Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of ...Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of behavior in the invasive potential of animals is less studied.The common coqui frog,Eleutherodactylus coqui,is a highly successful invader in Hawai'i.We build on previous research characterizing changes in physiology and morphology to explore behavioral variation across the invasive range of coqui in Hawai'i.Coqui have expanded both outward and upward from their initial introduction site,andby comparing frogs from different densities and elevations-we specifically asked how the physiological challenges of high-elevation living interact with the competitive challenge of high-densities at population centers.To investigate whether differences in the field represent local adaptation or behavioral plasticity,we additionally evaluated behavior following acclimation to a shared laboratory environment.Although we identified only subtle behavioral variation among populations in the field,we found that individuals from all populations became less bold,active,and exploratory in the laboratory,converging on a similar behavioral phenotype.Alongside previous work,our results suggest that coqui adjust their behavior to local environmental conditions across their invasive range and that behavioral flexibility may contribute to invasive success.展开更多
Paternal predation risk can program offspring phenotypes via maternal responses and epigenetic marks of spermatozoa.However,the processes and consequences of this experience in biparental species are unknown.Here,we e...Paternal predation risk can program offspring phenotypes via maternal responses and epigenetic marks of spermatozoa.However,the processes and consequences of this experience in biparental species are unknown.Here,we examined how preconception and postconception paternal cat odor(CO)exposure affects anxiety-like behavior and antipredator response in Brandt’s voles(Lasiopodomys brandtii).We found that preconception paternal CO exposure inhibited maternal investment when offspring were raised by mothers alone,while postconception exposure increased paternal investment towards the offspring raised by both parents.The increased paternal behavior may be associated with an increasing grooming behavior received from their mates,which alleviated the anxiety-like behavior in CO-exposed males.Both paternal experiences increased the levels of anxiety-like behavior in adolescent offspring but differentially altered adult phenotypes.Specifcally,adult females from preconception CO-exposed fathers spent less time in defensive concealing,whereas the offspring of postconception CO-exposed fathers showed more in response to acute cat urine exposure.Correspondingly,baseline corticosterone levels were decreased and increased in these offspring,respectively.Our results indicate that in biparental species,paternal predation risk exposure affects offspring phenotypes in pathway-dependent and age-specifc manners and that only the presence of both parents can elicit adaptive responses to a high predation-risk environment.展开更多
The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HE...The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HEA),which is mediated by nano-twinning and phase transformation at cryogenic temperatures.During uniaxial tensile deformation at 77 K,the alloy exhibited the formation of high-density deformation nano-twinning,cross-twinning,stacking faults(SFs)and Lomer-Cottrell locks(L-C locks).Additionally,the lower stacking fault energy(SFE)at low temperatures promotes the formation of the 9R phase.The high-density twin boundaries effectively hinder dislocation movement,leading to the instability of plastic deformation and promoting the serrated flow behavior.Furthermore,the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior.Nano-twinning,SFs,cross-twinning,L-C locks and 9R phase collectively induce a dynamic Hall-Petch effect,enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K.Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.展开更多
Shape memory alloys(SMAs)and shape memory ceramics(SMCs)exhibit high recovery ability due to the martensitic transformation,which complicates the fracture mechanism of SMAs and SMCs.The phase field method,as a powerfu...Shape memory alloys(SMAs)and shape memory ceramics(SMCs)exhibit high recovery ability due to the martensitic transformation,which complicates the fracture mechanism of SMAs and SMCs.The phase field method,as a powerful numerical simulation tool,can efficiently resolve the microstructural evolution,multi-field coupling effects,and fracture behavior of SMAs and SMCs.This review begins by presenting the fundamental theoretical framework of the fracture phase field method as applied to SMAs and SMCs,covering key aspects such as the phase field modeling of martensitic transformation and brittle fracture.Subsequently,it systematically examines the phase field simulations of fracture behaviors in SMAs and SMCs,with particular emphasis on how crystallographic orientation,grain size,and grain boundary properties influence the crack propagation.Additionally,the interplay between martensite transformation and fracture mechanisms is analyzed to provide deeper insights into the material responses under mechanical loading.Finally,the review explores future prospects and emerging trends in phase field simulations of SMA and SMC fracture behavior,along with potential advancements in the fracture phase field method itself,including multi-physics coupling and enhanced computational efficiency for large-scale simulations.展开更多
Shale reservoirs have abundant bedding structures,which deeply alter the mechanical properties of rocks,and thus affect the reservoir stimulation performance.Previous research mostly focuses on the effects of parallel...Shale reservoirs have abundant bedding structures,which deeply alter the mechanical properties of rocks,and thus affect the reservoir stimulation performance.Previous research mostly focuses on the effects of parallel bedding on fracture propagation,while the mechanical properties and mechanisms of fracture propagation remain unclear for rocks with complex wavy bedding(e.g.China’s continentalorigin Gulong shale).Herein,a mixed phase-field fracture model of the wavy-bedding shale was applied,based on the local tension-compression decomposition phase field method(PFM)and geometric structure generation algorithm for the bedding with controllable morphological features.The parametric analysis of fracture propagation behaviors in the case of abundant complex bedding structures showed that with wavy bedding,the vertical fracture propagation rate is far higher than the horizontal propagation rate.Moreover,the development of branch fractures is suppressed during the fracturing process of the wavy-bedding sample,and the stimulated volume is limited,which is different from the characteristic of parallel bedding that promotes horizontal fracture initiation and propagation.The results showed that larger amplitudes,higher frequencies,higher inclination angles,and larger strengths of wavy bedding all promote the formation of vertical penetrating fractures and suppress the growth of branch fractures.Under such circumstances,it is hard to create a well-connected fracture network after fracturing.This research may provide a theoretical basis for understanding fracture behaviors in rocks with such complex wavy bedding.展开更多
