In this paper,we present an overview of numerical simulation methods for the flow around typical underwater vehicles at high Reynolds numbers,which highlights the dominant flow structures in different regions of inter...In this paper,we present an overview of numerical simulation methods for the flow around typical underwater vehicles at high Reynolds numbers,which highlights the dominant flow structures in different regions of interest.This overview covers the forebody,midbody,stern,wake region,and appendages and summarizes flow phenomena,including laminar-to-turbulent transition,turbulent boundary layers,flow under the influence of curvatures,wake interactions,and all associated complex vortex structures.Furthermore,the current issues and challenges of capturing these flow structures are addressed.This overview provides a deep insight into the use of numerical simulation methods,including the Reynolds-averaged Navier–Stokes(RANS)method,large eddy simulation(LES)method,and the hybrid RANS/LES method,and evaluates their applicability in capturing detailed flow features.展开更多
Background:The aim of this study is to investigate the mechanism of action underlying the therapeutic effects of the national patent Chinese medicine compound“Qiangxinhuoli prescription(QXHLF)”on chronic heart failu...Background:The aim of this study is to investigate the mechanism of action underlying the therapeutic effects of the national patent Chinese medicine compound“Qiangxinhuoli prescription(QXHLF)”on chronic heart failure(CHF).Methods:In vitro,the H 9 C 2 cell model was induced by ANGII,and cell proliferation and related protein expression were detected by Cell Counting Kit-8 and Western blot.In vivo,A rat model of CHF was prepared by ligation of the left anterior descending coronary artery.The effects of QXHLF on cardiac function in CHF rats were evaluated by cardiac index,hemodynamic changes,enzyme-linked immunosorbent assay,hematoxylin-eosin staining,immunohistochemistry,Western blot and RT-PCR.The expression of pro-apoptotic factors and anti-apoptotic factors,as well as TGFβ1,p-p38,TAK 1 mRNA,and protein,were detected.Results:In vitro,QXHLF has a significant inhibitory effect on the proliferation of H 9 C 2 cells.QXHLF can reduce the expression levels of TAK 1,TGFβ1,p-p38,Caspase3 and BAX proteins in H 9 C 2 cells,and increase the expression level of BCL 2 protein.In vivo,QXHLF has the potential to increase left ventricular systolic pressure,m aximum rate of change in left ventricular pressure while decreasing left ventricular end diastolic pressure,and inhibiting the serum levels of brain natriuretic peptide.Moreover,QXHLF exhibits significant improvements in the pathological alterations of myocardial cells and fibers in CHF rats,leading to enhanced myocardial tissue morphology and notable advantages in combating myocardial fibrosis.QXHLF can reduce the levels of BAX and Caspase3 and up-regulate the expression of BCL 2,thereby inhibiting cardiomyocyte apoptosis.Furthermore,QXHLF demonstrates inhibitory effects on the mRNA and protein expression levels of TGFβ1,TAK 1,and p-p38 in the heart tissue of the CHF rat model.Conclusion:These findings indicate that QXHLF has a therapeutic effect on CHF by inhibiting the p38-MAPK signaling pathway,reducing myocardial fibrosis,preventing apoptosis,inhibiting cell proliferation,and restoring myocardial injury.展开更多
