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Hyperactive learning for data-driven interatomic potentials

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npj Computational materials 2023年第1期9卷 599-612页

作者： Cas van der Oord matthias Sachs Dávid Péter kovács Christoph Ortner Gábor Csányi University of Cambridge Cambridge CB21PZUK University of Birmingham Birmingham B152TTUK University of British Columbia VancouverBC V6T 1Z2Canada

Data-driven interatomic potentials have emerged as a powerful tool for approximating ab initio potential energy *** most time-consuming step in creating these interatomic potentials is typically the generation of a suitable training *** aid this process hyperactive learning(HAL),an accelerated active learning scheme,is presented as a method for rapid automated training database *** adds a biasing term to a physically motivated sampler(*** dynamics)driving atomic structures towards uncertainty in turn generating unseen or valuable training *** proposed HAL framework is used to develop atomic cluster expansion(ACE)interatomic potentials for the AlSi10 alloy and polyethylene glycol(PEG)polymer starting from roughly a dozen initial *** HAL generated ACE potentials are shown to be able to determine macroscopic properties,such as melting temperature and density,with close to experimental accuracy.

关键词： starting generating consuming

原位透射电镜研究双辊铸造AA8079铝合金的均匀化过程

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Transactions of Nonferrous metals Society of China 2022年第7期32卷 2138-2149页

作者： R.KRÁLÍK B.KŘIVSKÁ L.BAJTOŠOVÁ m.ŠLAPÁkovÁ m.CIESLAR Faculty of mathematics and Physics Charles UniversityKe Karlovu 312116 Prague 2Czechia

AA8079铝合金是一种常用的制造薄包装箔的胚料,其主要的合金化元素Fe和Si可以形成二元和三元金属间化合物。采用原位透射电镜模拟铸态材料均匀化退火,分析这些颗粒的形状、类型和分布的实时变化,它们影响最终产品的力学性能、材料对形... 详细信息

AA8079铝合金是一种常用的制造薄包装箔的胚料,其主要的合金化元素Fe和Si可以形成二元和三元金属间化合物。采用原位透射电镜模拟铸态材料均匀化退火,分析这些颗粒的形状、类型和分布的实时变化,它们影响最终产品的力学性能、材料对形成气孔和其他宏观缺陷的敏感性。对另一组铸态样品在模拟工业热处理制度范围内进行退火处理,并结合电阻率测量,验证原位试验的结果。结果表明,在450℃以上的原始颗粒球化、475℃的新颗粒成核、525℃以上的颗粒粗化以及550℃以上的原始颗粒完全溶解等几个阶段发生了回复、基体去饱和以及相变,且具有明显的温度区间。

关键词：铝合金原位退火均匀化箔胚料

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

Behaviour of cranes(family Gruidae)mirrors their phylogenetic relationships

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Avian Research 2021年第3期12卷 285-295页

作者： Nela Nováková Jan Robovský Faculty of Science University of South BohemiaBranišovská176037005ČeskéBudějoviceCzechia

Background:The behavioural repertoire of every species evolved over time and its evolution can be traced through the phylogenetic relationships in distinct ***(family Gruidae)represent a small,old,monophyletic group with well-corroborated phylogenetic relationships on the species level,and at the same time they exhibit a complex and well-described behavioural ***:We therefore investigated the evolution of behavioural traits of cranes in a phylogenetic context using several phylogenetic approaches and two types of trait *** cranes exhibit more than a hundred behavioural displays,almost one third of which may be phylogenetically ***:more than half of the analysed traits carry a significant phylogenetic *** ancestor of cranes already exhibited a quite complex behavioural repertoire,which remained unchanged in Balearicinae but altered greatly in Gruinae,specifically by the shedding of traits rather than their *** scoring has an influence on results within the Gruinae,primarily in genera Bugeranus and ***:Albeit the behavioural traits alone cannot be used for resolving species-level relationships within the Gruidae,when optimized on molecular tree,they can help us to detect interesting evolutionary transformations of behaviour repertoire within *** Limpkin(Aramus guarauna)seems to be the most enigmatic species and should be studied in detail for its behavioural repertoire,which may include some precursors of crane behavioural traits.

