O efeito da exposição à luz visível e a limitação de oxigênio durante o crescimento micelial foi investigado na tolerância de conídios de dez fungos entomopatogênicos a: (A) radiação UV; (B) estresse osmótico causado pelo cloreto de potássio (KCl) e (C) estresse genotóxico provocado por 4-nitroquinoline-1-óxido (4-NQO). No primeiro experimento, foi avaliado o limiar de fotoativação de Metarhizium robertsii. Foram estudadas quatro intensidades de luz com 1, 3, 4 e 5 lumens, nas quais, foi avaliada a germinação e o aumento de tolerância ao estresse osmótico. No segundo experimento, foi analisada a influência da luz branca no aumento da tolerância à radiação UV, KCl, e 4-NQO em dez espécies de fungos entomopatogênicos. No terceiro experimento, foi avaliado a influência da luz branca, azul, verde e vermelha no aumento de tolerância à radiação UV e estresse osmótico em M. robertsii. No quarto experimento, foi avaliada a influência da limitação de oxigênio no aumento de tolerância à radiação UV, KCl, e 4-NQO em dez espécies de fungos entomopatogênicos. No quinto experimento, foi utilizado o isolado M. robertsii (ARSEF 2575), foi analisado a expressão dos genes provavelmente envolvidos na indução da tolerância ao estresse quando conídios são produzidos sob luz visível e limitação de oxigênio. No primeiro experimento, conídios produzidos sob a luz branca apresentaram maior tolerância ao estresse osmótico em comparação com os conídios produzidos no escuro. Não houve grande diferença de tolerância entre as intensitdades de luz testadas. No segundo experimento, a luz branca induziu o aumento de tolerância aos estresses em B. bassiana (KCl e 4NQO), M. brunneum (KCl e 4NQO), M. robertsii (UV e KCl), T. cylindrosporum (KCl), I. fumosorosea (UV), L. aphanocladii (KCl) e A. aleyrodis (KCl e 4NQO). No terceiro experimento, conídios produzidos sob a luz branca e azul, foram mais tolerantes à radiação UV e ao estresse osmótico, conídios crescidos sob a luz vermelha foram menos tolerantes. No quarto experimento, a hipoxia induziu o aumento de tolerância aos estresses em B. bassiana (UV, KCl e 4NQO), M. brunneum (UV, KCl e 4NQO), M. robertsii (UV, KCl), M. anisopliae (UV e KCl), T. inflatum (KCl) e A. aleyrodis (KCl e 4NQO). A anoxia induziu o aumento de tolerância ao estresse em seis isolados, B. bassiana (UV e 4NQO), M. brunneum (KCl), M. anisopliae (KCl e 4NQO), M. robertsii (UV e KCl), T. inflatum (KCl), A. aleyrodis (4NQO). O estresse nutritivo (MM) induziu o aumento de tolerância aos estresses em B. bassiana (UV, KCl e 4NQO), M. brunneum (UV e KCl), M. robertsii (UV e KCl) e M. anisopliae (UV e KCl), T. cylindrosporum (UV), I. fumosorosea (KCl), T. inflatum (UV) e S. lanosoniveum (KCl). No quinto experimento, os genes superexpressos foram: Mrhsp30 (MM, luz branca, luz azul, vermelha, luz verde, anoxia), Mrhsp101 (luz vermelh, a luz verde e hipoxia), Mr6-4 phr (MM, luz branca, luz azul), Mrsod2 (MM, luz vermelha), Mrtps (luz azul, vermelha, verde e hipóxia), Mrpr1 (luz verde). Neste estudo, a luz branca e limitação de oxigênio foram determinantes no aumento de tolerância aos estresses. / The effect of exposure of visible light and oxygen limitation during mycelial growth was investigated in the tolerance of conidia of ten entomopathogenic fungi to: (A) UV radiation; (B) osmotic stress caused by potassium chloride (KCl) and (C) genotoxic stress caused by 4-nitroquinoline 1-oxide (4NQO). In the first experiment, the photoactivation threshold of Metarhizium robertsii was evaluated. Four light intensities with 1, 3, 4 and 5 lumens were studied, where germination and increased tolerance to osmotic stress were evaluated. In the second experiment, the influence of white light without increasing the tolerance to UV, KCl, and 4-NQO in ten species of entomopathogenic fungi was analyzed. In the third experiment, the influence of white, blue, green and red light on the increase of tolerance