Two mono iron complexes Fe（CO）2PR3（NN） （R = Cy （3）, Ph （4）, NN = o-phenylenediamine dianion ligand, N2H2Ph2-） derived from the ligand substitution of Fe（CO）3hPR3 by the NN ligand were isolated and structur...Two mono iron complexes Fe（CO）2PR3（NN） （R = Cy （3）, Ph （4）, NN = o-phenylenediamine dianion ligand, N2H2Ph2-） derived from the ligand substitution of Fe（CO）3hPR3 by the NN ligand were isolated and structurally characterized by single crystal X-ray diffraction. They have a similar first coordination sphere and oxidation state of the iron center as the [Fe]-hydrogenase active site, and can be a model of it IR demonstrated that the effect of the NN ligand on the coordinated CO stretch- ing frequencies was due to its excellent electron donating ability. The reversible protonation/deprotonation of the NN ligand was identified by infrared spectroscopy and density functional theory computation. The NN ligand is an effective proton acceptor as the internal base of the cysteine thiolate ligand in [Fe]-hydrogenase. The electrochemical properties of complexes 3, 4 were investigated by cyclic voltammograms. Complex 3 catalyzed the transfer hydrogenation of benzoquinone to hydroquinone effectively under mild conditions.展开更多
在Android系统的软件开发过程中,使用C#语言在Microsoft Visual Studio当中依靠Mono for Android插件来完成整个软件的开发。该方法能够更加简洁的开发以及调试所开发程序,并使数据绑定的过程在.net框架中予以完成。实际在开发过程中有...在Android系统的软件开发过程中,使用C#语言在Microsoft Visual Studio当中依靠Mono for Android插件来完成整个软件的开发。该方法能够更加简洁的开发以及调试所开发程序,并使数据绑定的过程在.net框架中予以完成。实际在开发过程中有操作简便,上手容易的特点。展开更多
The hardware optimization technique of mono similarity system generation is presented based on hardware/software(HW/SW) co design.First,the coarse structure of sub graphs' matching based on full customized HW...The hardware optimization technique of mono similarity system generation is presented based on hardware/software(HW/SW) co design.First,the coarse structure of sub graphs' matching based on full customized HW/SW co design is put forward.Then,a universal sub graphs' combination method is discussed.Next,a more advanced vertexes' compression algorithm based on sub graphs' combination method is discussed with great emphasis.Experiments are done successfully with perfect results verifying all the formulas and the methods above.展开更多
When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian...When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian networks. In this paper, a new monotonic constraint model is proposed to represent a type of common domain knowledge. And then, the monotonic constraint estimation algorithm is proposed to learn the parameters with the monotonic constraint model. In order to demonstrate the superiority of the proposed algorithm, series of experiments are carried out. The experiment results show that the proposed algorithm is able to obtain more accurate parameters compared to some existing algorithms while the complexity is not the highest.展开更多
Pepino mosaic virus(PepMV)causes severe disease in tomato and other Solanaceous crops around globe.To effectively study and manage this viral disease,researchers need new,sensitive,and high-throughput approaches for v...Pepino mosaic virus(PepMV)causes severe disease in tomato and other Solanaceous crops around globe.To effectively study and manage this viral disease,researchers need new,sensitive,and high-throughput approaches for viral detection.In this study,we purified PepMV particles from the infected Nicotiana benthamiana plants and used virions to immunize BALB/c mice to prepare hybridomas secreting anti-PepMV monoclonal antibodies(mAbs).A panel of highly specific and sensitive murine mAbs(15B2,8H6,23D11,20D9,3A6,and 8E3)could be produced through cell fusion,antibody selection,and cell cloning.Using the mAbs as the detection antibodies,we established double antibody sandwich enzyme-linked immunosorbent assay(DAS-ELISA),Dot-ELISA,and Tissue print-ELISA for detecting PepMV infection in tomato plants.Resulting data on sensitivity analysis assays showed that both DAS-ELISA and Dot-ELISA can efficiently monitor the virus in PepMV-infected tissue crude extracts when diluted at 1:1310720 and 1:20480(weight/volume ratio(w/v),g/mL),respectively.Among the three methods developed,the Tissue print-ELISA was found to be the most practical detection technique.Survey results from field samples by the established serological approaches were verified by reverse transcription polymerase chain reaction(RT-PCR)and DNA sequencing,dem on strati ng all three serological methods are reliable and effective for monitoring PepMV.An ti-PepMV mAbs and the newly developed DAS-ELISA,Dot-ELISA,and Tissue print-ELISA can benefit PepMV detection and field epidemiological study,and management of this viral disease,which is already widespread in tomato plants in Yunnan Province of China.展开更多
