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High frequency of latent Chlamydia trachomatis infection in patients with rhegmatogenous retinal detachment

International Journal of Ophthalmology(English edition) 2016年第6期9卷 863-868页

作者： Ernest V.Bolko Alexei L.Pozniak Dmitrii s.Maltsev Alexei A.suetov Irina V.Nuralova st.petersburg branch of the academician s.fyodorov irtc "Eye Microsurgery"St.Petersburg 192283Russia Department of Ophthalmology Military Medical AcademySt.Petersburg 194044Russia

AIM： To determine the frequency of detection of ocular and extraocular Chlamydia trachomatis （CT） infection in non -high myopes with rhegmatogenous retinal detachment （RRD）. METHODs： This was a single-center, nonrandomized, prospective, case-control study. One hundred and four patients were divided into a study group with RRD （n= 63） and a control group with traumatic retinal detachment （n=41）. samples of subretinal fluid （sFR）, conjunctival, urethral/cervical swabs, and blood were collected. The frequency of detection of CT infection in sRF samples was determined by polymerase chain reaction （PCR）, direct fluorescence assay （DFA） and cell culture, whereas that in conjunctival swabs was determined by PCR and DFA, and those in urethral/cervical swabs and blood were determined by DFA. Yates Chi-square test （with Bonferroni correction） and two-tailed student＇s t-test were used for statistical analysis. REsULTs： sRF CT infection was detected more frequently in the study group （50.8%-71.4%） than in the control group （9.8%-12.2%） by all the methods used （P〈 0.01）. The frequency of detection of conjunctival CT infection by DFA was higher in the RRD patients compared with the controls （81.0% vs 24.4%, P=0.004）. The PCR detected conjunctival CT infection more often in the study group than in the controls （46.0% vs89.8%, P= 0.007）. The DFA detected CT in blood specimens almost as frequently as in urogenital specimens, for the RRD patients （61.2% vs 63.5%） and the controls （7.3% vs 9.8%）. CONCLUsION： CT infection is detected with high frequency in non-high myopes with RRD.

关键词： rhegmatogenous retinal detachment Chlamydia trachomatis myopia latent infection

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Effect of synthesis conditions and surrounding medium on luminescence properties of YVO_4:Eu^(3+) nanopowders

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Journal of Rare Earths 2015年第2期33卷 129-134页

作者： E.V.Golyeva D.V.Tolstikova I.E.Kolesnikov M.D.Mikhailov st.petersburg state Polytechnical University St.Petersburg 195251 Russia scientific and Technological Institute of Optical Material science VNTs S.I.Vavilov State Optical InstituteSt.Petersburg 192171 Russia st.petersburg state University St.Petersburg 199034 Russia

Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500℃, t1=1 h; Т2=950 ℃, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. It was found that the observed lifetime of YVO4：Eu^3＋ 5 at.% nanophosphor was decreased from 0.64 ms in air（nmed=1） to 0.45 ms in chalcogenide glass As39s61（nmed=2.39）.

关键词： nanopowders rare earths luminescence effective refractive index lifetime

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Photoluminescence properties of Eu3+-doped MgAl2O4 nanoparticles in various surrounding media

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Journal of Rare Earths 2019年第8期37卷 806-811,I0001页

作者： I.E.Kolesnikov E.V.Golyeva E.V.Borisov E.Yu Kolesnikov E.Lahderanta A.V.Kurochkin M.D.Mikhailov st.petersburg state University St.PetersburgRussia Lappeenranta University of Technology LUT LappeenrantaFinland Peter the Great st.petersburg Polytechnic University St.PetersburgRussia scientific and Technological Institute of Optical Material science VNTs S.I.Vavilov State Optical InstituteSt.PetersburgRussia Volga state University of Technology Yoshkar-OlaRussia

Eu3+-doped MgAl2O4 nanoparticles were prepared by modified Pechini method.X-ray diffraction analysis shows pure tetragonal spinel phase without any *** average size of synthesized nanoparticles was determined to be about 50-60 nm using scanning electron microscopy and static light scattering *** and excitation spectra as well as lifetimes of MgAl2O4:Eu3+ nanophosphors were explored in surrounding media with different refractive *** medium does not affect luminescence bands position,whereas 5D0 lifetime monotonically decreases along with increase of medium refractive *** of surrounding media on radiative and nonradiative decay rates,which were calculated using 4f-4f intensity theory,was studied and *** factor of prepared nanoparticles is defined using both radiative and observed lifetimes.

