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基于.Net的System._ComObject类型辨析
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作者 骆文亮 陈伟 《信息技术》 2010年第1期85-86,107,共3页
针对在.NET平台下对COM组件进行交互编程时,遇到调用函数返回值的类型是System._ComObject而无法得到其真正类型的问题,以.NET框架与COM接口之间的通讯机制为出发点,研究和总结了System._ComObject产生的原因,最后给出了解决办法和应用... 针对在.NET平台下对COM组件进行交互编程时,遇到调用函数返回值的类型是System._ComObject而无法得到其真正类型的问题,以.NET框架与COM接口之间的通讯机制为出发点,研究和总结了System._ComObject产生的原因,最后给出了解决办法和应用实例。 展开更多
关键词 .NET框架 组件对象模型 运行时可调用包装 COM对象类型
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Diffuse Large B-Cell Lymphoma of the Central Nervous System. Immunophenotype, Clinicopathological Features and Differential Diagnosis
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作者 Mónica Belinda Romero-Guadarrama María Esther Gutiérrez Díaz-Ceballos +1 位作者 Fiacro Jiménez-Ponce Samantha Thingen-Velarde 《Open Journal of Pathology》 2012年第4期133-139,共7页
Background: Diffuse large B-cell lymphomas of the central nervous system (DLBCL CNS) represent less than 1% of all lymphomas and between 2% and 3% of all cerebral tumors. They occur in adults of 60 years of age or mor... Background: Diffuse large B-cell lymphomas of the central nervous system (DLBCL CNS) represent less than 1% of all lymphomas and between 2% and 3% of all cerebral tumors. They occur in adults of 60 years of age or more. The objective of this work is to describe the clinical-pathological characteristics, the immunophenotype and the differential diagnosis. Clinical Case: From the files of the surgical pathology unit we found four cases of primary diffuse large B cell lymphoma of the central nervous system in a 6-year period. Three corresponded to women over 47 years of age and the other to a 42-year-old man. The time of evolution was between 2 and 4 months. The symptoms were headache, blurred vision, hemiparesis, and seizures. Localization was in the pineal region, the frontal, parietal regions, and the right thalamus. Morphologically, large lymphoid cells with a diffuse growth pattern and necrosis were observed. Immunohistochemical markers, such as CD 20 and bcl2 were positive, one was positive to CD3. Expression of bcl6 and CD 10 was positive in one case, and MUM-1 was positive in three cases. All the cases were negative for Epstein-Barr virus. Conclusions: The diffuse large-B cell lymphoma of the central nervous system is rare. Its average age of presentation is at 60 years or older. The localization is in the pineal, frontal, parietal and thalamic regions. Three cases were originated by activated B lymphocyte (MUM-1 expression) and other from the Germinal Center (GC) (CD 10 expression). The clinical course was bad. The four patients died shortly after the diagnosis. 展开更多
关键词 PRIMARY LYMPHOMA CENTRAL Nervous system
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Application of Linear Thermodynamics to the Atmospheric System.Part Ⅱ: Exemplification of Linear Phenomenological Relations in the Atmospheric System
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作者 胡隐樵 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第5期767-776,共10页
The linear phenomenological relations in the atmospheric boundary layer are proved indirectly using observational facts to combine linear thermodynamic theory and similarity theory in the boundary layer. Furthermore, ... The linear phenomenological relations in the atmospheric boundary layer are proved indirectly using observational facts to combine linear thermodynamic theory and similarity theory in the boundary layer. Furthermore, it is proved that Ihe turbulent transport coefficients are in proportion to Ihe corresponding linear phenomenological coefficients. But the experimental facts show that the linear phenomenological relations are not (tenable in the atmospheric mixing layer because the turbulenl transport process is an intense non-linear process in the mixing layer. Hence the convection boundary layer is a thermodynamic stale in a non-linear region far from the equilibrium state. The geostrophic wind is a special cross-coupling phenomenon between the dynamic process and the thermodynamic process in the atmospheric system. It is a practical exemplification of a cross-coupling phenomenon in the atmospheric system. 展开更多
关键词 atmospheric system linear thermodynamics linear phenomenological relations turbulent transportation coefficient atmospheric boundary layer
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Neural Modeling of Multivariable Nonlinear Stochastic System. Variable Learning Rate Case
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作者 Ayachi Errachdi Ihsen Saad Mohamed Benrejeb 《Intelligent Control and Automation》 2011年第3期167-175,共9页
The objective of this paper is to develop a variable learning rate for neural modeling of multivariable nonlinear stochastic system. The corresponding parameter is obtained by gradient descent method optimization. The... The objective of this paper is to develop a variable learning rate for neural modeling of multivariable nonlinear stochastic system. The corresponding parameter is obtained by gradient descent method optimization. The effectiveness of the suggested algorithm applied to the identification of behavior of two nonlinear stochastic systems is demonstrated by simulation experiments. 展开更多
关键词 NEURAL NETWORKS MULTIVARIABLE system STOCHASTIC Learning RATE Modeling
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Comparison Between Diltiazem and Cedilanid-D on Ventricular Rate Control of Atrial Fibrillation and Their Effect on Atrioventricular Conduction System.
