Molecular-dynamics simulations of the dynamical excitations in commensurate submonolayer films of nitrogen molecules on graphite

URL:http://link.aps.org/doi/10.1103/PhysRevB.54.14077 DOI:10.1103/PhysRevB.54.14077The dynamics of commensurate submonolayer solids of N2 molecules adsorbed on the basal planes of graphite have been studied using molecular-dynamics simulations. The calculations yielded the temperature dependence of the Brillouin-zone-center gap in the acoustic-phonon branches, for comparison with inelastic neutron-scattering experiments on the submonolayer solid. The calculated frequency gap was the same in submonolayer and monolayer films at low temperatures. At intermediate temperatures, the diffusive molecular motion associated with the presence of vacancies caused the gap mode to be less clearly defined in the coherent scattering function. Diffusion constants are calculated at submonolayer coverages, and temperatures up to 40 K for a population of molecules identified as mobile.This work was partially supported by the National Science Foundation under Grant No. DMR-9314235 (H.T.) and Nos. DMR-9120199 and DMR-9423307 (L.W.B.) and by The Danish Natural Science Foundation (F.Y.H.). L.W.B. thanks the Fysisk-Kemisk Institut and the Technical University of Denmark for hospitality during the period this work was completed

An evaluation of UV protection imparted by cotton fabrics dyed with natural colorants

BACKGROUND: The ultraviolet properties of textiles dyed with synthetic dyes have been widely reported in literature. However, no study has investigated the ultraviolet properties of natural fabrics dyed with natural colorants. This study reports the Ultraviolet Protection Factor (UPF) of cotton fabrics dyed with colorants of plant and insect origins. METHODS: Three cotton fabrics were dyed with three natural colorants. Fabrics were characterized with respect to fabric construction, weight, thickness and thread count. Influence of fabric characteristics on Ultraviolet Protection Factor was studied. Role of colorant concentration on the ultraviolet protection factor was examined via color strength analysis. RESULTS: A positive correlation was observed between the weight of the fabric and their UPF values. Similarly, thicker fabrics offered more protection from ultraviolet rays. Thread count appears to negatively correlate with UPF. Dyeing with natural colorants dramatically increased the protective abilities of all three fabric constructions. Additionally, within the same fabric type UPF values increased with higher depths of shade. CONCLUSION: Dyeing cotton fabrics with natural colorants increases the ultraviolet protective abilities of the fabrics and can be considered as an effective protection against ultraviolet rays. The UPF is further enhanced with colorant of dark hues and with high concentration of the colorant in the fabric

What happens for informal caregivers during transition to increased levels of care for the person with dementia? A systematic review protocol

Abstract Background Dementia is a globally prevalent disease that requires ongoing and increasing levels of care, often provided in the first instance by informal caregivers. Supporting transitions in informal caregiving in dementia is a pertinent issue for caregivers, care providers and governments. There is no existing systematic review that seeks to identify and map the body of literature regarding the review question: ‘What happens for informal caregivers during transition to increased levels of care for the person with dementia?’ Methods/design ASSIA, CINAHL+, MEDLINE, PsycINFO, SCIE, Social Service Abstracts and Web of Science will be systematically searched. Specialist dementia research libraries will be contacted. Reviews identified as relevant during the search process, their reference lists, and reference lists of accepted papers will be hand-searched. Qualitative, quantitative and mixed methods studies that seek to represent the experiences of, or examine the impact upon, informal caregivers during transition to increased formal care for the person with dementia will be eligible for inclusion. Synthesis will be segregated into qualitative and quantitative papers. Findings will be summarised, and the review will be prepared for publication. Discussion The review will seek to identify potentially vulnerable groups in need of support and as such, inform the practice of those offering support. It will also inform future research by highlighting areas in which current literature is insubstantial. Systematic review registration PROSPERO CRD4201706724

The influence of institutional discourses on the work of informal carers: an institutional ethnography from the perspective of informal carers

