This paper investigates mechanical behaviours of sandstone during post-peak cyclic loading and unloading subjected to hydromechanical coupling effect, confirming the peak and residual strengths reduction laws of sands...This paper investigates mechanical behaviours of sandstone during post-peak cyclic loading and unloading subjected to hydromechanical coupling effect, confirming the peak and residual strengths reduction laws of sandstone with water pressure, and revealing the influence of water pressure on the upper limit stress and deformation characteristics of sandstone during post-peak cyclic loading and unloading.Regarding the rock strength, the experimental study confirms that the peak strength σ_(p) and residual strength σ_(r) decrease as water pressure P increases. Especially, the normalized strength parameters σ_(p)/σ_(pk) and σ_(r)/σ_(re) was negatively and linearly correlated with the P/σ_(3). Moreover, the Hoek-Brown strength criterion can be applied to describe the relationship between effective peak strength and effective confining stress. During post-peak cyclic loading and unloading, both the upper limit stress σ_(p(i)) and crack damage threshold stress σ_(cd(i)) of each cycle tend to decrease with the increasing cycle number. A hysteresis loop exists among the loading and unloading stress–strain curves, indicating the unloading deformation modulus E_(unload) is larger than the loading deformation modulus E_(load). Based on experimental results,a post-peak strength prediction model related to water pressure and plastic shear strain is established.展开更多
With the introduction of various carbon reduction policies around the world,hydrogen energy,as a kind of clean energy with zero carbon emission,has attracted much attention.The safe and economical transportation of hy...With the introduction of various carbon reduction policies around the world,hydrogen energy,as a kind of clean energy with zero carbon emission,has attracted much attention.The safe and economical transportation of hydrogen is of great significance to the development of hydrogen energy industries.Utilizing natural gas pipelines to transport hydrogen is considered to be an efficient and economical way.However,hydrogen has a higher risk of leakage due to its strong diffusion capacity and lower explosive limit than conventional natural gas.Therefore,it is of great significance to study the leakage and diffusion law of hydrogen-enriched natural gas(HENG)pipelines for the safe transportation of hydrogen energy.In this study,the leakage and diffusion characteristics of urban buried HENG pipelines are investigated numerically,and the dangerous degree of leakage is analyzed based on the time and area when the gas concentration reaches the lower explosive limit.The influences of hydrogen blending ratio(HBR),operating pressure,leakage hole size and direction,as well as soil type on the leakage and diffusion law of HENG are analyzed.Results show that the hydrogen mixing is not the key factor in increasing the degree of risk after gas leakage for urban buried HENG pipelines.When the HBR is 5%,10%,15% and 20%,the corresponding first dangerous time is 1053,1041,1019 and 998 s,respectively.Thiswork is expected to provide a valuable reference for the safe operation and risk prevention of HENG pipelines in the future.展开更多
The authors regret that ‘Houquan Zhang’applies to remove his name and affiliation from the author list because he thought that he didn't make enough great contributions to this paper,just dis-cus:sion about the ...The authors regret that ‘Houquan Zhang’applies to remove his name and affiliation from the author list because he thought that he didn't make enough great contributions to this paper,just dis-cus:sion about the outline for the paper writing and some revision suggestions.The correct author list and affi liations are updated as above.展开更多
In this paper,the hydrogeological characteristics in the southern coalfields of China are first briefly outlined.Then,taking the Meitanba mine as an example,the evolution and modeling of mine water inflow are studied....In this paper,the hydrogeological characteristics in the southern coalfields of China are first briefly outlined.Then,taking the Meitanba mine as an example,the evolution and modeling of mine water inflow are studied.Finally,the hazard characteristics related to mine water and mud inrush are analyzed.The results show that the main mine water sources in the Meitanba mine area are groundwater,surface water and precipitation.The evolution of mine water inflow with time indicates that the water inflow is closely related to the development of karst structures,the amount of water from rainfall infiltration,and the scope of groundwater depression cone.The mine water inflow increases with time due to the increase in mining depth and the expansion of groundwater depression cone.Using the big well method and following the potential superposition principle,a hydrogeological model considering multi-well interactions has been developed to predict the mine water inflow.Based on the monitored data in the Meitanba mine area over a period of nearly 60 years,it is found that with increasing mining depth,the number of water and mud inrush points tended to decrease.However,the average water and mud flow rate per point tended to increase.展开更多
