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稀土高熵氧化物用于能源和环境催化
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作者 李雨鸥 王克 +6 位作者 王笑妹 王子健 徐晶 赵梦 汪啸 宋术岩 张洪杰 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期54-70,共17页
随着工业技术的快速发展,能源短缺与环境污染问题日益凸显,对人类生活和社会经济发展造成了严重影响.在这一背景下,加速能源系统转型、积极开发与利用可再生能源变得至关重要,成为当前研究领域的热点.同时,消除环境中的有毒有害物质也... 随着工业技术的快速发展,能源短缺与环境污染问题日益凸显,对人类生活和社会经济发展造成了严重影响.在这一背景下,加速能源系统转型、积极开发与利用可再生能源变得至关重要,成为当前研究领域的热点.同时,消除环境中的有毒有害物质也具有较高的研究价值,对维护生态平衡和人类健康具有重要意义.催化技术因在去除污染物和能源转换方面具有巨大的应用潜力而备受关注.其中,高熵氧化物因其具有多样可调的晶体结构和丰富的表面活性位点,展现出较好的催化性能,从而备受研究者关注.此外,稀土元素因以其相近的离子半径、独特的电子轨道和可变的氧化态,常被用作高熵氧化物的组成元素.通过引入稀土元素,可以有效改善高熵氧化物的结构和性能.近年来,稀土高熵氧化物在催化应用中取得较多的研究成果,然而却缺少对该方面工作系统全面的综述.本文旨在系统总结稀土高熵氧化物的结构特点、合成方法及其在催化领域的应用,以期为该领域的进一步发展提供有益的参考.本文从结构、合成及应用等方面,对稀土高熵氧化物在催化领域的研究进展进行了总结.首先,详细介绍了钙钛矿型、萤石型和烧绿石型三种类型稀土高熵氧化物的结构特征,并探讨了结构对催化反应过程的重要影响.研究表明,多组分的高熵效应保证了单相固溶体的形成和高温下的催化稳定性,而晶格畸变效应则促进了氧空位等活性位点的形成,进而提升了催化活性.复杂多变的晶体结构导致了离子扩散延迟,这也使得高熵材料在催化过程中具有优异稳定性.此外,揭示了多种元素间的协同作用对催化性能的提升作用.值得一提的是,非等摩尔金属成分也可形成高熵氧化物,为稀土高熵氧化物研究开辟了新的方向.其次,讨论了稀土高熵氧化物的合成方法,主要包括固相反应合成法、喷雾热解法、化学共沉淀法和溶液燃烧法,合成方法的选择和优化对于建立高熵系统至关重要.目前,众多简单快速的合成方法已取代耗时耗力的合成过程,为稀土高熵氧化物的制备提供了便利.最后,重点概述了稀土高熵氧化物在电催化、热催化和光催化中的应用进展,并详细介绍了多元素可调材料对反应活性的影响.同时,指出了稀土高熵氧化物未来发展所面临的挑战,并提出了相应的应对策略,以期为高熵系统的理论研究提供有力支撑.综上,稀土高熵氧化物因其复杂结构而展现出丰富的潜在催化反应性能,具有巨大的应用潜力.未来研究可以加强开发设计、精准调控结构以及深入分析反应机理,从而提升高熵氧化物的催化性能.希望本文能够为稀土高熵氧化物催化体系研究提供有益的参考. 展开更多
关键词 稀土 高熵氧化物 催化 单相结构 合成
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斜纹夜蛾高致病力生防真菌的筛选与鉴定
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作者 田艺帆 张正坤 +5 位作者 隋丽 赵宇 路杨 孟钊 石旺鹏 李启云 《中国生物防治学报》 CSCD 北大核心 2024年第2期282-290,共9页
本研究从斜纹夜蛾幼虫僵虫中分离并纯化虫生真菌,得到6株昆虫病原真菌,利用形态学和分子生物学方法对上述真菌进行鉴定,采用浸渍法测定6株真菌对斜纹夜蛾2龄幼虫的毒力。结果表明,6株虫生真菌分别为2株球孢白僵菌Beauveria bassiana,以... 本研究从斜纹夜蛾幼虫僵虫中分离并纯化虫生真菌,得到6株昆虫病原真菌,利用形态学和分子生物学方法对上述真菌进行鉴定,采用浸渍法测定6株真菌对斜纹夜蛾2龄幼虫的毒力。结果表明,6株虫生真菌分别为2株球孢白僵菌Beauveria bassiana,以及莱氏绿僵菌Metarhizium rileyi,木贼镰刀菌Fusarium equiseti,曲霉菌Aspergillus nomiae和糙孢蓝状菌Talaromyces trachyspermus各1株。在1×10^(8)个孢子/m L浓度下,LT50分别为4.737 d,4.543 d,1.343 d,2.086 d,2.212 d和2.351 d,6株虫生真菌对斜纹夜蛾2龄幼虫均表现出较强致病力,其中莱氏绿僵菌表现最好。本研究首次报道了镰刀菌和曲霉菌能够感染斜纹夜蛾,并首次发现糙孢蓝状菌能够感染昆虫。 展开更多
关键词 斜纹夜蛾 虫生真菌 毒力
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Investigation of hydroxyl-terminated polybutadiene propellant breaking characteristics and mechanism impacted by submerged cavitation water jet 被引量:1
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作者 Wenjun Zhou meng zhao +3 位作者 Bo Liu Youzhi Ma Youzhi Zhang Xuanjun Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期559-572,共14页
A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impac... A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impact are unclear.This study aims to understand those impact breaking mechanisms.The hydroxyl-terminated polybutadiene(HTPB)propellant was chosen as the research material,and a self-designed test system was used to conduct impact tests at four different working pressures.The high-speed camera characterized crack propagation,and the DIC method calculated strain change during the impact process.Besides,micro and macro fracture morphologies were characterized by scanning electron microscope(SEM)and computed tomography(CT)scanning.The results reveal that the compressive strain concentration region locates right below the nozzle,and the shear strain region distributes symmetrically with the jet axis,which increases to 4% at first 16th ms,the compressive strain rises to 2% and 6% in the axial and transverse direction,respectively.The two tensile cracks formed first at the compression strain concentrate region,and there generate many shear cracks around the tensile cracks,and those