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经桡动脉入路颅内动脉狭窄支架成形术四例
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作者 史美燕 张贤军 +2 位作者 王宪伟 张勇 王乃东 《中国现代神经疾病杂志》 CAS 北大核心 2024年第5期382-390,共9页
目的 报道4例经桡动脉入路行颅内动脉狭窄支架成形术的缺血性卒中病例并总结其治疗经验。方法与结果 回顾分析2022年青岛大学附属医院采用经桡动脉入路行颅内动脉狭窄支架成形术的4例缺血性卒中患者的诊断与治疗过程,狭窄分别位于左颈... 目的 报道4例经桡动脉入路行颅内动脉狭窄支架成形术的缺血性卒中病例并总结其治疗经验。方法与结果 回顾分析2022年青岛大学附属医院采用经桡动脉入路行颅内动脉狭窄支架成形术的4例缺血性卒中患者的诊断与治疗过程,狭窄分别位于左颈内动脉起始部、右椎动脉起始部、左椎动脉V4段、左椎动脉V4段与基底动脉起始部交界处,经桡动脉入路颅内动脉狭窄支架成形术顺利,术后狭窄均再通,术中及术后无一例出现并发症。结论 经桡动脉入路颅内动脉狭窄支架成形术治疗缺血性卒中安全、有效。 展开更多
关键词 缺血性卒中 桡动脉 脑动脉 血管成形术 支架
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二氢杨梅素对运动性骨骼肌损伤的保护作用及机制研究
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作者 吴瑛 王大伟 +5 位作者 李军 许贤杰 高志丹 李鸿雁 张勇 刘鹏 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第1期46-53,I0005,共9页
目的探讨二氢杨梅素(dihydromyricetin,DHM)对运动训练后小鼠骨骼肌损伤的保护作用及潜在机制。方法将成年雄性C57BL/6J小鼠随机分为安静对照组(CG)、运动组(EG)、二氢杨梅素(100mg/kg·d)+运动组(DHM组)。干预期4周,同时进行运动训... 目的探讨二氢杨梅素(dihydromyricetin,DHM)对运动训练后小鼠骨骼肌损伤的保护作用及潜在机制。方法将成年雄性C57BL/6J小鼠随机分为安静对照组(CG)、运动组(EG)、二氢杨梅素(100mg/kg·d)+运动组(DHM组)。干预期4周,同时进行运动训练,每天1小时。训练结束后的次日,EG组和DHM组进行一次坡度为0、速度为18 m/min、持续90 min的跑台运动。运动结束后24小时按组别取材,测定血清肌酸激酶(creatine kinase,CK)、乳酸脱氢酶(lactate dehydrogenase,LDH)和总超氧化物歧化酶(total superoxide dismutase,T-SOD)活性、丙二醛(malondialdehyde,MDA)含量和骨骼肌线粒体酶复合体Ⅰ和Ⅱ的活性,观察骨骼肌病理学组织形态变化。免疫印迹法(Western blot)检测线粒体功能相关通路的蛋白表达。结果与EG组相比,DHM组小鼠骨骼肌形态改变和线粒体损伤明显减轻。DHM显著抑制了运动后骨骼肌损伤的标志物CK和LDH及脂质过氧化水平,提高了骨骼肌T-SOD活性。Western blot结果显示,DHM显著增加小鼠骨骼肌沉默调节蛋白3(SIRT3)、雌激素相关受体α(EERα)和过氧化物酶体增殖物激活受体-γ共激活因子-1α(peroxisome proliferator-activated receptor gamma coactivator-1 alpha,PGC-1α)的表达。结论DHM有助于减轻小鼠运动性骨骼肌损伤,其机制可能是DHM可激活肌肉SIRT3信号通路,促进大强度运动后骨骼肌线粒体结构和功能的恢复。 展开更多
关键词 二氢杨梅素 运动性骨骼肌损伤 线粒体功能
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Relationship between the unique microstructures and behaviors of high-entropy alloys 被引量:2
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作者 Yaqi Wu Peter KLiaw +5 位作者 Ruixuan Li Weiran zhang Guihong Geng Xuehui Yan Guiqun Liu yong zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1350-1363,共14页
High-entropy alloys(HEAs),which were introduced as a pioneering concept in 2004,have captured the keen interest of nu-merous researchers.Entropy,in this context,can be perceived as representing disorder and randomness... High-entropy alloys(HEAs),which were introduced as a pioneering concept in 2004,have captured the keen interest of nu-merous researchers.Entropy,in this context,can be perceived as representing disorder and randomness.By contrast,elemental composi-tions within alloy systems occupy specific structural sites in space,a concept referred to as structure.In accordance with Shannon entropy,structure is analogous to information.Generally,the arrangement of atoms within a material,termed its structure,plays a pivotal role in dictating its properties.In addition to expanding the array of options for alloy composites,HEAs afford ample opportunities for diverse structural designs.The profound influence of distinct structural features on the exceptional behaviors of alloys is underscored by numer-ous examples.These features include remarkably high fracture strength with excellent ductility,antiballistic capability,exceptional radi-ation resistance,and corrosion resistance.In this paper,we delve into various unique material structures and properties while elucidating the intricate relationship between structure and performance. 展开更多
关键词 high-entropy alloys unique microstructure special properties alloy design
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进口导叶对斜流式叶轮级性能调节的数值研究
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作者 于家懿 张勇 +3 位作者 李廷宾 闻苏平 席光 祁志刚 《风机技术》 2024年第2期8-16,共9页
