Search

The gut–liver axis may provide a new perspective for treating anti-tuberculosis drug-induced liver injury (ATDILI). Herein, the protective effect of Lactobacillus casei (Lc) was investigated by modulating gut microflora (GM) and the toll like receptor 4 (TLR4)–nuclear factor (NF)-κB–myeloiddifferentiationfactor 88 (MyD88) pathway. C57BL/6J mice were given three levels of Lc intragastrically for 2 h before administering isoniazid and rifampicin for 8 weeks. Blood, liver, and colon tissues, as well as cecal contents, were collected for biochemical and histological examination, as well as Western blot, quantitative real time polymerase chain reaction (qRT-PCR), and 16S rRNA analyses. Lc intervention decreased alkaline phosphatase (ALP), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and tumor necrosis factor (TNF)-α levels (p < 0.05), recovered hepatic lobules, and reduced hepatocyte necrosis to alleviate liver injury induced by anti-tuberculosis drugs. Moreover, Lc also increased the abundance of Lactobacillus and Desulfovibrio and decreased Bilophila abundance, while enhancing zona occludens (ZO)-1 and claudin-1 protein expression compared with the model group (p < 0.05). Furthermore, Lc pretreatment reduced the lipopolysaccharide (LPS) level and downregulated NF-κB and MyD88 protein expression (p < 0.05), thus restraining pathway activation. Spearman correlation analysis indicated that Lactobacillus and Desulfovibrio were positively correlated with ZO-1 or occludin protein expression and negatively correlated with pathway protein expression. Desulfovibrio had significant negative relationships with alanine aminotransferase (ALT) and LPS levels. In contrast, Bilophila had negative associations with ZO-1, occludin, and claudin-1 protein expressions and positive correlations with LPS and pathway proteins. The results prove that Lactobacillus casei can enhance the intestinal barrier and change the composition of the gut microflora. Moreover, Lactobacillus casei may also inhibit TLR4–NF-κB–MyD88 pathway activation and alleviate ATDILI.

Filamentous algae are present in seawater and freshwater ecosystems worldwide. Their growth poses a serious threat to water environments and fishery production, especially Chinese mitten crab and red swamp crayfish culturing. To explore safe and ecological treatment methods, we comparatively studied the grazing effects of Xenocypris davidi Bleeker on Cladophora (one species) and Spirogyra (two species) in indoor glass tanks and examined the intestinal microbiota related to digestion and absorption. The results showed that the fish was more receptive to Spirogyra than to Cladophora, and the intake rates of different species of Spirogyra varied. Fish weight increased slightly after feeding with Spirogyra, and the levels of total nitrogen and total phosphorus in water increased significantly ( p < 0.05 ) relative to the initial values. Intestinal microbiota diversity and richness varied after feeding with three filamentous algal species, and the similarity increased after feeding with two Spirogyra species. The microbial species detected in this study belonged to 40 phyla and 838 genera. The clustering characteristics of different groups and subgroups were obvious based on the microbial phylum composition. Significant differences in the relative abundance rates of eight nutrition-related metabolism functions were found among groups and subgroups ( p < 0.05 ). The correlations between intestinal microbiota and metabolism functions were analyzed, and some meaningful correlations were revealed. The results presented in this study provided a meaningful reference on the control of the overgrowth of filamentous algae in aquaculture waters by the biomanipulation method.

A series of tests and studies were carried out on the parameters and effects of dynamic compaction (DC) for the deep and thick collapsible loess foundation under superhigh fill in the Lishi area, Shanxi Province, China. The test results indicate that a deep collapsible loess foundation can be effectively improved utilizing DC; moreover, loess collapse is significantly eliminated within the improvement range, and the effective improvement depth can be well estimated exploiting the modified Menard formula. Additionally, after the energy level of DC exceeds 2000 kN ∙ m, the characteristic value of bearing capacity of collapsible loess foundations can surpass 300 kPa, and the deformation modulus is beyond 25 MPa. The numerical model established by ABAQUS is reliable and can provide some guidance on the design and construction of similar engineering projects.

