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Cytotoxicity and non-specific cellular uptake of bare and surface-modified upconversion nanoparticles in human skin cells

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nano Research 2015年第5期8卷 1546-1562页

作者： Anna E. Guller Alia n. Generalova Elena V. Petersen Andrey V. nechaev Inna A. Trusova nikolay n. Landyshev Annemarie nadort Ekaterina A. Grebenik Sergey M. Deyev Anatoly B. Shekhter Andrei V. Zvyagin Macquarie University Australia I.M. Sechenov First Moscow State Medical University Russia Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Russia nizhny novgorod State University Russia Moscow Institute of Physics and Technology Russia Moscow State University of Fine Chemical Technologies Russia University of Amsterdam the Netherlands

The cytotoxicity and non-specific cellular uptake of the most popular composition of upconversion nanoparticle （UCnP）, naYF4：Yb^3＋：Er^3＋, is reported using normal human skin cells, including dermal fibroblasts and immortalized human epidermal linear keratinocytes （HaCaT）. A new hydrophilization reaction of as-synthesized UCnPs based on tetramethylammonium hydroxide （TMAH） enabled evaluation of the intrinsic cytotoxicity of bare UCnPs. The cytotoxicity effects of the UCnP surface-coating and polystyrene host were investigated over the concentration range 62.5-125 μg/mL with 24-h incubation, using a MTT test and optical microscopy. The fibroblast viability was not compromised by UCnPs, whereas the viability of keratinocytes varied from 52% ± 4% to 100% ± 10% than the control group, depending on the surface modification. Bare UCnPs reduced the keratinocyte viability to 76% ± 3%, while exhibiting profound non-specific cellular uptake. Hydrophilic poly（D,L-lactide）- and poly（maleic anhydride-alt-l-octadecene）-coated UCnPs were found to be least cytotoxic among the polymer-coated UCnPs, and were readily internalized by human skin cells. Polystyrene microbeads impregnated with UCnPs remained nontoxic. Surprisingly, no correlation was found between UCnP cytotoxicity and the internalization level in cells, although the latter ranged broadly from 0.03% to 59%, benchmarked against 100% uptake level of TMAH-UCnPs.

关键词： nanoparticle upconversion surface modification biocompatibility cytotoxicity human skin

Counting stripes:revision of the Lipinia vittigera complex(Reptilia, Squamata, Scincidae) with description of two new species from Indochina

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Zoological Research 2019年第5期40卷 358-393页

作者： nikolay A. Poyarkov Jr. Peter Geissler Vladislav A. Gorin Evgeniy A. Dunayev Timo Hartmann Chatmongkon Suwannapoom Department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University Moscow 119991 Russia Joint Russian-Vietnamese Tropical Research and Technological Center Nghia Do Cau Giay Hanoi Vietnam Museum natur und Mensch Freiburg 79098 Germany Zoological Museum Moscow State University Moscow 125009 Russia Zoological Research Museum Alexander Koenig Bonn 53113 Germany School of Agriculture and natural Resources University of Phayao Phayao 56000 Thailand

We provide an integrative taxonomic analysis of the Lipinia vittigera species complex from mainland Southeast Asia. Based on examination of external morphology, color pattern, and 681 base pairs of the cytochrome oxidase subunit I (COI) mitochondrial gene, we demonstrate the presence of four morphologically distinct lineages of Lipinia in Vietnam, Cambodia, Thailand, and Malaysia, showing a sequence divergence ranging 15.5%–20.4%. All discovered lineages are discretely diagnosable from one another by a combination of scalation traits and color patterns. A review of the published distribution data and a re-examination of available type material revealed the following results:(1) distribution of L. vittigera (Boulenger, 1894) sensu stricto is restricted to Sundaland and the Thai-Malay Peninsula south of the Isthmus of Kra;(2) L. microcercus (Boettger, 1901) stat. nov. is elevated to full species rank;the species has a wide distribution from central and southern Vietnam across Cambodia to eastern Thailand;we regard Lygosoma vittigerum kronfanum Smith, 1922 and Leiolopisma pranensis Cochran, 1930 as its junior synonyms;(3) Lipinia trivittata sp. nov. occurs in hilly areas of southern Vietnam, Cambodia, and eastern Thailand;and (4) Lipinia vassilievi sp. nov. is currently known only from a narrow area along the Vietnamese-Cambodian border in the foothills of the central Annamite Mountain Range. We further provide an identification key for Lipinia occurring in mainland Southeast Asia.