Objective: To analyze characterization of the rpoBgene mutations of Mycobacterium tuber- culosis isolated from China and to explore the association of specific mutations conferring rifampicin (RIF) resistance with Bei...Objective: To analyze characterization of the rpoBgene mutations of Mycobacterium tuber- culosis isolated from China and to explore the association of specific mutations conferring rifampicin (RIF) resistance with Beijing genotype strains. Methods: Genotypic analysis of 3479M. tuberculosis isolatesincluding 402 RIF-resistantand 3077 RIF-susceptible isolated from the na- tional drug-resistant tuberculosis baseline survey was performed. Results: DNA sequencing analysis of the 81-bp RIF resistance determining region (RRDR) of the ropB gene revealed that 98.01% of RIF-resistant strains showedrpoBgene mutation, isolates with mutations at codon rpoB531, rpoB 526 and rpoB 516 were the most frequently. Analysis of the rpoB gene of 3077 RIF-susceptible strains revealed that 98.96% of the strains had no mutation. The distribution of mutation frequency at differentcritical codons in different regions of China was statistically significant (p = 0.001). There was no significant difference in the occurrence of mutations at critical codons between the rifampicin-resistant Bei-jing and non-Beijing isolates.Conclusion: About 98% of RIF-resistant strains isolated from China carry mutations in RRDR ofrpoB gene.Mutation profiles in RIF-resistantM. tuberculosis clinical isolates are variable depending on the different geographical regionsof China. The results provide valuable information in adopting new molecular methods for diagnosis of TB in China.展开更多
With the rapid development of the individualized demand market,the demand for manufacturing flexibility has increased over time.As a result,a cell manufacturing system suitable for many varieties and small batches has...With the rapid development of the individualized demand market,the demand for manufacturing flexibility has increased over time.As a result,a cell manufacturing system suitable for many varieties and small batches has been produced.With the goal of minimizing the area and logistics handling volume,and considering the arrangement order of facilities and channel constraints,a mathematical model was established,and the problem was solved by improved NSGA-II.After non-dominated sorting,traditional NSGA-II will cross-operate the individuals with the best sorting to generate new individuals.Such a selection strategy is extremely easy to fall into the local optimal solution.The improved NSGA-II is to improve the original selection operation,which is to select the first half of the excellent individuals in the non-dominated sorting into the cross operation,and then select the last sorted ones of the remaining individuals into the cross operation,and combine the best and the worst ones into the cross operation.Finally,an example is given to simulate and improve the solution of NSGA-II and NSGA-II.The simulation results indicate that the improved NSGA-II population shows more obvious diversity,it is easier to jump out of the local optimal solution than NSGA-II,and the satisfactory layout scheme of manufacturing cells is obtained.Therefore,it is more effective to use improved NSGA-II to solve the problem of manufacturing cell layout.展开更多
To distinguish Mycobacterium tuberculosis from Mycobacterium avium, specific M. tuberculosis antigens had been studied for improving the early differential diagnosis effect of tuberculosis caused by different Mycobact...To distinguish Mycobacterium tuberculosis from Mycobacterium avium, specific M. tuberculosis antigens had been studied for improving the early differential diagnosis effect of tuberculosis caused by different Mycobacterium. The rabbit anti-M. avium sera and anti-M. tuberculosis sera were analyzed for antibody-based reactivity by matrix-assisted laser desorption-ionization mass spectrometry (MALDI-TOF Mass) against M. tuberculosis proteins. The immunoreactive spots, which were attributed to the proteins HspX, GroES and CFP-10, were mostly located at 10 - 60 kDa and PI 4 - 6, subsequently Western blotting result proved that HspX and CFP-10 were specific to M. tuberculosis and ELISA testing result of 30 M. avium positive sera showed that GroES were cross-reactive to M. avium. Lastly, positive and negative tuberculosis reference sera and based on the mechanism of indirect ELISA, the specificity and the sensitivity of the methods targeting the antibodies HspX, GroES or CFP-10 were evaluated at 37% and 26%, 12% and 97%, 81% and 98%, respectively. The combination of these three antibody detection methods allowed to reached a specificity of 42%, and of 39% without taken into account of the method targeting the GroES antibody. Using proteomics approach, we found three M. tuberculosis specific antigens showed good potential in tuberculosis diagnosis, providing basic study for serodiagnosis of tuberculosis.展开更多
Summary What is already known about this topic?The coronavirus disease(COVID-19)pandemic could have a damaging impact on access to tuberculosis(TB)diagnosis and treatment.What is added by this report?The overall delay...Summary What is already known about this topic?The coronavirus disease(COVID-19)pandemic could have a damaging impact on access to tuberculosis(TB)diagnosis and treatment.What is added by this report?The overall delay experienced by TB patients during the COVID-19 pandemic has shown a modest decrease in comparison to the period before the pandemic.Notably,higher patient delays were observed among agricultural workers and those identified through passive case-finding methods.Furthermore,the patient delay in eastern regions was shorter compared to western and central regions.展开更多
