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Estimating masses of selected stars in the Pulkovo program by means of astrometry methods

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Research in Astronomy and Astrophysics 2018年第8期18卷 45-52页

作者： Natalia A.Shakht Denis l.Gorshanov olga O.Vasilkova Central(Pulkovo)Astronomical Observatory of Russian Academy of Sciences Saint Petersburg196140 Russia

Stars in the Pulkovo Observatory program are observed with a 65-cm refractor during many years to study their positions and movements. We present examples of two visual binary stars, for which orbits and masses of components were determined, and two astrometric stars, for which masses of their unseen companions were estimated. The first two stars are ADS 14636 （61 Cygni） and ADS 7251, and the others are Gliese 623 and ADS 8035 （Alpha Uma）. Direct astrometric methods are used for estimation of mass-ratio and masses.

关键词： stellar masses - orbits - binaries individual (61 Cygni Alpha Uma Gliese 623 ADS 7251)

Patent foramen ovale closure in non-lacunar cryptogenic ischemic stroke:where are we now?

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Journal of Geriatric Cardiology 2021年第1期18卷 67-74页

作者： AdriàARBOIX olga PARRA Josefina AlIÓ Cerebrovascular Division Department of NeurologyHospital Universitari del Sagrat CorUniversitat de BarcelonaBarcelonaCataloniaSpain Department of Pneumology Hospital Universitari del Sagrat CorUniversitat de BarcelonaBarcelonaCataloniaSpain Department of Cardiology Hospital Universitari de BellvitgeL’Hospitalet de LlobregatBarcelonaCataloniaSpain

Patent foram ovale(PFO)is the most common anatomical cause of an interarterial *** is usually asymptomatic but may cause paradoxical embolism and is a risk factor for non-lacunar cryptogenic cerebral ischemia in young *** the first clinical trials did not show a significant superiority of PFO closure in the secondary prevention of cerebral ischemia as compared with standard antithrombotic treatment,six subsequent randomized clinical trials(ClOSURE I,PC Trial,RESPECT,ClOSE,REDUCE,and DEFENSE-PFO)performed in a sample of cryptogenic stroke in patients aged 60 years or younger provided evidence of a significant reduction of recurrent cerebral ischemia after percutaneous PFO ***,the use of percutaneous PFO closure cannot be generalized to the entire population of patients with cerebral ischemia and PFO,but it is indicated in highly selected patients with non-lacunar cryptogenic cerebral infarction with a large right-to-left shunt,an atrial septal aneurysm and no evidence of atrial fibrillation,as well as in association with antithrombotic treatment for an optimal secondary prevention of cerebral ischemia.

关键词： PFO Patent foramen ovale closure in non-lacunar cryptogenic ischemic stroke where are we now

Retina stem cells,hopes and obstacles

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World Journal of Stem Cells 2021年第10期13卷 1446-1479页

作者： olga.l.German Harmonie Vallese-maurizi Tamara B Soto Nora P Rotstein luis Enrique Politi Department of Biology Biochemistry and PharmacyUniversidad Nacional del SurBahia blanca 8000Buenos AiresArgentina Department of Biology Biochemistry and PharmacyUniversidad Nacional del Surand Neurobiology DepartmentInstituto de Investigaciones Bioquímicas de Bahía Blanca(INIBIBB)ConicetBahía Blanca 8000Buenos AiresArgentina

Retinal degeneration is a major contributor to visual dysfunction *** it comprises several eye diseases,loss of retinal pigment epithelial(RPE)and photoreceptor cells are the major contributors to their *** therapies included diverse treatments,such as provision of anti-vascular endothelial growth factor and many survival and trophic factors that,in some cases,slow down the progression of the degeneration,but do not effectively prevent *** finding of stem cells(SC)in the eye has led to the proposal of cell replacement strategies for retina *** using different types of SC,such as retinal progenitor cells(RPCs),embryonic SC,pluripotent SCs(PSCs),induced PSCs(iPSCs),and mesenchymal stromal cells,capable of self-renewal and of differentiating into multiple cell types,have gained ample *** preclinical studies have assessed transplantation of SC in animal models,with encouraging *** aim of this work is to revise the different preclinical and clinical approaches,analyzing the SC type used,their efficacy,safety,cell attachment and integration,absence of tumor formation and immunorejection,in order to establish which were the most relevant and *** addition,we examine the questions and concerns still open in the *** data demonstrate the existence of two main approaches,aimed at replacing either RPE cells or *** evidence suggests that RPCs and iPSC are the best candidates,presenting no ethical concerns and a low risk of *** trials have already supported the safety and efficacy of SC *** concerns are pending,such as the risk of tumor formation,lack of attachment or integration of transplanted cells into host retinas,immunorejection,cell death,and also ***,the amazing progress in the field in the last few years makes it possible to envisage safe and effective treatments to restore vision loss in a near future.

