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颅内多发动脉瘤长期随访一例

中国现代神经疾病杂志 2024年第8期24卷 689-694页

作者：王时强何小燕耿涛彭昌兴贵州省黔西南州人民医院神经外科兴义562400

患者女性,50岁,因头痛、呕吐1小时,于2014年2月15日16∶00入院。患者1小时前无明显诱因出现搏动性头痛,以左侧眼眶周围疼痛为主,伴恶心、非喷射状呕吐胃内容物数次(约300 ml),无呕血、咖啡样物,无偏瘫、偏盲、失语、复视、大小便失禁等... 详细信息

患者女性,50岁,因头痛、呕吐1小时,于2014年2月15日16∶00入院。患者1小时前无明显诱因出现搏动性头痛,以左侧眼眶周围疼痛为主,伴恶心、非喷射状呕吐胃内容物数次(约300 ml),无呕血、咖啡样物,无偏瘫、偏盲、失语、复视、大小便失禁等,急诊至我院,头部CT显示蛛网膜下腔出血,收入神经外科。患者否认合并高血压、糖尿病、冠心病,否认细菌性痢疾、结核、肝炎、伤寒等传染性疾病病史,否认手术、输血、外伤史,否认药物、食物过敏史,预防接种史不详;否认吸烟、饮酒、药物嗜好,否认工业毒物、粉尘及放射性物质接触史,否认治游史;家族中无类似疾病及遗传性疾病病史。

关键词：颅内动脉瘤栓塞治疗性复发随访研究病例报告

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基于重叠网格的阀芯振荡诱导空化的数值模拟

液压气动与密封 2024年第3期44卷 47-52页

作者：王世强马壮朱斌权张旭闵为郑直兰州理工大学能源与动力工程学院甘肃兰州730050

锥阀作为调压阀在工作过程中受到外部激励作用不可避免的会发生轴向振荡,诱导流场中出现空化现象,空化初生、发展及溃灭与阀芯振荡耦合在一起,导致整个液压系统的压力发生大幅波动。针对这一问题,基于OpenFOAM开源平台二次开发出具有动... 详细信息

锥阀作为调压阀在工作过程中受到外部激励作用不可避免的会发生轴向振荡,诱导流场中出现空化现象,空化初生、发展及溃灭与阀芯振荡耦合在一起,导致整个液压系统的压力发生大幅波动。针对这一问题,基于OpenFOAM开源平台二次开发出具有动态重叠网格功能的两相空化流求解器,对阀芯振荡诱导空化现象进行数值模拟,结合实验与数值计算结果得出:阀芯振荡关阀阶段阀腔中油液受到惯性作用向出口流动,产生大范围低压区,在低压影响下促使气核剧烈膨胀,在阀腔下游产生二次空化;阀芯振荡开阀阶段阀口处压力梯度大,压差驱动油液高速通过阀口产生射流,导致阀口处形成射流空化,这将为高性能液压阀的设计提供理论依据。

关键词：阀芯振荡空化重叠网格 OpenFOAM

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液压锥阀启闭过程及空化的研究

液压气动与密封 2024年第3期44卷 36-41页

作者：马壮王世强朱斌权张旭闵为郑直兰州理工大学能源与动力工程学院甘肃兰州730050

在锥阀启闭过程中,阀口处流道形状较为复杂,这会促使阀口处产生空化,从而对液压系统的稳定性和可靠性产生不利影响。通过OpenFOAM 3个分支版本的foam-extend-4.1开发出应用浸没边界法的两相空化流动求解器,使用该求解器在阀芯启闭过程... 详细信息

在锥阀启闭过程中,阀口处流道形状较为复杂,这会促使阀口处产生空化,从而对液压系统的稳定性和可靠性产生不利影响。通过OpenFOAM 3个分支版本的foam-extend-4.1开发出应用浸没边界法的两相空化流动求解器,使用该求解器在阀芯启闭过程及阀口空化的数值模拟研究中尝试应用浸没边界法且得到了较好的计算效果。研究表明,开阀时的空化是因为阀口处高速射流所导致的射流空化,关阀时的空化是由于液压油惯性导致的二次空化。

关键词：阀芯启闭浸没边界法阀口空化 OpenFOAM

The Removal and Remediation of Phenanthrene and Pyrene in Soil by Mixed Cropping of Alfalfa and Rape

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Agricultural Sciences in China 2008年第11期7卷 1355-1364页

作者： PAN Sheng-wang WEI shi-qiang YUAN Xin CAO Sheng-xian Key Laboratory of Agricultural Resources and Environment in Chongqing College of Resources and Environment Southwest University Chongqing 400716 P.R.China

