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R/S Analyses of Some Geochemical Indexes for Tianshuihai Lake Core in West Kunlun Mountain and Their Environmental Implications
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作者 周厚云 余素华 +3 位作者 向明菊 朱照宇 李世杰 李炳元 《Chinese Journal Of Geochemistry》 EI CAS 2000年第2期138-144,共7页
With the decrease of global temperature, glacial epoch came over the earth and global climate fluctuated over a great range since the beginning of Quaternary. Paleoclimotologists of various countries have focussed att... With the decrease of global temperature, glacial epoch came over the earth and global climate fluctuated over a great range since the beginning of Quaternary. Paleoclimotologists of various countries have focussed attention to the periodic characteristics and dynamics of climatic fluctuation in the past many years (Berger, 1977; Imbrie and Hays, 1984; Ding Zhongli et al., 1990; Yu Zhiwei et al., 1992; Liu Youmei et al., 1996). Although some of the workers have paid their attention to the nonlinear characteristics of the global Quaternary environmental evolution (Nicolis and Nicolis, 1984; Lu Houyuan et al., 1993), it is worth while to do this kind of work in some special areas in the world, for example the Qinghai\|Tibet Plateau.\; Using R/S analysis, the authors calculated the Hurst indexes H of some geochemical proxies, including organic carbon, FeO, Fe\-2O\-3 and FeO/ Fe\-2O\-3, from the Tianshuihai Lake core in West Kunlun Mountain of the Qinghai\|Tibet Plateau. The proxies satisfy the Hurst law with H\-\{org.carbon\}=0.735, H\-\{Fe\-2O\-3\}=0.757, H\-\{FeO\}=0.848 and H\-\{FeO/Fe\-2O\-3\}=0.646. All the indexes are greater than 0.5, meaning that from 240 to 15 ka B.P., there were some long\|run dependencies\|persistence in the climatic and environmental evolution around the Tianshuihai Lake area. This is in accordance with the climate there from 240 to 15 ka B.P. (Yu Suhua et al., 1996). The paleo\|climate and paleo\|environment evolution around the Tianshuihai Lake area is of persistence as well as of fluctuation and is a combination of these two components. There are some differences between the four Hurst indexes, which probably resulted from the different intensities of persistence of the four proxies, organic carbon, FeO, Fe\-2O\-3 and FeO/ Fe\-2O\-3, or from the change of drainage system around the Tianshuihai Lake area from openness to closeness(Li Bingyuan et al., 1991; Sun Honglie, 1996; Shi Yafeng et al., 1998).\; The Qinghai\|Tibet plateau was the starter and sensor of the climatic and environmental variation of the surrounding areas (Yao Tandong et al., 1991; Feng Song et al., 1998) and some other scientists even regarded it as the driver and amplifier of global climatic variations (Pan Baotian and Li Jijun, 1996). The persistence in which the climate and environment around the Tianshuihai Lake area evolved from 240 to 15 ka B.P. is probably a function of the continuous uplift of the plateau in the same period of time. 展开更多
关键词 r/s分析 地球化学 古气候 古环境 昆仑山 抬升作用
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The nexus between the financial development and CO_(2) emissions:fresh evidence through time–frequency analyses
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作者 Faik Bilgili Erhan Muğaloğlu +3 位作者 Sevda Kuşkaya Javier Cifuentes‑Faura Kamran Khan Mohammed Alnour 《Financial Innovation》 2025年第1期1442-1463,共22页
Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and e... Climate change and environmental degradation threaten the world and global economic conditions.As one of countries’most important economic components,the financial sector might be an effective tool for reducing and even reversing environmental degradation.The financial sector can affect sustainability through its lending and investment practices.The sector can play a role in financing sustainable projects and businesses,helping reduce CO_(2) emissions.By aligning its financial objectives with environmental protection,the financial sector can support the transition to a more sustainable future by helping reduce environmental degradation’s negative impacts.This paper examines the domestic financial sector’s impact on CO_(2) emissions in the United States over the 1990:Q1–2022:Q3 period.In this research,the nexus between the domestic financial sector(total debt securities,loans,liabilities,and total financial assets)and Carbon dioxide emissions in the U.S.is investigated by Morlet wavelet analysis.Rest of the world:sector discrepancy transactions,rest of the world:debt securities and loans,gross domestic product,and the square of the gross domestic product,are control variables in the estimated models.Partial wavelet coherency analyses prove that the financial sector reduces CO_(2) emissions at the 5–8-year frequency band during different subsample periods.The financial sector’s instruments can be effective in struggling with climate change. 展开更多
关键词 Financial sector sustainable development Time-frequency analysis Wavelet analyses The U.s.