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作者 朱立光 Mohammad +1 位作者 AL Mamun(穆罕默德·艾·马蒙) 《South China Journal of Cardiology》 CAS 2005年第2期113-117,共5页
Objectives This randomized study was designed to compare the safety and efficacy of intravenous diltiazem versus intravenous cedilanid-D (deslanoside) for ventricular rate control in patients with atrial fibrillati... Objectives This randomized study was designed to compare the safety and efficacy of intravenous diltiazem versus intravenous cedilanid-D (deslanoside) for ventricular rate control in patients with atrial fibrillation (AF). Analysis of the effect on conduction system of these drugs was also performed. Methods Forty three patients with AF were randomly assigned to receive intravenous therapy with 0.25mg/kg diltiazem (n = 21) or 0.4rag cedilanid-D (n = 22). If not effective at 120 minutes (〈 20% decrease in pretreatment ventricular rate or can not convert to sinus rhythm= another dose of diltiazem or 0.2mg cedilanid-D was administered. Blood pressure and electrocardiographic recordings were performed before and after 5, 10, 20, 30, 60 minutes of drug administration. Further recordings were performed at 120 minutes in noneffective patients, and at 180 minutes in patients who received second time drug administration. To evaluate the effect on conduction system of these two drugs by measuring PA, AH and HV intervals using His bundle electrogram test another nineteen sinus rhythm patients were randomized to dihiazem (n=9) and cedilanid (n= 10) group. His bundle electrogram recordings were performed before and after 5, 10, 20 and 30 minutes of drug administration. Statistical significance was assessed with the use of t test, Fisher's exact test, ANOVA and LSD methodology. Results At baseline and after 5, 10, 20, 30, 60 minutes of drug administration the heart rates (mean±SD) were(133±15), (92±20), (87±22), (85 ±20), (85±21), (85 ±23)beats/minute in diltiazem group respectively and( 140±21 ), ( 122±24), (118±25), (110±26), (112±25), (110±28) beats/ minute in cedilanid-D group respectively. Heart rate reduction was higher in diltiazem group than cedilanid group during 5 (41±20 vs 17±14,P 〈 0.01); 10 (46±21 vs 22±20, P〈0.01); 20 (48±21 vs 29±22, P〈0.01 ) ; 30(48±22 vs 27±22,P〈0.01 )and 60 minutes (48±23 vs 29±24, P〈 0.05). Both drugs had no effect on both systolic and diastolic blood pressure (P 〉0.05) and no major side effects were noticed. Diltiazem maintained effective ventrieular rate in 20 patients, whereas eedilanid-D maintained in 15 patients within 180 minutes (95.2%vs 68.2%,P〈 0.05). There were no statistical significance in baseline heart rate, age and weight between the two groups. Both diltiazem and cedilanid-D can increase AH interval, but have no effect on HV and PA intervals in sinus rhythm patients. Conclusions Both dihiazem and eedilanid-D decrease ventrieular heart rate, but heart rate reduction is significantly higher in diltiazem group, thus should be considered as a drug of choice for emergency control of ventrieular rate. Under clinical monitoring this dose of diltiazem seems to be safe and applicable in AF patients with congestive heart failure. Both drugs have no effect on PA and HV intervals but increase the AH interval thereby can reduce ventricular rate. 展开更多