针对两种不同翼型的进口导叶,数值研究了导叶在不同开度下对超大流量系数斜流级内部气体流动的影响和调节特性,并预测了进口导叶与斜流叶轮耦合在不同导叶开度下的性能曲线。结果表明,进口导叶能有效扩大调节范围,使斜流压缩机能在更宽... 针对两种不同翼型的进口导叶,数值研究了导叶在不同开度下对超大流量系数斜流级内部气体流动的影响和调节特性,并预测了进口导叶与斜流叶轮耦合在不同导叶开度下的性能曲线。结果表明,进口导叶能有效扩大调节范围,使斜流压缩机能在更宽的工况范围内运行。导叶开度和翼型对斜流叶轮的气动性能产生影响,开度增大导致气体流动的不均匀性变大,而当开度增大到一定程度时,进口导叶的调节能力变差,对斜流叶轮气动性能产生负面影响。 展开更多
关键词 可调进口导叶 数值模拟 斜流级 数值研究 斜流叶轮
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气流染色机用离心通风机的优化设计
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作者 吕晓峰 张勇 +3 位作者 闻苏平 王志恒 国成 于家懿 《风机技术》 2024年第1期30-37,共8页
离心通风机是气流染色系统的核心部件,其性能优劣直接决定气流染色系统的染色质量和能耗水平。本文针对某气流染色机用离心通风机的气动性能和几何结构开展优化设计,以风机全压PtF和全压效率ηtF最大化为优化目标,利用基于人工神经网络... 离心通风机是气流染色系统的核心部件,其性能优劣直接决定气流染色系统的染色质量和能耗水平。本文针对某气流染色机用离心通风机的气动性能和几何结构开展优化设计,以风机全压PtF和全压效率ηtF最大化为优化目标,利用基于人工神经网络构建的代理模型,结合带精英策略的遗传算法对离心通风机叶轮开展优化设计,同时基于叶轮与蜗壳耦合整机气动匹配条件下对蜗壳几何结构进行优化设计。试验结果表明,优化设计的离心通风机结构更紧凑,其全压PtF提升约500Pa,其全压效率ηtF提升约5%。 展开更多
关键词 离心通风机 优化设计 性能试验
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空心球状共价有机框架负载金纳米粒子用于光催化生产过氧化氢
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作者 张勇 邱俊逸 +3 位作者 朱必成 孙国太 程蓓 王临曦 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期143-153,共11页
过氧化氢是一种高效的绿色氧化剂,广泛应用于纸浆漂白、外科消毒、废水处理和化学合成等领域.目前,过氧化氢的工业生产仍依赖于传统的蒽醌氧化法,该方法存在能耗高、污染大以及工艺复杂等问题.以太阳能为驱动力,水和氧气作为原料,利用... 过氧化氢是一种高效的绿色氧化剂,广泛应用于纸浆漂白、外科消毒、废水处理和化学合成等领域.目前,过氧化氢的工业生产仍依赖于传统的蒽醌氧化法,该方法存在能耗高、污染大以及工艺复杂等问题.以太阳能为驱动力,水和氧气作为原料,利用半导体材料光催化生产过氧化氢被认为是一种清洁、安全、经济和节能的技术.该技术的关键是开发高效稳定的半导体光催化材料.共价有机框架(COF)是一种可用于光催化产过氧化氢的新型晶态多孔有机材料,具有结构可调控、密度低、比表面积大、热稳定性和化学稳定性高等优点,但其应用受到光生载流子快速复合的限制.将助催化剂金纳米粒子负载在COF表面,可以有效促进光生载流子的迁移与分离,从而获得较好的光催化产双氧水性能.然而,这方面的研究尚未受到较多的关注.本文采用NaBH_(4)还原法将金纳米粒子原位负载在一种空心球状COF(TB-COF)的表面,制得了不同Au含量的Au/TB-COF复合物(记为AT-x,其中x代表复合物中Au的质量百分含量),并系统研究了该材料光催化生产过氧化氢的性能.粉末X射线衍射(XRD)、透射电子显微镜(TEM)和傅里叶转换红外光谱(FT-IR)等表征结果证明了Au/TB-COF复合物的成功制备,且发现原位负载的金纳米粒子并没有改变TB-COF的晶型、形貌和化学结构.在光催化反应中,以乙醇作为牺牲剂时,复合物AT-1的性能最佳,表现出最高的过氧化氢生成速率常数(Kf)和最低的过氧化氢分解速率常数(Kd),在可见光照射下过氧化氢生成速率达到6067μmol g^(-1)h^(-1),超过大多文献报道的COF基光催化剂性能.经4次光催化循环反应后,AT-1催化生成过氧化氢的产率略有下降,且FTIR谱、XRD谱和FESEM显示光催化反应前后AT-1的结构和形态几乎没有变化,表明其具有较好的光催化稳定性.此外,在本实验所制得的AT-x复合物中,AT-1具有最短的荧光平均寿命、最大的光电流响应和最小的阻抗,表明其具有最高的光生载流子迁移和分离能力.原位辐照X射线光电子能谱结果表明,界面电子在光照前后均从TB-COF转移到金纳米粒子,与密度泛函理论计算结果一致.电子顺磁共振和原位漫反射傅里叶变换红外光谱等实验证实了光催化过程中超氧自由基的存在,这表明AT-1光催化生产过氧化氢是连续两步单电子氧气还原的过程.实验还发现,当O_(2)被N_(2)替代时,几乎检测不到过氧化氢的产生,说明过氧化氢来源于O_(2)的还原反应.当用硝酸银和对苯醌分别作为捕获剂来消除·O_(2)^(−)和e^(−)时,光催化过氧化氢的产率显著下降,可推断·O_(2)^(−)和e^(−)是产生过氧化氢的关键物种.综上,本文详细研究了金纳米粒子作为助催化剂对COF光催化生成过氧化氢性能的促进作用,可为设计高效光催化生成过氧化氢的COF基催化剂提供参考.目前,光催化生产过氧化氢技术仍处于起步阶段,其产率仍处于mmol g^(-1)h^(-1)的水平,尚不能达到工业生产要求.开发高效的半导体催化剂是实现高效光催化生产过氧化氢的关键.未来还需要进一步提高光催化产过氧化氢的生成效率和选择性,解决O_(2)的有效吸附、可见光有效利用、光生载流子的分离与转移效率等问题,以推进光催化产过氧化氢技术的工业生产和商业应用. 展开更多
关键词 共价有机框架 金纳米粒子 光催化 双氧水生产 氧气还原
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The Jiao Tong University Spectroscopic Telescope Project 被引量:1
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作者 JUST Team Chengze Liu +28 位作者 Ying Zu Fabo Feng Zhaoyu Li Yu Yu Hua Bai Xiangqun Cui Bozhong Gu Yizhou Gu Jiaxin Han yonghui Hou Zhongwen Hu Hangxin Ji Yipeng Jing Wei Li Zhaoxiang Qi Xianyu Tan Cairang Tian Dehua Yang Xiangyan Yuan Chao Zhai Congcong zhang Jun zhang Haotong zhang Pengjie zhang yong zhang Yi Zhao Xianzhong Zheng Qingfeng Zhu Xiaohu Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期16-30,共15页
The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a di... The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 m.JUST provides two Nasmyth platforms for placing science instruments.One Nasmyth focus fits a field of view of 10′and the other has an extended field of view of 1.2°with correction optics.A tertiary mirror is used to switch between the two Nasmyth foci.JUST will be installed at a site at Lenghu in Qinghai Province,China,and will conduct spectroscopic observations with three types of instruments to explore the dark universe,trace the dynamic universe,and search for exoplanets:(1)a multi-fiber(2000 fibers)medium-resolution spectrometer(R=4000-5000)to spectroscopically map galaxies and large-scale structure;(2)an integral field unit(IFU)array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy;(3)a high-resolution spectrometer(R~100000)designed to identify Jupiter analogs and Earth-like planets,with the capability to characterize the atmospheres of hot exoplanets. 展开更多
