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Matter and Radiation at Extremes 2019年第6期4卷 37-43页

作者： Yan-Jun Gu Martin Jirka ondrej Klimo Stefan Weber Institute of Physics of the ASCR ELI-BeamlinesNa Slovance 218221 PragueCzech Republic Institute of Plasma Physics of the CAS Za Slovankou 1782/318200 PragueCzech Republic FNSPE Czech Technical University in Prague11519 PragueCzech Republic School of Science Xi’an Jiaotong UniversityXi’an 710049 China

High-energyγ-photon generation via nonlinear Compton scattering and electron–positron pair creation via the Breit–Wheeler process driven by laser–plasma interaction are modeled,and a number of mechanisms are proposed.Owing to the small cross section,these processes require both an ultra-intense laser field and a relativistic electron bunch.The extreme conditions for such scenarios can be achieved through recent developments in laser technology.Photon emission via nonlinear Thomson and Compton scattering has been observed experimentally.Highenergy positron beams generated via a multiphoton process have recently been observed too.This paper reviews the principles ofγ-ray emission and e+e−pair creation in the context of laser–plasma interaction.Several proposed experimental setups forγ-ray emission and e+e−pair creation by ultra-intense laser pulses are compared in terms of their efficiency and the quality of theγ-photon and positron beams produced for ultrashort(15 fs)and longer(150 fs)multi-petawatt laser beams.

关键词： interaction. positron intense

FEM Study of the Strain Kinematics in the 3D Nanofibrous Structure Prepared by the Electrospinning Process

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Applied Mathematics 2013年第5期4卷 80-90页

作者： Michal Petru ondrej Novak David Vejrych Petr Lepsik Institute for Nanomaterials Advanced Technologies and InovationTechnical University of LiberecLiberecCzech Republic Department of Nonwovens Technical University of LiberecLiberecCzech Republic Department of Machine Elements and Mechanism Technical University of LiberecLiberecCzech Republic

Finite element model (FEM) was used for the study and description of the arising 3D nanofiber structure strain caused by the pressure of the flowing gas. Computer simulation using an adaptive networking through implicit FEM algorithm can be utilized for a significant improvement of the study of anisotropic strain in the deformed 3D nanostructure. The created model is based on the empirical Laplace-Poisson differential equation for the flow, where gas particles are moving with certain kinetic energy. The kinetic energy depends on the speed, time and temperature and affects the resulting strain of 3D nanofiber structure. The simulation results were compared to the results obtained from the image analysis of real samples and showed that this FEM model can determine individual phases of structure strain. The comparison shows that the developed FEM model can be an important tool in the study of the strain in the arising 3D nano- fiber structure and it can provide valuable information for optimization of 3D nanofiber structure production by the electrospinning process.

关键词： FEM Strain 3D Nanofibrous Structure Electrospinning Gas Flow

Deep learning analysis of defect and phase evolution during electron beam-induced transformations in WS_(2)

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npj Computational Materials 2019年第1期5卷 1039-1046页

作者： Artem Maksov ondrej Dyck Kai Wang Kai Xiao David B.Geohegan Bobby G.Sumpter Rama K.Vasudevan Stephen Jesse Sergei V.Kalinin Maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37831USA Bredesen Center for Interdisciplinary Research University of TennesseeKnoxvilleTN 37996USA Computational Sciences&Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

Recent advances in scanning transmission electron microscopy(STEM)allow the real-time visualization of solid-state transformations in materials,including those induced by an electron beam and temperature,with atomic resolution.However,despite the ever-expanding capabilities for high-resolution data acquisition,the inferred information about kinetics and thermodynamics of the process,and single defect dynamics and interactions is minimal.This is due to the inherent limitations of manual ex situ analysis of the collected volumes of data.To circumvent this problem,we developed a deep-learning framework for dynamic STEM imaging that is trained to find the lattice defects and apply it for mapping solid state reactions and transformations in layered WS_(2).The trained deep-learning model allows extracting thousands of lattice defects from raw STEM data in a matter of seconds,which are then classified into different categories using unsupervised clustering methods.We further expanded our framework to extract parameters of diffusion for sulfur vacancies and analyzed transition probabilities associated with switching between different configurations of defect complexes consisting of Mo dopant and sulfur vacancy,providing insight into pointdefect dynamics and reactions.This approach is universal and its application to beam-induced reactions allows mapping chemical transformation pathways in solids at the atomic level.