In this work,particle transport in a fully developed turbulent 90°bend flow at the"electrostatic equi-librium"state is simulated using large eddy simulation coupled with Lagrangian particle tracking tec...In this work,particle transport in a fully developed turbulent 90°bend flow at the"electrostatic equi-librium"state is simulated using large eddy simulation coupled with Lagrangian particle tracking technique.The flow Reynolds numbers(based on bulk velocity)considered is from 34000 to 58000.Three particle size 5,10 and 50μm are considered and their corresponding St number are from 2.2 to 547.Simulation results of the bend flow agree well with experimental data.The electrostatic field formed in the bend is symmetric in the spanwise direction but asymmetric in the vertical direction and radial direction,which is independent of Reynolds number.The minimum electrostatic field strength occurs at r/ra=0.25 near the inner wall of the bend.Particles transported in a bend gradually accumulate near the wall due to turbophoresis,such trend is improved by electrostatics.In addition,under the effect of electrostatics,the plume pattern of particle distribution disappeared.Particle concentration at the inner wall of the bend is higher than that at the outer wall,which depends on the combined effect of elec-trostatics and Dean vortices in the bend.展开更多
Particle behavior in a turbulent flow in a circular pipe with a bed height h=0.5R is studied at Reb=40,000 and for two sizes of particles(5μm and 50μm)using large eddy simulation,one-way coupled with a Lagrangian pa...Particle behavior in a turbulent flow in a circular pipe with a bed height h=0.5R is studied at Reb=40,000 and for two sizes of particles(5μm and 50μm)using large eddy simulation,one-way coupled with a Lagrangian particle tracking technique.Turbulent secondary flows are found within the pipe,with the curved upper wall affecting the secondary flow formation giving rise to a pair of large upper vortices above two smaller vortices close to the pipe floor.The behavior of the two sizes of particle is found to be quite different.The 50μm particles deposit forming irregular elongated particle streaks close to the pipe floor,particularly at the center of the flow and the pipe corners due to the impact of the secondary flows.The deposition and resuspension rate of the 5μm particles is high near the center of the floor and at the pipe corners,while values for the 50μm particles are greatest near the corners.Near the curved upper wall of the pipe,the deposition rate of the 5μm particles increases in moving from the wall center to the corners,and is greater than that for the larger particles due to the effects of the secondary flow.The maximum resuspension rate of the smaller particles occurs above the pipe corners,with the 50μm particles showing their highest resuspension rate above and at the corners of the pipe.展开更多
Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.Wha...Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.What is added by this report?This manuscript reported the national representative total and breakdown costs associated with TB care in China.The total cost per patient was 1,185 USD,of which 88%was direct cost and 37%was incurred prior to TB treatment.展开更多
Summary What is already known about this topic?Tuberculosis(TB)is a multisystem disease that might affect any organ.Currently,the National TB Program(NTP)issued by the State Council of China,only covers pulmonary tube...Summary What is already known about this topic?Tuberculosis(TB)is a multisystem disease that might affect any organ.Currently,the National TB Program(NTP)issued by the State Council of China,only covers pulmonary tuberculosis(PTB),and the status of extrapulmonary tuberculosis(EPTB)remains unclear nationwide.What is added by this report?The survey conducted by China CDC reported that there were no specific health facilities responsible for diagnosis,treatment and management of EPTB in China,while more than half of counties thought it should be included into NTP.展开更多
In solid processing systems,electrostatic problems are commonly observed for granules of various shapes.However,a complete understanding of the basic dependence of electrostatic charge generation on particle shape has...In solid processing systems,electrostatic problems are commonly observed for granules of various shapes.However,a complete understanding of the basic dependence of electrostatic charge generation on particle shape has yet to be established.This observation motivated the present study on examining the effect of granular shape on electrostatics.In this study,polyvinyl chloride(PVC) granules(diameter 1.1-4.1 mm,in the shape of a triangle or trapezium) were first discharged to remove any residual charges and subsequently their electrostatic charging characteristics were studied by allowing a granule to slide along a pipe wall.Several factors such as granular front-facing angle,length-ratio,sliding area,sliding orientation,sliding times,and relative humidity were considered when studying their effects on the electrostatic charging of granules.It was found that triangular granules with smaller front-facing angles tended to generate more electrostatic charge.The amount of electrostatic charge increased with granular lengthratio and sliding area but decreased with humidity.In addition,granular sliding in the orientation of the front-facing angle(for triangular granules) or the short side(for trapezoidal granules) generated more electrostatic charge than that in the orientation of the long side.For both granule shapes,the electrostatic charge increased with granular sliding times and reached a saturated state after around 8-9 sliding movements.The saturated electrostatic charge increased with either granular length ratio or sliding area.展开更多
