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Obesity and diabetes are increasingly attributed to environmental factors, however, little attention has been paid to the influence of the ‘local’ food economy. This paper examines the association of measures relating to the built environment and ‘local’ agriculture with U.S. county-level prevalence of obesity and diabetes. Key indicators of the ‘local’ food economy include the density of farmers’ markets and the presence of farms with direct sales. This paper employs a robust regression estimator to account for non-normality of the data and to accommodate outliers. Overall, the built environment is associated with the prevalence of obesity and diabetes and a strong local’ food economy may play an important role in prevention. Results imply considerable scope for community-level interventions.  相似文献   

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The small brown planthopper, Laodelphax striatellus, is one of the most serious pest insects of rice plants. A large migration of the insects from overseas was reported in western parts of Japan in June 2008. Insecticide resistance to imidacloprid, fipronil and BPMC was compared among local populations in these western regions after migration. The insecticides were applied to the insects using a topical application method. In some populations, the resistance status coincided with that of the immigrant insects just after migration, i.e., resistance to imidacloprid but susceptibility to fipronil. In other populations, resistance was observed not only against imidacloprid but also fipronil. It is likely that the status of the latter populations resulted from intercrossing between domestic populations of the insects and migrants. Insecticide resistance was also assessed in other areas of northern and eastern parts of Japan. In general, these populations showed relatively low resistance, although resistance to fipronil was high in the eastern part of Japan where the density of domestic populations has recently increased. Insecticide susceptibilities were also assessed in several sites in Taiwan and the northern parts of Vietnam. Although susceptibilities differed among these sites or countries, they have recently seen a decline for all three insecticides.  相似文献   

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The first reports of wild caught Australian redclaw crayfish from Mexico, in the states of Morelos and Tamaulipas, are presented. Redclaw crayfish were first brought to Mexico in 1995 to initiate experimental cultures at several research centers. In the following years a number of private ventures started commercial cultures, several of which in the states of Morelos and Tamaulipas are thought to have been the sources for the wild populations recorded in this study. The farms that acted as the original sources have not been operating for at least 2 years. In Morelos, high densities and all size classes of redclaws, including ovigerous females, were captured in natural waterways; whereas in Tamaulipas they were found at four sites occurring in irrigation canals in an agricultural district. The size attained by the wild redclaws, the abiotic conditions in which they were found and the potential for spread within the drainage systems of the Balsas and Tamesi Rivers are discussed.  相似文献   

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This study aimed to investigate the effects of selenium on the ion profiles in the heart, liver, spleen, and kidney through the oral administration of hexavalent chromium. Approximately 22.14 mg/kg b.w. K2Cr2O7 was added to water to establish a chronic poisoning model. Different selenium levels (0.00, 0.31, 0.63, 1.25, 2.50, and 5.00 mg Na2SeO3/kg b.w.) around the safe dose were administered to the experimental group model. Ca, Mg, Mn, Fe, Cu, and Zn were detected in the organs through flame atomic absorption spectrometry after these organs were exposed to K2Cr2O7 and Na2SeO3 for 14, 28, and 42 days. Results showed that these elements exhibited various changes. Ca contents declined in the heart, liver, and spleen. Ca contents also decreased on the 28th day and increased on the 42nd day in the kidney. Mn contents declined in the heart and spleen but increased in the kidney. Mn contents also decreased on the 28th day and increased on the 42nd day in the liver. Cu contents declined in the heart and spleen. Cu contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Zn contents declined in the heart and spleen. Zn contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Fe contents decreased in the heart and liver. Fe contents increased on the 28th day and decreased on the 42nd day in the spleen and kidney. Mg contents did not significantly change in these organs. Appropriate selenium contents enhanced Mn and Zn contents, which were declined by chromium. Conversely, appropriate selenium contents reduced Ca, Fe, and Cu contents, which were increased by chromium. In conclusion, the exposure of chickens to K2Cr2O7 induced changes in different trace elements, and Na2SeO3 supplementation could alleviate this condition.  相似文献   

