Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and anxiety.Aims We investigated the association between positive and negativ...Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and anxiety.Aims We investigated the association between positive and negative stress events during different stages of pregnancy and postpartum mental health outcomes among low-income pregnant women with symptoms of anxiety in Pakistan and evaluated whether an intervention based on cognitive behavioural therapy(CBT)had a regulatory effect.Methods Participants were 621 pregnant Pakistani women with mild anxiety.Using the Pregnancy Experience Scale-Brief Version,six scores were created to assess positive and negative stressors.We performed a multivariate linear regression to examine whether these six scores,measured both at baseline and in the third trimester,were associated with postpartum anxiety and depressive symptoms.The effect of the intervention on this relationship was examined by adding an interaction term to the regression model.Results Hassles frequency measured in the third trimester was positively associated with depression(B=0.22,95%confidence interval(Cl):0.09 to 0.36)and anxiety(B=0.19,95%Cl:0.08to 0.30).At the same timepoint,uplifts intensity was negatively associated with symptoms of depression(B=-0.82,95%Cl:1.46 to-0.18)and anxiety(B=-0.70,95%Cl:-1.25 to-0.15),whereas hassles intensity was positively related to symptoms of depression(B=1.02,95%Cl:0.36 to 1.67)and anxiety(B=0.90,95%Cl:0.34 to 1.47).The intensity ratio of hassles to uplifts reported in the third trimester was positively related to both depression(B=1.40,95%Cl:0.59 to 2.20)and anxiety(B=1.26,95%Cl:0.57 to 1.96).The intervention strengthened the overall positive effects of uplfts and the negative effects of hassles.Pregnancy experiences at baseline during early pregnancy to mid-pregnancy were not associated with mental health outcomes.Conclusions Stressors in the third trimester but not earlier in pregnancy were associated with postpartum symptoms of anxiety and depression.The CBT intervention modified the association between pregnancy stressors and postpartum mental health outcomes.Programmes that promote positive experiences and reduce negative experiences,especially in late pregnancy,may mitigate postpartum mental health consequences.展开更多
Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment ...Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment.However,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research.For this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment behaviours.Significantly,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention measures.The various types of SGMs are depicted,and their ongoing developments and applications are explored in depth.The review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods.This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods.展开更多
Background The presence of mental health conditions is pervasive in patients who experienced acute myocardial infarction(AMI),significantly disrupting their recovery.Providing timely and easily accessible psychologica...Background The presence of mental health conditions is pervasive in patients who experienced acute myocardial infarction(AMI),significantly disrupting their recovery.Providing timely and easily accessible psychological interventions using virtual reality-based cognitive-behavioural therapy(VR-CBT)could potentially improve both acute and long-term symptoms affecting their mental health.Aims We aim to examine the effectiveness of VR-CBT on anxiety symptoms in patients with AMI who were admitted to the intensive care unit(ICU)during the acute stage of their illness.Methods In this single-blind randomised clinical trial,participants with anxiety symptoms who were admitted to the ICU due to AMI were continuously recruited from December 2022 to February 2023.Patients who were Han Chinese aged 18-75 years were randomly assigned(1:1)via block randomisation to either the VR-CBT group to receive VR-CBT in addition to standard mental health support,or the control group to receive standard mental health support only.VR-CBT consisted of four modules and was delivered at the bedside over a 1-week period.Assessments were done at baseline,immediately after treatment and at 3-month follow-up.The intention-to-treat analysis began in June 2023.The primary outcome measure was the changes in anxiety symptoms as assessed by the Hamilton Anxiety Rating Scale(HAM-A).Results Among 148 randomised participants,70 were assigned to the VR-CBT group and 78 to the control group.The 1-week VR-CBT intervention plus standard mental health support significantly reduced the anxiety symptoms compared with standard mental health support alone in terms of HAM-A scores at both post intervention(Cohen’s d=−1.27(95%confidence interval(CI):−1.64 to−0.90,p<0.001)and 3-month follow-up(Cohen’s d=−0.37(95%CI:−0.72 to−0.01,p=0.024).Of the 70 participants who received VR-CBT,62(88.6%)completed the entire intervention.Cybersickness was the main reported adverse event(n=5).Conclusions Our results indicate that VR-CBT can significantly reduce post-AMI anxiety at the acute stage of the illness;the improvement was maintained at the 3-month follow-up.Trial registration number The trial was registered at www.chictr.org.cn with the identifier:ChiCTR2200066435.展开更多
Background: Adolescents in developing countries have limited knowledge about the prevention of STIs and unwanted pregnancies. In several African countries, risky sexual behaviour persists, including early sexual debut...Background: Adolescents in developing countries have limited knowledge about the prevention of STIs and unwanted pregnancies. In several African countries, risky sexual behaviour persists, including early sexual debut, multiple sexual partners, economic and sexual exchange, and low condom and contraceptive use. The purpose of this study is to assess the sexual and reproductive health knowledge and behaviour of adolescents in rural Burkina Faso in order to improve their sexual and reproductive health. Method: This was a descriptive cross-sectional study with prospective data collection conducted from 07 March to 04 April 2022 in the area of the Demographic and Health Surveillance System of the Nouna Research Centre. A questionnaire was administered to a randomly selected sample of 1202 adolescents. Results: The mean age of the adolescents was 14.1 years and 56.6% were male. Only 58.2% of the adolescents had ever heard of HIV/AIDS. Of these, 95.7% did not know their HIV status. In addition, 15.8% had ever had sexual intercourse and 2.4% had been sexually active at an early age. Almost 45% had not used any contraceptive method the last time they had sex. Condoms were the most frequently used contraceptive method (47.4%). Among teenagers, 27.6% had been pregnant at least once, 7.3% were married and the average age at marriage was 18.45 years. Almost 7% (6.9%) of teenagers had more than one sexual partner. Conclusion: Adolescents have limited knowledge about reproductive health. Risky sexual behaviour persists. Awareness campaigns need to be intensified to improve their sexual and reproductive health.展开更多
