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坚持社会层面的思考 深耕建筑实践——访日本M.A.O.一级建筑士事务所首席设计师、总经理 毛厚德先生
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作者 毛厚德 《设计家》 2013年第5期46-49,共4页
1988年留学东京工业大学,期间师从于建筑大师坂本一成。1992年获得东京都立大学建筑意匠学硕士。1999年加入了(株)日本设计(师从于日本建筑大师小林克弘),并担任首席设计师。2000年创建M.A.O.一级建筑士事务所,曾主持设计了... 1988年留学东京工业大学,期间师从于建筑大师坂本一成。1992年获得东京都立大学建筑意匠学硕士。1999年加入了(株)日本设计(师从于日本建筑大师小林克弘),并担任首席设计师。2000年创建M.A.O.一级建筑士事务所,曾主持设计了日本长崎一荷兰村,东京迪斯尼海,东京品川新干线大厦等作品。 展开更多
关键词 首席设计师 建筑实践 事务所 日本 总经理 东京工业大学 深耕 层面
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基于最大瓦解结构的科学研究前沿关键节点识别与演化路径分析
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作者 白如江 刘琦 +4 位作者 石文秀 王天一 张新雨 牛湘荷 刘睿琳 《现代情报》 北大核心 2026年第1期52-64,共13页
[目的/意义]通过最大瓦解结构准确识别科学研究前沿中的关键节点并追踪其演化路径,为把握领域发展规律、优化科研资源配置提供支持,突破现有研究聚焦孤立节点的局部特征,以及难以捕捉知识网络中具有协同作用且对全局连通性有级联破坏力... [目的/意义]通过最大瓦解结构准确识别科学研究前沿中的关键节点并追踪其演化路径,为把握领域发展规律、优化科研资源配置提供支持,突破现有研究聚焦孤立节点的局部特征,以及难以捕捉知识网络中具有协同作用且对全局连通性有级联破坏力的关键节点集合的问题。[方法/过程]以量子通信领域为例,基于2015—2024年Web of Science的6538篇文献构建关键词共现网络,融合多中心性指标并利用熵权法评估节点重要性,采用贪心算法识别MDS,分析其功能协同特征与演化轨迹。[结果/结论]研究表明,MDS仅占网络规模的18%~22%,移除该集合后网络最大连通组件规模下降超过70%,效果显著优于传统方法。关键节点在功能上呈现“主题—方法—工具—目标”的互补协同结构,其演化路径清晰展示了量子通信从理论奠基、技术攻坚到应用落地的三阶段发展轨迹,验证了MDS框架的有效性和实用性。 展开更多
关键词 科学研究前沿 关键节点识别 最大瓦解结构 网络瓦解 演化路径
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Hippocampal damage through foreign body placement in organotypic cultures leads to plastic responses in newly born granule cells
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作者 Tassilo Jungenitz Lukas Frey +2 位作者 Sophia Kirscht Stephan W.Schwarzacher Angélica Zepeda 《Neural Regeneration Research》 2026年第3期1142-1150,共9页
The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves gl... The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves global alterations,making understanding plastic responses triggered by local damage difficult.One key feature of the dentate gyrus is that it contains a well-defined neurogenic niche,the subgranular zone,and beyond neurogenesis,newly born granule cells may maintain a“young”phenotype throughout life,adding to the plastic nature of the structure.Here,we present a novel experimental model of local brain damage in organotypic entorhino-hippocampal cultures that results in the activation of adjacent newly born granule cells.A small piece of filter paper was placed on the surface of the granule cell layer of the dentate gyrus,which evoked a foreign body reaction of astrocytes,along with the activation of local young neurons expressing doublecortin.Forty-eight hours after foreign body placement,the number of doublecortin-immunoreactive cells increased in the subgranular zone in the direct vicinity of the foreign body,whereas overall increased doublecortin immunoreactivity was observed in the granule cell layer and molecular layer of the dentate gyrus.Foreign body placement in the pyramidal layer of the CA1 region evoked a comparable local astroglial reaction but did not lead to an increase in doublecortin-immunoreactive in either the CA1 region or the adjacent dentate gyrus.Seven days after foreign body placement in the dentate gyrus,the increase in doublecortin-immunoreactivity was no longer observed,indicating the transient activation of young cells.However,7 days after foreign body placement,the number of doublecortin-immunoreactive granule cells coimmunoreactive for calbindin was lower than that under the control conditions.As calbindin is a marker for mature granule cells,this result