Experimental Design to Optimize High-Volume Ash Grout in the Presence of Welan Gum and Superplasticizer

Applications such as soil, rock and oil-well grouting all require enormous amounts of cement and are good examples of areas where a high volume of fly ash could partially replace cement to produce low-cost, environmentally safe and durable concrete. There is an increasing need to identify the rheological properties of cement grout using a simple test to determine the fluidity, and other properties of underwater grouts such as washout resistance and compressive strength. This paper presents statistical models developed using a fractorial design which was carried out to model the influence of key parameters on properties affecting the performance of underwater grout. Such responses of fluidity included mini-slump and flow time measured by Marsh cone, washout resistance, unit weight and compressive strength. The models are valid for mixes with 0.40 to 0.60 water-to-cementitious materials ratio, 0.02 to 0.08% of anti-washout admixture, by mass of binder, and 0.6 to 1.8% of superplasticizer, by mass of cementitious materials. The grout was made with 50% of pulverized-fuel ash replacement, by mass ofcementitious materials. Also presented are the derived models that enable the identification of underlying primary factors and their interactions that influence the modelled responses of underwater cement grout. Such parameters can be useful to reduce the test protocol needed for proportioning of underwater cement grout. This paper highlighted the influence of W/CM and dosage of antiwashout admixture and superplasticizer on fluidity, washout resistance and compressive strength and attempted also to demonstrate the usefulness of the models to improve understanding of trade-offs between parameters.

New peace, new teachers: student teachers’ perspectives on diversity and community relations in Northern Ireland

This paper reflects upon student teachers’ conceptions of inter-community relations and the preparation they receive to address issues of diversity and mutual understanding. The study in Northern Ireland is set against a backdrop of political, social and educational change, where a shared, peaceful future appears possible. Student teachers at a Catholic institution and a predominantly Protestant institution indicated a willingness to engage with issues concerning diversity and inter-community relations, despite having a limited knowledge of the concepts. However they also demonstrated clear views about the relevance and value of the preparation they received. The findings are evaluated using multicultural theory.

Expression of the counter-regulatory peptide intermedin is augmented in the presence of oxidative stress in hypertrophied cardiomyocytes.

Background: Intermedin (IMD), a novel cardiac peptide related to adrenomedullin (AM), protects against myocardial ischemia-reperfusion injury and attenuates ventricular remodelling. IMD’s actions are mediated by a calcitonin receptor-like receptor in association with receptor activity modifying proteins (RAMPs 1-3). Aim/method: using the spontaneously hypertensive rat (SHR) and normotensive Wistar Kyoto (WKY) rat at 20 weeks of age, to examine (i) the presence of myocardial oxidative stress and concentric hypertrophy; (ii) expression of IMD, AM and receptor components. Results: In left and right ventricular cardiomyocytes from SHR vs. WKY cell width (26% left, 15% right) and mRNA expression of hypertrophic markers ANP (2.7 fold left, 2.7 fold right) and BNP (2.2 fold left, 2.0 fold right) were enhanced. In left ventricular cardiomyocytes only (i) oxidative stress was indicated by increased membrane protein carbonyl content (71%) and augmented production of O2- anion (64%); (ii) IMD (6.8 fold), RAMP1 (2.5 fold) and RAMP3 (2.0 fold) mRNA was increased while AM and RAMP2 mRNA was not altered; (iii) abundance of RAMP1 (by 48%), RAMP2 (by 41%) and RAMP3 (by 90%) monomers in cell membranes was decreased. Conclusion: robust augmentation of IMD expression in hypertrophied left ventricular cardiomyocytes indicates a prominent role for this counter-regulatory peptide in the adaptation of the SHR myocardium to the stresses imposed by chronic hypertension. The local concentration and action of IMD may be further enhanced by down-regulation of NEP within the left ventricle.

Teachers’ understandings of reconciliation and inclusion in four troubled societies.

In this article, the authors examine how teachers in four troubled societies – Israel, Cyprus, Northern Ireland and South Africa – understand and implement reconciliation in light of the increasing diversity of these societies. The authors particularly pay attention to a dialogical encounter between reconciliation and inclusion, as they look for ways to contemplate how each might be of mutual benefit in educational theory and practice. In the first part of the article, the authors give an overview of current thinking on reconciliation and its role in education, and suggest that the notion of inclusiveness can enrich it. The context of the research is then provided by looking briefly at the socio-political and educational settings in which the study was conducted, followed by a discussion of the research methodology. The findings from the study are then presented with the main themes identified as arising across the four research locations. These themes concern understandings of reconciliation and inclusion, student diversity, teachers’ challenges, helping students deal with conflict, and teachers’ development. Finally, whilst acknowledging the exploratory nature of these findings, the authors discuss what policy makers, school leaders and teachers might change about policies and practices for reconciliation education in the four settings studied and, by implication, other comparable settings.

