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Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury 被引量:2
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作者 Mou Gao Qin Dong +4 位作者 Zhijun Yang Dan Zou Yajuan Han Zhanfeng Chen Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期872-880,共9页
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen... Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury. 展开更多
关键词 closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p NEUROGENESIS
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Factors Associated with Closely Spaced Pregnancies at the Departmental Hospital Centre of Zou-Collines (Benin) in 2022
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作者 Klikpezo Roger Hounkponou Nouéssewa Fanny Maryline +7 位作者 Atade Sèdjro Raoul Agbegbanou Eudoxie Ahouingnan Yeyinou Salifou Badaryatou Dettin Eric Obossou Achilles Imorou Sidi Salifou Kabibou 《Open Journal of Obstetrics and Gynecology》 2024年第1期89-101,共13页
Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organiza... Introduction: Birth spacing to prevent closely-spaced pregnancies, which are a source of maternal and neonatal morbidity and mortality, is not always respected by our women, as recommended by the World Health Organization (WHO). The objective was to study the factors associated with closely-spaced pregnancies among women followed at the Departmental Hospital Center du Zou et du Colline (DHC/Z-C) in 2022. Study Method: This was a descriptive, analytical cross-sectional study with prospective data collection from 20 May to 30 June 2022. Results: At the end of the study, 83 of the 117 women surveyed had close pregnancies, a frequency of 70.94%. They had an average age of 27.0 ± 6.3 years and were of Fon ethnicity and related in 91.57% of cases. The majority were married (96.60%). The factors significantly associated with these closely spaced pregnancies were age between 25 and 30 years, household occupation, age at first birth, age at marriage, women’s perception of contraceptive method (CM), women’s knowledge of the existence of a center providing family planning services and non-use of MC. Conclusion: Close pregnancies are still very common in the commune of Abomey. It is therefore important to increase the use of contraceptive methods in this part of the country. 展开更多
关键词 close Pregnancy Associated Factors DHC/Z-C
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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury
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作者 Mou Gao Qin Dong +3 位作者 Dan Zou Zhijun Yang Lili Guo Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1416-1430,共15页
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ... Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury. 展开更多
关键词 Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell MICROGLIA NEUROINFLAMMATION
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Formation of a Rapidly Rotating Classical Be-star in a Massive Close Binary System
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作者 Evgeny Staritsin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期44-50,共7页
This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by m... This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange. 展开更多
关键词 (stars:)binaries(including multiple):close stars:emission-line BE stars:early-type stars:rotation
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Sensing-Communication-Computing-Control Closed Loop for NOMA-UAV Systems
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作者 Lei Chengleyang Feng Wei +4 位作者 Wang Jue Wang Yanmin Jin Shi Yin Liuguo Ge Ning 《China Communications》 SCIE CSCD 2024年第8期89-103,共15页
In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communic... In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communication,and computing modules to support various requirements of robots.In the task process,different modules assist the robots to perform tasks in a closed-loop way,which is referred to as a sensing-communication-computing-control(SC3)loop.In this work,we investigate a UAV-aided system containing multiple SC^(3)loops,which leverages non-orthogonal multiple access(NOMA)for efficient resource sharing.We describe and compare three different modelling levels for the SC^(3)loop.Based on the entropy SC^(3)loop model,a sum linear quadratic regulator(LQR)control cost minimization problem is formulated by optimizing the communication power.Further for the assure-to-be-stable case,we show that the original problem can be approximated by a modified user fairness problem,and accordingly gain more insights into the optimal solutions.Simulation results demonstrate the performance gain of using NOMA in such task-oriented systems,as well as the superiority of our proposed closed-loop-oriented design. 展开更多
关键词 closed loop linear quadratic regulator(LQR) non-orthogonal multiple access(NOMA) power allocation unmanned aerial vehicle(UAV)
