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81.
To ameliorate diabetes mellitus-associated heart failure with preserved ejection fraction (HFpEF), we plan to lower diabetes-mediated oxidative stress-induced 4-hydroxy-2-nonenal (4HNE) accumulation by pharmacological agents that either decrease 4HNE generation or increase its detoxification.A cellular reactive carbonyl species (RCS), 4HNE, was significantly increased in diabetic hearts due to a diabetes-induced decrease in 4HNE detoxification by aldehyde dehydrogenase (ALDH) 2, a cardiac mitochondrial enzyme that metabolizes 4HNE. Therefore, hyperglycemia-induced 4HNE is critical for diabetes-mediated cardiotoxicity and we hypothesize that lowering 4HNE ameliorates diabetes-associated HFpEF. We fed a high-fat diet to ALDH2*2 mice, which have intrinsically low ALDH2 activity, to induce type-2 diabetes. After 4 months of diabetes, the mice exhibited features of HFpEF along with increased 4HNE adducts, and we treated them with vehicle, empagliflozin (EMP) (3 mg/kg/d) to reduce 4HNE and Alda-1 (10 mg/kg/d), and ALDH2 activator to enhance ALDH2 activity as well as a combination of EMP + Alda-1 (E + A), via subcutaneous osmotic pumps. After 2 months of treatments, cardiac function was assessed by conscious echocardiography before and after exercise stress. EMP + Alda-1 improved exercise tolerance, diastolic and systolic function, 4HNE detoxification and cardiac liver kinase B1 (LKB1)-AMP-activated protein kinase (AMPK) pathways in ALDH2*2 mice with diabetes-associated HFpEF. This combination was even more effective than EMP alone. Our data indicate that ALDH2 activation along with the treatment of hypoglycemic agents may be a salient strategy to alleviate diabetes-associated HFpEF.  相似文献   
82.
An experimental study examining thermal contact resistance and total resistance of metal (SS304)/silicone rubber/SS304 joint under light loads (0.02 to 0.25 MPa of apparent stress) for the different heat flux inputs (2.4 to 8.6 kW/m2) has been carried out. The bulk resistance of the 4.76 mm thick elastomer specimen accounted for between 65 to 70% of the total resistance, depending upon the applied conditions. A high thermal rectification was observed, that is, contact resistance at the hot interface was approximately 1.3 to 1.6 times higher than the contact resistance at the cold interface. The mean temperature at the interface and heat flux were found more influencing parameters than the apparent stress.  相似文献   
83.
Nb-20Mo-15Si-25Cr (25Cr alloy) and Nb-20Mo-15Si-25Cr-5B (25Cr/5B alloy) alloys have been subjected to oxidation in air for 24 hours from 973 K to 1673 K (700 °C to 1400 °C). Even though B additions do not improve oxidation resistance at temperatures higher than 1473 K (1200 °C), the lower temperature oxidation resistance is superior with B by influencing the microstructure. Porous oxide scale development at lower temperatures has been attributed to the dominant growth of Nb2O5 and the vaporization of MoO3. An intermediate oxidation layer is developed between the scale and the metal for the 25Cr/5B alloy at temperatures above 1173 K (900 °C). Scale densification at elevated temperatures results in higher stress development as a result of the mismatch of coefficients of thermal expansion, ultimately resulting in oxide spallation.  相似文献   
84.
Localization is an unavoidable procedure in location aware sensor networks. In such networks, management of a large amount of location information along with its processing and updating is highly desirable at a central station of the network. In this paper, we have discussed the implementation of software layer to be run on various types of sensor nodes in the localization network, which has been dealt with extensively along with some of the addressed problems and their respective solutions. In addition, the article discusses implementation of an already mathematical formulation of least squares trilateration, which has not yet been attempted in the space of wireless sensor networks. To support our clam we performed experimental analysis on \(telosb\) motes. Experimental results of proposed framework shows that average error with respect to the physical location estimation can be reduced upto 46.66 % using 4 anchor node as compare to three anchor nodes at outdoor scenario and upto 40 % in indoor scenario.  相似文献   
85.
Cultivars with efficient root systems play a major role in enhancing resource use efficiency, particularly water absorption, and thus in drought tolerance. In this study, a diverse wheat association panel of 136 wheat accessions including mini core subset was genotyped using Axiom 35k Breeders’ Array to identify genomic regions associated with seedling stage root architecture and shoot traits using multi-locus genome-wide association studies (ML-GWAS). The association panel revealed a wide variation of 1.5- to 50-fold and were grouped into six clusters based on 15 traits. Six different ML-GWAS models revealed 456 significant quantitative trait nucleotides (QTNs) for various traits with phenotypic variance in the range of 0.12–38.60%. Of these, 87 QTNs were repeatedly detected by two or more models and were considered reliable genomic regions for the respective traits. Among these QTNs, eleven were associated with average diameter and nine each for second order lateral root number (SOLRN), root volume (RV) and root length density (RLD). A total of eleven genomic regions were pleiotropic and each controlled two or three traits. Some important candidate genes such as Formin homology 1, Ubiquitin-like domain superfamily and ATP-dependent 6-phosphofructokinase were identified from the associated genomic regions. The genomic regions/genes identified in this study could potentially be targeted for improving root traits and drought tolerance in wheat.  相似文献   
86.
