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An Enantioselective Approach to heteroatom-Containing Bicyclic Derivatives via Inverse-Electron-Demand Diels-Alder Reactions

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Chinese Journal of Chemistry 2023年第1期41卷 21-26页

作者： jun-xiong he Xu-Ge Si Qi-Tao Lu Qian-Wei Zhang Quan Cai Department of Chemistry Research Center for Molecular Recognition and Synthesis220 Handan RoadFudan UniversityShanghai 200433China

Chiral heteroatom-containing bicyclic scaffolds are important pharmacophores and prevalent in bioactive natural products and drug ***,we report a unified approach for the divergent synthesis of chiral heteroatom-containing bicyclic derivatives by lanthanide(lil)-catalyzed asymmetric inverse-electron-demand Diels-Alder reactions of *** reactions occur with vari-ous readily available dihydropyrroles and dihydrofurans as dienophiles,providing a step-economical synthetic platform for densely functionalized ciss-hydroindoles and cis-hydrobenzofurans with excellent yields and *** synthetic utility of this approach is demonstrated by the concise synthesis of(-)-α-lycorane and(-)-lycorine alkaloids.

关键词： Asymmetric catalysis heterocycles Total synthesis 2-Pyrones Inverse-electron-demand Diels-Alder reaction Cycloaddition

Low concentration of sodium hyaluronate temporarily elevates the tear film lipid layer thickness in dry eye patients with lipid deficiency

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 389-394页

作者： Yan Li Xuan Sang Liu Yang Xiao-Ran Wang Jia-Hui Liu xiong-jun he Ying Liu Xiao-he Lu Zhi-Chong Wang State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 Guangdong Province China Department of Ophthalmology Zhujiang Hospital of Southem Medical University Guangzhou 510282 Guangdong Province China

AIM： To investigate the effects of different concentrations of artificial tears on lipid layer thickness （LLT） and blink rate （BR） in dry eye patients. METHODS： This study included 106 eyes of 58 patients with dry eye. The lipid deficiency type was defined as the LLT baseline 〈75 nm. The LLT and BR were measured at baseline and 1, 5 and 15min after the instillation of 0.1% or 0.3% sodium hyaluronate （SH） eye drops by using the LipiView ocular surface interferometer. RESULTS： In the lipid deficiency group, the LLT increased from baseline at 1rain post instillation. The LLT after the instillation of 0.1% SH was significantly higher than that after the instillation of 0.3% SH （P〈0.001）. The LLT returned to baseline at 15min post instillation of 0.1% SH and at 5min post instillation of 0.3% SH. In the non-lipid deficiency group, the LLT decreased from baseline at lmin and returned to baseline at 5rain for both treatments. The BRs were not significantly different at different time points for both treatments. CONCLUSION： SH eye drops induce a short-term increase in LLT of patients with lipid deficiency. A low concentration of artificial tears have a stronger effect than a high concentration of artificial tears on the increase in LLT. in comparison, SH eye drops induce a transient and slight decrease in LLT of patients without lipid deficiency. A low concentration of artificial tears might be better for patients with lipid deficiency.

关键词： tear film lipid layer thickness dry eye artificialtears ocular surface interferometer sodium hyaluronate

Lipid layer thickness and tear meniscus height measurements for the differential diagnosis of evaporative dry eye subtypes

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International Journal of Ophthalmology(English edition) 2018年第9期11卷 1496-1502页

作者： Xuan Sang Yan Li Liu Yang Jia-Hui Liu Xiao-Ran Wang Chao-Yang Li Ying Liu Chen-Jie Wang xiong-jun he Shou-Bi Wang Zhi-Chong Wang State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina Department of Ophthalmology Zhujiang Hospital of Southem Medical UniversityGuangzhou 510060Guangdong ProvinceChina

AIM： To explore a new diagnostic index for differentiating the evaporative dry eye（EDE） subtypes by analysis of their respective clinical characteristics. METHODS： A cross-sectional study of 139 patients（139 eyes） with EDE who were enrolled and classified as obstructive meibomian gland dysfunction（MGD）（n=81） and non-obstructive MGD（n=58） EDE. All patients completed a Standard Patient Evaluation of Eye Dryness（SPEED） questionnaire and were evaluated for average lipid layer thickness（LLT）, tear meniscus height measurements（TMH）, tear break-up time（TBUT）, ocular surface staining score, Schirmer I test（SIT）, lid margin abnormalities, and meibomian gland function and morphology. RESULTS： Age, average LLT, TMH, scores of lid margin abnormalities, meibum quality, meibomian gland loss（MGL）（all P≤0.001）, and TBUT（P=0.03） were all significantly different between obstructive MGD EDE patients and nonobstructive MGD EDE patients. Average LLT in obstructive MGD EDE was correlated with meibomian expressibility（r=-0.541, P≤0.001）, lid margin abnormalities were marginally not significant（r=0.197, P=0.077）, and TMH was correlated with MGL（total MGL： r=0.552, P≤0.001; upper MGL： r=0.438, P≤0.001; lower MGL： r=0.407, P≤0.001）. Average LLT in non-obstructive MGD EDE, was correlated with meibomian expressibility and Oxford staining（r=-0.396, P=0.002; r=-0.461, P≤0.001）. The efficiency of combining average LLT and TMH was optimal, with a sensitivity of 80.2% and a specificity of 74.1%. Obstructive MGD EDE patients had an average LLT≥69 nm and TMH≥0.25 mm, while non-obstructive MGD EDE patients had an average LLT〈69 nm and TMH〈0.25 ***： Obstructive MGD EDE and nonobstructive MGD EDE have significantly different clinical characteristics. Combining average LLT and TMH measurements enhanced their reliability for differentiating these two subtypes and provided guidance for offering more precise treatments for EDE subtypes.