[Objectives]To study the anti-inflammatory and analgesic effects of Millettia speciosa and Tinpspora sinensis and their compatibility.[Methods](i)In the glacial acetic acid writhing experiment,60 SPF-grade Kunming mic...[Objectives]To study the anti-inflammatory and analgesic effects of Millettia speciosa and Tinpspora sinensis and their compatibility.[Methods](i)In the glacial acetic acid writhing experiment,60 SPF-grade Kunming mice were adopted,and the mice were randomly divided into 6 groups at male-female ratio of 1∶1,namely,the blank control group,M.speciosa group,T.sinensis group,M.speciosa compatible with T.sinensis group at the ratio of 1∶2(expressed as 1∶2 compatibility group),M.speciosa compatible with T.sinensis group at the ratio of 1∶1(expressed as 1∶1 compatibility group),and M.speciosa compatible with T.sinensis group at the ratio of 2∶1(expressed as 2∶1 compatibility group),12 mice for each group.Mice of the experimental groups were administered at a dose of 20 mL/kg,and the corresponding concentration of the Chinese medicine extract was given at 1 g/mL.The control group was administered with an equal volume of 0.9%physiological saline,and was intragastrically administered once every 24 h for 14 d.After intragastric administration for one hour on day 14,intraperitoneal injection of 0.5%glacial acetic acid solution was performed to induce pain.(ii)In the hot plate experiment,60 Kunming female SPF mice were adopted,grouped,intragastrically administered with the same glacial acetic acid writhing experiment for 14 d.After intragastric administration for one hour on day 14,the mice were placed on a hot plate apparatus at(55±0.5)℃.to measure the time of licking their hind feet.(iii)In the anti-inflammatory experiment,60 Kunming SPF mice were adopted,grouped,intragastrically administered with the same glacial acetic acid writhing experiment for 14 d.After intragastric administration for one hour on day 14,xylylene was administered to the left ears of mice at a dose of 50μL/piece to induce inflammation.[Results](i)In the glacial acetic acid writhing experiment,compared with the blank control group,the experimental group showed analgesic effects.Specifically,M.speciosa group,T.sinensis group,1∶2 compatibility group,1∶1 compatibility group,2∶1 compatibility group showed significant effect(P<0.05),the writhing inhibition rate was 17.65%,20.59%,29.41%,26.47%,and 44.12%,respectively,and 2∶1 compatibility group showed the most significant analgesic effects.(ii)In the hot plate experiment,compared with the control group,all experimental groups showed analgesic effect.Specifically,M.speciosa group,T.sinensis group,1∶2 compatibility group,1∶1 compatibility group,2∶1 compatibility group showed significant effect(P<0.05),the pain threshold improvement rates were 16.13%,14.55%,14.96%,29.95%,and 58.68%,respectively,and 2∶1 compatibility group showed the most significant analgesic effect.(iii)In the anti-inflammatory experiment,the swelling degree of the 1∶2 compatibility group was significantly different from that of the blank control group,M.speciosa group,T.sinensis group(P<0.05).and 1∶2 compatibility group showed the most significant anti-inflammatory effect.[Conclusions]M.speciosa,T.sinensis,and their compatibility had anti-inflammatory and analgesic effects.The 2∶1 compatibility group had the best analgesic effects,and 1∶2 compatibility group had the best anti-inflammatory effects.展开更多
This paper presents a numerical investigation of the interaction among wave,flow and a fixed cylinder using the naoe-FOAM-SJTU solver,which is a viscous solver for hydrodynamics based on OpenFOAM.The simulation consid...This paper presents a numerical investigation of the interaction among wave,flow and a fixed cylinder using the naoe-FOAM-SJTU solver,which is a viscous solver for hydrodynamics based on OpenFOAM.The simulation considers the strong nonlinear interaction among a regular wave,flow,and a single fixed cylinder due to viscosity,which is common in offshore structures.The study focus on the vortex induced by viscosity and its significant role in hydrodynamic performance computation.A mesh convergence study is conducted prior to the simulation,and a proper set of mesh is chosen.The simultaneous generation of the regular wave and flow is realized using the numerical field boundary,and the wave propagation is validated.The results of wave elevation and pressures captured by wave gauges and probes around the fixed cylinder are compared with experiment results.The structure of vortices is displayed at significant times,and the phenomena of wave elevation and pressure changes around the cylinder are analyzed in detail using the Omega-Liutex identification method.展开更多
