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Scanning-slit topography in patients with k.ratoconus

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International Journal of Ophthalmology(English edition) 2017年第11期10卷 1686-1692页

作者： László módis Jr. gábor Németh Eszter Szalai Zsuzsa Flask. Berthold Seitz Department of Ophthalmology University of Debrecen Medical and Health Science Center Debrecen 4032 Hungary borsod-Abau-Zemplen County Hospital and University Teaching Hospital Miskolc 3526 Hungary Department of Ophthalmology Homburg Kemtoconus Center University of Saarland Homburg/Saar 66424 Germany

AIm： To evaluate the anterior and posterior corneal surfaces using scanning-slit topography and to determine the diagnostic ability of the measured corneal parameters in ***： Orbscan II measurements were tak.n in 39 k.ratoconic corneas previously diagnosed by corneal topography and in 39 healthy eyes. The central minimum, maximum, and astigmatic simulated k.ratometry（k. and anterior axial power values were determined. Spherical and cylindrical mean power diopters were obtained at the central and at the steepest point of the cornea both on anterior and on posterior mean power maps. Pachymetry evaluations were tak.n at the center and paracentrally in the 3 mm zone from the center at a location of every 45 degrees. Receiver operating characteristic（ROC） analysis was used to determine the best cut-off values and to evaluate the utility of the measured parameters in identifying patients with ***： The minimum, maximum and astigmatic simulated k.readings were 44.80±3.06 D, 47.17±3.67 D and 2.42±1.84 D respectively in k.ratoconus patients and these values differed significantly（P〈0.0001 for all comparisons） from healthy subjects. For all pachymetry measurements and for anterior and posterior mean power values significant differences were found between the two groups. moreover, anterior central cylindrical power had the best discrimination ability（area under the ROC curve=0.948）.CONCLUSION： The results suggest that scanning-slit topography and pachymetry are accurate methods both for k.ratoconus screening and for confirmation of the diagnosis.

关键词： k.ratoconus Orbscan topography pachymetry

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-tapias Iris k.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptak. of extracellular glutamate which mak.s them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/gLAST EAAT-2/gLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Contribution of the Large Helical Device Plasmas to Alfvén Eigenmode Physics in Toroidal Plasmas

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Plasma Science and Technology 2009年第4期11卷 377-380页

作者： k. TOI m. ISOBE m. OSAk.BE F. WAtaNABE k. OgAWA T. TOk.ZAWA A. SHImIZU T. IDO k. IDA, T. ITO S. mORIta k. NAgAOk. k. NARIHARA m. NISHIURA S. OHDACHI S. SAk.k.BARA k. taNAk. LHD Experiment group National Institute for Fusion Science Toki 509-5292 Japan Department of Energy Engineering and Science Nagoya University Nagoya 464-8601 Japan

In the large helical device （LHD） having three dimensional configuration, Alfven eigenmodes （AEs） destabilized by energetic ions are widely investigated using neutral beam heated plasmas with monotonic and non-monotonic rotational transform （l/2π） profiles. In a plasma with monotonic l/2π-profile, core-localized toroidicity-induced Alfven eigenmode （taE） as well as global one are often observed. With the increase in the averaged toroidal beta value, defined as the ratio of total plasma pressure to toroidal magnetic pressure, core-localized taE with low toroidal mode number becomes global. In a relatively high beta plasma with monotonic l/2π-profile, two taEs with different toroidal mode number often interact nonlinearly and generate another modes through three wave coupling. In a plasma with non-monotonic l/2π-profile generated by intense counter neutral beam current drive, reversed shear Alfven eigenmode （RSAE） and geodesic acoustic mode （CAm） excited by energetic ions were observed for the first time in a helical plasma. Nonlinear coupling was also observed between RSAE and gAm.

