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人际关系和自我概念对生命意义的影响:一项追踪研究 被引量:27
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作者 张荣伟 Pual T.P.Wong 李丹 《心理科学》 CSSCI CSCD 北大核心 2020年第5期1154-1161,共8页
对1087名大学生进行为期1年的追踪研究,考察人际关系和自我概念对生命意义的影响,以及自我概念在人际关系与生命意义间的中介效应。结果显示:(1)人际关系、自我概念和生命意义之间存在同时性和继时性正相关;(2)在时间点1和时间点2,人际... 对1087名大学生进行为期1年的追踪研究,考察人际关系和自我概念对生命意义的影响,以及自我概念在人际关系与生命意义间的中介效应。结果显示:(1)人际关系、自我概念和生命意义之间存在同时性和继时性正相关;(2)在时间点1和时间点2,人际关系、自我概念和生命意义均两两相互预测;(3)人际关系和自我影响均影响生命意义,以及在人际关系与生命意义的关系中,自我概念起部分中介作用。即人际关系通过自我概念进而影响生命意义体验。结果表明,可以通过改善人际关系和提高自我概念来提升个体的生命意义感。即带着一颗自我肯定之心,积极参与到社会互动中去。 展开更多
关键词 人际关系 自我概念 生命意义 追踪研究 大学生
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多接收电感耦合等离子体质谱法高精密度测定汞同位素组成 被引量:26
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作者 尹润生 冯新斌 +3 位作者 Foucher Delphine 侍文芳 赵志琦 王静 《分析化学》 SCIE EI CAS CSCD 北大核心 2010年第7期929-934,共6页
采用多接收等离子体质谱(MC-ICP-MS)方法高精度测定了Hg同位素组成。本方法借助在线进样系统,最大程度上克服了同位素干扰和基体效应;采用同位素内标法和样品-标准交叉法以消除仪器自身的质量分馏;通过实验条件(如测定时间、进样量等)... 采用多接收等离子体质谱(MC-ICP-MS)方法高精度测定了Hg同位素组成。本方法借助在线进样系统,最大程度上克服了同位素干扰和基体效应;采用同位素内标法和样品-标准交叉法以消除仪器自身的质量分馏;通过实验条件(如测定时间、进样量等)的优化,方法的内精度显著提高。研究表明:为保证汞同位素组成的高精度测定,汞最低进样浓度为2μg/L时,内精度<0.02‰(RSD)。运用本方法对汞标准NISTSRM3133和UM-Almadn实验室内标样长达7个月的测定,结果表明,本方法外精度<0.06‰(2SD)。此外,对一系列环境样品的同位素组成进行了测定,样品的外精度<0.10‰(2SD)。测定样品δ202Hg变化范围为-3.48‰~0.63‰,幅度达4.11‰。 展开更多
关键词 同位素比值 多接受杯电感耦合等离子体质谱
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天坑释义 被引量:20
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作者 朱学稳 Tony WALTHAM +1 位作者 朱学稳(著译) 张远海(校) 《中国岩溶》 CAS CSCD 北大核心 2006年第B08期35-42,共8页
天坑是一种特大型塌陷漏斗,它的演化包括大型洞穴厅堂的洞顶崩塌和大型暗河对大量崩塌块石的搬运。天坑这个术语,首先在中国使用,随后成为世界性的喀斯特词汇。
关键词 喀斯特 漏斗 天坑 中国 释义
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意义疗法的理论、方法与技术:基于存在积极心理学的视角 被引量:18
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作者 张荣伟 连榕 +1 位作者 李丹 Pual TPWong 《心理学探新》 CSSCI 北大核心 2020年第3期195-202,共8页
意义疗法是以存在积极心理学为理论基础,以构建个体生命意义为目的,实现生活正负两极性的动态平衡,从而解决其心理困扰获得心理治愈与成长的一种整合性心理咨询与治疗方法。起源于Frankl意义学说的意义疗法是通往人类美好生活的路径,它... 意义疗法是以存在积极心理学为理论基础,以构建个体生命意义为目的,实现生活正负两极性的动态平衡,从而解决其心理困扰获得心理治愈与成长的一种整合性心理咨询与治疗方法。起源于Frankl意义学说的意义疗法是通往人类美好生活的路径,它源于对苦难生活所隐含意义的本质认识。在理论上,意义疗法以意义定向看世界为中心,以意义管理理论和双系统模型为支架;在方法上,为保障意义获得,应遵循8个基本问题和12条原则,充分发挥意义源的作用,实现意义获得的双路径统一;在技术上,灵活采用趋向性(PURE)策略、回避性(ABCDE)策略、以及双视角双通道策略或其它策略的整合。意义疗法因包含了精神成分而超越了心理动力学和个体心理学等传统心理治疗方式。未来研究还需明确意义疗法整合了哪些流派的具体方法和技术,细化意义疗法主要的技术与策略的操作步骤,考察成熟幸福感量表在中国文化下的适用性,以及充分整合质性与量化研究方法检验意义疗法在中国的适用性。 展开更多
关键词 意义疗法 存在积极心理学 美好生活 意义定向 双系统模型 成熟幸福感
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Internet addiction and problematic Internet use: A systematic review of clinical research 被引量:17
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作者 Daria J Kuss Olatz Lopez-Fernandez 《World Journal of Psychiatry》 SCIE 2016年第1期143-176,共34页
AIM: To provide a comprehensive overview of clinical studies on the clinical picture of Internet-use related addictions from a holistic perspective. A literature search was conducted using the database Web of Science.... AIM: To provide a comprehensive overview of clinical studies on the clinical picture of Internet-use related addictions from a holistic perspective. A literature search was conducted using the database Web of Science.METHODS: Over the last 15 years, the number of Internet users has increased by 1000%, and at the same time, research on addictive Internet use has proliferated. Internet addiction has not yet been understood very well, and research on its etiology and natural history is still in its infancy. In 2013, the American Psychiatric Association included Internet Gaming Disorder in the appendix of the updated version of the Diagnostic and Statistical Manual for Mental Disorders(DSM-5) as condition that requires further research prior to official inclusion in the main manual, with important repercussions for research and treatment. To date, reviews have focused on clinical and treatment studies of Internet addiction and Internet Gaming Disorder. This arguably limits the analysis to a specific diagnosis of a potential disorder that has not yet been officially recognised in the Western world, rather than a comprehensive and inclusive investigation of