Substance use disorders (SUDs) such as opioid addiction account for a large portion of the total global burden of disease. Nearly 5% of all disability-adjusted life years and 4% of overall mortality appear to be attributed to SUDs. An SUD, such as opioid use is often characterized by its addictiveness and frequent relapse among those who attempt quitting. Despite traditional methods of treatment, 5-year relapse rates are as high as 97% for opioid dependence. Alternative or novel forms of treating opioid addiction should be investigated and adopted, especially in countries which face an “epidemic” of opioid use and dependence, such as the United States. Ibogaine is a naturally occurring indole alkaloid that may be an effective alternative form of treatment for individuals struggling with opiate addiction and/or withdrawal. Preliminary research has found that iboga alkaloids such as ibogaine are effective at reducing morphine self-administration in rats. An elaborate history of human case reports has found ibogaine to be successful at reducing drug self-administration, withdrawal symptoms, and ceasing opioid cravings. The complex pharmacological profile of ibogaine is mediated by several classes of neurological receptors and transporters, including the sigma-2, kappa- and mu-opioid, 5HT2 and 5HT3 receptors, 34 nicotinic receptors, and the N-methyl-d-aspartic acid ion channel. Ibogaine’s combined interaction with all of these receptors has been suggested to reset or normalize neuroadaptation related to drug sensitization and tolerance. The resulting anti-addictive physiological and psychological properties appear to persist beyond pharmacokinetic elimination from serum or brain tissue, but may also cause unwanted side effects such as cardiovascular and neurologic toxicity. Developing a safe and effective standard dosing regimen has proven to be difficult in humans. The controversial therapeutic use of ibogaine in medical and nonmedical settings has been called a “vast uncontrolled experiment” or “medical subculture”, and ibogaine remains unscheduled in much of the world. However, ibogaine does not appear to have potential for recreational or other forms of abuse. During the 1995 Ibogaine Review Meeting, none of the consultants to NIDA were concerned about the abuse of ibogaine. Opiate users struggling with addiction and also interested in ibogaine therapy prompted the formation of “informal” treatment networks. Ibogaine therapy clinics catering to foreigners have also become more common in the Caribbean and Latin America. In order to clarify ibogaine’s clinical safety and therapeutic use against opiate dependence, the following thesis will investigate and analyze the ibogaine literature. Areas of focus for future ibogaine research will be identified, such as the invention of ibogaine congeners that retain efficacy against opioid dependence, but minimize unwanted toxic or psychological effects.

<p> The effects of cultural intensity (operational and intensive) and planting densities (741, 1483, 2224, and 2965 ha^-1) on modulus of elasticity (MOE), modulus of rupture (MOR) and specific gravity (SG) of small clear samples obtained from 15 and 16 year-old loblolly pine (<i> Pinus taeda</i>) from the Lower Coastal Plain and Piedmont region of the southeastern United State were examined. Planting density and distance from pith showed a significant (<i>p</i> &lt; 0.0001) and strong main effect on stiffness (MOE) and strength (MOR) for the samples. Regardless of planting density, MOE, MOR and SG of samples increased significantly from pith toward bark. A significant culture &times; density interaction (<i> p</i> &lt; 0.0001) was observed for the samples obtained from the Lower Coastal Plain. </p><p> The project also determined the feasibility of measuring microfibril angle (MFA) on solid wood loblolly pine samples using scanning electron microscopy and transmission electron microscopy with the angle analyzed using image analysis. Measurements of MFA revealed minor differences (5⁰) between juvenile wood and mature wood.</p>

<p> The southern pine species group is the main softwood resource used in the U.S, and the majority of southern pine is used in lumber production. The use of lumber in structural purpose requires feasible strength and stiffness grading method ensuring characteristics allowable stress values. The stiffness and strength of most of southern pine lumber is assessed using visual grading system. The objective of this study was to evaluate a production weighted sample of 2 &times; 4, 2 &times; 6, 2 &times; 8, and 2 &times; 10 No. 2 grade southern pine lumber collected across its geographic range. The results of this research show a snapshot of the material commercially sold in the southern U.S. region. Over one third of the specimens contained pith, and had an average mean value of 4.6 for number of rings per inch (RPI) and 43.8% for latewood (LW). The overall specific gravity (SG), modulus of elasticity (MOE) and modulus of rupture (MOR) were 0.54, 10.1 GPa, and 41.7 MPa, respectively. The allowable design bending strength (F_b) for 2 &times; 4, 2 &times; 6, 2 &times; 8, and 2 &times; 10 was 11.2, 9.2, 8.1, and 7.1 MPa, respectively. Specimens containing no pith, RPI higher or equal then 4.0, and LW higher or equal then 33.0% were greater in MOE and MOR. The effect of grading controlling characteristics of the material was also studied. The presence of knots had the most significant impact on mechanical properties. Specimens with wane and shake had greater SG, MOE, MOR, F_b values than specimens with others grading controlling characteristics. The mean values found for RPI, LW, and SG met the requirements recommended for southern pine No. 2 lumber. The MOE and F_b values found therein met the previous and the new allowable design value. The results of this research can be used to identify and to select the best variables to improve the prediction of bending properties of visually graded lumber.</p><p>

