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The Relationship between Parental Marital Conflict and Adolescent Short Video Dependence:A Chain Mediation Model
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作者 Lei Yang Yang Liu 《International Journal of Mental Health Promotion》 2026年第1期168-186,共19页
Background:This study aims to investigate the underlying mechanisms between parental marital conflict and adolescent short video dependence by constructing a chain mediation model,focusing on the mediating roles of ex... Background:This study aims to investigate the underlying mechanisms between parental marital conflict and adolescent short video dependence by constructing a chain mediation model,focusing on the mediating roles of experiential avoidance and emotional disturbance(anxiety,depression,and stress).Methods:Conducted in January 2025,the research recruited 4125 adolescents from multiple Chinese provinces through convenience sampling;after data cleaning,3957 valid participants(1959 males,1998 females)were included.Using a cross-sectional design,measures included parental marital conflict,experiential avoidance,anxiety,depression,stress,and short video dependence.Results:Pearson correlation analysis revealed significant positive correlations among all variables.Mediation analysis using the SPSS PROCESS macro showed that parental marital conflict directly predicted short video dependence(β=0.269,p<0.001),and also significantly predicted experiential avoidance(β=0.519,p<0.001),anxiety(β=0.072,p<0.001),depression(β=0.067,p<0.001),and stress(β=0.048,p<0.05).Experiential avoidance further predicted anxiety(β=0.521,p<0.001),depression(β=0.489,p<0.001),stress(β=0.408,p<0.001),and short video dependence(β=0.244,p<0.001).While both anxiety(β=0.050,p<0.05)and depression(β=0.116,p<0.001)positively predicted short video dependence,stress did not(β=0.019,p=0.257).Overall,experiential avoidance,anxiety,depression,and stress significantly mediated the relationship between parental marital conflict and short video dependence.Conclusion:These findings confirm that parental marital conflict not only directly influences adolescent short video dependence but also operates through a chain mediation pathway involving experiential avoidance and emotional disturbance,highlighting central psychological mechanisms and providing theoretical support for integrated mental health and behavioral interventions. 展开更多
关键词 Parental marital conflict experiential avoidance ANXIETY depression stress emotional disturbance short video dependence
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Temperature dependence of two or more water species in delignified wood and lignocellulosic,tracked by LFNMR relaxometry
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作者 Long Zhou Wenjing Liu +5 位作者 Zhihong Zhao Rui Tan Xiaofeng Zhu Shen Wang Zonghai Harry Xie Minghui Zhang 《Magnetic Resonance Letters》 2026年第1期13-24,共12页
Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delig... Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delignified sapwood(DSW),delignified heartwood(DHW)and lignocellulose(LC)samples at different temperatures.Results indicate that below the freezing point of bulk water,free water freezes,causing its signal to disappear from the distribution.Then,the low temperature distributions of the unfrozen bound water contain more information about its components,with DSW,DHW and LC containing two distinct states of bound water(OH bound water(B-water)and more freely bound water(C-water)).Furthermore,it was observed that within the temperature range of−3°C to−60°C,B-water in DSW,DHW and LC maintained a higher unfrozen water content(UWC)value than C-water,and the T_(1)/T_(2)ratios for B-water were consistently higher than that for C-water,indicating that B-water has a greater antifreeze capacity.T_(2)and T_(1)distributions offer different kinds of information about water components,and all peaks within the distribution have been assigned. 展开更多
关键词 Low-field nuclear magnetic resonance (LFNMR) Delignified wood and lignocellulosic Water species Relaxation characteristics Bound water Temperature dependence
