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51.
Hormones and neurotransmitters may mediate common responses through receptors that couple to the same class of heterotrimeric guanine nucleotide-binding (G) protein. For example, several receptors that couple to Gq class proteins can induce cardiomyocyte hypertrophy. Class-specific inhibition of Gq-mediated signaling was produced in the hearts of transgenic mice by targeted expression of a carboxyl-terminal peptide of the alpha subunit Galphaq. When pressure overload was surgically induced, the transgenic mice developed significantly less ventricular hypertrophy than control animals. The data demonstrate the role of myocardial Gq in the initiation of myocardial hypertrophy and indicate a possible strategy for preventing pathophysiological signaling by simultaneously blocking multiple receptors coupled to Gq.  相似文献   
52.
The use of biodiesel is rapidly expanding around the world, making it imperative to fully understand the impacts of biodiesel on the diesel engine combustion process and pollutant formation. Biodiesel is known as the mono-alkyl-esters of long chain fatty acids derived from renewable feedstocks, such as, vegetable oils or animal fats, for use in compression ignition engines. Different parameters for the optimization of biodiesel production were investigated in the first phase of this study, while in the next phase of the study performance test of a diesel engine with neat diesel fuel and biodiesel mixtures were carried out. Biodiesel was made by the well known transesterification process. Cottonseed oil (CSO) was selected for biodiesel production. Cottonseed is non-edible oil, thus food versus fuel conflict will not arise if this is used for biodiesel production. The transesterification results showed that with the variation of catalyst, methanol or ethanol, variation of biodiesel production was realized. However, the optimum conditions for biodiesel production are suggested in this paper. A maximum of 77% biodiesel was produced with 20% methanol in presence of 0.5% sodium hydroxide. The engine experimental results showed that exhaust emissions including carbon monoxide (CO) particulate matter (PM) and smoke emissions were reduced for all biodiesel mixtures. However, a slight increase in oxides of nitrogen (NOx) emission was experienced for biodiesel mixtures.  相似文献   
53.
Short-chain fatty acid (SCFA) acetate, a byproduct of dietary fiber metabolism by gut bacteria, has multiple immunomodulatory functions. The anti-inflammatory role of acetate is well documented; however, its effect on monocyte chemoattractant protein-1 (MCP-1) production is unknown. Similarly, the comparative effect of SCFA on MCP-1 expression in monocytes and macrophages remains unclear. We investigated whether acetate modulates TNFα-mediated MCP-1/CCL2 production in monocytes/macrophages and, if so, by which mechanism(s). Monocytic cells were exposed to acetate with/without TNFα for 24 h, and MCP-1 expression was measured. Monocytes treated with acetate in combination with TNFα resulted in significantly greater MCP-1 production compared to TNFα treatment alone, indicating a synergistic effect. On the contrary, treatment with acetate in combination with TNFα suppressed MCP-1 production in macrophages. The synergistic upregulation of MCP-1 was mediated through the activation of long-chain fatty acyl-CoA synthetase 1 (ACSL1). However, the inhibition of other bioactive lipid enzymes [carnitine palmitoyltransferase I (CPT I) or serine palmitoyltransferase (SPT)] did not affect this synergy. Moreover, MCP-1 expression was significantly reduced by the inhibition of p38 MAPK, ERK1/2, and NF-κB signaling. The inhibition of ACSL1 attenuated the acetate/TNFα-mediated phosphorylation of p38 MAPK, ERK1/2, and NF-κB. Increased NF-κB/AP-1 activity, resulting from acetate/TNFα co-stimulation, was decreased by ACSL1 inhibition. In conclusion, this study demonstrates the proinflammatory effects of acetate on TNF-α-mediated MCP-1 production via the ACSL1/MAPK/NF-κB axis in monocytic cells, while a paradoxical effect was observed in THP-1-derived macrophages.  相似文献   
54.
Boron doped TiO2 thin films have been successfully deposited on glass substrate and silicon wafer at 30°C from an aqueous solution of ammonium hexa-fluoro titanate and boron trifluoride by liquid phase deposition technique. The boric acid was used as an F scavenger. The resultant films were characterized by XRD, EDAX, UV and microstructures by SEM. The result shows the deposited film to be amorphous which becomes crystalline between 400 and 500°C. The EDAX and XRD data confirm the existence of boron atom in TiO2 matrix and a small peak corresponding to rutile phase was also found. Boron doped TiO2 thin films can be used as photocatalyst for the photodegradation of chlorobenzene which is a great environmental hazard. It was found that chlorobenzene undergoes degradation efficiently in presence of boron doped TiO2 thin films by exposing its aqueous solution to visible light. The photocatalytic activity increases with increase in the concentration of boron.  相似文献   
55.
Designing and synthesis of cost effective bulk metallic glasses (BMGs) has been of considerable interest during the last decade so that they can be made commercially viable. Among these, Zr-based BMGs have been reported extensively due to their attractive properties. An alloy having composition Zr65Cu18Ni9Al8 was designed and synthesized using 2-3 N pure materials by Cu mould casting. The alloy was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and high temperature differential scanning calorimetry (DSC). Thermal parameters like supercooled liquid region ΔTX, reduced glass transition temperature Trg, γand σ parameters were evaluated. Mechanical properties like microhardness, nanohardness, elastic modulus and fracture strength were measured. The alloy showed wide supercooled liquid region of 129±1 K with improved thermal stability. The alloy has considerable fracture strength along with fair amount of ductility.  相似文献   
56.
