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Relationship between Parent-Child Attachment and Problem Behaviors among Chinese Firstborn Children in Family Transitions: A Meta-Analysis
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作者 Cong Liu Mohd Nazri Abdul Rahman Nur Eva 《International Journal of Mental Health Promotion》 2023年第11期1161-1172,共12页
The implementation of China’s three-child fertility policy has led to a notable increase in multiple-child families.Notably,firstborn children experience a significant transition from being an only child to a non-only ... The implementation of China’s three-child fertility policy has led to a notable increase in multiple-child families.Notably,firstborn children experience a significant transition from being an only child to a non-only child.This transition is associated with problematic behaviors,affecting their social adjustment,sibling relationships,and family harmony.Although several studies have examined the relationship between parent-child attachment and problem behaviors exhibited byfirstborn children during family transitions,thefindings have been inconsistent.Hence,a meta-analytic study was undertaken to elucidate the inconsistencies in this relationship and explore the moderating factors that may contribute to these discrepancies.Using a systematic literature retrieval and screening method,12 effect sizes were derived from the 10 eligible articles,encompassing a sample size of 5319.The meta-analysis demonstrated a low negative association between parent-child secure attachment and problem behaviors exhibited byfirstborn children during family transitions.Furthermore,the present study investigates potential moderator factors,such as children’s age and geographic region,to gain a more nuanced understanding of the relationship.Consequently,the establishment of parent-child attachment relationships has the potential to mitigate problem behaviors observed infirst-born children during family transitions.The implications of thesefindings indicate that parents can nurture secure attachment bonds with their children by demonstrating sensitive responsiveness,employing positive parenting practices,and fostering emotional availability.These efforts contribute to the cultivation of secure internal working models and positive behavioral manifestations withinfirst-born children,which in turn affect their relationships with siblings. 展开更多
关键词 parent-child attachment problem behaviors firstborn children META-ANALYSIS moderation effect
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Parenting Style and Shyness of Late Adolescence Students in China: The Mediating Effect of Parent-Child Attachment
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作者 Chen YingMin Liu XiaoRan Yu LiNa Wu YunPeng Han Xue 《Psychology Research》 2015年第7期404-412,共9页
关键词 青年学生 父母 教养 亲子 中介效应 青少年学生 中国 中介作用
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Morphology prediction of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) crystal in different solvent systems using modified attachment energy model
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作者 Fang Chen Tao Zhou +4 位作者 Lijie Li Chongwei An Jun Li Duanlin Cao Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期181-193,共13页
In order to theoretically study the growth morphology of dihydroxylammonium 5,5’-bistetrazole-1,1’-dio late(TKX-50)crystal in different solvent systems,crystal–solvent models were established,and then molecular dyn... In order to theoretically study the growth morphology of dihydroxylammonium 5,5’-bistetrazole-1,1’-dio late(TKX-50)crystal in different solvent systems,crystal–solvent models were established,and then molecular dynamics(MD)methods were adopted as a means to simulate particle motion.Modified attachment energy(MAE)model was employed to calculate the growth morphology of TKX-50.The simulation results demonstrate that COMPASS force field and RESP charge are suitable for molecular dynamics simulation of TKX-50.The morphologically dominant growth surfaces of TKX-50 in vacuum are(020),(011),(11–1),(100)and(120),respectively.In water(H_(2)O)and N,N-dimethylformamide(DMF)solvents,the(11–1)face is the largest in the habit face,the growth rate of(020)face becomes faster.With the increase of temperature,the aspect ratios of TKX-50 crystal in DMF solvent increase,and the areas of the(120)faces decrease.In ethylene glycol/H_(2)O mixed solvent system with volume ratio of 1/1,aspect ratio of TKX-50 is relatively small.In formic acid/H_(2)O mixed solvents with different volume ratios(1/4,1/3,1/2,1/1 and 2/1),aspect ratio of TKX-50 is relatively small when volume ratio is 1/2. 展开更多
关键词 TKX-50 Crystal morphology Solvents Modified attachment energy model Molecular dynamics simulation
