At present,the cranes used at sea have several shortcomings in terms of flexibility,efficiency,and safety.Therefore,a floating multi-robot coordinated lifting system is proposed to fulfill the offshore lifting require...At present,the cranes used at sea have several shortcomings in terms of flexibility,efficiency,and safety.Therefore,a floating multi-robot coordinated lifting system is proposed to fulfill the offshore lifting requirements.First,the structure of the lifting system is established according to the lifting task,the kinematic model of the system is developed by using the D–H coordinate transformation,and the dynamic model is developed based on rigid-body dynamics and hydrodynamics.Then,the static and dynamic workspace of the lifting system are analyzed,and the solving steps of the workspace are given by using the Monte–Carlo method.The effect of the load mass and the maximum allowable tension of the cable on the workspace is examined by simulation.Results show that the lifting system has limited carrying capacity and a data reference for selecting the structural parameters by analyzing the factors affecting the workspace.Findings provide a basis for further research on the optimal design of structural parameters and the determination of safe configurations of the lifting system.展开更多
目的观察越婢汤对阿霉素肾病大鼠肾脏毛细血管通透性的影响,阐明其干预肾病综合征大鼠水肿的作用机制。方法采用尾静脉注射阿霉素建立大鼠肾病综合征模型。大鼠随机分为正常组、模型组及越婢汤低、中、高剂量组(6.6、11.1、22.2 g/kg),...目的观察越婢汤对阿霉素肾病大鼠肾脏毛细血管通透性的影响,阐明其干预肾病综合征大鼠水肿的作用机制。方法采用尾静脉注射阿霉素建立大鼠肾病综合征模型。大鼠随机分为正常组、模型组及越婢汤低、中、高剂量组(6.6、11.1、22.2 g/kg),灌胃给予相应药物14 d。给药结束后,检测肾脏毛细血管通透性、肾脏及皮肤干湿重比例,观察肾脏病理学变化,检测血清Scr、BUN、TC、ALB及尿液24 h UTP水平,ELISA法检测肾组织VEGF水平,免疫组化法检测肾组织VEGF、VEGFA、VEGFR2阳性表达,Western blot法检测肾组织VEGF、VEGFA、VEGFR2、p-ERK1/2、ERK1/2和Rap1蛋白表达。结果与模型组比较,越婢汤高剂量组大鼠肾脏及皮肤干湿重比例升高(P<0.05,P<0.01),VEGF和VEGFA蛋白表达降低(P<0.01);中、高剂量组大鼠肾脏毛细血管通透性,血清Scr、BUN、TC水平,尿液24 h UTP水平,肾组织VEGF水平和VEGFR2蛋白表达降低(P<0.05,P<0.01),ALB水平升高(P<0.01),肾组织病理学改善;越婢汤各剂量组大鼠肾组织p-ERK1/2/ERK1/2蛋白表达比值降低(P<0.01),Rap1蛋白表达升高(P<0.01)。结论越婢汤可以减轻阿霉素肾病大鼠皮肤和肾脏水肿,其作用机制和调控VEGF/ERK信号通路,改善肾脏毛细血管通透性有关。展开更多
The Tianxiu hydrothermal field(TXHF) located on Carlsberg Ridge is one of the few active ultramafic-hosted venting systems known in the Indian Ocean. Despite numerous investigations, there is limited understanding of ...The Tianxiu hydrothermal field(TXHF) located on Carlsberg Ridge is one of the few active ultramafic-hosted venting systems known in the Indian Ocean. Despite numerous investigations, there is limited understanding of its sulfide structure morphology, and the factors controlling the formation of TXHF are poorly understood. In this study, we conducted detailed seafloor mapping using visual data obtained by dives using the human-occupied vehicle(HOV) Jiaolong. The TXHF is found to be an active, off-axis, ultramafic-hosted, high-temperature hydrothermal area in which serpentine peridotite is exposed. Two main hydrothermal sites were identified, i.e., P and Y, both of which feature a complex of chimneys and beehive diffusers constituting a “chimney jungle” and isolated large steep-sided structures developed on flat-lying sulfide mounds. In addition, some sporadic inactive chimneys and outcrops of hydrothermal deposits were noted. The chimneys are rich in Fe and Zn sulfide, and lack the central fluid channel formed by focused high-temperature fluid flow. Hydrothermal venting at TXHF is likely related to low-angle detachment faults that focus and transport hydrothermal fluids away from a heat source along the valley wall. Our results complement and expand upon previous works concerning sulfide chimney morphology and their corresponding mineral paragenesis in ultramafic-hosted hydrothermal systems in the Indian Ocean and further our understanding of modern seafloor hydrothermal systems.展开更多
