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Interpenetrated Magnesium-Tricalcium Phosphate Composite:Manufacture,Characterization and In Vitro Degradation Test

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 319-325页

作者： Mariano Casas-Luna Serhii Tkachenko miroslava horynova Lenka Klakurkova Pavel Gejdos Sebastian Diaz-de-la-Torre Ladislav Celko Jozef Kaiser Edgar B. Montufar CEITEC-Central European Institute of Technology Brno University of TechnologyPurkyfnova 656/123612 00 BmoCzech Republic CIITEC-Centro de Investigacion e Innovacion Tecnologica Instituto Politocnico NacionalCerrada de CECATI02250 Mexico CityMexico

Magnesium and calcium phosphates composites are promising biomaterials to create biodegradable load-bearing implants for bone regeneration. The present investigation is focused on the design of an interpenetrated magnesium- tricalcium phosphate （Mg-TCP） composite and its evaluation under immersion test. In the study, TCP porous preforms were fabricated by robocasting to have a prefect control of porosity and pore size and later infiltrated with pure commercial Mg through current-assisted metal infiltration （CAMI） technique. The microstructure, composition, distribution of phases and degradation of the composite under physiological simulated conditions were analysed by scanning electron microscopy, elemental chemical analysis and X-ray diffraction. The results revealed that robocast TCP preforms were full infiltrated by magnesium through CAMI, even small pores below 2 μm have been filled with Mg, giving to the composite a good interpenetration. The degradation rate of the Mg-TCP composite displays lower value compared to the one of pure Mg during the first 24 h of immersion test.

关键词： Calcium phosphate Magnesium Liquid metal infiltration Spark plasma sintering Corrosion

Conformally flat, minimal, Lagrangian submanifolds in complex space forms

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Science China Mathematics 2022年第8期65卷 1641-1660页

作者： miroslava Antić Luc Vrancken Faculty of Mathematics University of BelgradeBelgrade 11000Serbia Laboratoire de Mathématiques pour l’Ingénieur Université Polytechnique Hauts-de-FranceValenciennes 59313France Departement Wiskunde Katholieke Universiteit LeuvenLeuven 3001Belgium

We investigate n-dimensional(n≥4),conformally flat,minimal,Lagrangian submanifolds of the n-dimensional complex space form in terms of the multiplicities of the eigenvalues of the Schouten tensor and classify those that admit at most one eigenvalue of multiplicity *** the case where the ambient space is Cn,the quasi umbilical case was studied in Blair(2007).However,the classification there is not complete and several examples are ***,we complete(and extend) the classification and we also deal with the case where the ambient complex space form has non-vanishing holomorphic sectional curvature.

关键词： Lagrangian submanifolds conformally flat complex space form warped product submanifold

Characterization of Totally Geodesic Totally Real 3-dimensional Submanifolds in the 6-sphere

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1557-1564页

作者： miroslava ANTIC Mirjana DJORIC Luc VRANCKEN Faculty of Mathematics University of BelgradeStudentski trg 16 pb. 550 11000 Belgrade Serbia and Montenegro LAMATH ISTV2 Université de Valenciennes Campus du Mont Houy59313 Valenciennes Cedex 9 France

In this paper, we study Lagrangian submanifolds of the nearly Kaehler 6-sphere. We derive a pinching result for the Ricci curvature of such submanifolds thus providing a characterisation of the totally geodesic subman... 详细信息

关键词： Ricci curvature totally real submanifold nearly Kaehler 6-sphere totally geodesic submanifold

Boron Oxide Glasses and Nanocomposites: Synthetic, Structural and Statistical Approach

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Journal of Materials Science & Technology 2017年第6期33卷 535-540页

作者： Hristo Hristov miroslava Nedyalkova Sergio Madurga Vasil Simeonov Faculty of Chemistry and Pharmacy University of Sofia Physical Chemistry Department and Research Institute of Theoretical and Computational Chemistry (IQTCUB) of the University of Barcelona (UB)

