Characterization of microfluidic shear-dependent epithelial cell adhesion molecule immunocapture and enrichment of pancreatic cancer cells from blood cells with dielectrophoresis

Current microfluidic techniques for isolating circulating tumor cells (CTCs) from cancer patient blood are limited by low capture purity, and dielectrophoresis (DEP) has the potential to complement existing immunocapture techniques to improve capture performance. We present a hybrid DEP and immunocapture Hele-Shaw flow cell to characterize DEP''s effects on immunocapture of pancreatic cancer cells (Capan-1, PANC-1, and BxPC-3) and peripheral blood mononuclear cells (PBMCs) with an anti-EpCAM (epithelial cell adhesion molecule) antibody. By carefully specifying the applied electric field frequency, we demonstrate that pancreatic cancer cells are attracted to immunocapture surfaces by positive DEP whereas PBMCs are repelled by negative DEP. Using an exponential capture model to interpret our capture data, we show that immunocapture performance is dependent on the applied DEP force sign and magnitude, cell surface EpCAM expression level, and shear stress experienced by cells flowing in the capture device. Our work suggests that DEP can not only repel contaminating blood cells but also enhance capture of cancer cell populations that are less likely to be captured by traditional immunocapture methods. This combination of DEP and immunocapture techniques to potentially increase CTC capture purity can facilitate subsequent biological analyses of captured CTCs and research on cancer metastasis and drug therapies.     

An Experimental Comparison of a Conventional and a Project Centered Method of Teaching a College General Botany Course

Research on teacher behaviors that actively promote student intrinsic motivation to learn has been relatively scarce. In this article, 2 studies exploring the effects of teacher enthusiasm on both students' intrinsic motivation to learn and their pychological vitality are presented (Ryan & Frederick, 1997). In Study 1, a questionnaire including measures of intrinsic motivation, vitality, teacher enthusiasm, and numerous other positive teacher behaviors was administered to 93 college students. Among the teacher variables, enthusiasm was the most powerful unique predictor of students' intrinsic motivation and vitality. In Study 2, level of teacher enthusiasm (high vs. low) was manipulated in an experimental design with 60 college students. The students who received an enthusiastically delivered lecture subsequently reported greater intrinsic motivation regarding the lecture material and experienced higher levels of vitality. The authors speculate about possible mechanisms for and limitations to the positive motivational effects of teacher enthusiasm.     

Holding complexity and searching for meaning: Teaching as reflective practice

This paper explores differences between traditions in relation to teaching and learning. As a relative newcomer from the Anglo/American curriculum tradition, I seek to highlight the ways in which Central and Northern European tradition of Didaktik has offered a new dimension and fresh insights to the notion of reflective practice. In particular, the paper seeks to emphasize the significance of Klafki's notion of Didaktik analysis, with its focus on meaning and its aim to re-enact the rationale for subject matters. Against this background, teaching is seen as a moral and reflecting activity that is primarily concerned with a search for meaning.     

The permanent secretary as policy-maker,shaper, taker,sharer, and resister in education – reflections on Sir James Hamilton as a centralising outsider

Given that elevation to permanent secretary is widely recognised as the apotheosis of a career in the Whitehall bureaucracy, it is remarkable that so few have been the subject of sustained biographical research and that this key role remains largely un-theorised. As such, this paper reports on aspects of a longitudinal study which set out to examine, evaluate, and categorise to what extent, and how, permanent secretaries influence policy. Based on recorded interviews with those who held this office at the DES from 1976 to 2002, along with those they served and others, it argues that if the role of senior civil servants can be labelled ‘meta-political’, they do influence policy in significant ways. As such, it suggests that their praxis can be interrogated in terms of their activities as makers, shapers, takers, sharers, and resisters of policy in education. Focusing on the career of a committed centraliser, James Hamilton, it examines the contribution he made as permanent secretary to a variety of departmental policy initiatives including the pursuit of voucherisation and the case for a national school curriculum.     

