Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 16, 2010). Includes bibliographical references. Also issued in print.

Previous studies have suggested that advection from the Mexican Plateau (MP) may influence rainfall over Texas in spring and summer; generally air ascends over the cordillera and descends over the southern plains. The two mechanisms may link the northern Mexico drought to Texas drought. Observations and the Community Earth System Model are used in this study to describe the 2011 Texas-northern-Mexico drought and examine the role of the MP on the hydro-climate over the southern US, providing implications for the linkage between the MP and rainfall over Texas. A control run and three experimental runs were performed with prescribed sea surface temperatures and sea ice fractions. The results show that when the MP becomes dry, rainfall declines locally and downstream. During the spring, the dry air brought to Texas by prevailing westerly winds suppresses local convection; but dry air advection from the highlands has little influence on rainfall over Texas during the summer when Texas is no longer in the downstream areas. During the summer, a warmer MP draws moist air over the peripheral low elevation areas to the highlands; it bends the low-level jet towards the highlands and an anti-cyclonic flow anomaly forms over the southern US, which causes air to diverge and tends to reduce rainfall over the southern US. / text

The onset of fire within a compartment can pose a hazard to the occupants and the structure containing the compartment. Fire suppression systems aim to either extinguish or suppress an incipient fire before loss of life or damage to the structure can occur. The geometry and use of the compartment as well as the fuel packages within must be taken into account when choosing an appropriate fire suppression system. This thesis explores novel suppression methods inside of compartments. Los Alamos National Laboratories came to the University of Texas Fire Research Group (UTFRG) to characterize and investigate the fire danger inside of nuclear gloveboxes. The first suppression method discussed explores activation tests of a commercial automatic fire suppression system (Fire Foe [superscript TM]) containing heptaflouropropane (FE-36) fire suppressant conducted within a glovebox at the UTFRG's burn structure. Temperature and time to activation data of ten tests at four different fire sizes, three 13 kW, one 20 kW, three 25 kW, and three 50 kW, was taken. Gas temperatures from experiments were compared against NIST's Fire Dynamics Simulator (FDS) gas temperatures with good agreement. The time and spatially averaged net heat flux on a virtual Fire Foe [superscript TM] tube from the FDS simulations were passed to a thermo-physical, semi-empirical, sub-model to predict activation with poor agreement from experimental activation times. A Bayesian parameter inference was later run on the sub-model. While the Bayesian inference approach is able to match sub-model temperatures to experimental temperatures, some non-physical values for heat transfer coefficients and view factors were observed at the lower heat release rate fires. Micro combustion calorimetry (MCC) was used to determine heat of combustion of glovebox glove material and cone calorimetry tests were run to find ignition time versus incident heat flux. Using standard ignition time models, effective model parameters were calibrated. Thermal characterization of the glove material showed that the heat of combustion found from MCC was within the range of heats of combustion for other non-halogenated materials found in the literature. Analysis of the time to ignition tests showed that the glove material should be modeled as thermally thick when one would expect thin behavior. This behavior was attributed to possible heat losses from the back of the glove material. Dry water is expected to have similar suppression characteristics as water mist systems because the dry water particle sizes are on the order of water mist droplet sizes. The major benefit with dry water is the low pressures needed to drive the aerosol. An issue encountered with the dry water was flowing it in the way one would flow normal water. It was found that at low normal and shear stresses, the dry water clathrates would release the water held inside. A possible low shear delivery mechanism was discussed that avoids the ratholing effect. A continuous dry water production system was also designed. Filter loading tests were conducted to determine the quality of the dry water collected from the batch and continuous cases. It was observed that the ratio of water to silica for the continuous case reaches the batch value and is similar to results found in the literature. For the batch dry water it was observed that the particle size of the dried clathrates does vary with rotational speed of the blender and is independent of the type of water used (tap or deionized). / text