Artificial planting is an important measure to promote the restoration of degraded grassland and protect the ecological environment. The objectives of the current study were to investigate the allocation pattern betwe...Artificial planting is an important measure to promote the restoration of degraded grassland and protect the ecological environment. The objectives of the current study were to investigate the allocation pattern between aboveground biomass(AGB) and belowground biomass(BGB) in different seeding types of artificially-planted pastures. We explored the variation in biomass and the relationship between above-and belowground biomass in four artificiallyplanted pastures with one species from Elymus nutans Griseb(EN, perennial), Elymus sibiricus Linn(ES, perennial), Medicago sativa Linn(MS, perennial), and Avena sativa Linn(AS, annual) and in six artificially-planted communities with mixtures of two species by seeding ratio 1:1 from the abovementioned grasses(EN + AS, MS + AS, EN + ES, MS + EN, MS + ES, AS + ES) in 2015 and 2016. The results showed that E. nutans is the most productive species with the highest biomass production among the single crops. MS + ES was the most productive group in 2015, while the group with the highest biomass production changed to AS + ES in 2016. AGB was positively correlated to BGB in the surface soil layer in the first year, but positively related to BGB in the subsoil layer in the second year. In the early stageof artificial grassland succession, plants allocated more biomass to aboveground parts, with a root to shoot(R/S) ratio of 1.98. The slope of the log-log relationship between AGB and BGB was 1.07 in 2016, which is consistent with the isometric theory. Different sowing patterns strongly affected the accumulation and allocation of biomass in artificiallyplanted grassland, E. sibiricus was the suitable plant in the alpine regions, which will be conducive to understanding vegetation restoration and plant interactions in the future.展开更多
The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that t...The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.展开更多
Objective To evaluate whether mono（2‐ethylhexyl） phthalate（MEHP） affects genomic DNA methylation and the methylation status of some specific genes such as patched gene（PTCH） and smoothened gene（SMO） in LNCaP ...Objective To evaluate whether mono（2‐ethylhexyl） phthalate（MEHP） affects genomic DNA methylation and the methylation status of some specific genes such as patched gene（PTCH） and smoothened gene（SMO） in LNCaP cells. Methods LNCaP cells were treated with MEHP（0, 1, 5, 10, and 25 μmol/L） for 3 days. An ELISA assay was preformed to detect genomic methylation, including 5‐methylcytosine（5‐mC） and 5‐hydroxymethylcytosine（5‐hmC） content. A pyrosequencing assay was applied to assess DNA methylation in PTCH and SMO gene promoters. The correlation between DNA methylation and gene expression was assessed. Results The proportion of cytosines with 5‐mC methylation in LNCaP cells was significantly decreased by MEHP（1, 5, 10, and 25 μmol/L） in a dose‐dependent manner（P 〈 0.01）. For genes in the Hedgehog pathway, there was no significant MEHP concentration‐dependent difference in the DNA methylation of PTCH and SMO. Conclusion MEHP might affect the progression of prostate cancer through its effect on global DNA methylation.展开更多
Electronic structure calculation of bulk and monolayer MoS2 has been performed using plane wave pseudopotential method based on density functional theory. The indirect band gap in the bulk MoS2 was found to be 0.9 eV,...Electronic structure calculation of bulk and monolayer MoS2 has been performed using plane wave pseudopotential method based on density functional theory. The indirect band gap in the bulk MoS2 was found to be 0.9 eV, whereas in the monolayer-MoS2 the band gap of 1.57 eV was found to be direct one. The calculated physical parameters of monolayer MoS2 are found to be very close to the bulk MoS2 and compare well with available experimental and other theoretical results. The calculated density of states (DOS) may help explain this change in the nature of band gap in bulk and in monolayer MoS2. A further variation in band gap has been observed in MoS2 monolayer on applying biaxial strain.展开更多
