Linux内核提供了灵活的内核配置项机制,便于针对不同的应用场景进行个性化定制.但内核配置项的数量巨大且增长快速,配置项的默认值在不同内核版本中经常改变,即使专业的内核团队设置配置项也面临很多挑战.针对上述问题,提出基于多标签...Linux内核提供了灵活的内核配置项机制,便于针对不同的应用场景进行个性化定制.但内核配置项的数量巨大且增长快速,配置项的默认值在不同内核版本中经常改变,即使专业的内核团队设置配置项也面临很多挑战.针对上述问题,提出基于多标签的内核配置图,该图包含内核配置项间的依赖关系、功能标签、性能标签、安全标签和配置项使能率.此外,该图提供了可视化功能,更加直观、高效、人性化.该内核配置图在内核配置项异常值检测、内核启动优化、内核裁剪、内核安全增强、内核性能优化、内核配置项智能问答等场景均可应用.且将内核配置图应用到检索场景,实现了面向内核配置项的检索框架KCIR(kernel config information retrieval),该框架基于内核配置图对查询语句和内核配置项描述文本进行了扩展,实验评估表明KCIR和传统检索框架相比,检索效果有显著提升,验证了内核配置图在实际应用中的有效性和实用性.展开更多
Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural proper...Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.展开更多
The La-Mg-Ni-based A2B7-type Lao.8_xNdx Mgo.2Ni3.35Alo.lSio.o5 （x = 0, 0.1, 0.2, 0.3, and 0.4） electrode alloys were prepared by casting and annealing. The influence of the partial substitution of Nd for La on the s...The La-Mg-Ni-based A2B7-type Lao.8_xNdx Mgo.2Ni3.35Alo.lSio.o5 （x = 0, 0.1, 0.2, 0.3, and 0.4） electrode alloys were prepared by casting and annealing. The influence of the partial substitution of Nd for La on the structure and electrochemical performances of the alloys was investigated. The structural analysis of X-ray diffraction and scanning electron microscopy reveals that the experimental alloys consist of two major phases： （La,Mg）2Ni7 with the hexagonal Ce2Ni7-type structure and LaNi5 with the hexagonal CaCus-type structure as well as some residual phases of LaNi3 and NdNis. The electrochemical measurements indicate that an evident change of the electrochemical performance of the alloys is associated with the substitution of Nd for La. The discharge capacity of the alloy first increases then decreases with the growing Nd content, whereas their cycle stability clearly grows all the time. Furthermore, the measurements of the high rate discharge ability, the limiting current density, and hydrogen diffusion coefficient all demonstrate that the electrochemical kinetic properties of the alloy electrodes first augment then decline with the rising amount of Nd substitution.展开更多
The outbreak of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a serious global health threat.This raises an urgent need for the development of effective drug...The outbreak of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a serious global health threat.This raises an urgent need for the development of effective drugs against the deadly disease.SARS-CoV-2 non-structural protein 14(NSP14)carrying RNA cap guanine N7-methyltransferase and 30-50 exoribonuclease activities could be a potential drug target for intervention.NSP14 of SARS-CoV-2 shares 98.7%of similarity with the one(PDB 5NFY)of acute respiratory syndrome(SARS)by ClustalW.Then,the SARS-CoV-2 NSP14 structures were modelled by Modeller 9.18 using SARS NSP14(PDB 5NFY)as template for virtual screening.Based on the docking score from AutoDock Vina1.1.2,18 small molecule drugs were selected for further evaluation.Based on the 5 ns MD simulation trajectory,binding free energy(DG)was calculated by MM/GBSA method.The calculated binding free energies of Saquinavir,Hypericin,Baicalein and Bromocriptine for the N-terminus of the homology model wereà37.2711±3.2160,à30.1746±3.1914,à23.8953±4.4800,andà34.1350±4.3683 kcal/mol,respectively,while the calculated binding free energies wereà60.2757±4.7708,à30.9955±2.9975,à46.3099±3.5689,andà59.8104±3.5389 kcal/mol,respectively,when binding to the C-terminus.Thus,the compounds including Saquinavir,Hypericin,Baicalein and Bromocriptine could bind to the N-terminus and C-terminus of the homology model of the SARS-CoV-2 NSP14,providing a candidate drug against SARS-CoV-2 for further study.展开更多
Honokiol(HK)usage is greatly restricted by its poor aqueous solubility and limited oral bioavailability.We synthesized and characterized a novel phosphate prodrug of honokiol(HKP)for in vitro and in vivo use.HKP great...Honokiol(HK)usage is greatly restricted by its poor aqueous solubility and limited oral bioavailability.We synthesized and characterized a novel phosphate prodrug of honokiol(HKP)for in vitro and in vivo use.HKP greatly enhanced the aqueous solubility of HK(127.54±15.53 mg/ml)and the stability in buffer solution was sufficient for intravenous administration.The enzymatic hydrolysis of HKP to HK was extremely rapid in vitro(T 1/2=8.9±2.11 s).Pharmacokinetics studies demonstrated that after intravenous administration of HKP(32 mg/kg),HKP was converted rapidly to HK with a time to reach the maximum plasma concentration of^5 min.The prodrug HKP achieved an improved T 1/2(7.97±1.30 h)and terminal volume of distribution(26.02±6.04 ml/kg)compared with direct injection of the equimolar parent drug(0.66±0.01 h)and(2.90±0.342 ml/kg),respectively.Furthermore,oral administration of HKP showed rapid and improved absorption compared with the parent drug.HKP was confirmed to maintain the bioactivity of the parent drug for ameliorating ischemia-reperfusion injury by decreasing brain infarction and improving neurologic function.Taken together,HKP is a potentially useful aqueous-soluble prodrug with improved pharmacokinetic properties which may merit further development as a potential drug candidate.展开更多
文摘Linux内核提供了灵活的内核配置项机制,便于针对不同的应用场景进行个性化定制.但内核配置项的数量巨大且增长快速,配置项的默认值在不同内核版本中经常改变,即使专业的内核团队设置配置项也面临很多挑战.针对上述问题,提出基于多标签的内核配置图,该图包含内核配置项间的依赖关系、功能标签、性能标签、安全标签和配置项使能率.此外,该图提供了可视化功能,更加直观、高效、人性化.该内核配置图在内核配置项异常值检测、内核启动优化、内核裁剪、内核安全增强、内核性能优化、内核配置项智能问答等场景均可应用.且将内核配置图应用到检索场景,实现了面向内核配置项的检索框架KCIR(kernel config information retrieval),该框架基于内核配置图对查询语句和内核配置项描述文本进行了扩展,实验评估表明KCIR和传统检索框架相比,检索效果有显著提升,验证了内核配置图在实际应用中的有效性和实用性.