关键词： Lipinia microcercus stat. nov. Lipinia trivittata sp. nov. Lipinia vassilievi sp. nov. Vietnam, Thailand, Cambodia Biogeography mtDnA COI-barcoding

Effects of Substrate Pulse Bias Duty Cycle on the Microstructure and Mechanical Properties of Ti–Cu–n Films Deposited by Magnetic Field-Enhanced Arc Ion Plating

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Acta Metallurgica Sinica(English Letters) 2017年第2期30卷 176-184页

作者： Sheng-Sheng Zhao Yan-Hui Zhao Lv-Sha Cheng Vladimir Viktorovich Denisov nikolay nikolaevich Koval Bao-Hai Yu Hai-Juan Mei School of Mechanical and Electrical Engineering Shenzhen Polytechnic Institute of Metal Research Chinese Academy of Sciences Institute of High Current Electronics Siberian BranchRussian Academy of Sciences

Ti–Cu–n films were deposited on 316 L stainless steel substrates by magnetic field-enhanced arc ion *** effect of substrate pulse bias duty cycle on the chemical composition,microstructure,surface morphology,mechanical and tribological properties of the films was systemically *** results showed that,with increasing the duty cycle,Cu content decreases from 3.3 to 0.58 at.%.XRD results showed that only Ti n phase is observed for all the deposited films and the preferred orientation transformed from Ti n（200） to Ti n（111） plane with the increase in duty *** surface roughness and deposition rate showed monotonous decrease with increasing the duty *** residual stress and hardness firstly increase and then decrease afterwards with the increase in duty cycle,while the variation of critical load shows reverse *** for the film with duty cycle of 10%,others perform the better wear resistance.

关键词： Magnetic field Arc ion plating Ti-Cu-n film Residual stress Hardness

Discovery of Japalura chapaensis Bourret,1937(Reptilia:Squamata:Agamidae)from Southeast Yunnan Province,China

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Zoological Research 2018年第2期39卷 105-113页

作者： Kai Wang Ke Jiang Yu-Fan Wang nikolay A.Poyarkov Jr. Jing Che Cameron D.Siler Sam noble Oklahoma Museum of natural History & Department of Biology University of Oklahoma Kunming Institute of Zoology Chinese Academy of Sciences Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Zhejiang Forest Resource Monitoring Center Department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University

Due to a paucity of surveys in northern Indochina and lack of international collaborations among neighboring countries, recognized distributional ranges for many amphibian and reptile species end at the political borders for some countries, despite seemingly continuous suitable habitat spanning the region. Combining both morphological and genetic data, we report the first discovery of Japalura chapaensis, a rare agamid lizard believed previously to be endemic to northern Vietnam only, along the border region of southeastern Yunnan Province,China. To facilitate future research on the genus Japalura sensu lato in Indochina, we provide detailed descriptions of additional specimens of this rare species, including the first description of coloration in life and an expanded diagnosis, and discuss the species boundary of J. chapaensis with respect to its congeners.

关键词： Draconinae Indochina Morphological Variation new record Range extension Systematics Taxonomy

new variable stars from the photographic archive:semi-automated discoveries,attempts at automatic classification and the new field 104 Her

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Research in Astronomy and Astrophysics 2018年第8期18卷 29-40页

作者： Sergei V.Antipin Ignacio Becker Alexander A.Belinski Darya M.Kolesnikova Karim Pichara nikolay n.Samus Kirill V.Sokolovsky Alia V.Zharova Alexandra M.Zubareva P.K.Sternberg Astronomical Institute M.V.Lomonosov Moscow University13University Ave.Moscow 119234Russia Pontificia Universidad Catolica de Chile SantiagoChile Institute of Astronomy Russian Academy of Sciences48Pyatnitskaya Str.Moscow 109017Russia Institute for Applied Computational Science Harvard UniversityCambridgeMAUSA IAASARS National Observatory of Athens15236 PenteliGreece Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str.84/32Moscow 117997Russia

Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute （Lomonosov Moscow University） in 1976-1994 and digitized with a resolution of 2400dpi, we dis- covered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type re- main not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys.

