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粉被虫草液体静置发酵产N^(6)-(2-羟乙基)腺苷培养基优化 被引量:1
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作者 廖兴刚 孟泽彬 +1 位作者 贺凤姣 文庭池 《分子植物育种》 北大核心 2025年第9期3046-3051,共6页
为了获得粉被虫草中高产N^(6)-(2-羟乙基)腺苷(HEA)的培养基,采用液体静置发酵的方式,以菌丝体HEA的产量为指标,HPLC法检测含量,采用单因素试验法研究培养基中8种碳源、8种氮源和8种无机盐对粉被虫草产HEA的影响;用正交试验筛选最佳培... 为了获得粉被虫草中高产N^(6)-(2-羟乙基)腺苷(HEA)的培养基,采用液体静置发酵的方式,以菌丝体HEA的产量为指标,HPLC法检测含量,采用单因素试验法研究培养基中8种碳源、8种氮源和8种无机盐对粉被虫草产HEA的影响;用正交试验筛选最佳培养基组合。结果显示,蛋白胨、果糖和ZnSO4分别是粉被虫草产HEA的最适氮源、最适碳源和最适无机盐;其最佳培养基组合为蛋白胨15 g/L、果糖40 g/L、硫酸锌0.5 g/L,此时的HEA产量为(92.311±2.209)mg/L,是目前报道粉被虫草中的最高产量。本研究将为粉被虫草规模生产HEA提供试验参考。 展开更多
关键词 粉被虫草 N^(6)-(2-羟乙基)腺苷 液体静置发酵 培养基
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具有n^(+)埋层和L型场板的Si/SiC异质结沟槽LDMOS器件 被引量:1
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作者 康怡 刘东 +2 位作者 卢山 鲁啸龙 胡夏融 《半导体技术》 北大核心 2025年第2期134-140,共7页
Si/4H-SiC异质结构能够同时结合Si材料的成熟工艺和SiC材料的宽禁带特性,在功率器件设计中具有巨大潜力。提出了一种具有n+埋层和L型场板的Si/SiC异质结沟槽横向双扩散金属氧化物半导体(LDMOS)器件。位于Si/SiC异质结界面SiC侧的重掺杂n... Si/4H-SiC异质结构能够同时结合Si材料的成熟工艺和SiC材料的宽禁带特性,在功率器件设计中具有巨大潜力。提出了一种具有n+埋层和L型场板的Si/SiC异质结沟槽横向双扩散金属氧化物半导体(LDMOS)器件。位于Si/SiC异质结界面SiC侧的重掺杂n+埋层能够有效降低界面势垒宽度,增强电子隧穿效应,降低界面电阻,进一步降低比导通电阻。位于厚氧化层角落并与漏极相连的L型场板通过在SiC漂移区和厚氧化层之间产生高电场,重塑器件横向和纵向电场强度分布,将击穿点从表面转移至体内,提高击穿电压。仿真结果表明,与传统SiC LDMOS器件相比,该器件的品质因数从109.29 MW/cm^(2)提升至159.92 MW/cm^(2),提高了46.36%,进一步改善了LDMOS器件导通电阻和击穿电压之间的折中关系,器件性能得到优化。 展开更多
关键词 横向双扩散金属氧化物半导体(LDMOS) Si/4H-SiC异质结 n^(+)埋层 L型场板 功率品质因数
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N^(6)-甲基腺苷修饰在调控肝药物代谢个体差异中的研究进展
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作者 程昊天 李勤浩 +1 位作者 李明珠 王沛 《中国药理学与毒理学杂志》 北大核心 2025年第5期361-369,共9页
肝药物代谢酶表达及活性具有显著的个体差异,可导致临床药物疗效减弱或不良反应的发生,对临床精准用药造成重大挑战。目前,核受体介导的转录调控及表观遗传机制,如组蛋白修饰、非编码RNA及DNA甲基化,为解释药物代谢酶的个体差异提供了... 肝药物代谢酶表达及活性具有显著的个体差异,可导致临床药物疗效减弱或不良反应的发生,对临床精准用药造成重大挑战。目前,核受体介导的转录调控及表观遗传机制,如组蛋白修饰、非编码RNA及DNA甲基化,为解释药物代谢酶的个体差异提供了重要线索,但仍有诸多问题尚待阐明。近年来,表观转录组学的发展为理解基因表达调控提供了新见解,其中N^(6)-甲基腺苷(m^(6)A)修饰是真核生物中最丰富的RNA修饰,参与多种生理病理过程。本文从m^(6)A修饰参与肝药物代谢酶的基础表达调控、m^(6)A修饰与核受体交互调控肝药物代谢酶在个体发育过程中的表达及异源物质暴露影响m^(6)A修饰水平改变肝药物代谢3个方面,综述m^(6)A修饰调控肝药物代谢的个体差异研究进展,以期为解释临床药物代谢个体差异提供新的理论依据。 展开更多
关键词 N^(6)-甲基腺苷修饰 RNA修饰 药物代谢酶 个体差异
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弹性设计理念下的复合型书店“1+N^(+)”体验设计路径探究
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作者 李媛蕊 任彝 武文婷 《建筑与文化》 2025年第2期41-43,共3页
在体验经济的推动下,实体书店的场所功能与空间意义经历着不断解构与重构的过程,逐步由单一的书籍销售场所向综合的文化体验场所转型,俨然成为城市文化的聚集地、传播中心及公共社交场所。此类复合型书店如何在快速发展的当下应对各种... 在体验经济的推动下,实体书店的场所功能与空间意义经历着不断解构与重构的过程,逐步由单一的书籍销售场所向综合的文化体验场所转型,俨然成为城市文化的聚集地、传播中心及公共社交场所。此类复合型书店如何在快速发展的当下应对各种变化和挑战,并在既定的空间和复合的消费体验需求之间取得平衡,是亟待解决的重要议题。文章结合当下复合型书店用户群体与体验需求分析,基于弹性设计理念,从空间、时间、社会生活三个层面提炼出复合型书店“1+N^(+)”体验设计路径及策略,以期为其转型升级提供理论支持和实践指导,助力体验经济时代下复合型书店模式的可持续发展。 展开更多
关键词 复合型书店 弹性设计 体验设计 1+N^(+) 设计路径
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Structural design in re duce d graphene oxide(RGO)metacomposites for enhanced microwave absorption in wide temperature spectrum 被引量:4
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作者 Haoxu Si Yi Zhang +5 位作者 Yuhao Liu Zhiyang Jiang Cuiping Li Jingwei Zhang Xiaoxiao Huang Chunhong Gong 《Journal of Materials Science & Technology》 2025年第3期211-220,共10页
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa... High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum. 展开更多
关键词 Microwave absorbing materials Metacomposites Equivalent electromagnetic parameters Structural parameters Wide temperature spectrum
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Multi-Band Integrated Networking for Efficient Spectrum Utilization in 6G 被引量:1
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作者 Wang Ailing Kong Lei +4 位作者 Liu Jianjun Xia Liang Wang Xiaoqian Wang Qixing Liu Guangyi 《China Communications》 2025年第4期42-54,共13页