The objective of this paper is to investigate the dynamic behavior of cloud cavitating flow around a flexible hydrofoil with experimental and numerical methods.The tightly coupled fluid-structure interaction(FSI)model...The objective of this paper is to investigate the dynamic behavior of cloud cavitating flow around a flexible hydrofoil with experimental and numerical methods.The tightly coupled fluid-structure interaction(FSI)modeling is applied and validated with the experimental data.The Q-criterion andω-criterion are applied to illustrate the interaction between the vortex structures and cavities.The flexibility is seen to result in nose-up twist deformation,causing a reduction of the shedding frequency from an increase in the attached cavity length.Due to the flexibility,the fluctuation of load coefficients of the flexible hydrofoil is larger than that of the rigid hydrofoil.Moreover,the re-entrant jet propagation speed of the flexible hydrofoil is greater than that of the rigid hydrofoil.The shed cloud cavity is observed to be uniform along the flexible hydrofoil span under the combined influence of the strong vibration and the gap flow.展开更多
Recently,the hydrodynamic noise is becoming a research hotspot because it not only affects the concealment and comfort of ships,but also affects the living condition of underwater mammals.Accurate prediction of hydrod...Recently,the hydrodynamic noise is becoming a research hotspot because it not only affects the concealment and comfort of ships,but also affects the living condition of underwater mammals.Accurate prediction of hydrodynamic noise requires that the detailed flow field has been simulated temporally and spatially with high fidelity method.In this paper,we introduce the current issues and challenges for the prediction of hydrodynamic noise,and provide an overview to several detailed flow field simulation methods which aim to resolve these issues.The overview could point the future directions for hydrodynamic noise prediction.展开更多
目的系统评价孕期牙周病与妊娠期糖尿病(gestational diabetes mellitus,GDM)发生风险的相关性。方法计算机检索PubMed、Web of Science、CBM、CNKI数据库,搜集有关牙周病和GDM的研究,检索时限均从建库至2021年10月23日。由2位评价员独...目的系统评价孕期牙周病与妊娠期糖尿病(gestational diabetes mellitus,GDM)发生风险的相关性。方法计算机检索PubMed、Web of Science、CBM、CNKI数据库,搜集有关牙周病和GDM的研究,检索时限均从建库至2021年10月23日。由2位评价员独立筛选文献、提取资料并评价纳入研究的偏倚风险后,采用RevMan 5.4软件进行Meta分析。结果共纳入11个研究,包括2910例孕妇。Meta分析结果显示:孕期患牙周病的孕妇发生GDM的风险是正常组孕妇的1.81倍[OR=1.81,95%CI(1.31,2.50),P=0.0003]。结论当前证据表明,孕期牙周病与GDM的发生风险存在正相关。受纳入研究数量和质量的限制,上述结论尚待更多高质量研究予以验证。展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.52131102.
文摘In this paper,we present an overview of numerical simulation methods for the flow around typical underwater vehicles at high Reynolds numbers,which highlights the dominant flow structures in different regions of interest.This overview covers the forebody,midbody,stern,wake region,and appendages and summarizes flow phenomena,including laminar-to-turbulent transition,turbulent boundary layers,flow under the influence of curvatures,wake interactions,and all associated complex vortex structures.Furthermore,the current issues and challenges of capturing these flow structures are addressed.This overview provides a deep insight into the use of numerical simulation methods,including the Reynolds-averaged Navier–Stokes(RANS)method,large eddy simulation(LES)method,and the hybrid RANS/LES method,and evaluates their applicability in capturing detailed flow features.
基金the Science and Technology Research Project of the Education Department of Jilin Province(No.JJKH20220862KJ)the Jilin Province higher education teaching reform research topic(No.20224BRFI7U003M)National Natural Science Foundation of China(No.82074324).