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基于R-S分解的混流式水轮机偏负荷尾水管涡带湍动能特性分析
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作者 黎志兴 庄建忠 +3 位作者 陈钰林 廖恒 董延春 冯建军 《水电能源科学》 北大核心 2026年第2期190-195,共6页
针对部分负荷工况下混流式水轮机尾水管涡带失稳问题,基于Liutex刚性涡量分解(R-S分解)与湍动能输运方程,揭示了尾水管涡带剪切涡量驱动湍动能的物理机制。结果表明,随着负荷的降低,尾水管内刚性涡量分布由尖峰向宽峰转变,涡核位置偏移... 针对部分负荷工况下混流式水轮机尾水管涡带失稳问题,基于Liutex刚性涡量分解(R-S分解)与湍动能输运方程,揭示了尾水管涡带剪切涡量驱动湍动能的物理机制。结果表明,随着负荷的降低,尾水管内刚性涡量分布由尖峰向宽峰转变,涡核位置偏移明显;剪切涡量通过速度梯度驱动湍动能生成,在尾水管内形成圆桶状剪切层,负荷降低时圆桶状剪切涡区域桶直径增大,剪切涡量分布的双峰间距增大,导致湍动能生成区扩展并加剧流动不稳定性。研究结果揭示了尾水管涡带涡结构与湍动能产生的耦合过程,发现螺旋涡带引发的湍动能与剪切涡量分布形态密切相关,为水轮机宽负荷运行优化及涡带的主动控制提供了理论支撑。 展开更多
关键词 混流式水轮机 尾水管涡带 r-s分解 湍流动能
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基于UPLC-MS/MS技术的(R/S)-2-(2-羟基丙酰氨基)-5-三氟甲基苯甲酸大鼠体内组织分布研究
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作者 高若芳 刘露露 +3 位作者 何丽娟 于治国 赵云丽 龙猜 《沈阳药科大学学报》 2026年第1期87-93,100,共8页
目的建立超高效液相色谱串联质谱法测定大鼠各组织中(R/S)-2-(2-羟基丙酰氨基)-5-三氟甲基苯甲酸[(R/S)-2-(2-hydroxypropanamido)-5-trifluoromethylbenzoic acid,R-/S-HFBA]浓度的方法,研究并比较(R/S)-HFBA在大鼠体内的组织分布特征... 目的建立超高效液相色谱串联质谱法测定大鼠各组织中(R/S)-2-(2-羟基丙酰氨基)-5-三氟甲基苯甲酸[(R/S)-2-(2-hydroxypropanamido)-5-trifluoromethylbenzoic acid,R-/S-HFBA]浓度的方法,研究并比较(R/S)-HFBA在大鼠体内的组织分布特征。方法SD大鼠单次灌胃给药后分别于0.5、3、8 h采取心、肝、脾、肺、肾、胃、小肠、胸腺、肌肉、脂肪等脏器或组织,采用UPLC-MS/MS法测定各组织中HFBA的浓度。结果大鼠单次灌胃给药后0.5 h即可在各组织中检测到HFBA。R-HFBA在各组织中浓度排列顺序为:小肠>胃>肾>肺>心>肝>脂肪>脾>胸腺>肌肉;S-HFBA在各组织中浓度排列顺序为:小肠>胃>肾>肝>肺>心>脾>脂肪>胸腺>肌肉。结论R/S-HFBA在大鼠体内分布广泛且迅速,R-HFBA与S-HFBA在肝脏、肾脏的浓度具有显著差异,推测是由于两者存在立体选择性差异。R/S-HFBA比2-(2-羟基丙酰氨基)-苯甲酸[2-(2-hydroxypropanamido)benzoic acid,HPABA]在大鼠体内保留的时间更长,三氟甲基的引入提高了HFBA的代谢稳定性。 展开更多
关键词 组织分布 超高效液相色谱串联质谱 (r/s)-2-(2-羟基丙酰氨基)-5-三氟甲基苯甲酸 手性药物
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Q345R钢焊缝在湿H_(2)S环境中的腐蚀机理与防护技术研究
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作者 王诗卉 《今日制造与升级》 2026年第1期4-7,共4页
针对石化设备用Q345R钢焊缝在湿H_(2)S环境中易发生氢致开裂和应力腐蚀开裂的问题,通过慢应变速率试验、电化学测试及微观表征,揭示焊缝区腐蚀敏感性高于母材的本质原因。研究表明:热影响区马氏体带(硬度HV280)与焊缝硫偏析(S含量0.015 ... 针对石化设备用Q345R钢焊缝在湿H_(2)S环境中易发生氢致开裂和应力腐蚀开裂的问题,通过慢应变速率试验、电化学测试及微观表征,揭示焊缝区腐蚀敏感性高于母材的本质原因。研究表明:热影响区马氏体带(硬度HV280)与焊缝硫偏析(S含量0.015 wt%)是氢陷阱密集区,HIC裂纹扩展速率达1.2×10^(-6) mm/s;提出焊后消应力处理(590℃×2 h)+焊后热处理+Ni-P镀层技术或焊后热处理+喷涂技术,使SSC门槛值(σ_(SSC))从35%提升至75%,设备寿命延长3倍。 展开更多
关键词 Q345r 焊缝腐蚀 湿H_(2)s 氢致开裂 NI-P镀层 喷涂
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Nuclear heating at the JSI TRIGA reactor:measurements and simulations
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作者 Klemen Ambrožič Hubert Carcreff +4 位作者 Vladimir Radulović Damien Fourmentel Christophe Destouches Nicolas Thiollay Luka Snoj 《Nuclear Science and Techniques》 2026年第4期243-253,共11页
Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collab... Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collaboration project between the French Atomic and Alternative Energy Commission(CEA) and Jožef Stefan Institute(JSI), Slovenia, have been performed at the JSI TRIGA reactor for the experimental assessment of nuclear heating in fission and fusion-relevant materials by the differential calorimetry technique, based on the CALMOS and CARMEN differential calorimeters, previously developed at CEA. The results of the first campaign performed at reactor powers between 100 and 250 kW have