Optics Commons^™

Altered Cholesterol Metabolism In Human Cancers Unraveled By Label-Free Spectroscopic Imaging, Shuhua Yue

Open Access Dissertations

Despite tremendous scientific achievements, cancer remains the second leading cause of death in the United States. Metabolic reprogramming has been increasingly recognized as a core hallmark of cancer. My dissertation work identified novel diagnostic markers and therapeutic targets for human cancers through the study of cholesterol in cancer cells.

Enabled by label-free Raman spectromicroscopy, we performed the first quantitative analysis of lipogenesis at single cell level in human patient cancerous tissues. Our imaging data revealed an unexpected, aberrant accumulation of esterified cholesterol in lipid droplets of high-grade prostate cancer and metastases, but not in normal prostate, benign prostatic hyperplasia, or …

Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections, and the effects of tissue processing. Both hand and thigh sections of human cadavers were analysed in their unprocessed and formalin fixed paraffin processed (FFPP) and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum, intermediate underlying epithelium and dermal layers for sections from both anatomical sites. The stratum corneum is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that …

Potential For High Resolution Microscintigraphy Using Polycapillary Optics, Patrick Richard Conlon

Legacy Theses & Dissertations (2009 - 2024)

Scintigraphy, also known as nuclear imaging, is the process of imaging an object that has been labeled with a radioactive material. A novel technique employing polycapillary optics for very high - resolution scintigraphy is presented. The small channel size and angular selectivity of polycapillary optics allow them to act as multiple-hole collimators and be used with high - resolution detectors. The ability of the optics to work with high resolution detectors allow the system to discriminate against scatter, thus negating the need for energy sensitive detectors, which are known to have poor resolution. Therefore the use of polycapillary optics presents …

Sensitive Fluorescence Detection Using A Camera From The Gaming Industry, Brian L. Van Hoozen Jr.

Lawrence University Honors Projects

The detection limit for fluorescence imaging has been improved by more than two orders of magnitude by a modulation technique that minimizes the influence of noise. Since most noise sources have a 1/f dependence, higher modulation frequencies result in less noise in the detected signal. Typical cameras used for imaging have frame rates of 50 or 100 hertz which is too low for substantial noise reduction. However, new time-of-flight cameras developed for the gaming industry have modulation frequencies of up to 20 MHz, allowing for a substantial reduction in noise in the detected signal. In this study, the improved detection …

The Effect Of Participating In Continuing Optometric Education: A Pilot Study, Claire E. Mcdonnell, Martina Crehan

Other

Purpose: To determine whether participation in two different post graduate optometry workshops resulted in a change in practice for the participants, in their subsequent practice.

Methods: 38 optometrists, who had attended a continuing professional development (CPD) workshop on punctal plugs and lacrimal syringing, were surveyed by email and telephone, between four and thirteen months post workshop, to ascertain if they had made a change to their practice. A second group of 32 optometrists, who had attended a continuing education and training (CET) workshop on binocular vision, were surveyed by email, telephone and postal mail between six and nine months post …

Characterization Of Optically Stimulated Luminescent Detectors In Photon & Proton Beams For Use In Anthropomorphic Phantoms, James R. Kerns

Dissertations and Theses (Open Access)

This study investigated characteristics of optically stimulated luminescent detectors (OSLDs) in protons, allowing comparison to thermoluminescent detectors, and to be implemented into the Radiological Physics Center’s (RPC) remote audit quality assurance program for protons, and for remote anthropomorphic phantom irradiations. The OSLDs used were aluminum oxide (Al2O3:C) nanoDots from Landauer, Inc. (Glenwood, Ill.) measuring 10x10x2 mm3. A square, 20(L)x20(W)x0.5(H) cm3 piece of solid water was fabricated with pockets to allow OSLDs and TLDs to be irradiated simultaneously and perpendicular to the beam. Irradiations were performed at 5cm depth in photons, and in the center of a 10 cm SOBP in …

Application Of X-Ray Diffraction To Material Analysis And Medical Imaging, Wei Zhou

Legacy Theses & Dissertations (2009 - 2024)

Powder diffraction is commonly used to determine the structures of both inorganic and organic materials. The angle and intensity of the diffraction (also called coherent scatter) peak depends on the nanostructure of the material. When no x-ray optic is used, the peak width broadens, and hence the resolution worsens, as the sample area is increased. However, a small sample area gives low diffracted signal intensity, particularly for thin films and for organic materials, which have low diffraction cross sections. X-ray optics can be used in x-ray powder diffraction to increase the diffraction intensity, thus decreasing exposure times. For a small …

Optical Properties Of Human Uterus At 630 Nm, Steen J. Madsen, Bruce J. Tromberg, Yona Tadir, Pius Wyss, Lars O. Svaasand, Richard C. Haskell

All HMC Faculty Publications and Research

The optical properties of normal and fibriotic human uteri were determined using frequency-domain and steady-state techniques .