Accuracy of angle-domain common-image gathers(ADCIGs)is the key to multiwave AVA inversion and migration velocity analysis,and of which Poynting vectors of pure P-and S-wave are the decisive factors in obtaining multi...Accuracy of angle-domain common-image gathers(ADCIGs)is the key to multiwave AVA inversion and migration velocity analysis,and of which Poynting vectors of pure P-and S-wave are the decisive factors in obtaining multi-component seismic data ADCIGs.A Poynting vector can be obtained from conventional velocity-stress elastic wave equations,but it focused on the propagation direction of mixed P-and S-wave fields,and neither on the propagation direction of the P-wave nor the direction of the S-wave.The Poynting vectors of pure P-or pure S-wave can be calculated from first-order velocity-dilatation-rotation equations.This study presents a method of extracting ADCIGs based on first order velocitydilatation-rotation elastic wave equations reverse-time migration algorithm.The method is as follows:calculating the pure P-wave Poynting vector of source and receiver wavefields by multiplication of P-wave particle-velocity vector and dilatation scalar,calculating the pure S-wave Poynting vector by vector multiplying S-wave particle-velocity vector and rotation vector,selecting the Poynting vector at the time of maximum P-wave energy of source wavefield as the propagation direction of incident P-wave,and obtaining the reflected P-wave(or converted S-wave)propagation direction of the receiver wavefield by the Poynting vector at the time of maximum P-(S-)wave energy in each grid point.Then,the P-wave incident angle is computed by the two propagation directions.Thus,the P-and S-wave ADGICs can obtained Numerical tests show that the proposed method can accurately compute the propagation direction and incident angle of the source and receiver wavefields,thereby achieving high-precision extraction of P-and S-wave ADGICs.展开更多
AIM:To investigate the effect of sulfated cholecystokinin-8(CCK-8S) on calcium mobilization in cultured murine gastric antral interstitial cells of Cajal(ICC) and its possible mechanisms.METHODS:ICC were isolated from...AIM:To investigate the effect of sulfated cholecystokinin-8(CCK-8S) on calcium mobilization in cultured murine gastric antral interstitial cells of Cajal(ICC) and its possible mechanisms.METHODS:ICC were isolated from the gastric antrum of mice and cultured.Immunofluorescence staining with a monoclonal antibody for c-Kit was used to identify ICC.The responsiveness of ICC to CCK-8S was measured using Fluo-3/AM based digital microfluorimetric measurement of intracellular Ca2+ concentration([Ca2+]i).A confocal laser scanning microscope was used to monitor [Ca2+]i changes.The selective CCK1 receptor antagonist lorglumide,the intracellular Ca2+-ATPase inhibitor thapsigargin,the type Ⅲ inositol 1,4,5-triphosphate(InsP3) receptor blocker xestospongin C and the L-type voltage-operated Ca2+ channel inhibitor nifedipine were used to examine the mecha-nisms of [Ca2+]i elevation caused by CCK-8S.Immunoprecipitation and Western blotting were used to determine the regulatory effect of PKC on phosphorylation of type Ⅲ InsP3 receptor(InsP3R3) in ICC.Protein kinase C(PKC) activator phorbol 12-myristate 13-acetate(PMA) and inhibitor chelerythrine were used to assess the role of PKC in the CCK-8S-evoked [Ca2+]i increment of ICC.RESULTS:ICC were successfully isolated from the gastric antrum of mice and cultured.Cultured ICC were identified by immunofluorescence staining.When given 80 nmol/L or more than 80 nmol/L CCK-8S,the [Ca2+]i in ICC increased and 100 nmol/L CCK-8S significantly increased the mean [Ca2+]i by 59.30% ± 4.85%(P < 0.01).Pretreatment of ICC with 5 μmol/L lorglumide inhibited 100 nmol/L CCK-8S-induced [Ca2+]i increment from 59.30% ± 4.85% to 14.97% ± 9.05%(P < 0.01),suggesting a CCK1R-mediated event.Emptying of intracellular calcium stores by thapsigargin(5 μmol/L) prevented CCK-8S(100 nmol/L) from inducing a [Ca2+]i increase.Moreover,pretreatment with xestospongin C(1 μmol/L) could also abolish the CCK-8S-induced effect,indicating that Ca2+ release from InsP3R-operated stores appeared to be a major mechanism responsible for CCK-8S-induced calcium mobilization in ICC.On the other hand,by