23 research outputs found

    Operational Characteristics of a Pressurised Van De Graaf Generator

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    NaCl pretreatment alleviates salt stress by enhancement of antioxidant defense system and osmolyte accumulation in mungbean (<i style="">Vigna radiata</i> L. Wilczek)

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    593-600Enhancement of salt (NaCl) tolerance by pretreatment with sublethal dose (50 mM) of NaCl was investigated in V. radiata seedlings. NaCl stress caused drastic effects on roots compared to shoots. Accompanying reductions in length, number of root hairs and branches, roots became stout, brittle and brown in color. Salt stress caused gradual reduction in chlorophyll, carotenoid pigment contents and chlorophyll fluorescence intensity also. Superoxide dismutase and catechol peroxidase activities increased under stress in both roots and leaves. But catalase activity showed an increase in roots and decrease in leaves. In these seedlings, the oxidative stress has been observed under salinity stress and the level of proline, H2O2 and malondialdehyde content were increased. But pretreatment with sublethal dose of NaCl was able to overcome the adverse effects of stress imposed by NaCl to variable extents by increasing growth and photosynthetic pigments of the seedlings, modifying the activities of antioxidant enzymes, reducing malondialdehyde and H2O2 content and increasing accumulation of osmolytes like proline. Thus, mungbean plants can acclimate to lethal level of salinity by pretreatment with sublethal level of NaCl, improving their health and production under saline condition

    Identification of Long-Term Behavior of Natural Circulation Loops: A Thresholdless Approach from an Initial Response

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    Natural circulation loop (NCL) systems are buoyancy-driven heat exchangers that are used in various industrial applications. The concept of passive heat exchange in NCL systems is attractive, because there is no need for an externally driven equipment (e.g., a pump) to maintain the fluid circulation. However, relying on buoyancy as the sole driving force may lead to several potential difficulties, one of which is generation of (possibly) time-varying nonlinearities in the dynamical system, where a difference in the time scales of heat transfer and fluid flow causes the flow to change from a steady-state regime to either an oscillatory regime or a flow-reversal regime, both of which are undesirable. In this paper, an algorithm is developed using tools of symbolic time-series analysis (e.g., probabilistic finite state automata (PFSA)) for the purpose of identifying selected regimes of operation in NCL systems using only data from the early transient operation, where the underlying principle is built upon the concept of pattern classification from measurements of fluid-flow dynamics. The proposed method is shown to be capable of identifying the current regime of operation from the initial time response under a given set of operational parameters. The efficacy of regime classification is demonstrated by testing on two datasets, generated from numerical simulation of a MATLAB SimuLink model that has previously been validated with experimental data. The results of the proposed PFSA-based classification are compared with those of a hidden Markov model (HMM) that serves as the baseline

    Identification of Long-Term Behavior of Natural Circulation Loops: A Thresholdless Approach from an Initial Response

    No full text
    Natural circulation loop (NCL) systems are buoyancy-driven heat exchangers that are used in various industrial applications. The concept of passive heat exchange in NCL systems is attractive, because there is no need for an externally driven equipment (e.g., a pump) to maintain the fluid circulation. However, relying on buoyancy as the sole driving force may lead to several potential difficulties, one of which is generation of (possibly) time-varying nonlinearities in the dynamical system, where a difference in the time scales of heat transfer and fluid flow causes the flow to change from a steady-state regime to either an oscillatory regime or a flow-reversal regime, both of which are undesirable. In this paper, an algorithm is developed using tools of symbolic time-series analysis (e.g., probabilistic finite state automata (PFSA)) for the purpose of identifying selected regimes of operation in NCL systems using only data from the early transient operation, where the underlying principle is built upon the concept of pattern classification from measurements of fluid-flow dynamics. The proposed method is shown to be capable of identifying the current regime of operation from the initial time response under a given set of operational parameters. The efficacy of regime classification is demonstrated by testing on two datasets, generated from numerical simulation of a MATLAB SimuLink model that has previously been validated with experimental data. The results of the proposed PFSA-based classification are compared with those of a hidden Markov model (HMM) that serves as the baseline

