With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as ...With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as a new method for enhancing permeability of coal seam to improve gas extraction,features in the advantages of high efficiency,eco-friendly,and low cost.In order to better utilize the CSW into gas extraction in coal mine,the mechanism and feasibility of CSW enhanced extraction need to be studied.In this paper,the basic principles,the experimental tests,the mathematical models,and the on-site tests of CSW fracturing coal seams are reviewed,thereby its future research directions are provided.Based on the different media between electrodes,the CSW can be divided into three categories:hydraulic effect,wire explosion and excitation of energetic materials by detonating wire.During the process of propagation and attenuation of the high-energy shock wave in coal,the shock wave and bubble pulsation work together to produce an enhanced permeability effect on the coal seam.The stronger the strength of the CSW is,the more cracks created in the coal is,and the greater the length,width and area of the cracks being.The repeated shock on the coal seam is conducive to the formation of complex network fracture system as well as the reduction of coal seam strength,but excessive shock frequency will also damage the coal structure,resulting in the limited effect of the enhanced gas extraction.Under the influence of ground stress,the crack propagation in coal seam will be restrained.The difference of horizontal principal stress has a significant impact on the shape,propagation direction and connectivity of the CSW induced cracks.The permeability enhancement effect of CSW is affected by the breakage degree of coal seam.The shock wave is absorbed by the broken coal,which may hinder the propagation of CSW,resulting in a poor effect of permeability enhancement.When arranging two adjacent boreholes for CSW permeability enhancement test,the spacing of boreholes should not be too close,which may lead to negative pressure mutual pulling in the early stage of drainage.At present,the accurate method for effectively predicting the CSW permeability enhanced range should be further investigated.展开更多
Oversea purchase has got rapid development as a new industry in our country. But its problems are increasingly prominent. This thesis aims at finding the problems and roots which hinder its development by analyzing th...Oversea purchase has got rapid development as a new industry in our country. But its problems are increasingly prominent. This thesis aims at finding the problems and roots which hinder its development by analyzing the development situation of current oversea purchase. In addition, this thesis will look for countermeasures which are beneficial to its healthy development and promote the free development of foreign trade in our country.展开更多
Here,we report a previously unrecognized syndromic neurodevelopmental disorder associated with biallelic loss-of-function variants in the RBM42 gene.The patient is a 2-year-old female with severe central nervous syste...Here,we report a previously unrecognized syndromic neurodevelopmental disorder associated with biallelic loss-of-function variants in the RBM42 gene.The patient is a 2-year-old female with severe central nervous system(CNs)abnormalities,hypotonia,hearing loss,congenital heart defects,and dysmorphic facial features.Familial whole-exome sequencing(WEs)reveals that the patient has two compound heterozygous variants,c.304C>T(p.R102*)and c.1312G>A(p.A438T),in the RBM42 gene which encodes an integral component of splicing complex in the RNA-binding motif protein family.The p.A438T variant is in the RRM domain which impairs RBM42 pro-tein stability in vivo.Additionally,p.A438T disrupts the interaction of RBM42 with hnRNP K,which is the causa-tive gene for Au-Kline syndrome with overlapping disease characteristics seen in the index patient.The human R102*or A438T mutant protein failed to fully rescue the growth defects of RBM42 ortholog knockout△FgRbp1 in Fusarium while it was rescued by the wild-type(WT)human RBM42.A mouse model carying Rbm42 compound heterozygous variants,c.280C>T(p.Q94*)and c.1306_1308delinsACA(p.A436T),demonstrated gross fetal develop-mental defects and most of the double mutant animals died by E13.5.RNA-seq data confirmed that Rbm42 was involved in neurological and myocardial functions with an essential role in alternative splicing(As).Overall,we present clinical,genetic,and functional data to demonstrate that defects in RBM42 constitute the underlying etiology of a new neurodevelopmental disease which links the dysregulation of global AS to abnormal embryonic development.展开更多
Background:Early-stage ampullary adenomas have only been reported in a small case series on endoscopic management.Hence,this study aimed to evaluate the long-term outcomes of early ampullary adenoma with endoscopic ma...Background:Early-stage ampullary adenomas have only been reported in a small case series on endoscopic management.Hence,this study aimed to evaluate the long-term outcomes of early ampullary adenoma with endoscopic management and identify the risk factors for acute pancreatitis after endoscopic papillectomy(EP).Methods:In this study,115 patients who underwent EP at Changhai Hospital(Shanghai,China)between January 2012 and December 2018 were retrospectively analysed.Endoscopy was performed at 1,3,6,and 12months after EP.Data were statistically analysed using the t-test or the Mann–Whitney U test.Results:A total of 107 patients were included in this study and the follow-up period was 75643 months.The average age of the 107 patients was 54.6 years and the average tumor size was 17mm.The average age of the patients(53.7610.7 years vs 55.2610.5 years,P=0.482),minimum tumor size(13 vs 19mm,P=0.063),and complete resection rate(84.78%vs 85.25%,P=0.947)did not differ significantly between the stent placement and non-stent placement groups.Post-EP acute pancreatitis rates in the non-stent placement and stent placement groups were 11.48%and 4.35%,respectively.The risk of post-EP acute pancreatitis was significantly associated with the preoperative carcinoembryonic antigen level in univariate analysis,but not in multivariate analysis.The risk of post-EP acute pancreatitis was not significantly associated with the placement of the pancreatic stent in either univariate or multivariate analysis.Moreover,delayed proximal pancreatic duct stenosis was not noted in either group during long-term follow-up.Conclusions:EP is a satisfactory option for treating adenomas of the ampulla of the duodenum.展开更多
