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The role of corneal endothelium in macular corneal dystrophy development and recurrence
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作者 Bi-Ning Zhang Benxiang Qi +13 位作者 Chunxiao Dong Bin Zhang Jun Cheng Xin Wang Suxia li Xiaoyun Zhuang Shijiu Chen Haoyun Duan dewei li Sujie Zhu Guoyun li Yihai Cao Qingjun Zhou lixin Xie 《Science China(Life Sciences)》 SCIE CAS CSCD 2024年第2期332-344,共13页
Macular corneal dystrophy(MCD)is a progressive,bilateral stromal dystrophic disease that arises from mutations in carbohydrate sulfotransferase 6(CHST6).Corneal transplantation is the ultimate therapeutic solution for... Macular corneal dystrophy(MCD)is a progressive,bilateral stromal dystrophic disease that arises from mutations in carbohydrate sulfotransferase 6(CHST6).Corneal transplantation is the ultimate therapeutic solution for MCD patients.Unfortunately,postoperative recurrence remains a significant challenge.We conducted a retrospective review of a clinical cohort comprising 102 MCD patients with 124 eyes that underwent either penetrating keratoplasty(PKP)or deep anterior lamellar keratoplasty(DALK).Our results revealed that the recurrence rate was nearly three times higher in the DALK group(39.13%,9/23 eyes)compared with the PKP group(10.89%,11/101 eyes),suggesting that surgical replacement of the corneal endothelium for treating MCD is advisable to prevent postoperative recurrence.Our experimental data confirmed the robust m RNA and protein expression of CHST6 in human corneal endothelium and the rodent homolog CHST5 in mouse endothelium.Selective knockdown of wild-type Chst5 in mouse corneal endothelium(AC^(siChst5)),but not in the corneal stroma,induced experimental MCD with similar extracellular matrix synthesis impairments and corneal thinning as observed in MCD patients.Mice carrying Chst5 point mutation also recapitulated clinical phenotypes of MCD,along with corneal endothelial abnormalities.Intracameral injection of wild-type Chst5 rescued the corneal impairments in AC^(siChst5)mice and retarded the disease progression in Chst5 mutant mice.Overall,our study provides new mechanistic insights and therapeutic approaches for MCD treatment by highlighting the role of corneal endothelium in MCD development. 展开更多
关键词 macular corneal dystrophy RECURRENCE corneal endothelium keratan sulfate penetrating keratoplasty
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草坪腐霉病的发生与防治 被引量:2
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作者 赵桂华 dewei li +2 位作者 吴玉柱 管斌 谢春芹 《林业实用技术》 北大核心 2005年第8期32-34,共3页
关键词 草坪品种 腐霉病 病害类型 防治 优良品种 种子传播 生长不良 生物入侵 国外
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Estimation method for a skip-stop operation strategy for urban rail transit in China 被引量:8
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作者 Zhichao Cao Zhenzhou Yuan dewei li 《Journal of Modern Transportation》 2014年第3期174-182,共9页
The skip-stop operation strategy (SOS) is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance a... The skip-stop operation strategy (SOS) is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance advantages, in that the total trip time can be reduced depending on the number of skipped stations, crowds of passengers can be rapidly evacuated at congested stations in peak periods, and the cost to transit companies is reduced. There is a contradiction between reducing the trip time under the SOS and increasing the passengers' waiting times under an all-stop scheme. Given this situation, the three objectives of our study were to minimize the waiting and trip times of all passengers and the travel times of trains. A comprehensive estimation model is presented for the SOS. The mechanism through which the trip time for all passengers is affected by the SOS is analyzed in detail. A 0-I integer programming formulation is established for the three objectives, and is solved using a tabu search algorithm. Finally, an example is presented to demonstrate that the estimation method for the SOS is capable of optimizing the timetable and operation schemes for a Chinese urban rail transit network. 展开更多
关键词 rail transit algorithm Skip-stop operation strategy network Integer programming Chinese urban GENETIC
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Distributed Subgradient Algorithm for Multi-Agent Optimization With Dynamic Stepsize 被引量:3