    Treatment of thyroid associated ophthalmopathy : Comparison between radiotherapy with concurrent steroids and three floor orbital decompression

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    Abstract Thyroid associated orbitopathy is a common manifestation of Graves’ disease. There are many options which can be considered for treatment of this condition. In this case series, we reviewed the medical records of 16 patients suffering from thyroid ophthalmoplegia. 8 of them received radiotherapy and concurrent steroids and other 8 of them underwent 3 floor orbital decompression. They had a median follow up of around 2 years (from 2009 to 2011). After a median follow-up of 2 years, a subjective improvement in exophthalmos and vision was reported by nearly all patients at the end of RT but only 4 patients reported a decrease in their diplopia immediately after therapy. Symptoms continued to improve with time in many patients: 25% had complete reversal of their symptoms and signs, and the remaining 75% had partial improvement. But none of the patients who underwent surgery had improvement in diplopia, 3 of them had new onset diplopia. Only proptosis was corrected among them. We conclude that RT is an effective treatment option in Graves Ophthalmopathy. Based on our own clinical experiences and the literature data, the combination of RT and intravenous corticosteroid administration may improve the response rate

    Study on Morphological, Physiological Characteristics and Yields of Twenty-One Potato (<i>Solanum tuberosum</i> L.) Cultivars Grown in Eastern Sub-Himalayan Plains of India

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    The present study was conducted in the eastern sub-Himalayan plains of West Bengal, India, to evaluate 21 potato cultivars (including table- and processing-type) and assess their suitability in terms of improved physiological responses, yield performances, stability and profitability. A significant difference in various growth attributes, i.e., plant height, number of stems per plant, leaf area index (LAI), dry matter (DM) accumulation, and crop growth rate (CGR), was noted amongst different cultivars. Significant variation was also observed in net photosynthesis rate (NPR), transpiration rate (TR), and stomatal conductance rate (SCR) recorded at various stages of growth. Amongst all the cultivars, ‘Kufri Chipsona-4’ showed the highest SCR at both 60 and 80 days after planting (DAP), while ‘Kufri Pokhraj’ had the highest NPR at both 60 and 80 DAP. However, the highest TR was achieved with ‘Kufri Chipsona-3’and ‘Kufri Surya’ at 60 and 80 DAP, respectively. ‘Kufri Pukhraj’ and ‘Kufri Himsona’ achieved the maximum and minimum tuber bulking rate (TBR) values at initial growth stages (upto 60 days), respectively; however, ‘Kufri Arun’ and ‘Kufri Surya’ had significantly higher TBRs during the later part of growth (after 60 days to maturity), leading to higher tuber yields amongst the medium maturing cultivars. Among the 21 cultivars, ‘Kufri Arun’ showed the maximum total tuber yield (35.52 t/ha), followed by ‘Kufri Pukhraj’ (33.54 t/ha) with higher marketable grade tubers. In terms of production economics, ‘Kufri Arun’ achieved the maximum net return (USD 2137.4) and B:C (benefit:cost) ratio (2.17), suggesting the suitability of this cultivar in the eastern sub-Himalayan plains of West Bengal. The early maturing ‘Kufri Pukhraj’ and processing variety ‘Kufri Chipsona-3’ also showed their suitability in terms of net returns and B:C ratio. The heat-tolerant variety ‘Kufri Surya’ also achieved a tuber yield of 31 tha−1 with satisfying net return (USD 1596.9) and B:C ratio (1.88), suggesting the suitability of this cultivar in this region under terminal heat stress. However, the stability analysis showed that the cultivars ‘Kufri Khyati’ and ‘HPS II/67’ were the most stable in terms of additive main effect and multiplicative interaction (AMMI) stability value (ASV) and yield stability index (YSI), respectively
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