太行山羊遗传检测

应用随机整群抽样方法，对太行山羊的两个群体共72只成年羊，用淀粉凝胶电泳法测定了33个血液蛋白座位，并对毛色和外形特征进行了检测。结果表明，运铁蛋白（Tf）、前白蛋白－3（Pa－3）、肽酶－B（Pep-B）、碱性磷酸酶（Alp）、亮氨酸胺肽酶（LAP）和酯酶－D（Es-D)6个血液蛋白座位表现多态性，多态位点比例为0．1818；12个类别 25种外型特征中7个有变异体；4个毛色座位有变异。平均杂合度分析表明，太行山羊变异程度较大（H＝0．555），说明太行山羊群体有效规模较大，目前尚未面临急 待保种的局面.     

PCR技术在蜜蜂疾病诊断中的应用*

 由于蜜蜂疾病的传统诊断方法费时、费力,因此开发快速诊断技术非常重要。分子生物学技术的发展为其提供了可能。笔者对PCR技术在蜜蜂疾病诊断中的应用现状作了综述,并对其中存在的问题和应用前景进行了探讨。     

Carbonate deposition, climate stability, and Neoproterozoic ice ages

The evolutionary success of planktic calcifiers during the Phanerozoic stabilized the climate system by introducing a new mechanism that acts to buffer ocean carbonate-ion concentration: the saturation-dependent preservation of carbonate in sea-floor sediments. Before this, buffering was primarily accomplished by adjustment of shallow-water carbonate deposition to balance oceanic inputs from weathering on land. Neoproterozoic ice ages of near-global extent and multimillion-year duration and the formation of distinctive sedimentary (cap) carbonates can thus be understood in terms of the greater sensitivity of the Precambrian carbon cycle to the loss of shallow-water environments and CO2-climate feedback on ice-sheet growth.     

The political ecology of dietary transitions: Changing production and consumption patterns in the Kolli Hills,India

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.     

Explaining disparities in food safety compliance by food stores: does community matter?

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.

Livelihood change,farming, and managing flood risk in the Lerma Valley,Mexico

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.

How farmers matter in shaping agricultural technologies: social and structural characteristics of wheat growers and wheat varieties

Science and technology studies (STS) research challenges the concept of technological determinism by investigating how the end users of a technology influence that technology’s trajectory. STS critiques of determinism are needed in studies of agricultural technology. However, we contend that focusing on the agency of end users may mask the role of political-economic factors which influence technology developments and applications. This paper seeks to mesh STS insights with political-economic perspectives by accounting for relationships between availability of diverse technologies, variations in political-economic structures, and farmer interests and characteristics. We present the results of an analysis on the recent development of three wheat varieties: (a) a wheat variety that was modified genetically to tolerate the herbicide glyphosate, (b) wheat varieties with characteristics selected to serve specific markets, (c) and emerging research and development of perennial wheat varieties. Using data obtained through a survey of wheat growers in Washington State, we analyzed whether farmer interest in these three clusters of wheat varieties was associated with distinct individual characteristics and attitudes and whether those characteristics and attitudes are consistent with political economic structures. Although our analysis did not allow us to assess the degree of direct influence that farmers have on the technological development trajectory for these types of wheat, we were able to document variation in technological alternatives and farmer characteristics related to different political-economic trends.