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Nano Research 2024年第9期17卷 8036-8044页

作者： Song Kou Shu lian Xiaodong Xie Wei Ren Yu jin jiahui Bao Honghui Ou Guidong Yang XjTU-Oxford International joint Laboratory for Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China Fujian-Taiwan-Hongkong-Macao Science and Technology Cooperation Base of Intelligent Pharmaceutics Institute of OceanographyCollege of Materials and Chemical EngineeringMinjiang UniversityFuzhou 350108China School of Food and Bioengineering Fujian Polytechnic Normal UniversityFuqing 350300China

Organic conjugated polymers have received extensive attention due to their unique electronic ***,there have been relatively few reports on the dark photocatalytic reactions utilizing organic conjugated ***,we report the successful synthesis of an organic conjugated polymer based on poly(heptazine imide)nanocrystals(CnnCs)for H_(2)O_(2)evolution and biomedical applications using a simple salt molten method and sonication-centrifugation *** results show that these colloid CnnCs have the characteristics of photogenerated electrons accumulation and realize dark photocatalysis with high reducibility under visible light ***,these accumulating photogenerated electrons can reduce O_(2)in darkness to produce H_(2)O_(2).In addition,cytotoxicity tests were conducted and it was found that H_(2)O_(2)produced under dark conditions could oxidize L-arginine(L-Arg)to NO,which effectively killed tumors in the *** work provides an important strategy to construct organic conjugated semiconductor nanocrystals and applying them to future energy and biomedical fields.

关键词： poly(heptazine imide) photocatalysis photogenerated electrons hydrogen peroxide evolution cancer treatment

Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

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National Science Review 2024年第4期11卷 123-129页

作者： Gan Xu Yun-Shu Cui Xue-lian jiang Cong-Qiao Xu jun Li Xu-Dong Chen jiangsu Collaborative Innovation Center of Biomedical Functional Materials and jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage ***,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron *** this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic *** chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ *** ground-state electron spin is theoretically predicted to be S=32/2 for the *** existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex

Microgels for Cell Delivery in Tissue Engineering and Regenerative Medicine

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Nano-Micro Letters 2024年第10期16卷 576-617页

作者： Leyan Xuan Yingying Hou Lu liang jialin Wu Kai Fan Liming lian jianhua Qiu Yingling Miao Hossein Ravanbakhsh Mingen Xu Guosheng Tang Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target and Clinical Pharmacology the NMPA and State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences and the Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhou 511436People's Republic of China School of Automation Hangzhou Dianzi UniversityHangzhou 310018People's Republic of China Department of Biomedical Engineering The University of AkronAkronOH 44325USA Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Microgels prepared from natural or synthetic hydrogel materials have aroused extensive attention as multifunctional cells or drug carriers,that are promising for tissue engineering and regenerative *** can also be aggregated into microporous scaffolds,promoting cell infiltration and proliferation for tissue *** review gives an overview of recent developments in the fabrication techniques and applications of microgels.A series of conventional and novel strategies including emulsification,microfluidic,lithography,electrospray,centrifugation,gas-shearing,three-dimensional bioprinting,*** discussed in *** characteristics and applications of microgels and microgel-based scaffolds for cell culture and delivery are elaborated with an emphasis on the advantages of these carriers in cell ***,we expound on the ongoing and foreseeable applications and current limitations of microgels and their aggregate in the field of biomedical *** stimulating innovative ideas,the present review paves new avenues for expanding the application of microgels in cell delivery techniques.

关键词： Microgels Cell delivery Scaffolds 3D bioprinting Single-cell microgels

Lipid nanoparticles deliver mRNA to the blood-brain barrier

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Nano Research 2024年第10期17卷 9126-9134页

作者： Yanina Kuzminich Avraham Shakked Randi Calkins Sebastian Rudden Camille jones jessie Doan Bora jang Elisa Schrader Echeverri Ryan Zenhausern Liming lian David Loughrey Hannah E.Peck Rachelle Wiese Dorothy Koveal Philip j.Santangelo james E.Dahlman George C.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Parker H.Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA Wallace H.Coulter Department of Biomedical Engineering Emory University School of Medicine and Georgia Institute of TechnologyAtlantaGA 30332USA

