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Positive and negative risk-taking behaviors in adolescents:Distinct characteristics,interrelationships,and influencing factors
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作者 Jun-Jie Zhang En-Na Wang 《World Journal of Psychiatry》 2025年第6期21-33,共13页
Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has f... Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has focused predominantly on the adverse aspects of risk-taking(i.e.,negative risk-taking),overlooked the positive counterpart(i.e.,positive risk-taking),and lacked a detailed examination of both.This study aims to elucidate the distinct characteristics and interrelationships of positive and negative risk-taking behaviors among adoles-cents and to identify the key factors that influence these behaviors.Through a comprehensive synthesis of theoretical and empirical literature,we explore the multifaceted nature of risk-taking,highlighting its complex influencing factors,including individual traits,family dynamics,peer influence,school environment,and broader community contexts.By identifying the shared and unique factors contributing to positive and negative risk-taking behaviors,we can enable adolescents to navigate this complex stage of life and design targeted interventions.Future research directions include the application of person-centered approaches,the implementation of longitudinal tracking and the interactive effects of influencing factors,among other aspects. 展开更多
关键词 ADOLESCENCE Positive risk-taking Negative risk-taking Distinct characteristics INTERRELATIONSHIPS Influencing factors
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Development of a Self-Assessment Questionnaire for Nurses’ Risk-Taking Behavior in Medication
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作者 Yayoi Imura Chiharu Akazawa 《Health》 2022年第1期1-22,共22页
<strong>Purpose:</strong> The purpose of this study was to prepare a self-assessment questionnaire for nurses’ risk-taking behavior (RTB) in medication and to develop a reliable and valid questionnaire. &... <strong>Purpose:</strong> The purpose of this study was to prepare a self-assessment questionnaire for nurses’ risk-taking behavior (RTB) in medication and to develop a reliable and valid questionnaire. <strong>Method: </strong>In the first study, a draft of the self-evaluation questionnaire for nurses’ RTB in medication was prepared based on the literature study and qualitative analysis of important case information included in the Project to Collect Medical Near-miss/Adverse Event Information Annual Report of the Ministry of Health, Labor and Welfare. Following the studies, face validity was confirmed, and a questionnaire survey was conducted for nurses who oversee medication nationwide to verify the reliability and validity. <strong>Result: </strong>The number of subjects was 586 (valid response rate: 94.1%). Item analysis and exploratory factor analysis showed that 4 factors and 12 items for the RTBs in daily life and 4 factors and 20 items for RTBs in medication could be extracted. Confirmatory factor analysis confirmed the fit of the hypothetical model obtained by exploratory factor analysis. In addition, Cronbach’s α coefficient was 0.888. Thus, high reliability and validity were obtained. A correlation was found by comparing the total scores of each RTB factor with the incident/accident group, and a standard for self-evaluation value could be established (p < 0.01). <strong>Conclusions: </strong>We were able to develop a self-assessment questionnaire for nurses’ risk-taking behavior in medication. This questionnaire will be used by nurses to find out their trends. 展开更多
关键词 Self-Assessment Questionnaire risk-taking behavior Nurses MEDICATION
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Daily activity rhythms, chronotypes, and risk-taking behavior in the signal crayfish
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作者 Valerio SBRAGAGLIA Thomas BREITHAUPT 《Current Zoology》 SCIE CAS CSCD 2022年第2期177-183,共7页
Consistent inter-individual differences in daily activity rhythms(i.e.,chronotypes)can have ecological consequences in determining access to food resources and avoidance of predators.The most common measure to charact... Consistent inter-individual differences in daily activity rhythms(i.e.,chronotypes)can have ecological consequences in determining access to food resources and avoidance of predators.The most common measure to characterize chronotypes in animals as well as humans is the onset of activity(i.e.,early or late chronotypes).However,daily activity rhythms may also differ in the relative amount of activity displayed at particular time periods.Moreover,chronotypes may also be linked to other consistent inter-individual differences in behavior(i.e.,personality),such as the propensity to take risks.Here,we used the signal crayfish Pacifastacus leniusculusto test the presence of chronotypes and risk-taking personality traits and a potential behavioral syndrome between these traits.We first exposed crayfish to 5 days of light-darkness