The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic c... The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic complementarity of multiple bands are crucial for enhancing the spectrum efficiency,reducing network energy consumption,and ensuring a consistent user experience.This paper investigates the present researches and challenges associated with deployment of multi-band integrated networks in existing infrastructures.Then,an evolutionary path for integrated networking is proposed with the consideration of maturity of emerging technologies and practical network deployment.The proposed design principles for 6G multi-band integrated networking aim to achieve on-demand networking objectives,while the architecture supports full spectrum access and collaboration between high and low frequencies.In addition,the potential key air interface technologies and intelligent technologies for integrated networking are comprehensively discussed.It will be a crucial basis for the subsequent standards promotion of 6G multi-band integrated networking technology. 展开更多
关键词 full spectrum access high and low frequency collaboration multi-band integrated networking 6G spectrum efficiency
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N^(6)-甲基腺苷RNA修饰相关调节因子在肝细胞癌中的研究进展
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作者 伍杨 李甜 +4 位作者 朱玲玲 张润兵 吴楚江 杨妹霞 张久聪 《沈阳药科大学学报》 2025年第3期207-212,共6页
肝细胞癌(hepatocellular carcinoma,HCC)是全球癌症导致死亡的第四大原因,并已成为全球增长率最快的癌症之一。然而,尽管当前治疗领域的快速发展对HCC患者预后具有一定改善,但针对晚期HCC患者仍缺乏有效的治疗方法,其5年生存率仍较低,... 肝细胞癌(hepatocellular carcinoma,HCC)是全球癌症导致死亡的第四大原因,并已成为全球增长率最快的癌症之一。然而,尽管当前治疗领域的快速发展对HCC患者预后具有一定改善,但针对晚期HCC患者仍缺乏有效的治疗方法,其5年生存率仍较低,因此探究新的治疗手段势在必行。N^(6)-甲基腺苷(N^(6)-methyladenosine,m6A)修饰是真核生物中最常见、最丰富的内部RNA修饰之一,在调节RNA代谢中起着至关重要的作用。有研究发现,m6A相关调节因子可能与HCC的发生、发展密切相关。本文通过总结m6A相关调节因子在HCC发生中的调控作用和机制,以期为临床HCC诊断和治疗提供理论依据。 展开更多
关键词 N^(6)-甲基腺苷 RNA修饰 调节因子 肝细胞癌
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Exploring core symptoms and symptom clusters among patients with neuromyelitis optica spectrum disorder: A network analysis 被引量:1
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作者 Hao Liang Jiehan Chen +4 位作者 Lixin Wang Zhuyun Liu Haoyou Xu Min Zhao Xiaopei Zhang 《International Journal of Nursing Sciences》 2025年第2期152-160,共9页
Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to p... Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to participate in this online questionnaire survey.The survey tools included a general information questionnaire and a self-made NMOSD symptoms scale,which included the prevalence,severity,and distress of 29 symptoms.Cluster analysis was used to identify symptom clusters,and network analysis was used to analyze the symptom network and node characteristics and central indicators including strength centrality(r_(s)),closeness centrality(r_(c))and betweeness centrality(r_(b))were used to identify core symptoms and symptom clusters.Results The most common symptom was pain(65.7%),followed by paraesthesia(65.0%),fatigue(65.0%),easy awakening(63.6%).Regarding the burden level of symptoms,pain was the most burdensome symptom,followed by paraesthesia,easy awakening,fatigue,and difficulty falling asleep.Six clusters were identified:somatosensory,motor,visual,and memory symptom clusters,bladder and rectum symptom clusters,sleep symptoms clusters,and neuropsychological symptom clusters.Fatigue(r_(s)=12.39,r_(b)=68.00,r_(c)=0.02)was the most central and prominent bridge symptom,and motor symptom cluster(r_(s)=2.68,r_(c)=0.10)was the most central symptom cluster among the six clusters.Conclusions Our study demonstrated the necessity of symptom management targeting fatigue,pain,and motor symptom cluster in patients with NMOSD. 展开更多
