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Background

We assessed the health effects of hexavalent chromium groundwater contamination (from tanneries and chrome sulfate manufacturing) in Kanpur, India.

Methods

The health status of residents living in areas with high Cr (VI) groundwater contamination (N = 186) were compared to residents with similar social and demographic features living in communities having no elevated Cr (VI) levels (N = 230). Subjects were recruited at health camps in both the areas. Health status was evaluated with health questionnaires, spirometry and blood hematology measures. Cr (VI) was measured in groundwater samples by diphenylcarbazide reagent method.

Results

Residents from communities with known Cr (VI) contamination had more self-reports of digestive and dermatological disorders and hematological abnormalities. GI distress was reported in 39.2% vs. 17.2% males (AOR = 3.1) and 39.3% vs. 21% females (AOR = 2.44); skin abnormalities in 24.5% vs. 9.2% males (AOR = 3.48) and 25% vs. 4.9% females (AOR = 6.57). Residents from affected communities had greater RBCs (among 30.7% males and 46.1% females), lower MCVs (among 62.8% males) and less platelets (among 68% males and 72% females) than matched controls. There were no differences in leucocytes count and spirometry parameters.

Conclusions

Living in communities with Cr (VI) groundwater is associated with gastrointestinal and dermatological complaints and abnormal hematological function. Limitations of this study include small sample size and the lack of long term follow-up.  相似文献   
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The structure and function of Shisham (Dalbergia sissoo Roxb.) forests were investigated in relation to nutrient dynamics in 5- to 15-year-old stands growing in central Himalaya. Nutrient concentrations and storage in different layers of vegetation were in the order: tree > shrub > herb. Forest soil, litter and vegetation accounted for 80.1-91.9, 1.0-1.5 and 7.0-18.4%, respectively, of the total nutrients in the system. There were considerable reductions (trees 32.8-43.1; shrubs 26.2-32.4; and herbs 18-8-22-2%) in nutrient concentrations of leaves during senescence. Nutrient uptake by the vegetation as a whole and also by the different components, with and without adjustment for internal recycling, was investigated. Annual transfer of litter nutrients to the soil from vegetation was 74.8-108.4 kg ha(-1) year(-1) N, 56.8-4 kg ha(-1) year(-1) P and 38.7-46.9 kg ha(-1) year(-1) K. Turnover rate and time for different nutrients ranged between 56 and 66 % year(-1) and 1.5 and 1.8 years, respectively. The turnover rate of litter indicates that over 50% of nutrients in litter on the forest floor are released, which ultimately enhances the productivity of the forest stand. The nutrient use efficiency in Shisham forests ranged from 136 to 143 kg ha(-1) year(-1) for N, 1,441 to 1,570 kg ha(-1) year(-1) for P and 305 to 311 kg ha(-1) year(-1) for K. Compared with natural oak forest (265 kg ha(-1) year(-1) and an exotic eucalypt plantation (18 kg ha(-1) year(-1), a higher proportion of nutrients was retranslocated in Shisham forests, largely because of higher leaf tissue nutrient concentrations. This indicates a lower nutrient use efficiency of Shisham compared with eucalypt and oak. Compartment models for nutrient dynamics have been developed to represent the distribution of nutrients pools and net annual fluxes within the system.  相似文献   
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Patterns of tree species distribution and their structural-functional features were studied along an altitudinal gradient in the Indian Central Himalaya. The forest vegetation falls within three formation types: low to mid-montane sclerophyllous, broad-leaved forests; mid-montane deciduous forests; and high-montane mixed stunted forests. Deciduous tree species formed a considerable (49%) portion of the high altitude forests between 1500–3300 m. The upper limit of forests ranges from 3000 to 3300 m, and three taxa are commonly found at tree line: an evergreen, needle-leaved gymnosperm (Abies pindrow Spach.), an evergreen, broad-leaved sclerophyllous oak (Quercus semecarpifolia Sm.), and a deciduous, broad-leaved birch (Betula utilis Don).The high altitude forests differed from the low altitude forests of Central Himalaya in their greater proportion of microphanerophytes. Vernal flowering is common at this elevation in Central Himalaya. In general, in their elevational distribution and structural-functional attributes, these high altitude forests are similar to other forests of cool temperate zones in Himalaya.  相似文献   
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A total of 105 climber species were recorded and studied for their altitudinal distribution and phenology. Relatively higher percentage (54%) of deciduous species was recorded. In general, the climbers were distributed throughout the region between altitudes of 300–3500 m. However, maximum (more than 60%) species were confined either below or at around 1500 m altitude. Species richness declines gradually towards the higher altitudes, the decline was more sharp in evergreen species. The different phenological activities were usually governed by the seasonal variations in a year. Seasonality of flowering suggested the prevalence of insect pollination. Whereas, fruit types indicated equal sharing of biotic and abiotic dispersal. Study concludes, the distribution and nature of various climber species of Kumaun in Indian Central Himalaya, depends largely upon altitude and its climatic variable temperature. Whereas, the seasonality of rains plays an important role in seasonal progression of phenophases.  相似文献   
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Phenology of high-altitude plants of Kumaun in Central Himalaya,India   总被引:1,自引:0,他引:1  
The various developmental stages of 184 species of high-altitude plants were studied during 1987 and 1988 in the Pindari glacial moraine area of Kumaun Himalaya in the Central Himalaya. The initiation of growth was synchronised with the beginning of the spring/or summer temperature rise and snowmelt. In this high-altitude zone, the peaks of various phenophases succeeded one after another over about 4 months from early June to October. It is suggested that the plants complete various growth cycles within a very short period of favourable conditions to ensure the survival of their progeny.  相似文献   
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Aquaporins (AQP) 1, 2, 3 and 4 belong to the aquaporin water channel family and play an important role in urine concentration by reabsorption of water from renal tubule fluid. Renal AQPs have not been reported in the yak (Bos grunniens), which resides in the Qinghai Tibetan Plateau. We investigated AQPs 1?4 expressions in the kidneys of Yak using immunohistochemical staining. AQP1 was expressed mainly in the basolateral and apical membranes of the proximal tubules and descending thin limb of the loop of Henle. AQP2 was detected in the apical plasma membranes of collecting ducts and distal convoluted tubules. AQP3 was located in the proximal tubule, distal tubule and collecting ducts. AQP4 was located in the collecting ducts, distal straight tubule, glomerular capillaries and peritubular capillaries. The expression pattern of AQPs 1?4 in kidney of yak was different from other species, which possibly is related to kidney function in a high altitude environment.  相似文献   
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Background

