Gravity spun polycaprolactone fibers for applications in vascular tissue engineering:proliferation and function of human vascular endothelial cells

Poly(ε-caprolactone) (PCL) fibers produced by wet spinning from solutions in acetone under low-shear (gravity-flow) conditions resulted in fiber strength of 8 MPa and stiffness of 0.08 Gpa. Cold drawing to an extension of 500% resulted in an increase in fiber strength to 43 MPa and stiffness to 0.3 GPa. The growth rate of human umbilical vein endothelial cells (HUVECs) (seeded at a density of 5 × 104 cells/mL) on as-spun fibers was consistently lower than that measured on tissue culture plastic (TCP) beyond day 2. Cell proliferation was similar on gelatin-coated fibers and TCP over 7 days and higher by a factor of 1.9 on 500% cold-drawn PCL fibers relative to TCP up to 4 days. Cell growth on PCL fibers exceeded that on Dacron monofilament by at least a factor of 3.7 at 9 days. Scanning electron microscopy revealed formation of a cell layer on samples of cold-drawn and gelatin-coated fibers after 24 hours in culture. Similar levels of ICAM-1 expression by HUVECs attached to PCL fibers and TCP were measured using RT-PCR and flow cytometry, indicative of low levels of immune activation. Retention of a specific function of HUVECs attached to PCL fibers was demonstrated by measuring their immune response to lipopolysaccharide. Levels of ICAM-1 expression increased by approximately 11% in cells attached to PCL fibers and TCP. The high fiber compliance, favorable endothelial cell proliferation rates, and retention of an important immune response of attached HUVECS support the use of gravity spun PCL fibers for three-dimensional scaffold production in vascular tissue engineering. © Mary Ann Liebert, Inc.

Engaging tutors in using e-repositories for learning and teaching

Universities which set up online repositories for the management of learning and teaching resources commonly find that uptake is poor. Tutors are often reluctant to upload their materials to e-repositories, even though the same tutors are happy to upload resources to the virtual learning environment (e.g. Blackboard, Moodle, Sakai) and happy to upload their research papers to the university’s research publications repository. The paper reviews this phenomenon and suggests constructive ways in which tutors can be encouraged to engage with an e-repository. The authors have recently completed a major project “Developing Repositories at Worcester” which is part of a group of similar projects in the UK. The paper includes the feedback and the lessons learned from these projects, based on the publications and reports they have produced. They cover ways of embedding repository use into institutional working practice, and give examples of different types of repository designed to meet the needs of those using different kinds of learning and teaching resources. As well as this specific experience, the authors summarise some of the main findings from UK publications, in particular the December 2008 report of Joint Information Systems Committee: Good intentions: improving the evidence base in support of sharing learning materials and Online Innovation in Higher Education, Ron Cooke’s report to a UK government initiative on the future of Higher Education. The issues covered include the development of Web 2.0 style repositories rather than conventionally structured ones, the use of tags rather than metadata, the open resources initiative, the best use for conventional repositories, links to virtual learning environments, and the processes for the management and support of repositories within universities. In summary the paper presents an optimistic, constructive view of how to embed the use of e-repositories into the working practices of university tutors. Equally, the authors are aware of the considerable difficulties in making progress and are realistic about what can be achieved. The paper uses evidence and experience drawn from those working in this field to suggest a strategic vision in which the management of e-learning resources is productive, efficient and meets the needs of both tutors and their students.

Applications of data envelopment analysis in education

Non-parametric methods for efficiency evaluation were designed to analyse industries comprising multi-input multi-output producers and lacking data on market prices. Education is a typical example. In this chapter, we review applications of DEA in secondary and tertiary education, focusing on the opportunities that this offers for benchmarking at institutional level. At secondary level, we investigate also the disaggregation of efficiency measures into pupil-level and school-level effects. For higher education, while many analyses concern overall institutional efficiency, we examine also studies that take a more disaggregated approach, centred either around the performance of specific functional areas or that of individual employees.