The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal mines.Therefore,H-M coupling tests of be...The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal mines.Therefore,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were conducted.Then,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were obtained.Subsequently,the mechanical behaviour was characterized,and finally the failure mechanism was revealed.The results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak strength.However,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear failure.When the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping failure.When the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear failure.The above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.展开更多
Constructing the magnesium alloy with fine grains,low density of dislocations,and weak crystal orientation is of crucial importance to enhance its comprehensive performance as the anode for Mg-air battery.However,this...Constructing the magnesium alloy with fine grains,low density of dislocations,and weak crystal orientation is of crucial importance to enhance its comprehensive performance as the anode for Mg-air battery.However,this unique microstructure can hardly be achieved with conventional plastic deformation such as rolling or extrusion.Herein,we tailor the microstructure of Mg-Al-Sn-RE alloy by using the friction stir processing,which obviously refines the grains without increasing dislocation density or strengthening crystal orientation.The Mg-air battery with the processed Mg-Al-Sn-RE alloy as the anode exhibits higher discharge voltages and capacities than that employing the untreated anode.Furthermore,the impact of friction stir processing on the electrochemical discharge behaviour of Mg-Al-Sn-RE anode and the corresponding mechanism are also analysed according to microstructure characterization and electrochemical response.展开更多
Objective:To investigate the interrelationship between cardiovascular health awareness,risk perception,behavioural intention,and INTERHEART risk stratification in a middle-aged adult population in Malaysia.Methods:A c...Objective:To investigate the interrelationship between cardiovascular health awareness,risk perception,behavioural intention,and INTERHEART risk stratification in a middle-aged adult population in Malaysia.Methods:A cross-sectional survey with convenience sampling was conducted during November 2022 and January 2023.Participants completed validated questionnaires assessing cardiovascular health awareness,risk perception of cardiovascular diseases,behavioural intention towards adopting healthy habits,and INTERHEART risk stratification score(IHRS)based on established risk factors.A total of 602 respondents were included in the final analysis.Data were analysed with independent t-test/one-way ANOVA or Mann-Whitney/Kruskal-Wallis to test the differences,Pearson correlation or linear regression test to analyze the association of independent and dependent variables.Results:There was a significant positive correlation between medical knowledge related to cardiovascular disease(CVD)and knowledge related to CVD risk prevention,risk perception,behavioural intention and IHRS(P<0.05,Pearson correlation).Notably,individuals with higher IHRS tended to have lower knowledge related to CVD and CVD risk prevention,risk perception,and behavioural intention.Males,laborers,active/former smokers,individuals with lower household income and educational levels,those involved in occupations not related to the healthcare sector,and those who did not receive the CVD health brochure or are unaware of health self-assessment tools are likely to have lower levels of knowledge,risk perception,and poorer behavioural intention regarding cardiovascular health(P<0.05,one-way ANOVA).While educational level,smoking status,awareness about CVD poster,self-assessment tools were repeatedly significantly associated with knowledge related to CVD and CVD risk prevention,risk perception,behavioral intention and/or IHRS(P<0.05,linear regression).Conclusions:These findings underscore the importance of promoting cardiovascular health awareness and risk perception among middle-aged adults to foster positive BI and reduce CVD risk.Tailored interventions targeting specific risk factors identified by INTERHEART may enhance risk stratification accuracy and facilitate targeted preventive strategies.展开更多
Green spaces in urban and suburban areas play a significant role in helping settlements adapt to climate change.The design,quantity,quality,and location of green spaces influence their ability to provide benefits to p...Green spaces in urban and suburban areas play a significant role in helping settlements adapt to climate change.The design,quantity,quality,and location of green spaces influence their ability to provide benefits to people and enhance the quality of life.Private green spaces,if adequately managed,can enhance the environmental quality.This study,based on a questionnaire survey and the Motivation/Attitude-Driven Behaviour(MADB)model,investigated how the attitudes and behaviours of residents shape private green spaces in 12 settlements of the 4 city regions(Cluj region,Nitra region,Kecskemét region,and Györ region)in 3 Central European countries(Hungary,Slovakia,and Romania).The results showed that beautiful natural environment,abundance of green spaces,beautiful settlement and streetscape,and village atmosphere were mentioned most often,along with good quality of life,with a mention rate of over 70.00%in the four city regions.Convenience also played a significant role in the management of green spaces,showing that convenience factors(less work,less waste,and cheaper management)more important for those who live in settlements nearer to the cities.The importance of biodiversity and ecology was positively correlated with socio-economic status such as education and financial situation.However,the importance of the utility of green spaces was less prevalent among original villagers and settlers.Moreover,we found that the percentage of green spaces of settlers is slightly higher than that of original villagers.The results of factor analysis revealed that socio-economic status can influence respondents’attitudes towards green spaces.It suggests to increase ecological awareness of residents,especially for new settlers,and promote good management techniques for green spaces.This study can improve the awareness of urban planners about the importance of green spaces in suburban areas.展开更多