关键词 Astronomical instrumentation Optical telescopes Large-scale structure of the universe Redshift surveys Time domain astronomy Exoplanet astronomy
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Geochemistry, zircon U–Pb geochronology, and Hf isotopes of S-type granite in the Baoshan block, constraints on the age and evolution of the Proto-Tethys
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作者 Jianjun zhang Chuanlong Mou +3 位作者 Chendong Liu yong zhang Ting Chen Hualiang Li 《Acta Geochimica》 EI CAS CSCD 2024年第1期40-58,共19页
Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkali... Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge. 展开更多
关键词 Baoshan block Early Paleozoic GRANITE GEOCHEMISTRY ZIRCON GEOCHRONOLOGY Hf isotope
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Effect of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy
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作者 Xian-wen YANG Ling-ying YE +1 位作者 yong zhang Quan-shi CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2415-2430,共16页
The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties... The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties,local corrosion properties,and slow strain rate tensile stress corrosion tests.Microstructure characterization techniques such as metallographic microscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were also employed.The results indicate that the tensile strength of the alloy produced by T6I6 aging is similar to that produced by T6I4 aging,and it even exceeds 700 MPa.Furthermore,the yield strength increases by 52.7 MPa,reaching 654.8 MPa after T6I6 aging treatment.The maximum depths of intergranular corrosion(IGC)and exfoliation corrosion(EXCO)decrease from 116.3 and 468.5μm to 89.5 and 324.3μm,respectively.The stress corrosion factor also decreases from 2.1%to 1.6%.These findings suggest that the alloy treated with T6I6 aging exhibits both high strength and excellent stress corrosion cracking resistance.Similarly,when the alloy is treated with T6I4,T6I6 and T6I7 aging,the sizes of grain boundary precipitates(GBPs)are found to be 5.2,18.4,and 32.8 nm,respectively.The sizes of matrix precipitates are 4.8,5.7 and 15.7 nm,respectively.The atomic fractions of Zn in GBPs are 9.92 at.%,8.23 at.%and 6.87 at.%,respectively,while the atomic fractions of Mg are 12.66 at.%,8.43 at.%and 7.00 at.%,respectively.Additionally,the atomic fractions of Cu are 1.83 at.%,2.47 at.%and 3.41 at.%,respectively. 展开更多
关键词 7A75 aluminum alloy interrupted aging aging precipitation behavior mechanical properties intergranular corrosion exfoliation corrosion stress corrosion cracking
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Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling
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作者 Bei Li yong zhang +9 位作者 Xinyuan Liu Ziyang zhang Shuqing Zhuang Xiaoli Zhong Wenbo Chen Yilin Hong Pingli Mo Shuhai Lin Shicong Wang Chundong Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期601-614,共14页
Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we re... Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis. 展开更多
关键词 Pien Tze Huang Bile acids SEPSIS Inflammation TGR5 STAT3-A20 signalling
