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31.
32.
Intramuscular connective tissue obtained from Longissimus dorsi muscle of a 4-year-old beef carcass was treated with NaCl solutions of 2, 4, and 6% (w/v), and CaCl2 solutions of 50, 100, and 150 mM, and citric and lactic acid solutions of 0.5, 1.0, and 1.5% for three different marinating periods (24, 46, and 72 h). Changes in denaturation characteristics were investigated using differential scanning calorimetry and it was found that the denaturation onset temperature (To) and the denaturation peak temperature (Tp) increased as the NaCl concentration increased but decreased as the CaCl2 concentration increased, irrespective of marinating time. Lactic and citric acid decreased To to about 39°C, from over 60°C breaking the structure of fibrils. 相似文献
33.
Oktay H. Ozturk Yesim Can Zafer Yonden Sedat Motor Gonul Oktay Hasan Kaya Mutay Aslan 《Lipids》2013,48(12):1217-1226
Although hypocholesterolemia is a reported finding in sickle cell disease (SCD), low-density lipoprotein (LDL)/high-density lipoprotein (HDL) subfractions and HDL-associated enzymes have not been determined in SCD patients. Blood was collected from 38 hemoglobin (Hb)A volunteers and 45 homozygous HbSS patients who had not received blood transfusions in the last 3 months. Serum lipids were measured by automated analyzer while LDL and HDL subfraction analysis was done by continuous disc polyacrylamide gel electrophoresis. Serum levels of cholesteryl ester transfer protein (CETP), lecithin-cholesterol acyltransferase (LCAT), apolipoprotein B (apoB) and apolipoprotein A-1 (apoA-I) were determined by enzyme-linked immunosorbent assay (ELISA). Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels were significantly decreased, while TG levels were significantly increased in SCD patients compared to controls. A significant decrease in intermediate-density lipoprotein (IDL)-C, IDL-B, IDL-A and LDL-1 fractions were seen in SCD patients, while no significant difference was observed in small dense LDL particles. A significant decrease was seen in HDL-large, HDL-intermediate and HDL-small fractions in SCD patients versus controls. Levels of LCAT and ApoA-1 protein measured in SCD patients were significantly lower while no significant difference was observed in CETP and ApoB protein levels compared to controls. The reduction observed in LDL- and HDL-C in SCD patients was reflected as significantly decreased IDL, LDL-1 and HDL-subfractions. Decreased HDL subfractions may possibly lead to the reduced ApoA-1 and LCAT protein levels observed in SCD patients. 相似文献
34.
Kotaka A Bando H Kaya M Kato-Murai M Kuroda K Sahara H Hata Y Kondo A Ueda M 《Journal of Bioscience and Bioengineering》2008,105(6):622-627
Three beta-glucosidase- and two endoglucanase-encoding genes were cloned from Aspergillus oryzae, and their gene products were displayed on the cell surface of the sake yeast, Saccharomyces cerevisiae GRI-117-UK. GRI-117-UK/pUDB7 displaying beta-glucosidase AO090009000356 showed the highest activity against various substrates and efficiently produced ethanol from cellobiose. On the other hand, GRI-117-UK/pUDCB displaying endoglucanase AO090010000314 efficiently degraded barley beta-glucan to glucose and smaller cellooligosaccharides. GRI-117-UK/pUDB7CB codisplaying both beta-glucosidase AO090009000356 and endoglucanase AO090010000314 was constructed. When direct ethanol fermentation from 20 g/l barley beta-glucan as a model substrate was performed with the codisplaying strain, the ethanol concentration reached 7.94 g/l after 24 h of fermentation. The conversion ratio of ethanol from beta-glucan was 69.6% of the theoretical ethanol concentration produced from 20 g/l barley beta-glucan. These results showed that sake yeast displaying A. oryzae cellulolytic enzymes can be used to produce ethanol from cellulosic materials. Our constructs have higher ethanol production potential than the laboratory constructs previously reported. 相似文献
35.