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Simultaneous removal of tetracycline and antibiotic resistant bacteria/genes in UV-LED/H_(2)O_(2) system:Competitive interactions and wavelength dependence
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作者 Jie Wang Jijie Zhang +7 位作者 Defang Ma Zhenxiang Sun Yan Wang Qinyan Yue Yanwei Li Yue Gao Baoyu Gao Xing Xu 《Chinese Chemical Letters》 2026年第2期655-661,共7页
The coexistence of emerging containments,such as antibiotic resistant bacteria(ARB),antibiotic-resistant genes(ARGs)and antibiotics,potentially influence elimination efficiencies in UV light-emitting diode(UV-LED)alon... The coexistence of emerging containments,such as antibiotic resistant bacteria(ARB),antibiotic-resistant genes(ARGs)and antibiotics,potentially influence elimination efficiencies in UV light-emitting diode(UV-LED)alone and UV-LED/H_(2)O_(2) system as their complex interactions.Tetracycline(TC)degradation efficiency(kF)correlated closely with its UV molar absorbance(R^(2)=0.831)in UV-LED alone system and with·OH yield(R^(2)=0.999)in UV-LED/H_(2)O_(2) system across studied wavelengths(265,280 and 310 nm).The kF values for intracellular DNA(i-ARGs)also exhibited a high correlation with UV-LED wavelengths in both systems(R^(2)=0.997-0.999).The coexistence of TC and ARB/ARGs resulted in a mutual inhibition of their degradation efficiencies due to competition for photons and·OH,along with the consequent reduction in intracellular ROS within ARB,with their degradation efficiencies exhibiting marked dependence on wavelength in both systems.Notably,the UV-LED/H_(2)O_(2) system at 265 nm effectively achieved the simultaneous removal of TC,ARB and ARGs with minimal energy consumption,and successfully fragmented ARGs.The degradation pathway of TC was analyzed,and the biotoxicity of its degradation intermediates demonstrated the environmental friendliness and safety of UV-LED/H_(2)O_(2) technology.This study elucidated the competitive interactions between antibiotics and ARB/ARGs within UV-LED/H_(2)O_(2) system,providing a promising approach for their simultaneous removal while ensuring energy efficiency. 展开更多
关键词 UV-LED/H_(2)O_(2) ARB/ARGs Wavelength dependence Competition Simultaneous removal
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Tobacco and other substance co-use among adolescents and young adults with cancer who use tobacco:prevalence and associations with nicotine dependence and depression
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作者 Elizabeth J Siembida Brittney Greene +4 位作者 Eun Jeong Oh Kara P Wiseman Melissa Basile Nehal P Vadhan Michael A Diefenbach 《Family Medicine and Community Health》 2025年第3期21-30,共10页
Introduction Tobacco and other substance co-use has not been examined in adolescent and young adult(AYA)cancer survivors.We compared the prevalence of past-month co-use of tobacco+cannabis,alcohol and illicit drugs be... Introduction Tobacco and other substance co-use has not been examined in adolescent and young adult(AYA)cancer survivors.We compared the prevalence of past-month co-use of tobacco+cannabis,alcohol and illicit drugs between AYAs with and without a cancer history and considered associations between co-use and nicotine dependence in AYA cancer survivors who use tobacco,exploring if past-year major depression moderates this relationship.Methods 2015–2019 National Survey on Drug Use and Health data were used to analyse past-month co-use in 7793 AYAs(228 with cancer;7565 without cancer).Weighted univariable and multivariable logistic regression models estimated associations between cancer history and co-use and co-use with nicotine dependence(among AYA cancer survivors)incorporating moderation by major depression.Results AYA cancer survivors had lower reported past-month cannabis co-use than those without cancer(29%vs 39%),but cancer history was not associated with cannabis co-use in multivariable models(adjusted OR(aOR):0.83,95%CI=0.54,1.28).When AYA cancer survivors who use tobacco had major depression,alcohol co-use was associated with lower rates of nicotine dependence(aOR=0.08,95%CI=0.01,0.53).Conclusions There are high rates of substance co-use among AYAs who use tobacco,consistent across cancer history.Unlike previous research,alcohol co-use was associated with lower rates of nicotine dependence,but only for those with major depression.This finding could be related to neurochemical dysregulation due to co-use and warrants further exploration.Future research should also examine more nuanced definitions of substance use including modes,patterns and initiation of use,and explore motivation to change tobacco behaviour in AYA cancer survivor populations. 展开更多