关键词 Afrial fibrillation Atrioventricular conduction system Ventricular rate
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基于optisystem的光纤通信系统的仿真与分析
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作者 陆锋 何秀芳 +3 位作者 卢聪燕 侯豪 李星智 陈育秀 《山西电子技术》 2025年第6期78-80,共3页
运用OptiSystem仿真软件设计了一个光纤通信系统,对系统中各个部件的参数进行了调节,对比不同结构与参量下系统的信号传输效果。分别针对传输距离、信号传输速率、信号波长、调制方式和光电探测器类型,采用眼图观测器和系统误码率观测器... 运用OptiSystem仿真软件设计了一个光纤通信系统,对系统中各个部件的参数进行了调节,对比不同结构与参量下系统的信号传输效果。分别针对传输距离、信号传输速率、信号波长、调制方式和光电探测器类型,采用眼图观测器和系统误码率观测器,对系统性能进行了评估,结果表明对设计和优化光纤通信系统,提高系统的传输性能和可靠性具有重要的指导意义。 展开更多
关键词 光纤通信系统 OPTIsystem 眼图 误码率 Q因子
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基于L-System与遗传算法的光线仿生采集在建筑设计中的应用研究
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作者 闵睿熙 张永 刘力 《贵阳学院学报(自然科学版)》 2025年第2期75-78,共4页
基于林登麦伊尔系统与遗传算法的光线仿生采集模型,通过模拟自然界中生物对光的利用方式,以此模拟采光效果。结果显示,所提模型可以看出不同时间段和不同测点的采光强度变化。晴天采光时14∶00至16∶00期间,5个测点的采光强度较高。阴... 基于林登麦伊尔系统与遗传算法的光线仿生采集模型,通过模拟自然界中生物对光的利用方式,以此模拟采光效果。结果显示,所提模型可以看出不同时间段和不同测点的采光强度变化。晴天采光时14∶00至16∶00期间,5个测点的采光强度较高。阴天的采光强度集中于12∶00至14∶00,其余时间采集的太阳强度相对较少,不利于采光。这说明,所提模型能够有效地预测建筑内不同区域的采光强度,并针对不同天气对光照条件进行合理利用。 展开更多
关键词 L-system 遗传算法 光线仿生采集 建筑光照优化
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System Xc-/GSH/GPX4通路介导铁死亡在消化道肿瘤耐药中的研究进展 被引量:1
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作者 李星霓 王潇 赵贵君 《河北医药》 2025年第4期663-667,共5页
获得性耐药是降低消化道肿瘤治疗疗效,引起肿瘤复发甚至死亡的主要原因,也是消化道肿瘤治疗的主要挑战。System Xc-/GSH/GPX4通路介导铁死亡与消化道肿瘤耐药性密切相关。了解System Xc/GSH/GPX4的结构和功能,探讨System Xc-/GSH/GPX4... 获得性耐药是降低消化道肿瘤治疗疗效,引起肿瘤复发甚至死亡的主要原因,也是消化道肿瘤治疗的主要挑战。System Xc-/GSH/GPX4通路介导铁死亡与消化道肿瘤耐药性密切相关。了解System Xc/GSH/GPX4的结构和功能,探讨System Xc-/GSH/GPX4通路在消化道肿瘤耐药中的作用,对于靶向System Xc-/GSH/GPX4通路及其相关调控因子,诱导铁死亡,克服肿瘤耐药性,提高肿瘤治疗疗效具有重要意义。本文通过阐述system Xc/GSH/GPX4的结构和功能,探讨System Xc-/GSH/GPX4通路在消化道肿瘤耐药中的作用,为进一步深入消化道肿瘤治疗提供新的思路及方向。 展开更多
关键词 system Xc-/GSH/GPX4 活性氧 铁死亡 消化道肿瘤 耐药
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miR-153-3p通过调控Nrf2/System Xc-分子轴抑制低氧诱导的滋养细胞铁死亡
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作者 阳双健 唐玲玲 《华中科技大学学报(医学版)》 北大核心 2025年第6期772-780,共9页
目的 探讨下调miR-153-3p对低氧诱导下滋养细胞铁死亡的影响及作用机制。方法 采用qRT-PCR检测子痫前期(PE)患者和正常孕妇胎盘组织中miR-153-3p及铁死亡相关基因mRNA表达水平。以人绒毛膜滋养层细胞株HTR-8/SVneo作为研究对象,将miR-15... 目的 探讨下调miR-153-3p对低氧诱导下滋养细胞铁死亡的影响及作用机制。方法 采用qRT-PCR检测子痫前期(PE)患者和正常孕妇胎盘组织中miR-153-3p及铁死亡相关基因mRNA表达水平。以人绒毛膜滋养层细胞株HTR-8/SVneo作为研究对象,将miR-153-3p inhibitor及其阴性对照inhibitor-NC与si-核因子E2相关因子2(Nrf2)及其阴性对照si-NC分别转染至HTR-8/SVneo细胞中,并在常氧(Nor)或低氧(Hyp)条件下培养48 h, CCK-8检测细胞增殖活性;qRT-PCR检测细胞中miR-153-3p及Nrf2 mRNA表达水平;DCFH-DA探针法检测细胞中活性氧(ROS)水平;比色法检测细胞中丙二醛(MDA)含量及超氧化物歧化酶(SOD)、谷胱甘肽(GSH)活性水平;亚铁离子检测试剂盒检测细胞中Fe2+水平;试剂盒法检测细胞中胱氨酸(Cys)及细胞上清液中谷氨酸(Glu)水平;Western blot检测细胞中Nrf2/System Xc-分子轴相关蛋白Nrf2、GPX4、SLC7A11表达水平;双荧光素酶报告基因实验验证miR-153-3p与Nrf2之间的靶向调控关系。结果 与正常孕妇比较,PE患者胎盘组织中miR-153-3p及铁死亡激活基因COX2、ACSL4、NOX1等mRNA表达升高,而铁死亡抑制基因GPX4、SLC7A11、SLC3A2、FTH1等mRNA表达降低(均P<0.05)。随着低氧诱导的时间延长,HTR-8/SVneo细胞增殖活性逐渐降低,细胞中miR-153-3p表达水平以及ROS、MDA和Fe2+水平升高(均P<0.05),而SOD、GSH和Cys水平以及上清液中Glu水平降低(均P<0.05),同时细胞中铁死亡相关蛋白GPX4、SLC7A11表达降低(均P<0.05)。下调miR-153-3p可降低低氧诱导下HTR-8/SVneo细胞中的ROS、MDA和Fe2+水平(均P<0.05),促进细胞中SOD和GSH活性水平升高,上调细胞中Cys水平和细胞上清液中Glu水平,同时促进铁死亡相关蛋白GPX4、SLC7A11表达(均P<0.05)。双荧光素酶报告基因实验证实Nrf2是miR-153-3p的下游靶基因,而沉默Nrf2可逆转下调miR-153-3p对低氧诱导下HTR-8/SVneo细胞铁死亡的抑制作用。结论 下调miR-153-3p可抑制低氧诱导下的人滋养细胞HTR-8/SVneo铁死亡,其机制可能与靶向Nrf2调控Nrf2/System Xc-分子轴有关。 展开更多
