CommonKnowledge Copyright (c) 2013 Pacific University All rights reserved. http://commons.pacificu.edu Recent documents in CommonKnowledge en-us Thu, 23 May 2013 01:33:32 PDT 3600 A Comparison of Active and Passive 3D Television Technology and Their Practicality for Classroom Education Use http://commons.pacificu.edu/opt/5 http://commons.pacificu.edu/opt/5 Wed, 08 May 2013 14:10:14 PDT Stereoscopic 3D TVs convey depth perception to the viewer by delivering separately-filtered images to each eye that represent two slightly different perspectives. Currently two primary technologies are used in 3D televisions: active shutter systems and passive polarized systems. Active shutter systems use alternate frame sequencing to deliver a full-frame image to one eye at a time at a fast refresh rate. Passive polarized systems superimpose two half-frame left-eye and right-eye images at the same time through different polarizing filters. In this study, sixty subjects were recruited to compare their visual performance and subjective rating of two 3D televisions representing the two technologies.

Image quality for both 2D and 3D images were investigated by objectively measuring participant’s visual acuity and contrast sensitivity on each television. The 3D image was investigated further by objectively measuring stereoacuity, perceived versus intended depth perception, effect of viewing angles and a step-vergence task that measured the participant’s ability to swiftly diverge or converge to a new stimulus. A discomfort questionnaire was used to assess participant’s pre and post movie-viewing comfort. Subjective questionnaires were used to gather participant’s opinions on various image quality components, glasses preference, and overall television preference.

Objectively, the subjects had a lower measured contrast and acuity threshold in 2D on the active television, but they had a lower contrast threshold in 3D, as well as faster vergence reaction times on the passive television. With a single subject investigation, no difference between TVs was found for varying off-axis viewing angles, both horizontally and vertically, when comparing VA thresholds, contrast thresholds and stereoacuity at each angle. The passive television was subjectively preferred in all of the following ways: perceived image clarity, color, motion smoothness, overall immersion, perceived ghosting, less disruption from head tilting and viewing angles, longer predicted viewing time before discomfort, overall glasses preference and overall final television preference.

In conclusion, in this study, passive TV technology was a solid winner when it came to subject’s personal ratings, but only outperformed the active TV objectively with contrast and speed of vergence responses. When considering image quality, viewing comfort and room dimensions, subjects felt the passive TV outperformed the active TV in all three categories. With objective measures, passive statistically excelled at two traits in 3D mode and active statistically excelled at two traits in 2D mode for image quality, while no difference was found between televisions for viewing comfort. In addition, no variables were statistically different between TVs that would change the dimensions of a movie-viewing zone. It should be emphasized that the results are based on a relatively small sample size (57 subjects, most young female adults) and tested on specific display models. Investigation with a larger sample size and reaching to broader populations is required before reaching expansive conclusions. In addition, active and passive projector systems, could be a good option for classrooms that are able to afford the system. Future studies should compare the difference between 3D projector systems as well as any future glasses-free systems developed with a broader viewing range than the current available televisions.

]]> Leigh Gongaware In-House Mentorship http://commons.pacificu.edu/phrmfac/53 http://commons.pacificu.edu/phrmfac/53 Mon, 06 May 2013 09:35:49 PDT Reza Karimi An Interprofessional Care Approach at a Supported Living Center http://commons.pacificu.edu/hip/vol1/iss4/6 http://commons.pacificu.edu/hip/vol1/iss4/6 Fri, 03 May 2013 14:55:33 PDT The complex and comprehensive management of polypharmacy among individuals who reside in supported living centers requires an interprofessional approach that includes the collaborative efforts of disciplines such as medicine, pharmacy, nursing, and psychology. As a result of this collaboration, health care outcomes can be optimized, and the different disciplines can also become aware of the contributions that each department can make towards improving patients' quality of care through the reduction of unnecessary medication prescribing.

Note: This is the transcription of an interview between James Kundart, HIP Editor-in-Chief, and Abimbola Farinde. The audio recording of this interview is available below for download (3 parts).

]]> Abimbola Farinde Genetic Manipulation of Leishmania Parasites Facilitates the Exploration of the Polyamine Biosynthetic Pathway as a Potential Therapeutic Target http://commons.pacificu.edu/phrmfac/52 http://commons.pacificu.edu/phrmfac/52 Fri, 19 Apr 2013 11:29:47 PDT Parasites of the genus Leishmania cause a variety of devastating and often fatal diseases, ranging from cutaneous ulcerative lesions to fatal visceralizing infections that affect an estimated 12 million people worldwide. Unfortunately, vaccines are not available and the cturent arsenal of drugs used to treat leishmaniasis is far from ideal. Thus the need for new therapeutic targets and a better understanding of host-parasite interactions is urgent. One biochemical pathway that has been successfully exploited for the treatment of a related parasitic disease, African trypanosomiasis, is the polyamine biosynthetic pathway. In order to elucidate the polyamine biosynthetic pathway and to explore its potential as a therapeutic target in Leishmania, we have generated and characterized gene deletion mutants and polyamine enzyme overproducer strains. These studies revealed that the polyamine pathway in Leishmania is significantly different from that of the mammalian host and polyamines were found to be essential for parasite proliferation. Infectivity studies in macrophages and mice with gene deletion mutants revealed that at least two polyamine biosynthetic enzymes, ornithine decarboxylase and spermidine synthase, are necessary for Leishmania donovani to establish a successful infection. However, arginase gene deletion mutants of Leishmania mexicana are still capable of eliciting an infection, albeit at lower levels than wild type parasites. Ongoing studies address whether the disparities in infectivity are due to the loss of specific enzymes within the pathway or to differences between the two Leishmania species. Furthermore, the gene deletion mutants are useful tools to investigate the relative contribution of host and parasite polyamine biosynthetic enzymes in parasite infectivity. This chapter will summarize how genetic manipulations in Leishmania have advanced our understanding of the polyamine pathway and its role in host-parasite interactions.

]]> Sigrid C. Roberts Connecting with Curriculum [Library Publishing and Undergraduate Education] http://commons.pacificu.edu/libfac/22 http://commons.pacificu.edu/libfac/22 Wed, 17 Apr 2013 09:15:28 PDT Presentation from a panel session, Library Publishing and Undergraduate Education: Strategies for Collaboration, at the ACRL 2013 Conference, Indianapolis, IN.

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