关键词 illicit drugs DEPRESSION health data nicotine dependence cancer survivors adolescents young adults tobacco use substance co use
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Surface element design of nanomaterials considering surface curvature dependence
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作者 Yongchao Zhang Lian Wang +2 位作者 Fangxin Wang Bin Li Xiaofan Gou 《Acta Mechanica Sinica》 2025年第1期42-53,共12页
Nanomaterials have garnered recognition for their notable surface effects and demonstration of superior mechanical properties.Previous studies on the surface effects of nanomaterials,employing the finite element metho... Nanomaterials have garnered recognition for their notable surface effects and demonstration of superior mechanical properties.Previous studies on the surface effects of nanomaterials,employing the finite element method,often relied on simplified twodimensional models due to theoretical complexities.Consequently,these simplified models inadequately represent the mechanical properties of nanomaterials and fail to capture the substantial impact of surface effects,particularly the curvature dependence of nanosurfaces.This study applies the principle of minimum energy and leverages the Steigmann-Ogden surface theory of nanomaterials to formulate a novel finite element surface element that comprehensively accounts for surface effects.We conducted an analysis of the stress distribution and deformation characteristics of four typical 2D and 3D nanomaterial models.The accuracy of the developed surface element and finite element calculation method was verified through comparison with established references.The resulting finite element model provides a robust and compelling scientific approach for accurately predicting the mechanical performance of nanomaterials. 展开更多
关键词 NANOMATERIALS Surface effect Surface element curvature dependence Finite element method
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Exploring the multiplicity dependence of the flavor hierarchy for hadron production in high-energy pp collisions
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作者 Ao-Gui Zhang Xin-Ye Peng Liang Zheng 《Nuclear Science and Techniques》 2025年第8期126-137,共12页
In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.T... In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.This study used a multi-phase transport(AMPT)model coupled with PYTHIA8 initial conditions.We investigated the baryon-to-meson and the strange-to-non-strange meson ratios varying with the charged particle density.By tuning the coalescence parameters,the AMPT model provides a reasonable description of the experimental data for the inclusive production of both light and charm hadrons,comparable to the string fragmentation model calculations with color reconnection effects.Additionally,we analyzed the relative production of hadrons by examining the self-normalized particle ratios as a function of the charged hadron density.Our findings suggest that parton evolution effects and the coalescence hadronization process in the AMPT model result in a strong flavor hierarchy in the multiplicity dependence of the baryon-to-meson ratio.Furthermore,our investigation of the p_(T) differential double ratio of the baryon-to-meson fraction between high-and low-multiplicity events revealed distinct modifications to the flavor associated baryon-to-meson ratio p_(T) shape in high-multiplicity events when comparing the coalescence hadronization model to the color reconnection model.These observations highlight the importance of understanding the hadronization process in high-energy pp collisions through comprehensive multiplicity-dependent multi-flavor analysis. 展开更多
关键词 Heavy flavor Multiplicity dependence Small system AMPT
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Temperature dependence of incomplete martensitic transformation and elastocaloric properties of superelastic NiTi:Experiment and phase-field simulation
