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BACKGROUND/OBJECTIVES: Neuropeptide Y (NpY) is an important factor in neuropeptide signalling, and significantly change in the blood and cerebrospinal fluid (CSF) during chronic kidney disease (CKD) progression. However, the role of NpY remains unclear. We aimed to investigate the associations between NpY levels, nutritional status and cardiovascular disease (CVD) in patients with CKD. SUBJECTS/METHODS: In this cohort study, we performed Pearson's correlation analysis and multiple linear regressions to assess the relationship between CSF and serum NpY levels, as well as nutritional indices. Receiver operating characteristic curves were used to evaluate the sensitivity and specificity of CSF NpY levels. As NpY affects the cardiovascular system, Kaplan- Meier analysis was used to investigate the relationship between serum NpY levels and CVD. RESULTS: CSF NpY levels and nutritional indices were related during CKD progression (energy intake: β = 0.236, P < 0.001; mid-arm muscle circumference: β = 0.953, P = 0.014; prealbumin: β = 0.067, P < 0.001), and had high specificity (79.9%). High serum NpY levels may be a risk factor associated with CVD (relative risk =1.8015, 95% confidence interval: 1.0509-3.0881). CONCLUSIONS: Our results suggested a relationship between CSF NpY levels and nutritional indices in CKD patients. High serum NpY concentrations may be a risk factor associated with CVD. European Journal of Clinical Nutrition (2015) 69, 717-721; doi: 10.1038/ejcn.2015.67; published online 29 April 2015, INTRODUCTION Patients with chronic kidney disease (CKD), especially those with end-stage renal disease, suffer from cachexia, potentially along with protein energy wasting (PEW). (1) Nutritional status is both affected by [...]

We present accurate calculations and tabulations of the volume and midplane-averaged complex ac susceptibilities of nonmagnetic conducting cylinders with aspect ratio ranging from 0.1 to 10 as functions of a dimensionless frequency. We discuss their features in terms of eddy-current demagnetizing effect. We explain their applications in high-sensitivity, low-temperature, and high-field ac susceptometers and contactless conductivity measurements. Index Terms--AC susceptibility, ac susceptometer, conducting cylinder, eddy currents, electromagnetic measurements.

For rectangular prisms of dimensions 2a x 2b x 2c with constant material susceptibility X, we have calculated and tabulated the fluxmetric and magnetometric demagnetizing factors [N.sub.f] and [N.sub.m], defined along the 2c dimension as functions of c/[(ab).sup.1/2] (=1 500), a/b(=1 ~ 256), and X(=0 ~ [10.sup.9]). We introduce an interpolation technique for obtaining [N.sub.f,m] with arbitrary values of c/[(ab).sup.1/2], a/b, and X. Index Terms--Demagnetizing correction, fluxmetric demagnetizing factor, magnetometric demagnetizing factor, magnetic measurements, rectangular prisms.

We calculate magnetization and incremental longitudinal and perpendicular susceptibilities for ferromagnets above remanence as functions of longitudinally applied field, assuming a local uniaxial anisotropy to have certain angular distributions. We give analytical formulas, together with computation results, under a wide range of conditions. For anisotropy uniformly oriented in all directions, the classical derivation of the law of approach to saturation is improved by adding a third term, but the resulting formula is inaccurate for most other conditions even if values of the coefficients of the second and third terms are changed. If the longitudinal field is high, the perpendicular incremental susceptibility at uniformly oriented anisotropy can be well approximated by the ratio of spontaneous magnetization to this field, which is the ideal result obtained for zero anisotropy, but a huge departure from this value can be encountered at low fields under certain conditions. Thus, the measurements of perpendicular incremental susceptibility as a function of longitudinal field can be a sensitive probe to the anisotropy and its distribution in ferromagnetic wires. Index Terms--Amorphous wires, circular susceptibility, incremental susceptibility, law of approach to saturation, uniaxial anisotropy.

This paper presents an evaluation and tabulation, as a function of c/a and the normalized frequency [[theta].sup.2] = [a.sup.2][sigma][[micro].sub.dc][omega] of the circular permeability [micro] = [micro]' - j[micro]' defined from its impedance at circular frequency [omega] and normalized to the dc circular permeability [[micro].sub.dc]. The results apply to a ferromagnetic cylinder of diameter 2a and conductivity [sigma] with bamboo domains of sizes 2c. Index Terms--Circular permeability, domain effects, eddy currents, impedance, wires.

In order to study the impedance of long solenoids, a tube model has traditionally been used. The model resistance is expressed in terms of the Bessel functions. We show how to relate the model resistance to the resistance of the actual solenoid, so that the model can be better used in practice. Since the computation accuracy when using the Bessel functions may decrease quickly with increasing the magnitude of their argument, the model results can be calculated only for thin solenoids at low frequencies. This problem has traditionally been solved by using the asymptotic expressions of Bessel functions. We show the appreciable error owing to this and propose a simple approach to make a very accurate correction. Practical formulas for the ac inductance of solenoids are also given. Index Terms - Eddy currents, impedance, resistance, solenoids.