already been reported, highlighting some measurement difficulties. Therefore, the second campaign was performed at a lower reactor power of 30 kW to overcome these issues. Moreover, a computational analysis of the experiments was performed using the JSIR2S code package to calculate the nuclear heating levels. Both experiments and their reproduction by simulations are described in detail. We present a comparison of the previously reported measured nuclear heating values of the first campaign with the computational results, with consistent underestimation by simulations by 8–35%. We report the experimental and computational results for the second experimental campaign performed at a reactor power of 30 kW. The simulated heating values were in agreement with the measurements within the measured heating uncertainty, with simulated heating 2.7–11.3% lower than the experimental values. 展开更多
关键词 Nuclear heating Differential calorimeter r2s MCNP Eurofer97 TUNGsTEN
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基于S-O-R理论的AR滑雪镜用户采纳影响因素与界面设计研究
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作者 陆宁 刘家玲 岳子钰 《包装工程》 北大核心 2026年第2期523-535,共13页
目的针对AR滑雪镜等智能穿戴产品设计中用户采纳心理洞察不足、设计策略缺乏实证依据的问题,基于“刺激-机体-反应”(S-O-R)理论框架,系统性揭示AR滑雪镜的用户采纳机制并将关键心理路径转化为可操作的界面设计策略。方法首先构建整合... 目的针对AR滑雪镜等智能穿戴产品设计中用户采纳心理洞察不足、设计策略缺乏实证依据的问题,基于“刺激-机体-反应”(S-O-R)理论框架,系统性揭示AR滑雪镜的用户采纳机制并将关键心理路径转化为可操作的界面设计策略。方法首先构建整合成就探索、社交链接、安全感知等外部刺激(S)、感知价值与感觉寻求等机体变量(O),以及采纳意向(R)的理论模型,采用问卷调查与结构方程模型对各路径进行检验并分析感知价值的中介作用和感觉寻求的调节作用。在此基础上提出设计策略,进而构建符合AR视觉人机工学的界面信息架构与视觉规范指导设计。结果成就探索对采纳意向的直接影响最强,社交连接次之,而安全感知需通过感知价值的完全中介间接影响采纳意向。感觉寻求特质显著正向调节感知价值对采纳意向的影响,对高感觉寻求者的解释力更强。基于上述发现设计的界面方案在可用性测试中获得较高评价,其中安全感知维度评分最高,高感觉寻求用户对成就探索功能的评分显著高于低感觉寻求用户。结论构建了从“机制洞察-策略提炼-方案设计-效果验证”的完整设计闭环,揭示了AR滑雪镜用户采纳的心理驱动逻辑与差异化效应,形成了一套面向高风险运动场景的AR界面设计策略体系与实现路径,为AR滑雪镜及同类智能产品的用户导向创新提供理论依据与设计方法支持。 展开更多
关键词 s-O-r理论 Ar滑雪镜 用户采纳意向 界面设计策略
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重症肺炎患儿血清S100A8、sCD163、IL-1R1水平与预后的关系及临床意义
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作者 张重阳 王芳 李平 《现代临床医学》 2026年第1期32-36,共5页
目的:分析重症肺炎患儿血清S100A8、sCD163、IL-1R1水平与预后的关系及临床意义。方法:选取我院2022年2月至2024年8月收治的84例重症肺炎患儿为肺炎组,另选取同期84例健康体检儿童为对照组,比较两组入院时血清S100钙结合蛋白A8(S100A8)... 目的:分析重症肺炎患儿血清S100A8、sCD163、IL-1R1水平与预后的关系及临床意义。方法:选取我院2022年2月至2024年8月收治的84例重症肺炎患儿为肺炎组,另选取同期84例健康体检儿童为对照组,比较两组入院时血清S100钙结合蛋白A8(S100A8)、可溶性血红蛋白清道夫受体(sCD163)、白细胞介素-1受体1(IL-1R1)水平。根据预后情况将肺炎组患儿分为预后良好组(n=62)、预后不良组(n=22),对比不同预后患儿入院时及治疗14 d时的S100A8、sCD163、IL-1R1水平并分析其相关性,判断联合检测对患儿疾病预后的预测价值。结果:肺炎组血清S100A8、sCD163、IL-1R1水平显著高于对照组(P<0.05);入院时、治疗14 d时,预后不良组血清S100A8、sCD163、IL-1R1水平高于预后良好组(P<0.05);血清S100A8、sCD163、IL-1R1水平与患儿疾病预后呈正相关(P<0.05);入院时、治疗14 d时三者联合检测预测患儿预后不良的曲线下面积分别为0.841、0.870;高水平血清S100A8、sCD163、IL-1R1患儿发生预后不良的危险度是低水平患儿的2~4倍(P<0.05)。结论:血清S100A8、sCD163、IL-1R1水平与重症肺炎患儿预后密切相关,三者联合检测可作为评估重症肺炎患儿预后的潜在生物标志物。 展开更多
关键词 s100A8 sCD163 IL-1r1 重症肺炎 疾病预后
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靶向晚期前列腺癌中FOXA1 R219S突变体的药物发现
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作者 林慧 李冬晴 +1 位作者 王文正 郭海洋 《生命的化学》 2026年第1期142-153,共12页
