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Reduction Theorems for Principal and Classical Connections

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Acta mathematica Sinica,English Series 2010年第1期26卷 169-184页

作者： miroslav DOUPOVEC Wlodzimierz m. mIKULSKI Department of mathematics Brno University of Technology Institute of mathematics Jagiellonian University

We prove general reduction theorems for gauge natural operators transforming principal connections and classical linear connections on the base manifold into sections of an arbitrary gauge natural bundle. Then we apply our results to the principal prolongation of connections. Finally we describe all such gauge natural operators for some special cases of a Lie group G.

关键词： Gauge natural operator reduction theorem principal prolongation

Oxidation state specific analysis of arsenic species in tissues of wild-type and arsenic(+3 oxidation state)methyltransferase-knockout mice

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Journal of Environmental Sciences 2016年第11期28卷 104-112页

作者： Jenna m.Currier Christelle Douillet Zuzana Drobná miroslav Styblo Curriculum in Toxicology University of North Carolina at Chapel Hill Department of Nutrition Gillings School of Global Public Health University of North Carolina at Chapel Hill

Arsenic methyltransferase（As3mt） catalyzes the conversion of inorganic arsenic（i As） to its methylated metabolites, including toxic methylarsonite（mAs~Ⅲ） and dimethylarsinite（DmAs~Ⅲ）. Knockout（KO） of As3 mt was shown to reduce the capacity to methylate i As in mice. However, no data are available on the oxidation states of As species in tissues of these mice. Here, we compare the oxidation states of As species in tissues of male C57BL/6 As3mt-KO and wild-type（WT） mice exposed to arsenite（iA s~Ⅲ） in drinking water. WT mice were exposed to50 mg/L As and As3mt-KO mice that cannot tolerate 50 mg/L As were exposed to 0, 15, 20, 25 or30 mg/L As. iA s~Ⅲaccounted for 53% to 74% of total As in liver, pancreas, adipose, lung, heart, and kidney of As3mt-KO mice; tri- and pentavalent methylated arsenicals did not exceed 10% of total As. Tissues of WT mice retained iA s and methylated arsenicals： iA s~Ⅲ, mAs~Ⅲand DmAs~Ⅲ represented 55%‐68% of the total As in the liver, pancreas, and brain. High levels of methylated species, particularly mAs~Ⅲ, were found in the intestine of WT, but not As3mt-KO mice,suggesting that intestinal bacteria are not a major source of methylated As. Blood of WT mice contained significantly higher levels of As than blood of As3mt-KO mice. This study is the first to determine oxidation states of As species in tissues of As3mt-KO mice. Results will help to design studies using WT and As3mt-KO mice to examine the role of iA s methylation in adverse effects of iA s exposure.

关键词： Arsenic speciation analysis Hydride generation-cryotrapping-atomic absorption spectrometry Arsenic(+ 3 oxidation state) methyltransferase As3mt knockout mice

A model for strong attenuation and dispersion of seismic P-waves in a partially saturated fractured reservoir

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Science China(Physics,mechanics & Astronomy) 2010年第8期53卷 1383-1387页

作者： BRAJANOVSKI miroslav müLLER Tobias m PARRA Jorge O Department of Exploration Geophysics Curtin University of Technology Geophysical Institute University of Karlsruhe Southwest Research Institute

In this work we interpret the data showing unusually strong velocity dispersion of P-waves (up to 30%) and attenuation in a relatively narrow frequency range. The cross-hole and VSP data were measured in a reservoir, which is in the porous zone of the Silurian Kankakee Limestone Formation formed by vertical fractures within a porous matrix saturated by oil, and gas patches. Such a medium exhibits significant attenuation due to wave-induced fluid flow across the interfaces between different types of inclusions (fractures, fluid patches) and background. Other models of intrinsic attenuation (in particular squirt flow models) cannot explain the amount of observed dispersion when using realistic rock properties. In order to interpret data in a satisfactory way we develop a superposition model for fractured porous rocks accounting also for the patchy saturation effect.

