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21.
This study examines how both strong and weak relationship groups (groups with numerous, intense internal friendship ties and few, less intense internal friendship ties respectively) achieve high performance when utilizing strategies that capitalize on the strengths and minimizing the weaknesses associated with their internal social structure. We examine the interactions of groups' internal friendship networks with their external network structures (external ties) and internal intragroup conflict (constructive controversy). The results of a study using survey, archival and interview data on 35 groups of MBA students indicated that internal friendship networks interacted with constructive controversy and external networks to determine when groups would achieve superior performance. High performing strong relationship groups engaged in greater constructive controversy than low performing strong relationship groups, while constructive controversy appeared to have minimal effect on the performance of weak relationship groups. High performing weak relationship groups had fewer external bridging ties to other groups when compared to low performing weak relationship groups, while external bridging ties appeared to have minimal effect on the performance of strong relationship groups. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
22.
Noise pollution is a significant environmental problem in many rapidly urbanizing areas of Orissa, India. Transportation sector is one of the major contributors to noise in these areas. The present study is an attempt to estimate traffic noise pollution at five places on the way from Vyasa Vihar Campus to Gyan Vigyan Vihar Campus of Fakir Mohan University, Balasore, Orissa. The sources of noise at the studied sites are predominantly attributable to motor vehicular traffic. The noise levels of all the five locations were found to be beyond permissible limit during the day time. The contributions of different types of vehicles to environmental noise were found to ranging from 70.4-94.2, 79.0-96.1, 77.8-110.2, 70.8-90.3, 71.0-87.5, 71.1-84.4, 72.5-86.9 and 74.0-85.4 dB (A) by cargo carrying Trucks, Tractors, Dumpers, Town Buses, Motor cycles, Bolero/Trucker, Pick up and Tempo respectively. The contributions of individual vehicles towards noise pollution were found to be more than the road traffic noise-limit i.e., 70 dB (A). On certain local inhabitants interviewed, the impact of noise was observed in the forms of alterations in their physical, psychological and personal aspects. This study warrants attention from all sections of people to deal with the problem of noise pollution.  相似文献   
23.
Sources of organic matter (OM) in lower Narmada and Tapi river-estuaries were examined using organic carbon to nitrogen ratio (Corg/N), stable carbon isotope ratio (δ13Corg) and lignin phenol biomarkers. The signature of lower Corg (av. 0.50%) and higher δ13Corg (av. –20.3‰) in Narmada and, higher Corg (av. 0.85%) and lower δ13Corg (av. –22.8‰) in Tapi highlight the difference in OM characteristics of both systems, nevertheless they flow adjacent to each other. The OM in Tapi was predominated by fresh plant tissues, as indicated by higher Λ8?=?1.2–3.2?mg/100?mg Corg, lower Ad/Alv?=?0.22–0.46 and lower LPVI?=?17–23. The plant OM present in the sediments of Narmada was previously degraded and mixed with soil. The OM contribution from algae was restricted to estuarine stations in both the rivers, which was ~50% in Narmada and ~35% in Tapi. The contribution of OM from fresh vascular plant was higher (20% to 63%) in Tapi than Narmada (2% to 35%). This study illustrated the benefits of using lignin phenols along with Corg/N and δ13Corg to identify the potential OM sources in two large river–estuary systems of India, which highlighted the complex interaction of natural and anthropogenic processes acted on the terrestrial OM compositions.  相似文献   
24.
Summary The ecological crisis is a result of modern industrial development and its negative impacts which are not conducive to the co-existence of essential diversities in the ecosystem. One of the major trends in present day industry is to move towards computer-based automation. This article discusses the compatibility of this trend towards automation with sustainable development which is regarded as the only viable choice to overcome the ecological crisis. After discussing the present day concepts of sustainable development, automation and the economic impact of automation on society, this paper argues that computer-based automation in industry is not conducive to sustainable development. It is also argued that the spread of automation will decrease the capability of mankind as a whole to implement environmentally sustainable programmes. Finally, the man-nature relationship which is the philosophical basis of the industrial paradigm is discussed. As pointed out by some comparative philosophers, the basic concept of human superiority and separation from nature has to change in order to have a harmonious integrity of life forms as complementary realities in this phenomenal existence.Satyabrata Pradhan is a Post Doctoral Research Fellow of the Department of Mechanical Engineering at the University of British  相似文献   
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26.