suggests that activated young cells remain at a more immature stage following foreign body placement.Live imaging of retrovirally green fluorescent protein-labeled newly born granule cells revealed the orientation and growth of their dendrites toward the foreign body placement.This novel experimental model of foreign body placement in organotypic entorhino-hippocampal cultures could serve as a valuable tool for studying both glial reactivity and neuronal plasticity,specifically of newly born neurons under controlled in vitro conditions. 展开更多
关键词 ASTROCYTE brain plasticity dendritic plasticity dentate gyrus focal brain injury hippocampus NEUROPLASTICITY NEUROREPAIR newborn granule cells regeneration REORGANIZATION
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Pericyte-glial cell interactions: Insights into brain health and disease
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作者 Ali Sepehrinezhad Ali Gorji 《Neural Regeneration Research》 2026年第4期1253-1263,共11页
Pericytes are multi-functional mural cells of the central nervous system that cover the capillary endothelial cells. Pericytes play a vital role in nervous system development, significantly influencing the formation, ... Pericytes are multi-functional mural cells of the central nervous system that cover the capillary endothelial cells. Pericytes play a vital role in nervous system development, significantly influencing the formation, maturation, and maintenance of the central nervous system. An expanding body of studies has revealed that pericytes establish carefully regulated interactions with oligodendrocytes, microglia, and astrocytes. These communications govern numerous critical brain processes, including angiogenesis, neurovascular unit homeostasis, blood–brain barrier integrity, cerebral blood flow regulation, and immune response initiation. Glial cells and pericytes participate in dynamic and reciprocal interactions, with each influencing and adjusting the functionality of the other. Pericytes have the ability to control astrocyte polarization, trigger differentiation of oligodendrocyte precursor cells, and initiate immunological responses in microglia. Various neurological disorders that compromise the integrity of the blood–brain barrier can disrupt these communications, impair waste clearance, and hinder cerebral blood circulation, contributing to neuroinflammation. In the context of neurodegeneration, these disruptions exacerbate pathological processes, such as neuronal damage, synaptic dysfunction, and impaired tissue repair. This article explores the complex interactions between pericytes and various glial cells in both healthy and pathological states of the central nervous system. It highlights their essential roles in neurovascular function and disease progression, providing important insights that may enhance our understanding of the molecular mechanisms underlying these interactions and guide potential therapeutic strategies for neurodegenerative disorders in future research. 展开更多
关键词 BRAIN INFLAMMATION NEUROPROTECTION neurovascular function therapeutic targets
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Incidence,risk factors and survival outcomes of post-transplant tertiary hyperparathyroidism in kidney recipients
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作者 Shmuel Hanson Jorge Menendez Lorenzo +3 位作者 Chukwuma Austin Chukwu Anirudh Rao Rachel Middleton Philip A Kalra 《World Journal of Transplantation》 2026年第1期153-166,共14页
BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite imp... BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite improved renal function.It is potentially associated with an increased risk of cardiovascular events,renal osteodystrophy,pathologic fractures,graft loss,and mortality.AIM To evaluate the incidence,risk factors,and outcomes of PT-tHPT amongst kidney transplant recipients.METHODS A total of 887 transplant recipients who underwent transplantation between 2000 and 2020 were evaluated.Univariable and multivariable logistic regression was performed to determine the predictors of tertiary hyperparathyroidism.Graft and recipient outcomes were assessed using multivariable Cox regression.A separate multivariable Cox regression was performed to determine the effect of treatment strategies on outcomes.RESULTS PT-tHPT,defined as elevated PTH(>65 ng/L)and persistent hypercalcemia(>2.60 mmol/L),was diagnosed in 14%of recipients.Risk factors for PT-tHPT included older age[odds ratio(OR)=1.36,P<0.001],Asian ethnicity(OR=0.33,P=0.006),total ischemia time(OR=1.03,P=0.048 per hour),pre-transplant serum calcium(OR=1.38,P<0.001)per decile increase,pre-transplant PTH level(OR=1.31,P<0.001)per decile increase,longer dialysis duration(OR=1.12,P=0.002)per year,history of acute rejection(OR=2.37,P=0.012),and slope of estimated glomerular filtration rate change(OR=0.91,P=0.001).There were a 3.4-fold higher risk of death-censored graft loss and a 1.9-fold greater risk of recipient death with PT-tHPT.The three treatment strategies of conservative management,calcimimetic and parathyroidectomy did not significantly change the graft or patient outcome.CONCLUSION Pretransplant elevated calcium and PTH levels,older age and dialysis duration are associated with PT-tHPT.While PT-tHPT significantly affects graft and recipient survival,the treatment strategies did not affect survival. 展开更多
关键词 Post-transplant tertiary hyperparathyroidism Kidney transplantation Parathyroid hormone PARATHYROIDECTOMY Calcimimetics Graft survival Risk factors Mineral bone disorder Fibroblast growth factor 23 Treatment outcomes
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Outcomes of basiliximab vs alemtuzumab induction in kidney allograft recipients with matched immunological Profiles:A retrospective cohort study
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作者 Chukwuma A Chukwu Philip A Kalra +3 位作者 Marcus Lowe Kay Poulton Titus Augustine Anirudh Rao 《World Journal of Transplantation》 2026年第1期182-192,共11页
BACKGROUND The use of induction immunosuppression agents has improved kidney transplant outcomes,but selecting the optimal agent remains a point of debate.AIM To compare the long-term outcomes of kidney transplant rec... BACKGROUND The use of induction immunosuppression agents has improved kidney transplant outcomes,but selecting the optimal agent remains a point of debate.AIM To compare the long-term outcomes of kidney transplant recipients receiving alemtuzumab vs basiliximab induction,focusing on graft function,acute rejection,infection,malignancy,post-transplant glomerulonephritis,and survival,using a propensity score matched cohort design.METHODS Kidney transplant recipients who received alemtuzumab or basiliximab induction from 2014 to 2019 across two nephrology centres in Northwest England were evaluated.Propensity score matching at a 1:1.5 ratio ensured comparability between