关键词： evaporative dry eye lipid layer thickness tear meniscus height

[Research advances in the transplacental transfer efficiencies of environmental pollutants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 13-21页

作者： Ke-Yu Yuan jun xiong Bi-Feng Yuan School of Public health Wuhan University Wuhan 430071 China.

Industrialization has led to significant increases in the types and quantities of pollutants, with environmental pollutants widely present in various media, including the air, food, and everyday items. These pollutants can enter the human body via multiple pathways, including ingestion through food and absorption through the skin; this intrusion can disrupt the production, release, and circulation of hormones in the body, resulting in a range of illnesses that affect the reproductive, endocrine, and nervous systems. Consequently, these pollutants pose substantial risks to human health. In particular, fetuses are highly sensitive to environmental pollutants during critical stages of development, and exposure during periods of growth and development can result in more-obvious and severe health hazards that can lead to preterm birth, low birth weight, and fetal malformations. The placenta acts as a barrier between the mother and fetus, and selectively filters certain pollutants. While some pollutants remain in the maternal bloodstream, others cross the placental barrier into the fetal umbilical blood through passive diffusion, placental transport proteins, or endocytosis. The transplacental transfer efficiency (TTE) is the ratio of the level of the pollutant in the umbilical blood to that in the maternal blood, and is a valuable metric for evaluating the ability of a pollutant to breach the placental barrier. A higher TTE implies that a larger proportion of pollutants are transferred from the mother to the fetus, thereby amplifying the potential risks to the fetus. Mass spectrometry-based detection methods are extensively used in the chemical and environmental sciences because they are exceptionally sensitive and highly resolving. This analytical technique involves ionizing compounds within a sample and identifying them based on their distinct mass-to-charge ratios; it enables both qualitative and quantitative analyses of various environmental pollutants. Current metho

关键词： chromatography-mass spectrometry environmental pollutants organochlorine pesticides (OCPs) per- and polyfluoroalkyl substances (PFASs) polybrominated diphenyl ethers (PBDEs) polychlorinated biphenyls (PCBs) review transplacental transfer efficiency (TTE)

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan xiong Xin Wang junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

液晶屏线路中导电粒子压合的自动光学检测研究

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液晶与显示 2017年第7期32卷 553-559页

作者：陈玉叶肖可郭振雄何俊杰刘畅陈松岩厦门大学物理科学与技术学院福建厦门361001

在薄膜晶体管液晶显示器线路检测中,常通过对线路中的导电薄膜粒子的计数和定位实现其导电性的自动检测。为了解决窄边框线路中粒子密度增大带来的粒子重叠问题,提出一种采用微分干涉成像和掩模法结合k均值聚类的算法,在分离出粒子的亮... 详细信息

在薄膜晶体管液晶显示器线路检测中,常通过对线路中的导电薄膜粒子的计数和定位实现其导电性的自动检测。为了解决窄边框线路中粒子密度增大带来的粒子重叠问题,提出一种采用微分干涉成像和掩模法结合k均值聚类的算法,在分离出粒子的亮、暗部后,结合图像熵值和粒子的凸性准确分割出粒子。讨论了聚类簇选值的影响,通过不同粒子密度、不同粒子尺寸的样本检验本文算法,并与以往的梯度结合灰度的方法进行对比。结果表明:本文算法在粒子密度较小的区域能达到92.6%的识别率,在粒子密度较大的区域也能达到86%的识别率,分别比梯度加灰度的方法提高了9.9%和42.7%。解决了粒子重叠的问题,并且对光场和成像效果有更好的鲁棒性。

关键词：异向导电胶膜粒子重叠 k均值图像熵凸性

circ_0000376靶向miR-876-3p调控结肠癌细胞进程

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解剖学研究 2023年第2期45卷 114-119,138页

作者：熊隽禾张力林圳滨甘国莲广州中医药大学第二临床医学院广东广州510400 广东省中医院肛肠科广东广州510120

目的探讨circ_0000376对结肠癌细胞SW480迁移、侵袭和凋亡的影响及其分子机制。方法选取30例结肠癌组织及其相应的癌旁组织;体外培养SW480细胞,根据实际转染蛋白情况分别设si-NC组、si-circ_0000376组、miR-NC组、miR-876-3p组、si-ci... 详细信息

