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排序方式: 共有1138条查询结果,搜索用时 62 毫秒
881.
Abhishek Pandeya Raj Kumar Khalko Anup Mishra Nishant Singh Sukhveer Singh Sudipta Saha Sanjay Yadav Sangeeta Saxena Sunil Babu Gosipatala 《International journal of molecular sciences》2022,23(1)
Human Cytomegalovirus (HCMV) is a prototypic beta herpesvirus, causing persistent infections in humans. There are medications that are used to treat the symptoms; however, there is no cure yet. Thus, understanding the molecular mechanisms of HCMV replication and its persistence may reveal new prevention strategies. HCMV evasive strategies on the antiviral responses of the human host largely rely on its significant portion of genome. Numerous studies have highlighted the importance of miRNA-mediated regulation of apoptosis, which is an innate immune mechanism that eradicates virus-infected cells. In this study, we explore the antiapoptotic role of hcmv-miR-UL70-3p in HEK293T cells. We establish that hcmv-miR-UL70-3p targets the proapoptotic gene Modulator of Apoptosis-1 (MOAP1) through interaction with its 3’UTR region of mRNA. The ectopic expression of hcmv-miR-UL70-3p mimic significantly downregulates the H2O2-induced apoptosis through the translational repression of MOAP1. Silencing of MOAP1 through siRNA also inhibits the H2O2-induced apoptosis, which further supports the hcmv-miR-UL70-3p mediated antiapoptotic effect by regulating MOAP1 expression. These results uncover a role for hcmv-miR-UL70-3p and its target MOAP1 in regulating apoptosis. 相似文献
882.
Romania is the 10th largest economy in EU-28 and also one of the fastest growing economies in the region. An end-use energy demand model is developed for Romania to assess energy requirement by sector and by end-use for 2015–2050 period. Industry would surpass residential sector as the largest final energy-consuming sector from 2035 onwards. Services sector would exhibit the fastest growth of energy consumption. Despite expected decline in country’s population, demand for electricity would grow in the future driven by increased household income and expanded services sector, which is relatively electricity intensive. Still, Romania’s per capita electricity consumption would be about half of the EU-28 average. At the end-use level, thermal processes in industry, space heating in the residential and services, and road passenger travel in transport sector would be dominant throughout the study period. Improvement of energy efficiency in the heating system exhibits the highest potential of energy saving. 相似文献
883.
This study investigated the efficacy of in-package pasteurization combined with pre-surface application of nisin and/or lysozyme to reduce and prevent the subsequent recovery and growth of Listeria monocytogenes during refrigerated storage on the surface of low-fat turkey bologna. Sterile bologna samples were treated with solutions of nisin (2 mg/ml=5000 AU/ml), lysozyme (10 mg/ml=80 AU/ml) and a mixture of nisin and lysozyme (2 mg nisin+10mg lysozyme/ml) before in-package pasteurization at 65 degrees C for 32s. In-package pasteurization resulted in an immediate 3.5-4.2 log CFU/cm(2) reduction in L. monocytogenes population for all treatments. All pasteurized treatments also resulted in a significant reduction of L. monocytogenes by 12 weeks compared to un-pasteurized bologna. In-package pasteurization in combination with nisin or nisin-lysozyme treatments was effective in reducing the population below detectable levels by 2-3 weeks of storage. Results from this study could have a significant impact for the industry since a reduction in bacterial population was achieved by a relatively short pasteurization time and antimicrobials reduced populations further during refrigerated storage. 相似文献
884.
