Atomic size oscillations in conductance histograms for gold nanowires and the influence of work hardening

Nanowires of different nature have been shown to self-assemble as a function of stress at the contact between two macroscopic metallic leads. Here we demonstrate for gold wires that the balance between various metastable nanowire configurations is influenced by the microstructure of the starting materials and we discover a new set of periodic structures, which we interpret as due to the atomic discreteness of the contact size for the three principal crystal orientations.Comment: This version corrects an error in attributing the three observed periods, and includes a comparison with recent model calculation

Conductance of Pd-H nanojunctions

Results of an experimental study of palladium nanojunctions in hydrogen environment are presented. Two new hydrogen-related atomic configurations are found, which have a conductances of ~0.5 and ~1 quantum unit (2e^2/h). Phonon spectrum measurements demonstrate that these configurations are situated between electrodes containing dissolved hydrogen. The crucial differences compared to the previously studied Pt-H_2 junctions, and the possible microscopic realizations of the new configurations in palladium-hydrogen atomic-sized contacts are discussed.Comment: 4 pages, 4 figure

Changes in health-related quality of life in older patients with acute myocardial infarction or congestive heart failure: a prospective study

OBJECTIVES: To study changes in health-related quality of life (HR-QL) following acute myocardial infarction (AMI) or congestive heart failure (CHF) in older people (greater than or equal to 57 yr).DESIGN: Prospective cohort Study.SETTING: Primary healthcare registers.PARTICIPANTS: Patients were enrolled on the basis of primary healthcare records. Eighty-nine AMI patients (mean age = 69.5) and 119 CHF patients (mean age = 74.5) were included for analysis.MEASUREMENTS: HR-QL was conceptualized and measured by means of physical (activities of daily living (ADL), instrumental activities of daily living (IADL)), psychological (depressive symptoms, anxiety), social, and role functioning. Premorbid data (TO) were available from a 1993 community-based survey. Incident AMI and CHF cases, developed after 1993, were prospectively followed for 12 months. Assessments were performed at 6 weeks (T1) and 6 (T2) and 12 months (T3) after diagnosis.RESULTS: At the premorbid assessment, AMI patients did not significantly differ on HR-QL from a reference group of older people, whereas CHF patients were on average older and had worse HR-QL compared to the reference group. Although CHF had not yet been diagnosed at TO, symptoms were already present and resulted in decreased levels of functioning. At T1, all HR-QL measures showed worse functioning compared with TO, except for depressive symptoms that presented later (at T2). In contrast to the delay in depressive symptoms, a significant increase in anxiety was already seen at T1. The effect of the somatic conditions was the largest on physical functioning. Effects on psychological and social functioning were less pronounced but still significant. Effects were maintained during the 12 months of follow-up.CONCLUSION: The negative consequences on HR-QL in both AMI and CHF patients are not temporary. No recovery of function was seen in AMI patients, and functioning and CHF patients continued to decline in the first year after diagnosis

Keijsers, Shklyarevskii and van Kempen Reply

Answer to the Comment on ``Point-Contact Study of Fast and Slow Two-Level Fluctuators in Metallic Glasses'' by Jan von Delft et al.Comment: 3 pages, no figures, accepted Phys. Rev. Letter

Socioeconomic Status and the Course of Quality of Life in Older Patients with Coronary Heart Disease

BACKGROUND: Previous research suggests that socioeconomic status (SES) might be related to the course of quality of life (QoL) in coronary heart disease (CHD) patients. The authors sought to determine whether there are differences in the course of QoL before and after the incidence of CHD among older persons of differing SES. METHOD: Two hundred two CHD patients were followed up longitudinally using a community-based survey. Data on patients' QoL were collected before the diagnosis and at three follow-up assessments. RESULTS: High SES patients reported better outcomes at the premorbid assessment with fewer depressive feelings and better physical functioning. In physical functioning, similar results were repeated 6 and 12 months after the diagnosis. Additionally, high SES patients showed better role and social functioning 1 year after CHD. A multivariate analysis of variance revealed differential longitudinal pathways in relation to SES in role, social, and physical functioning. CONCLUSION: CHD modulates premorbid differences in depressive feelings. Conversely, high SES leads to better outcomes in all functional domains in the long-term after diagnosis. Postmorbid differences in physical functioning are not directly related to CHD, but rather the reestablishment of a premorbid situation. In contrast, socioeconomic inequalities in social and role functioning are a direct response to the impact of the disease