Drought stress is themajor abiotic factor that can seriously affect plant growth and crop production.The functions of flavin-containing monooxygenases(FMOs)are known in animals.They addmolecular oxygen to lipophilic c...Drought stress is themajor abiotic factor that can seriously affect plant growth and crop production.The functions of flavin-containing monooxygenases(FMOs)are known in animals.They addmolecular oxygen to lipophilic compounds or produce reactive oxygen species(ROS).However,little information on FMOs in plants is available.Here,we characterized a tomato drought-responsive gene that showed homology to FMO,and it was designated as FMO1.FMO1 was downregulated promptly by drought and ABA treatments.Transgenic functional analysis indicated that RNAi suppression of the expression of FMO1(FMO1-Ri)improved drought tolerance relative to wild-type(WT)plants,whereas overexpression of FMO1(FMO1-OE)reduced drought tolerance.The FMO1-Ri plants exhibited lower ABA accumulation,higher levels of antioxidant enzyme activities,and less ROS generation comparedwith theWTand FMO1-OE plants under drought stress.RNA-seq transcriptional analysis revealed the differential expression levels of many drought-responsive genes thatwere co-expressed with FMO1,including PP2Cs,PYLs,WRKY,and LEA.Using Y2H screening,we found that FMO1 physically interacted with catalase 2(CAT2),which is an antioxidant enzyme and confers drought resistance.Our findings suggest that tomato FMO1 negatively regulates tomato drought tolerance in the ABA-dependent pathway and modulates ROS homeostasis by directly binding to SlCAT2.展开更多
Mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium(DM) was synthesized by the reaction of dysprosium isopropoxide with maleic anhydride. Dy-containing polymer(PDM) was obtained by the solution polymerization of ...Mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium(DM) was synthesized by the reaction of dysprosium isopropoxide with maleic anhydride. Dy-containing polymer(PDM) was obtained by the solution polymerization of DM using 2, 2'-azobisisobutyronitrile (AIBN) as an initiator. The kinetic study on the polymerization shows that the polymerization of DM exhibits high apparent activation energy(96.3 kJ.mol(-1)), indicating that the activity of DM is low for polymerization. The kinetic equation of polymerization can be expressed as R-P = k(P)C(DM)(1.23)c(AIBN)(0.82). The polymeric solid material shows excellent heat-stability and strong characteristic fluorescence of Dy3+, (4)Fg(9/2) --> H-6(15/2) and F-4(9/2) --> H-6(13/2).展开更多
基金supported by the National Natural Science Foundation of China(21103121,21276187)Tianjin Municipal Natural Science Foundation(13JCQNJC05800)the Specialized Research Fund for the Doctoral Program of Higher Education(20121317110009)~~
文摘Two mono iron complexes Fe（CO）2PR3（NN） （R = Cy （3）, Ph （4）, NN = o-phenylenediamine dianion ligand, N2H2Ph2-） derived from the ligand substitution of Fe（CO）3hPR3 by the NN ligand were isolated and structurally characterized by single crystal X-ray diffraction. They have a similar first coordination sphere and oxidation state of the iron center as the [Fe]-hydrogenase active site, and can be a model of it IR demonstrated that the effect of the NN ligand on the coordinated CO stretch- ing frequencies was due to its excellent electron donating ability. The reversible protonation/deprotonation of the NN ligand was identified by infrared spectroscopy and density functional theory computation. The NN ligand is an effective proton acceptor as the internal base of the cysteine thiolate ligand in [Fe]-hydrogenase. The electrochemical properties of complexes 3, 4 were investigated by cyclic voltammograms. Complex 3 catalyzed the transfer hydrogenation of benzoquinone to hydroquinone effectively under mild conditions.
文摘The hardware optimization technique of mono similarity system generation is presented based on hardware/software(HW/SW) co design.First,the coarse structure of sub graphs' matching based on full customized HW/SW co design is put forward.Then,a universal sub graphs' combination method is discussed.Next,a more advanced vertexes' compression algorithm based on sub graphs' combination method is discussed with great emphasis.Experiments are done successfully with perfect results verifying all the formulas and the methods above.