关键词： Eu3+ Nanoparticles Filling factor Luminescence Lifetime Rare earths

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Impact of drilling waste pollution on land cover in a high subarctic forest-tundra zone

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Pedosphere 2022年第3期32卷 414-425页

作者： Anatoly OPEKUNOV Marina OPEKUNOVA stepan KUKUsHKIN sergey LIsENKOV Institute of Earth sciences St.Petersburg State UniversitySt.Petersburg 199178(Russia)

Global climate changes can lead to the destruction of the permafrost zone and contribute to the active transfer of pollutants to natural *** can be especially pronounced in the areas of oil and gas production in the *** study aimed to define the landscape components(i.e.,groundwater,soil water,soil,and indicator plant species)of chemical pollution with metals,oil hydrocarbons,and polycyclic aromatic hydrocarbons,from the discharge of drill *** at two sites in the forest-tundra zone of Western siberia(Russia)were carried out within two years of *** migration was found in peaty-gley heavy loamy soils and iron-illuvial clayey podburs,but lateral migration of different pollutants did not exceed 200 ***,radial migration was practically absent owing to the high buffering capacity of the soil organic horizon and the upward flow of matter in the seasonal melt *** main indicators of drilling waste pollution were high concentrations of sr,Ba,petroleum hydrocarbons,and Cl^(-)*** the waste disposal sites,the concentration of Ba and sr in the soil water were 1150 and 1410μg L^(-1),respectively;in groundwater,they reached 721 and 2360μg L^(-1),*** the soil,Ba and sr accumulated in the peaty horizon(798 and 706 mg kg^(-1),respectively).The concentration of Cl^(-)ions in the soil water at the site of waste discharge was 1912 mg L^(-1),and at a distance of 200 m,it decreased to 77.4 mg L^(-1).The Cl^(-)concentration in the groundwater was lower,and at a distance of 200 m,it was 38.9 mg L^(-1).The highest concentration of petroleum hydrocarbons in the surface layer was found in the peaty-gley soils(up to 2400 mg kg^(-1)).In glandular-illuvial podburs,it was 420 mg kg^(-1).In horizons BH and BC,it was close to the background values(27 and 33 mg kg^(-1),respectively).Alkalinization of soils and water under the influence of drill cuttings led to the death of oligotrophic and acidophilic vegetation at a distanc

关键词： metal petroleum hydrocarbons plant indicator species pollutant migration in soil polycyclic aromatic hydrocarbon

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Composite Biomaterials Based on Poly(L-Lactic Acid)and Functionalized Cellulose Nanocrystals

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Journal of Renewable Materials 2020年第4期8卷 383-395页

作者： Mariia stepanova Ilia Averianov Olga solomakha Natalia Zabolotnykh Iosif Gofman Mikhail serdobintsev Tatiana Vinogradova Viktor Korzhikov-Vlakh Evgenia Korzhikova-Vlakh Institute of Macromolecular Compounds Russian Academy of SciencesSt.Petersburg199004Russia st.petersburg Research Institute of Phthisiopulmonology St.Petersburg194064Russia Institute of Chemistry Saint-Petersburg State UniversitySt.Petersburg199034Russia

The biocomposite films were prepared from poly(L-lactic acid)and cellulose *** improve interfacial compatibility of hydrophilic cellulose nanocrystals with hydrophobic matrix polymer as well as to provide the osteoconductive properties,cellulose was functionalized with poly(glutamic acid).The modified cellulose nanocrystals were better distributed and less aggregated within the matrix,which was testified by scanning electron,optical and polarized light *** to mechanical tests,composites filled with nanocrystals modified with PGlu demonstrated higher values of Young’s modulus,elongation at break and tensile *** of composite materials in model buffer solutions for 30 weeks followed with staining of Ca^(2+)deposits with Alizarin Red s assay testified better mineralization of materials containing PGlu-modified cellulose nanocrystals as *** the result of in vivo experiment,the developed composite materials showed less level of inflammation in comparison with pure polymer matrix and composites filled with non-functionalized cellulose nanocrystals.