关键词 滋养细胞 低氧 miR-153-3p 铁死亡 Nrf2/system Xc-轴
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Optimal Planning of Multiple PV-DG in Radial Distribution Systems Using Loss Sensitivity Analysis and Genetic Algorithm
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作者 A. Elkholy 《Journal of Power and Energy Engineering》 2025年第2期1-22,共22页
This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity fa... This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity factor (LSF), genetic algorithms (GA) methods, and numerical method based on LSF. The methodology aims to determine the optimal allocation and sizing of multiple PV-DG to minimize power loss through time series power flow analysis. An approach utilizing continuous sensitivity analysis is developed and inherently leverages power flow and loss equations to compute LSF of all buses in the system towards employing a dynamic PV-DG model for more accurate results. The algorithm uses a numerical grid search method to optimize PV-DG placement in a power distribution system, focusing on minimizing system losses. It combines iterative analysis, sensitivity assessment, and comprehensive visualization to identify and present the optimal PV-DG configurations. The present-ed algorithms are verified through co-simulation framework combining MATLAB and OpenDSS to carry out analysis for 12-bus radial distribution test system. The proposed numerical method is compared with other algorithms, such as ELF, LSF methods, and Genetic Algorithms (GA). Results show that the proposed numerical method performs well in comparison with LSF and ELF solutions. 展开更多
关键词 Photovoltaic systems Distributed Generation Multiple Allocation and Sizing Power Losses Radial Distribution system Genetic Algorithm
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Architecture to Secure Electrical Control System in Cyber-Physical System
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作者 Depeng Li 《Journal of Information Security》 2025年第1期149-157,共9页
It’s possible for malicious operators to seize hold of electrical control systems, for instance, the engine control unit of driverless vehicles, from various vectors, e.g. autonomic control system, remote vehicle acc... It’s possible for malicious operators to seize hold of electrical control systems, for instance, the engine control unit of driverless vehicles, from various vectors, e.g. autonomic control system, remote vehicle access, or human drivers. To mitigate potential risks, this paper provides the inauguration study by proposing a theoretical framework in the physical, human and cyber triad. Its goal is to, at each time point, detect adversary control behaviors and protect control systems against malicious operations via integrating a variety of methods. This paper only proposes a theoretical framework which tries to indicate possible threats. With the support of the framework, the security system can lightly reduce the risk. The development and implementation of the system are out of scope. 展开更多