shear cracks that develop and aggregate cause the cracks to become wider and cut through the tensile cracks,forming the tensile-shear cracks and the impact parts eventually fail.The HTPB propellant forms a breaking hole shaped conical after impact 10 s.The mass loss increases by 17 times at maximum,with the working pressure increasing by three times.Meanwhile,the damage value of the breaking hole remaining on the surface increases by 7.8 times while 2.9 times in the depth of the breaking hole.The breaking efficiency is closely affected by working pressures.The failure modes of HTPB impacted by SCWJ are classified as tensile crack-dominated and tensile-shear crack-dominated damage mechanisms. 展开更多
关键词 Submerged cavitation water jet Hydroxyl-terminated polybutadiene propellant Breaking characteristics Failure modes
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Paeoniflorin ameliorates chronic colitis via the DR3 signaling pathway in group 3 innate lymphoid cells
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作者 Shaowei Huang Xueqian Xie +11 位作者 Bo Xu Zengfeng Pan Junjie Liang Meiling Zhang Simin Pan Xiaojing Wang meng zhao Qing Wang Jinyan Chen Yanyang Li Lian Zhou Xia Luo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期889-901,共13页
Inhibiting the death receptor 3(DR3)signaling pathway in group 3 innate lymphoid cells(ILC3s)presents a promising approach for promoting mucosal repair in individuals with ulcerative colitis(UC).Paeoniflorin,a promine... Inhibiting the death receptor 3(DR3)signaling pathway in group 3 innate lymphoid cells(ILC3s)presents a promising approach for promoting mucosal repair in individuals with ulcerative colitis(UC).Paeoniflorin,a prominent component of Paeonia lactiflora Pall.,has demonstrated the ability to restore barrier function in UC mice,but the precise mechanism remains unclear.In this study,we aimed to delve into whether paeoniflorin may promote intestinal mucosal repair in chronic colitis by inhibiting DR3 signaling in ILC3s.C57BL/6 mice were subjected to random allocation into 7 distinct groups,namely the control group,the 2%dextran sodium sulfate(DSS)group,the paeoniflorin groups(25,50,and 100 mg/kg),the anti-tumor necrosis factor-like ligand 1A(anti-TL1A)antibody group,and the IgG group.We detected the expression of DR3 signaling pathway proteins and the proportion of ILC3s in the mouse colon using Western blot and flow cytometry,respectively.Meanwhile,DR3-overexpressing MNK-3 cells and 2%DSS-induced Rag1^(-/-)mice were used for verification.The results showed that paeoniflorin alleviated DSS-induced chronic colitis and repaired the intestinal mucosal barrier.Simultaneously,paeoniflorin inhibited the DR3 signaling pathway in ILC3s and regulated the content of cytokines(interleukin-17A,granulocyte-macrophage colony stimulating factor,and interleukin-22).Alternatively,paeoniflorin directly inhibited the DR3 signaling pathway in ILC3s to repair mucosal damage independently of the adaptive immune system.We additionally confirmed that paeoniflorin-conditioned medium(CM)restored the expression of tight junctions in Caco-2 cells via coculture.In conclusion,paeoniflorin ameliorates chronic colitis by enhancing the intestinal barrier in an ILC3-dependent manner,and its mechanism is associated with the inhibition of the DR3 signaling pathway. 展开更多
关键词 PAEONIFLORIN Ulcerative colitis Intestinal mucosal barrier DR3 signaling pathway Group 3 innate lymphoid cells
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A Large-Scale Group Decision Making Model Based on Trust Relationship and Social Network Updating
