16,563 research outputs found

    Misreporting of energy and micronutrient intake estimated by food records and 24 hour recalls, control and adjustment methods in practice

    Get PDF
    In order to assess nutritional adequacy, valid estimates of nutrient intake are required. One of the main errors in dietary assessment is misreporting. The objective was to review the extent, nature and determinants of misreporting in dietary assessment, how this affects reported intakes of micronutrients and how this is identified and measured, and to identify the best ways of dealing with misreporting when interpreting results. A systematic literature search was conducted for studies of misreporting of dietary intake in adults by 24 hour recalls or by estimated or weighed food records, published up to March 2008. Thirty-seven relevant studies were identified. Possible causes of misreporting were identified. Methods most used to identify misreporting were the Goldberg cut-off (46 % studies) and the doubly labelled water technique (24 % studies). The magnitude of misreporting of energy intake was similar in all three dietary assessment methods. The percentage of under-reporters was about 30 % and energy intake was underestimated by approximately 15 %. Seven papers presented usable data for micronutrient intake. Absolute intakes of Fe, Ca and vitamin C (the three micronutrients addressed in all papers) were on average 30 % lower in low-energy reporters (LER) than that in non-LER and, although results were not consistent, there was a tendency for micronutrient density to be higher in LER. Excluding underreporters or using energy adjustment methods for micronutrient intakes is discussed. Residual method of energy adjustment seems to be a good tool for practice to decrease an influence of misreporting when interpreting results of studies based on food records and 24 hour recall

    Pair Correlations, Short Range Order and Dispersive Excitations in the Quasi-Kagome Quantum Magnet Volborthite

    Get PDF
    We present spatial and dynamic information on the s=1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)2.2D2O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest neighbor pair correlations, with short range order at wave vectors Q1=0.65(3) {\AA}^-1 and Q2=1.15(5) {\AA}^-1 emerging below 5 K. The excitation spectrum, S(Q,{\omega}), reveals two steep branches dispersing from Q1 and Q2, and a flat mode at {\omega}=5.0(2) meV. The results allow us to identify the cross-over at T*=1 K in 51V NMR and specific heat measurements as the build-up of correlations at Q_1. We compare our data to theoretical models proposed for volborthite, and demonstrate that the excitation spectrum can be explained by spin-wave-like excitations with anisotropic exchange parameters, as also suggested by recent local density calculations.Comment: Rewritten article resubmitted to Phys. Rev. Lett. 021

    Scaling of polymers in aligned rods

    Full text link
    We study the behavior of self avoiding polymers in a background of vertically aligned rods that are either frozen into random positions or free to move horizontally. We find that in both cases the polymer chains are highly elongated, with vertical and horizontal size exponents that differ by a factor of 3. Though these results are different than previous predictions, our results are confirmed by detailed computer simulations.Comment: 4 pages, 4 figure

    Evidence for precession of the isolated neutron star RX J0720.4-3125

    Full text link
    The XMM-Newton spectra of the isolated neutron star RX J0720.4-3125 obtained over 4.5 years can be described by sinusoidal variations in the inferred blackbody temperature, the size of the emitting area and the depth of the absorption line with a period of 7.1 +/- 0.5 years, which we suggest to be the precession period of the neutron star. Precession of a neutron star with two hot spots of different temperature and size, probably not located exactly in antipodal positions, may account for the variations in the X-ray spectra, changes in the pulsed fraction, shape of the light curve and the phase-lag between soft and hard energy bands observed from RX J0720.4-3125. An independent sinusoidal fit to published and new pulse timing residuals from a coherent analysis covering ~12 years yields a consistent period of 7.7 +/- 0.6 years supporting the precession model.Comment: Accepted for publication in A&A Letters, 5 pages, 5 figure

    Theory of interlayer exchange interactions in magnetic multilayers

    Full text link
    This paper presents a review of the phenomenon of interlayer exchange coupling in magnetic multilayers. The emphasis is put on a pedagogical presentation of the mechanism of the phenomenon, which has been successfully explained in terms of a spin-dependent quantum confinement effect. The theoretical predictions are discussed in connection with corresponding experimental investigations.Comment: 18 pages, 4 PS figures, LaTeX with IOP package; v2: ref. added. Further (p)reprints available from http://www.mpi-halle.de/~theory

    Prescribing patterns, adherence and LDL-cholesterol response of type 2 diabetes patients initiating statin on low-dose versus standard-dose treatment:a descriptive study

    Get PDF
    AimsThe aim of this study was to describe and compare treatment modifications and discontinuation, adherence levels and response to treatment in patients with type 2 diabetes initiating on low-dose vs. standard-dose statin treatment.MethodsA 2-year follow-up cohort study was performed using data from the Groningen Initiative to Analyse Type 2 Diabetes Treatment (GIANTT) database in patients with type 2 diabetes initiating statin treatment between January 2007 and December 2012. First, we determined whether there were differences in treatment modifications and discontinuation after statin initiation between patients starting on a low-dose vs. standard-dose. Second, we looked at differences in adherence and LDL-cholesterol response after 2 years follow-up between these groups.ResultsAround 22% of patients initiated statin treatment on a dose lower than recommended. More than half of them remained on a low dose during a 2-year follow-up period, whereas less than 15% received a dose increase. Of the patients initiating on standard-dose, also more than half remained on the same treatment during this period, whereas 8% received a dose decrease without subsequent increase. Over 25% of patients starting on low-dose or standard-dose treatment discontinued treatment, often within the first 180 days after initiation or after a first treatment change. Patients on low-dose treatment had lower adherence levels and were less likely to have adequate LDL-cholesterol response compared with patients on standard-dose after 2 years follow-up.ConclusionsCurrent patterns of statin treatment in patients with type 2 diabetes are suboptimal, with discontinuation, inadequate adherence levels and lack of treatment intensification seen in those who had inadequate LDL-cholesterol response after 2 years of follow-up. Patients starting on low-dose had more treatment modifications, discontinuation and adherence problems as compared with those starting on standard-dose treatment, which calls for a closer look at the rationale of starting patients on low-dose statin treatment.</p

    Historical urban growth in Europe (1300–1800)

    Get PDF
    This paper analyses the evolution of the European urban system from a long-term perspective (from 1300 to 1800). Using the method recently proposed by Clauset, Shalizi, and Newman, a Pareto-type city size distribution (power law) is rejected from 1300 to 1600. A power law is a plausible model for the city size distribution only in 1700 and 1800, although the log-normal distribution is another plausible alternative model that we cannot reject. Moreover, the random growth of cities is rejected using parametric and non-parametric methods. The results reveal a clear pattern of convergent growth in all the periods
    • …
    corecore