205 research outputs found

    A Simple Photometer Based on a New Tri-Colour Light-Emitting Diode

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    Light-emitting diodes which can produce blue, green, and red light and therefore cover most of the visible range have recently been introduced. Such a device is used in the construction of a simple and compact photometer for molecular absorbance measurements in analytical chemistry

    EFFECTS OF INSTITUTIONAL FACTORS ON NON-PERFORMING LOANS IN STATE BANKS OF SRI LANKA

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    Non-Performing Loans (NPL) is a significant phenomenon especially in the State Banks of Sri Lanka. This is a typical feature in the majority of the banks in Asian countries. NPL arise based on several reasons. Among them, this study examines the significance of the institutional factors on Non-Performing loans. The population comprised of loan borrowers from State banks in Sri Lanka. Sample comprised 102 loan borrowers selected through random sampling from selected state banks in Western Province that borrowed loans during 2013-2018.. Data was collected through a questionnaire based on 08 variables identified through literature review and analyzed using independent sample t tests. Results show except management efficiency all other variables influenced on NPL. Policies should formulate to mitigate the effects of influential variables.&nbsp

    Comparative study of thermal efficiency in five different fuel wood cook stoves for conserving biomass energy sources in Sri Lanka

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    Minimum energy requirements for cooking and heating may be estimated as 6 - 10 GJ, or 0.5 - 1 m³ of fuel wood per person per year. Inefficient use of biomass for anthropogenic activities causes reduction of biomass availability. Therefore, there is a scientific need to identify most efficient cook stoves to improve the efficiency of using bio mass for cooking for the sake of saving forest cover and for the solution of the green energy requirement.The present research study formulated to evaluate the efficiency of existing cook stoves such as “Batapola Lipa” (BS), “Anagi Lipa” (AS), and traditional three stone cook stove (TS) with newly developed cook stoves such as traditional three stone cook stove with grater (TSG) and a prototype metal stove (PMS) developed by the Department of Agricultural Engineering, Faculty of Agriculture, University of Ruhuna. The standard boiling water laboratory test was done for studying the thermal efficiency. Cinnamon sticks were used as the source of biomass. Initial and boiling water temperatures, amount of water boiled and evaporated, amount of biomass utilized and unburned remaining biomass in weight basis after the boiling test, were measured and percent heat utilized and power output of stoves were calculated.The results which were analyzed using ANOVA procedure with Duncan’s Multiple Range Test, revealed that energy output of the BS, AS, TS, TSG and PMS, were observed as 15.1 kW, 5.8 kW, 3.9 kW, 4.7 kW and 14.3 kW respectively. Comparatively higher percent heat utilized value were observed in TSG, AS and BS than TS and PMS. The BS, TS, TSG, PMS consumed 190, 274, 172, 298 g, within 3.95, 22, 11.25, 6.52 minutes respectively. Lowest biomass consumption rate was observed in TSG. It revealed that 102 g of biomass and 10.75 minutes can be saved by TSG than TS for boiling one liter of water. Therefore the significant amount of fuel wood can be saved successfully by introducing a grater to the traditional three stone cook stove which may save natural forests resources in Sri Lanka

    Muscle p70S6K phosphorylation in response to soy and dairy rich meals in middle aged men with metabolic syndrome: a randomised crossover trial

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    The mammalian target of rapamycin (mTOR) pathway is the primary regulator of muscle protein synthesis. Metabolic syndrome (MetS) is characterized by central obesity and insulin resistance; little is known about how MetS affects the sensitivity of the mTOR pathway to feeding

    Cancer prevention and therapy through the modulation of the tumor microenvironment

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    Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer

    小学校教科書語彙の研究

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    <div><p>Abstract</p><p><i>Leishmania</i> parasites replicate within the phagolysosome compartment of mammalian macrophages. Although <i>Leishmania</i> depend on sugars as a major carbon source during infections, the nutrient composition of the phagolysosome remains poorly described. To determine the origin of the sugar carbon source in macrophage phagolysosomes, we have generated a N-acetylglucosamine acetyltransferase (GNAT) deficient <i>Leishmania major</i> mutant (<i>∆gnat</i>) that is auxotrophic for the amino sugar, N-acetylglucosamine (GlcNAc). This mutant was unable to grow or survive in <i>ex vivo</i> infected macrophages even when macrophages were cultivated in presence of exogenous GlcNAc. In contrast, the <i>L</i>. <i>major ∆gnat</i> mutant induced normal skin lesions in mice, suggesting that these parasites have access to GlcNAc in tissue macrophages. Intracellular growth of the mutant in <i>ex vivo</i> infected macrophages was restored by supplementation of the macrophage medium with hyaluronan, a GlcNAc-rich extracellular matrix glycosaminoglycan. Hyaluronan is present and constitutively turned-over in <i>Leishmania</i>-induced skin lesions and is efficiently internalized into <i>Leishmania</i> containing phagolysosomes. These findings suggest that the constitutive internalization and degradation of host glycosaminoglycans by macrophages provides <i>Leishmania</i> with essential carbon sources, creating a uniquely favorable niche for these parasites.</p></div

    Mineralogical evolution of cement pastes at early ages based on thermogravimetric analysis (TGA)

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    [EN] Ordinary thermogravimetric analysis (TG) and high-resolution TG tests were carried out on three different Portland cement pastes to study the phases present during the first day of hydration. Tests were run at 1, 6, 12 and 24 h of hydration, in order to determine the phases at these ages. High-resolution TG tests were used to separate decompositions presented in the 100¿200 C interval. The non-evaporable water determined by TG was used to determine hydration degree for the different ages. The effect of particle size distribution (PSD) on mineralogical evolution was established, as well as the addition of calcite as mineralogical filler. Finer PSD and calcite addition accelerate the hydration process, increasing the hydration degree on the first day of eaction between water and cement. According to high-resolution TG results, it was demonstrated that ettringite was the only decomposed phase in the 100¿200 C interval during the first 6 h of hydration for all studied cements. 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