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作者 Rongrong Ren Luyang Su +2 位作者 Xinyu meng Jianfang Wang meng zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期429-458,共30页
With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that consid... With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted. 展开更多
关键词 Large-scale group decision making social network updating trust relationship group consensus feedback mechanism
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Causal relationship between circulating vitamin C and 25-hydroxyvitamin D concentrations and common mental disorders-a Mendelian randomization study
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作者 Yuanyuan Wang Lirong Dong +8 位作者 meng zhao Shiyu Yin Pan Da Dengfeng Xu Yifei Lu Jiayue Xia Niannian Wang Shaokang Wang Guiju Sun 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1877-1885,共9页
Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D... Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality. 展开更多
关键词 Circulating vitamin C 25-Hydroxyvitamin D Mental disorder Mendelian randomization
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核壳/蛋黄壳纳米反应器用于串联催化
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作者 赵梦 徐晶 +1 位作者 宋术岩 张洪杰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第7期83-108,共26页
串联催化在工业生产中具有重要意义.串联催化剂将两个或多个具有不同反应活性的明确活性位点整合到一个催化剂单元中,预先设计的催化反应可以在相应的活化位点依次发生,即反应物在第一个位点被激活,产生的中间体将迁移到下一个位点,直... 串联催化在工业生产中具有重要意义.串联催化剂将两个或多个具有不同反应活性的明确活性位点整合到一个催化剂单元中,预先设计的催化反应可以在相应的活化位点依次发生,即反应物在第一个位点被激活,产生的中间体将迁移到下一个位点,直至获得目标产物.串联反应不仅极大地降低了能量消耗的成本,而且根据勒夏特列原理,其可以显著影响热力学平衡,有效地将前一步的化学平衡前移,提高了催化转化效率,在减少分离步骤、控制反应顺序和选择性方面发挥着核心作用,有效地提高了工业工程工艺的可行性.本文全面系统地总结了核/蛋黄-壳串联纳米反应器的研究进展.介绍了该领域新颖的合成手段,包括原子层沉积法、脱硅-重结晶法和物理涂覆法等,明晰了核/蛋黄-壳结构的最佳生长条件,并对潜在的生长机理进行细致讨论,为精细整合串联催化剂活性组分分布提供新思路.另外,本文分别针对核壳反应器和蛋黄壳反应器,深入探讨了包括金属有机骨架、沸石、金属氧化物和碳材料在内的多种壳层材料对于多种串联催化反应的特殊作用,详细介绍了多相加氢、合成气转化、二氧化碳加氢、丙烷脱氢和纳米酶催化等串联反应的催化路径,并对结构-性能内禀关联进行了细致阐述,进而总结了核壳/蛋黄壳纳米反应器的适用范围.最后,概述了该领域面临的挑战和机遇,包括如何实现具有不同功能的催化中心在反应器内部的精准落位,如何精准调控壳层厚度、孔尺寸等精细结构以及如何实现多中心的合理兼容等.总之,核/蛋黄-壳串联纳米反应器在多相催化反应中表现出显著增强的催化性能,是一类极具发展前景的新催化体系.但相关研究仍处于起步阶段,仍需复出更大的努力实现结构的可控以及性能的优化. 展开更多
关键词 串联催化 核壳催化剂 蛋黄壳催化剂 纳米反应器 多相催化
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Premature deposition of lithium polysulfide in lithium-sulfur batteries 被引量:2
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作者 Zi-Xian Chen Yu-Tong Zhang +4 位作者 Chen-Xi Bi meng zhao Rui Zhang Bo-Quan Li Jia-Qi Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期507-512,I0011,共7页
Lithium-sulfur(Li-S)batteries have attracted extensive attention due to ultrahigh theoretical energy density of 2600 Wh kg^(-1).Liquid-solid deposition from dissolved lithium polysulfides(LiPSs)to solid lithium sulfid... Lithium-sulfur(Li-S)batteries have attracted extensive attention due to ultrahigh theoretical energy density of 2600 Wh kg^(-1).Liquid-solid deposition from dissolved lithium polysulfides(LiPSs)to solid lithium sulfide(Li_(2)S)largely determines the actual battery performances.Herein,a premature liquidsolid deposition process of LiPSs is revealed at higher thermodynamic potential than Li_(2)S deposition in Li-S batteries.The premature solid deposit exhibits higher chemical state and hemispherical morphology in comparison with Li_(2)S,and the premature deposition process is slower in kinetics and higher in deposition dimension.Accordingly,a supersaturation deposition mechanism is proposed to rationalize the above findings based on thermodynamic simulation.This work demonstrates a unique premature liquid-solid deposition process of Li-S batteries. 展开更多
关键词 Lithium-sulfur batteries Lithium polysulfides Liquid-solid deposition SUPERSATURATION
