检索结果-南通市图书馆

Resolution and contrast enhancement of laser-scanning multiphoton microscopy using thulium-doped upconversion nanoparticles

引用

Nano Research 2019年第12期12卷 2933-2940页

作者： Alexey B.Kostyuk Artem D.Vorotnov Andrey V.Ivanov Arthur B.Volovetskiy Aleksandr V.Kruglov lyudmila m.sencha Liuen Liang Evgenii L.Guryev Vladimir A.Vodeneev Sergey m.Deyev Yiqing Lu Andrei V.Zvyagin Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603950Russia Center of Biomedical Engineering Institute of Molecular MedicineSechenov UniversityMoscow 119991Russia ARC Centre of Excellence"Nanoscale BioPhotonics" Department of Physics and AstronomyMacquarie UniversitySydney 2109Australia Institute ofBioorganic Chemistry Russian Academy of SciencesMoscow 117997Russia

High-contrast optical imagi ng is achievable using phosphoresce nt labels to suppress the short-lived background due to the optical backscatterand autofluoresce ***,the long-lived phosphorescence is generally incompatible with high-speed laser-scan ning imaging ***,we show that upc on versi on nan oparticles of structure NaYF4:Yb co-doped with 8%Tm(8T-UCNP)in combi nation with a commerciallaser-scanning multiphoton microscopy are uniquely suited for labeling biological systems to acquire high-resolution images with the enhancedcon *** comparison with many phosphoresce nt labels,the 8T-UCNP emission lifetime of-15μs affords rapid image ***-order optical nonlinearity of the 8T-UCNP(n=4,as confirmed experimentally and theoretically)afforded pushing the resolution limitattain able with UCNPs to the *** contrast enha nceme nt was achieved by suppressing the backgro und using(i)ban dpassspectral filtering of the narrow emission peak of 8T-UCNP at 455-nm,and(ii)time-gating implemented with a time-correlated single-photon counting system that demonstrated the contrast enhancement of>2.5-fold of polyethyle neimine-coated 8T-UCNPs take n up by huma nbreast adeno carcinoma cells *** a result,discrete 8T-UCNP nan oparticles became clearly observable in the freshly excised splee ntissue of laboratory mice 15-min post in trave nous injectio n of an 8T-UCNP *** dem on strated approach paves the way forhigh-contrast,high-resoluti on,and high-speed multiphot on microscopy in challe nging envir onments of i ntense autofluorescence,exogenous staining,and turbidity,as typically occur in intravital imaging.

关键词： upconversion nanoparticles autofluorescence time-gated imaging scanning microscopy time-correlated single photon counting

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–SiO_(2)glass fibers

引用

Photonics Research 2024年第2期12卷 260-270页

作者： SERGEY ALYSHEV ALEXANDER VAKHRUSHEV ALEKSANDR KHEGAI ELENA FIRSTOVA KONSTANTIN RIUmKIN mIKHAIL mELKUmOV lyudmila ISKHAKOVA ANDREY UmNIKOV SERGEI FIRSTOV Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication *** development of optical amplifiers operating in the O-,E-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass *** this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(mCVD)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is ***,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A rare case of cardiac and ophthalmic manifestations of meningococcal septicemia

引用

World Journal of Emergency medicine 2024年第4期15卷 328-330页

作者： Svetlana Rachina Anastasia Shchendrygina Heshan Radeesha de Silva Svetlana Tarasenko Nadezhda mukhina Irina Komarova Ludmila Fedina Elena Burmistrova Elvira martens Sergey Sidorenko Vladimir Gostev Dmitry Polev Alina Saitova lyudmila Kraeva Nikita Goncharov Irina Zvetkova Department of Hospital Therapy I M Sechenov First Moscow State Medical UniversityMoscow 119048Russia Outpatient Clinic#64 Moscow 119048Russia Department of Cardiology City Clinical Hospital n.a.S.S.YudinMoscow 119048Russia Department of medical microbiology and molecular Epidemiology Pediatric Research and Clinical Center for InfectiousDiseasesSaint Petersburg 197022Russia Department of medical microbiology North-Western State Medical University Named After I.I.MechnikovSaintPetersburg 191015Russia Department of Epidemiology Saint-Petersburg Pasteur InstituteSaint Petersburg 197101Russia

Acute pericarditis is usually a self-limiting disorder that commonly occurs due to viral etiology or unexplained *** pericarditis(mP)is a remarkably uncommon clinical entity that manifests as a complication during the acute or convalescent phase of meningococcal ***,its occurrence within the context of meningococcal septicemia has also been *** report a rare case of a previously healthy male patient who developed both acute pericarditis and uveitis as a presentation of meningococcal septicemia,with no characteristic skin rashes or meningeal signs.