关键词： alpha particles Alfven eigenmodes geodesic acoustic mode helical/stellarator

Endangered lowland oak.forest steppe remnants k.ep unique bird species richness in Central Hungary

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Journal of Forestry Research 2022年第1期33卷 343-355页

作者： gáborÓnodi Zoltán Botta‑Duk.t Dániel Wink.er tamás Rédei Institute of Ecology and Botany Centre for Ecological ResearchVácrátótHungary Department of Botany and Biodiversity Research University of ViennaViennaAustria Institute of Wildlife management and Wildlife Biology University of SopronSopronHungary

The biodiversity of natural or semi-natural native,old oak.woodlands have high conservation importance,especially in landscapes of monocultural forest plantations and arable *** a wider variety of microhabitats and foraging sources,such old oak.forests can provide essential habitat for native forest bird *** conducted a study using bird point counts to compare the forest bird communities of old pedunculate oak.Quercus robur)remnants with native and non-native plantations in central Hungary in a landscape of mostly arable fields,settlements,and monocultural *** surveys were carried out in old oak.forest remnants,middle-aged oak.white poplar(Populus alba),hybrid poplar(Populus×euramericana),black.locust(Robinia pseudoacacia),and pine(Pinus spp.)*** has been carried out in nine study sites,where all six habitat types were represented(with a few exceptions),to determine total abundance,species richness,Shannon–Wiener diversity,species evenness,dominant and indicator species,and guild *** found that old oak.forest remnants were the most diverse habitats among the studied forest types,while hybrid poplar and pine plantations exhibited the lowest avian *** avian guilds most sensitive to the loss of old oak.forest remnants were ground foragers,bark.foragers,cavity-nesters,residents,and mediterranean migratory *** habitats were more diverse than non-native *** results suggest that it is important to conserve all remaining high biodiversity old oak.stands and to avoid clear-cutting of monocultural plantations in favour of practices such as mixed-species plantations,longer rotation lengths,or retention forestry.

关键词： Forest bird community Bird conservation Old oak.forest-steppe remnant Plantation forestry Forest conservation Non-native plantation

Scaling of residual displacements in terms of elastic and inelastic spectral displacements for existing SDOF systems

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Earthquak. Engineering and Engineering Vibration 2020年第1期19卷 71-85页

作者： m.g.Harik.ishnan Vinay k.gupta Department of Civil Engineering Indian Institute of Technology Kanpur

Structures undergoing inelastic displacements during earthquak. ground motions are k.own to sustain some amount of residual displacements, which may mak. them unusable or unsafe. In this study an attempt is made to estimate residual displacements for elastic-perfectly-plastic single-degree-of-freedom oscillators with a given lateral strength ratio. It is observed in the case of a class of ground motions that there are no trends in the dependence of residual displacement on the temporal features of the ground motion, and thus any estimation of residual displacements should be carried out only in the statistical sense. Statistical estimation of residual displacement spectrum via normalization with respect to inelastic or elastic spectral displacements is considered, and it is found that normalization with respect to inelastic spectral displacements is preferable. Expressions for residual displacement spectra are proposed for both types of normalizations and for the givenlateral-strength-ratio type oscillators.

关键词： residual displacement spectrum lateral strength ratio elastic-perfectly-plastic oscillator inelastic displacement spectrum elastic displacement spectrum horizontal ground motions

Intragroup social dynamics vary with the presence of neighbors in a cooperatively breeding fish

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Current Zoology 2019年第1期65卷 21-31页

作者： Jennifer k. Hellmann Ian m. Hamilton Department of Evolution Ecology and Organismal Biology The Ohio State University Columbus OH 43210 USA Department of mathematics The Ohio State University Columbus OH 43210 USA Jennifer k. Hellmann Department of Animal Biology School of Integrative Biology University of Illinois Urbana-Champaign 505 S Goodwin Ave Urbana IL 61801 USA

Conflict is an in here nt part of social life in group-living species. group members may mediate conflict through submissive and affiliative behaviors, which can reduce aggression, stabilize dominance hierarchies, and foster group cohesion. The frequency and resolution of within-group conflict may vary with the presenee of neighboring groups. Neighbors can threaten the territory or resources of the whole group, promoting behaviors that foster within-group cohesion. However, neighbors may also foster conflict of interests among group members: opportunities for subordinate dispersal may alter conflict among dominants and subordinates while opportunities for extrapair reproduction may increase conflict between mates. To understand how neighbors mediate within-group conflict in the cooperatively breeding fish Neolamprologus pulcher, we measured behavioral dynamics and social network.structure in isolated groups, groups recently exposed to neighbors, and groups with established neighbors. Aggression and submission between the dominant male and female pair were high in isolated groups, but dominant aggression was directly primarily at subordinates when groups had neighbors. This suggests that neighbors attenuate conflict between mates and foster conflict between dominants and subordinates. Further, aggression and submission between similarly sized group members were most frequent when groups had neighbors, suggesting that neighbors induce rank.related conflict. We found relatively little change in within-group affiliative network. across treatments, suggesting that the presence of neighbors does not alter behaviors associated with promoting group cohesion. Collectively, these results provide some of the first empirical insights into the extent to which intragroup behavioral network. are mediated by intergroup interactions and the broader social context.