Lipid nanoparticles(LNPs)have delivered RNA to hepatocytes in patients after intravenous *** clinical data support efforts to design LNPs that transfect cells in the central nervous system(CNS).However,delivery to the CNS has been difficult,in large part because quantifying on-target delivery alongside common off-target cell types in adult mice remains *** we report methods to isolate different cell types from the CNS,and subsequently present mRNA delivery readouts using a liver-detargeted *** data suggest that LNPs without targeting ligands can transfect cerebral endothelial cells in mice after intravenous *** the difficulty of crossing the blood-brain barrier,they also underscore the value of quantifying delivery in the CNS with cell-type resolution instead of whole-tissue resolution.

关键词： lipid nanoparticle mRNA nanomedicine central nervous system blood-brain barrier

Robust In-Zr Metal-Organic Framework Nanosheets as Ultrathin Interlayer Toward High-Rate and Long-Cycle Lithium-Sulfur Batteries

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CCS Chemistry 2024年第4期6卷 988-998页

作者： Zhibin Cheng jie lian Yiyang Chen Yiyang Tang Yulian Huang jindan Zhang Shengchang Xiang Zhangjing Zhang Fujian Key Laboratory of Polymer Materials College of Materials Science and EngineeringFujian Normal UniversityFuzhou 350007 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002

Lithium-sulfur(Li-S)batteries have great potential as the next generation of high-energy-density storage ***,the practical viability of Li-S batteries is largely hampered by undesirable shuttling behavior and sluggish conversion kinetics of ***,a multifunctional separatormodified layer(In/Zr-BTB nanosheets)with the merits of robust structures and efficient catalytic metal sites has been ***/Zr-BTB nanosheets inherit the stable structure from Zr-BTB and strengthen the catalytic performance due to the introduction of highly catalytic species indium via metal-ion *** thickness and areal mass loading of the modified layer are only 260 nm and 0.011 mg/cm2,***,the ultrathin modification layers with efficient catalytic species,compact structures,and uniform pore channels can realize fast Li+transport,effective polysulfide interception,and rapid catalytic ***,the In/Zr-BTB@PP cell with a high sulfur content of 80 wt%could maintain high capacity retention of 85.6%with a low capacity fading rate of 0.048%per cycle after 300 cycles even at a high current rate of 2 *** work opens a new door toward the design of versatile metal-organic framework(MOF)nanosheets and multifunctional separators for high-energy-density Li-S batteries.

关键词： lithium-sulfur batteries metal-organic framework shuttle effect energy storage separator modification

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“非洲独龙玉”的矿物成分及谱学特征

光谱学与光谱分析 2024年第6期44卷 1676-1683页

作者：余炼钢郑金宇德宏师范高等专科学校艺术学院云南德宏678400 中国地质大学(武汉)珠宝学院湖北武汉430074

“非洲独龙玉”是近年来滇西珠宝市场上涌现的新兴玉石品种。其鲜艳绿色呈脉状和团絮状分布于无色至灰白色基体上,局部存在红褐色。品质优于云南怒江州“独龙玉”,市场前景引起业界广泛关注,但其宝石学特征及矿物种属尚不清楚。运用红... 详细信息