关键词： acute Acute rare

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficient algorithm for big data clustering on single machine

引用

CAAI Transactions on Intelligence Technology 2020年第1期5卷 9-14页

作者： Rasim m.Alguliyev Ramiz m.Aliguliyev lyudmila V.Sukhostat Institute of Information Technology Azerbaijan National Academy of Sciences9AB.Vahabzade StreetAZ1141 BakuAzerbaijan

Big data analysis requires the presence of large computing powers, which is not always feasible. And so, itbecame necessary to develop new clustering algorithms capable of such data processing. This study proposes a newparallel clustering algorithm based on the k-means algorithm. It significantly reduces the exponential growth ofcomputations. The proposed algorithm splits a dataset into batches while preserving the characteristics of the initialdataset and increasing the clustering speed. The idea is to define cluster centroids, which are also clustered, for eachbatch. According to the obtained centroids, the data points belong to the cluster with the nearest centroid. Real largedatasets are used to conduct the experiments to evaluate the effectiveness of the proposed approach. The proposedapproach is compared with k-means and its modification. The experiments show that the proposed algorithm is apromising tool for clustering large datasets in comparison with the k-means algorithm.

关键词： algorithm. algorithm batch

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

阿尔泰-萨彦山的新构造运动和区域控震断裂的再活化

引用

地学前缘 2021年第5期28卷 301-319页

作者： mikhail m.BUSLOV lyudmila P.ImAEVA Sobolev V.S.Institute of Geology and mineralogy Siberian Branch of the RAS630090 NovosibirskRussia Kazan Federal University 420008KazanRussia Institute of the Earth's Crust Siberian Branch of RAS664033 IrkutskRussia Academy of Sciences of the Republic of Sakha(Yakutia) 677007 YakutskRussia

阿尔泰-萨彦山系和新构造结构的形成被认为是印度欧亚板块碰撞带来的远程陆内变形的结果。在本次构造模型中,我们对地质、地震活动数据和地形资料进行了联合分析,认为中亚山带北部地形和地震活动的最大变化仅限于晚古生代区域断层的交... 详细信息

阿尔泰-萨彦山系和新构造结构的形成被认为是印度欧亚板块碰撞带来的远程陆内变形的结果。在本次构造模型中,我们对地质、地震活动数据和地形资料进行了联合分析,认为中亚山带北部地形和地震活动的最大变化仅限于晚古生代区域断层的交叉地带。断层的交叉和接合处应被视为增加基底破碎程度、影响局部应力场变化和预先定位m≥5级的地震震源的最重要的构造因素之一。由此,结合Charysh Terekta和Kurai区域断层交叉带出现的氦和钙华,本次研究获得了发震前兆的一些判断规律。

关键词：阿尔泰-萨彦山 Kurai-Chuya盆地活动构造 2003年9月27日的阿尔泰地震断层活化控震断层

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Construction of RNA nanotubes

引用

Nano Research 2019年第8期12卷 1952-1958页

作者： Hui Li Shaoying Wang Zhouxiang Ji Congcong Xu lyudmila S. Shlyakhtenko Peixuan Guo Center for RNA Nanobiotechnology and Nanomedicine Division of Pharmaceutics and Pharmaceutical ChemistryCollege of Pharmacy/Department of Physiology & Cell BiologyCollege of Medicine/Dorothy M. Davis Heart and Lung Research Institute and James Comprehensive Cancer CenterThe Ohio State UniversityColumbusOH43210USA UNmC Nanoimaging Core Facility Department of Pharmaceutical SciencesCollege of Pharmacy University of Nebraska Medical CenterOmahaNE68182USA Present address: University of California San FranciscoCA94158USA Present address: P&Z Biological Technology NewarkNJ07103USA

