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
I.请根据录音,填写单词或把单词补充完整。II.听对话,选择正确的答案。1.What is Emily’s favorite animal?A.Dolphins.B.Lions.C.Elephants.D.Tigers.2.How fast can dolphins swim?A.10 miles per hour.B.20 miles per hour.C.30 mil...I.请根据录音,填写单词或把单词补充完整。II.听对话,选择正确的答案。1.What is Emily’s favorite animal?A.Dolphins.B.Lions.C.Elephants.D.Tigers.2.How fast can dolphins swim?A.10 miles per hour.B.20 miles per hour.C.30 miles per hour.D.40 miles per hour.展开更多
Summer is my favorite season of the year.The weather is hot,but I don’t mind because there are so many fun things to do.In summer,I can swim in the pool with my friends.The cool water makes me feel really comfortable.
Tachypleus tridentatus,a critical biological resource used in Limulus Amebocyte Lysate(LAL),has experienced a sharp decline that is attracting global attention.Although artificial husbandry and breeding are promising ...Tachypleus tridentatus,a critical biological resource used in Limulus Amebocyte Lysate(LAL),has experienced a sharp decline that is attracting global attention.Although artificial husbandry and breeding are promising strategies for promoting the proliferation of T.tridentatus,technological research is still in its infancy.Studying the behavioral characteristics during the reproductive period is crucial for identifying the environmental requirements of T.tridentatus.In this study,the behaviors of adult T.tridentatus were recorded continuously in an artificial aquaculture environment using underwater cameras.The behavior of adult T.tridentatus is mainly characterized by locomotion,feeding,and reproduction,which encompass a total of 11 types of behavior.The types of locomotion,including respiratory,swimming,climbing,and turning over,were coordinated with each other.Particularly,specific swimming patterns were utilized to efficiently conserve energy.Tachypleus tridentatus effectively utilized coordinated movements of its appendages to assist in feeding.This multi-organ coordinated feeding strategy allowed them to move quickly or avoid threats,thereby preventing food from being taken by others.The coordinated feeding pattern involving multiple organs enhances efficiency during rapid movement or evasion,protecting the food from being contested by other organisms.Competitive courtship and a monogamous mating strategy allowed T.tridentatus to efficiently find mates and lay eggs in suitable environments.Repeated spawning behaviors contributed to the high reproductive success rate.This study elucidated the ecological requirements of T.tridentatus from a behavioral perspective,thereby providing valuable references for implementing and optimizing its rearing environment.展开更多
Underwater jet propulsion bio-inspired robots have typically been designed based on soft-bodied organisms, exhibiting relatively limited forms of locomotion. Scallop, a bivalve organism capable of jet propulsion, hold...Underwater jet propulsion bio-inspired robots have typically been designed based on soft-bodied organisms, exhibiting relatively limited forms of locomotion. Scallop, a bivalve organism capable of jet propulsion, holds significant importance in the study of underwater motion mechanisms. In this study, we present theoretical fluid mechanics analysis and modeling of the three distinct motion stages of scallops, providing parameterized descriptions of scallop locomotion mechanisms. Accordingly, three-stage adaptive motion control for the scallop robot and model-based robot configuration optimization design were achieved. An experimental platform and a robot prototype were built to validate the accuracy of the motion model and the effectiveness of the control strategy. Additionally, based on the models, future optimization directions for the robot are proposed.展开更多
Captive breeding and stocking are commonly employed strategies for enhancing fisheries and conserving endangered fish species.However,hatchery-raised fish often exhibit reduced performance in the wild,displaying alter...Captive breeding and stocking are commonly employed strategies for enhancing fisheries and conserving endangered fish species.However,hatchery-raised fish often exhibit reduced performance in the wild,displaying alterations in physiological,morphological,and behavioral traits.We tested for differences in swimming capacity and metabolic traits between wild and hatchery-reared individuals of the Spanish toothcarp(Aphanius iberus)from 2 different populations.Furthermore,we experimentally tested if these changes translated into fitness differences after their stocking into the wild.There were significant differences in swimming capacity and metabolic traits between wild and hatchery-reared individuals and also between the 2 