Psychosociale aspecten van gezondheid en zelfredzaamheid bij ouderen: van determinanten naar interventie

Een centrale vraag binnen de sociale gerontologie betreft hoe het is te verklaren dat sommige ouderen tot op hoge leeftijd – ongeacht de aanwezigheid van ziekte – op een redelijk niveau blijven functioneren, terwijl dit voor andere ouderen niet het geval is. Dit artikel schetst een conceptueel model dat inzicht geeft in de individuele uitwerking van (voornamelijk) chronische gezondheidsproblemen en daardoor aanknopingspunten biedt voor gerichte interventies voor het bevorderen van zelfredzaamheid bij ouderen. Meer specifiek wordt ingegaan op de rol die gevoelens van competentie en controle hierbij spelen. Uit het beschreven onderzoek blijkt dat gevoelens van competentie en controle weliswaar niet overheersend maar wel consistent in positieve zin bijdragen aan zelfredzaamheid en het functioneren van ouderen. Daarmee is een basis gelegd voor de ontwikkeling en evaluatie van psychosociale interventies die beide concepten en zelfredzaamheid in positieve zin kunnen beïnvloeden. Twee van dergelijke interventies worden gepresenteerd: vermindering van angst om te vallen en zelfmanagement bij chronisch hartfalen. Geconcludeerd wordt dat de ontwikkeling en de bewijskracht van dergelijke interventies pas in de kinderschoenen staan maar potentie hebben. Een verdere stimulans ervan kan bijdragen aan een meer adequate ouderenzorg omdat deze aansluit bij ouderen zelf en mogelijk de zorgvraag zal verminderen

Opfok, een zaak van opfokker én leghennenhouder

Leghennenhouder willen dat de overgang van de opfokstal naar de legstal zo vlot mogelijk verloopt. Een bezoek aan de opfokker kan zeker bij helpen bij een goede voorbereiding. Dit BioKennisbericht gaat in op de volgende vragen: wat kun je vragen aan de opfokker? Wat kun je met deze infomatie op je eigen bedrijf doen? Hoe begeleid je optimaal een opfokhen naar leghen

Neurobehavioral effects of transportation noise in primary schoolchildren: a cross-sectional study.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.BACKGROUND: Due to shortcomings in the design, no source-specific exposure-effect relations are as yet available describing the effects of noise on children's cognitive performance. This paper reports on a study investigating the effects of aircraft and road traffic noise exposure on the cognitive performance of primary schoolchildren in both the home and the school setting. METHODS: Participants were 553 children (age 9-11 years) attending 24 primary schools around Schiphol Amsterdam Airport. Cognitive performance was measured by the Neurobehavioral Evaluation System (NES), and a set of paper-and-pencil tests. Multilevel regression analyses were applied to estimate the association between noise exposure and cognitive performance, accounting for demographic and school related confounders. RESULTS: Effects of school noise exposure were observed in the more difficult parts of the Switching Attention Test (SAT): children attending schools with higher road or aircraft noise levels made significantly more errors. The correlational pattern and factor structure of the data indicate that the coherence between the neurobehavioral tests and paper-and-pencil tests is high. CONCLUSIONS: Based on this study and previous scientific literature it can be concluded that performance on simple tasks is less susceptible to the effects of noise than performance on more complex tasks.Funding was provided by the European Community (QLRT-2000-00197), the Department of Environment, Food and Rural Affairs in the UK, the Dutch Ministry of Spatial Planning, Housing and the Environment, the Dutch Ministry of Public Health, Welfare and Sports, and the Dutch Ministry of Transport, Public Works and Water Management