Sunil Jagannath PATIL Arun Vithal PATIL Chandrakant Govindrao DIGHAVKAR Kashinath Shravan THAKARE Ratan Yadav BORASE Sachin Jayaram NANDRE Nishad Gopal DESHPANDE Rajendra Ramdas AHIRE 《材料科学前沿(英文版)》2015,9(1):14
This paper gives a statistical view about important contributions and advances on semiconductor metal oxide (SMO) compounds based gas sensors developed to detect the air pollutants such as liquefied petroleum gas (LPG), H2S, NH3, CO2, acetone, ethanol, other volatile compounds and hazardous gases. Moreover, it is revealed that the alloy/composite made up of SMO gas sensors show better gas response than their counterpart single component gas sensors, i.e., they are found to enhance the 4S characteristics namely speed, sensitivity, selectivity and stability. Improvement of such types of sensors used for detection of various air pollutants, which are reported in last two decades, is highlighted herein. 相似文献
885.
Sunil Goyal V. KarthikK.V. Kasiviswanathan M. ValsanK. Bhanu Sankara Rao Baldev Raj 《Materials & Design》2010
In this work, finite element analysis (FEA) of the shear punch testing is carried out to study the specimen deformation up to yielding and the results are compared and validated with experimental data for four different materials. The elastic portion of the FEA generated load–displacement curve overlaps with the corresponding experimental curve only when the fixture compliances are eliminated in experiments. Based on through thickness plasticity in the FEA study, the shear yield stress estimated at an offset of 0.15% of normalized displacement compares well with the experimentally determined shear yield strength and satisfies the von Mises yield relation σys=1.73τys. The effects of die-punch clearance and specimen thickness on shear yield strength studied using FEA are also discussed. 相似文献
886.
T.S.R.Ch. Murthy J.K. Sonber C. Subramanian R.K. Fotedar Sunil Kumar M.R. Gonal A.K. Suri 《International Journal of Refractory Metals and Hard Materials》2010
A new composite of TiB2 with CrSi2 has been prepared with excellent oxidation resistance. Dense composite pellets were fabricated by hot pressing of powder mixtures. Microstructural characterization was carried out by XRD and SEM with EDAX. Mechanical and physical properties were evaluated. Extensive oxidation studies were also carried out. A near theoretical density (99.9% TD) was obtained with a small addition of 2.5 wt.% CrSi2 by hot pressing at 1700 °C under a pressure of 28 MPa for 1 h. The microstructure of the composite revealed three distinct phases, (a) dark grey matrix of TiB2, (b) black phase – rich in Si and (c) white phase – Cr laden TiB2. Hardness and fracture toughness were measured as 29 ± 2 GPa and 5.97 ± 0.61 MPa m1/2, respectively. Crack branching, deflection and bridging mechanisms were responsible for the higher fracture toughness. With increase in CrSi2 content, density, hardness and fracture toughness values of the composite decreased. Thermo gravimetric studies revealed the start of oxidation of the composite at 600 °C in O2 atmosphere. Isothermal oxidation of these composites showed better oxidation resistance by formation of a protective oxide layer. TiO2, Cr2O3 and SiO2 phases were identified on the oxidized surface. Effects of CrSi2 content, temperature and duration of oxidation on the oxide layer formation are reported. Activation energy of the composite was calculated as ∼110 kJ/mol using Arrhenius equation. Diffusion controlled mechanism of oxidation was observed in all the composites. 相似文献
887.
D. Sunil Kumar R.S. Keshavamurthy P. Mohanakrishnan S.C. Chetal 《Nuclear Engineering and Design》2010,240(10):2972-2980
Shields around core and blankets form major part of reactor assembly in fast reactors as the incident neutron spectrum is hard with negligible thermal component and has anisotropic angular distribution. In this paper, a study is presented on the use of ferro-boron as neutron shield material in pool type fast reactors. The reference case chosen is the Prototype Fast Breeder Reactor (PFBR), a 500 MWe which is sodium cooled, pool type, mixed oxide (MOX) fuelled reactor, which is under construction at Kalpakkam, India. It is shown through 2D transport calculations, carried out using 175 neutron multigroup cross-sections, that this low cost material as shield is capable of satisfying the radiological safety criteria as well as the shields in the reference case. The secondary sodium activity and dose in steam generator building are marginally lower than the reference case. The total shield material weight will be lower by about 50 tonnes and the material cost lower by a factor 5 as compared to PFBR shields comprising of stainless steel and B4C. 相似文献
888.