to UV radiation and osmotic stress in M. robertsii was evaluated. In the fourth experiment, the influence of oxygen limitation on the increase of tolerance to UV, KCl, and 4-NQO in tem entomopathogenic fungi species were evaluated. In the fifth experiment, the M. robertsii isolate (ARSEF 2575) was used; an expression of the genes involved in the induction of stress tolerance was analyzed when conidia are produced under visible light and oxygen limitation. In the first experiment, conidia produced under white light presented greater tolerance to osmotic aesthetics in comparative eaters. There were no major differences in tolerance between tested light intensities. In the second experiment, white light induced increased stress tolerance in B. bassiana (KCl e 4NQO), M. brunneum (KCl e 4NQO), M. robertsii (UV e KCl), T. cylindrosporum (KCl), I. fumosorosea (UV), L. aphanocladii (KCl) e A. aleyrodis (KCl e 4NQO). In the third experiment, conidia produced under white and blue light were more tolerant to UV radiation and osmotic stress, conidia grown under the red light so tolerant. In the fourth experiment, hypoxia induced increased stress tolerance in B. bassiana (for UV, KCl e 4NQO), M. brunneum (UV, KCl e 4NQO), M. robertsii (UV, KCl), M. anisopliae (UV e KCl), T. inflatum (KCl) e A. aleyrodis (KCl e 4NQO). Anoxia induced higher tolerance in B. bassiana (for UV e 4NQO), M. brunneum (KCl), M. anisopliae (KCl e 4NQO), M. robertsii (UV e KCl), T. inflatum (KCl), A. aleyrodis (4NQO). The nutritive stress (MM) induced increased stress tolerance in B. bassiana (UV, KCl e 4NQO), M. brunneum (UV e KCl), M. robertsii (UV e KCl) e M. anisopliae (UV e KCl), T. cylindrosporum (UV), I. fumosorosea (KCl), T. inflatum (UV) e S. lanosoniveum (KCl). In the fifth experiment, the over-expressed genes were Mrhsp30 (MM, white light, blue light, red, green light, anoxia), Mrhsp101 (red light, green light and hypoxia), Mr6-4 phr (MM, white light, blue light), Mrsod2 (MM, red light), Mrtps (blue, red, green and hypoxia light), Mrpr1 (green light). In this study, white light and oxygen limitation were determinants of increased stress tolerance.

Computational modeling offers better insight into a wide range of bioelectrical and biomechanical problems with improved tools for the design of medical devices and the diagnosis of pathologies. Electromagnetic modeling at low and high frequencies is particularly necessary. Modeling electromagnetic, structural, thermal, and acoustic response of the human body to different internal and external stimuli is limited by the availability of numerically efficient computational human models. This study describes the development to date of a computational full-body human model - Visible Human Project (VHP) - Female Model. Its unique feature is full compatibility both with MATLAB and specialized FEM computational software packages such as ANSYS HFSS/Maxwell 3D. This study also describes progress made to date in using the newly developed tools for segmentation. A visualization tool is implemented within MATLAB and is based on customized version of the constrained 2D Delaunay triangulation method for intersecting objects. This thesis applies a VHP - Female Model to a specific application, transcranial Direct Current Stimulation (tDCS). Transcranial Direct Current Stimulation has been beneficial in the stimulation of cortical activity and treatment of neurological disorders in humans. The placement of electrodes, which is cephalic versus extracephalic montages, is studied for optimal targeting of currents for a given functional area. Given the difficulty of obtaining in vivo measurements of current density, modeling of conventional and alternative electrode montages via the FEM has been utilized to provide insight into the tDCS montage performance. An insight into future work and potential areas of research, such as study of bone quality have been presented too.

