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991.
Embodiment is a central concept in Krieger’s ecosocial theory, and is said to be of relevance to the understanding of the relationship between social conditions and a variety of adverse health outcomes. The most detailed empirical investigation of this in Krieger’s work is to be found in her studies of the relationship between racial discrimination and high blood pressure. Of especial relevance here is the idea of internalized oppression which is said to explain the observed association between self-reports of no racial discrimination and increased levels of blood pressure among working-class African Americans. Here we critically examine the empirical evidence pertaining to internalized oppression. Specifically, we focus on the measurement of the construct and the quality of the empirical evidence that has been presented in support of the hypothesis that there is an association between internalized oppression and adverse health outcomes. We argue that the validity of the concept has yet to be established and that the available data linking it to poor health outcomes are open to alternative explanations, notably measurement error and misclassification.
Eugenia CondeEmail:
  相似文献   
992.
993.
Utilizing geographic information systems (GIS) and statistics, objectives of this study were to evaluate: (a) the spatial distribution of nitrate concentrations in groundwater, and (b) associations between nitrate concentrations and: proximity to playa lakes, hydraulic conductivity of soil, well depth, and land use in the High Plains Aquifer, Texas. Data were compiled from wells sampled during 2000–2008. Nitrate concentrations in approximately 9% of wells exceeded the maximum contaminant level for drinking water. Concentrations were generally higher beneath urban and agricultural land, under permeable soil, and in shallow wells (especially in the southern part of the study area). However, concentrations were lower near playa lakes. While playas focus recharge to groundwater, denitrification in reducing environments lower nitrate concentrations beneath them. This study identifies areas vulnerable to nitrate contamination that warrant continued monitoring and mitigation efforts.  相似文献   
994.
To understand and predict the role of soils in changes in alpine meadow ecosystems during climate warming, soil monoliths, extending from the surface to the deepest roots, were collected from Carex moorcroftii, Kobresia humilis, mixed grass, and Kobresia pygmaea alpine meadows in the hinterland of the Tibetan Plateau, China. The monoliths were used to measure the distribution with depth of biomass, soil grain size, soil nutrient levels, and soil moisture. With the exception of the K. pygmaea meadow, the percentages of gravel and coarse sand in the soils were high, ranging from 37.7 to 57.8% for gravel, and from 18.7 to 27.9% for coarse sand. The texture was finest in the upper 10 cm soil layer, and generally became coarser with increasing depth. Soil nutrients were concentrated in the top 15 cm soil layer, especially in the top 10 cm. Soil water content was low, ranging from 3 to 28.4%. Most of the subsurface biomass was in the top 10 cm, with concentrations of 79.8% in the K. humilis meadow, 77.6% in the mixed grass meadow, and 62.3% in the C. moorcroftii meadow. Owing to deeper root penetration, the concentration of subsurface biomass in the upper 10 cm of K. pygmaea soil was only 41.7%. The subsurface biomass content decreased exponentially with depth; this is attributed to the increase in grain size and decrease in soil nutrient levels with depth. Soil water is not a primary factor influencing the vertical and spatial distribution of subsurface biomass in the study area. The lack of fine material and of soil nutrients resulted in low surficial and subsurface biomass everywhere.  相似文献   
995.
This study examines shelter effect against the wind by using wind fence with various porosities and distance. The shelter effect of wind fence was investigated by a wind tunnel test. Flow characteristics of velocities and turbulences behind wind fence were measured using a hot-wire anemometer. This was done by varying the porosity by 0, 20, and 40% of the wind fence. The wind fence distance ranged from 1H to 9H. In addition, the overall characterization of the wind fence was investigated by measuring a total of 28 points on the wind fence, which forms a lattice structure on it with 7 points in the lateral direction and 4 points in the vertical direction. The results indicate that the degree of the turbulence is lowered and the velocity of the wind is decreased when porosity of 40% is used at a distance of 4H–7H. The effectiveness of the wind fence depends on the porosity and distance. Porosity of 20% proved to be effective for the protection area of 1H–3H, while that of 40% was effective for the protection area of 4H–6H.  相似文献   
996.