Internet-use related addictions(including problematic Internet use) more generally. RESULTS: The systematic literature review identified a total of 46 relevant studies. The included studies used clinical samples, and focused on characteristics of treatment seekers and online addiction treatment. Four main types of clinical research studies were identified, namely research involving(1) treatment seeker characteristics;(2) psychopharmacotherapy;(3) psychological therapy; and(4) combined treatment. CONCLUSION: A consensus regarding diagnostic criteria and measures is needed to improve reliability across studies and to develop effective and efficient treatment approaches for treatment seekers. 展开更多
关键词 INTERNET ADDICTION PROBLEMATIC INTERNET use Gaming ADDICTION INTERNET Gaming DISORDER Clinical studies TREATMENT seekers TREATMENT Therapy
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Enhanced light-matter interactions in dielectric nanostructures via machine-learning approach 被引量:14
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作者 Lei Xu Mohsen Rahmani +9 位作者 Yixuan Ma Daria ASmirnova Khosro Zangeneh Kamali Fu Deng Yan Kei Chiang Lujun Huang Haoyang Zhang Stephen Gould Dragomir N.Neshev Andrey E.Miroshnichenko 《Advanced Photonics》 EI CSCD 2020年第2期57-67,共11页
A key concept underlying the specific functionalities of metasurfaces is the use of constituent components to shape the wavefront of the light on demand.Metasurfaces are versatile,novel platforms for manipulating the ... A key concept underlying the specific functionalities of metasurfaces is the use of constituent components to shape the wavefront of the light on demand.Metasurfaces are versatile,novel platforms for manipulating the scattering,color,phase,or intensity of light.Currently,one of the typical approaches for designing a metasurface is to optimize one or two variables among a vast number of fixed parameters,such as various materials’properties and coupling effects,as well as the geometrical parameters.Ideally,this would require multidimensional space optimization through direct numerical simulations.Recently,an alternative,popular approach allows for reducing the computational cost significantly based on a deep-learning-assisted method.We utilize a deep-learning approach for obtaining high-quality factor(high-Q)resonances with desired characteristics,such as linewidth,amplitude,and spectral position.We exploit such high-Q resonances for enhancedlight–matter interaction in nonlinearoptical metasurfaces and optomechanical vibrations,simultaneously.We demonstrate that optimized metasurfaces achieve up to 400-fold enhancement of the third-harmonic generation;at the same time,they also contribute to 100-fold enhancement of the amplitude of optomechanical vibrations.This approach can be further used to realize structures with unconventional scattering responses. 展开更多
关键词 machine learning dielectric nanostructures Fano resonance third-harmonic generation optoacoustics
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Infrared upconversion imaging in nonlinear metasurfaces 被引量:12
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作者 Rocio Camacho-Morales Davide Rocco +15 位作者 Lei Xu Valerio Flavio Gili Nikolay Dimitrov Lyubomir Stoyanov Zhonghua Ma Andrei Komar Mykhaylo Lysevych Fouad Karouta Alexander Dreischuh Hark Hoe Tan Giuseppe Leo Costantino De Angelis Chennupati Jagadish Andrey E.Miroshnichenko Mohsen Rahmani Dragomir N.Neshev 《Advanced Photonics》 EI CSCD 2021年第3期83-92,共10页