Approximately, two-thirds of earth's surface is covered by water. There is a growing interest from the military and commercial communities in having, an efficient, secure and high bandwidth underwater wireless communication (UWC) system for tactical underwater applications such as oceanography studies and offshore oil exploration. The existing acoustic and radio frequency (RF) technologies are severely limited in bandwidth because of the strong frequency dependent attenuation of sound in seawater and the high conductivity of seawater at radio frequencies, respectively. Recently, underwater wireless optical communication (UWOC) has been proposed as the best alternative or complementary solution to meet this challenge. Taking advantage of the low absorption window of seawater in blue-green (400-550 nm) regime of the electromagnetic spectrum, UWOC is expected to establish secure, efficient and high data rate communication links over short and moderate distances (< 100 m) for versatile applications such as underwater oil pipe inspection, remotely operated vehicle (ROV) and sensor networks. UWOC uses the latest gallium nitrite (GaN) visible light-emitting diode (LED) and laser diode (LD) transmitters. Although some research on LED lased UWOC is being conducted, both the military and academic 5 research communities are favoring the use of laser beams, which potentially could enhance the available bandwidth by up to three orders of magnitude. However, the underwater wireless channel is optically very challenging and difficult to predict. The propagation of laser beams in seawater is significantly affected by the harsh marine environments and suffers from severe attenuation which is a combined effect of absorption and scattering, optical turbulence, and multipath effects at high transmission rates. These limitations distort the intensity and phase structure of the optical beam leading to a decrease in signal-to-noise ratio (SNR) which ultimately degrades the performance of UWOC links by increasing the probability of error. In this dissertation, we seek to experimentally demonstrate the feasibility of short range (≤ 20 m) UWOC systems over various underwater channel water types using different modulation schemes as well as to model and describe the statistical properties of turbulence-induced fading in underwater wireless optical channels using laser beam intensity fluctuations measurements.

O efeito da exposição à luz visível e a limitação de oxigênio durante o crescimento micelial foi investigado na tolerância de conídios de dez fungos entomopatogênicos a: (A) radiação UV; (B) estresse osmótico causado pelo cloreto de potássio (KCl) e (C) estresse genotóxico provocado por 4-nitroquinoline-1-óxido (4-NQO). No primeiro experimento, foi avaliado o limiar de fotoativação de Metarhizium robertsii. Foram estudadas quatro intensidades de luz com 1, 3, 4 e 5 lumens, nas quais, foi avaliada a germinação e o aumento de tolerância ao estresse osmótico. No segundo experimento, foi analisada a influência da luz branca no aumento da tolerância à radiação UV, KCl, e 4-NQO em dez espécies de fungos entomopatogênicos. No terceiro experimento, foi avaliado a influência da luz branca, azul, verde e vermelha no aumento de tolerância à radiação UV e estresse osmótico em M. robertsii. No quarto experimento, foi avaliada a influência da limitação de oxigênio no aumento de tolerância à radiação UV, KCl, e 4-NQO em dez espécies de fungos entomopatogênicos. No quinto experimento, foi utilizado o isolado M. robertsii (ARSEF 2575), foi analisado a expressão dos genes provavelmente envolvidos na indução da tolerância ao estresse quando conídios são produzidos sob luz visível e limitação de oxigênio. No primeiro experimento, conídios produzidos sob a luz branca apresentaram maior tolerância ao estresse osmótico em comparação com os conídios produzidos no escuro. Não houve grande diferença de tolerância entre as intensitdades de luz testadas. No segundo experimento, a luz branca induziu o aumento de tolerância aos estresses em B. bassiana (KCl e 4NQO), M. brunneum (KCl e 4NQO), M. robertsii (UV e KCl), T. cylindrosporum (KCl), I. fumosorosea (UV), L. aphanocladii (KCl) e A. aleyrodis (KCl e 4NQO). No terceiro