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Fractionation and Characterization of a Pine Pyrolysis Bio-Oil and In Vivo and In Silico Analysis of Its Anti-IL-17 Effects on HaCaT Human Keratinocytes
Full text linkPsoriasis is an incurable skin disease affecting about 2-3% of the world's population. Interleukin 17 (IL-17) is a proinflammatory cytokine recognized to play a crucial role in psoriasis etiology and evolution. Monoclonal antibodies targeting IL-17A (secukinumab, ixekizumab) or its receptor (brodalumab) are available for treating psoriasis. However, their high costs, impossibility of use by topical route, and associated adverse events generate a need for identifying new anti-IL17 natural molecules. The goal of this study was to expand on earlier studies showing the beneficial effects of raw pyrolysis bio-oil on regulating IL-8 levels in keratinocytes via inhibiting IL-17. The investigation started by examining the side effects and pharmacological interactions of traditional herbal therapies for psoriasis. The bio-oil fractionation procedure was then revised and improved in the research to produce five different bio-oil fractions, each of which was characterized and put to the test on keratinocytes stimulated with IL-17. The most consistent anti-IL-17 action was seen in the aqueous fraction, which contained three pure compounds. The levels of IL-8 were effectively modulated by the mixture of two of these compounds, namely, acetic acid and acetol. According to RNA-Seq data, mitogen-activated protein kinase (MAPK) activity was found to be negatively regulated by 29 genes. This study was successful in locating effective anti-IL-17 molecules and offering details on their potential mechanisms of action
Understanding the Molecular Interactions Between the Major Food Polymers, Including Starch, Protein, and Fiber, as Impacted by Extrusion Processing
Full text linkHealth and environmental awareness as well as changes in lifestyle go hand in hand with significant changes in human diet. Snackification, the displacement of larger meals by snacks, and vegetarianism or veganism, the abstinence from eating meat or animal-based products, respectively, are two trends that have become increasingly popular over the last twenty years. Extrusion processing allows for the manufacture of direct expanded snack products and plant-based meat alternatives, specifically high moisture meat analog (HMMA) products, and hence, offers excellent potential to respond to such diet changes. To improve the texture of snack products fortified with dietary fiber and the structure of HMMA products, interactions between the major food polymers, including starch, protein, and fiber, as impacted by extrusion processing, need to be understood. Therefore, this dissertation work focused on evaluating potential interactions between starch and fiber during the production of direct expanded products, as well as on the interaction between proteins during protein texturization. Generally, the inclusion of insoluble fiber into direct expanded starch products causes an undesirable reduction in expansion. Potential interactions between starch and fiber were evaluated by the traditional approach of analyzing the raw and the extruded materials using wet-chemical and spectroscopic techniques further by two novel approaches, including the 1H NMR analysis of model compounds representing the complex biopolymers starch and fiber and a simulated small-scale expansion process using a newly developed pressure vessel setup. Even though it has often been assumed that fibers are inert during extrusion processing, the results suggest that starch and fiber interact through hydrogen bonding; however, there was no evidence for covalent bonds formed between the biopolymers during extrusion processing.Despite the extensive conducted work on understanding the mechanism of protein texturization, it is still not fully comprehensive as to why proteins from some plant sources perform better than others. With a focus on disulfide bonds, which are often described as essential during protein texturization, interactions between proteins were analyzed using different techniques, including spectrophotometric measurement of disulfide bonds, solubility tests, and polymeric protein extraction followed by size exclusion chromatographic analysis. The findings indicate that large disulfide linked polymers are formed during HMMA extrusion processing and that the mechanism of texturization differs slightly based on the protein source. Additionally, it was found that reducing agents can help form a fibrous texture by premature splitting of existing disulfide bonds, better protein alignment, and improved flow characteristics
An Examination of Discordance in Suicidal Ideation Disclosure & Identification for Those Experiencing First Episode Psychosis
