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排序方式: 共有574条查询结果,搜索用时 15 毫秒
71.
Katie Rubitschung Amber Sherwood Andrew P. Crisologo Kavita Bhavan Robert W. Haley Dane K. Wukich Laila Castellino Helena Hwang Javier La Fontaine Avneesh Chhabra Lawrence Lavery Orhan K.
z 《International journal of molecular sciences》2021,22(21)
Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host’s immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections. 相似文献
72.
Quantitative analysis of textile blends and textile fabrics is currently of particular interest in the industrial context. In this frame, this work investigates whether the use of Fourier transform (FT) near-infrared (NIR) spectroscopy and chemometrics is powerful for rapid and accurate quantitative analysis of cotton-polyester content in blend products. As samples of the same composition have many sources of variability that affect NIR spectra, indirect prediction is particularly challenging and a large sample population is required to design robust calibration models. Thus, a total of more than three-hundred cotton-polyester samples were selected covering the range from the 0% to 100% cotton and the corresponding NIR reflectance spectra were measured on raw fabrics. The data set obtained was used to develop multivariate models for quantitative prediction from reference measurements. A successful approach was found to rely on partial least squares (PLS) regression combined with genetic algorithms (GAs) for wavelength selection. It involved evaluating a set of calibration models considering different spectral regions. The results obtained considering 27.5% of the original variables yielded a prediction error (RMSEP) of 2.3 in percent cotton content. It demonstrates that FT-NIR spectroscopy has the potential to be used in the textile industry for the prediction of the composition of cotton-polyester blends. As a further consequence, it was observed that the spectral preprocessing and the complexity of the model are simplified compared to the full-spectrum approach. Also, the relevancy of the spectral intervals retained after variable selection can be discussed. 相似文献
73.
Mehmet F. Orhan Ibrahim Dincer Marc A. Rosen Mehmet Kanoglu 《Renewable & Sustainable Energy Reviews》2012,16(8):6059-6082
Due to varied global challenges, potential energy solutions are needed to reduce environmental impact and improve sustainability. Many of the renewable energy resources are of limited applicability due to their reliability, quality, quantity, and density. Thus, the need remains for additional sustainable and reliable energy sources that are sufficient for large-scale energy supply to complement and/or back up renewable energy sources. Nuclear energy has the potential to contribute a significant share of energy supply with very limited impacts to global climate change. Hydrogen production via thermochemical water decomposition is a potential process for direct utilization of nuclear thermal energy. Nuclear hydrogen and power systems can complement renewable energy sources by enabling them to meet a larger extent of global energy demand by providing energy when the wind does not blow, the sun does not shine, and geothermal and hydropower energies are not available. Thermochemical water splitting with a copper–chlorine (Cu–Cl) cycle could be linked with nuclear and selected renewable energy sources to decompose water into its constituents, oxygen and hydrogen, through intermediate copper and chlorine compounds. In this study, we present an integrated system approach to couple nuclear and renewable energy systems for hydrogen production. In this regard, nuclear and renewable energy systems are reviewed to establish some appropriate integrated system options for hydrogen production by a thermochemical cycle such as Cu–Cl cycle. Several possible applications involving nuclear independent and nuclear assisted renewable hydrogen production are proposed and discussed. Some of the considered options include storage of hydrogen and its conversion to electricity by fuel cells when needed. 相似文献
74.
Hakan Çolak Orhan Türkoğlu 《Journal of Materials Science: Materials in Electronics》2012,23(9):1750-1758
This paper reports the synthesis, crystal structure and electrical conductivity properties of vanadium (V)-doped zinc oxide (ZnO) powders (i.e. Zn1?2X V X O binary system, x = 0, 0.0025, 0.005, 0.0075 and in the range 0.01 ≤ x ≤ 0.15). I-phase samples, which were indexed as single phase with a hexagonal (wurtzite) structure in the V-doped ZnO binary system, were determined by X-ray diffraction (XRD). The limit solubility of V in the ZnO lattice at this temperature is 3 mol % at 950 °C. The impurity phase at 950 °C was determined as ZnV2O6 when compared with standart XRD data. The research focused on single I-phase ZnO samples which were synthesized at 950 °C because of the limit of the solubility range is widest at this temperature. It was observed that the lattice parameters a and c decreased with V doping concentration. The electrical conductivity of the pure ZnO and single I-phase samples were studied using the four-point probe dc method at temperatures between 100 and 950 °C in an air atmosphere. The electrical conductivity values of pure ZnO and 3 mol % V-doped ZnO samples at 100 °C were 2.75 × 10?6 and 7.94 × 10?5 Ω?1 cm?1, and at 950 °C they were 3.4 and 54.95 Ω?1 cm?1, respectively. In other words, the electrical conductivity increased with V doping concentration. 相似文献
75.