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作者 Xiaoxing Ren dewei li +1 位作者 Yugeng Xi Haibin Shao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1451-1464,共14页
In this paper,we consider distributed convex optimization problems on multi-agent networks.We develop and analyze the distributed gradient method which allows each agent to compute its dynamic stepsize by utilizing th... In this paper,we consider distributed convex optimization problems on multi-agent networks.We develop and analyze the distributed gradient method which allows each agent to compute its dynamic stepsize by utilizing the time-varying estimate of the local function value at the global optimal solution.Our approach can be applied to both synchronous and asynchronous communication protocols.Specifically,we propose the distributed subgradient with uncoordinated dynamic stepsizes(DS-UD)algorithm for synchronous protocol and the AsynDGD algorithm for asynchronous protocol.Theoretical analysis shows that the proposed algorithms guarantee that all agents reach a consensus on the solution to the multi-agent optimization problem.Moreover,the proposed approach with dynamic stepsizes eliminates the requirement of diminishing stepsize in existing works.Numerical examples of distributed estimation in sensor networks are provided to illustrate the effectiveness of the proposed approach. 展开更多
关键词 Distributed optimization dynamic stepsize gradient method multi-agent networks
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Model predictive control for constrained uncertain piecewise linear systems
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作者 dewei li Yugeng XI Yuanyuan ZOU 《控制理论与应用(英文版)》 EI CSCD 2013年第2期230-236,共7页
For constrained piecewise linear (PWL) systems, the possible existing model uncertainty will bring the difficulties to the design approaches of model predictive control (MPC) based on mixed integer programming (... For constrained piecewise linear (PWL) systems, the possible existing model uncertainty will bring the difficulties to the design approaches of model predictive control (MPC) based on mixed integer programming (MIP). This paper combines the robust method and hybrid method to design the MPC for PWL systems with structured uncertainty. For the proposed approach, as the system model is known at current time, a free control move is optimized to be the current control input. Meanwhile, the MPC controller uses a sequence of feedback control laws as the future control actions, where each feedback control law in the sequence corresponds to each partitions and the arbitrary switching technique is adopted to tackle all the possible switching. Furthermore, to reduce the online computational burden of MPC, the segmented design procedure is suggested by utilizing the characteristics of the proposed approach. Then, an offline design algorithm is proposed, and the reserved degree of freedom can be online used to optimize the control input with lower computational burden. 展开更多
关键词 Model predictive control Constrained piecewise linear system Structured uncertainty Segmented designprocedure
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巯基化活性炭靶向捕获电子废弃物酸浸液中金离子 被引量:2
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作者 李敏 姚子威 +8 位作者 陈以頔 李德伟 邵家创 董浩 孟竹 杨利明 任伟 罗旭彪 邵鹏辉 《Science Bulletin》 SCIE EI CAS CSCD 2023年第11期1095-1099,M0003,共6页
电子废弃物中回收金兼具污染治理、资源循环双重目的,是环境高水平保护、经济高质量发展的必要要求.吸附法是湿法回收金属资源的有效方法,但含金电子废弃物的浸出液都呈现强酸性和强氧化性;目前从该体系中靶向捕捉金离子仍存在巨大挑战... 电子废弃物中回收金兼具污染治理、资源循环双重目的,是环境高水平保护、经济高质量发展的必要要求.吸附法是湿法回收金属资源的有效方法,但含金电子废弃物的浸出液都呈现强酸性和强氧化性;目前从该体系中靶向捕捉金离子仍存在巨大挑战.本文报道了一种巯基功能化的秸秆基活性炭,在强酸、强氧化性体系中实现了金离子的靶向捕获,其最大吸附容量可达5309 mg/g,选择性系数达到1.21×10^(6);吸附后的材料经煅烧得到金单质,其纯度高达99.9%.机理研究表明,巯基电位选择性诱导金离子优先还原,并促发了吸附-还原过程自发进行.由于量子尺寸效应,被还原的金簇在炭材料表面积累,处于“激发状态”的纳米金簇,将进一步诱导还原体系中金离子,呈现一种自促进作用.研究实现了复杂苛刻酸浸液中金元素的靶向回收,为电子废弃物高质循环利用提供了新思路. 展开更多
关键词 电子废弃物 强氧化性 污染治理 资源循环 循环利用 选择性系数 量子尺寸效应 金离子
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角膜屈光术前睑板腺形态的影响因素
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作者 田乐 李德卫 +3 位作者 彭予苏 张飞飞 万鲁芹 陈敏 《中华眼视光学与视觉科学杂志》 CAS CSCD 2023年第8期589-595,共7页