关键词： techniques photometric

Optimization of an Underwater Wireless Sensor network Architecture with Wave Glider as a Mobile Gateway

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Journal of Marine Science and Application 2022年第2期21卷 179-196页

作者： Tatiana A.Fedorova Vladimir A.Ryzhov nikolay n.Semenov Shaharin A.Sulaiman Department of Applied Mathematics and Mathematical Modeling Saint-Petersburg State Marine Technical University3 LotsmanskayaSaint Petersburg 190121Russia Department of Marine Information Systems and Technologies Saint-Petersburg State Marine Technical University3 LotsmanskayaSaint Petersburg 190121Russia Department of Mechanical Engineering Universiti Teknologi PETRONAS32610 Seri IskandarMalaysia

This paper presents an original probabilistic model of a hybrid underwater wireless sensor network(UWSn),which includes a network of stationary sensors placed on the seabed and a mobile *** mobile gateway is a wave glider that collects data from the underwater network segment and retransmits it to the processing *** authors consider the joint problem of optimal localization of stationary network nodes and the corresponding model for bypassing reference nodes by a wave *** optimality of the network is evaluated according to the criteria of energy efficiency and *** influence of various physical and technical parameters of the network on its energy efficiency and on the lifespan of sensor nodes is *** analysis is carried out for networks of various scales,depending on the localization of stationary nodes and the model of bypassing the network with a wave *** a model example,the simulation of the functional characteristics of the network for a given size of the water area is carried *** is shown that in the case of a medium-sized water area,the model of“bypassing the perimeter”by a wave glider is practically feasible,energy efficient and reliable for hourly data *** the case of a large water area,the cluster bypass model becomes more efficient.

关键词： Underwater wireless sensor network(UWSn) Wave glider(WG) Sensor network architecture Mobile gateway Hydroacoustic communication

Classical Dynamics of Muonic-Electronic Helium and Heliumlike Ions: The Allowance for the Eccentricity of the Muon and nucleus Orbits

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Open Journal of Microphysics 2021年第3期11卷 27-36页

作者： nikolay Kryukov Eugene Oks Universidad nacional Autónoma de México Av. Universidad Ciudad Universitaria Coyoacán México Mexico Physics Department Auburn University Auburn AL USA

In the previous paper by one of us (hereafter paper I), the author considered Rydberg states of the muonic-electronic helium atom or helium-like ion and used the fact that the muon motion occurs much more rapidly than the electron motion. Assuming that the muon and nucleus orbits are circular, he applied the analytical method based on separating rapid and slow subsystems. He showed that the electron moves in an effective potential that is mathematically equivalent to the potential of a satellite orbiting an oblate planet like the Earth. He also showed that the “unperturbed” elliptical orbit of the electron engages in two precessions simultaneously: the precession of the electron orbit in the plane of the orbit and the precession of the orbital plane of the electron around the axis perpendicular to the plane of the muon and nuclear orbits. The problem remained whether or not the allowance for the ellipticity of the orbit could significantly change the results. In the present paper, we address this problem: we study how the allowance for a relatively low eccentricity ε of the muon and nucleus orbits affects the motion of the electron. We derive an additional, ε-dependent term in the effective potential for the motion of the electron. We show analytically that in the particular case of the planar geometry (where the electron orbit is in the plane of the muon and nucleus orbits), it leads to an additional contribution to the frequency of the precession of the electron orbit. We demonstrate that this additional, ε-depen- dent contribution to the precession frequency of the electron orbit can reach the same order of magnitude as the primary, ε-independent contribution to the precession frequency. Therefore, the results of our paper seem to be important not only qualitatively, but also quantitatively.