文摘Background:The aim of this study is to investigate the mechanism of action underlying the therapeutic effects of the national patent Chinese medicine compound“Qiangxinhuoli prescription(QXHLF)”on chronic heart failure(CHF).Methods:In vitro,the H 9 C 2 cell model was induced by ANGII,and cell proliferation and related protein expression were detected by Cell Counting Kit-8 and Western blot.In vivo,A rat model of CHF was prepared by ligation of the left anterior descending coronary artery.The effects of QXHLF on cardiac function in CHF rats were evaluated by cardiac index,hemodynamic changes,enzyme-linked immunosorbent assay,hematoxylin-eosin staining,immunohistochemistry,Western blot and RT-PCR.The expression of pro-apoptotic factors and anti-apoptotic factors,as well as TGFβ1,p-p38,TAK 1 mRNA,and protein,were detected.Results:In vitro,QXHLF has a significant inhibitory effect on the proliferation of H 9 C 2 cells.QXHLF can reduce the expression levels of TAK 1,TGFβ1,p-p38,Caspase3 and BAX proteins in H 9 C 2 cells,and increase the expression level of BCL 2 protein.In vivo,QXHLF has the potential to increase left ventricular systolic pressure,m aximum rate of change in left ventricular pressure while decreasing left ventricular end diastolic pressure,and inhibiting the serum levels of brain natriuretic peptide.Moreover,QXHLF exhibits significant improvements in the pathological alterations of myocardial cells and fibers in CHF rats,leading to enhanced myocardial tissue morphology and notable advantages in combating myocardial fibrosis.QXHLF can reduce the levels of BAX and Caspase3 and up-regulate the expression of BCL 2,thereby inhibiting cardiomyocyte apoptosis.Furthermore,QXHLF demonstrates inhibitory effects on the mRNA and protein expression levels of TGFβ1,TAK 1,and p-p38 in the heart tissue of the CHF rat model.Conclusion:These findings indicate that QXHLF has a therapeutic effect on CHF by inhibiting the p38-MAPK signaling pathway,reducing myocardial fibrosis,preventing apoptosis,inhibiting cell proliferation,and restoring myocardial injury.
基金National Natural Science Foundation of China(No.81374025)the Education Department of Jilin Province“13th Five-Year”science and technology research project.
基金Supported by Key Research and Development Program of Guangxi(Gui Ke AB18221095)Project of Famous Teacher Training Program in Youjiang Medical University for Nationalities-State Level Famous Teacher Training Program(You Yi Yuan Zi[2018]No.98)High-level Talent Scientific Research Project of Youjiang Medical University for Nationalities(01002018079).
文摘[Objectives]To study the anti-inflammatory and analgesic effects of Millettia speciosa and Tinpspora sinensis and their compatibility.[Methods](i)In the glacial acetic acid writhing experiment,60 SPF-grade Kunming mice were adopted,and the mice were randomly divided into 6 groups at male-female ratio of 1∶1,namely,the blank control group,M.speciosa group,T.sinensis group,M.speciosa compatible with T.sinensis group at the ratio of 1∶2(expressed as 1∶2 compatibility group),M.speciosa compatible with T.sinensis group at the ratio of 1∶1(expressed as 1∶1 compatibility group),and M.speciosa compatible with T.sinensis group at the ratio of 2∶1(expressed as 2∶1 compatibility group),12 mice for each group.Mice of the experimental groups were administered at a dose of 20 mL/kg,and the corresponding concentration of the Chinese medicine extract was given at 1 g/mL.The control group was administered with an equal volume of 0.9%physiological saline,and was intragastrically administered once every 24 h for 14 d.After intragastric administration for one hour on day 14,intraperitoneal injection of 0.5%glacial acetic acid solution was performed to induce pain.(ii)In the hot plate experiment,60 Kunming female SPF mice were adopted,grouped,intragastrically administered with the same glacial acetic acid writhing experiment for 14 d.After intragastric administration for one hour on day 14,the mice were placed on a hot plate apparatus at(55±0.5)℃.to measure the time of licking their hind feet.(iii)In the anti-inflammatory experiment,60 Kunming SPF mice were adopted,grouped,intragastrically administered with the same glacial acetic acid writhing experiment for 14 d.After intragastric administration for one hour on day 14,xylylene was administered to the left ears of mice at a dose of 50μL/piece to induce inflammation.