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Regional Climate Damage Quantification and Its Impacts on Future Emission Pathways Using the RICE Model
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作者 Shili YANG Wenjie DONG +2 位作者 Jieming CHOU yong zhang Weixing ZHAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1843-1852,共10页
This study quantified the regional damages resulting from temperature and sea level changes using the Regional Integrated of Climate and Economy(RICE)model,as well as the effects of enabling and disabling the climate ... This study quantified the regional damages resulting from temperature and sea level changes using the Regional Integrated of Climate and Economy(RICE)model,as well as the effects of enabling and disabling the climate impact module on future emission pathways.Results highlight varied damages depending on regional economic development and locations.Specifically,China and Africa could suffer the most serious comprehensive damages caused by temperature change and sea level rise,followed by India,other developing Asian countries(OthAsia),and other high-income countries(OHI).The comprehensive damage fractions for China and Africa are projected to be 15.1%and 12.5%of gross domestic product(GDP)in 2195,with corresponding cumulative damages of 124.0 trillion and 87.3 trillion United States dollars(USD)from 2005 to 2195,respectively.Meanwhile,the comprehensive damage fractions in Japan,Eurasia,and Russia are smaller and projected to be lower than 5.6%of GDP in 2195,with cumulative damages of 6.8 trillion,4.2 trillion,and 3.3 trillion USD,respectively.Additionally,coastal regions like Africa,the European Union(EU),and OHI show comparable damages for sea level rise and temperature change.In China,however,sea level-induced damages are projected to exceed those from temperature changes.Moreover,this study indicates that switching the damage modules on or off affects the regional and global emission trajectories,but the magnitude is relatively small.By 2195,global emissions under the experiments with all of the damage modules switched off,only the sea level damage module switched on,and only the temperature damage module switched on,were 3.5%,2.3%and 1.2%higher than those with all of the damage modules switched on,respectively. 展开更多
关键词 climate damage integrated assessment model carbon emissions sea level rise temperature change
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Linear magnetoresistance and structural distortion in layered SrCu_(4-x)P_(2) single crystals
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作者 聂勇 陈正 +10 位作者 韦文森 李慧杰 张勇 梅明 王园园 宋文海 宋东升 王钊胜 朱相德 宁伟 田明亮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期591-594,共4页
We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magne... We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion. 展开更多
关键词 linear magnetoresistance thermal expansion specific heat structural distortion
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Spatially resolved transcriptomic profiling of placental development in dairy cow
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作者 Guang-Hui Tan Shi-Jie Liu +11 位作者 Ming-Le Dou De-Feng Zhao Ao zhang Heng-Kuan Li Fu-Nong Luo Tao Shi Hao-Ping Wang Jing-Yuan Lei yong zhang Yu Jiang Yi Zheng Fei Wang 《Zoological Research》 SCIE CSCD 2024年第3期586-600,共15页