populations.Captive-bred individuals displayed consistently lower metabolic rates than wild individuals from the same population(30-76% lower).Critical swimming speed rather differed between the 2 populations.Sex-specific differences were observed in maximum and standard metabolic rates,with wild individuals and females generally exhibiting higher values but with some exceptions.During a 3-month experiment,survival rates did not significantly differ between wild and captive-bred fish.Captive-bred individuals started smaller but exhibited rapid growth during the experiment.Initially,larger captive-bred fish had lower body conditions than their wild counterparts,but these differences progressively diminished.In summary,captive-bred individuals of this fish species showed lower metabolic rates,although the differences with wild individuals slightly depended on sex and size.展开更多
Locomotion is thermally sensitive in ectotherms and therefore it is typically expressed differently among thermally heterogenous environments.Locomotion is a complex function,and whereas physiological and behavioral t...Locomotion is thermally sensitive in ectotherms and therefore it is typically expressed differently among thermally heterogenous environments.Locomotion is a complex function,and whereas physiological and behavioral traits that infuence locomotor performance may respond to thermal variation throughout life,other contributing traits,like body shape,may have more restricted responses.How morphology affects locomotorperformance under variable temperature conditions is unknown.Here,we investigated 3 genetically distinct strains of zebrafsh,Danio rerio(AB,WIK,and Tu)with a shared multi-generational history at 28℃.After rearing fsh at 28℃,we measured prolonged swimming speed(Ucrit)at each of 6 temperatures(between 16℃ and 34℃).Speed was strongly positively correlated among temperatures,resulting in most amongindividual variation being temperature-independent(i.e.,fsh were relatively fast or slow across all temperatures).However,we also detectedsignifcant variation along 2 axes refecting temperature-dependent variation.Although strains differed in mean swimming performance,withinstrain(among-individual)patterns of speed variation were markedly consistent.Body shape and size explained signifcant variation amongindividuals in both temperature-independent and temperature-dependent axes of swimming speed variation.Notably,morphological traits thatwere most strongly associated with temperature-independent performance variation(i.e.,faster-slower)differed from those associated withtemperature-dependent(i.e.,hotter-colder)variation.Further,there were signifcant differences among strains in both the direction and strengthof association for specifc morphological traits.Our results suggest that thermally heterogenous environments could have complex effects onthe evolution of traits that contribute to whole organism performance traits.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
In the mysterious depths of the ocean,robots glide between reefs and corals,avoid obstacles,navigate independently,and fulfil their tasks as if they had a vision that could penetrate the murkiness of the water.The Chi...In the mysterious depths of the ocean,robots glide between reefs and corals,avoid obstacles,navigate independently,and fulfil their tasks as if they had a vision that could penetrate the murkiness of the water.The Chinese company Chasing has developed a robot capable of diving to a depth of 350 metres.As an underwater photographer,lifeguard or swimming pool cleaner,it demonstrates the expertise the company has acquired over years of research and development work.展开更多
Swimming crab(Portunus trituberculatus)eggs contain abundant phospholipids and polyunsaturated fatty acids with specific bioactivities.However,more studies on the functions of other nutrients are needed.Here,a novel s...Swimming crab(Portunus trituberculatus)eggs contain abundant phospholipids and polyunsaturated fatty acids with specific bioactivities.However,more studies on the functions of other nutrients are needed.Here,a novel sialoglycopeptide from P.trituberculatus eggs,which was termed as Pt-SGP,was isolated with enzymolysis.Pt-SGP was a 6480-Da pure sialoglycopeptide.O-glycan units existed between peptides and sugars.Pt-SGP was composed of 10.69%protein,71.43%hexose,and 11.27%Neu5Gc acid.Analyzed with HPLC,GC-MS,and NMR spectrometry,the carbohydrate chain of Pt-SGP was{(4GlcNAc1-2Man1-3)/(4GlcNAc1-2Man1-6)Man1-6}/{4Glc1-4}Glc1-4Glc1-3GlcNAc1.The MS spectrometry analysis result showed that the peptide chain was Val-Ala-Thr*-Val-Ser*-Leu-Pro-Arg.The results on mice showed Pt-SGP could reduce body weight gain by 18.13%,white adipose weight by 28.57%,serum TC by 22.32,serum TG by 9.46%,serum LDL-C by 27.69%,hepatic TC by 73.21%,and hepatic TG by 25.20%.Furthernore,it could increase serum HDL-C by 75.96%,mitigate adipocyte size and hepatic lipid accumulation in high fat diet-fed mice.Pt-SGP significantly down-regulated C/EBPαsignaling and up-regulated AMPKαsignaling in the epididymal fat tissues.The findings indicate that Pt-SGP exhibits notable anti-obesity properties,and can potentially become a promising dietary supplement for anti-obesity.展开更多
