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Manipulation of spermatogonial stem cells in livestock species

Journal of Animal Science and Biotechnology 2019年第4期10卷 833-850页

作者： Filipp Savvulidi Martin Ptacek Karina Savvulidi Vargova ludek stadnik Department of Animal Science Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PragueKamycká12916500 PragueSuchdolCzech Republic Institute of Pathological Physiology First Faculty of MedicineCharles University in PragueU Nemocnice 512853 PragueCzech Republic

We are entering an exciting epoch in livestock biotechnology during which the fundamental approaches(such as transgenesis, spermatozoa cryopreservation and artificial insemination) will be enhanced based on the modern understanding of the biology of spermatogonial stem cells(SSCs) combined with the outstanding recent advances in genomic editing technologies and in vitro cell culture systems. The general aim of this review is to outline comprehensively the promising applications of SSC manipulation that could in the nearest future find practical application in livestock breeding. Here, we will focus on 1) the basics of mammalian SSC biology;2) the approaches for SSC isolation and purification;3) the available in vitro systems for the stable expansion of isolated SSCs;4) a discussion of how the manipulation of SSCs can accelerate livestock transgenesis;5) a thorough overview of the techniques of SSC transplantation in livestock species(including the preparation of recipients for SSC transplantation,the ultrasonographic-guided SSC transplantation technique in large farm animals, and the perspectives to improve further the SSC transplantation efficiency), and finally, 6) why SSC transplantation is valuable to extend the techniques of spermatozoa cryopreservation and/or artificial insemination. For situations where no reliable data have yet been obtained for a particular livestock species, we will rely on the data obtained from studies conducted in rodents because the knowledge gained from rodent research is translatable to livestock species to a great extent. On the other hand, we will draw special attention to situations where such translation is not possible.

关键词： CRISPR/Cas9 Genome editing Livestock transgenesis Long-term culture systems Male germline stem cells,Recipient preparation Sertoli cells Spermatogonial stem cells Ultrasonographic-guided cannulation

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Ion emission from warm dense matter produced by irradiation with a soft x-ray free-electron laser

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Matter and Radiation at Extremes 2024年第1期9卷 71-84页

作者： Josef Krása Tomás Burian Vera Hájková Jaromír Chalupský Šimon Jelínek Katerina Frantálová Michal Krupka Zuzana Kuglerová Sushil Kumar Singh Vojtech Vozda ludek Vysín MichalŠmíd Pablo Perez-Martin Marion Kühlman Juan Pintor Jakub Cikhardt Matthias Dreimann Dennis Eckermann Felix Rosenthal Sam M.Vinko Alessandro Forte Thomas Gawne Thomas Campbell Shenyuan Ren YuanFeng Shi Trevor Hutchinson Oliver Humphries Thomas Preston Mikako Makita Motoaki Nakatsutsumi Xiayun Pan Alexander Köhler Marion Harmand Sven Toleikis Katerina Falk Libor Juha Department of Radiation and Chemical Physics Institute of PhysicsCzech Academy of SciencesNa Slovance 218221 Prague 8Czech Republic Laser Plasma Department Institute of Plasma PhysicsCzech Academy of SciencesZa Slovankou 318200 Prague 8Czech Republic Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles University in PragueV Holesovi ckách 218000 Prague 8Czech Republic Department of Physical Electronics Faculty of Nuclear Science and Engineering PhysicsCzech Technical University in PragueV Holesovi ckách 218000 Prague 8Czech Republic Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstraße 40001328 DresdenGermany DESY Photon Science Notkestraße 85D-22607 HamburgGermany Institut de Minéralogie de Physique des Matériaux et de CosmochimieUMR 7590–UPMC/CNRS/IRD/MNHNSorbonne Université4 place Jussieu75005 ParisFrance Department of Physics Faculty of Electrical EngineeringCzech Technical University in PragueTechnická216627 Prague 6Czech Republic Center for Soft Nanoscience University of MünsterBusso-Peus-Straße 10D-48149 MünsterGermany Department of Physics Clarendon LaboratoryUniversity of OxfordParks RoadOxford OX13PUUnited Kingdom Central Laser Facility STFC Rutherford Appleton LaboratoryDidcot OX110QXUnited Kingdom Lawrence Livermore National Laboratory 7000 East AvenueLivermoreCalifornia 94550USA European XFEL GmbH Holzkoppel 4D-22869 SchenefeldGermany Technische Universität Dresden 01062 DresdenGermany

We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric *** the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted Maxwell–Boltzmann velocity distribution *** find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped *** morphology of the complex crater structure indicates the presence of several ion groups with varying *** find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.

