Disinfection of swimming pool water is critical to ensure the safety of the recreational activity for swimmers.However,swimming pools have a constant loading of organic matter from input water and anthropogenic contam...Disinfection of swimming pool water is critical to ensure the safety of the recreational activity for swimmers.However,swimming pools have a constant loading of organic matter from input water and anthropogenic contamination,leading to elevated levels of disinfection byproducts(DBPs).Epidemiological studies have associated increased risks of adverse health effects with frequent exposure to DBPs in swimming pools.Zhang et al.(2023b)investigated the occurrence of trihalomethanes(THMs),haloacetic acids(HAAs),haloacetonitriles(HANs),and haloacetaldehydes(HALs)in eight swimming pools and the corresponding input water in a city in Eastern China.The concentrations of THMs,HAAs,HANs,and HALs in swimming poolswere 1–2 orders of magnitude higher than those detected in the input water.The total lifetime cancer and non-cancer health risks of swimmers through oral,dermal,inhalation,buccal,and aural exposure pathways were assessed using the United States Environmental Protection Agency’s(USEPA)standard model and Swimmer Exposure Assessment Model(SWIMODEL).The results showed that dermal and inhalation pathways were the most significant for the associated cancer and non-cancer risks.This article provides an overview and perspectives of DBPs in swimming pools,the benefits of swimming,the need to improve the monitoring of DBPs,and the importance of swimmers’hygiene practices to keep swimming pools clean.The benefits of swimming outweigh the risks from DBP exposure for the promotion of public health.展开更多
Fish swimming hydrodynamics serves as a critical foundation for aquatic ecological conservation,with recent research extending from 2D to 3D perspectives.This study employs 3D high-fidelity modeling with dynamic mesh ...Fish swimming hydrodynamics serves as a critical foundation for aquatic ecological conservation,with recent research extending from 2D to 3D perspectives.This study employs 3D high-fidelity modeling with dynamic mesh technology to investigate how cylindrical obstacles at varying positions affect Carassius auratus locomotion.Analysis of nine configurations reveals bidirectional flow interactions between fish and cylinders,with cylinder wake influence persisting at 1-2 times the total length intervals but diminishing at 3times.Compared with swimming in uniform flow,the mechanical benefit of C.auratus located 2 times the total length directly behind the cylinder is the largest,and its value reaches 4.19 times.Wavelet analysis of 30-cycle mechanical data demonstrates closer intervals enhance benefit magnitude,whereas greater distances accelerate benefit realization.These 3D computational findings corroborate 2D studies while providing new spatial interaction insights,offering theoretical foundations for fish conservation strategies related to hydraulic structures.展开更多
Deep-sea aquaculture is an emerging trend due to the contamination and overexploitation of nearshore mariculture areas.However,the complex water conditions in the deep sea impose higher demands on the swimming perform...Deep-sea aquaculture is an emerging trend due to the contamination and overexploitation of nearshore mariculture areas.However,the complex water conditions in the deep sea impose higher demands on the swimming performance of farmed animals.Spotted sea bass(Lateolabrax maculatus)is one of the most economically important fish species in China.To investigate the mechanisms underlying the individual variations in swimming performance among spotted sea bass,we measured their critical swimming speed(U_(crit))and morphological phenotypes.Total length,body length,body weight,caudal region length,and condition factor showed significant positive correlations with absolute Ucrit.In contrast,caudal fin length and pectoral fin length tended to hinder the swimming performance of individual spotted sea bass.Additionally,white muscle tissues from fish exhibiting good swimming performance(relative U_(crit)>8.20 BL/s)and poor swimming performance(relative U_(crit)<7.31 BL/s)were sampled for RNA-seq.A total of 694 differential expression genes(DEGs)were identified through gene expression analysis,with significant enrichment in GO terms such as mitochondrial protein complex,ribosomal subunit,structural constituent of ribosome,and oxidative phosphorylation,as well as genes in KEGG pathways including ribosome and metabolic pathways.In conclusion,our study for the first time comprehensively elucidated the impact of morphology of spotted sea bass on its individual differences in swimming ability,and analyzed the genetic basis underlying swimming ability using transcriptomic methods.This study provides a theoretical basis for the potential breeding varieties of spotted sea bass suitable for deep-sea aquaculture.展开更多