关键词 Neuromyelitis optica spectrum disorder Network analysis SYMPTOM Symptom clusters NURSING
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N^(6)-甲基腺嘌呤甲基化修饰在头颈部鳞癌中的研究进展
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作者 赵学辉 朱静 《齐齐哈尔医学院学报》 2025年第20期1981-1986,共6页
N^(6)-甲基腺嘌呤(N^(6)-methyladenosine,m^(6)A)是发生在腺嘌呤第6位氮原子的甲基化,是核糖核酸(ribonucleic acid,RNA)中最为普遍、丰富和保守的内转录修饰。越来越多的研究表明,m^(6)A可以调控基因的表达,从而调节细胞的自我更新、... N^(6)-甲基腺嘌呤(N^(6)-methyladenosine,m^(6)A)是发生在腺嘌呤第6位氮原子的甲基化,是核糖核酸(ribonucleic acid,RNA)中最为普遍、丰富和保守的内转录修饰。越来越多的研究表明,m^(6)A可以调控基因的表达,从而调节细胞的自我更新、分化、侵袭和凋亡等过程。m^(6)A是由甲基转移酶合成组装、去甲基化酶可逆性去除并被读取蛋白结合行使生物学功能。本文介绍了m^(6)A在人类头颈部鳞癌中发病、进展的潜在机制及关键作用,在头颈部鳞癌的m^(6)A修饰中,有些具有致癌作用,而有些则抑制了肿瘤。文章总结综述了m^(6)A甲基化修饰在头颈部鳞癌中的最新研究进展并展望了m^(6)A RNA甲基化修饰在头颈部鳞癌治疗中的潜在前景。 展开更多
关键词 N^(6)-甲基腺嘌呤 甲基化 头颈部鳞癌 研究进展
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Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis
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作者 Li Xu Huiming Xu Changyong Tang 《Neural Regeneration Research》 SCIE CAS 2025年第2期354-365,共12页
Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism rem... Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction.To date,no effective treatment exists as the exact causative mechanism remains unknown.Therefore,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets.Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes.These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders.In this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model choices.In addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials. 展开更多
关键词 AQUAPORIN-4 experimental model neuromyelitis optica spectrum disorder PATHOGENESIS
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脂肪量和肥胖相关蛋白介导的N^(6)-腺苷酸甲基化在动脉粥样硬化中的研究进展 被引量:1
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作者 谢卓熠 陈宋涛 +4 位作者 孙璇 羊佩娟 陈雅丽 桂庆军 左建宏 《中国动脉硬化杂志》 2025年第3期257-263,共7页
N^(6)-腺苷酸甲基化是真核生物中最普遍的mRNA修饰,脂肪量和肥胖相关蛋白是其去甲基化酶,可有效去除mRNA的N^(6)-腺苷酸甲基化修饰,与肥胖密切相关。动脉粥样硬化是一种脂质驱动的血管壁慢性炎症性病变。研究发现脂肪量和肥胖相关蛋白... N^(6)-腺苷酸甲基化是真核生物中最普遍的mRNA修饰,脂肪量和肥胖相关蛋白是其去甲基化酶,可有效去除mRNA的N^(6)-腺苷酸甲基化修饰,与肥胖密切相关。动脉粥样硬化是一种脂质驱动的血管壁慢性炎症性病变。研究发现脂肪量和肥胖相关蛋白介导的N^(6)-腺苷酸甲基化可能通过脂代谢、氧化应激、线粒体功能障碍以及巨噬细胞泡沫化影响动脉粥样硬化的进程。 展开更多
关键词 脂肪量和肥胖相关蛋白 N^(6)-腺苷酸甲基化 动脉粥样硬化
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The Impairment Attention Capture by Topological Change in Children With Autism Spectrum Disorder
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作者 XU Hui-Lin XI Huan-Jun +4 位作者 DUAN Tao LI Jing LI Dan-Dan WANG Kai ZHU Chun-Yan 《生物化学与生物物理进展》 北大核心 2025年第1期223-232,共10页
Objective Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by difficulties with communication and social interaction,restricted and repetitive behaviors.Previous studies have indicated that... Objective Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by difficulties with communication and social interaction,restricted and repetitive behaviors.Previous studies have indicated that individuals with ASD exhibit early and lifelong attention deficits,which are closely related to the core symptoms of ASD.Basic visual attention processes may provide a critical foundation for their social communication and interaction abilities.Therefore,this study explores the behavior of children with ASD in capturing attention to changes in topological properties.Methods Our study recruited twenty-seven ASD children diagnosed by professional clinicians according to DSM-5 and twenty-eight typically developing(TD)age-matched controls.In an attention capture task,we recorded the saccadic behaviors of children with ASD and TD in response to topological change(TC)and non-topological