Kumar A. Dubey Yatender K. Bhardwaj Chandrashekhar V. Chaudhari Kuppa S. S. Sarma Narender K. Goel Sunil Sabharwal 《Journal of Polymer Research》2011,18(1):95-103
LDPE/EVA/PCR blends having fixed percentage of PCR were prepared by melt mixing and irradiated to different radiation doses
using electron beam. Gel fraction and crosslinking density of the blends were found to increase with increase in EVA content
in the formulation, suggesting higher radiation sensitivity of EVA. The heat of mixing and polymer-polymer interaction parameter
indicated better miscibility between EVA/PCR than between LDPE/PCR and LDPE/EVA. Dynamic mechanical properties of the blends
were found to significantly vary with the variation in the EVA fraction in the blends. In the composition range studied the
storage modulus decreased from 3.8 × 108 to ∼1 × 108 Pa at strain amplitude of 5 × 10−6 m. The experimentally obtained data deviated significantly from both the series as well as parallel model. The bulk density
showed a positive deviation from additive rule. The X-ray diffraction pattern of the blends revealed reduction in the crystallinity
of LDPE on blend formation. DSC thermograms of blends did not indicate any significant shift in the melting peaks, indicating
immiscibility of LDPE and EVA domains in the presence of PCR. 相似文献
889.
Erejuwa OO Sulaiman SA Wahab MS Salam SK Salleh MS Gurtu S 《International journal of molecular sciences》2011,12(1):829-843
Hyperglycemia-induced increase in oxidative stress is implicated in diabetic complications. This study investigated the effect of metformin and/or glibenclamide in combination with honey on antioxidant enzymes and oxidative stress markers in the kidneys of streptozotocin (60 mg/kg; intraperitoneal)-induced diabetic rats. Diabetic rats were randomized into eight groups of five to seven rats and received distilled water (0.5 mL); honey (1.0 g/kg); metformin (100 mg/kg); metformin (100 mg/kg) and honey (1.0 g/kg); glibenclamide (0.6 mg/kg); glibenclamide (0.6 mg/kg) and honey (1.0 g/kg); metformin (100 mg/kg) and glibenclamide (0.6 mg/kg); or metformin (100 mg/kg), glibenclamide (0.6 mg/kg) and honey (1.0 g/kg) orally once daily for four weeks. Malondialdehyde (MDA) levels, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were significantly elevated while catalase (CAT) activity, total antioxidant status (TAS), reduced glutathione (GSH), and GSH:oxidized glutathione (GSSG) ratio was significantly reduced in the diabetic kidneys. CAT, glutathione reductase (GR), TAS, and GSH remained significantly reduced in the diabetic rats treated with metformin and/or glibenclamide. In contrast, metformin or glibenclamide combined with honey significantly increased CAT, GR, TAS, and GSH. These results suggest that combination of honey with metformin or glibenclamide might offer additional antioxidant effect to these drugs. This might reduce oxidative stress-mediated damage in diabetic kidneys. 相似文献
890.
Anant K. Ghumare Balu V. Pawar Sunil S. Bhagwat 《Journal of surfactants and detergents》2013,16(1):85-93
A series of novel cationic gemini surfactants were synthesized from corresponding amido-amines in a single step reaction. The amido-amines were obtained from long chain carboxylic acids and 3-N,N-dimethylamino-1-propyl-amine with excellent isolated yield (up to 95 %). All the synthesized quaternary ammonium compounds (QACs) were further investigated for surface active properties. The critical micelle concentration (CMC) and the effectiveness of surface tension reduction were determined. The surface tension measurements of newly synthesized gemini surfactants showed good water solubility, and low CMC values, had great efficiency in lowering the surface tension and a strong adsorption at the air/water interface than the corresponding monomeric surfactants. Further, the antibacterial activity of the synthesized QACs against both Gram-positive and Gram-negative bacteria was also investigated. 相似文献