Improved silicon carbide for advanced heat engines

Work performed to develop silicon carbide materials of high strength and to form components of complex shape and high reliability is described. A beta-SiC powder and binder system was adapted to the injection molding process and procedures and process parameters developed capable of providing a sintered silicon carbide material with improved properties. The initial effort has been to characterize the baseline precursor materials (beta silicon carbide powder and boron and carbon sintering aids), develop mixing and injection molding procedures for fabricating test bars, and characterize the properties of the sintered materials. Parallel studies of various mixing, dewaxing, and sintering procedures have been carried out in order to distinguish process routes for improving material properties. A total of 276 MOR bars of the baseline material have been molded, and 122 bars have been fully processed to a sinter density of approximately 95 percent. The material has a mean MOR room temperature strength of 43.31 ksi (299 MPa), a Weibull characteristic strength of 45.8 ksi (315 MPa), and a Weibull modulus of 8.0. Mean values of the MOR strengths at 1000, 1200, and 14000 C are 41.4, 43.2, and 47.2 ksi, respectively. Strength controlling flaws in this material were found to consist of regions of high porosity and were attributed to agglomerates originating in the initial mixing procedures. The mean stress rupture lift at 1400 C of five samples tested at 172 MPa (25 ksi) stress was 62 hours and at 207 MPa (30 ksi) stress was 14 hours. New fluid mixing techniques have been developed which significantly reduce flaw size and improve the strength of the material. Initial MOR tests indicate the strength of the fluid-mixed material exceeds the baseline property by more than 33 percent

Kidney disease pathways, options and decisions: an environmental scan of international patient decision aids

Background: Conservative management is recognized as an acceptable treatment for people with worsening chronic kidney disease; however, patients consistently report they lack understanding about their changing disease state and feel unsupported in making shared decisions about future treatment. The purpose of this review was to critically evaluate patient decision aids (PtDAs) developed to support patient–professional shared decision-making between dialysis and conservative management treatment pathways. Methods: We performed a systematic review of resources accessible in English using environmental scan methods. Data sources included online databases of research publications, repositories for clinical guidelines, research projects and PtDAs, international PtDA expert lists and reference lists from relevant publications. The resource selection was from 56 screened records; 17 PtDAs were included. A data extraction sheet was applied to all eligible resources, eliciting resource characteristics, decision architecture to boost/bias thinking, indicators of quality such as International Standards for Patient Decision Aids Standards checklist and engagement with health services. Results: PtDAs were developed in five countries; eleven were publically available via the Internet. Treatment options described were dialysis (n = 17), conservative management (n = 9) and transplant (n = 5). Eight resources signposted conservative management as an option rather than an active choice. Ten different labels across 14 resources were used to name ‘conservative management’. The readability of the resources was good. Six publications detail decision aid development and/or evaluation research. Using PtDAs improved treatment decision-making by patients. Only resources identified as PtDAs and available in English were included. Conclusions: PtDAs are used by some services to support patients choosing between dialysis options or end-of-life options. PtDAs developed to proactively support people making informed decisions between conservative management and dialysis treatments are likely to enable services to meet current best practice

Dialysis vs conservative management decision aid: a study protocol

When patients' kidney function deteriorates to chronic kidney disease stage 5, services offer patients a choice for the next phase of their care. Renal replacement therapies may not have survival benefits, and conservative management may have less treatment burden for older patients with associated comorbidities or frailty. Anna E Winterbottom et al discuss the development of a patient decision aid

Critical review of leaflets about conservative management used in UK renal services

Background: Written information supplements nurse‐led education about treatment options. It is unclear if this information enhances patients’ reasoning about conservative management (CM) and renal replacement therapy decisions. Aim: This study describes a critical review of resources U.K. renal staff use when providing CM options to people with Established Kidney Disease (EKD) during usual pre‐dialysis education. Design: A survey using mixed methods identified and critically analysed leaflets about CM. Participants & measurements: All 72 renal units in the United Kingdom received an 11‐item questionnaire to elicit how CM education is delivered, satisfaction and/or needs with patient resources and staff training. Copies of leaflets were requested. A coding frame was utilised to produce a quality score for each leaflet. Results: Fifty‐four (75%) units participated. Patients discuss CM with a nephrologist (98%) or nurse (100%). Eighteen leaflets were reviewed, mean scores were 8.44 out of 12 (range 5–12, SD = 2.49) for information presentation; 3.50 out of 6 (range 0–6, SD = 1.58) for inclusion of information known to support shared decision‐making and 2.28 out of 6 (range 1–4, SD = 0.96) for presenting non‐biased information. Conclusions: Nurses preferred communicating via face‐to‐face contact with patients and/or families because of the emotional consequences and complexity of planning treatment for the next stage of a person's worsening kidney disease. Conversations were supplemented with written information; 66% of which were produced locally. Staff perceived a need for using leaflets, and spend time and resources developing them to support their services. However, no leaflets included the components needed to help people reason about conservative care and renal replacement therapy options during EKD education consultations

