Numerical investigation of influence of the Martensite Volume Fraction on dp steels fracture behavior on the basis of digital material representation model

Development of the methodology for creating reliable digital material representation (DMR) models of dual-phase steels and investigation of influence of the martensite volume fraction on fracture behavior under tensile load are the main goals of the paper. First, an approach based on image processing algorithms for creating a DMR is described. Then, obtained digital microstructures are used as input for the numerical model of deformation, which takes into account mechanisms of ductile fracture. Ferrite and martensite material model parameters are evaluated on the basis of micropillar compression tests. Finally, the model is used to investigate the impact of the martensite volume fraction on the DP steel behavior under plastic deformation. Results of calculations are presented and discussed in the paper.

The influence of the Mediterranean diet on cognitive health

Neurocognitive function is influenced by a number of systemic biological processes that are susceptible to dietary intervention. It is known, for example, that cardiovascular dysfunction and concomitant inflammatory and oxidative stress processes can negatively effect cognitive function, especially during aging. Indeed, these represent significant risk factors for disorders such as mild cognitive impairment and Alzheimer's disease. A growing body of evidence suggests that adherence to the Mediterranean diet may reduce these pathological processes. It follows that the Mediterranean diet may also positively affect cognitive functioning. This chapter reviews epidemiological studies indicating that the Mediterranean diet supports healthy cognitive aging. Such studies are supported by (relatively rarer) controlled trials, which indicate that switching to the Mediterranean diet may even enhance mood and cognition in younger individuals. Possible mechanisms underlying the association between adherence to the Mediterranean diet and protection against age-related cognitive decline are considered.

Influence of the timing of cardiac surgery on the outcome of patients with infective endocarditis and stroke

BACKGROUND: The timing of cardiac surgery after stroke in infective endocarditis (IE) remains controversial. We examined the relationship between the timing of surgery after stroke and the incidence of in-hospital and 1-year mortalities. METHODS: Data were obtained from the International Collaboration on Endocarditis-Prospective Cohort Study of 4794 patients with definite IE who were admitted to 64 centers from June 2000 through December 2006. Multivariate logistic regression and Cox regression analyses were performed to estimate the impact of early surgery on hospital and 1-year mortality after adjustments for other significant covariates. RESULTS: Of the 857 patients with IE complicated by ischemic stroke syndromes, 198 who underwent valve replacement surgery poststroke were available for analysis. Overall, 58 (29.3%) patients underwent early surgical treatment vs 140 (70.7%) patients who underwent late surgical treatment. After adjustment for other risk factors, early surgery was not significantly associated with increased in-hospital mortality rates (odds ratio, 2.308; 95% confidence interval [CI], .942-5.652). Overall, probability of death after 1-year follow-up did not differ between 2 treatment groups (27.1% in early surgery and 19.2% in late surgery group, P = .328; adjusted hazard ratio, 1.138; 95% CI, .802-1.650). CONCLUSIONS: There is no apparent survival benefit in delaying surgery when indicated in IE patients after ischemic stroke. Further observational analyses that include detailed pre- and postoperative clinical neurologic findings and advanced imaging data (eg, ischemic stroke size), may allow for more refined recommendations on the optimal timing of valvular surgery in patients with IE and recent stroke syndromes.

Influence of grain size on the compressive deformation of wrought Mg-3A1-1Zn

The influence of the grain size on the flow stress of extruded Mg–3Al–1Zn tested in compression is examined. Samples with grain sizes varying between 3 and 23 μm were prepared by altering the extrusion conditions. Compression testing of the extruded bar was carried out at temperatures between ambient and 200 °C. Twinning dominated the deformation at lower temperatures but this gave way to slip dominated flow when the temperature was raised. For tests carried out at intermediate temperatures, a similar transition was observed when the grain size was reduced. The transition was accompanied by a change in flow curve shape and Hall–Petch slope. The peak stresses achieved when twinning dominated the deformation were up to 100 MPa greater than those seen when slip dominated the flow. Critical grain sizes marking the twinning–slip transition were identified and these are described in terms of the deformation conditions.

Temperature dependence of the electrode potential of a cobalt-based redox couple in ionic liquid electrolytes for thermal energy harvesting

Increasing the application of technologies for harvesting waste heat could make a significant contribution to sustainable energy production. Thermoelectrochemical cells are one such emerging technology, where the thermal response of a redox couple in an electrolyte is used to generate a potential difference across a cell when a temperature gradient exists. The unique physical properties of ionic liquids make them ideal for application as electrolytes in these devices. One of the keys to utilizing these media in efficient thermoelectrochemical cells is achieving high Seebeck coefficients, Se: the thermodynamic quantity that determines the magnitude of the voltage achieved per unit temperature difference. Here, we report the Se and cell performance of a cobalt-based redox couple in a range of different ionic liquids, to investigate the influence of the nature of the IL on the thermodynamics and cell performance of the redox system. The results reported include the highest Se to-date for an IL-based electrolyte. The effect of diluting the different ILs with propylene carbonate is also reported, which results in a significant increase in the output powers and current densities of the device.