[Results](i)In the glacial acetic acid writhing experiment,compared with the blank control group,the experimental group showed analgesic effects.Specifically,M.speciosa group,T.sinensis group,1∶2 compatibility group,1∶1 compatibility group,2∶1 compatibility group showed significant effect(P<0.05),the writhing inhibition rate was 17.65%,20.59%,29.41%,26.47%,and 44.12%,respectively,and 2∶1 compatibility group showed the most significant analgesic effects.(ii)In the hot plate experiment,compared with the control group,all experimental groups showed analgesic effect.Specifically,M.speciosa group,T.sinensis group,1∶2 compatibility group,1∶1 compatibility group,2∶1 compatibility group showed significant effect(P<0.05),the pain threshold improvement rates were 16.13%,14.55%,14.96%,29.95%,and 58.68%,respectively,and 2∶1 compatibility group showed the most significant analgesic effect.(iii)In the anti-inflammatory experiment,the swelling degree of the 1∶2 compatibility group was significantly different from that of the blank control group,M.speciosa group,T.sinensis group(P<0.05).and 1∶2 compatibility group showed the most significant anti-inflammatory effect.[Conclusions]M.speciosa,T.sinensis,and their compatibility had anti-inflammatory and analgesic effects.The 2∶1 compatibility group had the best analgesic effects,and 1∶2 compatibility group had the best anti-inflammatory effects.
基金supported by the National Natural Science Foundation of China(Grant No.52131102)the National Key Research and Development Program of China(Grant Nos.2022YFC2806705,2019YFB1704200).
文摘This paper presents a numerical investigation of the interaction among wave,flow and a fixed cylinder using the naoe-FOAM-SJTU solver,which is a viscous solver for hydrodynamics based on OpenFOAM.The simulation considers the strong nonlinear interaction among a regular wave,flow,and a single fixed cylinder due to viscosity,which is common in offshore structures.The study focus on the vortex induced by viscosity and its significant role in hydrodynamic performance computation.A mesh convergence study is conducted prior to the simulation,and a proper set of mesh is chosen.The simultaneous generation of the regular wave and flow is realized using the numerical field boundary,and the wave propagation is validated.The results of wave elevation and pressures captured by wave gauges and probes around the fixed cylinder are compared with experiment results.The structure of vortices is displayed at significant times,and the phenomena of wave elevation and pressure changes around the cylinder are analyzed in detail using the Omega-Liutex identification method.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52279081,51839001)supported by the Natural Science Foundation of Beijing Municipality(Grant No.3232033)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.2023CX01004)the BIT Research and Innovation Promoting Project(Grant No.2022YCXY014).
文摘The objective of this paper is to investigate the dynamic behavior of cloud cavitating flow around a flexible hydrofoil with experimental and numerical methods.The tightly coupled fluid-structure interaction(FSI)modeling is applied and validated with the experimental data.The Q-criterion andω-criterion are applied to illustrate the interaction between the vortex structures and cavities.The flexibility is seen to result in nose-up twist deformation,causing a reduction of the shedding frequency from an increase in the attached cavity length.Due to the flexibility,the fluctuation of load coefficients of the flexible hydrofoil is larger than that of the rigid hydrofoil.Moreover,the re-entrant jet propagation speed of the flexible hydrofoil is greater than that of the rigid hydrofoil.The shed cloud cavity is observed to be uniform along the flexible hydrofoil span under the combined influence of the strong vibration and the gap flow.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51909160,52131102)the National Key Research and Development Program of China(2022YFC2806705,2019YFB1704200).
文摘Recently,the hydrodynamic noise is becoming a research hotspot because it not only affects the concealment and comfort of ships,but also affects the living condition of underwater mammals.Accurate prediction of hydrodynamic noise requires that the detailed flow field has been simulated temporally and spatially with high fidelity method.In this paper,we introduce the current issues and challenges for the prediction of hydrodynamic noise,and provide an overview to several detailed flow field simulation methods which aim to resolve these issues.The overview could point the future directions for hydrodynamic noise prediction.