Abstract Background The growing numbers of seniors worldwide and the need for support and services that follow from a higher standard of living have led to an increased focus on scarce benefits and limited human resources. At the same time, many western countries have had to make welfare cuts to balance budgets. This has brought the contributions of informal carers to the fore. Thus far, the focus has generally been on the need for the informal carers to receive information and support; to enable them to contribute. Methods The study is designed as an institutional ethnography. The article describes the social processes of informal caregiving and how it interacts with formal caregiving, from the perspective of informal carers. The research question for the study is How do institutional discourses on the work of informal carers influence informal carework? Data for the article comes from qualitative semi-structured interviews with 26 informal carers caring for persons with dementia in Norway, and with 7 administrators working in the allocation divisions of five different municipalities. Results The results demonstrate how three institutional discourses of informal carers’ work influence the allocation divisions’ practices and the work of informal carers in caring for their next of kin. The three discourses are categorised as moral and family obligation, shared care and task specificity. The informal carers want to contribute, as they feel a family and moral obligation to their next of kin. In the interaction with the allocation division, they find that the expectation that they will share in the carework and perform specific tasks forces them to perform care within a framework set by the public services. Conclusions The findings suggest that further research should challenge how services are distributed and allocated rather than focus on how to enable informal carers to fulfil their role better. Because of their moral and family obligation, the informal carers do not have to be forced to perform certain tasks or parts of the shared care. To maintain the informal carers’ carework and to fully utilise their contributions, public services would benefit from collaborating with the informal carers to fulfil the total care need of the person with dementia

A qualitative study of professional and client perspectives on information flows and decision aid use

<p>Abstract</p> <p>Background</p> <p>This paper explores the meanings given by a diverse range of stakeholders to a decision aid aimed at helping carers of people in early to moderate stages of dementia (PWD) to select community based respite services. Decision aids aim to empower clients to share decision making with health professionals. However, the match between health professionals' perspectives on decision support needs and their clients' perspective is an important and often unstudied aspect of decision aid use.</p> <p>Methods</p> <p>A secondary analysis was undertaken of qualitative data collected as part of a larger study. The data included twelve interviews with carers of people with dementia, three interviews with expert advisors, and three focus groups with health professionals. A theoretical analysis was conducted, drawing on theories of 'positioning' and professional identity.</p> <p>Results</p> <p>Health professionals are seen to hold varying attitudes and beliefs about carers' decision support needs, and these appeared to be grounded in the professional identity of each group. These attitudes and beliefs shaped their attitudes towards decision aids, the information they believed should be offered to dementia carers, and the timing of its offering. Some groups understood carers as needing to be protected from realistic information and consequently saw a need to filter information to carer clients.</p> <p>Conclusion</p> <p>Health professionals' beliefs may cause them to restrict information flows, which can limit carers' ability to make decisions, and limit health services' ability to improve partnering and shared decision making. In an era where information is freely available to those with the resources to access it, we question whether health professionals should filter information.</p

Decision aids for respite service choices by carers of people with dementia: development and pilot RCT

<p>Abstract</p> <p>Background</p> <p>Decision aids are often used to assist individuals confronted with a diagnosis of a serious illness to make decisions about treatment options. However, they are rarely utilised to help those with chronic or age related conditions to make decisions about care services. Decision aids should also be useful for carers of people with decreased decisional capacity. These carers' choices must balance health outcomes for themselves and for salient others with relational and value-based concerns, while relying on information from health professionals. This paper reports on a study that both developed and pilot tested a decision aid aimed at assisting carers to make evaluative judgements of community services, particularly respite care.</p> <p>Methods</p> <p>A mixed method sequential study, involving qualitative development and a pilot randomised controlled trial, was conducted in Tasmania, Australia. We undertook 13 semi-structured interviews and three focus groups to inform the development of the decision aid. For the randomised control trial we randomly assigned 31 carers of people with dementia to either receive the service decision aid at the start or end of the study. The primary outcome was measured by comparing the difference in carer burden between the two groups three months after the intervention group received the decision aid. Pilot data was collected from carers using interviewer-administered questionnaires at the commencement of the project, two weeks and 12 weeks later.</p> <p>Results</p> <p>The qualitative data strongly suggest that the intervention provides carers with needed decision support. Most carers felt that the decision aid was useful. The trial data demonstrated that, using the mean change between baseline and three month follow-up, the intervention group had less increase in burden, a decrease in decisional conflict and increased knowledge compared to control group participants.</p> <p>Conclusions</p> <p>While these results must be interpreted with caution due to the small sample size, all intervention results trend in a direction that is beneficial for carers and their decisional ability. Mixed method data suggest the decision aid provides decisional support that carers do not otherwise receive. Decision aids may prove useful in a community health services context.</p> <p>Trial registration number</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN32163031">ISRCTN32163031</a></p