to measure daily activity rhythms and then we applied a visual predator-simulating stimulus in 2 different contexts(neutral and food).Our results showed consistent(i.e.,across 5 days)inter-individual differences in the relative nocturnal activity displayed in the early and middle,but not in the late part of darkness hours.Moreover,while crayfish displayed inter-individual differences in risk-taking behavior,these were not found to be consistent across 2 contexts.Therefore,we were not able to formally test a behavioral syndrome between these 2 traits.In conclusion,our study provides the first evidence of chronotypes in the relative amount of activity displayed at particular time periods.This could be a valuable information for applied ecological aspects related to the signal crayfish,which is a major invasive species of freshwater ecosystems. 展开更多
关键词 behavioral syndrome biological rhythms BOLDNESS FEEDING locomotor activity
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Corporate Governance,Macroprudential Regulation,and Bank Risk-Taking
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作者 Hu Xiliang Han Xiulian Sun He 《Contemporary Social Sciences》 2025年第1期31-46,共16页
Effective corporate governance and sound macroprudential policies are crucial to the stability and sustainable development of the banking sector in China.This paper uses panel data sets from 31 listed Chinese commerci... Effective corporate governance and sound macroprudential policies are crucial to the stability and sustainable development of the banking sector in China.This paper uses panel data sets from 31 listed Chinese commercial banks between 2007 and 2023 to examine how corporate governance and macroprudential regulation influence bank risk-taking.To achieve this,we constructed a set of micro-level corporate governance indicators.The findings show that corporate governance significantly reduces bank risk-taking,while macroprudential regulation positively moderates this relationship.Furthermore,business diversification and loan concentration are the key mechanisms through which corporate governance mitigates risk-taking.We confirmed the soundness of these findings by using robust econometric techniques,including difference-in-differences,system GMM,and alternative independent variables.This study provides valuable insights for optimizing bank capital structures,enhancing corporate governance,improving personnel management,and clarifying the roles of regulators in refining the macroprudential regulatory framework. 展开更多
关键词 corporate governance macroprudential regulation bank risk-taking
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Risk-taking path choice behaviors under ATIS in transportation networks with demand uncertainty 被引量:2
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作者 Shao, Hu Tian, Qiong +1 位作者 Yuan, Xiaoming Wang, Guodong 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期43-48,共6页
A new travel time reliability-based traffic assignment model is proposed to investigate the effects of an advanced transportation information system (ATIS) on drivers' risk-taking path choice behaviours in transpo... A new travel time reliability-based traffic assignment model is proposed to investigate the effects of an advanced transportation information system (ATIS) on drivers' risk-taking path choice behaviours in transportation networks with demand uncertainty. In the model, drivers are divided into two classes. The first class is not equipped with ATIS, while the second class is equipped with ATIS. Different risk-taking path choice behaviours of the two classes are studied, respectively. A corresponding mixed equilibrium traffic assignment model is formulated as a variational inequality problem in terms of path flows, which is solved by a heuristic solution algorithm. Numerical results indicate that the ATIS can influence the drivers' risk-taking path choice behaviours and the total system travel time in transportation networks with demand uncertainty. It is also found that under higher demand levels, the benefits of ATIS for network performance enhancement may be more obvious. 展开更多
关键词 risk-taking path choice behaviours advanced transportation information system (ATIS) demand uncertainty traffic assignment problem variational inequality
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Psychometric properties of the Chinese-version Behavioral Inhibition System/Behavioral Activation System Scales among stroke survivors with depressive symptoms 被引量:1
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作者 Dan Shi Yuen Yu Chong +1 位作者 Lijuan Zhou Ho Yu Cheng 《International Journal of Nursing Sciences》 2025年第1期74-80,共7页
Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectio... Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectional study was conducted at four comprehensive hospitals in Taizhou,Jiangsu,China.A sample of 232 first-ever stroke survivors were recruited from June to August 2023.Validity was examined using face validity and construct validity,which used confirmatory factor analysis(CFA)and known-group analysis.Reliability was evaluated by internal consistency and test-retest reliability.Results:The BIS/BAS scales demonstrated satisfactory face validity.The findings of CFAs supported the original four-factor structure of BAS-reward,BAS-drive,BAS-fun seeking,and BIS with acceptable model fit indices.Discriminative validity,assessed via known-group analysis,indicated that stroke survivors with probable depression had significantly lower mean BAS-reward,BAS-drive,and BAS-fun seeking scores(P<0.001)and a higher mean BIS score(P=0.028)compared to those without probable depression.The internal consistency,measured by Cronbach’s a coefficients for the subscales,ranged from 0.669 to 0.964.Test-retest reliability,assessed using intra-class correlation coefficients,ranged from 0.61 to 0.93.Conclusions:The Chinese version of the BIS/BAS scales could be a reliable and valid instrument for measuring behavioral activation among stroke survivors. 展开更多
关键词 behavior DEPRESSION Reliability STROKE Validity
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Unveiling the brain’s symphony:exploring the necessity and sufficiency of neural networks in behavior control
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作者 Fernando Jose Bustos 《Neural Regeneration Research》 SCIE CAS 2025年第1期186-187,共2页
Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully a... Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established. 展开更多
关键词 behavior CONNECTIVITY NEURAL
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The growth behavior and performance of microarc oxidation coating on AZ91/Ti composite: Influence of Ti-reinforcement phase and electrolyte 被引量:1
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作者 Jinchao Jiao Yongrui Gu +4 位作者 Jin Zhang Yong Lian Xintao Li Kaihong Zheng Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第3期1160-1175,共16页
Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,... Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed. 展开更多
关键词 Magnesium matrix composites Ti-reinforcement Micro-arc oxidation Growth behavior
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Features and classification of solid solution behavior of ternary Mg alloys 被引量:1
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作者 Tao Chen Yuan Yuan +6 位作者 Jun Wang Jiajia Wu Bin Wang Xianhua Chen Nele Moelans Jingfeng Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第6期2522-2539,共18页
The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg al... The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work. 展开更多
关键词 Mg alloys Solution behavior Phase diagram Alloy design
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Tribological behaviors of AZ91D magnesium alloy under the lubrication of oil suspended synthetic magnesium silicate hydroxide nanotubes 被引量:1
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作者 Y.L.Yin H.L.Yu +7 位作者 H.M.Wang X.C.Ji Z.Y.Song X.Y.Zhou M.Wei P.J.Shi W.Zhang C.F.Zhao 《Journal of Magnesium and Alloys》 2025年第1期379-397,共19页
Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological b... Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological behavior of AZ91D magnesium alloy rubbed against GCr15 steel was studied under lubricating oil with surface-modified MSH nanotubes as additives.The effects of the concentration,applied load,and reciprocating frequency on the friction and wear of the AZ91D alloy were studied using an SRV-4 sliding wear tester.Results show a decrease of 18.7–68.5%in friction coefficient,and a reduction of 19.4–54.3%in wear volume of magnesium alloy can be achieved by applying the synthetic serpentine additive under different conditions.A suspension containing 0.3 wt.%MSH was most efficient in reducing wear and friction.High frequency and medium load were more conducive to improving the tribological properties of magnesium alloys.A series of beneficial physical and chemical processes occurring at the AZ91D alloy/steel interface can be used to explain friction and wear reduction based on the characterization of the morphology,chemical composition,chemical state,microstructure,and nanomechanical properties of the worn surface.The synthetic MSH,with serpentine structure and nanotube morphology,possesses excellent adsorbability,high chemical activity,and good self-lubrication and catalytic activity.Therefore,physical polishing,tribochemical reactions,and physicalchemical depositions can occur easily on the sliding contacts.A dense tribolayer with a complex composition and composite structure was formed on the worn surface.Its high hardness,good toughness and plasticity,and prominent lubricity resulted in the improvement of friction and wear,making the synthetic MSH a promising efficient oil additive for magnesium alloys under boundary and mixed lubrication. 展开更多
关键词 Magnesium alloy Oil lubrication Tribological behavior Magnesium silicate hydroxide SERPENTINE
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The Characteristics and Intervention Strategies of Novice Teachers’Inappropriate Behaviors in Classroom Teaching 被引量:1
