397 research outputs found

    A Chain Oriented Data Collection Protocol for Energy-Aware and Delay-Constrained WSN

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    Energy awareness plays an important role in developing routing protocol for the battery powered wireless sensor networks. As the replacement of the battery is often unfeasible in practical situations, we present here an optimal solution for the maximum utilization of precious available energy at the same time trying to minimize the latency in data delivery. We propose to form hierarchical chains with deployed sensors to collect information from a target field where data get fused at every node level before transmitted finally. Our protocol utilizes the higher energy nodes for more frequent long distance transmissions so that the energy expenditure become even between all nodes in the network irrespective of their physical locations. It has been found in our simulation that this protocol outperforms other hierarchical protocols like LEACH and PEGASIS in both the cases of energy consumption and time requirements respectively. It has been also found that the overall lifetime of the sensor network also increases in our protocol

    Surgico-therapeutic management of thoroughpin in two Camels (Camelus dromedarius)

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    Abstract Tenosynovitis of the tarsal sheath is called thoroughpin of tarsal sheath. It is common in horses but in present report it is found in two camels. One camel respond to injection of corticosteroid into the cavity of the tarsal sheath but other did not, therefore surgical approach was determined. There was a remarkable improvement in the swelling as well as degree of lameness after surgery

    A CASE STUDY ON GAS RECOVERY UNIT FOR R-22

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    The present research is concerned with proper recovery of the R-22 [1] gas, which is widely used in various R.A.C. fields on the system failure and reusing these recovered gases again for the future use. It is well known that various cooling units are widely spread in their applications and are circulating R-22 as a refrigerant. It is intended to recover this type of refrigerant by any means preventing its ill effects on environment. The time required for recovering is less, hence the system requires less time. The recovery rate of the unit ranges between 1 to 2 kg/min for 1 ton capacity of the system. We can use the unit for any ton capacity of the breakdown system refrigeration and air conditioning system to recover the gas. The. Global warming [2] is the process wherein the average temperature of the Earth\u27s near surface air increases, owing largely to various man-made activities. Though there are some natural causes for this rise in temperature, they stand to be insignificant when compared to the man-made causes. Understanding global warming & green house gas causes and effects can give us a brief idea of the dreadful phenomena our future generations may have to face. There are some of the prominent global warming causes and effects

    Avaliação dos pacotes bibliográficos do serviço automatizado de Disseminação Seletiva da Informação da Empresa Brasileira de Pesquisa Agropecuária: SDI/Embrapa

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    O SDI/EMBRAPA, estabelecido com base na automação, facilita aos pesquisadores a obtenção mensal de informa­ção. Os materiais utilizados na avaliação variam segundo o tipo de abordagem. Os resultados e análise baseiam-se na avaliação quantitativa, qualitativa e estatística bibliográ­fica

    Tailoring the dispersibility of non-covalent functionalized multi-walled carbon nanotube (MWCNT) nanosuspension using shellac (SL) bio-resin: Structure-property relationship and cytotoxicity of shellac coated carbon nanotubes (SLCNTs)

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    This study first reports the use of natural thermoplastic bio-resin shellac (SL) to functionalize multi-walled carbon nanotubes (MWCNTs). The MWCNTs were coated with 5, 10, and 15 wt% SL solutions to fabricate SLCNT nanocomposites which are highly dispersible and stable in solution. Enhanced surface charge imparted long-term stabilization of SLCNT nanosuspension. Microscopic analysis revealed distinct dispersion of nanotubes and a thin layer of SL on the surface of nanotubes in the nanocomposite system. FTIR and Raman spectroscopy confirmed well interaction between SL and MWCNT in the nanocomposites. It was disclosed by the microstructure analysis that the SL concentration affects the lattice parameters of SLCNT nanocomposites. The thermal stability of SLCNT was impressive compared to MWCNT. According to the ROS (reactive oxygen species) generation profile and cell viability study, SLCNTs have reduced adverse effects on cells. Therefore, the results confirm that shellac can significantly improve the stability of MWCNT and reduce the cytotoxicity to facilitate their widespread applications

    Determinants of Managerial Values on Corporate Social Responsibility: Evidence from China

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    This paper empirically investigates how Chinese executives and managers perceive and interpret corporate social responsibility (CSR), to what extent firms’ productive characteristics influence managers’ attitudes towards their CSR rating, and whether their values in favour of CSR are positively correlated to firms’ economic performance. Although a large proportion of respondents express a favourable view of CSR and a willingness to participate in socially responsible activities, we find that the true nature of their assertion is linked to entrepreneurs’ instincts of gaining economic benefits. It is the poorly-performing firms, or rather, firms with vulnerable indicators – smaller in size, State-owned, producing traditional goods and located in poorer regions that are more likely to have managers who opt for a higher CSR rating. Managers’ personal characteristics per se are not significant in determining their CSR choice. Moreover, controlling for other observed variables, we find that managers’ CSR orientation is positively correlated with their firms’ performance. The better-off a firm is, the more likely its manager is to get involve in CSR activities. Firms with better economic performance before their restructuring would sustain higher post-restructuring performance