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作者 Junyu Chen Qi Zhang +5 位作者 Boxin Wei Wenqiang Wang Wenjing Zhang Liping Lei Upadrasta Ramamurty Gang Fang 《Journal of Materials Science & Technology》 2025年第23期158-171,共14页
Partial phase transformation in NiTi-based refrigerants usually enables efficient and durable elastocaloric cooling,but its thermomechanical behavior with varying temperatures remains unclear.Keeping this in view,the ... Partial phase transformation in NiTi-based refrigerants usually enables efficient and durable elastocaloric cooling,but its thermomechanical behavior with varying temperatures remains unclear.Keeping this in view,the elastocaloric effect of NiTi under incomplete transformation across 15-100℃ is investigated and a superelastic deformation window between 25 and 85℃ is identified.Synchronous infrared thermography and digital image correlation,and an innovative macro-micro phase-field model are employed to examine martensitic transformation and elastocaloric properties of NiTi within the superelastic window.Experimental and simulated results consistently reveal that the spatiotemporal thermal profiles correlate with Lüders strain band evolution.As superelastic deformation temperature increases,strain localization intensifies,with Lüders bands favoring an inward strain growth over an outward expansion,resulting in a smaller yet more deformed martensitic transformation zone.The aggravated strain inhomogeneity makes the local endothermic undercooling tested at 85℃ up to about twice(−30.05℃)that at 25℃(−15.32℃),boosting the global cooling capacity by 65%,despite constant strain.The seeming contradiction between the larger elastocaloric effect and the narrower apparent martensitic transformation zone is elucidated by recourse to the simulations.It is found that the martensitic transformation within the Lüders bands is incomplete,proceeding in a macroscopically uniform but microscopically heterogeneous manner.Elevated temperatures within the superelastic window increase the transformed volume fraction and enhance martensitic transformation,thereby strengthening the global caloric effect.The work sheds light on the interplay between partial martensitic transformation and thermal behavior in NiTi under varying superelastic deformation temperatures,providing insights for advanced elastocaloric cooling applications. 展开更多
关键词 Shape memory alloy Phase transformation Elastocaloric cooling Temperature dependence Phase-field simulation
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Acupuncture with different frequencies for tobacco dependence:a randomized controlled trial
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作者 CHEN Shumin LIU Zhenyu +4 位作者 JI Jia CHANG Jin LI Zhihua WANG Yingying YANG Jinsheng 《Journal of Traditional Chinese Medicine》 2025年第3期651-659,共9页
OBJECTIVE:To observe the effect of different acupuncture frequencies on the abstinence rate which could be used as a reference for optimizing acupuncture cessation programs.METHODS:From July 2018 to June 2022,a total ... OBJECTIVE:To observe the effect of different acupuncture frequencies on the abstinence rate which could be used as a reference for optimizing acupuncture cessation programs.METHODS:From July 2018 to June 2022,a total of 220 smokers were recruited based on inclusion criteria and randomly divided into the high-frequency acupuncture group(HF group,n=110):5 times a week from the 1st to the 4th week,from weeks 5 to 8,three times a week and the low-frequency acupuncture group(LF group,n=110):3 times a week from the 1st to the 4th week,from weeks 5 to 8,twice a week,then treated for 8 weeks and followup at 1 month in Beijing.RESULTS:In total,162 subjects completed the whole study with a drop-out rate of 20.45%.The expiratory CO point abstinence rate was HF group 53/110(48.18%)vs LF group 41/110(37.27%)in Week 8(P=0.102)and HF group 46/110(41.82%)vs LF group 45/110(40.91%)in Week 12(P=0.891)and the HF acupuncture and LF acupuncture were nearly equal in the 8-week abstinence rate.In addition,both HF and LF acupuncture significantly reduced Fagerstr?m test for nicotine dependence scale(FTND)scores(P<0.05),Minnesota nicotine withdrawal scale(MNWS)scores(P<0.05),and Brief Questionnaire of Smoking Urges scale(QSU-Brief)scores(P<0.05),but HF acupuncture showed some superiority over LF acupuncture in relieving patients'smoking cravings(P<0.05).CONCLUSIONS:The study initially showed that both high-frequency acupuncture and low-frequency acupuncture treatment were safe and effective on smoking cessation for 8 weeks,but high-frequency acupuncture was advantageous in reducing smoking cravings.More accurate acupuncture frequency needs to be validated through larger clinical studies to optimize acupuncture smoking cessation programs. 展开更多