Infrared imaging is a crucial technique in a multitude of applications,including night vision,autonomous vehicle navigation,optical tomography,and food quality control.Conventional infrared imaging technologies,howeve... Infrared imaging is a crucial technique in a multitude of applications,including night vision,autonomous vehicle navigation,optical tomography,and food quality control.Conventional infrared imaging technologies,however,require the use of materials such as narrow bandgap semiconductors,which are sensitive to thermal noise and often require cryogenic cooling.We demonstrate a compact all-optical alternative to perform infrared imaging in a metasurface composed of GaAs semiconductor nanoantennas,using a nonlinear wave-mixing process.We experimentally show the upconversion of short-wave infrared wavelengths via the coherent parametric process of sum-frequency generation.In this process,an infrared image of a target is mixed inside the metasurface with a strong pump beam,translating the image from the infrared to the visible in a nanoscale ultrathin imaging device.Our results open up new opportunities for the development of compact infrared imaging devices with applications in infrared vision and life sciences. 展开更多
关键词 metasurfaces nonlinear optical processes infrared photonics imaging.
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易逝品最优定价、订货量和广告投入的联合确定 被引量:11
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作者 熊中楷 彭志强 YU Xiong 《工业工程与管理》 北大核心 2009年第2期32-37,共6页
以需求受价格和广告投入影响的报童问题为研究对象,需求函数采用混合形式,研究了一类随机需求下易逝品最优定价、订货量和广告投入联合确定的报童问题。建立了需求受价格和广告投入影响的报童问题的数学模型,求解得出最优定价、广告投... 以需求受价格和广告投入影响的报童问题为研究对象,需求函数采用混合形式,研究了一类随机需求下易逝品最优定价、订货量和广告投入联合确定的报童问题。建立了需求受价格和广告投入影响的报童问题的数学模型,求解得出最优定价、广告投入和订货量。并与需求仅受价格影响的报童问题做了比较,最后给出算例说明了所得的结论。 展开更多
关键词 易逝品 报童模型 定价 广告投入
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“原位开窗”技术重建主动脉弓上分支血管的Meta分析 被引量:12
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作者 周楚 Tung On Yau 乔彤 《中国血管外科杂志(电子版)》 2018年第3期174-182,187,共10页
目的系统评价应用"原位开窗"技术治疗胸主动脉(夹层)动脉瘤重建主动脉弓上分支血管的安全性及有效性。方法收集截止2018年8月前发表的关于应用"原位开窗"技术腔内修复主动脉弓部病变(夹层/动脉瘤),同时保留弓上血... 目的系统评价应用"原位开窗"技术治疗胸主动脉(夹层)动脉瘤重建主动脉弓上分支血管的安全性及有效性。方法收集截止2018年8月前发表的关于应用"原位开窗"技术腔内修复主动脉弓部病变(夹层/动脉瘤),同时保留弓上血管血供的文献,回顾性分析技术成功率、内漏发生率、并发症发生率及病死率等近中期临床结果。结果共纳入11篇文献的262例胸主动脉(夹层)动脉瘤患者,技术成功率为94%,平均随访时间为16.85个月,共13例患者出现术后支架内漏(Ⅰ型内漏10例,Ⅱ型内漏3例),术后内漏总发生率为8%,30天病死率和随访期手术相关病死率分别为3.44%和0。结论应用"原位开窗"技术重建弓上分支血管技术成功率较高,并发症发生率及病死率较低。 展开更多
关键词 动脉瘤 夹层 支架 主动脉弓 腔内修复术 原位开窗
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The positive function of selenium supplementation on reducing nitrate accumulation in hydroponic lettuce(Lactuca sativa L.) 被引量:9
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作者 LEI Bo BIAN Zhong-hua +7 位作者 YANG Qi-chang WANG Jun CHENG Rui-feng LI Kun LIU Wen-ke ZHANG Yi FANG Hui TONG Yun-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第4期837-846,共10页
High nitrate(NO3-) in vegetables, especially in leaf vegetables poses threaten to human health. Selenium(Se) is an important element for maintaining human health, and exogenous Se application during vegetable and crop... High nitrate(NO3-) in vegetables, especially in leaf vegetables poses threaten to human health. Selenium(Se) is an important element for maintaining human health, and exogenous Se application during vegetable and crop production is an effective way to prevent Se deficiency in human bodies. Exogenous Se shows positive function on plant growth and nutrition uptake under abiotic and/or biotic stresses. However, the influence of exogenous Se on NO3-accumulation in hydroponic vegetables is still not clear. In the present study, hydroponic lettuce plants were subjected to six different concentrations(0, 0.1, 0.5, 5, 10 and 50 μmol L–1) of Se as Na2 Se O3. The effects of Se on NO3-content, plant growth, and photosynthetic capacity of lettuce(Lactuca sativa L.) were investigated. The results showed that exogenous Se positively decreased NO3-content and this effect was concentration-dependent. The lowest NO3-content was obtained under 0.5 μmol L–1 Se treatment. The application of Se enhanced photosynthetic capacity by increasing the photosynthesis rate(Pn), stomatal conductance(Cs) and the transpiration efficiency(Tr) of lettuce. The transportation and assimilation of NO3-and activities of nitrogen metabolism enzymes in lettuce were also analysed. The NO3-efflux in the lettuce roots was markedly increased, but the efflux of NO3-from the root to the shoot was decreased after treated with exogenous Se. Moreover, Se application stimulated NO3-assimilation by enhancing nitrate reductase(NR), nitrite reductase(Ni R), glutamine synthetase(GS) and glutamate synthase enzyme(GOGAT) activities. These results provide direct evidence that exogenous Se shows positive function on decreasing NO3-accumulation via regulating the transport and enhancing activities of nitrogen metabolism enzyme in lettuce. We suggested that 0.5 μmol L–1 Se can be used to reduce NO3-content and increase hydroponic lettuce yield. 展开更多
