2,169 research outputs found

    IL-6 Plasma Levels Correlate With Cerebral Perfusion Deficits and Infarct Sizes in Stroke Patients Without Associated Infections

    Get PDF
    Introduction: We aimed to investigate several blood-based biomarkers related to inflammation, immunity, and stress response in a cohort of patients without stroke-associated infections regarding their predictive abilities for functional outcome and explore whether they correlate with MRI markers, such as infarct size or location. Methods: We combined the clinical and radiological data of patients participating in two observational acute stroke cohorts: the PREDICT and 1000Plus studies. The following blood-based biomarkers were measured in these patients: monocytic HLA-DR, IL-6, IL-8, IL-10, LBP, MRproANP, MRproADM, CTproET, Copeptin, and PCT. Multiparametric stroke MRI was performed including T2*, DWI, FLAIR, TOF-MRA, and perfusion imaging. Standard descriptive sum statistics were used to describe the sample. Associations were analyzed using Fischer's exact test, independent samples t-test and Spearmans correlation, where appropriate. Results: Demographics and stroke characteristics were as follows: 94 patients without infections, mean age 68 years (SD 10.5), 32.2% of subjects were female, median NIHSS score at admission 3 (IQR 2-5), median mRS 3 months after stroke 1 (IQR 0-2), mean volume of DWI lesion at admission 5.7 ml (SD 12.8), mean FLAIR final infarct volume 10 ml (SD 14.9), cortical affection in 61% of infarctions. Acute DWI lesion volume on admission MRI was moderately correlated to admission/maximum IL-6 as well as maximum LBP. Extent of perfusion deficit and mismatch were moderately correlated to admission/maximum IL-6 levels. Final lesion volume on FLAIR was moderately correlated to admission IL-6 levels. Conclusion: We found IL-6 to be associated with several parameters from acute stroke MRI (acute DWI lesion, perfusion deficit, final infarct size, and affection of cortex) in a cohort of patients not influenced by infections

    Magnetodielectric coupling of infrared phonons in single crystal Cu2_{2}OSeO3_{3}

    Get PDF
    Reflection and transmission as a function of temperature have been measured on a single crystal of the magnetoelectric ferrimagnetic compound Cu2_{2}OSeO3_{3} utilizing light spanning the far infrared to the visible portions of the electromagnetic spectrum. The complex dielectric function and optical properties were obtained via Kramers-Kronig analysis and by fits to a Drude-Lortentz model. The fits of the infrared phonons show a magnetodielectric effect near the transition temperature (Tc60T_{c}\sim 60~K). Assignments to strong far infrared phonon modes have been made, especially those exhibiting anomalous behavior around the transition temperature

    Adaptive self-organization in a realistic neural network model

    Full text link
    Information processing in complex systems is often found to be maximally efficient close to critical states associated with phase transitions. It is therefore conceivable that also neural information processing operates close to criticality. This is further supported by the observation of power-law distributions, which are a hallmark of phase transitions. An important open question is how neural networks could remain close to a critical point while undergoing a continual change in the course of development, adaptation, learning, and more. An influential contribution was made by Bornholdt and Rohlf, introducing a generic mechanism of robust self-organized criticality in adaptive networks. Here, we address the question whether this mechanism is relevant for real neural networks. We show in a realistic model that spike-time-dependent synaptic plasticity can self-organize neural networks robustly toward criticality. Our model reproduces several empirical observations and makes testable predictions on the distribution of synaptic strength, relating them to the critical state of the network. These results suggest that the interplay between dynamics and topology may be essential for neural information processing.Comment: 6 pages, 4 figure

    ESR Study of (C_5H_{12}N)_2CuBr_4

    Full text link
    ESR studies at 9.27, 95.4, and 289.7 GHz have been performed on (C5_5H12_{12}N)2_2CuBr4_4 down to 3.7 K. The 9.27 GHz data were acquired with a single crystal and do not indicate the presence of any structural transitions. The high frequency data were collected with a polycrystalline sample and resolved two absorbances, consistent with two crystallographic orientations of the magnetic sites and with earlier ESR studies performed at 300 K. Below BC1=6.6B_{C1}=6.6 T, our data confirm the presence of a spin singlet ground state.Comment: 2 pages, 4 figs., submitted 23rd International Conference on Low Temperature Physics (LT-23), Aug. 200

    Magnetic Studies of End-Chain Spin Effects in the Haldane Gap Material Ni(C3H10N2)2N3(ClO4)