Ti750s titanium alloy,a novel high-temperature titanium alloy designed for short-term service at elevated temperatures(700–750℃),has previously lacked comprehensive understanding of its hot processing behavior.In th...Ti750s titanium alloy,a novel high-temperature titanium alloy designed for short-term service at elevated temperatures(700–750℃),has previously lacked comprehensive understanding of its hot processing behavior.In this study,the high-temperature deformation behavior and microstructural evolution of the Ti750s alloy were systematically investigated through thermal simulation compression tests conducted at temperatures ranging from 900 to 1070℃and strain rates between 0.1 and 10 s⁻1.A hot processing map was constructed using the dynamic material model to optimize the hot processing parameters.The results indicated that the optimal processing window was between 1040 and 1070℃with a strain rate of 0.1 s⁻1.Processing within the instability region resulted in localized plastic deformation,manifesting as pronounced shear bands and a highly heterogeneous strain distribution;this region should be avoided during hot deformation.Within theα+βphase safety zone characterized by low power dissipation rates between 0.32 and 0.4,the primary deformation mechanism in this region was dynamic recovery(DRV),where the lamellarαgrains underwent deformation and rotation.Conversely,in theα+βphase safety zone with high-power dissipation rates between 0.45 and 0.52,dynamic spheroidization of theαphase and dynamic recrystallization(DRX)of theβphase occurred concurrently.In theβphase safety zone with low power dissipation rates between 0.32 and 0.51,the primary deformation mechanism consisted of DRV ofβgrains,accompanied by limited DRX.However,in theβphase safety zone with high-power dissipation rates exceeding 0.56,both DRV and DRX ofβgrains took place,resulted in a significant increase in the size and number of recrystallized grains compared to those observed under low power dissipation conditions.展开更多
Background:Prosocial behavior plays a crucial role in improving interpersonal relationships and social well-being,especially in times of crisis.The COVID-19 pandemic caused a severe humanitarian crisis,prompting gover...Background:Prosocial behavior plays a crucial role in improving interpersonal relationships and social well-being,especially in times of crisis.The COVID-19 pandemic caused a severe humanitarian crisis,prompting governments to implement measures such as social confinement.The main objective of the study was to analyze the psychological and sociodemographic variables that may predict prosocial behavior during quarantine.Methods:The sample consisted of 172 participants from Spain,divided into two groups based on whether they reported an increase in prosocial behaviors during quarantine.An online survey was administered to analyze the psychological and sociodemographic variables.Results:Overall,results demonstrate that emotional regulation,morality and age may predict prosocial behavior.Conclusions:Understanding the predictors of prosocial behavior during social crises is crucial for devising effective policies aimed at fostering community resilience and support networks,with particular attention to factors such as the capacity to regulate emotions,morality,and age.展开更多
Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosio...Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosion morphology and post-foil formation surface morphology of laser beam welded(LBW)sample and spin-formed sample,and compared the corrosion resistance and Cu foil formation ability of two samples in H_(2)SO_(4)/NaCl solution and CuSO_(4) reducing electrolyte.Results show that in H_(2)SO_(4) and NaCl solutions,LBW sample and spin-formed sample exhibit excellent passivation ability and corrosion resistance.Both samples show uniform corrosion morphologies and similar corrosion resistance in the strong acidic solution containing Cl^(-).Meanwhile,the Cu foil formation ability of the welded joint is similar to that of the spin-formed sample,and both samples obtain intact Cu foils with high-quality surfaces and small differences in properties.展开更多
Intelligence quotient(IQ)and adaptive behavior are the influencing factors of autism spectrum disorder(ASD)in children entering mainstream schools.This study explored the association between parental education level,I...Intelligence quotient(IQ)and adaptive behavior are the influencing factors of autism spectrum disorder(ASD)in children entering mainstream schools.This study explored the association between parental education level,IQ,and adaptive behavior in ASD groups.A total of 257 school-age ASD children were enrolled in our study from January 2017 to June 2021.Their parents completed a standard demographic form,including age at autism diagnosis,gender,school placement,and parents’educational background.The Chinese version of the Wechsler Intelligence Scale for Children,Fourth Edition(WISC-IV)was completed by a certified assessor for each enrolled child.Parents were interviewed on adaptive behavior using the Chinese version of the Adaptive Behavior Assessment System,Second Edition(ABAS-II).The average IQ of school-age ASD children was 76.88(standard deviation(SD)=22.62)and boys had higher IQ levels than girls.The IQ was positively correlated with age.The General Adaptive Composite(GAC)score was 82.47(SD=15.86)and adaptive behavior did not increase with age.ASD children who attended mainstream schools had better adaptive behavior profiles than other children.The mother’s education level showed a significant correlation with the IQ and adaptive behavior of autistic children,while the father’s education level did not.Consequently,better training and support for parents may help autistic children enter mainstream schools,with adaptive training being the most urgently required skill for parents.展开更多
The effects of nanostructuring on the mechanical and dry-sliding wear behaviors of a FeCoNi medium-entropy alloy(MEA)were systematically investigated through nano-indentation and ball-on-disc wear tests.The results sh...The effects of nanostructuring on the mechanical and dry-sliding wear behaviors of a FeCoNi medium-entropy alloy(MEA)were systematically investigated through nano-indentation and ball-on-disc wear tests.The results show that reducing the grain size down into the nano-meter regime,on the one hand,significantly elevates the hardness of the FeCoNi alloy,and on the other hand,facilitates the formation of a surface oxide layer.As a result,the wear rate of the nanocrystalline(NC)FeCoNi alloy is one order of magnitude lower than its coarse-grained counterpart.The NC FeCoNi alloy also exhibits obviously enhanced wear resistance compared with conventional NC Ni and Ni-based alloys in terms of both lower wear rate and friction coefficient.Such enhancement in tribological properties mainly stems from the improved strain hardening ability,owing to the inevitable concentration heterogeneity in MEA that imposes extra resistance to dislocation motion.展开更多