Stochastic heat conduction and thermal stress analysis of structures has received considerable attention in recent years.The propagation of uncertain thermal environments will lead to stochastic variations in temperat...Stochastic heat conduction and thermal stress analysis of structures has received considerable attention in recent years.The propagation of uncertain thermal environments will lead to stochastic variations in temperature fields and thermal stresses.Therefore,it is reasonable to consider the variability of thermal environments while conducting thermal analysis.However,for ambient thermal excitations,only stationary random processes have been investigated thus far.In this study,the highly efficient explicit time-domain method(ETDM)is proposed for the analysis of non-stationary stochastic transient heat conduction and thermal stress problems.The explicit time-domain expressions of thermal responses are first constructed for a thermoelastic body.Then the statistical moments of thermal displacements and stresses can be directly obtained based on the explicit expressions of thermal responses.A numerical example involving non-stationary stochastic internal heat generation rate is investigated.The accuracy and efficiency of the proposed method are validated by comparison with the Monte-Carlo simulation.展开更多
Our previous studies suggested a potential interaction between the POK erythroid myeloid ontogenic factor ZBTB7A and glucose transporter 1(GLUT1)in nasopharyngeal carcinoma(NPC).This study was designed to confirm the ...Our previous studies suggested a potential interaction between the POK erythroid myeloid ontogenic factor ZBTB7A and glucose transporter 1(GLUT1)in nasopharyngeal carcinoma(NPC).This study was designed to confirm the interaction and further evaluate the precise mechanism by which ZBTB7A and GLUT1 regulate NPC development.The binding sites between ZBTB7A and the promoter of GLUT1 were predicted by bioinformatics.Gene expression was measured by quantitative real-time polymerase chain reaction(qPCR),western blotting,and immunohistochemistry.The activities of key glycolysis enzymes,including hexokinase(HK),pyruvate kinase(PK),lactate dehydrogenase(LDH),and lactate,were detected using specific enzyme-linked immunosorbent assay kits.The connection between ZBTB7A and GLUT1 was analyzed by dual-luciferase reporter assay and chromatin immunoprecipitation-qPCR.The vitality,proliferation,and tumorigenicity of the cells expressing different levels of ZBTB7A were tested by adding the glycolysis inhibitor 2-deoxy-D-glucose(2-DG),followed by MTT,colorimetric focus forming,and xenograft assays,respectively.Our results showed that high expression of GLUT1 was associated with late-stage NPC.After constructing stably transfected cells with lentiviruses,ZBTB7A was effectively knocked down in 5-8F cells(RNAi-5-8F)and overexpressed in 6-10B cells(ZBTB7A-6-10B).The up-or downregulation of GLUT1 secondary to ZBTB7A changes was also limited.The vitality and proliferation of the cells expressing low ZBTB7A were notably blocked by 2-DG.The cells expressing high ZBTB7A were not very sensitive to 2-DG.The growth of RNAi-5-8F xenografts was strongly suppressed by 2-DG.The activities of HK,PK,and LDH were suppressed by 2-DG in the cells expressing low ZBTB7A.RNAi-5-8F cells had the lowest 2-DG-induced lactate production.ZBTB7A directly suppressed the promoter region of GLUT1 to regulate GLUT1 expression.Thus,ZBTB7A controls the 2-DG-induced inhibition of glycolysis by affecting GLUT1.展开更多
Summary What is already known on this topic?Rabies remains a serious public health problem in China.The only way to prevent the fatal disease was through timely and adequate post-exposure prophylaxis(PEP).What is adde...Summary What is already known on this topic?Rabies remains a serious public health problem in China.The only way to prevent the fatal disease was through timely and adequate post-exposure prophylaxis(PEP).What is added by this report?Among all the 126,133 cases visited Tianjin PEP clinics during 2020,more than 90%of the patients were injured by domestic dogs or cats,and about 70%of the animals received vaccination.Most outpatients have knowledge of rabies and show high compatibility with PEP.展开更多
