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Reconstruction of the mid-Devonian HP-HT metamorphic event in the Bohemian massif(European Variscan belt)

Geoscience Frontiers 2022年第3期13卷 177-195页

作者： Stephen Collett Karel Schulmann Piérig Deiller PavlaŠtípská Vít Peresty marc Ulrich Yingde Jiang Luc de Hoÿm de marien jitka míková Centre for Lithospheric Research Czech Geological SurveyKlárov 311821 Praha 1Czech Republic Institut Terre et Environnement de Strasbourg UMR 7063 Universitéde Strasbourg—CNRS1 Rue Blessig67084 StrasbourgCedexFrance Institute of Petrology and Structural Geology Charles UniversityAlbertov 6Praha 212843Czech Republic State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Laboratories of the Czech Geological Survey Geologická615200 Praha 5Czech Republic

mid-Devonian high-pressure(HP)and high-temperature(HT)metamorphism represents an enigmatic early phase in the evolution of the Variscan *** the Bohemian massif this metamorphism is recorded mostly in allochthonous complexes with uncertain relationship to the major tectonic *** this regard,the mariánskéLázně Complex(mLC)is unique in its position at the base of its original upper plate(Teplá-Barrandian Zone).The mLC is composed of diverse,but predominantly mafic,magmatic-metamorphic rocks with late Ediacaran to mid-Devonian protolith ***-Devonian HP eclogite-facies metamorphism was swiftly followed by a HT granulite-facies overprint contemporaneous with the emplacement of magmatic rocks with apparent supra-subduction *** Hf in zircon isotopic measurements combined with a review of whole-rock isotopic and geochemical data reveals that the magmatic protoliths of the mLC,as well as in the upper plate Teplá-Barrandian Zone,developed above a relatively unaltered Neoproterozoic lithospheric *** remained coupled with this lithospheric mantle throughout a geological timeframe that encompasses separate Ediacaran and Cambrian age arc magmatism,protracted early Paleozoic rifting,and the earliest phases of the Variscan *** results are presented in the context of reconstructing the original architecture of the Variscan terranes up to and including the mid-Devonian HP-HT event.

关键词： Variscan Orogeny Avalonian-Cadomian Orogeny Eclogite Geochemistry Zircon Lu-Hf geochronology

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Anticlockwise metamorphic paths at ca.890–790 ma from the NE Baidrag block,mongolia,indicate back-arc compression at the Rodinia periphery

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Geoscience Frontiers 2023年第2期14卷 154-181页

作者： PavlaŠtípská Vít Peresty Igor Soejono Karel Schulmann RCAndrew Kylander-Clark Carmen Aguilar Stephen Collett martin Racek jitka míková Otgonbaatar Dorjsuren Nikol Novotná Czech Geological Survey 11821 Praha 1Czech Republic Institute of Petrology and Structural Geology Charles University in PragueAlbertov 6Praha 212800Czech Republic Institut Terre et Environnement de Strasbourg UMR 7063 Universitéde Strasbourg-CNRS1 Rue Blessig67084 StrasbourgCedexFrance Department of Earth Science University of CaliforniaSanta BarbaraCA 93106United States Department of mineralogy Petrology and Applied GeologyFaculty of Earth ScienceUniversity of Barcelona08028 BarcelonaSpain Institute of Geology Mongolian Academy of SciencesLabor Union StreetSonginokhairkhan DistrictUlaanbaatar 18080Mongolia