Autism spectrum disorders(ASD)are characterized by social and repetitive abnormalities.Although the ASD mouse model with Shank3b mutations is widely used in ASD research,the behavioral phenotype of this model has not ...Autism spectrum disorders(ASD)are characterized by social and repetitive abnormalities.Although the ASD mouse model with Shank3b mutations is widely used in ASD research,the behavioral phenotype of this model has not been fully elucidated.Here,a 3D-motion capture system and linear discriminant analysis were used to comprehensively record and analyze the behavioral patterns of male and female Shank3b mutant mice.It was found that both sexes replicated the core and accompanied symptoms of ASD,with significant sex differences.Further,Shank3b heterozygous knockout mice exhibited distinct autistic behaviors,that were significantly different from those those observed in the wild type and homozygous knockout groups.Our findings provide evidence for the inclusion of both sexes and experimental approaches to efficiently characterize heterozygous transgenic models,which are more clinically relevant in autistic studies.展开更多
Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess t...Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion sites.Scanner electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Pitting corrosion was observed in Mg-6Zn-2Fe,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Among the tests,the Mg-6Zn-2Ni alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential difference.Mechanical testing showed that Mg-6Zn-2Ni alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications.展开更多
The Diagnostic and Statistical Manual of Mental Disorders,5th Edition(DSM-5)(American Psychiatric Association,2013)defines autism spectrum disorder(ASD)as a complex neurodevelopmental disorder that begins in early chi...The Diagnostic and Statistical Manual of Mental Disorders,5th Edition(DSM-5)(American Psychiatric Association,2013)defines autism spectrum disorder(ASD)as a complex neurodevelopmental disorder that begins in early childhood and is accompanied by social communication deficits and repetitive stereotyped behaviors.展开更多
The effect of precipitation aging on the fracture behavior of cast Mg-14.23Gd-0.45Zr(wt.%)alloy at room temperature has been studied in this work.Uniaxial tensile and three-point bending tests were conducted on sample...The effect of precipitation aging on the fracture behavior of cast Mg-14.23Gd-0.45Zr(wt.%)alloy at room temperature has been studied in this work.Uniaxial tensile and three-point bending tests were conducted on samples peak-aged at 175,200,225,and 250 ℃.Notably,samples aged at 175 ℃ and 200 ℃ exhibited premature fracture during the uniaxial tensile test.Through fractographic observations of the tensile test samples and electron backscattered diffraction(EBSD)analysis on the samples sub-jected to three-point bending tests,a preferential formation of cleavage cracks in samples aged at 175 ℃ and 200 ℃ was identified as the reason for their premature fracture.The X-ray diffraction(XRD)results and transmission electron microscopy(TEM)observations of precipitates indicate that the dominant strengthening precipitates in all peak-aged samples are of theβ'phase,and their size significantly influences the formation of cleavage cracks.This phenomenon is attributed to the shearing mechanism of precipitates.Specifically,the smaller β'precipitates formed under the aging temperature of 175-200 ℃ are susceptible to dislocation shearing,leading to the formation of cleavage cracks.In contrast,the larger size of β'precipitates formed under the aging temperature of 225-250 ℃ provides resistance to shearing,resulting in the restrained formation of cleavage cracks and ultimately contributing to the enhancement of the ultimate tensile strength.展开更多
This paper theoretically studies the axisymmetric frictionless indentation of a transversely isotropic piezoelectric semiconductor(PSC)half-space subject to a rigid flatended cylindrical indenter.The contact area and ...This paper theoretically studies the axisymmetric frictionless indentation of a transversely isotropic piezoelectric semiconductor(PSC)half-space subject to a rigid flatended cylindrical indenter.The contact area and other surface of the PSC half-space are assumed to be electrically insulating.By the Hankel integral transformation,the problem is reduced to the Fredholm integral equation of the second kind.This equation is solved numerically to obtain the indentation behaviors of the PSC half-space,mainly including the indentation force-depth relation and the electric potential-depth relation.The results show that the effect of the semiconductor property on the indentation responses is limited within a certain range of variation of the steady carrier concentration.The dependence of indentation behavior on material properties is also analyzed by two different kinds of PSCs.Finite element simulations are conducted to verify the results calculated by the integral equation technique,and good agreement is demonstrated.展开更多
Dear Editor,alLuitol,Stress contributes significantly to many diseases in modern society.Numerous studies have revealed that exposure to stress leads to increased vulnerability to anxiety,depression,and other mood dis...Dear Editor,alLuitol,Stress contributes significantly to many diseases in modern society.Numerous studies have revealed that exposure to stress leads to increased vulnerability to anxiety,depression,and other mood disorders,which are often accompanied by conditions such as cardiovascular disease and cognitive impairments[1,2].展开更多
Captive environments often fail to resemble the wild environment in respects of limited space, unchanging habitat, lack of stimulus and contingency. Common animal welfare problems which occur in captive animals includ...Captive environments often fail to resemble the wild environment in respects of limited space, unchanging habitat, lack of stimulus and contingency. Common animal welfare problems which occur in captive animals include low behavioral diversity, abnormal behavior and excessive inactivity. Environmental enrichment, as an effective strategy to tackle these problems and promote mental health of captive animals, has been recognized as an important principal for captive animal management. Among all the enriehment techniques, olfactory enrichment is a simple and effective method for improving the well-being of the olfactory sensitive felids. Behavioral problems were observed in six Amur leopards Panthera pardus orientalis at Beijing Zoological Garden. These were held in the older type exhibits which have now been rebuilt. These behaviors include stereotypic behavior and excessive inactivity caused by the spatially limited enclosures with low levels of stimuli. To determine the