<p> Although incipient fungal decay of wood may be difficult to detect early, it causes a significant decrease in wood strength. Developing a reliable method of decay identification to overcome wood replacement costs by non-destructive methods is necessary. This study investigates a possibility of identifying fungal volatile organic compounds (VOCs) as means of fungal detection using solid phase micro-extraction (SPME) coupled with gas chromatography&ndash;mass spectrometry (GC-MS). </p><p> Volatile emissions from two brown rot (<i>Gloeophyllum trabeum</i> and <i>Postia placenta</i>) and two white rot (<i>Trametes versicolor</i> and <i>Irpex lacteus</i>) fungi on pine and aspen and their profiles related to wood mechanical strength and mass loss were investigated over 12 weeks. Principal component analysis of VOCs spectra differentiated volatiles from decayed and sound wood. Volatiles from two fungal species revealed distinct patterns of early and late degradation stages. SPME combined with GC-MS showed promissing results for non-destructive identification of incipient decay in wood structures.</p><p>

<p> The objective of this dissertation was to develop a process for the production of acetic acid in kraft mills. Acetyl groups in hardwood can be hydrolyzed using alkali at 50 &deg;C. The product from this process contains about 15 g/L of sodium acetate and was determined to be suitable for the production of acetic acid.</p><p> Experiments performed using aqueous sodium acetate to evaluate the ability of electrodialysis (ED) to separate and concentrate sodium acetate showed that sodium acetate can be concentrated up to 275 g/L starting with an initial concentration of 17 g/L. The transport of water with sodium and acetate ions through ED membranes limited the maximum obtainable concentration.</p><p> To avoid the deleterious effects of white liquor on ED, selectivity experiments were performed using synthetic oxidized white liquor extract. These experiments showed a decrease in the efficiency of ED process due to the presence of sodium carbonate and sodium sulphate in the extract. Hence, it was concluded that caustic should be used as the extraction solvent.</p><p> Bi-polar electrodialysis (BPMED) experiments performed using sodium acetate showed that up to 200-280 g/L of acetic acid can be produced using BPMED. Although higher concentrations of sodium hydroxide can also be produced using BPMED, 30 g/L concentration was considered to be sufficient for recycle to the extraction process.</p><p> Feed and bleed mode BPMED experiments were performed to determine the current efficiencies and the suitable inlet concentration of sodium acetate for the production of up to 200 g/L of acetic acid. Both feed and bleed mode and batch experiments showed that the current density was the major driving force for BPMED.</p><p> Two types of concentrated wood extracts; namely (1) clarified and (2) unclarified were prepared with and without the lignin removal pre-treatment, respectively. The results of the ED and BPMED experiments performed using these extracts were similar to those of the synthetic sodium acetate. A major difference involved an increase of about 15% in electric energy consumption arising from the transport of formate, lactate and glycolate salts. The color of the anionic membranes slightly changed after processing unclarified extract through ED and BPMED.</p>

