Multiple Regression Inference of Yield for Douglas-fir Plantations in the Pacific Northwest

Thesis (Master's)--University of Washington, 2012Multiple regressions were formulated with predictor variables of latitude, longitude, and elevation, stand stocking, age, and site index for western Oregon, western Washington, and southwest British Columbia. Models were assessed for normality using plots of studentized residuals by fitted values, q-q plots, and fit was assessed by R2 value. Outliers were examined based upon Bonferroni p-values and Cook's distance. The developed seven multiple regression models were for response variables of cubic foot volume including top, cubic foot volume to top 4 and 6 inches in diameter, and Scribner board foot volume to top 4 and 6 inches in diameter. These models were used to examine the effects of early density controls and the effects of subsequent heavy first thinnings on volume yield. The assessment concluded that early density controls resulted in highest to lowest productivity in the order of 100 initial Trees Per Acre (TPA), 300 TPA, 500 TPA, and 700 TPA. In assessing effects from a first thin, the 300 TPA class was shown to have the most increased volume. The first thinning in the 500 and 700 TPA levels showed an overall minimal increase in volume and diameter size due to a longer delay in allocating growth from the crown to the stem. The models produced in this study can be of use in assessing and understanding predictions made by other regional growth models

The perceptions of end-of-life decision making and hospice care of IU Mien elders

The use of hospice services has increased over past 10 years, but minority access has been limited (Harber, 1999). In order to better understand the reasons for limited access to hospice by the Iu Mien community, this study explored the perceptions of death, end-of-life (EOL) decision-making, and attitudes about hospice philosophy of Iu Mien elders (N = 8). The Iu Mien community in the United States is small (approximately 35-50,000) (Barker & Saechao, 1997; Macdonald, 1997; Schuldberg, 2005) with unique spiritual and religious beliefs. Since the literature is limited on this population, it is vital to learn about how to better serve their community. The results of the study indicated that not only is the Iu Mien community influential in an individual's perception of death and dying, but that there is a need for culturally sensitive educational outreach regarding EOL care, including hospice services, to the Iu Mien community.CSU, Chic

An investigation on peeling recovery and quality of senile plantation-grown rubber trees in Laos

The study assessed the peeling potential of rubber trees past the prime latex-producing age when the latex yields become non-economical. Fifteen 25-year-old plantation-grown trees were harvested and peeled using spindleless lathe technology. Following peeling, veneer sheets were measured and graded to determine volume and quality recoveries. Relationships between billet characteristics and recoveries or quality were examined and a recovery predictive model proposed. Most of the main causes identified for downgrading face veneers were either processing-related issues or drying-induced defects. Thus, a combination of several optimisation techniques could annihilate most of the main causes of downgrading veneer, potentially leading to a substantial proportion of higher-quality veneers typically used where surface decorative appearance is a primary consideration. The results demonstrated that rubber trees past their latex-producing prime from unthinned and unpruned stands have qualities and desirable traits to potentially produce certain high-value engineered wood products. Senile rubber trees in Laos could represent significant additional revenue to growers and a source of raw material to the industry which, theoretically, could be converted into high-value products if other factors can be overcome

Levofloxacin-Proliposomes: Opportunities for Use in Lung Tuberculosis

Levofloxacin (LEV) is a relatively new-generation fluoroquinolone antibiotic that has good activity against <em>Mycobacterium tuberculosis</em>. The aims of this study were to develop and evaluate LEV-proliposomes in a dry powder aerosol form for pulmonary delivery. LEV-proliposomes containing LEV, soybean phosphatidylcholine, cholesterol and porous mannitol were prepared by a spray drying technique. The physicochemical properties of LEV-proliposomes were determined using a cascade impactor, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier transform <em><em>infrared</em></em><em> </em>spectroscopy (FT-IR). The toxicity of proliposomes to respiratory-associated cell lines and its potential to provoke immunological responses from alveolar macrophages (AMs) were evaluated. Antimycobacterial activity using flow cytometry and an <em>in vivo</em> repeated dose toxicity test in rats were carried out. LEV-proliposomes were successfully prepared with mass median aerodynamic diameters of 4.15–4.44 μm and with fine particle fractions (aerosolized particles of less than 4.4 µm) of 13%–38% at 60 L/min. LEV-proliposomes were less toxic to respiratory-associated cells than LEV, and did not activate AMs to produce inflammatory mediators that included interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and nitric oxide. The minimum inhibitory concentration (MIC) against <em>M. bovis</em> of LEV and LEV-proliposomes containing LEV 10% were 1 and 0.5 µg/mL, respectively. The efficacy of LEV-proliposomes against <em>M. bovis</em> was significantly higher than that of free LEV (<em>p</em> < 0.05). The efficacy of the LEV-proliposomes against <em>M. tuberculosis</em> was equal to that of the free LEV (MIC = 0.195 µg/mL). In a repeated dose toxicity study in rats, renal and liver toxicity was not observed. LEV-proliposomes should now be tested as an alternative formulation for delivering LEV to the lower airways