关键词 ACUPUNCTURE acupuncture frequency tobacco dependence smoking cessation
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Kinetic Analysis of pH Dependence in Electrocatalytic Reactions:Strategy and Pitfall
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作者 Yifei Xu Bingjun Xu 《Carbon and Hydrogen》 2025年第3期320-327,共8页
Electrocatalysis has been investigated as a promising strategy to utilize green electricity to produce renewable fuels,valuable chemicals,and treat pollutants.Electrode kinetic analysis is a potent technique in interr... Electrocatalysis has been investigated as a promising strategy to utilize green electricity to produce renewable fuels,valuable chemicals,and treat pollutants.Electrode kinetic analysis is a potent technique in interrogating reaction mechanisms and evaluating the electrocatalysts.Electron transfer(ET)and proton‐coupled electron transfer(PCET)processes are widely present in reaction networks of electrocatalysis.pH dependence of the kinetics is frequently employed to evaluate whether an elementary step involves proton participation,which is determined by both the reversibility and the specific reactants of electrode reactions.In this article,we discuss the pH dependence of two widely used formulations of the Butler–Volmer kinetics for a model PCET step and highlight a potential pitfall in kinetic analysis.This work aims to provide guiding principles for distinguishing ET and PCET steps via kinetic measurements in electrolytes in a broad range pH values. 展开更多
关键词 equilibrium potential kinetic analysis OVERPOTENTIAL pH dependence
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A bibliometric analysis of the relationship between the brain-derived neurotrophic factor and cognitive dysfunction due to alcohol dependence syndrome
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作者 Lin He Yan Deng +3 位作者 Xin Lyu Rongzhen Cui Jie Han Le Zhang 《Journal of Translational Neuroscience》 2025年第1期30-38,共9页
Objective:To evaluate the global liter-ature output on the relationship between brain-derived neurotrophic factor(BDNF)and cognitive function in al-cohol dependence syndrome using bibliometric methods and explore the ... Objective:To evaluate the global liter-ature output on the relationship between brain-derived neurotrophic factor(BDNF)and cognitive function in al-cohol dependence syndrome using bibliometric methods and explore the status and trends in this field.Method:The literature on the application of BDNF in cognitive impairment caused by alcohol dependence syndrome published from 1995 to 2023 were retrieved from Web of Science,and the relevant information(publication characteristics,country and institution,author,number of publications,citation,journal and research field,corresponding author,key words,etc.)was recorded.The bibliometrix R package was used for quantitative and qualitative analysis of publication output and author contributions.Result:A total of 99 articles were included.The overall number of publications in this field has increased over time.The countries and institutions that contributed the most to the field were the United States and the Academy of Medical Sciences of Iranian universities,respectively.Most of the authors were from the United States,followed by Spain,China,and Iran.Ceccanti M,Fiore M were the most productive authors.Publications with Ceccanti M had the highest h-index.The most cited reference author is Haenninen H(227 citations),and the number one published journal is Alcohol.Most articles were published in 2020(n=12)and 2022(n=11),followed by 2019 and 2021(n=10).The corresponding author has the largest number of publications from the United States,and more publications from a single country tend to have more cooperation from other countries.BDNF and alcohol appeared more frequently in various keyword clouds.However,significant differences remained in the author keyword cloud,keyword plus word cloud,and paper topic word cloud.Conclusion:BDNF has great potential in the application of cognitive dysfunction caused by alcohol dependence syndrome.Bibliometric methods and data visualization techniques can help understand the current state of research progress and enable relevant scholars and practitioners to predict the development trends in this field. 展开更多