The placenta plays a crucial role in successful mammalian reproduction.Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fe... The placenta plays a crucial role in successful mammalian reproduction.Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fetal placental cotyledons,essential for full-term fetal development.The cow placenta harbors at least two trophoblast cell populations:uninucleate(UNC)and binucleate(BNC)cells.However,the limited capacity to elucidate the transcriptomic dynamics of the placental natural environment has resulted in a poor understanding of both the molecular and cellular interactions between trophoblast cells and niches,and the molecular mechanisms governing trophoblast differentiation and functionalization.To fill this knowledge gap,we employed Stereo-seq to map spatial gene expression patterns at near single-cell resolution in the cow placenta at 90 and 130 days of gestation,attaining high-resolution,spatially resolved gene expression profiles.Based on clustering and cell marker gene expression analyses,key transcription factors,including YBX1 and NPAS2,were shown to regulate the heterogeneity of trophoblast cell subpopulations.Cell communication and trajectory analysis provided a framework for understanding cell-cell interactions and the differentiation of trophoblasts into BNCs in the placental microenvironment.Differential analysis of cell trajectories identified a set of genes involved in regulation of trophoblast differentiation.Additionally,spatial modules and co-variant genes that help shape specific tissue structures were identified.Together,these findings provide foundational insights into important biological pathways critical to the placental development and function in cows. 展开更多
关键词 Spatial transcriptomics Dairy cow PLACENTA GESTATION
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Modification of BCC phase and the enhanced reversible hydrogen storage properties of Ti-V-Fe-Mn alloys with varied V/Fe ratios
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作者 Xiang-feng Ma Xin Ding +4 位作者 En-lai Liu Rui-run Chen Xin-xiu Wang yong zhang and Jing-jie Guo 《China Foundry》 SCIE EI CAS CSCD 2024年第5期546-554,共9页
Ti-V-based alloys are proved of huge potential in storing hydrogen,but the incomplete reversible hydrogen storage capacity caused by overstability of V hydride has limited the large-scale application.In this study,Ti_... Ti-V-based alloys are proved of huge potential in storing hydrogen,but the incomplete reversible hydrogen storage capacity caused by overstability of V hydride has limited the large-scale application.In this study,Ti_(32)V_(40+x)Fe_(23-x)Mn_(5)(x=0,4,8,12,at.%)alloys were designed,and the effects of V/Fe ratio on phase constitution and hydrogen storage properties were investigated.The main phase of the alloys is body-centered cubic(BCC)phase,and the lattice constants of the BCC phase decrease with the decrease of V/Fe ratio.Moreover,C14 Laves phase exists in alloys with a Fe content of 19at.%to 23at.%.For hydrogenation,the C14 Laves phase can accelerate the hydrogen absorption rate,but the hydrogen absorption capacity is reduced.With the decrease of V/Fe ratio,the hydride gradually destabilizes.Owing to its large lattice constant and high hydrogen absorption phase content,the Ti_(32)V_(52)Fe_(11)Mn_(5)alloy shows the most enhanced hydrogen storage properties with hydrogenation and dehydrogenation capacities of 3.588wt.%at 298 K and 1.688wt.%at 343 K,respectively.The hydrogen absorption capacity of this alloy can be reserved to 3.574wt.%after 20 cycles of hydrogen absorption and desorption. 展开更多
关键词 hydrogen storage Ti-based alloy lattice constant BCC phase
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Distributed Graph Database Load Balancing Method Based on Deep Reinforcement Learning
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作者 Shuming Sha Naiwang Guo +1 位作者 Wang Luo yong zhang 《Computers, Materials & Continua》 SCIE EI 2024年第6期5105-5124,共20页
