Analysis of a laminar-flow diffusional mixer for directed self-assembly of liposomes

The present work describes the operation and simulation of a microfluidic laminar-flow mixer. Diffusive mixing takes place between a core solution containing lipids in ethanol and a sheath solution containing aqueous buffer, leading to self assembly of liposomes. Present device architecture hydrodynamically focuses the lipid solution into a cylindrical core positioned at the center of a microfluidic channel of 125 × 125-μm² cross-section. Use of the device produces liposomes in the size range of 100–300 nm, with larger liposomes forming at greater ionic strength in the sheath solution and at lower lipid concentration in the core solution. Finite element simulations compute the concentration distributions of solutes at axial distances of greater than 100 channel widths. These simulations reduce computation time and enable computation at long axial distances by utilizing long hexahedral elements in the axial flow region and fine tetrahedral elements in the hydrodynamic focusing region. Present meshing technique is generally useful for simulation of long microfluidic channels and is fully implementable using comsol Multiphysics. Confocal microscopy provides experimental validation of the simulations using fluorescent solutions containing fluorescein or enhanced green fluorescent protein.     

Positive emotions: passionate scholarship and student transformation

This paper challenges the practical and conceptual understanding of the role of emotions in higher education from the twin perspectives of transition and transformation. Focusing on the neglected area of positive emotions, exploratory data reveal a rich, low-level milieu of undergraduate emotional awareness in students chiefly attributed to pedagogic actions, primarily extrinsically orientated, and pervasive throughout the learning experience. The data conceive positive affect as oppositional, principally ephemeral and linked to performative pedagogic endeavours of getting, knowing and doing. A cyclical social dynamic of reciprocity, generating positive feedback loops, is highlighted. Finally we inductively construct a tentative ‘emotion-transition framework’ to assist our understanding of positive emotion as a force for transformational change; our contention is that higher education might proactively craft pedagogic spaces so as to unite the feeling discourse, the thinking discourse (epistemological self) and the wider life-self (ontological) discourse.     

Content and Context of the Administrative Internship: How Mentoring and Sustained Activities Impact Preparation

As universities prepare educational leaders for twenty-first century schools, the quality and authenticity of the internship experience require both the strengths of university faculty and the expertise of practitioners to create authentic experiences that seek to bridge the theory-to-practice divide. One mechanism to achieve this is through quality mentorship by school- and central-office-based personnel during the internship experience. A central aspect of this professional relationship is the ability for the mentor to provide access to quality activities that will prepare the aspiring leader for his/her first administrative position. This exploratory study examined language utilized by interns in their time logs as well as information gleaned from preliminary surveys of both interns and mentors upon completion of their experience. Findings revealed the complexity of language analysis and revealed a need for understanding activities of interns and interactions with mentors in a contextual fashion.     

Contraction: implications for school leaders

Ackoff's circular structure has been successfully utilised to combine hierarchy and democracy in various industries. This paper argues that this structure is the most appropriate democratic structure for the internal governance of public schools. It concludes that a circularity of power relations between administrators and teachers would create genuinely empowering teacher participation, improve co‐ordination, foster teacher self‐actualisation and expressiveness, alleviate teacher shortages, help attract high quality persons to teaching careers, ensure appropriate (service oriented) teacher supervision, and increase the number of successful school improvement projects.     

Challenges to Institutionalizing Participatory Extension: The Case of Farmer Livestock Schools in Vietnam

Abstract

Purpose: The objective of this article is to analyze the introduction of participatory extension approaches (PEA) in the predominantly supply-driven, hierarchical Vietnamese extension system. Drawing on the case of the so-called Farmer Livestock School (FLS) concept, the authors investigate the potential and challenges of scaling up and out the FLS/PEA principles of participatory training methods, encompassing intensive and interactive training sessions, group-based sharing of experience, practical learning, and learning-by-doing processes.

Design/Methodology/Approach: The article is based on data collected and synthesized from 36 pilot communes from 2000 to 2007 and draws on the extensive insider experience of two of its authors during their work for a DANIDA-funded livestock project.

Findings: At the micro-scale and with external support, FLS has been a successful experiment of using participatory extension approaches in farmer training and extension in the livestock sector. Yet, possibilities of scaling up and institutionalizing FLS remain a challenge given the capacity and resource limitations and the resistance at various levels within the Vietnamese extension system.

Practical Implications: The starting point for successfully institutionalizing participatory extension approaches should be to assess the existing system's root problems and capacities and then gradually and systematically introduce institutional innovations rather than aiming at a complete overhaul of a system that may result in the creation of a parallel universe.

Originality/Value: The FLS project provided a unique opportunity to study the enabling and constraining factors of institutionalizing participatory extension approaches in a traditionally top-down oriented extension system beyond the immediate duration of an externally orchestrated project.