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Home Mealtimes in Kenya and Zambia:Recognising culturally grounded practices that foster healthy eating behaviours
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作者 Jeofrey Mtemeri Hetal Patel +7 位作者 Rehema Abiyo Claire Farrow Megan Jarman Haatembo Mooya Laura Shapiro Barnabas Simatende Pamela Wadende Henriette Zeidler 《Journal of Psychology in Africa》 2026年第1期53-63,共11页
Globally,mealtimes provide key insights into cultural and social values and practices.We examine mealtime environments and eating practices in two different African settings using quantitative observational and questi... Globally,mealtimes provide key insights into cultural and social values and practices.We examine mealtime environments and eating practices in two different African settings using quantitative observational and questionnaire data.Participating families(N=80)were recruited from two rural locations in Zambia and Kenya.Results following descriptive analysis showed that meals are typically taken as a family in a sociable context,providing opportunities to nurture children’s positive behaviours.In both communities,mothers(71.25%)were most likely to be present and typically prepared meals and provided the food.We observed a few distractions being used during mealtimes,and children finished their food with little to no conflict.Plate sharing varied across the two sites and was more common in Zambia,where we also observed more traditional practices such as eating with hands(as opposed to cutlery)and sitting on mats on the ground(as opposed to seated on chairs or sofas).Overall,our findings suggest more similarities in the cultural and social values across the two African contexts despite slight differences in mealtime practices.In particular,positive mealtime behaviours(little food refusal,lack of conflict)were common across all contexts,regardless of the extent to which traditional practices(such as plate-sharing and sitting on the floor)were used.Findings align with Family Systems theory,which states that the family is understood best by conceptualizing it as a complex,dynamic,and changing collection of parts,subsystems,and family members. 展开更多
关键词 Detractors LUNCH parent-child interaction eating behaviour feeding practices
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Smallholder farmers' intention to adopt Climate-Smart Agricultural(CAS) practices: Insights into the socio-psychological dimensions of their pro-environmental behaviours
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作者 Dash Baishakhy SMITA Speelman STIJN 《Regional Sustainability》 2026年第2期75-94,共20页
Although various Climate-Smart Agricultural(CSA) practices are promoted to safeguard agricultural production and food security in the Global South,their adoption remains limited.This study conducted a cross-sectional ... Although various Climate-Smart Agricultural(CSA) practices are promoted to safeguard agricultural production and food security in the Global South,their adoption remains limited.This study conducted a cross-sectional survey using a semi-structured questionnaire between March and April in 2023,with a sample of 231 smallholder farmers covering 5 villages(Purbo Karpara,Rampasa,Monohor Pur,Boro Isubpur,and Char Alapur) in Haor wetlands of Bangladesh.Then,this study examined smallholder farmers' adoption intention of floating