The cutaneous ridges on dolphin skin have long been believed to effectively reduce friction drag, thereby contributing to overall drag reduction. However, since these skin ridges are oriented perpendicular to the swim...The cutaneous ridges on dolphin skin have long been believed to effectively reduce friction drag, thereby contributing to overall drag reduction. However, since these skin ridges are oriented perpendicular to the swimming direction, they also generate additional pressure drag, raising questions about the impact of the shape-induced pressure forces on swimming. Inspired by the microvibrations observed on dolphin skin, we hypothesize that the microstructure on dolphin skin is not static but dynamically oscillates in the form of Longitudinal Micro-Ultrasonic Waves (LMUWs). To explore this, we carried out a series of Computational Fluid Dynamics (CFD) simulations based on Large Eddy Simulation (LES) model to investigate the impact of pressure drag on the total drag acting on an oscillating skin surface under realistic turbulent flow conditions. The results indicate that the dynamic skin oscillations induce a new dynamic Stokes boundary layer, which has the potential to convert pressure drag into a negative force, thereby reducing total drag under the influence of traveling LMUW excitations. Furthermore, a relative velocity ξ, defined as the difference between the wave speed c and the external flow speed U, is introduced to evaluate the drag-reduction effect dominated by pressure. The findings reveal that pressure drag remains negative when ξ > 0. As ξ increases, the thrust effect induced by negative pressure becomes increasingly significant, ultimately counteracting friction drag and eliminating total drag. This pressure-dominated drag reduction mechanism thus demonstrates a novel strategy for the drag reduction technology and the potential of unveiling the mysteries behind dolphin swimming.展开更多
The early life stages of marine organisms are pivotal in shaping community dynamics and resource availability.In this study,we focused on Portunus trituberculatus,a crustacean integral to China's fisheries economy...The early life stages of marine organisms are pivotal in shaping community dynamics and resource availability.In this study,we focused on Portunus trituberculatus,a crustacean integral to China's fisheries economy,and examined the effect of sea surface temperature(SST)in its critical early life stages on subsequent yields.To analyze the correlation between SST in different larval stages and the corresponding yield of P.trituberculatus,we simulated the transport and distribution of larvae from 2014 to 2022 by employing circulation models and Lagrangian particle tracking experiments(LPTE).In the five years(2014,2015,2016,2019,and 2020),particles were transported in a northwestern direction and moved in the direction of low SST.The distribution of particles in the megalopa stage(M stage)were located in the region of the lower temperature.In 2017,2018,and 2021,the particles were transported in a northeastern direction but they did not move with the gradient of low SST in these years,and the particles in the last M stage were located in the region where the SST was at the peak of the time period.In 2022,the distribution was observed for most of the particles in the southwestern part of Zhejiang coast,a small part of them were transported in the northwestern direction and a small amount of particles was distributed offshore along the northern area of the Zhejiang coast.The correlations between the SST at each stage of larvae with the corresponding year's yield showed that the yield of P.trituberculatus decreased significantly(R=-0.772,P=0.015)with increasing SST at the M stage.This study preliminarily explains the correlation between SST at the larval stage and the yield of P.trituberculatus and provides essential information for scientific stock enhancement in the future.展开更多
Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pat...Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pathogenesis.One of the major reasons is the restricted availability of validated animal models due to the absence of consensus on the pathology and etiology of depression.Besides,some core symptoms such as depressed mood,feeling of worthlessness,and recurring thoughts of death or suicide,are impossible to be modeled on laboratory animals.Currently,the criteria for identifying animal models of depression rely on either of the 2 principles：actions of known antidepressants and responses to stress.This review mainly focuses on the most widely used animal models of depression,including learned helplessness,chronic mild stress,and social defeat paradigms.Also,the behavioral tests for screening antidepressants,such as forced swimming test and tail suspension test,are also discussed.The advantages and major drawbacks of each model are evaluated.In prospective,new techniques that will be beneficial for developing novel animal models or detecting depression are discussed.展开更多
Objective Striatum may be involved in depressive disorders according to the neuroimaging analysis and clinical data. However, no animal model at present supported the possible role of striatum in the pathogenesis of d...Objective Striatum may be involved in depressive disorders according to the neuroimaging analysis and clinical data. However, no animal model at present supported the possible role of striatum in the pathogenesis of depression. In the present study, we have investigated the depressive-like behavior in mice recently intoxicated with 3-nitropropionic acid （3- NP）, a widely known toxin that selectively damages the striatum in the brain. Methods Mouse model was made with subacute systemic 3-NP treatment, and the depressive-like behavior was measured using the duration of immobility during forced swimming test （FST）. Results When the mice at day 15 post-intoxication just totally recovered from motor deficits, the duration of immobility in FST was significantly longer than that in controls. The depressive-like behavior was not due to the fatigue or general sickness following 3-NP intoxication and could be reversed by the antidepressant, desipramine hydrochloride. In two successive FST in 24 h interval, the depressive-like behavior could be observed again in subsequent FST （at day 16 post-intoxication）, and the mice presented a normal ＂learned helplessness＂. Conclusion A novel depression animal model could be established in mice during the initial period of recovery from 3-NP intoxication. The depression-like behavior might occur independently without involvement of cognitive defects, and the striatal lesions may underlie the depression-like behavior attributable to 3-NP intoxication.展开更多
We investigated the concentration of trihalomethanes （THMs） in tap water and swimming pool water in the area of the Nakhon Path- om Municipality during the period April 2005-March 2006. The concentrations of total T...We investigated the concentration of trihalomethanes （THMs） in tap water and swimming pool water in the area of the Nakhon Path- om Municipality during the period April 2005-March 2006. The concentrations of total THMs, chloroform, bromodichloromethane, dibromochloromethane and bromoform in tap water were 12.70-41.74, 6.72-29.19, 1.12-11.75, 0.63-3.55 and 0.08-3.40 μg/L, respectively, whereas those in swimming pool water were 26.15-65.09, 9.50-36.97, 8.90-18.01, 5.19-22.78 and ND-6.56 μg/L, respectively. It implied that the concentration of THMs in swimming pool water was higher than those in tap water, particularly, brominated-THMs. Both tap water and swimming pool water contained concentrations of total THMs below the standards of the World Health Organization （WHO）, European Union （EU） and the United States Environmental Protection Agency （USEPA） phase Ⅰ, but 1 out of 60 tap water samples and 60 out of 72 swimming pool water samples contained those over the Standard of the USEPA phase Ⅱ. From the two cases of cancer risk assessment including Case Ⅰ Non-Swimmer and Case Ⅱ Swimmer, assessment of cancer risk of nonswimmers from exposure to THMs at the highest and the average concentrations was 4.43×10^-5 and 2.19×10^-5, respectively, which can be classified as acceptable risk according to the Standard of USEPA. Assessment of cancer risk of swimmers from exposure to THMs at the highest and the average concentrations was 1.47×10^-3 and 7.99×10^-4, respectively, which can be classified as unacceptable risk and needs to be improved. Risk of THMs exposure from swimming was 93.9%-94.2% of the total risk. Cancer risk of THMs concluded from various routes in descending order was： skin exposure while swimming, gastro-intestinal exposure from tap water intake, and skin exposure to tap water and gastro-intestinal exposure while swimming. Cancer risk from skin exposure while swimming was 94.18% of the total cancer risk.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.
