970 research outputs found
Measurement of the adhesion between single melamine-formaldehyde resin microparticles and a flat fabric surface using AFM
An understanding of the adhesion of microparticles, particularly microcapsules, containing a functional component to a fabric surface is crucial to an effective application of this component to the fibre. Fabric surface is very rough; hence, direct measurement of the adhesion of single microparticles to surfaces with a roughness greater than the particle diameter is difficult. In the study reported here, cotton films were generated by dissolving cotton powder in an organic solvent and their properties including surface roughness, thickness, contact angle and purity were characterised. The adhesive forces between single melamineformaldehyde (MF) resin microparticles and a cotton film under ambient conditions with a relative humidity of above 40% were measured using atomic force microscopy; they are considered to be dominated by capillary forces. It was found that there was little adhesion between a MF microparticle and a cotton film in an aqueous solution of sodium dodecylbenzene sulphonate as surfactant. Repulsion between them was observed, but it reduced with increase in the surfactant concentration and decrease in the pH of the solution. The repulsion contributions are thought to originate mainly from electrostatic repulsion. It is believed that the studies on the adhesion between single MF microparticles and a cotton film under ambient conditions or dispersed in surfactant solutions, are beneficial to the attempts to enhance the adhesion of microcapsules to fabric surfaces via a modification of their surface composition and morphology
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Postnatal health and care following hypertensive disorders in pregnancy: a prospective cohort study (BPiPP study).
INTRODUCTION: One in 10 women have hypertensive disorders in pregnancy (HDP) and are at risk of adverse short- and long-term health outcomes, yet there is limited information on their postnatal health and care needs. This study aimed to look at postnatal physical and psychological morbidity in women with HDP, compared to women without HDP, and the postnatal care received in both groups. METHODS: Within a prospective cohort study, women with and without HDP were identified and recruited on the postnatal ward of 17 maternity units across England and invited to complete a short baseline questionnaire. At 3 months postpartum, women were sent a follow-up questionnaire, with reminders. The principal outcomes were the mean score at 3 months for the Edinburgh Postnatal Depression Scale (EPDS) and the EuroQol Group 5-dimension (EQ-5D) scale. RESULTS: One thousand eight hundred twenty-nine women agreed to participate. Of these, 1757 (96%) completed the baseline questionnaire: 769 (44%) women had HDP and 988 (56%) women did not. Despite a difference in health-related quality of life and symptoms of depression at baseline between the two groups, at 3 months postnatal, within the 653 women who completed their follow-up questionnaire (37.2% of those who completed the baseline questionnaire) there were no significant differences between the groups (median EQ-5D VAS: 85 in women with HDP, 85 in women without HDP, p = 0.99 and mean EPDS score 5.5 in women with HDP, 5.0 in women without HDP, p = 0.80). Overall levels of physical postnatal morbidity were high, with 89% reporting one or more morbidities. Approximately 9% of women were re-admitted within 3 months after birth, higher in the HDP group (13.1%) higher compared to women without HDP (5.5%; RR 2.41; 95% CI 1.44-4.05). CONCLUSION: Overall levels of physical and psychological morbidity were high in this postnatal population. Although there were increased needs of women with HDP in the immediate postnatal period (compared to other women), their health assessments were similar at 3 months. This study highlights the unmet needs of women in the postnatal period, in addition to a missed opportunity to influence future pregnancies and improve the longer-term health of women and their babies
Evidence based post graduate training. A systematic review of reviews based on the WFME quality framework
<p>Abstract</p> <p>Background</p> <p>A framework for high quality in post graduate training has been defined by the World Federation of Medical Education (WFME). The objective of this paper is to perform a systematic review of reviews to find current evidence regarding aspects of quality of post graduate training and to organise the results following the 9 areas of the WFME framework.</p> <p>Methods</p> <p>The systematic literature review was conducted in 2009 in Medline Ovid, EMBASE, ERIC and RDRB databases from 1995 onward. The reviews were selected by two independent researchers and a quality appraisal was based on the SIGN tool.</p> <p>Results</p> <p>31 reviews met inclusion criteria. The majority of the reviews provided information about the training process (WFME area 2), the assessment of trainees (WFME area 3) and the trainees (WFME area 4). One review covered the area 8 'governance and administration'. No review was found in relation to the mission and outcomes, the evaluation of the training process and the continuous renewal (respectively areas 1, 7 and 9 of the WFME framework).</p> <p>Conclusions</p> <p>The majority of the reviews provided information about the training process, the assessment of trainees and the trainees. Indicators used for quality assessment purposes of post graduate training should be based on this evidence but further research is needed for some areas in particular to assess the quality of the training process.</p
Protocol for the saMS trial (supportive adjustment for multiple sclerosis): a randomized controlled trial comparing cognitive behavioral therapy to supportive listening for adjustment to multiple sclerosis
