Resistance of alkali activated slag concretes to chloride environments based on chloride penetration measurements

ABSTRACT

One of the binder systems with low environmental footprint is alkali activated slag concretes (AASC), made by adding alkalis such as sodium hydroxide and sodium silicate to industrial by-products such as ground granulated blast furnace slag (GGBS). Whilst they have the similar behaviour as that of traditional cement systems in terms of strength and structural behaviour, AASC do exhibit superior performance in terms of abrasion and acid resistance and fire protection.
In this article, the authors focus their attention on chloride ingress into different grades of AASC. The mix variables in AASC included water-to-binder, binder to aggregate ratio, percentage of alkali and the SiO2/Na2O ratio (silica modulus, Ms). The first challenge is to get mixes for different range of workability (with slump values from 40mm to 240mm) and reasonable early age and long term compressive strength according to each one. Then the chloride diffusion and migration in those mixes were measured and compared with same normal concretes in the existed literature based on chloride penetration depth. Comparing the chloride ingress between tradition concretes and AASCs is worthwhile to prove the possibility of increasing concrete lifetime in proximity to sea and deciding while such concretes are practical for use. Findings show that compared to the PC concretes, the AAS concretes have lower rate of chloride ingress.

Numerical simulations of fluid-structure interactions in single-reed mouthpieces

Most single-reed woodwind instrument models rely on a quasistationary approximation to describe the relationship between the volume flow and. the pressure difference across the reed channel. Semiempirical models based on the quasistationary approximation are very useful in explaining the fundamental characteristics of this family of instruments such as self-sustained oscillations and threshold of blowing pressure. However, they fail at explaining more complex phenomena associated with the fluid-structure interaction during dynamic flow regimes, such as the transient and steady-state behavior of the system as a function. of the mouthpiece geometry. Previous studies have discussed the accuracy of the quasistationary approximation but the amount of literature on the subject is sparse, mainly due to the difficulties involved in the measurement of dynamic flows in channels with an oscillating reed. In this paper, a numerical technique based on the lattice Boltzmann method and a finite difference scheme is proposed in order to investigate the characteristics of fully coupled fluid-structure interaction in single-reed mouthpieces with different channel configurations. Results obtained for a stationary simulation with a static reed agree very well with those predicted by the literature based on the quasistationary approximation. However, simulations carried out for a dynamic regime with dn oscillating reed show that the phenomenon associated with flow detachment and reattachment diverges considerably frorn the theoretical assumptions. Furthermore, in the case of long reed channels, the results obtained for the vena contracta factor are in significant disagreement with those predicted by theory. For short channels, the assumption of constant vena contracta was found to be valid for only 40% of the duty cycle. (c) 2007 Acoustical Society of America.

Can the scaling behavior of electric conductivity be used to probe the self-organizational changes in solution with respect to the ionic liquid structure? The case of [C8MIM][NTf2]

Electrical conductivity of the supercooled ionic liquid [C8MIM][NTf2], determined as a function of temperature and pressure, highlights strong differences in its ionic transport behavior between low and high temperature regions. To date, the crossover effect which is very well known for low molecular van der Waals liquids has been rarely described for classical ionic liquids. This finding highlights that the thermal fluctuations could be dominant mechanisms driving the dramatic slowing down of ion motions near Tg. An alternative way to analyze separately low and high temperature dc-conductivity data using a density scaling approach was then proposed. Based on which a common value of the scaling exponent [gamma] = 2.4 was obtained, indicating that the applied density scaling is insensitive to the crossover effect. By comparing the scaling exponent [gamma] reported herein along with literature data for other ionic liquids, it appears that [gamma] decreases by increasing the alkyl chain length on the 1-alkyl-3-methylimidazolium-based ionic liquids. This observation may be related to changes in the interaction between ions in solution driven by an increase in the van der Waals type interaction by increasing the alkyl chain length on the cation. This effect may be related to changes in the ionic liquid nanostructural organization with the alkyl chain length on the cation as previously reported in the literature based on molecular dynamic simulations. In other words, the calculated scaling exponent [gamma] may be then used as a key parameter to probe the interaction and/or self-organizational changes in solution with respect to the ionic liquid structure.

Max Weber and the First World War: Protestant and Catholic living standards in Germany, 1914-1919

We assess informal institutions of Protestants and Catholics by investigating their economic resilience in a natural experiment. The First World War constitutes an exogenous shock to living standards since the duration and intensity of the war exceeded all expectations. We assess the ability of Protestant and Catholic communities to cope with increasing food prices and wartime black markets. Literature based on Weber (1904, 1905) suggests that Protestants must be more resilient than their Catholic peers. Using individual height data on some 2,800 Germans to assess levels of malnutrition during the war, we find that living standards for both Protestants and Catholics declined; however, the decrease of Catholics’ height was disproportionately large. Our empirical analysis finds a large statistically significant difference between Protestants and Catholics for the 1915–19 birth cohort, and we argue that this height gap cannot be attributed to socioeconomic background and fertility alone.

