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Systemic vulnerability is an internal and essential factor that influences environmental sustainable development capability. Optimizing adjustments on systemic vulnerability significantly contributes to improved function, decreased disturbance, and guaranteed scientific evolution of environmental sustainable development capability. The connotation of systemic vulnerability of environmental sustainable development capability is defined and demonstrated. Measuring indexes, which reflect three aspects such as economic, ecological, and social subsystems, are established. With the application of the entropy-topsis model, statistical data from 1993 to 2012 in China are collected to carry out empirical research. The measuring values on systemic vulnerability are significantly below the standard values. On the basis of further analysis, adjustment strategy can be constituted for decreasing systemic vulnerability and improving environmentally sustainable development capability.
There is complicated correlations in mechanical system. By using the advantages of copula function to solve the related issues, this paper proposes the mechanical system reliability model based on copula function. And makes a detailed research for the serial and parallel mechanical system model and gets their reliability function respectively. Finally, the application research is carried out for serial mechanical system reliability model to prove its validity by example. Using Copula theory to make mechanical system reliability modeling and its expectation, studying the distribution of the random variables (marginal distribution) of the mechanical product’ life and associated structure of variables separately, can reduce the difficulty of multivariate probabilistic modeling and analysis to make the modeling and analysis process more clearly
Jatropha curcas L. is an excellent biofuel crop, which displays a high efficiency of carbon absorption, and seed oil of Jatropha can be efficiently processed to produce high-quality biodiesel. Plant phosphoenolpyruvate carboxylases (PEPCs) play important roles not only in initial fixation of atmospheric CO2 in C4 and Crassulacean acid metabolism (CAM) plants, but also in fatty acid biosynthesis in seeds of oil plants by regulating carbon partitioning. Here, we identified JcPEPC1 from J. curcas L. by homology cloning, and alignment analysis of protein sequence revealed JcPEPC1 was a plant C3-type PEPC, and shared high similarity to PEPC of castor oil plant Ricinus communis. We implemented detailed functional characterization of JcPEPC1 by expression analysis and transgenic tobacco. JcPEPC1 gene expressed in the leaves and seeds of J. curcas L., and remarkable increase of expression level was also detected at seed oil-accumulating stages. We overexpressed JcPEPC1 in tobacco, and showed the enzymatic activity of PEPC in transgenic plants was notably higher than wild type. Gas chromatography (GC) analysis elucidated the composition and total content of fatty acids were also altered. This study indicated JcPEPC1 played a fundamental role in fatty acid biosynthesis in Jatropha seeds. Our results proposed enhanced PEPC activity of Jatropha could improve biosynthesis of fatty acid, which implied critical functions in primary metabolism of non-photosynthetic PEPC.
In this study, two pairs of oligonucleotide primers were designed according to the nucleotide sequence of the internal transcribed spacers (ITSs) of Babesia bigemina and B. bovis isolates from China. The primers were used in a multiplex PCR to detect parasite DNA in blood samples from cattle. There was no cross reactions with B. ovata, B. major, B. sp. Kashi, Theileria annulata, T. sergenti, T. sinensis or normal bovine DNA. The sensitivity of multiplex PCR assay was 1 pg and 10 pg DNA for B. bigemina and B. bovis, respectively. A total of 260 field blood samples collected from cattle in five provinces of China were analyzed by multiplex PCR and light microscopy. PCR testing revealed that 7.3% (19/260) and 5.8% (15/260) of cattle were positive for B. bigemina and B. bovis and 1.2% (3/260) of cattle were co-infected with B. bigemina and B. bovis. Using light microscopy, 2.3% (6/260) and 1.5% (4/260) of cattle were infected by B. bigemina and B. bovis, respectively, and no co-infection was found. The results showed that the multiplex PCR developed in the present study could be an alternative diagnostic tool for the detection of B. bovis and B. bigemina infection in cattle.
In this study, we report the cloning and characteristics of an adiponectin-like receptor gene from Bombyx mori (BmAdipoR) with highly conserved deduced amino-acid sequences and similar structure to the human adiponectin receptor (AdipoR). Structural analysis of the translated cDNA suggested it encoded a membrane protein with seven transmembrane domains. BmAdipoR was found to be expressed in multiple tissues and highly expressed in Malpighian tubules, fat body and testis. BmNPV (Bombyx morinucleopolyhedrovirus) bacmid system combined with confocal microscopy revealed that BmAdipoR was targeted to the cell membrane. We also found that infection with BmNPV did not have an effect on BmAdipoR mRNA quantity in the midgut of susceptible Bombyx moristrain (306) at 48 h, but BmAdipoR mRNA quantity increased significantly at 72 h. We concluded that BmAdipoR gene was a membrane protein ubiquitously expressed in Bombyx moritissues and that its expression was altered by treating with BmNPV.
Applying the appropriate allometric equation to accurately estimate biomass is vital for the regional carbon budget. Previous studies have focused on plant biomass at a given time, and few have been conducted on biomass estimates throughout the entire lifespan of a plant. Here we used field data measured from Moso bamboo stands to validate three common allometric equations used for biomass estimates and compared their goodness of fit using Akaike’s information criterion to develop the best allometric model for Moso bamboo. Then the non-stage and staged biomass were respectively estimated using the best-fitted model, and their corresponding coefficients (or scalings) were compared to examine whether the allometric equation developed for non-stage biomass estimates were suitable for staged biomass estimates. As a result, w = aDbHc was fitted well for both total and component biomass estimates of Moso bamboo. Comparisons in allometric coefficients showed that most coefficients for staged biomass estimates exceeded the confidence interval of non-stage allometric coefficients, indicating that the staged coefficients varied as the bamboo developed. This result suggested that using a uniform allometric equation (with the same coefficients) without consideration of the variations with stage might be inadequate to accurately estimate the biomass of Moso bamboo forests throughout the entire lifespan. It can be suggested that differential allometric coefficients by stage should be applied to estimate the biomass of Moso bamboo so as to improve the accuracy of biomass estimates. These findings provide insights into the use of allometry theory for biomass estimates.
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