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Delocalization of dark and bright excitons in flat-band materials and the optical properties of V_(2)O_(5)

npj Computational Materials 2022年第1期8卷 882-890页

作者： Vitaly Gorelov Lucia reining Martin Feneberg rüdiger Goldhahn andr.schleife Walter r.L.Lambrecht Matteo Gatti LsI CNRSCEA/DRF/IRAMISÉcole PolytechniqueInstitut Polytechnique de ParisF-91120PalaiseauFrance European Theoretical spectroscopy Facility https://www.etsf.eu/ Institute of Physics Otto von Guericke University MagdeburgUniversitätsplatz 239106MagdeburgGermany Department of Materials science and Engineering University of Illinois at Urbana-ChampaignUrbanaIL61801USA Materials research Laboratory University of Illinois at Urbana-ChampaignUrbanaIL61801USA National Center for supercomputing Applications University of Illinois at Urbana-ChampaignUrbanaIL61801USA Department of Physics Case Western Reserve UniversityClevelandOH44106-7079USA synchrotron sOLEIL L’Orme des MerisiersSaint-Aubin BP 48F-91192Gif-sur-YvetteFrance

The simplest picture of excitons in materials with atomic-like localization of electrons is that of Frenkel excitons,where electrons and holes stay close together,which is associated with a large binding ***,using the example of the layered oxide V_(2)O_(5),we show how localized charge-transfer excitations combine to form excitons that also have a huge binding energy but,at the same time,a large electron-hole distance,and we explain this seemingly contradictory *** anisotropy of the exciton delocalization is determined by the local anisotropy of the structure,whereas the exciton extends orthogonally to the chains formed by the crystal ***,we show that the bright exciton goes together with a dark exciton of even larger binding energy and more pronounced *** findings are obtained by combining first principles many-body perturbation theory calculations,ellipsometry experiments,and tight binding modelling,leading to very good agreement and a consistent *** explanation is general and can be extended to other materials.

关键词： structure anisotropy finding

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surface movement above old coal longwalls after mine closure

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International Journal of Mining science and Technology 2017年第3期27卷 481-490页

作者： andré Vervoort Pierre-Yves Declercq Department of Civil Engineering KU Leuven Leuven 3001 Belgium Geological survey of Belgium Royal Belgian Institute of Natural Sciences Brussels 1000 Belgium

Although most subsidence occurs in the months and years after mining by the longwall method, surface movement is still occurring many decades after the mining. The aim of the study is to quantify the long term behavior. satellite data(radar-interferometry) were analyzed to study an area of about 2 km^2 during the 18 years following the closure of the underground infrastructure and the flooding of the underground workings and rock mass. It was observed that, on average, a residual downward movement took place till 7–12 years after the closure, followed by a clear uplift. However, the first signs of an uplift occurred in certain sub-areas 3–4 years after the closure. Zones within the area studied were identified with either larger or smaller movements. However, the spatial variation of the surface subsidence or uplift could not be directly explained by the characteristics of mining.

关键词： Coal mining surface movement subsidence Uplift radar-interferometry

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Improved shape hardening function for bounding surface model for cohesive soils

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Journal of rock Mechanics and Geotechnical Engineering 2014年第4期6卷 328-337页

作者： andr.s Nieto-Leal Victor N.Kaliakin Department of Civil & Environmental Engineering University of Delaware Newark DE 19716 USA Department of Civil Engineering Universidad Militar Nueva Granada Bogotá Colombia

A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one.

关键词： Constitutive model Bounding surface plasticity shape hardening function Clay

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The immune hunger games:the effects of fasting on monocytes

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Cellular & Molecular Immunology 2023年第10期20卷 1098-1100页

作者： Jorge Domínguez-andr.s Holger reinecke Yahya sohrabi Department of Internal Medicine and radboud Center for Infectious Diseases Radboud University Nijmegen Medical Centre6500HBNijmegenthe Netherlands Department of Cardiology I-Coronary and Peripheral Vascular Disease Heart FailureUniversity Hospital MünsterWestfälische Wilhelms-UniversitätMünsterGermany Institutes of Molecular Genetics of the Czech Academy of sciences PragueCzech Republic Department of Medical Genetics Third Faculty of MedicineCharles UniversityPragueCzech Republic

Currently,different types of fasting are becoming increasingly popular for their potential health benefits,particularly in improving cardiometabolic ***,how these practices affect immune function is not well *** a recent study published in Immunity,Janssen et *** into the complex relationship among fasting,refeeding,and the immune *** fasting caused monocyte homing in bone marrow(BM),refeeding escalated monocyte counts in the circulation but altered immune responses to bacterial infection[1].