关键词： electrostatic emitted chemi

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Electro-Oxidation of Concentrated Ce(Ⅲ) at Carbon Felt Anode in Nitric Acid Media

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Journal of Rare Earths 2006年第3期24卷 257-263页

作者： Jelinek ludek Mikio Kumagai Nuclear Chemistry and Chemical Engineering Center Institute of Research and Innovation 1201 Takada Kashiwa 277-0861 Chiba-ken Japan

Electro-oxidation of Ce （ Ⅲ ） to Ce （ Ⅳ ） in parallel plate flow type electrolyzer divided with cation exchange membrane was carried out in nitric acid media at carbon felt anode under galvanostatic conditions. Carbon felt was used as an anode for its high specific surface area and high oxygen evolution overpotential. Pt coated Ti plates were used as cathode and anode current feeder. The oxidation of 1 mol· L^-1 Ce（ Ⅲ ） solution in 2 mol· L^- 1 HNO3 was proceeding with a high current efficiency （92%） until about 80% of Ce（ Ⅲ ） was oxidized. Then, oxygen evolution, accompanied by terminal voltage jump, took place, lowering current efficiency. Ce（ Ⅲ ） was oxidized up to 90% with current efficiency of 62%. In this mode, strong carbon felt anode oxidation was observed. The wear out of carbon felt was 46% in six consequent runs （6 h of operation）. After each run, carbon felt surface had to be renewed with slightly alkaline solution to remove carbon oxidation products and ensure regular operational conditions. When anode surface was blocked, oxygen evolution took place from the beginning of electrolysis due to higher actual current density. The wear out of carbon felt anode could be minimized by means of oxygen evolution prevention. In the case when electrolysis had been stopped before oxygen evolution started （at Ce（ Ⅳ ） conversion of about 80% ）, the wear out of anode was less than 2% during 6 consequent runs （4 h of operation）.

关键词： electrolyzer Ce oxidation carbon felt anode rare earths

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Adsorption of Ce(Ⅳ) Anionic Nitrato Complexes onto Anion Exchangers and Its Application for Ce(Ⅳ) Separation from Rare Earths(Ⅲ)

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Journal of Rare Earths 2006年第4期24卷 385-391页

作者： ludek Jelinek Mikio Kumagai Nuclear Chemistry and Chemical Engineering Center Institute of Research and Innovation1201 Takada Kashiwa 277-0861 Chiba-prefecture Japan

Ce （Ⅳ） nitrato complexes were adsorbed on two anion exchangers based on polyvinyl pyridine （PVP） and quatemized PVP incorporated into porous silica matrix. The effect of nitric acid concentration （0.5～6 mol·L^-1） and temperature （278 ～318 K） on Ce（ Ⅳ ） sorption efficiency was investigated. Sorption increased with increasing nitric acid concentration, indicating that [Ce（NO3）6]^2- complex is the main adsorbed Ce（Ⅳ） species. Oxidation of sorbents by adsorbed Ce （ Ⅳ ） species resulting in Ce （ Ⅲ ） release to the solution was observed. Pyridine based anion exchangers exhibited higher oxidation stability compared to the commercial strong base anion exchanger. Ce（ Ⅳ ） reduction was temperature dependent and obeyed pseudo-first-order reaction kinetics. Column separation of Ce （ Ⅳ ） from La （ Ⅲ ） and Y （ Ⅲ ） was carried out from 6 mol·L^-1 nitric acid with PVP based anion exchanger. Reasonable Ce （Ⅳ） breakthrough capacity （0.7 mol·kg^-1 PVP） was achieved. No remarkable decrease of capacity was observed within 3 consequent runs. In contrast, Ce （Ⅲ） leakage due to reduction decreased and breakthrough capacity slightly increased. This effect was more pronounced with increasing temperature. Regeneration with 0.1 mol·L^- 1 nitric acid was successful （recovery 100% ± 4% ） and Ce solution of high purity （〉 99.97% ） with respect to La and Y content was gained.