farming practice in Haor wetlands of Bangladesh based on an extended Theory of Planned Behaviour(TPB) model.The result demonstrated moderate predictive power of the proposed model,where farmers' attitude,subjective norm,knowledge of floating farming practice,perceived behavioural control,and institutional accessibility jointly explained 11.50% of the total variance in adoption intention,with subjective norm and perceived behavioural control showing significant impact on smallholder farmers' adoption intention.However,key barriers reported by smallholder farmers included unavailability of resources,limited access to modern farming practices,input and credit unavailability,insufficient access to training,and limited access to market system.These findings indicated that improving smallholder farmers' access to extension services and credit facilities,raising awareness,providing training,and guaranteeing access to accurate and timely climate information and early warning systems could significantly improve their adaptive capacity.This study contributes to socio-psychological understanding of smallholder farmers' pro-environmental behaviour and emphasises the need for context-specific interventions to support sustainable livelihoods and resilient agri-food systems in climate-vulnerable regions. 展开更多
关键词 Climate-Smart Agricultural(CSA)practices Theory of Planned Behaviour(TPB) Partial Least Square Structural Equation Modeling(PLS-SEM) Pro-environmental behaviour Food security Haor wetlands
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Preschool-aged children 24-hour movement behaviours before and during COVID-19
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作者 Mingming Cui Xiaojuan Wang +5 位作者 Zhaoxu Lu Anthony D.Okely Katharina Kariippanon Ellie K.Taylor Ting Zhang Hongyan Guan 《Sports Medicine and Health Science》 2025年第4期249-255,共7页
The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)affected health,economies,and lifestyles,but little is known about its impact on children.We aimed to... The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)affected health,economies,and lifestyles,but little is known about its impact on children.We aimed to investigate changes in 24-hour(h)movement behaviours of pre-school children before and during COVID-19,and factors that influenced these.Children aged 3-6 years were recruited in Beijing in 2019,and their movement behaviours over 24h assessed by questionnaire,as part of the International Study of Movement Behaviors in the Early Years(SUNRISE)study.We conducted the survey again during COVID-19,and compared the children’s movement behaviours before and during COVID-19 and associated factors.Overall,196 parents completed the survey at both time points.The percentage of children meeting movement guidelines decreased during the pandemic(p<0.01).Total physical activity decreased less among children getting good quality sleep or with more adults in the household(p<0.01).Children who were not cared for primarily by their mother had a greater decrease in moderate to vigorous intensity physical activity(p=0.02),but the decrease was smaller among children whose parents used the internet to support their physical activity and/or screen time(p<0.05).Children who used electronic screen devices in the 2h before bedtime or whose parents reported body temperature in webchats had a greater increase in sedentary screen time(p<0.05).Children spending more time outdoors showed a smaller decrease in sleep(p<0.01).Overall,children’s movement behaviours changed significantly during the pandemic. 展开更多