In the view of complexity theory, the emergency behavior of individual is nonlinear and influenced not only by individual variables but also by many other environmental variables. Based on complexity perspective, this article explored why employees’ taking charge behavior occurs in organizations from a multilevel approach. Specifically, this study has explored the cross-level interactive effect of organization-level factor (organizational justice climate and psychological safety climate) and individual-level factor (organizational identification) on employees’ taking charge behavior. Using a total of 806 valid matching questionnaires from 91 firms in China, this study found that first, organizational identification is positively related with employees’ taking charge behavior. Second, distributive justice climate positively moderates the influence of organizational identification on employees’ taking charge behavior. Third, psychological safety climate negatively moderates the influence of organizational identification on employees’ taking charge behavior. According to our results, organizational policies and practices should be made to foster employees’ identification with the organization, to construct a fair environment within the organization, and to convince employees that taking charge behavior will not entail political risks, especially for those employees with low organizational identification.

So far, there have been a large number of diaphragm walls in the Yangtze River Delta as engineering examples of deep foundation pit maintenance structures in subway stations, but there is a lack of systematic research and summary on the deformation characteristics of ground connecting walls. This study aimed to clarify the deformation law of the diaphragm wall during the excavation of a deep foundation pit in a soft soil region. Based on the monitoring data of the diaphragm wall of the deep foundation pit of the Hangzhou metro station, the monitoring data of the deep foundation pits of 15 subway stations in Shanghai and Ningbo cities around Hangzhou were considered. Grouping and classification methods were used to analyze the similarities and differences in the deformation characteristics of the diaphragm wall in the three regions. The results indicate the following: the maximum lateral deformation of the diaphragm wall in Hangzhou increases linearly with the relative depth of the maximum lateral deformation. The maximum lateral deformation of the foundation pit in Hangzhou is 0.072% H∼0.459% H, with a mean of 0.173% H. The wall deformation in Hangzhou varies significantly with the depth of the foundation pit, but the influence of the depth of the foundation pit on the wall deformation is considerably less than that in Shanghai and Ningbo. The corresponding position of the maximum lateral deformation in the excavation depth increases linearly with the excavation depth of the foundation pit, and the corresponding position of the lateral deformation of the diaphragm wall in Shanghai is more affected by the excavation depth of the foundation pit. The lateral deformation of the diaphragm wall increases rapidly in the range of 0 H–0.5 H, and the maximum lateral deformation occurs at 0.5 H–1.1 H.

In this paper, the complete mitochondrial DNA (mtDNA) sequence of Thryssa kammalensis was determined. The mitochondrial genome is 16,884 bp in length, including 13 protein-coding genes, 2 ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs), and a non-coding control region as those found in other vertebrates, with the gene identical to that of typical vertebrates. The overall base composition of the heavy strand is 31.07% A, 24.82% T, 28.33% C, and 15.78% G, with an AT bias of 55.89%. Phylogeny of T. kammalensis suggested more close relationship with Lycothrissa crocodilus and Setipinna taty. The complete mitogenome of this species can provide a basic data for the studies on population history, molecular systematics, phylogeography, stock evaluation, and conservation genetics.

Copper is one of the most ubiquitous environmental pollutants worldwide. Previous studies have focused on the toxicology of high copper exposure, while there has been comparatively less research on the biological effects of low copper exposure. Low concentrations of copper often exist in freshwater ecosystems, and its impact on the fish is unclear. Both Xenocypris microlepis and Xenocypris davidi are bottom-feeding fishes widely distributed in freshwater ecosystems of China, and they are more likely to be contaminated by low concentrations of copper. Low copper exposure may have effects on molecular regulation at the level of gene expression in the two Xenocypris species. To investigate gene expression differences involved in the response to low copper concentrations between X. microlepis and X. davidi, we established the responses to low copper exposure of 0.01 mg/L for 14 days at the transcriptional level, and RNA-Seq was used to perform a comparative transcriptomic analysis of the liver. A total of 74,135 and 60,894 unigenes from X. microlepis and X. davidi were assembled by transcriptome profiling, respectively. Among these, 84 genes of X. microlepis and 165 genes of X. davidi were identified as differentially expressed genes (DEGs). There were 60 and 135 up-regulated, 24 and 30 down-regulated genes in the two species, respectively. Comparative transcriptome analyses identified five differentially co-expressed genes (DCGs) related to low copper exposure from the DEGs of the two Xenocypris species. The five DCGs were related to the fishes' growth, antioxidant system, immune system and heavy metal tolerance. The results could help us to understand the molecular mechanisms of the response to low copper exposure, and the data should provide a valuable transcriptomic resource for the genus Xenocypris.