<p> The lignocellulosic biorefinery concept provides an attractive alternative to energy, fuels and chemical production from petroleum-derived and other non-renewable resources. However, the realization of this technology is limited by the economic climate and the technical challenges of maximizing the biorefinery production yield.</p><p> This dissertation is an investigation of utilizing targeted Engineered Biomass Deconstruction (EBD), or mechanical refining, to overcome the inherent recalcitrance of the lignocellulosic biomass. This recalcitrant nature is often considered the limiting factor for the commercialization of cellulosic biorefineries &ndash; including second generation cellulosic ethanol production facilities &ndash; which increases the direct costs for the process inputs of the deconstruction steps. This includes requirements of high temperature and chemical charges during pretreatment and high enzyme dosages during enzymatic hydrolysis unit operations.</p><p> First, the effects of mechanical refining on the digestibility lignocellulosic biomass is explored at the laboratory scale. Comparisons of two common laboratory scale refiners, PFI mill and valley beater, confirm improvements in enzymatic hydrolysis with increased mechanical refining severity for all biomass pretreatments; including, kraft (NaOH, Na₂S), green liquor (Na2CO3, Na₂S), and sodium carbonate (Na₂CO₃) pretreatments. A maximum in refining improvement is observed, highlighting the ability of EBD to generate the most value for the lignocellulosic biorefinery at moderate pretreatment severities and hydrolysis conditions.</p><p> Second, Engineered Biomass Deconstruction is compared at lab, pilot and industrial scales. Using the same industrially sourced sodium carbonate pretreated biomass, similar enzymatic hydrolysis kinetics and their respective improvements with mechanical refining were observed for all mechanical refining scales, with the most similar kinetics being between commercial scale and pilot scale refining. Successful simulation of industrial scale refining allows the use of pilot scale refining for optimization of Engineered Biomass Deconstruction at the pilot scale.</p><p> Third, utilizing the same commercial sodium carbonate biomass, the pilot scale mechanical refining conditions were optimized. Close to theoretical maximums in enzymatic hydrolysis conversion were achieved using pilot scale EBD compared to the total carbohydrate conversion of 39% for unrefined hardwood sodium carbonate biomass. Mechanical refining conditions of temperature, plate gap width, and consistency were controlled to optimize the Engineered Biomass Deconstruction process. Optimum conditions for the pilot refiner were found to be to 0.13 mm plate gap width, and 20% biomass consistency, at ambient temperature, which produced a total carbohydrate conversion of 90%.</p><p> Following the optimization of EBD conditions, efforts were made to fundamentally understand the reason for the improvement in biomass digestibility with mechanical refining. The motivation of this understanding would facilitate the development and application of engineered biomass deconstruction technologies within the lignocellulosic biorefinery concept. Non-hydrolytic fluorescent recombinant protein probes with carbohydrate binding modules of similar size to commercially available cellulases were used a model for the enzyme adsorption process for the initial stages of enzymatic hydrolysis. Model substrates were used to confirm the selective binding of the fluorescent protein probes to cellulose. Confocal laser scanning microscopy allowed for visualization and quantitative imaging of the fluorescent markers within the lignocellulosic biomass matrix. Relationships between the maximum fluorescent intensities and the different lignocellulosic biomass were observed. The distribution of adsorbed enzymes in the cell wall were altered by the mechanical refining actions of external fibrillation, internal delamination, and cutting. This indicates that improved biomass accessibility to enzymes throughout the lignocellulosic biomass matrix is related to enhanced enzymatic hydrolysis.</p><p> This work highlights the effectiveness of Engineered Biomass Deconstruction and its benefits when applied within the lignocellulosic biorefinery concept. Future research should be targeted for further optimization of mechanical refiner operating conditions including specific development of new refiner plate designs for application in a lignocellulosic biorefinery.</p><p>

<p> The objective of this study was to investigate the effects of weathering on the performance of intumescent fire-retardant coatings on wooden products. The weathering effects included primary (solar irradiation, moisture, and temperature) and secondary (environmental contaminants) parameters at various time intervals.</p><p> Wildland urban interface (WUI) fires have been an increasing threat to lives and properties. Existing solutions to mitigate the damages caused by WUI fires include protecting the structures from ignition and minimizing the fire spread from one structure to another. These solutions can be divided into two general categories: active fire protection systems and passive fire protection systems. Passive systems are either using pre-applied wetting agents (water, gel, or foam) or adding an extra layer (composite wraps or coatings). Fire-retardant coating treatment methods can be divided into impregnated (penetrant) and intumescent categories. Intumescent coatings are easy to apply, economical, and have a better appearance in comparison to other passive fire protection methods, and are the main focus of this study.</p><p> There have been limited studies conducted on the application of intumescent coatings on wooden structures and their performance after long-term weathering exposure. The main concerns of weathering effects are: 1) the reduction of ignition resistance of the coating layer after weathering; and 2) the fire properties of coatings after weathering since coatings might contribute as a combustible fuel and assist the fire growth after ignition.</p><p> Three intumescent coatings were selected and exposed to natural weathering conditions in three different time intervals. Two types of tests were performed on the specimens: a combustibility test consisted of a bench-scale performance evaluation using a Cone Calorimeter, and a thermal decomposition test using Simultaneous Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) method (also known as SDT). For each coating type and weathering period, three different radiative heat flux levels were used in the combustibility tests. Data obtained from the tests, including flammability and thermal properties, were gathered, analyzed, and compared to non-weathered specimens.</p><p> The results revealed visible effects of weathering on pre (and up to)-ignition flammability and intumescent properties, especially decreases in Time-to-Ignition (TTI), Time-to-Intumescence (t_intu.), and (maximum) Intumescence Height (H_intu.) values in weathered specimens. These results showed that the ignition resistance of the coating layers decreased after weathering exposure. On the other hand, the obtained results from weathered specimens for the post-ignition flammability properties, especially Peak Heat Release Rate (PHRR) and Effective Heat of Combustion (EHC) did not show a significant difference in comparison to the non-weathered samples. These results demonstrated that the weathered coating layer would not likely to act as an additional combustible fuel to increase fire spread.</p>