基金Project(2017QNA21)supported by the Fundamental Research Funds for the Central Universities of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.
基金supported by the National Natural Science Foundation of China(Nos.51161015 and 50961009)the National High Technology Research and Development Program of China(No.2011AA03A408)the Natural Science Foundation of Inner Mongolia(Nos.2011ZD10 and 2010ZD05)
文摘The La-Mg-Ni-based A2B7-type Lao.8_xNdx Mgo.2Ni3.35Alo.lSio.o5 （x = 0, 0.1, 0.2, 0.3, and 0.4） electrode alloys were prepared by casting and annealing. The influence of the partial substitution of Nd for La on the structure and electrochemical performances of the alloys was investigated. The structural analysis of X-ray diffraction and scanning electron microscopy reveals that the experimental alloys consist of two major phases： （La,Mg）2Ni7 with the hexagonal Ce2Ni7-type structure and LaNi5 with the hexagonal CaCus-type structure as well as some residual phases of LaNi3 and NdNis. The electrochemical measurements indicate that an evident change of the electrochemical performance of the alloys is associated with the substitution of Nd for La. The discharge capacity of the alloy first increases then decreases with the growing Nd content, whereas their cycle stability clearly grows all the time. Furthermore, the measurements of the high rate discharge ability, the limiting current density, and hydrogen diffusion coefficient all demonstrate that the electrochemical kinetic properties of the alloy electrodes first augment then decline with the rising amount of Nd substitution.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.31870135,31600116)the“1000 Talent Plan”of Sichuan Province(No.980)。
文摘The outbreak of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a serious global health threat.This raises an urgent need for the development of effective drugs against the deadly disease.SARS-CoV-2 non-structural protein 14(NSP14)carrying RNA cap guanine N7-methyltransferase and 30-50 exoribonuclease activities could be a potential drug target for intervention.NSP14 of SARS-CoV-2 shares 98.7%of similarity with the one(PDB 5NFY)of acute respiratory syndrome(SARS)by ClustalW.Then,the SARS-CoV-2 NSP14 structures were modelled by Modeller 9.18 using SARS NSP14(PDB 5NFY)as template for virtual screening.Based on the docking score from AutoDock Vina1.1.2,18 small molecule drugs were selected for further evaluation.Based on the 5 ns MD simulation trajectory,binding free energy(DG)was calculated by MM/GBSA method.The calculated binding free energies of Saquinavir,Hypericin,Baicalein and Bromocriptine for the N-terminus of the homology model wereà37.2711±3.2160,à30.1746±3.1914,à23.8953±4.4800,andà34.1350±4.3683 kcal/mol,respectively,while the calculated binding free energies wereà60.2757±4.7708,à30.9955±2.9975,à46.3099±3.5689,andà59.8104±3.5389 kcal/mol,respectively,when binding to the C-terminus.Thus,the compounds including Saquinavir,Hypericin,Baicalein and Bromocriptine could bind to the N-terminus and C-terminus of the homology model of the SARS-CoV-2 NSP14,providing a candidate drug against SARS-CoV-2 for further study.
基金supported by the Scientific Research Fund of the National Natural Science Foundation of China ( 81201668 )Chengdu Science and Technology Bureau ( 2015HM01-00506-SF , 2018-YF05-00454-SN )+1 种基金Scientific Research Fund of the Sichuan Provincial Education Department (17CZ0011, 17ZA0109)the Scientific Research Fund of Chengdu Medical College (CYCG15-01)
文摘Honokiol(HK)usage is greatly restricted by its poor aqueous solubility and limited oral bioavailability.We synthesized and characterized a novel phosphate prodrug of honokiol(HKP)for in vitro and in vivo use.HKP greatly enhanced the aqueous solubility of HK(127.54±15.53 mg/ml)and the stability in buffer solution was sufficient for intravenous administration.The enzymatic hydrolysis of HKP to HK was extremely rapid in vitro(T 1/2=8.9±2.11 s).Pharmacokinetics studies demonstrated that after intravenous administration of HKP(32 mg/kg),HKP was converted rapidly to HK with a time to reach the maximum plasma concentration of^5 min.The prodrug HKP achieved an improved T 1/2(7.97±1.30 h)and terminal volume of distribution(26.02±6.04 ml/kg)compared with direct injection of the equimolar parent drug(0.66±0.01 h)and(2.90±0.342 ml/kg),respectively.Furthermore,oral administration of HKP showed rapid and improved absorption compared with the parent drug.HKP was confirmed to maintain the bioactivity of the parent drug for ameliorating ischemia-reperfusion injury by decreasing brain infarction and improving neurologic function.Taken together,HKP is a potentially useful aqueous-soluble prodrug with improved pharmacokinetic properties which may merit further development as a potential drug candidate.