关键词： Retina regeneration Stem cells Retina stem cell transplantation Cancer stem cells Photoreceptor replacement

GC-NICI-MS analysis of acetazolamide and other sulfonamide (R-SO2-NH2)drugs as pentafluorobenzyl derivatives [R-SO2-N(PFB)2] and quantification of pharmacological acetazolamide in human urine

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Journal of Pharmaceutical Analysis 2020年第1期10卷 49-59页

作者： olga Begou Kathrin Drabert Georgios Theodoridis Dimitrios Tsikas Institute of Toxicology Core Unit ProteomicsHannover Medical SchoolCarl-Neuberg-Strasse 1D-30625HannoverGermany Department of Chemistry Aristotle University of Thessaloniki54124ThessalonikiGreece BIOMIC_AUTh Center for Interdisciplinary Research and Innovation(CIRI-AUTH)Balkan Center10th Km Thessaloniki-Thermi RdP.O.Box 8318GR 57001ThessalonikiGreece

Acetazolamide(molecular mass(MM),222)belongs to the class of sulfonamides(R-SO2-NH2)and is one of the strongest pharmacological inhibitors of carbonic anhydrase *** is excreted unchanged in the ***,we report on the development,validation and biomedical application of a stable-isotope dilution GC-MS method for the reliable quantitative determination of acetazolamide in human *** method is based on evaporation to dryness of 50 ml urine aliquots,base-catalyzed derivatization of acetazolamide(d0-AZM)and its internal standard[acetylo-2H3]acetazolamide(d3-AZM)in 30 vol%pentafluorobenzyl(PFB)bromide in acetonitrile(60 min,30C),reconstitution in toluene(200 ml)and injection of 1-ml *** negative-ion chemical ionization(NICI)mass spectra(methane)of the PFB derivatives contained several intense ions including[M]‒at m/z 581 for d0-AZM and m/z 584 for d3-AZM,suggesting derivatization of their sulfonamide groups to form N,N-dipentafluorobenzyl derivatives(R-SO2-N(PFB)2),i.e.,d0-AZM-(PFB)2 and d3-AZM-(PFB)2,*** was performed by selected-ion monitoring of m/z 581 and 83 for d0-AZM-(PFB)2 and m/z 584 and 86 for d3-AZM-(PFB)*** limits of detection and quantitation of the method were determined to be 300 fmol(67 pg)and 1 mM of acetazolamide,***-and inter-assay precision and accuracy for acetazolamide in human urine samples in pharmacologically relevant concentration ranges were determined to be 0.3%e4.2%and 95.3%e109%,*** method was applied to measure urinary acetazolamide excretion after ingestion of a 250 mg acetazolamide-containing tablet(Acemit®)by a healthy *** other tested sulfonamide drugs,methazolamide(MM,236)was also found to form a N,N-dipentafluorobenzyl derivative,whereas dorzolamide(MM,324)was hardly *** GC-MS peaks were obtained from the PFB bromide derivatization of hydrochlorothiazide(MM,298),xipamide(MM,355),indapamide and metholazone(MM,366 each)or br

关键词： Acetazolamide Derivatization Quantification Sulfonamides Validation

The presence of ANP in rat peritoneal mast cells

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Cell Research 2005年第10期 65-70页

作者： marina G maRTYNOVA,olga A BYSTROVA,olga M MOISEEVA,Anton l EVDONIN,Kirill A KONDRATOV,Natalja D MEDVEDEVA Institute of Cytology Russian Academy of Sciences St. Petersburg 196064 Russia Institute of Cytology Russian Academy of Sciences St. Petersburg 196064 Russia Almazovs’ Research Institute of Cardiology St. Petersburg 194056 Russia Institute of Cytology Russian Academy of Sciences St. Petersburg 196064 Russia Institute of Cytology Russian Academy of Sciences St. Petersburg 196064 Russia Institute of Cytology Russian Academy of Sciences St. Petersburg 196064 Russia

Atrial natriuretic peptide (ANP) is an important component of the natriuretic peptide system. A great role in many regulatory systems is played by mast cells. Meanwhile involvement of these cells in ANP activity is poorly studied. In this work, we have shown the presence of ANP in rat peritoneal mast cells. Pure fraction of mast cells was obtained by separation of rat peritoneal cells on a Percoll density gradient. By Western blotting, two ANP-immunoreactive proteins of molecular masses of 2.5 kDa and 16.9 kDa were detected in lysates from these mast cells. Electron microscope immunogold labeling has revealed the presence of ANP-immunoreactive material in storage, secreting and released granules of mast cells. Our findings indicate the rat peritoneal mast cells to contain both ANP prohormone and ANP. These both peptides are located in mast cell secretory granules and released by mechanism of degranulation. It is discussed that many mast cell functions might be due to production of natriuretic peptides by these cells.

