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Plant responses to simulated warming and drought:a comparative study of functional plasticity between congeneric mid and high elevation species

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journal of Plant Ecology 2018年第3期11卷 364-374页

作者： Elena Hamann Halil Kesselring jürg Stöcklin Botanical Institute Department of Environmental SciencesSection Plant EcologyUniversity of BaselSchönbeinstrasse 64056 BaselSwitzerland

Aims Effects of climate change,especially changes in temperatures and precipitation patterns,are particularly pronounced in alpine *** response,plants may exhibit phenotypic plasticity in key functional traits allowing short-term adjustment to novel ***,little is known about the degree of pheno-typic plasticity of high elevation species relative to mid elevation *** We transplanted 14 herbaceous perennial species from high eleva-tion into two common gardens(1050 and 2000 m.a.s.l.)in the Swiss Alps,and we examined plastic responses in key functional traits to changes in temperature and soil water *** design was replicated with 14 congeneric species from mid elevation to assess if the degree of phenotypic plasticity differs between mid and high elevation *** was assessed across two growing seasons,while aboveground biomass and specific leaf area(SLA)were measured after the first growing season,and biomass alloca-tion to belowground and reproductive structures after the ***,a phenotypic plasticity index was calculated for the func-tional traits to compare the degree of plasticity between mid and high elevation *** Findings Aboveground biomass was higher in mid elevation species relative to high elevation congeners in all treatments,yet decreased for both with elevation and ***,SLA decreased with elevation and *** mass fraction(RMF)was generally higher in high ele-vation species,and decreased with drought at the lower *** increased the allocation to reproductive structures,especially when plants were grown at their elevation of ***,no differ-ence was found in the degree of phenotypic plasticity averaged across mid and high elevation species for any of the studied functional *** results indicate that phenotypic plasticity in the focal traits did not depend on the elevation of origin of the *** was not related to

关键词： biomass allocation common garden climate change perennial herbaceous species phenotypic plasticity SLA Swiss Alps transplant experiment

Synthesis and in vitro evaluation of new diphenyl ether derivatives as serotonin transporter ligands

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Science China Chemistry 2008年第5期51卷 457-463页

作者： DEUTHER-CONRAD Winnie BRUST Peter STEINBACH jrg VERCOUILLIE johnny Institute of Interdisciplinary Isotope Research

For the development of new ligands as potential imaging agents for the serotonin transporter (SERT),a series of diphenyl ether derivatives have been synthesized,characterized,and evaluated for their in vitro binding affinities to the SERT. Among the above compounds,2-(2-((dimethylamino)methyl)-4-fluoro-phenoxy)-5-bromobenzenamine (15) and 2-(2-((dimethylamino)methyl)-4-fluorophenoxy)-5-iodobenzene amine (16) show high binding affinities for the SERT with Ki values of 0.28 and 0.20 nmol·L-1,respectively. They can be further labeled with carbon-11,fluorine-18,iodine-123 or bromine-76,and evaluated as useful imaging agents for the SERT. Moreover,the study of the structure-activity relationship (SAR) provides some useful information for the future design of new ligands.

关键词： serotonin transporter diphenyl ether imaging agents in vitro evaluation

Impact of lattice relaxations on phase transitions in a high-entropy alloy studied by machine-learning potentials

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npj Computational Materials 2019年第1期5卷 670-676页

作者： Tatiana Kostiuchenko Fritz Körmann jörg Neugebauer Alexander Shapeev Skolkovo Institute of Science and Technology Skolkovo Innovation CenterNobel St.3Moscow 143026Russia Computational Materials Design Max-Planck-Institut für Eisenforschung GmbH40237 DüsseldorfGermany Materials Science and Engineering Delft University of Technology2628 CD DelftThe Netherlands

Recently,high-entropy alloys(HEAs)have attracted wide attention due to their extraordinary materials properties.A main challenge in identifying new HEAs is the lack of efficient approaches for exploring their huge compositional *** initio calculations have emerged as a powerful approach that complements ***,for multicomponent alloys existing approaches suffer from the chemical complexity *** this work we propose a method for studying HEAs *** approach is based on the application of machine-learning potentials based on ab initio data in combination with Monte Carlo *** high efficiency and performance of the approach are demonstrated on the prototype bcc NbMoTaW *** approach is employed to study phase stability,phase transitions,and chemical short-range *** importance of including local relaxation effects is revealed:they significantly stabilize single-phase formation of bcc NbMoTaW down to room ***,a so-far unknown mechanism that drives chemical order due to atomic relaxation at ambient temperatures is discovered.

关键词： alloy relaxation entropy

What does the future bring?A look at technologies for commercial aircraft in the years 2035-2050

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Propulsion and Power Research 2014年第4期3卷 165-174页

作者： meyer j.Benzakein The Ohio State University ColumbusOhio 43210United States

Demographics and economics in the next 20 years are being ex *** reflect a significant GDP growth and with this a strong demand for commercial aircraft not only in the US and Europe but across Asia and the Middle East The demand will focus on more fuel efficient and more environmentally friendly *** progress is being made with the new regionals,narrow-body,and wide-body aircraft between now and the year *** beyond,the world will examine new airplane architectures,new changes in propulsion systems,and higher thermal and propulsion *** propulsion options will come into *** them,higher operating pressure gas generators will be developed and great attention will have to be given to highly integrated propulsion/airplane *** transfer requirements will lead to bigger gear systems as well as new hybrid *** new machines are forecasted to offer improvements in fuel efficiencies of over 40%.There are many technical challenges to make all these things *** aerospace engineers and scientists of today and tomorrow face unlimited opportunities to make a difference for what looks like a very exciting future.