The influence of the size and morphology of carrier particles on drug dispersion performance from passive dry powder inhalers has been extensively studied topic, and a consensus has been reached regarding the adverse effect that larger carrier particle diameters impart to aerosol performance. However, previous studies have generally employed only a few carrier particle size fractions, generally possessing similar surface characteristics. Accordingly, theories developed to explain the influence of the physical characteristics of carrier particles on performance relied heavily on both extrapolation and interpolation. To fill in the gaps from the literature and simultaneously evaluate the influence of carrier particle size and morphology, a comprehensive study was undertaken using 4 lactose grades, each sieved into 13 contiguous sizes, to prepare 52 formulations incorporating a unique lactose grade-size population. The aerosol performance results indicated that large carrier particles possessing extensive surface roughness can improve drug dispersion, in contrast to what has been previously reported. It is proposed that this may be attributed to mechanical detachment forces arising from collisions between the carrier particle and inhaler during actuation. Based on these observations, a novel dry powder inhaler platform was developed, employing carrier particles much larger (> 1 mm) than previously explored in both the scientific and patent literature. Optimization of this technology required the judicious selection of a carrier material, and following an extensive screening process, low-density polystyrene was selected as a model candidate. Given its low mass, diameters in excess of 5-mm could be employed as carriers while still generating high detachment forces. To minimize drug particle aggregation, a novel drug-coating method employing piezo-assisted particle dispersion was developed to compensate for the reduced surface area of the novel carrier particles. In addition, the selection of a suitable inhalation device prototype was instrumental to the overall performance of the technology. In vitro testing of the novel large carrier particles yielded emitted fractions in excess of 85%, and overall drug delivery of up to 69% of the nominal dose. / text

Torra ögon beror på en tårfilmsdefekt och ger symtom såsom skav, irritation och dimsyn. Symtomen kan orsakas av till exempel sjukdomar, läkemedelbiverkningar eller miljöfaktorer. Syftet med denna pilotstudie var att undersöka patienters upplevelser av att ha torra ögon. Studien genomfördes som en kvalitativ intervjustudie med en induktiv ansats. Databearbetningen genomfördes med hjälp av en manifest innehållsanalys. Följande kategorier framkom: fysisk påverkan, begränsningar, att bli tagen på allvar, utvecklat ett förhållningssätt till sin situation samt stöd och social gemenskap. Patienter med torra ögon upplever att de påverkas fysiskt genom att ögonen till exempel skaver, kliar och smärtar. Vissa miljöer och aktiviteter påverkar symtomen i negativ riktning. Patienterna påverkas i sin vardag på så sätt att de har svårigheter att se på tv, att köra bil under längre tid eller att läsa. Vissa miljöer kan vara ansträngande att arbeta i. Bemötande och information från ögonsjukvården upplevs ibland som bristfällig. Patienterna verkar ändå acceptera sin situation, prövar sig fram och försöker hitta lösningar. Att kunna träffa och diskutera sin situation och sina behandlingar kring torra ögon med andra patienter i samma situation upplevs som positivt, då detta bidrar till social gemenskap och utveckling av egenvården. Ökad förståelse för hur patienter med torra ögon påverkas och upplever sin situation är viktigt för att kunna tillgodose patienternas egenvårdsbehov och för att ge sjukvårdspersonal evidensbaserad kunskap. Mer forskning, såväl flera som mer omfattande studier behövs för att öka kunskapen om patienter med torra ögon. / Dry eyes are due to a tear film defect, give symptoms such as chafing, eye irritation and blurred vision. The symptoms may be caused by, diseases, medication side effects or environmental factors. The aim of this pilot study was to examine patients ' experiences of having dry eyes. The study was conducted as a qualitative interview study with an inductive approach. Data processing was performed using a manifest content analysis. The following categories emerged; physical impact, limitations, to be taken seriously, developed an approach to his/her situation, and support and social community. Patients with dry eyes feel they are physically affected by chafing, itching and pain. Some environments and activities affect the symptoms in a negative direction. The patients are affected in daily life, such as difficulties watching television, to drive a car for longer periods of time, or to read. The personal treatment and information from staff in an eye department are sometimes seen as failing. Patients seem to accept their situation, they are testing their own ways trying to find solutions. To be able to meet and discuss their situation and their treatments of dry eye with other patients in the same situation is perceived as positive, as this contributes to a sense of social relationship and a development of patient self-care. Better understanding of how patients with dry eye are affected by and experiences their situation is important in order to meet patients ' self-care needs and to provide the medical staff evidence-based knowledge. There is a need to increase the knowledge about patients with dry eyes and their experiences to this problem. More extensive studies in this area need to be accomplished.