关键词： attenuation dispersion Biot’s slow wave poroelasticity fractures patchy-saturation

Bellman Systems with mean Field Dependent Dynamics

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Chinese Annals of mathematics,Series B 2018年第3期39卷 461-486页

作者： Alain BENSOUSSAN miroslav BULICEK Jens FREHSE Jindal School of management International Center for Decision and Risk Analysis University of Texas at Dallas800 W.Campbell RdSM 30 RichardsonTX 75080-3021USA Department SEEm City University of Hong Kong Hung HomKowloonHong KongChina mathematical Institute Faculty of Mathematics and PhysicsCharles UniversitySokolovska 8318675 Praha 8Czech Republic Institute for Applied mathematics Department of Applied AnalysisEndenicher Allee 6053115 BonnGermany

The authors deal with nonlinear elliptic and parabolic systems that are the Bellman like systems associated to stochastic differential games with mean field dependent *** key novelty of the paper is that they allow heavily mean field dependent *** in particular leads to a system of PDE's with critical growth,for which it is rare to have an existence and/or regularity *** the paper,they introduce a structural assumptions that cover many cases in stochastic differential games with mean field dependent dynamics for which they are able to establish the existence of a weak *** addition,the authors present here a completely new method for obtaining the maximum/minimum principles for systems with critical growths,which is a starting point for further existence and also qualitative analysis.

关键词： Stochastic games Bellman equation mean field equation Nonlinearelliptic equations Weak solution maximum principle

Host preference of the major strains of Plum pox virus--Opinions based on regional and world-wide sequence data

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Journal of Integrative Agriculture 2017年第3期16卷 510-515页

作者： Nina Sihelská miroslav Glasa Zdeno W Subr Biomedical Research Center Institute of Virology Slovak Academy of Sciences Bratislava 84505 Slovak Republic

Plum pox virus（PPV）causes sharka-the most serious viral disease of stone fruit *** is wide spread in Europe and mediterranean Basin,its incidence has been further approved in Asia and both *** PPV strains have been recognized until now（PPV-D,PPV-m,PPV-Rec,PPV-EA,PPV-C,PPV-T,PPV-W,PPV-CR,and PPV-An）,forming molecularly distinct entities,however,only partially differentiable by their biological or epidemiological *** most strict virus-host linkages under natural conditions have been detected for strains naturally infecting cherries（PPV-C and PPV-CR）.However,although less stringent but still clear host preference is observed also for three epidemiologically most important strains（PPV-D/plum/apricot,PPV-m/peach,and PPV-Rec/plum）.So far no genetic marker has been mapped in the PPV genome,which responsibility for the host specificity/preference could be explicitly *** this review,we focus on the host preference of three major PPV strains as evidenced by analysis of an extensive dataset of PPV isolates of Slovak and world-wide ***,we discuss several performed relevant experiments and further possible research procedures aimed to better understand the genetic determinants and mechanisms of the host preference of this potyvirus.

关键词： sharka Prunus virus-host interactions

Hybrid Power Supply System with Fuzzy Logic Controller: Power Control Algorithm, main Properties, and Applications

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Journal of modern Power Systems and Clean Energy 2022年第4期10卷 923-931页

作者： Dragana J.Petrović miroslav m.Lazić Bojana V.JovanovićLazić Branko D.Blanuša Stanko O.Aleksić Department of Power Electronics Iritel a.d.BelgradeBelgradeSerbia Department of Power Electronics Faculty of Electrical Engineering University of Banja LukaBanja LukaSerbian

This paper presents a novel power supply system based on the use of fuzzy inference logic to improve the power control of renewable energy *** system comprises renewable solar and wind sources,and an accumulator battery is used as an additional power *** procedure for the parallel connection of multiple energy sources provides a stable power supply and optimal charging of the accumulative *** energy sources are connected in parallel using two serial converters and controlled by the controller based on the fuzzy *** reference voltage control of the serial converter enables an optimal use of available energy *** accumulative element is connected in parallel to compensate for the shortage of solar and wind energies,whereas if the available renewable energy exceeds the needs of the consumers,the surplus energy is accumulated in the *** measurements are conducted on the prototype of the hybrid power system under real conditions and compared with the applied systems of this *** novel system is mainly used in remote telecom locations where there is no power distribution network.