关键词 24-H movement behaviours Physical activity Sedentary screen time SLEEP CHILDREN COVID-19 pandemic
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Objectively measured 24-h movement behaviours of child-guardian pairs in low-to-middle income households in Nairobi City County,Kenya
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作者 Lucy-Joy Wachira Nils Swindell +9 位作者 Noora Kanerva Muhoro Munuhe Timo Vuorimaa Tiina Laiho Sophie Ochola Maijaliisa Erkkola George Owino Gareth Stratton Mikael Fogelholm Vincent Onywera 《Sports Medicine and Health Science》 2025年第4期263-271,共9页
Background The decreasing prevalence of physical activity(PA)among urban children in Sub-Saharan Africa is a growing public health concern.More emphasis should focus on examining the influence of parental PA behaviour... Background The decreasing prevalence of physical activity(PA)among urban children in Sub-Saharan Africa is a growing public health concern.More emphasis should focus on examining the influence of parental PA behaviour on the children’s PA patterns.We explored associations of 24hour(h)accelerometer-measured movement behaviours of guardian-child pairs in Nairobi City County,Kenya.Methods This cross-sectional study assessed 80 pairs consisting of children aged 9-14 years and their guardians in one area of low and one area of middle socioeconomic status(SES)(Embakasi Sub-County and Lang’ata Sub-County),in Nairobi City County,Kenya.The study used waist worn Tri-axial Actigraph(GT3X+and ActiSleep+)accelerometers to quantify PA and sedentary time(SED).Association between guardians'and children’s PA was examined using linear regression,adjusting for guardians'educational attainment and household wealth.Results Of the children,42(52.5%)and 76(96.2%)of the guardians were women.Children in low SES areas spent more time(p<0.001)in moderate-to-vigorous physical activity compared to children from middle SES area.The guardians in low SES area were younger and spent more time in light PA(p=0.036)while their counterparts had higher daily SED(p=0.049).Guardian’s SED associated with higher children’s SED(p=0.033)even after adjusting for guardians'educational attainment(p=0.032)and wealth(p=0.05).There was no association between guardians'and children’s MVPA.Conclusion Considered alongside the extant literature,these results suggest that health promotion strategies should aim to reduce parental SED time while also planning to increase children’s PA. 展开更多
关键词 24-h movement behaviour Accelerometer Adolescents PARENT Physical activity Socio-economic status
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Precise modulation of the debonding behaviours of ultra-thin wafers by laser-induced hot stamping effect and thermoelastic stress wave for advanced packaging of chips
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作者 Jieyuan Zhang Yanlei Hu +6 位作者 Fangcheng Wang Qiang Liu Fangfang Niu Jinhui Li Mingqi Huang Guoping Zhang Rong Sun 《International Journal of Extreme Manufacturing》 2025年第1期395-407,共13页