Over 110,000 known methamphetamine (meth) clandestine labs were reported in the U.S. from 1999 to 2008. The production of meth is regarded as a national epidemic, and can lead to substantial contamination of indoor materials. Due to its chemical and physical properties, meth residual can persist on indoor surfaces and in indoor air for prolonged periods. Unfortunately, most remediation techniques lack strong scientific support and cleanup standards are inconsistent across different states. A better understanding of the mechanistic interactions between meth and indoor environment can help improve remediation strategies and the development of regulations. In this study, equilibrium partitioning coefficients (Ke) between a meth surrogate and wall materials were estimated based on laboratory experiments. The resulting Ke values were then used in a screening model to predict meth decay rates from wall materials and indoor air. The effects of ventilation and indoor air mixing on meth off gassing were explored. / text

Recent experimental and simulation studies -conducted at the Department of Petroleum Engineering at Texas A&M University - confirm oil production is accelerated when propane is used as an additive during steam injection. To better understand this phenomenon, distillation experiments were performed using seven-component synthetic oil consisting of equal weights of the following alkanes: n-C5, n-C6, n-C7, n-C8, n-C9, nC10, and n-C15. For comparison purposes, three distillation processes were investigated: dry-, steam-, and steam-propane-distillation, the latter at a propane:steam mass ratio of 0.05. The injection rate of nitrogen during dry-and steam-distillation was the same as that of propane during steam-propane distillation, 0.025 g/min, with steam injection rate kept at 0.5 g/min. The distillation temperatures ranged from 115°C to 300°C and were increased in steps of 10°C. The cell was kept at each temperature plateau (cut) for 30 minutes. Distillation pressures ranged from 0 psig for dry distillation to 998 psig for steam-and steam-propane distillation. The temperature-pressure combination used represented 15°C superheated steam conditions. Distillate samples were collected at each cut, and the volume and weight of water and hydrocarbon measured. In addition, the composition of the hydrocarbon distillate was measured using a gas chromatograph. Main results of the study may be summarized as follows. First, the hydrocarbon yield at 125°C is highest with steam-propane distillation (74 wt%) compared to steam distillation (58 wt%), and lowest with dry distillation (36 wt%). This explains in part the oil production acceleration observed in steam-propane displacement experiments. Second, the final hydrocarbon yield at 300°C however is the same for the three distillation processes. This observation is in line with the fact that oil recoveries were very similar in steam- and steam-propane displacement experiments. Third, based on the yields of individual hydrocarbon components, steam-propane distillation lowers the apparent boiling points of the hydrocarbons significantly. This phenomenon may be the most fundamental effect of propane on hydrocarbon distillation, which results in a higher yield during steam-propane distillation and oil production acceleration during steam-propane displacement. Fourth, experimental K-values are higher in distillations with steam-propane for the components n-hexane, n-heptane, n-octane, and n-nonane. Fifth, vapor fugacity coefficients for each component are higher in distillations with steam-propane than with steam. Finally, Gibbs excess energy is overall lower in distillations with steam-propane than with steam. The experimental results clearly indicate the importance of distillation on oil recovery during steam-or steam-propane injection. The experimental procedure and method of analysis developed in this study (for synthetic oil) will be beneficial to future researchers in understanding the effect of propane as steam additive on actual crude oils.

In this paper is present information about dry power transformers mechanical design, common electrical characteristics, and electrical characteristics. There compare oil transformers and dry power transformers. There are given conclusions about possible in practice use dry transformers and some to offer a suggestion how to pick and choose transformers.

Dry eye is a complex, multi-factorial disease that results in a compromised tear film and ocular surface. Clinicians and researchers alike have historically relied on an individual’s symptoms to diagnose and manage the condition, due to a lack of reliable objective methods for quantifying disease presence and severity. Of late, parameters such as tear film osmolarity and tear meniscus height have shown promise as valid methods for enumerating characteristics of the tear film that may aid the diagnosis of dry eye. Two new technologies have recently been introduced that can measure said parameters. The TearLab™ is a novel handheld nano-osmometer capable of measuring tear film osmolarity on samples as small as 50 nL. The device uses electrical conductance to measure osmolarity, and the small sample requirements purportedly allows the device to minimally disturb the natural state of the tear film. The RTVue-100 is a spectral-, or Fourier-domain optical coherence tomographer that has the ability to generate high resolution, cross-sectional images of the tear meniscus, and subsequently measure tear meniscus height. As little is published on the use of these technologies to evaluate the tear film, a series of studies was completed to determine their performance in both a normal and dry eye population.

No description available.