BACKGROUND The long-term stability of hepatitis B surface antigen(HBsAg)seroclearance following peginterferon alpha(peg-IFN-α)-based therapy has not been extensively studied,leaving the full potential and limitations...BACKGROUND The long-term stability of hepatitis B surface antigen(HBsAg)seroclearance following peginterferon alpha(peg-IFN-α)-based therapy has not been extensively studied,leaving the full potential and limitations of this strategy unclear.AIM To assess HBsAg recurrence after seroclearance achieved by peg-IFN-αregimens.METHODS This prospective,multicenter,observational study was conducted from November 2015 to June 2021 at three Chinese hospitals:The Second Affiliated Hospital of Xi’an Jiaotong University,Ankang Central Hospital,and The Affiliated Hospital of Yan’an University.Participants who achieved HBsAg seroclearance following peg-IFN-α-based treatments were monitored every 4-12 weeks post-treatment for hepatitis B virus(HBV)markers,HBV DNA,and liver function.The primary outcome was HBV recurrence,defined as the reemergence of HBsAg,HBV DNA,or both,at least twice within 4-8 weeks of follow-up.RESULTS In total,121 patients who achieved HBsAg seroclearance were enrolled.After a median follow-up of 84.0(48.0,132.0)weeks,four subjects were lost to follow-up.HBsAg recurrence was detected in 16 patients.The cumulative HBsAg recurrence rate in the intention-to-treat population was 15.2%.Multivariate logistic regression analysis demonstrated that consolidation time<12 weeks[odds ratio(OR)=28.044,95%CI:4.525-173.791]and hepatitis B surface antibody disappearance during follow-up(OR=46.445,95%CI:2.571-838.957)were strong predictors of HBsAg recurrence.HBV DNA positivity and decompensation of liver cirrhosis and hepatocellular carcinoma were not observed.CONCLUSION HBsAg seroclearance following peg-IFN-αtreatment was durable over 84 weeks of follow-up with a cumulative recurrence rate of 15.2%.展开更多
To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is proposed.Firstly,th...To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is proposed.Firstly,the relative motion equations between multiple missiles and targets are established,and the topological model among multiple agents is considered.Secondly,based on the temporal consistency constraint,a cooperative guidance law for simultaneous arrival with finite-time convergence is derived.Finally,the unknown target maneuver-ing is regarded as bounded interference.Based on the second-order sliding mode theory,a super-twisting sliding mode observer is devised to observe and track the bounded interfer-ence,and the stability of the observer is proved.Compared with the existing research,this approach only needs to obtain the sliding mode variable which simplifies the design process.The simulation results show that the designed cooperative guidance law for maneuvering targets achieves the expected effect.It ensures successful cooperative attacks,even when confronted with strong maneuvering targets.展开更多
Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to faults.However,the effectiveness o...Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to faults.However,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection sensitivity.The present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 mm.The results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 mm.Specifically,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source.展开更多
In order to explore the effects of farmland quality evaluation on site selection of land consolidation projects,the methods of agricultural land use classification were used. Taking several project areas in Yanjin Cou...In order to explore the effects of farmland quality evaluation on site selection of land consolidation projects,the methods of agricultural land use classification were used. Taking several project areas in Yanjin County of Henan Province as examples,the farmland quality before and after land consolidation projects was evaluated. The results indicate that under the conditions of reasonable site selection,the implementation of land consolidation projects can effectively improve the farmland quality and increase the grain productivity. Therefore,before the site selection for land consolidation projects,it is recommended to carry out pre-evaluation of farmland quality,and guide the project implementation according to the evaluation results. Besides,it is recommended to focus on medium and low level farmland with large centralized area,excellent original production conditions,but low level of development and use.展开更多
DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstr...DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstream molecular biology research. In this study, three different spectrophotometry methods, BPM, NDTT and NPMTTZ were compared for their performance in determining DNA concentration and purity in 32 oil samples, and molecule methods like quantitative real-time PCR (qPCR) and high-throughput sequence were also performed to help assess the accuracy of the three methods in determining DNA concentration and purity. For ordinary heavy oil (OHO), extra heavy oil (EHO) and super heavy oil (SHO), the characteristics of high viscosity (η), density (ρ) and resin plus asphaltene content will affect the DNA extraction and UV determination. The DNA concentration was decreased as density increased: OHO (11.46 ± 18.34 ng/μL), EHO (6.68 ± 9.67 ng/μL) and SHO (6.20 ± 7.83 ng/μL), and the DNA purity was on the reverse: OHO (1.31 ± 0.27), EHO (1.54 ± 0.20), and SHO (1.83 ± 0.32). The results suggest that spectrophotometry such as BPM and NPMTTZ are qualitatively favorite methods as the quick non-consumable methods in determining DNA concentration and purity of medium oil and heavy oil.展开更多
At the Taxus base of Pengshui Miao and Tujia Autonomous County,Chongqing,the comprehensive development and utilization of Taxus was carried out with seedling cultivation,understory economy,product processing,ecotouris...At the Taxus base of Pengshui Miao and Tujia Autonomous County,Chongqing,the comprehensive development and utilization of Taxus was carried out with seedling cultivation,understory economy,product processing,ecotourism and other aspects as the main line.The benefit linkage mechanism of the operation of the Taxus industrial chain was explored and analyzed,so as to extend and supplement the Taxus industrial chain.The two models of"company+farmer"and"company+village collective+farmer"are relatively close benefit linkage models,which indirectly promote the increase of farmers income and smoothly guarantee the operation of the industrial chain,thereby playing a positive role during the development of the Taxus industry.This study provides reliable countermeasures and suggestions for the sustained and healthy development of the Taxus industry in Pengshui County.展开更多
基金Supported by National Key Research and Development Program of China,No.2023YFC2308105.
文摘BACKGROUND The long-term stability of hepatitis B surface antigen(HBsAg)seroclearance following peginterferon alpha(peg-IFN-α)-based therapy has not been extensively studied,leaving the full potential and limitations of this strategy unclear.AIM To assess HBsAg recurrence after seroclearance achieved by peg-IFN-αregimens.METHODS This prospective,multicenter,observational study was conducted from November 2015 to June 2021 at three Chinese hospitals:The Second Affiliated Hospital of Xi’an Jiaotong University,Ankang Central Hospital,and The Affiliated Hospital of Yan’an University.Participants who achieved HBsAg seroclearance following peg-IFN-α-based treatments were monitored every 4-12 weeks post-treatment for hepatitis B virus(HBV)markers,HBV DNA,and liver function.The primary outcome was HBV recurrence,defined as the reemergence of HBsAg,HBV DNA,or both,at least twice within 4-8 weeks of follow-up.RESULTS In total,121 patients who achieved HBsAg seroclearance were enrolled.After a median follow-up of 84.0(48.0,132.0)weeks,four subjects were lost to follow-up.HBsAg recurrence was detected in 16 patients.The cumulative HBsAg recurrence rate in the intention-to-treat population was 15.2%.Multivariate logistic regression analysis demonstrated that consolidation time<12 weeks[odds ratio(OR)=28.044,95%CI:4.525-173.791]and hepatitis B surface antibody disappearance during follow-up(OR=46.445,95%CI:2.571-838.957)were strong predictors of HBsAg recurrence.HBV DNA positivity and decompensation of liver cirrhosis and hepatocellular carcinoma were not observed.CONCLUSION HBsAg seroclearance following peg-IFN-αtreatment was durable over 84 weeks of follow-up with a cumulative recurrence rate of 15.2%.