关键词： becoming fasting she

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Demodulating the response of Optical Fibre Long-Period Gratings： Genetic Algorithm Approach

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Chinese Physics Letters 2006年第9期23卷 2480-2482页

作者： P. s. andré r. A. sá. Ferreira C. M. L. Correia H. Kalinowshy 忻向军 J.L.Pinto Instituto de Telecomunicaoes Universidade de A veiro Campus de Santiago 3810-193 A veiro Portugal Departamento de Fisica Universidade de A veiro Campus de Santiago 3810-193 A veiro Portugal Centro de Investigacao em Materiais Compositos e Cergmicos CICECO Universidade de A veiro Campus de Santiago 3810-193 A veiro Portugal Centro Federal de Educao Tecnologica do Parana A v. sere de setembro 3165 80230-901 Curitiba-PR Brasil school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876

The extraction of the physical parameters of long period gratings from the spectral response is not an easy process. We present a demodulation technique to synthesize the physical parameters of a long period grating recorded in an optical fibre. The demodulation is achieved through the implementation of a genetic algorithm. The extracted parameters are in agreement with the typical values known for long period gratings.

关键词： sENsOrs INDEX

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A novel surface mesh deformation method for handling wing-fuselage intersections

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Chinese Journal of Aeronautics 2017年第1期30卷 264-273页

作者： Mario Jaime Martin-Burgos Daniel González-Juárez Esther andr.s-Pérez Fluid Dynamics Branch National Institute for Aerospace Technology (INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Engineering Department lngenieria de Sistemas para la Defensa de Espana (ISDEFE-INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Technical University of Madrid (UPM) Ronda de Valencia 3 28012 Madrid Spain

This paper describes a method for mesh adaptation in the presence of intersections, such as wing-fuselage. Automatic optimization tools, using Computational Fluid Dynamics（CFD） simulations, face the problem to adapt the computational grid upon deformations of the boundary surface. When mesh regeneration is not feasible, due to the high cost to build up the computational grid, mesh deformation techniques are considered a cheap approach to adapt the mesh to changes on the geometry. Mesh adaptation is a well-known subject in the literature; however, there is very little work which deals with moving intersections. Without a proper treatment of the intersections,the use of automatic optimization methods for aircraft design is limited to individual *** proposed method takes advantage of the CAD description, which usually comes in the form of Non-Uniform rational B-splines（NUrBs） patches. This paper describes an algorithm to recalculate the intersection line between two parametric surfaces. Then, the surface mesh is adapted to the moving intersection in parametric coor.inates. Finally, the deformation is propagated through the volumetric mesh. The proposed method is tested with the DLr F6 wing-body configuration.

关键词： Aerodynamic shape optimization Computational fluid dynamics Computer-assisted design Geometry parameterizationMesh deformation Non-Uniform rational B-splines

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Punctual mutations in 23s rrNA gene of clarithromycinresistant Helicobacter pylori in Colombian populations

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World Journal of Gastroenterology 2018年第14期24卷 1531-1539页

作者： andr.s Jenuer Matta Diana Carolina Zambrano Alvaro Jairo Pazos registro Poblacional de Cáncer de Cali Department of Pathology School of Medicine Universidad del Valle Faculty of Education and sports sciences Institución Universitaria Escuela Nacional del Deporte Department of Biology Universidad de Nari?o

AIM To characterize punctual mutations in 23s rrNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic *** PCr products of 23s rrNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC) population: TumacoColombia, and 5 from a high-risk population: TuquerresColombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23s rrNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin ***23s rrNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, C1770 T, C1954 T1, and G1827 C in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 C, A2144 G and C2196 T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23s rrNA gene in clarithromycin-resistant H. pylori(κ = 0.71).CONCLUsION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23s rrNA gene in clarithromycinresistant H. pylori.

关键词： Clarithromycin In vitro resistance Point mutation Helicobacter pylori Gastric cancer 23s rrNA

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An Andean tectonic cycle:From crustal thickening to extension in a thin crust(34°-37°sL)

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Geoscience Frontiers 2014年第3期5卷 351-367页