关键词： Ancestral behavioural repertoire Evolution Phylogenetic signal

A General Version of the Retract method for Discrete Equations

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Acta mathematica Sinica,English Series 2007年第2期23卷 341-348页

作者： Josef DIBLíK Irena RzIkov miroslava RZIkov Department of mathematics Faculty of Electrical Engineering and CommunicationBrno University of TechnologyTechnická 8616 00 BrnoCzech Republic Department of Applied mathematics Faculty of ScienceCilina UniversityHurbanova 15010 26 CilinaSlovak Republic

We study a problem concerning the compulsory behavior of the solutions of systems of discrete equations u（k ＋ 1） = F（k, u（k））, k ∈ N（a） = {a, a ＋ 1, a ＋ 2 }, a ∈ N,N= {0, 1,... } and F ： N（a） × R^n→R^n. A general principle for the existence of at least one solution with graph staying for every k ∈ N（a） in a previously prescribed domain is formulated. Such solutions are defined by means of the corresponding initial data and their existence is proved by means of retract type approach. For the development of this approach a notion of egress type points lying on the defined boundary of a given domain and with respect to the system considered is utilized. Unlike previous investigations, the boundary can contain points which are not points of egress type, too. Examples are inserted to illustrate the obtained result.

关键词： discrete equation consequent point retract

Human-altered soils–Signatures of Anthrosols and their potential for arable lands

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Soil Ecology Letters 2023年第3期5卷 109-121页

作者： michael O.Asare Wazi Apoh Jerry Owusu Afriyie Jiřina Száková Dinkayehu Alamnie Asrade Department of Agroenvironmental Chemistry and Plant Nutrition Faculty of Agrobiology Food and Natural ResourcesCzech University of Life SciencesKamýcká129CZ-16521 Prague 6Czech Republic Department of Archaeology and Heritage Studies University of GhanaP.O.Box L.G.3LegonGhana Department of Animal Science and Food Processing in the Tropics Faculty of Tropical AgriSciencesCzech University of Life SciencesPragueKamycka 129Prague 6–Suchdol CZ1651400Czech Republic

The fertility of human-altered soils,Anthrosols,developed from past settlement activities for crop production is scarcely *** study evaluated the fertility of Anthrosols developed from the 15th to mid-20th century AD settlement in Old Buipe,Savanna region,Ghana,to determine whether abandoned localities are suitable for arable *** activities enhanced the physical attributes of the Anthrosols:brown to dark brown intergrain fine soil,15%−35%organic matter,15%−30%potsherd,and 5%−15%charred *** Anthrosols were slightly acidic to neutral reactions(pH_([H_(2)O])5.67−6.83,pH_([cacl_(2)])5.83−6.95),high cation exchange capacity(CEC;18.77−45.31me/100 g),electric conductivity(EC=0.28−0.36 dS m^(−1)),accumulation,and distribution of organic C,total N,P,mn,Cu,Zn,K,and Fe,and available P,K,Ca,mg,S,mn,Fe,Cu,and ***-available nutrients were comparatively higher than concentrations in non-anthropogenic *** level of releasability(bioavailable fractions of total concentrations)of P,K,Ca,mn,Fe,Cu,and Zn partly compensates for low plant-available *** of chemical and physical properties of Anthrosols make them fertile for arable *** signatures of settlement activities are strong and can remain in soils for a long time,even under harsh environmental conditions.

关键词： arable field Anthrosols organic matter physical properties releasability settlement activities

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

Investigating adverse events in long-term care facilities:a systematized review

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Frontiers of Nursing 2023年第4期10卷 399-412页

作者： Dominika Kohanová martina Lepiešová Daniela Bartoníčková Pavol Faťun KatarínaŽiaková Department of Nursing Faculty of Social Sciences and Health CareConstantine the Philosopher University in NitraNitra 94901Slovak Republic Department of Nursing Jessenius Faculty of Medicine in MartinComenius University in BratislavaMartin 03601Slovak Republic Department of Nursing Faculty of Health SciencesPalackýUniversity in OlomoucOlomouc 77515Czech Republic

Objective:This systematized review aimed to synthesize the results of empirical studies focused on the types and factors of adverse events(AEs)that contribute to them in long-term care(LTC)***:The search was conducted in Pro Quest,Scopus,and Pub med in January 2021 and resulted in 1057 *** content analysis method was used in the data ***:In all,35 studies were identified as relevant for the *** analysis revealed 133 different types of AEs and 60 factors that contributed to ***:In LTC,various AEs occur,most of which are preventable,while many factors that influence their occurrence could be significantly *** an effective analysis of AEs in LTC,it is possible to minimize their occurrence and,at the same time,minimize their negative impact on all par ties concerned.

关键词： adverse event facility factors long-term care healthcare workers

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