The cashew stem girdler, Analeptes trifasciata Fabricius (Coleoptera: Cerambycidae), damages cashew by its girdling activities in the stem thereby causing huge economic losses. The stem girdler is managed through cult...The cashew stem girdler, Analeptes trifasciata Fabricius (Coleoptera: Cerambycidae), damages cashew by its girdling activities in the stem thereby causing huge economic losses. The stem girdler is managed through cultural practice of burning girdled stems and beetles, though this has drawbacks. The objective of this study was to explore the cues mediating attraction to the cashew host plant;hence the role of olfaction in host plant location by A. trifasciata underlying the semio-chemical option for controlling this insect pest. A diffusional Y-tube olfactometer was used to study the behavioural response of A. trifasciata, to freshly cut cashew stem and leaves odour sources. Methanol-extract of these plant tissues was subjected to the coupled gas chromatography-mass spectrometry (GC-MS) analysis. Y-tube olfactometric assays demonstrated that both sexes oriented towards and spent significantly more time in stem odour arm compared to the leaf odour arm in both male (male: t = 2.228, d.f = 11, P = 0.040) and female (t = 2.341, d.f = 11, P = 0.040). A combination of fatty acids, amino acids and carbohydrates were detected in cashew stems. Some of these fatty acids are attractants to other insect pests. It is suspected that these fatty acid blends may possibly be responsible for facilitating host plant location by both sexes. In conclusion, both sexes were independently and strongly attracted to the stem volatiles;this study opens the possibility of utilizing cashew stem volatiles as surveillance and control tools.展开更多
The paper presents the analysis of a human evacuation from a higher education building located in Iassy,Romania,by means of engineering techniques to approach fire safety.Because in Romania(as in other European countr...The paper presents the analysis of a human evacuation from a higher education building located in Iassy,Romania,by means of engineering techniques to approach fire safety.Because in Romania(as in other European countries)fire safety design of buildings is prescriptive and not performance-based,a fire safety engineering approach arouse great interest in many countries such as the U.S.A.,Australia,New Zealand,England,Sweden,Finland,etc.This paper is based on the assumption of starting a fire in the space of a hall for festivities,located on the ground floor of the building,near two human evacuation routes;We consider two building evacuation scenarios:two exits and,respectively,just one exit(assuming that the second would be accidentally blocked).展开更多
This paper aims to explore how a veteran teacher organizes online teaching initiated by the pandemic and how she deals with the problems in online teacher-student verbal interaction.By analyzing a corpus of 20 audio-r...This paper aims to explore how a veteran teacher organizes online teaching initiated by the pandemic and how she deals with the problems in online teacher-student verbal interaction.By analyzing a corpus of 20 audio-recorded online lessons between a math teacher and her students during the COVID-19 pandemic from April 11 to May 10,2022,four interactional segments are selected as the focus of the study.The results of the conversation analysis of the segments showed that students’modesty,lack of confidence,lack of ability,and network delay are the main factors affecting online teacher-student interaction.By encouraging students to answer questions,enlightening students to give answers,enriching students’answers,and entertaining the teaching atmosphere(“4Es”strategies),the teacher solved the problems successfully.The findings from this study can provide pedagogical experience and implications for practical teaching.展开更多
A series of multi-hydroxyl bis-(quaternary ammonium)ionic liquids(Ils1‒7)was prepared as bifunctional catalysts for the chemical fixation of CO_(2).All these ionic liquid compounds were efficient for the catalytic syn...A series of multi-hydroxyl bis-(quaternary ammonium)ionic liquids(Ils1‒7)was prepared as bifunctional catalysts for the chemical fixation of CO_(2).All these ionic liquid compounds were efficient for the catalytic synthesis of cyclic carbonates and oxazolidinones via the cycloaddition reactions between CO_(2) and epoxides or aziridines with excellent yield and high selectivity in the absence of co-catalyst,metal and solvent.Due to the synergistic effects of hydroxyl groups and halogen anion,the cycloaddition reactions proceeded smoothly either at atmospheric pressure or room temperature.The selectivity for substituted oxazolidinones at 5-and 4-positions can be tuned via changing the reaction conditions.Finally,possible mechanisms including the activation of both CO_(2) and epoxide or aziridines were proposed based on the literatures and experimental results.展开更多
The reaction behaviours of A1203 and SiO2 in high alumina coal fly ash under various alkali hydrothermal conditions were studied. The means of XRD, XRF, FTIR and SEM were used to measure the mineral phase and morpholo...The reaction behaviours of A1203 and SiO2 in high alumina coal fly ash under various alkali hydrothermal conditions were studied. The means of XRD, XRF, FTIR and SEM were used to measure the mineral phase and morphology of the solid samples obtained by different alkali hydrothermal treatments as well as the leaching ratio of SiO2 to A1203 in alkali solution. The results showed that with the increase of the hydrothermal treating temperature from 75 to 160 ~C, phillipsite-Na, zeolite A, zeolite P, and hydroxysodalite were produced sequentially while the mullite and corundum phase still remained. Zeolite P was massively formed at low-alkali concentration and the hydroxysodalite was predominantly obtained at high-alkali concentration. By the dissolution of aluminosilicate glass and the formation of zeolites together, the leaching efficiency of SiO2 can reach 42.13% with the mass ratio of A1203/SIO2 up to 2.19:1.展开更多