晚期前列腺癌易复发、转移,临床尚无有效治疗手段,亟需发现高效靶向药物。转录因子FOXA1突变在二代抗雄药物耐受的前列腺癌中显著富集,与肿瘤恶性进展高度相关,但目前尚无针对突变型FOXA1蛋白的小分子抑制剂报道。本研究旨在利用虚拟筛... 晚期前列腺癌易复发、转移,临床尚无有效治疗手段,亟需发现高效靶向药物。转录因子FOXA1突变在二代抗雄药物耐受的前列腺癌中显著富集,与肿瘤恶性进展高度相关,但目前尚无针对突变型FOXA1蛋白的小分子抑制剂报道。本研究旨在利用虚拟筛选结合表面等离子共振(surface plasmon resonance,SPR)和IC_(50)、EMSA、RT-qPCR等功能验证实验,筛选FOXA1 R219S突变型蛋白的靶向药物。通过分析临床样本中FOXA1的突变位点及频率,明确热点突变R219S、R219C、R261C、R261G和R261S,并通过药物虚拟筛选发现了一系列针对热点突变的小分子抑制剂。其中,R219S突变在晚期神经内分泌性前列腺癌(neuroendocrine prostate cancer,NEPC)中显著富集,并且该突变促进了前列腺癌恶性增殖及转移。本研究聚焦该突变,首先明确药物靶向FOXA1野生型和R219S突变型蛋白的结合口袋及附近的关键氨基酸位点;为体外验证药物与蛋白质的结合能力,对GST-FOXA1-His蛋白进行异源表达和纯化,并通过SPR实验证实4种药物(咪唑烷基脲、氨磷汀、曲氟尿苷和羟基积雪草苷)选择性结合FOXA1 R219S蛋白而不结合FOXA1 WT蛋白。其中,EMSA结果发现,咪唑烷基脲、氨磷汀和曲氟尿苷均能够竞争性抑制FOXA1 R219S蛋白与DNA的结合;CCK8结果发现,曲氟尿苷对前列腺癌细胞具有较强的杀伤效果(IC_(50)=15.4μmol/L)。综上所述,本研究初步筛选到FOXA1 R219S选择性靶向的药物,为晚期前列腺癌靶向药物的开发奠定了基础。 展开更多
关键词 FOXA1 r219s 虚拟筛选 sPr 前列腺癌 靶向治疗
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MAPT-isoform 0N3R is essential for human brain development:Loss-of-function for novel TAU-associated disease paradigms
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作者 Hans Zempel 《Neural Regeneration Research》 2026年第8期3349-3351,共3页
Hans Zempel1,2 TAU,a microtubule-associated protein,encoded by the microtubule-associated protein tau(MAPT)gene,is a central regulator of microtubule stability and axonal function in the human brain,with its pathologi... Hans Zempel1,2 TAU,a microtubule-associated protein,encoded by the microtubule-associated protein tau(MAPT)gene,is a central regulator of microtubule stability and axonal function in the human brain,with its pathological aggregation representing a hallmark of Alzheimer’s disease and related tauopathies.Despite extensive research into the role of TAU in neurodegeneration,its essentiality for human brain development has remained unclear.This perspective synthesizes recent genetic,molecular,and cellular evidence to demonstrate that the human brain-specific TAU isoform 0N3R is indispensable for proper neurodevelopment,pointing to loss-of-function of this isoform as a novel paradigm for TAU-associated disease.Alternative splicing of MAPT generates six brain-specific TAU isoforms,with 0N3R being exclusively expressed during fetal brain development.Analysis of large-scale human genetic datasets(gnomAD v4.0.0)reveals a high probability of loss-of-function intolerance(pLI=0.96)for the 0N3R isoform.This is in stark contrast to the canonical Matched Annotation from the NCBI and EMBL-EBI(MANE)transcript and peripheral“Big TAU,”both of which are tolerant to loss-of-function mutations.This intolerance is further supported by the scarcity of loss-of-function mutations in 0N3R-encoding exons and high missense constraint scores,suggesting strong evolutionary selection against disruption of this isoform.Functional studies using human induced pluripotent stem cell-derived cortical neurons with CRISPR-Cas9-mediated MAPT knockout reveal that,unlike in murine models where compensation by other microtubule-associated proteins occurs,loss of TAU in human neurons leads to deficits in neurite outgrowth,axon initial segment shortening,and a trend toward hyperexcitability,accompanied by broad transcriptomic changes affecting genes involved in microtubule organization and synaptic structure.Remarkably,re-expression of any of the