Based on investigations of the Zhongwei Nanshan aeolian section situated in the southeastern margin of Tengger Dcsert, carbon-14 and TL (thermoluminescence) dating results and paleoclimatic proxies such as magnetic susceptibility and grain size, we inferred that the northwestern margin of East Asian monsoon region experienced abrupt climatic changes during the last deglaciation. Six oscillation events were identified: Oldest Dryas, Belling, Older Dryas, AllerФd, lntra-AllerФd Cold Period (1ACP) and Younger Dryas (YD). The summer monsoon was weaker during Oldest Dryas and Younger Dryas when the winter monsoon was stronger. However, during the B/A (BФlling/AllerФd) period, the summer monsoon strengthened, reflected by magnetic susceptibility, when the winter monsoon also became strong, which is different from the paleoclimatic pattern established in the East Asian monsoon region. Furthermore,the summer monsoon was nearly in phase with the climate changes inferred from the oxygen isotopic records of Greenland ice cores. It could be speculated that the variations of the sea ice cover in the high latitudes of the North Hemisphere affected the high pressure of Asian continent and the changes of the winter monsoon inland. On the other hand,the sea ice cover variations might have indirectly caused the occurrence of ENSO events that has tightly been related to the summer monsoon in northwest margin of East Asian monsoon region.  相似文献   
997.
Hong Kong is a hyper-dense city with 7×106 people living in an area of 1100km2. One way to improve the livability of compacted and congested cities like Hong Kong is through the provision of urban parks, an aspect that has largely been under-researched. This study focuses on how users perceive and utilize various facilities in the Kowloon Park. The findings revealed that the Kowloon Park is one of the most preferred parks in Hong Kong for both local residents and tourists. Users were quite satisfied with the park’s facilities. Notably, the most important component of an urban park is its greenery. This is followed by water elements, seating places, and facilities for various recreational activities. The improvements users would like to see in urban parks include good design and management, meeting users’ needs, overcoming barriers to use, and providing a high quality and varied experience for different groups in the community. The findings of this study provide a good basis to address park management issues from the users’ perspective. In particular, parks should provide easy access, encourage optimum usage and enable complimentary improvements to the environment. Foundation item: Under the auspices of the Germany-Hong Kong Joint Research Scheme (No.GER/99-00/01) and the Faculty Research Grant of the Hong Kong Baptist University (No.FRG/00-01/I-38) Biography: WONG Koon-kwai (1950—), male, a native of Guangdong Province, Ph.D., associate professor, specialized in the analysis of human-environment interaction. E-mail: kenwong@hkbu.edu.hk  相似文献   
998.
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper “How long is the coastline of Britain?” published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method, the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China‘s Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China‘s Mainland, and it does not vary with the changes of series of square grids, the fractal dimensions of the mountains of China‘s Mainland are different with these changes. 2) The fractal dimensions of the mountains of China‘s Mainlandvary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China‘s Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension, and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China‘s Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China‘ s Mainland. The research is helpful to get the more understanding of fractal and fractal dimension, and ensure that the fractal studies would be scientific.  相似文献   
999.
This study examined the thermal effects of building‘s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external surface. Results indicate that external wall surface temperature and nearby air temperature vary with the change of orientation, height and season. In general, the external wall surface temperature is lower near the ground, and is higher near the roof, than nearby air temperature. But north wall surface temperature is mostly lower than nearby air temperature at the same height; south wall surface temperature during the daytime in December, and west wall surface temperature all day in August, is respectively higher than nearby air temperature. The heat fluxes into and out of external wall surfaces show the differences that exist in the various orientations, heights and seasons. In December,south wall surface at the lower sites emits heat and north wall surface at the higher sites absorbs heat. In April, all external wall surfaces, emit heat near the ground and absorb heat near the roof. In August, west wall surface all day emits heat, and other wall surfaces just show the commensurate behavior with that in April.  相似文献   
1000.
Coral microatoll as geodetic tool in North Andaman and Little Andaman,India   总被引:1,自引:0,他引:1  
Coral microatolls were examined from North Andaman and Little Andaman to understand the relative sea level change due to vertical tectonic deformation above the subduction interface. The highest level of survival of coral microatoll before the 26 December, 2004 earthquake at eastern coast of North Andaman has been determined by Global Ocean Tide Model. The present position of recently dead flat top microatoll with preserved internal structure at the eastern coast of North Andaman mainland indicates 31.21 cm uplift due to the 26 December, 2004 earthquake. Comparatively old cup shaped microatoll at the eastern fringe of North Andaman group of islands and highly bioeroded fossil microatolls at the intertidal zone of Little Andaman bear the signature of permanent vertical deformation in the past.  相似文献   
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