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Asymmetric synthesis of L-carnitine from (R)-3-chloro-1,2-propanediol

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Chinese Chemical Letters 2011年第7期22卷 765-767页

作者： Xu Qin Li Yun Xu Yang Wei Li Wang Bin Hu Hui Min xue Tian yi zhang xue Tao zhang Department of Chemistry University of Science and Technology Beijing Beijing 100083 China

A practical chemical synthesis of L-camitine （1） has been accomplished from （R）-3-chloro-1,2-propanediol （（R）-4）, which is a main by-product originated from （R,R）-Salen Co（III） catalyzed hydrolytic kinetic resolution （HKR） of （±）-epichlorohydrin. （R）-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite （（R）-S）. The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds.

关键词： L-Camitine Cyclic sulfite (R)-3-Chloro-1,2-propanediol

The ORF3a protein of SARS-CoV-2 induces apoptosis in cells

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Cellular & Molecular Immunology 2020年第8期17卷 881-883页

作者： Yujie Ren Ting Shu Di Wu Jingfang Mu Chong Wang Muhan Huang Yang Han xue-yi zhang Wei Zhou Yang Qiu Xi Zhou Center for Precision Translational Medicine of Wuhan Institute of Virology&Guangzhou Women and Children’s Medical Center Guangzhou Women and Children’s Medical CenterGuangzhouGuangdong510120China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of Sciences(CAS)WuhanHubei430071China Center for Precision Translational Medicine of Wuhan Institute of Virology&Guangzhou Women and Children’s Medical Center Wuhan Institute of VirologyCASWuhanHubei430071China Joint Laboratory of Infectious Diseases and Health Wuhan Institute of Virology&Wuhan Jinyintan HospitalCASWuhanHubei430023China Center for Translational Medicine Wuhan Jinyintan HospitalWuhanHubei430023China State Key Laboratory of Virology College of Life SciencesWuhan UniversityWuhanHubei430072China University of Chinese Academy of Sciences Beijing100049China

Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)has caused the ongoing pandemic of Coronavirus Disease ***-CoV-2 belongs to the genus Betacoronavirus of the Coronaviridae family,which includes SARS-CoV and Middle East respiratory syndrome coronavirus.1,2 Coronavirus-encoded accessory proteins play critical roles in virus–host interactions and the modulation of host immune responses,thereby contributing to coronaviral pathogenicity via different strategies.3 However,the functions of SARS-CoV-2-encoded accessory proteins are not well *** is a predominant type of programmed cell death,and has been recognized as an important host antiviral defense mechanism that controls viral infection and regulates the inflammatory response.4,5 Previous studies have reported that the SARS-CoV-encoded accessory protein ORF3a can induce apoptosis in cells,6,7 leading to the question of whether SARS-CoV-2 ORF3a also has pro-apoptotic ***,we investigated the potential apoptosis-inducing activity of SARS-CoV-2 ORF3a in different cell lines and compared the pro-apoptotic activities of SARS-CoV-2 ORF3a with those of SARS-CoV ORF3a using the same system.

关键词： respiratory acute thereby

Template Effect on Structure and Morphology of Ni(OH)_2 Powders Prepared by Hydro chemical Method

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Journal of Central South University 2000年第1期12卷 20-24页

作者： LIU Zhi hong,LI Qi hou,XU Xiao lin,GUO xue yi,zhang Duo mo (Department of Metallurgical Science and Engineering, Central South University of Technology, Changsha 410083, China) Department of Metallurgical Science and Engineering Central South University of Technology Changsha China

The template effect controlling the structure and morphology of ultrafine particles was described. Ni(OH) 2 powders were prepared by NH 3 coordination precipitation method. The effects of SO 2- 4, NO - 3, Cl -, NH 3, pH value on Ni(OH) 2 structure and morphology were investigated experimentally, explained with the theoretical model that the growth units were the polyhedral structure of coordination anions. The results showed that the structure and morphology of Ni(OH) 2 were effectively controlled by the growth units, the dimensions and the linking patterns of the growth units vary with the changes of physical and chemical conditions in the aqueous solution.

关键词： Ni(OH)_2 structural control polyhedral structure of coordination anions growth units

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou ying Xiaoli Si Naijia xue yi Liu Ran Zheng ying Chen Jiali Pu Baorong zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie zhang Cancan WU Yuting zhang yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

Comparison of FP-7 and S-2 Ahmed glaucoma valve implantation in refractory glaucoma patients for short-term follow-up

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Chinese Medical Journal 2011年第8期124卷 1128-1133页

作者： BAI Yu-jing LI yi-qing CHAI Fang YANG xue-jiao zhang yi-chong WEI Yan-tao HUANG Jing-jing GE Jian ZHUO Ye-hong State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou Guangdong 510060 China