“非洲独龙玉”是近年来滇西珠宝市场上涌现的新兴玉石品种。其鲜艳绿色呈脉状和团絮状分布于无色至灰白色基体上,局部存在红褐色。品质优于云南怒江州“独龙玉”,市场前景引起业界广泛关注,但其宝石学特征及矿物种属尚不清楚。运用红外光谱仪、拉曼光谱仪、X射线粉晶衍射仪、扫描电子显微镜及能谱、X射线荧光光谱仪、紫外-可见光谱仪等测试方法对其矿物组成及结构特征、化学成分、谱学特征及颜色成因等进行了研究。红外光谱测试表明该玉石的绿色部分显示白云母与石英的红外特征混合谱,其中3623、694、1080和1619 cm^(-1)处特征吸收峰指示白云母。拉曼光谱测试显示玉石基体部分在204、262、355、395和463 cm^(-1)处具α-石英特征峰,绿色部分在261、395、694、3623 cm^(-1)处具白云母特征峰,表面金属光泽矿物在343、379和437 cm^(-1)处具黄铁矿特征峰,局部浸染状橙黄-红褐色矿物在224、295、409、493和610 cm^(-1)处具赤铁矿特征峰。X射线粉晶衍射测试在3.48、2.98、2.56处特征衍射峰指示为2M 1型白云母。扫描电子显微镜及能谱面扫描显示白云母呈纤柱状、鳞片状集合体,单颗粒长约25~40μm,宽约2~4μm;少量杂质矿物辉砷镍矿呈近似立方体晶形,粒径约为10~15μm,由黄铁矿蚀变作用形成,其中Fe、Co部分类质同像替代Ni,As含量高于S,指示为高温热液矿床成因。综合化学成分及紫外-可见光谱特征表明,致色矿物白云母含Ba、Cr,不含Fe,其中Cr为致色元素。除颜色特征外,利用多种谱学的方法揭示了“非洲独龙玉”与云南怒江“独龙玉”在杂质矿物、化学成分及致色元素方面的差异,可作为区分二者的有效证据,同时丰富了天然绿色石英质玉的成分信息和谱学特征数据,亦为进一步做“非洲独龙玉”的产地溯源及成矿地质条件背景研究奠定了理论基础。

关键词： “非洲独龙玉” 矿物组成辉砷镍矿颜色成因谱学特征

Co-assembly of chiral copper(I) complexes and achiral polymer for enhanced circularly polarized luminescence

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Science China Chemistry 2024年

作者： Ting Liu Muxin Yu Yangxingyu Ye Yunfang Zhao Zhijia Li Zhiyuan Wu Feilong jiang lian Chen Maochun Hong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences (CAS) University of Chinese Academy of Sciences Organic Optoelectronics Engineering Research Center of Fujian's Universities College of Electronics and Information ScienceFujian Jiangxia University

Circularly polarized luminescence（CPL） has attracted growing attention for their promising applications in chiral functional devices. Achieving CPL materials with both high luminescence dissymmetry factors(glum) and emission efficiency is attractive but remains great challenges. In this study, a pair of chiral Cu（I） complexes named R/S-CuI with C2symmetry were synthesized,exhibiting no emission in solution and weak CPL with glum= ± 3.3×10-3in crystalline state. Transparent chiral films（R/S-CuIfilm） were developed through the co-assembly of R/S-CuI and achiral polymer PMMA. The films show bright green luminescence with the quantum yields about 200 times higher than those in crystalline state. Meanwhile, the maximum |glum| value is also amplified by approximately 2.5 times, reaching to 8.7×10-3. Mechanism investigation suggests that the notable enhancement of luminescence efficiency can be ascribed to the restriction of the intramolecular motions and the elimination of the oxygen quenching effect, while the improvement in glumvalues may be explained by the chirality transfer from the axially chiral molecule R/S-CuI to the achiral polymer PMMA. Furthermore, R/S-CuI-film were used for advanced information encryption applications based on its CPL characteristics. This work may provide new inspirations for the construction of CPL-active films with high performance, thereby expediting their further development.

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Spatio-Temporal Trend and Geographic Disparity of Infertility Prevalence in Burkina Faso, 2011 to 2020

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Open journal of Obstetrics and Gynecology 2024年第8期14卷 1288-1302页

作者： Oumarou Nabi René Tokira Poubouré Yabré Pratibha Shrestha Aoua Sangaré jérémie Sawadogo Miézan Brigitte Aka Smaila Ouédraogo Min lian Division of General Medical Sciences Department of Medicine Washington University School of Medicine St. Louis Missouri United States of America Division of Public Health Department of Public Health CHU Yalagado Ouedraogo Joseph Ki-Zerbo University Ouagadougou Burkina Faso Division of Public Health Sciences Department of Surgery Washington University School of Medicine St. Louis Missouri United States of America Research Group on Communication Issues Grenoble Alpes University Grenoble France Alvin j. Siteman Cancer Center Washington University School of Medicine St. Louis Missouri United States of America