effects of predator, prey, and herb odors as potential enrichment materials for captive leopards, we conducted olfactory enrichment experiments for the leopards and tested the effects of nutmeg Myristica fragrans, feces of roe deer Capreolus capreolus and urine of Amur tiger Panthera tigris altaica to test for an increase in behavioral repertoire and activity. Odors provided in this study were also believed to improve the psychological and physiological health of individuals. To standardize the method of presentation the odors were introduced to the enclosures by rubbing or spraying onto a clean towel. Our results show that the selected three odors effectively increased the behavioral diversity. Ten new behavior types were observed in the nutmeg experiment, eight in the feces of roe deer experiment and six in the tiger urine experiment. Among the three odors, cats responded to nutmeg for the longest duration, followed by tiger urine and feces of roe deer. Leopards showed more play behavior in presence of nutmeg while more investigatory behavior in presences of feces of roe deer and tiger urine. Providing novel odors increased the spatial use of the exhibit and the animal＇ s increased use of the logs, sleeping platforms and bars in the cages. Novel odors also significantly increased the overall activity of the leopards, but the effects were diminished in about three hours.展开更多
The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread ant...The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdis- ciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk for the survival of species and populations in an increasingly polluted world. We provide an integrative framework for behavioral ecotoxicology using Tinbergen＇s four postu- lates （causation and mechanism, development and ontogeny, function and fitness, and evolution- ary history and phylogenetic patterns）. The aims of this review are： 1） to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2） to demonstrate how study- ing ecotoxicology can promote behavior research; and 3） to identify areas of behavioral ecotoxicol- ogy that require further attention to promote the integration and growth of the field.展开更多
The TiSiN-Cu nanocomposite coating was deposited on F690 steel substrate by arc ion plating. The structure and composition, tribocorrosion behavior and anti-microbiologically influenced corrosion(MIC)properties of TiS...The TiSiN-Cu nanocomposite coating was deposited on F690 steel substrate by arc ion plating. The structure and composition, tribocorrosion behavior and anti-microbiologically influenced corrosion(MIC)properties of TiSiN-Cu coating were investigated. The results show that the TiSiN-Cu coating has unique nanocomposite structures. The results of tribocorrosion show that the potential and current change of F690 steel and TiSiN-Cu coatings tend to be opposite. The reason is that the F690 steel is non-passivated metal and the TiSiN-Cu coating has passivation phenomenon. The TiSiN-Cu coating possesses excellent tribocorrosion resistance. Cu ion released from TiSiN-Cu coating can effectively inhibit the corrosion caused by SRB.展开更多
β titanium alloys with bi-modal structure which exhibit improved strength-ductility combination and fatigue property are widely used in aviation and aerospace industry.However,owing to the small size of primary α(α...β titanium alloys with bi-modal structure which exhibit improved strength-ductility combination and fatigue property are widely used in aviation and aerospace industry.However,owing to the small size of primary α(αp) and nano-scaled multi variant distribution of secondary α platelets(αs),investigating the deformation behavior is really a challenging work.In this work,by applying transmission electron microscopy(TEM),the slip behavior in αp and transformed β matrix with different tensile strain was studied.After α/β solution treatment,the initial dislocation slips on {110} plane with <1 1 1> direction in β matrix.During furtherdeformation,(110),(101) and(1 1 2) multi slip is generated which shows a long straight cro s sing configuration.Dislocation cell is exhibited in β matrix at tensile strain above 20 %.Diffe rent from the solid solution treated sample,high density wavy dislocations are generated in transformedβ matrix.High fraction fine as hinders dislocation motion in β matrix effectively which in turn dominates the strength of the alloy.In primary α phase(αp),a core-shell structure is formed during deformation.Both pyramidal a+c slip and prismatic/basal a slip are generated in the shell layer.In core region,plastic deformation is governed by prismatic/basal a slip.Formation of the core-shell structure is the physical origin of the improved ductility.On one hand,the work hardening layer(shell) improves the strength of αp,which could deform compatibly with the hard transformed β matrix.Meanwhile,the center area(core) deforms homogeneously which will sustain plastic strain effectively and increase the ductility.This paper studies the slip behavior and reveals the origin of the improved strength-ductility combination in Bi-modal structure on a microscopic way,which will give theoretical advises for developing the next generation high strength β titanium alloys.展开更多
基金supported by the United States Department of Agriculture National Institute of Food and Agriculture Hatch project 1026333(ILLU-875-984 to K.M.S)a University of Ilinois Graduate College Master's Fellowship(to K.M.S)+2 种基金a University of Illinois Graduate College Travel Award(to K.M.S)Ilinois State Toll Highway Authority funding(to D.E and A.L.C)University of Illinois Laboratory Start-up funds(to E.K.F).
文摘Biological invasions are a major driver of global biodiversity loss,impacting endemic species,ecosystems,and economies.Although the influence of life history traits on invasive success is well-established,the role of behavior in the invasive potential of animals is less studied.The common coqui frog,Eleutherodactylus coqui,is a highly successful invader in Hawai'i.We build on previous research characterizing changes in physiology and morphology to explore behavioral variation across the invasive range of coqui in Hawai'i.Coqui have expanded both outward and upward from their initial introduction site,andby comparing frogs from different densities and elevations-we specifically asked how the physiological challenges of high-elevation living interact with the competitive challenge of high-densities at population centers.To investigate whether differences in the field represent local adaptation or behavioral plasticity,we additionally evaluated behavior following acclimation to a shared laboratory environment.Although we identified only subtle behavioral variation among populations in the field,we found that individuals from all populations became less bold,active,and exploratory in the laboratory,converging on a similar behavioral phenotype.Alongside previous work,our results suggest that coqui adjust their behavior to local environmental conditions across their invasive range and that behavioral flexibility may contribute to invasive success.