The adverse effects of anti-tuberculosis (TB) drugs in the intestines were related to alteration of the intestinal microbiota. However, there was less information about microbial metabolism on the adverse reactions. This study aimed to explore whether Lactobacillus casei could regulate gut microbiota or short-chain fatty acids (SCFAs) disorders to protect intestinal adverse reactions induced by isoniazid (H) and rifampicin (R). Male Wistar rats were given low and high doses of Lactobacillus casei two hours before daily administration of anti-TB drugs. After 42 days, colon tissue and blood were collected for analysis. The feces at two-week and six-week were collected to analyze the microbial composition and the content of SCFAs in colon contents was determined. Supplementation of Lactobacillus casei increased the proportion of intestinal goblet cells induced by H and R (p < 0.05). In addition, HR also reduced the level of mucin-2 (p < 0.05), and supplementation of Lactobacillus casei restored. After two weeks of HR intervention, a decrease in OTUs, diversity index, the abundance of Bacteroides, Akkermansia, and Blautia, and an increase of the abundance of Lacetospiraceae NK4A136 group and Rumencoccus UCG-005, were observed compared with the control group (p all < 0.05). These indices in Lactobacillus casei intervention groups were similar to the HR group. Six-week intervention resulted in a dramatic reduction of Lacetospiraceae NK4A136 group, butyric acid, valeric acid and hexanoic acid, while an increase of Bacteroides and Blautia (p all < 0.05). Pretreatment with Lactobacillus casei significantly increased the content of hexanoic acid compared with HR group (p < 0.05). Lactobacillus casei might prevent intestinal injury induced by anti-tuberculosis drugs by regulating gut microbiota and SCFAs metabolism.

As the main source of drinking water in the karst areas of southern China, underground rivers play an important supporting role in local economic and social development. However, due to the special aquifer structure in the karst areas of southern China, polycyclic aromatic hydrocarbons (PAHs) can easily enter the water environment of underground rivers and cause serious pollution, which will affect the water quality safety. In this study, Qing-shui Spring underground river in Nanning city was selected as a representative of the typical underground river in southern China, and the pollution characteristics, source analysis, ecological risk assessment and diffusion law of PAHs were studied. The results showed that the total concentration of PAHs in groundwater and surface sediments was in the range of 282.42–464.88 ng/L and 400.14–1194.69 ng/g, respectively, and the overall concentrations of PAHs were below the moderate pollution level. Pollutant discharge and physical and chemical properties of PAHs caused the concentrations of PAHs to decrease gradually from upstream to downstream, but the proportion of high-cyclic PAHs increased gradually. According to the source analysis results of the ratio method, PAHs sources in groundwater were mainly biomass combustion sources in the upstream, oil sources in the middle and mixed sources in the downstream. Sediment and groundwater had some differences. The middle and upper reaches were the source of biomass combustion, while the middle and lower reaches were the mixed source. The ecological risk assessment results showed that the ecological risk of groundwater was at a moderate level, while the ecological risk of sediment was at a low level. Benzo[a]anthracene (BaA) and benzo[b]fluoranthene (BbF) in groundwater and acenaphthylene (Acy) and fluoranthene (Flu) in sediment should be monitored intensively. Appropriate control measures should be put in place to prevent further pollution. Partition coefficients varied from 0.73 to 3.85 L/g in the sediment–water interface, increasing with the rise of PAH compounds. All of the organic carbon partition coefficients (Koc) in the sediment–water interface were higher than predicate values based on the typical model of equilibrium distribution, this indicated that PAHs were strongly adsorbed in the sediment. The linear free energy relationship coefficient between the Koc value and the n-octanol-water partition coefficient (Kow) was 0.85 but the slope was lower than 1, indicating that sediment in the Qing-shui Spring underground river had weak lipophilic characteristics and adsorption ability for PAHs. The results can provide a reference for the risk assessment and pollution control of PAHs in the karst underground rivers in South China.

