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991.
992.
A carbon footprint (CF) assessment of Chinese high‐speed railways (HSRs) can help guide further development of the world's longest HSR network. In this research, a hybrid economic input‐output and life cycle assessment (EIO‐LCA) method was applied to estimate the CF of the Beijing‐Shanghai HSR line. Specific CFs were analyzed of different subsystems of the line, different stages of production, and three calculation scopes. Results showed that the annual CF of the Beijing‐Shanghai HSR is increasing, whereas the per‐passenger CF constantly declined between 2011 and 2014. Scope 1 emissions account for an average of 4% of the total annual CF, Scope 2 contribute 71%, and Scope 3 comprise 25%. Among the different stages, operation contributes the largest (71%), followed by construction (20%) and maintenance (9%). In the construction stage, the bridges have the largest CF, followed by trains, and then rails. A trade‐off exists between the increase in carbon emissions due to construction of bridges and the reduction in operation emissions affected by leveling changes in terrain. The Beijing‐Shanghai HSR line has a relatively higher per‐passenger CF than eight other HSR lines, which is largely due to China's coal‐based carbon‐intensive energy mix of electricity generation, high proportion of bridges, higher operating speed, and heavier train body. In the future, cleaner electricity supply options, more efficient raw material production, and improvement of trains are keys to reducing the CF of Chinese HSRs.  相似文献   
993.
Three sulfonamide derivatives (SAD) were first synthesized from p‐hydroxybenzoic acid and sulfonamides (sulfadimidine, sulfamethoxazole and sulfachloropyridazine sodium) and were characterized by elemental analysis, 1H NMR and MS. The interaction between bovine serum albumin (BSA) and SAD was studied using UV/vis absorption spectroscopy, fluorescence spectroscopy, time‐resolved fluorescence spectroscopy and circular dichroism spectra under imitated physiological conditions. The experimental results indicated that SAD effectively quenched the intrinsic fluorescence of BSA via a static quenching process. The thermodynamic parameters showed that hydrogen bonding and van der Waal's forces were the predominant intermolecular forces between BSA and two SADs [4‐((4‐(N‐(4,6‐dimethylpyrimidin‐2‐yl)sulfamoyl)phenyl)carbamoyl)phenyl acetate and 4‐((4‐(N‐(5‐methylisoxazol‐3‐yl)sulfamoyl)phenyl)carbamoyl)phenyl acetate], but hydrophobic forces played a major role in the binding process of BSA and 4‐((4‐(N‐(6‐chloropyridazin‐3‐yl)sulfamoyl)phenyl) carbamoyl)phenyl acetate. In addition, the effect of SAD on the conformation of BSA was investigated using synchronous fluorescence spectroscopy and circular dichroism spectra. Molecular modeling results showed that SAD was situated in subdomain IIA of BSA. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
994.
995.
In 1941, a single type of hemocyte was described in the blood of the brine shrimp Artemia salina using light microscopy. This condition is unusual because most crustaceans examined using morphological, cytochemical, and functional methods have at least two types of hemoctyes. Upon examining A. franciscana, we found a single type of disk-shaped hemocyte, with a centrally located nucleus and about 15 large (6 microm diameter) granules. The granules stain for the presence of acid phosphatase and react with L-DOPA suggesting, respectively, that they are involved in degrading ingested material and possess the phenoloxidase system. Hemocytes require calcium for adhesion, bind together to mend small wounds in the body wall, and are able to phagocytose bacteria. Blood cells of A. franciscana are morphologically and functionally similar to those of the primitive chelicerate, Limulus polyphemus, and both forms have apparently given rise to more advanced taxa with multiple types of hemocytes. The major difference between the two species is the presence of the phenoloxidase system in the Crustacea and its apparent absence in the chelicerates.  相似文献   
996.
We used inter-simple sequence repeat fingerprinting to analyze the genetic structure of 16 populations of Stentor coeruleus from three lakes and three ponds in China. Using 14 polymorphic primers, a total of 99 discernible DNA fragments were detected, among which 76 (76.77%) were polymorphic, indicating median genetic diversity in these populations. Further, both Nei's gene diversity (h) and Shannon's information index (I) between the different populations revealed a median genetic diversity. At the same time, gene flow was interpreted to be low. The main factors responsible for the median level of diversity and low gene flow within populations are probably due to a low frequency of sexual recombinations. Analysis of molecular variance showed that there was high genetic differentiation among the five water bodies. Both cluster analysis and a nonmetric multidimensional scaling analysis suggested that genotypes isolated from the same locations displayed a higher genetic similarity than those from different ones, separating populations into subgroups according to their geographical locations. However, there is a weak positive correlation between the genetic distance and geographical distance.  相似文献   
997.
本研究以野生高含量灯盏花的叶片为外植体,在7个不同浓度NAA和BA组合的MS培养基上进行愈伤组织诱导、不定芽分化和增殖及生根的培养,确定了灯盏花快繁体系的最适培养条件:(1)初代培养基:(MS+6-BA) 0.5 mg.L-1+NAA0.1 mg.L-1;(2)丛生芽增殖培养基:(MS+6-BA) 2 mg.L-1+NAA 0.7 mg.L-1;(3) 生根培养基:(2/3MS+NAA) 0.5 mg.L-1+IBA0.8。  相似文献   
998.
Yang  Pengshuo  Yu  Shaojun  Cheng  Lin  Ning  Kang 《BMC genomics》2019,20(2):143-151
Background