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Physical Activity,Sedentary Behavior,and the Risk of Cardiovascular Disease in Type 2 Diabetes Mellitus Patients:The MIDiab Study 被引量:1
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作者 Yafei Wu Guijun Qin +32 位作者 Guixia Wang Libin Liu Bing Chen Qingbo Guan Zhongshang Yuan Xu Hou Ling Gao Chao Xu Haiqing Zhang Xu Zhang Qiu Li Yongfeng Song Fei Jing Shizhan Ma Shanshan Shao meng zhao Qingling Guo Nanwei Tong Hongyan zhao Xiaomin Xie Chao Liu Zhongyan Shan Zhifeng Cheng Xuefeng Yu Shulin Chen Tao Yang Yangang Wang Dongmei Li zhaoli Yan Lixin Guo Qiuhe Ji Wenjuan Wang Jiajun zhao 《Engineering》 SCIE EI CAS CSCD 2023年第1期26-35,共10页
The aim of this study was to explore the associations of moderate-to-vigorous-intensity physical activity(MVPA)time and sedentary(SED)time with a history of cardiovascular disease(CVD)and multifactorial(i.e.,blood pre... The aim of this study was to explore the associations of moderate-to-vigorous-intensity physical activity(MVPA)time and sedentary(SED)time with a history of cardiovascular disease(CVD)and multifactorial(i.e.,blood pressure(BP),body mass index(BMI),low-density lipoprotein cholesterol(LDL-C),and glycated hemoglobin A1c(HbA1c))control status among type 2 diabetes mellitus(T2DM)patients in China.A cross-sectional analysis of 9152 people with type 2 diabetes from the Multifactorial Intervention on Type 2 Diabetes(MIDiab)study was performed.Patients were grouped according to their self-reported MVPA time(low,<150 min·week−1;moderate,150 to<450 min·week−1;high,≥450 min·week−1)and SED time(low,<4 h·d–1;moderate,4 to<8 h·d–1;high,≥8 h·d–1).Participants who self-reported a history of CVD were identified as having a CVD risk.Odds ratios(ORs)and 95%confidence intervals(CIs)of CVD risk and multifactorial control status associated with MVPA time and SED time were estimated using mixed-effect logistic regression models,adjusting for China’s geographical region characteristics.The participants had a mean±standard deviation(SD)age of(60.87±8.44)years,44.5%were women,and 25.1%had CVD.After adjustment for potential confounding factors,an inverse association between high MVPA time and CVD risk that was independent of SED time was found,whereas this association was not observed in the moderate-MVPA group.A higher MVPA time was more likely to have a positive effect on the control of BMI.Compared with the reference group(i.e.,those with MVPA time≥450 min·week−1 and SED time<4 h·d–1),CVD risk was higher in the low-MVPA group:The OR associated with an SED time<4 h·d–1 was 1.270(95%CI,1.040–1.553)and that associated with an SED time≥8 h·d–1 was 1.499(95%CI,1.149–1.955).We found that a high MVPA time(i.e.,≥450 min·week−1)was associated with lower odds of CVD risk regardless of SED time among patients with T2DM. 展开更多
关键词 Type 2 diabetes Physical activity Sedentary time Car diovascular disease
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Genomic prediction of yield performance among single-cross maize hybrids using a partial diallel cross design
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作者 Ping Luo Houwen Wang +23 位作者 Zhiyong Ni Ruisi Yang Fei Wang Hongjun Yong Lin Zhang Zhiqiang Zhou Wei Song Mingshun Li Jie Yang Jianfeng Weng zhaodong meng Degui Zhang Jienan Han Yong Chen Runze Zhang Liwei Wang meng zhao Wenwei Gao Xiaoyu Chen Wenjie Li Zhuanfang Hao Junjie Fu Xuecai Zhang Xinhai Li 《The Crop Journal》 SCIE CSCD 2023年第6期1884-1892,共9页