关键词： Fuzzy logic hybrid power source power supply parallel operation serial converter

Zinc deficiency in patients with chronic pancreatitis

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World Journal of Gastroenterology 2019年第5期25卷 600-607页

作者： miroslav Vujasinovic AleksANDra Hedstr?m Patrick maisonneuve Roberto Valente Henrik von Horn J-matthias L?hr Stephan L Haas Department for Digestive Diseases Karolinska University Hospital Division of Epidemiology and Biostatistics IEO European Institute of Oncology IRCCS Department for Digestive Diseases Sapienza University of Rome Division of Clinical Chemistry Department of Molecular Medicine and Surgery Karolinska Institutet Karolinska University Hospital Department of Clinical Science Intervention and Technology (CLINTEC)Karolinska Institute

BACKGROUND Zinc is a key element in numerous proteins and plays an important role in essential cell functions such as defense against free radicals and DNA damage repair. Chronic pancreatitis(CP) is a chronic inflammation with progressive fibrosis of pancreas ultimately resulting in pancreatic exocrine insufficiency(PEI),which is associated with malnutrition. Studies analyzing zinc levels in patients with CP are sparse and lead to conflicting *** To investigate serum zinc levels in patients with CP of various *** Between October 2015 and march 2018, patients with a diagnosis of CP were identified and recruited from the Pancreatic Outpatient Clinic at the Karolinska University Hospital in Stockholm, Sweden. Demographic, clinical and laboratory data were analyzed. Etiology of CP was determined according to the mANNHEIm classification system into the following etiological subcategories:alcohol consumption, nicotine consumption, hereditary factors, efferent pancreatic duct factors and immunological factors. Pancreatic exocrine function was defined as normal(fecal elastase 1 > 200 μg/g), mildly reduced(100-200μg/g) and severely reduced(fecal elastase 1 mol/L) was present in 39(26.0%) of patients: 22 females and 17 males. In the group of patients with zinc deficiency, 76.7% of patients had an exocrine pancreatic insufficiency(FE-1 mpared to patients 0.002]. Smoking and number of packyears were additionally associated with low zinc levels. The risk of zinc deficiency in current smokers and smokers with ≥ 20 pack-years was approximately three times higher

关键词： Zinc Pancreas Pancreatic exocrine insufficiency Chronic pancreatitis malnutrition

Pesticide-induced photoluminescence quenching of ultra-small Eu3+-activated phosphate and vanadate nanoparticles

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Journal of materials Science & Technology 2020年第3期38卷 197-204页

作者： Jovana Perisa Zeljka Antic Chong-Geng ma Jelena Papan Dragana Jovanovic miroslav D.Dramicanin Vinca Institute of Nuclear Sciences University of BelgradeP.O.Box 52211001 BelgradeSerbia College of Sciences Chongqing University of Posts and TelecommunicationsChongqing 400065China

The aim of this research was to investigate the luminescent behavior of ultra-small Eu3+-activated phosphate and vanadate nanoparticles in the presence of *** have an average diameter of approximately 2 nm with a narrow size *** monazite crystal structure of phosphate-based particles(space group P121/n1)and single tetragonal zircon-type structure of vanadate-based particles(space group of I41/amd)have been confirmed using X-ray diffraction *** synthesized Eu3+-activated colloidal nanoparticles show sharp emission peaks in the red spectral *** measurements revealed emission quenching upon addition of millimolar concentrations of following pesticides:4-Chloro-2-methyl-phenoxyacetic acid(mCPA),2,4-Dichlorophenoxyacetic acid(2,4-D)and N-(phosphonomethyl)glycine(Glyphosate).In both phosphate and vanadate-based colloidal nanoparticles luminescence quenching is more evident in the presence of 2,4-D pesticide with the lowest limit of detection(0.7μm)obtained for phosphate-based nanoparticles.

关键词： Phosphate/vanadate based colloidal nanoparticles Eu3+ Emission quenching Pesticide

Case of rectal angioleiomyoma in a female patient

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World Journal of Gastroenterology 2013年第13期19卷 2114-2117页

作者： Goran Z Stanojevi Dragan S mihailovi milica D Nestorovi milan D Radojkovi milan m Jovanovi miroslav P Stojanovi Branko B Brankovi General Surgery Clinic Ni Clinical CentreFaculty of MedicineUniversity of Ni18000 NiSerbia Institute of Pathology NiClinical CentreFaculty of MedicineUniversity of Ni18000 NiSerbia

Angioleiomyoma represents a benign stromal tumor, which usually occurs in the subcutaneous tissue of the extremities, although its occurrence in the gastrointestinal tract is very rare. A case of rectal angioleiomyoma in a 40 year-old female patient is described here. Six months earlier, the patient suffered from periodical prolapse of an oval tumor from the anus, along with difficulties in bowel movement. A transanal extirpation of the tumor was performed. This is the first reported case in the English literature of a patient presenting with prolapsed angioleiomyoma of the rectum. During the immediate postoperative period, as well as 6 mo later, the patient had an unremarkable postoperative recovery.

关键词： Prolapsed tumor Angioleiomyoma Rectum Leiomyoma