Monitoring the service condition of concrete structures requires the quantitative assessment of properties and corrosion rate of structural steels surrounded by concrete.A multi-cell sensor system that included a refe...Monitoring the service condition of concrete structures requires the quantitative assessment of properties and corrosion rate of structural steels surrounded by concrete.A multi-cell sensor system that included a reference electrode,a chloride content sensor,a macrocell current unit and an electrical resistance measurement unit was developed.This system provided the following important electrochemical data in the cover-zone concrete on site:open circuit potential,macrocell current from anodes to cathode,chloride profile,concrete resistance and corrosion rate of built-in anodes.The experimental results show that the macrocell current increases when the chloride content in concrete is higher.Thus,monitoring the chloride content is a good method for monitoring the corrosion state.The chloride ion content and cover depth are the key factors that affect the electrical resistance of concrete.Without considering the temperature and time,a simplified model of the instantaneous corrosion rate of steel rebar in a concrete structure based on the measured chloride contents and concrete resistance was proposed.The test results further prove the reliability of this simplified predicting model.展开更多
Subgenomic replicons of hepatitis C virus （HCV） have been widely used for studying HCV replication.Here,we report a new subgenomic replicon based on a strain isolated from a chronically infected patient.The coding s...Subgenomic replicons of hepatitis C virus （HCV） have been widely used for studying HCV replication.Here,we report a new subgenomic replicon based on a strain isolated from a chronically infected patient.The coding sequence of HCV was recovered from a Chinese chronic hepatitis C patient displaying high serum HCV copy numbers.A consensus sequence designated as CCH strain was constructed based on the sequences of five clones and this was classified by sequence alignment as belonging to genotype 2a.The subgenomic replicon of CCH was replication-deficient in cell culture,due to dysfunctions in NS3 and NS5B.Various JFH1/CCH chimeric replicons were constructed,and specific mutations were introduced.The introduction of mutations could partially restore the replication of chimeric replicons.A replication-competent chimeric construct was finally obtained by the introduction of NS3 from JFH1 into the backbone of the CCH strain.展开更多
Objectives: To evaluate thc efficacy of nested polymerasechain reaction (PCR) with first void urine (FVU) for thediagnosis of Mycoplasma hominis in male patients. Methods: Matched FVU specimens and urethral swabs were...Objectives: To evaluate thc efficacy of nested polymerasechain reaction (PCR) with first void urine (FVU) for thediagnosis of Mycoplasma hominis in male patients. Methods: Matched FVU specimens and urethral swabs werecollected from 194 male patients with NongonococcalUrethritis and tested by nested PCR and cell culture. Cellculture was used as a gold standard for evaluating other assaytechniques. Results: For FVU nested PCR assay and FVU cell culture,our results showed that the sensitivity was 100% and 93.3%;specificity was 97.0% and 98.2%; positive predictive value(PPV) was 85.7% and 90.3%, negative predictive value (NPV)was 100% and 98.8%, respectively. The total consistencybetween the two techniques was 97.4%. Conclusions: For the diagnosis of Mycoplasma hominis inmen, nested PCR detecting FVU is a highly sensitive andspecific method. First void urine can replace swab culture orPCR in terms of acceptability and feasibility.展开更多
Primordial germ cells (PGCs), as precursors of mam-malian germ lineage, have been gaining more attention as anew resource of pluripotent stem cells, which bring a greatpossibility to study developmental events of germ...Primordial germ cells (PGCs), as precursors of mam-malian germ lineage, have been gaining more attention as anew resource of pluripotent stem cells, which bring a greatpossibility to study developmental events of germ cell invitro and at animal level. EG4 cells derived from 10.5 dayspost coitum (dpc) PGCs of l29/svJ strain mouse wereestablished and maintained in an undifferentiated state.With an attempt to study the differentiation capability ofEG4 cells with a reporter protein: green fluorescence pro-tein, and the possible application of EG4 cells in the re-search of germ cell development, we have generated severalEG4-GFP cell lines expressing enhanced green fluorescenceprotein (EGFP) and still maintaining typicaI characteris-tics of pluripotent stem cells. Then, the differentiation ofEG4-GFP cells in vitro as well as their developmental fatein chimeric embryos which were produced by aggregatingEG4-GFP cells to 8-cell stage embryos were studied. Theresults showed that EG4 cells carrying green fluorescencehave a potential use in the research of germ cell develop-ment and other related studies.展开更多
Porous niobium oxide nanowires synthesized via a solvothermal method exhibited decreased bandgap,en- hanced light absorption and reduced charge-recombination rate.The porous Nb2O5 nanowires showed increased performanc...Porous niobium oxide nanowires synthesized via a solvothermal method exhibited decreased bandgap,en- hanced light absorption and reduced charge-recombination rate.The porous Nb2O5 nanowires showed increased performance for the photocatalytic H2 evolution and photo- degradation of rhodamine B,as compared to their solid counterparts,which could be ascribed to the peculiar porous nanostructure.展开更多
基金Project(200632800003-11) supported by Western Communications Construction Scientific and Technological Project in China
文摘Monitoring the service condition of concrete structures requires the quantitative assessment of properties and corrosion rate of structural steels surrounded by concrete.A multi-cell sensor system that included a reference electrode,a chloride content sensor,a macrocell current unit and an electrical resistance measurement unit was developed.This system provided the following important electrochemical data in the cover-zone concrete on site:open circuit potential,macrocell current from anodes to cathode,chloride profile,concrete resistance and corrosion rate of built-in anodes.The experimental results show that the macrocell current increases when the chloride content in concrete is higher.Thus,monitoring the chloride content is a good method for monitoring the corrosion state.The chloride ion content and cover depth are the key factors that affect the electrical resistance of concrete.Without considering the temperature and time,a simplified model of the instantaneous corrosion rate of steel rebar in a concrete structure based on the measured chloride contents and concrete resistance was proposed.The test results further prove the reliability of this simplified predicting model.
