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Tannase is an enzyme used in various industries and produced by a large number of microorganisms. The aim of this study was to evaluate tannase production to determine the biochemical, kinetic, and thermodynamic properties and to simulate tannase in vitro digestion. The tannase-producing fungal strain was isolated from “jamun” leaves and identified as Aspergillus tamarii. Temperature at 26°C for 67?h was the best combination for maximum tannase activity (6.35-fold; initial activity in Plackett–Burman design—15.53?U/mL and average final activity in Doehlert design—98.68?U/mL). The crude extract of tannase was optimally active at 40°C, pH 5.5 and 6.5. Moreover, tannase was stimulated by Na+, Ca2+, Mg2+, and Mn2+. The half-life at 40°C lasted 247.55?min. The free energy of Gibbs, enthalpy, and entropy, at 40°C, was 81.47, 16.85, and ?0.21?kJ/mol?·?K, respectively. After total digestion, 123.95% of the original activity was retained. Results suggested that tannase from A. tamarii URM 7115 is an enzyme of interest for industrial applications, such as gallic acid production, additive for feed industry, and for beverage manufacturing, due to its catalytic and thermodynamic properties.  相似文献   
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ABSTRACT

Social networking technology has the potential to transform how organizations communicate, cooperate, and connect with key stakeholders. Our research explores how social networking technologies are deployed within organizations and how the use of these technologies is related to effectiveness in organizational communication and promotion. We also identify the facilitating factors and constraints around the use of social networking tools for communication. To examine these questions, we conducted interviews with 131 senior level executives across a broad range of organizations and employed both quantitative and qualitative methods of analysis. The executives were asked to rate numerically and then discuss in narrative form a series of questions about IT strategy and issues affecting social networking in their organization. We find important differences both in the types of tools used as well as how they are used and discuss the implications of our findings for companies seeking to more effectively harness social networking technologies.  相似文献   
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The anti-inflammatory effects of Acanthopanax senticosus leaves (ASL) and the effects of extrusion were evaluated. ASL exhibited in vitro and in vivo antiinflammatory activities in experimental systems. Extrusion increased the effect of ASL. ASL reduced C48/80-induced histamine release from HMC-1 cells as well as in vivo model, suggesting that ASL induces mast cell stabilization and has an anti-histamine activity. The effects of ASL and extruded ASL (ASLE) on pro-inflammatory cytokine production were evaluated. ASL treatment reduced MCP- 1, TNF-α, and IL-1β mRNA expressions and decreased their protein levels in HMC-1 cells. Decreases in serum NO, MDA, and TNF-α levels were observed in acute inflammatory rats, and extrusion increased the effects of ASL in a dose-dependent manner. These data support pharmacological basis of ASL and the effect of extrusion for future treatment of inflammation.  相似文献   
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Most developing countries include rural electrification programs in their efforts to improve social conditions. There are, however, several obstacles to the evaluation of such programs and therefore of their social, economic, environmental and energy impacts on the target population, particularly on impoverished communities located in remote areas. Evaluation of the efficacy of public policies aimed at rural electrification in South Africa, China, India and Brazil enables such actions to be quantified and re-considered so as to bolster the sustainability of their planning and implementation and also so as to enable comprehension of the significance of access to electricity in relation to other aspects of the drive to improve living standards. The provision of electric energy amounts to more than access to a public service and should be considered an essential right, in a context of social equity and justice, which permits social integration and the access to other equally essential services.  相似文献   
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This work investigated the pH, titratable acidity and total solids of the cassava starch fermentation water, using the traditional method and a method modified through the addition of glucose. Sour cassava starch production controlled by the characteristic of the fermentation water produced the best product (biscuit specific volume of 7.66 ± 0.41 mL g?1) at 33th day of fermentation in the modified method and at 85th day (biscuit specific volume of 6.53 ± 0.59 mL g?1) in traditional method. But, comparatively to the commercial sour cassava starch (biscuit specific volume of 3.48 ± 0.12 mL g?1), both traditional and modified methods, controlled by titratable acidity of fermentation water, can be retired from the fermentation tank in the 19th and 32th day of fermentation, with biscuit specific volume of 4.75 ± 0.30 and 5.17 ± 0.46 mL g?1, respectively. Determining fermentation time can help to standardise sour cassava starch and to promote future applications of the fermentation water as a raw material.  相似文献   
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Determination of optimum hazelnut roasting conditions   总被引:1,自引:0,他引:1  
The objective of this study was to test the hypothesis that the roasting conditions used for hazelnuts, such as the air temperature, air velocity and roasting time (independent variables), could be optimized by using Response Surface Methodology. Effects of independent variables on sensory and physical characteristics were determined. A consumer test was used to determine the acceptable samples. Very dark and very light roasted samples, corresponding to 165 °C, 3 m/s, 25 min and 125 °C, 1 m/s, 15 min process conditions, respectively, were unacceptable. Superimposed contour plots were used to determine the values of independent variables and these showed the process conditions where all product characteristics were acceptable to consumers. At low velocity (0.3 m/s), acceptable products were produced at about 165–179 °C for 20–25 min. When air velocity increased, air temperature shifted to lower temperatures. Samples roasted at 145 °C, 2 m/s, 28 min, 165 °C, 1 m/s, 25 min and 145 °C, 3.7 m/s, 20 min produced the most acceptable products. The sample roasted at 165 °C, 1 m/s, 25 min required the least air velocity and was the most economical in terms of energy consumed among the samples rated most acceptable by consumers.  相似文献   
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Summary Poly(4,4-diphenylether-1,3,4-oxadiazole)s have been prepared by polycondensation of 4,4-diphenylether dicarboxylic acid and hydrazine sulphate, HS, in poly(phosphoric acid), PPA, under different reaction condictions. The products were characterized by viscometry, gel permeation chromatography, 1H-NMR spectrometry and thermogravimetric analysis. Dense membranes have been prepared and submitted to gas transport and wide angle X-ray diffraction, WAXD, experiments. The differences found in permeability and selectivity parameters, as well as in density and WAXD results, are discussed in terms of their solution viscosities and hydrazide repeat unit contents.  相似文献   
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Over the last decade, array detection has been developed to qualitatively assess the presence of genetically modified organisms (GMOs). To date, DNA array systems have the highest capabilities as a result of GMOs analysis. We describe the construction of an array platform in the sandwich hybridization format for the detection of transgenic promoter of Cauliflower mosaic virus (CaMV; p35S). Sequence-specific signal development has been achieved by a sandwich complex composed of a surface immobilized capture probe and a fluorescein-tagged signal probe, which are partially complementary to the p35S oligonucleotide. We used poly-l-lysine-coated glass slides as support material, on which capture probes were immobilized by a heterobifunctional cross-linker. The comparative results of optimization studies including cross-linker types probe concentrations and hybridization conditions (sequence, temperature and duration) were reported. An optimum hybridization signal was obtained with a 32.5 ? cross-linker, 10???M capture and 20???M signal probe concentrations, respectively. A relatively short hybridization time (2.5?h) provided reproducible array signals. No significant effect of hybridization sequence on the fluorescence intensity was observed. The described platform can specifically detect label-free transgenic sequences with a target of 0.01???M concentration, while the optimized system exhibits great potential for the application of different GMO target sequences (p35S, tNOS, bar and cry) to multiplex array formats.  相似文献   
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