关键词 alcohol dependence syndrome cognitive impairment brain-derived neurotrophic factor bibliometric analysis
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Thickness dependence of linearly polarized light-induced momentum anisotropy and inverse spin Hall effect in topological insulator Bi_(2)Te_(3)
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作者 Jiayi Qiu Jinling Yu +4 位作者 Zhu Diao Yunfeng Lai Shuying Cheng Yonghai Chen Ke He 《Chinese Physics B》 2025年第11期205-212,共8页
The thickness dependence of linearly polarized light-induced momentum anisotropy and the inverse spin Hall effect(PISHE)in topological insulator(TI)Bi_(2)Te_(3)films has been investigated.A significant enhancement of ... The thickness dependence of linearly polarized light-induced momentum anisotropy and the inverse spin Hall effect(PISHE)in topological insulator(TI)Bi_(2)Te_(3)films has been investigated.A significant enhancement of the PISHE signal is observed in the 12-quintuple-layer(QL)Bi_(2)Te_(3)film compared with that of the 3-and 5-QL samples,whereas a minimal value of photoinduced momentum anisotropy is found in the 12-QL sample.The photoinduced momentum anisotropy and the PISHE in Bi_(2)Te_(3)films are more than three and two orders of magnitude larger than those in Bi2Se3 films grown on SrTiO_(3)substrates,respectively.The 3-QL sample exhibits a sinusoidal dependence of the PISHE current on the light spot position,while the 5-QL and 12-QL samples show aW-shaped dependence,which arises from the different angles between the coordinate axis x and the in-plane crystallographic axis of the Bi_(2)Te_(3)films.Our findings demonstrate the critical role of film thickness in modulating both the photoinduced momentum anisotropy and the PISHE current,thereby suggesting a thickness-engineering strategy for designing novel optoelectronic devices based on TIs. 展开更多
关键词 photoinduced inverse spin Hall effect photoinduced momentum anisotropy three-dimensional topological insulator Bi_(2)Te_(3) thickness dependence
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From fledging to independence:Post-fledging movements and space use of the Crested Ibis(Nipponia nippon)
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作者 Yu Lei Xianglong Xu +6 位作者 Yuanxing Ye Chao Wang Baoping Qing Wenbin Duan Jiaqi Yan Yongjie Huang Changqing Ding 《Avian Research》 2025年第3期362-371,共10页
The post-fledging period, extending from fledging to independence, is a crucial life stage characterized by high mortality due to fledglings' limited mobility and inexperience. During this stage, fledglings gradua... The post-fledging period, extending from fledging to independence, is a crucial life stage characterized by high mortality due to fledglings' limited mobility and inexperience. During this stage, fledglings gradually increase their mobility, leave their parents, disperse from their natal site, and respond to the challenges of new environments. Characterizing these post-fledging movements and space use is essential for understanding juvenile survival strategies and devising targeted conservation measures. The Crested Ibis (Nipponia nippon), an endangered species and a highly protected animals at the national level in China, has seen limited research on its post-fledging movements and space use. From 2015 to 2023, we utilized biologgers, combined with field surveys, to study the movement and space use characteristics of 37 fledglings in Hanzhong City, Shaanxi Province, China, over a two-month post-fledging period. We quantified changes in activity levels (based on overall dynamic body acceleration), independence timing, onset