Laser debonding technology has been widely used in advanced chip packaging,such as fan-out integration,2.5D/3D ICs,and MEMS devices.Typically,laser debonding of bonded pairs(R/R separation)is typically achieved by com... Laser debonding technology has been widely used in advanced chip packaging,such as fan-out integration,2.5D/3D ICs,and MEMS devices.Typically,laser debonding of bonded pairs(R/R separation)is typically achieved by completely removing the material from the ablation region within the release material layer at high energy densities.However,this R/R separation method often results in a significant amount of release material and carbonized debris remaining on the surface of the device wafer,severely reducing product yields and cleaning efficiency for ultra-thin device wafers.Here,we proposed an interfacial separation strategy based on laser-induced hot stamping effect and thermoelastic stress wave,which enables stress-free separation of wafer bonding pairs at the interface of the release layer and the adhesive layer(R/A separation).By comprehensively analyzing the micro-morphology and material composition of the release material,we elucidated the laser debonding behavior of bonded pairs under different separation modes.Additionally,we calculated the ablation threshold of the release material in the case of wafer bonding and established the processing window for different separation methods.This work offers a fresh perspective on the development and application of laser debonding technology.The proposed R/A interface separation method is versatile,controllable,and highly reliable,and does not leave release materials and carbonized debris on device wafers,demonstrating strong industrial adaptability,which greatly facilitates the application and development of advanced packaging for ultra-thin chips. 展开更多
关键词 laser debonding behaviours laser-induced hot stamping effect thermoelastic stress wave advanced packaging
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500 MPa级低合金高强钢组织与拉伸行为的各向异性研究
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作者 王朝斌 穆振凯 +6 位作者 张士杰 聂强胜 安方亮 姜军 王硕康 刘石双 周纪名 《材料导报》 北大核心 2026年第3期213-219,共7页
本工作主要研究了汽车结构件用500 MPa级低合金高强钢组织和拉伸行为的各向异性。利用扫描电子显微镜、拉伸试验机等设备研究了CR500LA合金与轧制方向分别成0°、45°和90°试样的组织、织构、拉伸性能和断裂行为,采用Hill... 本工作主要研究了汽车结构件用500 MPa级低合金高强钢组织和拉伸行为的各向异性。利用扫描电子显微镜、拉伸试验机等设备研究了CR500LA合金与轧制方向分别成0°、45°和90°试样的组织、织构、拉伸性能和断裂行为,采用Hill48-σ、Hill48-r和Yld2000-2d屈服准则对CR500LA合金的各向异性进行了预测。结果表明:合金主要由铁素体和珠光体组成,织构类型主要有{111}〈110〉、{111}〈112〉、{001}〈110〉、{112}〈110〉,其中α纤维织构{112}〈110〉占主导;随着与轧制方向夹角的增加,拉伸强度呈先下降后上升的趋势,塑性和r值呈先上升后下降的趋势;合金的各向异性主要是由织构类型和比例差异而引起;Yld2000-2d屈服模型对CR500LA合金各向异性的预测更精准;拉伸断口为典型的由大量韧窝组成的韧性断裂。 展开更多
关键词 低合金高强钢 CR500LA 显微组织 拉伸行为 各向异性
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高血压患者8年就医行为轨迹及影响因素分析
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作者 吴春香 田婕 +4 位作者 郭毅 邓波 于杰 蔡宁 沈莉 《中国全科医学》 北大核心 2026年第13期1660-1665,1681,共7页
背景 高血压已逐渐成为危害人民健康、影响人们生活质量的主要疾病,由于高血压具有病程长、并发症多、基本不可治愈等特点,患者需要长期就医。掌握高血压患者就医行为长期变化趋势及其影响因素情况,对于制订高血压精准防控策略和开展健... 背景 高血压已逐渐成为危害人民健康、影响人们生活质量的主要疾病,由于高血压具有病程长、并发症多、基本不可治愈等特点,患者需要长期就医。掌握高血压患者就医行为长期变化趋势及其影响因素情况,对于制订高血压精准防控策略和开展健康服务具有重要意义。目的 通过对社区管理的高血压患者长期就医行为进行群组轨迹拟合,掌握人群的就医行为轨迹,分析其特征和行为转变因素,为高血压防治政策提供依据。方法 选取自2014年开始在社区健康档案中有连续记录的8 922例高血压患者为研究对象,通过居民个人电子健康档案系统收集2014—2021年的就诊信息和随访管理信息,采用群组轨迹模型(GBTM)分析患者就医行为改变模式,模拟不同分组行为的转变,匹配出最佳行为轨迹模型;采用方差分析和χ^(2)检验比较不同行为轨迹之间的患者特征;以持续不规律就医组为对照组,采用多因素Logistic回归分析各轨迹组之间的影响因素。结果 共收集8 922例高血压患者的门诊就诊信息共计444 126条,GBTM拟合结果显示,将就医行为轨迹拟合为5组的模型为最佳,分别为持续规律组(39.84%)、规律缓慢下降组(25.36%)、规律U型变化组(11.43%)、规律缓慢上升组(11.86%)和持续不规律组(14.86%);5组患者性别、年龄、高血压病程、糖尿病史、脑缺血短暂发作史和高血压家族史、规律运动情况比较,差异有统计学意义(P<0.05);以持续不规律就医组为参考,性别、年龄、高血压病程、家族史、糖尿病史和短暂性脑缺血发作史都是就医规律性模式转变的影响因素(P<0.05)。女性和年龄≥75岁患者容易从持续不规律的就医行为转变为持续规律就医或者早期规律就医行为,糖尿病和短暂性脑缺血发作的患者表现为持续不规律就医行为的比值比更低;高血压病程的延长和家族史不利于就医行为模式的转变。结论 高血压患者的规律就医行为还需长期关注,坚持长期规律就医行为的患者低于40%;对于女性、≥75岁以上、伴有糖尿病或者短暂性脑缺血发作的患者,适当的管理措施容易促使规律就医行为的转变和维持;对于其他类型患者需继续开展分析研究,寻找行为转变的关键因素,促使行为转变的发生。 展开更多