    Trends in prevalence of blindness and distance and near vision impairment over 30 years: an analysis for the Global Burden of Disease Study

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    Background To contribute to the WHO initiative, VISION 2020: The Right to Sight, an assessment of global vision impairment in 2020 and temporal change is needed. We aimed to extensively update estimates of global vision loss burden, presenting estimates for 2020, temporal change over three decades between 1990–2020, and forecasts for 2050. Methods We did a systematic review and meta-analysis of population-based surveys of eye disease from January, 1980, to October, 2018. Only studies with samples representative of the population and with clearly defined visual acuity testing protocols were included. We fitted hierarchical models to estimate 2020 prevalence (with 95% uncertainty intervals [UIs]) of mild vision impairment (presenting visual acuity ≥6/18 and <6/12), moderate and severe vision impairment (<6/18 to 3/60), and blindness (<3/60 or less than 10° visual field around central fixation); and vision impairment from uncorrected presbyopia (presenting near vision <N6 or <N8 at 40 cm where best-corrected distance visual acuity is ≥6/12). We forecast estimates of vision loss up to 2050. Findings In 2020, an estimated 43·3 million (95% UI 37·6–48·4) people were blind, of whom 23·9 million (55%; 20·8–26·8) were estimated to be female. We estimated 295 million (267–325) people to have moderate and severe vision impairment, of whom 163 million (55%; 147–179) were female; 258 million (233–285) to have mild vision impairment, of whom 142 million (55%; 128–157) were female; and 510 million (371–667) to have visual impairment from uncorrected presbyopia, of whom 280 million (55%; 205–365) were female. Globally, between 1990 and 2020, among adults aged 50 years or older, age-standardised prevalence of blindness decreased by 28·5% (–29·4 to −27·7) and prevalence of mild vision impairment decreased slightly (–0·3%, −0·8 to −0·2), whereas prevalence of moderate and severe vision impairment increased slightly (2·5%, 1·9 to 3·2; insufficient data were available to calculate this statistic for vision impairment from uncorrected presbyopia). In this period, the number of people who were blind increased by 50·6% (47·8 to 53·4) and the number with moderate and severe vision impairment increased by 91·7% (87·6 to 95·8). By 2050, we predict 61·0 million (52·9 to 69·3) people will be blind, 474 million (428 to 518) will have moderate and severe vision impairment, 360 million (322 to 400) will have mild vision impairment, and 866 million (629 to 1150) will have uncorrected presbyopia. Interpretation Age-adjusted prevalence of blindness has reduced over the past three decades, yet due to population growth, progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages

    Mapping development and health effects of cooking with solid fuels in low-income and middle-income countries, 2000–18: a geospatial modelling study

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    Background: More than 3 billion people do not have access to clean energy and primarily use solid fuels to cook. Use of solid fuels generates household air pollution, which was associated with more than 2 million deaths in 2019. Although local patterns in cooking vary systematically, subnational trends in use of solid fuels have yet to be comprehensively analysed. We estimated the prevalence of solid-fuel use with high spatial resolution to explore subnational inequalities, assess local progress, and assess the effects on health in low-income and middle-income countries (LMICs) without universal access to clean fuels. Methods: We did a geospatial modelling study to map the prevalence of solid-fuel use for cooking at a 5 km × 5 km resolution in 98 LMICs based on 2·1 million household observations of the primary cooking fuel used from 663 population-based household surveys over the years 2000 to 2018. We use observed temporal patterns to forecast household air pollution in 2030 and to assess the probability of attaining the Sustainable Development Goal (SDG) target indicator for clean cooking. We aligned our estimates of household air pollution to geospatial estimates of ambient air pollution to establish the risk transition occurring in LMICs. Finally, we quantified the effect of residual primary solid-fuel use for cooking on child health by doing a counterfactual risk assessment to estimate the proportion of deaths from lower respiratory tract infections in children younger than 5 years that could be associated with household air pollution. Findings: Although primary reliance on solid-fuel use for cooking has declined globally, it remains widespread. 593 million people live in districts where the prevalence of solid-fuel use for cooking exceeds 95%. 66% of people in LMICs live in districts that are not on track to meet the SDG target for universal access to clean energy by 2030. Household air pollution continues to be a major contributor to particulate exposure in LMICs, and rising ambient air pollution is undermining potential gains from reductions in the prevalence of solid-fuel use for cooking in many countries. We estimated that, in 2018, 205 000 (95% uncertainty interval 147 000–257 000) children younger than 5 years died from lower respiratory tract infections that could be attributed to household air pollution. Interpretation: Efforts to accelerate the adoption of clean cooking fuels need to be substantially increased and recalibrated to account for subnational inequalities, because there are substantial opportunities to improve air quality and avert child mortality associated with household air pollution. Funding: Bill &amp; Melinda Gates Foundation
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