removing extracellular calcium or blocking the L-type voltage-operated calcium channel with nifedipine,a smaller but significant rise in the [Ca2+]i could be still elicited by CCK-8S.These data suggest that the [Ca2+]i release is not stimulated or activated by the influx of extracellular Ca2+ in ICC,but the influx of extracellular Ca2+ can facilitate the [Ca2+]i increase evoked by CCK-8S.CCK-8S increased the phosphorylation of InsP3R3,which could be prevented by chelerythrine.Pretreatment with lorglumide(5 μmol/L) could significantly reduce the CCK-8S intensified phosphorylation of InsP3R3.In the positive control group,treatment of cells with PMA also resulted in an enhanced phosphorylation of InsP3R3.Pretreatment with various concentrations of PMA(10 nmol/L-10 μmol/L) apparently inhibited the effect of CCK-8S and the effect of100 nmol/L PMA was most obvious.Likewise,the effect of CCK-8S was augmented by the pretreatment with chelerythrine(10 nmol/L-10 μmol/L) and 100 nmol/L chelerythrine exhibited the maximum effect.CONCLUSION:CCK-8S increases [Ca2+]i in ICC via the CCK1 receptor.This effect depends on the release of InsP3R-operated Ca2+ stores,which is negatively regulated by PKC-mediated phosphorylation of InsP3R3.展开更多
Objective: To investigate the role and significance of paternally expressed gene 10 (PEG! 0) in deciduas of normal pregnant women. Methods: Sixty deciduas tissue from pregnant 6 to 11 weeks were divided into six g...Objective: To investigate the role and significance of paternally expressed gene 10 (PEG! 0) in deciduas of normal pregnant women. Methods: Sixty deciduas tissue from pregnant 6 to 11 weeks were divided into six groups and in each group ten samples were done every gestational week. The expression and distribution of PEG10 in deciduas were examined by RT-PCR, hybridization in situ, Western Blot and laser scanning confocal microscopy. Results: The PEG10 mRNA and protein were expressed in deciduas tissue from pregnant 6 to 11 weeks. Among them, the expression of PEG10 showed a gradual increase as the pregnancy weeks increased. In RT-PCR, the PEG10 expression was lower at pregnant 6th week (0.6743±0.114), from pregnant 7 to 8 weeks, the expression was increased gradually (7th week 0.7349±0.0083) and reached the pinnacle at 8th week (0.7354±0.0074). And then the pinnacle began to descend (9th week 0.6340±0.0084, 10th week 0.5901±0.0089 and llth week 0.5261±0.0112). There was a significant difference in the expression of PEG10 from pregnant 6 to 11 weeks except 7th week and 8th week. This expression characteristic was demonstrated by hybridization in situ. The similar conclusion was proved by Western Blot and laser scanning confocal microscopy. Conclusion: Expression of PEG 10 may play an important role in early pregnancy.展开更多
An inkjet-printed graphene film is of great importance for next-generation flexible, low cost and high performance electronic devices. However, due to the limitation of the inkjet printing process, the electrical cond...An inkjet-printed graphene film is of great importance for next-generation flexible, low cost and high performance electronic devices. However, due to the limitation of the inkjet printing process, the electrical conductivity of inkjet-printed graphene films is limited to N10 S'cm-1, and achieving a high conductivity of the printed graphene films remains a big challenge. Here, we develop a "weak oxidation- vigorous exfoliation" strategy to tailor graphene oxide (GO) for meeting all the requirements of highly conductive inkjet-printed graphene films, including a more intact carbon plane and suitable size. The -conjugated structure of the resulting graphene has been restored to a high degree, and its printed films show an ultrahigh conductivity of -420 S-cm-I, which is tens of times higher than previously reported results, suggesting that, aside from developing a highly efficient reduction method, tuning the GO structure could be an alternative way to produce high quality graphene sheets. Using inkjet-printed graphene patterns as source/drain/gate electrodes, and semiconducting single-walled carbon nanotubes (SWCNTs) as channels, we fabricated an all-carbon field effect transistor which shows excellent performance (an on/off ratio of -104 and a mobility of -8 cm2"V-l's-1) compared to previously reported CNT-based transistors, promising the use of nanocarbon materials, graphene and SWCNTs in printed electronics, especially where high performance and flexibility are needed.展开更多