experimento, conídios produzidos sob a luz branca e azul, foram mais tolerantes à radiação UV e ao estresse osmótico, conídios crescidos sob a luz vermelha foram menos tolerantes. No quarto experimento, a hipoxia induziu o aumento de tolerância aos estresses em B. bassiana (UV, KCl e 4NQO), M. brunneum (UV, KCl e 4NQO), M. robertsii (UV, KCl), M. anisopliae (UV e KCl), T. inflatum (KCl) e A. aleyrodis (KCl e 4NQO). A anoxia induziu o aumento de tolerância ao estresse em seis isolados, B. bassiana (UV e 4NQO), M. brunneum (KCl), M. anisopliae (KCl e 4NQO), M. robertsii (UV e KCl), T. inflatum (KCl), A. aleyrodis (4NQO). O estresse nutritivo (MM) induziu o aumento de tolerância aos estresses em B. bassiana (UV, KCl e 4NQO), M. brunneum (UV e KCl), M. robertsii (UV e KCl) e M. anisopliae (UV e KCl), T. cylindrosporum (UV), I. fumosorosea (KCl), T. inflatum (UV) e S. lanosoniveum (KCl). No quinto experimento, os genes superexpressos foram: Mrhsp30 (MM, luz branca, luz azul, vermelha, luz verde, anoxia), Mrhsp101 (luz vermelh, a luz verde e hipoxia), Mr6-4 phr (MM, luz branca, luz azul), Mrsod2 (MM, luz vermelha), Mrtps (luz azul, vermelha, verde e hipóxia), Mrpr1 (luz verde). Neste estudo, a luz branca e limitação de oxigênio foram determinantes no aumento de tolerância aos estresses. / The effect of exposure of visible light and oxygen limitation during mycelial growth was investigated in the tolerance of conidia of ten entomopathogenic fungi to: (A) UV radiation; (B) osmotic stress caused by potassium chloride (KCl) and (C) genotoxic stress caused by 4-nitroquinoline 1-oxide (4NQO). In the first experiment, the photoactivation threshold of Metarhizium robertsii was evaluated. Four light intensities with 1, 3, 4 and 5 lumens were studied, where germination and increased tolerance to osmotic stress were evaluated. In the second experiment, the influence of white light without increasing the tolerance to UV, KCl, and 4-NQO in ten species of entomopathogenic fungi was analyzed. In the third experiment, the influence of white, blue, green and red light on the increase of tolerance to UV radiation and osmotic stress in M. robertsii was evaluated. In the fourth experiment, the influence of oxygen limitation on the increase of tolerance to UV, KCl, and 4-NQO in tem entomopathogenic fungi species were evaluated. In the fifth experiment, the M. robertsii isolate (ARSEF 2575) was used; an expression of the genes involved in the induction of stress tolerance was analyzed when conidia are produced under visible light and oxygen limitation. In the first experiment, conidia produced under white light presented greater tolerance to osmotic aesthetics in comparative eaters. There were no major differences in tolerance between tested light intensities. In the second experiment, white light induced increased stress tolerance in B. bassiana (KCl e 4NQO), M. brunneum (KCl e 4NQO), M. robertsii (UV e KCl), T. cylindrosporum (KCl), I. fumosorosea (UV), L. aphanocladii (KCl) e A. aleyrodis (KCl e 4NQO). In the third experiment, conidia produced under white and blue light were more tolerant to UV radiation and osmotic stress, conidia grown under the red light so tolerant. In the fourth experiment, hypoxia induced increased stress tolerance in B. bassiana (for UV, KCl e 4NQO), M. brunneum (UV, KCl e 4NQO), M. robertsii (UV, KCl), M. anisopliae (UV e KCl), T. inflatum (KCl) e A. aleyrodis (KCl e 4NQO). Anoxia induced higher tolerance in B. bassiana (for UV e 4NQO), M. brunneum (KCl), M. anisopliae (KCl e 4NQO), M. robertsii (UV e KCl), T. inflatum (KCl), A. aleyrodis (4NQO). The nutritive stress (MM) induced increased stress tolerance in B. bassiana (UV, KCl e 4NQO), M. brunneum (UV e KCl), M. robertsii (UV e KCl) e M. anisopliae (UV e KCl), T. cylindrosporum (UV), I. fumosorosea (KCl), T. inflatum (UV) e S. lanosoniveum (KCl). In the fifth experiment, the over-expressed genes were Mrhsp30 (MM, white light, blue light, red, green light, anoxia), Mrhsp101 (red light, green light and hypoxia), Mr6-4 phr (MM, white light, blue light), Mrsod2 (MM, red light), Mrtps (blue, red, green and hypoxia light), Mrpr1 (green light). In this study, white light and oxygen limitation were determinants of increased stress tolerance.