A systematic description of theoretical eddy-current permeability spectra of infinitely long and wide slabs with 180 [degrees] bar domains is made for the classical model, the Pry-Bean and Polivanov model concerning the eddy-current anomaly owing to domain wall displacements (DWD), as well as a model dealing with the anomalous low-frequency eddy-current losses owing to domain magnetization rotations (DMR). A general case including both DWD and DMR is treated based on these models. Analytic formulas are given accompanied by numerical computations. The model results can be directly used in many practical cases. They also provide much information on the nature of eddy-current losses. To explain these, extensive discussions are made, in which concepts such as the equivalent circuit, the classical, localized, and lateral eddy currents, the separate and superimposed eddy currents, and the skin effect are clarified. Index Terms - Eddy currents, losses, magnetic domains, permeability, skin effect, soft magnetic materials/devices.

The most outstanding property of amorphous wires is their capability to be largely magnetized through a single Barkhausen jump giving rise tosquared hysteresis loop. This phenomenon is spontaneously shown in large magnetostriction wires in the as-quenched state. According to the previous model, such a Barkhausen Jump arises from the magnetization reversal inside a core having axial easy magnetization axis. In this work, we review some recent results leading to a refinement of the previous model paying particular attention to the domain structure close to the ends of wires having different lengths. The existence of 'closure' domains in such regions and their variation when applied fields up to a critical value for magnetization reversal is of primary importance for understanding the reversal process. To deepen the knowledge of the dynamics of the wall responsible for the magnetization reversal two experimental studies were performed namely, the conventional Sixtus-Tonks experiment and the magnetization reversal under homogeneous applied field along the sample. The main conclusions are: a) the reversal process is spontaneously initiated close to the end of the wire where the wall is depinned and propagates along the entire wire, b) the starting end alternates in each reversal or remains the same depending on an additional external applied field, and c) the wall during the reversal approaches a planar shape.

Sixtus-Tonks experiment for an amorphous Fe77.5Si7.5B15 wire made by quenching in rotating water has been performed under a tensile stress [Sigma]. The data are analyzed using the formula V[subscript w] = S(H - H[subscript 0]), where V[subscript w] is the axial wall velocity, H is the steady field, and S and H[subscript 0] are constants. To study the wall shape and damping mechanism, tubular- and planar-wall eddy-current models are proposed, and complete sets of formulas are given, including the wall shape, the pulse waveform, and the damping coefficient. A comparison between the experiments and the model prediction indicates that the propagating wall in such amorphous wires is not conical as usually suggested, but close to planar. The damping is dominated by eddy currents at small [Sigma], but with increasing [Sigma] to 915 MPa spin relaxation plays an equally important role.

In this work, the general features concerning the bistable magnetic behaviour of amorphous wires are first introduced. Then, some new results related with the switching mechanism and the involved domain wall propagation are presented which allow us to get deeper knowledge of the actual magnetization reversal process. Based on these new findings, some applications are envisaged. In particular the following applications are described: magnetoelastic sensors using the Matteucci and the inverse Wiedemann effects, size reduced pulse generators and magnetic switches using bent magnetostrictive amorphous wires, encoders with non-magnetostrictive amorphous wires as sensing elements and magnetic field detectors.

An extended critical state model fits data obtained from saturation magnetization curves of a sintered Bi2Sr2CaCu2O superconductor yielding the lower critical and first vortex entry fields, Hc1 and H1, respectively. Hc1 varies linearly and inversely with temperature at 50 Kelvin, and is less than H1. The surface barriers disappear above 50 Kelvin, and irregularities in the magnetization curves render the critical state model invalid.

Stress-current annealing performed on [Fe.sub.73.5][Cu.sub.1][Nb.sub.3][Si.sub.13.5][B.sub.9] amorphous wire results in ultra-soft 'nanocrystalline' wire with an additional very homogeneous transverse magnetic anisotropy. The giant magnetoimpedance (GMI) response of this treated wire has been investigated in a range of ac current ([I.sub.ac] = 0.2 to 20 mA) and frequency (f = 0.01 to I MHz). A maximum GMI ratio as high as around 150% is reported. The magnetoelastic behavior and in particular the influence of applied tensile and torsional stresses, has been analyzed in connection with GMI. From the applied stress dependence of the static field [H.sub.m] at which the maximum impedance is observed, the values of induced anisotropy field ([H.sub.ind] = 3.46 and 3.14 kA/m) and magnetostriction ([[lambdal].sub.s] = 1.42 and 1.59 x [10.sup.-6]) are determined. Index Terms--Giant magnetoimpedance (GMI), induced transverse magnetic anisotropy, nanocrystalline wire, stress-current annealing.

A study was conducted to analyze the magnetoresistance in glass-coated soft magnetic Fe-Ni-Cu microwires. The microwires were prepared using Taylor's technique. Experimental results indicated that negative magnetoresistance reached 8.15% at 77 K and 6.35% at 300 K in a magnetic field of 9.0 T. Findings also showed that magnetoresistance decreases upon annealing the sample at 500 degrees C.