Genomic prediction(GP)in plant breeding has the potential to predict and identify the best-performing hybrids based on the genotypes of their parental lines.In a GP experiment,34 elite inbred lines were selected to ma... Genomic prediction(GP)in plant breeding has the potential to predict and identify the best-performing hybrids based on the genotypes of their parental lines.In a GP experiment,34 elite inbred lines were selected to make 285 single-cross hybrids in a partial-diallel cross design.These lines represented a mini-core collection of Chinese maize germplasm and comprised 18 inbred lines from the Stiff Stalk heterotic group and 16 inbred lines from the Non-Stiff Stalk heterotic group.The parents were genotyped by sequencing and the 285 hybrids were phenotyped for nine yield and yield-related traits at two locations in the summer sowing area(SUS)and three locations in the spring sowing area(SPS)in the main maizeproducing regions of China.Multiple GP models were employed to assess the accuracy of trait prediction in the hybrids.By ten-fold cross-validation,the prediction accuracies of yield performance of the hybrids estimated by the genomic best linear unbiased prediction(GBLUP)model in SUS and SPS were 0.51 and 0.46,respectively.The prediction accuracies of the remaining yield-related traits estimated with GBLUP ranged from 0.49 to 0.86 and from 0.53 to 0.89 in SUS and SPS,respectively.When additive,dominance,epistasis effects,genotype-by-environment interaction,and multi-trait effects were incorporated into the prediction model,the prediction accuracy of hybrid yield performance was improved.The ratio of training to testing population and size of training population optimal for yield prediction were determined.Multiple prediction models can improve prediction accuracy in hybrid breeding. 展开更多
关键词 MAIZE Genomic prediction Prediction model Genetic effects Hybrid performance
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The effects of hyperbaric oxygen therapy on paroxysmal sympathetic hyperactivity after cardiopulmonary resuscitation: a case series
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作者 Hongyu Wang Yihao Li +2 位作者 meng zhao Caihong Ren Sisen Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第6期477-480,共4页
The onset of cardiac arrest (CA) is sudden and critical.Due to cerebral ischaemia and hypoxia, the prognosis for post-cardiopulmonary resuscitation (CPR) patients is poor. Paroxysmal sympathetic hyperexcitability (PSH... The onset of cardiac arrest (CA) is sudden and critical.Due to cerebral ischaemia and hypoxia, the prognosis for post-cardiopulmonary resuscitation (CPR) patients is poor. Paroxysmal sympathetic hyperexcitability (PSH) is a potentially life-threatening condition, which is characterized by episodes of increased heart rate and blood pressure,sweating, hypothermia, and forced posture.[1] Hypoxicischaemic encephalopathy post-CPR can lead to PSH,which often indicates a worse prognosis. 展开更多
关键词 SYMPATHETIC RESUSCITATION PROGNOSIS
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浅析德惠市烤烟生产主要气象灾害及气象服务
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作者 赵明 孟钊 +2 位作者 计成豪 叶梦龙 张奇 《南方农业》 2023年第6期221-223,共3页
烤烟种植是吉林省德惠市重要的经济产业,低温寒潮、暴雨、干旱、大风、冰雹等灾害性天气对德惠市烤烟生产影响较大,因此加强烤烟生产气象服务十分必要。为充分发挥烤烟生产气象服务优势,全力保障烤烟增产增收,简要总结德惠市烤烟生长期... 烤烟种植是吉林省德惠市重要的经济产业,低温寒潮、暴雨、干旱、大风、冰雹等灾害性天气对德惠市烤烟生产影响较大,因此加强烤烟生产气象服务十分必要。为充分发挥烤烟生产气象服务优势,全力保障烤烟增产增收,简要总结德惠市烤烟生长期主要的气象灾害及其影响,从开展烤烟生长期专业气象跟踪服务、确保气象预测信息发布渠道畅通、联合烟叶公司指导烤烟生产及加强组织实施人影天气作业等方面介绍德惠市烤烟生产气象服务措施,并提出了加强烤烟生产气象服务的路径。 展开更多
关键词 烤烟生产 气象灾害 气象服务 吉林省德惠市
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石膏矫形治疗幼儿特发性脊柱侧弯的临床研究 被引量:3
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作者 郭旭朝 孟钊 +6 位作者 王飞 王晨 邢乾一 邹岩 赵硕 朱华 刘俊行 《临床小儿外科杂志》 CAS 2020年第2期130-134,共5页