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作者 Guoqing Yu 《Journal of Contemporary Educational Research》 2025年第2期46-56,共11页
This study aims to explore the characteristics of novice teachers’inappropriate behaviors in classroom teaching and their intervention strategies.With the continuous improvement of education quality,novice teachers f... This study aims to explore the characteristics of novice teachers’inappropriate behaviors in classroom teaching and their intervention strategies.With the continuous improvement of education quality,novice teachers face increasing challenges in teaching practice.Their inappropriate behaviors not only affect the classroom atmosphere but may also negatively impact students’learning outcomes.Therefore,researching the characteristics of novice teachers’inappropriate behaviors and their intervention strategies holds significant scientific and social value.This study employs a combination of quantitative and qualitative methods to analyze the behavioral patterns of novice teachers in classroom teaching and proposes corresponding intervention strategies.The results indicate that novice teachers’inappropriate behaviors mainly manifest as poor classroom management,monotonous teaching methods,and insufficient interaction with students.Based on these findings,the study proposes a series of effective intervention strategies,including enhancing teacher training,optimizing teaching design,and promoting positive interactions between teachers and students.The conclusions of the study not only provide practical guidance for educational practice but also point out directions for future research,emphasizing the crucial role of teacher professional development in improving teaching quality. 展开更多
关键词 Novice teachers Inappropriate behaviors Intervention strategies Teaching quality Teacher professional development
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Effect of initial microstructure on performance and corrosion behavior of GH4169 superalloy joint produced by linear friction welding 被引量:1
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作者 Xiawei YANG Tingxi MENG +5 位作者 Yu SU Rui XU Zhenguo GUO Yaxin XU Tiejun MA Wenya LI 《Chinese Journal of Aeronautics》 2025年第3期662-675,共14页
The pre-weld heat treatment was carried out to obtain different initial microstructures of the GH4169 superalloy,and then Linear Friction Welding(LFW)was performed.The effect of the pre-weld heat treatment on the micr... The pre-weld heat treatment was carried out to obtain different initial microstructures of the GH4169 superalloy,and then Linear Friction Welding(LFW)was performed.The effect of the pre-weld heat treatment on the microstructure evolution and mechanical properties of the joint was analyzed,and the joint electrochemical corrosion behavior as well as the hot corrosion behavior was studied.The results show that the joint hardness of Base Metal(BM)increases after pre-weld heat treatment,and the strengthening phasesγ′andγ″further precipitate.However,the precipitation phases dissolve significantly in the Weld Zone(WZ)due to the thermal process of LFW.The corrosion resistance in BM is reduced after the pre-weld heat treatment,while it is similar in WZ with a slight decrease.The surface morphology of the BM and WZ can be generally divided into a loose and porous matrix and a scattered oxide particle layer after hot corrosion.The joint cross section exhibits a Cr-depleted zone with the diffusion of Cr to form an oxide film.The corrosion product mainly consists of Fe_(2)O_(3)/Fe_(3)O_(4) as the outer layer and Cr_(2)O_(3) as the inner layer. 展开更多
关键词 Linear friction weldingi GH4169 superalloy Heat treatment Mechanical properties Corrosion behavior
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Undrained mechanical behavior of unsaturated completely weathered granite:Experimental investigation and constitutive modeling 被引量:1
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作者 DU Shao-hua MA Jin-yin +2 位作者 RUAN Bo WU Gen-shui ZHANG Rui-chao 《Journal of Central South University》 2025年第6期2307-2327,共21页
The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique natu... The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique nature of this soil type.In this study,a series of unconfined compression tests were carried out on unsaturated CWG soil in an underground engineering site,and the effects of varying the environmental variables on the main undrained mechanical properties were analyzed.Based on the experimental results,a novel constitutive model was then established using the damage mechanics theory and the undetermined coefficient method.The results demonstrate that the curves of remolded CWG specimens with different moisture contents and dry densities exhibited diverse characteristics,including brittleness,significant softening,and ductility.As a typical indicator,the unconfined compression strength of soil specimens initially increased with an increase in moisture content and then decreased.Meanwhile,an optimal moisture content of approximately 10.5%could be observed,while a critical moisture content value of 13.0%was identified,beyond which the strength of the specimen decreases sharply.Moreover,the deformation and fracture of CWG specimens were predominantly caused by shear failure,and the ultimate failure modes were primarily influenced by moisture content rather than dry density.Furthermore,by comparing several similar models and the experimental data,the proposed model could accurately replicate the undrained mechanical characteristics of unsaturated CWG soil,and quantitatively describe the key mechanical indexes.These findings offer a valuable reference point for understanding the underlying mechanisms,anticipating potential risks,and implementing effective control measures in similar underground engineering projects. 展开更多
