This study examined the effects of household fabric softeners on the thermal comfort and flammability of 100% cotton and 100% polyester fabrics after repeated laundering. Two fabric properties related to thermal comfort, water vapor transmission and air permeability, were examined. A 3 X 2 X 3 experimental design (i.e., 18 experimental cells) was developed to conduct the research. Three independent variables were selected: fabric softener treatments (i.e., rinse cycle softener, dryer sheet softener, no softener), fabric types (i.e., 100% cotton, 100% polyester), and number of laundering cycles (i.e., 1, 15, 25 cycles). Three dependent variables were tested: water vapor transmission, air permeability, and flammability. The test fabrics were purchased from Testfabrics, Inc. To examine the influence of the independent variables and their interactions on each dependent variable, two-way or three-way Analysis of Variance (ANOVA) tests were used to analyze the data. Results in this study showed that both the rinse cycle softener and the dryer sheet softener significantly decreased the water vapor transmission of test specimens to a similar degree. The rinse cycle softener decreased the air permeability of test specimens most and was followed by the dryer sheet softener. The rinse cycle softener increased the flammability of both cotton and polyester fabrics, but the dryer sheet softener had no significant effect on the flammability of both fabric types. Statistical analysis also indicated that the interactions were significant among the independent variables on water vapor transmission, air permeability, and flammability of the test specimens. For example, the rinse cycle softener significantly decreased the water vapor transmission and air permeability of cotton fabric but had no effect on polyester fabric. The dryer sheet softener also decreased the water vapor transmission of cotton fabric but had no effect on polyester fabric, and it had no effect on the air permeability of both cotton and polyester fabrics. In addition, the air permeability of cotton specimens treated with the rinse cycle softener continuously reduced after repeated laundering, but that of polyester fabrics treated with the rinse cycle softener only reduced after 15 laundering cycles and showed no continuous decrease when laundering cycles increased. When the influence of fabric softener treatments on flammability was examined, the results showed that the more the specimens were laundered with the rinse cycle softener, the greater the flammability of the test specimens. However, the dryer sheet softener did not have a significant effect on the flammability of the test fabrics even after repeated laundering. For the polyester fabric, all specimens treated with the dryer sheet softener or no softener passed the standard of children's sleepwear even after 25 laundering cycles, but those treated with the rinse cycle softener did not pass the standard. In conclusion, fabric softener treatment had a significant influence on the thermal comfort (i.e., water vapor transmission and air permeability) and flammability of 100% cotton and 100% polyester fabrics after repeated laundering cycles and the effects were significantly different among the three independent variables (i.e., fabric softener treatments, fabric types, and number of laundering cycles). The applications of these results were also discussed. / Master of Science

Yes / Current drugs against human African trypanosomiasis (HAT) suffer from several serious drawbacks. The search for novel, effective, brain permeable, safe, and inexpensive antitrypanosomal compounds is therefore an urgent need. We have recently reported that the 4-aminoquinoline derivative huprine Y, developed in our group as an anticholinesterasic agent, exhibits a submicromolar potency against Trypanosoma brucei and that its homo- and hetero-dimerization can result in to up to three-fold increased potency and selectivity. As an alternative strategy towards more potent smaller molecule anti-HAT agents, we have explored the introduction of ω-cyanoalkyl, ω-aminoalkyl, or ω-guanidinoalkyl chains at the primary amino group of huprine or the simplified 4-aminoquinoline analogue tacrine. Here, we describe the evaluation of a small in-house library and a second generation of newly synthesized derivatives, which has led to the identification of 13 side chain modified 4-aminoquinoline derivatives with submicromolar potencies against T. brucei. Among these compounds, the guanidinononyltacrine analogue 15e exhibits a 5-fold increased antitrypanosomal potency, 10-fold increased selectivity, and 100-fold decreased anticholinesterasic activity relative to the parent huprine Y. Its biological profile, lower molecular weight relative to dimeric compounds, reduced lipophilicity, and ease of synthesis, make it an interesting anti-HAT lead, amenable to further optimization to eliminate its remaining anticholinesterasic activity. / Wellcome Trust