    Full text link
    Electron spin resonance (ESR), at 9, 94, and 190 GHz, and magnetization studies on polycrystalline, powder, and ultrafine powder samples of Ni(C3H10N2)2N3(ClO4) (NINAZ) have revealed several effects arising from the Haldane phase. Using the g value of the end-chain spin SS as determined by ESR, our results confirm that the end-chain spins are S=1/2 and show no evidence for S=1 end-chains. In addition, the ESR signals reveal spectral weight consistent with a model describing interactions between the end-chain spins on the shortest chains and between the magnetic excitations on the chains and the end-chain spins.Comment: Paper revised with additional data, to be published in Physical Review

    Ultrasound attenuation and a P-B-T phase diagram of superfluid 3He in 98% aerogel

    Full text link
    Longitudinal sound attenuation measurements in superfluid 3He in 98% aerogel were conducted at pressures between 14 and 33 bar and in magnetic fields up to 4.44 kG. The temperature dependence of the ultrasound attenuation in the A-like phase was determined for the entire superfluid region exploiting the field induced meta-stable A-like phase at the highest field. In the lower field, the A-B transition in aerogel was identified by a smooth jump in attenuation on both cooling and warming. Based on the transitions observed on warming, a phase diagram as a function of pressure (P), temperature (T) and magnetic field (B) is constructed. We find that the A-B phase boundary in aerogel recedes in a drastically different manner than in bulk in response to an increasing magnetic field. The implications of the observed phase diagram are discussed.Comment: 9 pages, 13 figures, accepted to PR

    Isobaric multiplet mass equation in the A=31A=31 T=3/2T = 3/2 quartets

    Full text link
    The observed mass excesses of analog nuclear states with the same mass number AA and isospin TT can be used to test the isobaric multiplet mass equation (IMME), which has, in most cases, been validated to a high degree of precision. A recent measurement [Kankainen et al., Phys. Rev. C 93 041304(R) (2016)] of the ground-state mass of 31^{31}Cl led to a substantial breakdown of the IMME for the lowest A=31,T=3/2A = 31, T = 3/2 quartet. The second-lowest A=31,T=3/2A = 31, T = 3/2 quartet is not complete, due to uncertainties associated with the identity of the 31^{31}S member state. Using a fast 31^{31}Cl beam implanted into a plastic scintillator and a high-purity Ge γ\gamma-ray detection array, γ\gamma rays from the 31^{31}Cl(βγ)(\beta\gamma)31^{31}S sequence were measured. Shell-model calculations using USDB and the recently-developed USDE interactions were performed for comparison. Isospin mixing between the 31^{31}S isobaric analog state (IAS) at 6279.0(6) keV and a nearby state at 6390.2(7) keV was observed. The second T=3/2T = 3/2 state in 31^{31}S was observed at Ex=7050.0(8)E_x = 7050.0(8) keV. Isospin mixing in 31^{31}S does not by itself explain the IMME breakdown in the lowest quartet, but it likely points to similar isospin mixing in the mirror nucleus 31^{31}P, which would result in a perturbation of the 31^{31}P IAS energy. USDB and USDE calculations both predict candidate 31^{31}P states responsible for the mixing in the energy region slightly above Ex=6400E_x = 6400 keV. The second quartet has been completed thanks to the identification of the second 31^{31}S T=3/2T = 3/2 state, and the IMME is validated in this quartet

    Nonuniversal scaling behavior of Barkhausen noise

    Full text link
    We simulate Barkhausen avalanches on fractal clusters in a two-dimensional diluted Ising ferromagnet with an effective Gaussian random field. We vary the concentration of defect sites cc and find a scaling region for moderate disorder, where the distribution of avalanche sizes has the form D(s,c,L)=s(1+τ(c))D(sLDs(c))D(s,c,L) = s^{-(1+\tau (c))}{\cal{D}}(sL^{-D_s(c)}). The exponents τ(c)\tau (c) for size and α(c)\alpha (c) for length distribution, and the fractal dimension of avalanches Ds(c)D_s(c) satisfy the scaling relation Ds(c)τ(c)=α(c)D_s(c)\tau (c) =\alpha (c). For fixed disorder the exponents vary with driving rate in agreement with experiments on amorphous Si-Fe alloys.Comment: 5 pages, Latex, 4 PostScript figures include

    Applied Interventions in the Prevention and Treatment of Obesity Through the Research of Professor Jane Wardle

    Get PDF
    Purpose of Review Obesity presents a challenge for practitioners, policy makers, researchers and for those with obesity themselves. This review focuses on psychological approaches to its management and prevention in children and adults. Recent Findings Through exploring the work of the late Professor Jane Wardle, we look at the earliest behavioural treatment approaches and how psychological theory has been used to develop more contemporary approaches, for example incorporating genetic feedback and habit formation theory into interventions. We also explore how Jane has challenged thinking about the causal pathways of obesity in relation to eating behaviour. Beyond academic work, Jane was an advocate of developing interventions which had real-world applications. Summary Therefore, we discuss how she not only developed new interventions but also made these widely available and the charity that she established
    corecore