关键词 高血压 就医行为 行为轨迹 规律就医 行为转变 影响因素分析
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不同溶氧环境对许氏平鲉幼鱼群体行为、生长和生理的影响
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作者 张正 赵婧思 +4 位作者 田涛 于晓明 邢彬彬 殷雷明 吴忠鑫 《渔业现代化》 北大核心 2026年第1期74-83,共10页
为探究许氏平鲉(Sebastes schlegelii)幼鱼对不同溶氧环境的反应,选取平均体质量0.520±0.130g的许氏平鲉幼鱼,设置3、5、7(对照组)、10 mg/L溶氧含量处理组,试验周期28 d,观察分析了不同溶氧水平对许氏平鲉幼鱼运动行为、生长性能... 为探究许氏平鲉(Sebastes schlegelii)幼鱼对不同溶氧环境的反应,选取平均体质量0.520±0.130g的许氏平鲉幼鱼,设置3、5、7(对照组)、10 mg/L溶氧含量处理组,试验周期28 d,观察分析了不同溶氧水平对许氏平鲉幼鱼运动行为、生长性能及血液生化的影响。结果显示:随着水体溶氧含量的增加,试验鱼的自发游泳速度、个体间距离、最近邻距离显著增大(P<0.05),且均在10 mg/L溶氧水平时达到最高,凝聚力、协调性及极性逐渐减小;当水体溶氧含量不断增加时,许氏平鲉幼鱼的存活率、特定生长率、饲料转化率、肝体比及脏体比这几项指标,均表现出显著提升的趋势(P<0.05),且均在10 mg/L组时达到最大;随着水体溶氧含量的增加,鱼体血液中总蛋白、总胆固醇、甘油三酯含量逐渐升高;葡萄糖、谷丙转氨酶含量先降低后持续稳定;谷草转氨酶含量先降低后升高。结果表明,低氧胁迫会影响许氏平鲉的行为以及生理指标,并造成许氏平鲉生长缓慢。 展开更多
关键词 溶氧 许氏平鲉 生长 群体行为 生理
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药学实践研究常用行为理论及模型的范围综述
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作者 蒋文婷 施爱明 +3 位作者 陆浩 高雯 张宏亮 潘杰 《医药导报》 北大核心 2026年第3期481-488,共8页
目的系统梳理行为理论和模型在药学实践研究中的应用现状,总结其应用特点、作用与价值。方法采用范围综述法,检索Web of Science、PubMed、Embase、Cochrane Library及中国知网、万方数据库、维普中文科技期刊数据库、中国生物医学数据... 目的系统梳理行为理论和模型在药学实践研究中的应用现状,总结其应用特点、作用与价值。方法采用范围综述法,检索Web of Science、PubMed、Embase、Cochrane Library及中国知网、万方数据库、维普中文科技期刊数据库、中国生物医学数据库中所有使用行为理论或模型的药学实践相关文章,检索期限为建库至2025年3月31日。由2名研究者独立对纳入的文献数据进行汇总、筛选、归类及分析。结果共检索到文献1669篇,最终纳入110篇。通过文献分析,提取出药学实践中5个高频使用理论模型,依次为计划行为理论(TPB)、跨理论模型(TTM)、行为改变理论(COM-B)、健康信念模型(HBM)、社会认知理论(SCT),国内外药学实践研究常用理论模型及围绕主题存在一定差异。大多数研究采用单一理论模型,国内外最常见的组合分别是TPB与TTM、COM-B与理论领域框架(TDF)。研究多属于英国医学研究委员会(UK MRC)复杂干预研究框架中的前2个阶段。国外研究人员主要为药学人员及卫生管理部门,而我国主要为护理人员,其次为药学人员。结论我国药学实践研究尚处于起步阶段,有必要借鉴国际经验,明确研究问题并选择合适的理论模型,提高药学服务有效性和可持续性的同时提高研究的科学性和实用性,推动国内药学实践研究的发展。 展开更多
关键词 药学实践研究 行为理论 模型 范围综述法
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浸水深度对煤岩力学损伤行为的影响及多尺度失稳机制研究
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作者 陈光波 郑绍黄 +8 位作者 张俊文 李谭 王二雨 王创业 刘业娇 曹健 张国华 唐薇 高宁 《采矿与岩层控制工程学报》 北大核心 2026年第1期121-143,共23页
大水矿山或富水开采条件下,不同浸水深度环境中煤岩体力学性质严重劣化,影响着煤岩系统的安全稳定。为探讨在不同浸水深度下煤岩力学性质及损伤特征,以典型的煤、砂岩和页岩为研究对象,开展0、20、40、60、80、100 mm等6种不同浸水深度... 大水矿山或富水开采条件下,不同浸水深度环境中煤岩体力学性质严重劣化,影响着煤岩系统的安全稳定。为探讨在不同浸水深度下煤岩力学性质及损伤特征,以典型的煤、砂岩和页岩为研究对象,开展0、20、40、60、80、100 mm等6种不同浸水深度下的轴向压缩和声发射试验,分析其力学损伤及失稳机制。研究结果表明:①随浸水深度的增加,煤岩弹性模量、损伤应力和抗压强度逐渐降低,煤岩弹性模量、抗压强度劣化度显著增加,在浸水0~20 mm阶段劣化效应最大。②随浸水深度的增加,声发射累计振铃计数和峰值振铃计数逐渐减少;累计能量受浸水深度影响逐渐降低。③基于声发射RA-AF,不同浸水深度砂岩试样张拉裂纹与剪切裂纹共存,随浸水深度的增加,张拉裂纹占比逐渐增大,剪切裂纹占比逐渐减小。④基于声发射构建煤岩损伤演化模型,从应力–应变曲线、损伤效应、抗压强度三方面进行损伤模型合理性验证。煤岩损伤演化过程可划分为损伤初始阶段、损伤发展阶段和损伤加速阶段,随浸水深度的增加,煤岩损伤变量增加。⑤从“微观–细观–宏观”阐明浸水煤岩多尺度失稳破坏机制:浸水作用下煤岩内部矿物颗粒被溶蚀,矿物颗粒体积减小,载荷作用下矿物颗粒发生微断裂、大断裂、全断裂,煤岩内部萌生新的裂纹并扩展、贯通,宏观上出现裂纹,煤岩失稳破坏。该研究可为浸水深度影响下工程煤岩体的安全稳定、防治及评价提供有益参考。 展开更多
关键词 浸水深度 力学行为 声发射 损伤模型 失稳机制
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基于油水界面行为解析肌原纤维蛋白基乳液稳定机制及其在食品中的应用进展
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作者 陈玉峰 杨方东 +6 位作者 洪晴雨 程威威 郑雅丹 史慧茹 周绪霞 丁玉庭 刘书来 《食品与发酵工业》 北大核心 2026年第1期387-398,共12页