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Design and Test of Closed Hydraulic Transmission System of 4WD High-clearance Wheeled Sprayer
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作者 Hengfeng CHEN Xiaobo XU 《Plant Diseases and Pests》 2024年第3期14-20,共7页
In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic sys... In conjunction with the working characteristics of the high-clearance wheeled sprayer and the benefits of the closed hydraulic system,a series of reasonable working parameters should be established,and a hydraulic system that fulfills the requisite specifications should be designed.The AMESim software model is employed to construct a closed hydraulic transmission system,and the simulation analysis is then performed according to the data of hydraulic components.According to analysis results,the prototype can be optimized and upgraded,and a verification test is further carried out.The test results demonstrate that the designed closed hydraulic transmission system meets the actual working requirements of the high-clearance wheeled sprayer and provides a stable experimental platform for intelligent control of agricultural machinery. 展开更多
关键词 closed hydraulic transmission system High-clearance Wheeled sprayer Modeling and simulation Verification test
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Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft
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作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar close Observations and Proximity Experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system Advanced thermal management system
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Study on the Effect of Behavioral Interventions Based on the Theory of“Knowledge,Attitude,Practice”on Tuberculosis Cognitive Level of Close Contacts
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作者 Beiyan Zhang Yifei Hu +2 位作者 Jun Ji Donghui Hao Xuehui Jiao 《Journal of Clinical and Nursing Research》 2024年第2期123-128,共6页
Objective:Based on the theory of“Knowledge,Attitude,Practice,”health education was carried out for close contact with tuberculosis(TB)at a university in Beijing,and its impact on the students’awareness of TB was st... Objective:Based on the theory of“Knowledge,Attitude,Practice,”health education was carried out for close contact with tuberculosis(TB)at a university in Beijing,and its impact on the students’awareness of TB was studied.This study could provide a reference for effective health education interventions among close contacts of TB in undergraduates.Methods:102 undergraduates who had close contact with one confirmed case of pulmonary TB in April 2021 at a university were randomly divided into a control group and an intervention group.The intervention group was given the“Knowledge,Attitude,Practice”health education intervention by professionally trained doctors,and were asked to complete a self-designed TB-related questionnaire before and after the intervention.Both groups performed the Tuberculin Skin Test(TST)and chest X-ray(CR)examination.Results:The rate of the TST test was 18.6%,and CR examination showed 0 cases of pulmonary TB.The survey results showed that the TB awareness rate(96.1%,49/51)in the intervention group was significantly higher than that of the control group(51.0%,26/51),and the differences in awareness rate between the two groups were statistically significant(P<0.05).Regarding the attitude/skills toward TB,the prevalence rate of tuberculosis-related attitude/behavior in the intervention group(94.1%,47/51)was significantly higher than that of the control group(60.8%,31/51),and the differences between the two groups were statistically significant(P<0.05).Conclusion:Both self-controlled and parallel-controlled studies showed that the health education intervention of“Knowledge,Attitude,Practice”improved the awareness of TB among close contacts of TB in undergraduates. 展开更多
关键词 UNDERGRADUATES close contact of tuberculosis Behavioral intervention Health education
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Synthetical condition assessment of long span suspension bridge based on closeness degree and FAHP 被引量:1
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作者 郭彤 李爱群 +1 位作者 赵大亮 王浩 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期261-265,共5页
Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a math... Based on the theory of pattern recognition, the concept of closeness degree between fuzzy sets is brought into the condition assessment of long span bridges. Using the fuzzy analytic hierarchy process (FAHP), a mathematical model of a multi-objective assessment of a long span suspension bridge is set up. An example is given to show the procedure in the synthetical condition assessment of the Runyang Suspension Bridge, which includes the hierarchical division, the definition of factor weights and fuzzy membership functions, and the calculation of closeness degrees, etc. The assessment combines both the data from the health monitoring system and the manual tests. The classification of evaluation items as well as the calculation of deterministic and nondeterministic items is presented. Compared with the traditional method of point rating, this method can better describe the discreteness of monitoring data and the fuzziness in the condition assessment. 展开更多