E. Tel A. Kaplan A. Aydın S. Özkorucuklu H. Büyükuslu G. Yıldırım 《Journal of Fusion Energy》2010,29(4):312-316
Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology,
there is still a long way to go to penetrate commercial fusion reactors to the energy market. Tritium self-sufficiency must
be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater
than 1.05. So, working out the systematics of (n,t) reaction cross sections and triton emission differential data are important for the given reaction taking place on various
nuclei at different energies. In this study, (n,xt) reactions for some target nuclei as 16O, 27Al, 59Co and 209Bi have been investigated up to 45 MeV incident neutron energy. In the calculations of the triton emission spectra, the pre-equilibrium
and equilibrium effects have been used. The calculated results have been compared with the experimental data taken from the
literature. 相似文献
76.
The use of optical measurement equipment and software based on photogrammetry is becoming more affordable and is increasing their reliability in presenting results on surfaces topography as well as strain distribution. The question is, how feasible can their support be to the process/product development engineer in the choice of the right auto body-in-white (BIW) component design; how can they influence blank and tool geometries, process parameters and moreover the right material selection, in order to reduce the springback of such materials on drawing, reaching the required quality standards for the part. This paper describes some industrial cases on how these new techniques can be applied to lay out industrial deep drawing processes, accomplished by the use of optical measurement, improving design and process issues. 相似文献
77.
Ensuring the effective thermal insulation in regions, where the cooling requirement of building with respect to heating requirement is dominant, is very important from the aspect of energy economy. In this study, the influence of thermal insulation on the building cooling load and the cooling system in case of air-conditioning by an all-air central air-conditioning system was evaluated for a sample building located in Adana, based on the results of three different types of insulation (A, B and C-type buildings) according to the energy efficiency index defined in the Thermal Insulation Regulation used in Turkey. The operating costs of the air-conditioning system were calculated using cooling bin numbers. Life-cycle cost analysis was carried out utilizing the present-worth cost method. Results showed that both the initial and the operating costs of the air-conditioning system were reduced considerably for all three insulation thicknesses. However, the optimum results in view of economic measurements were obtained for a C-type building. The thickness of thermal insulation for the buildings in the southern Turkey should be determined according to the guidelines for a C-type building. 相似文献
78.
Hilal Kivrak Dilan Atbas Orhan Alal M. Selim Çögenli Ayse Bayrakceken Suha Orcun Mert Ozlem Sahin 《International Journal of Hydrogen Energy》2018,43(48):21886-21898
At present, Pd containing (10–40 wt%) multiwall carbon nanotube (MWCNT) supported Pd monometallic, Pd:Au bimetallic, and PdAuCo trimetallic catalysts are prepared via NaBH4 reduction method to examine their formic acid electrooxidation activities and direct formic acid fuel cell performances (DFAFCs) when used as anode catalysts. These catalysts are characterized by advanced analytical techniques as N2 adsorption and desorption, XRD, SAXS, SEM-EDX, and TEM. Electronic state of Pd changes by the addition of Au and Co. Moreover, formic acid electrooxidation activities of these catalysts measured by CV indicates that particle size changes in wide range play a major role in the formic acid electrochemical oxidation activity, ascribed the strong structure sensitivity of formic acid electrooxidation reaction. PdAuCo (80:10:10)/MWCNT catalyst displays the most significant current density increase. On the other hand, lower CO stripping peak potential obtained for PdAuCo (80:10:10)/MWCNT catalyst, attributed to the awakening of the Pd-adsorbate bond strength down to its optimum value, which favors higher electrochemical activity. DFAFCs performance tests and exergy analysis reveal that fuel cell performances increase with the addition of Au and Co which can be attributed to synergetic effect. Furthermore, temperature strongly influences the performance of formic acid fuel cell. 相似文献
79.
Sezen Tekin H. Gul Yaglioglu Ayhan Elmali Ulaş Kürüm Hülya Yanık Duygu Aydın Tekdaş Mahmut Durmuş Vefa Ahsen 《Materials Chemistry and Physics》2013
The nonlinear optical properties (NLO) of Pcs can be modified by substituting different metal atoms into the ring or altering peripheral and axial functionalities. In this study, nonlinear optical absorption properties of tetra-substituted gallium and indium phthalocyanine complexes both in solution and polymeric film have been investigated by open aperture Z-scan measurements with nanosecond pulses at 532 nm. All investigated compounds exhibited reverse saturable absorption for both solution and film experiments. The investigated compounds in the solution showed better nonlinear optical absorption properties than polymeric films. The observed nonlinear optical absorption differences depending on the aggregation are discussed using the ultrafast dynamics and decay processes of excited states found from femtosecond pump-probe spectroscopy with white light continuum experiments. 相似文献
80.
S. H. Aydın 《Numerical Heat Transfer, Part A: Applications》2013,63(10):799-813
The present numerical study deals with the stabilized finite element solution of the steady natural convection flow in terms of primitive variables. The domain is discretized into a set of regular linear triangular elements for all unknowns containing a single subgrid node, which has a crucial effect in the stabilization with a cheap computational cost. The proposed stabilized finite element method enables obtainment of a stable solution and avoids oscillations, especially in the pressure. The algorithm is presented for different benchmark problems considered in different geometries and the solutions are obtained for high values of Rayleigh number (Ra) (103 ≤ Ra ≤ 106). Furthermore, the solutions show the well-known characteristics of the natural convection flow and agree well with the results in the literature. 相似文献