The influence of marketing logistics networks on organisational performance in Australia and New Zealand

Predictions concerning the influence of traditional and online marketing logistics network competency on organisational performance were tested via structural equation modelling employing a sample of Australian and New Zealand companies. The study finds a significant influence of the use of traditional marketing logistics networks on organisational performance, but that the use of the Web in this regard is yet to have such an influence.

The influence of Sport Education on student motivation in physical education

Background: Physical educators are faced with trying to provide motivating and enjoyable experiences in physical education. Sport Education is an instructional model that aims to provide positive motivational sport experiences by simulating the features of authentic sport. Research support for Sport Education is positive, however, the effects on student motivation and the motivational climate are not well understood.

Purpose: To investigate the influence of the Sport Education model on student motivation (intrinsic/extrinsic motivation, goal orientations, and perceived motivational climate) in secondary physical education.

Setting: Six classes were selected according to teacher and class availability in the sports of soccer, hockey, and football codes in a co-educational government school.

Participants: Participants were 115 (male = 97, female = 18) Year-8 students (aged 13-14 years), in a Sport Education condition (n = 41) and a Traditional condition (n = 74).

Measures: At pre- and post-test, all participants completed three questionnaires: the Intrinsic Motivation Inventory, the Task and Ego Orientation in Sport Questionnaire, and the Perceived Motivational Climate in Sport Questionnaire.

Intervention: Participants completed either a Sport Education condition or a Traditional condition for one double period (100 minutes) one day per week for 10 weeks (Sport Education condition) or for five weeks (Traditional condition). The Sport Education condition incorporated six distinctive features: seasons, affiliation, formal competition, record keeping, festivity, and a culminating event. The Traditional condition used whole-group instruction led by the teacher.

Research design: The study used a non-equivalent control group design with pre- and post-test procedures. The independent variable was teaching condition and the dependent variable was student motivation (assessed by intrinsic motivation, goal orientations, and motivational climate). The groups were already established and selected for convenience purposes.

Data collection and analysis: Participants completed pre-test measures and then participated in their pre-established classes. Post-test measures were completed in the last class in each condition. A reliability analysis on measures was conducted using Cronach's alphas. A pre-test manipulation check was performed to check for any initial differences in motivation. To compare the difference in changes between conditions on motivation, a series of 2 times 2 repeated measures analyses of variance were conducted. A comparison of the relationship between motivation measures was conducted using Pearson's product moment correlation coefficients.

Findings: There was a significant difference between the conditions on changes in perceived competence, task orientation, and mastery climate, with the Traditional condition decreasing significantly from pre- to post-test compared with the Sport Education condition. There were no significant differences on interest/enjoyment, effort/importance, pressure/tension, ego orientation, or performance climate. A mastery climate was positively related to task orientation and intrinsic motivation and a performance climate was related to ego orientation.

Conclusions: The Sport Education condition was more successful in maintaining high levels of intrinsic motivation, task orientation, and mastery climate than the Traditional condition. That is, the Traditional condition was associated with a decrease in adaptive aspects of motivation for students, whereas the Sport Education condition maintained existing levels of motivation.

Evaluation of the thermal behaviour of bevelled cutting inserts using a numerical approach

The nose geometry of a hard and brittle metal cutting tool is generally modified in order to avoid the premature failure due to fracture under tensile stresses. While most research findings point to a favourable mechanical load pattern, the possible influence of the shape of the geometry on the thermal fields and the consequent changes in the stressed state of the tool seem to have attained less attention. The present work aims at establishing the thermal behaviour of bevelled tools under varying geometrical and process parameters. Data generated from statistically designed experiments and quick-stop chip samples are coupled to conduct numerical investigations using a mixed finite and boundary element solution to obtain the temperature distribution in bevelled carbide inserts. Due consideration is given to the presence of the stagnation zone and its size and shape. While the cutting forces and temperatures increased owing to the blunt shape of the tool, the possible absence of tensile stresses was found to be the likely effect of a more uniform temperature distribution resulting from a significant plastic contact on the principal flank and the consequent flank heat source. The characteristic low-temperature zones close to the nose of the conventional tool are taken over by the stagnation zone in bevelled tools. © IMechE 2007.