Nanotubes are miniature materials with significant potential applications in nanotechnological, medical, biological and material sciences. The quest for manufacturing methods of nano-mechanical modules is in progress. For example, the application of carbon nanotubes has been extensively investigated due to the precise width control, but the precise length control remains challenging. Here we report two approaches for the one-pot self-assembly of RNA nanotubes. For the first approach, six RNA strands were used to assemble the nanotube by forming a 11 nm long hollow channel with the inner diameter of 1.7 nm and the outside diameter of 6.3 nm. For the second approach, six RNA strands were designed to hybridize with their neighboring strands by complementary base pairing and formed a nanotube with a six-helix hollow channel similar to the nanotube assembled by the first approach. The fabricated RNA nanotubes were characterized by gel electrophoresis and atomic force microscopy (AFm), confirming the formation of nanotube-shaped RNA nanostructures. Cholesterol molecules were introduced into RNA nanotubes to facilitate their incorporation into lipid bilayer. Incubation of RNA nanotube complex with the free-standing lipid bilayer membrane under applied voltage led to discrete current signatures. Addition of peptides into the sensing chamber revealed discrete steps of current blockage. Polyarginine peptides with different lengths can be detected by current signatures, suggesting that the RNA-cholesterol complex holds the promise of achieving single molecule sensing of peptides.

关键词： RNA nanotechnology peptide sensing RNA nanotube nanobiotechnology

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Periodical zonal character of damage near the openings inhighly-stressed rock mass conditions

引用

Journal of Rock mechanics and Geotechnical Engineering 2016年第2期8卷 164-169页

作者： Vladimir Vmakarov mikhail AGuzev Vladimir NOdintsev lyudmila SKsendzenko Far-Eastern Federal University VladivostokRussia Russian Academy of Sciences MoscowRussia

Rock mass damage at great depths near underground openings is often of a zonal ***,the classical elastoplastic theory fails to explain sufficiently all properties of zonal failure structures.A new non-Euclidean mathematical model for highly-stressed rock mass was developed based on the principles of mechanics of defected material and non-equilibrium *** were developed to determine model parameters that provide satisfactory correspondence between the experimental findings concerning faulted zonal structures near openings at great depths and mathematical *** mechanism of this phenomenon was discovered which consisted in a periodical character of stresses in the surrounding rock mass and development of tensile macrocracks at zones of maximal tangential *** relationships between the cracking zone width and rock mass strength were established.

关键词： Rock failure Openings Zones modeling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Kinetics and mechanism of natural wolframite interactions with sodium carbonate

引用

International Journal of minerals,metallurgy and materials 2019年第11期26卷 1364-1371页

作者： Evgeniy Nikolaevich Selivanov Kirill Vladimirovich Pikulin lyudmila Ivanovna Galkova Roza Iosifovna Gulyaeva Sofia Aleksandrovna Petrova Institute of metallurgy of the Ural Branch of the Russian Academy of Sciences

The kinetics and mechanism of natural wolframite interactions with sodium carbonate during air heating were studied.X-ray phase and X-ray microanalysis were used to establish that the initial monocrystalline wolframite consists of Fe0.5 mn0.5 WO4 and Fe0.3 mn0.7 *** thermal analysis showed that the interaction of wolframite with sodium carbonate begins above 450°C with the formation of tungstate,sodium ferrite,iron oxides,and *** experiments on sintering with the subsequent removal of water-soluble compounds(leaching)tracked the change in the structure of *** atomic ratio of Fe/mn in wolframite does not change up to 600°C,and subsequently decreases to 0.2 during heating,which allows the mechanism of the process to be identified and indicates the greater reactivity of wolframites with an increased proportion of *** analysis with data processing using non-isothermal kinetics established that the interaction of wolframite with sodium carbonate in an air stream proceeds via a two-stage mechanism,wherein the first stage is limited by diffusion(activation energy,E=243 kJ/mol)and the second stage is limited by autocatalysis(activation energy,E=212 k J/mol)due to the formation of a Na2 WO4–Na2 CO3 eutectic.