文摘I.请根据录音,填写单词或把单词补充完整。II.听对话,选择正确的答案。1.What is Emily’s favorite animal?A.Dolphins.B.Lions.C.Elephants.D.Tigers.2.How fast can dolphins swim?A.10 miles per hour.B.20 miles per hour.C.30 miles per hour.D.40 miles per hour.
文摘Summer is my favorite season of the year.The weather is hot,but I don’t mind because there are so many fun things to do.In summer,I can swim in the pool with my friends.The cool water makes me feel really comfortable.
基金The National Key Research and Development Program under contract No.2024YFD2401404the Natural Science Foundation of Guangdong Province under contract No.2024A1515012696+2 种基金the Offshore Wind Power Joint Fund of Natural Science Foundation of Guangdong Province under contract No.2023A1515240004the Natural Science Foundation of Hainan Province under contract No.322MS154the Fund of Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization,Ministry of Agriculture and Rural Affairs,P.R.China under contract No.FREU2023-07。
文摘Tachypleus tridentatus,a critical biological resource used in Limulus Amebocyte Lysate(LAL),has experienced a sharp decline that is attracting global attention.Although artificial husbandry and breeding are promising strategies for promoting the proliferation of T.tridentatus,technological research is still in its infancy.Studying the behavioral characteristics during the reproductive period is crucial for identifying the environmental requirements of T.tridentatus.In this study,the behaviors of adult T.tridentatus were recorded continuously in an artificial aquaculture environment using underwater cameras.The behavior of adult T.tridentatus is mainly characterized by locomotion,feeding,and reproduction,which encompass a total of 11 types of behavior.The types of locomotion,including respiratory,swimming,climbing,and turning over,were coordinated with each other.Particularly,specific swimming patterns were utilized to efficiently conserve energy.Tachypleus tridentatus effectively utilized coordinated movements of its appendages to assist in feeding.This multi-organ coordinated feeding strategy allowed them to move quickly or avoid threats,thereby preventing food from being taken by others.The coordinated feeding pattern involving multiple organs enhances efficiency during rapid movement or evasion,protecting the food from being contested by other organisms.Competitive courtship and a monogamous mating strategy allowed T.tridentatus to efficiently find mates and lay eggs in suitable environments.Repeated spawning behaviors contributed to the high reproductive success rate.This study elucidated the ecological requirements of T.tridentatus from a behavioral perspective,thereby providing valuable references for implementing and optimizing its rearing environment.
基金supported by the Fundamental Research Funds for the Central Universities(No.30922010719).
文摘Underwater jet propulsion bio-inspired robots have typically been designed based on soft-bodied organisms, exhibiting relatively limited forms of locomotion. Scallop, a bivalve organism capable of jet propulsion, holds significant importance in the study of underwater motion mechanisms. In this study, we present theoretical fluid mechanics analysis and modeling of the three distinct motion stages of scallops, providing parameterized descriptions of scallop locomotion mechanisms. Accordingly, three-stage adaptive motion control for the scallop robot and model-based robot configuration optimization design were achieved. An experimental platform and a robot prototype were built to validate the accuracy of the motion model and the effectiveness of the control strategy. Additionally, based on the models, future optimization directions for the robot are proposed.
基金supported by the supported by the Spanish Ministry of Science,Innovation and Universities(MCIN/AEI/10.13039/501100011033)the European Union(NextGenerationEU/PRTR)through projects CGL2016-80820-R,PID2019-103936GB-C21,TED2021-129889B-I00,and RED2022-134338-T.
文摘Captive breeding and stocking are commonly employed strategies for enhancing fisheries and conserving endangered fish species.However,hatchery-raised fish often exhibit reduced performance in the wild,displaying alterations in physiological,morphological,and behavioral traits.We tested for differences in swimming capacity and metabolic traits between wild and hatchery-reared individuals of the Spanish toothcarp(Aphanius iberus)from 2 different populations.Furthermore,we experimentally tested if these changes translated into fitness differences after their stocking into the wild.There were significant differences in swimming capacity and metabolic traits between wild and hatchery-reared individuals and also between the 2 populations.Captive-bred individuals displayed consistently lower metabolic rates than wild individuals from the same population(30-76% lower).Critical swimming speed rather differed between the 2 populations.Sex-specific differences were observed in maximum and standard metabolic rates,with wild individuals and females generally exhibiting higher values but with some exceptions.During a 3-month experiment,survival rates did not significantly differ between wild and captive-bred fish.Captive-bred individuals started smaller but exhibited rapid growth during the experiment.Initially,larger captive-bred fish had lower body conditions than their wild counterparts,but these differences progressively diminished.In summary,captive-bred individuals of this fish species showed lower metabolic rates,although the differences with wild individuals slightly depended on sex and size.
基金funded by the Australian Research Council(DP180101801 awarded to K.M.)and The University of Queensland.
文摘Locomotion is thermally sensitive in ectotherms and therefore it is typically expressed differently among thermally heterogenous environments.Locomotion is a complex function,and whereas physiological and behavioral traits that infuence locomotor performance may respond to thermal variation throughout life,other contributing traits,like body shape,may have more restricted responses.How morphology affects locomotorperformance under variable temperature conditions is unknown.Here,we investigated 3 genetically distinct strains of zebrafsh,Danio rerio(AB,WIK,and Tu)with a shared multi-generational history at 28℃.After rearing fsh at 28℃,we measured prolonged swimming speed(Ucrit)at each of 6 temperatures(between 16℃ and 34℃).Speed was strongly positively correlated among temperatures,resulting in most amongindividual variation being temperature-independent(i.e.,fsh were relatively fast or slow across all temperatures).However,we also detectedsignifcant variation along 2 axes refecting temperature-dependent variation.Although strains differed in mean swimming performance,withinstrain(among-individual)patterns of speed variation were markedly consistent.Body shape and size explained signifcant variation amongindividuals in both temperature-independent and temperature-dependent axes of swimming speed variation.Notably,morphological traits thatwere most strongly associated with temperature-independent performance variation(i.e.,faster-slower)differed from those associated withtemperature-dependent(i.e.,hotter-colder)variation.Further,there were signifcant differences among strains in both the direction and strengthof association for specifc morphological traits.Our results suggest that thermally heterogenous environments could have complex effects onthe evolution of traits that contribute to whole organism performance traits.
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.
文摘In the mysterious depths of the ocean,robots glide between reefs and corals,avoid obstacles,navigate independently,and fulfil their tasks as if they had a vision that could penetrate the murkiness of the water.The Chinese company Chasing has developed a robot capable of diving to a depth of 350 metres.As an underwater photographer,lifeguard or swimming pool cleaner,it demonstrates the expertise the company has acquired over years of research and development work.
基金supported by the National Natural Science Foundation of China(No.41806182)the National Key R&D Program of China(No.2020YFD0900900)+1 种基金the Provincial Universities Basic Scientific Research Foundation in Zhejiang Province of China(No.2021ZJ004)the Science and Technology Project of Zhoushan(No.2020C21020).