目的介绍简易石膏床方法行石膏矫形治疗幼儿特发性脊柱侧弯,并进行效果评价。方法选取2014年9月至2016年9月于河北省儿童医院住院治疗的25例幼儿特发性脊柱侧弯病例作为研究对象,平均年龄29.7个月(17~53个月),其中男童10例,女童15例,共... 目的介绍简易石膏床方法行石膏矫形治疗幼儿特发性脊柱侧弯,并进行效果评价。方法选取2014年9月至2016年9月于河北省儿童医院住院治疗的25例幼儿特发性脊柱侧弯病例作为研究对象,平均年龄29.7个月(17~53个月),其中男童10例,女童15例,共行石膏矫形105次。应用去旋转石膏矫形方法并结合我院实际情况采用简易石膏床对患儿进行石膏矫形,测量并记录石膏矫形前后脊柱正位X线片上Cobb角改变情况,并对所有患儿按照性别及年龄是否≤2岁进行分组分析。结果 25例患儿石膏矫形治疗前脊柱侧弯Cobb角平均角度为(39.1±9.1)°,经过第1次石膏矫形后平均角度为(22.3±5.0)°,末次随访时平均角度为(20.3±4.3)°。第1次石膏矫形后Cobb角与矫形前相比差异有统计学意义(t=8.825,P<0.05)。随访终点时Cobb角与矫形前相比差异有统计学意义(t=9.653,P<0.05)。不同性别分组随访终点时Cobb角矫正度数差异无统计学意义(t=0.070,P=0.945)。不同年龄分组随访终点时Cobb角矫正度数差异无统计学意义(t=-0.733,P=0.471)。结论我们采用的简易石膏床方法结合去旋转技术进行石膏矫形可以纠正幼儿特发性脊柱侧弯患儿的Cobb角,性别和年龄因素未对矫正效果产生影响。 展开更多
关键词 特发性脊柱侧弯 幼儿 石膏 非手术治疗
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基于CT影像的儿童先天性脊柱侧凸胸椎椎弓根螺钉置钉精确性评价 被引量:2
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作者 郭旭朝 孟钊 +5 位作者 王晨 朱华 赵硕 王飞 邹岩 刘俊行 《脊柱外科杂志》 2022年第5期307-312,共6页
目的通过CT评价10岁以下先天性脊柱侧凸儿童徒手置入胸椎椎弓根螺钉的精确性。方法回顾性分析2014年12月—2018年12月收治的26例先天性脊柱侧凸患儿临床资料。所有患儿均为单胸弯或胸腰弯,术中依据胸椎解剖标志结合C形臂X线机定位进行... 目的通过CT评价10岁以下先天性脊柱侧凸儿童徒手置入胸椎椎弓根螺钉的精确性。方法回顾性分析2014年12月—2018年12月收治的26例先天性脊柱侧凸患儿临床资料。所有患儿均为单胸弯或胸腰弯,术中依据胸椎解剖标志结合C形臂X线机定位进行徒手置钉。术后在CT上测量螺钉穿破椎体(包括椎弓根)骨皮质内侧、外侧或前侧的距离,<2 mm为准确置钉,≥2 mm为异常置钉。同时记录术中或术后是否发生置钉相关并发症。结果胸椎区共置入椎弓根螺钉165枚,每例患儿置入6.3±1.8枚螺钉。准确置钉129枚(78.2%),异常置钉36枚(21.8%)。形态异常椎异常置钉率(41.8%,23/55)高于正常椎(11.8%,13/110),且形态异常椎凹侧异常置钉率(77.8%,14/18)高于凸侧(24.3%,9/37);顶椎区异常置钉率(35.0%,21/60)高于非顶椎区(14.3%,15/105),且顶椎区凹侧异常置钉率(50.0%,12/24)高于凸侧(25.0%,9/36);差异均有统计学意义(P<0.05)。术中及术后未发生置钉相关并发症。结论对10岁以下先天性脊柱侧凸儿童进行胸椎徒手置钉具有较高的精确性,术后很少发生置钉相关并发症。形态异常椎体、顶椎区置钉时需谨慎操作,尤其是这两个区域的凹侧置钉时要慎之又慎。 展开更多
关键词 儿童 胸椎 脊柱侧凸 骨钉
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盆腔炎性疾病后遗症病机探讨 被引量:5
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作者 詹新林 肖英 +1 位作者 孟钊 宋悦 《中国中医药现代远程教育》 2022年第4期74-76,共3页
盆腔炎性疾病后遗症乃本虚标实之证,多为虚实夹杂,尤以气血亏虚为本,气机郁结、血瘀、湿浊为标,因此治疗盆腔炎性疾病后遗症,常常从虚、郁、瘀、湿入手,以益气养血、调理气机、活血化瘀、温阳升清祛湿等为治法治则,扶助正气的同时,兼顾... 盆腔炎性疾病后遗症乃本虚标实之证,多为虚实夹杂,尤以气血亏虚为本,气机郁结、血瘀、湿浊为标,因此治疗盆腔炎性疾病后遗症,常常从虚、郁、瘀、湿入手,以益气养血、调理气机、活血化瘀、温阳升清祛湿等为治法治则,扶助正气的同时,兼顾祛除邪气,多法联用,随证治之。 展开更多
关键词 盆腔炎性疾病后遗症 病机 湿
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水平井岩屑床清洁工具的设计与试验 被引量:10
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作者 纪国栋 汪海阁 +3 位作者 黄洪春 孟昭 崔柳 郭卫红 《天然气工业》 EI CAS CSCD 北大核心 2021年第2期125-131,共7页
页岩气井水平段钻进过程中的岩屑堆积是造成钻井摩阻扭矩大、托压严重进而影响钻井速度的主要原因之一,因而抑制岩屑床生成、保持井眼清洁是确保水平段安全顺利钻进的重要前提。为了提高水平井段井眼清洁的效率,应用CFD数值模拟方法、... 页岩气井水平段钻进过程中的岩屑堆积是造成钻井摩阻扭矩大、托压严重进而影响钻井速度的主要原因之一,因而抑制岩屑床生成、保持井眼清洁是确保水平段安全顺利钻进的重要前提。为了提高水平井段井眼清洁的效率,应用CFD数值模拟方法、采用欧拉—欧拉双流体模型并结合颗粒动力学理论,对所研发的带有“V”形叶片的新型水平井岩屑床清洁工具的螺旋角、转速参数诱导螺旋流动衰减规律及对岩屑颗粒重新悬浮分布的影响等进行了研究,进而优选了叶片旋转速度、叶片螺旋角等关键参数。研究结果表明:①随着转速的增加,环空底部的岩屑沉积发生了一定程度的偏转,转速越大偏转越明显;②环空压降损失随着螺旋角的增加而增大,在螺旋角较大时该现象表现更为明显;③在四川盆地南部地区长宁H25-7井进行的现场试验结果表明,使用新型水平井岩屑床清洁工具后钻进摩阻下降33%,起下钻通畅、无阻卡,新工具应用过程中未发生井下复杂事故,发挥了良好的井眼清洁作用,保证了后期下套管作业的安全顺利实施。结论认为,该工具不仅可以满足水平井岩屑床的清洗及钻井降本增效的需求,具有良好的推广应用价值,而且还可以为同类型岩屑床清洁工具的设计提供借鉴与参考。 展开更多
关键词 页岩气 水平井 井眼清洁 “V”形叶片 岩屑床清洁工具 反螺旋叶片 CFD
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极端天气陆地河流面源污染对珠江河口叶绿素分布的影响——评价方法构建与应用 被引量:1
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作者 黄靖雯 孟钊 +5 位作者 冯青郁 马伟伟 万修全 周巍 李佳俊 冯洋 《生态学报》 CAS CSCD 北大核心 2022年第5期1911-1923,共13页
近十年来,随着我国粤港澳大湾区的建设,珠江流域人口增长十分迅速,食品和能源需求急剧增加,导致流域上游省份农业用地面积增加,下游省份城市化进程加速,随之导致含农业化肥的农田灌溉用水和生活污水排放大幅度增加。流域的面源污染物进... 近十年来,随着我国粤港澳大湾区的建设,珠江流域人口增长十分迅速,食品和能源需求急剧增加,导致流域上游省份农业用地面积增加,下游省份城市化进程加速,随之导致含农业化肥的农田灌溉用水和生活污水排放大幅度增加。流域的面源污染物进入珠江河口,导致河口海域赤潮发生频率明显增高。此外,全球变暖加剧了南海和西太台风等极端天气事件的发生频率,大量的台风在珠江口附近登陆,对人类活动产生的营养盐在海水中再分布产生较大影响。现场及卫星观测表明,台风等极端天气影响浮游植物时空分布的4个主要影响因子为:海水的垂直混合、流域的降水增加、河流淡水及营养盐的大量输入及风场变化。但是,尚未对这些因子如何影响叶绿素分布进行过清晰阐释。研究构建了粤港澳大湾区陆海气集成模拟系统,一方面通过控制实验来对模式敏感性进行测试,另一方面以台风“天鸽”过境珠江口为例,来对台风过境期间海表叶绿素时空变化机理进行探究。结果表明,陆地模式径流分辨率的提高对模拟结果有很大影响,台风“天鸽”过境时,向岸的风抑制了珠江冲淡水排出,促进外海水涌入,提高海表盐度,降低叶绿素浓度。而台风所致的陆地降水在过境后四天(8月27日)通过径流输出至河口,此次剧烈的增水向珠江口输入大量的营养盐,促进浮游植物持续生长,使叶绿素浓度在台风过境两周(9月1日)后仍在增加。研究所构建的集成模拟系统可适于其它受河口面源污染影响的海湾及近海系统。为未来实现赤潮、缺氧等生态灾害预报提供可能性。 展开更多
