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991.
The reproductive organs of some plants self-heat, release scent, and attract pollinators. The relations among these processes are not well understood, especially in the more ancient, nonflowering gymnosperm lineages. We describe the influence of plant volatiles in an obligate pollination mutualism between an Australian Macrozamia cycad (a gymnosperm with male and female individuals) and its specialist thrips pollinator, Cycadothrips chadwicki. Pollen-laden thrips leave male cycad cones en masse during the daily thermogenic phase, when cone temperatures and volatile emissions increase dramatically and thrips are repelled. As thermogenesis declines, total volatile emissions diminish and cones attract thrips, resulting in pollination of female cones. Behavioral and electrophysiological tests on thrips reveal that variations in b-myrcene and ocimene emissions by male and female cones are sufficient to explain the observed sequential thrips' repellence (push) and attraction (pull). These dynamic interactions represent complex adaptations that enhance the likelihood of pollination and may reflect an intermediate state in the evolution of biotic pollination. 相似文献
992.
Social-ethical issues concerning the control strategy of animal diseases in the European Union: A survey 总被引:1,自引:0,他引:1
Nina E. Cohen Marcel A.P.M. van Asseldonk Elsbeth N. Stassen 《Agriculture and Human Values》2007,24(4):499-510
In 2004 a survey was conducted in the member states of the European Union designed to gain greater insight into the views
on control strategies for foot and mouth disease, classical swine fever, and avian influenza with respect to the epidemiological,
economic and social-ethical consequences of each of these animal diseases. This article presents the results of the social-ethical
survey. A selection of stakeholders from each member state was asked to prioritize issues for the prevention and control of
these diseases. A majority of stakeholders chose preventive measures as the preferred issue. An analysis was done to determine
whether there were differences in views expressed by stakeholders from member states with a history of recent epidemics and
ones without such a history, and whether there were regional differences. There were no differences between member states
with or without a history of recent epidemics. There were indeed regional differences between the priority orders from Northern
and Southern Europe on the one hand, and from Eastern Europe on the other.
Nina
E. Cohen
is a biologist and is a researcher at the Wageningen University. She is specialized in societal and ethical issues in human–animal
relationships. Her current research is focused on the social-ethical issues concerning the prevention and control of foot
and mouth disease, classical swine fever and avian influenza.
Marcel A.P.M. van Asseldonk
has studied animal science. Currently he works at the Institute for Risk Management in Agriculture (IRMA) of the Wageningen
University. He is specialized in the design and pricing of insurance policies and animal health funds for the main livestock
epidemics.
Elsbeth N. Stassen
is a veterinarian and professor of Animals and Society at the Wageningen University. Elsbeth Stassen is specialized in animal
health, animal welfare and human–animal relationships. She was a member of a governmental welfare committee during the avian
influenza epidemic in the Netherlands in 2003. 相似文献
993.
The stratigraphic distribution in Australian Precambrian rocks of columnar stromatolites, organosedimentary structures formed by blue-green algae, has been investigated. Their morphology is being studied according to methods developed in Russia. The discovery of successive different assemblages supports not only regional but also intercontinental stratigraphic correlations which are in agreement with available isotopic datings. 相似文献
994.
The passage of large-sized herpesviral capsids through the nuclear lamina and the inner nuclear membrane to leave the nucleus requires a dissolution of the nuclear lamina. Here, we report on the functions of M50/p35, a beta-herpesviral protein of murine cytomegalovirus. M50/p35 inserts into the inner nuclear membrane and is aggregated by a second viral protein, M53/p38, to form the capsid docking site. M50/p35 recruits the cellular protein kinase C for phosphorylation and dissolution of the nuclear lamina, suggesting that herpesviruses target a critical element of nuclear architecture. 相似文献
995.
996.
Elizabeth Finnis 《Agriculture and Human Values》2007,24(3):343-353
Using a case study from the Kolli Hills, India, I suggest that political ecology provides a useful theoretical basis for considering
localized dietary transitions in rural, agricultural communities in developing countries. By examining the reasons for the
near-disappearance of local minor millets as staple foods in three small-farmer communities, I argue that an explicit, actor-oriented
analysis allows for an integration of food issues with considerations of environmental circumstances, local aspirations, and
labor concerns. That is, an agricultural shift that abandons minor millets as a food resource reflects environmental changes
and household economic aspirations. Such an analysis has implications for the creation of practical food security projects
through the recognition and incorporation of small-farmer experiences, voices, and priorities. This research was undertaken
through ethnographic fieldwork, using semi-structured interviews and participant observation as the primary methods.
Elizabeth
Finnis obtained her PhD from McMaster University in Canada and is currently a post-doctoral fellow in the Department of Anthropology
and the Centre for Society, Technology, and Development at McGill University. 相似文献
997.
Comment on "Emergence of novel color vision in mice engineered to express a human cone photopigment"
Makous W 《Science (New York, N.Y.)》2007,318(5848):196; author reply 196
Jacobs et al. (Reports, 23 March 2007, p. 1723) reported that plasticity in the mammalian visual system permitted the emergence of "a new dimension of sensory experience" in mice genetically engineered to express a human long-wavelength-sensitive cone photopigment. However, neither neural plasticity nor a new dimension of sensory experience is required to explain their results. 相似文献
998.