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Cytokine changes and embryo attachment in mouse endometrial cells following treated with peripheral blood mononuclear cells(PBMCs)expressing ectopic hCG,and hCG-activated PBMCs
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作者 Delsuz Rezaee Mojgan Bandehpour +3 位作者 Bahram Kazemi Saiyad Bastaminejad Sajad Najafi Mohammad Salehi 《Asian pacific Journal of Reproduction》 2023年第2期90-96,共7页
Objective:To compare the effect of human chorionic gonadotropin(hCG)-producing peripheral blood mononuclear cells(PBMCs)and PBMCs activated by hCG in vitro and expressions of related immune genes in mouse implantation... Objective:To compare the effect of human chorionic gonadotropin(hCG)-producing peripheral blood mononuclear cells(PBMCs)and PBMCs activated by hCG in vitro and expressions of related immune genes in mouse implantation.Methods:hCG-producing PBMCs(transfected PBMC)and PBMCs activated by hCG in vitro were introduced into isolated mouse endometrial cells,while cell cultures were divided into four groups:the control,PBMC,transfected,and activated PBMC groups.The expression of studied genes(IL-1β,IL-6,Lif,and Vegf)was evaluated and blastocyst attachment on the cocultured cells(isolated endometrial cells and PBMC cells)was monitored in all four groups.Results:Data showed that expression decreased in the PBMC group compared to the treated PBMC(transfected and activated PBMCs)and increased in transfected PBMC compared to the activated PBMC.Attachment and migration of blastocysts were dramatically enhanced in the transfected PBMC group compared to the activated PBMC group(P<0.05).Conclusions:Use of hCG-producing PBMCs(transfected PBMC)has more influence on endometrial receptivity. 展开更多
关键词 Peripheral blood mononuclear cells HCG Embryo attachment Immune response Immune cells In vitro Expression gene
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Landscape Upgrading and Transformation of Old Urban Parks from the Perspective of Place Attachment:A Case Study of Nanchang Bayi Park
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作者 Baoyong LI Yuanqing WEN +1 位作者 Bo PENG Huimin TAN 《Meteorological and Environmental Research》 CAS 2023年第2期28-34,41,共8页
On the basis of combing the relevant theories of place attachment, the planning framework of upgrading and reconstruction of old parks based on place attachment was put forward. Taking Nanchang Bayi Park as an example... On the basis of combing the relevant theories of place attachment, the planning framework of upgrading and reconstruction of old parks based on place attachment was put forward. Taking Nanchang Bayi Park as an example, the methods and key points of landscape improvement and transformation of old urban parks based on place attachment were explained to provide new ways and references for the renewal of old urban parks. 展开更多
关键词 Landscape upgrading and transformation Old urban parks Place attachment
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The Evolving Bipartite Network and Semi-Bipartite Network Models with Adjustable Scale and Hybrid Attachment Mechanisms
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作者 Peng Zuo Zhen Jia 《Open Journal of Applied Sciences》 2023年第10期1689-1703,共15页
The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex... The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex networks. Previous bipartite models were proposed to mostly explain the principle of attachments, and ignored the diverse growth speed of nodes of sets in different bipartite networks. In this paper, we propose an evolving bipartite network model with adjustable node scale and hybrid attachment mechanisms, which uses different probability parameters to control the scale of two disjoint sets of nodes and the preference strength of hybrid attachment respectively. The results show that the degree distribution of single set in the proposed model follows a shifted power-law distribution when parameter r and s are not equal to 0, or exponential distribution when r or s is equal to 0. Furthermore, we extend the previous model to a semi-bipartite network model, which embeds more user association information into the internal network, so that the model is capable of carrying and revealing more deep information of each user in the network. The simulation results of two models are in good agreement with the empirical data, which verifies that the models have a good performance on real networks from the perspective of degree distribution. We believe these two models are valuable for an explanation of the origin and growth of bipartite systems that truly exist. 展开更多
关键词 Bipartite Networks Evolving Model Semi-Bipartite Networks Hybrid attachment Degree Distribution
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Anchor Attachment蛋白在结直肠癌中表达增强 被引量:1