cohorts.Baseline characteristics,immunosuppression regimens,and outcomes were analyzed.Linear,binary logistic and Cox proportional hazard regression models.RESULTS A total of 436 recipients were included,with a median follow-up of 5.2 years.The matched cohort(n=262)had a mean age of 51.1±13.5 years;39%were female and 92%were white.There was no significant difference in the cumulative incidence of acute rejection[odds ratio(OR)=2.10;95%CI:0.9-4.9;P=0.110].Compared with basiliximab,alemtuzumab was associated with lower estimated glomerular filtration rate at 12 months(-6.6 mL/minute/1.73 m2;95%CI:-10.5 to-2.7;P<0.001)and higher risks of cytomegalovirus viremia(OR=3.2;95%CI:1.6-6.5;P<0.001),BK viremia(OR=2.4;95%CI:1.1-5.5;P=0.02),post-transplant malignancy(OR=6.2;95%CI:1.6-29.9;P=0.013),and death-censored graft loss(hazard ratio=3.6;95%CI:1.2-11.4;P=0.03).No significant differences were observed in post-transplant glomerulonephritis or recipient mortality.CONCLUSION In this propensity score-matched analysis,alemtuzumab induction was associated with lower graft function at 12 months and higher risks of viral infection,post-transplant malignancy,and graft loss compared with basiliximab.These findings highlight the need for further studies to confirm the long-term safety and effectiveness of alemtuzumab in kidney transplantation. 展开更多
关键词 Kidney transplantation Immunosuppression induction ALEMTUZUMAB BASILIXIMAB Graft outcomes
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A method improving historical accuracy regarding notable figures focused on the biography of Emily Stowe
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作者 Carol Nash 《History and Philosophy of Medicine》 2026年第1期1-21,共21页
Background:A significant challenge regarding notable historical figures is determining the accuracy of the words and actions attributed to them with the limited available evidence,when their biographers have presented... Background:A significant challenge regarding notable historical figures is determining the accuracy of the words and actions attributed to them with the limited available evidence,when their biographers have presented a biased life assessment.Lauded as a founding suffragette,the first female school principal,and the first white female practicing physician in Canada,Dr.Emily Stowe did not help historians.She destroyed her records,leaving her life story to be told by her daughter,who portrayed her as a heroine–a view that has persisted since the start of the 20th century.To improve the accuracy of assessing the life of Emily Stowe,as much information as possible about Stowe must be collected and interpreted.Methods:Presented is a narrative research method for analyzing historical figures that examines 22 life-changing events in the life of Stowe by answering six types of questions about each event:when,where,who,what,how,and why.Results:This narrative research,representing a psychoanalytic research process,finds that much of the repeated story of Stowe is either exaggerated or likely false.Conclusion:Following the example of Emily Stowe,this unique method is applicable for improving the historical accuracy in assessing the lives of other notable figures.It represents a method extendable to those currently alive,outside the public eye,searching to develop their own narrative. 展开更多
关键词 historical figures Emily Stowe suffragettes female physicians Canada narrative research psychoanalytic research