Full text linkBackground: People with first episode psychosis (FEP) are more likely to die from suicide than the general public. Coordinated specialty care (CSC) programs are early intervention programs for those experiencing FEP. CSC programs are associated with improved patient outcomes and recommended by the Center of Disease Control and the National Institute of Mental Health. Despite these benefits, suicide reduction in CSC programs has been limited. One key step in preventing suicide is screening for suicidal thinking and behavior. Consistent with the principles of measurement-based care (MBC), regular assessment of suicidal thinking and behavior is the first step in reducing suicide in CSC patients. This thesis explores factors associated with the discordance between self-reported and clinician-rated suicidal ideation during CSC treatment, with the goal of improving the way suicidality is assessed in CSC programs.Methods: First, a secondary data analysis of CSC program’s concordance and discordance of patient and clinician-reported suicidal ideation was documented. Predictors of discordance, such as clinician-rated symptoms of psychosis, self-reported symptoms of psychosis, hospitalizations, and living situation were identified. Simple and multiple linear regression models were used to examine the association between the suicidal ideation measures of the 107 individuals who had received services through New Journeys (service users) and clinical, functional, and demographic variables (e.g., symptoms of psychosis, age, living situation). To further explore challenges to assessing suicidal ideation in CSC programs, 19 qualitative interviews were conducted with current and previous CSC practitioners. Interviews were conducted and analyzed using reflexive thematic analysis.Results: Discordance occurred with 48% (n=51) of service users. In the backwards stepwise regression model, clinician-rated symptoms of hallucinations (B=.061; SE=.026) and delusions (B=.066; SE=.032) were significantly associated with discordance between suicidal ideation measures (p=.002). No other variables were independently associated with discordance. Qualitative analyses identified three main themes related to the identification of suicidal ideation in service users: service users, family members, and practitioners. Each theme had subthemes that influenced the effectiveness of suicidal ideation identification in the themes.Conclusion: Discordance between measures of service use and clinician suicidal ideation are frequent in CSC programs and presents a problem for suicide prevention. Higher levels of psychotic symptoms were associated with increased likelihood of discordance. Strategies for improving screening of suicidality, especially in service users with more severe symptoms is needed. Qualitative results suggest that family members may be an untapped resource for identifying suicidality in service users
Potential Economic Losses from Planting Nonuniform Seed Lots and Improper Seed Sizes for Three Potato Varieties
Full text linkQuality seed of the ideal size and type (i.e., whole-seed tubers or cut seed pieces) is a critical component of achieving uniform plant stands which optimize economic returns in commercial potato production. Nonuniform emergence from Clearwater Russet is common in the Columbia Basin of Washington but not well understood. To gain a better understanding of the issue, a survey assessed performance of commercial seed cutting operations during 2021 and 2022. The average seed piece sample contained 23% 3.0 oz. Eleven percent were obvious chips weighing 3% per acre. We conclude that growers should target the seed sizes listed above and minimize under- and oversized seed pieces to produce the highest economic return for each variety
PROBING THE ROLE OF ZINC-ZIRCONIUM MIXED OXIDE AS SUPPORT IN SINGLE ATOM CATALYSIS
Full text linkSingle atom (SA) catalysis, a leading field in catalytic research, excels in efficiency and minimizes metal use. The effectiveness of single atoms is linked to their dispersion on support materials. Choosing the right support is vital due to the tendency of single atoms to aggregate. Metal oxides are favored supports for their simple synthesis and versatility. However, using a single metal oxide limits dispersion and performance. Blending different metal oxides, like ZnO and ZrO2, creates more diverse binding sites and adjustable SA-support interactions.We have synthesized various ZnO–ZrO2 compositions via co-precipitation method, forming solid solutions due to their compatible crystal structures. We have used X-ray diffraction, X-ray fluorescence, gas adsorption, and other spectrometric techniques to investigate the limits of solid solution formation allowing us to pinpoint the optimal ZnO–ZrO2 composition for SA catalysis. In one project, we anchored palladium (Pd) ions to our mixed oxide, resulting in a controlled Pd integration. The atomically dispersed states of the Pd atoms on the ZnO–ZrO2 support was confirmed by X-ray absorption. Using this ZnO–ZrO2 supported Pd catalyst (0.06 wt%) in carbon-carbon coupling (Heck) reactions, we have achieved over 99.9% conversion, high yield, and good selectivity at 85°C in an environmentally friendly ethylene glycol-water mixed vsolvent system. We also anchored copper (Cu) to the ZnO–ZrO2 support, using this Cu catalyst (3.4 wt%) for azide-alkyne Click reactions. Operating under eco-friendly conditions using an ethylene glycol-water mix as the solvent media, we observed >99.9% conversion with excellent yield and selectivity. Moreover, with minimal Cu leaching, this catalyst was efficiently recycled through simple centrifugation, demonstrating its robustness and reusability. In conclusion, our study presents a novel approach for controlled metal loading on supports using mixed metal oxides, demonstrating significant catalytic efficiencies in Heck and Click reactions
