398 research outputs found
Numerical Solution of Coupled System of Nonlinear Partial Differential Equations Using Laplace-Adomian Decomposition Method
Aim of the paper is to investigate applications of Laplace Adomian Decomposition Method (LADM) on nonlinear physical problems. Some coupled system of non-linear partial differential equations (NLPDEs) are considered and solved numerically using LADM. The results obtained by LADM are compared with those obtained by standard and modified Adomian Decomposition Methods. The behavior of the numerical solution is shown through graphs. It is observed that LADM is an effective method with high accuracy with less number of components
Inhibition of lung serine proteases in mice: a potentially new approach to control influenza infection
<p>Abstract</p> <p>Background</p> <p>Host serine proteases are essential for the influenza virus life cycle because the viral haemagglutinin is synthesized as a precursor which requires proteolytic maturation. Therefore, we studied the activity and expression of serine proteases in lungs from mice infected with influenza and evaluated the effect of serine protease inhibitors on virus replication both in cell culture and in infected mice.</p> <p>Results</p> <p>Two different inbred mouse strains were investigated: DBA/2J as a highly susceptible and C57Bl/6J as a more resistant strain to influenza virus infection. The serine proteases from lung homogenates of mice exhibited pH optima of 10.00. Using the substrate Bz-Val-Gly-Arg-<it>p</it>-nitroanilide or in zymograms, the intensities of proteolysis increased in homogenates from both mouse strains with time post infection (p.i.) with the mouse-adapted influenza virus A/Puerto Rico/8/34 (H1N1; PR8). In zymograms at day 7 p.i., proteolytic bands were stronger and numerous in lung homogenates from DBA/2J than C57Bl/6J mice. Real-time PCR results confirmed differential expression of several lung proteases before and after infecting mice with the H1N1 virus. The most strongly up-regulated proteases were <it>Gzma</it>, <it>Tmprss4</it>, <it>Elane</it>, <it>Ctrl</it>, <it>Gzmc </it>and <it>Gzmb</it>. Pretreatment of mouse and human lung cell lines with the serine protease inhibitors AEBSF or <it>p</it>AB or a cocktail of both prior to infection with the H1N1 or the A/Seal/Massachusetts/1/80 (H7N7; SC35M) virus resulted in a decrease in virus replication. Pretreatment of C57Bl/6J mice with either AEBSF or a cocktail of AEBSF and <it>p</it>AB prior to infection with the H1N1 virus significantly reduced weight loss and led to a faster recovery of treated versus untreated mice while <it>p</it>AB alone exerted a very poor effect. After infection with the H7N7 virus, the most significant reduction of weight loss was obtained upon pretreatment with either the protease inhibitor cocktail or <it>p</it>AB. Furthermore, pretreatment of C57BL/6J mice with AEBSF prior to infection resulted in a significant reduction in the levels of both the H1N1 and H7N7 nucleoproteins in mice lungs and also a significant reduction in the levels of the HA transcript in the lungs of the H1N1- but not the H7N7-infected mice.</p> <p>Conclusion</p> <p>Multiple serine protease activities might be implicated in mediating influenza infection. Blocking influenza A virus infection in cultured lung epithelia and in mice by the used serine protease inhibitors may provide an alternative approach for treatment of influenza infection.</p
Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing
Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process
Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing
Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process
Relative Rate Observer Self-Tuning of Fuzzy PID Virtual Inertia Control for An Islanded microgrid
Expanding the usage of renewable energy in islanded microgrids leads to a reduction in its total inertia. Low inertia microgrids have difficulties in voltage and frequency control. That affected saving its stability and preventing a blackout. To improve low inertia islanded microgrids\u27 dynamic response and save their stability, this paper presented relative rate observer self-tuning fuzzy PID (RROSTF-PID) based on virtual inertia control (VIC) for an islanded microgrid with a high renewable energy sources (RESs) contribution. RROSTF-PID based on VIC\u27s success in showing remarkable improvement in the microgrid\u27s dynamic response and enhancement of its stability. Moreover, it handles different contingency conditions successfully by giving the desired frequency support. Ant colony optimization (ACO) technique is used to find the optimal values of the RROSTF-PID based on VIC parameters. Furthermore, using MATLAB TM/Simulink, RROSTF-PID based on VIC response is compared to Optimal Fuzzy PID (OF-PID) based VIC, Fuzzy PID (F-PID) based VIC, PID-based VIC, conventional VIC responses, and the microgrid without VIC response under different operation conditions
Study of sumac extract (Rhus coriaria L.), lactic acid and thyme oil as decontaminants for shelf life extension of refrigerated rabbit meat
In an attempt to improve the microbiological quality and extend the shelf-life of refrigerated rabbit meat, four groups of rabbit meat from New Zealand breed were prepared, the 1st group was untreated (control), while the other three groups were treated with lactic acid 0.5 %, thyme oil 0.5 % and water extract of sumac 8 % by dipping for 1, 1 and 10 min, respectively. Then the samples were refrigerated at 2 ± 1 °C to be periodically examined for their sensory and microbiological status. The control and treated samples showed excellent overall acceptability by panellists at zero-day of examination, off odours and tastes were noticed by the day 9, 12, 9 and 15 day of storage in control (C), lactic acid (LA), thyme oil (TO) and water extract of sumac (WES) treated groups, respectively. There was no significant differences in aerobic plate counts “APC” (at p < 0.05) between treated and untreated groups at zero and 3rd day of examination, while at 6th and 9th day of refrigerated storage, the values of APC were significantly lower in LA and WES treated groups than C and TO treated groups. The APC results confirm the concept that the slowest growth rate of the total bacterial population extends the shelf life of rabbit meat. Approximately, similar pattern to that of APC was observed in the results of coliforms (MPN). The MPN values of faecal coliforms and E. coli were relatively low, which could be attributed to the preparation of rabbit samples under strict hygienic measures. The obtained results in the present study suggest that WES can be used as a decontaminant for rabbit and poultry meat at each decontamination step instead of other chemical substances which could affect the acceptability of the final product and remain some hazardous residues. Keywords: sumac, rabbit, quality, shelf life, thyme oil, lactic acid
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