change(nTC)stimuli.Saccadic reaction time(SRT),visual search time(VS),and first fixation dwell time(FFDT)were used as indicators of attentional bias.Pearson correlation tests between the clinical assessment scales and attentional bias were conducted.Results This study found that TD children had significantly faster SRT(P<0.05)and VS(P<0.05)for the TC stimuli compared to the nTC stimuli,while the children with ASD did not exhibit significant differences in either measure(P>0.05).Additionally,ASD children demonstrated significantly less attention towards the TC targets(measured by FFDT),in comparison to TD children(P<0.05).Furthermore,ASD children exhibited a significant negative linear correlation between their attentional bias(measured by VS)and their scores on the compulsive subscale(P<0.05).Conclusion The results suggest that children with ASD have difficulty shifting their attention to objects with topological changes during change detection.This atypical attention may affect the child’s cognitive and behavioral development,thereby impacting their social communication and interaction.In sum,our findings indicate that difficulties in attentional capture by TC may be a key feature of ASD. 展开更多
关键词 ATTENTION autism spectrum disorder perceptual object topological perception
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Management of critical care emergencies in children with autism spectrum disorder 被引量:1
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作者 Mohammed Al-Beltagi Nermin Kamal Saeed +2 位作者 Adel Salah Bediwy Rawan Alhawamdeh Reem Elbeltagi 《World Journal of Critical Care Medicine》 2025年第2期131-157,共27页
BACKGROUND Managing critical care emergencies in children with autism spectrum disorder(ASD)presents unique challenges due to their distinct sensory sensitivities,communication difficulties,and behavioral issues.Effec... BACKGROUND Managing critical care emergencies in children with autism spectrum disorder(ASD)presents unique challenges due to their distinct sensory sensitivities,communication difficulties,and behavioral issues.Effective strategies and protocols are essential for optimal care in these high-stress situations.AIM To systematically evaluate and synthesize current evidence on best practices for managing critical care emergencies in children with ASD.The review focuses on key areas,including sensory-friendly environments,communication strategies,behavioral management,and the role of multidisciplinary approaches.METHODS A comprehensive search was conducted across major medical databases,including PubMed,Embase,and Cochrane Library,for studies published between 2000 and 2023.Studies were selected based on their relevance to critical care management in children with ASD,encompassing randomized controlled trials,observational studies,qualitative research,and case studies.Data were extracted and analyzed to identify common themes,successful strategies,and areas for improvement.RESULTS The review identified 50 studies that met the inclusion criteria.Findings highlighted the importance of creating sensory-friendly environments,utilizing effective communication strategies,and implementing individualized behavioral management plans.These findings,derived from a comprehensive review of current evidence,provide valuable insights into the best practices for managing critical care emergencies in children with ASD.Sensory modifications,such as reduced lighting and noise,visual aids,and augmentative and alternative communication tools,enhanced patient comfort and cooperation.The involvement of multidisciplinary teams was crucial in delivering holistic care.Case studies provided practical insights and underscored the need for