关键词 completely weathered granite undrained mechanical behavior environmental variable unconfined compression test constitutive model
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Impact behavior and strain rate effects of artificial limestone by MICP 被引量:1
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作者 Yaru Lv Lin Wu +2 位作者 Zhigang Duan Yuchen Su Dongdong Zhang 《Biogeotechnics》 2025年第2期72-80,共9页
Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an... Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an artificial method in a laboratory setting using microbial-induced carbonate precipitation(MICP)to simulate the natural process of cementation of limestone.The artificially cemented sand has a high degree of similarity with the natural weakly limestone in three aspects:(1)the mineral composition of the cemented material is also granular calcite and acicular aragonite;(2)the microstructure in interconnected open pore network can be gradually closed and contracted with cementation.The porosity reaches to approximately 9.2%;(3)both the stress-strain relationship and the unconfined strength closely resemble that of natural weakly limestone.Furthermore,both static and dynamic behaviors of artificial limestone were studied by quasi-static compression tests and Split Hopkinson Pressure Bar(SHPB)tests,finding that the unconfined strength of weakly artifical limestone exponentially increases with increasing strain rate.A rate-dependent bond strength was proposed and implemented in software to reveal the mechanism of strain rate effects.It is found that the loading velocity is too high to keep in sync with the initiation and propagation of cracks under impact loading.This delay-induced viscosity may restrict the movement of the surrounding balls,thus increasing resistance. 展开更多
关键词 Weakly limestone MICP artificial cementation Calcareous sand Limestone impact behavior Strain rate effects
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Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels
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作者 Yumeng Wang Qinyi Guo +1 位作者 Bin Hu Haiwen Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期360-368,共9页
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulati... The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow instability.We concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present. 展开更多
关键词 medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability
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Commentary on“Accelerometer-measured physical activity,sedentary behavior,and incidence of macrovascular and microvascular events in individuals with type 2 diabetes mellitus and prediabetes” 被引量:1
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作者 Barbara E.Ainsworth Haili Tian 《Journal of Sport and Health Science》 2025年第1期3-5,共3页
Type 2 diabetes(T2D)is an insidious disease associated with neural and vascular complications,acceleration of cardiovascular disease,changes in heart function,and premature death.In the newly released article of the J... Type 2 diabetes(T2D)is an insidious disease associated with neural and vascular complications,acceleration of cardiovascular disease,changes in heart function,and premature death.In the newly released article of the Journal of Sport and Health Science,Liang et al.1 describe results from the UK Biobank data showing the benefits of moderate-to-vigorous intensity physical activity(MVPA)on reducing the risks for vascular events in 11,474 adults with T2D and prediabetes. 展开更多
关键词 PREDIABETES type diabetes t d sedentary behavior vascular events macrovascular events type diabetes mellitus microvascular events
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The wearable landscape: Issues pertaining to the validation of the measurement of 24-h physical activity, sedentary, and sleep behavior assessment 被引量:2
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作者 Marco Giurgiu Birte von Haaren-Mack +16 位作者 Janis Fiedler Simon Woll Alexander Burchartz Simon Kolb Sascha Ketelhut Claudia Kubica Carina Nigg Irina Timm Maximiliane Thron Steffen Schmidt Kathrin Wunsch Gerhard Muller Claudio RNigg Alexander Woll Markus Reichert Ulrich Ebner-Priemer Johannes BJ Bussmann 《Journal of Sport and Health Science》 2025年第3期131-139,共9页
