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Discontinuous Galerkin Methods for a Class of Nonvariational Problems

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Communications on Applied Mathematics and Computation 2022年第2期4卷 634-656页

作者： andreas Dedner Tristan Pryer Mathematics Institute University of WarwickCoventry CV47ALUK Department of Mathematical Sciences University of BathBath BA27AYUK

We extend the fnite element method introduced by Lakkis and Pryer(SIAM ***.33(2):786–801,2011)to approximate the solution of second-order elliptic problems in nonvariational form to incorporate the discontinuous Galerkin(DG)*** is done by viewing the“fnite element Hessian”as an auxiliary variable in the *** the fnite element Hessian in a discontinuous setting yields a linear system of the same size and having the same sparsity pattern of the compact DG methods for variational elliptic ***,the system matrix is very easy to assemble;thus,this approach greatly reduces the computational complexity of the discretisation compared to the continuous *** conduct a stability and consistency analysis making use of the unifed frameworkset out in Arnold et al.(SIAM ***.39(5):1749–1779,2001/2002).We also give an a posteriori analysis of the method in the case where the problem has a strong *** analysis applies to any consistent representation of the fnite element Hessian,and thus is applicable to the previous works making use of continuous Galerkin *** evidence is presented showing that the method works well also in a more general setting.

关键词： Nonvariational problems Discontinuous Galerkin Error estimates Adaptivity

Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 340-353页

作者： ZHAO Wenjin WANG Nianzhong ZHU Min Ulrich mann Ulrich HERTEN andreas LǖKE Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Institute of Chemistry and Dynamics of the Geosphere ICG-4 Research Center Juelich GmbH D-52425 Juelich Germany

Carbon isotope （δ13Corg） analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as -25.2‰ （Xishancun） and -19.9‰（Putonggou） in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti （only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna）. These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary （SDB） at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point （GSSP） in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation （between sample QX-20 and sample QX-21） in the Xishancun Section and the lower part of the Xiaputonggou Formation （between sample ZP-09 and sample ZP-10） in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with no

关键词： Carbon isotope stratigraphy microvertebrate assemblages Silurian-Devonian Boundary marine and non- marine stratigraphic correlation South China

Between plaza and peak: a montological perspective on verticality and urbanization in highland Peru

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Journal of Mountain Science 2023年第10期20卷 2783-2803页

作者： andreas HALLER Domenico BRANCA Deyvis CANO Institute for Interdisciplinary Mountain Research Austrian Academy of SciencesInnsbruck 6020Austria Department of Humanities and Social Sciences University of SassariSassari 07100Italy Programa Académico de Ingeniería Ambiental Universidad de HuánucoHudnuco 10001Peru

Under the influence of concentrated and extended urbanization,Andean cities and the different altitudinal zones of their“hinterlands”are experiencing profound changes in land cover—from the central plazas up to the highest *** complex regional-geographic characteristics of these socioecological systems,such as the vertical complementarity of land use,require a montological perspective on verticality and urbanization:it transcends disciplinary approaches and can be crucial to properly interpret the trajectories of land cover change and formulate hypotheses for future practiceoriented *** trajectories of land cover change characterized altitudinal zones of Andean cities and their surroundings over the last three decades?Are there similarities that allow for the formulation of more general hypotheses?Using the Peruvian cases of Cusco and Huaraz,and combining a traditional altitudinal zonation model of land use in Peru with direct field observations and GIS-based analyses of remotely sensed data from 1991,2001,2011,and 2021,this study identifies the main trajectories of land cover change in the Quechua(>2300–3500 m),Suni(>3500–4000 m),and Puna(>4000–4800 m)regions—and finds insightful similarities between Cusco and Huaraz:(1)an impressive area of built-up land substitutes grassland in the Quechua,which,following regional altitudinal zonation models,is characterized by irrigated and rain-fed cropland;(2)an unexpected expansion of irrigated cropland takes place in the Suni,which,in theory,often lacks irrigation infrastructure and is mostly used for rain-fed tuber cultivation;and(3)a clear change from“other land”to grassland occurs in the Puna—where grassland is thought to predominate,anyway,since pre-Hispanic *** that these changes reflect the interplay between speculative fallow,agricultural intensification,and ecological restoration,the results can be read as vertically complementary,local manifestations of concentrated and extended urba

关键词： Mountain cities Mountain agriculture Land use change Land cover change Rural-urban linkages Montology

Zinc-ion hybrid supercapacitors with ultrahigh areal and gravimetric energy densities and long cycling life