关键词： ion exchange tetravalent cerium separation rare earths

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Modeling of IPMC Cantilever＇s Displacements and Blocking Forces

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Journal of Bionic Engineering 2015年第1期12卷 142-151页

作者： David Vokoun Qingsong He ludek Heller Min Yu Zhendong Dai Institute of Physics of the ASCR Prague 182 21 Czech Republic Institute of Bio-lnspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The motion of an Ionic Polymer Metal Composite （IPMC） cantilever under a periodic voltage control is modeled. In our finite element 3D model, we follow both the free tip displacements and the blocking forces for various thicknesses and elastic constants of the ionomer membrane. It turns out that the maximum displacement of the free tip strongly depends on the value of the Young＇s modulus of the electrodes. Furthermore, the maximum blocking force, Fmax, increases with the thickness of the ionomer membrane. At constant values of Young＇s moduli of the electrodes and ionomer membrane thickness, if the Young＇s modulus of the ionomer membrane varies within the range from 0.2 MPa to 1 GPa, the change of Fmax is less than 10 %. The simulated maximal displacements, blocking forces and electrical currents are compared with the corresponding sets of ex- perimental data, respectively. Qualitative agreement between the simulated and the respective measured data profiles is ob- tained. Furthermore, it is found that the assumption of electrostatic interactions in the cation depleted region of the ionomer membrane has a negligible effect. The advantage of the model consists in its simplicity.

关键词： ionic polymer metal composite actuator blocking force finite element method

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Association between Childhood Leukaemia and Exposure to Power-frequency Magnetic Fields in Middle Europe

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Biomedical and Environmental Sciences 2012年第5期25卷 597-601页

作者： Vitezslav JIRIK ludek PEKAREK Vladimir JANOUT Hana TOMASKOVA Department of Epidemiology and Public Health Faculty of Medicine University of Ostrava Department of Biophysics Faculty of Science Palacky University Olomouc National Institute of Public Health

Abstract Objective Higher levels of exposure to extremely low-frequency magnetic fields （ELF-MF） are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF-MF exposure and childhood leukaemia in the Czech Republic. Methods We conducted a paired case-control study. The cases （children with leukaemia） were age- sex- and permanent residence-matched to controls （children without leukaemia）. Although this limited potential bias and confounding, it also limited our number of participants. Results The matched analyses included 79 case-control pairs. No significant association between ELF-MF exposure and childhood leukaemia was observed for exposures over 0.2 μT （odds ratio [0R]=0.93, confidence interval [Cl]=0.45-1.93）, 0.3 μT （0R=0.77, Cl=0.34-1.75）, or 0.4 μT （OR=0.9, Cl=0.37-2.22）. Conclusion Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF-MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries.

关键词： Childhood leukaemia Power-frequency magnetic field exposure Extremely low-frequencymagnetic field Housing types

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Problem of the reference height of the projectile trajectory as a reduced meteo-ballistic weighting factor

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Defence Technology（防务技术） 2014年第2期10卷 131-140页

作者： Vladimir CECH ludek JEDLICKA Jiri JEVICKY Oprox Inc.Kulkova 8 Department of Weapons and Ammunition University of DefenceKounicova 65 Department of Mathematics and Physics University of DefenceKounicova 65

This paper deals with the issue of preparation of the aiming angles with the use of tabular firing tables and needed determination of the ballistic elements μ_B(ballistic wind w_B,w_(xB),w_(ZB),ballistic(virtual) temperature τ_*** density p_B) from the standardized met *** weighting factors are used for the calculation of ballistic elements μ_B that are incorporated into the trajectory calculations characteristics of weapon and *** different methodologies practically used in the praxis are analysed and *** the comparison of the two methodologies the reference height of trajectory determined from the weighting factor functions is *** the basis of the analyses conducted,the potential for further increase in accuracy of these aiming angles preparation methods is pointed out.

关键词：加权因子弹道风基准气象弹丸制备方法瞄准角道密度

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Direct Spectroscopic Determination of Europium（ Ⅱ ） Concentration During Europium（ Ⅲ ） Electro-Reduction in Hydrochloric Acid Medium

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Journal of Rare Earths 2007年第1期25卷 1-5页

作者： ludek Jelinek Tsuyoshi Arai Wei Yuezhou Mikio Kumagai Institute of Research and Innovation （IRI） 1201 Takada Kashiwa 277-0861 Japan

UV-Vis spectroscopy was used to directly determine the concentration of Eu（ Ⅱ） during electroreduction of Eu （ Ⅲ ） in hydrochloric acid medium. Electroreduction was carried out in a flow type electrolyzer with glassy carbon cathode at the constant potential of - 800 mV vs. Ag/AgCl. The effects of oxygen and concentration of hydrochloric acid on the system were investigated. For 0.01 mol· L^-1 hydrochloric acid, calibration curves for Eu （Ⅱ） absorption bands at 248 and 320 nm were constructed. Molar absorption coefficients were estimated to be 2016 and 648 L· mol^-1·cm^-1, respectively. The absorbance strongly decreased with decrease in pH of the solution, whereas concentration of chloride had only a negligible effect.