Background: Infertility affected 10% to 25% of couples globally, and about half of the infertility cases were reported in sub-Saharan Africa. Infertility poses significant social, cultural, and health challenges, particularly for women who often face stigmatization. However, comprehensive and nationally representative data, including prevalence, temporal trends, and risk factors, are lacking, prompting a study in Burkina Faso to address the need for informed policies and programs in infertility care and management. Objectives: This study aims to better understand the spatiotemporal trend of infertility prevalence in Burkina Faso. Methodology: This is a retrospective population-based study of women infertility from healthcare facilities in Burkina Faso, during january 2011 to December 2020. We calculated the prevalence rates of infertility and two disparity measures, and examined the spatiotemporal trend of infertility. Results: Over the 10-year period (2011 to 2020), 143,421 infertility cases were recorded in Burkina Faso healthcare facilities, resulting of a mean prevalence rate of 3.61‰ among childbearing age women and 17.87‰ among women who consulted healthcare facilities for reproductive issues (except contraception). The findings revealed a significant increase of infertility, with the prevalence rate varied from 2.75‰ in 2011 to 4.62‰ in 2020 among childbearing age women and from 13.38‰ in 2011 to 26.28‰ in 2020 among women who consulted healthcare facilities for reproductive issues, corresponding to an estimate annual percentage change of 8.31% and 9.80% respectively. There were significant temporal and geographic variations in the prevalence of infertility. While relative geographic disparity decreased, absolute geographic disparity showed an increasing trend over time. Conclusion: The study highlights an increasing trend of infertility prevalence and significant geographic variation in Burkina Faso, underscoring the urgent necessity for etiologic research o

关键词： Infertility Prevalence Temporal Trend Geography Disparity

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基于U-Net变体的医学图像分割算法综述

计算机工程与应用 2024年第11期60卷 32-49页

作者：崔珂田启川廉露北京建筑大学电气与信息工程学院北京100044

U-Net简单高效的网络结构,被广泛应用于医学图像分割任务中,学者们针对U-Net结构进行了很多的研究和改进。基于U-Net网络结构的改进方法从以下方面进行归纳总结:总结了U-Net网络在医学图像分割领域的关键挑战;归纳了常用于U-Net网络的... 详细信息

U-Net简单高效的网络结构,被广泛应用于医学图像分割任务中,学者们针对U-Net结构进行了很多的研究和改进。基于U-Net网络结构的改进方法从以下方面进行归纳总结:总结了U-Net网络在医学图像分割领域的关键挑战;归纳了常用于U-Net网络的医学图像数据集格式及特点;重点总结U-Net和U-Net变体算法六大改进机制:跳跃连接机制、生成对抗网络、残差连接机制、3D-UNet、Transformer机制、密集连接机制。最后,探讨六大改进机制与常用医学数据之间的关系,并指出未来改进思路和方向,激发U-Net在医学图像分割的无限潜力。

关键词： U-Net变体医学图像分割语义分割深度学习改进机制

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注意力机制下的多层次特征融合图像去雾算法

福州大学学报（自然科学版） 2024年第1期52卷 7-13页

作者：连文杰叶少珍福州大学计算机与大数据学院福建福州350108 福州大学智能制造仿真研究院福建福州350108

提出一种基于注意力机制的多层次特征融合的图像去雾算法.该算法通过残差密集网络和自校准卷积网络来提取不同尺度的特征,再利用双重注意单元和像素注意力将特征融合重建.同时采用一种由均方误差损失、边缘损失和鲁棒性损失函数相结合... 详细信息

提出一种基于注意力机制的多层次特征融合的图像去雾算法.该算法通过残差密集网络和自校准卷积网络来提取不同尺度的特征,再利用双重注意单元和像素注意力将特征融合重建.同时采用一种由均方误差损失、边缘损失和鲁棒性损失函数相结合的损失函数,可以更好地保留细节特征.实验表明,该算法与其他去雾算法相比在峰值信噪比和结构相似度指标上得到一定的提高,去雾图像在主观视觉上取得了较好表现.

关键词：图像去雾注意力机制多层次特征融合