Towards an uncertain politics of professionalism: teacher and nurse identities in flux

This paper is about the nature of contemporary professional identity. It looks at the ways in which ‘discursive dynamics’ come to re-write the professional teacher and nurse as split, plural and conflictual selves, as they seek to come to terms with a political impetus written through what the authors term an ‘economy of performance’ in uncertain conflict with various ‘ecologies of practice’. The teacher and nurse are thus located in a complicated nexus between policy, ideology and practice. Epistemologically, the paper offers a deconstruction of professional identities, and criticizes the reductive typologies and characterizations of current professionalism. Politically, it reaches towards a more nuanced account of professional identities, stressing the local, situated and indeterminable nature of professional practice, and the inescapable dimensions of trust, diversity and creativity.     

Implementing policy for homeless kids in schools: reassessing the micro and macro levels in the policy debate in Australia

This study suggests that the debate over the nature of policy is far from resolved. The extent to which the extremes of the debate about the role of the state in policy, about interpretations about power in policy process and about the differential nature of fine‐grained examinations of policy at the local level versus larger scale theorizing, affect interpretation are questioned. Based on a case study of the implementation of a policy dealing with homeless student in four Victorian, Australia, High schools, this paper suggests that the conceptualizations of the state and understanding the nature of power relations in policy process are more complex than any other authors have suggested. The analysis of the policy implementation process showed that whilst at certain times the power of the state appeared to be crucial and central, at other times the power of the state was decentred and significantly reduced, with power and control of policy being refocused at the school level.     

Finding an identity and meeting a standard: connecting the conflicting in teacher induction

This article has the apparently contradictory aims of describing a discourse of new teachers that is at odds with the policy‐derived competence‐based discourse of the professional standard for teachers, and of also seeking to find some points of connection that may help start a dialogue between policy and research. The experience of new teachers is conceptualised as personal stories of identity formation with a clear emotional‐relational dimension and a sense of self and intrinsic purpose in which others, especially colleagues and children, are central – themes not visible in the standard. The empirical context is that of new teachers in Scotland but the argument is supported through a wider literature that extends beyond the traditional limits of teacher education, drawing on, for example, notions of self‐identity, pure relationship and ontological security in the work of Giddens. Whether a more constructive dialogue can begin depends partly on the extent to which the formal standard can be expected to capture the complex, personal nature of the beginner’s experience, and partly on the possibility of research identifying particular areas of competence, such as understanding difference, that connect in some way to the standard.     

Core skills assessment to improve mathematical competency

Many engineering undergraduates begin third-level education with significant deficiencies in their core mathematical skills. Every year, in the Dublin Institute of Technology, a diagnostic test is given to incoming first-year students, consistently revealing problems in basic mathematics. It is difficult to motivate students to address these problems; instead, they struggle through their degree, carrying a serious handicap of poor core mathematical skills, as confirmed by exploratory testing of final year students. In order to improve these skills, a pilot project was set up in which a ‘module’ in core mathematics was developed. The course material was basic, but 90% or higher was required to pass. Students were allowed to repeat this module throughout the year by completing an automated examination on WebCT populated by a question bank. Subsequent to the success of this pilot with third-year mechanical engineering students, the project was extended to five different engineering programmes, across three different year-groups. Full results and analysis of this project are presented, including responses to interviews carried out with a selection of the students involved.     

Common elements of capstone projects in the world's top-ranked engineering universities

‘Capstone’ is a metaphor used to describe a final achievement that builds upon previous works and encapsulates them. Capstone projects are included in engineering curricula to integrate multi-disciplinary subjects and teach professional skills that are difficult to impart in a traditional lectured course. Since these projects serve to transition students into professional engineers, they have a direct impact on a university's industry reputation and ranking. Therefore, it is worthwhile to study the capstone programmes implemented at the world's top-ranked engineering universities to discover common elements which characterise them. In this paper, common elements of the capstone programmes implemented in mechanical and aerospace engineering undergraduate programmes in the world's top-ranked engineering universities are identified and analysed to determine established best practices. These practices can be modelled and applied to the pedagogy of engineering programmes at universities around the world to improve the development of professional skills of future graduates.