Yes / A composite silicone skin adhesive material was designed to improve its water vapor permeability to offer advantages to wearer comfort compared to existing skin adhesive dressings available (including perforated silicone and hydrocolloid products). The chemical and mechanical properties of this novel dressing were analyzed to show that it has a high creep compliance, offering anisotropic elasticity that is likely to place less stress on the skin. A participant study was carried out in which 31 participants wore a novel silicone skin adhesive (Sil2) and a hydrocolloid competitor and were monitored for physiological response to the dressings. Trans-epidermal water loss (TEWL) was measured pre- and postwear to determine impairment of skin barrier function. Sil2 exhibited a higher vapor permeability than the hydrocolloid dressings during wear. Peel strength measurements and dye counter staining of the removed dressings showed that the hydrocolloid had a higher adhesion to the participants’ skin, resulting in a greater removal of proteins from the stratum corneum and a higher pain rating from participants on removal. Once the dressings were removed, TEWL of the participants skin beneath the Sil2 was close to normal in comparison to the hydrocolloid dressings that showed an increase in skin TEWL, indicating that the skin had been highly occluded. Analysis of the skin immediately after removal showed a higher incidence of erythema following application of hydrocolloid dressings (>60%) compared to Sil2, ( / T.S. received partial funding to study skin adhesive materials from a Medical Research Council Confidence in Concept grant obtained by John Bridgeman at the University of Bradford (MC_PC_19030). Initial formulation and characterization work benchmarking the Sil2 material was funded in part by Trio Healthcare Ltd., who have had no role in the analysis or interpretation of the data presented. All data was obtained independently by staff at the University of Bradford. We also wish to thank the Royal Society of Chemistry for funding Edward Dyson’s position as a research technician via a Research Enablement Grant (E21-8346952505).

This study has resulted in the discovery of an exact method for the theoretical formulation of the effects of intrinsic damping where the attenuation coefficient, a(v), is an arbitrary function of the frequency, v. Absorption-dispersion pairs are computed using numerical Hilbert transformation; approximate analytical expressions that require the selection of arbitrary constants and cutoff frequencies are no longer necessary. For constant Q, the dispersive body wave velocity, p(v), is found to be p(v) = (p(v_N)/(1+(1/2Q H(-v)/v)) where H denotes numerical Hilbert transformation, p(v) is the phase velocity at the frequency v, and p(v_N) is the phase velocity at Nyquist. From (1) it is possible to estimate Q in the time domain by measuring the amount of increase, ΔW, of the wavelet breadth after a traveltime, Q=(2Δ𝛕)/(𝝅ΔW) The inverse problem, i.e., the determination of Q and velocity is also investigated using singular value decomposition (SVD). The sparse matrices encountered in the acquisition of conventional reflection seismology data result in a system of linear equations of the form AX = B, with A the design matrix, X the solution vector, and B the data vector. The system of normal equations is AᵀAX = AᵀB where the least-squares estimate of X = X = V(1/S)UᵀB and the SVD of A is A = USVᵀ. A technique to improve the sparsity pattern prior to decomposition is described. From an application of equation (2) using reference reflections from shallower reflectors, crystalline rocks in South Carolina over the depth interval from about 5 km to 10 km yield values of Qin the range Q = 250 - 300. Non-standard recording geometries ( "Q-spreads") and vibroseis recording procedures are suggested to minimize matrix sparseness and increase the usable frequency bandwidth between zero and Nyquist. The direct detection of body wave dispersion by conventional vibroseis techniques may be useful to distinguish between those crustal volumes that are potentially seismogenic and those that are not. Such differences may be due to variations in fracture density and therefore water content in the crust. / Ph. D.

