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751.
The present study has carried out safety evaluations on an ethanolic extract of red cabbage (RC) leaves in terms of acute and subchronic oral toxicity tests as per Organisation for Economic Cooperation and Development (OECD) guidelines in Swiss albino mice. Single-dose administration of RC extract (1000, 2000, 3000, 4000, or 5000 mg/kg body weight) to Swiss albino mice did not manifest toxicity or any significant adverse behavioral alterations. Chronic administration of RC extract (1000, 2000, and 3000 mg/kg body weight) for 28 d also did not register any significant alterations in fluid intake, organ weights, plasma lipid profile, plasma creatine kinase-MB, lactate dehydrogenase, aspartate transaminase, alanine transaminase, creatinine, electrolytes, and calcium levels, and the total blood count showed a nonsignificant change. However, significant reduction in body-weight gain, food intake, red blood cell count, and hemoglobin content along with higher alkaline phosphatase, bilirubin, and urea levels was observed in mice treated with 3000 mg/kg body weight for 28 d. Since there was no mortality up to a dose of 5000 mg/kg body weight, 50% lethal dose (LD(50)) could not be determined, and hence, it can be assumed that, LD(50) of RC extract is >5000 mg/kg. No observable adverse effect level dose of the RC extract was found to be 2000 mg/kg body weight. Hence, consumption of RC extract for various medicinal purposes is safe. Practical Application: RC is a popularly consumed foodstuff that has been ubiquitously reported to exert medicinal properties. It is mandatory to understand the highest permissible consumption limit of any food supplement to avoid toxicity. This study establishes the safe dose of RC. These results can be of relevance for the scientific fraternity as well as laymen who consume this vegetable or its phytochemical preparation.  相似文献   
752.
Hydrogen (H2) production and end-product synthesis were characterized in a novel, mesophilic, cellulolytic, anaerobic bacterium, Clostridium termitidis strain CT1112, isolated from the gut of the termite, Nasutitermes lujae. Growth curves, pH patterns, protein content, organic acid synthesis, and H2 production were determined. When grown on 2 g l−1 cellobiose and 2 g l−1 α-cellulose, C. termitidis displayed a cell generation time of 6.5 h and 18.9 h, respectively. The major end-products synthesized on cellobiose included acetate, hydrogen, CO2, lactate, formate and ethanol, where as on cellulose, the major end-products included hydrogen, acetate, CO2 and ethanol. The concentrations of acetate were greater than ethanol, formate and lactate on both cellobiose and α-cellulose throughout the entire growth phase. Maximum yields of acetate, ethanol, hydrogen and formate on cellobiose were 5.9, 3.7, 4.6 and 4.2 mmol l−1 culture, respectively, where as on cellulose, the yields were 7.2, 3.1, 7.7 and 2.9 mmol l−1 culture, respectively. Hydrogen and ethanol production rates were slightly higher in C. termitidis cultured on cellobiose when compared to α-cellulose. Although, the generation time on α-cellulose was longer than on cellobiose, H2 production was favored corresponding to acetate synthesis, thereby restricting the carbon flowing to ethanol. During log phase, H2, CO2 and ethanol were produced at specific rates of 4.28, 5.32, and 2.99 mmol h−1 g dry weight−1 of cells on cellobiose and 2.79, 2.59, and 1.1 mmol h−1 g dry weight−1 of cells on α-cellulose, respectively.  相似文献   
753.
Heat transfer in a two-layered fluid system is of great importance in a variety of applications. Control and optimization of convective heat transfer of the immiscible fluids needs complete understanding of all phenomena, especially those induced by surface tension at the fluid interface. The present work is focused on rather complex convective flow and heat transfer phenomena in a cavity, which can be subject to both buoyancy and thermocapillary effects in addition to the influence of magnetic field applied for flow control. With the encapsulant liquid posing magnetic properties, a magnetic force can arise to either enhance or counterbalance the gravity effect when the cavity is placed in a non-uniform magnetic field. In our study, the velocity and temperature distribution of the system can be significantly altered to change the heat transfer by varying intensity and gradient of the applied magnetic field. Preliminary results of numerical computation presented here are for a two-layered liquid cavity MnCl2·4H2O and Fluorinert FC40 under various magnetic fields intensities.  相似文献   
754.