CTMC example simulations and datasets
No full textThe compressed tarball archive contains the complete simulations of the simple 1-, 2-, and 3D continuous time Markov chain (CTMC) examples from "Representing Uncertain Solute Transport in Porous Media with Continuous Time Markov Chains" and the necessary datasets and scripts to generate the plots from the 2D and 3D heterogeneous velocity examples. The archive contains 3 Matlab m-file scripts and two .mat datasets.</p
Physicochemical Characterization and Treatment of Wildfire Ash Particles in Drinking Water
Full text linkWildfires activity is increasing in many regions globally due to climate change and accumulated fuel loads. Wildfires often accelerate post-fire erosion and increase turbidity resulting in shifts in surface water quality. Forested watersheds provide potable water supplies for billions of people around the world. Understanding the properties of wildfire ash that drive particle stability, downstream mobilization in aquatic systems, and the effects on drinking water treatment are crucial for effective post-fire management and treatment of water sources. Wildfire ash samples were collected from 2020 Oregon and California fires and compared to unburned soils. Ash was also produced under laboratory conditions. To understand the impacts of wildfire ash particles on source water quality and drinking water treatment, three studies were conducted: 1) characterization of physicochemical properties of different color wildfire ash, 2) comparison of wildfires ash and lab-produced ash water quality effects and particle stability in different water chemistries, 3) conventional coagulation treatability study of wildfire ash and lab ash particles. Particle size, specific surface area, pH, electrical conductivity, turbidity, alkalinity, zeta potential, dissolved organic carbon (DOC), nutrients and optical properties were analyzed. Analyses of solids showed lighter colored ash (white and gray), indicative of greater combustion temperatures, had higher pH, electrical conductivity, specific surface area, and zeta potential, and smaller particle size than darker ash (dark gray and black) and unburned soils. In different background water chemistries, white wildfire ash and 650 ℃ lab ash had the highest initial turbidity, but settled faster compared to dark wildfire ash and low temperature lab ash. Leached organic carbon and nitrogen concentrations were the greatest for dark gray ash and 250 ℃ ash, and lowest for white ash, 650 ℃ and unburned soils. Among all ash-water mixtures, white ash showed the highest zeta potential (-27.4 ± -7.80 mV) suggesting higher particle stability. All ash samples had higher zeta potential than unburned soils. Results indicate post-fire source water may contain more stable particles and increased organic matter. The treatability evaluation showed that 250 ℃ lab ash was the least amenable to coagulation at all alum doses (20, 40, 60, 80 mg/L) resulting in lowest turbidity and DOC removal while 650 ℃ lab ash showed the greatest removal among all ash samples. White wildfire ash also required a higher alum dose (60 mg/L) than unburned soils (40 mg/L) to reduce zeta potential to -5 mV. pH adjustment of ash-water mixtures resulted in significantly lower finished water turbidity and DOC at an alum dose of 20 mg/L implying post-fire source water may be treated with conventional processes if pH is adjusted. Water providers who experience wildfires and degraded source water quality from ash may need to increase coagulant doses and lower pH to reduce turbidity, zeta potential, and DOC effectively.
1-MCP Inhibition of Ripening in ‘D’Anjou’ Pears Biochemical Characterization and Ripening Solutions
Full text linkChanges in global climate patterns will continue to stress food production and distribution far into the future. In fruits, early ripening, and associated processes such as flesh softening, and starch-to-sugar conversion are major causes of food wastage post-harvest. One means of combatting food wastage, especially in vulnerable crops such as climacteric fruit, is to delay the onset of ripening. Perhaps the most powerful tool for this effort is the 4-carbon gaseous molecule 1-methylcyclopropene (1-MCP), which inhibits perception of the “ripening phytohormone” ethylene. Delaying ripening by 1-MCP treatment allows distributors to extend storage and transportation times and researchers to investigate the molecular physiology of climacteric fruit ripening at increasingly granular levels. However, 1-MCP effects in European pears (Pyrus communis) yield perplexing results, with fruit often failing to ever ripen after treatment. To preserve this valuable chemical treatment tool, research has identified a putative ‘ripening compound’ glyoxylic acid (GLA) as a chemical means of restoring ripening competency in 1-MCP treated winter pear varieties such as ‘D’Anjou’. Physiological investigations reveal that peak ethylene evolution is up to two-fold higher and terminal flesh firmness is lower, on average 1 lbs-force in 1-MCP + 3% (w/v) GLA treated fruit over 1-MCP only fruit. GLA-treated fruit also respire on average 450 µg CO2 kg -1 hr -1 more than their 1-MCP only counterparts in 4oC cold storage though there are no discernable differences in endogenous organic acid pools between the two treatments. Brown necrotic spots visible on GLA-treated fruits are likely due to lipid peroxidation, as the occurance of lipid hydroperoxides is up to 30% higher in GLA-treated fruits. Previous research using 1-MCP treated fruit obtained from packing houses and stored in different stroage conditions than this study has proposed that GLA is metabolized via malate synthase in the glyoxylate pathway. In this study, where precise quantifiable application of 1-MCP was used without prolonged storage, no increase in enzyme activity could be observed in vitro after GLA treatment. Furthermore a novel cost effective method of 1-MCP application is documented allowing for accurate application of the ripening inhibitor for small scale research down to 50 parts per billion