关键词 ARCHITECTURE Control system FRAMEWORK
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Construction and Application of University Welcome System under the Background of Informatization
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作者 Rong Su 《Journal of Software Engineering and Applications》 2025年第2期67-75,共9页
The rapid advancement of information technology has promoted the development of informatization in universities. The freshmen welcome information system of universities is the first important system to showcase the di... The rapid advancement of information technology has promoted the development of informatization in universities. The freshmen welcome information system of universities is the first important system to showcase the digital level of the university to new students. With the expansion of the enrollment scale of universities, improving the efficiency of welcoming work has become an urgent problem to be solved. This article analyzes the characteristics and existing problems of the welcoming work, combined with the main technical methods of information system construction, and based on the comprehensive situation of information systems in our university, proposes the construction goals and ideas of the welcoming information system, summarizes the construction process and operation results of the welcome system, and explores possible directions for future optimization. 展开更多
关键词 Welcome system INFORMATIZATION UNIVERSITY Digital Campus REGISTRATION
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Reinforcement Learning in Mechatronic Systems: A Case Study on DC Motor Control
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作者 Alexander Nüßgen Alexander Lerch +5 位作者 René Degen Marcus Irmer Martin de Fries Fabian Richter Cecilia Boström Margot Ruschitzka 《Circuits and Systems》 2025年第1期1-24,共24页
The integration of artificial intelligence into the development and production of mechatronic products offers a substantial opportunity to enhance efficiency, adaptability, and system performance. This paper examines ... The integration of artificial intelligence into the development and production of mechatronic products offers a substantial opportunity to enhance efficiency, adaptability, and system performance. This paper examines the utilization of reinforcement learning as a control strategy, with a particular focus on its deployment in pivotal stages of the product development lifecycle, specifically between system architecture and system integration and verification. A controller based on reinforcement learning was developed and evaluated in comparison to traditional proportional-integral controllers in dynamic and fault-prone environments. The results illustrate the superior adaptability, stability, and optimization potential of the reinforcement learning approach, particularly in addressing dynamic disturbances and ensuring robust performance. The study illustrates how reinforcement learning can facilitate the transition from conceptual design to implementation by automating optimization processes, enabling interface automation, and enhancing system-level testing. Based on the aforementioned findings, this paper presents future directions for research, which include the integration of domain-specific knowledge into the reinforcement learning process and the validation of this process in real-world environments. The results underscore the potential of artificial intelligence-driven methodologies to revolutionize the design and deployment of intelligent mechatronic systems. 展开更多