Radiofrequency coil is one of the most important components for a nuclear magnetic resonance(NMR)instrument.In this article,some planar micro coils with an inner diameter of 2 mm and number of turns that varied from 1...Radiofrequency coil is one of the most important components for a nuclear magnetic resonance(NMR)instrument.In this article,some planar micro coils with an inner diameter of 2 mm and number of turns that varied from 1 to 11 were investigated based on the printed circuit board(PCB)technology.The electrical characterization of micro coils show that self-resonant frequencies are larger than 200 MHz.Then,an NMR measurement platform with a static magnetic field of 0.66 T was constructed and the signal to noise ratio(SNR)values of the NMR were analyzed.It was found that the SNR is optimal when the turn number of the micro coils is six and the excitation time of a 90°pulse is 0.8?s.Finally,we used the micro coil with six turns to study the transverse relaxation rate of copper sulfate pentahydrate aqueous solution with different concentrations.It was found that the transverse relaxation rate is proportional to the solution concentration.Results from the micro coil were verified by measurements using a Bruker Minispec MQ60.展开更多
Polycomb group(Pc G)proteins are crucial chromatin regulators during development.H2 AK119 ub1(H2 Aub)and H3 K27 me3 are catalyzed by Polycomb-repressive complex 1 and 2(PRC1/2)respectively,and they largely overlap in ...Polycomb group(Pc G)proteins are crucial chromatin regulators during development.H2 AK119 ub1(H2 Aub)and H3 K27 me3 are catalyzed by Polycomb-repressive complex 1 and 2(PRC1/2)respectively,and they largely overlap in the genome due to mutual recruitment of the two complexes.However,it is unclear whether PRC1/H2 Aub and PRC2/H3 K27 me3 can also function independently.By developing an ultra-sensitive carrier-DNA-assisted chromatin immunoprecipitation sequencing method termed CATCH-Seq,we generated allelic H2 Aub profiles in mouse gametes and early embryos.Our results revealed an unexpected genomewide decoupling of H2 Aub and H3 K27 me3 in mouse preimplantation embryos,where H2 Aub but not H3 K27 me3 was enriched at Pc G targets while only H3 K27 me3 was deposited in the broad distal domains associated with DNA methylation-independent non-canonical imprinting.These observations suggest that H2 Aub represses future bivalent genes during early embryogenesis without H3 K27 me3,but it is not required for the maintenance of non-canonical imprinting,which is mediated by maternal H3 K27 me3.Thus,our study reveals the distinct depositions and independent functions of H2 Aub and H3 K27 me3 during early mammalian development.展开更多
Chlorinated persistent organic pollutants, including polychlorinated biphenyls (PCBs), represent a particularly serious environmental problem and human health risk worldwide. Leguminous plants and their symbiotic ba...Chlorinated persistent organic pollutants, including polychlorinated biphenyls (PCBs), represent a particularly serious environmental problem and human health risk worldwide. Leguminous plants and their symbiotic bacteria (rhizobia) are important components of the biogeochemical cycling of nitrogen in both agricultural and natural ecosystems. However, there have been relatively few detailed studies of the remediation of PCB-contaminated soils by legume-rhizobia symbionts. Here we report for the first time evidence of the reductive dechlorination of 2,4,4'-trichlorobiphenyl (PCB 28) by an alfalfa-rhizobium nitrogen fixing symbiont. Alfalfa (Medicago sativa L.) inoculated with wild-type Sinorhizobiurn meliloti had significantly larger biomass and PCB 28 accumulation than alfalfa inoculated with the nitrogenase negative mutant rhizobium SmY. Dechlorination products of PCB 28, 2,4'-dichlorobiphenyl (PCB 8), and the emission of chloride ion (C1-) were also found to decrease significantly in the ineffective nodules infected by the mutant strain SmY. We therefore hypothesize that N2-fixation by the legume-rhizobium symbiont is coupled with the reductive dechlorination of PCBs within the nodules. The combination of these two processes is of great importance to the biogeochemical cycling and bioremediation of organochlorine pollutants in terrestrial ecosystems.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities(No.201822011)the National Key R&D Program of China(No.2018YFC1405900)+1 种基金the National Natural Science Foundation of China(Nos.41674118 and 41574105)the National Science and Technology Major Project(No.2016ZX05027002)。
