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51.
转基因微生物生态学及大田释放风险评价研究 总被引:15,自引:4,他引:11
向环境中释放转基因微生物可能会带来一系列的安全问题.在大面积释放之前必须对转基因微生物在环境中发生基因转移的潜力、存活能力、扩散能力及对生态系统的潜在影响等进行生态学研究和风险评价,同时还要探索有效的检测方法和风险评价策略.该研究有助于分子生态学的发展和生物技术的安全应用,具有重要的理论和实践意义. 相似文献
52.
Diane E. Eyer 《Human nature (Hawthorne, N.Y.)》1994,5(1):69-94
A study of the research on postpartum mother-infant bonding shows that results from poorly constructed research programs were
published in major journals and became a part of hospital policy because the bonding concept was politically useful in the
struggle between advocates of natural childbirth and managers of the medical model of birth. The concept was also uncritically
accepted because it was consistent with a longstanding ideology of motherhood that sees women as the prime architects of their
children’s personalities.
Diane Eyer earned her Ph.D. in developmental psychology from the University of Pennsylvania. She is currently writing a book
on the ways in which the concepts of bonding and attachment have affected our understanding of appropriate early childcare. 相似文献
53.
The cultural reproduction of lithic technology, long an implicit assumption of archaeological theories, has garnered increasing attention over the past decades. Major debates ranging from the origins of the human culture capacity to the interpretation of spatiotemporal patterning now make explicit reference to social learning mechanisms and cultural evolutionary dynamics. This burgeoning literature has produced important insights and methodological innovations. However, this rapid growth has sometimes led to confusion and controversy due to an under-examination of underlying theoretical and methodological assumptions. The time is thus ripe for a critical assessment of progress in the study of the cultural reproduction of lithic technology. Here we review recent work addressing the evolutionary origins of human culture and the meaning of artifact variation at both intrasite and intersite levels. We propose that further progress will require a more extended and context-specific evolutionary approach to address the complexity of real-world cultural reproduction. 相似文献
54.
Maja Wiprächtiger Melanie Haupt Andreas Froemelt Magdalena Klotz Claudio Beretta Dominik Osterwalder Vanessa Burg Stefanie Hellweg 《Journal of Industrial Ecology》2023,27(1):254-271
Industrial ecology (IE) methodologies, such as input/output or material flow analysis and life cycle assessment (LCA), are often used for the environmental evaluation of circular economy strategies. Up to now, an approach that utilizes these methods in a systematic, integrated framework for a holistic assessment of a geographic region's sustainable circular economy potential has been lacking. The approach developed in this study (IE4CE approach) combines IE methodologies to determine the environmental impact mitigation potential of circular economy strategies for a defined geographic region. The approach foresees five steps. First, input/output analysis helps identify sectors with high environmental impacts. Second, a refined analysis is conducted using material flow and LCA. In step 3, circular strategies are used for scenario design and evaluated in step 4. In step 5, the assessment results are compiled and compared across sectors. The approach was applied to a case study of Switzerland, analyzing 8 sectors and more than 30 scenarios in depth. Carbon capture and storage (CCS) from waste incineration, biogas and cement production, food waste prevention in households, hospitality and production, and the increased recycling of plastics had the highest mitigation potential. Most of the scenarios do not influence each other. One exception is the CCS scenarios: waste avoidance scenarios decrease the reduction potential of CCS. A combination of scenarios from different sectors, including their impact on the CCS scenario potential, led to an environmental impact mitigation potential of 11.9 Mt CO2-eq for 2050, which equals 14% of Switzerland's current consumption-based impacts. 相似文献
55.
During mate choice, receivers often assess the magnitude (duration, size, etc.) of signals that vary along a continuum and reflect variation in signaller quality. It is generally assumed that receivers assess this variation linearly, meaning each difference in signalling trait between signallers results in a commensurate change in receiver response. However, increasing evidence shows receivers can respond to signals non-linearly, for example through Weber's Law of proportional processing, where discrimination between stimuli is based on proportional, rather than absolute, differences in magnitude. We quantified mate preferences of female green swordtail fish, Xiphophorus hellerii, for pairs of males differing in body size. Preferences for larger males were better predicted by the proportional difference between males (proportional processing) than the absolute difference (linear processing). This demonstration of proportional processing of a visual signal implies that receiver perception may be an important mechanism selecting against the evolution of ever-larger signalling traits. 相似文献
56.