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Abstract: The regional distributions of the G protein β subunits (Gβ1–β5) and of the Gγ3 subunit were examined by immunohistochemical methods in the adult rat brain. In general, the Gβ and Gγ3 subunits were widely distributed throughout the brain, with most regions containing several Gβ subunits within their neuronal networks. The olfactory bulb, neocortex, hippocampus, striatum, thalamus, cerebellum, and brainstem exhibited light to intense Gβ immunostaining. Negative immunostaining was observed in cortical layer I for Gβ1 and layer IV for Gβ4. The hippocampal dentate granular and CA1–CA3 pyramidal cells displayed little or no positive immunostaining for Gβ2 or Gβ4. No anti-Gβ4 immunostaining was observed in the pars compacta of the substantia nigra or in the cerebellar granule cell layer and Purkinje cells. Immunoreactivity for Gβ1 was absent from the cerebellar molecular layer, and Gβ2 was not detected in the Purkinje cells. No positive Gγ3 immunoreactivity was observed in the lateral habenula, lateral septal nucleus, or Purkinje cells. Double-fluorescence immunostaining with anti-Gγ3 antibody and individual anti-Gβ1–β5 antibodies displayed regional selectivity with Gβ1 (cortical layers V–VI) and Gβ2 (cortical layer I). In conclusion, despite the widespread overlapping distributions of Gβ1–β5 with Gγ3, specific dimeric associations in situ were observed within discrete brain regions.  相似文献   

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Leaf surface preference of the cabbage worm, Pieris rapae crucivora Boisduval (Lepidoptera: Pieridae), for cabbage, Brassica oleracea L. var. capitata (Brassicaceae), and parasitism by the parasitoid Cotesia glomerata (L.) (Hymenoptera: Braconidae) were investigated experimentally in the laboratory. Female butterflies did not discriminate between the adaxial and abaxial surfaces of cabbage leaves when laying eggs on a vertically placed leaf. Larvae also did not discriminate between the adaxial and abaxial surfaces throughout their larval life. However, second and third instars preferred the lower surface of horizontally placed leaves to the upper surface, irrespective of whether they had hatched on the upper or lower side; other instars showed no preference for the lower surface. Parasitism rates of first and second instars on the upper surface were higher than those of larvae on the lower surface. Egg distribution on leaf surfaces and the leaf surface preference by young larvae are discussed in terms of avoidance of parasitism by the parasitoid C. glomerata.  相似文献   

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Otolith microstructure of Oxygymnocypris stewartii collected from the Lhasa River was examined and described with regards to the early life history events. The monthly changes in the number of microincrements on the margin of the otolith were examined to validate the approximately daily periodicity of otolith increment formation. The microstructure of otoliths was used to detect changes in microincrement deposition patterns corresponding with events during early life. The annuli, microincrements and checks including the hatch check, yolk absorption check and several recurrent patterns in the otolith were described. Periodicity of the recurrent patterns was weekly, fortnightly and monthly. Through counting the number of the microincrements, it was confirmed that the primary growth of O. stewartii was in a period of 7 or 8 months from late March to October; it was estimated that O. stewartii might hatch between April and May.  相似文献   

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The current study presents phenology data for Rhizophora mangle from two equatorial mangrove stands with different salinity regimes in Brazil. Observations based on litter fall and individual shoot development were compared and related to environmental factors. Patterns observed in litter fall were consistent with results of direct monitoring. While both reproductive organs and leaves were produced throughout the year, rates of formation followed seasonal trends. Distinct differences in propagule production between low and high salinity sites and between years of observation were detected; main propagule release was, however, restricted to the wet season which offers enhanced conditions for propagule establishment. Emergence of flowers was linked to leaf production. While there was no obvious single peak in leaf production, it was reduced towards the end of the dry season at both high and low salinity sites. Time series analysis revealed an independent pattern of leaf development superimposed on this annual seasonal trend, indicating slower development of leaf primordia during periods of low light availability in the wet season. No significant difference in age structure was detected between sun and shade leaves; maximum leaf life-time was approximately 1 year.  相似文献   

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The article describes the documentary vicissitudes of young Gambian men of Soninke ethnicity. Normally the most mobile subjects in a milieu where international migration is central to subsistence and prosperity, these young men often fail to secure entry visas to the West and other desirable destinations owing to restrictive admission policies. Would‐be travellers cope with high rejection rates, but also struggle to secure financial and logistical support from relatives in order to meet the demanding requirements of visa applications. Since kinship mediates access to travel documents, the article suggests that visa ineligibility is a product of both state‐based and societal practices of certification. It shows how the visa regime plays into the kinship reciprocities and affects that produce, discipline, and select prospective migrants, thereby transferring and concealing the arbitrariness and uncertainty of legal‐political structures of mobility.  相似文献   