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Pathophysiology of sildenafil-induced ocular toxicity in rats and treatment
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作者 Ibrahim Cicek Busra Caliskan +5 位作者 Bulent Yavuzer Durdu Altuner Tugba Bal Tastan Taha Abdulkadir Coban Ezgi Karatas Halis Suleyman 《International Journal of Ophthalmology(English edition)》 2026年第1期25-33,共9页
AIM:To examine the ocular toxicity linked to sildenafilusage and the possible protective benefits of adenosinetriphosphate(ATP)against this toxicity in rats.METHODS:Twenty-four male albino Wistar-type ratswere divided... AIM:To examine the ocular toxicity linked to sildenafilusage and the possible protective benefits of adenosinetriphosphate(ATP)against this toxicity in rats.METHODS:Twenty-four male albino Wistar-type ratswere divided into four equal groups(n=6/group)as follows:healthy group(HG),ATP-only group(ATPG),sildenafil-onlygroup(SILG),and ATP+sildenafil group(ATP+SLD).ATPG andATP+SLD groups were injected intraperitoneally with ATP(4 mg/kg),while SILG and HG groups were injected withsaline(0.9%NaCl)by the same route as a solvent.One hourafter the administration of ATP and solvent,sildenafil(10 m g/k g)was administered orally to the SILG andATP+SLD groups.This procedure was repeated once a dayfor 4wk.The animals were then sacrificed,eyeballs wereremoved and oxidant and antioxidant parameters weremeasured biochemically.Additionally,the ocular tissueswere evaluated histopathologically.RESULTS:Sildenafil increased oxidant(malondialdehyde)levels and decreased antioxidant levels(total glutathione,superoxide dismutase,catalase)in rat ocular tissues andcaused severe oxidative stress.In addition,sildenafil hasbeen shown histopathologically to cause oxidative damagein retinal layers.ATP treatment suppressed oxidative stressand attenuated histopathological damage in the retinal layers.CONCLUSION:ATP protects retinal tissue againstsildenafil-induced ocular oxidative damage in rats andmay contribute to the development of novel approaches toprevent or treat this damage. 展开更多
关键词 adenosine triphosphate ocular toxicity oxidative stress RATS RETINA SILDENAFIL
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Noninvasive On-Skin Biosensors for Monitoring Diabetes Mellitus
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作者 Ali Sedighi Tianyu Kou +1 位作者 Hui Huang Yi Li 《Nano-Micro Letters》 2026年第1期375-437,共63页
Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-in... Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-interfaced biosensors capable of analyzing sweat and skin biomarkers,providing innovative solutions for diabetes diagnosis and monitoring.This review comprehensively discusses the current developments in noninvasive wearable biosensors,emphasizing simultaneous detection of biochemical biomarkers(such as glucose,cortisol,lactate,branched-chain amino acids,and cytokines)and physiological signals(including heart rate,blood pressure,and sweat rate)for accurate,personalized diabetes management.We explore innovations in multimodal sensor design,materials science,biorecognition elements,and integration techniques,highlighting the importance of advanced data analytics,artificial intelligence-driven predictive algorithms,and closed-loop therapeutic systems.Additionally,the review addresses ongoing challenges in biomarker validation,sensor stability,user compliance,data privacy,and regulatory considerations.A holistic,multimodal approach enabled by these next-generation wearable biosensors holds significant potential for improving patient outcomes and facilitating proactive healthcare interventions in diabetes management. 展开更多