The role of hydrodynamic effect in the meeting of multiple fish is a fascinating topic.The interactions of two self-propelled flexi-ble plates swimming in opposite directions horizontally and maintaining a certain lat...The role of hydrodynamic effect in the meeting of multiple fish is a fascinating topic.The interactions of two self-propelled flexi-ble plates swimming in opposite directions horizontally and maintaining a certain lateral distance are numerically simulated using a penalty-immersed boundary method.The effects of the flapping phase and lateral distance on the propulsive performance of two fish meetings are analyzed.Results show that,when two plates meet,if their leading edges diverge laterally,the individual plate can efficiently and rapidly move apart from the other horizontally.If their leading edges converge laterally,the plate motion can be retarded,leading to high energy consumption.Moreover,an increasing lateral distance between two plates significantly weakens the fluid-structure interactions,resulting in an exponential decline in mean cruising speed.A quantitative force analysis based on vortex dynamic theory is performed to gain physics insight into the hydrodynamic interaction mechanism.It is found that lateral separation between the two leading edges enhances the vorticity generation and boundary vorticity flux on the surface of the plate,subsequently reinforcing the thrust effect and increasing horizontal velocity.This study offers insight into the hydro-dynamic mechanisms of the fluid-structure interactions among fish moving toward each other and suggests potential strategies for enhancing the maneuverability of robotic fish in complex environment.展开更多
Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- a...Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- and three-dimensional moving boundary problem, which combines the adaptive multi-grid finite volume method and the methods of immersed boundary and volume of fluid, it is found that due to the interactions of vortices in the wakes, without proper control, a fish school swim with a given flap- ping rule can not keep the fixed shape of a queue. In order to understand the secret of fish swimming, a new feedback con- trol strategy of fish motion is proposed for the first time, i,e., the locomotion speed is adjusted by the flapping frequency of the caudal, and the direction of swimming is controlled by the swinging of the head of a fish. Results show that with this feedback control strategy, a fish school can keep the good order of a queue in cruising, turning or swimming around circles. This new control strategy, which separates the speed control and direction control, is important in the construction of biomimetic robot fish, with which it greatly simplifies the control devices of a biomimetic robot fish.展开更多
目的总结颅内支撑导管辅助Solitaire支架取栓+吸栓技术(Solitaire FR with intracranial support catheter for mechanical thrombectimy,SWIM)治疗大血管闭塞性脑梗死的围手术期护理要点。方法对80例急性大血管闭塞性脑梗死患者采用SWI...目的总结颅内支撑导管辅助Solitaire支架取栓+吸栓技术(Solitaire FR with intracranial support catheter for mechanical thrombectimy,SWIM)治疗大血管闭塞性脑梗死的围手术期护理要点。方法对80例急性大血管闭塞性脑梗死患者采用SWIM技术进行取栓和吸栓相结合开通血管,加强围手术期护理管理。结果 80例患者中,75例血管成功再通,5例血管再通不佳,术中医护配合良好。结论快速有效地完善术前准备、密切观察病情、熟练的术中护理配合、仔细认真的术后护理有利于血管再通治疗顺利完成,改善患者预后。展开更多
Fish have a remarkable amount of variation in their swimming performance, from within species dif- ferences to diversity among major taxonomic groups. Fish swimming is a complex, integrative phenotype and has the abil...Fish have a remarkable amount of variation in their swimming performance, from within species dif- ferences to diversity among major taxonomic groups. Fish swimming is a complex, integrative phenotype and has the ability to plastically respond to a myriad of environmental changes. The plasticity of fish swimming has been observed on whole-organismal traits such as burst speed or critical swimming speed, as well as underlying phenotypes such as muscle fiber types, kinematics, cardiovascular system, and neuronal processes. Whether the plastic responses of fish swimming are beneficial seems to depend on the environmental variable that is changing. For example, because of the effects of temperature on biochemical processes, alterations of fish swimming in response to tem- perature do not seem to be beneficial. In contrast, changes in fish swimming in response to variation in flow may benefit the fish to maintain position in the water column. In this paper, we examine how this plasticity in fish swimming might evolve, focusing on environmental variables that have received the most attention： temperature, habitat, dissolved oxygen, and carbon dioxide variation. Using examples from previous research, we highlight many of the ways fish swimming can plastic- ally respond to environmental variation and discuss potential avenues of future research aimed at understanding how plasticity of fish swimming might evolve. We consider the direct and indirect ef- fects of environmental variation on swimming performance, including changes in swimming kine- matics and suborganismal traits thought to predict swimming performance. We also discuss the role of the evolution of plasticity in shaping macroevolutionary patterns of diversity in fish swimming.展开更多