Repairing glans dehiscence after failed hypospadias repair is challenging for pediatric surgeons.Here,we introduced and evaluated a newly modified Mathieu technique,Mathieu combined tunnel(MCT),which involves multiple...Repairing glans dehiscence after failed hypospadias repair is challenging for pediatric surgeons.Here,we introduced and evaluated a newly modified Mathieu technique,Mathieu combined tunnel(MCT),which involves multiple custom-designed flaps for the shortage of flap source material after repeated operations;we also constructed a tunnel to avoid the glans incision that may carry new risks of dehiscence.This retrospective study included 26 patients who were consecutively admitted to the First Affiliated Hospital of Sun Yat-Sen University(Guangzhou,China)for glans dehiscence repair after failed hypospadias repair from October 2014 to October 2020;sixteen patients underwent surgery using the MCT(MCT group)and ten patients underwent surgery using the tubularized incised plate(TIP)technique(TIP group).The operative time,blood loss,postoperative complications,normal urethral meatus rate,success rate,and Hypospadias Objective Penile Evaluation(HOPE)score were compared between the two groups.The MCT group achieved an overall satisfactory penile appearance and voiding function,with a higher rate of normal urethral meatus(15/16,93.8%)and a lower rate of glans dehiscence(1/16,6.2%),compared with the TIP group(70.0%and 30.0%,respectively).However,these differences were not statistically significant,possibly because of the limited number of patients(all P>0.05).Mean postoperative HOPE scores were similar in the MCT group(mean±standard deviation:8.83±0.89)and TIP group(8.94±0.57)(P>0.05).No significant differences were found between the two groups in terms of blood loss and success rate,nor in the rates of various complications(e.g.,fistula,urethral stricture,and glans dehiscence).In conclusion,the MCT technique appears to be feasible and reliable for repairing glans dehiscence after failed hypospadias repair.展开更多
Na_(4-δ)Ni Te O_(6) is a rare example in the transition-metal tellurate family of realizing an S=1 spin-chain structure.By performing neutron powder diffraction measurements,the ground-state magnetic structure of Na_...Na_(4-δ)Ni Te O_(6) is a rare example in the transition-metal tellurate family of realizing an S=1 spin-chain structure.By performing neutron powder diffraction measurements,the ground-state magnetic structure of Na_(4-δ)Ni Te O_(6) is determined.These measurements reveal that below T_N~6.8(2)K,the Ni^(2+) moments form a screwed ferromagnetic(FM)spin-chain structure running along the crystallographic a axis but these FM spin chains are coupled antiferromagnetically along the b and c directions,giving rise to a magnetic propagation vector of k=(0,1/2,1/2).This zigzag magnetic order is well supported by first-principles calculations.The moment size of Ni^(2+) spins is determined to be 2.1(1) μ_(B) at 3 K,suggesting a significant quenching of the orbital moment due to the crystalline electric field(CEF)effect.The previously reported metamagnetic transition near H_(c)~0.1 T can be understood as a field-induced spin-flip transition.The relatively easy tunability of the dimensionality of its magnetism by external parameters makes Na_(4-δ)Ni Te O_(6)a promising candidate for further exploring various types of novel spin-chain physics.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.51965032the National Natural Science Foundation of Gansu Province of China under Grant No.22JR5RA319+1 种基金the Science and Technology Foundation of Gansu Province of China under Grant No.21YF5WA060the Excellent Doctoral Student Foundation of Gansu Province of China under Grant No.23JRRA842。
文摘At present,the cranes used at sea have several shortcomings in terms of flexibility,efficiency,and safety.Therefore,a floating multi-robot coordinated lifting system is proposed to fulfill the offshore lifting requirements.First,the structure of the lifting system is established according to the lifting task,the kinematic model of the system is developed by using the D–H coordinate transformation,and the dynamic model is developed based on rigid-body dynamics and hydrodynamics.Then,the static and dynamic workspace of the lifting system are analyzed,and the solving steps of the workspace are given by using the Monte–Carlo method.The effect of the load mass and the maximum allowable tension of the cable on the workspace is examined by simulation.Results show that the lifting system has limited carrying capacity and a data reference for selecting the structural parameters by analyzing the factors affecting the workspace.Findings provide a basis for further research on the optimal design of structural parameters and the determination of safe configurations of the lifting system.