关键词 Artificial Intelligence in Product Development Mechatronic systems Reinforcement Learning for Control system Integration and Verification Adaptive Optimization Processes Knowledge-Based Engineering
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Multi-Factor Authentication for Keyless Entry Systems: An Innovative Approach to Automotive Security
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作者 Danilo Brito Shakour Abuzneid 《Journal of Information Security》 2025年第1期78-100,共23页
Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more s... Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more susceptible to appealing attacks like relay attacks and critical fob hacking. These weaknesses present considerable security threats, resulting in unauthorized entry and car theft. The suggested approach combines a conventional keyless entry feature with an extra security measure. Implementing multi-factor authentication significantly improves the security of systems that allow keyless entry by reducing the likelihood of unauthorized access. Research shows that the benefits of using two-factor authentication, such as a substantial increase in security, far outweigh any minor drawbacks. 展开更多
关键词 MFA Keyless Entry systems Automotive Security Biometric Authentication
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无机纳米材料-微生物杂合系统的研究进展
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作者 宋浩 张妍 刘其敬 《天津大学学报(自然科学与工程技术版)》 北大核心 2026年第1期1-16,共16页
随着CO_(2)排放问题日益严峻,有效减少碳排放是目前最受关注的热点问题.通过物理封存和化学转化等技术固定CO_(2)能耗大且安全性有待评估,而微生物固定CO_(2)技术凭借其环境友好成为可持续碳捕集方案之一.天然固碳微生物通过卡尔文循环... 随着CO_(2)排放问题日益严峻,有效减少碳排放是目前最受关注的热点问题.通过物理封存和化学转化等技术固定CO_(2)能耗大且安全性有待评估,而微生物固定CO_(2)技术凭借其环境友好成为可持续碳捕集方案之一.天然固碳微生物通过卡尔文循环等7种途径固定CO_(2),然而这些途径的固碳效率仍然面临能量供给不足、关键酶催化效率低等问题,限制了其在工业化碳捕集和转化中的广泛应用.一方面,通过合成生物学和代谢工程等方法可以优化光合自养微生物、化能自养微生物和异养微生物的固碳效率,并将CO_(2)高效转化为多种高值化学品.另一方面,无机纳米材料-微生物杂合系统将半导体纳米材料与微生物结合,利用材料优良的光-电转化性能不仅可以增强光能的捕获和电子传递效率,同时能够显著提升CO_(2)转化为高值化学品的效率.本综述总结了微生物天然固定CO_(2)的7种途径,阐述了光合自养、化能自养和异养微生物固碳途径优化机制的近期进展.同时,总结了这些工程细胞及材料-细胞杂合体系统的设计构建技术,分别介绍了直接电子传递下的无机纳米材料-微生物杂合系统和电子载体介导下的无机纳米材料-微生物杂合系统的重要应用,阐述了纳米材料在固定CO_(2)过程中的关键作用和原理,并展望了该领域的未来发展趋势. 展开更多
关键词 二氧化碳捕集 微生物 合成生物学 杂合系统
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丘陵山地履带式玉米收获机线控系统设计与试验
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作者 徐峰 李玲玲 +3 位作者 王华泽 高瑞遥 张磊 周思路 《中国农机化学报》 北大核心 2026年第1期241-245,265,共6页
为提高丘陵山地履带式玉米收获机的工作效率及智能化工作水平,基于CAN总线设计一种履带式玉米收获机线控系统。在阐述整机工作原理的基础上设计整机液压系统;为提高系统可靠性,选用C420行走机械专用控制器作为ECU控制单元,设计线控系统... 为提高丘陵山地履带式玉米收获机的工作效率及智能化工作水平,基于CAN总线设计一种履带式玉米收获机线控系统。在阐述整机工作原理的基础上设计整机液压系统;为提高系统可靠性,选用C420行走机械专用控制器作为ECU控制单元,设计线控系统硬件电路;基于CODESYS软件编写行走速度控制程序,并结合人机交互模式实现对机器行进速度和工作部件动作的驱动控制。通过田间试验对控制系统的应用进行测试,结果表明:履带式玉米收获机的实际最高行驶速度为11.24 km/h,3个挡位均可平稳、快速地实现无级变速;丘陵山地履带式玉米收获机线控系统可以在田间正常工作,控制系统响应速度较快、稳定性好,可以满足玉米收获及行进速度稳定的要求。 展开更多