文摘Swimming crab(Portunus trituberculatus)eggs contain abundant phospholipids and polyunsaturated fatty acids with specific bioactivities.However,more studies on the functions of other nutrients are needed.Here,a novel sialoglycopeptide from P.trituberculatus eggs,which was termed as Pt-SGP,was isolated with enzymolysis.Pt-SGP was a 6480-Da pure sialoglycopeptide.O-glycan units existed between peptides and sugars.Pt-SGP was composed of 10.69%protein,71.43%hexose,and 11.27%Neu5Gc acid.Analyzed with HPLC,GC-MS,and NMR spectrometry,the carbohydrate chain of Pt-SGP was{(4GlcNAc1-2Man1-3)/(4GlcNAc1-2Man1-6)Man1-6}/{4Glc1-4}Glc1-4Glc1-3GlcNAc1.The MS spectrometry analysis result showed that the peptide chain was Val-Ala-Thr*-Val-Ser*-Leu-Pro-Arg.The results on mice showed Pt-SGP could reduce body weight gain by 18.13%,white adipose weight by 28.57%,serum TC by 22.32,serum TG by 9.46%,serum LDL-C by 27.69%,hepatic TC by 73.21%,and hepatic TG by 25.20%.Furthernore,it could increase serum HDL-C by 75.96%,mitigate adipocyte size and hepatic lipid accumulation in high fat diet-fed mice.Pt-SGP significantly down-regulated C/EBPαsignaling and up-regulated AMPKαsignaling in the epididymal fat tissues.The findings indicate that Pt-SGP exhibits notable anti-obesity properties,and can potentially become a promising dietary supplement for anti-obesity.
基金supported by the Japan Society for the Promotion of Science(JSPS KAKENHI No.23H01373).
文摘The cutaneous ridges on dolphin skin have long been believed to effectively reduce friction drag, thereby contributing to overall drag reduction. However, since these skin ridges are oriented perpendicular to the swimming direction, they also generate additional pressure drag, raising questions about the impact of the shape-induced pressure forces on swimming. Inspired by the microvibrations observed on dolphin skin, we hypothesize that the microstructure on dolphin skin is not static but dynamically oscillates in the form of Longitudinal Micro-Ultrasonic Waves (LMUWs). To explore this, we carried out a series of Computational Fluid Dynamics (CFD) simulations based on Large Eddy Simulation (LES) model to investigate the impact of pressure drag on the total drag acting on an oscillating skin surface under realistic turbulent flow conditions. The results indicate that the dynamic skin oscillations induce a new dynamic Stokes boundary layer, which has the potential to convert pressure drag into a negative force, thereby reducing total drag under the influence of traveling LMUW excitations. Furthermore, a relative velocity ξ, defined as the difference between the wave speed c and the external flow speed U, is introduced to evaluate the drag-reduction effect dominated by pressure. The findings reveal that pressure drag remains negative when ξ > 0. As ξ increases, the thrust effect induced by negative pressure becomes increasingly significant, ultimately counteracting friction drag and eliminating total drag. This pressure-dominated drag reduction mechanism thus demonstrates a novel strategy for the drag reduction technology and the potential of unveiling the mysteries behind dolphin swimming.
基金Supported by the National Key Research and Development Program of China(No.2019YFD0901304)the Public Welfare Technology Application Research Project of Zhejiang(No.LGN21C190009)the Science and Technology Project of Zhoushan(No.2022C41003)。
文摘The early life stages of marine organisms are pivotal in shaping community dynamics and resource availability.In this study,we focused on Portunus trituberculatus,a crustacean integral to China's fisheries economy,and examined the effect of sea surface temperature(SST)in its critical early life stages on subsequent yields.To analyze the correlation between SST in different larval stages and the corresponding yield of P.trituberculatus,we simulated the transport and distribution of larvae from 2014 to 2022 by employing circulation models and Lagrangian particle tracking experiments(LPTE).In the five years(2014,2015,2016,2019,and 2020),particles were transported in a northwestern direction and moved in the direction of low SST.The distribution of particles in the megalopa stage(M stage)were located in the region of the lower temperature.In 2017,2018,and 2021,the particles were transported in a northeastern direction but they did not move with the gradient of low SST in these years,and the particles in the last M stage were located in the region where the SST was at the peak of the time period.In 2022,the distribution was observed for most of the particles in the southwestern part of Zhejiang coast,a small part of them were transported in the northwestern direction and a small amount of particles was distributed offshore along the northern area of the Zhejiang coast.The correlations between the SST at each stage of larvae with the corresponding year's yield showed that the yield of P.trituberculatus decreased significantly(R=-0.772,P=0.015)with increasing SST at the M stage.This study preliminarily explains the correlation between SST at the larval stage and the yield of P.trituberculatus and provides essential information for scientific stock enhancement in the future.
