fitness. Offspring survivorship increased 28% between60 and 160 days of age. Increased growth in offspring from olderfemales resulted in a 23% increase in offspring size at twoweeks. Including the maternal age effect in two population modelsfor S. benedicti increased population growth rate (). Populationgrowth was increased to a greater degree when the maternal effectwas modeled by enhancing offspring survival compared to whenfecundity was increased by the same proportional amount. Thissuggests that the maternal effect may be adaptive, particularlywhen conditions for offspring survival and growth are poor.  相似文献   

18.
Inbreeding is said to reduce vigour and fitness. It may also determine how a population responds to selection. Local populations of Callosobruchus maculatus , the cowpea seed beetle, are established annually from small numbers of founders and the species has been distributed to many parts of the world where isolated populations may have been founded by very small numbers of individuals. After more than 20 generations of inbreeding, inbred lines have been shown to diverge from a common ancestral stock in similar directions with respect of some variables such as developmental speed, but haphazardly in respect of other parameters such as male weight. The respective roles of drift and of selection as effective evolutionary forces in inbred lines are discussed in the light of these results. It is argued that some intraspecific differences in C. maculatus may be explained as a product of periodic inbreeding, but that the process does not impair the ability to adapt to local conditions so contributing to the status of the species as a pest of international importance.  相似文献   

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