目的探讨circ_0000376对结肠癌细胞SW480迁移、侵袭和凋亡的影响及其分子机制。方法选取30例结肠癌组织及其相应的癌旁组织;体外培养SW480细胞,根据实际转染蛋白情况分别设si-NC组、si-circ_0000376组、miR-NC组、miR-876-3p组、si-circ_0000376和anti-miR-876-3p共转染组以及sicirc_0000376和anti-miR-NC共转染组。采取RT-qPCR检测circ_0000376和miR-876-3p的表达水平、Transwell检测细胞迁移和侵袭、流式细胞术检测细胞凋亡、Western blot检测相关蛋白的表达、双荧光素酶报告基因实验检测circ_0000376和miR-876-3p的靶向关系。结果结肠癌组织中circ_0000376较癌旁组织呈高表达(P<0.05),miR-876-3p较癌旁组织呈低表达(P<0.05);沉默circ_0000376或过表达miR-876-3p可有效降低癌细胞恶性行为活性,MMP-2、MMP-9、Bcl-2蛋白也呈更低表达,细胞凋亡活性Bax蛋白呈明显高表达(P<0.05);circ_0000376靶向调控miR-876-3p表达(P<0.05),并发现使miR-876-3p呈现低表达会造成circ_0000376对SW480细胞迁移、侵袭和凋亡形成逆转作用(P<0.05)。结论沉默circ_0000376可通过靶向上调miR-876-3p抑制SW480细胞迁移和侵袭,并促进凋亡。

关键词：结肠癌环状RNA circ_0000376 miR-876-3p SW480细胞株

PVP-Assisted Synthesis of Self-Supported Ni_(2)P@Carbon for High-Performance Supercapacitor

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Research 2019年第1期2019卷 200-209页

作者： Qian he xiong xiong Liu Rui Wu jun Song Chen School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Center for Applied Chemistry University of Electronic Science and Technology of ChinaNo.2006Xiyuan Ave.West Hi-Tech ZoneChengduChina

Highly conductive and stable electrode materials are usually the focus of high-performance *** this work,a unique design of Ni_(2)P@carbon self-supported composite nanowires directly grown on Ni foam was applied for a *** Co3O4 nanowire array was first synthesized on the Ni foam substrate,and the resulting Ni_(2)P@carbon nanocomposite was obtained by hydrothermally coating Co_(3)O_(4) with the Ni-ethylene glycol complex followed by gaseous *** have discovered that the molecular weight of surfactant polyvinylpyrrolidone(PVP)used in the hydrothermal step,as well as the temperature for phosphorization,played very important roles in determining the electrochemical properties of the ***,the sample synthesized using PVP with 10 k molecular weight and phosphorized at 300℃ demonstrated the best supercapacitive performance among the different samples,with the highest capacitance and most stable cyclic *** an asymmetric supercapacitor(ASC)was assembled with this Ni_(2)P@carbon sample as the cathode and activated carbon(AC)as the anode,the ASC device showed excellent capacitances of 3.7 and 1.6 F cm^(-2) at 2 and 50 mA cm^(-2),respectively,and it kept a high capacitance of 1.2 F cm^(-2) after 5000 cycles at a current rate of 25 mA cm^(-2).In addition,the ASC could reach a high energy density of about 122.8 Wh kg^(-1) at a power density of 0.15 kW kg^(-1) and 53.3 Wh kg^(-1) at the highest power density of 3.78 kW kg^(-1).Additionally,this device also had the ability to power up 16 red LEDs effortlessly,making it a strong candidate in electrochemical energy storage for practical usage.

关键词： composite nanowires capacitance

Shock Tube Measurement of Ethylene Ignition Delay Time and Molecular Collision Theory Analysis

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Chinese Journal of Chemical Physics 2016年第6期29卷 761-766,I0002页

作者： Xiao-he xiong Yan-jun Ding Shuo Shi Zhi-min Peng StateKeyLabofPowerSystems DepartmentofThermalEngineeringTsinghuaUniversityBeij'inE100084China

In this study, 75% and 96% argon diluent conditions were selected to determine the ig- nition delay time of stoichiometric mixture of C2Ha/O2/Ar within a range of pressures （1.3-：3.0 arm） and temperatures （1092-1743 K）. Results showed a logarithmic linear rela- tionship of the ignition delay time with the reciprocal of temperatures. Under both two diluent conditions, ignition delay time decreased with increased temperature. By multiple linear regression analysis, the ignition delay correlation was deduced. According to this correlation, the calculated ignition delay time in 96% diluent was found to be nearly five times that in 75% diluent. To explain this discrepancy, the hard-sphere collision theory was adopted, and the collision numbers of ethylene to oxygen were calculated. The total collision numbers of ethylene to oxygen were 5.99×10^30 s^-1cm^-3 in 75% diluent and 1.53×10^29 s^-1cm^-3 in 96% diluent （about 40 times that in 75% diluent）. According to the discrepancy between ignition delay time and collision numbers, viz. 5 times corresponds to 40 times, the steric factor can

关键词： Shock tube Ethylene Ignition delay Molecule collision