基金supported by the National Natural Science Foundation of China(6130513361573285)the Fundamental Research Funds for the Central Universities(3102016CG002)
文摘When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian networks. In this paper, a new monotonic constraint model is proposed to represent a type of common domain knowledge. And then, the monotonic constraint estimation algorithm is proposed to learn the parameters with the monotonic constraint model. In order to demonstrate the superiority of the proposed algorithm, series of experiments are carried out. The experiment results show that the proposed algorithm is able to obtain more accurate parameters compared to some existing algorithms while the complexity is not the highest.
基金National Key R&D Program of China(Nos.2019YFD1001800 and 2017YFD0201604)the National Natural Science Foundation of China(Nos.31772125 and 31972234)。
文摘Pepino mosaic virus(PepMV)causes severe disease in tomato and other Solanaceous crops around globe.To effectively study and manage this viral disease,researchers need new,sensitive,and high-throughput approaches for viral detection.In this study,we purified PepMV particles from the infected Nicotiana benthamiana plants and used virions to immunize BALB/c mice to prepare hybridomas secreting anti-PepMV monoclonal antibodies(mAbs).A panel of highly specific and sensitive murine mAbs(15B2,8H6,23D11,20D9,3A6,and 8E3)could be produced through cell fusion,antibody selection,and cell cloning.Using the mAbs as the detection antibodies,we established double antibody sandwich enzyme-linked immunosorbent assay(DAS-ELISA),Dot-ELISA,and Tissue print-ELISA for detecting PepMV infection in tomato plants.Resulting data on sensitivity analysis assays showed that both DAS-ELISA and Dot-ELISA can efficiently monitor the virus in PepMV-infected tissue crude extracts when diluted at 1:1310720 and 1:20480(weight/volume ratio(w/v),g/mL),respectively.Among the three methods developed,the Tissue print-ELISA was found to be the most practical detection technique.Survey results from field samples by the established serological approaches were verified by reverse transcription polymerase chain reaction(RT-PCR)and DNA sequencing,dem on strati ng all three serological methods are reliable and effective for monitoring PepMV.An ti-PepMV mAbs and the newly developed DAS-ELISA,Dot-ELISA,and Tissue print-ELISA can benefit PepMV detection and field epidemiological study,and management of this viral disease,which is already widespread in tomato plants in Yunnan Province of China.
基金supported by China Huaneng group technology project(Grant No.HNKJ14-H17)
文摘Artificial planting is an important measure to promote the restoration of degraded grassland and protect the ecological environment. The objectives of the current study were to investigate the allocation pattern between aboveground biomass(AGB) and belowground biomass(BGB) in different seeding types of artificially-planted pastures. We explored the variation in biomass and the relationship between above-and belowground biomass in four artificiallyplanted pastures with one species from Elymus nutans Griseb(EN, perennial), Elymus sibiricus Linn(ES, perennial), Medicago sativa Linn(MS, perennial), and Avena sativa Linn(AS, annual) and in six artificially-planted communities with mixtures of two species by seeding ratio 1:1 from the abovementioned grasses(EN + AS, MS + AS, EN + ES, MS + EN, MS + ES, AS + ES) in 2015 and 2016. The results showed that E. nutans is the most productive species with the highest biomass production among the single crops. MS + ES was the most productive group in 2015, while the group with the highest biomass production changed to AS + ES in 2016. AGB was positively correlated to BGB in the surface soil layer in the first year, but positively related to BGB in the subsoil layer in the second year. In the early stageof artificial grassland succession, plants allocated more biomass to aboveground parts, with a root to shoot(R/S) ratio of 1.98. The slope of the log-log relationship between AGB and BGB was 1.07 in 2016, which is consistent with the isometric theory. Different sowing patterns strongly affected the accumulation and allocation of biomass in artificiallyplanted grassland, E. sibiricus was the suitable plant in the alpine regions, which will be conducive to understanding vegetation restoration and plant interactions in the future.
基金supported by the National Natural Science Foundation of China(No.81273028)
文摘The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.