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Journal of Energy Chemistry 2022年第7期31卷 480-491,I0012页

作者： Ahmad Amiri M.Naraghi andreas A.Polycarpou J.Mike walker’66 mechanical engineering department texas a&m universitycollege stationTX 77843USA department of aerospace engineering texas a&m universitycollege stationTX 77843USA

Zinc ion hybrid supercapacitor (ZIHSC) with promising energy and power densities is an excellent answer to the ever-growing demand for energy storage *** restricted lifespan due to the dendrite formation on metallic zinc (Zn) is one of the main ***,we investigate the electrochemical capability of oxygen-enriched porous carbon nanofibers (A-CNF) and nitrogen,oxygen-enriched porous carbon nanofibers (N-CNF) cathode materials for structural *** this end,a series of samples with different chemical compositions (N and O contents) are prepared to present deep insight into the electrochemical mechanism between N/O doping and Zn-ion *** as-prepared ZIHSC in the presence of N-CNF cathode and Zn Cl_(2) electrolyte offers a battery-level gravimetric energy density of 143.2 Wh kg^(-1)at a power density of 367.1 W kg^(-1).The free-standing N-CNF electrodes in ZIHSCs enjoy delivering an outstanding areal energy density of 110.4μWh cm^(-2)at 0.24 m W cm^(-2),excellent rate capability,and noticeable cycling stability over 10,000 cycles at 10 A g^(-1)with less than 7%*** was also concluded that active pyrrolic N dopants might deliver and facilitate more pseudocapacitance in ZIHSCs than other N configurations,resulting in higher adsorption/desorption and insertion/extraction process of Zn Cl^(+).Taking advantage of the beneficial properties of a free-standing continuous cathode,this novel generation of structural cathode material offers high areal and gravimetric energy densities and mechanical properties in a single zinc-ion-based package.

关键词： Porous carbon nanofibers Zinc chloride electrolyte Zinc ion hybrid supercapacitors Nitrogen-doping Activation Energy density

Highly reactive chemicals meet haploidization

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Molecular Plant 2022年第6期15卷 937-939页

作者： Alevtina Ruban andreas Houben KWS SAAT SE&Co.KGaA Grimsehlstraße 3137574 EinbeckGermany Leibniz Institute of Plant Genetics and Crop Plant Research(IPK)Gatersleben Corrensstraße 306466 Stadt SeelandGermany

The ability to generate(di)haploid plants has provided a strategy to significantly accelerate the crop-breeding *** major advantage of doubled haploids to breeders lies in the simultaneous genetic fixation at every locus within a single generational ***,each doubled haploid(DH)represents a pure line that can be further evaluated for the range of agronomically important *** have been induced mainly through the generation of plants from cultivated gametophytic(haploid)cells,i.e.,in vitro haploid technologies,or through the selective loss of one parental chromosome set upon inter-or intraspecific hybridization,i.e.,in vivo haploid ***,in many crop species,efficient haploid technology is not yet available or only applicable to a limited number of genotypes(reviewed by Jacquier et al.,2020).Due to the limits and costs of current haploid technologies,plant breeders are highly interested in any methodological *** efficient DH production system with low genotype dependency based on the in vivo approach exists so far only in *** haploid-inducing capacity of the inbred line Stock6,originally reported to cause haploid induction rates of 2.3%–3.2%(Coe,1959),was further increased to above 8%in various inducer breeding programs(reviewed by Jacquier et al.,2020).The underlying genetics of the in vivo haploid induction process is quite ***,in recent years significant advances have been made in elucidating the major players.

关键词： breeding doubled Highly

Diverging rationalities between forest fire management services and the general public after the 21st-century mega-fires in Greece

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Journal of Forestry Research 2022年第2期33卷 553-564页

作者： andreas Y.Troumbis Kostas Kalabokidis Palaiologos Palaiologou Department of Environment University of the Aegean81100 MytileneLesvos IslandGreece Department of Geography University of the Aegean81100 MytileneLesvos IslandGreece

Wildfire risk related to hazards on people and assets is expected to increase in the face of climate change,especially in fire-prone environments such as the Mediterranean *** rationalities,i.e.,the complex profile of multi-thematic,wildfire-related perceptions that collectively characterize and quantify all of a society’s responses,its interrelations,and influence on its insights,are of primary importance to understand the degree of preparedness and the direction that wildfire management policies are *** is a country that suffered mega-wildfire events during the first years of the twenty-first *** paper presents a scheme of advanced multivariate statistical procedures applied on standard social survey questionnaires to uncover different or similar rationalities between fire management services and the general ***-centered versus message-oriented rationalities is *** differ mainly on the priorities attributed to strengthening personnel and equipment capacities versus the need for public education and *** are evaluated against the needs of long-term risk assessment and forest management policies in *** main conclusion is that Greek society,although traumatized by recent fire disasters,is not yet prepared for long-term strategic forestry adaptation and planning.