The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activit... The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activity, sedentary habits, sleep patterns) within the 24-h cycle of daily life. Wearables are applied in research, clinical practice, and as lifestyle devices;most obvious, they promise to be a key element for increasing human physical activity, one of the biggest health challenges nowadays. 展开更多
关键词 increasing human physical activityone lifestyle devicesmost validation studies health behaviorwearable technology revolution information technology wearable technology physical activity physical behaviors iephysical
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An effective stress-based DSC model for predicting hydromechanical shear behavior of unsaturated collapsible soils subjected to initial shear stress 被引量:1
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作者 Saman Soleymani Borujerdi S.Mohsen Haeri +1 位作者 Amir Akbari Garakani Chandrakant SDesai 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期539-555,共17页
Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have en... Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results. 展开更多
关键词 Unsaturated collapsible soil Initial shear stress Hydromechanical shear behavior Effective stress Disturbed state concept Critical state
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Effect of Saccharin on Crystallization Behavior of Electroless Cobalt Plating
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作者 Yu-Xin Luo Jing-Jing Wang +5 位作者 Lu Wang Zi-Yi Yan Yi Ma Xin Bo Jing-Shuang Dang Zeng-Lin Wang 《电化学(中英文)》 北大核心 2025年第8期23-33,共11页
In the process of electroless cobalt plating,the saccharin additive can significantly change the surface morphology,texture orientation,and conductivity of the cobalt coating layer.When the amount of saccharin was 3 m... In the process of electroless cobalt plating,the saccharin additive can significantly change the surface morphology,texture orientation,and conductivity of the cobalt coating layer.When the amount of saccharin was 3 mg·L^(-1),the cobalt coating transformed from disordered large grains to a honeycomb structure,with a preferred orientation of(002)facet on hexago-nal close-packed(HCP)cobalt crystals.The resistivity of the cobalt film decreased to 14.4μΩ·cm,and further decreased to 10.7μΩ·cm after the annealing treatment.When the concentration of saccharin was increased,the grain size was gradually refined and a“stone forest”structure was observed,with the preferred orientation remaining unchanged.The addition of saccharin also slightly improves the purity of cobalt coating to a certain extent.Through the study of the crystallization behavior of cobalt electroless plating,saccharin molecules can adsorb to specific c-sites on the cobalt dense crystal plane,inhibiting the growth of abc stacking arrangement and inducing the crystal growth in ab stacking mode,thereby achieving optimal growth of HCP(002)texture. 展开更多
关键词 Electroless cobalt plating ADDITIVES SACCHARIN Crystallization behavior
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The work hardening and softening behavior of spherical Ti_(p)/Mg-5Zn-0.3Ca composite 被引量:1
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作者 Cui-ju Wang Jin-Kai Zhang +2 位作者 Kai-bo Nie Chao Xu Kun-kun Deng 《Journal of Magnesium and Alloys》 2025年第6期2752-2768,共17页
To obtain the Ti_(p)with different aspect ratios,the Ti_(p)/Mg-5Zn-0.3Ca composite prepared by semi-solid stir casting was subjected to extrusion at 220℃,180℃,and 140℃,respectively.Then,the effect of the Ti_(p)’s ... To obtain the Ti_(p)with different aspect ratios,the Ti_(p)/Mg-5Zn-0.3Ca composite prepared by semi-solid stir casting was subjected to extrusion at 220℃,180℃,and 140℃,respectively.Then,the effect of the Ti_(p)’s aspect ratio on the microstructure,mechanical properties,work hardening and softening behaviors of Ti_(p)/Mg-5Zn-0.3Ca composites was investigated.The results indicated that the Ti_(p)could be elongated obviously after low-temperature extrusion,and the aspect ratio of which would reach to 13.7:1 as the extrusion temperature deceased to 140℃.Then the“Ti/Mg”layer-like structure was formed in the Ti_(p)/Mg-5Zn-0.3Ca composite.Accompanied with the elongation of Ti_(p),the dynamic recrystallized grains and dynamic precipitates were both refined significantly,however,the dynamic recrystallization rate changed a little.The elongated Ti_(p)endowed the Ti_(p)/Mg-5Zn-0.3Ca composites with better matching of strength and toughness without the sacrifice of elongation and bending strain.Both the work hardening rate and softening rate of Ti_(p)/Mg-5Zn-0.3Ca composites increased with the increasing aspect ratio of Ti_(p).The formation of“Ti/Mg”layer-like structure contributed to the redistribution of strain from large aggregations to a network-like distribution,which effectively suppresses the initiation and propagation of micro-cracks,thus enhancing the plasticity of the Ti_(p)/Mg-5Zn-0.3Ca composites. 展开更多
关键词 Ti_(p) Particle reinforced magnesium matrix composites Work hardening and softening behavior Laminar-like configuration
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