基金supported by the National Science and Technology Major Projects for‘Major New Drugs Innovation and Development’(No.2011ZX09301‐003)partly supported by The Fourth Round of Three‐year Public Health Action Plan of Shanghai(No.15GWZK0202)
文摘Objective To evaluate whether mono（2‐ethylhexyl） phthalate（MEHP） affects genomic DNA methylation and the methylation status of some specific genes such as patched gene（PTCH） and smoothened gene（SMO） in LNCaP cells. Methods LNCaP cells were treated with MEHP（0, 1, 5, 10, and 25 μmol/L） for 3 days. An ELISA assay was preformed to detect genomic methylation, including 5‐methylcytosine（5‐mC） and 5‐hydroxymethylcytosine（5‐hmC） content. A pyrosequencing assay was applied to assess DNA methylation in PTCH and SMO gene promoters. The correlation between DNA methylation and gene expression was assessed. Results The proportion of cytosines with 5‐mC methylation in LNCaP cells was significantly decreased by MEHP（1, 5, 10, and 25 μmol/L） in a dose‐dependent manner（P 〈 0.01）. For genes in the Hedgehog pathway, there was no significant MEHP concentration‐dependent difference in the DNA methylation of PTCH and SMO. Conclusion MEHP might affect the progression of prostate cancer through its effect on global DNA methylation.
文摘Electronic structure calculation of bulk and monolayer MoS2 has been performed using plane wave pseudopotential method based on density functional theory. The indirect band gap in the bulk MoS2 was found to be 0.9 eV, whereas in the monolayer-MoS2 the band gap of 1.57 eV was found to be direct one. The calculated physical parameters of monolayer MoS2 are found to be very close to the bulk MoS2 and compare well with available experimental and other theoretical results. The calculated density of states (DOS) may help explain this change in the nature of band gap in bulk and in monolayer MoS2. A further variation in band gap has been observed in MoS2 monolayer on applying biaxial strain.
基金supported by grants from the National Natural Science Foundation of China(No.31872123)Natural Science Foundation of Chongqing,China(No.cstc2019jcyj-msxmX0333)the Fundamental Research Funds for the Central Universities(No.XDJK2020B060).
文摘Drought stress is themajor abiotic factor that can seriously affect plant growth and crop production.The functions of flavin-containing monooxygenases(FMOs)are known in animals.They addmolecular oxygen to lipophilic compounds or produce reactive oxygen species(ROS).However,little information on FMOs in plants is available.Here,we characterized a tomato drought-responsive gene that showed homology to FMO,and it was designated as FMO1.FMO1 was downregulated promptly by drought and ABA treatments.Transgenic functional analysis indicated that RNAi suppression of the expression of FMO1(FMO1-Ri)improved drought tolerance relative to wild-type(WT)plants,whereas overexpression of FMO1(FMO1-OE)reduced drought tolerance.The FMO1-Ri plants exhibited lower ABA accumulation,higher levels of antioxidant enzyme activities,and less ROS generation comparedwith theWTand FMO1-OE plants under drought stress.RNA-seq transcriptional analysis revealed the differential expression levels of many drought-responsive genes thatwere co-expressed with FMO1,including PP2Cs,PYLs,WRKY,and LEA.Using Y2H screening,we found that FMO1 physically interacted with catalase 2(CAT2),which is an antioxidant enzyme and confers drought resistance.Our findings suggest that tomato FMO1 negatively regulates tomato drought tolerance in the ABA-dependent pathway and modulates ROS homeostasis by directly binding to SlCAT2.
文摘Mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium(DM) was synthesized by the reaction of dysprosium isopropoxide with maleic anhydride. Dy-containing polymer(PDM) was obtained by the solution polymerization of DM using 2, 2'-azobisisobutyronitrile (AIBN) as an initiator. The kinetic study on the polymerization shows that the polymerization of DM exhibits high apparent activation energy(96.3 kJ.mol(-1)), indicating that the activity of DM is low for polymerization. The kinetic equation of polymerization can be expressed as R-P = k(P)C(DM)(1.23)c(AIBN)(0.82). The polymeric solid material shows excellent heat-stability and strong characteristic fluorescence of Dy3+, (4)Fg(9/2) --> H-6(15/2) and F-4(9/2) --> H-6(13/2).