关键词： Biomaterials polymer composites biodegradable and biocompatible polymers poly(L-lactic acid) cellulose nanocrystals modification

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Influence of dust particles on spatial distributions of particles and fluxes in positive column of glow discharge

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Plasma science and Technology 2019年第11期21卷 45-54页

作者： Ruihuan TIAN Chengxun YUAN Dmitrii V BOGDANOV Evgeniy A BOGDANOV Anatoly A KUDRYAVTsEV Zhongxiang ZHOU Department of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China Faculty of Physics St.Petersburg State University198504St.PetersburgRussia

The research herein examined the results of numerical simulations of the positive column of a glow discharge in argon dusty plasma using COMsOL Multiphysics software under conditions similar to the project known as *** scenarios dealing with formations of spatial distributions of densities and fluxes for charged particles were studied,and evaluations of the influence of dust particles on the discharge were obtained in a wide range of dust *** extreme cases were distinguished:weak dust influence when the densities,fluxes and electric field profiles are not perturbed,and strong dust influence when all three density profiles(electrons,ions and charged dust)in the dust cloud are similar(parallel)to each other,resulting in all created charges in the dust cloud being lost inside the *** such a case,the ambipolar field and the transport of charged particles are decreased in the dust cloud,and any ambipolar flux is almost absent within the cloud.

关键词： dusty plasma glow discharge kinetics modeling scaling laws

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What Mice Can Teach Us about How to stop Drug-Resistant Tuberculosis:Correct Chemotherapy Regimen and Patient Compliance are the Key

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Biomedical and Environmental sciences 2024年第9期37卷 1086-1090页

作者： Igor Mokrousov Tatiana Vinogradova Marine Dogonadze Maria Vitovskaya Natalia Zabolotnykh sergei Chekrygin Anna Vyazovaya Laboratory of Molecular Epidemiology and Evolutionary Genetics St.Petersburg Pasteur InstituteSt.Petersburg197101Russia Henan International Joint Laboratory of Children’s Infectious Diseases Children’s Hospital Affiliated to Zhengzhou UniversityHenan Children’s Hospital Zhengzhou Children’s HospitalZhengzhou 450012HenanChina st.petersburg Research Institute of Phthisiopulmonology St.PetersburgRussia Resource Center Bio-bank Center Research Park of St.Petersburg State UniversitySt.PetersburgRussia

Despite well-known limitations,mice remain useful as model animals to study tuberculosis(TB)pathogenesis,the basic immune response,the extent of lung pathology as well as efficacy of new drugs against Mycobacterium tuberculosis[1,2].There are four routes of tuberculosis infection in mice:aerosol generation and exposition,intravenous injection,intranasal administration,and subcutaneous administration[3].

关键词： tuberculosis drugs injection

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Zircon U-Pb Geochronology Recorded Late Cretaceous Fluid Activation in the Central Aldan Gold Ore District, Aldan shield, Russia: First Data

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Journal of Earth science 2020年第3期31卷 481-491页

作者： Vasilii I.Leontev sergey G.skublov Nadezhda V.shatova Alexey V.Berezin Faculty of Geological Prospecting Saint Petersburg Mining University199106 St.PetersburgRussia Institute of Precambrian Geology and Geochronology of Russian Academy of sciences 199034 St.PetersburgRussia Karpinsky Russian Geological Research Institute 199106 St.PetersburgRussia Institute of Earth science St.Petersburg State University199034 St.PetersburgRussia