Child abuse and neglect: Training needs of student teachers

Increasing awareness of child abuse and neglect (CAN) raises questions about how well teachers are prepared for their role in child protection. This paper assesses and differentiates training needs of first-year students (n = 216) in Northern Ireland. Multiplechoice tests were used to assess knowledge of CAN statistics; recognising and reporting; policies, procedures, and legislative frameworks; and direct work with children. Considerable gaps in knowledge were found. Results between student groups varied and provide evidence of the need to develop pre-service child protection training. The importance of differentiation between student groups in terms of training content is emphasised.

CD207+ CD103+ dermal dendritic cells cross-present keratinocyte-derived antigens irrespective of the presence of Langerhans cells.

Recent studies have challenged the view that Langerhans cells (LCs) constitute the exclusive antigen-presenting cells of the skin and suggest that the dermal dendritic cell (DDC) network is exceedingly complex. Using knockin mice to track and ablate DCs expressing langerin (CD207), we discovered that the dermis contains five distinct DC subsets and identified their migratory counterparts in draining lymph nodes. Based on this refined classification, we demonstrated that the quantitatively minor CD207+ CD103+ DDC subset is endowed with the unique capability of cross-presenting antigens expressed by keratinocytes irrespective of the presence of LCs. We further showed that Y-Ae, an antibody that is widely used to monitor the formation of complexes involving I-Ab molecules and a peptide derived from the I-E alpha chain, recognizes mature skin DCs that express I-Ab molecules in the absence of I-E alpha. Knowledge of this extra reactivity is important because it could be, and already has been, mistakenly interpreted to support the view that antigen transfer can occur between LCs and DDCs. Collectively, these data revisit the transfer of antigen that occurs between keratinocytes and the five distinguishable skin DC subsets and stress the high degree of functional specialization that exists among them.

The growing visibility of creationism in Northern Ireland: are new science teachers equipped to deal with the issues?

The growing visibility of various forms of creationism in Northern Ireland raises issues for science education. Attempts have been made at political levels to have such “alternatives” to evolution taught in the science classroom, and the issue has received coverage in local press and media. A sample of 112 pre-service science teachers answered a survey on attitudes toward evolution. Preliminary analysis revealed many of these new teachers held views contrary to scientific consensus—over one fifth doubt the evidence for human evolution, and over one quarter dispute the common ancestry of life. Over two thirds indicated a preference for teaching a “range of theories” regarding these issues in science. In addition, 49 pre-service biology teachers viewed a DVD resource promoting “intelligent design” and completed an evaluation of it. The biology teachers also took part in either focus groups or additional questionnaires. A majority took the resource at face value and made positive comments regarding its utility. Many articulated views contrary to the stated positions of science academies, professional associations, and the UK government teaching directives regarding creationism. Most indicated a perception that intelligent design is legitimate science and that there is a scientific “controversy” regarding the legitimacy of evolution. Concern is raised over the ability of these new teachers to distinguish between scientific and non-scientific theories. The suggestion is made that the issue should be addressed directly with pre-service science teachers to make clear the status of such “alternatives.” The paper raises implications for science education and questions for further research.

Student teachers' prior experiences of history, geography and science: initial findings of an all-Ireland survey

Research into student teachers' perceptions, attitudes and prior experiences of learning suggests that these experiences can exert an influence on practice which can be relatively undisturbed by their initial teacher education. This article is based on the initial findings of an all-Ireland survey of all first-year students on B.Ed. courses in colleges in Northern Ireland and in the Republic of Ireland. The survey is the first stage in a longitudinal study which will follow the same cohort of students for the duration of their initial teacher education, seeking to map and track the development of their ideas about teaching and learning in primary history, geography and science. Based on an analysis of the quantitative data in the entry questionnaire, the initial findings suggest that subject knowledge remains a problematic issue in initial teacher education and that both location and gender interact with knowledge, attitudes and subject area to produce a complex and challenging context for teacher educators in history, geography and science education.