Six experimental groups were established for a land-based enclosure experiment: Macrobrachium rosenbergii Monoculture group; M. rosenbergii and Hyriopsis cumingii polyculture group; M. rosenbergii and silver and bighead carp polyculture group; and M. rosenbergii, H. cumingii, and silver and bighead carp polyculture groups (GSBH1, GSBH2, and GSBH3) in different densities of H. cumingii. Each group had four replicates. Control of cyanobacterial blooms in different polyculture patterns and the effects of these patterns on water quality and microbial community were studied. Results showed that the silver and bighead carp polyculture could control cyanobacterial blooms. The H. cumingii and silver and bighead carp polyculture improved water quality, and the GSBH2 group had the best purifying effect. Moreover, different microbial communities were observed in the different polyculture patterns. The silver and bighead carp polyculture exerted obvious effect on microbial community, whereas H. cumingii only slightly affected microbial community. Water quality parameters that significantly influenced microbial community included Secchi depth transparency, total nitrogen content, total phosphorus content, total dissolved phosphate content, nitrite nitrogen content, chemical oxygen demand, and chlorophyll a content. Thus, microbial community could also serve as an indicator of nutrient levels of water bodies.

Coilia nasus is an important economic fish species in China due to its excellent meat quality and wonderful flavor. The germplasm resources of C. nasus have recently been seriously degraded by human activities. It is urgent to develop the genetic markers of C. nasus in order to apply to conservation of this species. In this study, we used C. nasus transcriptomic data from GENBANK to identify single nucleotide polymorphism (SNP) markers for this species. From 148,156 unigenes with functional annotations, 85,454 putative SNPs were identified. Forty-one of the 61 SNP loci (including 31 loci that were associated with osmoregulation-related genes and 10 loci associated with other functions) were successfully validated and showed bi-allelic polymorphism in three rivers. Nine, six and eleven of these SNP loci deviated significantly from Hardy–Weinberg equilibrium (P

Xenocypris argentea is a cyprinid fish species and widely distributed in rivers and lakes within China. The germplasm resources of X. argentea have recently been seriously degraded by human activities. Thus, the development of sufficient molecular markers to inform conservation efforts of X. argentea is urgently needed. In this study, we used Illumina HiSeq high-throughput sequencing of X. argentea transcriptomic data to identify single nucleotide polymorphism (SNP) markers for X. argentea. From 43,346 unigenes with functional annotations, 462,621 putative SNPs were identified. Among these, we validated 32 polymorphic loci of 40 function-related SNPs from a Poyang Lake population of X. argentea. Six of these SNP loci deviated significantly from Hardy–Weinberg equilibrium (P

Bighead carp (Aristichthys nobilis) is one of the most economically and ecologically important fish species widely stocked in lakes or cultured in ponds throughout China. The natural populations are facing the stringent challenges of germplasm resources reduction because of pollution and culture. Thus, developing sufficient molecular markers for the conservation and molecular-aided selection of bighead carp is urgent. In this study, we used SNaPshot to develop single nucleotide polymorphism (SNP) markers in bighead carp. A total of 38861 putative SNP markers were identified from the RAD sequencing of bighead carp. Among the markers, 28 SNPs were randomly selected and 25 loci exhibited significant polymorphisms in genotyping by SNaPshot. To the best of our knowledge, this is the first report about SNP marker development in bighead carp based on SNaPshot. These SNP markers can provide an effective tool for the resource conservation and genetic improvement of bighead carp.

Two fishing methods including gillnetting and trawling to estimate attributes of fish assemblage were compared in Dianshan Lake from August 2009 to July 2010. Species composition differed significantly between the gears, with four significant contributors in gillnet catches and one in trawl catches. Trawling collected more proportions of benthic species by number and biomass than gillnetting. Size distribution was significantly influenced by fishing technique; gillnetting captured relatively less small-sized fishes and trawling captured less large-sized individuals. Trawling produced species richness closer to the one expected than gillnetting. On the whole, trawl catch was a quadratic polynomial function of gillnet catch and a significantly negative correlation was found between them, both of which varied as different polynomial functions of temperature. However, trawl and gillnet catches were significantly correlated only in one of five month groups. It is concluded that single-gear-based surveys can be misleading in assessments of attributes of fish assemblages, bottom trawling is a more effective gear for assessing fish diversity than benthic gillnetting, and using gillnet catches as an indicator of fish density depends on fishing season in the lake.