The gold mineralization in the Central Aldan ore district is genetically related to potassic calc-alkaline and alkaline magmatism dated at 115–150 *** objective of this study is to establish the age of hydrothermal processes that accompanied the formation of Au-Te mineralization at the samolazovsky *** on the isotope-geochemical study of zircons from quartz-feldspar metasomatic rocks of the deposit,the granitoids and charnokites of the Nimnyr Complex(1900–1960 Ma)at the contact with the Yukhta monzonite-syenite massif(~127 Ma)were *** U-Pb dating was performed on a sHRIMP-II ion microprobe,and rare-earth and trace elements analyses of zircon were carried out in the same craters by secondary-ion mass spectrometry on a Cameca IMs-4f ion *** is revealed that the studied zircons have heterogeneous structures:dark core and lighter rim,which differ greatly in isotope-geochemical *** rims are cut by a network of fractures,extending into the central part of zircon *** rims yield a subconcordant age of 1937±24 Ma,with an average total REE content of 550 ppm,which corresponds to the formation age of the Nimnyr *** zircon cores yield a discordant age of 83±11 Ma and are characterized by a higher total REE content(~1812 ppm),as well as higher contents of U and non-formula elements(Ca,sr,and Y)with respect to rims,due to the effect of fluid on *** the limited number of zircon grains,the additional geochronological study of zircons from syenites of the ore-bearing Ryabinovy Massif has revealed the presence of two distinct age clusters:~125–138 and 76–83Ма.The older ages of zircons from syenites are typical for the Central Aldan ore *** now,there is still no explanation for an age range(76–83 Ma)of single zircon grains from ore-bearing syenites of the Ryabinovy *** obtained data suggest that the processes of activation(the effect of fluid)within the Central Aldan ore district continued unt

关键词： U-Pb geochronology REE geochemistry zircon samolazovskoe Deposit Ryabinovoe Deposit Aldan shield

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Model of tunnelling through periodic array of quantum dots in a magnetic field

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Chinese Physics B 2012年第11期21卷 412-415页

作者： I.Yu.Popov s.A.Osipov st.petersburg National Research University of Information Technologies Mechanics and OpticsKronverkskiy49St.Petersburg 197101Russia

A two-dimensional periodic array of quantum dots with two laterally coupled leads in a magnetic field is considered. The model of electron transport through the system based on the theory of self-adjoint extensions of symmetric operators is suggested. We obtain the formula for the transmission coefficient and investigate its dependence on the magnetic field.

关键词： tunnelling nanostructure operator extension theory

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On the possible orbital motion of sgr A* in the smooth potential of the Milky Way

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Research in Astronomy and Astrophysics 2020年第12期20卷 383-390页

作者： Igor’I.Nikiforov Angelina V.Veselova st.petersburg state University Universitetskij Prospekt 28Staryj PeterhofSt.Petersburg 198504Russia

The modern accuracy of measurements allows the residual/peculiar(Galactocentric) velocity of the supermassive black hole(sMBH) in our Galaxy, sgr A*, on the order of several kilometers per *** integrate possible orbits of the sMBH along with the surrounding nuclear stellar cluster(NsC) for a barred model of the Galaxy using modern constraints on the components of the sMBH Galactocentric velocity. Is is shown that the range of oscillations of the sMBH + NsC in a regular Galactic field in the plane of the Galaxy allowed by these constraints strongly depends on the set of central components of the Galactic potential. If the central components are represented only by a bulge/bar, for a point estimate of the sMBH Galactocentric velocity, the oscillation amplitude does not exceed 7 pc in the case that a classical bulge is present and reaches 25 pc if there is no bulge;with sMBH velocity components within the 2σ significance level, the amplitude can reach 15 and 50 pc, respectively. However, when taking into account the nuclear stellar disk(NsD), even in the absence of a bulge, the oscillation amplitude is only 5 pc for the point estimate of the sMBH velocity, and 10 pc for the 2σ significance level. Thus, the possible oscillations of the sMBH + NsC complex from the confirmed components of the Galaxy’s potential are mostly limited by the NsD, and even taking into account the uncertainty of the mass of the latter, the oscillation amplitude can hardly exceed 13 pc = 6′.

关键词： Galaxy:center Galaxy:fundamental parameters Galaxy:kinematics and dynamics

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