External policy influence and higher education reform in Ethiopia : understanding symbolic power of the World Bank

Increasingly national policy processes are intersected with and affected by global policy actors and ideas. In aid-recipient countries such as Ethiopia, donors use financial and non-financial means to influence national policy decisions and directions. This paper is about the non-financial influence of the World Bank (WB) in the Ethiopian higher education policy reform. Using Pierre Bourdieu’s concept of symbolic power as a ‘thinking tool’, the paper aims to shed light on forms of symbolic capital that the Bank uses to generate a ‘misrecognisable’ form of power that regulates the HE policy process in Ethiopia. The findings show that the WB transforms its symbolic capital of recognition and legitimacy to establish a ‘shared misrecognition’ and thereby make its policy prescriptions implicit and hence acceptable to local policy agents. The Bank uses knowledge-based regulatory instruments to induce compliance to its neoliberal policy prescriptions. The paper therefore underscores the value of symbol power as an analytical framework to understand elusive but critical role of donors in policy processes of aid recipient countries.

Evolution of the electrochemical capacitance of transition metal oxynitrides with time: the effect of ageing and passivation

A number of transition metal nitrides and oxynitrides, which are actively investigated today as electrode materials in a wide range of energy conversion and storage devices, possess an oxide layer on the surface. Upon exposure to ambient air, properties of this layer progressively change in the process known as "ageing". Since a number of electrochemical processes involve the surface or sub-surface layers of the active electrode compounds only, ageing could have a significant effect on the overall performance of energy conversion and storage devices. In this work, the influence of the ageing of tungsten and molybdenum oxynitrides on their electrochemical properties in supercapacitors is explored for the first time. Samples are synthesised by the temperature-programmed reduction in NH3 and are treated with different gases prior to exposure to air in order to evaluate the role of passivation in the ageing process. After the synthesis, products are subjected to controlled ageing and are characterised by low temperature nitrogen adsorption, X-ray photoelectron spectroscopy and transmission electron microscopy. Capacitive properties of the compounds are evaluated by performing cyclic voltammetry and galvanostatic charge and discharge measurements in the 1 M H2SO4 electrolyte. © 2014 the Partner Organisations.

The environment of inpatient healthcare delivery and its influence on the outcome of care

Aim: This paper addresses issues arising in the literature regarding the environmental design of inpatient healthcare settings and their impact on care.

Background: Environmental design in healthcare settings is an important feature of the holistic delivery of healthcare. The environmental influence of the delivery of care is manifested by such things as lighting, proximity to bedside, technology, family involvement, and space. The need to respond rapidly in places such as emergency and intensive care can override space needs for family support. In some settings with aging buildings, the available space is no longer appropriate to the needs—for example, the need for privacy in emergency departments. Many aspects of care have changed over the last three decades and the environment of care appears not to have been adapted to contemporary healthcare requirements nor involved consumers in ascertaining environmental requirements. The issues found in the literature are addressed under five themes: the design of physical space, family needs, privacy considerations, the impact of technology, and patient safety.

Conclusion: There is a need for greater input into the design of healthcare spaces from those who use them, to incorporate dignified and expedient care delivery in the care of the person and to meet the needs of family.

Developing an approach to assess the influence of integrating disaster risk reduction practices into infrastructure reconstruction on socio-economic development

Purpose: Disasters provide physical, social, economic, political and environmental development windows of opportunity particularly through housing and infrastructure reconstruction. The reconstruction process should not be neglected due to the opportunistic nature of facilitating innovation in development. In this respect, post-disaster "infrastructure" reconstruction plays a critical role in development discourse and is often essential to sustain recovery after major disasters. However, reconstruction following a natural disaster is a complicated problem involving social, economic, cultural, environmental, psychological, and technological aspects. There are significant development benefits of well-developed "Disaster Risk Reduction (DRR) Strategies" and, for many reasons, the concept of DRR can be more easily promoted following a disaster. In this respect, a research study was conducted to investigate the effects of integrating DRR strategies into infrastructure reconstruction on enhancing the socio-economic development process from a qualitative stance. The purpose of this paper is to document part of this research study; it proposes an approach that can be used to assess the influence of the application of the DRR concept into infrastructure reconstruction on socio-economic development. Design/methodology/approach: The research methodology included a critical literature review. Findings: This paper suggests that the best way to assess the influence of integrating DRR strategies practices into infrastructure reconstruction on socio-economic development is to assess the level of impact that DRR strategies has on overcoming various factors that form vulnerabilities. Having assessed this, the next step is to assess the influence of overcoming the factors that form vulnerabilities on achieving performance targets of socio-economic development. Originality/value: This paper primarily presents a framework for the concept of socio-economic development and a modelled classification of DRR practices.