Porous titanium has been shown to exhibit desirable properties as biomedical materials. In view of the load-bearing situation, the mechanical properties and pore structure deformation behaviour of porous titanium were...Porous titanium has been shown to exhibit desirable properties as biomedical materials. In view of the load-bearing situation, the mechanical properties and pore structure deformation behaviour of porous titanium were studied. Porous titanium with porosities varying from 36%-66% and average pore size of 230 μm was fabricated by powder sintering. Microstructural features were characterized using scanning electron microscopy. Uniaxial compression tests were used to probe the mechanical response in terms of elastic modulus and compressive strength. The mechanical properties of porous titanium were found to be close to the those of human bone, with stiffness values ranging from 1.86 to 14.7 GPa and compressive strength values of 85.16-461.94 MPa. The relationships between mechanical properties and relative densities were established, and the increase in relative density showed significant effects on mechanical properties and deformations of porous titanium. In a lower relative density, the microscopic deformation mechanism of porous titanium was yielding, bending and buckling of cell walls, while the deformation of yielding and bending of cell walls was observed in the porous titanium with higher relative density.展开更多
The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay ...The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy (EIS) analysis.展开更多
Ecological reactive powder concrete (ECO-RPC) with small sized and differentvolume fraction steel fibers was prepared by substitution of ultra-fine industrial waste powder for50% to 60% cement by weight and replacemen...Ecological reactive powder concrete (ECO-RPC) with small sized and differentvolume fraction steel fibers was prepared by substitution of ultra-fine industrial waste powder for50% to 60% cement by weight and replacement of ground fine quartz sand with natural fine aggregate.The effect of steel fiber volume fraction and curing ages on the static mechanical behaviour ofECO-RPC was studied. Using the split Hopkinson pressure bar technique, the dynamic mechanicalbehaviour of ECO-RPC was investigated under different strain rates. The results show that the staticmechanical behaviour of ECO-RPC increases with the increase of steel fiber volume fraction andcuring ages. The type of ECO-RPC with the substitution of 25% ultra-fine slag, 25% ultra-fine flyash and 10% silica fume is better than the others with compressive strength, flexural strength, andfracture energy more than 200 MPa, 60 MPa and 30 kJ/m^2, respectively. ECO-RPC has excellent strainrate stiffening effects under dynamic load. Its peak stress, peak strain and the area understrain-stress curve increase with the increase of strain rate. Its fracture pattern changes frombrittleness to toughness under high strain rates.展开更多
To cope with multi-object tracking under real-world complex situations, a new video-based method is proposed. In the detecting step, the moving objects are segmented with the third level DWT (discrete wavelet transfo...To cope with multi-object tracking under real-world complex situations, a new video-based method is proposed. In the detecting step, the moving objects are segmented with the third level DWT (discrete wavelet transform )and background difference. In the tracking step, the Kalman filter and scale parameter are used first to estimate the object position and bounding box. Then, the center-association-based projection ratio and region-association-based occlusion ratio are defined and combined to judge object behaviours. Finally, the tracking scheme and Kalman parameters are adaptively adjusted according to object behaviour. Under occlusion, partial observability is utilized to obtain the object measurements and optimum box dimensions. This method is robust in tracking mobile objects under such situations as occlusion, new appearing and stablization, etc. Experimental results show that the proposed method is efficient.展开更多
Implicature is a universal feature of human communication.In conversations,it is common to see examples of something unsaid but communicated.After introducing the theory of conversational impilcature and its four maxi...Implicature is a universal feature of human communication.In conversations,it is common to see examples of something unsaid but communicated.After introducing the theory of conversational impilcature and its four maxims,this paper presents English and Chinese examples to compare their conversational implicature,and finds conversational implicature exists in both Chinese and English conversation.展开更多
Cultural values determine and influence the communicative competence in a substantial way.Conversational styles are also demonstrated by cultural values which are obvious to be discovered in any cultures.The paper is ...Cultural values determine and influence the communicative competence in a substantial way.Conversational styles are also demonstrated by cultural values which are obvious to be discovered in any cultures.The paper is aimed at making a brief analysis of differences between Chinese and English from the perspective of the intercultural communication for the promotion of language abilities for learners during the cultural exchanges.展开更多
This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it ...This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it reveals how the different purposes of speech result in their distinctive characteristics, and shows how language is struc- tured to construct ideational meanings(Field) and interpersonal meanings(Tenor) that define each context.展开更多
基金the National Institute of Mental Health at the US National Institutes of Health(grant number:R01 MH111859).
