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Systematic beyond-DFT study of binary transition metal oxides

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npj Computational materials 2019年第1期5卷 124-131页

作者： Subhasish mandal Kristjan Haule Karin m.Rabe david Vanderbilt Department of Physics and Astronomy Rutgers UniversityPiscatawayNJUSA

Various methods going beyond density functional theory(DFT),such as DFT+U,hybrid functionals,meta-GGAs,GW,and DFTembedded dynamical mean field theory(eDmFT),have been developed to describe the electronic structure of correlated materials,but it is unclear how accurate these methods can be expected to be when applied to a given strongly correlated *** is thus of pressing interest to compare their accuracy as they apply to different categories of *** we introduce a novel paradigm in which a chosen set of beyond-DFT methods is systematically and uniformly tested on a chosen class of *** a first application,we choose the target materials to be the binary transition metal oxides FeO,CoO,mnO,and NiO in their antiferromagnetic phase and present a head-to-head comparison of spectral properties as computed using the various *** also compare with available experimental angle-resolved photoemission spectroscopy(ARPES),inverse-photoemission spectroscopy,and with optical *** the class of compounds studied here,we find that both B3LYP and eDmFT reproduce the experiments quite well,with eDmFT doing best,in particular when comparing with the ARPES data.

关键词： materials oxides transition

Identifying coastal towns and small cities in Denmark using global population data to support climate change adaptation

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International Journal of Digital Earth 2020年第9期13卷 1040-1054页

作者： James m.Fitton martin Lehmann david C.major Department of Planning Aalborg UniversityAalborgDenmark The Earth Institute Columbia UniversityNew YorkNYUSA

Coastal settlements face many hazards from climate ***,there has been extensive focus on developing and implementing ***,these efforts have prodominantly centred on larger *** towns and small cities(urban areas between 1000 and 100,000 people)have received little attention,despite experiencing a number of barriers to *** absence of information on the global scale of the adaptation challenge within coastal towns and small cities may have contributed to these settlements being *** paper develops a method that can be used to estimate the numbers,sizes,and locations of coastal towns and small cities worldwide from global population data(Global Human Settlement data).Denmark is used as a pilot for this method with settlements over 1000 people classified with relatively high *** method developed here represents a potentially fruitful approach to supporting coastal adaptation,as coastal towns and small cities are identifiable globally,they can be classified into *** will support an assessment of their risk to coastal hazards,and could facilitate knowledge and practice sharing between similar coastal towns and small cities.

关键词： Climate change adaptation global data coastal hazards Denmark small urban areas

The seasonal role of field characteristics on seed-eating bird abundances in agricultural landscapes

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Current Zoology 2017年第3期63卷 279-286页

作者： Emmanuel ZUFIAURRE mariano CODESIDO Agustin m. ABBA david BILENCA Grupo de Estudios sobre Biodiversidad en Agroecosistemas (6EBA) Departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires and IEGEBA (UBA- CONICET). Ciudad Universitaria Pabellon II 4° Piso (C1428EHA). Ciudad Autonoma de Buenos Aires Argentina Centro de Estudios Parasitol6gicos y de Vectores (CEPAVE) CCT-CONICET-LA PLATA-UNLP. Calle 120 entre 61 y 62 S/N La Plata (B1902CHX) Buenos Aires Argentina

In temperate agroecosystems, avian responses in abundance and distribution to landscape attributes may be exacerbated by the coupling of natural seasons and farming practices. We assessed the sea- sonal roles of field type, field use in the surroundings, and distance from a field to the nearest woodlot on the abundance of seed-eating birds in a 225,000 km2 study area in the Pampas of central Argentina. During spring-summer and autumn of 2011-2013, we randomly selected 392 fields and used transect samples to collect data on abundance and presence of seed-eating bird species. We recorded a total of 11,579 individuals belonging to 15 seed-eating bird species. We used generalized lineal mixed models to relate bird abundance to field type, field use in the surroundings, and distance to the nearest woodlot. In spring-summer （breeding season） most bird responses were associated with their nesting requirements. Species that build their nests in trees, such as eared doves Zenaida auriculata, picazuro pigeons Patagioenas picazuro, and monk parakeets myiopsitta monachus, were more abundant in fields closer to woodlots, whereas grassland yellow-finches Sicalis luteola, which nest at areas with tall grasses, were more abundant in fields with livestock use patches in the field surroundings. In au- tumn （non-breeding season）, most bird responses were associated with foraging and refuge needs. The high abundance of eared doves in crop stubbles and the association of pigeons at field surroundings dominated by croplands or at crop stubbles surrounded by livestock use fields revealed the intimate association of these species to sites with high availability of food resources. In addition, both picazuro pigeons and spot-winged pigeons Patagioenas maculosa were associated with woodlots, which provide suitable roosting sites. Our results show that in temperate agroecosystems, the relationships between field characteristics and seed-eating bird abundances vary with season.