文摘目的观察越婢汤对阿霉素肾病大鼠肾脏毛细血管通透性的影响,阐明其干预肾病综合征大鼠水肿的作用机制。方法采用尾静脉注射阿霉素建立大鼠肾病综合征模型。大鼠随机分为正常组、模型组及越婢汤低、中、高剂量组(6.6、11.1、22.2 g/kg),灌胃给予相应药物14 d。给药结束后,检测肾脏毛细血管通透性、肾脏及皮肤干湿重比例,观察肾脏病理学变化,检测血清Scr、BUN、TC、ALB及尿液24 h UTP水平,ELISA法检测肾组织VEGF水平,免疫组化法检测肾组织VEGF、VEGFA、VEGFR2阳性表达,Western blot法检测肾组织VEGF、VEGFA、VEGFR2、p-ERK1/2、ERK1/2和Rap1蛋白表达。结果与模型组比较,越婢汤高剂量组大鼠肾脏及皮肤干湿重比例升高(P<0.05,P<0.01),VEGF和VEGFA蛋白表达降低(P<0.01);中、高剂量组大鼠肾脏毛细血管通透性,血清Scr、BUN、TC水平,尿液24 h UTP水平,肾组织VEGF水平和VEGFR2蛋白表达降低(P<0.05,P<0.01),ALB水平升高(P<0.01),肾组织病理学改善;越婢汤各剂量组大鼠肾组织p-ERK1/2/ERK1/2蛋白表达比值降低(P<0.01),Rap1蛋白表达升高(P<0.01)。结论越婢汤可以减轻阿霉素肾病大鼠皮肤和肾脏水肿,其作用机制和调控VEGF/ERK信号通路,改善肾脏毛细血管通透性有关。
基金The National Key Research and Development Program of China under contract No. 2017YFC0306603the National Key Research and Development Program of China under contract No. 2021YFC2801705+2 种基金the Scientific Research Fund of the Second Institute of OceanographyMinistry of Natural Resources under contract Nos JG1905 and SZ2201the National Natural Science Foundation of China under contract No. 41806076。
文摘The Tianxiu hydrothermal field(TXHF) located on Carlsberg Ridge is one of the few active ultramafic-hosted venting systems known in the Indian Ocean. Despite numerous investigations, there is limited understanding of its sulfide structure morphology, and the factors controlling the formation of TXHF are poorly understood. In this study, we conducted detailed seafloor mapping using visual data obtained by dives using the human-occupied vehicle(HOV) Jiaolong. The TXHF is found to be an active, off-axis, ultramafic-hosted, high-temperature hydrothermal area in which serpentine peridotite is exposed. Two main hydrothermal sites were identified, i.e., P and Y, both of which feature a complex of chimneys and beehive diffusers constituting a “chimney jungle” and isolated large steep-sided structures developed on flat-lying sulfide mounds. In addition, some sporadic inactive chimneys and outcrops of hydrothermal deposits were noted. The chimneys are rich in Fe and Zn sulfide, and lack the central fluid channel formed by focused high-temperature fluid flow. Hydrothermal venting at TXHF is likely related to low-angle detachment faults that focus and transport hydrothermal fluids away from a heat source along the valley wall. Our results complement and expand upon previous works concerning sulfide chimney morphology and their corresponding mineral paragenesis in ultramafic-hosted hydrothermal systems in the Indian Ocean and further our understanding of modern seafloor hydrothermal systems.
基金funded by the National Natural Science Foundation of China (51678252)the Guangzhou Science and Technology Project (201804020069)
文摘Stochastic heat conduction and thermal stress analysis of structures has received considerable attention in recent years.The propagation of uncertain thermal environments will lead to stochastic variations in temperature fields and thermal stresses.Therefore,it is reasonable to consider the variability of thermal environments while conducting thermal analysis.However,for ambient thermal excitations,only stationary random processes have been investigated thus far.In this study,the highly efficient explicit time-domain method(ETDM)is proposed for the analysis of non-stationary stochastic transient heat conduction and thermal stress problems.The explicit time-domain expressions of thermal responses are first constructed for a thermoelastic body.Then the statistical moments of thermal displacements and stresses can be directly obtained based on the explicit expressions of thermal responses.A numerical example involving non-stationary stochastic internal heat generation rate is investigated.The accuracy and efficiency of the proposed method are validated by comparison with the Monte-Carlo simulation.
基金The study was supported by the Natural Science Foundation of Guangxi Province(2016GXNSFBA380144)Guangxi Science and Technology Base and Talent Project(GuiKe-AD20297069)National Natural Science Foundation of China(81960493).