文摘Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and anxiety.Aims We investigated the association between positive and negative stress events during different stages of pregnancy and postpartum mental health outcomes among low-income pregnant women with symptoms of anxiety in Pakistan and evaluated whether an intervention based on cognitive behavioural therapy(CBT)had a regulatory effect.Methods Participants were 621 pregnant Pakistani women with mild anxiety.Using the Pregnancy Experience Scale-Brief Version,six scores were created to assess positive and negative stressors.We performed a multivariate linear regression to examine whether these six scores,measured both at baseline and in the third trimester,were associated with postpartum anxiety and depressive symptoms.The effect of the intervention on this relationship was examined by adding an interaction term to the regression model.Results Hassles frequency measured in the third trimester was positively associated with depression(B=0.22,95%confidence interval(Cl):0.09 to 0.36)and anxiety(B=0.19,95%Cl:0.08to 0.30).At the same timepoint,uplifts intensity was negatively associated with symptoms of depression(B=-0.82,95%Cl:1.46 to-0.18)and anxiety(B=-0.70,95%Cl:-1.25 to-0.15),whereas hassles intensity was positively related to symptoms of depression(B=1.02,95%Cl:0.36 to 1.67)and anxiety(B=0.90,95%Cl:0.34 to 1.47).The intensity ratio of hassles to uplifts reported in the third trimester was positively related to both depression(B=1.40,95%Cl:0.59 to 2.20)and anxiety(B=1.26,95%Cl:0.57 to 1.96).The intervention strengthened the overall positive effects of uplfts and the negative effects of hassles.Pregnancy experiences at baseline during early pregnancy to mid-pregnancy were not associated with mental health outcomes.Conclusions Stressors in the third trimester but not earlier in pregnancy were associated with postpartum symptoms of anxiety and depression.The CBT intervention modified the association between pregnancy stressors and postpartum mental health outcomes.Programmes that promote positive experiences and reduce negative experiences,especially in late pregnancy,may mitigate postpartum mental health consequences.
基金support from the National Natural Science Foundation of China (No.52172407 and No.U19A20110)the Natural Science Foundation of Sichuan Province (No.2022NSFSC0415).
文摘Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment.However,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research.For this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment behaviours.Significantly,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention measures.The various types of SGMs are depicted,and their ongoing developments and applications are explored in depth.The review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods.This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods.
基金The study was supported by the Transverse Project of Zhongshan Hospital and Hangzhou Xinjing Science and Technology(XH,H2022-009)National Key Research and Development Program of China(XH,2023YFC2506200)Shanghai Clinical Research Center for Interventional Medicine(JBG,19MC1910300).
文摘Background The presence of mental health conditions is pervasive in patients who experienced acute myocardial infarction(AMI),significantly disrupting their recovery.Providing timely and easily accessible psychological interventions using virtual reality-based cognitive-behavioural therapy(VR-CBT)could potentially improve both acute and long-term symptoms affecting their mental health.Aims We aim to examine the effectiveness of VR-CBT on anxiety symptoms in patients with AMI who were admitted to the intensive care unit(ICU)during the acute stage of their illness.Methods In this single-blind randomised clinical trial,participants with anxiety symptoms who were admitted to the ICU due to AMI were continuously recruited from December 2022 to February 2023.Patients who were Han Chinese aged 18-75 years were randomly assigned(1:1)via block randomisation to either the VR-CBT group to receive VR-CBT in addition to standard mental health support,or the control group to receive standard mental health support only.VR-CBT consisted of four modules and was delivered at the bedside over a 1-week period.Assessments were done at baseline,immediately after treatment and at 3-month follow-up.The intention-to-treat analysis began in June 2023.The primary outcome measure was the changes in anxiety symptoms as assessed by the Hamilton Anxiety Rating Scale(HAM-A).Results Among 148 randomised participants,70 were assigned to the VR-CBT group and 78 to the control group.The 1-week VR-CBT intervention plus standard mental health support significantly reduced the anxiety symptoms compared with standard mental health support alone in terms of HAM-A scores at both post intervention(Cohen’s d=−1.27(95%confidence interval(CI):−1.64 to−0.90,p<0.001)and 3-month follow-up(Cohen’s d=−0.37(95%CI:−0.72 to−0.01,p=0.024).Of the 70 participants who received VR-CBT,62(88.6%)completed the entire intervention.Cybersickness was the main reported adverse event(n=5).Conclusions Our results indicate that VR-CBT can significantly reduce post-AMI anxiety at the acute stage of the illness;the improvement was maintained at the 3-month follow-up.Trial registration number The trial was registered at www.chictr.org.cn with the identifier:ChiCTR2200066435.