关键词： field surroundings field type granivorous birds stubbles temperate agroecosystems woodlots.

Ribozymes and the mechanisms that underlie RNA catalysis

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 178-185页

作者： Timothy J. Wilson Yijin Liu david m. J. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozymes are widespread, and catalyze some extremely important reactions in the cell. mechanistically most fall into one of two classes, using either metal ions or general acid-base catalysis. The nucleolytic ribozymes fall into the latter class, mostly using nucleobases. A sub-set of these use a combination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozymes are still being discovered at regular intervals and we can speculate on the potential existence of ribozymes that catalyze chemistry beyond phosphoryl transfer reactions, perhaps using small-molecule coenzymes.

关键词： RNA catalysis RNA structure catalytic mechanism

A 3-D numerical study of solitary wave interaction with vertical cylinders using a parallelised particle-in-cell solver

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Journal of Hydrodynamics 2017年第5期29卷 790-799页

作者： Qiang Chen Jun Zang david m.Kelly Aggelos S.Dimakopoulos WEIR Research Unit Department of Architecture and Civil EngineeringUniversity of BathBathUK Coastal Research Laboratory International Hurricane Research CenterFlorida International UniversityMiamiUSA HR Wallingford WallingfordOxonUK

This paper aims to provide a better understanding of the interaction between solitary waves and vertical circular cylinders. This is achieved via process based numerical modelling using the parallel particle-in-cell based incompressible flow solver PICIN. The numerical model solves the Navier-Stokes equations for free-surface flows and incorporates a Cartesian cut cell method for fluid-structure interaction. Solitary waves are generated using a piston-type wave paddle. The PICIN model is first validated using a test case that involves solitary wave scattering by a single vertical cylinder. Comparisons between the present results and experimental data show good agreement for the free surface elevations around the cylinder and the horizontal wave force on the cylinder. The model is then employed to investigate solitary wave interaction with a group of eleven vertical cylinders. The wave run-up and wave forces on the cylinders are discussed.

关键词： CFD hybrid Eulerian-Lagrangian particle-in-cell solitary wave vertical cylinder

Activation-induced cell death in B lymphocytes

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Cell Research 2000年第3期10卷 179-192页

作者： DONJERKOVIC DUBRAVKA, david W scott (Department of Immunology, Holland Laboratory for the Biomedical Sciences, American Red Cross, 15601 Crabbs Branch Way, Rockville, mD, 20855. USA) DepartmentofImmunology AmericanRedCrossRockvilleMD20855USA.

Upon encountering the antigen (Ag), the immune system can either develop a specific immune response or enter a specific state of unresponsiveness, tolerance. The response of B cells to their specific Ag can be activation and proliferation, leading to the immune response, or anergy and activation-induced cell death (AICD), leading to tolerance. AICD in B lymphocytes is a highly regulated event initiated by crosslinking of the B cell receptor (BCR). BCR engagement initiates several signaling events such as activation of PLCr, Ras, and PI3K, which generally speaking, lead to survival. However, in the absence of survival signals (CD40 or IL-4R engagement), BCR crosslinking can also promote apoptotic signal transduction pathways such as activation of effector caspases, expression of pro-apoptotic genes, and inhibition of pro-survival genes. The complex interplay between survival and death signals determines the B cell fate and, consequently, the immune response.

关键词： B lymphocytes activation-induced cell death B cell receptor.

Application of Natural Antioxidants from Strawberry Tree(Arbutus unedo L.) and Dog Rose(Rosa canina L.) to Frankfurters Subjected to Refrigerated Storage

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Journal of Integrative Agriculture 2013年第11期12卷 1972-1981页

作者： mónica Armenteros david morcuende Sonia Ventanas mario Estévez Animal Production and Food Science University of ExtremaduraAv.de la Universidad s/n

The effect of the addition of natural antioxidants from strawberry tree （Arbutus unedo L.; AU） and dog rose （Rosa canina L.; RC）, in frankfurters elaborated with or without the addition of antioxidant additives （sodium ascorbate and nitrite） was studied. Six different types of experimental frankfurters were prepared depending on the addition of phenolic-rich extracts from RC and AU and the presence （P） or absence （C） of antioxidant additives. Thiobarbituric acid reactive substances （TBARS）-numbers signiifcantly increased during chilled storage of C-frankfurters while additives and fruit phenolics inhibited lipid oxidation in P-frankfurters. The amount of protein carbonyls signiifcantly increased in all treatments except in P-AU frankfurters. The discoloration process that occurred during the chilled storage was reduced by the addition of substances with proven antioxidant activity （P-frankfurters）. Texture characteristics as hardness, springiness, cohesiveness and gumminess also suffered a signiifcant deterioration in C-frankfurters. The use of phenolic fruit extracts in combination with traditional antioxidant additives is a successful strategy to enhance the oxidative stability of frankfurters without modifying their color and texture properties.