six human brain-specific TAU isoforms rescues these phenotypes,underscoring their functional redundancy during development.These findings position the 0N3R isoform as essential for human brain development and suggest that loss-of-function mutations affecting this isoform likely result in neurodevelopmental impairment,potentially manifesting as intellectual disability without overt dysmorphic features.This contrasts with the apparent tolerance to MAPT loss-of-function in mice and peripheral tissues,highlighting a critical species-and isoform-specific requirement for TAU in human neurodevelopment.The hypothesis of 0N3R-TAU loss-of-function intolerance opens new avenues for understanding neurodevelopmental disorders and refines the conceptual framework of TAU-associated disease mechanisms beyond toxic gain-of-function. 展开更多
关键词 0N3r isoform alternative splicing Alzheimers disease intellectual disability neurodevelopmental disorders TAU protein TAUOPATHY
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Endoscopic submucosal dissection versus endoscopic mucosal resection for early esophageal neoplasia:A systematic review and meta-analysis
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作者 Hur Abbas Maria Murtaza +11 位作者 Khadija Azeem Maryam Asad Maham Shakeel Irtaza Hassan Manail Asif Haya Kashif Lia Anwar Maham Abid Hasan Anwar Hassan Ali Satesh Kumar Mahima Khatri 《Laparoscopic, Endoscopic and Robotic Surgery》 2025年第4期191-200,共10页
Objective:Esophageal carcinoma(EC)is a primary global health concern,ranking as the eighth most common cancer and the sixth leading cause of cancer-related mortality.Endoscopic mucosal resection(EMR)and endoscopic sub... Objective:Esophageal carcinoma(EC)is a primary global health concern,ranking as the eighth most common cancer and the sixth leading cause of cancer-related mortality.Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)are widely used to manage early-stage EC and Barrett’s esophagus.However,their comparative efficacyand safety remain debated.This study aims to systematically compare the safety and efficacyof ESD and EMR in the treatment of early EC and Barrett’s esophagus.Methods:A systematic review and meta-analysis were conducted following the PRISMA 2020 guidelines.Databases,including MEDLINE(via PubMed),Google Scholar,and the Cochrane Library were searched for studies published up to October 2024.Twenty-two studies involving 3309 patients(1425 with ESD and 1884 with EMR)met the inclusion criteria.The outcomes assessed included en bloc resection,R0 resection,curative resection,local recurrence,bleeding,perforation,and stricture formation.Risk ratios(RR)with 95%CIs were calculated via a random-effects model via RevMan 5.4.Results:ESD significantlyoutperformed EMR in en bloc resection(RR=2.22,95%CI:1.69–2.90;p<0.001),R0 resection(RR=1.93,95%CI:1.28–2.91;p=0.002),and curative resection rates(RR=2.29,95%CI:1.52–3.46;p<0.001).ESD was associated with lower local recurrence in patients with squamous cell carcinoma(SCC)(RR=0.13,95%CI:0.06–0.30;p<0.001),whereas recurrence was greater in patients with Barrett’s esophagus(RR=1.67,95%CI:1.30–2.14;p<0.001).No significant difference was observed in bleeding rates;however,ESD was associated with a greater risk of perforation(RR=2.94,95%CI:1.31–6.60;p=0.009).Conclusion:ESD is more effective than EMR in achieving complete and curative resections for early EC and SCC,particularly for lesions>20 mm.However,it has a higher complication rate,especially perforation.Careful patient selection and procedural expertise are essential when choosing between the two techniques. 展开更多
