871 research outputs found
Monoamine oxidase-A modulates apoptotic cell death induced by staurosporine in human neuroblastoma cells
Monoamine oxidases (MAOs) are mitochondrial enzymes which control the levels of neurotransmitters in the brain and dietary amines in peripheral tissues via oxidative deamination. MAO has also been implicated in cell signalling. In this study, we describe the MAO-A isoform as functional in apoptosis induced by staurosporine (STS) in human dopaminergic neuroblastoma cells (SH-SY5Y). Increased levels of MAO-A activity were induced by STS, accompanied by increased MAO-A protein and activation of the initiator of the intrinsic pathway, caspase 9, and the executioner caspase 3. MAO-A mRNA levels were unaffected by STS, suggesting that changes in MAO-A protein are due to post-transcriptional events. Two unrelated MAO-A inhibitors reduced caspase activation. STS treatment resulted in sustained activation of the mitogen-activated protein kinase pathway enzymes extracellular regulated kinase, c-jun terminal kinase and p38, and depletion of the anti-apoptotic protein Bcl-2. These changes were significantly reversed by MAO inhibition. Production of reactive oxygen species was increased following STS exposure, which was blocked by both MAO inhibition and the antioxidant N-acetylcysteine. Therefore our data provide evidence that MAO-A, through its production of reactive oxygen species as a by-product of its catalytic activity on the mitochondrial surface, is recruited by the cell to enhance apoptotic signalling
Moebius strip enterprises and expertise in the creative industries: new challenges for lifelong learning?
The paper argues that the emergence of a new mode of production â co-configuration is generating new modes of expertise that EU policies for lifelong learning are not designed to support professionals to develop. It maintains that this change can be seen most clearly when we analyse Small and Medium Size (SMEs) enterprises in the creative industries. Drawing on concepts from Political Economy - âMoebius strip enterprise/expertiseâ and Cultural Historical Activity Theory - project-objectâ and the âspace of reasonsâ, the paper highlights conceptually and through a case study of an SME in the creative industries what is distinctive about the new modes of expertise, before moving on to reconceptualise expertise and learning and to consider the implications of this reconceptualisation for EU policies for lifelong learning. The paper concludes that the new challenge for LLL is to support the development of new forms expertise that are difficult to credentialise, yet, are central to the wider European goal of realising a knowledge economy
âOne door closes, a next door opens up somewhereâ: The learning of one Olympic synchronised swimmer
Although training in sport is necessary to reach Olympic status, a conditioned body is not the only outcome. Athletes also learn how to be Olympians. This learning involves taking on certain ways of acting, thinking and valuing. Such learning has implications beyond competition, as athletes eventually retire from elite sport and devote their time to other activities. This paper examines processes of learning and transition using the case of Amelia, a former Olympic synchronised swimmer. Through two in-depth interviews, empirical material was generated which focused on the learning that took place during this athleteâs career and after, during her transition to paid employment. A cultural view of learning was used as the theoretical frame to understand the athleteâs experiences. Our reading suggests that the athlete learned in various ways to be productive. Some of these ways of being were useful after retirement; others were less compatible. In fact, Amelia used a two-year period after retirement to reconstruct herself. Key to her eventual successful transition was to distance herself from the sport and to critically reflect upon her sporting experiences. We thus recommend that those involved with high-performance athletes foster a more balanced perspective that acknowledges and promotes ways of being beyond athletic involvement
Learning strategies used by apprentices in flexible delivery
Using a stimulated recall technique, eight apprentices were interviewed to identify the detailed learning strategies they used while constructing knowledge from flexible learning packages designed to develop workplace skills. The research shows that in their use of metacognitive, cognitive and social/affective learning strategies the apprentices in the sample made greatest use of those strategies that assisted them to construct knowledge as it was structured and presented by the learning package or by their instructors, trainers or supervisors. Little use was made of strategies that would indicate self-directed learning, working outside the structure provided, or learning independently of a sociocultural and hands-on context comprising their peers and their instructors. At the level of detail of learning strategies these results provide support for the larger scale quantitative research that has been previously conducted with apprentice learning preferences. <br /
Defining a self-evaluation digital literacy framework for secondary educators: the DigiLit Leicester project
Despite the growing interest in digital literacy within educational policy, guidance for secondary educators in terms of how digital literacy translates into the classroom is lacking. As a result, many teachers feel ill-prepared to support their learners in using technology effectively. The DigiLit Leicester project created an infrastructure for holistic, integrated change, by supporting staff development in the area of digital literacy for secondary school teachers and teaching support staff. The purpose of this article is to demonstrate how the critique of existing digital literacy frameworks enabled a self-evaluation framework for practitioners to be developed. Crucially, this framework enables a co-operative, partnership approach to be taken to pedagogic innovation. Moreover, it enables social and ethical issues to underpin a focus on teacher-agency and radical collegiality inside the domain of digital literacy. Thus, the authors argue that the shared development framework constitutes a new model for implementing digital literacy aimed at transforming the provision of secondary education across a city
Estimation of nitrogen budgets for contrasting catchments at the landscape scale