In the present work, sol–gel method is used to synthesize TiO2 nanoparticle. The characterization of the prepared TiO2 powder is done using Powder X-ray diffraction (powder XRD), Scanning Electron Microscope (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS) and Ultraviolet-Visible Spectrophotometry (UV-Vis). The XRD pattern reveals formation of anatase phase TiO2. The SEM images reveal agglomeration of nanoparticles. The absorbance spectrum of TiO2 nanoparticles was observed with excitonic peaks at 327 nm and the band gap came out to be ~3.2 eV. This prepared TiO2 was tested for photovoltaic performance by using it in the Dye sensitized solar cell (FTO/TiO2/N719/KI-I2/Pt). Conversion of solar light energy to electricity was successfully done using this TiO2. The fabricated cell showed an open-circuit voltage (V OC) of 587 mV and short-circuit current density (J SC) of 5.06 mA/cm2. Maximum power (P max) generated was 1.912 mW/cm2 with a fill factor (FF) of 0.644 and a conversion efficiency of 1.91%.  相似文献   
87.
An indigenously isolated strain of Bacillus sphaericus was found to produce 1.21 IU/ml of tannase under unoptimized conditions. Optimizing the process one variable at a time resulted in the production of 7.6 IU/ml of tannase in 48 h in the presence of 1.5% tannic acid. A 9.26-fold increase in tannase production was achieved upon further optimization using response surface methodology (RSM), a statistical approach. This increase led to a production level of 11.2I U/ml in medium containing 2.0% tannic acid, 2.5% galactose, 0.25% ammonium chloride, and 0.1% MgSO(4) pH 6.0 incubated at 37°C and 100 rpm for 48 h with a 2.0% inoculum level. Scaling up tannase production in a 30-l bioreactor resulted in the production of 16.54 IU/ml after 36 h. Thus far, this tannase production is the highest reported in this bacterial strain. Partially purified tannase exhibited an optimum pH of 5.0 with activity in the pH range of 3 to 8; 50°C was the optimal temperature for activity. Efficient conversion of tannic acid to purified gallic acid (90.80%) was achieved through crystallization.  相似文献   
88.
“Sequential pattern mining” is a prominent and significant method to explore the knowledge and innovation from the large database. Common sequential pattern mining algorithms handle static databases. Pragmatically, looking into the functional and actual execution, the database grows exponentially thereby leading to the necessity and requirement of such innovation, research, and development culminating into the designing of mining algorithm. Once the database is updated, the previous mining result will be incorrect, and we need to restart and trigger the entire mining process for the new updated sequential database. To overcome and avoid the process of rescanning of the entire database, this unique system of incremental mining of sequential pattern is available. The previous approaches, system, and techniques are a priori-based frameworks but mine patterns is an advanced and sophisticated technique giving the desired solution. We propose and incorporate an algorithm called STISPM for incremental mining of sequential patterns using the sequence tree space structure. STISPM uses the depth-first approach along with backward tracking and the dynamic lookahead pruning strategy that removes infrequent and irregular patterns. The process and approach from the root node to any leaf node depict a sequential pattern in the database. The structural characteristic of the sequence tree makes it convenient and appropriate for incremental sequential pattern mining. The sequence tree also stores all the sequential patterns with its count and statistics, so whenever the support system is withdrawn or changed, our algorithm using frequent sequence tree as the storage structure can find and detect all the sequential patterns without mining the database once again.  相似文献   
89.
The solid state photo-electrochemical cell (PEC) solar energy conversion devices based on pure PPAT and PPAT:TY blend has been fabricated having structure ITO/nc-ZnO/PPAT or PPAT:TY/electrolyte/PEDOT:PSS-ITO and characterized. The redox properties of PPAT and TY were characterized using cyclic voltammetery (CV). The energy levels of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) have been estimated from their CV and UV–vis absorption spectra. The PPAT and PPAT:TY were used as sensitizer for ZnO nano-particle (nc-ZnO) in the film of PEC devices. Device that consist of PPAT:TY/nc-ZnO photoactive electrode showed improved photovoltaic performance over that consist of PPAT/nc-ZnO. This improvement attributed to the formation bulk heterojunction between PPAT and TY resulting efficient exciton dissociation into free charge carrier and photoinduced charge transfer. The photovoltaic performance of the device is further enhanced when the annealed PPAT:TY blend is used as sensitizer, which attributed to the increase in absorption and red shift in the absorption peak upon thermal annealing. This effect is due to the increased crystallinity of PPAT in the blend. PEC assembling with nc-ZnO adsorbed PPAT:TY blend using polar solvent treated PEDOT:PSS coating on ITO as a counter electrode, was studied. It was observed that when DMSO treated PEDOT:PSS counter electrode is used, the photovoltaic performance of the device is highest, which is attributed to enhanced conductivity of PEDOT:PSS and increased surface roughness. The PEC using carbon black (0.2 wt.%) modified DMSO treated PEDOT:PSS counter electrode reached a device efficiency of 5.54% under illumination 10 mW/cm2. This efficiency is higher than a PEC using untreated PEDOT:PSS as counter electrode. The thermal annealing of nc-ZnO photoelectrode improves the power conversion efficiency of the device, attributed to the increase crystallinity of the ZnO.  相似文献   
90.
Climate change is one of the most significant challenges faced by societies this century. Energy consumption is directly associated with CO2 emissions and climate change. The European Commission has set out emission reduction targets that require a great deal of energy consumption savings in the next 10 years in European countries. This paper presents the results of an analysis of the potential cost-effectiveness of different policy options aimed to foster the production and consumption of energy-efficient appliances in different European countries. Our results suggest that incentives to promote the use of energy-efficient appliances can be cost-effective, but whether or not they are depends on the particular country and the options under consideration. From the cases considered, tax credits on boilers appear to be a cost-effective option in Denmark and Italy, while subsidies on CFLi bulbs in France and Poland are cost-effective in terms of €/ton of CO2 abated. Comparing the subsidies against the energy tax options, we find that the subsidies are in most cases less cost-effective than the energy tax.  相似文献   
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