We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical da...We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical data. Firstly, the thermal field in the conductive physical regime is modeled using a finite element method; based on an optimization tool, this method is applied to evaluate the location and dimensions of the deep thermal source beneath the caldera. A horizontally-extended thermal anomaly located at about 5000 m depth below sea level is identified beneath Pozzuoli Bay, a part of the CFc. The same isotherm is located at a depth of 20,000 m beyond the caldera. This indicates a higher horizontal temperature gradient in the caldera with respect to the surrounding area. Next, we utilize this thermal model to image the 3D rheological stratification of the shallow crust below the caldera with two different values of strain rates. Within the caldera, the B/D transitions with ε equal to 10^(-12) s^(-1) and 10^(-8) s^(-1) are located at 3000 m and 5000 m depths, respectively. Outside the caldera, the transition is very deep(15,000-20,000 m), seemingly uninfluenced by the thermal state of the CFc volcanism. Finally, we compare these results with the spatial distribution of earthquake hypocenters, Benioff strain release and b-value distribution to investigate the relationship between crustal rheology and seismicity characteristics. Our analysis reveals that the image of the B/D transition is in agreement with the distribution of earthquake hypocenters, constraining the potential seismogenic volume of the region. Our study demonstrates that knowledge of the rheological state of a volcanic system is an important element to interpret its dynamic, forecast future activity and improve evaluation of the associated seismic hazard.展开更多
AIM： To construct a prokaryotic expression vector carrying Campylobacterjejuni peblA gene and express it in Escherichia coli. Immunoreactivity and antigenicity of rPEB1 were evaluated. The ability of rPEB1 to induce ...AIM： To construct a prokaryotic expression vector carrying Campylobacterjejuni peblA gene and express it in Escherichia coli. Immunoreactivity and antigenicity of rPEB1 were evaluated. The ability of rPEB1 to induce antibody responses and protective efficacy was identified. METHODS： peblA gene was amplified by PCR, target gene and prokaryotic expression ptasmid pET28a （＋） was digested with BamHI and XhoI, respectively. DNA was ligated with T4 DNA ligase to construct recombinant plasmid pET28a（＋）-peblA. The rPEB1 was expressed in E. coli BL21 （DE3） and identified by SDS-PAGE. BALB/c mice were immunized with rPEBI. ELISA was used to detect the specific antibody titer and MTT method was used to measure the stimulation index of spleen lymphocyte transformation. RESULTS： The recombinant plasmid pET28a （＋）-peblA was correctly constructed. The expression output of PEB1 protein in pET28a （＋）-peblA system was approximately 33% of total proteins in E. coil The specific IgG antibody was detected in serum of BALB/c mice immunized with rPEB1 protein. Effective immunological protection with a lower sickness incidence and mortality was seen in the mice suffering from massive C. jejuni infection. CONCLUSION： rPEB1 protein is a valuable candidate for C. jejuni subunit vaccine.展开更多
基金carried out within the framework of the GEOTHERMAL ATLAS OF SOUTHERN ITALY project, one of six constituting the program CNR per il Mezzogiorno of the Italian National Research Councilpartially funded by 368 DTA. AD004.065.001 Geophysics e Project CNR _PDGP 20162018
文摘We analyze the crustal rheology beneath the active resurgent Campi Flegrei caldera(CFc) in Southern Italy by modelling the 3 D brittle-ductile(B/D) transition, based on available thermal, geological and geophysical data. Firstly, the thermal field in the conductive physical regime is modeled using a finite element method; based on an optimization tool, this method is applied to evaluate the location and dimensions of the deep thermal source beneath the caldera. A horizontally-extended thermal anomaly located at about 5000 m depth below sea level is identified beneath Pozzuoli Bay, a part of the CFc. The same isotherm is located at a depth of 20,000 m beyond the caldera. This indicates a higher horizontal temperature gradient in the caldera with respect to the surrounding area. Next, we utilize this thermal model to image the 3D rheological stratification of the shallow crust below the caldera with two different values of strain rates. Within the caldera, the B/D transitions with ε equal to 10^(-12) s^(-1) and 10^(-8) s^(-1) are located at 3000 m and 5000 m depths, respectively. Outside the caldera, the transition is very deep(15,000-20,000 m), seemingly uninfluenced by the thermal state of the CFc volcanism. Finally, we compare these results with the spatial distribution of earthquake hypocenters, Benioff strain release and b-value distribution to investigate the relationship between crustal rheology and seismicity characteristics. Our analysis reveals that the image of the B/D transition is in agreement with the distribution of earthquake hypocenters, constraining the potential seismogenic volume of the region. Our study demonstrates that knowledge of the rheological state of a volcanic system is an important element to interpret its dynamic, forecast future activity and improve evaluation of the associated seismic hazard.
基金Grants from the Governor Foundation for Excellent Talents of Guizhou Province,No.200607
文摘AIM： To construct a prokaryotic expression vector carrying Campylobacterjejuni peblA gene and express it in Escherichia coli. Immunoreactivity and antigenicity of rPEB1 were evaluated. The ability of rPEB1 to induce antibody responses and protective efficacy was identified. METHODS： peblA gene was amplified by PCR, target gene and prokaryotic expression ptasmid pET28a （＋） was digested with BamHI and XhoI, respectively. DNA was ligated with T4 DNA ligase to construct recombinant plasmid pET28a（＋）-peblA. The rPEB1 was expressed in E. coli BL21 （DE3） and identified by SDS-PAGE. BALB/c mice were immunized with rPEBI. ELISA was used to detect the specific antibody titer and MTT method was used to measure the stimulation index of spleen lymphocyte transformation. RESULTS： The recombinant plasmid pET28a （＋）-peblA was correctly constructed. The expression output of PEB1 protein in pET28a （＋）-peblA system was approximately 33% of total proteins in E. coil The specific IgG antibody was detected in serum of BALB/c mice immunized with rPEB1 protein. Effective immunological protection with a lower sickness incidence and mortality was seen in the mice suffering from massive C. jejuni infection. CONCLUSION： rPEB1 protein is a valuable candidate for C. jejuni subunit vaccine.