关键词 珠江口 陆海气集成模式 台风“天鸽” 海表叶绿素浓度
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Efficacy and safety of nerve growth factor for the treatment of neurological diseases:a meta-analysis of 64 randomized controlled trials involving 6,297 patients 被引量:12
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作者 meng zhao Xiao-yan Li +1 位作者 Chun-ying Xu Li-ping Zou 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第5期819-828,共10页
OBJECTIVE: China is the only country where nerve growth factor is approved for large-scale use as a clinical medicine. More than 10 years ago, in 2003, nerve growth factor injection was listed as a national drug. The... OBJECTIVE: China is the only country where nerve growth factor is approved for large-scale use as a clinical medicine. More than 10 years ago, in 2003, nerve growth factor injection was listed as a national drug. The goal of this article is to evaluate comprehensively the efficacy and safety of nerve growth factor for the treatment of neurological diseases. DATA RETRIEVAL: A computer-based retrieval was performed from six databases, including the Cochrane Library, PubMed, EMBASE, Sino Med, CNKI, and the VIP database, searching from the clinical establishment of nerve growth factor for treatment until December 31, 2013. The key words for the searches were "nerve growth factor, randomized controlled trials" in Chinese and in English. DATA SELECTION: Inclusion criteria: any study published in English or Chinese referring to randomized controlled trials of nerve growth factor; patients with neurological diseases such as peripheral nerve injury, central nerve injury, cranial neuropathy, and nervous system infections; patients older than 7 years; similar research methods and outcomes assessing symptoms; and measurement of nerve conduction velocities. The meta-analysis was conducted using Review Manager 5.2.3 software. MAIN OUTCOME MEASURES: The total effective rate, the incidence of adverse effects, and the nerve conduction velocity were recorded for each study. RESULTS: Sixty-four studies involving 6,297 patients with neurological diseases were included. The total effective rate in the group treated with nerve growth factor was significantly higher than that in the control group (P 〈 0.0001, RR: 1.35, 95%CI: 1.30-1.40). The average nerve conduction velocity in the nerve growth factor group was significantly higher than that in the control group (P 〈 0.00001, MD. 4.59 m/s, 95%CI: 4.12-5.06). The incidence of pain or sclero- ma at the injection site in the nerve growth factor group was also higher than that in the control group (P 〈 0.00001, RR: 6.30, 95%CI: 3.53-11.27), but such adverse effects were mild. CONCLUSION: Nerve growth factor can significantly improve nerve function in patients with nervous system disease and is safe and effective. 展开更多
关键词 nerve regeneration neurological diseases nerve growth factor randomized controlledtrials META-ANALYSIS adverse effects nerve conduction velocity neural regeneration
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Mechanisms and therapeutic advances in the management of endocrine-resistant breast cancer 被引量:17
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作者 meng zhao Bhuvaneswari Ramaswamy 《World Journal of Clinical Oncology》 CAS 2014年第3期248-262,共15页