Conservation practitioners require strata specific, seasonal species densities for habitat management. Herein, we use stratified distance sampling in Kanha Tiger Reserve (KTR) with 200 spatial transects and an effort of 1200 km walk in the year 2013. Analysis was done to access (a) impact of human use and (b) effect of habitat and season on ungulate densities in KTR. While a single detection function for each species was used for estimating density within human-restricted core and multiple use buffer of KTR, species-specific seasonal detections were modelled for each habitat. Ungulate biomass was 4.8 times higher in the core area compared with the buffer zone. The core supported a herbivore density and biomass of 50 ± 4.80/km2 and 26,806 ± 2573 kg/km2, respectively. Chital were found to be most abundant, having a density of 30.1 ± 4.34/km2 and contributing 33 % of the biomass with a habitat preference for grasslands (106 ± 39/km2) in summer and winter. Sambar had highest density (15.4 ± 3.34/km2) in bamboo-mixed habitat, in both seasons. Gaur contributed 39 % of the ungulate biomass and showed a seasonal shift in density from sal forests (9.65 ± 3.55/km2) in summer to miscellaneous forests (8.13 ± 1.94/km2) in winter. Barasingha were restricted to grasslands with similar summer and winter densities of 1.56 ± 0.76/km2. Chousingha were rare (0.1 ± 0.04/km2), found mostly in miscellaneous forests and plateau grasslands. Grassland and bamboo-mixed forests supported 58 % of the total ungulate biomass. Management for an optimal habitat mosaic that maintains ungulate diversity, addresses the specific needs of endangered species and maximizes ungulate biomass is recommended.  相似文献   
27.
The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent.  相似文献   
28.
• MPs in the coastal sediment of south-east coast of India are quantified. • High MPs are recorded near river mouths and nearshore regions. • Polyethylene and polypropylene are the major polymers observed. • MPs contamination is higher than the values reported elsewhere. In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data, a study was conducted on the abundance, characterization, and seasonal distribution of MPs in the nearshore sediments of the south-east coast of India. Sediment samples (n = 130) were collected at a distance of 1 km and 10 km from the shore region at varying depths (8–45 m) along the Chennai to Puducherry coast (165 km stretch), representing two seasons, i.e., south-west (July 2019 and July 2020) and north-east (January 2020) monsoons. The average abundance of MPs at the 22 offshore sites along the Chennai to Puducherry coast varied from 9±4.3 to 19±12.9 particles/50 g dry weight, in July 2019 and January 2020, respectively. July 2020 had an average abundance of 10±4.5 particles/50 g dry weight. Spatially, high levels of MPs were found at 1km stations and transects in proximity to the river inlets, and temporally, the north-east month recorded the maximum concentration. The dominant morphotype was the filament, and the major polymers were polyethylene and polypropylene. Scanning Electron Microscope (SEM) images revealed the surface irregularity and degradation of MPs due to weathering. The study highlights that high sediment contamination by MPs occurs during heavy rainfall and accumulates closer to river inlets. Eventually, this study suggests that appropriate management of plastic wastes on the landside will reduce MP contamination in the marine environment.  相似文献   
29.
Environmental Science and Pollution Research - The present work encompasses the production of biodiesel from an inexpensive waste, viz., used rice bran oil (URBO) through concurrent esterification...  相似文献   
30.
Fraser syndrome (OMIM 219000) is a rare, autosomal recessive disorder characterized by cryptophthalmos, cutanaeous syndactyly, malformations of the larynx and genitourinary tract, craniofacial dysmorphism, orofacial clefting, mental retardation and musculoskeletal anomalies. There is marked interfamilial clinical heterogeneity. However, there is strong phenotypic similarity and concordance of the degree of severity of the disease within a family. We report a family with two cases of Fraser syndrome with marked clinical heterogeneity. One case had lethal phenotype with bilateral renal agenesis, while the other had mild phenotype with normal kidneys. It has not been reported before and highlights the importance of careful screening of pregnancies in families with Fraser syndrome. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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