NOx storage-reduction characteristics of Ba-based lean NOx trap catalysts subjected to simulated road aging

In order to study the effect of washcoat composition on lean NOx trap (LNT) aging characteristics, fully formulated monolithic LNT catalysts containing varying amounts of La-stabilized CeO2 (5 wt% La2O3) or CeO2-ZrO2 (Ce:Zr = 70:30) were subjected to accelerated aging on a bench reactor. Subsequent catalyst evaluation revealed that aging resulted in deterioration of the NOx storage, NOx release and NOx reduction functions, whereas the observation of lean phase NO2 slip for all of the aged catalysts indicated that LNT performance was not limited by the kinetics of NO oxidation. After aging, all of the catalysts showed increased selectivity to NH3 in the temperature range 250–450 °C. TEM, H2 chemisorption, XPS and elemental analysis data revealed two main changes which can explain the degradation in LNT performance. First, residual sulfur in the catalysts, present as BaSO4, decreased catalyst NOx storage capacity. Second, sintering of the precious metals in the washcoat was observed, which can be expected to decrease the rate of NOx reduction. Additionally, sintering is hypothesized to result in segregation of the precious metal and Ba phases, resulting in less efficient NOx spillover from Pt to Ba during NOx adsorption, as well as decreased rates of reductant spillover from Pt to Ba and reverse NOx spillover during catalyst regeneration. Spectacular improvement in LNT durability was observed for catalysts containing CeO2 or CeO2-ZrO2 relative to their non-ceria containing analog. This was attributed to (i) the ability of ceria to participate in NOx storage/reduction as a supplement to the main Ba NOx storage component; (ii) the fact that Pt and CeO2(-ZrO2) are not subject to phase segregation; and (iii) the ability of ceria to trap sulfur, resulting in decreased sulfur accumulation on the Ba component.

The primary amine metabolite of sibutramine stimulates lipolysis in adipocytes isolated from lean and obese mice and in isolated human adipocytes

Sibutramine is a satiety-inducing serotonin-noradrenaline reuptake inhibitor that acts predominantly via its primary and secondary metabolites. This study investigates the possibility that sibutramine and/or its metabolites could act directly on white adipose tissue to increase lipolysis. Adipocytes were isolated by a collagenase digestion procedure from homozygous lean (+/+) and obese-diabetic ob/ob mice, and from lean nondiabetic human subjects. The lipolytic activity of adipocyte preparations was measured by the determination of glycerol release over a 2-hour incubation period. The primary amine metabolite of sibutramine M2, caused a concentration-dependent stimulation of glycerol release by murine lean and obese adipocytes (maximum increase by 157 ± 22 and 245 ± 1696, respectively, p < 0.05). Neither sibutramine nor its secondary amine metabolite M1 had any effect on lipolytic activity. Preliminary studies indicated that M2-induced lipolysis was mediated via a beta-adrenergic action. The non-selective beta-adrenoceptor antagonist propranolol (10-6M) strongly inhibited M2-stimulated lipolysis in lean and obese murine adipocytes. M2 similarly increased lipolysis by isolated human omental and subcutaneous adipocytes (maximum increase by 194 ± 33 and 136 ± 4%, respectively, p < 0.05) with EC50 values of 12 nM and 3 nM, respectively. These results indicate that the sibutramine metabolite M2 can act directly on murine and human adipose tissue to increase lipolysis via a pathway involving beta-adrenoceptors. © Georg Thieme Verlag KG Stuttgart.

Special Features of Musical Education in Distant Learning (Training of Intonation Thinking)

The problem of using modern technologies in distant learning of intonation thinking is described in this article. An importance of intonation learning for musician students and the possibilities, provided by World Wide Web and multimedia technologies are the main point of this article.

Broadening the evidence base and the mind when thinking about mixed methods research

On behalf of my coauthors, Dr Michael Larkin and Professor Paul Flowers, and I would like to thank Dr Pierre Pluye for his letter in response to our article.1 Dr Pluye supported our argument that a broader evidence base is needed in evidence-based healthcare. He provided the readers of this journal with important additional information which updates them on the progress in the area of mixed studies reviews and further detail about the Mixed Methods Appraisal Tool (MMAT).2 Since writing our …

Shared cognitive processes underlying past and future thinking:the impact of imagery and concurrent task demands on event specificity

Recent literature has argued that whereas remembering the past and imagining the future make use of shared cognitive substrates, simulating future events places heavier demands on executive resources. These propositions were explored in 3 experiments comparing the impact of imagery and concurrent task demands on speed and accuracy of past event retrieval and future event simulation. Results provide support for the suggestion that both past and future episodes can be constructed through 2 mechanisms: a noneffortful "direct" pathway and a controlled, effortful "generative" pathway. However, limited evidence emerged for the suggestion that simulating of future, compared with retrieving past, episodes places heavier demands on executive resources; only under certain conditions did it emerge as a more error prone and lengthier process. The findings are discussed in terms of how retrieval and simulation make use of the same cognitive substrates in subtly different ways. © 2011 American Psychological Association.

Basic Principles of Organization of the Medium and Thinking Process of the Human in its Conceptual Presentation

Given in the report conceptual presentation of the main principles of fractal-complexity Ration of the media and thinking processes of the human was formulated on the bases of the cybernetic interpretation of scientific information (basically from neurophysiology and neuropsychology, containing the interpretation giving the best fit to the authors point of view) and plausible hypothesis's, filling the lack of knowledge.