文摘Our previous studies suggested a potential interaction between the POK erythroid myeloid ontogenic factor ZBTB7A and glucose transporter 1(GLUT1)in nasopharyngeal carcinoma(NPC).This study was designed to confirm the interaction and further evaluate the precise mechanism by which ZBTB7A and GLUT1 regulate NPC development.The binding sites between ZBTB7A and the promoter of GLUT1 were predicted by bioinformatics.Gene expression was measured by quantitative real-time polymerase chain reaction(qPCR),western blotting,and immunohistochemistry.The activities of key glycolysis enzymes,including hexokinase(HK),pyruvate kinase(PK),lactate dehydrogenase(LDH),and lactate,were detected using specific enzyme-linked immunosorbent assay kits.The connection between ZBTB7A and GLUT1 was analyzed by dual-luciferase reporter assay and chromatin immunoprecipitation-qPCR.The vitality,proliferation,and tumorigenicity of the cells expressing different levels of ZBTB7A were tested by adding the glycolysis inhibitor 2-deoxy-D-glucose(2-DG),followed by MTT,colorimetric focus forming,and xenograft assays,respectively.Our results showed that high expression of GLUT1 was associated with late-stage NPC.After constructing stably transfected cells with lentiviruses,ZBTB7A was effectively knocked down in 5-8F cells(RNAi-5-8F)and overexpressed in 6-10B cells(ZBTB7A-6-10B).The up-or downregulation of GLUT1 secondary to ZBTB7A changes was also limited.The vitality and proliferation of the cells expressing low ZBTB7A were notably blocked by 2-DG.The cells expressing high ZBTB7A were not very sensitive to 2-DG.The growth of RNAi-5-8F xenografts was strongly suppressed by 2-DG.The activities of HK,PK,and LDH were suppressed by 2-DG in the cells expressing low ZBTB7A.RNAi-5-8F cells had the lowest 2-DG-induced lactate production.ZBTB7A directly suppressed the promoter region of GLUT1 to regulate GLUT1 expression.Thus,ZBTB7A controls the 2-DG-induced inhibition of glycolysis by affecting GLUT1.
文摘Summary What is already known on this topic?Rabies remains a serious public health problem in China.The only way to prevent the fatal disease was through timely and adequate post-exposure prophylaxis(PEP).What is added by this report?Among all the 126,133 cases visited Tianjin PEP clinics during 2020,more than 90%of the patients were injured by domestic dogs or cats,and about 70%of the animals received vaccination.Most outpatients have knowledge of rabies and show high compatibility with PEP.
基金supported by grants from the National Natural Science Foundation of China(No.81971314)。
文摘Repairing glans dehiscence after failed hypospadias repair is challenging for pediatric surgeons.Here,we introduced and evaluated a newly modified Mathieu technique,Mathieu combined tunnel(MCT),which involves multiple custom-designed flaps for the shortage of flap source material after repeated operations;we also constructed a tunnel to avoid the glans incision that may carry new risks of dehiscence.This retrospective study included 26 patients who were consecutively admitted to the First Affiliated Hospital of Sun Yat-Sen University(Guangzhou,China)for glans dehiscence repair after failed hypospadias repair from October 2014 to October 2020;sixteen patients underwent surgery using the MCT(MCT group)and ten patients underwent surgery using the tubularized incised plate(TIP)technique(TIP group).The operative time,blood loss,postoperative complications,normal urethral meatus rate,success rate,and Hypospadias Objective Penile Evaluation(HOPE)score were compared between the two groups.The MCT group achieved an overall satisfactory penile appearance and voiding function,with a higher rate of normal urethral meatus(15/16,93.8%)and a lower rate of glans dehiscence(1/16,6.2%),compared with the TIP group(70.0%and 30.0%,respectively).However,these differences were not statistically significant,possibly because of the limited number of patients(all P>0.05).Mean postoperative HOPE scores were similar in the MCT group(mean±standard deviation:8.83±0.89)and TIP group(8.94±0.57)(P>0.05).No significant differences were found between the two groups in terms of blood loss and success rate,nor in the rates of various complications(e.g.,fistula,urethral stricture,and glans dehiscence).In conclusion,the MCT technique appears to be feasible and reliable for repairing glans dehiscence after failed hypospadias repair.
基金supported by the National Natural Science Foundation of China(Grant Nos.12074023,12004020,11834014,11974036,and12074024)Fundamental Research Funds for the Central Universities in China。
文摘Na_(4-δ)Ni Te O_(6) is a rare example in the transition-metal tellurate family of realizing an S=1 spin-chain structure.By performing neutron powder diffraction measurements,the ground-state magnetic structure of Na_(4-δ)Ni Te O_(6) is determined.These measurements reveal that below T_N~6.8(2)K,the Ni^(2+) moments form a screwed ferromagnetic(FM)spin-chain structure running along the crystallographic a axis but these FM spin chains are coupled antiferromagnetically along the b and c directions,giving rise to a magnetic propagation vector of k=(0,1/2,1/2).This zigzag magnetic order is well supported by first-principles calculations.The moment size of Ni^(2+) spins is determined to be 2.1(1) μ_(B) at 3 K,suggesting a significant quenching of the orbital moment due to the crystalline electric field(CEF)effect.The previously reported metamagnetic transition near H_(c)~0.1 T can be understood as a field-induced spin-flip transition.The relatively easy tunability of the dimensionality of its magnetism by external parameters makes Na_(4-δ)Ni Te O_(6)a promising candidate for further exploring various types of novel spin-chain physics.