Le présent travail interroge l’œuvre de Goffredo Parise (Vicenza, 1929 – Treviso, 1986) à partir du primat qu’il accorde à la vue dans chacun de ses écrits. Une recherche des causes au fondement d’une telle poétique ainsi que des implications qui en découlent a ainsi été menée dans un cadre d’interprétation dépassant les frontières purement littéraires au profit d’instruments méthodologiques empruntés à la philosophie (Maurice Merleau-Ponty, en ce qui concerne les liens avec la phénoménologie, et François Jullien, pour ce qui est du rapport à l’Orient), à l’anthropologie visuelle et à la critique d’art (Georges Didi-Huberman). Cette étude s’est développée selon deux axes principaux : d’une part, l’analogie entre la réflexion philosophique et la poétique de l’auteur, qui a montré la validité d’une relecture de l’œuvre de Parise à travers le prisme du primat de la perception ; d’autre part, les affinités qu’entretient l’écriture de Parise avec la pratique picturale, qui ont, une fois de plus, prouvé à quel point la production de l’auteur ne peut être contenue dans des frontières strictement littéraires mais exige le recours continuel à des instruments interprétatifs issus d’autres champs de recherche. / This research focuses on the work of Goffredo Parise (Vicenza, 1929 – Treviso, 1986) seen under the perspective of the primacy of the visual element, which can be traced in every text he has ever written. Drawing on Maurice Merleau-Ponty’s phenomenology, François Jullien’s thinking and Georges Didi-Huberman’s visual anthropology, the thesis aims to trace the origins of Parise’s poetics and its relationships with philosophy and visual arts. The first strand of the research deals with the intersections between Parise’s work and the philosophy of perception, while the second one investigates the similarities between Parise’s poetics and painting. This leads to the conclusion that Parise’s work requires broader instruments of analysis than traditional literary critique.

Made available in DSpace on 2016-04-27T17:26:51Z (GMT). No. of bitstreams: 1 Bruno Loureiro Conte.pdf: 597433 bytes, checksum: 474791994388813765e9eb9230745941 (MD5) Previous issue date: 2010-11-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / It is widely known that Parmenides Poem, which is considered a fundamental work in Greek philosophical thought, presents a plurality of mythical elements, and that its clarification constitutes an issue to the interpreters. This research is an investigation of the historical and philosophical meaning of mythos and logos in the Poem, considering the work in its cultural contexts. Our analysis begins by bringing to the foreground the presence of mythos, understood in its original sense of authorized way of speaking, pointing out its interweaving with logos, in such a manner that without the former the argument of the latter would remain incomprehensible. On the other hand, we aim to determine the specificity of logos in Parmenides: it shows up as a reflexive, refutative logos, but not, as some interpreters have sustained, a strict demonstration . Having established this point, Parmenides work shows itself as productive of a plurality of mythical assemblages, appropriating images of the traditional inspired poet, of initiation in cults of mystery, of divinity figures and of the Archaic Lyric conception of human existence. Furthermore, the Poem deploys itself in multiple discursive configurations: narration, argument, oracular speaking. In accordance to that, we introduce an interpretative hypothesis associating the Goddess speech in the Poem to a particular kind of oracle, similar to that of the mantic healer. Such associations or assemblages, nonetheless, are not simple reproductions of aspects already present in Greek culture: they are, as a matter of fact, subverted in the direction of the philosophically instituted radical reflection, which collects signals from visible and invisible, leading to thinking / Como é bem sabido, o poema de Parmênides, considerado uma das obras fundamentais do pensamento filosófico