Max Weber and the First World War: Protestant and Catholic living standards in Germany, 1915-1919

We assess informal institutions of Protestants and Catholics by investigating their economic
resilience in a natural experiment. The First World War constitutes an exogenous shock to living standards since the duration and intensity of the war exceeded all expectations. We assess the ability of Protestant and Catholic communities to cope with increasing food prices and wartime black markets. Literature based on Weber (1904, 1905) suggests that Protestants must be more resilient than their Catholic peers. Using individual height data on some 2,800 Germans to assess levels of malnutrition during the war, we find that living standards for both Protestants and Catholics declined; however, the decrease of Catholics’ height was disproportionately large. Our empirical analysis finds a large statistically significant difference between Protestants and Catholics for the 1914-19 birth cohort, and we argue that this height gap cannot be attributed to socioeconomic background and fertility alone.

Evidence-based practice: the relevance of systematic reviews.

Aim:
To demonstrate how systematic reviews provide robust evidence to inform clinical decision making in practice.

Background
Systematic reviews collate findings from a number of research studies in order to provide a comprehensive and reliable summary of the best available evidence. The use of systematic reviews to inform practice based decisions has increased as a result of the overwhelming amount of research literature available, poor quality of research evidence and the need to ensure practice is based upon the best available evidence. Systematic reviews are an efficient way of coping with large volumes of data to answer focused research questions. They differ from traditional literature reviews as they adhere to an explicit scientific process. The use of explicit and rigorous methods to identify, appraise and synthesise relevant studies minimises bias and provides a reliable basis for decision making. As a result systematic reviews provide clear evidence on the effectiveness of a healthcare intervention to inform policy and decision making across healthcare systems. An example of how the findings from systematic reviews can provide reliable evidence to inform healthcare decisions will be provided in this presentation1. This will demonstrate how focused clinical questions can be answered by systematic reviews and translated into practice.

Reference:
1. McGaughey J, Alderdice F, Fowler R, Kapila A, Moutray M. (2007) Outreach and Early Warning Systems (EWS) for the prevention of Intensive Care admission admission and death of critically ill adult patients on general hospital wards (REVIEW). The Cochrane Database of Systematic Reviews 3. art no CD005529

Approved Social Work Training in Northern Ireland: Using Research to Examine Competence-Based Learning and Influence Policy Change

This article reports on how research activity helped describe and analyse ASW (Approved Social Worker) learning experience as well as acting as a catalyst for change and development in policy and practice in Northern Ireland. The paper contextualizes the study by outlining the legislation, the main features of the ASW role and the approach to ASW training in Northern Ireland, and by reviewing the literature on the efficacy and value of competence-based learning. While the findings do not provide conclusive evidence that a competence-based approach is inherently more effective than previous courses, they do indicate that candidates who were trained in this way were moderately more satisfied than those who had participated in non-competence based programmes. The research also highlights the importance of the interrelationship between training, practice experience and support in developing and sustaining competence. The paper concludes with a review of the recommendations arising from the study and an analysis of the developments in training and regulations relating to practice experience and re-approval of ASWs since publication of the research. The study is of contemporary interest given the proposed changes to the role of ASWs/Mental Health Officers in the context of the reviews of UK mental health law.

Bereavement needs assessment in specialist palliative care: A review of the literature

Bereavement needs assessment for specialist palliative care services has been highlighted as important by NICE guidance on palliative care for adults with cancer. Identifying and implementing appropriate bereavement measurement tools has remained a challenge. This paper identifies and reviews bereavement measurement tools to determine their suitability for use within bereavement services and hospice settings. Cochrane, MEDLINE, PsycINFO and CINAHL, electronic databases were searched, yielding 486 papers. From fifty-nine full text papers appraised, 10 measurement tools were analysed in detail. Some tools had been tested on specific populations which limited transferability to specialist palliative care settings; some lacked adequate theoretical links and were not effective in discriminating between normal and complicated grief reactions; and some lacked clear evidence of validity or reliability. Based on these criteria, conclusions are drawn about the suitability of particular tools for UK bereavement services and hospice settings where intervention is delivered by both trained professionals and volunteers.

Indirect comparisons of treatments based on systematic reviews of randomised controlled trials

Randomised controlled trials are the most effective way to differentiate between the effects of competing interventions. However, head-to-head studies are unlikely to have been conducted for all competing interventions.

Developing Evidence-Based Practice in Child Protection

This article argues for the adoption of an evidence-based approach to decision-making in child protection. Such a change hinges upon the availability of good quality, up-to-date evidence that is readily accessible to practitioners and policy-makers. Following a resume' of the arguments for recognizing controlled trials as methodologically superior to other forms of methodology in evaluating professional interventions, the article presents the case for adopting a similarly rigorous approach to synthesizing research findings. It then identifies a range of obstacles to promoting evidence-based practice and makes recommendations for changes in training, research, and practice which might facilitate improvement in both primary research and in reviews of the literature.