关键词 Esophageal carcinoma Barrett’s esophagus Endoscopic submucosal dissection Endoscopic mucosal resection En bloc resection r0 resection Curative resection
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THE WREATH PRODUCT GROUP FOR NMR SPECTRA ANALYSES OF MOLECULA WITH S_4[S_2]SYMMETRY
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作者 Wei Liang ZHOU Xiao Chun HE Yong Ren HUANG East China Normal University,Shanghai,200062 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期325-328,共4页
This paper presents a character table of S_4 wr S_2 wreath product group.Using this character table,~1H or ^(13)C NMR spectra analysis of molecula with S_4[S_2]symmetry,especially simplification of the secular determi... This paper presents a character table of S_4 wr S_2 wreath product group.Using this character table,~1H or ^(13)C NMR spectra analysis of molecula with S_4[S_2]symmetry,especially simplification of the secular determinant equation will be easy to carry out. Molecules with S_4[S_2]symmetry,are exemplified by octaphenylcyclo- tetrasiloxane and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine chromium (Ⅲ)chloride. 展开更多
关键词 NMr UC this THE WrEATH PrODUCT GrOUP FOr NMr sPECTrA analyses OF MOLECULA WITH s4[s2]sYMMETrY 公寸
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Unraveling one billion years of geological evolution of the southeastern Amazonia Craton from detrital zircon analyses
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作者 Camille Rossignol Paul Yves Jean Antonio +8 位作者 Francesco Narduzzi Eric Siciliano Rego Lívia Teixeira Romário Almeida de Souza Janaína N.Ávila Marco A.L.Silva Cristiano Lana Ricardo I.F.Trindade Pascal Philippot 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第5期129-152,共24页
Despite representing one of the largest cratons on Earth,the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events h... Despite representing one of the largest cratons on Earth,the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events have obscured initial information.In this study,we investigated the sedimentary archives of the Carajás Basin to unravel the early geological evolution of the southeastern Amazonia Craton.The Carajás Basin contains sedimentary rocks that were deposited throughout a long period spanning more than one billion years from the Mesoarchean to the Paleoproterozoic.The oldest archives preserved in this basin consist of a few ca.3.6 Ga detrital zircon grains showing that the geological roots of the Amazonia Craton were already formed by the Eoarchean.During the Paleoarchean or the early Mesoarchean(<3.1 Ga),the Carajás Basin was large and rigid enough to sustain the formation and preservation of the