grego, apresenta uma pluralidade de elementos míticos, seu esclarecimento constituindo um problema para os intérpretes. Trata-se, neste trabalho, de investigar o significado histórico-filosófico do mythos e do logos no poema, a partir da inserção da obra em seus contextos culturais. Nossa análise inicia-se destacando a presença do mythos, entendido em seu sentido original de maneira autorizada de falar, mostrando-o de tal modo entrelaçado ao logos que o argumento , sem ele, sequer seria compreensível. De outro lado, procuramos determinar a especificidade do logos de Parmênides: trata-se de um logos reflexivo, refutativo , mas não, como pretendem alguns intérpretes, de uma estrita demonstração . Estabelecido esse ponto, surge a obra de Parmênides como produtora de agenciamentos míticos diversos, apropriando-se das imagens do poeta tradicional inspirado, da iniciação nos cultos de mistérios, de figuras de divindades e da concepção da existência humana presente na Lírica arcaica, efetuando-se o poema em múltiplas configurações discursivas (narrativa, argumento, fala oracular). Nesse sentido, introduzimos a hipótese interpretativa da associação da fala da deusa no poema a um tipo específico de oráculo, similar ao do médico-adivinho. Tais associações ou agenciamentos, todavia, não se revelam como simples reproduções de aspectos presentes na cultura grega: eles são mesmo subvertidos em direção à instauração filosófica de uma reflexão radical, que recolhe sinais do visível e do invisível, conduzindo ao pensar

Titanium dioxide(TiO2) is a stable, effective and well-known photocatalyst for degradation of pollutants. However, its practical applications are limited due to the need for energy higher than 3.2 eV, or a wavelength lower than 390 nm (high frequency waves, ultraviolet and above) hindering its ability to effectively work in the visible light region (about 400 nm to 700 nm). Nitrogen-doped TiO2 (N-TiO2) has garnered some attention as a photocatalyst as it appears to work even in the visible light region. This could allow the utilization of a larger part of the solar spectrum. This thesis presents the results of photocatalytic degradation of methylene blue (MB) carried out under simulated visible light by using TiO2 and N-TiO2(doped in the lab) to evaluate and compare their efficiencies under similar conditions.

Immigrants to Canada report better health status than the Canadian-born population when they first arrive in Canada, a phenomenon called the Healthy Immigrant Effect. However, by the fourth year after immigration, immigrants report a health status that is worse than that of the Canadian-born population. Visible minority immigrant women report the largest deterioration in health. The purpose of this qualitative study was to explore the lived experiences of visible minority immigrant women with encounters with the Canadian healthcare system to examine the multiplicative impact of gender, ethnicity, and immigration on their health. This phenomenological study, guided by Crenshaw's feminist intersectionality framework, explored the perspectives of a purposive sample of 8 immigrant women in Ottawa, Canada, about their encounters with the healthcare system. Data were collected through individual interviews. These data were inductively coded and subjected to thematic analysis following the process outlined by Smith et al. for interpretative phenomenological analysis. Key findings of the study revealed that immigrant women define health more holistically and have expectations of the encounters with healthcare that are not met due to barriers that impact them accessing healthcare services, experiencing healthcare services, and following the recommended options. The positive social change implications of this study include recommendations for public health to consider immigration and racism as determinants of health; and for Health Canada to undertake system-level lines of inquiry to shed light on the ways structural discrimination and racism have had an impact on immigrant women's social and health trajectory.

