The self-reference effect in memory is the advantage for information encoded about self, relative to other people. The early development of this effect was explored here using a concrete encoding paradigm. Trials comprised presentation of a self- or other-image paired with a concrete object. In Study 1, 4- to 6-year-old children (N = 53) were asked in each trial whether the child pictured would like the object. Recognition memory showed an advantage for self-paired objects. Study 2 (N = 55) replicated this finding in source memory. In Study 3 (N = 56), participants simply indicated object location. Again, recognition and source memory showed an advantage for self-paired items. These findings are discussed with reference to mechanisms that ensure information of potential self-relevance is reliably encoded.
This paper seeks a clearer understanding of the role of water in hydrated polymers. Pulsed NMR relaxation data for the hydrated copolymer poly(N-vinyl-2-pyrrolidone/methyl methacrylate), P-(NVP/MMA), reveal that a significant part of the water is nonfreezable or bound in the sense that it becomes mobile, much like a glass, at -170 K. Consideration of T2 component intensities allows one to estimate the relative fractions of three distinguishably different types of water in P(NVP/MMA). The bound water can be resolved into a mobile component characterized by a long T2 (type A) and a component of lower mobility that combines with plasticized polymer to form an intermediate T2 (type B). In samples with water content in excess of 276 w t % there is also bulklike water that freezes in the vicinity of 273 K. Parallel DSC measurements predict a lower estimate for the amount of nonfreezable water which correlates rather well with the amount of type A water present. Intercomparison of NMR and DSC data is facilitated by a scheme that envisages five thermal equilibrium states in hydrated P(NVP/MMA). This study highlights the importance of taking the plasticized polymer contribution into account in estimating bound water by the NMR technique. IntroductionThe burgeoning literature on the role of water in natural and synthetic polymers attests to the scientific and commercial importance of these ~ystems.l-~ Substantial progress has been made in unraveling the inherent complexities of water/polymer interactions, with most attention focused upon water in natural polymers, particularly proteins and polypeptides, and in those synthetic polymers such as poly(Zhydroxyethy1 methacrylate) (PHEMA) that
n-of-1 studies test hypotheses within individuals based on repeated measurement of variables within the individual over time. Intra-individual effects may differ from those found in between-participant studies. Using examples from a systematic review of n-of-1 studies in health behaviour research, this article provides a state of the art overview of the use of n-of-1 methods, organised according to key methodological considerations related to n-of-1 design and analysis, and describes future challenges and opportunities. A comprehensive search strategy (PROSPERO:CRD42014007258) was used to identify articles published between 2000 and 2016, reporting observational or interventional n-of-1 studies with health behaviour outcomes. Thirty-nine articles were identified which reported on n-of-1 observational designs and a range of n-of-1 interventional designs, including AB, ABA, ABABA, alternating treatments, n-of-1 randomised controlled trial, multiple baseline and changing criterion designs. Behaviours measured included treatment adherence, physical activity, drug/alcohol use, sleep, smoking and eating behaviour. Descriptive, visual or statistical analyses were used. We identify scope and opportunities for using n-of-1 methods to answer key questions in health behaviour research. n-of-1 methods provide the tools needed to help advance theoretical knowledge and personalise/tailor health behaviour interventions to individuals.
Collated brcad-line NMR and DSC measurements sensitively probe the behavior of water in hydrated poly(hydroxyethy1 methacrylate) (PHEMA). NMR reveals that bound water becomes mobile at -180 K in keeping with observations in many other hydrated polymers; DSC is insensitive to events at these temperatures. In samples with a high water content, a fraction of this mobile water subsequently freezes between 230 and 260 K. The amount of freezable and nonfreezable water in hydrated PHEMA is determined quantitatively. Preliminary cross-relaxation experiments at 253 and 293 K indicate that NMR spin-lattice relaxation rates for water will be overestimated if the effects of cross-relaxation between the polymer and water proton spin systems are neglected. Although PHEMA is less hydrophilic than poly(N-vinyl-2pyrrolidone/methyl methacrylate), studied in part 1, the relative fraction of bound water is significantly higher. Hysteresis effects in hydrated PHEMA are investigated in some detail.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.