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In vivo and in vitro study of resorbable magnesium wires for medical implants:mg purity,surface quality,Zn alloying and polymer coating

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Journal of magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.Luňácková m.Jex m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištejnová J.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Department of materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Department of Composites and Carbon materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

magnesium is an excellent material in terms of biocompatibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation limit the potential of mg-based *** low-alloyed mg-Zn wires can strongly reduce problems with large H_(2)bubbles and improve the mechanical properties considerably while maintaining excellent long-term *** pickling and a polymer coating can be effectively used to lower the rate of in vivo *** this work,microstructural,mechanical,and in vitro characterization of 250μm and 300μm extruded wires made from ultra-pure mg,commercially pure mg,mg-0.15Zn,mg-0.4Zn and mg-1Zn was ***,mg-0.4Zn wires together with a variant coated with a copolymer of L-lactide andε-caprolactone were tested in vivo on artificially damaged Wistar rat *** on the observed mg-induced osteogenesis,polymer-coated mg wires with a small addition of Zn are a perspective material for bone-support applications,such as cerclage and fixation wires.

关键词： magnesium Resorbable mg wire mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation

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Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期 139-150页

作者： m.Füle A.P.kovács T.Gilinger m.Karnok P.Gaál S.Figul G.marowsky K.Osvay National Laser-Initiated Transmutation Laboratory University of Szeged Department of Experimental Physics University of Szeged ELI ALPS ELI-HU Non-Profit Ltd. Department of Optics and Quantum Electronics University of Szeged Advanced microfluidic Systems GmbH

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10, 11 and 18 μm in diameter. The sheet's position stability was found to be better than a few micrometers. Upon interaction with 50 mJ laser pulses, the 18 μm jet has a resonance amplitude of 16 μm at a repetition rate of 33 Hz, while towards 100 Hz it converges to 10 μm for all nozzles. A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum, with a measurement range of 182 nm±1 μm and an accuracy of±3%. The overall shape and 3D shape of the sheet follow the Hasson±Peck model in air. In vacuum versus air, the sheet gradually loses 10% of its thickness, so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

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Factors Influencing the Acidification Trends in Agriculture Soils: A Case Study of Slovakia

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Journal of Geoscience and Environment Protection 2024年第9期12卷 269-282页

作者： Jarmila makovníková Stanislav Kološta Boris Pálka National Agricultural and Food Centre/Soil Science and Conservation Research Institute Bratislava Regional Station Banská Bystica Slovakia Faculty of Ecomonics Matej Bel University in Banská Bystrica Tajovského Banská Bystrica Slovakia

This study aims to evaluate the development of soil reaction values in 15 key localities of soil Partial monitoring System from 1994 to 2023, and to identify the most important regional drivers of pH value development. Soil samples were collected from the depth 0 - 0.10 m yearly in the spring (5 samples from each locality). In the dry soil, samples were determined actively and exchanged soil reaction. The most significant negative changes (decreases of soil reaction) were determined in Haplic Stagnosols group and Cambisols group. The pH value in topsoil is primarily controlled by soil type and soil substrate, soil management and land use, and to a lesser extent by climatic region.

关键词： pH Value Acidification Climatic Region Soil Type

肾脏叶酸受体1基因变异导致自发性高血压大鼠发生代谢综合征

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中华高血压杂志 2015年第11期23卷 1099-1099页

作者： Pravenec m Kozich V Krijt J Sokolová J Zídek V Landa V mlejnek P ilhavy J imáková m kop V Trnovská J Kazdová L Kajiya T Wang J Kurtz TW 赵狄练桂丽

同型半胱氨酸以及其他含硫氨基酸代谢与叶酸代谢密切相关。该研究在自发性高血压大鼠（spontaneously hypertensiverats，SHR）与棕色挪威大鼠的重组近交系BXH／HXB中分析叶酸及含硫氨基酸在代谢综合征发展中的可能作用。方法：在含有... 详细信息

同型半胱氨酸以及其他含硫氨基酸代谢与叶酸代谢密切相关。该研究在自发性高血压大鼠（spontaneously hypertensiverats，SHR）与棕色挪威大鼠的重组近交系BXH／HXB中分析叶酸及含硫氨基酸在代谢综合征发展中的可能作用。方法：在含有调节肾脏叶酸受体1mRNA水平的顺式作用表达数量性状基因座的1号染色体区绘制半胱氨酸浓度的数量性状基因座。

关键词：自发性高血压大鼠代谢综合征叶酸代谢受体1 基因变异肾脏数量性状基因座同型半胱氨酸

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Enabling Technologies for Autonomous Robotic Systems in manufacturing

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 403-431页

作者： ERDŐS Gábor ABAI Kristóf BEREGI Richárd CSEmPESZ János CSERTEG Tamás GODÓGábor HAJÓS mátyás HÁY Borbála HORVÁTH Dániel HORVÁTH Gergely JUNIKIÁdám KEmÉNY Zsolt kovÁCS András NACSA János PANITI imre PEDONE Gianfranco TAKÁCS Emma TIPARY Bence ZAHORÁN László VÁNCZA József Institute for Computer Science and Control Hungarian Research Network(HUN-REN SZTAKI)BudapestHungary Department of manufacturing Science and Technology Budapest University of Technology and Economics(BME)BudapestHungary EPIC InnoLabs Nonprofit Ltd. BudapestHungary Eötvös Loránd University(ELTE) BudapestHungary

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the *** operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication *** enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by *** paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such *** case studies will be presented from recent practice at HUN-REN SZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and *** various solutions have in common that they use a generic digital twin concept as their *** making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