of post-fledging dispersal, habitat selection, and daily activity rhythms after independence. Our results revealed individuals began independent living 26.23 ± 2.34 days post-fledging and onset of dispersal at 25.58 ± 2.33 days, with a range area at the natal of 2.08 ± 0.56 km^(2). The initial 30 days post-fledging are characterized as an ontogenetic phase marked by a rapid increase in body activity level. Fledglings preferred paddy fields during the independent period rather than the forests they relied on before independence. Interestingly, the daily activity rhythm, particularly foraging behavior, peaked at noon—contrasting with the expected morning and evening activity peaks—likely as an adaptation to avoid periods of peak human activity. Additionally, drowning, collisions, and predation in paddy fields are noteworthy causes of fledgling mortality. Consequently, we recommend protecting a 2-km^(2) area around the nest site for at least two-month post-fledging, implementing safety measures around power lines and cesspools. Additionally, reducing human disturbances near foraging habitats and expanding space within paddy fields would help mitigate survival pressures on fledglings. 展开更多
关键词 Behavioral development hypothesis Daily activity rhythms Dependent period Habitat selection Physical mobility development Post-fledging dispersal
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主梁断面三自由度耦合非线性颤振分析 被引量:1
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作者 胡朋 袁邦荣 +2 位作者 韩艳 李凯 陈旭 《工程力学》 北大核心 2026年第1期174-184,共11页
为分析主梁断面三自由度耦合非线性颤振特性并考察侧向自由度对非线性颤振特性的影响,以某典型箱梁断面为例,建立了一种考虑18个幅变颤振导数的三自由度耦合非线性颤振分析方法。采用强迫振动数值模拟技术识别了该断面不同折减风速和不... 为分析主梁断面三自由度耦合非线性颤振特性并考察侧向自由度对非线性颤振特性的影响,以某典型箱梁断面为例,建立了一种考虑18个幅变颤振导数的三自由度耦合非线性颤振分析方法。采用强迫振动数值模拟技术识别了该断面不同折减风速和不同振幅下的18个幅变颤振导数。基于识别的幅变颤振导数采用建立的三自由度耦合非线性颤振分析方法计算了该断面的非线性颤振响应,并与自由振动数值模拟结果进行对比,验证了幅变颤振导数识别结果和非线性颤振分析方法的准确性。量化了侧向自由度对非线性颤振的影响,并揭示了其影响机制。研究结果表明,侧向自由度的参与不仅在一定程度上降低颤振临界风速,也会增大非线性颤振的稳态振幅,且振幅越大这种增幅越明显,这主要是因为侧向自由度的引入降低了扭转模态分支的阻尼比,进而降低了系统的稳定性。进一步地,组成扭转模态分支阻尼比的各项中,扭转-竖向耦合气动阻尼比与扭转-侧向耦合气动阻尼比项均不利于扭转模态运动的稳定。 展开更多
关键词 非线性颤振 箱梁 侧向振动 幅变颤振导数 数值模拟
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非成员依赖如何影响农民合作社公司化
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作者 张舰 王永胜 《中国农村经济》 北大核心 2026年第1期137-160,共24页
农业合作化是实现农业强国的重要实践方向和推动力量。然而,中国农民合作社公司化现象普遍,公司化使合作社这种有别于公司的组织形态难以发挥作用。本文旨在从合作社依赖对象(成员与非成员)视角理解合作社公司化的内在机理。本文构建了... 农业合作化是实现农业强国的重要实践方向和推动力量。然而,中国农民合作社公司化现象普遍,公司化使合作社这种有别于公司的组织形态难以发挥作用。本文旨在从合作社依赖对象(成员与非成员)视角理解合作社公司化的内在机理。本文构建了一个包含异质性成员、非成员依赖与合作社公司化的分析框架,分析发现:当合作社对非成员的依赖程度很高时,即当合作社转入的土地和收购非成员农产品很多(从而越不依赖于成员)时,合作社理事会就会有动机和激励扩大其持股比例与合作社盈余按股分红比例,合作社公司化程度也会提高。数值模拟分析和利用调研数据进行的计量分析均证实了非成员依赖与合作社公司化之间的这种因果关系。本文的研究结论不仅能为理解中国合作社公司化现象提供新视角,也能为农业经营主体变革背景下合作社如何进一步处理好效率与公平问题提供政策参考。 展开更多
关键词 农民合作社 非成员依赖 合作社公司化 盈余分配
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边缘计算中依赖任务的联合调度与缓存优化策略
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作者 张文柱 唐文迪 +1 位作者 刘润滋 边跃伟 《计算机工程与应用》 北大核心 2026年第4期96-110,共15页
为了解决依赖任务结构带来的调度复杂性及缓存资源利用不足的问题,提出了一种联合调度与缓存的优化策略。构建边、端计算模型,并以最小化系统总时延、能耗和负载方差增量为优化目标;设计一种支持动态依赖的层级化虚拟任务调度与优化算法... 为了解决依赖任务结构带来的调度复杂性及缓存资源利用不足的问题,提出了一种联合调度与缓存的优化策略。构建边、端计算模型,并以最小化系统总时延、能耗和负载方差增量为优化目标;设计一种支持动态依赖的层级化虚拟任务调度与优化算法,有效减少跨节点通信和资源消耗,同时确定全局最优调度序列;将该优化问题分解为资源分配和卸载及缓存决策两个子问题,利用凸优化理论求解资源分配,并引入基于任务类型价值的服务缓存策略,以提升缓存效率;设计一种任务卸载与服务缓存协同优化算法,通过迭代获得任务的最优卸载决策和缓存策略。仿真结果表明,该协同优化算法能够充分利用缓存资源,在确保依赖任务顺序的同时,有效降低系统时延与能耗,并提升系统的负载均衡性。 展开更多
关键词 边缘计算 依赖任务 任务调度 服务缓存
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乙酸钠与抗生素对大肠杆菌时间依赖的hormesis及联合作用判别
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作者 沈洪艳 姚泽宇 +1 位作者 王嘉飞 孙昊宇 《环境科学学报》 北大核心 2026年第1期446-454,共9页
抗生素生产过程中产生的废水是环境中抗生素的重要工业来源,其对细菌的“低促高抑”hormesis效应显著影响着抗生素类污染物的生态风险评估.同时,乙酸钠作为抗生素生产中的补充碳源和缓冲剂,未被完全利用的部分随废水排出后与抗生素在环... 抗生素生产过程中产生的废水是环境中抗生素的重要工业来源,其对细菌的“低促高抑”hormesis效应显著影响着抗生素类污染物的生态风险评估.同时,乙酸钠作为抗生素生产中的补充碳源和缓冲剂,未被完全利用的部分随废水排出后与抗生素在环境中共存.目前抗生素的风险评估尚未考虑乙酸钠的影响.鉴于此,本文选取大肠杆菌(Escherichia coli,E.coli)为受试生物,选取头孢噻肟钠(Cefotaxime sodium,CTX)和环丙沙星(Ciprofloxacin,CIP)两种生产量大且制药废水常检出的抗生素为受试物,探究不同乙酸钠浓度下,这两种抗生素对不同生长周期细菌的毒性效应,并分析乙酸钠与单一及二元抗生素对E.coli毒性的交互作用.结果表明,CTX和CIP及其二元混合物对E.coli均表现出浓度和时间依赖的hormesis效应.在相同时下,与对照组相比,实验组的最大促进率和EC_(50)随乙酸钠浓度的增加而逐渐减小,表明毒性作用逐渐增强.利用独立作用模型(Independent Action,IA),发现CTX和CIP联合作用模式同样随暴露时间和乙酸钠浓度发生变化,并且乙酸钠与抗生素对抑制E.coli生长的交互效应呈协同作用.随乙酸钠浓度的增加,协同作用逐渐增强.由此可见,乙酸钠可显著增强抗生素对细菌的毒性效应,削弱低浓度抗生素对细菌生长的促进作用.此外,抗生素暴露时间越长,毒性作用越强.本研究为理解乙酸钠与抗生素的相互作用及其潜在危害、控制和评价制药废水中混合污染物共存的生态风险提供了理论依据. 展开更多