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作者 左富义 李世拥 +2 位作者 于波 安萍 杨梅 《基础医学与临床》 CSCD 北大核心 2008年第12期1248-1250,共3页
目的探讨Anchor Attachment蛋白(AAP)的表达与结直肠癌浸润、转移的关系及临床意义。方法免疫组织化学法检测AAP的表达,分析AAP表达水平与肿瘤临床病理特征之间的关系;并用酶联免疫吸附(ELISA)法检测血清中AAP表达水平。结果结直肠正常... 目的探讨Anchor Attachment蛋白(AAP)的表达与结直肠癌浸润、转移的关系及临床意义。方法免疫组织化学法检测AAP的表达,分析AAP表达水平与肿瘤临床病理特征之间的关系;并用酶联免疫吸附(ELISA)法检测血清中AAP表达水平。结果结直肠正常肠黏膜、癌原发灶、淋巴结和肝转移灶中AAP的表达阳性率分别为20.5%、53.0%、69.8%和80.0%;癌原发灶、转移淋巴结和肝转移灶中AAP表达阳性率均显著高于正常肠黏膜组织(P<0.01),转移淋巴结和肝转移灶中AAP阳性率高于癌原发灶(P<0.05);淋巴结转移患者和肝转移患者的原发灶AAP阳性率显著高于无转移者(P<0.01);Dukes分期A、B、C、D期患者AAP阳性率逐渐增高,各分期之间差异显著(P<0.01)。83例结直肠癌患者血清AAP水平为(6.3±2.8)μg/L,显著高于30例健康志愿者的(2.2±0.9)μg/L,(t=6.976,P<0.01);Dukes分期A、B期患者血清AAP水平为(5.2±2.6)μg/L,显著低于C、D期患者的(7.1±2.9)μg/L(P<0.05)。结论检测外周静脉血AAP水平对预测和判断结直肠癌病情和肝转移有重要意义。 展开更多
关键词 结直肠肿瘤 ANCHOR attachment蛋白 肿瘤浸润 转移
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场所依赖(place attachment):一种游憩行为现象的研究框架 被引量:201
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作者 黄向 保继刚 Wall Geoffrey 《旅游学刊》 CSSCI 北大核心 2006年第9期19-24,共6页
“场所依赖”理论是解释“某些地方与人之间似乎存在着一种特殊的依赖关系”这个客观现象的有效理论工具,并已成为西方休闲和游憩研究的一个热点,而在我国仍然处于空白状态。本文讨论了场所和场所依赖的概念及其发展,介绍了西方场所依... “场所依赖”理论是解释“某些地方与人之间似乎存在着一种特殊的依赖关系”这个客观现象的有效理论工具,并已成为西方休闲和游憩研究的一个热点,而在我国仍然处于空白状态。本文讨论了场所和场所依赖的概念及其发展,介绍了西方场所依赖研究的最新进展。文章的主要贡献包括:(1)首次将以游憩为角度开展研究的场所依赖理论引进我国;(2)用数学方法示意理解场所依赖的结构;(3)构建了场所依赖理论的CDEEM研究框架。文章还探讨了场所依赖理论的应用前景。 展开更多
关键词 场所依赖 游憩行为 理论框架
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Improving bubble-particle attachment during the flotation of low rank coal by surface modification 被引量:27
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作者 Haishan Hu Ming Li +1 位作者 Lulu Li Xiuxiang Tao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第2期217-223,共7页
Based on the problems caused by many oxygen-containing functional groups and poor floatability on the surface of low rank coal,the characteristics of low rank coal were analyzed systematically by means of scanning ele... Based on the problems caused by many oxygen-containing functional groups and poor floatability on the surface of low rank coal,the characteristics of low rank coal were analyzed systematically by means of scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-Ray photoelectron spectroscopy(XPS)techniques.The bubble-particle induction time was used to determine the characterization of the bubble-particle attachment,and the bubble-particle attachment of low rank coal modified by soaking the coal samples in an acid or alkaline solution was analyzed.The floatability of the modified coal surface was verified by flotation tests.The results show that the particle size of 0.125–0.074 mm of the coal sample exhibited better bubble-particle attachment characteristics.The small bubble,the larger approach velocity of bubble and the larger bubble deformation were more helpful to enhance the bubbleparticle attachment.For an acid solution,the smaller the p H was and the longer the soaking time was,the better the floatability of the coal sample and the higher the combustible material recovery were.The combustible material recovery of low rank coal was increased to 78.79%by soaking the sample in an acid solution of pH=0 for 180 min.On the contrary there was a best concentration for the alkaline solution. 展开更多
关键词 Low RANK coal Induction time Modification FLOTATION Bubble-particle attachment
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Attachment Styles are Related to ERPs Elicited to Angry Faces in an Oddball Paradigm 被引量:5
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作者 Ruth E. Mark Fienke I. M. Geurdes Marrie H. J. Bekker 《Journal of Behavioral and Brain Science》 2012年第1期128-140,共13页
Attachment theory suggests that anxious attachment is associated with hypervigilance to threatening social stimuli, and avoidant attachment with avoidance or suppression of processing such stimuli. Twenty-five student... Attachment theory suggests that anxious attachment is associated with hypervigilance to threatening social stimuli, and avoidant attachment with avoidance or suppression of processing such stimuli. Twenty-five students viewed angry, fearful and neutral female faces in four visual oddball tasks, and completed the Attachment Style Questionnaire, the Autonomy-Connectedness Scale, and Anxiety and Depression subscales of the Symptom Checklist-90. When the oddballs were angry faces in a background of neutral frequents, we found higher levels of autonomy and secure attachment to be related to larger N100 and smaller P300 amplitudes;higher levels of anxious attachment were, on the contrary, associated with smaller N100 and larger P300 amplitudes. Variation in attachment is related to approaching, or withdrawing from threatening stimuli, and ERP-techniques add to our understanding of how the attachment system actually works. 展开更多
关键词 EVENT-RELATED POTENTIALS attachment STYLES or Dimensions AUTONOMY Anxiety Attentional Bias Theory