关键词 Wearable biosensors Multimodal sensors Diabetes monitoring Sweat biomarkers Glucose biosensors
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Harnessing CD146-positive mesenchymal stromal cells for precision therapy in acute respiratory distress syndrome
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作者 Özlem Tomsuk 《World Journal of Stem Cells》 2026年第1期1-7,共7页
Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal ce... Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal cells(MSCs)exhibited greater therapeutic efficacy than CD146-MSCs.These cells enhance epithelial repair through nuclear factor kappa B/cyclooxygenase-2-associated paracrine signaling and secretion of pro-angiogenic factors.We concur that MSCs hold significant promise for ARDS treatment;however,the heterogeneity of cell products is a translational barrier.Phenotype-aware strategies,such as CD146 enrichment,standardized potency assays,and extracellular vesicle profiling,are essential for improving the consistency of these studies.Further-more,advanced preclinical models,such as lung-on-a-chip systems,may provide more predictive insights into the therapeutic mechanisms.This article underscores the importance of CD146+MSCs in ARDS,emphasizes the need for precision in defining cell products,and discusses how integrating subset selection into translational pipelines could enhance the clinical impact of MSC-based therapies. 展开更多
关键词 Acute respiratory distress syndrome Mesenchymal stromal cells CD146 Nuclear factor kappa B/cyclooxygenase-2 signaling pathway Extracellular vesicles Endothelial barrier repair Precision medicine
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A bacterial type-II toxin-antitoxin-mediated gene amplification system in Saccharomyces cerevisiae
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作者 Samuel Evans Zeyu Lu +12 位作者 Liam McDonnell Will Anderson Francisco Peralta Tyson Watkins Hafna Ahmed Carlos Horacio Luna-Flores Thomas Loan Laura Navone Matt Trau Colin Scott Robert E*Speight Claudia E*Vickers Bingyin Peng 《Life Research》 2026年第1期5-16,共12页
Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we develop... Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we developed a bacterial type-II toxin-antitoxin-mediated method to manipulate genomic integration of tandem gene repeats in Saccharomyces cerevisiae and further visualised the evolutionary trajectories of gene repeats.We designed a tri-vector system to introduce toxin-antitoxin-driven gene amplification modules.Results:This system delivered multi-copy gene integration in the form of tandem gene repeats spontaneously and independently from toxin-antitoxin-mediated selection.Inducing the toxin(RelE)expressing via a copper(II)-inducible CUP1 promoter successfully drove the in-situ gene amplification of the antitoxin(RelB)module,resulting in~40 copies of a green fluorescence reporter gene per copy of genome.Copy-number changes,copy-number increase and copy-number decrease,and stable maintenance were visualised using the green fluorescence protein and blue chromoprotein AeBlue as reporters.Copy-number increases happened spontaneously and independent on a selection pressure.Increased copy number was quickly enriched through toxin-antitoxin-mediated selection.Conclusion:In summary,the bacterial toxin-antitoxin systems provide a flexible mechanism to manipulate gene copy number in eukaryotic cells and can be exploited for synthetic biology and metabolic engineering applications. 展开更多