This paper focuses on the scheduling problem of workflow tasks that exhibit interdependencies.Unlike indepen-dent batch tasks,workflows typically consist of multiple subtasks with intrinsic correlations and dependenci... This paper focuses on the scheduling problem of workflow tasks that exhibit interdependencies.Unlike indepen-dent batch tasks,workflows typically consist of multiple subtasks with intrinsic correlations and dependencies.It necessitates the distribution of various computational tasks to appropriate computing node resources in accor-dance with task dependencies to ensure the smooth completion of the entire workflow.Workflow scheduling must consider an array of factors,including task dependencies,availability of computational resources,and the schedulability of tasks.Therefore,this paper delves into the distributed graph database workflow task scheduling problem and proposes a workflow scheduling methodology based on deep reinforcement learning(DRL).The method optimizes the maximum completion time(makespan)and response time of workflow tasks,aiming to enhance the responsiveness of workflow tasks while ensuring the minimization of the makespan.The experimental results indicate that the Q-learning Deep Reinforcement Learning(Q-DRL)algorithm markedly diminishes the makespan and refines the average response time within distributed graph database environments.In quantifying makespan,Q-DRL achieves mean reductions of 12.4%and 11.9%over established First-fit and Random scheduling strategies,respectively.Additionally,Q-DRL surpasses the performance of both DRL-Cloud and Improved Deep Q-learning Network(IDQN)algorithms,with improvements standing at 4.4%and 2.6%,respectively.With reference to average response time,the Q-DRL approach exhibits a significantly enhanced performance in the scheduling of workflow tasks,decreasing the average by 2.27%and 4.71%when compared to IDQN and DRL-Cloud,respectively.The Q-DRL algorithm also demonstrates a notable increase in the efficiency of system resource utilization,reducing the average idle rate by 5.02%and 9.30%in comparison to IDQN and DRL-Cloud,respectively.These findings support the assertion that Q-DRL not only upholds a lower average idle rate but also effectively curtails the average response time,thereby substantially improving processing efficiency and optimizing resource utilization within distributed graph database systems. 展开更多
关键词 Reinforcement learning WORKFLOW task scheduling load balancing
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MicroRNA-298 determines the radio-resistance of colorectal cancer cells by directly targeting human dual-specificity tyrosine(Y)-regulated kinase 1A
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作者 Mei-Zhu Shen yong zhang +6 位作者 Fang Wu Mei-Zhen Shen Jun-Lin Liang Xiao-Long zhang Xiao-Jian Liu Xin-Shu Li Ren-Sheng Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1453-1464,共12页
BACKGROUND Radiotherapy stands as a promising therapeutic modality for colorectal cancer(CRC);yet,the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission.AIM... BACKGROUND Radiotherapy stands as a promising therapeutic modality for colorectal cancer(CRC);yet,the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission.AIM To elucidate the role played by microRNA-298(miR-298)in CRC radio-resistance.METHODS To establish a radio-resistant CRC cell line,HT-29 cells underwent exposure to 5 gray ionizing radiation that was followed by a 7-d recovery period.The quantification of miR-298 levels within CRC cells was conducted through quantitative RT-PCR,and protein expression determination was realized through Western blotting.Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and proliferation by clonogenic assay.Radio-induced apoptosis was discerned through flow cytometry analysis.RESULTS We observed a marked upregulation of miR-298 in radio-resistant CRC cells.MiR-298 emerged as a key determinant of cell survival following radiation exposure,as its overexpression led to a notable reduction in radiation-induced apoptosis.Intriguingly,miR-298 expression exhibited a strong correlation with CRC cell viability.Further investigation unveiled human dual-specificity tyrosine(Y)-regulated kinase 1A(DYRK1A)as miR-298’s direct target.CONCLUSION Taken together,our findings underline the role played by miR-298 in bolstering radio-resistance in CRC cells by means of DYRK1A downregulation,thereby positioning miR-298 as a promising candidate for mitigating radioresistance in CRC. 展开更多
关键词 MicroRNA-298 Human dual-specificity tyrosine(Y)-regulated kinase 1A Colorectal cancer Radio-resistance p53 binding protein 1
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Research on Feature Matching Optimization Algorithm for Automotive Panoramic Surround View System
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作者 Guangbing Xiao Ruijie Gu +1 位作者 Ning Sun yong zhang 《Computer Systems Science & Engineering》 2024年第5期1329-1348,共20页
In response to the challenges posed by insufficient real-time performance and suboptimal matching accuracy of traditional feature matching algorithms within automotive panoramic surround view systems,this paper has pr... In response to the challenges posed by insufficient real-time performance and suboptimal matching accuracy of traditional feature matching algorithms within automotive panoramic surround view systems,this paper has proposed a high-performance dimension reduction parallel matching algorithm that integrates Principal Component Analysis(PCA)and Dual-Heap Filtering(DHF).The algorithm employs PCA to map the feature points into the lower-dimensional space and employs the square of Euclidean distance for feature matching,which significantly reduces computational complexity.To ensure the accuracy of feature matching,the algorithm utilizes Dual-Heap Filtering to filter and refine matched point pairs.To further enhance matching speed and make optimal use of computational resources,the algorithm introduces a multi-core parallel matching strategy,greatly elevating the efficiency of feature matching.Compared to Scale-Invariant Feature Transform(SIFT)and Speeded Up Robust Features(SURF),the proposed algorithm reduces matching time by 77%to 80%and concurrently enhances matching accuracy by 5%to 15%.Experimental results demonstrate that the proposed algorithmexhibits outstanding real-time matching performance and accuracy,effectivelymeeting the feature-matching requirements of automotive panoramic surround view systems. 展开更多
关键词 Featurematching automotive panoramic surround view system principal component analysis euclidean distance dual-heap filtering
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Exploring Sulfur Chemistry in TMC-1 with NSRT
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作者 Wasim Iqbal Xiaohu Li +19 位作者 Juan Tuo Ryszard Szczerba Yanan Feng Zhenzhen Miao Jiangchao Yang Jixing Ge Gleb Fedoseev Donghui Quan Qiang Chang Chuan-Lu Yang Tao Yang Gao-Lei Hou yong zhang Xuan Fang Xia zhang Fangfang Li Rong Ma Xiaomin Song Zhiping Kou Yuxuan Sun 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期129-132,共4页
There have been several studies on sulfur depletion in dense cores like TMC-1(Taurus Molecular Cloud 1),employing updated reaction networks for sulfur species to explain the missing sulfur in the gas within dense clou... There have been several studies on sulfur depletion in dense cores like TMC-1(Taurus Molecular Cloud 1),employing updated reaction networks for sulfur species to explain the missing sulfur in the gas within dense clouds.Most of these studies used a C/O ratio of 0.7 or lower.We present NSRT(NanShan 26m Radio Telescope)observations of TMC-1 alongside results from time-dependent chemical simulations using an updated chemical network.Our findings highlight the impact of the C/O ratio on the gas-phase evolution of C2S and C3S.The simulation results show that the C/O ratio is an important parameter,playing a fundamental role in determining the gas-phase abundances of sulfur species in dense cores. 展开更多