文摘Background: Adolescents in developing countries have limited knowledge about the prevention of STIs and unwanted pregnancies. In several African countries, risky sexual behaviour persists, including early sexual debut, multiple sexual partners, economic and sexual exchange, and low condom and contraceptive use. The purpose of this study is to assess the sexual and reproductive health knowledge and behaviour of adolescents in rural Burkina Faso in order to improve their sexual and reproductive health. Method: This was a descriptive cross-sectional study with prospective data collection conducted from 07 March to 04 April 2022 in the area of the Demographic and Health Surveillance System of the Nouna Research Centre. A questionnaire was administered to a randomly selected sample of 1202 adolescents. Results: The mean age of the adolescents was 14.1 years and 56.6% were male. Only 58.2% of the adolescents had ever heard of HIV/AIDS. Of these, 95.7% did not know their HIV status. In addition, 15.8% had ever had sexual intercourse and 2.4% had been sexually active at an early age. Almost 45% had not used any contraceptive method the last time they had sex. Condoms were the most frequently used contraceptive method (47.4%). Among teenagers, 27.6% had been pregnant at least once, 7.3% were married and the average age at marriage was 18.45 years. Almost 7% (6.9%) of teenagers had more than one sexual partner. Conclusion: Adolescents have limited knowledge about reproductive health. Risky sexual behaviour persists. Awareness campaigns need to be intensified to improve their sexual and reproductive health.
基金supported by the National Natural Science Foundation of China(Grant Nos.52034009 and 51974319)the Yue Qi Distinguished Scholar Project(Grant No.2020JCB01).
文摘The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal mines.Therefore,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were conducted.Then,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were obtained.Subsequently,the mechanical behaviour was characterized,and finally the failure mechanism was revealed.The results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak strength.However,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear failure.When the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping failure.When the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear failure.The above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.
基金The Authors acknowledge the financial support of the National Nature Science Foundation of China(No.52171067)the Natural Science Foundation of Guangdong Province of China(No.2022A1515012366).
文摘Constructing the magnesium alloy with fine grains,low density of dislocations,and weak crystal orientation is of crucial importance to enhance its comprehensive performance as the anode for Mg-air battery.However,this unique microstructure can hardly be achieved with conventional plastic deformation such as rolling or extrusion.Herein,we tailor the microstructure of Mg-Al-Sn-RE alloy by using the friction stir processing,which obviously refines the grains without increasing dislocation density or strengthening crystal orientation.The Mg-air battery with the processed Mg-Al-Sn-RE alloy as the anode exhibits higher discharge voltages and capacities than that employing the untreated anode.Furthermore,the impact of friction stir processing on the electrochemical discharge behaviour of Mg-Al-Sn-RE anode and the corresponding mechanism are also analysed according to microstructure characterization and electrochemical response.
基金This work was supported by the Ministry of Higher Education(MOHE),Malaysia,through Fundamental Research Grant Scheme(FRGS/1/2022/SKK10/UTAR/02/1)Universiti Tunku Abdul Rahman,Malaysia,through UTAR-Research Grant(IPSR/RMC/UTARRF/2021-C2/L08)MBBS Community Health Project(2022/2023),UTAR.
文摘Objective:To investigate the interrelationship between cardiovascular health awareness,risk perception,behavioural intention,and INTERHEART risk stratification in a middle-aged adult population in Malaysia.Methods:A cross-sectional survey with convenience sampling was conducted during November 2022 and January 2023.Participants completed validated questionnaires assessing cardiovascular health awareness,risk perception of cardiovascular diseases,behavioural intention towards adopting healthy habits,and INTERHEART risk stratification score(IHRS)based on established risk factors.A total of 602 respondents were included in the final analysis.Data were analysed with independent t-test/one-way ANOVA or Mann-Whitney/Kruskal-Wallis to test the differences,Pearson correlation or linear regression test to analyze the association of independent and dependent variables.Results:There was a significant positive correlation between medical knowledge related to cardiovascular disease(CVD)and knowledge related to CVD risk prevention,risk perception,behavioural intention and IHRS(P<0.05,Pearson correlation).Notably,individuals with higher IHRS tended to have lower knowledge related to CVD and CVD risk prevention,risk perception,and behavioural intention.Males,laborers,active/former smokers,individuals with lower household income and educational levels,those involved in occupations not related to the healthcare sector,and those who did not receive the CVD health brochure or are unaware of health self-assessment tools are likely to have lower levels of knowledge,risk perception,and poorer behavioural intention regarding cardiovascular health(P<0.05,one-way ANOVA).While educational level,smoking status,awareness about CVD poster,self-assessment tools were repeatedly significantly associated with knowledge related to CVD and CVD risk prevention,risk perception,behavioral intention and/or IHRS(P<0.05,linear regression).Conclusions:These findings underscore the importance of promoting cardiovascular health awareness and risk perception among middle-aged adults to foster positive BI and reduce CVD risk.Tailored interventions targeting specific risk factors identified by INTERHEART may enhance risk stratification accuracy and facilitate targeted preventive strategies.