Rio Novo Group greenstone belt.Later,during the Neoarchean,at ca.2.7 Ga,the southeastern Amazonia Craton witnessed the emplacement of the Parauapebas Large Igneous Province(LIP)that probably covered a large part of the craton and was associated with the deposition of some of the world largest iron formations.The emplacement of this LIP immediately preceded a period of continental extension that formed a rift infilled first by iron formations followed by terrigenous sediments.This major change of sedimentary regime might have been controlled by the regional tectonic evolution of the Amazonia Craton and its emergence above sea-level.During the Paleoproterozoic,at ca.2.1 Ga,the Rio Fresco Group,consisting of terrigenous sediments from the interior of the Amazonia Craton,was deposited in the Carajás Basin.At that time,the Amazonian lithosphere could have either underwent thermal subsidence forming a large intracratonic basin or could have been deformed by long wavelength flexures that induced the formation of basins and swells throughout the craton under the influence of the growing Transamazonian mountain belt. 展开更多
关键词 Carajás Basin Chemical Abrasion–LA-ICP-Ms analyses Age distribution comparison Parauapebas Large Igneous Province Transamazonian orogeny
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5米S-SAR卫星固态有源馈电网络设计与实现
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作者 赵海洋 吕慎刚 +2 位作者 李阳斌 刘洪斌 郑新 《航天器工程》 北大核心 2025年第3期103-110,共8页
针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、... 针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、波束控制单元等来实现射频大功率有源馈电和多极化工作模式。通过对氮化镓(GaN)化合物半导体高功率器件的应用,实现了馈电系统的高功率、高效率和高可靠性等性能指标要求。通过机热一体化设计,形成了一种具有良好力学性能和热学性能的固态有源馈电网络系统。项目完成了规定的环境试验考核,并提交5米S-SAR卫星装星应用验证,结果表明:该固态有源馈电网络满足卫星的使用要求。 展开更多
关键词 5米s频段合成孔径雷达卫星 固态有源馈电网络 T/r组件 氮化镓化合物半导体
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基于S-O-R模型的在校研究生数字囤积行为识别研究 被引量:1
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作者 徐绪堪 闫瑛洁 高伟 《情报科学》 北大核心 2025年第1期161-168,共8页
【目的/意义】大数据时代数据剧增的同时数字囤积行为也日益严重,尤其是在校研究生群体,数字囤积表现尤为显著。日益增强的数字囤积行为严重阻碍了在校研究生群体科研能力的提升,本文通过数字囤积行为识别引导在校研究生有序高效进行数... 【目的/意义】大数据时代数据剧增的同时数字囤积行为也日益严重,尤其是在校研究生群体,数字囤积表现尤为显著。日益增强的数字囤积行为严重阻碍了在校研究生群体科研能力的提升,本文通过数字囤积行为识别引导在校研究生有序高效进行数据积累,提升在校研究生数据素养,促进其更快地适应学术研究氛围。【方法/过程】针对在校研究生数据无序积累、使用率低下、数据转化能力不足等问题,使用访谈法收集56条数据,利用扎根理论对在校研究生数字囤积行为进行识别,基于S-O-R模型构建在校研究生数字囤积行为识别模型。【结果/结论】最终得出16个范畴、56个概念并形成在校研究生数字囤积行为识别模型,明晰在校研究生数字囤积行为的影响因素与表现并对其数字囤积行为进行分类,给出增强共享数据意识、定期进行心理访谈、改善数据积累习惯等针对性建议。【创新/局限】文章将S-O-R模型应用于数字囤积行为的研究,将心理学概念与情报学分析方法相结合。下一步将对不同环境下的不同群体数字囤积行为进行针对性、拓展性研究,尤其是对数字囤积行为的深度量化研究。 展开更多
关键词 在校研究生 数字囤积 行为识别 s-O-r模型 扎根理论
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大学生信息成瘾行为的触发路径与干预策略:基于S-O-R理论视角 被引量:1
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作者 张晨 姜为翰 钱鹏博 《科技情报研究》 2025年第1期118-130,共13页
[目的/意义]文章以大学生为研究对象,探究该群体信息成瘾行为的影响机制,为大学生信息成瘾行为的预防和管理提供价值参考。[方法/过程]引入刺激-机体-反应(S-O-R)理论,利用文献梳理总结大学生信息成瘾过程中的外部刺激,深度剖析机体在... [目的/意义]文章以大学生为研究对象,探究该群体信息成瘾行为的影响机制,为大学生信息成瘾行为的预防和管理提供价值参考。[方法/过程]引入刺激-机体-反应(S-O-R)理论,利用文献梳理总结大学生信息成瘾过程中的外部刺激,深度剖析机体在成瘾过程中产生的认知心理,构建大学生信息成瘾行为理论模型,运用结构方程模型实证分析大学生信息成瘾的触发路径。[结果/结论]研究结果表明,信息过载、间歇性奖励和行为管理会显著正向影响大学生的不确定性回避,进而导致大学生信息成瘾。同时,信息过载也会使大学生产生信息焦虑,信息焦虑显著正向影响大学生信息成瘾行为。面向高等院校、大学生群体和科技企业,提出针对性建议与对策,有助于完善高等院校管理体系,促进学生适应信息化环境,推动高等教育事业更好发展。 展开更多