关键词 SELENIUM NO_3^- nitrogen metabolism enzyme SIET photosynthetic performance LETTUCE
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The role of phosphorus in the metabolism of arsenate by a freshwater green alga, Chlorella vulgaris 被引量:7
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作者 Josh Baker Dirk Wallschlager 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第11期169-178,共10页
A freshwater microalga, Chlorella vulgaris, was grown in the presence of varying phosphate concentrations(〈 10–500 μg/L P) and environmentally realistic concentrations of arsenate(As(Ⅴ))(5–50 μg/L As). A... A freshwater microalga, Chlorella vulgaris, was grown in the presence of varying phosphate concentrations(〈 10–500 μg/L P) and environmentally realistic concentrations of arsenate(As(Ⅴ))(5–50 μg/L As). Arsenic speciation in the culture medium and total cellular arsenic were measured using AEC-ICP-MS and ICP-DRC-MS, respectively, to determine arsenic biotransformation and uptake in the various phosphorus scenarios. At high phosphate concentration in the culture medium, 〉 100 μg/L P, the uptake and biotransformation of As(Ⅴ) was minimal and dimethylarsonate(DMAs(Ⅴ)) was the dominant metabolite excreted by C. vulgaris, albeit at relatively low concentrations. At common environmental P concentrations, 0–50 μg/L P, the uptake and biotransformation of As(Ⅴ) increased. At these higher As-uptake levels, arsenite(As(Ⅲ)) was the predominant metabolite excreted from the cell. The concentrations of As(Ⅲ) in these low P conditions were much higher than the concentrations of methylated arsenicals observed at the various P concentrations studied. The switchover threshold between the(small) methylation and(large) reduction of As(Ⅴ) occurred around a cellular As concentration of 1 fg/cell. The observed nearly quantitative conversion of As(Ⅴ) to As(Ⅲ) under low phosphate conditions indicates the importance of As(Ⅴ) bio-reduction at common freshwater P concentrations. These findings on the influence of phosphorus on arsenic uptake, accumulation and excretion are discussed in relation to previously published research. The impact that the two scenarios of As(Ⅴ) metabolism, As(Ⅲ) excretion at high As(Ⅴ)-uptake and methylarsenical excretion at low As(Ⅴ)-uptake, have on freshwater arsenic speciation is discussed. 展开更多
关键词 Arsenic Speciation Phosphorus Freshwater algae Toxicity Biotransformation
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Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial
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作者 Jason Philip Appleton Lisa J Woodhouse +19 位作者 Craig S Anderson Sandeep Ankolekar Lesley Cala Mark Dixon Timothy J England Kailash Krishnan Grant Mair Keith W Muir John Potter Christopher I Price Marc Randall Thompson G Robinson Christine Roffe Else C Sandset Jeffrey L Saver Angela Shone Aloysius Niroshan Siriwardena Joanna M Wardlaw Nikola Sprigg Philip M Bath 《Stroke & Vascular Neurology》 SCIE CSCD 2024年第1期38-49,I0035-I0046,共24页
Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is unclear.Here,we assess the safety and eff... Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is unclear.Here,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of onset.The primary outcome was a shift in scores on the modified Rankin scale(mRS)at day 90.Secondary outcomes included death;a global analysis(Wei-Lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’markers.Data were reported as n(%),mean(SD),median[IQR],adjusted common OR(acOR),mean difference or Mann-Whitney difference(MWD)with 95%CI.Results 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow Coma Scale 14(2)and time from onset to randomisation 67[45,108]min.Neuroimaging‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%CI 0.85 to 1.54),death or global analysis(MWD 0.00,95%CI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe stroke.Conclusions In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital trials.WHAT IS ALREADY KNOWN ON THIS TOPIC⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those with acute stroke treated within 6hou 展开更多