The estrogen receptor(ER) pathway plays a critical role in breast cancer development and progression. Endocrine therapy targeting estrogen action is the most important systemic therapy for ER positive breast cancer. H... The estrogen receptor(ER) pathway plays a critical role in breast cancer development and progression. Endocrine therapy targeting estrogen action is the most important systemic therapy for ER positive breast cancer. However its efficacy is limited by intrinsic and acquired resistance. Mechanisms responsible for endocrine resistance include deregulation of the ER pathway itself, including loss of ER expression, posttranslational modification of ER, deregulation of ER coactivators; increased receptor tyrosine kinase signaling leading to activation of various intracellular pathways involved in signal transduction, proliferation and cell survival, including growth factor receptor tyrosine kinases human epidermal growth factor receptor-2, epidermal growth factor receptor, PI3K/AKT/mammalian target of rapamycin(m TOR), Mitogen activated kinase(MAPK)/ERK, fibroblast growth factor receptor, insulin-like growth factor-1 receptor; alterations in cell cycle and apoptotic machinery; Epigenetic modificationincluding dysregulation of DNA methylation, histone modification, and nucleosome remodeling; and altered expression of specific micro RNAs. Functional genomics has helped us identify a catalog of genetic and epigenetic alterations that may be exploited as potential therapeutic targets and biomarkers of response. New treatment combinations targeting ER and such oncogenic signaling pathways which block the crosstalk between these pathways have been proven effective in preclinical models. Results of recent clinical studies suggest that subsets of patients benefit from the combination of inhibitor targeting certain oncogenic signaling pathway with endocrine therapy. Especially, inhibition of the m TOR signaling pathway, a key component implicated in mediating multiple signaling cascades, offers a promising approach to restore sensitivity to endocrine therapy in breast cancer. We systematically reviewed important publications cited in Pub Med, recent abstracts from ASCO annual meetings and San Antonio Breast Cancer Symposium, and relevant trials registered at Clinical Trials.gov. We present the molecular mechanisms contributing to endocrine resistance, in particular focusing on the biological rationale for the clinical development of novel targeted agents in endocrine resistant breast cancer. We summarize clinical trials utilizing novel strategies to overcome therapeutic resistance, highlighting the need to better identify the appropriate patients whose diseases are most likely to benefit from these specific strategies. 展开更多
关键词 ENDOCRINE THERAPY ENDOCRINE resistance Breast cancer THERAPEUTIC ADVANCES Targeted THERAPY
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联合分层注意力网络和独立循环神经网络的地域欺凌识别
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作者 孟曌 田生伟 +1 位作者 禹龙 王瑞锦 《计算机应用》 CSCD 北大核心 2019年第8期2450-2455,共6页
为提高对文本语境深层次信息的利用效率,提出了联合分层注意力网络(HAN)和独立循环神经网络(IndRNN)的地域欺凌文本识别模型——HACBI。首先,将手工标注的地域欺凌文本通过词嵌入技术映射到低维向量空间中;其次,借助卷积神经网络(CNN)... 为提高对文本语境深层次信息的利用效率,提出了联合分层注意力网络(HAN)和独立循环神经网络(IndRNN)的地域欺凌文本识别模型——HACBI。首先,将手工标注的地域欺凌文本通过词嵌入技术映射到低维向量空间中;其次,借助卷积神经网络(CNN)和双向长短期记忆网络(BiLSTM)提取地域欺凌文本的局部及全局语义特征,并进一步利用HAN捕获文本的内部结构信息;最后,为避免文本层次结构信息丢失和解决梯度消失等问题,引入IndRNN以增强模型的描述能力,并实现信息流的整合。实验结果表明,该模型的准确率(Acc)、精确率(P)、召回率(R)、F1和AUC值分别为99.57%、98.54%、99.02%、98.78%和99.35%,相比支持向量机(SVM)、CNN等文本分类模型有显著提升。 展开更多
关键词 地域欺凌 结构信息 分层注意力网络 独立循环神经网络 词向量 语境
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