The use of virtual reality (VR) for visualization can revolutionize medical training by simulating real world medical training procedures through intuitive and engaging user interface. Existing virtual reality based visualization systems for human anatomy are based on 3D surface and volumetric models and simulative systems based on model libraries. The visual impact as well as facilitation for learning are inadequate in such systems. This thesis research is aimed at eliminating such inadequacies by developing a non-immersive virtual reality system framework for storage, access and navigation of real human cadaveric data. Based on this framework, a real time software system called virtual cadaver navigation system (VCNS) is developed, that can be used as an aid for teaching human anatomy. The hardware components of the system include, a mannequin, an examination probe similar to a medical ultrasound probe, and a personal computer. The examination probe is moved over the mannequin to obtain the virtual tomographic slice from the real cadaveric3-D volume data. A 3-D binary space partitioning tree structure is defined to organize the entire volumetric data, by subdividing it into small blocks of predefined size, called as bricks that are assigned a unique address for identification. As the examination probe is moved over the mannequin, the set of bricks intersecting the corresponding tomographic slice are determined by traversing the tree structure, and only, the selected bricks are accessed from the main memory and brought into the texture memory on the graphics accelerator card for visualization. The texture memory in the graphics card and the main memory are divided into slots of size, that is a multiple of the brick size, and a tagging scheme that relates the brick addresses, texture memory slots, and the main memory blocks is developed. Based on spatial, temporal and sequential locality of reference, only the currently required bricks as well as some of the neighboring bricks are loaded from the main memory into the texture memory, in order to maintain the highest frame rates required forreal time visualization. The above framework consisting of the data organization and the access mechanism are critical in terms of achieving the interactive frame rates required for real-time visualization. The input data to the system consists of non-segmented voxel data, and the data segmented and labelled based on tissue classification. The software system includes a labeling tool, in order to display the specific tissue information at the the location of the mouse cursor. This facility is useful in both teaching anatomy and self learning. Thus, the proposed VCNS system supports efficient navigation through the human body for learning anatomy and provides the knowledge of spatial locations and the interrelationship among the various organs of the body. A prototype software system has been developed, which is capable of achieving a throughput of 30 frames per second and has been tested with a 18-Gigabyte human cadaveric data obtained from the National Library of Medicine, on a personal computer with 64 Megabytes of texture memory and 512 Megabytes of main memory.

Particle analysis using multiwavelength UV-visible spectroscopy provides the potential for extracting quantitative red blood cell information, such as hemoglobin concentration, cell size, and cell count. However, if there is a significant presence of hypochromism as a result of the concentrated hemoglobin (physiological value of 33%), successful quantification of red cell values would require a correction. Hypochromism has been traditionally defined as a decrease in absorption relative to the values expected from the Beer-Lambert Law due to electronic interactions of chromophores residing in close proximity of one another. This phenomenon has been suggested to be present in macroscopic systems composed of strong chromophores such as nucleic acids, chlorophyll, and hemoglobin. The study presented in this dissertation examines the presence of hypochromism in red blood cells as a part of a larger goal to qualitatively and quantatively characterize red blood cells using multiwavelength UV-visible spectroscopy. The strategy of the study was three-fold: 1) to determine the instrumental configuration that would provide the most complete information in the acquired spectra, 2) to develop an experimental model system in which the hemoglobin content in red blood cells could be modified to various concentrations, and 3) to implement an interpretation model based on light scattering theory (which accounts for both the scattering and absorption components of the optical density spectrum) to provide quantitative information for the experimental system. By this process, hypochromicity was redefined into two categories with molecular hypochromicity representing the traditional definition and macroscopic hypochromicity being an attenuation of the absorption component due to a scattering-related effect. Successful simulations of experimental red cell spectra containing various amounts of hemoglobin were obtained using the theoretical model. Furthermore, successful quantitative interpretation of the red blood cell spectra was achieved in the context of corpuscular hemoglobin concentration, corpuscular volume, and cell count solely by accounting for the scattering and absorption effects of the particle, indicating that molecular hypochromicity was insignificant in this macroscopic system.