关键词 乙酸钠 抗生素 hormesis效应 交互效应 时间依赖性
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基于均一化气温数据集的中国海拔依赖型增暖研究
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作者 胡宜昌 《气候变化研究进展》 北大核心 2026年第1期28-40,共13页
中国气温存在海拔依赖型增暖(EDW),但增暖趋势随海拔升高而增强(正EDW)或是减弱(负EDW),不同研究给出的结论并不完全一致。文中利用中国目前空间覆盖度较高的气象站逐日均一化气温数据集,研究1961—2021年及该期间多个子时期的气温变化... 中国气温存在海拔依赖型增暖(EDW),但增暖趋势随海拔升高而增强(正EDW)或是减弱(负EDW),不同研究给出的结论并不完全一致。文中利用中国目前空间覆盖度较高的气象站逐日均一化气温数据集,研究1961—2021年及该期间多个子时期的气温变化趋势与海拔高度的关系。结果表明,最低气温(Tmin)、最高气温(Tmax)、平均气温(Tmean)的年平均值均显示存在正EDW,青藏高原及其周边区域更显著;季节平均值的EDW差异明显,Tmax、Tmean以及1981年以来的Tmin春季存在显著的负EDW,其他季节平均Tmin、Tmax、Tmean绝大多数情况为显著的正EDW;月平均值的EDW表现出明显的月份差异,与Tmin、Tmean相比,Tmax对应的月份差异在各个时期都最显著,11月或12月正EDW达到最强,随后减弱,3月或4月负EDW达到最强,至6月转变为正EDW,6—10月正EDW强度相对稳定。考虑到纬度差异可能对EDW信号检测造成的影响,针对不同纬度带单独研究分析,所得结果与上述结论一致。中国气温的EDW特征与全球变暖背景下高海拔地区下垫面变化密切相关,EDW及其季节差异很可能是由积雪、植被覆盖变化等对应的辐射收支强迫造成的。 展开更多
关键词 气温 增温趋势 海拔依赖型增暖(EDW) 均一化数据集
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交叉电项针治疗卒中相关性肺炎呼吸机依赖患者的临床疗效
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作者 蔡国锋 孙波 +8 位作者 庄哲 贾坤平 王虹 郭祀慧 崔成 高子茵 吴珍琦 马兴武 孙满超 《中国急救医学》 2026年第1期50-55,共6页
目的观察交叉电项针对卒中相关性肺炎呼吸机依赖患者脱机的影响。方法将90例卒中相关性肺炎呼吸机依赖患者采用随机数字表法分为项针组、电项针组和交叉电项针组,每组30例。三组在相同的基础针灸、对症治疗及基础护理的基础上,分别采用... 目的观察交叉电项针对卒中相关性肺炎呼吸机依赖患者脱机的影响。方法将90例卒中相关性肺炎呼吸机依赖患者采用随机数字表法分为项针组、电项针组和交叉电项针组,每组30例。三组在相同的基础针灸、对症治疗及基础护理的基础上,分别采用项针、电项针和交叉电项针三种不同的针刺治疗方案,共治疗28 d。对三组膈肌呼吸变异度(TFdi)、动脉氧分压(PaO_(2))、动脉二氧化碳分压(PaCO_(2))、肺炎严重指数(PSI)、格拉斯哥昏迷评分(GCS评分)和脱机成功率进行比较,探讨三组治疗方案对卒中相关性肺炎呼吸机依赖患者的治疗效果。结果三组组内治疗前后比较,TFdi、PaO_(2)、PaCO_(2)、PSI、GCS等相关指标均有改善(P<0.05);治疗后三组TFdi、PaO_(2)、PaCO_(2)、PSI、GCS等指标改善程度,交叉电项针组>电项针组>项针组(P<0.05)。交叉电项针组脱机成功率86.67%,电项针组脱机成功率66.67%,项针组脱机成功率50.00%,结合各组治疗后各项指标及最终脱机成功率,交叉电项针组治疗效果优于电项针组和项针组(P<0.05)。结论交叉电项针治疗能改善卒中相关性肺炎呼吸机依赖患者的TFdi、PaO_(2)、PaCO_(2)、PSI、GCS等相关指标,提高脱机成功率。 展开更多
关键词 交叉电项针 卒中相关性肺炎 呼吸机依赖
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Molecular dynamics study on temperature and strain rate dependences of mechanical tensile properties of ultrathin nickel nanowires 被引量:3
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作者 王卫东 易成龙 樊康旗 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3353-3361,共9页
Based on the EAM potential, a molecular dynamics study on the tensile properties of ultrathin nickel nanowires in the (100〉 orientation with diameters of 3.94, 4.95 and 5.99 nm was presented at different temperature... Based on the EAM potential, a molecular dynamics study on the tensile properties of ultrathin nickel nanowires in the (100〉 orientation with diameters of 3.94, 4.95 and 5.99 nm was presented at different temperatures and strain rates. The temperature and strain rate dependences of tensile properties were investigated. The simulation results show that the elastic modulus and the yield strength are gradually decreasing with the increase of temperature, while with the increase of the strain rate, the stress--strain curves fluctuate more intensely and the ultrathin nickel nanowires rupture at one smaller and smaller strain. At an ideal temperature of 0.01 K, the yield strength of the nanowires drops rapidly with the increase of strain rate, and at other temperatures the strain rate has a little influence on the elastic modulus and the yield strength. Finally, the effects of size on the tensile properties of ultrathin nickel nanowires were briefly discussed. 展开更多
关键词 ultrathin nickel nanowires temperature dependence strain rate dependence tensile properties molecular dynamics simulation
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汉语“主动宾句”的切分问题
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作者 周韧 《中国语文》 北大核心 2026年第1期17-36,139,共21页
本文讨论现代汉语“主动宾句”(即SVO句)的切分问题。文章首先通过句子片段测试和意义原则等判断标准,对S︳VO切分和SV︳O切分进行了成分测试。根据测试结果,本文认为,S︳VO切分和SV︳O切分不是100分与0分的对错判断,而是98分和80分的... 本文讨论现代汉语“主动宾句”(即SVO句)的切分问题。文章首先通过句子片段测试和意义原则等判断标准,对S︳VO切分和SV︳O切分进行了成分测试。根据测试结果,本文认为,S︳VO切分和SV︳O切分不是100分与0分的对错判断,而是98分和80分的倾向关系。按照这个结论,SVO句应以三分的扁平结构作为起点,再考虑实际的语用因素和韵律因素,最终既可以实现为S︳VO切分,也可以实现为SV︳O切分。文章进而讨论了与结构切分相关的三个重要议题,分别是:与成分统制相关的约束关系判定,与论元结构相关的主动宾题元角色倚变现象,与结构依赖原则相关的语法结构设计方案。我们认为,在基于扁平式SVO结构的体系下,上述议题都可以得到妥善处理,并不会造成语法分析系统的混乱。 展开更多
关键词 SVO句 成分测试 成分统制 结构依赖 扁平结构
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