continuous refi-nement of protocols.CONCLUSION The review emphasizes the need for a tailored approach to managing critical care emergencies for children with ASD.Sensory-friendly adjustments,effective communication,and behavioral strategies supported by a mul-tidisciplinary team are integral to improving outcomes.Despite progress,ongoing refinement of care practices and protocols is necessary.This ongoing process addresses remaining challenges and engages healthcare professionals in continuous improvement of care for children with ASD in critical settings. 展开更多
关键词 Autism spectrum disorder Critical care emergencies Sensory sensitivities Behavioral management Communication strategies Multidisciplinary approach Pediatric intensive care Emergency protocols
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N^(6)-methyladenosine modification and skin diseases
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作者 JIANG Ling HU Yibo CHEN Jing 《中南大学学报(医学版)》 北大核心 2025年第3期382-395,共14页
Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of... Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of Science for literature related to m^(6)A and dermatological conditions.Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m^(6)A-related research.Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases,particularly melanoma,psoriasis,and skin development.Transcriptomic data from the Gene Expression Omnibus(GEO)were analyzed,revealing differential expression of m^(6)A-related genes in 4 types of skin tumors(including squamous cell carcinoma and basal cell carcinoma)as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis,and potential mechanisms of action were also explored.Findings suggest that m^(6)A modifications exhibit heterogeneity between neoplastic and nonneoplastic skin diseases.However,the regulatory mechanisms of m^(6)A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation. 展开更多
关键词 skin tumors inflammatory and immune-related skin diseases N^(6)-methyladenosine EPIGENETICS drug development
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Resource Optimization in Elastic Optical Networks Using Threshold-Based Routing and Fragmentation-Aware Spectrum Allocation
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作者 Kamagaté Beman Hamidja Kanga Koffi +2 位作者 Coulibaly Kpinan Tiekoura Konaté Adama Michel Babri 《Open Journal of Applied Sciences》 2025年第1期168-186,共19页
This paper proposes an efficient strategy for resource utilization in Elastic Optical Networks (EONs) to minimize spectrum fragmentation and reduce connection blocking probability during Routing and Spectrum Allocatio... This paper proposes an efficient strategy for resource utilization in Elastic Optical Networks (EONs) to minimize spectrum fragmentation and reduce connection blocking probability during Routing and Spectrum Allocation (RSA). The proposed method, Dynamic Threshold-Based Routing and Spectrum Allocation with Fragmentation Awareness (DT-RSAF), integrates rerouting and spectrum defragmentation as needed. By leveraging Yen’s shortest path algorithm, DT-RSAF enhances resource utilization while ensuring improved service continuity. A dynamic threshold mechanism enables the algorithm to adapt to varying network conditions, while its fragmentation awareness effectively mitigates spectrum fragmentation. Simulation results on NSFNET and COST 239 topologies demonstrate that DT-RSAF significantly outperforms methods such as K-Shortest Path Routing and Spectrum Allocation (KSP-RSA), Load Balanced and Fragmentation-Aware (LBFA), and the Invasive Weed Optimization-based RSA (IWO-RSA). Under heavy traffic, DT-RSAF reduces the blocking probability by up to 15% and