Saturated sandy stratum often makes tunnel excavation exceedingly difficult owing to its high water content. The artificial ground-freezing (AGF) method is an effective way to reduce the construction risks in such stratum; however, the AGF mechanism in the saturated sandy stratum of a collapsible loess area still lacks sufficient research. Based on field tests and numerical simulations, this study investigates the regularity of the temperature development, frost heave, and thaw subsidence distribution during the cross passage construction of a saturated sandy stratum in a collapsible loess area, using the AGF method. The results showed that the inward development rate of the frozen soil wall in the saturated sandy stratum was faster than its outward development rate. The gradient of the soil cooling curve was positively related to the longitudinal depth of the cross passage. The thickness of the frozen soil wall calculated by the slowest development rate of the frozen soil was conservative. The application of the pressure relief hole was beneficial to the release of the frost-heaving force and the control of the frost-heaving displacement. The pressure gauge pressure increase could be used as an identifier for the closure of a frozen soil wall. After excavation, the inner wall of the cross passage moved toward the inner space of the passage.

This study investigated the complementary effect of three orientations of knowledge management (KM) strategy on firm performance: external and internal, explicit and tacit, and exploratory and exploitive. We propose a theoretical framework for examining the synergistic effects of KM strategy on firm performance, and the moderating effect of organizational structure. The complementary effect among these orientations of KM strategy was studied. To test our framework, we conducted a survey with a sample of 345 Chinese firms that had applied a KM strategy. The empirical results show that: (1) different KM strategy orientations complement each other, and this complementarity is an essential link in the relationship between KM strategy and firm performance, (2) the direct effect of each orientation of KM strategy on firm performance is not significant, (3) a centralized organizational structure moderates the relationship between KM strategy and firm performance, thus the more centralized is the organizational structure, the stronger is the positive impact of the complementary effect of KM strategy on firm performance, and (4) the moderating effect of formalized organizational structure in the relationship between KM strategy and firm performance is not significant.

This paper studied the sources of food and the trophic levels of silver and bighead carps using stable isotopes (δ 13 C and δ 15 N) analysis in Lake Qiandao and Lake Taihu. The δ 13 C values of POM and phytoplankton indicated that Particulate Organic Matter (POM) is of terrestrial origin in LQ and phytoplankton origin in LT. The different signature of δ 15 N of phytoplankton and POM also showed the different extent of anthropogenic impacts on the two lakes, with higher impacts in LT than in LQ. In LQ the trophic levels of silver and bighead carps were significantly different (2.48 ± 0.19 and 2.66 ± 0.19, respectively), while in LT the difference was not significant (2.15 ± 1.54 and 2.36 ± 0.38, respectively). Using a mixing model, we found that silver and bighead carps consumed a major proportion on phytoplankton and/or POM in both lakes with higher contribution of phytoplankton in more eutrophic lake. Silver and bighead carps had clear differentiation in food resources with silver carp more on POM and bighead more on zooplankton in deep and mesotrophic lakes. Contrary to this, both carps fed primarily on phytoplankton (and POM) and may have more niche overlaps in shallow and eutrophic lakes.

In order to explore the effect of different dam structures on the genetic diversity of freshwater fish, the genetic diversity of Sinibrama macrops in Min River was investigated using mitochondrial control region (D-loop) sequences. Populations of S. macrops at Jianyang and Shaowu rivers were separated from the rest of the system by low dams and the population at Gutian was isolated from the rest of the river by a high dam. The haplotype diversity in the samples analyzed varied from 0.577 to 0.933 and nucleotide diversity varied from 0.0031 to 0.00441. The lowest values of haplotype diversity and nucleotide diversity were obtained from Gutian. Indices of genetic differentiation between populations, gene flow, analysis of molecular variance and net genetic distance between populations showed widespread gene exchange among different populations, with the exception of Gutian and Yongtai. These results may be associated with the isolation of Gutian by the high dam. The result of neutrality test and mismatch distributions showed that the evolutionary history of Gutian population was different from others in the river system. Our results imply that high dams have a larger effect on S. macrops , leading to reduction of genetic diversity and genetic differentiation from other populations.