基金supported by grants from the National Natural Science Foundation of China(31770422 and 31900334)Natural Science Foundation of Jiangsu Province(BK20190910)+2 种基金Postdoctoral Science Foundation of China(2018M630610 and 2019T120468)Students’Project for Innovation and Entrepreneurship Training Program of Yangzhou University(XCX20230796)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Paternal predation risk can program offspring phenotypes via maternal responses and epigenetic marks of spermatozoa.However,the processes and consequences of this experience in biparental species are unknown.Here,we examined how preconception and postconception paternal cat odor(CO)exposure affects anxiety-like behavior and antipredator response in Brandt’s voles(Lasiopodomys brandtii).We found that preconception paternal CO exposure inhibited maternal investment when offspring were raised by mothers alone,while postconception exposure increased paternal investment towards the offspring raised by both parents.The increased paternal behavior may be associated with an increasing grooming behavior received from their mates,which alleviated the anxiety-like behavior in CO-exposed males.Both paternal experiences increased the levels of anxiety-like behavior in adolescent offspring but differentially altered adult phenotypes.Specifcally,adult females from preconception CO-exposed fathers spent less time in defensive concealing,whereas the offspring of postconception CO-exposed fathers showed more in response to acute cat urine exposure.Correspondingly,baseline corticosterone levels were decreased and increased in these offspring,respectively.Our results indicate that in biparental species,paternal predation risk exposure affects offspring phenotypes in pathway-dependent and age-specifc manners and that only the presence of both parents can elicit adaptive responses to a high predation-risk environment.
基金supported by the National Natural Science Foundation of China(Nos.52474403,52364050 and 52301137)Guizhou Provincial Program on Commercialization of Scientific and Technological Achievements(No.[2023]001)+2 种基金Guizhou Province Science and Technology Project(No.[2022]050)Guiyang city Science and Technology Project(No.[2023]48-16)the Central Government in Guidance of Local Science and Technology Development Funds(No.[2024]032).
文摘The serrated flow behavior,known as the Portevin-Le Chatelier(PLC)effect,is commonly observed during high-temperature deformation.In this study,we report a serrated flow behavior in FeCoCrNiMo0.2 high-entropy alloy(HEA),which is mediated by nano-twinning and phase transformation at cryogenic temperatures.During uniaxial tensile deformation at 77 K,the alloy exhibited the formation of high-density deformation nano-twinning,cross-twinning,stacking faults(SFs)and Lomer-Cottrell locks(L-C locks).Additionally,the lower stacking fault energy(SFE)at low temperatures promotes the formation of the 9R phase.The high-density twin boundaries effectively hinder dislocation movement,leading to the instability of plastic deformation and promoting the serrated flow behavior.Furthermore,the rapid and unstable transformation of the 9R phase contributes to the pronounced serrated flow behavior.Nano-twinning,SFs,cross-twinning,L-C locks and 9R phase collectively induce a dynamic Hall-Petch effect,enhancing the strength-ductility synergy and strain-hardening ability of deformed alloy at 77 K.Our work provides valuable insights into the mechanism of tensile deformation at cryogenic temperatures in single-phase FCC HEA.
基金supported by the National Natural Science Foundation of China(12202294)the Sichuan Science and Technology Program(2024NSFSC1346).
文摘Shape memory alloys(SMAs)and shape memory ceramics(SMCs)exhibit high recovery ability due to the martensitic transformation,which complicates the fracture mechanism of SMAs and SMCs.The phase field method,as a powerful numerical simulation tool,can efficiently resolve the microstructural evolution,multi-field coupling effects,and fracture behavior of SMAs and SMCs.This review begins by presenting the fundamental theoretical framework of the fracture phase field method as applied to SMAs and SMCs,covering key aspects such as the phase field modeling of martensitic transformation and brittle fracture.Subsequently,it systematically examines the phase field simulations of fracture behaviors in SMAs and SMCs,with particular emphasis on how crystallographic orientation,grain size,and grain boundary properties influence the crack propagation.Additionally,the interplay between martensite transformation and fracture mechanisms is analyzed to provide deeper insights into the material responses under mechanical loading.Finally,the review explores future prospects and emerging trends in phase field simulations of SMA and SMC fracture behavior,along with potential advancements in the fracture phase field method itself,including multi-physics coupling and enhanced computational efficiency for large-scale simulations.
基金supported by the Technology Project of CNPC(Grant No.2023ZZ08)the National Natural Science Foundation of China(Grant No.52274058)the USTC Research Funds of the Double First-Class Initiative(Grant No.YD2090002025).
文摘Shale reservoirs have abundant bedding structures,which deeply alter the mechanical properties of rocks,and thus affect the reservoir stimulation performance.Previous research mostly focuses on the effects of parallel bedding on fracture propagation,while the mechanical properties and mechanisms of fracture propagation remain unclear for rocks with complex wavy bedding(e.g.China’s continentalorigin Gulong shale).Herein,a mixed phase-field fracture model of the wavy-bedding shale was applied,based on the local tension-compression decomposition phase field method(PFM)and geometric structure generation algorithm for the bedding with controllable morphological features.The parametric analysis of fracture propagation behaviors in the case of abundant complex bedding structures showed that with wavy bedding,the vertical fracture propagation rate is far higher than the horizontal propagation rate.Moreover,the development of branch fractures is suppressed during the fracturing process of the wavy-bedding sample,and the stimulated volume is limited,which is different from the characteristic of parallel bedding that promotes horizontal fracture initiation and propagation.The results showed that larger amplitudes,higher frequencies,higher inclination angles,and larger strengths of wavy bedding all promote the formation of vertical penetrating fractures and suppress the growth of branch fractures.Under such circumstances,it is hard to create a well-connected fracture network after fracturing.This research may provide a theoretical basis for understanding fracture behaviors in rocks with such complex wavy bedding.
