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Due to the constituted ingredients are both rich in reserves, seawater sea-sand self-compacting concrete (SWSS-SCC) today has been treated as an ideal material in constructing island and coastal structures. The technique feasibility of applying SWSS-SCC in real engineering has been recognized by investigating the material properties, but its environmental impacts (EIs) has rarely been concerned at current stage. Under such a background, a refined life cycle assessment model of SWSS-SCC was developed in this study based on the China's latest production data. Life cycle phases considered include extracting and preparing raw materials, component material production, mixing concrete and transportation occurred in the whole processes. After verifying the model, the impacts of several factors like concrete curing method, fly ash incorporation content, sea-sand transportation distance and electricity generation approach, which have never been investigated before, on the energy cost and carbon dioxide equivalent emissions generated in manufacturing SWSS-SCC were discussed. The simulated results showed that: (a) Using seawater and sea-sand slightly increases the concrete's compressive and tensile strengths. Replacing some cement with fly ash notably decreases the early-age strengths, but curing at 60°C can offset that effect. (b) Replacing fresh water and natural sand by sea-water and sand in Humen Town decreases the production EIs of SWSS-SCC. For this concrete, cement production and raw material transportation are the main contributors to the overall EIs. (c) During producing SWSS-SCC, using electricity generated from clean fuels can effectively reduce the system's EI, but changing fuel used to fire the cement kiln has little effect. (d) High temperature curing to increase the fly ash content is not environmentally sound. Reducing the mixture's water to binder ratio is more benefit for incorporating fly ash. (e) From an environmental evaluation view, applying SWSS-SCC is more ecological in island constructions than coastal buildings. [ABSTRACT FROM AUTHOR]

ABSTRACT: Based on a depth-averaged 2D numerical river model, the flow and sediment movement downstream of the Cuijiaying dam Hanjiang River(China) are investigated. A new technique is employed to achieve synchronous dynamic visualization of topography and velocity field. The calculating results can reflect the relationship between flow and corresponding topography. [Copyright &y& Elsevier]

Objective: To investigate the effect of Toxoplasma gondii infection in female mice on dopamine level in the brain of male offspring., Methods: Thirty-six ICR female mice were randomly divided into control group and infection group, 18 mice in each group. Each mouse in infection group was orally infected with 10 cysts of T. gondii Prugniaud strain. On the 90th day after infection, the infected female mice were mated with normal male ICR mice at 1:1 ratio. On the 20th day of pregnancy, 2 mice in each group were delivered for fetal mice by cesarean section, and the brain of male fetal mice (n = 6) in each group were collected. On the 14th and 63rd day after birth, 6 male offspring mice in each group were sacrificed, and the brain were collected. Dopamine levels in the cortex, cerebellum, hippocampus, and striatum were analyzed by high-performance liquid chromatography-electrochemical detection (HPLC-ECD)., Results: Three mice in infection group died during the experiment, and 6 out of 15 female mice mated successfully. The number of fetal mice and F1 generation mice in infection group was 12 (male: 7) and 21 (male: 15), respectively. All the mice in control group mated successfully. The number of fetal mice and F1 generation mice was 23 (male: 12) and 179 (male: 92), respectively. The dopamine level in the cerebellum of fetal mice of infection group and control group was (413.25 ± 21.78) ng/g and (346.30 ± 51.83) ng/g, respectively (P < 0.01). No significant difference was found in dopamine content in the cortex between the two groups (P > 0.05). Compared with the control group, on the 14th day and 63rd day after birth, the dopamine content in cortical areas [(462.50 ± 24.80) ng/g and (1215.77 ± 113.64) ng/g], cerebellum area [(271.55 ± 26.19) ng/g and (1328.82 ± 39.62) ng/g], hippocampus area [(225.78 ± 24.17) ng/g and (1322.70 ± 58.34) ng/g], and striatum area [(455.23 ± 61.53) ng/g and (991.32 ± 54.31) ng/g] of the male offspring in infection group were significantly higher than that of the control (P < 0.05, P < 0.01)., Conclusion: T. gondii infection in female mice causes an increase of dopamine level in the brain of F1 generation male mice.

Objective: To observe the effect of artificially construction of the life cycle of Angiostrongylus cantonensis in the laboratory condition, so as to provide the basis for the research of angiostrongyliasis., Methods: SD rats were infected orally with the third-stage larvae of A. cantonensis collected from infected Pomacea canaliculata. Six weeks after the infection, the first-stage larvae were isolated and counted from fresh feces of the rats and then were used to infect P. canaliculata. Three weeks later, the snails were dissected for counting the third-staged larvae of A. cantonensis., Results: The first-stage larvae were detected in the feces of the rats 6 weeks after the infection, and the third-staged larvae were successfully isolated after the infection of P. canaliculata., Conclusion: The animal model of the entire life cycle of A. cantonensis is successfully established in the laboratory with the infection of 50 larvae per rat.

The recombinant transfer vector pFastBacl-ChIFN-y was constructed by plasmid pcDNA-ChIFN-gamma digested with EcoR I and Not I enzymes and cloned into pFastbacl. Then the transfer vector was transformed into E. coli competent cells DH10Bac which contained the bacmid with amini-attTn7 target site and the helper plasmid. The recombinant bacmid-ChIFN-gamma was generated by transposing themini-Tn7 element located in pFastBacl-ChIFN-gamma to themini-attTn7 attachment site on the Bacmid. Subsequently the recombinant Bacmid-ChIFN-gamma was transfected into the Sf9 insect cells mediated by lipofectin to produce recombinant baculovirus and express recombinant ChIFN-gamma (rChIFN-gamma) products. The result showed that the rChIFN-gamma was successfully expressed in Sf9 cells infected with the recombinant virus by indirect immunofluorescence assay (IFA) at 5 days post-transfection. The biological activity of rChIFN-gamma was identified by its inhibition to Vesicular stomatitis virus-induced cytotoxicity of chicken embryonic fibroblasts (CEF) in vitro. The results showed that the most efficient expression of rChIFN-gamma could be obtained at 96h post-infection with multiplicity of infection (MOI) equal to 1. It is interesting that the viruses such as Avian influenza virus H5N1 or Marek's disease virus (GA strain) could not grow in CEF pre-treated with rChIFN-gamma. Cell pathogenic efficient (CPE) in the CEF infected with H5N1 and GA strain is apparently inhibited by the rChIFN-gamma. However only difference between the HA titres of the supernatant of the pre-treated cells is observed without any obvious inhibition effect in CEF infected with Newcastle disease virus (F48E8 strain).