关键词 GLASGOW nitrate random
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Tendency to Avoid Physical Activity and Sport:Associations with Weight Stigma,and Psychological Distress in a Two-Wave Longitudinal Study
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作者 Saffari Mohsen Yi-Ching Lin +7 位作者 Po-Ching Huang Yu-Ting Huang Ru-Yi Huang Chi Hsien Huang Jung-Sheng Chen Wai Chuen Poon Mark D.Griffiths Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第8期633-641,共9页
Background:Physical inactivity is a major public health problem worldwide that results in physical and mental health problems.One major issue for physical inactivity is weight stigma(WS),especially perceived WS,which ... Background:Physical inactivity is a major public health problem worldwide that results in physical and mental health problems.One major issue for physical inactivity is weight stigma(WS),especially perceived WS,which could lead to a tendency to avoid physical activity(PA).To better understand the association between perceived WS and PA,knowledge of the likely mediators in this association such as weight bias internalization(WBI)and psychological distress were investigated in the present study.Methods:Using a two-wave longitudinal study and convenient sampling,388 Taiwan residents participants(55%females;mean age=29.7 years[SD±6.3])completed two surveys six months apart.Body mass index(BMI),Perceived Weight Stigma Scale(PWSS),Weight Bias Internalization Scale(WBIS),Depression,Anxiety,Stress Scale(DASS-21),and Tendency to Avoid Physical Activity and Sport Scale(TAPAS)were assessed.Results:A mediation model controlling for age,gender,and BMI with 5000 bootstrapping resamples was performed.Perceived WS exerted significant direct effects on WBI(β=0.25;p<0.001),psychological distress(β=0.15;p=0.003),and tendency to avoid PA(β=0.10;p=0.027);WBI exerted a significant direct effect on tendency to avoid PA(β=0.47;p<0.001).Standardized indirect effects of WBI and psychological distress on the association between perceived WS and tendency to avoid PA were 0.12 and 0.01,respectively.Conclusion:Given the direct association of perceived WS on the tendency to avoid PA and the mediating role of WBI in this association,interventions addressing perceived WS and WBI may contribute to promoting PA.Therefore,health interventionists(both when planning and executing PA programs)need to consider weight stigmawhen encouraging physical activity. 展开更多
关键词 Mediation model physical activity psychological distress weight stigma young adults
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Selenium distribution and nitrate metabolism in hydroponic lettuce(Lactuca sativa L.): Effects of selenium forms and light spectra 被引量:8
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作者 BIAN Zhong-hua LEI Bo +3 位作者 CHENG Rui-feng WANG Yu LI Tao YANG Qi-chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期133-144,共12页
A deficiency in selenium(Se) in the human diet is a worldwide problem. The intake of Se-rich vegetables can be a safe way to combat Se deficiency for humans. However, most leafy vegetables can accumulate a high conten... A deficiency in selenium(Se) in the human diet is a worldwide problem. The intake of Se-rich vegetables can be a safe way to combat Se deficiency for humans. However, most leafy vegetables can accumulate a high content of nitrates, which poses a potential threat to human health. Light is an important environmental factor that regulates the uptake and distribution of mineral elements and nitrogen metabolism in plants. However, the effects of Se forms and light conditions, especially light spectra, on the uptake and translocation of Se and on nitrate reduction are poorly understood. In this study, lettuce(Lactuca sativa L.) was treated with exogenous