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A Wax

Publications and source records attributed to A Wax.

7 recordsLinked to original sources
PubMed2003

Instrumentation for multi-modal spectroscopic diagnosis of epithelial dysplasia.

Reflectance and fluorescence spectroscopies have shown great promise for early detection of epithelial dysplasia. We have developed a clinical reflectance spectrofluorimeter for multimodal spectroscopic diagnosis of epithelial dysplasia. This clinical instrument, the FastEEM, collects white light reflectance and fluorescence excitation-emission matrices (EEM's) within a fraction of a second. In this paper we describe the FastEEM instrumentation, designed for collection of multi-modal spectroscopic data. We illustrate its performance using tissue phantoms with well defined optical properties and biochemicals of known fluorescence properties. In addition, we discuss our plans to develop a system that combines a multi-spectral imaging device for wide area surveillance with this contact probe device.

Carcinoma↗
PubMed2000

Time-resolved phase-space distributions for light backscattered from a disordered medium.

We demonstrate time-resolved measurement of optical phase-space distributions as a new probe for investigating the propagation of light in disordered media. Phase-space techniques measure the joint transverse position and momentum distribution of the scattered light, and are sensitive to the spatially varying phase and amplitude of the field. Using this method we investigate light backscattered from a random medium. The measurements indicate that the weakly localized component is a phase conjugate of the incident light field. A new model of backscatter, based on Wigner phase-space distributions, elucidates the spatial and angular behavior of the localized and unlocalized components.

Biomedical Engineering↗
PubMed2000

Feasibility of field-based light scattering spectroscopy.

Light scattering spectroscopy (LSS) is a new technique capable of accurately measuring the features of nuclei and other cellular organelles in situ. We present the considerations required to implement and interpret field-based detection in LSS, where the scattered electric field is detected interferometrically, and demonstrate that the technique is experimentally feasible. A theoretical formalism for modeling field-based LSS signals based on Mie scattering is presented. Phase-front uniformity is shown to play an important and novel role. Results of heterodyne experiments with polystyrene microspheres that localize LSS signals to a region about 30 microns in axial extent are reported. In addition, differences between field-based LSS and the earlier intensity-based LSS are discussed.

Cell Nucleus↗
PubMed1998

Measurement of smoothed Wigner phase-space distributions for small-angle scattering in a turbid medium.

We study Wigner phase-space distributions W (x, p) in position (x) and momentum (p) for light undergoing multiple small-angle scattering in a turbid medium. Smoothed Wigner phase-space distributions are measured by using a heterodyne technique that achieves position and momentum resolution determined by the width and the diffraction angle of the local oscillator beam. The sample consists of 5.7-micron-radius polystyrene spheres suspended in a water-glycerol mixture. The momentum distribution of the transmitted light is found to contain a ballistic peak, a narrow diffractive pedestal, and a broad background. The narrow diffractive pedestal is found to decay more slowly than the ballistic peak as the concentration of scatterers is increased. The data are in excellent agreement with a simple theoretical model that explains the behavior of the narrow pedestal by including multiple diffractive scattering and treating large-angle scattering as a loss.

Light↗
PubMed1995

Two unusual presentations of müllerian adenosarcoma: case reports, literature review, and treatment considerations.

Müllerian adenosarcomas of the uterus usually present as pedunculated endometrial masses in postmenopausal women with vaginal bleeding. Extraendometrial variants (originating in the ovary, adnexa, or myometrium) are much less common, and they tend to present at a more advanced stage due to their location. The sarcomatous portion of müllerian adenosarcoma can vary from low grade to very high grade and the clinical behavior of the tumors can be indolent or aggressive. We present two cases, one of which originated in the adnexa and the other in an apparent focus of uterine adenomyosis. These cases illustrate the difficulty of correct diagnosis and treatment.

Adenosarcoma↗
PubMed1982

Cancer patient accessions into clinical trials: a pilot investigation into some patient and physician determinants of entry.

This study investigated the external validity (or generalizability of results) of randomized clinical trials in cancer. Tao ECOG lung cancer chemotherapy protocols active in the early 1970s were studied using a case-control design. All lung cancer patients of the four specified cell types resident in Monroe County during the ECOG study period were identified from the Rochester Regional Tumor Registry. All of the patients entered into either protocol ("ECOG cases") and a random sample of the nonprotocol cases were examined by medical records review. Thirty-seven percent of the nonprotocol cases were determined to have been eligible for either of the two ECOG protocols, but not entered ("eligible controls"). A comparison of the ECOG cases (n = 65) and the eligible controls (n = 109) revealed that (1) ECOG cases were more likely than eligible controls to have been diagnosed at a hospital which participated in the University of Rochester Cancer Center's medical oncology program; (2) ECOG cases were of higher occupational status than eligible controls; (3) duration from diagnosis to protocol entry for ECOG cases was longer than duration from diagnosis to earliest date of eligibility for eligible controls. The implications of these findings for the conduct of cancer clinical trials are discussed.

Aged↗