The mechanisms and efficiencies of the removal and remediation of polycyclic aromatic hydrocarbons （PAHs） in soils by different planting patterns with rape （Brassica campestris） and alfalfa （Medicago sativa） were studied by pot experiments in a greenhouse. Results showed that the remediation efficiencies under mixed cropping of alfalfa and rape significantly exceeded those under single cropping when the initial concentrations of phenanthrene and pyrene were at 20.05-322.06 mg kg^-1 and 20.24-321.42 mg kg^-1, respectively. After 70 days plantation of crops, the contents of extractable PAHs in soils under mixed cropping were much lower than those under single cropping. About 65.17-83.52% of phenanthrene and 60.09%- 75.34% ofpyrene was removed from the soils under mixed cropping, respectively, which were averagely 43.26 and 40.38% for phenanthrene, and 11.03 and 16.29% for pyren higher than those under single cropping. Alfalfa or rape did absorb and accumulate PAHs from the soils apparently; the PAHs concentrations in plants monotonically increased with the increase of initial PAHs concentrations in soil; the accumulations of PAHs in plants showed following sequence as roots 〉 above parts, phenanthrene 〉 pyrene and single cropping 〉 mixed cropping at same contamination level. Despite the presence of vegetation significantly enhanced the remediation of PAHs in soils, contributions of abiotic loss, plant uptake, accumulation and microbial degradation was much lower than those of plant-microbial interactions in the process of phytoremediation. Thus plant-microbial interactions are the main mechanisms for the remediation enhancement of soil PAHs pollution under mixed cropping models. Results suggested a feasibility of the establishment of multi-species phytoremediation for the improvement of remediation efficiencies of PAHs, which may decrease accumulations of PAHs in crops and thus reduce their risks.

关键词： phytoremediation polycyclic aromatic hydrocarbons mixed cropping models plant-microbial interactions soil

Application of brassinolide alleviates cold stress at the booting stage of rice

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Journal of Integrative Agriculture 2020年第4期19卷 975-987页

作者： wang shi-qiang ZHAO Hai-hong ZHAO Li-ming GU Chun-mei NA Yong-guang XIE Bao-sheng CHENG shi-hua PAN Guo-jun Postdoctoral Scientific Research Station of Heilongjiang Academy of Agricultural Sciences Harbin 150086P.R.China Rice Research Institute of Land Reclamation Academy in Heilongjiang Province Jiamusi 154007P.R.China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006P.R.China Jiamusi Branch of Heilongjiang Academy of Agricultural Sciences Jiamusi 154007P.R.China Jiamusi Rice Research Institute Heilongjiang Academy of Agriculture SciencesJiamusi 154026P.R.China

The objective of the study was to determine the physiological mechanisms of plants in response to brassinolide(BR) alleviating cold water stress on rice. In this study, physiological responses of rice to exogenous BR and cold water submergence were investigated using the chilling-tolerant cultivar Kongyu 131(KY131) and the chilling-sensitive cultivar Kenjiandao 6(KJD6). A total of 2 mg L^-1 BR increased activities of superoxide dismutase(SOD) and peroxidase(POD) and the contents of soluble sugar, soluble protein, and chlorophyll, but decreased the malondialdehyde(MDA) content in KY131 and KJD6 under cold water stress. The observed decreases in SOD and POD activities and MDA content recovered quickly after plants were returned to irrigation with water at temperatures of about 23.0°C in 2014. Additionally, the contents of nitrogen(N), phosphorous(P), and potassium(K) were increased by BR treatment under cold water stress. Exposure to BR also raised the percentage of high effective leaf area and leaf area index at the heading stage. Furthermore, it promoted soluble sugar synthesis, increased the rate of dry matter accumulation, and enhanced the export and translocation rates of the stem-sheath. The yield in KJD6 was significantly(P≤0.01 and P≤0.05) higher than that of the control in 2013 and 2014, respectively. The effect of BR treatment on rice leaf SOD and POD activities, MDA, chlorophyll, P, and stem-sheath K contents were more significant in KJD6 than in KY131. In conclusion, exogenous BR effectively reduced the physiological and metabolic damage in rice due to cold stress at the booting stage, promoted functional recovery in plants that received irrigation with water at a normal temperature following cold stress, and mitigated the effects of cold water stress on *** two varieties exhibited differential responses to BR;the weaker cold-resistant variety was more sensitive to BR and displayed stronger responses to exogenous BR.