Advancing Optical Spectroscopic and Chemometric Approaches to Solve Key Analytical Challenges in the Nuclear Fuel Cycle
Full text linkTo close the nuclear fuel cycle, innovative work in the development and scaling up of spent fuel recycling schemes is necessary. Spent fuel and legacy waste reprocessing must be undertaken and processing efforts accelerated to reduce current inventories of material in interim storage and to improve the environmental sustainability of nuclear reactor fuel production. This work contributes to the growing body of research dedicated to the demonstration of optical spectroscopy as a robust, trusted tool for real-time monitoring and characterization of chemical systems in the nuclear fuel cycle. Specifically, this work focuses on promoting the reduction of grab sampling from radioactive material process streams in three ways. Firstly, by providing real time data for chemical systems, on-line monitoring has been demonstrated to reduce the required number of grab samples required to maintain safeguards standards. A major challenge for optical absorbance techniques during process monitoring is the acquisition of a stable spectral reference. The analysis of single-beam spectra for the prediction of lanthanide concentration is explored under instrumental conditions causing tenfold changes in incident light for the optical measurements, and robust linear models are produced from these unreferenced, visible range spectra. This method promotes the use of single-beam spectroscopy as a real-time measurement tool even in on-line, hazardous, and physically inaccessible systems, such as those found in nuclear fuel reprocessing or legacy waste processing.Secondly, the use of optical spectroscopic techniques for measurement on microfluidic devices (MFDs) is explored. MFDs require much smaller sample volumes compared to traditional optical measurement cells, and therefore their increased use in nuclear material characterization could reduce the required volume for grab samples.Thirdly, the use of sensor fusion can provide increased quantitative and qualitative information from a single sample. Sensor fusion involves the application of multiple measurement methods simultaneously to a single sample; the data streams from each method may be analyzed separately or together. In this work, up to three nondestructive optical techniques, Vis and NIR absorbance and Raman spectroscopy, are utilized to interrogate lanthanide and actinide samples. By combining spectral data streams, quantitative errors of prediction are improved and trends in speciation are revealed.The overarching goal of this work is to advance chemometric data analysis of optical spectra in challenging measurement systems, analyzing chemically complex samples on the microfluidic scale and under measurement scenarios encompassing substantial spectral variance. The multivariate analysis schemes developed here focus on analyzing three datasets of f-element solutions using multiple chemometric techniques to derive both qualitative and quantitative information for enhanced characterization of the target systems. It lays the groundwork for future applications of optical spectroscopic techniques on the next generation of microfluidic platforms and for deployment of optical spectroscopic techniques in challenging on-line monitoring scenarios
COMPACT, FREQUENCY RECONFIGURABLE RADIO FREQUENCY INTEGRATED CIRCUITS FOR ENERGY HARVESTING AND COMMUNICATIONS
Full text linkThis dissertation investigates the design and development of compact, frequency-reconfigurable RFICs engineered for two primary objectives: efficient energy harvesting and robust wireless communication. The research involves on developing circuits that can be frequency tuned to target multiple frequency bands. Such reconfigurability is critical for operating across multiple frequency bands, enhancing energy efficiency, and ensuring optimal performance. By enabling these circuits to adjust in real time, the work contributes to better utilization of scarce spectral resources, making the systems more versatile and capable of functioning in a broader range of scenarios. The key contributions of this dissertation are focused on: dual-band energy harvesting for wireless power transfer applications in ISM bands, triple-band oscillator design in K-Ka band, and strong interference cancellation in the L-band. There could be numerous applications of the techniques developed in this work, some of which are demonstrated here in this dissertation. Few more applications and suggestions for future research directions based on the proposed work are also outlined here