Introduction:The year 2019 was crucial for the implementation of China’s National“13th 5-Year”Tuberculosis(TB)Control Plan.We conducted this study to evaluate the characteristics and progress towards controlling TB...Introduction:The year 2019 was crucial for the implementation of China’s National“13th 5-Year”Tuberculosis(TB)Control Plan.We conducted this study to evaluate the characteristics and progress towards controlling TB in China.Methods:We collected and analyzed the pulmonary tuberculosis(PTB)data of China between January 1,2015 and December 31,2019 from the National Notifiable Disease Reporting System(NNDRS).Results:In 2019,there were 775,764 PTB cases reported in NNDRS,of which 349,307 were bacteriologically-confirmed(Bac+)cases.The PTB case notification rate(CNR)was 55.55 per 100,000,and the Bac+CNR was 25.01 per 100,000.From 2018 to 2019,the number of PTB cases fell by 6.3%,but the number of Bac+cases increased by 25.9%.The annual decrease in the rate of reported PTB was 3.4% from 2015 to 2019.The 5 provincial-level administrative divisions(PLADs)with the highest PTB CNR were as follows:Tibet(182.38 per 100,000),Xinjiang(169.05 per 100,000),Qinghai(134.53 per 100,000),Guizhou(102.51 per 100,000),and Hainan(90.22 per 100,000).The rate of reported PTB was 74.84 per 100,000 for males and 35.40 per 100,000 for females.There were 8,116 cases(1.0%)among children aged 0–14 years,and 197,730 cases(25.5%)among adults aged 65 years and over.Of the reported cases,470,932 were farmers,which was the most common occupation at 60.7%.Conclusions and Implications for Public Health Practice:The TB epidemic has decreased dramatically year by year.Most PTB cases were in the central and western regions of China,and the high-risk groups were farmers and elderly people aged 65 years and over.展开更多
Introduction:National Notifiable Disease Reporting System(NNDRS)plays an important role in the early detection and control of tuberculosis(TB)in China.This study analyzed the epidemiological characteristics of pulmona...Introduction:National Notifiable Disease Reporting System(NNDRS)plays an important role in the early detection and control of tuberculosis(TB)in China.This study analyzed the epidemiological characteristics of pulmonary tuberculosis(PTB)in Kashgar Prefecture,Xinjiang Uygur Autnomous Region,China from 2011 to 2020 to provide a scientific basis for developing TB control strategies and measures in Kashgar.Methods:The data were collected from the NNDRS,which included the geographical distribution,age,sex,occupation,and pathogenic classification of reported PTB cases in 12 counties/cities of Kashgar Prefecture from 2011 to 2020.Descriptive statistics were used to describe the characteristic of PTB epidemic in Kashgar.Results:There were 189,416 PTB cases reported during 2011–2020,with a mean annual PTB case notification rate(CNR)of 451.29/100,000.A rising trend in the rate of reported PTB between 2011 and 2017(χ2 trend=26.09,P<0.01)and a declining trend between 2018 and 2020(χ2 trend=314.44,P<0.01)were observed.The months with the highest reported number of PTB cases were March to May and November to December.The mean annual rate of reported PTB was 451.88/100,000 for males and 450.67/100,000 for females.In addition,19.76%of patients were bacteriologically-confirmed(Bac+)cases(37,425/189,416),and the mean annual Bac+CNR was 89.17/100,000,rising from 64.76/100,000 in 2011 to 139.12/100,000 in 2020(χ^(2)_(trend)=74.44,P<0.01).Conclusions:The CNR of reported PTB in Kashgar showed a significant declining trend in the past three years.Males,elderly population,winter and spring,and farmers as an occupation were the main factors associated with high incidence of tuberculosis in Kashgar.Targeted prevention and treatment of TB should be strengthened in key groups in this region.展开更多
Summary What is already known about this topic?The World Health Organization has estimated the impact of reductions in the performance of global tuberculosis(TB)detection and care on TB deaths.However,the actual impac...Summary What is already known about this topic?The World Health Organization has estimated the impact of reductions in the performance of global tuberculosis(TB)detection and care on TB deaths.However,the actual impact of COVID-19 pandemic on TB deaths in China remains unclear.What is added by this report?The stringent public interventions to fight COVID-19 including lockdown led to more than 20%decrease of TB detection in China.展开更多
What is already known about this topic?Tuberculosis(TB)notification data and the underreporting rate are major sources used in estimating TB incidence.China’s TB Information Management System(TBIMS)was launched in 20...What is already known about this topic?Tuberculosis(TB)notification data and the underreporting rate are major sources used in estimating TB incidence.China’s TB Information Management System(TBIMS)was launched in 2005 but has not yet been evaluated for sensitivity.What is added by this report?The average underreporting rate of pulmonary TB to TBIMS in selected facilities was 8.23%.However,provincial TB or infectious disease-specific health facilities,or general health facilities had higher underreporting rates.Children,migrants,and drug resistant TB patients had higher chances to be underreported than other populations.What are the implications for public health practice?Underreporting surveys should be routinely implemented in the future.This will be vital for enhancing TB reporting and the transfer mechanisms in TB or infectious disease-specific hospitals,or general hospitals and improving the case information registration procedures in designated health facilities(DHFs).展开更多
基金supported by the National Natural Science Foundation of China(Nos.52274118 and 52274145)the Construction Project of Chenzhou National Sustainable Development Agenda Innovation Demonstration Zone(No.2021sfQ18).