关键词： defect beam sulfur

Mapping mesoscopic phase evolution during E-beam induced transformations via deep learning of atomically resolved images

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npj Computational Materials 2018年第1期4卷 396-404页

作者： Rama K.Vasudevan Nouamane Laanait Erik M.Ferragut Kai Wang David B.Geohegan Kai Xiao Maxim Ziatdinov Stephen Jesse ondrej Dyck Sergei V.Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37831USA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Quantum Computing Institute Oak Ridge National LaboratoryOak RidgeTN 37831USA UnitedHealth Group PO Box 1459Minneapolis 55440 MNUSA

Understanding transformations under electron beam irradiation requires mapping the structural phases and their evolution in real time.To date,this has mostly been a manual endeavor comprising difficult frame-by-frame analysis that is simultaneously tedious and prone to error.Here,we turn toward the use of deep convolutional neural networks(DCNN)to automatically determine the Bravais lattice symmetry present in atomically resolved images.A DCNN is trained to identify the Bravais lattice class given a 2D fast Fourier transform of the input image.Monte-Carlo dropout is used for determining the prediction probability,and results are shown for both simulated and real atomically resolved images from scanning tunneling microscopy and scanning transmission electron microscopy.A reduced representation of the final layer output allows to visualize the separation of classes in the DCNN and agrees with physical intuition.We then apply the trained network to electron beam-induced transformations in WS2,which allows tracking and determination of growth rate of voids.We highlight two key aspects of these results:(1)it shows that DCNNs can be trained to recognize diffraction patterns,which is markedly different from the typical“real image”cases and(2)it provides a method with inbuilt uncertainty quantification,allowing the real-time analysis of phases present in atomically resolved images.

关键词： beam evolution atomic

Microbial communities biostimulated by ethanol during uranium （VI） bioremediation in contaminated sediment as shown by stable isotope probing

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Frontiers of Environmental Science & Engineering 2015年第3期9卷 453-464页

作者： Mary Beth LEIGH Wei-Min WU Erick CARDENAS ondrej UHLIK Sue CARROLL Terry GENTRY Terence L. MARSH Jizhong ZHOU Philip JARDINE Craig S. CRIDDLE James M. TIEDJE Center for Microbial Ecology Michigan State University East Lansing MI 48824 USA Institute of Arctic Biology University of Alaska Fairbanks Fairbanks AK 99775 USA Department of Civil and Environmental Engineering Center for Sustainable Development & Global Competitiveness Codiga Resource Recovery Center Stanford University Stanford CA 94305-4020 USA Department of Biochemistry and Microbiology Institute of Chemical Technology Prague Technicka 3 166 28 Prague Czech Republic Environmental Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831 USA Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA Department of Crop and Soil Sciences Texas A&M University College Station TX 77843 USA

Stable isotope probing （SIP） was used to identify microbes stimulated by ethanol addition in microcosms containing two sediments collected from the bioremediation test zone at the US Department of Energy Oak Ridge site, TN, USA. One sample was highly bioreduced with ethanol while another was less reduced. Microcosms with the respective sediments were amended with ^13C labeled ethanol and incubated for 7 days for SIP. Ethanol was rapidly converted to acetate within 24h accompanied with the reduction of nitrate and sulfate. The accumulation of acetate persisted beyond the 7 d period. Aqueous U did not decline in the microcosm with the reduced sediment due to desorption of U but continuously declined in the less reduced sample. Microbial growth and concomitant 13C-DNA production was detected when ethanol was exhausted and abundant acetate had accumulated in both microcosms. This coincided with U（VI） reduction in the less reduced sample. I3C originating from ethanol was ultimately utilized for growth, either directly or indirectly, by the dominant microbial community members within 7 days of incubation. The microbial community was comprised predominantly of known denitrifiers, sulfate-reducing bacteria and iron （Ⅲ） reducing bacteria including Desulfovibrio, Sphingomonas, Ferribacterium, Rhodanobacter, Geothrix, Thiobacillus and others, including the known U（VI）-redueing bacteria Acidovorax, Anaeromyxobacter, Desulfovibrio, Geobac- ter and Desulfosporosinus. The findings suggest that ethanol biostimulates the U（VI）-reducing microbial com- munity by first serving as an electron donor for nitrate, sulfate, iron （IH） and U（VI） reduction, and acetate which then functions as electron donor for U（VI） reduction and carbon source for microbial growth.