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Stocks of fixed capital play a vital role in fulfilling basic human needs and facilitating industrial production. Their build‐up requires great quantities of energy and materials, and generates greenhouse gas emissions and other pollution. Capital stocks influence economic production and environmental pollution through their construction and over subsequent decades through their use. We perform an environmental footprint analysis of total consumption, capital investment, and capital consumption in the United States for 2007 and 2012. In 2012, capital consumption accounted for 13%, 19%, and 40% of total carbon, energy, and material footprints, respectively. Housing, federal defense, state and local government education and other services (including household consumption of roads), personal transport fuels, and hospitals are the consumption sectors with largest capital footprints. These sectors provide fundamental needs of shelter, transport, education, and health, underlying the importance of capital services. Endogenizing capital causes the biggest proportional increase to footprints of sectors with low environmental multipliers. This work builds upon existing input‐output models of production and consumption in the United States, and provides a capital‐inclusive database of carbon, energy, and material footprints and multipliers for 2007 and 2012. This article met the requirements for a gold – gold JIE data openness badge described at http://jie.click/badges .  相似文献   

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The caterpillar mushroom Ophiocordyceps sinensis (syn. Cordyceps sinensis) is among the most valuable mushrooms in the world, and plays a major role for the local economies in its distribution area on the Tibetan Plateau and adjacent regions. Large proportions of its habitat fall into protected areas, and best practice of sustainable harvest is under discussion, considering both, O. sinensis as a valuable income source for rural poor and protection of its populations and habitat. This study aims for a detailed analysis of O. sinensis collection in a nature reserve in Southwest China. We found that harvesting is unevenly distributed among households and villages, with households who have access to the resource but lack adequate alternatives for income generation such as rewarding wage labor, fertile agricultural fields or harvest of other high value products being most involved. Although collection is de jure forbidden, authorities of the nature reserve apply adaptive management strategies for sustainable resource use. This includes the allocation of collection areas to communities based on their traditional land use strategies and the control of harvesters from outside, triggering self-policing of the resource by the local people. The strategies applied provide a promising model also for other protected areas where the caterpillar mushroom is collected.  相似文献   

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Poaching and habitat destruction across sub-Saharan Africa brought the black rhinoceros (Diceros bicornis) close to extinction. Over the past few decades, however, one of four subspecies, D. b. bicornis, has experienced a significant population increase as a consequence of its protection within Etosha National Park (ENP), Namibia. We report here on the level and spatial distribution of black rhinoceros genetic diversity within ENP. Using nine microsatellite loci, genetic variation was assessed from 144 individuals. Our results are consistent with the observation of lower levels of genetic diversity in D. b. bicornis, when compared to D. b. michaeli, but greater diversity when compared to D. b. minor. We also showed that ENP’s black rhino genetic diversity is well represented in Waterberg National Park, originally founded with ENP individuals. We found no genetic signature of a recent bottleneck in ENP, however, suggesting that the genetic diversity within ENP has not been adversely affected by the recent severe population decline. Using Bayesian clustering methods, we observed no significant population structure within ENP, but positive spatial genetic correlation is observed at distances up to 25 km. This relationship exists in females but not males, suggesting reduced dispersal among females, the first evidence of limited female dispersal or philopatry in any species of rhinoceros.  相似文献   

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We assessed the population status of endangered lion-tailed macaques (Macaca silenus) in the rain forests of Kudremukh Forest complex (Kudremukh National Park, Someshwara Wildlife Sanctuary and Mookambika Wildlife Sanctuary), Western Ghats, Karnataka in January 2007. We performed a census of 20 groups in Kudremukh NP, 4 groups in Someshwara WS, and 6 groups in Mookambika WS. We estimated the population size as ca. 451 individuals in the 3 parks. The forests of Kudremukh NP and Someshwara WS are continuous, and the present finding of 24 groups in a single continuous forest confirms the existence of another significant population of lion-tailed macaques.  相似文献   

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