Se applied as selenate(10 mmol L^-1) and selenite(0.5 mmol L^-1) and grown under five different light spectra: fluorescent light(FL), monochromatic red LED light(R), monochromatic blue LED light(B), and mixed red and blue LED light with a red to blue light ratio at 4(R/B=4), 8(R/B=8), and 12(R/B=12), respectively. The effects of light spectra and Se forms on plant growth, photosynthetic performance, Se accumulation and nitrate reduction were investigated. The results showed that the light spectra and Se forms had significant interactions for plant growth, foliar Se accumulation and nitrate reduction. The Se concentration and nitrate content in the leaves were negatively correlated with the percentage of red light from the light sources. Compared to Se applied as selenite, exogenous Se applied as selenate was more effective in reducing nitrate via promoting nitrate reductase and glutamate synthase activities. The lowest nitrate content and highest plant biomass were observed under R/B=8 for both the selenate and selenite treatments. The significant effect of the light spectra on the root concentration factor and translocation factor of Se resulted in marked variations in the Se concentrations in the roots and leaves. Compared with FL, red and blue LED light led to significant decreases in the foliar Se concentration. The results from this study suggest that the light sp 展开更多
关键词 SELENIUM light spectra NITRATES nitrogen metabolism enzymes LEDs Lactuca sativa L.
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Is intraprocedural intravenous aspirin safe for patients who require emergent extracranial stenting during mechanical thrombectomy?
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作者 Adam Ingleton Marko Raseta +9 位作者 Rui-En Chung Kevin Jun Hui Kow Jake Weddell Sanjeev Nayak Changez Jadun Zafar Hashim Noman Qayyum Phillip Ferdinand Indira Natarajan Christine Roffe 《Stroke & Vascular Neurology》 SCIE CSCD 2024年第3期279-288,I0247,共11页
Background Intraoperative antiplatelet therapy is recommended for emergent stenting during mechanical thrombectomy(MT).Most patients undergoing MT are also given thrombolysis.Antiplatelet agents are contraindicated wi... Background Intraoperative antiplatelet therapy is recommended for emergent stenting during mechanical thrombectomy(MT).Most patients undergoing MT are also given thrombolysis.Antiplatelet agents are contraindicated within 24 hours of thrombolysis.We evaluated outcomes and complications of patients stented with and without intravenous aspirin during MT.Methods All patients who underwent emergent extracranial stenting during MT at the Royal Stoke University Hospital,UK between 2010 and 2020,were included.Patients were thrombolysed before MT,unless contraindicated.Aspirin 500 mg intravenously was given intraoperatively at the discretion of the operator.Symptomatic intracranial haemorrhage(sICH)and the National Institutes for Health Stroke Scale score(NIHSS)were recorded at 7 days,and mortality and functional recovery(modified Rankin Scale:mRS≤2)at 90 days.Results Out of 565 patients treated by MT 102 patients(median age 67 IQR 57–72 years,baseline median NIHSS 18 IQR 13–23,76(75%)thrombolysed)had a stent placed.Of these 49(48%)were given aspirin and 53(52%)were not.Patients treated with aspirin had greater NIHSS improvement(median 8 IQR 1–16 vs median 3 IQR-9–8 points,p=0.003),but there were no significant differences in sICH(2/49(4%)vs 9/53(17%)),mRS≤2(25/49(51%)vs 19/53(36%))and mortality(10/49(20%)vs 12/53(23%))with and without aspirin.NIHSS improvement(median 12 IQR 4–18 vs median 7 IQR-7–10,p=0.01)was greater,and mortality was lower(4/33(12%)vs 6/15(40%),p=0.05)when aspirin was combined with thrombolysis,than for aspirin alone,with no increase in bleeding.Conclusion Our findings based on registry data derived from routine clinical care suggest that intraprocedural intravenous aspirin in patients undergoing emergent stenting during MT does not increase sICH and is associated with good clinical outcomes,even when combined with intravenous thrombolysis. 展开更多
关键词 PATIENTS ASPIRIN INTRAVENOUS
