1,398 research outputs found

    Inclusion Of The Spatial Dimension Of Population Data In Developing Policies For The Management Of AnGR –The Case Of The Heritage Sheep Breeds

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    The sustainable use of farm animal genetic resources is connected with the recognition of their contribution to the society and the environment and the assessment of the threats they are facing. The category of the heritage breeds, which are genetically distinct, geographically concentrated, adapted to their environment, commercially farmed to contribute to the local economy were considered in the frame of the HERITAGESHEEP project. The aim of this project was to deliver the potential of the heritage sheep breeds for a sustainable future for medium to low input production systems, which support local rural communities throughout Europe. This was achieved by addressing the conservation of these breeds, defining the current and future threats and developing new uses and markets for products

    Activity monitor placed at the non-paretic ankle is accurate in measuring step counts during community walking in post-stroke individuals : a validation study

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    Background: Different environmental factors may affect the accuracy of step-count activity monitors (AM). However, the validationconditions for AM accuracy largely differ from ecological environments.Objectives: To assess and compare the accuracy of AM in counting steps among poststroke individuals: during different locomotortasks, with AM placed at the nonparetic ankle or hip, and when walking in a laboratory or inside a mall.Design: Validation study.Settings: Laboratory and community settings.Participants: Twenty persons with chronic hemiparesis, independent walkers.Methods: First session: participants performed level walking (6-minute walk test [6MWT]), ramps, and stairs in the laboratory withAM placed at the nonparetic ankle and hip. Second session: participants walked a mall circuit, including the three tasks, with AMplaced at the nonparetic ankle. The sessions were video recorded.Main Outcome Measurements: Absolute difference between the steps counted by AM and the steps viewed on the video recordings(errors, %); occurrence of errors greater than 10%.Results: Median errors were similar for the 6MWT (0.86 [0.22, 7.70]%), ramps (2.17 [0.89, 9.61]%), and stairs (8.33 [2.65, 19.22]%)with AM at the ankle. Step-count error was lower when AM was placed at the ankle (8.33 [ 2.65, 19.22]%) than at the hip (9.26[3.25, 42.63]%, P = .03). The greatest errors were observed among the slowest participants (≤0.4 m/s) on ramps and stairs, whereassome faster participants (>1 m/s) experienced the greatest error during the 6MWT. Median error was slightly increased in the mallcircuit (2.67 [0.61, 12.54]%) compared with the 6MWT (0.50 [0.24, 6.79]%, P = .04), with more participants showing errors >10% dur-ing the circuit (7 vs 2, P = .05).Conclusions: Step counts are accurately measured with AM placed at the nonparetic ankle in laboratory and community settings.Accuracy can be altered by stairs and ramps among the slowest walkers and by prolonged walking tasks among faster walkers.Level of Evidence: III

    Perturbations of eigenvalues embedded at threshold: one, two and three dimensional solvable models

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    We examine perturbations of eigenvalues and resonances for a class of multi-channel quantum mechanical model-Hamiltonians describing a particle interacting with a localized spin in dimension d=1,2,3d=1,2,3. We consider unperturbed Hamiltonians showing eigenvalues and resonances at the threshold of the continuous spectrum and we analyze the effect of various type of perturbations on the spectral singularities. We provide algorithms to obtain convergent series expansions for the coordinates of the singularities.Comment: 20 page

    H^+_2$ in a strong magnetic field described via a solvable model

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    We consider the hydrogen molecular ion H2+H^+_2 in the presence of a strong homogeneous magnetic field. In this regime, the effective Hamiltonian is almost one dimensional with a potential energy which looks like a sum of two Dirac delta functions. This model is solvable, but not close enough to our exact Hamiltonian for relevant strenght of the magnnetic field. However we show that the correct values of the equilibrium distance as well as the binding energy of the ground state of the ion, can be obtained when incorporating perturbative corrections up to second order. Finally, we show that He23+ He_2^{3+} exists for sufficiently large magnetic fields

    On the spectrum of a bent chain graph

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    We study Schr\"odinger operators on an infinite quantum graph of a chain form which consists of identical rings connected at the touching points by δ\delta-couplings with a parameter α∈R\alpha\in\R. If the graph is "straight", i.e. periodic with respect to ring shifts, its Hamiltonian has a band spectrum with all the gaps open whenever α≠0\alpha\ne 0. We consider a "bending" deformation of the chain consisting of changing one position at a single ring and show that it gives rise to eigenvalues in the open spectral gaps. We analyze dependence of these eigenvalues on the coupling α\alpha and the "bending angle" as well as resonances of the system coming from the bending. We also discuss the behaviour of the eigenvalues and resonances at the edges of the spectral bands.Comment: LaTeX, 23 pages with 7 figures; minor changes, references added; to appear in J. Phys. A: Math. Theo

    Emergence of a confined state in a weakly bent wire

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    In this paper we use a simple straightforward technique to investigate the emergence of a bound state in a weakly bent wire. We show that the bend behaves like an infinitely shallow potential well, and in the limit of small bending angle and low energy the bend can be presented by a simple 1D delta function potential.Comment: 4 pages, 3 Postscript figures (uses Revtex); added references and rewritte

    Factorial Moments of Continuous Order

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    The normalized factorial moments FqF_q are continued to noninteger values of the order qq, satisfying the condition that the statistical fluctuations remain filtered out. That is, for Poisson distribution Fq=1F_q = 1 for all qq. The continuation procedure is designed with phenomenology and data analysis in mind. Examples are given to show how FqF_q can be obtained for positive and negative values of qq. With qq being continuous, multifractal analysis is made possible for multiplicity distributions that arise from self-similar dynamics. A step-by-step procedure of the method is summarized in the conclusion.Comment: 15 pages + 9 figures (figures available upon request), Late

    In-Situ Infrared Transmission Study of Rb- and K-Doped Fullerenes

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    We have measured the four IR active C60C_{60} molecular vibrations in MxC60M_{x}C_{60} (M=K,Rb)(M = K, Rb) as a function of doping xx. We observe discontinuous changes in the vibrational spectra showing four distinct phases (presumably x=0,3,4x = 0, 3, 4, and 6). The 1427cm−11427cm^{-1} and 576cm−1576cm^{-1} modes show the largest changes shifting downward in frequency in four steps as the doping increases. Several new very weak modes are visible in the x=6x=6 phase and are possibly Raman modes becoming weakly optically active. We present quantitative fits of the data and calculate the electron-phonon coupling of the 1427cm−11427cm^{-1} IR mode.Comment: 3 pages, Figure 1 included, 3 more figures available by request. REVTEX v3.0 IRC60DO
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