The explosive growth of microbiome data provides ample opportunities to gain a better understanding of the microbes and their interactions in microbial communities. Given these massive data, optimized data mining methods become important and necessary to perform deep and comprehensive analysis. Among the various priorities for microbiome data mining, the examination of species-species co-occurrence patterns becomes one of the key themes in urgent need.

Results

Hence, in this work, we propose the Meta-Network framework to lucubrate the microbial communities. Rooted in loose definitions of network (two species co-exist in a certain samples rather than all samples) as well as association rule mining (mining more complex forms of correlations like indirect correlation and mutual information), this framework outperforms other methods in restoring the microbial communities, based on two cohorts of microbial communities: (a) the loose definition strategy is capable to generate more reasonable relationships among species in the species-species co-occurrence network; (b) important species-species co-occurrence patterns could not be identified by other existing approaches, but could successfully generated by association rule mining.

Conclusions

Results have shown that the species-species co-occurrence network we generated are much more informative than those based on traditional methods. Meta-Network has consistently constructed more meaningful networks with biologically important clusters, hubs, and provides a general approach towards deciphering the species-species co-occurrence networks.

  相似文献   
999.
Agglutinating activity often varies both between and within the algal species assayed. However, it is difficulty to interpret such variation without further analysis. We report a statistical analysis of agglutinating activities against human, cow, sheep, and pig erythrocytes, using cell extracts from 43 taxa (strains) of freshwater microalgae. Most of the extracts agglutinated erythrocytes from at least one of the sources, but pig erythrocytes appeared to be most suitable for the detection of agglutination reactions. Chlorella cell extracts preferentially agglutinated human erythrocytes, whereas extracts of other taxa were less active against mammalian erythrocytes. Cluster analysis generated four distinct subclusters of taxa, characterized by different specificities for antigens or carbohydrate receptors on the erythrocytes. Principal component analysis further separated the agglutination characteristics of Chlamydomonas from Chlorella on the first two components. Specificity for pig erythrocytes accounted for most of the clustering or grouping of algal taxa in multivariate analysis. However, clustering or grouping patterns of Chlorella species on haemagglutinating activity resembled that based on DNA sequences, revealing a possible genetic connection of agglutinins and their biochemical characteristics in algal cells. Variability of agglutination reactions among the algae investigated is simplified and interpreted most easily using multivariate analysis.  相似文献   
1000.
Li  Zhong  Azeem  Saadia  Zhang  Zhixing  Li  Zhou  Zhao  Hong  Lin  Wenxiong 《Journal of Plant Growth Regulation》2016,35(3):838-850

The study was conducted at the grain-filling stage to elucidate the physiological and molecular mechanisms of the root to enhance yield under alternate wetting and drying (AWD) compared with conventional irrigation. Measurements of root dry weight (RDW), seed setting rate, total kernel weight, and grain yield were determined along with 2D electrophoresis to detect altered protein expression in response to moderate soil drying (MD) and the subsequent recovery phase as moderate wetting (MW) under AWD compared with continuous wetting under CI. We found significant enhancement in RDW as well as 14.30 % increase in inferior spikelets, seed setting and 10.32 g m−2 increase in final yield. Among the total 55 differentially expressed proteins, 26 proteins were differentially expressed under both MD treatment and MW treatment, whereas 14 proteins under MD and 15 proteins under MW showed distinct expression. Differentially expressed proteins were involved in redox homeostasis, signaling, defense, energy, photoassimilate remobilization and included 14-3-3 proteins, cysteine-rich receptor-like protein kinase, monodehydroascorbate reductase, ascorbate peroxidase, glutathione S-transferases, translationally controlled tumor protein, remorin C-terminal domain containing protein, protein disulfide isomerase, DnaK family protein, cysteine synthase, aminotransferase, phosphoglycerate mutase, pyruvate phosphate dikinase, ATP synthase, and abscisic acid stress ripening (ASR1). The differential expression ratio of the signaling, redox, and defense group proteins was almost the same under MD and MW. ABA signaling, amino acid synthesis, and N remobilization were upregulated under MD, and the enzymes involved in carbohydrate, energy, and transportation metabolism were upregulated under MW. In conclusion, at the rice grain-filling stage, AWD is a potential technique to trigger signaling and the enzymatic protein network for systematic senescence initiation, root enlargement for maximum nutrient uptake, and maximize photoassimilate remobilization for yield enhancement.

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