文摘Accuracy of angle-domain common-image gathers(ADCIGs)is the key to multiwave AVA inversion and migration velocity analysis,and of which Poynting vectors of pure P-and S-wave are the decisive factors in obtaining multi-component seismic data ADCIGs.A Poynting vector can be obtained from conventional velocity-stress elastic wave equations,but it focused on the propagation direction of mixed P-and S-wave fields,and neither on the propagation direction of the P-wave nor the direction of the S-wave.The Poynting vectors of pure P-or pure S-wave can be calculated from first-order velocity-dilatation-rotation equations.This study presents a method of extracting ADCIGs based on first order velocitydilatation-rotation elastic wave equations reverse-time migration algorithm.The method is as follows:calculating the pure P-wave Poynting vector of source and receiver wavefields by multiplication of P-wave particle-velocity vector and dilatation scalar,calculating the pure S-wave Poynting vector by vector multiplying S-wave particle-velocity vector and rotation vector,selecting the Poynting vector at the time of maximum P-wave energy of source wavefield as the propagation direction of incident P-wave,and obtaining the reflected P-wave(or converted S-wave)propagation direction of the receiver wavefield by the Poynting vector at the time of maximum P-(S-)wave energy in each grid point.Then,the P-wave incident angle is computed by the two propagation directions.Thus,the P-and S-wave ADGICs can obtained Numerical tests show that the proposed method can accurately compute the propagation direction and incident angle of the source and receiver wavefields,thereby achieving high-precision extraction of P-and S-wave ADGICs.
基金Supported by The National Natural Science Foundation of China,No. 30900666the Programs of Department of Health of Jiangsu Province,No. H201061
文摘AIM:To investigate the effect of sulfated cholecystokinin-8(CCK-8S) on calcium mobilization in cultured murine gastric antral interstitial cells of Cajal(ICC) and its possible mechanisms.METHODS:ICC were isolated from the gastric antrum of mice and cultured.Immunofluorescence staining with a monoclonal antibody for c-Kit was used to identify ICC.The responsiveness of ICC to CCK-8S was measured using Fluo-3/AM based digital microfluorimetric measurement of intracellular Ca2+ concentration([Ca2+]i).A confocal laser scanning microscope was used to monitor [Ca2+]i changes.The selective CCK1 receptor antagonist lorglumide,the intracellular Ca2+-ATPase inhibitor thapsigargin,the type Ⅲ inositol 1,4,5-triphosphate(InsP3) receptor blocker xestospongin C and the L-type voltage-operated Ca2+ channel inhibitor nifedipine were used to examine the mecha-nisms of [Ca2+]i elevation caused by CCK-8S.Immunoprecipitation and Western blotting were used to determine the regulatory effect of PKC on phosphorylation of type Ⅲ InsP3 receptor(InsP3R3) in ICC.Protein kinase C(PKC) activator phorbol 12-myristate 13-acetate(PMA) and inhibitor chelerythrine were used to assess the role of PKC in the CCK-8S-evoked [Ca2+]i increment of ICC.RESULTS:ICC were successfully isolated from the gastric antrum of mice and cultured.Cultured ICC were identified by immunofluorescence staining.When given 80 nmol/L or more than 80 nmol/L CCK-8S,the [Ca2+]i in ICC increased and 100 nmol/L CCK-8S significantly increased the mean [Ca2+]i by 59.30% ± 4.85%(P < 0.01).Pretreatment of ICC with 5 μmol/L lorglumide inhibited 100 nmol/L CCK-8S-induced [Ca2+]i increment from 59.30% ± 4.85% to 14.97% ± 9.05%(P < 0.01),suggesting a CCK1R-mediated event.Emptying of intracellular calcium stores by thapsigargin(5 μmol/L) prevented CCK-8S(100 nmol/L) from inducing a [Ca2+]i increase.Moreover,pretreatment with xestospongin C(1 