关键词 pattern recognition fuzzy analytic hierarchy process closeness degree synthetical condition assessment suspension bridge
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基于敏感属性值语义桶分组的t-closeness隐私模型 被引量:14
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作者 张健沛 谢静 +1 位作者 杨静 张冰 《计算机研究与发展》 EI CSCD 北大核心 2014年第1期126-137,共12页
t-closeness模型是数据发布领域中用于抵御相似性攻击和偏斜攻击的一种有效方法,但其采用的EMD(earth mover's distance)距离没有考虑等价类与数据表间敏感属性分布的稳定性,不能全面地衡量分布间距离,在分布间稳定差异过大时会大... t-closeness模型是数据发布领域中用于抵御相似性攻击和偏斜攻击的一种有效方法,但其采用的EMD(earth mover's distance)距离没有考虑等价类与数据表间敏感属性分布的稳定性,不能全面地衡量分布间距离,在分布间稳定差异过大时会大大提高隐私泄露的风险.针对这种局限,提出了一种SABuk t-closeness模型,它在传统t-closeness模型的基础上,为更加准确地度量分布间距离,以EMD距离与KL散度(kullback-leibler divergence)结合构建距离度量标准.同时,根据敏感属性的层次树结构,对数据表进行语义相似性桶分组划分,然后采用贪心思想生成满足要求的最小等价类,并且运用k-近邻的思想来选取QI(quasi-identifiers)值相似的元组生成等价类.实验结果表明,SABuk t-closeness模型在牺牲少量时间的前提下减少了信息损失,能在有效地保护敏感信息不泄露的同时保持较高的数据效用. 展开更多
关键词 隐私保护 桶分组 t-closeness模型 EMD KL散度
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模糊t-closeness隐私保护方法研究 被引量:4
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作者 陈晓宇 韩斌 +1 位作者 黄树成 朱文正 《计算机应用与软件》 北大核心 2018年第9期317-322,333,共7页
针对t-closeness隐私保护方法中数据泛化机制带来的信息损失量较大的不足,基于模糊理论提出一种模糊t-closeness隐私保护方法。该方法给出数据模糊化的定义,设计并实现替代泛化机制的数据模糊化过程。该过程在模糊聚类的基础上划分出符... 针对t-closeness隐私保护方法中数据泛化机制带来的信息损失量较大的不足,基于模糊理论提出一种模糊t-closeness隐私保护方法。该方法给出数据模糊化的定义,设计并实现替代泛化机制的数据模糊化过程。该过程在模糊聚类的基础上划分出符合t-closeness隐私保护要求的模糊等价类,对元素隶属度限幅求取平均值以获取元素模糊化的替代值。同时针对元素中分类属性给出模糊化语义结构树的构造方法。进行理论证明并通过实验验证模糊t-closeness隐私保护方法降低信息损失量的同时,提高了数据的隐私保护强度。 展开更多
关键词 t—closeness 隐私保护 模糊理论 模糊化
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Evaluation Indexes of Degree of Closeness between Strategy and Project Portfolio Allocation
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作者 Libiao Bai Sijun Bai 《American Journal of Operations Research》 2015年第1期38-46,共9页
The main activities in project portfolio allocation management are selecting the right project components given a strategy. It is crucial to establish a scientific system of evaluation indexes to guarantee the closene... The main activities in project portfolio allocation management are selecting the right project components given a strategy. It is crucial to establish a scientific system of evaluation indexes to guarantee the closeness between strategy and project portfolio allocation optimally. With organizations growing in sizes, the functions and objectives of project components are becoming more and more different. It is necessary to set evaluation indexes of the degree of closeness from the perspectives of financial, market share, social effects, and so on according to the strategy-oriented process of project portfolio allocation. This paper proposes a project portfolio allocation process under strategic orientation and evaluation indexes of the degree of closeness between strategy and project portfolio allocation. This will help projects managers make portfolio allocation decisions. 展开更多
关键词 PROJECT PORTFOLIO ALLOCATION Evaluation Indexes DEGREE of closeness PPA Process
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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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Effect of periodic wide atmospheric pressure change on CO emission in closed goaf
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作者 Zhuangzhuang Shao Bo Tan +6 位作者 Ruili Hu Xiaozhen Song Yan Guo Tianze Li Shuhui Fu Chaohuan Chen Haiyan Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期139-150,共12页
Atmospheric pressure fuctuation is one of the most important factors afecting the climate environment and gas emission in the fre area.To obtain the infuence rule of the surface atmospheric pressure change on the gas ... Atmospheric pressure fuctuation is one of the most important factors afecting the climate environment and gas emission in the fre area.To obtain the infuence rule of the surface atmospheric pressure change on the gas sampling and abnormal emission in the mine closed goaf,the No.1 coal mine in Dananhu was taken as the research object.Using Fourier transform and Fisher harmonic analysis and other statistical methods,the infuence of the periodic variation of atmospheric pressure on the gas leakage and outfow in the closed goaf was studied.The results showed that there were three atmospheric pressure periods of 15.2 d,1 d and 182.2 d,and the probability was greater than 95%.The time period with the highest number of atmospheric pressure peaks was 