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
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
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
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.
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
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.