肌原纤维蛋白(myofibrillar protein,MP)是肉类蛋白的主要成分,其两亲性是构建乳液体系的良好材料。然而,MP乳液受限于离子强度和结构特性,易发生絮凝和聚集。因此,改善MP油水界面特性尤为重要。尽管不同改性方法已被用于改善MP的油水... 肌原纤维蛋白(myofibrillar protein,MP)是肉类蛋白的主要成分,其两亲性是构建乳液体系的良好材料。然而,MP乳液受限于离子强度和结构特性,易发生絮凝和聚集。因此,改善MP油水界面特性尤为重要。尽管不同改性方法已被用于改善MP的油水界面特性,但尚未形成全面总结,且关于MP基乳液的油水界面稳定性机制仍需进一步系统综述。该文全面总结了MP油水界面特性改善方法(物理法、化学法和物理化学联合法)。详细综述了单独MP、MP-多酚和MP-多糖稳定的Pickering乳液和乳液凝胶,以及单独MP稳定的纳米乳液在油水界面稳定机制,并介绍了MP基乳液在食品工业中的应用,以期为开发更稳定和多功能应用的MP乳液提供参考。 展开更多
关键词 肌原纤维蛋白 改性技术 稳定性 油水界面行为 食品工业
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儿童困难问题和亲社会行为在家庭弹性与祖辈隔代教养压力间的中介作用
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作者 王悦祺 宋东玉 +2 位作者 李玉丽 谢昊 张月蓉 《山东大学学报(医学版)》 北大核心 2026年第1期57-64,共8页
目的探讨儿童困难问题和亲社会行为在家庭弹性与祖辈隔代教养压力间的中介作用。方法采用家庭弹性评定量表、祖父母教养压力量表、长处和困难问卷(父母版)对247位参与协同教养的祖辈进行调查。使用AMOS 24.0软件构建结构方程模型,采用Bo... 目的探讨儿童困难问题和亲社会行为在家庭弹性与祖辈隔代教养压力间的中介作用。方法采用家庭弹性评定量表、祖父母教养压力量表、长处和困难问卷(父母版)对247位参与协同教养的祖辈进行调查。使用AMOS 24.0软件构建结构方程模型,采用Bootstrap法进行中介效应检验。结果家庭弹性与隔代教养压力和儿童困难问题之间呈负相关(r=-0.22、r=-0.26,均P<0.01),与儿童亲社会行为呈正相关(r=0.16,P<0.05);儿童困难问题与隔代教养压力呈正相关(r=0.39,P<0.01),儿童亲社会行为与隔代教养压力呈负相关(r=-0.32,P<0.01)。儿童困难问题在家庭弹性与祖辈隔代教养压力间起中介作用,中介效应为-0.668,占总效应的48.94%。儿童亲社会行为在家庭弹性与祖辈隔代教养压力间起部分中介作用,中介效应为-0.268,占总效应的19.43%。结论家庭弹性不仅可以直接降低祖辈隔代教养压力,还可以通过减少儿童困难问题、增加儿童亲社会行为,间接缓解祖辈隔代教养压力。 展开更多
关键词 祖父母 隔代教养压力 家庭弹性 儿童困难问题 儿童亲社会行为
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链式产业集群企业安全生产不良行为形成机理研究
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作者 徐恒婕 梅强 +1 位作者 刘素霞 张菁菁 《管理评论》 北大核心 2026年第1期39-50,共12页
近年来,链式产业集群内发生的安全生产重大责任事故表明安全生产不良行为问题严重,对其进行治理是一项复杂的系统工程,需要充分考虑链式集群安全生产的特殊性,因此,要从明晰链式集群企业安全生产不良行为的形成机理着手研究。本研究通... 近年来,链式产业集群内发生的安全生产重大责任事故表明安全生产不良行为问题严重,对其进行治理是一项复杂的系统工程,需要充分考虑链式集群安全生产的特殊性,因此,要从明晰链式集群企业安全生产不良行为的形成机理着手研究。本研究通过深度访谈,应用扎根理论研究方法,结合行为决策理论,构建了多主体参与的链式集群企业安全生产不良行为形成机理模型,探讨各主体职责与影响机制。模型涵盖了主要的参与主体:政府安监部门、安全生产服务机构、社会公众及媒体、链式集群管理方、中小企业和龙头企业。研究结果表明,各主体在自身行为逻辑下,受不同的个体因素和环境因素影响,均形成消极的行为策略;各主体交互影响,最终形成链式集群企业安全生产不良行为。最后,根据形成机理提出了治理策略,从改善政府安监部门懈怠执法、敷衍服务的行为策略着手,并配合多种手段调动链式集群内外主体参与安全生产治理的积极性,促进政府从单一治理向引导多主体治理转变,最终实现良性互动。 展开更多
关键词 链式产业集群 安全生产 不良行为 形成机理 扎根理论
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冷弯薄壁型钢六肢拼合截面柱轴压性能研究
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作者 赵阳 聂少锋 +3 位作者 周天华 刘向斌 桑刘睿 王旭东 《建筑科学与工程学报》 北大核心 2026年第2期42-50,共9页
为研究冷弯薄壁型钢六肢拼合截面柱的轴压性能,对12根六肢拼合截面冷弯薄壁型钢柱进行轴压试验研究,得到了试件的荷载-轴向位移曲线、荷载-柱中挠度曲线、荷载-应变曲线和极限承载力,并分析了试件的屈曲模式和破坏模式。利用有限元分析... 为研究冷弯薄壁型钢六肢拼合截面柱的轴压性能,对12根六肢拼合截面冷弯薄壁型钢柱进行轴压试验研究,得到了试件的荷载-轴向位移曲线、荷载-柱中挠度曲线、荷载-应变曲线和极限承载力,并分析了试件的屈曲模式和破坏模式。利用有限元分析软件ANSYS建立六肢拼合柱的精细化有限元模型,并以此为基础开展系统性研究,探究长细比、腹板高厚比等参数对拼合柱力学性能的影响规律。结果表明:轴压短柱试件的屈曲模式主要为局部-畸变相关屈曲,轴压长柱试件的主要破坏模式为局部-畸变-整体相关屈曲;拼合柱试件的极限承载力与刚度均随其长细比及腹板高厚比的增大而减小;当长细比从18.0增至216.7(90系列)及从12.4增至221.1(140系列)时,极限承载力分别下降81.76%与82.71%;腹板高厚比由46.0增至115.0(90系列)及由71.5增至178.8(140系列)时,不同长度试件的承载力降幅达63.0%~88.0%。 展开更多
关键词 冷弯薄壁型钢 六肢拼合柱 试验研究 轴压性能
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Bubble and flow characteristics in EAF with multi-mode bottom blowing
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作者 Xing-Yu Liu Xiao-Yu Guo +4 位作者 Li-Hui Han Liang Ren Gui-Bin Jia Wei Yan Jing Li 《Journal of Iron and Steel Research International》 2026年第1期374-397,共24页