Understanding how the discharge-rate and the hydraulic gradient of a karst aquifer varies in response to rainfall events is important for the efficient management of water resources in these aquifers. The relationship between discharge and hydraulic gradient is related to aquifer properties such as the physical characteristics of the karstic matrix, hydraulic conductivity and the extent to which water is exchanged between conduits and the matrix. In this study, discharge and hydraulic gradient data were monitored at 4-h intervals for 476 continuous days in the Zhaidi karst aquifer located in Guilin, Guangxi Province, China. These data showed that the relationship between flow rate and hydraulic gradient in the aquifer became increasing non-linear with increasing flow rates. After analyzing the time series data, a hydrodynamic threshold between quickflow- and baseflow conditions was found to take place at a discharge rate of 0.80 m3/s. The linear law and nonlinear equations were obtained between discharge and hydraulic gradient which reflected the flow mechanism of groundwater flow in this karst aquifer.

Partial sequences of mitochondrial DNA 16S rDNA and COI genes (395 bp and 498 bp respectively) were sequenced from samples of ten cultured populations of Macrobrachium rosenbergii (Giant Freshwater Prawn – GFP) in Zhejiang, Guangdong and Guangxi Provinces in China and two wild populations of GFP from Mekong River and Dongnai River in Viet Nam. Five haplotypes of 16S rDNA were identified in the 360 samples. The wild populations displayed nucleotide diversity (π) of 0.0008 and 0.0003, and genetic diversity (h) of 0.3030 and 0.1310 in the Mekong River and Dongnai River respectively. The cultured populations displayed no significant genetic diversity. COI sequences identified 17 haplotypes based on 21 polymorphic sites. At this marker, the 12 populations showed a range of h from 0.1290 to 0.6940 and π from 0.0003 to 0.0073. The largest genetic distance (Da) among the 12 populations was 0.0065 (between ZJB and BT/DN populations) and the lowest Da was 0.0003 (between GDD and GDA populations). The wild populations had higher genetic diversity than the cultured populations, but three of cultured populations from Zhejiang (ZJA, ZJB and ZJC) had π higher than wild populations, because they originated from Thailand, Bangladesh and the Mekong River in Viet Nam.

Coilia nasus is widely distributed along the coast, and rivers and lakes that connect with the ocean in China. It is a diadromous fish but has residential populations in the middle and lower reach of the Yangtze River and its associated lakes such as Lake Taihu. These ecologically differentiated diadromous and residential populations are difficult to identify and separate, even with current molecular screening methods such as applying the mtDNA markers. The objective of the present study was to screen these populations by the means of the whole body elemental fingerprint analysis (EFA). Our results showed that the diadromous population had significantly lower concentrations of Al, B, Ca, Cr, Fe, K, Mg, Mn, P, S, and Zn, and significantly higher As than the residential populations. The spawners had lower concentrations of B, Cr, P, and S before laying eggs than after laying eggs. Advanced statistical models detected distinct spatial patterns between the diadromous and residential populations, and between groups before and after spawning. The current study showed that the whole body EFA can clearly distinguish C. nasus populations in the Yangtze River Basin and thus proved to be useful and may substitute the elemental fingerprint of fish otolith in future fish ecological studies that need to identify different populations. (C) 2015 Elsevier Ltd. All rights reserved.

The Giant freshwater prawn (GFP), Macrobrachium rosenbergii, is one of the most important crustacean species cultured in China, but information on the genetic diversity of GFP in China is still limited. In this study we analyzed the genetic diversity of 6 cultured GFP populations collected in China, and 2 wild populations from Viet Nam. The wild populations were included as a reference so that the genetic diversity of the introduced cultured GFP populations could be evaluated. We used six polymorphic primer pairs to estimate genetic diversity. Results showed that the number of alleles per locus ranged from 6 to 19. The mean observed heterozygosity (0.364 ± 0.090) was less than the expected heterozygosity (0.893 ± 0.016); highly significant deficiencies in heterozygotes were detected (100%). The polymorphism information content (PIC) of 8 populations at 6 loci was greater than 0.5 (varying from 0.616 to 0.912). Pair-wise genetic differentiation (FST) varied from 0.006 to 0.129 among the eight populations. The dendrogram based on genetic distance showed six populations distributed on the same major branch, suggesting that they have closely genetic distance and two populations (ZJC and GDB) distributed on the other branch, so they also have closely genetic distance. The results of study provide a baseline assessment of genetic diversity in some populations in China and Viet Nam that will be useful for the development of breeding programmes in the future.