关键词： industrial robotics autonomy digital twin enabling technology

Laser-driven electrodynamic implosion of fast ions in a thin shell

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matter and Radiation at Extremes 2023年第5期8卷 73-81页

作者： S.Yu.Gus’kov Ph.Korneev m.murakami P.N.Lebedev Physical Institute of Russian Academy of Sciences 53 Leninskii Prospect119991 MoscowRussian Federation Institute of Laser Engineering Osaka University565-0871 OsakaJapan

Collision of laser-driven subrelativistic high-density ion flows provides a way to create extremely compressed ion conglomerates and study their *** paper presents a theoretical study of the electrodynamic implosion of ions inside a hollow spherical or cylindrical shell irradiated by femtosecond petawatt laser *** propose to apply a very effective mechanism for ion acceleration in a self-consistent field with strong charge separation,based on the oscillation of laser-accelerated fast electrons in this field near the thin *** electrons are generated on the outer side of the shell under irradiation by the intense laser *** is shown that ions,in particular protons,may be accelerated at the implosion stage to energies of tens and hundreds of meV when a sub-micrometer shell is irradiated by femtosecond laser pulses with an intensity of 10^(21)–10^(23)W cm^(−2).

关键词： dynamic thin irradiated

Species traits and shoot-root biomass allocation in 20 dry-grassland species

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Journal of Plant Ecology 2018年第2期11卷 273-285页

作者： Iveta Husáková Jacob Weiner Zuzana münzbergová Department of Botany Faculty of ScienceCharles UniversityBenátská2CZ-12801 PragueCzech Republic Institute of Botany Academy of Sciences of the Czech RepublicZámek 1CZ-25243 PrůhoniceCzech Republic Department of Plant and Environmental Sciences University of CopenhagenThorvaldsensvej 40DK-1871 FrederiksbergDenmark

Aims A plant has a limited amount of resources at any time and it allo-cates them to different *** spite of the large number of previous studies on allocation patterns within single species,knowledge of general patterns in species allocation is still very *** is because each study was done in different condi-tions using different methodology,making generalization *** investigate intraspecific above-versus below-ground biomass allocation among individuals across a spectrum of dry-grassland plant species at two different developmental stages and ask whether allocation is age-and species specific,and whether differences among species can be explained by their life-history traits and *** We collected data on above-and below-ground biomass of seedlings and adult plants of 20 species from a common garden *** analysed data on shoot-root biomass allocation allometrically and studied the relationship between the allometric exponents(slopes on log-log scale),species life-history traits and phylogenetic *** Findings We found isometric as well as allometric patterns of biomass alloca-tion in the studied *** and adult individuals of more than half of the species differed in their above-versus below-ground biomass allometric *** and adult individuals of the remaining species differed in their allometric coefficients(inter-cepts).Annual species generally allocated proportionally more to above-than below-ground biomass as seedlings than as adults,whereas perennial species showed the opposite *** life-history traits,such as plant life span,age of first flowering,month in which the species begin flowering and specific leaf area were much more important in explaining differences in shoot-root allometry among species than were phylogenetic *** suggests that allocation patterns vary greatly among closely related species but can be predicted based on species life-hi

关键词： above-ground biomass below-ground biomass allometry isometry seedling adult plant life-history traits phylogenetic relatedness root-shoot ratio

Rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： mria GEROV,Jozef TRK,Ol’ga PECHV,Jana mATUkov Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology medical School Comenius University Bratislava Slovak Republic Now in Center for Blood Research and Department of Pathology Harvard medicalSchool Boston USA.

Aim: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. mETHODS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAmE) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilmenidine administered simultaneously with L-NAmE (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity

Biodegradable zinc-iron alloys: Complex study of corrosion behavior,mechanical properties and hemocompatibility

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Progress in Natural Science:materials International 2021年第2期31卷 279-287页

作者： Z.Orságová Králová R.Gorejová R.Orin?aková m.Petra?ková A.Orin?ak m.Kupková m.Hrubov?a?ková T.Sop?ák m.Baláz? I.maska?ová A.kovalc?íková K.kova? Department of Physical Chemistry Faculty of Science Pavol Jozef ?afa?rik University in Ko?ice Institute of materials Research Slovak Academy of Sciences Institute of Geotechnics Slovak Academy of Sciences University of Veterinary medicine and Pharmacy in Ko?ice Department of Animal Nutrition Dietetics and Animal Breeding

Zn-Fe alloys have been extensively investigated in this study with a view to their application as biodegradable bone implants. Biogenic element zinc is a very appropriate metal because of the ideal degradation rate compared to those of mg and Fe. Studied alloys were made by compressing metallic powders in a content ratio of 100% Zn,Zn-1% Fe, Zn-2% Fe, Zn-5% Fe and Zn-10% Fe and sintering at 350°C for 1 h. Prepared samples were examined by optical microscopy, SEm and XRD. Corrosion behavior, mechanical testing and hemocompatibility were observed subsequently. The electrochemical performance of such materials was studied in the simulated body fluids. The enhanced corrosion rate was observed for all samples after iron addition due to the micro-galvanic effect between the pure Zn and Zn;Fe intermetallic phase. The corrosion rate of the Zn-5% Fe alloyed sample was more than 20-times higher（2.89 mmpy） compared to the pure Zn. However, alloying with more than 5 wt %of iron diminished the mechanical performance of the material. Therefore, the performed mechanical and hemocompatibility tests showed acceptable biocompatibility of zinc and Zn-1% Fe and Zn-2% Fe samples.

关键词： Biodegradable materials Zinc Iron Alloy Corrosion behavior Hemocompatibility