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Contribution of attachment insecurity to health-related quality of life in depressed patients 被引量:1
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作者 Alexander M Ponizovsky Angela Drannikov 《World Journal of Psychiatry》 SCIE 2013年第2期41-49,共9页
AIM: To examine the individual contributions of insecure attachment styles and depression symptom severity to health-related quality of life(HRQo L) in patients diagnosed with adjustment disorder(AJD) with depressed m... AIM: To examine the individual contributions of insecure attachment styles and depression symptom severity to health-related quality of life(HRQo L) in patients diagnosed with adjustment disorder(AJD) with depressed mood. METHODS: Participants were 67 patients diagnosed with International Classification of Diseases, Tenth edition AJD with depressed mood, who completed standardised self-report questionnaires measuring study variables. Mean scores and SDs were computed for the outcome and predictor measures. Pearson correlations among the measures were computed. The study hypotheses were tested using analysis of variance(ANOVA) and multiple regression analyses. All analyses were performed using the SPSS-17 software package(SPSS Inc., Chicago, IL, United States).RESULTS: ANOVA showed a significant main effect of the insecure attachment styles on depression symptom severity and life satisfaction scores. The results suggestthat depressive symptoms were more severe(F = 4.13, df = 2.67, P < 0.05) and life satisfaction was poorer(F = 5.69, df = 2.67, P < 0.01) in both anxious-ambivalently and avoidantly attached patients compared with their securely attached counterparts, whereas the two insecure groups did not significantly differ by these variables. The anxious/ambivalent attachment style and depression symptom severity significantly contributed to HRQo L, accounting for 21.4% and 29.7% of the total variance, respectively [R2 = 0.79; Adjusted R2 = 0.77; F(5, 67) = 33.68, P < 0.0001], even after controlling for gender, marital and employment status confounders.CONCLUSION: The results show that the anxious/ambivalent attachment style together with depression symptom severity substantially and independently predict the HRQo L outcome in AJD with depressed mood. 展开更多
关键词 attachment INSECURITY ADULT attachment style HEALTH-RELATED quality of life Depression Adjustment DISORDER
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Nonculturability of the pathogenic Vibrio parahaemolyticus in live culture of Grateloupia turuturu is associated with bacterial attachment to the algal thalli 被引量:1
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作者 LIU Feng PANG Shaojun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第6期92-103,共12页
The invasive red alga Grateloupia turuturu Yamada could turn Vibrio parahaemolyticus into nonculturable state in live algal culture.In order to elucidate the mechanism of such an effect,a series of culture experiments... The invasive red alga Grateloupia turuturu Yamada could turn Vibrio parahaemolyticus into nonculturable state in live algal culture.In order to elucidate the mechanism of such an effect,a series of culture experiments were performed in this investigation based on three hypothesized causes,namely bacterial attachment,production of reactive oxygen species (ROS) and the discharge of water soluble secondary metabolic compounds.The results reveal that attachment to the thallus surface of G.turuturu was the major reason for the decrease of V.parahaemolyticus in seawater.Further investigations show that V.parahaemolyticus attachment to the surface of algal thallus in live cultures of seaweeds was a common phenomenon.However,the disappearance of the culturability of V.parahaemolyticus occurred only on the thallus of G.turuturu over 72 h among all six algal species tested.Electron microscopic scanning shows that most of V.parahaemolyticus attached to G.turuturu changed from the initial normal bacilli to coccoid-shape after 72 h.The enclosure experiments by enclosing the algal thallus in tubes demonstrate that the nonculturability of V.parahaemolyticus in the water of live culture of G.turuturu occurred after the physical contact of the V.parahaemolyticus to the alga.The capacity of G.turuturu in affecting the culturability of V.parahaemolyticus was not influenced after inhibition of photosynthesis by treatment of 3(3,4dichlorophenyl)-1 ,1dimethyl urea (DCMU) at non-lethal levels.Production of reactive oxygen species after addition of live culture of bacteria was excluded by on-line analyzing the oxidation of dichlorohydrofluorescein (DCFH) to dichlorofluorescein (DCF) in the presence of peroxidase on a VersaFluor fluorometer. 展开更多
关键词 Grateloupia turuturu attachment Vibrio parahaemolyticus nonculturability effective quantum yield