This research focuses on how the structure of modified interfaces influence the behavior of the interface. Two groups of dialkyl sulfides are prepared and studied: a purely hydrocarbon dialkyl sulfide with the structure CH₃(CH₂)₁₇S(CH₂)_nCH₃, where n=7, 9, and 17, and a carboxylic acid containing dialkyl sulfide with the structure CH3₃(CH₂)₁₇S(CH₂)_mCOOH, where m=7, 10, and 15. The structure and the permeability of these monolayers are characterized by <i>ex situ</i> and <i>in situ</i> FTIR, contact angle measurements, and electrochemistry. It is found that the two groups of dialkyl sulfides have different surface structures and different monolayer-solution interfacial behaviors. The presence of a polar group, such as -COOH, within the monolayer structure is found to increase the charge transfer properties of the modified electrode by influencing the interfacial structure. The structure and permeability of monolayers prepared from 15-mercaptopentadecanoic acid, 16-mercaptohexadecanoic acid, and their corresponding ethyl esters are also studied. Infrared spectroscopy and electrochemical permeability measurements indicate that the ester monolayers are ordered and have few differences in their structural and physical properties. Monolayers prepared from 15-mercaptopentadecanoic acid and 16-mercaptohexadecanoic acid, however, are structurally and physically different from the esters and each other. The IR and contact angle results indicate that hydrogen bonding interactions between the terminal groups of the monolayers influence the structural organization and physical properties of the monolayer. The extent of the hydrogen bonding interactions within the ω-mercaptoalkanoic acid monolayers appear to be related to the structure of the interface, suggesting that the orientation of the terminal functional group influences its ability to interact within the monolayer. / Master of Science

Electroporation-based treatments are motivated by the response of biological membranes to high- intensity pulsed electric fields. These fields rearrange the membrane structure to enhance the membrane's diffusive permeability, or the degree to which a membrane allows molecules to diffuse through it, is impacted by the structure, composition, and environment in which the cell resides. Tracer molecules have been developed that are unable to pass through intact cell membranes yet enter permeabilized cells. This dissertation investigates the hypothesis that the flow of such molecules may be used to quantify the effects of the electrical stimulus and environmental conditions leading to membrane electroporation. Specifically, a series of electrical pulses that alternates between positive and negative pulses permeabilizes cells more symmetrically than a longer pulse with the same total on-time. However, the magnitude of this symmetric entry decreases for the shorter alternating pulses. Furthermore, a method for quantitatively measuring the permeability of the cell membrane was proposed and validated. From data near the electroporation threshold, the response of cells varies widely in the manner in which cells become permeabilized. This method is applied to study the transient cell membrane permeability induced by electroporation and is used to demonstrate that the cell membrane remains permeable beyond 30 min following treatment. To analyze these experimental findings in the context of physical mechanisms, computational models of molecular uptake were developed to simulate electroporation. The results of these simulations indicate that the cell's local environment during electroporation facilitates the degree of molecular uptake. We use these models to predict how manipulating both the environment of cells during electroporation affects the induced membrane permeability. These experimental and computational results provide evidence that supports the hypothesis of this dissertation and provide a foundation for future investigation and simulation of membrane electroporation. / PHD / Electroporation is a biophysical process in which intense electric fields permeabilize bilayer membranes. The degree to which a membrane allows molecules to diffuse through it is called its diffusive permeability, and is impacted by the structure, composition, and environment in which the cell resides. This dissertation investigates the hypothesis that the flow of molecules into cells through their membranes may be used to quantitatively study the effects of the electrical stimulus and environmental conditions leading to membrane disruption. Here, I demonstrate that the cellular response to pulsed electric fields is affected by the waveform of the applied electrical stimulus. Specifically, a series of electrical pulses that alternates between positive and negative pulses permeabilizes cells more symmetrically than a longer pulse with the same total energized time. However, the total molecular uptake decreases for the shorter alternating pulses over the longer pulse. A method for quantitatively measuring the permeability of the cell membrane using a fluorescent tracer molecule is also developed and validated. This method is applied to show how cell membrane permeability changes following electroporation. To analyze these findings, computational models of molecular flow through the cell membrane are developed. These simulations indicate that the cell’s surrounding environment during electroporation dramatically impacts the degree of molecular uptake. We use these models to predict how manipulating both the environment of cells during electroporation affects the induced membrane permeability. These experimental and computational results provide a foundation for future investigation and simulation of membrane electroporation.