Three different precursors of boron-aqua and glycerol solutions of boric acid and ethanol solution of trimethyl borate were used for the preparation of organic–inorganic advanced materials. The films and bulk materials samples were heat treated at 100, 400, 800？C for 2 h. The hybrid samples were stable and transparent until 100？C. The further increase of temperature to 400？C led to destruction of samples, and at 800？C they were molten. The structural changes during the pyrolysis were studied by Fourier transform infrared spectroscopy, differential thermal analysis, and X-ray diffraction. Details of surface morphology were observed by scanning electron microscopy. The obtained BO_3 and BO_4 groups were identified in the molten materials after pyrolysis. The quantities and order of borate structural units as well as residual carbon in the networks depended on boron precursor type. PVA/PEG/B_2O_3 hybrid materials were proved to be appropriate precursors for synthesizing borate and carboborate glass and carbon/borate glass nanocomposites. To access the impact of the experimental conditions on the structural changes of the nanocomposites, cluster analysis of the IR-spectral data was used as a classification method.

关键词： Organic–inorganic hybrid materials Borate glass Nanocomposites Cluster analysis

Effect of Osmotic Stress in Early Stages of Ontogenesis on Root Respiration, Growth, Sugar Content,and Cell Injury in Maize Seedlings Differing in Drought Sensitivity

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Journal of Integrative Plant Biology 2006年第7期48卷 814-822页

作者： Lukás, Kolarovic miroslava Luxová Peter Valentovic Institute of Botany Slovak Academy of Sciences Dubravská cesta 14 Bratislava 84523 Slovakia

Cultivars of maize （Zea mays L.） with different sensitivity to drought were exposed to 0.3 mol/L sorbitol （-1.4 MPa water potential） for 24 h. Exposure to water deficiency significantly reduced the growth of both shoots （coleoptile and hypocotyl） and roots. Shoot growth was inhibited more than the growth of roots. Osmotic stress enhanced accumulation of soluble sugars. Electrolyte leakage, a cell injury index, was slightly increased after 0.3 mol/L sorbitoh Respiration was measured in the presence and absence of 2,6-dlchloro-phenol indophenoh 2,6-Dichloro-phenol indophenol did not influence respiration rates, because statistically equal results were observed under both conditions. Total respiration （VT） decreased after osmoticum treatment. There were no significant differences in the VT among the cultlvars analysed. The decrease In VT was caused by a decline In the activities and capacities of both cytochrome （Vcyt, Vcyt） and alternative pathway （Valt, Valt） of respiration. A high residual respiration （Vres） was observed, up to 27% of total uninhibited respiration. The result of uncoupler use clearly indicated that coupling was maintained after 24 h of osmotic stress. The recovery of the respiration rate was comparable with that of non-stressed control rates. According to these observations, no possible mltochondrial damage is expected. Water deficiency did not induce a stimulation of the alternative oxidase, so we assume that the stimulation of the alternative pathway is not related to drought stress resistance; rather, the function of the alternative pathway is to balance carbon metabolism and electron transport in a response to a changing environment.

关键词： alternative oxidase (AOX) alternative respiration 2,6-dichloro-phenol indophenol (DCPIP) maize osmotic stress sugars uncoupler.

Response of Growth Dynamics of Two Spring Geophytes to Light Regime in a Lime-Beech Forest

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Journal of Integrative Plant Biology 2006年第5期48卷 527-535页

作者： Zorica Popovic Aleksandar Mijovic Branko Karadzic miroslava Mijatovic Institute of Biological Research Department of Ecology Despota Stefana Boulevard 142 11060 Belgrade Serbia and Montenegro Environment Protection Agency Ministry for Science and Environmental Protection Republic of Serbia Serbia and Montenegro

