A generalized noise variance analysis model and its application to the characterization of 1/f noise

We present a novel generalized model for the analysis of noise with a known spectral density. This model is particularly appropriate for the analysis of noise with a 1/f^a distribution in a homodyne interferometer. The noise model reveals that, for α>1, 1/f^a noise significantly impacts the homodyne signal-to-noise ratio (SNR) for integration times that near a characteristic time, beyond which the SNR will no longer significantly improve with increasing integration time. We experimentally verify our theoretical findings with a set of experiments employing a quadrature homodyne optical coherence tomography (OCT) system, finding good agreement. The characteristic integration time is measured to be approximately 2 ms for our system. Additionally, we find that the 1/f noise characteristics, including the exponent, α, as well as the characteristic integration time, are system and photodetector dependent

A Thesis Towards Development of an Occupational Therapy Game System for Stroke Patients

Persons who have suffered from stroke participate in occupational therapy to help recover occupational functionality, but therapy is expensive and maximal recovery often depends on repetitive, tedious exercises to be done by patients both in therapy sessions and on their own. Often patients do not have the resources or motivation to complete the treatment required to give them the best results. This thesis is presented as part of a larger project in which we aim to enable occupational therapists to use the Looking Glass programming environment to create computer games for their patients that can be played inexpensively and effectively, both inside and outside of therapy sessions. Looking Glass will allow for occupational therapists with little or no programming background to write customized games for their patients. Through using Wii remotes and webcams to track movement and translate it to a computer game, this solution has the potential to provide a more engaging and interesting way for patients to correctly do repetitive movements without needing constant therapist supervision or expensive and complicated equipment. It also can provide highly customizable and adjustable game settings to accommodate for the wide range of impairments that can result from stroke. This thesis presents a study of the needs of occupational therapists and stroke patients who compose the user base of the project and implications for the design, the development of a webcam color tracking system to be used for movement tracking in games, and an application to be used by therapists to assign specific, patient-tailored calibrations and game levels as part of treatments and to track and organize improvement statistics. These are all key components required for the successful development of the overall project

SNR enhancement through phase dependent signal reconstruction algorithms for phase separated interferometric signals

We report several signal reconstruction algorithms for processing phase separated homodyne interferometric signals. Methods that take advantage of the phase of the signal are experimentally shown to achieve a signal-to-noise ratio (SNR) improvement of up to 5 dB over commonly used algorithms. To begin, we present a derivation of the SNR resulting from five image reconstruction algorithms in the context of a 3x3 fiber-coupler based homodyne optical coherence tomography (OCT) system, and clearly show the improvement in SNR associated with phase-based algorithms. Finally, we experimentally verify this improvement and demonstrate the enhancement in contrast and improved image quality afforded by these algorithms through homodyne OCT imaging of a Xenopus laevis tadpole. These algorithms can be generally applied in signal extraction processing where multiple phase separated measurements are available

Public Health Humanitarian Responses to Natural Disasters

The pressure of climate change, environmental degradation, and urbanisation, as well as the widening of socio- economic disparities have rendered the global population increasingly vulnerable to the impact of natural disasters. With a primary focus on medical and public health humanitarian response to disasters, Public Health Humanitarian Responses to Natural Disasters provides a timely critical analysis of public health responses to natural disasters. Using a number of case studies and examples of innovative disaster response measures developed by international agencies and stakeholders, this book illustrates how theoretical understanding of public health issues can be practically applied in the context of humanitarian relief response. Starting with an introduction to public health principles within the context of medical and public health disaster and humanitarian response, the book goes on to explore key trends, threats and challenges in contemporary disaster medical response. This book provides a comprehensive overview of an emergent discipline and offers a unique multidisciplinary perspective across a range of relevant topics including the concepts of disaster preparedness and resilience, and key challenges in human health needs for the twenty-first century. This book will be of interest to students of public health, disaster and emergency medicine and development studies, as well as to development and medical practitioners working within NGOs, development agencies, health authorities and public administration

Double the Vocation, Double the Awe: An Examination of Vocational Awe in Music Librarianship

Building upon Ettarh’s call to dismantle vocational awe in librarianship, this article outlines the shared components of Western libraries and Western music that lay the groundwork for vocational awe in each of these institutions and explores the ways in which vocational awe uniquely manifests for workers in the interdisciplinary field of music librarianship. The article explores the narrative of music’s goodness, disciplinary training, and manifestations of vocational awe as they appear in the institutional cultures of practice of music and librarianship: inability to develop work-life balance, job creep, low morale, and inequitable compensation. In naming this phenomenon as it is situated within music and music librarianship, we critically examine how it may affect our own narratives and values. We seek to empower those in music library work to become mindful of and address the presence and influence of vocational awe at individual and institutional levels

Turning Tissues Transparent by Optical Phase Conjugation

We recently implemented a digital optical phase conjugation mirror by combining a spatial light modulator and a digital holography system. This system provides us with additional flexibility in modifying the scattered wavefront for TSOPC transmission experiments. These results are discussed in detail in this presentation

Pump-probe optical coherence tomography using indocyanine green as a contrast agent

Use of indocyanine green (ICG), an FDA-approved dye, in a pump-probe scheme for optical coherence tomography (OCT) is reported. Aqueous solutions of ICG are not stable, i.e., the dye degrades over time especially in the presence of light. Addition of protein such as bovine serum albumin (BSA) stabilizes the ICG; however, when exposed to high intensity illumination, the dye still degrades. Moreover, the photodegradation is permanent and occurs swiftly if the illumination band corresponds to the ICG absorption peak. The permanence of the photobleached state illustrates that ICG photobleaching phenomenon has great potential to achieve contrast in OCT. ICG solutions with 50 micromolar concentration were prepared in water, 1% BSA, and 0.8% agarose to study the dynamics of the dye for different illumination intensity levels. In addition, different molar concentrations of ICG in water were studied for fixed illumination intensity. In each case, probability of photobleaching, defined as the ratio of the total photobleached ICG molecules to the total photons absorbed by the ground-state molecules, is evaluated to characterize the photobleaching phenomenon in ICG. We also demonstrate ICG-based pump-probe MCOCT imaging by mapping the distribution of ICG in a stage 54 Xenopus laevis

Patient and practitioner satisfaction with tele-dermatology including Australia’s indigenous population: A systematic review of the literature

AbstractBackgroundAustralia’s health disparity, combined with evolving technologies, has evoked increasing interest and funding in health services that could address inequities. One such emerging service is tele-medicine.ObjectiveThe purpose of this report is to discuss and evaluate the current literature regarding patient and practitioner satisfaction with tele-medicine, and more specifically tele-dermatology.MethodsWe searched for literature relevant to tele-dermatology use among Australia’s indigenous population. We synthesized the literature in our report and identified elements of tele-dermatology not yet researched.ResultsMost significantly, all available research is currently based on descriptive studies and there is no validated tool to assess the efficacy of tele-dermatology.LimitationsNo published research currently exists on the use of tele-dermatology among Australia’s indigenous population.ConclusionA review of the literature shows that tele-dermatology is considered a valuable service, particularly to patients living in rural areas who might not otherwise have access to specialist care