关键词： Wildfire Qualitative research Rationality Fire governance Public Perception Risk assessment

Tribological behaviour of Ti_(3)C_(2)T_(x) nano-sheets: Substrate-dependent tribo-chemical reactions

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Friction 2023年第8期11卷 1522-1533页

作者： Alberto ROTA Nicolas BELLINA Bo WANG andreas ROSENKRANZ Dipartimento di Scienze Fisiche Informatiche e MatematicheUniversitàdi Modena e Reggio EmiliaModena 41125Italy CNR-Istituto di Nanoscienze Centro S3Modena 41125Italy Centro Interdipartimentale per la Ricerca Applicata e i Servizi nel settore della Meccanica Avanzata e della Motoristica Universitàdi Modena e Reggio EmiliaModena 41125Italy Key Laboratory of Marine New Materials and Related Technology Zhejiang Key Laboratory of Marine Materials and Protection TechnologyNingbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China Department of Chemical Engineering Biotechnology and MaterialsUniversity of ChileSantiago 8370456Chile

MXenes,a newly emerging class of layered two dimensional(2D)materials,are promising solid lubricants due to their 2D structure consisting of weakly-bonded layers with a low shear strength and ability to form beneficial *** work aims at evaluating for the first time MXenes lubrication performance and tribofilm formation ability on different metallic substrates(mirror-lapped Fe and Cu discs).After depositing MXenes via ethanol(1 wt%)on the substrates,pronounced differences in the resulting substrate-dependent frictional evolution are *** MXenes are capable to reduce friction for both substrates after the full evaporation of ethanol,MXenes lubricating effect on Cu is long-lasting,with a 35-fold increased lifetime compared to *** spectra acquired in the wear-tracks of the substrates and counter-bodies reveal notable differences in the friction-induced chemical changes depending on the substrate *** case of Fe,the progressive failure of MXenes lubrication generates different Fe oxides on both the substrate and the ball,resulting in continuously increasing friction and a poor lubrication *** Cu,sliding induces the formation of a Ti_(3)C_(2)-based tribofilm on both rubbing surfaces,enabling a long-lasting lubricating *** work boosts further experimental and theoretical work on MXenes involved tribo-chemical processes.

关键词： Mxenes Ti_(3)C_(2)T_(x) nano-sheets coefficient of friction Raman spectroscopy tribochemistry

Data-driven prediction of plate velocities and plate deformation of explosive reactive armor

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Defence Technology（防务技术） 2022年第12期18卷 2141-2149页

作者： Marvin Becker andreas Klavzar Thomas Wolf Melissa Renck Institute of Saint-Louis 5 Rue du Général Cassagnou68330Saint LouisCedexFrance Ecole Centrale de Lille CitéScientifique59651Villeneuve d'AscqCedexFrance

Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge *** mobility,the aim is to design a protection system with a minimal amount of required *** efficiency of an ERA is sensitive to the impact position and the timing of the ***,different designs have to be tested for several impact scenarios to identify the best *** analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed *** ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with *** ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in *** a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given ***,a measure for the effectiveness of an ERA can be ***,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.

关键词： Artificial neural network Explosive reactive armor Finite element simulation Particle simulation Flash X-ray

Cancer cells evade ferroptosis: sex hormone-driven membrane-bound O-acyltransferase domain-containing 1 and 2 (MBOAT1/2) expression

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Signal Transduction and Targeted Therapy 2023年第10期8卷 4424-4425页

作者： Alexia Belavgeni Wulf Tonnus andreas Linkermann Division of Nephrology Department of Internal Medicine IUniversity Hospital Carl Gustav Carus at the Technische Universitat DresdenDresdenGermany Division of Nephrology Department of MedicineAlbert Einstein College of MedicineBronxNYUSA

In a recent manuscript published in Cell,Liang et *** novel ferroptosis regulators,membrane-bound O-acyltransferase domain-containing 1 and 2(MBOAT1/2).1 These findings may have implications for ferroptosis-based canc... 详细信息

关键词： al. T1/2 Cancer