Understanding the bubble behaviours and flow characteristics of large-capacity bottom-blowing electric arc furnace(EAF)is crucial for potential exogenous gas-induced slag foaming process and enhancement of molten bath... Understanding the bubble behaviours and flow characteristics of large-capacity bottom-blowing electric arc furnace(EAF)is crucial for potential exogenous gas-induced slag foaming process and enhancement of molten bath dynamics.A physical model and a 3D gas-slag-steel transient bottom-blowing numerical model of a 150 t EAF were established to investigate the bubble behaviour and flow characteristics throughout the molten steel bath and slag layer under bottom-blowing,with referring to gas flow rate,plug diameter,plug arrangement and injection angle.Results indicate that the average bubble sizes experience increase,dynamic stability and decrease in molten steel bath and then undergo decrease and increase after entering into slag layer for all bottom-blowing modes.The bubble numbers exhibit the opposing trends during the process.Increase in gas flow rate leads to a significant rise in average bubble size but a decrease in number,average dwelling time and the spread area of bubbles in slag layer.Increase in plug diameter causes an opposite impact.The effect of plug arrangement radii on bubbles is almost negligible.Increasing the injection angle results in an increase in bubble size and a decrease in both bubble number and dwelling time in slag layer.The slag foaming potential was discussed referring to the bubble size,number and dwelling time in slag layer.Increase in gas flow rate and plug diameters can significantly enhance the fluids flow through increasing average flow velocity,decreasing mixing time and dead zone ratio of molten bath.Plug arrangement radius and injection angle express nonlinear correlation with average flow velocity and dead zone ratio,and the plug arrangement radius of 0.5R(R represents the radius of bottom circle of EAF model)and injection angle of 15°perform better in enhancing dynamics of molten bath.A group of bottom-blowing parameters are proposed to achieve better comprehensive performance of bubble-induced slag foaming and molten bath dynamics. 展开更多
关键词 EAF Bubble behaviour Flow characteristics Bottom blowing Numerical model
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Semi-supervised Risk Assessment Research for Intelligent Vehicles Inspired by Collective Biological Risk-avoidance Behaviors
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作者 Hongyu Hu Zhonghua Xiong +2 位作者 Zhengyi Li Tianjun Sun Rui Ran 《Journal of Bionic Engineering》 2026年第1期225-238,共14页
To address the critical challenge of risk perception and assessment for autonomous vehicles in dynamic interactive envi-ronments,this study proposes a semi-supervised spatiotemporal interaction risk cognition network ... To address the critical challenge of risk perception and assessment for autonomous vehicles in dynamic interactive envi-ronments,this study proposes a semi-supervised spatiotemporal interaction risk cognition network with attention mecha-nism(SS-SIRCN),inspired by the behavioral adaptation patterns of biological groups under external threats.First,by thoroughly analyzing the dynamic interaction characteristics exhibited by typical biological collectives when exposed to risk,the study reveals the underlying patterns of trajectory changes influenced by external danger.Then,an attention-based spatiotemporal risk cognition network is designed to establish a mapping between driving behavior features and potential driving risks.Finally,a semi-supervised learning framework is employed to enable risk assessment for autono-mous vehicles using only a small amount of labeled data.Experimental results on real-world vehicle trajectory datasets demonstrate that the proposed method achieves a risk prediction accuracy of 90.76%,outperforming other baseline models in performance. 展开更多