关键词： fruit phenolics protein oxidation lipid oxidation nitrite ascorbate

Quantifying geological uncertainty in metamorphic phase equilibria modelling;a monte Carlo assessment and implications for tectonic interpretations

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Geoscience Frontiers 2016年第4期7卷 591-607页

作者： Richard m.Palin Owen m.Weller david J.Waters Brendan Dyck Institute of Geosciences Johannes-Gutenberg University Mainz55128MainzGermany Geological Survey of Canada 601 Booth StreetOttawaONKIA OESCanada Department of Earth Sciences University of OxfordOxfordOX1 3ANUnited Kingdom

Pseudosection modelling is rapidly becoming an essential part of a petrologist＇s toolkit and often forms the basis of interpreting the tectonothermal evolution of a rock sample, outcrop, or geological region. Of the several factors that can affect the accuracy and precision of such calculated phase diagrams, ＂geological＂ uncertainty related to natural petrographic variation at the hand sample- and/or thin section-scale is rarely considered. Such uncertainty influences the sample＇s bulk composition, which is the primary control on its equilibrium phase relationships and thus the interpreted pressure-temper- ature （P-T） conditions of formation. Two case study examples--a garnet-cordierite granofels and a garnet-staurolite-kyanite schist--are used to compare the relative importance that geological uncer- tainty has on bulk compositions determined via （1） X-ray fluorescence （XRF） or （2） point counting techniques. We show that only minor mineralogical variation at the thin-section scale propagates through the phase equilibria modelling procedure and affects the absolute P-T conditions at which key assemblages are stable. Absolute displacements of equilibria can approach ＋l kbar for only a moderate degree of modal proportion uncertainty, thus being essentially similar to the magnitudes reported for analytical uncertainties in conventional thermobarometry. Bulk compositions determined from multiple thin sections of a heterogeneous garnet-staurolite-kyanite schist show a wide range in major-element oxides, owing to notable variation in mineral proportions. Pseudosections constructed for individual point count-derived bulks accurately reproduce this variability on a case-by-case basis, though averaged proportions do not correlate with those calculated at equivalent peak P-T conditions for a whole-rock XRF-derived bulk composition. The main discrepancies relate to varying proportions of matrix phases （primarily mica） relative to porphyroblasts （primarily staurolite and kyanit

关键词： Geological uncertainty Error Pseudosection monte Carlo mnNCKFmASHTO

Low back pain and osteoarthritis pain:a perspective of estrogen

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Bone Research 2023年第3期11卷 443-456页

作者： Huiwen Pang Shihui Chen david m.Klyne david Harrich Wenyuan Ding Sidong Yang Felicity Y.Han Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaBrisbaneQLD 4072Australia NHmRC Centre of Clinical Research Excellence in Spinal Pain Injury and HealthThe University of QueenslandSt.LuciaBrisbaneQLD 4072Australia Department of Cell and molecular Biology QIMR Berghofer Medical Research InstituteHerstonQLD 4006Australia Department of Spine Surgery The Third Hospital of Hebei Medical University139 Ziqiang RoadShijiazhuang 050051China Hebei Joint International Research Center for Spinal Diseases 139 Ziqiang RoadShijiazhuang 050051China

Low back pain(LBP)is the world's leading cause of disability and is increasing in prevalence more rapidly than any other pain *** disc(IVD)degeneration and facet joint osteoarthritis(FJOA)are two common causes of LBP,and both occur more frequently in elderly women than in other ***,osteoarthritis(OA)and OA pain,regardless of the joint,are experienced by up to twice as many women as men,and this difference is amplified during *** in estrogen may be an important contributor to these pain *** for estrogen have been found within IVD tissue and nearby joints,highlighting the potential roles of estrogen within and surrounding the IVDs and *** addition,estrogen supplementation has been shown to be effective at ameliorating IVD degeneration and OA progression,indicating its potential use as a therapeutic agent for people with LBP and OA *** review comprehensively examines the relationship between estrogen and these pain conditions by summarizing recent preclinical and clinical *** potential molecular mechanisms by which estrogen may relieve LBP associated with IVD degeneration and FJOA and OA pain are discussed.

关键词： agent degeneration pain