It is essential to develop and discover alternative eco-friendly antibacterial agents due to the emergence of multi-drug-resistant microorganisms. In this study, we isolated and characterized a novel bacterium named Terrabacter humi MAHUQ-38T, utilized for the eco-friendly synthesis of silver nanoparticles (AgNPs) and the synthesized AgNPs were used to control multi-drug-resistant microorganisms. The novel strain was Gram stain positive, strictly aerobic, milky white colored, rod shaped and non-motile. The optimal growth temperature, pH and NaCl concentration were 30 °C, 6.5 and 0%, respectively. Based on 16S rRNA gene sequence, strain MAHUQ-38T belongs to the genus Terrabacter and is most closely related to several Terrabacter type strains (98.2%–98.8%). Terrabacter humi MAHUQ-38T had a genome of 5,156,829 bp long (19 contigs) with 4555 protein-coding genes, 48 tRNA and 5 rRNA genes. The culture supernatant of strain MAHUQ-38T was used for the eco-friendly and facile synthesis of AgNPs. The transmission electron microscopy (TEM) image showed the spherical shape of AgNPs with a size of 6 to 24 nm, and the Fourier transform infrared (FTIR) analysis revealed the functional groups responsible for the synthesis of AgNPs. The synthesized AgNPs exhibited strong anti-bacterial activity against multi-drug-resistant pathogens, Escherichia coli and Pseudomonas aeruginosa. Minimal inhibitory/bactericidal concentrations against E. coli and P. aeruginosa were 6.25/50 and 12.5/50 μg/mL, respectively. The AgNPs altered the cell morphology and damaged the cell membrane of pathogens. This study encourages the use of Terrabacter humi for the ecofriendly synthesis of AgNPs to control multi-drug-resistant microorganisms.  相似文献   
57.
The reflected power function distribution (RPFD) has applications in the fields of reliability engineering and survival analysis. To identify and remove the variation in different reliability processes and also to monitor the reliability of machines where the number of errors follows RPFD, we develop control charts to keep the process in control. A memory less control chart like a Shewhart control chart, and two memory-based control charts like an exponentially weighted moving average (EWMA) control chart and a hybrid exponentially weighted moving average (HEWMA) control chart are discussed and compared with each other. Proposal of these control charts is based on two different estimators, the percentile estimator (PE) and the modified maximum likelihood estimator (MMLE). This study shows that an HEWMA control chart based on PE performs better than PE-based Shewhart and EWMA control charts, as well as MMLE-based Shewhart, EWMA, and HEWMA control charts.  相似文献   
58.
Early-age cracking can be a significant problem in concrete pavements, floors, and bridge decks. Various test methods have been developed to assess the potential for early-age cracking, however due to the economy and simplicity of the ring test, it has become widely used. Although the ring test procedures employed by various authors are similar, they vary in terms of curing duration, specimen geometry, and boundary conditions. This paper describes an experimental study of restrained ring specimens tested using different geometries and boundary conditions. Specimen geometry was found to have a significant effect on the stress development and age of cracking in the restrained ring specimens. Specimens that shrink uniformly along the radius show the greatest variation in the age of cracking with thicker specimens cracking at a later age. Acoustic emission testing has been used to illustrate that specimen boundary condition substantially influence crack development and propagation in the restrained rings.  相似文献   
59.
Encapsulation of Ganciclovir in lipophilic vesicular structure may be expected to enhance the oral absorption and prolong the existence of the drug in the systemic circulation. So the purpose of the present study was to improve the oral bioavailability of Ganciclovir by preparing nanosized niosomal dispersion. Niosomes were prepared from Span40, Span60, and Cholesterol in the molar ratio of 1:1, 2:1, 3:1, and 3:2 using reverse evaporation method. The developed niosomal dispersions were characterized for entrapment efficiency, size, shape, in vitro drug release, release kinetic study, and in vivo performance. Optimized formulation (NG8; Span60:Cholesterol 3:2 molar ratio) has shown a significantly high encapsulation of Ganciclovir (89±2.13%) with vesicle size of 144±3.47 nm (polydispersity index [PDI]=0.08). The in vitro release study signifies sustained release profile of niosomal dispersions. Release profile of prepared formulations have shown that more than 85.2±0.015% drug was released in 24 h with zero-order release kinetics. The results obtained also revealed that the types of surfactant and Cholesterol content ratio altered the entrapment efficiency, size, and drug release rate from niosomes. In vivo study on rats reveals five-time increment in bioavailability of Ganciclovir after oral administration of optimized formulation (NG8) as compared with tablet. The effective drug concentration (>0.69 μg/mL in plasma) was also maintained for at least 8 h on administration of the niosomal formulation. In conclusion, niosomes can be proposed as a potential oral delivery system for the effective delivery of Ganciclovir.  相似文献   
60.
Multimedia Tools and Applications - Epilepsy is a neurological disorder causing abnormal activities in the brain such as seizures, unusual behavior, sensations and loss of awareness. This disorder...  相似文献   
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