关键词 信息成瘾 s-O-r理论 结构方程模型 干预策略
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基于S-O-R模型的大学生网络社交跨圈层意愿研究 被引量:1
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作者 曲峡 王育晓 闫星宇 《高校辅导员学刊》 2025年第3期60-68,98,99,共11页
基于刺激-机体-反应(S-O-R)模型,深入探讨大学生网络社交跨圈层意愿的形成机制,综合运用信息生态理论分析信息窄化、信息过载、圈层文化、个性化推荐和信息素养等刺激因素如何影响其跨圈层意愿进而对跨圈层行为产生影响。在此基础上,提... 基于刺激-机体-反应(S-O-R)模型,深入探讨大学生网络社交跨圈层意愿的形成机制,综合运用信息生态理论分析信息窄化、信息过载、圈层文化、个性化推荐和信息素养等刺激因素如何影响其跨圈层意愿进而对跨圈层行为产生影响。在此基础上,提出相应研究假设并采用结构方程模型(SEM)进行验证,结果表明:信息窄化对跨圈层意愿的负向影响不显著,圈层文化对跨圈层意愿具有负向影响,信息过载、个性化推荐和信息素养对跨圈层意愿具有正向影响,大学生跨圈层意愿对其跨圈层行为产生显著正向影响。研究结果为打破信息茧房、促进大学生跨圈层交流提供了理论支持与实践路径,为高校思想政治教育工作创新提供了实证依据。 展开更多
关键词 大学生 网络社交 s-O-r模型 跨圈层意愿 圈层文化
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5米S-SAR卫星总体设计与技术创新
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作者 王国良 朱雅琳 +6 位作者 李志刚 王迪 郑泽星 陈娟 梅名宣 王帅雷 贾松霖 《航天器工程》 北大核心 2025年第3期60-66,共7页
5米S频段合成孔径雷达(S-SAR)01/02卫星是最高分辨率为5 m、工作在S频段的SAR卫星,星上配置有S频段SAR载荷及星上应急数据实时处理设备,对应急区域的SAR数据进行星上实时成像处理和检测。文章简述卫星总体设计方案;总结有效载荷设计技... 5米S频段合成孔径雷达(S-SAR)01/02卫星是最高分辨率为5 m、工作在S频段的SAR卫星,星上配置有S频段SAR载荷及星上应急数据实时处理设备,对应急区域的SAR数据进行星上实时成像处理和检测。文章简述卫星总体设计方案;总结有效载荷设计技术和应用创新点,尤其是大口径构架式双焦点椭球抛物面反射器、基于国产化S频段大功率GaN器件的收发(T/R)组件、基于星上数据实时处理功能的应急应用新模式。卫星在轨测试和应用情况表明:5米S-SAR 01/02卫星星地一体化性能均满足设计指标要求,为国家应急管理、生态环境保护业务化应用提供重要技术支撑。反射面体制全极化5米S-SAR卫星总体设计技术和技术创新,可为S频段SAR卫星技术和应用的发展提供参考。 展开更多
关键词 5米s频段合成孔径雷达卫星 多极化相控阵馈源 抛物面反射器 s频段收发组件 应急应用
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基于S-O-R模型的信息素养教育影响体育行为的中介路经研究 被引量:1
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作者 张婕 王慧琳 《山东体育科技》 2025年第1期9-14,共6页
教育干预是维持长期体育行为的重要因素之一。基于S-O-R模型,从外部刺激和内部转化,探索信息素养教育模式影响体育行为的模型及路径。以信息素养课程学习者为研究对象进行实证研究,发现信息素养教育从体育信息的视角提供的知识支持、技... 教育干预是维持长期体育行为的重要因素之一。基于S-O-R模型,从外部刺激和内部转化,探索信息素养教育模式影响体育行为的模型及路径。以信息素养课程学习者为研究对象进行实证研究,发现信息素养教育从体育信息的视角提供的知识支持、技术支持和环境支持,通过个体感知后内化为参与意愿正向影响体育行为。 展开更多
关键词 s-O-r模型 信息素养教育 体育行为 体育参与意愿 个体感知
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(s)-氯胺酮通过调节ATP/P2X7R轴增强M2型小胶质细胞极化发挥抗卒中作用
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作者 王瑞 陈永学 +1 位作者 崔栋然 武琼 《热带医学杂志》 2025年第1期44-48,I0002,共6页
目的基于三磷酸腺苷/激活嘌呤能受体(ATP/P2X7R)信号探究(s)-氯胺酮发挥抗卒中的作用机制。方法将SD大鼠随机分为假手术组、模型组、(s)-氯胺酮低剂量组(0.8 mg/kg)、(s)-氯胺酮中剂量组(1.6 mg/kg)、(s)-氯胺酮高剂量组(3.2 mg/kg),每... 目的基于三磷酸腺苷/激活嘌呤能受体(ATP/P2X7R)信号探究(s)-氯胺酮发挥抗卒中的作用机制。方法将SD大鼠随机分为假手术组、模型组、(s)-氯胺酮低剂量组(0.8 mg/kg)、(s)-氯胺酮中剂量组(1.6 mg/kg)、(s)-氯胺酮高剂量组(3.2 mg/kg),每组18只。采用Longa线栓法制备缺血性卒中(IS)模型,缺血期间尾静脉注射(s)-氯胺酮。24 h后开展神经功能评分,将大鼠处死,取脑组织开展TTC染色评估脑梗死区域面积,免疫荧光染色检测小胶质细胞极化,ELISA试剂盒检测ATP与二磷酸腺苷(ADP)含量,Western blot检测P2X7R与各个炎症反应蛋白表达情况。结果与假手术组相比,模型组大鼠神经功能评分增加,出现局部梗死区域。与模型组相比,(s)-氯胺酮低剂量组和(s)-氯胺酮中剂量组大鼠神经功能评分减少(t=7.387、10.713,P均<0.05),局部梗死区域面积占比减少(t=7.156、8.446,P均<0.05),且小胶质细胞活化标记蛋白离子钙结合接头分子1(iba1)表达减少(t=7.471、7.301,P均<0.05),CD16表达降低(t=8.985、8.601,P均<0.05),精氨酸酶1(Arg1)表达升高(t=5.733、11.161,P均<0.05),差异均有统计学意义。此外,与模型组相比,(s)-氯胺酮低剂量组和(s)-氯胺酮中剂量组大鼠脑组织中ATP和ADP含量增加,P2X7R、含NLR家族Pyrin域蛋白3(NLRP3)与磷酸化核因子-κB(p-NF-κB)表达减少,差异均有统计学意义(P均<0.05),而(s)-氯胺酮高剂量组大鼠各项指标无明显变化(P>0.05)。结论亚麻剂量(s)-氯胺酮能够明显提高ATP释放,抑制P2X7R活化,减少M1型、促进M2型小胶质细胞极化,发挥抗缺血性卒中保护作用。 展开更多
关键词 亚麻剂量 (s)-氯胺酮 缺血性卒中 P2X7r
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