A literature review of end-stage renal disease and cachexia:Understanding experience to inform evidence-based healthcare

Introduction: Cachexia is a major cause of morbidity and mortality in people who have end-stage renal disease (ESRD). The majority of research into cachexia in ESRD has focused on the biological aspects of the syndrome and potential treatment modalities. While this research is necessary, it predominately focuses on the physical impact of cachexia in ESRD. The multi-dimensional psychosocial ramifications of this syndrome have been highlighted in other end-stage illness trajectories, but have not been systematically explored in persons who have ESRD. Aim: This paper discusses why this research is necessary, alongside further studies to help define the pathophysiology of this syndrome. Conclusion: The rich insightful data gained from understanding the patients' illness experience will positively contribute to the limited knowledge base available and inform future holistic patient-centred care delivery which recognises and responds to not only the biological but also the psychosocial impact of cachexia. © 2013 European Dialysis and Transplant Nurses Association/European Renal Care Association.

What Are the Effects of Teaching Evidence-Based Health Care (EBHC)? Overview of Systematic Reviews

Background

An evidence-based approach to health care is recognized internationally as a key competency for healthcare practitioners. This overview systematically evaluated and organized evidence from systematic reviews on teaching evidence-based health care (EBHC).

Methods/Findings

We searched for systematic reviews evaluating interventions for teaching EBHC to health professionals compared to no intervention or different strategies. Outcomes covered EBHC knowledge, skills, attitudes, practices and health outcomes. Comprehensive searches were conducted in April 2013. Two reviewers independently selected eligible reviews, extracted data and evaluated methodological quality. We included 16 systematic reviews, published between 1993 and 2013. There was considerable overlap across reviews. We found that 171 source studies included in the reviews related to 81 separate studies, of which 37 are in more than one review. Studies used various methodologies to evaluate educational interventions of varying content, format and duration in undergraduates, interns, residents and practicing health professionals. The evidence in the reviews showed that multifaceted, clinically integrated interventions, with assessment, led to improvements in knowledge, skills and attitudes. Interventions improved critical appraisal skills and integration of results into decisions, and improved knowledge, skills, attitudes and behaviour amongst practicing health professionals. Considering single interventions, EBHC knowledge and attitude were similar for lecture-based versus online teaching. Journal clubs appeared to increase clinical epidemiology and biostatistics knowledge and reading behavior, but not appraisal skills. EBHC courses improved appraisal skills and knowledge. Amongst practicing health professionals, interactive online courses with guided critical appraisal showed significant increase in knowledge and appraisal skills. A short workshop using problem-based approaches, compared to no intervention, increased knowledge but not appraisal skills.

Conclusions

EBHC teaching and learning strategies should focus on implementing multifaceted, clinically integrated approaches with assessment. Future rigorous research should evaluate minimum components for multifaceted interventions, assessment of medium to long-term outcomes, and implementation of these interventions.

A review of behaviour change theories and techniques used in group based self-management programmes for chronic low back pain and arthritis

Background: Medical Research Council (MRC) guidelines recommend applying theory within complex interventions to explain how behaviour change occurs. Guidelines endorse self-management of chronic low back pain (CLBP) and osteoarthritis (OA), but evidence for its effectiveness is weak. Objective: This literature review aimed to determine the use of behaviour change theory and techniques within randomised controlled trials of group-based self-management programmes for chronic musculoskeletal pain, specifically CLBP and OA. Methods: A two-phase search strategy of electronic databases was used to identify systematic reviews and studies relevant to this area. Articles were coded for their use of behaviour change theory, and the number of behaviour change techniques (BCTs) was identified using a 93-item taxonomy, Taxonomy (v1). Results: 25 articles of 22 studies met the inclusion criteria, of which only three reported having based their intervention on theory, and all used Social Cognitive Theory. A total of 33 BCTs were coded across all articles with the most commonly identified techniques being '. instruction on how to perform the behaviour', '. demonstration of the behaviour', '. behavioural practice', '. credible source', '. graded tasks' and '. body changes'. Conclusion: Results demonstrate that theoretically driven research within group based self-management programmes for chronic musculoskeletal pain is lacking, or is poorly reported. Future research that follows recommended guidelines regarding the use of theory in study design and reporting is warranted.

Challenges of minimizing heat loss at birth: A narrative overview of evidence-based thermal care interventions

Evidence-based thermal care recommendations designed to minimize heat loss immediately at birth are readily available however, hypothermia still persists as a global challenge especially when caring for the most immature and smallest preterm infants. In this narrative overview we aim to provide the reader with a succinct summary of the causes and consequences of hypothermia, the extent of the problem (rates of hypothermia), principles of good thermal care, delivery room preventative measures, the research evidence underpinning existing interventions, current issues in practice, and the way forward. Due to the plethora of research literature available in this subject area, our article will focus primarily on evidence derived from systematic reviews and randomized or quasi-randomized controlled trials assessing the effectiveness of interventions to prevent hypothermia in the most vulnerable (preterm/low birth weight) infants where the intervention or combination of interventions is applied immediately at birth. © 2014.