关键词 tandem repeats gene amplification TOXIN-ANTITOXIN genetic dosage genome evolution
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Corrigendum to“Nitrosamines crisis in pharmaceuticals-Insights on toxicological implications,root causes and risk assessment:A systematic review”[J.Pharm.Anal.14(2024)100919] 被引量:2
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作者 Hemanth P.R.Vikram Tegginamath Pramod Kumar +9 位作者 Gunjan Kumar Narasimha M.Beeraka Rajashree Deka Sheik Mohammed Suhail Sandeep Jat Namitha Bannimath Gayatiri Padmanabhan Ravandur S.Chandan Pramod Kumar Bannimath Gurupadayya 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期934-936,共3页
Original statement in the Section 2:2.Literature search Our primary screening of 180 articles yielded the relevant data for this study.2.1.Study selection A total of 180 articles spanning from 1960 to the present day,... Original statement in the Section 2:2.Literature search Our primary screening of 180 articles yielded the relevant data for this study.2.1.Study selection A total of 180 articles spanning from 1960 to the present day,including original research,reviews,case reports and studies reporting nitrosamine impurities above the no-observed-adverse-effect levels(NOAEL)established by regulatory agencies,were initially screened.During the primary screening,we considered factors such as relevance,publication date,access to the full article text,and content. 展开更多
关键词 STATEMENT initially SPANNING
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科技领军企业新兴技术创新生态主导力的案例研究 被引量:1
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作者 何建洪 粟媛 +1 位作者 李林 高平 《管理评论》 北大核心 2025年第8期276-288,共13页
科技领军企业获取并维持新兴技术创新生态主导力是培育“链主”企业,增强创新链产业链自主性的重要措施。但这一目标经常面临环境动态变迁、企业资源错配、战略选择偏差等的挑战。本文基于“条件—行动—结果”分析思路,以宁德时代为案... 科技领军企业获取并维持新兴技术创新生态主导力是培育“链主”企业,增强创新链产业链自主性的重要措施。但这一目标经常面临环境动态变迁、企业资源错配、战略选择偏差等的挑战。本文基于“条件—行动—结果”分析思路,以宁德时代为案例分析对象,将其获取与维持新兴技术创新生态主导力的过程分为“乘风而起”与“久久为功”两个阶段,探究宁德时代如何通过战略思维指引下的资源编排行为来获取和维持创新生态主导力,并构建科技领军企业获取和维持新兴技术创新生态主导力的过程模型。研究发现:第一,外部产业环境与技术环境的耦合为企业基于不同创新生态主导力发展阶段而形成战略前瞻和战略共生的思维引领打开了机会窗口;第二,基于不同发展阶段现有资源差异而实施不同资源编排方式,是企业提高资源编排效率、锁定与放大既有优势,从而获取和维持创新生态主导力的关键。研究结论对于科技领军企业在复杂多变环境中获取并维持新兴技术创新生态主导力,进而强化科技领军企业培育与成长提供了有益启示。 展开更多
关键词 科技领军企业 创新生态主导力 战略前瞻 战略共生 资源编排
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不同电流下Ce掺杂AgCuO触头材料转移行为研究 被引量:2
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作者 王海涛 王彦岭 +3 位作者 李书舸 王景芹 李文华 赵伟 《电工技术学报》 北大核心 2025年第2期574-586,共13页
材料转移是电弧侵蚀中的一个必然过程,研究材料转移机制对于优化电极的材料选择和设计,开发更耐用、更稳定的电极材料有重要意义,该文以Ce掺杂的AgCuO触头为研究对象,分析材料转移方向在不同电流下变化的机理。通过溶胶-凝胶法和粉末冶... 材料转移是电弧侵蚀中的一个必然过程,研究材料转移机制对于优化电极的材料选择和设计,开发更耐用、更稳定的电极材料有重要意义,该文以Ce掺杂的AgCuO触头为研究对象,分析材料转移方向在不同电流下变化的机理。通过溶胶-凝胶法和粉末冶金法制备触头试样,借助JF04D电接触测试系统,在18 V电压下设置10、15、20和25 A四个电流等级,对触头进行20000次电弧侵蚀实验。首先对比了15 A电流条件下添加Ce后材料的性能提升情况,然后重点关注AgCuOCeO_(2)触头在不同电流下的燃弧能量与燃弧时间,测定侵蚀实验后阴阳极的质量变化,采用三维表面轮廓仪和扫描电镜表征阳极和阴极的表面侵蚀形貌,并对不同电流下的材料转移机制进行深入讨论分析。结果表明,Ce元素提升了触头性能,电流大小影响电极间金属离子和气体离子的浓度,引发金属相或气体相电弧的产生,导致材料转移方向在电流增大时发生改变。为选用和开发性能优良的AgCuO触头材料,进而提升AgCuO触头可靠性提供了理论依据。 展开更多
关键词 AgCuO触头材料 电弧侵蚀 材料转移 表面形貌 燃弧能量 燃弧时间
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数字治理与基本公共服务均衡性感知:机制分析与实证检验 被引量:6