Kameshwari Pothukuchi Rayman Mohamed David A. Gebben 《Agriculture and Human Values》2008,25(3):319-332
This paper provides a conceptual framework to explain why disparities may exist in food safety code compliance by food stores
in different neighborhoods. Explanations include market dynamics, community characteristics, retailer attributes, inspector
characteristics, and enforcement approaches, and interactions among the factors. A preliminary and limited empirical test
of some of these relationships in Detroit, Michigan shows a higher rate of food safety violations by stores in poorer neighborhoods
and in neighborhoods with higher concentrations of African-American residents. Stores inspected by female inspectors also
scored higher numbers of critical violations, suggesting a need for greater examination of the social relations associated
with enforcement interactions in food safety studies.
Kameshwari Pothukuchi PhD, is Associate Professor of Urban Planning at Wayne State University. She conducts research on issues related to urban food security, including grocery stores, community gardens, and community and regional food planning. A policy guide on community and regional food planning, co-authored by her, was recently adopted by the American Planning Association (). Rayman Mohamed PhD, is Assistant Professor of Urban Planning at Wayne State University. He conducts research on land use and environmental planning. His recent articles examine decision making by developers, the economics of conservation subdivisions, and the relationship between sprawl and the costs of infrastructure. David A. Gebben is a graduate student of agricultural economics and a research assistant in the Global Urban Studies Program at Michigan State University. 相似文献
Kameshwari PothukuchiEmail: |
Kameshwari Pothukuchi PhD, is Associate Professor of Urban Planning at Wayne State University. She conducts research on issues related to urban food security, including grocery stores, community gardens, and community and regional food planning. A policy guide on community and regional food planning, co-authored by her, was recently adopted by the American Planning Association (). Rayman Mohamed PhD, is Assistant Professor of Urban Planning at Wayne State University. He conducts research on land use and environmental planning. His recent articles examine decision making by developers, the economics of conservation subdivisions, and the relationship between sprawl and the costs of infrastructure. David A. Gebben is a graduate student of agricultural economics and a research assistant in the Global Urban Studies Program at Michigan State University. 相似文献
999.
In face of rising flood losses globally, the approach of “living with floods,” rather than relying on structural measures
for flood control and prevention, is acquiring greater resonance in diverse socioeconomic contexts. In the Lerma Valley in
the state of Mexico, rapid industrialization, population growth, and the declining value of agricultural products are driving
livelihood and land use change, exposing increasing numbers of people to flooding. However, data collected in two case studies
of farm communities affected by flooding in 2003 illustrate that the concept of flood as agricultural “hazard” has been relatively
recently constructed through public intervention in river management and disaster compensation. While farming still represents
subsistence value to rural households, increasingly rural communities are relying on non-farm income and alternative livelihood
strategies. In this context, defining flooding in rural areas as a private hazard for which individuals are entitled to public
protection may be counterproductive. A different approach, in which farmers’ long acceptance of periodic flooding is combined
with valuing agricultural land for ecoservices, may enable a more sustainable future for the region’s population.
Hallie Eakin received her doctorate in Geography and Regional Development from the University of Arizona in 2002. She is currently an assistant professor at the University of California, Santa Barbara. As a postdoctoral researcher at the Center of Atmospheric Sciences of the National Autonomous University of Mexico in Mexico City, she continued to work on issues related to economic globalization, agricultural change, and rural vulnerability to climate in the context of several comparative international projects involving case studies in Mexico, Argentina, Guatemala, and Honduras. Her articles on this research have been published in World Development, the Journal of Environment and Development, Climatic Change, Global Environmental Change and Physical Geography. Her book Weathering Risk in Rural Mexico, based on her research on agricultural adaptation to neoliberal reforms and climatic variability in central Mexico, was released by the University of Arizona Press in 2006. Kirsten Appendini has a doctorate in Agricultural Economics from the National Autonomous University of Mexico (UNAM). She currently is a researcher and professor on the faculty of the Center for Economic Studies (Centro de Estudios Económicos) at the Colegio de México in Mexico City. She has published widely on issues of agrarian change, rural poverty, food security, and food policy in Mexico. Her book on Mexican maize policy, De la milpa a los tortibonos: La restructración de la política alimentaria en México (Colmex 2001) is now on its second edition. She has also served as a consultant to the UN Food and Agriculture Organization and several bilateral development agencies. 相似文献
Hallie EakinEmail: |
Hallie Eakin received her doctorate in Geography and Regional Development from the University of Arizona in 2002. She is currently an assistant professor at the University of California, Santa Barbara. As a postdoctoral researcher at the Center of Atmospheric Sciences of the National Autonomous University of Mexico in Mexico City, she continued to work on issues related to economic globalization, agricultural change, and rural vulnerability to climate in the context of several comparative international projects involving case studies in Mexico, Argentina, Guatemala, and Honduras. Her articles on this research have been published in World Development, the Journal of Environment and Development, Climatic Change, Global Environmental Change and Physical Geography. Her book Weathering Risk in Rural Mexico, based on her research on agricultural adaptation to neoliberal reforms and climatic variability in central Mexico, was released by the University of Arizona Press in 2006. Kirsten Appendini has a doctorate in Agricultural Economics from the National Autonomous University of Mexico (UNAM). She currently is a researcher and professor on the faculty of the Center for Economic Studies (Centro de Estudios Económicos) at the Colegio de México in Mexico City. She has published widely on issues of agrarian change, rural poverty, food security, and food policy in Mexico. Her book on Mexican maize policy, De la milpa a los tortibonos: La restructración de la política alimentaria en México (Colmex 2001) is now on its second edition. She has also served as a consultant to the UN Food and Agriculture Organization and several bilateral development agencies. 相似文献
1000.