文摘Depression is a chronic,recurring and potentially life-threatening illness that affects up to 20%of the population across the world.Despite its prevalence and considerable impact on human,little is known about its pathogenesis.One of the major reasons is the restricted availability of validated animal models due to the absence of consensus on the pathology and etiology of depression.Besides,some core symptoms such as depressed mood,feeling of worthlessness,and recurring thoughts of death or suicide,are impossible to be modeled on laboratory animals.Currently,the criteria for identifying animal models of depression rely on either of the 2 principles：actions of known antidepressants and responses to stress.This review mainly focuses on the most widely used animal models of depression,including learned helplessness,chronic mild stress,and social defeat paradigms.Also,the behavioral tests for screening antidepressants,such as forced swimming test and tail suspension test,are also discussed.The advantages and major drawbacks of each model are evaluated.In prospective,new techniques that will be beneficial for developing novel animal models or detecting depression are discussed.
文摘Objective Striatum may be involved in depressive disorders according to the neuroimaging analysis and clinical data. However, no animal model at present supported the possible role of striatum in the pathogenesis of depression. In the present study, we have investigated the depressive-like behavior in mice recently intoxicated with 3-nitropropionic acid （3- NP）, a widely known toxin that selectively damages the striatum in the brain. Methods Mouse model was made with subacute systemic 3-NP treatment, and the depressive-like behavior was measured using the duration of immobility during forced swimming test （FST）. Results When the mice at day 15 post-intoxication just totally recovered from motor deficits, the duration of immobility in FST was significantly longer than that in controls. The depressive-like behavior was not due to the fatigue or general sickness following 3-NP intoxication and could be reversed by the antidepressant, desipramine hydrochloride. In two successive FST in 24 h interval, the depressive-like behavior could be observed again in subsequent FST （at day 16 post-intoxication）, and the mice presented a normal ＂learned helplessness＂. Conclusion A novel depression animal model could be established in mice during the initial period of recovery from 3-NP intoxication. The depression-like behavior might occur independently without involvement of cognitive defects, and the striatal lesions may underlie the depression-like behavior attributable to 3-NP intoxication.
文摘We investigated the concentration of trihalomethanes （THMs） in tap water and swimming pool water in the area of the Nakhon Path- om Municipality during the period April 2005-March 2006. The concentrations of total THMs, chloroform, bromodichloromethane, dibromochloromethane and bromoform in tap water were 12.70-41.74, 6.72-29.19, 1.12-11.75, 0.63-3.55 and 0.08-3.40 μg/L, respectively, whereas those in swimming pool water were 26.15-65.09, 9.50-36.97, 8.90-18.01, 5.19-22.78 and ND-6.56 μg/L, respectively. It implied that the concentration of THMs in swimming pool water was higher than those in tap water, particularly, brominated-THMs. Both tap water and swimming pool water contained concentrations of total THMs below the standards of the World Health Organization （WHO）, European Union （EU） and the United States Environmental Protection Agency （USEPA） phase Ⅰ, but 1 out of 60 tap water samples and 60 out of 72 swimming pool water samples contained those over the Standard of the USEPA phase Ⅱ. From the two cases of cancer risk assessment including Case Ⅰ Non-Swimmer and Case Ⅱ Swimmer, assessment of cancer risk of nonswimmers from exposure to THMs at the highest and the average concentrations was 4.43×10^-5 and 2.19×10^-5, respectively, which can be classified as acceptable risk according to the Standard of USEPA. Assessment of cancer risk of swimmers from exposure to THMs at the highest and the average concentrations was 1.47×10^-3 and 7.99×10^-4, respectively, which can be classified as unacceptable risk and needs to be improved. Risk of THMs exposure from swimming was 93.9%-94.2% of the total risk. Cancer risk of THMs concluded from various routes in descending order was： skin exposure while swimming, gastro-intestinal exposure from tap water intake, and skin exposure to tap water and gastro-intestinal exposure while swimming. Cancer risk from skin exposure while swimming was 94.18% of the total cancer risk.