Vasil Pirgozliev Stephen C. Mansbridge Izzy M. Whiting Stephen P. Rose Kristina Kljak Amy E. Johnson Falko Drijfhout Sylwia Orczewska-Dudek Atanas G. Atanasov Teodora Mihova 《The Annals of applied biology》2023,183(1):7-14
The aim of this study was to assess the effects of graded levels (0, 3, 6, 9 and 12 g/kg) of dry Sea buckthorn (SB) berries on growth performance, gastrointestinal tract (GIT) development, jejunal histomorphology, bird antioxidant status and caecal short-chain fatty acid concentration when fed to female Ross 308 broiler chickens. In addition, expression of cytokine biomarker genes in the jejunum was evaluated. The five experimental diets were fed from 7 to 21 days age to 8 pens (two birds in each) following randomisation. Feeding SB did not influence bird growth performance (p > .05). There was a linear decrease in butyric, acetic and valeric acid concentrations in caecal digesta (p < .05) and a decrease (p < .05) in crypt depth. The expression of IFNG and CD40LG responded quadratically (p < .05), peaking at 6–9 g/kg dietary inclusion of SB, respectively. Other studied variables were not affected by dietary SB inclusion (p > .05). Feeding dry SB berries up to 12 g/kg of diet did not improve the zootechnical variables of healthy commercial-strain broilers in this study. 相似文献
57.
Alan M. Goldberg John M. Frazier David Brusick Michael S. Dickens Oliver Flint Stephen D. Gettings Richard N. Hill Robert L. Lipnick Kevin J. Renskers June A. Bradlaw Robert A. Scala Bellina Veronesi Sidney Green Neil L. Wilcox Rodger D. Curren 《In vitro cellular & developmental biology. Animal》1993,29(9):688-692
Summary The development and application of in vitro alternatives designed to reduce or replace the use of animals, or to lessen the
distress and discomfort of laboratory animals, is a rapidly developing trend in toxicology. However, at present there is no
formal administrative process to organize, coordinate, or evaluate validation activities. A framework capable of fostering
the validation of new methods is essential for the effective transfer of new technologic developments from the research laboratory
into practical use. This committee has identified four essential validation resources: chemical bank(s), cell and tissue banks,
a data bank, and reference laboratories. The creation of a Scientific Advisory Board composed of experts in the various aspects
and endpoints of toxicity testing, and representing the academic, industrial, and regulatory communities, is recommended.
Test validation acceptance is contingent on broad buy-in by disparate groups in the scientific community—academics, industry,
and government. This is best achieved by early and frequent communication among parties and agreement on common goals. It
is hoped that the creation of a validation infrastructure composed of the elements described in this report will facilitate
scientific acceptance and utilization of alternative methodologies and speed implementation of replacement, reduction, and
refinement alternatives in toxicity testing. 相似文献
58.
Sonia Mannan Jobair Alam K. M. Ashbarul Bari S. M. A. A. Mamun Rehnuma Mehzabin Orin 《Developing world bioethics》2023,23(3):252-259
Informed consent to medical intervention is fundamental in both ethics and law. But in practice it is often not taken seriously in developing countries. This paper provides an appraisal of informed consent practices in Bangladesh. Following a review of the ethical and legal principles of informed consent, it assesses the degree to which doctors adhere to it in Bangladesh. Based on findings of non-compliance, it then investigates the reasons for such non-compliance through an appraisal of informed consent practices in Bangladesh and provides recommendations aimed at improving such practices. The significance of this paper lies in unveiling the interdependence between the ethical and legal traits of informed consent and their ramifications on strengthening the patient-oriented approach of duty to care. 相似文献
59.
Mohiuddin Munawar 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1993,2(2):111-117
Since the 1970's the management of aquatic habitats has changed from piecemeal monitoring to the ecosystem approach; this was initiated in the North American Great Lakes, comprising social, economic, and environmental aspects. The information included in this paper is based on the presentation made at the Seminar On Ecosystem Approach To Water Management held in Oslo, Norway during 1991. Recently, the multidisciplinary, holistic, and integrated concept of ecosystem health has emerged, and is being advanced for the implementation of an ecosystem approach to environmental management, which has resulted in the formation of an international society (Aquatic Ecosystem Health & Management Society) and the publication of a primary journal (Journal of Aquatic Ecosystem Health). The information has been updated to incorporate new developments and recent progress about the Society and the journal since the Oslo Seminar. 相似文献
60.
J. R. Vallentyne M. Munawar 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1993,2(4):231-235
The development of an ecosystem (social, economic, environmental) approach to water management is traced from its origins in the Great Lakes of North America. The focus on health and integrity of ecosystems is an outgrowth of the Lamarckian concept of The Biosphere as a global system of matter, life, and mind. The driving forces behind the development of an ecosystem approach have been negative feedback from excessive demotechnic growth and faith that we can maintain a healthy relationship with Mother Earth. 相似文献