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Topology-Optimized 4D Printing of a Soft Actuator 被引量:7
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作者 Ali Zolfagharian Martin Denk +2 位作者 Mahdi Bodaghi Abbas Z.Kouzani Akif Kaynak 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2020年第3期418-430,共13页
Soft robots and actuators are emerging devices providing more capabilities in the field of robotics.More flexibility and compliance attributing to soft functional materials used in the fabrication of these devices mak... Soft robots and actuators are emerging devices providing more capabilities in the field of robotics.More flexibility and compliance attributing to soft functional materials used in the fabrication of these devices make them ideal for delivering delicate tasks in fragile environments,such as food and biomedical sectors.Yet,the intuitive nonlinearity of soft functional materials and their anisotropic actuation in compliant mechanisms constitute an existent challenge in improving their performance.Topology optimization(TO)along with four-dimensional(4D)printing is a powerful digital tool that can be used to obtain optimal internal architectures for the efficient performance of porous soft actuators.This paper employs TO analysis for achieving high bending deflection of a 3D printed polyelectrolyte actuator,which shows bending deformations in response to electrical stimuli in an electrolyte solution.The performance of the actuator is studied in terms of maximum bending and actuation rate compared with a solid,uniformly 3D printed and topology-optimized actuator.The experimental results proved the effectiveness of TO on achieving higher bending deformation and actuation rate against a uniformly 3D printed actuator. 展开更多
关键词 Topology optimization 4D printing 3D printing Soft actuator
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale 被引量:1
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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ANALYSIS ON INFILTRATIVE CHARACTERISTICS OF DEFORMABLE POROUS MATAL RUBBER MATERIAL AND PARAMATERS IDENTIFICATION 被引量:7
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作者 Jiang Hongyuan Xia Yuhong +1 位作者 Su Daizhong Белоусов А И 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期562-565,共4页
The effect of deformation of porous material on infiltrative performance is investigated. Based on Darcy theory and Boit principle, the Reynolds equation and mathematical expression of deformable metal rubber (MR) m... The effect of deformation of porous material on infiltrative performance is investigated. Based on Darcy theory and Boit principle, the Reynolds equation and mathematical expression of deformable metal rubber (MR) material under laminar flow are obtained according to the change of porosity of metal rubber. It is shown that the throttle of MR material is dependent on its porosity and diameter of metal wires. It will be of great value for the application of MR in throttle field. 展开更多
关键词 Metal rubber Porous material Infiltrative coefficient Porosity Reynolds equation
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In vivo analysis of hybrid hydrogels containing dual growth factor combinations,and skeletal stem cells under mechanical stimulation for bone repair
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作者 David Gothard Michael Rotherham +13 位作者 Emma L.Smith Janos M.Kanczler James Henstock Julia A.Wells Carol A.Roberts Omar Qutachi Heather Peto Hassan Rashidi Luis Rojo Lisa J.White Molly M.Stevens Alicia J.El Haj Felicity R.J.ose Richard O.C.Oreffo 《Mechanobiology in Medicine》 2024年第4期97-109,共13页