Blomaee accumulation, leaf longevity and growth rate of two spring forest geophytes, Scllla blfolla L. and Arum maculatum L. were estimated separately for three size groups within each population of these species. Despite the differences in leaf longevity, both species showed a similar pattern of blomass accumulation In relation to their phenologles and reproductive demands. Eco-physlological acclimation to changing light environment was assumed through photosynthetic parameters and dynamics of leaf area Index In the predominant size group of each species. A light response curve was measured under natural light for each species through the continuum of Its phenology to quantify the photosynthetic photon flux density at light saturation, light-saturated photosynthetic rate, light compensation point, and dark respiration. Light-saturated assimilation per leaf area basis, dark respiration rate and light compensation points were significantly higher in S. blfolla relative to A. maculatum. However, the acclimation of photosynthesis that would respond to light changes in environment was not found in S. bifolla. In contrast, In A. maculatum a marked shift In the light dependence of photosynthesis through the season was noticed, which resulted In a strong photosynthetic acclimation to the low-light conditions. Accompanied by significant leaf area Index, this efficient low-light photosynthesis enabled greater leaf longevity, and consequently longer accumulative period to A. maculatum. From the different parameters that we determined （both photosynthetic acclimation and growth strategy） it would appear that these species belong to two distinct subgroups： S. blfolla to the early and A. maculatum to the late vernals.

关键词： biomass accumulation deciduous forests early and late vernals leaf area index (LAI) light response of photosynthesis spring geophytes.

Lanthanide complexes with β-diketones and coumarin derivates:synthesis,thermal behaviour,optical and pharmacological properties and immobilisation

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Journal of Rare Earths 2010年第S1期28卷 66-74页

作者： Maria Milanova Joana Zaharieva Iliya Manolov miroslava Getzova Dimitr To dorovsky Department of Inorganic Chemistry University of SofiaBulgaria 1J. Bourc hier Blvd.1164 SofiaBulgaria Department of Organic Chemistry Medical Un iversity2Dunav Str.1000 SofiaBulgaria

The paper presents the results of the synthesis of complexes of the ty pe Eu(DBM) 3 and Eu(DBM) 3·Q(DBM-dibenzoylmethane,Q-1,10-phenantroline or 4,7-d iphenyl-1,10-phenantroline) and of Tb-and Nd-complexes with the newly-synthesis ed coumarin derivates 3,3’-[(4-chlorphenyl) methylene) bis(4-hydroxy-2H-chromen-2-one) ,3,3’-[(3,5-dimethoxy-4-hydroxy) methylene) bis(4-hydroxy-2H-chromen-2-one) ,etc. Elemental and thermogravimetric analysis,IR,UV,NMR and fluorescence spe ctroscopy and X-ray analysis were applied for characterisation of the complexes. Some peculiarities of the synthetic procedures for both types of complexes were discussed and the influence of the synthetic approach,pH of the reaction mediu m,temperature of synthesis and drying of the complexes on the composition,stab ility and optical properties was reported. The immobilisation of the complexes i n thin films based on sol-gel produced SiO2 and on polymethylmethacrylate was st udied. The optimal conditions for preparation of the matrices(composition of th e starting system,temperature and time of sol aging,etc.) were recommended. Th e film morphology was evaluated by fluorescence,scanning electron and atomic fo rce microscopy. The interaction of the lanthanide ions with the matrices and the influence of their nature,the effect of the in-situ polymerisation and other f actors on photoluminescent excitation and emission spectra and excited state lif e-times of the complexes were followed. The effect of the second ligand on the p hotoluminescence properties of the immobilised diketonates was further elucidate d. Processes involved in the thermal decomposition of the complexes and microcom posites produced on their base were proposed. Preliminary results on the pharmac ological properties of the coumarin complexes reported showed unambiguously high er cytotoxicity of the Nd complex in comparison with that of the respective ligand.