基金supported by the Hungarian National Research,Development and Innovation Fund(NKFI-6-K-128703).
文摘Green spaces in urban and suburban areas play a significant role in helping settlements adapt to climate change.The design,quantity,quality,and location of green spaces influence their ability to provide benefits to people and enhance the quality of life.Private green spaces,if adequately managed,can enhance the environmental quality.This study,based on a questionnaire survey and the Motivation/Attitude-Driven Behaviour(MADB)model,investigated how the attitudes and behaviours of residents shape private green spaces in 12 settlements of the 4 city regions(Cluj region,Nitra region,Kecskemét region,and Györ region)in 3 Central European countries(Hungary,Slovakia,and Romania).The results showed that beautiful natural environment,abundance of green spaces,beautiful settlement and streetscape,and village atmosphere were mentioned most often,along with good quality of life,with a mention rate of over 70.00%in the four city regions.Convenience also played a significant role in the management of green spaces,showing that convenience factors(less work,less waste,and cheaper management)more important for those who live in settlements nearer to the cities.The importance of biodiversity and ecology was positively correlated with socio-economic status such as education and financial situation.However,the importance of the utility of green spaces was less prevalent among original villagers and settlers.Moreover,we found that the percentage of green spaces of settlers is slightly higher than that of original villagers.The results of factor analysis revealed that socio-economic status can influence respondents’attitudes towards green spaces.It suggests to increase ecological awareness of residents,especially for new settlers,and promote good management techniques for green spaces.This study can improve the awareness of urban planners about the importance of green spaces in suburban areas.
文摘The cashew stem girdler, Analeptes trifasciata Fabricius (Coleoptera: Cerambycidae), damages cashew by its girdling activities in the stem thereby causing huge economic losses. The stem girdler is managed through cultural practice of burning girdled stems and beetles, though this has drawbacks. The objective of this study was to explore the cues mediating attraction to the cashew host plant;hence the role of olfaction in host plant location by A. trifasciata underlying the semio-chemical option for controlling this insect pest. A diffusional Y-tube olfactometer was used to study the behavioural response of A. trifasciata, to freshly cut cashew stem and leaves odour sources. Methanol-extract of these plant tissues was subjected to the coupled gas chromatography-mass spectrometry (GC-MS) analysis. Y-tube olfactometric assays demonstrated that both sexes oriented towards and spent significantly more time in stem odour arm compared to the leaf odour arm in both male (male: t = 2.228, d.f = 11, P = 0.040) and female (t = 2.341, d.f = 11, P = 0.040). A combination of fatty acids, amino acids and carbohydrates were detected in cashew stems. Some of these fatty acids are attractants to other insect pests. It is suspected that these fatty acid blends may possibly be responsible for facilitating host plant location by both sexes. In conclusion, both sexes were independently and strongly attracted to the stem volatiles;this study opens the possibility of utilizing cashew stem volatiles as surveillance and control tools.
文摘The paper presents the analysis of a human evacuation from a higher education building located in Iassy,Romania,by means of engineering techniques to approach fire safety.Because in Romania(as in other European countries)fire safety design of buildings is prescriptive and not performance-based,a fire safety engineering approach arouse great interest in many countries such as the U.S.A.,Australia,New Zealand,England,Sweden,Finland,etc.This paper is based on the assumption of starting a fire in the space of a hall for festivities,located on the ground floor of the building,near two human evacuation routes;We consider two building evacuation scenarios:two exits and,respectively,just one exit(assuming that the second would be accidentally blocked).
文摘This paper aims to explore how a veteran teacher organizes online teaching initiated by the pandemic and how she deals with the problems in online teacher-student verbal interaction.By analyzing a corpus of 20 audio-recorded online lessons between a math teacher and her students during the COVID-19 pandemic from April 11 to May 10,2022,four interactional segments are selected as the focus of the study.The results of the conversation analysis of the segments showed that students’modesty,lack of confidence,lack of ability,and network delay are the main factors affecting online teacher-student interaction.By encouraging students to answer questions,enlightening students to give answers,enriching students’answers,and entertaining the teaching atmosphere(“4Es”strategies),the teacher solved the problems successfully.The findings from this study can provide pedagogical experience and implications for practical teaching.
文摘A series of multi-hydroxyl bis-(quaternary ammonium)ionic liquids(Ils1‒7)was prepared as bifunctional catalysts for the chemical fixation of CO_(2).All these ionic liquid compounds were efficient for the catalytic synthesis of cyclic carbonates and oxazolidinones via the cycloaddition reactions between CO_(2) and epoxides or aziridines with excellent yield and high selectivity in the absence of co-catalyst,metal and solvent.Due to the synergistic effects of hydroxyl groups and halogen anion,the cycloaddition reactions proceeded smoothly either at atmospheric pressure or room temperature.The selectivity for substituted oxazolidinones at 5-and 4-positions can be tuned via changing the reaction conditions.Finally,possible mechanisms including the activation of both CO_(2) and epoxide or aziridines were proposed based on the literatures and experimental results.