关键词 履带式玉米收获机 静液压传动装置 液压系统 线控系统 性能试验
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Analysis of Two Irrigation Water Pumping Systems on the Taddis Valley Site: Solar Kit and Motor Pump Unit (GMP) in Tahoua (Niger)
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作者 Yerima Bako Djibo Aboubacar Guero Yadji Bori Haoua 《World Journal of Engineering and Technology》 2025年第1期39-48,共10页
The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this stud... The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this study is to carry out a comparative analysis of two dewatering pumping systems (Solar Kit and GMP) for water mobilization on a certain number of criteria such as sustainable use, economic aspect and performance. To achieve this, the adapted methodology consisted first of all in the development of a data collection tool in the field. Then flow measurements, estimation of fuel consumption, pressure height, etc., were carried out. Thus, the data collection involved a sample of 120 irrigators who had to use the two (2) types of pumping systems. The collected data were analyzed and processed with appropriate software. The results of the study show that the two pumping systems studied have strengths and constraints. Thus, the solar pumping system has a significant investment cost, very low maintenance and a low operating cost. On the other hand, the system with a generator has a relatively low investment cost (25 to 30 times less than solar), but a relatively high operating, upkeep and maintenance cost. He adds that these assets and constraints must be taken into consideration when an investment is made. This study shows that 74% of producers use GMP compared to 26% who use the Solar Kit. But in practice, the Solar Kit is more reliable for producers from the point of view of planted area, environmental management and investment costs, supply of fuel and lubricant. These results indicate better performance of the solar pumping system compared to GMP at the study sites. 展开更多
关键词 Market Gardening Sites Pumping systems Solar Kit GMP Taddis and Tahoua Valley
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公立医院薪酬制度改革政策研究:中央顶层设计与地方制度响应
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作者 申思 庞朝玮 +4 位作者 王萧冉 邢丝雨 王晨雨 李卓婷 唐蔚蔚 《中国医院》 北大核心 2026年第1期12-15,共4页
公立医院薪酬制度改革是深化医改的关键环节,直接影响医务人员激励水平、医疗资源配置与服务效能。笔者梳理近10年内国家层面的政策演进脉络,聚焦改革从试点探索到系统部署、再到机制完善的阶段特征,并选取三明、台州、重庆、石家庄等... 公立医院薪酬制度改革是深化医改的关键环节,直接影响医务人员激励水平、医疗资源配置与服务效能。笔者梳理近10年内国家层面的政策演进脉络,聚焦改革从试点探索到系统部署、再到机制完善的阶段特征,并选取三明、台州、重庆、石家庄等地为典型案例,分析其在制度设计、实施路径与配套改革方面的实践经验。研究表明,改革呈现出“政策引领-地方试点-机制协同-体系延伸”的演化趋势,逐步推动医保、财政、人事等制度协同发力,构建更具激励性、规范性与可持续性的薪酬体系。 展开更多
关键词 医院薪酬 薪酬制度 公立医院 医疗改革 绩效考核
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基于药物纳米晶的肿瘤靶向纳米递药系统研究进展
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作者 吕春艳 信文婧 +6 位作者 崔闻宇 申光焕 张文君 韩锐 王文倩 厚晓庆 周浦诺 《医药导报》 北大核心 2026年第1期100-108,共9页
药物纳米晶粒径小,比表面积大,可以改善难溶性药物的溶解度问题,提高药物的生物利用度。对药物纳米晶进行表面修饰,可以实现对特定位点的靶向,延长药物在体内的循环时间,增强细胞摄取和肿瘤抑制作用,降低对正常组织的毒副作用,对靶组织... 药物纳米晶粒径小,比表面积大,可以改善难溶性药物的溶解度问题,提高药物的生物利用度。对药物纳米晶进行表面修饰,可以实现对特定位点的靶向,延长药物在体内的循环时间,增强细胞摄取和肿瘤抑制作用,降低对正常组织的毒副作用,对靶组织发挥治疗作用。该文系统地综述了药物纳米晶的制备技术及在肿瘤治疗中的4种靶向系统,并对其在肿瘤治疗领域的发展与应用前景进行展望,为药物纳米晶的进一步研究提供参考。 展开更多