文摘This paper investigates mechanical behaviours of sandstone during post-peak cyclic loading and unloading subjected to hydromechanical coupling effect, confirming the peak and residual strengths reduction laws of sandstone with water pressure, and revealing the influence of water pressure on the upper limit stress and deformation characteristics of sandstone during post-peak cyclic loading and unloading.Regarding the rock strength, the experimental study confirms that the peak strength σ_(p) and residual strength σ_(r) decrease as water pressure P increases. Especially, the normalized strength parameters σ_(p)/σ_(pk) and σ_(r)/σ_(re) was negatively and linearly correlated with the P/σ_(3). Moreover, the Hoek-Brown strength criterion can be applied to describe the relationship between effective peak strength and effective confining stress. During post-peak cyclic loading and unloading, both the upper limit stress σ_(p(i)) and crack damage threshold stress σ_(cd(i)) of each cycle tend to decrease with the increasing cycle number. A hysteresis loop exists among the loading and unloading stress–strain curves, indicating the unloading deformation modulus E_(unload) is larger than the loading deformation modulus E_(load). Based on experimental results,a post-peak strength prediction model related to water pressure and plastic shear strain is established.
基金supported by the National Key R&D Program of China (No.2021YFB4001602),the National Natural Science Foundation of China (No.51904031)the Award Cultivation Foundation from Beijing Institute of Petrochemical Technology (No.BIPTACF-002).
文摘With the introduction of various carbon reduction policies around the world,hydrogen energy,as a kind of clean energy with zero carbon emission,has attracted much attention.The safe and economical transportation of hydrogen is of great significance to the development of hydrogen energy industries.Utilizing natural gas pipelines to transport hydrogen is considered to be an efficient and economical way.However,hydrogen has a higher risk of leakage due to its strong diffusion capacity and lower explosive limit than conventional natural gas.Therefore,it is of great significance to study the leakage and diffusion law of hydrogen-enriched natural gas(HENG)pipelines for the safe transportation of hydrogen energy.In this study,the leakage and diffusion characteristics of urban buried HENG pipelines are investigated numerically,and the dangerous degree of leakage is analyzed based on the time and area when the gas concentration reaches the lower explosive limit.The influences of hydrogen blending ratio(HBR),operating pressure,leakage hole size and direction,as well as soil type on the leakage and diffusion law of HENG are analyzed.Results show that the hydrogen mixing is not the key factor in increasing the degree of risk after gas leakage for urban buried HENG pipelines.When the HBR is 5%,10%,15% and 20%,the corresponding first dangerous time is 1053,1041,1019 and 998 s,respectively.Thiswork is expected to provide a valuable reference for the safe operation and risk prevention of HENG pipelines in the future.
文摘The authors regret that ‘Houquan Zhang’applies to remove his name and affiliation from the author list because he thought that he didn't make enough great contributions to this paper,just dis-cus:sion about the outline for the paper writing and some revision suggestions.The correct author list and affi liations are updated as above.
基金This research is supported by the National Natural Science Foundation of China(Nos.51774131,51874133)Construction Project of Chenzhou National Sustainable Development Agenda Innovation Demonstration Zone(2021sfQ18).
文摘In this paper,the hydrogeological characteristics in the southern coalfields of China are first briefly outlined.Then,taking the Meitanba mine as an example,the evolution and modeling of mine water inflow are studied.Finally,the hazard characteristics related to mine water and mud inrush are analyzed.The results show that the main mine water sources in the Meitanba mine area are groundwater,surface water and precipitation.The evolution of mine water inflow with time indicates that the water inflow is closely related to the development of karst structures,the amount of water from rainfall infiltration,and the scope of groundwater depression cone.The mine water inflow increases with time due to the increase in mining depth and the expansion of groundwater depression cone.Using the big well method and following the potential superposition principle,a hydrogeological model considering multi-well interactions has been developed to predict the mine water inflow.Based on the monitored data in the Meitanba mine area over a period of nearly 60 years,it is found that with increasing mining depth,the number of water and mud inrush points tended to decrease.However,the average water and mud flow rate per point tended to increase.