关键词： Fuel efficiency High bypassratio Distributed systems Turbines Propulsion Engines Airplane

Applying Methods from Differential Geometry to Devise Stable and Persistent Air Layers Attached to Objects Immersed in Water

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journal of Bionic Engineering 2009年第4期6卷 350-356页

作者： Wilfried Konrad Christian Apeltauer jrg Frauendiener Wilhelm Barthlott Anita Roth-Nebelsick Institute for Geosciences University of Tubingen D-72016 Tubingen Germany Department of Mathematics and Statistics University of Otago Dunedin 9054 New Zealand Centre of Mathematics for Applications University of Oslo NO-0317 Oslo Norway Nees Institute for Biodiversity of Plants University of Bonn D-53115 Bonn Germany State Museum of Natural History Stuttgart Rosenstein 1 D-70191 Stuttgart Germany

We describe a few mathematical tools which allow to investigate whether air-water interfaces exist(under prescribed conditions)and are mechanically stable and temporally *** terms of physics,air-water interfaces are governed by the Young-Laplace *** they are surfaces of constant mean curvature which represent solutions of a nonlinear elliptic partial differential *** explicit solutions of this equation can be obtained only in very special cases,it is -under moderately special circumstances-possible to establish the existence of a solution without actually solving the differential *** also derive criteria for mechanical stability and temporal persistence of an air *** we calculate the lifetime of a non-persistent air ***,we apply these tools to two examples which exhibit the symmetries of 2D *** examples can be viewed as abstractions of the biological model represented by the aquatic fern Salvinia.

关键词： interfaces air layers differential geometry stability persistence Salvinia

Chemically induced local lattice distortions versus structural phase transformations in compositionally complex alloys

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npj Computational Materials 2021年第1期7卷 312-319页

作者： Yuji Ikeda Konstantin Gubaev jörg Neugebauer Blazej Grabowski Fritz Körmann Institute for Materials Science University of StuttgartStuttgartGermany Max-Planck-Institut für Eisenforschung GmbH DüsseldorfGermany Department of Materials Science and Engineering Delft University of TechnologyDelftThe Netherlands

Recent experiments show that the chemical composition of body-centered cubic(bcc)refractory high entropy alloys(HEAs)can be tuned to enable transformation-induced plasticity(TRIP),which significantly improves the ductility of these *** calls for an accurate and efficient method to map the structural stability as a function of composition.A key challenge for atomistic simulations is to separate the structural transformation between the bcc and theωphases from the intrinsic local lattice distortions in such chemically disordered *** solve this issue,we develop a method that utilizes a symmetry analysis to detect differences in the crystal *** this method in combination with ab initio calculations,we demonstrate that local lattice distortions largely affect the phase stability of Ti–Zr–Hf–Ta and Ti–Zr–Nb–Hf–Ta *** relaxation effects are properly taken into account,the predicted compositions near the bcc–hcp energetic equilibrium are close to the experimental compositions,for which good strength and ductility due to the TRIP effect are observed.

关键词： alloys ductility distortion

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Three Problems on Trigonometric Sums

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Acta Mathematica Sinica,English Series 2019年第6期35卷 721-727页

作者： Yves meyer CMLA ENS Paris-Saclay

Let Λ ? R^n be a uniformly discrete set and let C_Λ be the vector space consisting of all mean periodic functions whose spectrum is simple and contained in Λ. If Λ is a gentle set then for every f ∈ C_Λ we have f(x) = O(ω_Λ(x)) as |x| →∞ and ω_Λ(x) can be estimated(Theorem 4.1). This line of research was proposed by jean-Pierre Kahane in 1957.

关键词： Mean periodic functions almost periodic functions trigonometric sums

Ca^(2+)signaling in plant responses to abiotic stresses

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journal of Integrative Plant Biology 2022年第2期64卷 287-300页

作者： Qiuyan Dong Lukas Wallrad Bader O.Almutairi jörg Kudla Institute of Plant Biology and Biotechnology WWU MünsterSchlossplatz 7Münster48149 Germany Department of Zoology College of ScienceKing Saud UniversityRiyadhKingdom of Saudi Arabia

Adverse variations of abiotic environmental cues that deviate from an optimal range impose stresses to *** stresses severely impede plant physiology and ***,such stresses dramatically reduce crop yield and negatively impact on ecosystem stability and *** components of abiotic stresses can be,for example,suboptimal temperature and osmotic perturbations,while representative chemical facets of abiotic stresses can be toxic ions or suboptimal nutrient *** sheer complexity of abiotic stresses causes a multitude of diverse components and mechanisms for their sensing and signal ***^(2+),as a versatile second messenger,plays multifaceted roles in almost all abiotic stress responses in that,for a certain abiotic stress,Ca^(2+)is not only reciprocally connected with its perception,but also multifunctionally ensures subsequent signal ***,we will focus on salt/osmotic stress and responses to altered nutrient availability as model cases to detail novel insights into the identity of components that link stress perception to Ca^(2+)signal formation as well as on new insights into mechanisms of Ca^(2+)signal ***,we will deduce emerging conceptual consequences of these novel insights and outline arising avenues of future research on the role of Ca^(2+)signaling in abiotic stress responses in plants.

关键词： abiotic stress calcium signaling nutrient stress salt stress