73 research outputs found

    Histopathological alterations in testicular tissue of male rats exposed to arsenic

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    The present study was designed to investigate the adverse effect of arsenic on testicular tissue of Swiss albino male rats. Sodium arsenite was administered to adult male rats by gavage at the doses 1, 2 and 3 mg/kg body weight for 30 days. After the treatment, the testis were processed for histopathological observations. Sodium arsenite caused remarkable reduction in testicular weight (P<0.05), while the body weight of experimental animals were reduced but not significantly (P<0.05). Histological evaluation revealed dose-dependent, gradual destruction in histoarchitecture of testicular tissue. Sodium arsenite exposure caused complete arrest of spermatogenesis with disfigured seminiferous tubules in the testes .The lumens of the tubules were devoid of spermatids and were in places filled with cellular debris. The germinal epithelium was distorted. At places interstitial odema was also evident. Sertoli and Leydig cells were damaged. Along with structural alterations, fertility rate in experimental animals was significantly decreased at higher doses i.e. 2 and 3 mg/kg, as 100% infertility was observed. After withdrawal of the treatment over a period of 30 days, recovery was observed in low dose groups as few female rats became pregnant. The study concluded that exposure of arsenic causes testicular toxicity in male albino rat

    Effects of SiO(2) and TiO(2) fillers on thermal and dielectric properties of eco-friendly bismuth glass microcomposites of plasma display panels

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    The effects of SiO(2) (amorphous) and TiO(2) (crystalline, rutile) fillers on softening point (T (s)), glass transition temperature (T (g)), coefficient of thermal expansion (CTE), and dielectric constant (E >) of zinc bismuth borate, ZnO-Bi(2)O(3)-B(2)O(3) (ZBIB) glass microcomposites have been investigated with a view to its use as the white back (rear glass dielectric layer) of plasma display panels (PDPs). The experimentally measured properties have also been compared with those of theoretically predicted values. Both the experimental and theoretical trends of these properties with added filler contents correlate very well. The interaction of fillers with glass which occurred during sintering at 560A degrees C has also been monitored by XRD and FTIR spectroscopic analyses. The microstructures and distribution of fillers in the glass matrix have been analyzed by SEM images. It is observed that the fillers have partially dissolved in the glass at the firing temperature leaving some unreacted filler as residue which results in ceramic-glass microcomposites. In consideration of the desired properties of white back of PDPs, the addition of TiO(2) filler to ZBIB glass is found to be more preferable than SiO(2) filler. The addition of 10 wt% TiO(2) filler yielded T (s), T (g), CTE and E > values of 560A degrees C, 480A degrees C, 82 x 10(-7)/K and 14 center dot 6 which are found to meet the desired values of < 580A degrees C, < 500A degrees C, < 83 x 10(-7)/K and < 15, respectively with respect to use of PD200 glass as substrate in PDP technology

    Influence of SiO(2) and Al(2)O(3) Fillers on Thermal and Dielectric Properties of Barium Zinc Borate Glass Microcomposites for Barrier Rib of Plasma Display Panels (PDPs)

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    In a lead-free low temperature sinterable multicomponent barium zinc borate glass system, BaO-ZnO-B(2)O(3)- SiO(2)-Li(2)O-Na(2)O (BZBSLN), the influence of SiO(2) (amorphous) and Al(2)O(3) (crystalline, a-alumina) ceramic fillers on the softening point (T(s)), glass transition temperature (T(g)), coefficient of thermal expansion (CTE), and dielectric constant (epsilon(r)) has been investigated with a view to its use as the barrier ribs of plasma display panels (PDPs). The interaction of fillers with glass which occurred during sintering at 570 degrees C has also been studied by XRD and FTIR spectroscopic analyses. It is observed that the filler has partially dissolved in the glass at the sintering temperature leaving some residual filler which results in ceramic-glass microcomposites. The distribution of fillers in the glass matrix and microstructures of the composites have been analyzed by SEM images. It has been seen that the T(s), T(g), CTE and epsilon(r) slightly increased with the increase of Al(2)O(3) content. In the case of SiO(2) filler, the T(s) and T(g) gradually, increased whereas CTE and epsilon(r) gradually decreased along with the addition or SiO(2). These experimentally measured properties have also been compared with the theoretically predicted values. Both the experimental and theoretical predictions of these properties with added filler contents have been found to be correlated very well. In consideration of the desired properties of barrier rib of PDPs with respect to use on PD200 glass substrates, the addition of Al(2)O(3) filler to BZBSLN glass has been found to be more preferable than SiO(2) filler

    Influence of combined Al(2)O(3)-SiO(2) filler on thermal and dielectric properties of barium zinc borate glass microcomposites for barrier ribs of plasma display panels

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    The co-effects of Al(2)O(3)-SiO(2) filler to an extent of 25 wt.% on thermal (softening point and coefficient of thermal expansion) and dielectric constant of lead free BaO-ZnO-B(2)O(3)-SiO(2)-Li(2)O-Na(2)O (BZBSLN) glasses have been explored with a view to use as barrier ribs of plasma display panels (PDPs). The interaction of fillers with glass occurred during firing (570 degrees C) has also been investigated by XRD, SEM micrograph and FTIR spectroscopy analyses. The fillers have been found to be partially dissolved in the glass at the firing temperature leaving some unreacted residual filler which result in ceramic-glass microcomposites. All the properties are found to follow the same experimental and theoretical trends, and regulate by the covalent character as well as the optical basicity of microcomposites. Addition of combined filler found to be yielded the required properties and meeting the criteria for barrier rib application

    VALIDATION OF GOMOS OZONE PROFILES USING NDSC LIDAR : STATISTICAL COMPARISONS

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    ABSTRACT The lidars deployed in the NDSC framework have been used for the validation of GOMOS onboard ENVISAT. During the commissioning phase around ten coincidences per site have been investigated. No significant bias, larger than ±5 %, has been reported except around 50 km and 20 km where both techniques are known to present some limitations. The estimated errors of both GOMOS and lidar are in good agreement with the standard deviation of the differences between coincidences. At higher latitude, comparisons are not so good because of the measurement conditions of bright limb during this period

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
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