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Paddy and Water Environment - Alternate wetting and drying (AWD) irrigation practice in paddy cultivation requires a safe soil moisture stress level in the root zone for which irrigation water...  相似文献   
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Polyvinylpyrrolidone/date palm leaf fiber (PVP/DPL) biocomposites were prepared by melt mixing fabrication technique with different weight percentage of fibers. DPL fibers were chemically modified by acrylic acid in order to have better dispersion and compatibility with PVP matrix. The interaction of DPL fibers with PVP matrix was studied by Fourier transforms infrared spectroscopy (FTIR). Field emission scanning electron microscope (FESEM) was used for the study the morphology of chemically modified DPL fibers and PVP/DPL biocomposites. Mechanical properties were improved with fiber loading due to strong interfacial adhesion between PVP and DPL fibers. The storage modulus, loss modulus and tan delta values of PVA/DPL biocomposites were measured by DMTA. The rheological properties were investigated to study the shearing storage and loss modulii along with complex viscosity of biocomposites. The thermal and conducting properties of biocomposites were measured and compared with that of virgin PVP.  相似文献   
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Curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3, 5-dione], the main constituent of the rhizomes of the plant Curcume longa L. (turmeric), is a powerful antioxidant in both enzymatic and nonenzymatic systems. The interactions of curcumin with egg and soy phosphatidylcholine were followed by fluorescence spectroscopy. Curcumin had very weak fluorescence in aqueous system, which was enhanced in apolar environments. Curcumin emitted at 490 nm after being excited at 451 nm in phosphatidylcholine micelles. The equilibrium constants for the interaction of curcumin with egg and soy phosphatidylcholine were (3.26 +/- 0.2) x 10(5) and (2.64 +/- 0.2) x 10(5) M(-1), respectively. From the Scatchard plot of the fluorometric data, it was inferred that one molecule of curcumin could bind six molecules of phosphatidylcholine. The equilibrium constant for the phosphatidylcholine-curcumin interaction decreased with temperature, indicating the amphiphilic nature of curcumin. The DeltaG, DeltaH, and DeltaS values obtained for the interaction of egg phosphatidylcholine-curcumin were -7.8 +/- 0.3 kcal/mol, -9.6 +/- 0.4 kcal/mol, and -6.8 +/- 0.2 cal/mol/K, respectively. The fluorescence anisotropy measurements of curcumin with phosphatidylcholine suggested that the anisotropy of the curcumin molecule did not change in phosphatidylcholine. The interaction of divalent metal ions with phosphatidylcholine-curcumin in comparison with phosphatidylcholine-1-anilino-8-naphathalenesulfonic acid complex suggested the strong binding of curcumin to metal ions.  相似文献   
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The mesenteric lymph nodes (MLN) of buffaloes (n = 100) were examined for the presence of parasitic infection. The nymphal stage of Linguatula serrata was observed in two buffaloes. A single white-coloured nymph with transversely striated spines on a segmented body, two pairs of oral suckers and hooks was observed in the MLN. The morphometrics of the nymphs were studied. The affected lymph nodes were grossly enlarged with cyst and showed pathological lesions of fibroblastic reaction with a mild underlying inflammatory zone.  相似文献   
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Current widespread and intensive soil degradation in India has been driven by unprecedented levels of population growth, large-scale industrialization, high-yield agriculture, urban sprawl and the spread of human infrastructure. The damage caused to managed and natural systems by soil degradation threatens livelihoods and local services and leads to national socio-economic disruption. Human-induced soil degradation results from land clearing and deforestation, inappropriate agricultural practices, improper management of industrial effluents and wastes, careless management of forests, surface mining, urban sprawl, and ill-planned commercial and industrial development. Of these, inappropriate agricultural practices, including excessive tillage and use of heavy machinery, over-grazing, excessive and unbalanced use of inorganic fertilizers, poor irrigation and water management techniques, pesticide overuse, inadequate crop residue and/or organic carbon inputs, and poor crop cycle planning, account for nearly 40% (121 Mha) of land degradation across India. Globally, human activities related to agriculture contribute to the transgression of four of the nine Planetary Boundaries proposed by Rockström et al. (2009): Climate Change, Biodiversity Integrity, Land-system Change, and altered Phosphorus and Nitrogen Biogeochemical Flows. This review focuses on how knowledge of soil processes in agriculture has developed in India over the past 10 years, and the potential of soil science to meet the objectives of the United Nations' Sustainable Development Goal 2: Zero Hunger (End hunger, achieve food security, improved nutrition and promote sustainable agriculture), using the context of the four most relevant Planetary Boundaries as a framework. Solutions to mitigate soil degradation and improve soil health in different regions using conservation agricultural approaches have been proposed. Thus, in this review we (1) summarize the outputs of recent innovative research in India that has explored the impacts of soil degradation on four Planetary Boundaries (Climate Change, Biodiversity Loss, Land-system Change, and altered Biogeochemical Flows of Phosphorus and Nitrogen) and vice-versa; and (2) identify the knowledge gaps that require urgent attention to inform developing soil science research agendas in India, to advise policy makers, and to support those whose livelihoods rely on the land.  相似文献   
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