202,504 research outputs found
Embedding blended learning in a university’s teaching culture: experiences and reflections
Blended learning, the combination of traditional face-to-face teaching methods with authentic on-line learning activities, has the potential to transform student learning experiences and outcomes. In spite of this advantage, university teachers often find it difficult to adopt new on-line techniques, in part because institutional practices are still geared to support more traditional approaches. This paper describes how a project, funded to support international collaboration to enhance learning and teaching in Geography, has allowed a university to explore models for change. It briefly examines the associated issues of sharing and repurposing resources; it reflects on the impact of the project on local strategy, and the importance of sustaining the collaborations and approaches to learning and teaching after the funding is completed
Panning for gold: designing pedagogically-inspired learning nuggets
Tools to support teachers and learning technologists in the creation of effective learning designs are currently in their infancy. This paper describes a metadata model, devised to assist in the conception and design of new learning activities, that has been developed, used and evaluated over a period of three years. The online tool that embodies this model was not originally intended to produce runtime executable code such as IMS-LD, but rather focussed on assisting teachers in the thought processes involved in selecting appropriate methods, tools, student activities and assessments to suit the required learning objectives. Subsequently, we have modified the RELOAD editor such that the output from our tool can be translated into IMS-LD. The contribution of this paper is the comparison of our data model with that of IMS-LD, and the analysis of how each can inform the other
Computation of order and volume fill rates for a base stock inventory control system with heterogeneous demand to investigate which customer class gets the best service
We consider a base stock inventory control system serving two customer classes whose demands are generated by two independent compound renewal processes. We show how to derive order and volume fill rates of each class. Based on assumptions about first order stochastic dominance we prove when one customer class will get the best service. That theoretical result is validated through a series of numerical experiments which also reveal that it is quite robust.Base stock policy; service measures; two customer classes; compound renewal processes
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Intelligent Flood Fill or: The Use of Edge Detection in Image Object Extraction
Content-Based Image Retrieval systems can often return poor results when attempting to match images with extraneous feature information such as complex backgrounds, shadows, or frames. As a solution, this project aimed to provide a semi-automatic object extraction tool, the ‘Intelligent Flood Fill’. This tool would also help users of graphics packages, who can find current object extraction tools inefficient. The solution implemented is based upon innovations and extensions to the floodfill technique, and is both accurate and efficient in itself, and compared to existing methods. The new algorithms presented allow extraction based on scribbles over the image which gather colour data, and/or a bounding box, outside of which the algorithm will try to revert to the last major colour change. An option for sequence extraction has also been implemented for use in VRML model creation. The architecture is flexible, so as to allow the control logic to be rewritten for another language or application as desired, and the user interface intuitive. Failures can occur when the foreground and background overlap in colour space, or when the image is low resolution or noisy. Extensions include making use of dedicated image loading libraries, and the implementation of a live wire boundary system for complex images
Comparison of image analysis software packages in the assessment of adhesion of microorganisms to mucosal epithelium using confocal laser scanning microscopy
We have compared current image analysis software packages in order to find the most useful one for assessing microbial adhesion and inhibition of adhesion to tissue sections. We have used organisms of different sizes, the bacterium Helicobacter pylori and the yeast Candida albicans. Adhesion of FITC-labelled H. pylori and C. albicans was assessed by confocal microscopy. Four different Image analysis software packages, NIH-Image, IP Lab, Image Pro+, and Metamorph, were compared for their ability to quantify adhesion of the two organisms and several quantification methods were devised for each package. For both organisms, the dynamic range that could be detected by the software packages was 1×106?1×109 cells/ml. Of the four software packages tested, our results showed that Metamorph software, using our ?Region of Interest? method, with the software's ?Standard Area Method? of counting, was the most suitable for quantifying adhesion of both organisms because of its unique ability to separate clumps of microbial cells. Moreover, fewer steps were required. By pre-incubating H. pylori with the glycoconjugate Lewis b-HSA, an inhibition of binding of 48.8% was achieved using 250 ?g/ml Lewis b-HSA. The method we have devised using Metamorph software, provides a simple, quick and accurate way of quantifying adhesion and inhibition of adhesion of microbial cells to the epithelial surface of tissue sections. The method can be applied to organisms ranging in size from small bacteria to larger yeast cells
Mitomycin C in highly myopic eyes - Author reply
Ophthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Hot-fill voor de afwas
This report presents an overview of possibilities and limitations of the hot-fill principle applied in washing machines and dish washing equipment. The study started with literature research, showing the washing performance of hot-fill washing machines to be generally poorer than the performance of cold-fill equipment. Moreover, washing machines specifically adapted to hot-fill have longer pay-back periods. For hot-fill dish washers no unequivocal measuring results relating to energy consumption and dish washing performance were available. That's why the study further focused on dish washers. A number of energy consumption measurements and washing performance tests at various operating modes have shown the greatest energy cost cuts to be attained in filling a standard dish washer with hot water. The washing and drying performance is not affected by hot-fill. From supplementary measurements it appeared that storage-type water heaters are most suitable for this application. With this type of appliance energy consumption is lowest. Dimensioning of the hot water piping is important. Only if the sizing is kept to a minimum, will there be any saving of primary energy, when running the 65 degrees C standard program. Application of hot-fill dish washers will contribute to a reduction of environmental acidification. Given the current use of the various washing programs in the Netherlands hot-fill will also help reduce CO2 emissions
Deep subcutaneous application of poly-L-lactic acid as a filler for facial lipoatrophy in HIV-infected patients
Introduction: Facial lipoatrophy is a crucial problem of HIV-infected patients undergoing highly active antiretroviral therapy (HAART). Poly-L-lactic acid (PLA), provided as New-Fill(R)/Sculptra(TM), is known as one possible treatment option. In 2004 PLA was approved by the FDA as Sculptra(TM) for the treatment of lipoatrophy of the face in HIV-infected patients. While the first trials demonstrated relevant efficacy, this was to some extent linked to unwanted effects. As the depth of injection was considered relevant in this context, the application modalities of the preparation were changed. The preparation was to be injected more deeply into subcutaneous tissue, after increased dilution. Material and Methods: To test this approach we performed a pilot study following the new recommendations in 14 patients. Results: While the efficacy turned out to be about the same, tolerability was markedly improved. The increase in facial dermal thickness was particularly obvious in those patients who had suffered from lipoatrophy for a comparatively small period of time. Conclusion: With the new recommendations to dilute PLA powder and to inject it into the deeper subcutaneous tissue nodule formation is a minor problem. However, good treatment results can only be achieved if lipoatrophy is not too intense; treatment intervals should be about 2 - 3 weeks. Copyright (C) 2005 S. Karger AG, Basel
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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