μmol/L) could also abolish the CCK-8S-induced effect,indicating that Ca2+ release from InsP3R-operated stores appeared to be a major mechanism responsible for CCK-8S-induced calcium mobilization in ICC.On the other hand,by removing extracellular calcium or blocking the L-type voltage-operated calcium channel with nifedipine,a smaller but significant rise in the [Ca2+]i could be still elicited by CCK-8S.These data suggest that the [Ca2+]i release is not stimulated or activated by the influx of extracellular Ca2+ in ICC,but the influx of extracellular Ca2+ can facilitate the [Ca2+]i increase evoked by CCK-8S.CCK-8S increased the phosphorylation of InsP3R3,which could be prevented by chelerythrine.Pretreatment with lorglumide(5 μmol/L) could significantly reduce the CCK-8S intensified phosphorylation of InsP3R3.In the positive control group,treatment of cells with PMA also resulted in an enhanced phosphorylation of InsP3R3.Pretreatment with various concentrations of PMA(10 nmol/L-10 μmol/L) apparently inhibited the effect of CCK-8S and the effect of100 nmol/L PMA was most obvious.Likewise,the effect of CCK-8S was augmented by the pretreatment with chelerythrine(10 nmol/L-10 μmol/L) and 100 nmol/L chelerythrine exhibited the maximum effect.CONCLUSION:CCK-8S increases [Ca2+]i in ICC via the CCK1 receptor.This effect depends on the release of InsP3R-operated Ca2+ stores,which is negatively regulated by PKC-mediated phosphorylation of InsP3R3.
文摘Objective: To investigate the role and significance of paternally expressed gene 10 (PEG! 0) in deciduas of normal pregnant women. Methods: Sixty deciduas tissue from pregnant 6 to 11 weeks were divided into six groups and in each group ten samples were done every gestational week. The expression and distribution of PEG10 in deciduas were examined by RT-PCR, hybridization in situ, Western Blot and laser scanning confocal microscopy. Results: The PEG10 mRNA and protein were expressed in deciduas tissue from pregnant 6 to 11 weeks. Among them, the expression of PEG10 showed a gradual increase as the pregnancy weeks increased. In RT-PCR, the PEG10 expression was lower at pregnant 6th week (0.6743±0.114), from pregnant 7 to 8 weeks, the expression was increased gradually (7th week 0.7349±0.0083) and reached the pinnacle at 8th week (0.7354±0.0074). And then the pinnacle began to descend (9th week 0.6340±0.0084, 10th week 0.5901±0.0089 and llth week 0.5261±0.0112). There was a significant difference in the expression of PEG10 from pregnant 6 to 11 weeks except 7th week and 8th week. This expression characteristic was demonstrated by hybridization in situ. The similar conclusion was proved by Western Blot and laser scanning confocal microscopy. Conclusion: Expression of PEG 10 may play an important role in early pregnancy.
文摘An inkjet-printed graphene film is of great importance for next-generation flexible, low cost and high performance electronic devices. However, due to the limitation of the inkjet printing process, the electrical conductivity of inkjet-printed graphene films is limited to N10 S'cm-1, and achieving a high conductivity of the printed graphene films remains a big challenge. Here, we develop a "weak oxidation- vigorous exfoliation" strategy to tailor graphene oxide (GO) for meeting all the requirements of highly conductive inkjet-printed graphene films, including a more intact carbon plane and suitable size. The -conjugated structure of the resulting graphene has been restored to a high degree, and its printed films show an ultrahigh conductivity of -420 S-cm-I, which is tens of times higher than previously reported results, suggesting that, aside from developing a highly efficient reduction method, tuning the GO structure could be an alternative way to produce high quality graphene sheets. Using inkjet-printed graphene patterns as source/drain/gate electrodes, and semiconducting single-walled carbon nanotubes (SWCNTs) as channels, we fabricated an all-carbon field effect transistor which shows excellent performance (an on/off ratio of -104 and a mobility of -8 cm2"V-l's-1) compared to previously reported CNT-based transistors, promising the use of nanocarbon materials, graphene and SWCNTs in printed electronics, especially where high performance and flexibility are needed.