What is already known about this topic?Men who have sex with men(MSM)bear a disproportionate burden of new human immunodeficiency virus(HIV)infections and young MSM demonstrate parallel internet-driven HIV incident in...What is already known about this topic?Men who have sex with men(MSM)bear a disproportionate burden of new human immunodeficiency virus(HIV)infections and young MSM demonstrate parallel internet-driven HIV incident infection and dynamic social network.What is added by this report?The HIV positive prevalence and incidence among college MSM were 3.8%and 2.9 per 100 person-years,respectively,while these rates were 13.9%and 10.5 per 100 person-years,respectively,among their social contacts.The overall HIV positive prevalence was 7.2%in Northeast China.HIV-positive MSM have comparatively more social contacts than HIVseronegative MSM.What are the implications for public health practice?Hyper-linkages found in app-based social networks play an important role in HIV transmission via risky sexual behavior and suggest options for online intervention to promote HIV prevention.展开更多
Summary What is already known about this topic?Human immunodeficiency virus(HIV)testing is a critical tool in reducing HIV transmission among men who have sex with men(MSM);young MSM frequently use mobile phone applic...Summary What is already known about this topic?Human immunodeficiency virus(HIV)testing is a critical tool in reducing HIV transmission among men who have sex with men(MSM);young MSM frequently use mobile phone applications and participate in social hook-ups.展开更多
基金National Natural Science Foundation of China(52004117,52174117 and 52074146)Postdoctoral Science Foundation of China(2021T140290 and 2020M680975)Basic scientific research project of Liaoning Provincial Department of Education(JYTZD2023073).
文摘With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as a new method for enhancing permeability of coal seam to improve gas extraction,features in the advantages of high efficiency,eco-friendly,and low cost.In order to better utilize the CSW into gas extraction in coal mine,the mechanism and feasibility of CSW enhanced extraction need to be studied.In this paper,the basic principles,the experimental tests,the mathematical models,and the on-site tests of CSW fracturing coal seams are reviewed,thereby its future research directions are provided.Based on the different media between electrodes,the CSW can be divided into three categories:hydraulic effect,wire explosion and excitation of energetic materials by detonating wire.During the process of propagation and attenuation of the high-energy shock wave in coal,the shock wave and bubble pulsation work together to produce an enhanced permeability effect on the coal seam.The stronger the strength of the CSW is,the more cracks created in the coal is,and the greater the length,width and area of the cracks being.The repeated shock on the coal seam is conducive to the formation of complex network fracture system as well as the reduction of coal seam strength,but excessive shock frequency will also damage the coal structure,resulting in the limited effect of the enhanced gas extraction.Under the influence of ground stress,the crack propagation in coal seam will be restrained.The difference of horizontal principal stress has a significant impact on the shape,propagation direction and connectivity of the CSW induced cracks.The permeability enhancement effect of CSW is affected by the breakage degree of coal seam.The shock wave is absorbed by the broken coal,which may hinder the propagation of CSW,resulting in a poor effect of permeability enhancement.When arranging two adjacent boreholes for CSW permeability enhancement test,the spacing of boreholes should not be too close,which may lead to negative pressure mutual pulling in the early stage of drainage.At present,the accurate method for effectively predicting the CSW permeability enhanced range should be further investigated.
文摘Oversea purchase has got rapid development as a new industry in our country. But its problems are increasingly prominent. This thesis aims at finding the problems and roots which hinder its development by analyzing the development situation of current oversea purchase. In addition, this thesis will look for countermeasures which are beneficial to its healthy development and promote the free development of foreign trade in our country.
基金supported by the National Key Research.and Development Program of China (Nos.2020YFA0804000,2021YFC2701002 and 2022YFC2703702)the National Natural Science Foundation of China (Nos.81971344,81901495,82071661,82171677,82088102,82192864 and 82271898)+7 种基金the Science and Technology Commission of Shanghai Municipality (Nos.17411972900,23ZR1408000,21Y21901002 and 22S31901500)CAMS Innovation Fund for Medical Sciences (2019-I2M-5-064)Shanghai Municipal Commission of Health and family planning (202140110 and 20215Y0216)Collaborative Innovation Program of Shanghai Municipal Health Commission (2020CXJQ01)Clinical Research Plan of SHDC (SHDC2020CR1008A)Shanghai Clinical Research Center for Gynecological Diseases (22MC1940200)Shanghai Urogenital Systemn Diseases Research Center (2022ZZ01012)Shanghai Frontiers Science Research Center of Reproduction and Development.
