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Miniature magnetically anchored and controlled camera system for trocar-less laparoscopy

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World Journal of Gastroenterology 2017年第12期23卷 2168-2174页

作者： ding-hui dong hao-yang zhu yu luo hong-ke zhang jun-xi xiang fei xue rong-qian wu yi lv Department of Hepatobiliary Surgery First Affiliated Hospital Xi’an Jiaotong University

AIM To design a miniature magnetically anchored and controlled camera system to reduce the number of trocars which are required for *** The system consists of a miniature magnetically anchored camera with a 30° downward angle, an external magnetically anchored unit, and a vision output device. The camera weighs 12 g, measures Φ10.5 mm × 55 mm and has two magnets, a vision model, a light source, and a metal hexagonal nut. To test the prototype, the camera was inserted through a 12-mm conventional trocar in an ex vivo real liver laparoscopic training system. A trocar-less laparoscopic cholecystectomy was performed 6 times using a 12-mm and a 5-mm conventional trocar. In addition, the same procedure was performed in four canine *** Both procedures were successfully performed using only two conventional laparoscopic trocars. The cholecystectomy was completed without any major complication in 42 min(38-45 min) in vitro and in 50 min(45-53 min) using an animal model. This camera was anchored and controlled by an external unit magnetically anchored on the abdominal wall. The camera could generate excellent image. with no instrument *** The camera system we designed provides excellent optics and can be easily maneuvered. The number of conventional trocars is reduced without adding technical difficulties.

关键词： Trocar-less laparoscopy Magnetically anchored and controlled camera Minimally invasive surgery

Characteristics of fecal microbial communities in patients with non-anastomotic biliary strictures after liver transplantation

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World Journal of Gastroenterology 2017年第46期23卷 8217-8226页

作者： Jing Zhang Feng-gang Ren Peng Liu Hong-ke Zhang hao-yang zhu Zhe Feng Xu-Feng Zhang Bo Wang Xue-ming Liu Xiao-gang Zhang Rong-qian Wu Yi Lv Department of Hepatobiliary Surgery First Affiliated Hospital of Xi’an Jiaotong University Institute of Advanced Surgical Technology and Engineering First Affiliated Hospital of Xi’an Jiaotong University Shaanxi Provincial Center for Regenerative Medicine and Surgical Engineering First Affiliated Hospital of Xi’an Jiaotong University

AIM To explore the possible relationship between fecal microbial communities and non-anastomotic stricture(NAS) after liver transplantation(LT).METHODS A total of 30 subjects including 10 patients with NAS, 10 patients with no complications after LT, and 10 nonLT healthy individuals were enrolled. Fecal microbial communities were assessed by the 16 S r RNA gene sequencing *** Different from the uncomplicated and healthy groups, unbalanced fecal bacterium ratio existed in patients with NAS after LT. The results showed that NAS patients were associated with a decrease of Firmicutes and Bacteroidetes and an increase of Proteobacteria at the phylum level, with the proportion-ratio imbalance between potential pathogenic families including Enterococcaceae, Streptococcaceae, Enterobacteriaceae, Pseudomonadaceae and dominant families including Bacteroidaceae. CONCLUSION The compositional shifts of the increase of potential pathogenic bacteria as well as the decrease of dominant bacteria might contribute to the incidence of NAS.

关键词： Non-anastomotic stricture Orthotopic liver transplantation Fecal microbiota Dysbacteriosis Ischemia-reperfusion injury

Conformational Studies of β2,3-Cyclic Aminoxy Peptides in Protic Solvents

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Conformational Studies of β2,3-Cyclic Aminoxy Peptides in P...

中国化学会第四届有机化学学术会议

作者： hao, Yu yang, Dan zhu, Nian-Yong (Department of Chemistry, the University of Hong Kong, Pokfulam Road, Hong Kong)

＜正＞Our group has reported that one novel type of foldamers, aminoxy peptides, can adopt a unique secondary structure, N-O turn, which is very stable and rigid in solid states and nonpolar solvents, i.e. CDCl3 or CD2Cl2. It is spontaneous for us to investigate whether our aminoxy peptides still can maintain any secondary structures in polar solvent or even in buffer which is similar to the biological environment. Compounds 1, which is derived from trans-4-aminooxy-3-carboxy-piperidinium （trans-AOCP）, and 2, derived from cis-4-aminooxy-3-carboxy-

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苯和甲醇烷基化反应机理及催化剂研究进展

现代化工 2017年第1期37卷 41-44,46页

作者：闻振浩杨大强朱学栋华东理工大学工业大型反应器工程教育部工程研究中心上海200237 华东理工大学化学工程联合国家重点实验室上海200237

对近年来国内在苯和甲醇烷基化研究取得的进展进行了综述。介绍了苯和甲醇烷基化机理,总结了国内在苯和甲醇烷基化催化剂开发取得的进展,并讨论了苯和甲醇烷基化反应的影响因素。ZSM-5分子筛是催化苯和甲醇烷基化反应的适宜载体,通过适... 详细信息

对近年来国内在苯和甲醇烷基化研究取得的进展进行了综述。介绍了苯和甲醇烷基化机理,总结了国内在苯和甲醇烷基化催化剂开发取得的进展,并讨论了苯和甲醇烷基化反应的影响因素。ZSM-5分子筛是催化苯和甲醇烷基化反应的适宜载体,通过适当改性可以提高其催化性能。苯和甲醇烷基化催化剂已完成吨级放大,现已进入工业试验阶段。

关键词：苯甲醇烷基化二甲苯

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng zhu Cun Liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

EKF在SINS/GNSS深组合导航中的应用

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现代防御技术 2017年第5期45卷 53-62页

作者：连文浩杨小龙朱磊程帅中国人民解放军63981部队湖北武汉430311

为了在卫星较少条件下也能提供连续稳定、精度高的导航,建立了一种基于扩展卡尔曼滤波器(extended Kalman filter,EKF)的捷联惯导系统(strapdown inertial navigation system,SINS)/全球导航卫星系统(global navigation satellite system,GNSS)深组合导航系统,并对该系统所采用的导航结构、状态估计算法等进行研究设计。最后,在战术级条件下,分别对单独的SINS,SINS/GNSS松组合导航系统和SINS/GNSS深组合导航系统进行仿真验证,并对导航结果进行对比分析。从仿真结果可以看出,深组合导航系统位置误差约为0.3 m,速度误差约为0.01 m/s,姿态误差约为0.005°。对比分析可知深组合导航精度更高,且不受卫星个数条件影响,具有很高的实用价值。

关键词： SINS/GNSS深组合导航扩展卡尔曼滤波状态估计导航精度导航定位结果战术级

Nanoparticles for the treatment of spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1665-1680页

作者： Qiwei yang Di Lu Jiuping Wu Fuming Liang Huayi Wang Junjie yang Ganggang Zhang Chen Wang Yanlian yang Ling zhu Xinzhi Sun Department of Orthopedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Neurosurgery The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

关键词： antioxidants axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases neuroprotection spinal cord injury stem cells

Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期 284-293页

作者： Xuemei yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling zhu Chengjun Ji Biao zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao Hang Ma Conghui Zhang Yongxin yang Shuyuan Yu Haiye zhu Yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery