996 research outputs found

    Asymptotic boundary forms for tight Gabor frames and lattice localization domains

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    We consider Gabor localization operators Gϕ,ΩG_{\phi,\Omega} defined by two parameters, the generating function ϕ\phi of a tight Gabor frame {ϕλ}λΛ\{\phi_\lambda\}_{\lambda \in \Lambda}, parametrized by the elements of a given lattice ΛR2\Lambda \subset \Bbb{R}^2, i.e. a discrete cocompact subgroup of R2\Bbb{R}^2, and a lattice localization domain ΩR2\Omega \subset \Bbb{R}^2 with its boundary consisting of line segments connecting points of Λ\Lambda. We find an explicit formula for the boundary form BF(ϕ,Ω)=AΛlimRPF(Gϕ,RΩ)RBF(\phi,\Omega)=\text{A}_\Lambda \lim_{R\rightarrow \infty}\frac{PF(G_{\phi,R\Omega})}{R}, the normalized limit of the projection functional PF(Gϕ,Ω)=i=0λi(Gϕ,Ω)(1λi(Gϕ,Ω))PF(G_{\phi,\Omega})=\sum_{i=0}^{\infty}\lambda_i(G_{\phi,\Omega})(1-\lambda_i(G_{\phi,\Omega})), where λi(Gϕ,Ω)\lambda_i(G_{\phi,\Omega}) are the eigenvalues of the localization operators Gϕ,ΩG_{\phi,\Omega} applied to dilated domains RΩR\Omega, RR is an integer and AΛ\text{A}_\Lambda is the area of the fundamental domain of the lattice Λ\Lambda.Comment: 35 page

    Eleven-year solar cycle variations in the atmosphere: observations, mechanisms and models

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    The understanding of natural and anthropogenic climatic change is an important issue in recent studies. The influence of the Sun (11-year solar cycle) as a natural variability factor on the atmosphere is discussed. Statistical studies with observational data (NCEP/NCAR re-analyses) covering four solar cycles show high correlations between the 11 -year solar signal and meteorological parameters, e.g., the geopotential heights and temperatures, in the lower stratosphere and troposphere. Studies with general circulation models (GCM) have discussed the possibility of an indirect dynamical response to direct changes in solar irradiance and ozone in the stratosphere. A physical mechanism explaining the solar influence on the atmosphere is still missing. Part of the mechanism understood so far and ideas from model and observational studies are presented

    On simultaneous limits for aggregation of stationary randomized INAR(1) processes with Poisson innovations

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    We investigate joint temporal and contemporaneous aggregation of N independent copies of strictly stationary INteger-valued AutoRegressive processes of order 1 (INAR(1)) with random coefficient α(0,1)\alpha\in(0,1) and with idiosyncratic Poisson innovations. Assuming that α\alpha has a density function of the form ψ(x)(1x)β\psi(x) (1 - x)^\beta, x(0,1)x \in (0,1), with β(1,)\beta\in(-1,\infty) and limx1ψ(x)=ψ1(0,)\lim_{x\uparrow 1} \psi(x) = \psi_1 \in (0,\infty), different limits of appropriately centered and scaled aggregated partial sums are shown to exist for β(1,0]\beta\in(-1,0] in the so-called simultaneous case, i.e., when both NN and the time scale nn increase to infinity at a given rate. The case β(0,)\beta\in(0,\infty) remains open. We also give a new explicit formula for the joint characteristic functions of finite dimensional distributions of the appropriately centered aggregated process in question.Comment: 38 page

    Numerical study of SU(2) Yang-Mills theory with gluinos

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    We report on a numerical investigation of the SU(2) gauge theory with gluinos. The low-lying spectrum in bosonic and fermionic channels is determined. Improvements of the multi-bosonic algorithm are discussed.Comment: latex, 3 pages, 4 figures; Poster presented by K. Spanderen at LATTICE9

    Surname Repetition and Isonymy in Northeastern Hungarian Marriages

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    This is the published version. Copyright 1990 Wayne State University Press.The repeated-pair (RP) approach to surnames in married couples is a measure of population subdivision resulting from the influence of lineagelike behavior in mate choice. An excess of RP over random RP implies limitations in mate choice and a reduction of genetic variability. Here we apply the RP method to data from the rural populations of Csaroda, Tiszaadony, and Tiszavid in northeastern Hungary. The results indicate small differences between RP and random RP for Tiszavid and somewhat larger differences for Tiszaadony and Csaroda. The excess of RP over random RP in Tiszavid, however, derives primarily from marriages simultaneously isonymous and repeating in only one lineage. The discrepancy between RP and random RP implies a small reduction in genetic variability

    Pitfalls during biomechanical testing — Evaluation of different fixation methods for measuring tendons endurance properties