关键词： Stable isotope probing （S/P） ethanol acetate uranium reduction sediment bioremediation

Molecular dynamics of oxynitride glasses

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Molecular dynamics of oxynitride glasses

The Modeling of Production and Economic Indicators in Suckler Cows Herds

2005年国际玻璃讨论会暨国际玻璃协会年会

作者： Jan Machaceka ondrej Gedeona Marek Liskab Department of Glass and Ceramics Institute of Chemical Technology Technicka 5 CZ-166 28 Prague Czech Republic. Department of Glass and Ceramics Institute of Chemical Technology Technicka 5 CZ-166 28 Prague Czech Republic. Vitrum Laugaricio - Joint Glass Center of Institute of Inorganic Chemistry SAS Alexander Dubcek University of Trencin and RONA Lednicke Rovne Studentska 2 SK-911 50 Trencin Slovak Republic

Empirical parameterization of pair-interatomic potentials for oxynitride glasses was developed by means of ab-initio calculations. The potentials were applied in classical molecular dynamics simulatio

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Journal of Agricultural Science and Technology(A) 2014年第1期4卷 93-101页

作者： Andrej Koleno Jan fluba Zuzana Krupova Monika Michalickova ondrej Debreceni Department of Quality Control and Quality Management RAJO a.s. Studen6 35 Bratislava 823 55 Slovak Republic Institute of Animal Breeding and Product Quality Animal Production Research Centre Nitra Hlohoveck~ 2 Lu2ianky 951 41Slovak Republic Department of Genetics and Breeding of Farm Animals Institute of Animal Science Praha Uhrineves Pratelstvi 815 104 00Czech Republic Faculty of Agrobiology and Food Resources Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 949 76 SlovakRepublic

The aim of this study was to analyse the most important factors affecting the profitability of suckler cows herds in Slovakia in 2010. The economic models were used to verify whether the suckler cows farming is profitable without subsidies in the current production conditions in Slovakia as well as their optimal location in the agricultural natural conditions of Slovakia from the perspective of economic efficiency. The breeding of cattle, mainly for the beef meat production, has long been unprofitable as it is apparent also from the analysis of several studies. In the model without inclusion of subsidies, it was calculated that the suckler cows farming is unprofitable at the current production parameters and realization prices of calves. The losses per cow and year were ranged from -240 in the model by using a combination of the maximum threshold values of input parameters to -818 by using a combination of the minimum threshold values of the input parameters. In the models including of subsidies amount of loss and/or profit per cow and year varied depending on the input parameters mainly on natality, average daily gain, the realization price of calves and the level of subsidies provided to breeder as well. The economic results are ranged from -277 to 724 per cow and year. From economical as well as production point of view, the most appropriate agricultural natural regions for suckler cows farming in Slovakia are upland and highland regions.

关键词：奶牛养殖经济指标生产条件哺乳斯洛伐克建模经济模型输入参数

Multi-octave-spanning supercontinuum generation through high-energy laser filaments in YAG and ZnSe pumped by a 2.4 μm femtosecond Cr:ZnSe laser

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High Power Laser Science and Engineering 2021年第1期9卷 109-117页

作者： Sang-Hoon Nam Garima CNagar Dennis Dempsey ondrej Novák Bonggu Shim Kyung-Han Hong Research Laboratory of Electronics Massachusetts Institute of Technology(MIT)CambridgeMA 02139USA Department of Physics Applied Physics and AstronomyBinghamton UniversityState University of New YorkBinghamtonNY 13902USA HiLASE Centre Institute of Physics of the Czech Academy of Sciences25241 DolníBrežanyCzech Republic Presently with MIT Lincoln Laboratory LexingtonMA 02420USA

We present experimental and numerical investigations of high-energy mid-infrared filamentation with multi-octavespanning supercontinuum generation(SCG), pumped by a 2.4 μm, 250 fs Cr:ZnSe chirped-pulse laser amplifier.The SCG is demonstrated in both anomalous and normal dispersion regimes with YAG and polycrystalline ZnSe,respectively. The formation of stable and robust single filaments along with the visible-to-mid-infrared SCG is obtained with a pump energy of up to 100 μJ in a 6-mm-long YAG medium. To the best of the authors’ knowledge, this is the highest-energy multi-octave-spanning SCG from a laser filament in a solid. On the other hand, the SCG and evenharmonic generation based on random quasi-phase matching(RQPM) are simultaneously observed from the single filaments in a 6-mm-long polycrystalline ZnSe medium with a pump energy of up to 15 μJ. The numerical simulations based on unidirectional pulse propagation equation and RQPM show excellent agreement with the measured multioctave-spanning SCG and even-harmonic generation. They also reveal the temporal structure of mid-infrared filaments,such as soliton-like self-compression in YAG and pulse broadening in ZnSe.