Development of Variational Thinking Skills in Programming Teaching

The paper presents an example of methodological approach to the development of variational thinking skills in teaching programming. Various ways in solving a given task are implemented for the purpose. One of the forms, through which the variational thinking is manifested, is related to trail practical actions. In the process of comprehension of the properties thus acquired, students are doing their own (correct or incorrect) conclusions for other, hidden properties and at the same time they discover possibilities for new ways of action and acquiring of new effects. The variability and the generalizing function of thinking are in a close interrelation, and their interaction to a great extend determines the dynamics of the cognitive activity of the student.

Acceptability of Lean Six Sigma in a developing economy:results from exploratory research in Nigerian consulting companies

The application of Lean Six Sigma (LSS) varies in different regions of the world in terms of both level of understanding and acceptability. Employing a qualitative methodological approach, this paper aims to explore factors hindering the acceptability of the LSS initiative in organizations and list factors required for successful application and implementation in a developing economy from the perspective of LSS consultants. Using Nigeria as a case study, primary data were collected though a number of semi-structured interviews with representatives of leading continuous improvement consultancy firms in Nigeria. Finding draws out links between major factors such as drivers and motivation, LSS performance, marketability and challenges to the acceptability and applicability of LSS in Nigeria. Further findings highlight major factors such as lack of management buy-in, level of awareness, certification driven market, Nigerian environment and culture, etc as problems that hinder successful implementation of LSS in Nigeria. This paper contributes to the theoretical foundation of critical success factors required for the implementation of Lean Six Sigma, with results from the experience of a developing economy.

Developing Students’ Mathematical Thinking and Algorithmic Culture in IT Classes

Report published in the Proceedings of the National Conference on "Education in the Information Society", Plovdiv, May, 2012

Towards the strategic adoption of Lean in aviation Maintenance Repair and Overhaul (MRO) industry:an empirical study into the industry's Lean status

Purpose - Despite many Maintenance Repair and Overhaul (MRO) organisations alluding their positive business performances to the adoption Lean initiatives, there is a paucity of direct literature that validates this assertion. Thus, the purpose of this paper is to study empirically via the use of an industry-wide survey to establish and extent of Lean adoption and to verify its suitability in mitigating prevalent MRO challenges. Design/methodology/approach - The empirical study contained in this paper is facilitated by an industry-wide survey to collect data from several firms across the MRO spectrum. The analysed responses from industry leaders, professionals and executives synthesised with existing literature was used in ascertaining the extent of Lean adoption within the operational framework of the industry. Findings - The empirical study helped in validating the suitability of Lean in MRO context. However, it was also observed that the focus of its application was skewed towards its production-orientated functions more than its service-orientated functions. Nonetheless, this paper presents results of the positive influence of Lean in MRO context. Research limitations/implications - This empirical study presented in this paper was carried out within a framework of key characteristics of operation. Although this approach is sufficient in assessing the industry's Lean status, further assessment can also be achieved within the context of relevant performance metrics which was not included in this paper. Practical implications - By exploring the industry's Lean status within the context of operational characteristics of operation, this study provides MRO practitioners with more awareness into some of the critical factors required for successful holistic Lean realisation. Social implications - The state-of-the-art of Lean within the aviation MRO context established through this research also contributes to the wider product-centric service environment by providing a platform that facilitates strategy development which ensures Lean success within this environment. Originality/value - Apart from validating the suitability of Lean in MRO contexts, by establishing the extent of Lean adoption within the context of the operational framework, this paper provides a clearer insight as to how successful Lean implementation can be achieved via a holistic implementation strategy balanced between the product-centric and service-centric aspects of the industry.

Women’s adaptation to STEM domains promotes resilience and a lesser reliance on heuristic thinking

Experiences that compel people to challenge social stereotypes can promote enhanced cognitive flexibility on a range of judgmental domains. Women in STEM (science, technology, engineering, and math) fields are chronically exposed to such experiences and may therefore also demonstrate these benefits. Two studies examined the differential effects of counterstereotypical experiences on women from STEM and non-STEM fields. Results showed that imagining or recollecting these experiences led women from STEM fields to exhibit a lesser reliance on heuristic thinking compared to women from non-STEM fields, and this difference was mediated by self-perceived resilience to the negative impact of gender stereotyping. Implications for psychologists’ and educators’ understanding of the relationship between counterstereotypical experiences and heuristic thinking are discussed.

Creative thinking experimentations for entrepreneurship with a disruptive, personalised and mobile game-based learning ecosystem

Based on an unprecedented need of stimulating creative capacities towards entrepreneurship to university students and young researchers, this paper introduces and analyses a smart learning ecosystem for encouraging teaching and learning on creative thinking as a distinct feature to be taught and learnt in universities. The paper introduces a mashed-up authoring architecture for designing lesson-plans and games with visual learning mechanics for creativity learning. The design process is facilitated by creativity pathways discerned across components. Participatory learning, networking and capacity building is a key aspect of the architecture, extending the learning experience and context from the classroom to outdoor (co-authoring of creative pathways by students, teachers and real-world entrepreneurs) and personal spaces. We anticipate that the smart learning ecosystem will be empirically evaluated and validated in future iterations for exploring the benefits of using games for enhancing creative mindsets, unlocking the imagination that lies within, practiced and transferred to multiple academic tribes and territories.