目的:观察行角膜屈光术前屈光不正患者双眼上下睑板腺的腺体形态,并对影响睑板腺形态变化的因素进行分析。方法:回顾性病例对照研究。随机选择2021年9月至2022年3月于山东第一医科大学附属青岛眼科医院就诊,拟行屈光矫正手术的近视散光... 目的:观察行角膜屈光术前屈光不正患者双眼上下睑板腺的腺体形态,并对影响睑板腺形态变化的因素进行分析。方法:回顾性病例对照研究。随机选择2021年9月至2022年3月于山东第一医科大学附属青岛眼科医院就诊,拟行屈光矫正手术的近视散光患者244例(488眼),其中男101例(202眼),女143例(286眼),年龄17~51岁。根据性别分为男性组和女性组;男女组分别按年龄再细分为≤25岁组、>25~<35岁组、≥35岁组;根据有无软性角膜接触镜配戴史分为对照组和配戴组;根据等效球镜度(SE)分为>-6.00 D组和≤-6.00 D组。采用眼表综合分析仪检测患者的眼表功能指标,比较不同分组患者的泪河高度(TMH)、首次泪膜破裂时间(fNIBUT)、平均泪膜破裂时间(avNIBUT)、睑板腺缺失率、睑板腺腺体弯曲数量的差异。不同组间各指标的比较采用秩和检验。睑板腺缺失率与性别的相关性分析采用Eta系数。睑板腺缺失率与年龄、接触镜配戴时间、SE、TMH等指标的相关性分析采用Spearman相关分析。结果:不同性别组间fNIBUT、avNIBUT、睑板腺缺失率的差异均有统计学意义(Z=-2.39,P=0.017;Z=-3.19,P=0.001;Z=-3.46,P=0.001)。男性患者不同年龄组各组间fNIBUT差异有统计学意义(H=6.42,P=0.040),其余各项眼表功能指标差异均无统计学意义(均P>0.05)。女性患者不同年龄组各组间TMH、fNIBUT、avNIBUT、睑板腺缺失率、睑板腺腺体弯曲数量差异均无统计学意义(均P>0.05)。有无软性角膜接触镜配戴组间avNIBUT、睑板腺缺失率差异有统计学意义(Z=-2.02,P=0.043;Z=-3.43,P=0.001)。SE>-6.00 D组和≤-6.00 D组间睑板腺缺失率差异有统计学意义(Z=-1.99,P=0.047)。睑板腺缺失率与性别、年龄、软性角膜接触镜配戴时间、SE、腺体弯曲数量均有相关性(Eta系数1.0;r=0.10,P=0.036;r=0.16,P<0.001;r=-0.11,P=0.013;r=0.21,P<0.001)。结论:睑板腺形态变化主要表现为睑板腺腺体缺失、腺体弯曲数量增加,影响患者睑板腺缺失率的高危因素包括女性和高度近视。角膜屈光手术围手术期应特别关注女性高度近视患者的眼表功能情况。 展开更多
关键词 睑板腺 干眼 角膜接触镜 泪膜 睑板腺功能障碍
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The mechanism of deep material transport and seismogenic environment of the Xiaojiang fault system revealed by 3-D magnetotelluric study 被引量:2
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作者 Nian YU Xuben WANG +4 位作者 dewei li Xin li Enci WANG Wenxin KONG Tianyang li 《Science China Earth Sciences》 SCIE EI CSCD 2022年第6期1128-1145,共18页
The Xiaojiang fault system(XJFS), located to the southeast of the Tibetan Plateau, has a complicated tectonic history and is an ideal location to study the Tibetan Plateau in terms of its deep material transport mecha... The Xiaojiang fault system(XJFS), located to the southeast of the Tibetan Plateau, has a complicated tectonic history and is an ideal location to study the Tibetan Plateau in terms of its deep material transport mechanism and the effects of past tectonic events. In this study, broadband and long-period magnetotelluric data were collected above this fault system and inverted to build a 3-D resistivity model of the lithosphere. As shown in the model, at upper-middle crustal depths, three high-resistivity anomalies separate the strike-slip faults located in the study area, which may be the remnants of the Emeishan large igneous province that was destroyed and modified by Cenozoic crustal activity. The lower crust is characterized by significant lowresistivity anomalies that extend downward to the upper mantle. The low-resistivity anomalies in the upper crust may be caused by brines or/and conductive minerals(e.g., graphite and sulfides), and the possible reason for the low-resistivity anomalies that were imaged in the lower crust and upper mantle may be the presence of hydrogen in nominally anhydrous minerals and partial melts. According to the seismic activity distribution and resistivity structure, we propose dividing the seismic activity of the study area into three categories: tectonic earthquakes, earthquakes with no active faults on the surface, and other scattered earthquakes with no general features. Seismic activities are controlled by tectonic activities, fluid transportation, and the adjustment of the Earth's stress field. It is believed that there is a mutually reinforcing relationship between seismic activity and deep fluids. Fluids could lower the frictional force in faults, promote movement, and thus induce earthquakes;on the other hand,seismic activities and the long-term strike-slip movements of faults could generate heat and increase the connectivity of fluids,which decreases the strength of the crust and facilitates the flow of fluids. Based on the resistivity model, it is demonstrated that the present tectonic activity in the XJFS is complicated and characterized by rigid block extrusion along strike-slip faults in the upper crust, ductile deformation with channel flow in the lower crust, and the upwelling of mantle materials. In combination with previous studies, our results indicate that the weak crustal materials from the Tibetan Plateau are blocked by(1) the lithosphere modified by the Emeishan plume and(2) the South China block when flowing through the Sichuan-Yunnan block. Therefore,these weak materials turn to the southwest direction along the XJFS, then pass through the Red River fault and enter the Indochina block. 展开更多
关键词 The Xiaojiang fault MAGNETOTELLURIC Seismogenic environment Emeishan mantle plume Crustal flow
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