基金supported by the Funds for the Central Universities。
文摘To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is proposed.Firstly,the relative motion equations between multiple missiles and targets are established,and the topological model among multiple agents is considered.Secondly,based on the temporal consistency constraint,a cooperative guidance law for simultaneous arrival with finite-time convergence is derived.Finally,the unknown target maneuver-ing is regarded as bounded interference.Based on the second-order sliding mode theory,a super-twisting sliding mode observer is devised to observe and track the bounded interfer-ence,and the stability of the observer is proved.Compared with the existing research,this approach only needs to obtain the sliding mode variable which simplifies the design process.The simulation results show that the designed cooperative guidance law for maneuvering targets achieves the expected effect.It ensures successful cooperative attacks,even when confronted with strong maneuvering targets.
文摘Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to faults.However,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection sensitivity.The present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 mm.The results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 mm.Specifically,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source.
基金Supported by Research on Theory and Techniques for Calculating Comprehensive Land Price in Land Requisition Areas
文摘In order to explore the effects of farmland quality evaluation on site selection of land consolidation projects,the methods of agricultural land use classification were used. Taking several project areas in Yanjin County of Henan Province as examples,the farmland quality before and after land consolidation projects was evaluated. The results indicate that under the conditions of reasonable site selection,the implementation of land consolidation projects can effectively improve the farmland quality and increase the grain productivity. Therefore,before the site selection for land consolidation projects,it is recommended to carry out pre-evaluation of farmland quality,and guide the project implementation according to the evaluation results. Besides,it is recommended to focus on medium and low level farmland with large centralized area,excellent original production conditions,but low level of development and use.
基金supported by grants from the PetroChina-CUP Major Strategic Cooperation Projects(ZLZX2020010805,ZLZX2020020405)National Natural Science Foundation of China(41373086)+3 种基金National Science and Technology Major Project(No.2016ZX05050011,2016ZX05040002)Beijing Nova Program and Leading Talent Culturing Cooperative Projects(No.Z161100004916033)Beijing Higher Education Young Elite Teacher Project(No.YETP0670)Outstanding Young Excellent Teachers Foundation of China University of Petroleum(Beijing)(KYJJ2012-01-10).
文摘DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstream molecular biology research. In this study, three different spectrophotometry methods, BPM, NDTT and NPMTTZ were compared for their performance in determining DNA concentration and purity in 32 oil samples, and molecule methods like quantitative real-time PCR (qPCR) and high-throughput sequence were also performed to help assess the accuracy of the three methods in determining DNA concentration and purity. For ordinary heavy oil (OHO), extra heavy oil (EHO) and super heavy oil (SHO), the characteristics of high viscosity (η), density (ρ) and resin plus asphaltene content will affect the DNA extraction and UV determination. The DNA concentration was decreased as density increased: OHO (11.46 ± 18.34 ng/μL), EHO (6.68 ± 9.67 ng/μL) and SHO (6.20 ± 7.83 ng/μL), and the DNA purity was on the reverse: OHO (1.31 ± 0.27), EHO (1.54 ± 0.20), and SHO (1.83 ± 0.32). The results suggest that spectrophotometry such as BPM and NPMTTZ are qualitatively favorite methods as the quick non-consumable methods in determining DNA concentration and purity of medium oil and heavy oil.
基金Supported by Special Key Project for Technological Innovation and Application Development in Chongqing City (cstc2021jscx-tpyzxX0017).
文摘At the Taxus base of Pengshui Miao and Tujia Autonomous County,Chongqing,the comprehensive development and utilization of Taxus was carried out with seedling cultivation,understory economy,product processing,ecotourism and other aspects as the main line.The benefit linkage mechanism of the operation of the Taxus industrial chain was explored and analyzed,so as to extend and supplement the Taxus industrial chain.The two models of"company+farmer"and"company+village collective+farmer"are relatively close benefit linkage models,which indirectly promote the increase of farmers income and smoothly guarantee the operation of the industrial chain,thereby playing a positive role during the development of the Taxus industry.This study provides reliable countermeasures and suggestions for the sustained and healthy development of the Taxus industry in Pengshui County.