文摘Objective: To analyze characterization of the rpoBgene mutations of Mycobacterium tuber- culosis isolated from China and to explore the association of specific mutations conferring rifampicin (RIF) resistance with Beijing genotype strains. Methods: Genotypic analysis of 3479M. tuberculosis isolatesincluding 402 RIF-resistantand 3077 RIF-susceptible isolated from the na- tional drug-resistant tuberculosis baseline survey was performed. Results: DNA sequencing analysis of the 81-bp RIF resistance determining region (RRDR) of the ropB gene revealed that 98.01% of RIF-resistant strains showedrpoBgene mutation, isolates with mutations at codon rpoB531, rpoB 526 and rpoB 516 were the most frequently. Analysis of the rpoB gene of 3077 RIF-susceptible strains revealed that 98.96% of the strains had no mutation. The distribution of mutation frequency at differentcritical codons in different regions of China was statistically significant (p = 0.001). There was no significant difference in the occurrence of mutations at critical codons between the rifampicin-resistant Bei-jing and non-Beijing isolates.Conclusion: About 98% of RIF-resistant strains isolated from China carry mutations in RRDR ofrpoB gene.Mutation profiles in RIF-resistantM. tuberculosis clinical isolates are variable depending on the different geographical regionsof China. The results provide valuable information in adopting new molecular methods for diagnosis of TB in China.
文摘With the rapid development of the individualized demand market,the demand for manufacturing flexibility has increased over time.As a result,a cell manufacturing system suitable for many varieties and small batches has been produced.With the goal of minimizing the area and logistics handling volume,and considering the arrangement order of facilities and channel constraints,a mathematical model was established,and the problem was solved by improved NSGA-II.After non-dominated sorting,traditional NSGA-II will cross-operate the individuals with the best sorting to generate new individuals.Such a selection strategy is extremely easy to fall into the local optimal solution.The improved NSGA-II is to improve the original selection operation,which is to select the first half of the excellent individuals in the non-dominated sorting into the cross operation,and then select the last sorted ones of the remaining individuals into the cross operation,and combine the best and the worst ones into the cross operation.Finally,an example is given to simulate and improve the solution of NSGA-II and NSGA-II.The simulation results indicate that the improved NSGA-II population shows more obvious diversity,it is easier to jump out of the local optimal solution than NSGA-II,and the satisfactory layout scheme of manufacturing cells is obtained.Therefore,it is more effective to use improved NSGA-II to solve the problem of manufacturing cell layout.
文摘To distinguish Mycobacterium tuberculosis from Mycobacterium avium, specific M. tuberculosis antigens had been studied for improving the early differential diagnosis effect of tuberculosis caused by different Mycobacterium. The rabbit anti-M. avium sera and anti-M. tuberculosis sera were analyzed for antibody-based reactivity by matrix-assisted laser desorption-ionization mass spectrometry (MALDI-TOF Mass) against M. tuberculosis proteins. The immunoreactive spots, which were attributed to the proteins HspX, GroES and CFP-10, were mostly located at 10 - 60 kDa and PI 4 - 6, subsequently Western blotting result proved that HspX and CFP-10 were specific to M. tuberculosis and ELISA testing result of 30 M. avium positive sera showed that GroES were cross-reactive to M. avium. Lastly, positive and negative tuberculosis reference sera and based on the mechanism of indirect ELISA, the specificity and the sensitivity of the methods targeting the antibodies HspX, GroES or CFP-10 were evaluated at 37% and 26%, 12% and 97%, 81% and 98%, respectively. The combination of these three antibody detection methods allowed to reached a specificity of 42%, and of 39% without taken into account of the method targeting the GroES antibody. Using proteomics approach, we found three M. tuberculosis specific antigens showed good potential in tuberculosis diagnosis, providing basic study for serodiagnosis of tuberculosis.
基金This work was supported by the Epidemic of Tuberculosis Recurrence and Types of Recent Recurrence in Western China(JY22-3-11),Chinese Center for Disease Control and Prevention.
文摘Summary What is already known about this topic?The coronavirus disease(COVID-19)pandemic could have a damaging impact on access to tuberculosis(TB)diagnosis and treatment.What is added by this report?The overall delay experienced by TB patients during the COVID-19 pandemic has shown a modest decrease in comparison to the period before the pandemic.Notably,higher patient delays were observed among agricultural workers and those identified through passive case-finding methods.Furthermore,the patient delay in eastern regions was shorter compared to western and central regions.
基金supported by National Natural Science Foundation of China(grant Nos.5187622151776225)and High-end Foreign Expert Introduction Project(grant Nos.G20190001270B18054).