The three-dimensional lattice Boltzmann method(LBM)is used to simulate the motion of a spherical squirmer in a square tube,and the steady motion velocity of a squirmer with different Reynolds numbers(Re,ranging from 0...The three-dimensional lattice Boltzmann method(LBM)is used to simulate the motion of a spherical squirmer in a square tube,and the steady motion velocity of a squirmer with different Reynolds numbers(Re,ranging from 0.1 to 2)and swimming types is investigated and analyzed to better understand the swimming characteristics of microorganisms in different environments.First,as the Reynolds number increases,the effect of the inertial forces becomes significant,disrupting the squirmer's ability to maintain its theoretical velocity.Specifically,as the Reynolds number increases,the structure of the flow field around the squirmer changes,affecting its velocity of motion.Notably,the swimming velocity of the squirmer exhibits a quadratic relationship with the type of swimming and the Reynolds number.Second,the narrow tube exerts a significant inhibitory effect on the squirmer motion.In addition,although chirality does not directly affect the swimming velocity of the squirmer,it can indirectly affect the velocity by changing its motion mode.展开更多
文摘Disinfection of swimming pool water is critical to ensure the safety of the recreational activity for swimmers.However,swimming pools have a constant loading of organic matter from input water and anthropogenic contamination,leading to elevated levels of disinfection byproducts(DBPs).Epidemiological studies have associated increased risks of adverse health effects with frequent exposure to DBPs in swimming pools.Zhang et al.(2023b)investigated the occurrence of trihalomethanes(THMs),haloacetic acids(HAAs),haloacetonitriles(HANs),and haloacetaldehydes(HALs)in eight swimming pools and the corresponding input water in a city in Eastern China.The concentrations of THMs,HAAs,HANs,and HALs in swimming poolswere 1–2 orders of magnitude higher than those detected in the input water.The total lifetime cancer and non-cancer health risks of swimmers through oral,dermal,inhalation,buccal,and aural exposure pathways were assessed using the United States Environmental Protection Agency’s(USEPA)standard model and Swimmer Exposure Assessment Model(SWIMODEL).The results showed that dermal and inhalation pathways were the most significant for the associated cancer and non-cancer risks.This article provides an overview and perspectives of DBPs in swimming pools,the benefits of swimming,the need to improve the monitoring of DBPs,and the importance of swimmers’hygiene practices to keep swimming pools clean.The benefits of swimming outweigh the risks from DBP exposure for the promotion of public health.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFC3204202National Natural Science Foundation of China,Grant/Award Number:52122904Ministry of Water Resources,Grant/Award Number:SKS-2022121。
文摘Fish swimming hydrodynamics serves as a critical foundation for aquatic ecological conservation,with recent research extending from 2D to 3D perspectives.This study employs 3D high-fidelity modeling with dynamic mesh technology to investigate how cylindrical obstacles at varying positions affect Carassius auratus locomotion.Analysis of nine configurations reveals bidirectional flow interactions between fish and cylinders,with cylinder wake influence persisting at 1-2 times the total length intervals but diminishing at 3times.Compared with swimming in uniform flow,the mechanical benefit of C.auratus located 2 times the total length directly behind the cylinder is the largest,and its value reaches 4.19 times.Wavelet analysis of 30-cycle mechanical data demonstrates closer intervals enhance benefit magnitude,whereas greater distances accelerate benefit realization.These 3D computational findings corroborate 2D studies while providing new spatial interaction insights,offering theoretical foundations for fish conservation strategies related to hydraulic structures.
基金National Key R&D Program of China(No.2022YFD2400103).
文摘Deep-sea aquaculture is an emerging trend due to the contamination and overexploitation of nearshore mariculture areas.However,the complex water conditions in the deep sea impose higher demands on the swimming performance of farmed animals.Spotted sea bass(Lateolabrax maculatus)is one of the most economically important fish species in China.To investigate the mechanisms underlying the individual variations in swimming performance among spotted sea bass,we measured their critical swimming speed(U_(crit))and morphological phenotypes.Total length,body length,body weight,caudal region length,and condition factor showed significant positive correlations with absolute Ucrit.In contrast,caudal fin length and pectoral fin length tended to hinder the swimming performance of individual spotted sea bass.Additionally,white muscle tissues from fish exhibiting good swimming performance(relative U_(crit)>8.20 BL/s)and poor swimming performance(relative U_(crit)<7.31 BL/s)were sampled for RNA-seq.A total of 694 differential expression genes(DEGs)were identified through gene expression analysis,with significant enrichment in GO terms such as mitochondrial protein complex,ribosomal subunit,structural constituent of ribosome,and oxidative phosphorylation,as well as genes in KEGG pathways including ribosome and metabolic pathways.In conclusion,our study for the first time comprehensively elucidated the impact of morphology of spotted sea bass on its individual differences in swimming ability,and analyzed the genetic basis underlying swimming ability using transcriptomic methods.This study provides a theoretical basis for the potential breeding varieties of spotted sea bass suitable for deep-sea aquaculture.
基金joined PI of Westlake University(Grant Nos.041030150118 and 103110556022101)Scientific Research Funding Project of Westlake University(Grant No.2021WUFP017).