Esin Kaya Nevin Turan Bayram Gündüz Naki Çolak Hanifi Körkoca 《Polymer Engineering and Science》2012,52(7):1581-1589
The oxidative polycondensation reaction conditions of 2‐(2‐hydroxybenzylideneamino)‐6‐phenyl‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile were examined. The magnitude of the reflectance of the polymer decreases sharply with increasing of wavelength up to 524 nm, then reflectance of the polymer increases slowly with increasing of wavelength. The refractive index values of the polymer vary from 1.474 to 2.350. The Ep and Ed values of the polymer were found to be 4.56 and 7.068 eV, respectively. Absorption coefficient K of the polymer is of the order 817.062–1434.77 m?1. Angle values of incidence and refraction of the polymer vary from 57.36 to 66.95° and from 23.05 to 32.65°, respectively. The film‐phase thickness of the polymer increases with increasing photon energy. The thickness, d, of the polymer was of the order 439.3–4184.7 Å for 190 and 1100 nm, respectively. The real part of dielectric constant of the polymer decreases slowly with increasing of frequency up to about 600 THz, then the real part of dielectric constant of the polymer increases sharply with increasing of frequency. The real and imaginary parts of dielectric constant of the polymer vary from 2.17 to 5.52 and from 5.81 × 10?5 to 3.58 × 10?4, respectively. Finally, polymer was tested for antibacterial activities against some bacteria. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers 相似文献
36.
A Monte Carlo simulation based algorithm is developed to compute the effective diffusivity of lead free solder alloys. Simulations are performed to determine the vacancy diffusivity for 95.5Sn–4.0Ag–0.5Cu (SAC405) solder alloy for different paths. Temperature and micro-structural influence on diffusivity are studied. A map of diffusivity versus temperature and average grain size is developed. Significant differences between diffusivity values reported in the literature for the same solder alloy is also discussed. 相似文献
37.
Environmental impact assessment (EIA) is the assessment of the possible impact that a proposed plan or project may have on the environment, together consisting of the natural, social and economic aspects. The aim of this paper is to propose an environmental impact assessment methodology based on an integrated fuzzy AHP–ELECTRE approach in the context of urban industrial planning. In the proposed methodology the criteria weights are generated by a fuzzy AHP procedure. The fuzzy set theory is a perfect means for modeling uncertainty or imprecision arising from human mental phenomena. The usage of fuzzy sets in describing uncertainties and vagueness in different environmental factors simplifies the complex structure of EIA. A fuzzy outranking methodology, fuzzy ELECTRE is used to assess the environmental impact generated by the six different industrial districts which were predicted to shape the future industrial structure of Istanbul metropolitan area. Finally, a fuzzy dominance relation (FDR) methodology is used to rank the alternatives from the most risky to the least. A sensitivity analysis is also provided. 相似文献
38.
Hard-sphere molecular dynamics simulations of lid-driven microcavity gas flow with various subsonic speeds and lid temperatures are conducted. Simulations with faster and colder lids show streamlines of stronger primary vortices. Variations of mass and energy centers with respect to lid speed and temperature are examined. Center of energy is less sensitive to employed lid conditions than center of gravity is. Although moving lid imparts energy into fluid, due to change of impingement rates on the walls of fixed temperature, average energy within the cavity seems quite insensitive to the subsonic lid speed. Behavior of compressibility at both top corners is observed even at low Mach numbers widely considered within incompressible flow region. While high Knudsen number causes considerable property slips near the lid, two-dimensional pressure, density, and temperature plots of excellent quality are generated. Results are promising in use of molecular dynamics simulations for compressible vortex flow analyses while providing insights for understanding microfluidics and nanofluidics in context of molecular mass, momentum and heat transfer in microscale and nanoscale systems. 相似文献
39.
40.
Tevfik Tozkoparan Emre Ulas Macit Olcer Cavit Arikan Meric Batmaz Aylin Saracoglu Goknur Murat Ozyilmaz Sevgi Kayhan Ebru Soydas Izmir Branch Archives Noyan Sancar Mehmet Yasa Guven Incirlioglu 李璠 《世界建筑》2010,(7):26-31
<正>一座建筑的性能应当如何来衡量?除了通过统治当代建筑舆论的美学、技术以及经济价值来进行描述之外,我们还能够如何来阐释一座建筑,尤其是一座致力于庇护那些渴望展现自己的艺术家的建筑?有人会问成功的表演是如何实现的,表演者是如何进行伪装的、又是如何展现自己的?根据海德格尔的理论,当我们看不到钉子的时候,铁锤的表现才是成功的;钉子本身的出现通常表明出现了问题。 相似文献