<p> The waste fines (WF) rejected by paper mill are one of the good resources of lignocellulosic biomass to produce sugars. The potential of hydrolysis yield was around 95% (reducing sugars g/g of digestible fibers). The inhibitory effects of the substrate were studied since the enzyme demand for the hydrolysis was not economically feasible.</p><p> The major inhibitor of WF was the high portion of ash for enzymatic hydrolysis. The CaCO₃ among the ash was the strongest inhibitor with three different inhibiting effects. The first inhibition was related to reduced free enzyme in bulk solution resulted by non-productive enzyme adsorption on CaCO₃. The binding mechanism could be explained by the electrostatic and hydrogen bonding interaction between the enzyme and CaCO₃. The major mechanism of the enzyme &ndash; CaCO₃ binding differ with the enzyme &ndash; lignin binding which has been reported that the hydrophobic interaction is the major mechanism for the enzyme &ndash; lignin binding. The different mechanisms are due to the hydrophobic property: CaCO₃ is hydrophilic and lignin is hydrophobic. The application of a nonionic surfactant, Tween 80, could be a solution to free enzyme in bulk solution via competitive bond on CaCO₃ with a higher affinity than the enzyme. A study of CaCO₃ of particle size and Tween 80 adsorption on CaCO₃ provided evidence of this Tween 80 effect. The second inhibiting effect of CaCO₃ was pH level shift decreasing enzyme activity by dissolved Ca²⁺. pH adjustment (PAD) was tested with addition of acids to make the pH optimum for enzyme activity. PAD with extra acetic acid resulted in a positive effect but sulfuric acid did not improved hydrolysis yields. The combination application of Tween 80 and PAD yielded more than two times as much sugar release compared to the non-treated waste fines with a 10 FPU enzyme dose. The final inhibitory effect of CaCO₃ was dissolved Ca²⁺ reduced of enzyme activity. This effect was supported by the reduction of hydrolysis yield of Avicel and unbleached kraft pulp (UKP), and documentation of particle size increase due to the aggregation of enzyme in the presence of Ca²⁺.</p><p> Some other approaches were studied to improve the hydrolysis yield of paper mill waste fines. These included using combinations of adding nonionic surfactant, high consistency hydrolysis, buffer substitution, and deinking flotation. Each method improved the productivity or reduced the cost of production and may be combined in one process to get synergetic effects.</p>

No description available.

Master of Science / Apparel, Textiles, and Interior Design / Sherry J. Haar / This study compared the colorfastness of potassium aluminum sulfate (PAS) mordanted and nonmordanted 30/2 wool yarn, dyed with black walnut (Juglans Nigra), Osage orange (Maclura pomifera), and eastern redcedar (Juniperus virginiana) sawdust. Information from this study is intended to inform natural dye artisans and to increase the profitability of sawdust for farmers, ranchers, and mill owners who would otherwise find little use for this byproduct of timber manufacturing. Pre-testing ensured dyeings of visually comparable color depth and dye concentrations were pre-tested to find a standard depth of shade between the same dye on PAS mordanted and nonmordanted wool yarns. Tests for colorfastness to light, laundering and staining were performed in accordance to AATCC test methods. Resulting colors for exposed and unexposed specimens were rated using CIE L* a* b* values and AATCC gray scale for color change. GLM Anovas and two-sample t-tests were used to statistically analyze CIE L* a* b* values. As expected, findings indicated that dye absorption was improved with the use of a PAS mordant, especially for black walnut and eastern redcedar. For yarns premordanted with PAS the dyewoods became yellower. A PAS mordant slightly improved colorfastness to light for black walnut and eastern redcedar, but did not influence Osage orange which had an unexpected color change from bright yellow to warm brown after exposure to light. Colorfastness to laundering was slightly improved with PAS for Osage orange, while black walnut and eastern red cedar had slightly less color change without the mordant. This research was supported by the Agricultural Research Experiment Station and Kansas State University.