Global Burden of Disease Study 2010 demonstrates the impact of musculoskeletal diseases as the second greatest cause of disability globally in all regions of the world. The study was conducted to determine the role of mathematically derived body volume (BV), body volume index (BVI), body mass index (BMI), body surface area (BSA) and body fat % (BF %) on musculoskeletal pain (MSP) among housewives in National Capital Region (NCR).

Methods

A cross sectional study was undertaken among 495 housewives from Gurgaon and New Okhla Industrial Development Area (NOIDA) in National Capital Region (NCR), New Delhi, India. The study includes questionnaire survey, clinical examination and body composition monitoring among housewives.

Results

A significantly higher BMI, BVI, BV and BSA were observed in subjects with MSP as compared to those who had no MSP. This was also true for subjects with pain in knee for BMI category for overweight. Subjects with pain in limbs had significantly high BMI and BVI as compared to subjects with no MSP. A significant positive correlation of age with BMI, BVI, BV and BSA was observed among subjects having no MSP denoting a direct relationship of age and these body factors.

Conclusions

The prevalence of MSP among housewives is associated with increasing age, BMI and BVI. This can possibly be used for formulating a strategy for prevention of MSP.  相似文献   
10.
The biomass and net primary productivity (NPP) of 5- to 15-year-old Shisham (Dalbergia sissoo Roxb.) forests growing in central Himalaya were estimated. Allometric equations were developed for all above- and below-ground components of trees and shrubs for each stand. Understorey forest floor biomass and litter fall were also estimated in forest stands. The biomass (dry matter), forest floor biomass (standing crop litter), tree litter fall and NPP of trees and shrubs increased with increasing age of the forest stand, whereas the dry matter and herb NPP decreased significantly (P < 0.001) with increasing age of the forest. Total forest biomass and NPP ranged from 58.7 (5-year-old stand) to 136.1 t ha(-1) (15-year-old stand) and 12.6 (5-year-old stand) to 20.3 t ha(-1) year(-1) (15-year-old stand), respectively. Of these values, tree biomass accounted for 85.7 (5-year-old stand) to 90.1% (15-year-old) of total forest biomass, and tree NPP for 72.2 (5-year-old) to 82.3% (15-year-old) of total forest NPP. The biomass accumulation ratio (BAR) of the bole component (bole wood + bole bark) increased with increasing age of the forest stand. The bole BAR was 5.8 (5-year-old stand) to 7.9 (15-year-old stand). However, total BAR of the forest stand ranged from 5.5 (5-year-old) to 7.5 (15-year-old).  相似文献   
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