Background Ahmed glaucoma valves （AGV） has been used for decades, but there is no detailed report about the efficacy of AGV in Chinese glaucoma patients. This study aimed to compare the intraocular pressure （IOP） lowering efficacy and side effects of S-2 polypropylene and PF-7 silicone AGV implantation in Chinese refractory glaucoma *** Patients were divided into S-2 model AGV group and FP-7 model AGV group. The complete and qualified surgical success rate, change of IOP, number of anti-glaucoma medications used and postoperative complications were recorded and *** Average follow-up time was comparable between two groups. IOP was reduced from （37.9±12.7） mmHg preoperatively to （17.3±5.3） mmHg at the last follow-up in S-2 group and reduced from （39.9±14.4） mmHg to （17.7±4.9）mmHg in FP-7 group. Anti-glaucoma medications were reduced from 3.8±0.2 to 1.5±0.2 in S-2 group, and 3.5±0.2 to 0.7±0.2 in FP-7 groups. The cumulative success rates were comparable in two groups, which were 61.2% and 72.1% in S-2 group and FP-7 group respectively. When IOP reduction criteria was used, complete success rates were 30.6% and 51.2% for S-2 and FP-7 groups, and qualified success rates were 86.1% and 92.7% separately. In both groups, the major complication was hypotony, and the previous trabeculectomy of patients was the major risk factor for surgery *** In this short-term retrospective study, S-2 AGV is showed at least as effective as FP-7 AGV in IOP reduction, but associated with higher rate of complications. Previous trabeculectomy is a principle risk factor for AGV implantation failure. These clinical outcomes are important for converting use of the FP-7 silicon AGV in Chinese refractory glaucoma patients.

关键词： glaucoma, drainage device Ahmed refractor glaucoma

基于贝叶斯神经网络的近红外光谱实木地板表面缺陷检测

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光谱学与光谱分析 2017年第7期37卷 2041-2045页

作者：梁浩曹军林雪张怡卓东北林业大学机电工程学院黑龙江哈尔滨150040 东北林业大学材料科学与工程学院黑龙江哈尔滨150040

实木地板的表面缺陷直接影响其力学性能和产品等级,表面缺陷的快速检测对实木地板的在线分选具有重要的现实意义。针对视觉方法检测实木地板表面缺陷识别率低的问题,提出了一种基于近红外光谱分析技术的检测方法。首先,分别采集规格为20... 详细信息

实木地板的表面缺陷直接影响其力学性能和产品等级,表面缺陷的快速检测对实木地板的在线分选具有重要的现实意义。针对视觉方法检测实木地板表面缺陷识别率低的问题,提出了一种基于近红外光谱分析技术的检测方法。首先,分别采集规格为200mm×100mm×20mm的表面带有活节、死节以及无缺陷的实木地板的光谱数据各60份,其中30份作为训练样本,30份作为测试样本;其次,使用高斯滤波(GSF)、分段多元散射校正(PMSC)和去趋势法(DT)等方法对采集到的光谱数据进行预处理,降低光谱噪声、消除光谱的散射影响;然后,利用改进遗传算法从处理后的光谱中提取特征波长用于构建缺陷识别与分类模型;最后,使用基于贝叶斯理论改进的神经网络构建实木地板缺陷识别和分类模型。实验使用含有活节、死节以及无缺陷的实木地板样本对模型进行训练和测试,结果表明:通过贝叶斯神经网络构建的缺陷识别与分类模型能够准确识别活节、死节和无缺陷三类实木地板,识别率分别为92.20%,94.47%和95.57%。证明了实木地板表面缺陷类型与其近红外吸收光谱密切相关,并为下一步实现实木地板表面缺陷的准确定位提供快速检测方法。

关键词：近红外光谱实木地板分段多元散射校正改进遗传算法贝叶斯神经网络

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan zhang yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Prolonged course of Paxlovid administration in a centenarian with COVID-19:A case report

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World Journal of Radiology 2024年第9期16卷 489-496页

作者： yi-xue zhang Juan Tang Dan Zhu Chun-Yan Wu Mei-Lan Liang Yuan-Tao Huang Department of Healthcare Haikou Affiliated Hospital of Central South University Xiangya School of MedicineHaikou 570208Hainan ProvinceChina Department of Healthcare Hainan Chengmei HospitalHaikou 570000Hainan ProvinceChina

BACKGROUND According to the population statistics in 2023,there were 110000 people aged over 100 years in China,and the experience of using Paxlovid(nirmatrelvir/ritonavir)for centenarians is particularly *** article reports our experience of using Paxlovid in a centenarian with the novel coronavirus disease 2019(COVID-19)*** SUMMARY A 103-year-old female with mild COVID-19 and renal insufficiency was given sufficient Paxlovid for 2 days and a half dose for 3 *** treatment,the patient was complicated with lung infection and heart failure,and nucleic acid remained *** expert consultation,a full dose of Paxlovid was given again on the 9th day of admission for 2 days and a half dose for 3 ***,anti-heart failure and antibiotics were administered;the heart failure and pulmonary infection were ***,on the 33^(th) day of admission,nucleic acid turned negative,body temperature returned to normal,cough and sputum,fatigue,poor appetite and other symptoms basically *** patient was given Paxlovid via nasal feeding for 2 courses without deterioration of liver and kidney function,diarrhea,nausea and vomiting,myalgia,chest tightness and other side effects,and was discharged from hospital with good *** This case suggests that Paxlovid can be used cautiously in centenarians with renal insufficiency and two courses of treatment can be considered in patients with persistent positive nucleic acid.

关键词： COVID-19 Paxlovid Centenarians Renal insufficiency Heart failure Lung infection Case report