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Zoospores of Undaria pinnatifida:their efficiency to attach under different water velocities and conjugation behavior during attachment 被引量:1
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作者 PANG Shaojun SHAN Tifeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第6期94-101,共8页
In the invading course of Undaria pinnatifida, zoospore attachment in a dynamically changed subtidal water environment is crucial for the establishment of a potential population in alien waters. Among many abiotic fac... In the invading course of Undaria pinnatifida, zoospore attachment in a dynamically changed subtidal water environment is crucial for the establishment of a potential population in alien waters. Among many abiotic factors that may interfere with the attachment process, water velocity is the most important one. In this investigation, the effect of water velocity on zoospore attachment of U. pinnatifida was investigated in an artificially designed system. It was found that freshly released zoospores that were transported by water flowing at 0 -16 cm/s showed no difficulty in attaching the smooth surface. Zoospore attachment decreased at elevated water flowing rates. At 70 cm/s no spore attachment occurred. Spores that have settled on glass slide for up to 1 h could not be stripped away by flowing water at a rate of 129 cm/s, the same was true of the 20 d old filamentous gametophytes. It was found that more than 70% of free-swimming zoospores tended to settle down adjacent to the settled spores and formed conjugated clusters from two up to a few hundred cells in still culture. 展开更多
关键词 Undaria pinnatifida zoospore attachment water velocity FERTILIZATION
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The Role of Internet Pornography Use and Cyber Infidelity in the Associations between Personality, Attachment, and Couple and Sexual Satisfaction 被引量:2
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作者 Anik Ferron Yvan Lussier +1 位作者 Stéphane Sabourin Audrey Brassard 《Social Networking》 2017年第1期1-18,共18页
Although adults in romantic relationships currently show more openness to online sexual behaviors [1], these behaviors can nevertheless increase couple conflicts and instability [2]. In the current study, we assess th... Although adults in romantic relationships currently show more openness to online sexual behaviors [1], these behaviors can nevertheless increase couple conflicts and instability [2]. In the current study, we assess the mediating role of Internet pornography use and cyber infidelity in the relationship between 1) personality and attachment, and 2) couple and sexual satisfaction. A total of 779 participants in couple relationships (average age = 29.9 years) completed a series of online questionnaires. According to their responses, 65% of participants visited an adult site at least once during the six months preceding the study, while 16.3% did so multiple times per week. Path model results showed that Internet pornography use and cyber infidelity were sequential mediators between, on the one hand, personality and attachment, and on the other hand, couple and sexual satisfaction. The discussion highlights the importance of properly documenting the correlates of online sexual behavior to better understand new couple realities and dynamics. 展开更多
关键词 Internet Pornography CYBER INFIDELITY COUPLE SATISFACTION Sexual SATISFACTION PERSONALITY attachment
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Alleviation for contact stresses in curvic attachments 被引量:1
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作者 蒋翔俊 张优云 +1 位作者 王鑫 袁淑霞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第5期65-70,共6页
This paper studied the contact stresses in curvic attachments.The principal purpose of this research is to employ a method of alleviating the fluctuating hoop stresses which can be considered to be a major contributio... This paper studied the contact stresses in curvic attachments.The principal purpose of this research is to employ a method of alleviating the fluctuating hoop stresses which can be considered to be a major contribution to fatigue failure in curvic attachments.This method entails novel precision geometry of the contacting flat on curvic which is a tactic to get appropriate arc heights in in-plane direction as well as vary radius in out-of-plane direction.The dimensional finite elements in both directions were analyzed.These analysis results indicated that significant reduction in fluctuating hoop stresses can be achieved by the proposed method,provided that the precision geometry is controlled sufficiently precisely. 展开更多
关键词 curvic attachments stress analysis finite element analysis
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Exploring the Association between Adult Attachment Styles in Romantic Relationships, Perceptions of Parents from Childhood and Relationship Satisfaction 被引量:1
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作者 Gwen Gleeson Amanda Fitzgerald 《Health》 2014年第13期1643-1661,共19页
Little research has examined how attachment styles in childhood are related to current romantic relationship experiences. The aim of this study was to explore the association between perceptions of childhood experienc... Little research has examined how attachment styles in childhood are related to current romantic relationship experiences. The aim of this study was to explore the association between perceptions of childhood experiences with parents, attachment styles in romantic relationships, and relationship satisfaction in a sample of young adults. The sample consisted of 227 participants, 153 of which were university students and the remaining 69 were members of the general population. Of these, 177 (78%) were female and 50 (22%) were male, with an age range of 18 - 39. Participants completed a battery of self-report measures assessing their attachment style in romantic relationships, satisfaction in their current romantic relationship, and an adjective checklist describing their parents and their parent’s relationship with each other. The majority of males had an avoidant-fearful style, while females tended to have an avoidant-fearful or secure style. Findings were that participants’ descriptions of their mother, father, and parental relationship were associated with their attachment style. In terms of a current romantic relationship, those with a secure attachment style were much more likely to be in a relationship whereas those with an avoidant-fearful style were not. Secure participants were more satisfied in their relationships than the insecure styles of attachment. Finally, chi-square tests revealed that there was no association between gender and attachment style. Results were discussed in terms of methodological limitations such as the use of self-report measures;theoretical weaknesses for example the variability in the approaches used in attachment research;and future research, which included the use of longitudinal studies which may offer insight into how early parenting behaviours act as predictors of later relationship functioning. 展开更多
关键词 Adult attachment ROMANTIC Relationships Relationship SATISFACTION CHILDHOOD
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Sufficiently diffused attachment of nitrogen arc by gasdynamic action 被引量:1
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作者 Wenxia Pan Lewen Chen +2 位作者 Xian Meng Yong Zhang Chengkang Wu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第6期293-296,共4页
For realizing diffused anode attachment in pure nitrogen arcs, a special arc plasma generator was designed and combined with suitable working parameters such as gas flow rate and arc current. The anode has a flow-rest... For realizing diffused anode attachment in pure nitrogen arcs, a special arc plasma generator was designed and combined with suitable working parameters such as gas flow rate and arc current. The anode has a flow-restrictor channel of 2.8 mm diameter and downstream expansion half-angle of 8°, with the purpose of creating a dispersed nitrogen-arc column by strong gasdynamic expansion effect. Results show that, when thermal blocking condition existed in the flow restrictor and the cathode cavity pressure was higher than that in the exit chamber by at least 9 kPa, the action due to gasdynamic expansion could be much stronger than the self-magnetic contraction effect of the arc and the nitrogen arc column could be effectively dispersed to form a sufficiently diffused attachment on the water-cooled anode surface. 展开更多
关键词 Pure nitrogen arc Diffused arc root attachment Gas dynamic expanding action Arc channel structure Working parameter
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Adaptive Wall-Based Attachment Ventilation:A Comparative Study on Its Effectiveness in Airborne Infection Isolation Rooms with Negative Pressure 被引量:2
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作者 Ying Zhang Ou Han +4 位作者 Angui Li Li’an Hou Thomas Olofsson Linhua Zhang Wenjun Lei 《Engineering》 SCIE EI 2022年第1期130-137,共8页