文摘In this work,particle transport in a fully developed turbulent 90°bend flow at the"electrostatic equi-librium"state is simulated using large eddy simulation coupled with Lagrangian particle tracking technique.The flow Reynolds numbers(based on bulk velocity)considered is from 34000 to 58000.Three particle size 5,10 and 50μm are considered and their corresponding St number are from 2.2 to 547.Simulation results of the bend flow agree well with experimental data.The electrostatic field formed in the bend is symmetric in the spanwise direction but asymmetric in the vertical direction and radial direction,which is independent of Reynolds number.The minimum electrostatic field strength occurs at r/ra=0.25 near the inner wall of the bend.Particles transported in a bend gradually accumulate near the wall due to turbophoresis,such trend is improved by electrostatics.In addition,under the effect of electrostatics,the plume pattern of particle distribution disappeared.Particle concentration at the inner wall of the bend is higher than that at the outer wall,which depends on the combined effect of elec-trostatics and Dean vortices in the bend.
基金supported by the National Natural Science Foundation of China(grant No.51876225,51776221)the High-end Foreign Expert Introduction Project(grant No.G2021122007L,B18054).
文摘Particle behavior in a turbulent flow in a circular pipe with a bed height h=0.5R is studied at Reb=40,000 and for two sizes of particles(5μm and 50μm)using large eddy simulation,one-way coupled with a Lagrangian particle tracking technique.Turbulent secondary flows are found within the pipe,with the curved upper wall affecting the secondary flow formation giving rise to a pair of large upper vortices above two smaller vortices close to the pipe floor.The behavior of the two sizes of particle is found to be quite different.The 50μm particles deposit forming irregular elongated particle streaks close to the pipe floor,particularly at the center of the flow and the pipe corners due to the impact of the secondary flows.The deposition and resuspension rate of the 5μm particles is high near the center of the floor and at the pipe corners,while values for the 50μm particles are greatest near the corners.Near the curved upper wall of the pipe,the deposition rate of the 5μm particles increases in moving from the wall center to the corners,and is greater than that for the larger particles due to the effects of the secondary flow.The maximum resuspension rate of the smaller particles occurs above the pipe corners,with the 50μm particles showing their highest resuspension rate above and at the corners of the pipe.
基金All participants who contributed to the survey from the Centers for Disease Control and Prevention(CDC),hospitals,and health facilities.
文摘Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.What is added by this report?This manuscript reported the national representative total and breakdown costs associated with TB care in China.The total cost per patient was 1,185 USD,of which 88%was direct cost and 37%was incurred prior to TB treatment.
文摘Summary What is already known about this topic?Tuberculosis(TB)is a multisystem disease that might affect any organ.Currently,the National TB Program(NTP)issued by the State Council of China,only covers pulmonary tuberculosis(PTB),and the status of extrapulmonary tuberculosis(EPTB)remains unclear nationwide.What is added by this report?The survey conducted by China CDC reported that there were no specific health facilities responsible for diagnosis,treatment and management of EPTB in China,while more than half of counties thought it should be included into NTP.
基金This work was supported by National Natural Science Foun- dation of China （Grant Nos. 51376153 and 51406235） Science Foundation of China University of Petroleum, Beijing （Grant No. 2462013YJRC030）. We greatly acknowledge the suggestions given by Professor Chi-Hwa Wang （National University of Singapore） on the electrostatics characterization and equilibrium charge concept in this study.
基金supported by the Fujian Province Natural Science Foundation under Grant No.2012J01235
文摘In solid processing systems,electrostatic problems are commonly observed for granules of various shapes.However,a complete understanding of the basic dependence of electrostatic charge generation on particle shape has yet to be established.This observation motivated the present study on examining the effect of granular shape on electrostatics.In this study,polyvinyl chloride(PVC) granules(diameter 1.1-4.1 mm,in the shape of a triangle or trapezium) were first discharged to remove any residual charges and subsequently their electrostatic charging characteristics were studied by allowing a granule to slide along a pipe wall.Several factors such as granular front-facing angle,length-ratio,sliding area,sliding orientation,sliding times,and relative humidity were considered when studying their effects on the electrostatic charging of granules.It was found that triangular granules with smaller front-facing angles tended to generate more electrostatic charge.The amount of electrostatic charge increased with granular lengthratio and sliding area but decreased with humidity.In addition,granular sliding in the orientation of the front-facing angle(for triangular granules) or the short side(for trapezoidal granules) generated more electrostatic charge than that in the orientation of the long side.For both granule shapes,the electrostatic charge increased with granular sliding times and reached a saturated state after around 8-9 sliding movements.The saturated electrostatic charge increased with either granular length ratio or sliding area.