7:00–8:00,which accounted for 20.2%of total occurrence number in a day.And the time periods with the highest number of atmospheric pressure trough were 2:00,15:00 and 16:00,accounting for 27.4%.The peak-to-trough transition time was mainly concentrated around 6 h,and the diurnal variation curve of atmospheric pressure was mainly bimodal.The atmospheric pressure change rate was mostly concentrated in 10–50 Pa/h.It was determined that the distance that the gas sampling pipe was pre-laid into the inner side of the closed wall should be greater than 44.4 m,and the CO concentration and atmospheric pressure in the closed goaf were both periodic and negative with atmospheric pressure.The research results have important guiding signifcance for the monitoring,early warning and environmental protection of the goaf. 展开更多
关键词 Atmospheric pressure Periodic variation closed goaf CO emission Coal mine
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Knowing one’s parents’ friends: association with parental closeness
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作者 何玲熹 《留学》 2019年第12期78-79,共2页
Is one knowing about their parents’social lives associated with how close they are to them?An obvious answer might be yes.We first found that in a sample of Chinese students,they are more aware of the number of frien... Is one knowing about their parents’social lives associated with how close they are to them?An obvious answer might be yes.We first found that in a sample of Chinese students,they are more aware of the number of friends their mother has tham the friends their dads have.We then found that,for girls,knowing their mom and dad's friends predicts closeness with dad.Closeness to mother is not associated with knowledge of either parents’social network.For boys,however,knowing mothers’friends(but not the father’s friends)predicts their closeness to the father.As with girls,knowing either parent’s network is not associated with maternal closeness.This research implies that there are different ways closeness emerges between mothers and fathers and their children. 展开更多
关键词 parents’social LIVES MATERNAL closeness children
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Performance analyses of two-phase closed thermosyphons for road embankments in the high-latitude permafrost regions
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作者 WANG Guan-fu LIN Chuang +3 位作者 ZHU Long FENG De-cheng XIN Yang-yang ZHANG Feng 《Journal of Mountain Science》 SCIE CSCD 2023年第11期3138-3153,共16页
Two-phase closed thermosyphons(TPCTs)are widely used in infrastructure constructions in permafrost regions.Due to different climatic conditions,the effectiveness of TPCT will also be different,especially in the extrem... Two-phase closed thermosyphons(TPCTs)are widely used in infrastructure constructions in permafrost regions.Due to different climatic conditions,the effectiveness of TPCT will also be different,especially in the extremely cold region of the Da Xing'anling Mountains.In this study,a series of three-dimensional finite element TPCT embankment models were established based on the ZhanglingMohe highway TPCT test section in Da Xing'anling Mountains,and the thermal characteristics and the cooling effect of the TPCTs were analyzed.The results indicated that the TPCTs installed in the northeastern high-latitude regions is effective in cooling and stabilizing the embankment.The working cycle of the TPCTs is nearly 7 months,and the cooling range of the TPCTs can reach 3 m in this region.However,due to the extremely low temperature,the TPCT generates a large radial gradient in the permafrost layer.Meanwhile,by changing the climate conditions,the same type of TPCT embankment located in the Da Xing'anling Mountains,the Xiao Xing'anling Mountains,and the Qinghai-Tibet Plateau permafrost regions were simulated.Based on the comparison of the climate differences between the Qinghai-Tibet Plateau and Northeast China,the differences in the effectiveness of TPCTs were studied.Finally,the limitations of using existing TPCTs in high-latitude permafrost regions of China were discussed and the potential improvements of the TPCT in cold regions were presented. 展开更多
关键词 PERMAFROST Highway embankment Two-phase closed thermosyphon Numerical simulation Climatic condition Cooling performance
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Children’s Health, Parent-Child Activities, Using Digital Devices, and Social Competence: Serial Mediation
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作者 Ching-Fen Lee Shain-May Tang 《Health》 2023年第8期883-894,共12页