A large percentage of oil and gas reservoirs in the most productive regions such as the Middle East, South America, and Southeast Asia are naturally fractured reservoirs (NFR). The major difference between conventional reservoirs and naturally fractured reservoirs is the discontinuity in media in fractured reservoir due to tectonic activities. These discontinuities cause remarkable difficulties in describing the petrophysical structures and the flow of fluids in the fractured reservoirs. Predicting fluid flow behavior in naturally fractured reservoirs is a challenging area in petroleum engineering. Two classes of models used to describe flow and transport phenomena in fracture reservoirs are discrete and continuum (i.e. dual porosity) models. The discrete model is appealing from a modeling point of view, but the huge computational demand and burden of porting the fractures into the computational grid are its shortcomings. The affect of natural fractures on the permeability anisotropy can be determined by considering distribution and orientation of fractures. Representative fracture permeability, which is a crucial step in the reservoir simulation study, must be calculated based on fracture characteristics. The diagonal representation of permeability, which is customarily used in a dual porosity model, is valid only for the cases where fractures are parallel to one of the principal axes. This assumption cannot adequately describe flow characteristics where there is variation in fracture spacing, length, and orientation. To overcome this shortcoming, the principle of the full permeability tensor in the discrete fracture network can be incorporated into the dual porosity model. Hence, the dual porosity model can retain the real fracture system characteristics. This study was designed to develop a novel approach to integrate dual porosity model and full permeability tensor representation in fractures. A fully implicit, parallel, compositional chemical dual porosity simulator for modeling naturally fractured reservoirs has been developed. The model is capable of simulating large-scale chemical flooding processes. Accurate representation of the fluid exchange between the matrix and fracture and precise representation of the fracture system as an equivalent porous media are the key parameters in utilizing of dual porosity models. The matrix blocks are discretized into both rectangular rings and vertical layers to offer a better resolution of transient flow. The developed model was successfully verified against a chemical flooding simulator called UTCHEM. Results show excellent agreements for a variety of flooding processes. The developed dual porosity model has further been improved by implementing a full permeability tensor representation of fractures. The full permeability feature in the fracture system of a dual porosity model adequately captures the system directionality and heterogeneity. At the same time, the powerful dual porosity concept is inherited. The implementation has been verified by studying water and chemical flooding in cylindrical and spherical reservoirs. It has also been verified against ECLIPSE and FracMan commercial simulators. This study leads to a conclusion that the full permeability tensor representation is essential to accurately simulate fluid flow in heterogeneous and anisotropic fracture systems. / text

This dissertation is divided up into two parts, each examining a distinct theme. The rst part of our work concerns itself with open quantum systems and the relaxation phenomena arising from the repeated application of an interaction Hamiltonian on systems composed of quantum harmonic oscillators. For the second part of our work, we shift gears and investigate the wave propagation in left-handed media, or materials with simultaneously negative electric permeability and magnetic permeability . Each of these two parts is complete within its own context. In the rst part of this dissertation, we introduce a relaxation-generating model which we use to study the process by which quantum correlations are created when an interaction Hamiltonian is repeatedly applied to bipartite harmonic oscillator systems for some characteristic time interval . The two important time scales which enter our results are discussed in detail. We show that the relaxation time obtained by the application of this repeated interaction scheme is proportional to both the strength of interaction and to the characteristic time interval . Through discussing the implications of our model, we show that, for the case where the oscillator frequencies are equal, the initial Maxwell-Boltzmann distributions of the uncoupled parts evolve to a new Maxwell-Boltzmann distribution through a series of transient Maxwell-Boltzmann distributions, or quasi-stationary, non-equilibrium states. We further analyze the case in which the two oscillator frequencies are unequal and show how the application of the same model leads to a non-thermal steady state. The calculations are exact and the results are obtained through an iterative process, without using perturbation theory. In the second part of this dissertation, we examine the response of a plane wave incident on a at surface of a left-handed material, a medium characterized by simultaneously negative electric permittivity and magnetic permeability . We do this by solving Maxwell's equations explicitly. In the literature up to date, it has been assumed that negative refractive materials are necessarily frequency dispersive. We propose an alternative to this assumption by suggesting that the requirement of positive energy density can be relaxed, and discuss the implications of such a proposal. More speci cally, we show that once negative energy solutions are accepted, the requirement for frequency dispersion is no longer needed. We further argue that, for the purposes of discussing left-handed materials, the use of group velocity as the physically signi cant quantity is misleading, and suggest that any discussion involving it should be carefully reconsidered. / text