文摘Here,we report a previously unrecognized syndromic neurodevelopmental disorder associated with biallelic loss-of-function variants in the RBM42 gene.The patient is a 2-year-old female with severe central nervous system(CNs)abnormalities,hypotonia,hearing loss,congenital heart defects,and dysmorphic facial features.Familial whole-exome sequencing(WEs)reveals that the patient has two compound heterozygous variants,c.304C>T(p.R102*)and c.1312G>A(p.A438T),in the RBM42 gene which encodes an integral component of splicing complex in the RNA-binding motif protein family.The p.A438T variant is in the RRM domain which impairs RBM42 pro-tein stability in vivo.Additionally,p.A438T disrupts the interaction of RBM42 with hnRNP K,which is the causa-tive gene for Au-Kline syndrome with overlapping disease characteristics seen in the index patient.The human R102*or A438T mutant protein failed to fully rescue the growth defects of RBM42 ortholog knockout△FgRbp1 in Fusarium while it was rescued by the wild-type(WT)human RBM42.A mouse model carying Rbm42 compound heterozygous variants,c.280C>T(p.Q94*)and c.1306_1308delinsACA(p.A436T),demonstrated gross fetal develop-mental defects and most of the double mutant animals died by E13.5.RNA-seq data confirmed that Rbm42 was involved in neurological and myocardial functions with an essential role in alternative splicing(As).Overall,we present clinical,genetic,and functional data to demonstrate that defects in RBM42 constitute the underlying etiology of a new neurodevelopmental disease which links the dysregulation of global AS to abnormal embryonic development.
基金supported by the National Natural Science Foundation of China(No.82100661)the school project of Naval Medical University(2021QN31).
文摘Background:Early-stage ampullary adenomas have only been reported in a small case series on endoscopic management.Hence,this study aimed to evaluate the long-term outcomes of early ampullary adenoma with endoscopic management and identify the risk factors for acute pancreatitis after endoscopic papillectomy(EP).Methods:In this study,115 patients who underwent EP at Changhai Hospital(Shanghai,China)between January 2012 and December 2018 were retrospectively analysed.Endoscopy was performed at 1,3,6,and 12months after EP.Data were statistically analysed using the t-test or the Mann–Whitney U test.Results:A total of 107 patients were included in this study and the follow-up period was 75643 months.The average age of the 107 patients was 54.6 years and the average tumor size was 17mm.The average age of the patients(53.7610.7 years vs 55.2610.5 years,P=0.482),minimum tumor size(13 vs 19mm,P=0.063),and complete resection rate(84.78%vs 85.25%,P=0.947)did not differ significantly between the stent placement and non-stent placement groups.Post-EP acute pancreatitis rates in the non-stent placement and stent placement groups were 11.48%and 4.35%,respectively.The risk of post-EP acute pancreatitis was significantly associated with the preoperative carcinoembryonic antigen level in univariate analysis,but not in multivariate analysis.The risk of post-EP acute pancreatitis was not significantly associated with the placement of the pancreatic stent in either univariate or multivariate analysis.Moreover,delayed proximal pancreatic duct stenosis was not noted in either group during long-term follow-up.Conclusions:EP is a satisfactory option for treating adenomas of the ampulla of the duodenum.
基金supported in part by National Natural Science Foundation of China(72061137007,81673232)Dr.Vermund supported in part by NIH grant number P30MH062294.
文摘What is already known about this topic?Men who have sex with men(MSM)bear a disproportionate burden of new human immunodeficiency virus(HIV)infections and young MSM demonstrate parallel internet-driven HIV incident infection and dynamic social network.What is added by this report?The HIV positive prevalence and incidence among college MSM were 3.8%and 2.9 per 100 person-years,respectively,while these rates were 13.9%and 10.5 per 100 person-years,respectively,among their social contacts.The overall HIV positive prevalence was 7.2%in Northeast China.HIV-positive MSM have comparatively more social contacts than HIVseronegative MSM.What are the implications for public health practice?Hyper-linkages found in app-based social networks play an important role in HIV transmission via risky sexual behavior and suggest options for online intervention to promote HIV prevention.
基金National Natural Science Foundation of China(72061137007,81673232)NIH grant number P30MH062294.
文摘Summary What is already known about this topic?Human immunodeficiency virus(HIV)testing is a critical tool in reducing HIV transmission among men who have sex with men(MSM);young MSM frequently use mobile phone applications and participate in social hook-ups.