Background: Studies have pointed out the influence of different children’s activities and prolonged use of digital products on their social development. However, whether the parent-child activities and using digital ... Background: Studies have pointed out the influence of different children’s activities and prolonged use of digital products on their social development. However, whether the parent-child activities and using digital devices were serial mediators of the relationship between children’s health and social development needs further verification. Purpose: This study explored how parent-child activities and children’s use of digital devices influence the relationship between children’s health and their social competence. Method: This study used data from Kids in Taiwan: National Longitudinal Study of Child Development and Care. A total sample of 2164 participants was used in this study. Serial mediation analyses were performed using model six of Hayes’ PROCESS (2012). Results: This study found that parent-child activities and the use of digital devices can serially mediate the relationship between children’s health and social competence. Children’s health could directly improve their social competence, but it could also serially mediate social competence by increasing parent-child activities and reducing the use of digital devices. Conclusion: Childcare policy planners and parenting educators should not only call on parents to reduce the use of electronic products for their children, but also encourage parents to spend more time interacting with their children, so that children can learn social skills by interacting with others in their daily lives. 展开更多
关键词 Children’s Health Social Competence parent-child Activities Using Digital Devices PRESCHOOLER
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Closed corner divertor with B×▽B away from the divertor:a promising divertor scenario for tokamak power exhaust
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作者 徐国盛 贾国章 +5 位作者 丁根凡 陶余强 孟令义 余林 王亮 刘建斌 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第10期60-67,共8页
A major challenge facing the steady-state operation of tokamak fusion reactors is to develop a viable divertor solution with order-of-magnitude increase in power handling capability as compared with present experience... A major challenge facing the steady-state operation of tokamak fusion reactors is to develop a viable divertor solution with order-of-magnitude increase in power handling capability as compared with present experience.A recently developed divertor concept for this end has been tested recently on EAST tokamak through combining the effects of a closed divertor corner and E×B drifts.The E×B drifts in the divertor move particles towards the outer divertor corner area in the scrape-off layer for B×▽B directed away from the divertor,which can significantly enhance the particle concentration there,facilitating divertor detachment.In recent EAST experiments,the effects have been demonstrated where the lowest electron temperature at the divertor plate is obtained with strike point located close to the corner in the horizontal target and with B×▽B away from the divertor.These experimental results are in reasonable agreement with SOLPS-ITER simulations including drift effects,suggesting that the new divertor concept potentially provides a promising divertor solution for long-pulse operations of future tokamak fusion reactors with much higher power fluxes. 展开更多
关键词 divertor concept closed divertor corner E×B drifts SOLPS-ITER simulation EAST tokamak
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Can Closeness Established Experimentally Impact Friendship Development and Homesickness?
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作者 Christopher Russo Robin Valeri 《Psychology Research》 2015年第6期347-354,共8页
关键词 实验 合作伙伴 参与者 封闭性 操作 随访
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Parameter Design of Current Double Closed Loop for T-Type Three-Level Grid-Connected Inverter
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作者 Tiankui Sun Mingming Shi +3 位作者 Xiaolong Xiao Ping He Yu Ji Zhiyuan Yuan 《Energy Engineering》 EI 2023年第7期1621-1636,共16页
To reduce current harmonics caused by switching frequency,T-type grid-connected inverter topology with LCL filter is adopted.In view of the disadvantages of the slow response speed of the traditional current control a... To reduce current harmonics caused by switching frequency,T-type grid-connected inverter topology with LCL filter is adopted.In view of the disadvantages of the slow response speed of the traditional current control and the failure to eliminate the influence of the LCL filter on the grid-connected current by using current PI control alone,a current double closed loop PI current tracking control is proposed.Through the theoretical analysis of the grid-connected inverter control principle,the grid-connected inverter control model is designed,and the transfer functionmodel of each control link is deduced,and the current loop PI regulator is designed at last.The simulation results show that the control strategy is feasible. 展开更多
关键词 T-type inverter active damping current double closed loop
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