关键词： rare earths complexes thin films β-diketones coumarin derivates optical properties pharmacological properties morphology

Comparison and analysis of the efficacy of drug therapy for liver cancer

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Hepatoma Research 2020年第9期6卷 55-64页

作者： Philippe Merle miroslava Subic Unitéd’Hépatologie et Gastroentérologie Hôpital de la Croix RousseHospices Civils de LyonLyon 69004France. Centre de Recherche en Cancérologie de Lyon INSERM U1052Lyon 69003France. UniversitéClaude Bernard Lyon 1 Villeurbanne 69100France

Hepatocellular carcinoma(HCC)is a poor prognosis tumor when not accessible to potentially curative treatments such as surgical resection,thermal ablations or liver *** cytotoxic chemotherapies have shown inconsistent clinical *** 2007,sorafenib,a tyrosine kinase inhibitor(TKI),was the first systemic therapy able to significantly improve the outcome of HCC patients non-eligible for curative or loco-regional therapies,despite a modest tolerance and low tumor objective response rate(ORR).Among the newer TKIs approved after 2017,lenvatinib was the first to show a striking ORR and demonstrate non-inferiority *** in the first-line ***,phase 3 trials showed the benefit of other TKIs,regorafenib and cabozantinib,and the anti-angiogenic ramucirumab monoclonal antibody,in systemic second-line *** checkpoint inhibitors targeting PD1,achieved striking tumor shrinkage in some patients in monotherapy,seeming to be associated with exciting ***,this occurred in too few patients to improve the median overall *** recently,the combination of anti-angiogenic drugs targeting the liver microenvironment with PD-1/PD-L1 inhibitors,such as the combination of bevacizumab and atezolizumab,proved to be substantially effective in phase 3,and other combinations of PD-1/PD-L1 and CTLA-4 inhibitors or TKIs have raised a lot of hopes for the systemic treatment of HCC.

关键词： Hepatocellular carcinoma therapy immune checkpoint inhibitors tyrosine kinase inhibitors

Molecular heterogeneity of gelatin-binding proteins from human seminal plasma

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Asian Journal of Andrology 2010年第3期12卷 363-375,I0010页

作者： Maja M. Kosanovic miroslava M. Jankovic Department for Immunochemistry and Glycobiology Institute for the Application of Nuclear Energy-INEP University of Belgrade Banatska 31b Zemun-Belgrade 11080 Serbia

Defining the molecular characteristics of seminal plasma proteins is essential for understanding their function in physiological and pathological conditions. Starting from the predicted importance of human seminal plasma gelatin-binding proteins, comprising fibronectin （FN） and FN-related molecules, for male fertility, this study aims at gaining insight into their immuno-glycobiochemical properties. Human seminal plasma from subjects with normal semen parameters were separated on a gelatin-Sepharose column and analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis and immunoblotting using antibodies against distinct FN forms. Heterogeneity of the isolated molecular species was examined by protein chip arrays combined with surface-enhanced laser desorption/ionization time of flight mass spectrometry, on normal, metal and hydrophobic surfaces. Carbohydrate composition was investigated using mannose-, fucose- and sialic acid-specific plant lectins and galectin-1. The results obtained indicated a pattern of isolated proteins corresponding to that of known FN fragments, as confirmed by immunoreactivity. Among them heparin-binding ability was preferentially associated with low molecular mass species. As for posttranslational modifications, phosphorylation and glycosylation of distinct fragments were revealed. Lectin binding to fragments containing the gelatin-binding domain, particularly with Ricinus communis agglutinin I, was stronger than to fragments containing the cell-binding site of FN. A low level of sialylation and distinctive concanavalin A- and Lens culinaris agglutinin-reactive species were also observed. Galectin-1 did not interact with the isolated preparation. Resolving the molecular heterogeneity of normal human seminal plasma FN and gaining initial insight into possible similarities/differences with known FN molecular species may be considered a prerequisite step preceding challenging the clinical usefulness of these molecular properties.

关键词： fibronectin gelatin-binding glycosylation heparin-binding human seminal plasma