Bone tissue engineering requires a combination of materials,cells,growth factors and mechanical cues to recapitulate bone formation.In this study we evaluated hybrid hydrogels for minimally invasive bone formation by ... Bone tissue engineering requires a combination of materials,cells,growth factors and mechanical cues to recapitulate bone formation.In this study we evaluated hybrid hydrogels for minimally invasive bone formation by combining biomaterials with skeletal stem cells and staged release of growth factors together with mechanotransduction.Hybrid hydrogels consisting of alginate and decellularized,demineralised bone extracellular matrix(ALG/ECM)were seeded with Stro-1t human bone marrow stromal cells(HBMSCs).Dual combinations of growth factors within staged-release polylactic-co-glycolic acid(PLGA)microparticles were added to hydrogels to mimic,in part,the signalling events in bone regeneration:VEGF,TGF-β_(3),PTHrP(fast release),or BMP-2,vitamin D_(3)(slow release).Mechanotransduction was initiated using magnetic fields to remotely actuate superparamagnetic nanoparticles(MNP)targeted to TREK1 ion channels.Hybrid hydrogels were implanted subcutaneously within mice for 28 days,and evaluated for bone formation using micro-CT and histology.Control hydrogels lacking HBMSCs,growth factors,or MNP became mineralised,and neither growth factors,HBMSCs,nor mechanotransduction increased bone formation.However,structural differences in the newly-formed bone were influenced by growth factors.Slow release of BMP-2 induced thick bone trabeculae and PTHrP or VitD_(3)increased bone formation.However,fast-release of TGF-β_(3)and VEGF resulted in thin trabeculae.Mechanotransduction reversed the trabecular thinning and increased collagen deposition with PTHrP and VitD_(3).Our findings demonstrate the potential of hybrid ALG/ECM hydrogel–cell–growth factor constructs to repair bone in combination with mechanotransduction for fine-tuning bone structure.This approach may form a minimally invasive reparative strategy for bone tissue engineering applications. 展开更多
关键词 Growth factors Controlled release Bone ECM Bone formation MECHANOTRANSDUCTION Skeletal stem cell
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A review on additive/subtractive hybrid manufacturing of directed energy deposition(DED)process 被引量:6
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作者 Mohammadreza Lalegani Dezaki Ahmad Serjouei +4 位作者 Ali Zolfagharian Mohammad Fotouhi Mahmoud Moradi M.K.A.Ariffin Mahdi Bodaghi 《Advanced Powder Materials》 2022年第4期39-58,共20页
Additive manufacturing(AM)processes are reliable techniques to build highly complex metallic parts.Direct energy deposition(DED)is one of the most common technologies to 3D print metal alloys.Despite a wide range of l... Additive manufacturing(AM)processes are reliable techniques to build highly complex metallic parts.Direct energy deposition(DED)is one of the most common technologies to 3D print metal alloys.Despite a wide range of literature that has discussed the ability of DED in metal printing,weak binding,poor accuracy,and rough surface still exist in final products.Thus,limitations in 3D printing of metal powder and wire indicate post-processing techniques required to achieve high quality in both mechanical properties and surface quality.Therefore,hybrid manufacturing(HM),specifically additive/subtractive hybrid manufacturing(ASHM)of DED has been proposed to enhance product quality.ASHM is a capable process that combines two technologies with 3-axis or multi-axis machines.Different methods have been suggested to increase the accuracy of machines to find better quality and microstructure.In contrast,drawbacks in ASHM still exist such as limitations in existing reliable materials and poor accuracy in machine coordination to avoid collision in the multi-axes machine.It should be noted that there is no review work with focuses on both DED and hybridization of DED processes.Thus,in this review work,a unique study of DED in comparison to ASHM as well as novel techniques are discussed with the objective of showing the capabilities of each process and the benefits of using them for different applications.Finally,new gaps are discussed in ASHM to enhance the layer bonding and surface quality with the processes'effects on microstructures and performance. 展开更多
关键词 Additive manufacturing Additive/subtractive hybrid manufacturing 3D printing Hybrid manufacturing Metal alloysDirect energy deposition MACHINING
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