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991.
MIROSLAV VAŘECHA DANIELA PÁCLOVÁ JIŘINA PROCHÁZKOVÁ PAVEL MATULA DUŠAN CMARKO MICHAL KOZUBEK 《Biocell》2012,36(3):121-126
Recent findings suggest that apoptotic protein apoptosis-inducing factor (AIF) may also play an important non-apoptotic function inside mitochondria. AIF was proposed to be an important component of respiratory chain complex I that is the major producer of superoxide radical. The possible role of AIF is still controversial. Superoxide production could be used as a valuable measure of complex I function, because the majority of superoxide is produced there. Therefore, we employed superoxide-specific mitochondrial fluorescence dye for detection of superoxide production. We studied an impact of AIF knockdown on function of mitochondrial complex I by analyzing superoxide production in selected cell lines. Our results show that tumoral telomerase-positive (TP) AIF knockdown cell lines display significant increase in superoxide production in comparison to control cells, while a non-tumoral cell line and tumoral telomerase-negative cell lines with alternative lengthening of telomeres (ALT) show a decrease in superoxide production. According to these results, we can conclude that AIF knockdown disrupts function of complex I and therefore increases the superoxide production in mitochondria. The distinct effect of AIF depletion in various cell lines could result from recently discovered activity of telomerase in mitochondria of TP cancer cells, but this hypothesis needs further investigation 相似文献
992.
T. Fernandes C.L.S. Ávila M.N. Pereira L.F. Ferraretto 《Journal of dairy science》2018,101(10):9052-9057
The objectives of this study were to determine (1) the effect of grinding size (1, 2, 4, and 6 mm) to determine effective ruminal disappearance (ERD); (2) the most adequate method to estimate the rapidly degradable fraction (A); (3) a time point to measure the indigestible fraction (C); and (4) the viability of using fewer time points to estimate starch fractional disappearance rate (kd) of mature corn grain. Fraction A was determined by rinsing in a bucket or washing machine, rumen immersion followed by bucket or washing machine, and water immersion for 30 min followed by bucket or washing machine. Ruminal in situ incubations were performed at 48, 72, 96, and 120 h to determine fraction C, and at 0 (washing machine), 3, 6, 12, 18, 24, and 48 h to determine the kinetics of starch disappearance. Models were used with either 2 or 3 pools and kd was determined by the linear slope of the log-transformed bag residues as a proportion of incubated samples over time. The ERD was calculated as A + B [kd/(kd + kp)], where kp is the ruminal fractional passage rate = 16.0% h?1. Data were analyzed using PROC MIXED of SAS (SAS Institute Inc., Cary, NC) with the fixed effects of run (for fraction A analysis only) method (either washing or model), grinding size, and method by grinding size interaction, with cow as a random effect. Correlation between estimates calculated using all time points or combinations of 2 and 3 time points were determined using PROC CORR. Fraction A was reduced as grinding size increased, but was not altered by washing method. Samples ground at 6 mm had greater fraction C than other grinding sizes at 48, 72, or 96 h, but not at 120 h. Model affected the slowly degradable fraction (B) values solely, but the difference was minor (0.5 percentage units). Greater fractions B and C but reduced kd and ERD were observed as grinding size increased. Based on correlation analysis the 2-pool model, incubation times of 0, 3, and 48 h were suitable to evaluate ruminal starch degradation kinetics in mature corn. Ruminal in situ incubation at 120 h highlighted the lack of a fraction C of starch (0.13% of starch). Washing method did not affect determination of fraction A of starch. Ruminal in situ incubations of 0, 3, and 48 h for starch degradation kinetics using a 2-pool model were adequate for mature ground corn, but 120 h of incubation is suggested to confirm the existence or absence of a fraction C. Grinding size affected starch degradation kinetics and fraction A determination. 相似文献
993.
Performance assessment of concentrated solar power plants based on carbon and hydrogen fuel cells 总被引:1,自引:0,他引:1
Elena Díaz Michael Epstein Manuel Romero José González-Aguilar 《International Journal of Hydrogen Energy》2018,43(11):5852-5862
In spite of the recent success on the implementation of Concentrating Solar Power (CSP), still this technology needs a substantial enhancement to achieve competitiveness. This paper provides thorough insight after previous analyses on an alternative concept for higher efficiency CSP systems based on the replacement of the power block by an electrochemical conversion system. Concentrating solar energy is herewith used to decompose methane into hydrogen and carbon, which are used in hydrogen and carbon fuel cells for electricity generation. This approach envisages modular, efficient and flexible generation plants. Dispatchability can be achieved by storing the solid carbon. Solar-to-electricity efficiency was calculated assuming thermodynamic equilibrium composition and experimental data available from literature, and compared with those of conventional power generation systems and commercial CSP plants. It is concluded that this new-generation CSP concept is potentially able to produce power more efficiently than the current state-of-the art solar thermal power plants. 相似文献
994.
Neil Stephen LOPEZ Anthony S.F. CHIU Jose Bienvenido Manuel BIONA 《Frontiers in Energy》2018,12(3):389-399
Global CO2 emissions increased by 57.9% from 1990 to 2014, of which 21% is known to be from the transportation sector. In line with policy development, driving forces to energy consumption and emissions may be determined using decomposition analysis techniques. However, the detail of information required to perform such studies for the transportation sector in developing countries can be challenging. An attempt was made in this study to formulate a decomposition analysis framework considering data availability and limitation in developing countries. Furthermore, a suggestion of adjusting transport activity data using average oil price was proposed. An illustrative case study in the Philippines revealed that the most significant driver was transport activity, followed by energy intensity, and then population growth, which was both similar and contrary to all previous studies performed in developed and rapidly urbanizing countries, which pointed out to transport activity as the primary contributing force. For the Philippines, transport activity was an inhibiting force, whereas energy intensity was the primary contributing factor. The difference could be explained by the differences in mode shares and quality of life between countries. Looking at private vehicle ownership data, it is observed that growth rates are higher in the rural, than in the urban centers. Deriving from the findings, developing a comprehensive public transport plan is recommend for future growth areas, expansion and modernization of public transport services in the city, and strategic deployment of transport policies. 相似文献
995.
While many European countries experienced a global housing boom in the early/mid-2000s, house prices and mortgage debt in Germany stagnated. Therefore, the German housing system is considered to be operating outside financialized capitalism. Despite Germany’s apparent stability, we argue that an alternative trajectory of financialization in the German housing market can be observed. This trajectory has followed three stages or ‘waves’. The first wave started around the time of German unification and is characterized by the failed attempt of West German banks to marketize and liberalize German housing finance. The second wave started in the late 1990s and is characterized by the ‘financialized privatization’ of many public housing associations and the speculative investments of private equity firms and hedge funds. The third wave started during the global financial crisis and is characterized by booming housing prices and the market entry of listed real estate companies. 相似文献
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Ilex paraguariensis crude extract acts on protection and reversion from damage induced by t‐butyl hydroperoxide in human erythrocytes: a comparative study with isolated caffeic and/or chlorogenic acids 下载免费PDF全文
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Physicochemical Changes of Connective Tissue Proteins in Jumbo Squid (Dosidicus gigas) Muscle During Ice Storage 下载免费PDF全文