基金supported by the National basic scientific research projects(JCKY2021204A004)the National Ministries and Commissions Projects(2019-112hbz)the National Natural Science Foundation of China(No.52271113).
文摘Ti750s titanium alloy,a novel high-temperature titanium alloy designed for short-term service at elevated temperatures(700–750℃),has previously lacked comprehensive understanding of its hot processing behavior.In this study,the high-temperature deformation behavior and microstructural evolution of the Ti750s alloy were systematically investigated through thermal simulation compression tests conducted at temperatures ranging from 900 to 1070℃and strain rates between 0.1 and 10 s⁻1.A hot processing map was constructed using the dynamic material model to optimize the hot processing parameters.The results indicated that the optimal processing window was between 1040 and 1070℃with a strain rate of 0.1 s⁻1.Processing within the instability region resulted in localized plastic deformation,manifesting as pronounced shear bands and a highly heterogeneous strain distribution;this region should be avoided during hot deformation.Within theα+βphase safety zone characterized by low power dissipation rates between 0.32 and 0.4,the primary deformation mechanism in this region was dynamic recovery(DRV),where the lamellarαgrains underwent deformation and rotation.Conversely,in theα+βphase safety zone with high-power dissipation rates between 0.45 and 0.52,dynamic spheroidization of theαphase and dynamic recrystallization(DRX)of theβphase occurred concurrently.In theβphase safety zone with low power dissipation rates between 0.32 and 0.51,the primary deformation mechanism consisted of DRV ofβgrains,accompanied by limited DRX.However,in theβphase safety zone with high-power dissipation rates exceeding 0.56,both DRV and DRX ofβgrains took place,resulted in a significant increase in the size and number of recrystallized grains compared to those observed under low power dissipation conditions.
基金supported by the Ministry of Education,Culture and Sport(Predoctoral Contract University Faculty Training Program:FPU15/04335)later by the Spanish Public Administration“Ministerio de Universidades”and the European Union through the“NextGeneration EU”(Postdoctoral contract Margarita Salas).
文摘Background:Prosocial behavior plays a crucial role in improving interpersonal relationships and social well-being,especially in times of crisis.The COVID-19 pandemic caused a severe humanitarian crisis,prompting governments to implement measures such as social confinement.The main objective of the study was to analyze the psychological and sociodemographic variables that may predict prosocial behavior during quarantine.Methods:The sample consisted of 172 participants from Spain,divided into two groups based on whether they reported an increase in prosocial behaviors during quarantine.An online survey was administered to analyze the psychological and sociodemographic variables.Results:Overall,results demonstrate that emotional regulation,morality and age may predict prosocial behavior.Conclusions:Understanding the predictors of prosocial behavior during social crises is crucial for devising effective policies aimed at fostering community resilience and support networks,with particular attention to factors such as the capacity to regulate emotions,morality,and age.
基金Key Research and Development Program of Shaanxi Province(2022GY-410)Funding of Western Titanium Technologies Co.,Ltd(WX2210)。
文摘Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosion morphology and post-foil formation surface morphology of laser beam welded(LBW)sample and spin-formed sample,and compared the corrosion resistance and Cu foil formation ability of two samples in H_(2)SO_(4)/NaCl solution and CuSO_(4) reducing electrolyte.Results show that in H_(2)SO_(4) and NaCl solutions,LBW sample and spin-formed sample exhibit excellent passivation ability and corrosion resistance.Both samples show uniform corrosion morphologies and similar corrosion resistance in the strong acidic solution containing Cl^(-).Meanwhile,the Cu foil formation ability of the welded joint is similar to that of the spin-formed sample,and both samples obtain intact Cu foils with high-quality surfaces and small differences in properties.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LGF20H090015)。
文摘Intelligence quotient(IQ)and adaptive behavior are the influencing factors of autism spectrum disorder(ASD)in children entering mainstream schools.This study explored the association between parental education level,IQ,and adaptive behavior in ASD groups.A total of 257 school-age ASD children were enrolled in our study from January 2017 to June 2021.Their parents completed a standard demographic form,including age at autism diagnosis,gender,school placement,and parents’educational background.The Chinese version of the Wechsler Intelligence Scale for Children,Fourth Edition(WISC-IV)was completed by a certified assessor for each enrolled child.Parents were interviewed on adaptive behavior using the Chinese version of the Adaptive Behavior Assessment System,Second Edition(ABAS-II).The average IQ of school-age ASD children was 76.88(standard deviation(SD)=22.62)and boys had higher IQ levels than girls.The IQ was positively correlated with age.The General Adaptive Composite(GAC)score was 82.47(SD=15.86)and adaptive behavior did not increase with age.ASD children who attended mainstream schools had better adaptive behavior profiles than other children.The mother’s education level showed a significant correlation with the IQ and adaptive behavior of autistic children,while the father’s education level did not.Consequently,better training and support for parents may help autistic children enter mainstream schools,with adaptive training being the most urgently required skill for parents.
基金supported by the Science and Technology Development Program of Jilin Province,China(No.20160520007JH)the Major Science and Technology Special Project in Jilin Province,China(No.20210301024GX)the National Natural Science Foundation of China(Nos.51601067,51775266,52301169).