关键词： Eu( Ⅱ ) electroreduction hydrochloric acid UV spectroscopy rare earths

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Zinc phosphate-based nanoparticles as alternatives to zinc oxide in diet of weaned piglets

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Journal of Animal Science and Biotechnology 2020年第4期11卷 1147-1162页

作者： Silvia Kociova Kristyna Dolezelikova Pavel Horky Sylvie Skalickova Daria Baholet Lucie Bozdechova Eva Vaclavkova Jaroslava Belkova Pavel Nevrkla Jiri Skladanka Tomas Do Ondrej Zitka Yazan Haddad Pavel Kopel ludek Zurek Vojtech Adam Kristyna Smerkova Department of Chemistry and Biochemistry Mendel University in BrnoZemedelska 1CZ-61300 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 123CZ-61200 BrnoCzech Republic Department of Animal Nutrition and Forage Production Mendel University in BrnoZemedelska 1CZ-61300 BrnoCzech Republic Institute of Animal Science Pratelstvi 815CZ-10400 Praha UhrinevesCzech Republic Department of Animal Breeding Mendel University in BrnoZemedelska 1CZ-61300 BrnoCzech Republic Department of Inorganic Chemistry Faculty of SciencePalacky University17.listopadu 12CZ-77146 OlomoucCzech Republic Central European Institute of Technology Center for ZoonosesUniversity of Veterinary and Pharmaceutical SciencesBrnoPalackeho 1946/1CZ-61242 BrnoCzech Republic.

Background: The high doses of zinc oxide(Zn O) administered orally to piglets for the prevention of diarrhea and increase of growth rate can contaminate pig farms and the surrounding environment. Therefore, there is a need to find a replacement of high doses of dietary Zn O with an equally effective alternative. In the present study, the effect of two formulations of zinc phosphate-based nanoparticles(Zn A and Zn C NPs) on growth performance,intestinal microbiota, antioxidant status, and intestinal and liver morphology was evaluated. A total of 100 weaned piglets were randomly divided into 10 equal groups with the base diet(control) or the base diet supplemented with Zn A, Zn C, or Zn O at concentrations 500, 1000, and 2000 mg Zn per kilogram of diet. Supplements were given to animals for 10 days. Fecal samples were collected on day 0, 5, 10 and 20. At the end of the treatment(day 10),three piglets from each group were sacrificed and ***: Comparing to that of control, the significantly higher piglet weight gain was observed in all piglet groups fed with Zn A(P < 0.05). Differences in the total aerobic bacteria and coliform counts in piglet feces after NPs supplementation compared to that of control and Zn O groups were also found(P < 0.05). The majority of aerobic culturable bacteria from the feces represented Escherichia(28.57–47.62%), Enterococcus(3.85–35.71%), and Streptococcus(3.70–42.31%) spp. A total of 542 Escherichia coli isolates were screened for the virulence genes STa,STb, Stx2, F4, and F18. The substantial occurrence of E. coli virulence factors was found on day 5, mainly in fimbrillary antigen and thermostable toxins, except for piglets fed by Zn C. Zn treatment decreased Zn blood levels in piglets fed with Zn O and Zn A(500 mg/kg) and increased in Zn C(2000 mg/kg) compared to that of control(P < 0.05). The antioxidant status of piglets was affected only by Zn A. While some changes in the liver and the intestinal morphology of piglets with

关键词： Antioxidant status Diet E.coli STa STb Stx2 F4 F18 Fecal coliforms Microbiota

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Meta-analysis on the role of testosterone and IGF-1 in the antler growth:New insight to old data

Meta-analysis on the role of testosterone and IGF-1 in the a...

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第二届中国鹿业发展大会

作者： ludek Bartos Erika Kuzmova George A.Bubenik Department of Ethology Institute of Animal SciencePragueCzech Republic Department of Ecology Charles UniversityPragueCzech Republic Department of Integrative Biology University of GuelphGuelphOntarioCanada

As an addition to half a century of discussions on hormonal control of antler growth,we have performed a meta-analysis of in vivo data on antler growth(from the start of antler re-growth after casting to the end of antler elongation) and their corresponding *** have evaluated 32 papers dealing with testosterone(T) concentrations in 10 deer *** studies varied in the number of subgroups(e.g.,

关键词： antler growth testosterone IGF-1 deer

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