关键词 药物纳米晶 肿瘤靶向 纳米递药系统 表面修饰 制备技术
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Effectiveness of Logistics Management Information System (LMIS) in Improving the Availability of Essential Medicines and Medical Supplies in Public Hospitals in Zambia: A Cross-Sectional Study
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作者 Aubrey Kanyika Steward Mudenda +4 位作者 Victor Daka Nayuda Kaonga Chitundu Mbao Diana K. Mwaba Scott Kaba Matafwali 《Pharmacology & Pharmacy》 2025年第2期61-72,共12页
Background: The availability of essential medicines and medical supplies is crucial for effectively delivering healthcare services. In Zambia, the Logistics Management Information System (LMIS) is a key tool for manag... Background: The availability of essential medicines and medical supplies is crucial for effectively delivering healthcare services. In Zambia, the Logistics Management Information System (LMIS) is a key tool for managing the supply chain of these commodities. This study aimed to evaluate the effectiveness of LMIS in ensuring the availability of essential medicines and medical supplies in public hospitals in the Copperbelt Province of Zambia. Materials and Methods: From February to April 2022, a cross-sectional study was conducted in 12 public hospitals across the Copperbelt Province. Data were collected using structured questionnaires, checklists, and stock control cards. The study assessed LMIS availability, training, and knowledge among pharmacy personnel, as well as data accuracy, product availability, and order fill rates. Descriptive statistics were used to analyse the data. Results: All surveyed hospitals had LMIS implemented and were using eLMIS as the primary LMIS. Only 47% and 48% of pharmacy personnel received training in eLMIS and Essential Medicines Logistics Improvement Program (EMLIP), respectively. Most personnel demonstrated good knowledge of LMIS, with 77.7% able to log in to eLMIS Facility Edition, 76.6% able to locate stock control cards in the system, and 78.7% able to perform transactions. However, data accuracy from physical and electronic records varied from 0% to 60%, and product availability ranged from 50% to 80%. Order fill rates from Zambia Medicines and Medical Supplies Agency (ZAMMSA) were consistently below 30%. Discrepancies were observed between physical stock counts and eLMIS records. Conclusion: This study found that most hospitals in the Copperbelt Province of Zambia have implemented LMIS use. While LMIS implementation is high in the Copperbelt Province of Zambia, challenges such as low training levels, data inaccuracies, low product availability, and order fill rates persist. Addressing these issues requires a comprehensive approach, including capacity building, data quality improvement, supply chain coordination, and investment in infrastructure and human resources. Strengthening LMIS effectiveness is crucial for improving healthcare delivery and patient outcomes in Zambia. 展开更多
关键词 Logistics Management Information system Essential Medicines Medical Supplies Supply Chain Management Zambia
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