文摘The effects of nanostructuring on the mechanical and dry-sliding wear behaviors of a FeCoNi medium-entropy alloy(MEA)were systematically investigated through nano-indentation and ball-on-disc wear tests.The results show that reducing the grain size down into the nano-meter regime,on the one hand,significantly elevates the hardness of the FeCoNi alloy,and on the other hand,facilitates the formation of a surface oxide layer.As a result,the wear rate of the nanocrystalline(NC)FeCoNi alloy is one order of magnitude lower than its coarse-grained counterpart.The NC FeCoNi alloy also exhibits obviously enhanced wear resistance compared with conventional NC Ni and Ni-based alloys in terms of both lower wear rate and friction coefficient.Such enhancement in tribological properties mainly stems from the improved strain hardening ability,owing to the inevitable concentration heterogeneity in MEA that imposes extra resistance to dislocation motion.
基金National Science and Technology Innovation 2030-Major Project of China(2021ZD0201003 and 2022ZD0208300)National Natural Science Foundation of China(32171092)+3 种基金Shenzhen Key Basic Research Project(JCYJ20220818100805013)Shenzhen Key Laboratory of Viral Vectors for Biomedicine(ZDSYS20200811142401005)Guangdong Provincial Medical Products Administration Key Laboratory of Quality Control Technology for Virus-Based Therapeutics(2020ZDB26)Guangdong Provincial Medical Products Administration(2022ZDZ13).
文摘Autism spectrum disorders(ASD)are characterized by social and repetitive abnormalities.Although the ASD mouse model with Shank3b mutations is widely used in ASD research,the behavioral phenotype of this model has not been fully elucidated.Here,a 3D-motion capture system and linear discriminant analysis were used to comprehensively record and analyze the behavioral patterns of male and female Shank3b mutant mice.It was found that both sexes replicated the core and accompanied symptoms of ASD,with significant sex differences.Further,Shank3b heterozygous knockout mice exhibited distinct autistic behaviors,that were significantly different from those those observed in the wild type and homozygous knockout groups.Our findings provide evidence for the inclusion of both sexes and experimental approaches to efficiently characterize heterozygous transgenic models,which are more clinically relevant in autistic studies.
基金financially supported by the Key Scientific Research Project in Shanxi Province,China(No.202102050201003)the National Natural Science Foundation of China(No.52071227)+2 种基金the Natural Science Foundation of Shanxi Province,China(No.202103021223293)the Central Guiding Science and Technology Development of Local Fund,China(No.YDZJSK20231A046)the Postgraduate Education Innovation Project of Shanxi Province,China(No.2023Y686)。
文摘Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion sites.Scanner electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Pitting corrosion was observed in Mg-6Zn-2Fe,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Among the tests,the Mg-6Zn-2Ni alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential difference.Mechanical testing showed that Mg-6Zn-2Ni alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LTGY24H090005)the Autism Research Special Fund of Zhejiang Foundation for Disabled Persons(No.2023006)。
文摘The Diagnostic and Statistical Manual of Mental Disorders,5th Edition(DSM-5)(American Psychiatric Association,2013)defines autism spectrum disorder(ASD)as a complex neurodevelopmental disorder that begins in early childhood and is accompanied by social communication deficits and repetitive stereotyped behaviors.
基金National Natural Science Foundation of China(Nos.52271107,and 51701218)Natural Science Foundation of Shandong Province(No.ZR2021ME241)+1 种基金Natural Science Foundation of Liaoning Province(No.2020-MS-004)Bintech-IMR R&D Program(GYY-JSBU-2022-012).
文摘The effect of precipitation aging on the fracture behavior of cast Mg-14.23Gd-0.45Zr(wt.%)alloy at room temperature has been studied in this work.Uniaxial tensile and three-point bending tests were conducted on samples peak-aged at 175,200,225,and 250 ℃.Notably,samples aged at 175 ℃ and 200 ℃ exhibited premature fracture during the uniaxial tensile test.Through fractographic observations of the tensile test samples and electron backscattered diffraction(EBSD)analysis on the samples sub-jected to three-point bending tests,a preferential formation of cleavage cracks in samples aged at 175 ℃ and 200 ℃ was identified as the reason for their premature fracture.The X-ray diffraction(XRD)results and transmission electron microscopy(TEM)observations of precipitates indicate that the dominant strengthening precipitates in all peak-aged samples are of theβ'phase,and their size significantly influences the formation of cleavage cracks.This phenomenon is attributed to the shearing mechanism of precipitates.Specifically,the smaller β'precipitates formed under the aging temperature of 175-200 ℃ are susceptible to dislocation shearing,leading to the formation of cleavage cracks.In contrast,the larger size of β'precipitates formed under the aging temperature of 225-250 ℃ provides resistance to shearing,resulting in the restrained formation of cleavage cracks and ultimately contributing to the enhancement of the ultimate tensile strength.
基金Project supported by the National Natural Science Foundation of China(Nos.12072209,U21A2043012192211)+1 种基金the Natural Science Foundation of Hebei Province of China(No.A2020210009)the S&T Program of Hebei Province of China(No.225676162GH)。
文摘This paper theoretically studies the axisymmetric frictionless indentation of a transversely isotropic piezoelectric semiconductor(PSC)half-space subject to a rigid flatended cylindrical indenter.The contact area and other surface of the PSC half-space are assumed to be electrically insulating.By the Hankel integral transformation,the problem is reduced to the Fredholm integral equation of the second kind.This equation is solved numerically to obtain the indentation behaviors of the PSC half-space,mainly including the indentation force-depth relation and the electric potential-depth relation.The results show that the effect of the semiconductor property on the indentation responses is limited within a certain range of variation of the steady carrier concentration.The dependence of indentation behavior on material properties is also analyzed by two different kinds of PSCs.Finite element simulations are conducted to verify the results calculated by the integral equation technique,and good agreement is demonstrated.
基金supported by grants from the National Natural Science Foundation of China(32200826,32230042,and U20A20224)the Shenzhen Medical Research Fund(B2302004)+1 种基金the Shenzhen Science and Technology Program(JCYJ20220530154412028)the Financial Support for Outstanding Talents Training Fund in Shenzhen,and the Natural Science Foundation of Hebei Province(F2022201037).