A comprehensive assessment of nitrogen (N) flows at the landscape scale is fundamental to understand spatial interactions in the N cascade and to inform the development of locally optimised N management strategies. To explore these interactions, complete N budgets were estimated for two contrasting hydrological catchments (dominated by agricultural grassland vs. semi-natural peat-dominated moorland), forming part of an intensively studied landscape in southern Scotland. Local scale atmospheric dispersion modelling and detailed farm and field inventories provided high resolution estimations of input fluxes. Direct agricultural inputs (i.e. grazing excreta, N<sub>2</sub> fixation, organic and synthetic fertiliser) accounted for most of the catchment N inputs, representing 82% in the grassland and 62% in the moorland catchment, while atmospheric deposition made a significant contribution, particularly in the moorland catchment, contributing 38% of the N inputs. The estimated catchment N budgets highlighted areas of key uncertainty, particularly N<sub>2</sub> exchange and stream N export. The resulting N balances suggest that the study catchments have a limited capacity to store N within soils, vegetation and groundwater. The "catchment N retention", i.e. the amount of N which is either stored within the catchment or lost through atmospheric emissions, was estimated to be 13% of the net anthropogenic input in the moorland and 61% in the grassland catchment. These values contrast with regional scale estimates: Catchment retentions of net anthropogenic input estimated within Europe at the regional scale range from 50% to 90%, with an average of 82% (Billen et al., 2011). This study emphasises the need for detailed budget analyses to identify the N status of European landscapes
Formality and informality in the summative assessment of motor vehicle apprentices: a case study
This article explores the interaction of formal and informal attributes of competenceâbased assessment. Specifically, it presents evidence from a small qualitative case study of summative assessment practices for competenceâbased qualifications within apprenticeships in the motor industry in England. The data are analysed through applying an adaptation of a framework for exploring the interplay of formality and informality in learning. This analysis reveals informal mentoring as a significant element which influences not only the process of assessment, but also its outcomes. We offer different possible interpretations of the data and their analysis, and conclude that, whichever interpretation is adopted, there appears to be a need for greater capacityâbuilding for assessors at a local level. This could acknowledge a more holistic role for assessors; recognise the importance of assessorsâ informal practices in the formal retention and achievement of apprentices; and enhance awareness of inequalities that may be reinforced by both informal and formal attributes of assessment practices
Learners and their workplaces: towards a strategic model of flexible delivery of training in the workplace
Although the flexible delivery of training in the workplace has become a favoured policy position for training authorities in both Britain and Australia, this article reviews research that indicates neither learners nor their workplaces are well prepared. Drawing on the author\u27s own research and that from the broader literature, the article develops a model for the preparation of learners and workplaces for flexible delivery of training. Deriving from the proposed model, the article suggests a wide range of strategies that may be used in preparing learners and workplaces for successful engagement with the flexible delivery of training. <br /
Abyssal deposit-feeding rates consistent with the metabolic theory of ecology
The Metabolic Theory of Ecology (MTE) posits that metabolic rate controls ecological processes, such as the rate of resource uptake, from the individualâ to the ecosystemâscale. Metabolic rate has been found empirically to be an exponential function of whole organism body mass. We test a fundamental assumption of MTE, whether resource uptake scales to metabolism, by examining detritivores accessing a single common resource pool, an ideal study case. We used an existing empirical model of ingestion for aquatic deposit feeders adjusted for temperature to test whether ingestion by abyssal deposit feeders conforms to MTEâpredicted feeding rates. We estimated the sediment depositâfeeding rates of large invertebrates from two abyssal study sites using timeâlapse photography, and related those rates to body mass, environmental temperature, and sediment organic matter content using this framework. Ingestion was significantly related to individual wet mass, with a massâscaling coefficient of 0.81, with 95% confidence intervals that encompass the MTEâpredicted value of 0.75, and the same pattern determined in other aquatic systems. Our results also provide insight into the potential mechanism through which this fundamental assumption operates. After temperature correction, both deepâ and shallowâwater taxa might be summarized into a single massâscaled ingestion rate
Personal epistemologies and disciplinarity in the workplace: implications for international students in higher education
Workplace experiences for international students undertaking higher education programs are important aspects of their university experience. This is because many of the programs in which they are enrolled are directed towards particular occupations. Nevertheless, these workplace experiences can be both engaging and daunting for all, but perhaps no more so than for international students, who may be unfamiliar with Australian workplace mores and practices, and therefore less able to understand and negotiate with them than their domestic counterparts. Not only do international students have to become familiar with the requirements of their selected profession but also need to understand and negotiate unfamiliar cultural environments. These students often have to engage in complex and demanding learning processes when engaging in work placements, perhaps more so than their domestic peers. Because of these discipline-based and workplace environmental challenges, it is necessary for these students and their mentors or supervisors to try and effectively mediate their participation and learning in the work placements. If all of those involved in work placements are aware of these factors, then the experiences and outcomes should potentially be more beneficial for all parties (i.e., students, supervisors, university staff, and workplaces). These issues are explored in this chapter through the notions of disciplinarity, which attends to the epistemological nuances of particular study or knowledge areas and how students develop skills as disciplinary professionals. With a focus on international students, the elaborations of these issues are explored through consideration of interculturalisation and how both the experiences and experiencing of international students impacts upon the success of their work placements. Using these concepts as explanatory bases stands to permit the illumination and elaboration of the complexity of factors and processes occurring as these students learn about, and participate in, their selected professional discipline and the cultural environment of its practice
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