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201.
Sara Becerril Roberto Corchado-Cobos Natalia García-Sancha Leonor Revelles David Revilla Tatiana Ugalde Concepcin Romn-Curto Jesús Prez-Losada Javier Caueto 《International journal of molecular sciences》2021,22(10)
Advances in virology and skin cancer over recent decades have produced achievements that have been recognized not only in the field of dermatology, but also in other areas of medicine. They have modified the therapeutic and preventive solutions that can be offered to some patients and represent a significant step forward in our knowledge of the biology of skin cancer. In this paper, we review the viral agents responsible for different types of skin cancer, especially for solid skin tumors. We focus on human papillomavirus and squamous cell cancers, Merkel cell polyomavirus and Merkel cell carcinoma, and human herpesvirus 8 and Kaposi’s sarcoma. 相似文献
202.
Effect of Grain Thermal Expansion Mismatch on Thermal Conductivity of Porous Ceramics 总被引:1,自引:0,他引:1
Efim Litovsky Tatiana Gambaryan-Roisman Michael Shapiro Artur Shavit 《Journal of the American Ceramic Society》1999,82(4):994-1000
Many ceramics contain microcracks, which are often situated between sintered grains. These microcracks constitute thermal resistances, which may affect heat transfer through the material and its effective thermophysical properties. The thicknesses and the contact areas of the microcracks change with temperature as a result of the thermal expansion mismatch between the grains on opposite sides of the microcracks. This physical mechanism affects changes of the material's thermal conductivity, k , with temperature. The above mechanism usually plays a minor role at atmospheric pressure, where heat may flow via the gas filling the cracks. Hence, the temperature-induced changes of the crack geometry have little effect on heat transfer. However, at low gas pressures, where the heat flow between the grains occurs mainly via the contact areas, the grains' thermal expansion mismatch causes unusual temperature behavior of the material's thermal conductivity observed for several industrial refractories. In this paper, the influence of the above physical mechanism is discussed relative to other heat transfer mechanisms described in the literature. A simple physical model of the thermal expansion of grains bonded by an agent, having different thermal expansion coefficients, is developed. This model allows calculation of the contact area and the average microcrack opening between the grains as functions of the temperature, the characteristic grains sizes and their thermal expansion coefficients, and the permanent crack area. These parameters are evaluated and used to calculate the effective thermal conductivity of ceramic materials containing microcracks that appear as a result of thermal contraction of grains. The calculated thermal conductivity satisfactorily correlates with the experimental data collected for several chrome-magnesite refractories over a wide range of temperatures and gas pressures. 相似文献
203.
Whisman Mark A.; Uebelacker Lisa A.; Settles Tatiana D. 《Canadian Metallurgical Quarterly》2010,24(3):367
Mechanisms by which poor relationship functioning contributes to poor health are not fully understood. We conducted a study to evaluate the association between marital distress and the metabolic syndrome (MetS), which refers to a clustering of characteristics that have individually been shown to be associated with elevated risk of cardiovascular disease and diabetes and which collectively have been shown to increase risk for cardiovascular disease, diabetes, stroke, and mortality. A population-based English sample of couples (N = 671 couples) in which both partners were between the ages of 52 and 79 years old completed a self-report measure of marital distress and a nurse visit that included collection of blood pressure, blood samples, and anthropometric measures. Results indicated that for women, after controlling for demographic variables, greater marital distress was significantly associated with increasing likelihood of meeting criteria for the MetS and with the individual MetS criteria of elevated blood pressure and elevated fasting glucose. The association between marital distress and the MetS remained significant for women when additionally controlling for depressive symptoms and health habits (smoking status, physical activity). Marital distress was not significantly associated with the MetS or any of the individual MetS criteria for men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
204.
Marco A. Z. dos Santos Tatiana V. R. Alicieo Claudio M. P. Pereira Guillermo Ramis-Ramos Carla R. B. Mendonça 《Journal of the American Oil Chemists' Society》2014,91(1):19-27
The influence of different procedures of pulp drying and oil extraction methods on the concentrations of α-tocopherol, squalene and several phytosterols in avocado oil was evaluated. Pulp portions of Fortune variety avocados were dried either by lyophilization or under circulating air at 40 or 70 °C. For lyophilization and for each air drying temperature, the oil was obtained either by cold pressing or with Soxhlet extraction using petroleum ether. The dehydrated pulp (73 % of the pulp weight) yielded 25–33 % oil by cold pressing, and 45–57 % oil by Soxhlet extraction. Infrared spectroscopy and gas chromatography with FID and mass spectrometry detection were used to analyze the oils. α-Tocopherol, squalene, cycloartenol acetate, β-sitosterol, campesterol and stigmasterol were present in all the oil samples. In comparison to lyophilization, hot air drying resulted in smaller concentrations of α-tocopherol, squalene and β-sitosterol, and larger relative concentrations of campesterol and cycloartenol acetate. On the other hand, extraction by cold pressing produced a smaller amount of oil, with greater concentrations of α-tocopherol and squalene, and lower contents of campesterol and cycloartenol acetate, than Soxhlet extraction. Thus, the oil yield was maximal with lyophilization and Soxhlet extraction, but lyophilization and cold pressing produced oils which had greater concentrations of antioxidants and other bioactive compounds. 相似文献
205.