BackgroundMultiple Sclerosis (MS) is an incurable, chronic, potentially progressive and unpredictable disease of the central nervous system. The disease produces a range of unpleasant and debilitating symptoms, which can have a profound impact including disrupting activities of daily living, employment, income, relationships, social and leisure activities, and life goals. Adjusting to the illness is therefore particularly challenging. This trial tests the effectiveness of a cognitive behavioural intervention compared to supportive listening to assist adjustment in the early stages of MS.MethodsThis is a two arm randomized multi-centre parallel group controlled trial. 122 consenting participants who meet eligibility criteria will be randomly allocated to receive either Cognitive Behavioral Therapy or Supportive Listening. Eight one hour sessions of therapy (delivered over a period of 10 weeks) will be delivered by general nurses trained in both treatments. Self-report questionnaire data will be collected at baseline (0 weeks), mid-therapy (week 5 of therapy), post-therapy (15 weeks) and at six months (26 weeks) and twelve months (52 weeks) follow-up. Primary outcomes are distress and MS-related social and role impairment at twelve month follow-up. Analysis will also consider predictors and mechanisms of change during therapy. In-depth interviews to examine participants’ experiences of the interventions will be conducted with a purposively sampled sub-set of the trial participants. An economic analysis will also take place. DiscussionThis trial is distinctive in its aims in that it aids adjustment to MS in a broad sense. It is not a treatment specifically for depression. Use of nurses as therapists makes the interventions potentially viable in terms of being rolled out in the NHS. The trial benefits from incorporating patient input in the development and evaluation stages. The trial will provide important information about the efficacy, cost-effectiveness and acceptability of the interventions as well as mechanisms of psychosocial adjustment.Trial registrationCurrent Controlled Trials ISRCTN91377356<br/
Entrepreneurs’ age, institutions, and social value creation goals: a multi-country study
This study explores the relationship between an entrepreneur's age and his/her social value creation goals. Building on the lifespan developmental psychology literature and institutional theory, we hypothesize a U-shaped relationship between entrepreneurs’ age and their choice to create social value through their ventures, such that younger and older entrepreneurs create more social value with their businesses while middle age entrepreneurs are relatively more economically and less socially oriented with their ventures. We further hypothesize that the quality of a country’s formal institutions in terms of economic, social, and political freedom steepen the U-shaped relationship between entrepreneurs’ age and their choice to pursue social value creation as supportive institutional environments allow entrepreneurs to follow their age-based preferences. We confirm our predictions using multilevel mixed-effects linear regressions on a sample of over 15,000 entrepreneurs (aged between 18 and 64 years) in 45 countries from Global Entrepreneurship Monitor data. The findings are robust to several alternative specifications. Based on our findings, we discuss implications for theory and practice, and we propose future research directions
First Evidence for Adoption in California Sea Lions
Demographic parameters such as birth and death rates determine the persistence of populations. Understanding the mechanisms that influence these rates is essential to developing effective management strategies. Alloparental behavior, or the care of non-filial young, has been documented in many species and has been shown to influence offspring survival. However, the role of alloparental behavior in maintaining population viability has not been previously studied. Here, we provide the first evidence for adoption in California sea lions and show that adoption potentially works to maintain a high survival rate of young and may ultimately contribute to population persistence. Alloparental behavior should have a positive effect on the population growth rate when the sum of the effects on fitness for the alloparent and beneficiary is positive
The use of open data as a material for learning
Open data has potential value as a material for use in learning activities. However, approaches to harnessing this are not well understood or in mainstream use in education. In this research, early adopters from a diverse range of educational projects and teaching settings were interviewed to explore their rationale for using open data in teaching, how suitable activity designs could be achieved, and the practical challenges of using open data. A thematic analysis was conducted to identify patterns and relationships in these open data-based practices that have already emerged. A document analysis of teaching materials and other related artefacts was used to augment and validate the findings. Drawing on this, common approaches and issues are identified, and a conceptual framework to support greater use of open data by educators is described. This paper also highlights where existing concepts in education and educational technology research, including inquiry-based learning, authenticity, motivation, dialogue, and personalisation can help us to understand the value and challenges of using open data in education
A single-electron transistor made from a cadmium selenide nanocrystal
The techniques of colloidal chemistry permit the routine creation of
semiconductor nanocrystals, whose dimensions are much smaller than those that
can be realized using lithographic techniques. The sizes of such nanocrystals
can be varied systematically to study quantum size effects or to make novel
electronic or optical materials with tailored properties. Preliminary studies
of both the electrical and optical properties of individual nanocrystals have
been performed recently. These studies show clearly that a single excess charge
on a nanocrystal can markedly influence its properties. Here we present
measurements of electrical transport in a single-electron transistor made from
a colloidal nanocrystal of cadmium selenide. This device structure enables the
number of charge carriers on the nanocrystal to be tuned directly, and so
permits the measurement of the energy required for adding successive charge
carriers. Such measurements are invaluable in understanding the energy-level
spectra of small electronic systems, as has been shown by similar studies of
lithographically patterned quantum dots and small metallic grains.Comment: 3 pages, PDF forma
Avaliação dos resultados do tratamento cirúrgico da escoliose na atrofia muscular espinhal tipo 2
Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity
Because of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)
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