关键词 SULFUR SULFUR depletion
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综合性高分子化学实验设计:硬质聚氨酯泡沫材料制备与性能表征
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作者 杨凯 毕戈华 +4 位作者 张永 靳德林 徐子崴 王倩 邢令宝 《大学化学》 CAS 2024年第4期206-212,共7页
针对传统“高分子化学实验”课程教学中,存在综合性、研究性实验项目少,不能支撑“新工科”人才实践和创新能力培养要求等问题,开发了硬质聚氨酯泡沫材料制备与性能表征综合实验项目。采用全水发泡体系,通过调节发泡剂和阻燃剂用量,制... 针对传统“高分子化学实验”课程教学中,存在综合性、研究性实验项目少,不能支撑“新工科”人才实践和创新能力培养要求等问题,开发了硬质聚氨酯泡沫材料制备与性能表征综合实验项目。采用全水发泡体系,通过调节发泡剂和阻燃剂用量,制备了七组聚氨酯泡沫材料,然后采用国标方法表征了材料的表观密度、压缩强度和氧指数,分析了发泡剂和阻燃剂不同配比对泡沫材料性能的影响及原因。本实验贴近高分子产业发展,突出综合性和研究性,教学过程实现了基本实验技能与科学研究方法训练的有机结合,有助于提升高分子化学实验课程“创新性、高阶性和挑战度”,支撑“新工科”人才培养。 展开更多
关键词 新工科 硬质聚氨酯泡沫 高分子化学实验 综合实验项目
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Effects of 8-OHdG,H-FABP and CRP on the Development of Ischemic Cardiomyopathy
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作者 Qingquan WU yong zhang Xiuxian HUANG 《Medicinal Plant》 2024年第4期69-72,共4页
[Objectives]To analyze the relationship between serum 8-hydroxydeoxyguanosine(8-OHdG),heart fatty acid-binding protein(H-FABP),C-reactive protein(CRP)levels and clinical efficacy and short-term prognosis in patients w... [Objectives]To analyze the relationship between serum 8-hydroxydeoxyguanosine(8-OHdG),heart fatty acid-binding protein(H-FABP),C-reactive protein(CRP)levels and clinical efficacy and short-term prognosis in patients with ischemic cardiomyopathy.[Methods]The clinical data of 100 patients with ischemic cardiomyopathy from October 2021 to November 2022 were retrospectively analyzed,and the serum levels of 8-OHdG,H-FABP and CRP were compared before and one week after treatment.The patients were followed up for 12 months after discharge,and the incidence of major adverse cardiovascular events(MACE)was counted during the follow-up period.Univariate and multivariate Logistic regression analysis were used to analyze the prognostic factors of patients with ischemic cardiomyopathy in the near future,and the predictive value of serum 8-OHdG,H-FABP and CRP levels for the prognosis of patients was evaluated by ROC curve.[Results]After 1 week of treatment,the serum levels of 8-OHdG,H-FABP and CRP in patients with ischemic cardiomyopathy were significantly lower than those before treatment(P<0.05).During the follow-up period,34 patients developed MACE;the serum levels of 8-OHdG,H-FABP and CRP in the MACE group were higher than those in the non-MACE group,and the differences were statistically significant(P<0.05).Multivariate Logistic regression analysis showed that 8-OHdG,H-FABP and CRP were the risk factors of MACE in patients with ischemic cardiomyopathy(P<0.05).ROC curve analysis showed that the combined prediction of 8-OHdG,H-FABP and CRP for MACE in patients with ischemic cardiomyopathy was higher than that of CRP,H-FABP and 8-OHdG alone(P<0.05).[Conclusions]8-OHdG,H-FABP and CRP are closely related to the clinical efficacy and short-term prognosis of patients with ischemic cardiomyopathy,and the detection of serum 8-OHdG,H-FABP and CRP levels can help to evaluate the clinical efficacy and short-term prognosis of patients with ischemic cardiomyopathy. 展开更多
关键词 chemic cardiomyopathy 8-hydroxydeoxyguanosine heart type fatty acid binding protein C-reactive protein Clinical efficacy Short-term prognosis
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