基金supported by the National Natural Science Foundation of China(Grant No.51175083)the Jiangsu Province University Industry Cooperation Innovation Foundation-Prospective Study of China(Grant No.BY 2011135)
文摘Radiofrequency coil is one of the most important components for a nuclear magnetic resonance(NMR)instrument.In this article,some planar micro coils with an inner diameter of 2 mm and number of turns that varied from 1 to 11 were investigated based on the printed circuit board(PCB)technology.The electrical characterization of micro coils show that self-resonant frequencies are larger than 200 MHz.Then,an NMR measurement platform with a static magnetic field of 0.66 T was constructed and the signal to noise ratio(SNR)values of the NMR were analyzed.It was found that the SNR is optimal when the turn number of the micro coils is six and the excitation time of a 90°pulse is 0.8?s.Finally,we used the micro coil with six turns to study the transverse relaxation rate of copper sulfate pentahydrate aqueous solution with different concentrations.It was found that the transverse relaxation rate is proportional to the solution concentration.Results from the micro coil were verified by measurements using a Bruker Minispec MQ60.
基金supported by the National Natural Science Foundation of China(32022023 and 31871478)the National Key Research and Development Programs of China(2017YFC1001500)Zhejiang Provincial Natural Science Foundation of China(LR18C060001)。
文摘Polycomb group(Pc G)proteins are crucial chromatin regulators during development.H2 AK119 ub1(H2 Aub)and H3 K27 me3 are catalyzed by Polycomb-repressive complex 1 and 2(PRC1/2)respectively,and they largely overlap in the genome due to mutual recruitment of the two complexes.However,it is unclear whether PRC1/H2 Aub and PRC2/H3 K27 me3 can also function independently.By developing an ultra-sensitive carrier-DNA-assisted chromatin immunoprecipitation sequencing method termed CATCH-Seq,we generated allelic H2 Aub profiles in mouse gametes and early embryos.Our results revealed an unexpected genomewide decoupling of H2 Aub and H3 K27 me3 in mouse preimplantation embryos,where H2 Aub but not H3 K27 me3 was enriched at Pc G targets while only H3 K27 me3 was deposited in the broad distal domains associated with DNA methylation-independent non-canonical imprinting.These observations suggest that H2 Aub represses future bivalent genes during early embryogenesis without H3 K27 me3,but it is not required for the maintenance of non-canonical imprinting,which is mediated by maternal H3 K27 me3.Thus,our study reveals the distinct depositions and independent functions of H2 Aub and H3 K27 me3 during early mammalian development.
基金supported by the National Natural Science Foundation of China(Grant Nos.41201313&41230858)
文摘Chlorinated persistent organic pollutants, including polychlorinated biphenyls (PCBs), represent a particularly serious environmental problem and human health risk worldwide. Leguminous plants and their symbiotic bacteria (rhizobia) are important components of the biogeochemical cycling of nitrogen in both agricultural and natural ecosystems. However, there have been relatively few detailed studies of the remediation of PCB-contaminated soils by legume-rhizobia symbionts. Here we report for the first time evidence of the reductive dechlorination of 2,4,4'-trichlorobiphenyl (PCB 28) by an alfalfa-rhizobium nitrogen fixing symbiont. Alfalfa (Medicago sativa L.) inoculated with wild-type Sinorhizobiurn meliloti had significantly larger biomass and PCB 28 accumulation than alfalfa inoculated with the nitrogenase negative mutant rhizobium SmY. Dechlorination products of PCB 28, 2,4'-dichlorobiphenyl (PCB 8), and the emission of chloride ion (C1-) were also found to decrease significantly in the ineffective nodules infected by the mutant strain SmY. We therefore hypothesize that N2-fixation by the legume-rhizobium symbiont is coupled with the reductive dechlorination of PCBs within the nodules. The combination of these two processes is of great importance to the biogeochemical cycling and bioremediation of organochlorine pollutants in terrestrial ecosystems.