The transmission of coronavirus disease 2019(COVID-19)has presented challenges for the control of the indoor environment of isolation wards.Scientific air distribution design and operation management are crucial to en... The transmission of coronavirus disease 2019(COVID-19)has presented challenges for the control of the indoor environment of isolation wards.Scientific air distribution design and operation management are crucial to ensure the environmental safety of medical staff.This paper proposes the application of adaptive wall-based attachment ventilation and evaluates this air supply mode based on contaminants dispersion,removal efficiency,thermal comfort,and operating expense.Adaptive wall-based attachment ventilation provides a direct supply of fresh air to the occupied zone.In comparison with a ceiling air supply or upper sidewall air supply,adaptive wall-based attachment ventilation results in a 15%–47%lower average concentration of contaminants,for a continual release of contaminants at the same air changes per hour(ACH;10 h^(-1)).The contaminant removal efficiency of complete mixing ventilation cannot exceed 1.For adaptive wall-based attachment ventilation,the contaminant removal efficiency is an exponential function of the ACH.Compared with the ceiling air supply mode or upper sidewall air supply mode,adaptive wall-based attachment ventilation achieves a similar thermal comfort level(predicted mean vote(PMV)of0.1–0.4;draught rate of 2.5%–6.7%)and a similar performance in removing contaminants,but has a lower ACH and uses less energy. 展开更多
关键词 Ventilation efficiency Air change rate COVID-19 attachment ventilation Air distribution Isolation ward
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Effect of the surface microstructure of arsenopyrite on the attachment of Sulfobacillus thermosulfidooxidans in the presence of dissolved As(Ⅲ) 被引量:1
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作者 Zhen Xue Zhen-yuan Nie +6 位作者 Hong-chang Liu Wei-bo Ling Qian Pan Jin-lan Xia Lei Zheng Chen-yan Ma Yi-dong Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第7期1135-1144,共10页
Understanding bacterial adsorption and the evolution of biofilms on arsenopyrite with different surface structures is of great signific-ance to clarifying the mechanism of microbe-mineral interfacial interactions and ... Understanding bacterial adsorption and the evolution of biofilms on arsenopyrite with different surface structures is of great signific-ance to clarifying the mechanism of microbe-mineral interfacial interactions and the production of acidic mine drainage impacting the environ-ment.In this study,the attachment of Sulfobacillus thermosulfidooxidans cells and subsequent biofilm formation on arsenopyrite with different surface structures in the presence of dissolved As(Ⅲ)was studied.Arsenopyrite slices with a specific surface were obtained by electrochemic-al corrosion at 0.26 V.The scanning electronic microscopy-energy dispersion spectra analyses indicated that the arsenopyrite surface deficient in sulfur and iron obtained by electrochemical treatment was not favorable for the initial adsorption of bacteria,and the addition of As(Ⅲ)in-hibited the adsorption of microbial cells.Epifluorescence microscopy showed that the number of cells attaching to the arsenopyrite surface in-creased with time;however,biofilm formation was delayed significantly when As(Ⅲ)was added. 展开更多
关键词 ARSENOPYRITE surface microstructure BIOLEACHING sulfobacillus thermosulfidooxidans attachment behaviors
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Numerical simulation of the effects of protrusion on DC arc anode attachment 被引量:1
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作者 牛冲 孟显 +3 位作者 黄河激 朱涛 孙素蓉 王海兴 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第10期49-59,共11页
The attachment of the DC arc on the anode is usually affected by surface morphology such as protrusions due to ablation or melting deformation.A three-dimensional thermodynamic and chemical non-equilibrium model is us... The attachment of the DC arc on the anode is usually affected by surface morphology such as protrusions due to ablation or melting deformation.A three-dimensional thermodynamic and chemical non-equilibrium model is used to numerically simulate the effect of artificially assumed surface protrusions on the arc anode attachment.The numerical simulation results show that the arc deflects toward the protrusions on the anode and attaches to them in a constricted mode,resulting in an increase in the temperature of the arc attachment region.The analysis shows that the presence of protrusion on the anode surface changes the electric field distribution,intensifies the degree of thermodynamic and chemical non-equilibrium in its vicinity,further influences the chemical kinetic process of the plasma around it,which is the main reason for the deflection of the arc toward the protrusions and the arc anode attachment in a constricted mode.In order to verify the numerical simulation results,verification experiments are also performed using similar size scale anode protrusion,and the results showed that the presence of protrusion can indeed cause the deflection of the arc and even cause the ablation of the protrusion. 展开更多
关键词 DC arc arc anode attachment anode protrusion chemical non-equilibrium
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