作者： Victor A.ramos Vanesa D.Litvak andr.s Folguera Mauro spagnuolo Laboratorio de Tectonica Andina del Instituto de Estudios Andinos Don Pablo GroeberCONICET-Universidad de Buenos AiresArgentina

several orogenic cycles of mountain building and subsequent collapse associated with periods of shal- lowing and steepening of subduction zones have been recognized in recent years in the Andes. Most of them are characterized by widespread crustal delamination expressed by large calderas and rhyolitic flare-up produced by the injection of hot asthenosphere in the subduction wedge. These processes are related to the increase of the subduction angle during trench roll-back. The Payenia paleoflat-slab, in the southern Central Andes of Argentina and Chile （34° -37°s） recorded a complete cycle from crustal thickening and mountain uplift to extensional collapse and normal faulting, which are related to changes in the subduction geometry. The early stages are associated with magmatic expansion and migration, subsequent deformation and broken foreland. New ages and geochemical data show the middle to late Miocene expansion and migration of arc volcanism towards the foreland region was associated with important deformation in the Andean foothills. However, the main difference of this orogenic cycle with the previously described cycles is that the steepening of the oceanic subducted slab is linked to basaltic flooding of large areas in the retroarc under an extensional setting. Crustal delamination is concentrated only in a narrow central belt along the cordilleran axis. The striking differences between the two types of cycles are interpreted to be related to the crustal thickness when steepening the subducting slab, The crustal thickness of the Altiplano is over 60-80 km, whereas Payenia is less than 42 km in the axial part, and near 30 km in the retroarc foothills. The final extensional regime associated with the slab steepening favors the basaltic flooding of more than 8400 km3 in an area larger than 40,000 km2, through 800 central vents and large fissures. These characteristics are unique in the entire present-day Andes.

关键词： Andes retroarc magmatism Basaltic floods Crustal delamination Flat-slab

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Presence of Fleischer ring and prominent corneal nerves in keratoconus relatives and normal controls

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 922-927页

作者： gnes Kriszt Gergely Losonczy andr.s Berta Lili Takcs Department of Ophthalmology University of Debrecen Clinical Center

AIMTo examine the occurrence of commonly known clinical signs of keratoconus (KC), i.e. Fleischer ring, prominent corneal nerves and thinning, among unaffected family members of KC patients and healthy control *** of both eyes of 117 relatives of KC patients having no manifest disease based on videokeratography indices (KC relatives), and 142 controls were used for Pearson correlation and t-test statistics. Correlation of Fleischer ring, prominent corneal nerves and central pachymetry data were tested with each other and with videokeratography indices (KsI, KIsA, 3 and 6 mm Fourier asymmetry, and I-s).rEsULTsA moderate correlation was found between Fleischer ring and all examined topographical indices. Most important correlation was present with 6 mm Fourier asymmetry, and corneal pachymetry (r=0.272, Pr=-0.234, P=0.027, respectively). similar correlations were found with prominent corneal nerves (r=0.234, Pr 6 mm Fourier asymmetry and r=-0.235, P=0.0265 for pachymetry). KC family members who exhibited Fleischer ring or prominent nerves had thinner and more asymmetric corneas than those without Fleischer ring or prominent corneal nerves (Pr pachymetry and topographic indices with t-test and Mann-Whitney rank sum test). Though rarely, Fleischer ring and prominent corneal nerves occurred among normal controls, indicating the existence of forme fruste cases in the normal population. Control subjects, who had corneal Fleischer ring or prominent nerves had corneas more similar to KC than other controls (t-test: increased KsI and KIsA, P=0.048 and 0.012, respectively).CONCLUsIONIn KC family members and healthy individuals, Fleischer ring and prominent corneal nerves are associated with features of KC and may suggest a possibility of forme fruste KC. searching for the possible presence of Fleischer ring or prominent nerves on the cornea may help in the decision whether or not to diagnose subclinical KC in

关键词： forme fruste/subclinical keratoconus Fleischer ring corneal nerves corneal thinning videokeratographic indices iatrogenic keratectasia

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Upward surface movement above deep coal mines after closure and flooding of underground workings

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International Journal of Mining science and Technology 2018年第1期28卷 53-59页

作者： andré Vervoort Pierre-Yves Declercq Department of Civil Engineering KU Leuven Geological survey of Belgium Royal Belgian Institute of Natural Sciences

After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward *** most surface movement(i.e., subsidence) occurs in the months and years after mining by the longwall method, surface movement still occurs many decades after mining is *** the closure and flooding of underground excavations and surrounding rock, this movement was *** paper focuses on quantifying the upward movement in two neighboring coal mines(Winterslag and Zwartberg, Belgium).The study is based on data from a remote sensing technique: interferometry with synthetic aperture radar(INsAr).The results of the study show that the rate of upward movement in the decade after closure is about 10 mm/year on *** upward movements are not linked directly to the past exploitation directly underneath a *** amounts of subsidence at specific locations are linked mainly to their positions relative to an inverse trough shape situated over the entire mined-out areas and their immediate *** features, such as geological faults, can have a secondary effect on the local variation of the *** processes of subsidence and uplift are based on completely different *** is initiated by a caving process, while the process of uplift is clearly linked to flooding.

关键词： Coal mining surface movement subsidence Uplift radar-interferometry

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