关键词： natriuretic peptide system secretory granules ANP-immunoreactivity proANP.

A simple method to model the reduced environment of lake bottom sapropel formation

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Chinese Journal of Oceanology and limnology 2017年第4期35卷 956-966页

作者： olga.l.GASKOVA Vera D.STRAKHOVENKO Nadezhda I.ERMOlAEVA Eugene Yu.ZARUBINA Ekaterina A.OVDINA V.S.Sobolev Institute of Geology and Mineralogy Siberian Branch of the Russian Academy of Sciences Novosibirsk State University Institute for Water and Environmental Problems Siberian Branch of the Russian Academy of Sciences

The Kambala and Barchin brackish lakes （Baraba steppe, southern West Siberia） contain an organic-rich sapropel layer that was formed in oxygen-depleted waters. We measured the bulk sediment elemental composition, the water chemistry and determined the mineralogical composition and predominant biota species （Diatoms and Cyanobacteria in phytoplankton community respectively） in the lakes. The result indicates that the first lake has a siliceous type of sapropel and the second a carbonaceous one. A computer thermodynamic model was developed for chemical interaction in water-bottom sediment systems of the Kambala and Barchin lakes. The surface sodium bicarbonate waters are supersaturated with respect to calcite, magnesite （or low Mg-calcite）, quartz and chlorite with minor strontianite, apatite and goethite （pH 8.9-9.3, Eh 0.3 V）. Nevertheless, it is shown that during sapropel deposition, deep silt waters should be anoxic （Eh〈0 V）. The virtual component CH20 has been used to create an anoxic environment suitable for pyrite formation due to the biotic community impact and abiotic reduction. Thermodynamic calculation has shown that silt water is not necessarily euxinic （anoxic and sulfidic）. Depending on Eh, sulfate sulfur can dominate in solution, causing the formation of gypsum together with pyrite. An attempt was made to find a reason for solution supersaturation with respect to Ca and Mg ions due to their complexation with humic acids.

关键词： brackish lakes sapropel sediments mineral composition silica calcite thermodynamic calculations

Clearcuts and related secondary dieback undermine the ecological effectiveness of FSC certification in a boreal forest

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Ecological Processes 2020年第1期9卷 108-116页

作者： Jeanette Silvin Blumröder Monika T.Hoffmann olga Ilina Susanne Winter Peter R.Hobson Pierre l.Ibisch Centre for Econics and Ecosystem management Eberswalde University for Sustainable DevelopmentAlfred-Moeller-Str.116225 EberswaldeGermany Petrozavodsk State University Lenina st.33185000 PetrozavodskRussia Karelian Nature Conservancy(SPOK) PetrozavodskRussia WWF Germany Reinhardtstr1810117 BerlinGermany Centre for Econics and Ecosystem management Writtle University CollegeLordship RoadWrittle Chelmsford Essex CM13RRUK

Background:Over the last 25 years,the prominent forest certification system established by the Forest Stewardship Council(FSC)has used by many companies worldwide for claiming responsible forest *** objectives of the Russian National FSC standard to decrease the size of clearcuts and the retention of forest elements such as residual seed trees need on-site validation to proof the effectiveness of *** assess the ecological impacts of harvesting practices and benefits of FSC certification,we geospatially compared logging activities with and without FSC *** a sample area covering approximately 3,000 km^(2) in the east of the Russian Arkhangelsk Region,we used available data on tree cover loss and satellite images to assess secondary impacts of clearcuttings on adjacent remnant forests and to quantify the logging ***,the size and structure as well as the density of skidding trails of ten specific clearcuttings located within the sample area were surveyed using satellite images and in the field observation to delineate the boundaries of clearcuts and forested remnants within the ***:We found a significant increase of small-scale tree cover loss in the proximity of the *** dieback is possibly linked to the scale and intensity of logging in the *** the investigated clearcuts,FSC failed to reduce the size,to increase the retention of forest remnants including seed trees on logged areas,and to maintain larger tracts of undisturbed ground and soil compared to clearcuts that were logged before they received ***:Trees and forest remnants remaining inside an increasingly stressed forest ecosystem matrix may not resist further harvesting-related and climate change-induced stresses and ***-scale clearcuttings seem to have negative impacts even in adjacent forests and undermine the ecological effectiveness of FSC certification in the study *** Russi