Este trabalho tem por finalidade o estudo da permeabilidade da madeira, com ênfase nas espécies de florestas plantadas do gênero de Pinus elliotti, Eucalyptus grandis e Eucalyptus citriodora. Com a sua determinação, avalia-se o quanto uma dada espécie de madeira é permeável a preservativos (tratamentos químicos) e o quanto ela é permeável a aplicação de adesivos estruturais (confecção de peças estruturais em Madeira Laminada Colada MLC). A avaliação da permeabilidade é um fator fundamental para definição do tratamento preservativo da madeira. Para isto foi projetado e construído um equipamento alternativo, para uso laboratorial, visando determinar a permeabilidade e analisar qual espécie dentre as estudadas seriam mais permeáveis a fluidos líquidos e gasosos em madeiras brasileiras de florestas plantadas. O equipamento construído permite a determinação do escoamento de fluidos em corpos-de-prova cilíndricos de madeira, em todas as suas direções ortogonais. Os resultados obtidos mostram que o equipamento é adequado para a determinação da permeabilidade a líquido ou gás em madeiras, onde na direção longitudinal, o alburno E. grandis é a parte do lenho mais permeável a líquido e gás, seguido do alburno do E. citriodora, Pinus elliottii e cerne do E. grandis. Com exceção do Pinus elliottii na direção transversal, as demais espécies não apresentaram vazão nesta direção. / This work aims to study permeability of wood especially in reforestation species like Pinus elliotti, Eucalyptus grandis and Eucalyptus citriodora in order to evaluate how much a given wood species is permeable to preservatives (chemical treatments) and how much it is permeable to application of structural adhesives (making of structural pieces in Glued Laminated - MLC). Evaluation of permeability is a fundamental factor when defining the preservative treatment to able applied in the wood, so an alternative equipment has been especially designed and built aiming to determine its permeability and analyze which one of the studied Brazilian reforestation species would be more permeable to liquid and gaseous fluids. This laboratorial equipment has allowed determination of fluid drainage in cylindrical samples of wood in all of its orthogonal directions. Obtained results have shows that it is appropriate for determining liquid or air permeability of wood where, in longitudinal direction, E. grandis sapwood has been the most permeable part, followed by E. citriodora sapwood, Pinus elliottii and E. grandis heartwood. None of the species has presented any flow in traverse direction, except Pinus elliottii.

Cryopreservation of adherent cells may be advantageous for cell types that are difficult to preserve in suspension or when it is necessary to preserve characteristics of the adherent cultured cells. Vitrification is a promising procedure for the preservation of adherent cells that prevents ice crystal formation and the resulting dissociation and morphological damage. To successfully vitrify adherent cells, high concentrations of CPA are required which increases the likelihood of osmotic and toxic damage. In this dissertation, we describe a rational design strategy that predicts mathematically optimized CPA addition and removal procedures based on the minimization of a toxicity cost function. These rationally designed procedures rely on the accurate knowledge of cell biophysical parameters. We validate an in situ calcein fluorescence quenching method for the determination of membrane permeability parameters for adherent cells. We also describe the determination of osmotic tolerance limits for adherent cells. We use rational design strategies to determine CPA addition and removal procedures for adherent endothelial cells, neuronal cells, and induced pluripotent stem cells as well as oocytes. Also, we provide experimental support for the feasibility of these methods using adherent endothelial cells. The mathematical methods and experimental procedures outlined in this dissertation are important tools for the design of addition and removal procedures for concentrated CPA solutions. This dissertation is an important step toward successful design and implementation of vitrification strategies for adherent cells and tissues. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Feb. 14, 2013 - Feb. 14, 2015