关键词： Muonic-Electronic Helium Muonic-Electronic Helium-Like Ions Rydberg States Role of the Eccentricity of the Muon Orbit Precession of the Electron Orbit

Risk score for predicting abdominal complications after coronary artery bypass grafting

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World Journal of Cardiology 2020年第10期12卷 492-500页

作者： Dmitry Vladimirovich Belov Dmitry Victorovich Garbuzenko Ksenia Alekseevna Abramovskikh nikolay Olegovich Arefyev Department of Hospital Surgery Federal Center of Cardiovascular Surgery of the Ministry of Health of Russia(the city of Chelyabinsk)Chelyabinsk 454003Russia Department of Faculty Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Hospital Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Pathological Anatomy and Forensic Medicine South Ural State Medical UniversityChelyabinsk 454092Russia

BACKGROUnD Although early abdominal complications after coronary artery bypass grafting(CABG)with cardiopulmonary bypass(CPB)are rare,the associated mortality remains *** To develop a risk score for the prediction of early abdominal complications after CABG with *** This retrospective study was performed in the Federal State Budgetary Establishment“Federal Center of Cardiovascular Surgery”of the Ministry of Health of Russia(the city of Chelyabinsk)and included data of 6586 patients who underwent CABG with CPB during *** risk factors taken for evaluation were compared between patients with early abdominal complications(n=73)and without them(n=6513).We identified the most important risk factors and their influence on the development of early abdominal complications after CABG with *** Gender and the presence of postinfarction cardiosclerosis,chronic kidney disease,or diabetes in the anamnesis did not affect the occurrence of abdominal *** leading risk factors of the early abdominal complications after CABG with CPB were multifocal atherosclerosis,extracorporeal membrane oxygenation,intra-aortic balloon pump,atrial fibrillation,perioperative myocardial infarction,and the need for resternotomy in the postoperative *** average value of the predicted probability was 0.087±0.015 in patients with early abdominal complications after CABG with CPB and 0.0094±0.0003 in patients without these *** percentage of correct classification turned out to be 98.9%.After calculating a score for each of the leading risk factors,we counted a total score for each particular *** highest risk was noted in patients with a total score of 7 or *** The developed score predicts the risk of early abdominal complications after CABG with CPB and makes it possible to stratify patients by risk groups.

关键词： Coronary artery bypass grafting Cardiopulmonary bypass Abdominal complications Risk factors Risk score

Methods and Devices of Speckle-noise Suppression (Review)

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Optics and Photonics Journal 2020年第10期10卷 219-250页

作者： Igor Kompanets nikolay Zalyapin Quantum Radiophysics Division P.N. Lebedev Physical Institute Moscow Russia

Speckles in images formed by a laser beam are interference noise arising due to coherent nature of laser radiation. As the number of projection systems using laser light sources increases, new methods and devices appear for reducing the contrast of speckle-noise and thereby suppressing it. Taking into account the long-standing nature of the problem and the continuing relevance of its solution, this review discusses modern practical methods and devices—despecklers, used to reduce the speckle contrast and to achieve high quality of projected images. The review discusses the nature of the speckles appearance, considers their statistical properties, and describes the measurement of the speckle contrast. The requirements for despecklers are considered, the most important of which are speckle suppression efficiency, simplicity of design and compactness, low power consumption and low optical loss. The characteristics of different types of despecklers, including diffusers, devices based on electroactive polymers, optical waveguides, colloidal solutions and liquid crystals, as well as orthogonal phase matrices and diffraction gratings proposed as despeckers, are examined in detail. It is shown that despecklers with decorrelation of the phase front based on the mirror deformation and optical fiber have less light losses. Electro-optical-liquid crystal despecklers do not have mechanically deformable or moving elements that reduce the reliability and durability of operation, and are more compact and simple in design. A comparative table of characteristics of the most effective despecklers in which the speckle contrast is reduced to ten percent or less, with an indication of their advantages and disadvantages, is given.

关键词： Projection System Laser Beam Speckle-noise Speckle Suppression