基金supported by grants from the National Basic Research Priorities Program of China(2013CB911101)the National Nature Science Foundation of China(Grant 31200315)
文摘Subgenomic replicons of hepatitis C virus （HCV） have been widely used for studying HCV replication.Here,we report a new subgenomic replicon based on a strain isolated from a chronically infected patient.The coding sequence of HCV was recovered from a Chinese chronic hepatitis C patient displaying high serum HCV copy numbers.A consensus sequence designated as CCH strain was constructed based on the sequences of five clones and this was classified by sequence alignment as belonging to genotype 2a.The subgenomic replicon of CCH was replication-deficient in cell culture,due to dysfunctions in NS3 and NS5B.Various JFH1/CCH chimeric replicons were constructed,and specific mutations were introduced.The introduction of mutations could partially restore the replication of chimeric replicons.A replication-competent chimeric construct was finally obtained by the introduction of NS3 from JFH1 into the backbone of the CCH strain.
文摘Objectives: To evaluate thc efficacy of nested polymerasechain reaction (PCR) with first void urine (FVU) for thediagnosis of Mycoplasma hominis in male patients. Methods: Matched FVU specimens and urethral swabs werecollected from 194 male patients with NongonococcalUrethritis and tested by nested PCR and cell culture. Cellculture was used as a gold standard for evaluating other assaytechniques. Results: For FVU nested PCR assay and FVU cell culture,our results showed that the sensitivity was 100% and 93.3%;specificity was 97.0% and 98.2%; positive predictive value(PPV) was 85.7% and 90.3%, negative predictive value (NPV)was 100% and 98.8%, respectively. The total consistencybetween the two techniques was 97.4%. Conclusions: For the diagnosis of Mycoplasma hominis inmen, nested PCR detecting FVU is a highly sensitive andspecific method. First void urine can replace swab culture orPCR in terms of acceptability and feasibility.
文摘Primordial germ cells (PGCs), as precursors of mam-malian germ lineage, have been gaining more attention as anew resource of pluripotent stem cells, which bring a greatpossibility to study developmental events of germ cell invitro and at animal level. EG4 cells derived from 10.5 dayspost coitum (dpc) PGCs of l29/svJ strain mouse wereestablished and maintained in an undifferentiated state.With an attempt to study the differentiation capability ofEG4 cells with a reporter protein: green fluorescence pro-tein, and the possible application of EG4 cells in the re-search of germ cell development, we have generated severalEG4-GFP cell lines expressing enhanced green fluorescenceprotein (EGFP) and still maintaining typicaI characteris-tics of pluripotent stem cells. Then, the differentiation ofEG4-GFP cells in vitro as well as their developmental fatein chimeric embryos which were produced by aggregatingEG4-GFP cells to 8-cell stage embryos were studied. Theresults showed that EG4 cells carrying green fluorescencehave a potential use in the research of germ cell develop-ment and other related studies.
基金financially supported by the National Natural Science Foundation of China (51271215 and 21601133)Sinopec Innovation Scheme (A-381)
文摘Porous niobium oxide nanowires synthesized via a solvothermal method exhibited decreased bandgap,en- hanced light absorption and reduced charge-recombination rate.The porous Nb2O5 nanowires showed increased performance for the photocatalytic H2 evolution and photo- degradation of rhodamine B,as compared to their solid counterparts,which could be ascribed to the peculiar porous nanostructure.