Biocompatible and biodegradable alginate/poly(N‐isopropylacrylamide) hydrogels for sustained theophylline release
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Raluca Petronela Dumitriu Ana‐Maria Oprea Catalina Natalia Cheaburu Manuela‐Tatiana Nistor Ovidiu Novac Cristina Mihaela Ghiciuc Lenuta Profire Cornelia Vasile 《应用聚合物科学杂志》2014,131(17)
Mixed‐interpenetrated polymeric networks based on sodium alginate (ALG) and poly(N‐isopropylacryl amide) (PNIPAAm) covalently cross‐linked with N,N'‐methylenebisacrylamide are studied for their biocompatibility, nontoxicity, and biodegradability aiming their application in drug delivery. The presence of drug‐polymeric matrix interactions and the distribution of the drug in the polymeric network for theophylline‐loaded ALG/PNIPAAm hydrogels are also investigated by spectroscopic and microscopic methods. The quantitative evaluation of theophylline loaded hydrogels performed by NIR‐CI technique shows a better drug entrapment and a higher homogeneity of the samples with increased alginate content. The thermal behavior of the hydrogels is significantly modified by theophylline presence. The application of the ALG/PNIPAAm hydrogels as carriers for sustained drug release formulations was assessed by the theophylline release tests performed both by in vitro and in vivo studies. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40733. 相似文献
206.
Vertically aligned multiwalled carbon nanotubes (MWCNTs) have been synthesised on Ni coated single crystal diamond substrates using a glow-discharge technique. A mixture of gases including CH4, H2 and N2 has been used for growth. The effect of the CH4/H2 gas mixture and growth temperature on the structure and yield of the MWCNTs has been studied. Atomic force microscopy is used to characterise the annealed Ni film prior to growth. Scanning electron microscope studies have also been carried out to observe the yield, height and diameter of MWCNTs produced under various experimental conditions. Raman spectroscopy has been performed to provide quantitive information on the crystallinity of our as-grown MWCNTs. It has been shown that highly adherent, vertically aligned MWCNTs can be grown on type Ib diamond (100) substrates with an interface free from metal catalyst. 相似文献
207.
Fast and efficient metrology tools are required in microelectronics for control of ever-decreasing feature sizes. Optical techniques such as spectroscopic ellipsometry (SE) and normal incidence reflectometry are widely used for this task. In this work we investigate the potential of spectral Mueller polarimetry in conical diffraction for the characterization of 1D gratings, with particular emphasis on small critical dimensions (CDs). Mueller matrix spectra were taken in the visible (450-700 nm) wavelength range on a photoresist grating on a Si substrate with 70/240 nm CD/period nominal values, set at nine different azimuthal angles. These spectra were fitted with a rigorous coupled-wave analysis (RCWA) algorithm by using different models for the grating profile (rectangular and trapezoidal, with or without rounded corners). A detailed study of the stability and consistency of the optimal CD values, together with the variation of the merit function (the mean square deviation D2) around these values, clearly showed that for a given wavelength range, this technique can decouple some critical parameters (e.g., top and bottom CDs, left and right sidewall projections) much more efficiently than the usual SE. 相似文献
208.
We present a theoretical approach enabling one to perform a preproduction investigation of the effect of accumulation of thickness errors in the course of optical coating production using broadband optical monitoring. On the basis of this approach we investigate and compare thickness errors that may be associated with such factors as random and systematic errors in measurement data, instabilities of deposition rates, and inaccuracies of on-line algorithms predicting termination instants for layer depositions. 相似文献
209.
Diana Ansorena Ainhoa Guembe Tatiana Mendizábal Iciar Astiasarán 《Journal of food science》2010,75(2):H62-H67
ABSTRACT: The modifications on a lean fish (cod—Gadus morhua) and a fatty fish (farmed salmon—Salmo salar) after the application of pan-frying using 2 types of oil with different lipid profile (extra virgin olive oil and sunflower oil) was the aim of this study. Fat content and total energetic value increased significantly after the frying process only in the lean fish, without relevant changes in the fatty fish. Extra virgin olive oil led to a higher fat absorption rate than sunflower oil in both fish. Frying hardly affected the lipid profile of farmed salmon regardless the oil used, however it drastically changed in fried cod compared to raw cod. Omega-6/omega-3 ratio increased from 0.08 in raw cod to 1.01 and 6.63 in fried cod with olive oil and sunflower oil, respectively. In farmed salmon, the omega-6/omega-3 ratio was 0.38 (raw), and 0.39 to 0.58 in fried salmon. The amount of EPA + DHA slightly decreased with frying in salmon, and increased in cod. The type of oil has more influence in the nutritional fish quality for the lean fish compared to that of the fatty fish. The use of extra virgin olive oil was efficient to avoid a significant increase of the lipid oxidation intensity during frying in cod but not in salmon. Practical Application: Food modifies its composition and nutritional value with the application of cooking technologies. As most food table composition tables are based on raw food products, this article contributes with interesting data on pan-fried fish composition, which may improve the approach to achieve a real intake of healthy nutrients as omega 3 fatty acids. 相似文献