achieves lower Bandwidth Fragmentation Ratios (BFR), ranging from 74% to 75%, compared to 77% - 80% for KSP-RSA, 75% - 77% for LBFA, and approximately 76% for IWO-RSA. DT-RSAF also demonstrated reasonable computation times compared to KSP-RSA, LBFA, and IWO-RSA. On a small-sized network, its computation time was 8710 times faster than that of Integer Linear Programming (ILP) on the same network topology. Additionally, it achieved a similar execution time to LBFA and outperformed IWO-RSA in terms of efficiency. These results highlight DT-RSAF’s capability to maintain large contiguous frequency blocks, making it highly effective for accommodating high-bandwidth requests in EONs while maintaining reasonable execution times. 展开更多
关键词 Elastic Optical Networks (EONs) spectrum Fragmentation Routing and spectrum Allocation (RSA) Connection Rerouting HEURISTIC
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RNA N^(6)-甲基腺苷修饰在砷致多器官损伤中的研究进展
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作者 张乾 满瑾 《中国医学科学院学报》 北大核心 2025年第6期1006-1014,共9页
砷是环境中广泛存在的有毒类金属元素,长期砷暴露导致机体皮肤、肝脏、肺脏、脑、卵巢等多器官的功能障碍,甚至癌变。RNA N^(6)-甲基腺苷(m^(6)A)是真核生物中最普遍的RNA表观遗传修饰,调控细胞的众多生理与病理过程。越来越多的研究表... 砷是环境中广泛存在的有毒类金属元素,长期砷暴露导致机体皮肤、肝脏、肺脏、脑、卵巢等多器官的功能障碍,甚至癌变。RNA N^(6)-甲基腺苷(m^(6)A)是真核生物中最普遍的RNA表观遗传修饰,调控细胞的众多生理与病理过程。越来越多的研究表明m^(6)A在砷诱导的皮肤、肝脏、肺脏、神经、生殖与胚胎等多器官和系统损伤中发挥重要的作用。本文归纳总结近年关于m^(6)A在砷致健康损害中的调控作用,为砷中毒的机制探究与治疗策略提供新思路。 展开更多
关键词 RNA N^(6)-甲基腺苷 RNA表观遗传修饰 毒作用机制
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Microbial Spectrum and Antibiotic Sensitivity Study of Postoperative Infections in Traumatology: Discussion on Optimizing Usage Strategies
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作者 Minxia Liao Runxiu Xia# Bin Han# 《Advances in Microbiology》 2025年第2期112-125,共14页
Objective: With the increasing volume of trauma surgery, postoperative infections have garnered significant attention, as they not only affect patient outcomes but also raise healthcare costs and the risk of bacterial... Objective: With the increasing volume of trauma surgery, postoperative infections have garnered significant attention, as they not only affect patient outcomes but also raise healthcare costs and the risk of bacterial resistance. This study aims to analyze the microbial spectrum and antibiotic sensitivity of patients with postoperative infections in trauma surgery, providing a basis for clinical treatment and optimizing antibiotic usage strategies in this context. Methods: A retrospective analysis was conducted on patients with traumatic infections who were hospitalized in the departments of spine surgery, upper limb surgery, and lower limb surgery from January 2022 to December 2024. Bacterial culture-positive specimens were analyzed for bacterial species and antibiotic sensitivity. Results: A total of 804 traumatic infection specimens were submitted for testing, including 538 male patients (ages 2 - 95 years) and 266 female patients (ages 4 - 94 years). Among these, 267 cases showed positive culture results, with 172 males (ages 2 - 93 years) and 95 females (ages 4 - 94 years). A total of 153 strains of Gram-negative (G−) bacteria and 114 strains of Gram-positive (G+) bacteria were identified. Among G− bacteria, Escherichia coli was the most frequently isolated (40 strains), followed by Pseudomonas aeruginosa (28 strains) and Enterobacter cloacae (28 strains). Among G+ bacteria, Staphylococcus aureus was the most prevalent (75 strains), followed by Enterococcus faecalis (15 strains) and Streptococcus pyogenes (8 strains). Antibiotic sensitivity testing revealed that the resistance rate of Staphylococcus aureus to penicillin was as high as 93.33%, while the resistance rate of Escherichia coli to trimethoprim-sulfamethoxazole was 57.5%. Conclusion: The main pathogens responsible for postoperative infections in traumatology are Escherichia coli and Staphylococcus aureus, with significant antibiotic resistance. In clinical treatment, antibiotics should be selected rationally based on bacterial spectrum and resistance patterns to improve treatment efficacy. 展开更多