文摘Dear Editor,alLuitol,Stress contributes significantly to many diseases in modern society.Numerous studies have revealed that exposure to stress leads to increased vulnerability to anxiety,depression,and other mood disorders,which are often accompanied by conditions such as cardiovascular disease and cognitive impairments[1,2].
基金founded by the Knowledge Innovation Project of the Chinese Academy of Sciences (CXTDS2005-4)the Natural Scientific Foundation of China (No.30230080,No.30670267)
文摘Captive environments often fail to resemble the wild environment in respects of limited space, unchanging habitat, lack of stimulus and contingency. Common animal welfare problems which occur in captive animals include low behavioral diversity, abnormal behavior and excessive inactivity. Environmental enrichment, as an effective strategy to tackle these problems and promote mental health of captive animals, has been recognized as an important principal for captive animal management. Among all the enriehment techniques, olfactory enrichment is a simple and effective method for improving the well-being of the olfactory sensitive felids. Behavioral problems were observed in six Amur leopards Panthera pardus orientalis at Beijing Zoological Garden. These were held in the older type exhibits which have now been rebuilt. These behaviors include stereotypic behavior and excessive inactivity caused by the spatially limited enclosures with low levels of stimuli. To determine the effects of predator, prey, and herb odors as potential enrichment materials for captive leopards, we conducted olfactory enrichment experiments for the leopards and tested the effects of nutmeg Myristica fragrans, feces of roe deer Capreolus capreolus and urine of Amur tiger Panthera tigris altaica to test for an increase in behavioral repertoire and activity. Odors provided in this study were also believed to improve the psychological and physiological health of individuals. To standardize the method of presentation the odors were introduced to the enclosures by rubbing or spraying onto a clean towel. Our results show that the selected three odors effectively increased the behavioral diversity. Ten new behavior types were observed in the nutmeg experiment, eight in the feces of roe deer experiment and six in the tiger urine experiment. Among the three odors, cats responded to nutmeg for the longest duration, followed by tiger urine and feces of roe deer. Leopards showed more play behavior in presence of nutmeg while more investigatory behavior in presences of feces of roe deer and tiger urine. Providing novel odors increased the spatial use of the exhibit and the animal＇ s increased use of the logs, sleeping platforms and bars in the cages. Novel odors also significantly increased the overall activity of the leopards, but the effects were diminished in about three hours.
基金JPS was funded by the National Science Foundation （IOS1257590）. The sym- posium from which this paper emerged was funded by the Animal Behavior Society.
文摘The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdis- ciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk for the survival of species and populations in an increasingly polluted world. We provide an integrative framework for behavioral ecotoxicology using Tinbergen＇s four postu- lates （causation and mechanism, development and ontogeny, function and fitness, and evolution- ary history and phylogenetic patterns）. The aims of this review are： 1） to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2） to demonstrate how study- ing ecotoxicology can promote behavior research; and 3） to identify areas of behavioral ecotoxicol- ogy that require further attention to promote the integration and growth of the field.
基金supported financially by the National Key R&D Program of China (No. 2016YFB0300604)the National Natural Science Foundation of China (Nos. 51575510 and 51771221)
文摘The TiSiN-Cu nanocomposite coating was deposited on F690 steel substrate by arc ion plating. The structure and composition, tribocorrosion behavior and anti-microbiologically influenced corrosion(MIC)properties of TiSiN-Cu coating were investigated. The results show that the TiSiN-Cu coating has unique nanocomposite structures. The results of tribocorrosion show that the potential and current change of F690 steel and TiSiN-Cu coatings tend to be opposite. The reason is that the F690 steel is non-passivated metal and the TiSiN-Cu coating has passivation phenomenon. The TiSiN-Cu coating possesses excellent tribocorrosion resistance. Cu ion released from TiSiN-Cu coating can effectively inhibit the corrosion caused by SRB.
基金supported financially by the National Natural Science Foundation of China (Nos. 51671158 and 51621063)the National Program on Key Basic Research Project (No. 2014CB644003)the Programme of Introducing Talents of Discipline to Universities (No. PB2018008)。
文摘β titanium alloys with bi-modal structure which exhibit improved strength-ductility combination and fatigue property are widely used in aviation and aerospace industry.However,owing to the small size of primary α(αp) and nano-scaled multi variant distribution of secondary α platelets(αs),investigating the deformation behavior is really a challenging work.In this work,by applying transmission electron microscopy(TEM),the slip behavior in αp and transformed β matrix with different tensile strain was studied.After α/β solution treatment,the initial dislocation slips on {110} plane with <1 1 1> direction in β matrix.During furtherdeformation,(110),(101) and(1 1 2) multi slip is generated which shows a long straight cro s sing configuration.Dislocation cell is exhibited in β matrix at tensile strain above 20 %.Diffe rent from the solid solution treated sample,high density wavy dislocations are generated in transformedβ matrix.High fraction fine as hinders dislocation motion in β matrix effectively which in turn dominates the strength of the alloy.In primary α phase(αp),a core-shell structure is formed during deformation.Both pyramidal a+c slip and prismatic/basal a slip are generated in the shell layer.In core region,plastic deformation is governed by prismatic/basal a slip.Formation of the core-shell structure is the physical origin of the improved ductility.On one hand,the work hardening layer(shell) improves the strength of αp,which could deform compatibly with the hard transformed β matrix.Meanwhile,the center area(core) deforms homogeneously which will sustain plastic strain effectively and increase the ductility.This paper studies the slip behavior and reveals the origin of the improved strength-ductility combination in Bi-modal structure on a microscopic way,which will give theoretical advises for developing the next generation high strength β titanium alloys.