In this study, wastewater obtained from a sewage treatment plant was treated successively by using microbial consortium and macroalgae Kappaphycus alvarezii to generate microbial sludge and algal biomass. The production of green fuel was carried out via co-gasification of microbial sludge and macroalgae Kappaphycus alvarezii for a duration of 60 min, feedstock to solvent ratio (5 to 20 g of feedstock in 200 mL), sludge to algae ratio (ranging from 1:1 to 3:1) and temperature (300–400 °C) respectively. Maximum bio-hydrogen yield was 36.1% and methane yield was 38.4% at a temperature of 360 °C at a feedstock to solvent ratio of 15:200 g/mL and sludge to algae ratio of 2:1 individually. The liquid by product of co-gasification process was later subjected to photocatalytic reforming, resulted in an enhanced hydrogen composition of 61.25%.  相似文献   
755.
The production of methane by steam-reforming of naphtha involves both rate controlling formation of carbon monoxide and hydrogen, followed by near equilibrium reactions of carbon monoxide with steam and hydrogen. In this paper a model is proposed for predicting the composition of the product gas for a single, isothermal/catalyst particle. For this system of both equilibrium and rate controlling reactions a new type of boundary condition is needed for the outer surface of the catalyst particle.The results (calculated for typical operating conditions of 400–530°C, 15–20 atm pressure, and a feed molal ratio of steam to naphtha to 6–25)The results presented for a single particle can be used with intrareactor conservation equations to predict the behavior of an integral reactor, for ex  相似文献   
756.
757.
Flounders and cuttlefish have an impressive ability to change colouration, for camouflage and, in the case of cuttlefish, for communication. We pursue the hypothesis that these diverse patterns are created by combining a small number of distinct pattern modules. Independent component analysis (ICA) is a powerful tool for identifying independent sources of variation in linear mixtures of signals. Two versions of ICA are used, one assuming that sources have independence over time, and the other over space. These reveal the modularity of the skin colouration system, and suggest how the pattern modules are combined in specific behavioural contexts. ICA may therefore be a useful tool for studying animal camouflage and communication.  相似文献   
758.
Asian Indians have high insulin resistance, hyperinsulinemia, a high prevalence of diabetes, and a high waist to hip ratio (WHR), although the rate of obesity is low. WHR and visceral fat (VF) are highly correlated, and both are associated with insulin resistance. This study was performed to determine the normal ranges of abdominal fat distribution (subcutaneous [SF] and VF) in nondiabetic South Indians and also to study its correlations with WHR, plasma insulin, and metabolic profiles. Fat areas were measured by computed axial tomographic scan at the L4 to L5 level. Mean areas of SF and VF in men and women in this study were similar to the values in white populations. Women had significantly less VF than men. Gender differences were observed in the contribution of fat areas to anthropometric, hormonal, and metabolic variables. In general, in men, total fat (TF) area showed significant independent correlation with body mass index (BMI), WHR, and total cholesterol, and VF correlated with insulin secretion. In women, TF and BMI were correlated and SF showed a correlation with total cholesterol. Insulin secretion in women did not show a correlation with fat areas.  相似文献   
759.
760.
Tensile tests were conducted at 4.2°K on both longitudinal and transverse specimens machined from zirconium plate. In this plate the basal planes of the grains were strongly aligned parallel to and distributed nearly uniformly about the rolling direction. The metal had higher ductility at 4.2°K than at room temperature. Prestraining transverse specimens at 4.2°K produced higher room temperature damping capacity than prestraining at 77°K. All stress-strain curves for the 4.2°K tests exhibited characteristic sudden drops in the load. Transverse specimens showed a much higher incidence of twinning, greater strain hardening, more plastic deformation between serrations, and fewer serrations than longitudinal specimens. The experimental evidence is in agreement with Kula and DeSisto’s conclusions that twinning per se is probably not responsible for the discontinuous yielding. The present observations are also consistent with Basinski’s hypothesis that the load drops are related to thermal softening. A simple calculation shows that at temperatures near absolute zero, the heat generated in a specimen during deformation is much more than that necessary to cause an instability and consequent load drop. Hence it is concluded that all the heat generated is not retained in the specimen and a large fraction must be lost to the surroundings. An estimate of the magnitude of the temperature rise associated with a typical load drop was made.  相似文献   
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