A new genus and species, Sinorhodeus microlepis gen. et sp. nov., is described from a tributary of the Yangtze River, in Chongqing City, China. Sinorhodeus gen. nov. can be distinguished from four closely related genera, Paratanakia, Pseudorhodeus, Rhodeus, and Tanakia, by the following combination of characters: pharyngeal teeth 0,0,4–4,0,0, longitudinal scales 41–46, white spots on dorsal-fin rays absent, a black blotch on dorsal fin in juvenile absent, and less developed wing-like yolk sac projections in larvae. Phylogenetic analysis of one mitochondrial gene and six nuclear genes supports the establishment of the new genus.

High-throughput sequencing analysis of gut contents was used to study the feeding habits of two filter-feeding fish, namely silver carp Hypophthalmichthys molitrix and bighead carp Hypophthalmichthys nobilis, in mesotrophic Lake Qiandao and eutrophic Lake Taihu. Silver carp feed primarily on phytoplankton, with a feeding preference for Chlorophyta, in Lake Qiandao and rely on phytoplankton in Lake Taihu. Bighead carp feed more on zooplankton in Lake Qiandao and on phytoplankton in Lake Taihu. With increasing levels of algae, bighead carp feed more on phytoplankton. The dietary shifts suggest that bighead carp would be useful in controlling nuisance algae in lakes.

Through the analysis of monitoring data with a time interval of 10 min during the rainy season of 2012, for three points of G37, zk8 and zk7 which are located on the main conduit of Zhaidi karst underground river system, the variation features of water level and hydraulic gradient are studied and the relations are established between gradient and water level or amplitude. (1) It is first discovered that there are different function relations such as linear, parabola and inverse parabola between the G37’s water level and the hydraulic gradients of different conduit part. (2) The peak delay times for water level curves are

A 924 bp segment of the mitochondrial control region ( d -loop) was sequenced and analyzed in 334 specimens of Sinibrama macrops from 13 sites in Qiantang River Basin, China. Haplotype diversity ( h = 0.724 ± 0.063) and nucleotide diversity ( π = 0.00263 ± 0.00027) were lowest in Shengzhou population which had been separated from mainstream of Qiantang River Basin by seawater. The results of pairwise Fst values and average genetic distance revealed significant divergence between Shengzhou and other populations. No geographic clustering was observed in haplotype network, suggesting that there were gene flow among populations except Shengzhou. Pairwise mismatch distributions and Tajima's d -test showed demographic history of Shengzhou population was different from others. Base on the analysis of mitochondrial control region, the differentiation of Shengzhou population was considered to be the result of the transgression and regression in the last interglacial period.

This paper develops a simulation model to investigate competitive technology diffusion, and focuses on examining the influence of customer learning on the evolution of market share when both technologies exhibit local network externalities. Results show that: (1) the equilibrium market share of the new technology is determined by two key factors: the characteristics of customer learning behavior and the strength of local network externalities; (2) moderate network externalities can be beneficial for new technology to dominate the entire market when customers adopt belief-based learning rule; (3) moderate learning rate would facilitate the diffusion of new technology when customers make their decisions based on reinforcement learning; (4) the decay of customer learning and the proportions of imitators in market would help the old technology establish advantage by maintaining demand inertia of customer. The joint effects of psychology of customer behavior and local interactions of customers offer a new mechanism to explain the diffusion of technology in a competitive market with network externalities.

In order to understand the influence of human activities such as habitat fragmentation on freshwater fish population evolution, we investigated and compared the genetic diversity and phylogeography of Sinibrama macrops populations in the Oujiang River and Ling River. Mitochondrial control region sequences (D-loop region) of 131 specimens from six populations were obtained and analyzed. The diversity of main stream in the Ou River was lower than that in Ling River. Changtan population showed the lowest diversity (H = 0.646 ± 0.077; π = 0.00060 ± 0.00820). Pairwise F