关键词 Traumatic Infection Microbial spectrum Antibiotic Sensitivity Escherichia Coli Staphylococcus Aureus
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N^(6)-甲基腺苷修饰在植物响应逆境胁迫中的功能研究进展
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作者 许美秋 周晶晶 +4 位作者 李田 路梦涵 任艳歌 贾曼丽 押辉远 《江苏农业科学》 北大核心 2025年第7期1-10,共10页
植物在其生长过程中会不可避免地遭遇多种环境挑战,包括生物胁迫和非生物胁迫,这些因素显著限制了植物的生长并影响作物产量。在这些不利条件下,精确调控应激响应RNA的命运和功能对于植物的存活与适应至关重要。近期研究表明,RNA修饰在... 植物在其生长过程中会不可避免地遭遇多种环境挑战,包括生物胁迫和非生物胁迫,这些因素显著限制了植物的生长并影响作物产量。在这些不利条件下,精确调控应激响应RNA的命运和功能对于植物的存活与适应至关重要。近期研究表明,RNA修饰在基因表达、稳定性和翻译效率等方面起着重要作用。其中,N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)修饰作为真核生物mRNA中最普遍的内部修饰,对转录后调控发挥着关键作用。m^(6)A修饰是一个动态可逆的过程,涉及甲基转移酶(编码器,writer)、去甲基化酶(消码器,eraser)和m^(6)A识别蛋白(读码器,reader)的协同作用。随着研究技术的不断发展,特别是高通量测序技术和m^(6)A特异性免疫沉淀测序(m^(6)A-Seq)的应用,植物在响应各种胁迫时mRNA的m^(6)A修饰分布和模式逐渐明晰。本文综述了近年来m^(6)A修饰及其在植物应激响应中的动态、分布、调控和生物学功能方面的研究进展。这不仅加深了对m^(6)A修饰在植物响应外界不良环境中调控机制的理解,而且为开发新型耐胁迫作物品种提供了理论基础。 展开更多
关键词 N^(6)-甲基腺苷修饰 生物胁迫 非生物胁迫 m6A调节因子 基因表达调控
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Generating Social Interactions with Adolescents with Autism Spectrum Disorder, through a Gesture Imitation Game Led by a Humanoid Robot, in Collaboration with a Human Educator
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作者 Linda Vallée Malik Koné Olivier Asseu 《Open Journal of Psychiatry》 2025年第1期55-71,共17页
This article describes a pilot study aiming at generating social interactions between a humanoid robot and adolescents with autism spectrum disorder (ASD), through the practice of a gesture imitation game. The partici... This article describes a pilot study aiming at generating social interactions between a humanoid robot and adolescents with autism spectrum disorder (ASD), through the practice of a gesture imitation game. The participants were a 17-year-old young lady with ASD and intellectual deficit, and a control participant: a preadolescent with ASD but no intellectual deficit (Asperger syndrome). The game is comprised of four phases: greetings, pairing, imitation, and closing. Field educators were involved, playing specific roles: visual or physical inciter. The use of a robot allows for catching the participants’ attention, playing the imitation game for a longer period of time than with a human partner, and preventing the game partner’s negative facial expressions resulting from tiredness, impatience, or boredom. The participants’ behavior was observed in terms of initial approach towards the robot, positioning relative to the robot in terms of distance and orientation, reactions to the robot’s voice or moves, signs of happiness, and imitation attempts. Results suggest a more and more natural approach towards the robot during the sessions, as well as a higher level of social interaction, based on the variations of the parameters listed above. We use these preliminary results to draw the next steps of our research work as well as identify further perspectives, with this aim in mind: improving social interactions with adolescents with ASD and intellectual deficit, allowing for better integration of these people into our societies. 展开更多
关键词 Human-Robot Interaction (HRI) Autism spectrum Disorder (ASD) IMITATION Artificial Intelligence Gesture Recognition Social Interaction
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