Promoviendo la justicia social a través del aprendizaje-servicio en la formación de maestros de Educación Infantil

As early childhood teacher education programs have begun to place greater emphasis on standards and accountability, there has been less focus on working with the community, and especially working on important social justice issues (Kroll, 2013). In this paper we argue that integrating service-learning and teacher education is a strategy for increasing awareness of social justice issues for young children, age three to grade three. Through the use of questionnaires and interviews to collect our data, we found that implementing a cascading service-learning model in teacher education programs has a positive transformative effect on Pre-Service Teachers. Additionally, we examined the effects of social justice service-learning projects on young children. The results from the data indicated that implementing a social justice service-learning project with these participants had a great impact or transformation on them.Como en los programas de formación del profesorado para la primera infancia han empezado a poner mayor énfasis en los estándares y la rendición de cuentas, se está haciendo menos hincapié en el trabajo con la comunidad, y especialmente en trabajos centrados en temas relevantes de justicia social (Kroll, 2013). En este artículo se argumenta que la integración del aprendizaje-servicio y la formación del profesorado es una estrategia para aumentar la conciencia sobre temas de justicia social con los niños pequeños, desde los tres años hasta tercer grado. A través del uso de cuestionarios y entrevistas para la recolección de datos, se encontró que la implementación de un modelo de aprendizaje-servicio en cascada en los programas de formación del profesorado tiene un efecto transformador positivo en profesores en formación. Además, se examinaron los efectos de los proyectos de aprendizaje-servicio de justicia social con niños pequeños. Los resultados de los datos indican que la implementación de un proyecto de aprendizaje-servicio de justicia social con estos participantes tiene un gran impacto o transformación en ellos.Os programas de formação do professorado para a primeira infância começaram a pôr maior ênfase nos padrões e a prestação de contas, dando-se menos ênfase ao trabalho com a comunidade, e especialmente em trabalhos centrados em temas relevantes de justiça social (Kroll, 2013). Neste artigo se argumenta que a integração do aprendizagem-serviço e a formação do professorado é uma estratégia para aumentar a consciência sobre temas de justiça social com as crianças pequenas, desde os três anos até o terceiro grau. Através do uso de questionário e entrevistas para a coleta de dados, encontrou-se que a implementação de um modelo de aprendizagem-serviço em cascata nos programas de formação de professores tem um efeito transformador positivo em professores em formação. Ademais, examinaramse os efeitos dos projetos de aprendizagem-serviço de justiça social com crianças pequenas. Os resultados dos dados indicam que a implantação de um projeto de aprendizagem-serviço de justiça social com estes participantes causa neles um grande impacto ou transformação

Psychosocial difficulties, deprivation and cancer: three questionnaire studies involving 609 cancer patients

The aim of the study is to investigate associations between deprivation and self-reported social difficulties and psychological distress in cancer patients. A total of 304 men and 305 women (age range 18–88 years) with a range of cancer diagnoses and living in a socially diverse region (Carstairs and Morris index) completed the Hospital Anxiety and Depression Scale and the Social Difficulties Inventory. Univariate analyses of variance revealed statistically significant differences in reported social difficulties between groups (F (67, 576)=2.4, P<0.0001) with stage of disease (F (5, 576)=7.6, P<0.0001), age (F (2, 576)=4.8, P=0.009) and to a lesser extent deprivation (F (1, 576)=4.0, P=0.048) making significant contributions. Significantly more social difficulties were reported by less affluent patients with locally recurrent disease or ‘survivors'. No other interactions were found. Significant differences in levels of reported psychological distress were found between groups (F (67, 575)=1.723, P=0.001) for stage of disease, sex and deprivation but no interactions observed. In conclusion, deprivation is associated with reported psychological distress and, to a lesser extent, social difficulties. Patients at particular risk cannot be identified with confidence by socio-demographic and clinical means supporting the recommendation from National Institute for Clinical Excellence for provision of psychosocial assessment for individual cancer patients

A lattice model for the line tension of a sessile drop

Within a semi--infinite thre--dimensional lattice gas model describing the coexistence of two phases on a substrate, we study, by cluster expansion techniques, the free energy (line tension) associated with the contact line between the two phases and the substrate. We show that this line tension, is given at low temperature by a convergent series whose leading term is negative, and equals 0 at zero temperature

Au/TiO2(110) interfacial reconstruction stability from ab initio

We determine the stability and properties of interfaces of low-index Au surfaces adhered to TiO2(110), using density functional theory energy density calculations. We consider Au(100) and Au(111) epitaxies on rutile TiO2(110) surface, as observed in experiments. For each epitaxy, we consider several different interfaces: Au(111)//TiO2(110) and Au(100)//TiO2(110), with and without bridging oxygen, Au(111) on 1x2 added-row TiO2(110) reconstruction, and Au(111) on a proposed 1x2 TiO reconstruction. The density functional theory energy density method computes the energy changes on each of the atoms while forming the interface, and evaluates the work of adhesion to determine the equilibrium interfacial structure.Comment: 20 pages, 11 figure