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    The goal of the study was to find a proper technique to fix tendon grafts into an INSTRON loading machine. From 8 human cadavers, 40 grafts were collected. We removed the bone-patella tendon-bone grafts, the semitendinosus and gracilis tendons, the quadriceps tendon-bone grafts, the Achilles tendons, and the peroneus longus tendons from each lower extremity. We tested the tendon grafts with five different types of fixation devices: surgical thread (Premicron 3), general mounting clamp, wire mesh, cement fixation, and a modified clamp for an INSTRON loading machine. The mean failure load in case of surgical thread fixation was (381N ± 26N). The results with the general clamp were (527N ± 45N). The wire meshes were more promising (750N ± 21N), but did not reach the outcomes we desired. Easy slippages of the ends of the tendons from the cement encasements were observed (253N ± 18N). We then began to use Shi’s clamp that could produce 977N ± 416N peak force. We combined Shi’s clamp with freezing of the graft and the rupture of the tendon itself demonstrated an average force of 2198 N ± 773N. We determined that our modified frozen clamp fixed the specimens against high tensile forces

    Human Resource Development as a possibility for developing the most underdeveloped micro-regions of Hungary

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    One of the problems in regional development policy having been present for a long time – and presumably to remain for a long while – is developing the most underdeveloped regions. Unfortunately the difference between the developed and the underdeveloped has increased in Hungary during the last two decades – despite the strengthening regional politics. These regions are usually afflicted with multiple disadvantages, therefore it is not enough to explore and change only one cause leading to underdevelopment. It is of complex origin; the effect of several correlated factor-layers can be observed. It is an elemental thesis in case of local improvements that investing into human resources (to put it in an ordinary way, into people) and improving the conditions of the population (qualification, healthcare, standards of living, etc.) is one of the most efficient and less costly means to eliminate underdevelopment. Despite its cost-efficiency only long-term results can be expected; in many cases it takes generations to benefit from the investment. In this work we will review the conclusions and suggestions of the educational aspects of a complex Hungarian development programme

    A tuberkulózis előfordulása egy XVIII. századi váci családban

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    Two individuals of the Nigrovits family from the Vác Mummy Collection of the Hungarian Natural History Museum were the subjects of multidisciplinary, anthropological, paleopathological, radiological, paleomicrobiological and paleoproteomic studies. The father, József Nigrovits (No 29), died at the age of 55 on the 11th of November 1793; his son, Antal Nigrovits (No 54), died on the 16th of July 1803, at the age of 22. They lived in the 18th century in a small town of northern Hungary. The macroscopic examination of body No 54 showed a severely deformed neck and back region; body No 29 had no characteristic marks of any illnesses. The CT scan data of the bodies and their 3D reconstructions showed no skeletal evidence of tuberculosis, despite the positive results of their paleomicrobiological studies. The deformity of body No 54 turned to be a developmental abnormality of unknown origin, but no Pott’s gibbus was present

    Antibody-mediated inhibition of syndecan-4 dimerisation reduces interleukin (IL)-1 receptor trafficking and signalling.

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    OBJECTIVE: Syndecan-4 (sdc4) is a cell-anchored proteoglycan that consists of a transmembrane core protein and glucosaminoglycan (GAG) side chains. Binding of soluble factors to the GAG chains of sdc4 may result in the dimerisation of sdc4 and the initiation of downstream signalling cascades. However, the question of how sdc4 dimerisation and signalling affects the response of cells to inflammatory stimuli is unknown. METHODS: Sdc4 immunostaining was performed on rheumatoid arthritis (RA) tissue sections. Interleukin (IL)-1 induced extracellular signal-regulated kinases (ERK) phosphorylation and matrix metalloproteinase-3 production was investigated. Il-1 binding to sdc4 was investigated using immunoprecipitation. IL-1 receptor (IL1R1) staining on wild-type, sdc4 and IL1R1 knockout fibroblasts was performed in fluorescence-activated cell sorting analyses. A blocking sdc4 antibody was used to investigate sdc4 dimerisation, IL1R1 expression and the histological paw destruction in the human tumour necrosis factor-alpha transgenic mouse. RESULTS: We show that in fibroblasts, the loss of sdc4 or the antibody-mediated inhibition of sdc4 dimerisation reduces the cell surface expression of the IL-1R and regulates the sensitivity of fibroblasts to IL-1. We demonstrate that IL-1 directly binds to sdc4 and in an IL-1R-independent manner leads to its dimerisation. IL-1-induced dimerisation of sdc4 regulates caveolin vesicle-mediated trafficking of the IL1R1, which in turn determines the responsiveness to IL-1. Administration of antibodies (Ab) against the dimerisation domain of sdc4, thus, strongly reduces the expression IL1R1 on arthritic fibroblasts both in vitro and an animal model of human RA. CONCLUSION: Collectively, our data suggest that Ab that specifically inhibit sdc4 dimerisation may support anti-IL-1 strategies in diseases such as inflammatory arthritis

    A q-deformed nonlinear map

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    A scheme of q-deformation of nonlinear maps is introduced. As a specific example, a q-deformation procedure related to the Tsallis q-exponential function is applied to the logistic map. Compared to the canonical logistic map, the resulting family of q-logistic maps is shown to have a wider spectrum of interesting behaviours, including the co-existence of attractors -- a phenomenon rare in one dimensional maps.Comment: 17 pages, 19 figure
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