基金supported by the China National TB Program and the National Special Science and Technology Project for Major Infectious Diseases of China(2017ZX10201302007).
文摘Introduction:The year 2019 was crucial for the implementation of China’s National“13th 5-Year”Tuberculosis(TB)Control Plan.We conducted this study to evaluate the characteristics and progress towards controlling TB in China.Methods:We collected and analyzed the pulmonary tuberculosis(PTB)data of China between January 1,2015 and December 31,2019 from the National Notifiable Disease Reporting System(NNDRS).Results:In 2019,there were 775,764 PTB cases reported in NNDRS,of which 349,307 were bacteriologically-confirmed(Bac+)cases.The PTB case notification rate(CNR)was 55.55 per 100,000,and the Bac+CNR was 25.01 per 100,000.From 2018 to 2019,the number of PTB cases fell by 6.3%,but the number of Bac+cases increased by 25.9%.The annual decrease in the rate of reported PTB was 3.4% from 2015 to 2019.The 5 provincial-level administrative divisions(PLADs)with the highest PTB CNR were as follows:Tibet(182.38 per 100,000),Xinjiang(169.05 per 100,000),Qinghai(134.53 per 100,000),Guizhou(102.51 per 100,000),and Hainan(90.22 per 100,000).The rate of reported PTB was 74.84 per 100,000 for males and 35.40 per 100,000 for females.There were 8,116 cases(1.0%)among children aged 0–14 years,and 197,730 cases(25.5%)among adults aged 65 years and over.Of the reported cases,470,932 were farmers,which was the most common occupation at 60.7%.Conclusions and Implications for Public Health Practice:The TB epidemic has decreased dramatically year by year.Most PTB cases were in the central and western regions of China,and the high-risk groups were farmers and elderly people aged 65 years and over.
文摘Introduction:National Notifiable Disease Reporting System(NNDRS)plays an important role in the early detection and control of tuberculosis(TB)in China.This study analyzed the epidemiological characteristics of pulmonary tuberculosis(PTB)in Kashgar Prefecture,Xinjiang Uygur Autnomous Region,China from 2011 to 2020 to provide a scientific basis for developing TB control strategies and measures in Kashgar.Methods:The data were collected from the NNDRS,which included the geographical distribution,age,sex,occupation,and pathogenic classification of reported PTB cases in 12 counties/cities of Kashgar Prefecture from 2011 to 2020.Descriptive statistics were used to describe the characteristic of PTB epidemic in Kashgar.Results:There were 189,416 PTB cases reported during 2011–2020,with a mean annual PTB case notification rate(CNR)of 451.29/100,000.A rising trend in the rate of reported PTB between 2011 and 2017(χ2 trend=26.09,P<0.01)and a declining trend between 2018 and 2020(χ2 trend=314.44,P<0.01)were observed.The months with the highest reported number of PTB cases were March to May and November to December.The mean annual rate of reported PTB was 451.88/100,000 for males and 450.67/100,000 for females.In addition,19.76%of patients were bacteriologically-confirmed(Bac+)cases(37,425/189,416),and the mean annual Bac+CNR was 89.17/100,000,rising from 64.76/100,000 in 2011 to 139.12/100,000 in 2020(χ^(2)_(trend)=74.44,P<0.01).Conclusions:The CNR of reported PTB in Kashgar showed a significant declining trend in the past three years.Males,elderly population,winter and spring,and farmers as an occupation were the main factors associated with high incidence of tuberculosis in Kashgar.Targeted prevention and treatment of TB should be strengthened in key groups in this region.
基金JY 18-2-18 Acceptability of preventive treatment among close contacts of tuberculosis。
文摘Summary What is already known about this topic?The World Health Organization has estimated the impact of reductions in the performance of global tuberculosis(TB)detection and care on TB deaths.However,the actual impact of COVID-19 pandemic on TB deaths in China remains unclear.What is added by this report?The stringent public interventions to fight COVID-19 including lockdown led to more than 20%decrease of TB detection in China.
文摘What is already known about this topic?Tuberculosis(TB)notification data and the underreporting rate are major sources used in estimating TB incidence.China’s TB Information Management System(TBIMS)was launched in 2005 but has not yet been evaluated for sensitivity.What is added by this report?The average underreporting rate of pulmonary TB to TBIMS in selected facilities was 8.23%.However,provincial TB or infectious disease-specific health facilities,or general health facilities had higher underreporting rates.Children,migrants,and drug resistant TB patients had higher chances to be underreported than other populations.What are the implications for public health practice?Underreporting surveys should be routinely implemented in the future.This will be vital for enhancing TB reporting and the transfer mechanisms in TB or infectious disease-specific hospitals,or general hospitals and improving the case information registration procedures in designated health facilities(DHFs).