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作者 王欣亮 邢誉丹 《西北大学学报(哲学社会科学版)》 北大核心 2025年第1期106-116,共11页
以解决基本公共服务供给失衡为目标,从政府治理数字化转型入手,使用多期CSS微观样本数据,进行估计、并对比分析基本公共服务供给感知效应,得出:①当且仅当数字治理能力跨越一定门槛时,才能提升公共服务供给均衡感知,在数字治理能力较弱... 以解决基本公共服务供给失衡为目标,从政府治理数字化转型入手,使用多期CSS微观样本数据,进行估计、并对比分析基本公共服务供给感知效应,得出:①当且仅当数字治理能力跨越一定门槛时,才能提升公共服务供给均衡感知,在数字治理能力较弱时,公共服务供给均衡感知不升反降;②数字治理能力与公共服务供给均衡感知间的“V”型关系源于公众参与的渠道效应,较弱的数字治理能力会挤出公众参与,从而阻滞均衡感知水平提升;③随着政府治理数字化向纵深转型,扩大数字服务事项覆盖度成为提升公共服务供给均衡感知的重要手段,但完善政务数字平台等基础设施的作用逐渐减弱;④数字鸿沟仍是数字治理感知均衡价值显现的约束条件,数字素养较低的老龄与低学历群体均衡感知提升困难;⑤“因地制宜”加速政府数字治理转型仍是解决公共服务“供给失衡”的关键,依托数字经济发展、提振地区经济发展基础并改善制度环境,能够增强数字治理的基本公共服务均衡感知效应。 展开更多
关键词 数字中国 精准治理 公共服务均衡性 数字协同治理 公共服务可及性
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人工智能驱动管理决策:应用、感知与偏见 被引量:6
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作者 谷炜 刘亚金 +1 位作者 Lu Feng Susan 闫相斌 《中国管理科学》 北大核心 2025年第5期99-112,共14页
近年来,由人工智能引领的新一轮科技创新和产业变革,突破了传统管理决策系统受限于数据可获取性和模型可解性的局限性,使得自动化的数据分析和智能化的决策支持成为可能。同时,在数字经济浪潮的推动下,人工智能技术已广泛渗透到企业运... 近年来,由人工智能引领的新一轮科技创新和产业变革,突破了传统管理决策系统受限于数据可获取性和模型可解性的局限性,使得自动化的数据分析和智能化的决策支持成为可能。同时,在数字经济浪潮的推动下,人工智能技术已广泛渗透到企业运营决策的各个环节,这为实现数字化管理创造了新的机遇,同时也给管理决策研究带来了新的挑战。本文从人工智能在不同商业环境的应用、人们对人工智能的感知和人工智能算法的偏见这三个方面对人工智能驱动的管理决策进行梳理、归纳和展望,并提出了未来研究的趋势和方向,为开展更深层次的研究提供了思路,为企业管理者和政策制定者进行科学决策提供参考,推动人工智能驱动管理决策的理论研究与商业实践。 展开更多
关键词 人工智能 管理与决策 机器学习 人机交互
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经济政策不确定性感知、数字化转型与企业研发投入——基于协同视角 被引量:1
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作者 刘伟 欧阳向霞 +2 位作者 王田俣 陈婧媛 齐昊 《技术经济》 北大核心 2025年第8期80-95,共16页
以科技创新推动产业创新,关键在于加大企业研发投入。在经济政策不确定性加剧和数字化转型深化的双重背景下,企业研发投入将受到何种影响具有重要研究价值。以2012—2022年沪深A股上市公司为研究对象,详细探讨了经济政策不确定性感知与... 以科技创新推动产业创新,关键在于加大企业研发投入。在经济政策不确定性加剧和数字化转型深化的双重背景下,企业研发投入将受到何种影响具有重要研究价值。以2012—2022年沪深A股上市公司为研究对象,详细探讨了经济政策不确定性感知与数字化转型对企业的研发投入的协同影响。研究结果表明,企业经济政策不确定性感知与数字化转型之间存在协同效应,这种协同效应显著加大了企业的研发投入力度。这一结论在采用工具变量法在内的等多种稳健性检验之后依然成立。异质性分析表明,企业经济政策不确定性感知与数字化转型两者对其研发投入的正向协同作用在第一、二产业,制造业企业及非国有企业中更为明显。机制研究显示,数字化人力资本、企业税收优惠和高管战略眼光是经济政策不确定性感知与数字化转型对企业研发投入发挥协同作用的三个潜在渠道。研究拓展了对于经济政策不确定性感知、数字化转型与企业研发投入三者关系的理论认识,并为企业在面对复杂多变的经济政策环境及加速数字化转型进程时,进行有效的研发决策提供了政策启示。 展开更多
关键词 经济政策不确定性感知 数字化转型 研发投入 协同效应
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基于三方演化博弈的充电桩规范运营治理研究 被引量:1
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作者 李晓敏 毛守恒 王安琪 《长江师范学院学报》 2025年第1期110-124,共15页
以充电桩为代表的充电基础设施是新型基础设施建设的重要内容,充电桩的规范运营关系到新能源汽车产业链的安全和韧性。针对充电桩市场上的违规运营问题,构建动态奖惩机制下充电桩运营商、地方政府和新能源汽车消费者三方参与的博弈模型... 以充电桩为代表的充电基础设施是新型基础设施建设的重要内容,充电桩的规范运营关系到新能源汽车产业链的安全和韧性。针对充电桩市场上的违规运营问题,构建动态奖惩机制下充电桩运营商、地方政府和新能源汽车消费者三方参与的博弈模型,对模型中可能存在的策略均衡点进行稳定性分析,并且利用数值仿真模拟主要参数变化对系统演化的影响。研究结果表明:第一,净收益的提高有利于激发充电桩运营商规范运营的积极性。第二,加大地方政府对充电桩运营商的奖励和惩罚力度均可以促进充电桩的规范运营,地方政府可以通过提高奖惩上限和扩大奖惩比例两种手段加大对充电桩运营商的奖惩力度。第三,地方政府实施奖惩结合政策的效果优于单独实施奖励性政策或惩罚性政策的效果,更为重要的是,在动态奖惩机制下,地方政府对充电桩运营商的奖惩力度存在临界值。当奖惩力度小于临界值时,惩罚性政策的激励效果优于奖励性政策;当奖惩力度大于临界值时,奖励性政策的激励效果优于惩罚性政策。第四,加大违规运营商对新能源汽车消费者的赔偿力度和降低消费者的投诉难度不仅能倒逼充电桩运营商规范运营,而且能引导消费者参与充电桩的规范运营治理。 展开更多
关键词 充电桩运营 治理策略 三方演化博弈 仿真
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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连续送风式长管呼吸器及应用
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作者 欧泽兵 周小平 《中国个体防护装备》 2025年第3期4-8,共5页
长管呼吸器也称为长管供气式呼吸器,长管呼吸器是呼气防护装备的一个重要类别。长管呼吸器使佩戴者的呼吸器官与环境空气隔绝,并通过导气管引入可呼吸气体,长管呼吸器分为自吸式长管呼吸器、连续供气式长管呼吸器和按需供气式长管呼吸器... 长管呼吸器也称为长管供气式呼吸器,长管呼吸器是呼气防护装备的一个重要类别。长管呼吸器使佩戴者的呼吸器官与环境空气隔绝,并通过导气管引入可呼吸气体,长管呼吸器分为自吸式长管呼吸器、连续供气式长管呼吸器和按需供气式长管呼吸器3种类型。长管呼吸器可以提供作业人员较高水平的防护。本文重点介绍连续供气式长管呼吸器的结构和特点,及连续供气式长管呼吸器的应用。 展开更多
关键词 长管呼吸器 连续供气式长管呼吸器 职业危害 风险评估 个体防护装备
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