关键词： wolframite structure sodium carbonate sintering thermal analysis kinetics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chondroitin sulfate and glucosamine combination in patients with knee and hip osteoarthritis:A long-term observational study in Russia

引用

World Journal of Orthopedics 2023年第6期14卷 443-457页

作者： Alexander m Lila lyudmila I Alekseeva Andrey A Baranov Elena A Taskina Natalya G Kashevarova Natalia A Lapkina Evgeny A Trofimov Director Research Institute of Rheumatology Named after VA NasonovaMoscow 115522MoscowRussia Bone and Joints metabolic Diseases Laboratory Research Institute of Rheumatology Named after VA NasonovaMoscow 115522MoscowRussia Department of Therapy Clinical Laboratory Diagnostics and Medical BiochemistryYaroslavl State Medical UniversityYaroslavl 150000YaroslavlRussia Department of Therapy and Rheumatology North-Western State Medical University named after I.I.MechnikovSt.Petersburg 191015St.PetersburgRussia

BACKGROUND Oral treatment of glucosamine(GA) combined with chondroitin sulfate(CS) was reportedly effective for pain relief and function improvement in osteoarthritis patients with moderate to severe knee pain in clinical trials. While the effectiveness of GA and CS on both clinical and radiological findings has been demonstrated, only a few high-quality trials exist. Therefore, controversy regarding their effectiveness in real-world clinical practice *** To investigate the impact of GA + CS on clinical outcomes of patients with knee and hip osteoarthritis in routine clinical *** A multicenter prospective observational cohort study included 1102 patients of both genders with knee or hip osteoarthritis(Kellgren & Lawrence grades Ⅰ-Ⅲ) in 51 clinical centers in the Russian Federation from November 20, 2017, to march 20,2020, who had started to receive oral capsules of glucosamine hydrochloride 500 mg and CS 400mg according to the approved patient information leaflet starting from 3 capsules daily for 3 wk,followed by a reduced dosage of 2 capsules daily before study inclusion(minimal recommended treatment duration is 3-6 mo). Changes in subscale scores [Pain, Symptoms, Function, and Quality of Life(QOL)] of the Knee Injury and Osteoarthritis Outcome Score(KOOS)/Hip Disability and Osteoarthritis Outcome Score(HOOS) questionnaires during the observational period(up to 54-64wk with a total of 4 visits). Patients’ treatment satisfaction, data on the combined oral use of glucosamine hydrochloride and CS, concomitant use of non-steroidal anti-inflammatory drugs(NSAIDs), and adverse events(AEs) were also *** A total of 1102 patients with knee and hip osteoarthritis were included in the study. The mean patient age was 60.4 years, most patients were women(87.8%), and their average body mass index was 29.49 kg/m2. All subscale scores(Pain, Symptoms, Function, and QOL) of the KOOS and HOOS demonstrated clinically and statistically significant im

关键词： Glucosamine Chondroitin sulfate Knee osteoarthritis Hip osteoarthritis Knee injury and osteoarthritis outcome score Hip disability and osteoarthritis outcome score

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ultrathin metal Silicate Hydroxide Nanosheets with moderate metal-Oxygen Covalency Enables Efficient Oxygen Evolution

引用

Energy & Environmental materials 2022年第1期5卷 231-237页

作者： Jiexin Zhu Shikun Li Zechao Zhuang Shan Gao Xufeng Hong Xuelei Pan Ruohan Yu Liang Zhou lyudmila V.moskaleva Liqiang mai State Key Laboratory of Advanced Technology for materials Synthesis and Processing Wuhan University of Technology Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology University of Bremen Department of Chemistry University of the Free State Collage of Chemistry & Chemical Engineering Anhui University Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen Valleyfoshan guangdong 528200china

Exploring efficient,cost-effective,and durable electrocatalysts for electrochemical oxygen evolution reaction(OER)is pivotal for the large-scale application of water *** advance has demonstrated that the activity of electrocatalysts exhibits a strong dependence on the surface electronic ***,a series of ultrathin metal silicate hydroxide nanosheets(UmSHNs)m_(3)Si_(2)O_(5)(OH)_(4)(m=Fe,Co,and Ni)synthesized without surfactant are introduced as highly active OER *** silicate hydroxide nanosheets show an optimal OER activity with overpotentials of 287 and 358 m V at 1 and 10 m A cm^(-2),*** experimental and theoretical studies,it is found that the OER activity of UmSHNs is dominated by the metal-oxygen covalency(mOC).High OER activity can be achieved by having a moderate mOC as reflected by aσ^(*)-orbital(e_(g))filling near unity and moderate[3d]/[2p]***,the UmSHNs exhibit favorable chemical stability under oxidation *** contribution provides a scientific guidance for further development of active metal silicate hydroxide catalysts.

关键词： electrocatalysis metal silicate hydroxide metal-oxygen covalency oxygen evolution reaction ultrathin nanosheet

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：