The processes leading to the assembly of the Rodinia supercontinent through Grenvillian collisional orogeny are relatively well *** contrast,accretionary orogenic processes occurring at the supercontinent periphery following Rodinia assembly are poorly *** fill this gap,we have identified metamorphic rocks in the mongolia collage of the Central Asian Orogenic Belt,where numerous data testify for meso-to Neoproterozoic magmatic *** tectono-metamorphic evolution of the periSiberian tract of the Central Asian Orogenic Belt is mainly characterized by the late Proterozoic–early Cambrian(Baikalian)***,we document here a Tonian age metamorphism at the northern part of the Precambrian Baidrag block,previously considered as a typical example of the Baikalian metamorphic *** study incorporates zircon and in-situ monazite geochronology linked to P-T modelling of Grt-Sil-Ky migmatite gneiss and Grt-St ***-Sil-Ky gneiss records initial burial to the sillimanite stability field at 720℃ and 6.0 kbar followed by further burial to the kyanite stability field at 750℃ and 9 kbar and decompression to 650℃ and 8 *** Grt-St schist records initial burial to the staurolite stability field at 620℃ and 6 kbar,followed by further burial to 590℃ and 8.5 *** monazite data yield a continuum of ^(207)Pb-corrected ^(238)U/^(206)Pb dates of ca.926–768 ma in the Grt-Sil-Ky gneiss,and ca.937–754 ma in the Grt-St *** on monazite textural positon,internal zoning,and REE patterns,the time of prograde burial to 6.0 kbar under a thermal gradient of 27–32℃/km is estimated at ca.890–853 *** is not clear whether such high-grade conditions prevailed until a phase of further burial under a geothermal gradient of 18–22℃/km dated at ca.835–815 *** late monazite recrystallization at ca.790 ma is related to ***,monazite with dates of ca.568–515 ma occur as whole grains or as rims with sharp boundaries on Tonian monaz

关键词： Central Asian Orogenic Belt Grenvillian-age metamorphism monazite in-situ U-Pb dating monazite REE composition Zircon U-Pb dating Thermodynamic modelling

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Only mothers feed mature offspring in European Ceratina bees

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Insect Science 2021年第5期28卷 1468-1481页

作者： michael mikat jitka Waldhauserova Tereza Frankova Katerina Cermakova Vojtech Broz Simon Zeman marcela Dokulilova Jakub Straka Department of Zoology Faculty of ScienceCharles UniversityPragueCzech Republic Jihlava Grammar School JihlavaCzech Republic Department of Ecology Faculty of ScienceCharles UniversityPragueCzech Republic

Parental care directed to adult offspring is uncommon in *** parental care has been documented in Xylocopinae bees(Hymenoptera:Apidae).moreover,some Ceratina bees(Xylocopinae)are known to feed mature siblings,and feeding of mature siblings is achieved by dwarf eldest daughters when mothers *** daughters are intentionally malnourished by mothers and usually originate from the first brood ***,we examined the pattern of care prov ided to young adults in three small European carpenter bees:Ceratina(Ceratina)cucurbitina,C.(Euceratina)chalybea,and C.(E.)*** of nest departures and arrivals were performed to study foraging *** detected intensive foraging behavior of mothers in all three studied ***,we did not observe regular foraging bchavior of daughters in any *** experimental removal of mothers in *** led to the emigration of young adults and did not initiate foraging activity in *** conclude that the feeding of siblings does not occur in these species unlike in the American species *** detected female-biased sex ratios in the first brood cell in *** and *** offspring in the first brood cell was smaller than other female offspring only in *** results show that a female-biased sex ratio and the small size of daughters in the first brood cell do not provide sufficient ev idence for demonstrating the existence of an altruistic daughter and also that the pattern of maternal investment is not exclusively shaped by social interactions.

关键词： foraging trip Hymenoptera maternal care provisioning sociality Xylocopinae

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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

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Harmonics in the Squirrel Cage Induction motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical machines and Systems 2024年第1期8卷 86-102页

作者： G.kovács the Ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques

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Harmonics in the Squirrel Cage Induction motor Analytic Calculation-Part Ⅰ: Differential Leakage, Attenuation, Asynchronous Parasitic Torques

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CES Transactions on Electrical machines and Systems 2023年第4期7卷 320-329页

作者： G.kovács Ganz Electric Works 1095 BudapestHungary

The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field, as well as the related differential leakage, attenuation, asynchronous parasitic torques have been discussed in great detail in the literature, but always separately, for a long time. However, systematization of the phenomenon still awaits. Therefore, it is worth summarizing the completeness of the phenomena in a single study – with a new approach at the same time-in order to reveal the relationships between them. The role of rotor slot number is emphasized much more than before. An existing, commonly used, but still impractical basic figure has been modified to more clearly demonstrate the response of the rotor for the harmonics of the stator. The need to treat differential leakage, asynchronous parasitic torques and attenuation together will be demonstrated: new formula for asynchronous parasitic torque is derived;the long-used characteristic curves for differential leakage and attenuation used separately so far was merged into one, correct curve in order to provide a correct design guide for the engineers.

关键词： Asynchronous parasitic torque Attenuation Differential leakage Squirrel cage induction motor Winding harmonics

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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

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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

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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

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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

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