关键词 Escape behaviour Predator avoidance Brain-like intelligent decision-making Attention mechanism Driving risk Automated driving
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Influence of CaO-SiO_(2)-Al_(2)O_(3)-MgO slag structure on dissolution behavior of Al_(2)O_(3):a molecular dynamics simulation
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作者 Yi-Hong Li Ming-Ming Lu +4 位作者 Rui Wang Dong Wang Xin Hu Peng Zhang Qiang Zhu 《Journal of Iron and Steel Research International》 2026年第1期110-124,共15页
The structural changes in the CaO-SiO_(2)-Al_(2)O_(3)-MgO slag system with varying CaO contents were investigated through molecular dynamics(MD)simulations,and its effect on the dissolution behavior of alumina inclusi... The structural changes in the CaO-SiO_(2)-Al_(2)O_(3)-MgO slag system with varying CaO contents were investigated through molecular dynamics(MD)simulations,and its effect on the dissolution behavior of alumina inclusions was characterized by the Kullback-Leibler(KL)divergence.The slag structure analysis revealed that the[AlO]tetrahedral structure was the primary network structure in the slag.With increasing the CaO content,the non-bridge oxygen(NBO)content in the slag structure increases,and the bridge oxygen(BO)content decreases,thereby reducing the complexity of the slag network structure.Raman spectroscopy detection verifies the results of the MD simulations.The results indicated that the dissolution rate of alumina inclusions accelerates with increasing the CaO content in the slag,owing to the reduced complexity of the slag network structure and the enhanced interatomic interactions.The simulation results for the dissolution of alumina inclusions were consistent with theoretical calculations based on the slag inclusion capacity and the dimensionless dissolution rate of inclusions.Radial distribution function analysis demonstrated that the interaction between atoms in the slag system and alumina inclusions strengthens,increasing the dissolution rate of alumina inclusions.The[AlO_(6)]octahedral structure of the alumina inclusions is disrupted,forming BO structures,which in turn enhances the complexity of the slag network structure,slowing the dissolution rate of alumina inclusions.In contrast,the slag system with a higher CaO content has a relatively simpler network structure,promoting faster alumina inclusion dissolution. 展开更多
关键词 Molecular dynamics simulation Slag structure Dissolution behaviour Alumina inclusion Dissolution rate
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冲刷速率与压力耦合作用对X70管线钢腐蚀行为的影响机制
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作者 覃祖安 任鹏炜 +2 位作者 唐兴颖 朱日广 陈积权 《材料导报》 北大核心 2026年第4期130-136,共7页
X70管线钢在深海的安全运行对海洋油气开发至关重要。自主设计并搭建了深海冲刷腐蚀反应装置,通过腐蚀失重实验、电化学测试、微观表征等测试方法,研究了深海环境(5 MPa)下X70管线钢的冲刷腐蚀行为以及耦合作用的腐蚀机制。结果表明,X7... X70管线钢在深海的安全运行对海洋油气开发至关重要。自主设计并搭建了深海冲刷腐蚀反应装置,通过腐蚀失重实验、电化学测试、微观表征等测试方法,研究了深海环境(5 MPa)下X70管线钢的冲刷腐蚀行为以及耦合作用的腐蚀机制。结果表明,X70管线钢在压力与冲刷耦合作用下,其腐蚀形貌为均匀腐蚀与点蚀相结合,且随着冲刷速率的升高,阻抗值降低,抗腐蚀性降低;腐蚀产物主要为γ-FeOOH、β-FeOOH、α-Fe_(2)O_(3)与Fe 3O 4,高压促进腐蚀,加快腐蚀产物的整体生长,冲刷促进α-Fe_(2)O_(3)和γ-FeOOH生成,阻碍β-FeOOH生成;高压与低冲刷速率耦合产生削弱作用,与高冲刷速率耦合则呈现加强作用,该过程的临界冲刷速率为2.25 m/s,临界冲击能为0.762 J。揭示了不同冲刷速率与深海压力耦合作用下X70管线钢的腐蚀行为及影响机制,为海底管线钢的腐蚀防护与寿命预测提供数据支撑与理论指导。 展开更多
关键词 X70管线钢 冲刷速率 压力 耦合作用 腐蚀行为
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