文摘The role of hydrodynamic effect in the meeting of multiple fish is a fascinating topic.The interactions of two self-propelled flexi-ble plates swimming in opposite directions horizontally and maintaining a certain lateral distance are numerically simulated using a penalty-immersed boundary method.The effects of the flapping phase and lateral distance on the propulsive performance of two fish meetings are analyzed.Results show that,when two plates meet,if their leading edges diverge laterally,the individual plate can efficiently and rapidly move apart from the other horizontally.If their leading edges converge laterally,the plate motion can be retarded,leading to high energy consumption.Moreover,an increasing lateral distance between two plates significantly weakens the fluid-structure interactions,resulting in an exponential decline in mean cruising speed.A quantitative force analysis based on vortex dynamic theory is performed to gain physics insight into the hydrodynamic interaction mechanism.It is found that lateral separation between the two leading edges enhances the vorticity generation and boundary vorticity flux on the surface of the plate,subsequently reinforcing the thrust effect and increasing horizontal velocity.This study offers insight into the hydro-dynamic mechanisms of the fluid-structure interactions among fish moving toward each other and suggests potential strategies for enhancing the maneuverability of robotic fish in complex environment.
基金supported by the National Natural Science Foundation of China(10172095 and 10672183)
文摘Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- and three-dimensional moving boundary problem, which combines the adaptive multi-grid finite volume method and the methods of immersed boundary and volume of fluid, it is found that due to the interactions of vortices in the wakes, without proper control, a fish school swim with a given flap- ping rule can not keep the fixed shape of a queue. In order to understand the secret of fish swimming, a new feedback con- trol strategy of fish motion is proposed for the first time, i,e., the locomotion speed is adjusted by the flapping frequency of the caudal, and the direction of swimming is controlled by the swinging of the head of a fish. Results show that with this feedback control strategy, a fish school can keep the good order of a queue in cruising, turning or swimming around circles. This new control strategy, which separates the speed control and direction control, is important in the construction of biomimetic robot fish, with which it greatly simplifies the control devices of a biomimetic robot fish.
文摘目的总结颅内支撑导管辅助Solitaire支架取栓+吸栓技术(Solitaire FR with intracranial support catheter for mechanical thrombectimy,SWIM)治疗大血管闭塞性脑梗死的围手术期护理要点。方法对80例急性大血管闭塞性脑梗死患者采用SWIM技术进行取栓和吸栓相结合开通血管,加强围手术期护理管理。结果 80例患者中,75例血管成功再通,5例血管再通不佳,术中医护配合良好。结论快速有效地完善术前准备、密切观察病情、熟练的术中护理配合、仔细认真的术后护理有利于血管再通治疗顺利完成,改善患者预后。
文摘Fish have a remarkable amount of variation in their swimming performance, from within species dif- ferences to diversity among major taxonomic groups. Fish swimming is a complex, integrative phenotype and has the ability to plastically respond to a myriad of environmental changes. The plasticity of fish swimming has been observed on whole-organismal traits such as burst speed or critical swimming speed, as well as underlying phenotypes such as muscle fiber types, kinematics, cardiovascular system, and neuronal processes. Whether the plastic responses of fish swimming are beneficial seems to depend on the environmental variable that is changing. For example, because of the effects of temperature on biochemical processes, alterations of fish swimming in response to tem- perature do not seem to be beneficial. In contrast, changes in fish swimming in response to variation in flow may benefit the fish to maintain position in the water column. In this paper, we examine how this plasticity in fish swimming might evolve, focusing on environmental variables that have received the most attention： temperature, habitat, dissolved oxygen, and carbon dioxide variation. Using examples from previous research, we highlight many of the ways fish swimming can plastic- ally respond to environmental variation and discuss potential avenues of future research aimed at understanding how plasticity of fish swimming might evolve. We consider the direct and indirect ef- fects of environmental variation on swimming performance, including changes in swimming kine- matics and suborganismal traits thought to predict swimming performance. We also discuss the role of the evolution of plasticity in shaping macroevolutionary patterns of diversity in fish swimming.
基金Project supported by the National Natural Science Foundation of China(Nos.12132015 and 12372251)the Fundamental Research Funds for the Provincial Universities of Zhejiang of China(No.2023YW69)。
文摘The three-dimensional lattice Boltzmann method(LBM)is used to simulate the motion of a spherical squirmer in a square tube,and the steady motion velocity of a squirmer with different Reynolds numbers(Re,ranging from 0.1 to 2)and swimming types is investigated and analyzed to better understand the swimming characteristics of microorganisms in different environments.First,as the Reynolds number increases,the effect of the inertial forces becomes significant,disrupting the squirmer's ability to maintain its theoretical velocity.Specifically,as the Reynolds number increases,the structure of the flow field around the squirmer changes,affecting its velocity of motion.Notably,the swimming velocity of the squirmer exhibits a quadratic relationship with the type of swimming and the Reynolds number.Second,the narrow tube exerts a significant inhibitory effect on the squirmer motion.In addition,although chirality does not directly affect the swimming velocity of the squirmer,it can indirectly affect the velocity by changing its motion mode.
