33,697 research outputs found
Glassy materials investigated for nuclear reactor applications
Studies determine the feasibility of preparing fuel-bearing glasses and glasses bearing neutron-absorbing materials for use as crystalline fuel and control rods for reactors. Properties investigated were devitrification resistance, urania solubility, and density
Low-Cost Motility Tracking System (LOCOMOTIS) for time-lapse microscopy applications and cell visualisation
This article has been made available through the Brunel Open Access Publishing Fund.Direct visualisation of cells for the purpose of studying their motility has typically required expensive microscopy equipment. However, recent advances in digital sensors mean that it is now possible to image cells for a fraction of the price of a standard microscope. Along with low-cost imaging there has also been a large increase in the availability of high quality, open-source analysis programs. In this study we describe the development and performance of an expandable cell motility system employing inexpensive, commercially available digital USB microscopes to image various cell types using time-lapse and perform tracking assays in proof-of-concept experiments. With this system we were able to measure and record three separate assays simultaneously on one personal computer using identical microscopes, and obtained tracking results comparable in quality to those from other studies that used standard, more expensive, equipment. The microscopes used in our system were capable of a maximum magnification of 413.6x. Although resolution was lower than that of a standard inverted microscope we found this difference to be indistinguishable at the magnification chosen for cell tracking experiments (206.8x). In preliminary cell culture experiments using our system, velocities (mean mm/min Ā± SE) of 0.81Ā±0.01 (Biomphalaria glabrata hemocytes on uncoated plates), 1.17Ā±0.004 (MDA-MB-231 breast cancer cells), 1.24Ā±0.006 (SC5 mouse Sertoli cells) and 2.21Ā±0.01 (B. glabrata hemocytes on Poly-L-Lysine coated plates), were measured and are consistent with previous reports. We believe that this system, coupled with open-source analysis software, demonstrates that higher throughput time-lapse imaging of cells for the purpose of studying motility can be an affordable option for all researchers. Ā© 2014 Lynch et al
Three-axis adjustable loading structure
A three axis adjustable loading structure for testing the movable surfaces of aircraft by applying pressure, is described. The device has three electric drives where the wall angle, horizontal position, and vertical position of the test device can be rapidly and accurately positioned
Scholarly collaboration across time zones
The barriers to global collaboration of yesteryear were, for example, country boundaries and time zones. Today however, in a world where communication is thriving on new technologies, these barriers have been overcome, not only by the technology itself, but also by the collaborators in a desire (and need) to extend knowledge, seize opportunities and build partnerships.
This chapter reports on one such collaboration: a case study where the focus is the writing of a scholarly article between authors from Australia, England and South Africa. The challenges of different time zones, academic calendars, and managing the collaboration are outlined in this chapter. Findings from the case study suggests that the key elements of success are related to the individuals and project management techniques, and not the technology per se. The constructivist learning theory as well as the e-Moderation model are supported by this work and thus extend their application to the academic writing process
Information technology team projects in higher education: an international viewpoint
It is common to find final or near final year undergraduate Information Technology students undertaking a substantial development project; a project where the students have the opportunity to be fully involved in the analysis, design, and development of an information technology service or product. This involvement has been catalyzed and prepared for during their previous studies where the students have been told and shown how to develop similar systems. It is the belief that only through this ārealā project do they get the chance to experience something similar to what is expected of them when they embark on their chosen profession; that is, as an information technology professional.
The high value of ānear real lifeā educational experience is recognized by many universities across the globe. The aim of this paper is to present examples from three countries - Australia, United Kingdom and South Africa, of the delivery of these team, capstone or industrial experience projects; their curricula and management processes. Academics from institutions in each of the countries share experiences, challenges and pitfalls encountered during the delivery of these information technology projects within their institutions. An overview of each institutionās strategies is provided and highlights specific issues such as the selection of projects, allocation of teams to projects, legal requirements, assessment methods, challenges and benefits.
The pedagogies presented here are not exhaustive; however, the three institutions do have in common the implementation of a combination of constructivism with a community of practice approach in delivering the project unit. The three universities recognize the need for industrial experience and learning of applied skills, and therefore make these projects a compulsory part of the curriculum. The projects tend to be real life business problems which are solved over a period of two semesters, and in the case of Cape Town it could be two consecutive years of two semesters each. These projects tend to involve practical development (for example databases and web sites). The process of project-to-team allocation is generally similar in all cases.
Despite their differences, team work related problems are quite similar in all three cases presented, and seem to appear as a result of team work complexity, and the number of stakeholders involved. The intention of this paper is not to propose solutions to these problems (as these would be context dependent), but to draw the attention to the main problem categories for similar schemes, these are;
ā¢ project selection,
ā¢ management of students,
ā¢ management of academic staff,
ā¢ student team motivation,
ā¢ equality and diversity,
ā¢ passengers, and
ā¢ assessment.
Furthermore, it is not the intention of the authors to portray one approach as better than another, however, the approaches are representative of how team projects are being delivered across the globe, and in particular, in the contributing institutions. It is hoped that the assimilation and dissemination of information regarding the various approaches presented will nurture further discussion, and open communication across the globe with the view to enhancing the teaching and learning experience of such projects
High-tip-speed fiber composite compressor blades: Vibration and strength analysis
An analytical procedure is described which couples composite mechanics computer codes with NASTRAN. This procedure was used to perform a detailed analysis of a high-tip-speed fiber composite compressor fan blade. The results indicate that the various vibration modes of this blade are highly coupled. Mechanical load ply stresses are well below the corresponding room temperature strengths. Lamination residual stresses are likely to cause transply cracks and interply delamination. Transply cracks and relaxation of root fixity decrease the vibrational frequencies whereas centrifugal stiffening increases them. Comparisons of results for various parameters are presented in tabular and graphical form
Analysis of stresses at the bore of a drilled ball operating in a high-speed bearing
Three-dimensional stress distributions were calculated for both a regular drilled ball with a stiffening web. The balls were 20.6 mm (0.8125 in.) in diameter and had a 12.6 mm (0.496 in.) diameter concentric hole. The stiffening web was 1.5 mm (0.06 in.) thick. The calculations showed that a large reversing tangential stress at the hole bore was reduced by one-half by the addition of the web
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