关键词： Ecological effectiveness Impact assessment Forest certification Sustainable forestry

The structural basis of oscillation damping in plant stems-biomechanics and biomimetics

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Journal of Bionic Engineering 2004年第3期1卷 149-158页

作者： Hanns-Christof Spatz Anton Emanns olga Speck Competence Network Biomimetics Plant Biomechanics Group Fakultt für Biologie Albert-Ludwigs-Universitt Freiburg Schnzlestr. 1 D –79104 Freiburg GermanyCompetence Network Biomimetics Plant Biomechanics Group Fakultt für BiologieAlbert-Ludwigs-Universitt Freiburg Schnzlestr. 1 D –79104 Freiburg GermanyCompetence Network Biomimetics Plant Biomechanics Group Fakultt für BiologieAlbert-Ludwigs-Universitt Freiburg Schnzlestr. 1 D –79104 Freiburg Germany

Oscillations and their damping were investigated for plant stems of Cyperus alternifolius l., Equisetum hyemale l., Equisetum fluviatile l., Juncus effuses l., Stipa gigantea link, and Thamnocalamus spathaceus (Franch.) Soderstr. With the exception of T. spathaceus, mechanical damping of the oscillation of individual plant stems, even without side organs, leaves or inflorescences, is quite effective. Our experiments support the hypothesis that embedding stiff sclerenchymatous elements in a more compliant parenchymatous matrix provides the structural basis for the dissipation of mechanical energy in the plant stem. As an application the naturally occurring structures were mimicked in a compound material made from hemp fabrics em- bedded in polyurethane foam, cured under pressure. like its natural model it shows plastic deformability and viscoelastic be- haviour. In particular the material is characterized by a remarkably high shock absorption capacity even for high impact loads.

关键词： biomechanics biomimetics compound materials damped oscillations plants shock absorption viscoelasticity.

Variation in abundance and habitat relationship of three understory insectivorous birds in a disturbed landscape of Neotropical dry forest of Colombia

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Avian Research 2020年第3期11卷 265-276页

作者： Camilo loaiza olga.l.ontenegro David King manuel Spínola lilibeth Arinda Palacio Agustín Rudas Instituto de Ciencias Naturales Universidad Nacional de ColombiaBogotáColombia Northern Research Station USDA Forest ServiceUniversity of Massachusetts204 Holdsworth HallAmherstMA 01003USA Instituto Internacional en Conservación y manejo de Vida Silvestre Universidad NacionalApartado1350-3000 HerediaCosta Rica.

Background:Evaluating relationships between avian populations and their habitat is important for understanding the biology of these species and for management decisions that improve the effectiveness of restoration *** investigated how habitat variation along a disturbance gradient affected the abundance of three insectivorous bird species,White-bellied Antbird(Myrmeciza longipes),Barred Antshrike(Thamnophilus doliatus),and Pale-breasted Spinetail(Synallaxis albescens)in a Neotropical dry forest remnant in central ***:The study area,which is located in magdalena Valley,is under ecological restoration after the construction of the“El Quimbo”hydroelectric dam,with a gradient of habitat conditions,from relatively advanced secondary growth to recently disturbed *** conducted bird surveys and quantified the habitat conditions from June 2018 to June *** compared the relative abundance of the birds among the three zones with increasing disturbance and modeled the relationship between the bird abundance with the micro-and landscape-habitat conditions,with Poisson generalized linear model ***:The relative abundance of the three bird species varied according to the habitat features and disturbance *** abundance of White-bellied Antbirds was higher in forests and thickets than shrubland fragments;Barred Antshrike was more abundant in shrubland and thickets than in forest fragments,and Pale-breasted Spinetail had the highest abundance in shrubland and the lowest in forest *** abundance of both White-bellied Antbird and Pale-breasted Spinetail did not differ among zones with different levels of disturbance,while the abundance of Barred Antshrike decreased in zones with more ***:There were significant differences in the habitat relationships of the three understory insectivorous species along the disturbance gradient,although these species were within the same trophic *** bird species prefer

关键词： Bird population ecology Generalized linear models Wildlife habitat restoration