关键词： rice cold water stress brassinolide physiological characteristics

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

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一次由海风锋激发的下击暴流天气过程分析

广东气象 2024年第1期46卷 9-13页

作者：王世强黄菲詹棠张金清李伟明珠海市公共气象服务中心广东珠海519000 珠海市国家观象台广东珠海519000

利用珠海市地面自动站观测资料、MICAPS资料和横琴X波段双偏振相控阵雷达资料,对珠海市一次由海风锋激发的下击暴流天气过程进行分析,结果表明:(1)该次下击暴流过程发生前,大气层结呈现“上干下湿”结构,温度垂直递减率大,CAPE大,环境... 详细信息

利用珠海市地面自动站观测资料、MICAPS资料和横琴X波段双偏振相控阵雷达资料,对珠海市一次由海风锋激发的下击暴流天气过程进行分析,结果表明:(1)该次下击暴流过程发生前,大气层结呈现“上干下湿”结构,温度垂直递减率大,CAPE大,环境条件有利于雷雨大风天气发生;(2)该次伴随下击暴流的强对流系统主要由珠海东部沿岸形成的海风锋触发,并伴有中气旋出现;(3)下击暴流发生前,处于低层反射率大值期,X波段相控雷达可以清晰观测到强反射率因子下降、中层径向速度辐合、近地面气流辐散等现象。

关键词：天气学下击暴流海风锋中气旋相控阵雷达

Coordination environments build up and tune a superior synergistic “genome” toward novel trifunctional (TM-N_(x)O_(4−x))@g- C_(16)N_(3)-H_(3): High-throughput inspection of ultra-high activity for water splitting and oxygen reduction reactions

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Nano Research 2024年第4期17卷 2337-2351页

作者： Chunyao Fang Xian wang qiang Zhang Xihang Zhang Chenglong shi Jingcheng Xu Mengyu Yang Department of Physics University of Shanghai for Science and TechnologyShanghai 200093China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China

Emerging as a prominent area of focus in energy conversion and storage technologies,the development of highly active metal-based single-atom catalysts(SACs)holds great signiﬁcance in searching alternatives to replace precious metals toward the efficient,stable,and low-cost hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR).Combining the tremendous tunability of ligand and coordination environment with rich metal-based electrocatalysts can create breakthrough opportunities for achieving both high stability and ***,we propose a novel and stable holey graphene-like carbon nitride monolayer g-C_(16)N5(N_(4)@g-C_(16)N_(3))stoichiometries interestingly behaving as a natural substrate for constructing SACs((TM-N_(4))@g-C_(16)N_(3)),whose evenly distributed holes map rich and uniform nitrogen coordination positions with electron-rich lone pairs for anchoring transition metal(TM)***,we employed density functional theory(DFT)calculations to systematically investigate the electrocatalytic activity of(TM-N_(4))@g-C_(16)N_(3) toward HER/OER/ORR,meanwhile considering the synergistic modulation of H-loading and O-coordination((TM-N_(x)O_(4-x))@g-C_(16)N_(3)^(-)H_(3),x=0–4).Together a“four-step procedure”screening mechanism with the first-principles high-throughput calculations,we find that(Rh-N_(4))and(Ir-N_(2)O_(2)-II)distributed on g-C_(16)N_(3)^(-)H_(3) can modulate the adsorption strength of the adsorbates,thus achieving the best HER/OER/ORR performance among 216 candidates,and the lowest overpotential of 0.098/0.3/0.46 V and 0.06/0.48/0.45 V,***,the d-band center,crystal orbital Hamilton population(COHP),and molecular orbitals are used to reveal the OER/ORR activity ***,the Rh/Ir-d orbital is dramatically hybridized with the O-p orbital of the oxygenated adsorbates,so that the lone-electrons incipiently locate at the antibonding orbital pair up and popula

关键词： single atom catalysts loading and coordination hydrogen evolution reaction oxygen evolution reaction oxygen reduction reaction

Electrophysiology of hyperpolarization-activated cyclic nucleotidegated cation channel 2 and hyperpolarization-activated cyclic nucleotide-gated cation channel 4 expressed in HEK293 cells

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Chinese Medical Journal 2007年第22期120卷 2039-2041页

作者： LI Chun GUO Ji-hong LI Ji-wen LIU Yuan-wei HAO Xue-mei ZHANG Ping wang shi-qiang Division of Cardiac Electrophysiology Department of Internal Medicine Beijing University People＇s Hospital Beijing 100044 China State Key Laboratory of Biomembrane and Membrane Biotechnology College of Life Sciences Peking University Beijing 100084 China

The action potential of pacemaker cells in the sino-atrial node forms the automatic rhythm of the heart. The automatic depolarization in phase 4 is me DaSlS of the automaticity in pacemaker cells. Many currents are included in phase 4, such as calcium current, TTX-sensitive sodium current, sustained inward current （Isi）, decay of delayed rectifier potassium current, etc. Funny current （If） has long been recognized as important in this phase and is activated at hyperpolarized potentials during cell diastole and in turn activates other currents to form automatic depolarization.

关键词： hyperpolarization-activated cyclic nucleotide-gated potassium channel HEK293 cell whole cell