基金Project(2652014017) supported by the Fundamental Research Funds for the Central Universities,China
文摘The reaction behaviours of A1203 and SiO2 in high alumina coal fly ash under various alkali hydrothermal conditions were studied. The means of XRD, XRF, FTIR and SEM were used to measure the mineral phase and morphology of the solid samples obtained by different alkali hydrothermal treatments as well as the leaching ratio of SiO2 to A1203 in alkali solution. The results showed that with the increase of the hydrothermal treating temperature from 75 to 160 ~C, phillipsite-Na, zeolite A, zeolite P, and hydroxysodalite were produced sequentially while the mullite and corundum phase still remained. Zeolite P was massively formed at low-alkali concentration and the hydroxysodalite was predominantly obtained at high-alkali concentration. By the dissolution of aluminosilicate glass and the formation of zeolites together, the leaching efficiency of SiO2 can reach 42.13% with the mass ratio of A1203/SIO2 up to 2.19:1.
基金Project(2012CB619101)supported by the National Basic Research Program of China
文摘Porous titanium has been shown to exhibit desirable properties as biomedical materials. In view of the load-bearing situation, the mechanical properties and pore structure deformation behaviour of porous titanium were studied. Porous titanium with porosities varying from 36%-66% and average pore size of 230 μm was fabricated by powder sintering. Microstructural features were characterized using scanning electron microscopy. Uniaxial compression tests were used to probe the mechanical response in terms of elastic modulus and compressive strength. The mechanical properties of porous titanium were found to be close to the those of human bone, with stiffness values ranging from 1.86 to 14.7 GPa and compressive strength values of 85.16-461.94 MPa. The relationships between mechanical properties and relative densities were established, and the increase in relative density showed significant effects on mechanical properties and deformations of porous titanium. In a lower relative density, the microscopic deformation mechanism of porous titanium was yielding, bending and buckling of cell walls, while the deformation of yielding and bending of cell walls was observed in the porous titanium with higher relative density.
基金Project(RDCPJ346365-06)supported by the Natural Sciences and Engineering Research Council of CanadaProject(51208193)supported by the National Natural Science Foundation of ChinaProject(11jj6034)supported by the Hunan Provincial Natural Science Foundation
文摘The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy (EIS) analysis.
文摘Ecological reactive powder concrete (ECO-RPC) with small sized and differentvolume fraction steel fibers was prepared by substitution of ultra-fine industrial waste powder for50% to 60% cement by weight and replacement of ground fine quartz sand with natural fine aggregate.The effect of steel fiber volume fraction and curing ages on the static mechanical behaviour ofECO-RPC was studied. Using the split Hopkinson pressure bar technique, the dynamic mechanicalbehaviour of ECO-RPC was investigated under different strain rates. The results show that the staticmechanical behaviour of ECO-RPC increases with the increase of steel fiber volume fraction andcuring ages. The type of ECO-RPC with the substitution of 25% ultra-fine slag, 25% ultra-fine flyash and 10% silica fume is better than the others with compressive strength, flexural strength, andfracture energy more than 200 MPa, 60 MPa and 30 kJ/m^2, respectively. ECO-RPC has excellent strainrate stiffening effects under dynamic load. Its peak stress, peak strain and the area understrain-stress curve increase with the increase of strain rate. Its fracture pattern changes frombrittleness to toughness under high strain rates.
基金The National Natural Science Foundation of China(No.60574006,60804017)
文摘To cope with multi-object tracking under real-world complex situations, a new video-based method is proposed. In the detecting step, the moving objects are segmented with the third level DWT (discrete wavelet transform )and background difference. In the tracking step, the Kalman filter and scale parameter are used first to estimate the object position and bounding box. Then, the center-association-based projection ratio and region-association-based occlusion ratio are defined and combined to judge object behaviours. Finally, the tracking scheme and Kalman parameters are adaptively adjusted according to object behaviour. Under occlusion, partial observability is utilized to obtain the object measurements and optimum box dimensions. This method is robust in tracking mobile objects under such situations as occlusion, new appearing and stablization, etc. Experimental results show that the proposed method is efficient.
文摘Implicature is a universal feature of human communication.In conversations,it is common to see examples of something unsaid but communicated.After introducing the theory of conversational impilcature and its four maxims,this paper presents English and Chinese examples to compare their conversational implicature,and finds conversational implicature exists in both Chinese and English conversation.
文摘Cultural values determine and influence the communicative competence in a substantial way.Conversational styles are also demonstrated by cultural values which are obvious to be discovered in any cultures.The paper is aimed at making a brief analysis of differences between Chinese and English from the perspective of the intercultural communication for the promotion of language abilities for learners during the cultural exchanges.
文摘This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it reveals how the different purposes of speech result in their distinctive characteristics, and shows how language is struc- tured to construct ideational meanings(Field) and interpersonal meanings(Tenor) that define each context.