关键词： laser filamentation mid-infrared laser nonlinear optics ultrafast optics

Hepatic phenotypes of HNF1B gene mutations:A case of neonatal cholestasis requiring portoenterostomy and literature review

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World Journal of Gastroenterology 2015年第8期21卷 2550-2557页

作者： Radana Kotalova Petra Dusatkova ondrej Cinek Lenka Dusatkova Tomas Dedic Tomas Seeman Jan Lebl Stepanka Pruhova Department of Pediatrics 2nd Faculty of Medicine Charles University in Prague and University Hospital Motol

Hepatocyte nuclear factor 1-β(HNF1B)defects cause renal cysts and diabetes syndrome(RCAD),or HNF1B-maturity-onset diabetes of the young.However,the hepatic phenotype of HNF1B variants is not well studied.We present a female neonate born small for her gestational age[birth weight 2360 g;-2.02standard deviations(SD)and birth length 45 cm;-2.40 SD at the 38th gestational week].She developed neonatal cholestasis due to biliary atresia and required surgical intervention(portoenterostomy)when 32-d old.Following the operation,icterus resolved,but laboratory signs of liver dysfunction persisted.She had hyperechogenic kidneys prenatally with bilateral renal cysts and pancreatic hypoplasia postnatally that led to the diagnosis of an HNF1B deletion.This represents the most severe hepatic phenotype of an HNF1B variant recognized thus far.A review of 12 published cases with hepatic phenotypes of HNF1B defects allowed us to distinguish three severity levels,ranging from neonatal cholestasis through adult-onset cholestasis to noncholestatic liver impairment,all of these are associated with congenital renal cysts and mostly with diabetes later in life.We conclude that to detect HNF1B variants,neonates with cholestasis should be checked for the presence of renal cysts,with special focus on those who are born small for their gestational age.Additionally,patients with diabetes and renal cysts at any age who develop cholestasis and/or exocrine pancreatic insufficiency should be tested for HNF1B variants as the true etiological factor of all disease components.Further observations are needed to confirm the potential reversibility of cholestasis in infancy in HNF1B mutation/deletion carriers.

关键词： Hepatocyte nuclear factor 1-β Renal cysts and diab

Colorectal cancer screening:20 years of development and recent progress

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World Journal of Gastroenterology 2014年第14期20卷 3825-3834页

作者： Miroslav Zavoral Stepan Suchanek ondrej Majek Premysl Fric Petra Minarikova Marek Minarik Bohumil Seifert Ladislav Dusek Department of Medicine 1st Faculty of MedicineMilitary University HospitalCharles University Institute of Biostatistics and Analyses Masaryk University Genomac Research Institute Centre for Applied Genomics of Solid Tumors Institute of General Medicine 1st Faculty of MedicineCharles University

Colorectal cancer(CRC)is the second most common cancer in Europe and its incidence is steadily increasing.This trend could be reversed through timely secondary prevention(screening).In the last twenty years,CRC screening programs across Europe have experienced considerable improvements(fecal occult blood testing;transition from opportunistic to population based program settings).The Czech Republic is a typical example of a country with a long history of nationwide CRC screening programs in the face of very high CRC incidence and mortality rates.Each year,approximately 8000 people are diagnosed with CRC and some 4000 die from this malignancy.Twenty years ago,the first pilot studies on CRC screening led to the introduction of the opportunistic Czech National Colorectal Cancer Screening Program in 2000.Originally,this program was based on the guaiac fecal occult blood test(FOBT)offered by general practitioners,followed by colonoscopy in cases of FOBT positivity.The program has continuously evolved,namely with the implementation of immunochemical FOBTs and screening colonoscopy,as well as the involvement of gynecologists.Since the establishment of the Czech CRC Screening Registry in 2006,2405850 FOBTs have been performed and 104565 preventive colonoscopies recorded within the screening program.The overall program expanded to cover 25.0%of the target population by 2011.However,stagnation in the annual number of performed FOBTs lately has led to switching to the option of a population-based program with personal invitation,which is currently being prepared.

关键词： Colorectal cancer Population-based screening progr