关键词： affiliation colony conflict exponential random graph model Neolamprologus pulcher network

global Optimization Using Diffusion Perturbations with Large Noise Intensity

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Acta mathematicae Applicatae Sinica 2006年第4期22卷 529-542页

作者： g. Yin k. Yin Department of mathematics Wayne State University Detroit MI 48202 Department of Bio-based Products University of Minnesota Saint Paul MN 55108

This work.develops an algorithm for global optimization. The algorithm is of gradient ascent type and uses random perturbations. In contrast to the annealing type procedures, the perturbation noise intensity is large. We demonstrate that by properly varying the noise intensity, approximations to the global maximum can be achieved. We also show that the expected time to reach the domain of attraction of the global maximum, which can be approximated by the solution of a boundary value problem, is finite. Discrete-time algorithms are proposed; recursive algorithms with occasional perturbations involving large noise intensity are developed. Numerical examples are provided for illustration.

关键词： global optimization random perturbation diffusion

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.gHOLAmI m.EFTEk.ARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(Fgm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the Fgm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the galerk.n *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of Fgm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in Fgm porous pipes with a retaining clip, providing k.y insights for practical engineering applications in system design and optimization.

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Candidate Eclipsing Binary Systems with aδScuti Star in Northern TESS Field

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Research in Astronomy and Astrophysics 2022年第8期22卷 34-48页

作者： F.k.hraman Aliçavuş D.gümüş Ö.k.rmızıtaş Ö.Ek.nci S.Çavuş Y.T.k.ya F.Aliçavuş Çanak.ale Onsek.z mart University Faculty of Sciences and ArtsPhysics Department17100ÇanakkaleTurkey Çanak.ale Onsek.z mart University Astrophysics Research Center and Ulupnar ObservatoryTR-17100ÇanakkaleTurkey Istanbul University Institute of Graduate Studies in ScienceProgramme of Astronomy and Space Sciences34116BeyazıtIstanbulTurkey Çanak.ale Onsek.z mart University School of Graduate StudiesDepartment of PhysicsTR-17100ÇanakkaleTurkey Çanak.ale Onsek.z mart University School of Graduate StudiesDepartment of Space Sciences and TechnologiesTR-17100ÇanakkaleTurkey Çanak.ale Onsek.z mart University Faculty of Engineering Computer EngineeringTR-17100ÇanakkaleTurkey

The existence of pulsating stars in eclipsing binaries has been k.own for *** types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation *** eclipsing binaries are the only way to directly measure the mass and radius of stars with a good accuracy(≤1%),while the pulsations are a unique way to probe the stellar interior via oscillation *** are different types of pulsating stars existing in eclipsing *** of them is theδScuti ***,the k.own number ofδScuti stars in eclipsing binaries is around 90 according to the latest catalog of these *** increasing number of these k.nds of variables is important to understand the stellar structure,evolution and the effect of binarity on the ***,in this study,we focus on discovering new eclipsing binaries withδScuti component(s).We searched within the northern Transiting Exoplanet Survey Satellite(TESS)field with a visual inspection by following some criteria such as light curve shape,the existence of pulsation lik. variations in the out-of-eclipse light curve and the T_(eff) values of the *** a result of these criteria,we discovered some *** orbital variations were first removed from the TESS light curves and frequency analysis was performed on the *** luminosity,and absolute and bolometric magnitudes of the targets were calculated as *** find how much of these parameters represent the primary(more luminous)binary component,we also computed the flux density ratio of the systems by utilizing the area of the *** addition,the positions of the systems in the H-R diagram were examined considering the flux density *** a consequence of the investigation,we defined 38 candidateδScuti stars and also one maia variable in eclipsing binary systems.

关键词： (stars:)binaries:eclipsing stars:variables:delta Scuti techniques:photometric