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Statistical Investigation of Gypsum Crystallization Kinetics
Get PDFGypsum, a naturally occurring mineral salt, is frequently encountered in industrial processes such as seawater desalination and power plant cooling. Over the years, significant effort has been devoted to controlling the crystallization of gypsum through various chemical approaches, including acidification, chelating agents, and antiscalant polymers. Nevertheless, the cost associated with chemical treatments may be reduced by incorporating physical operational strategies to complement chemical methods in regulating gypsum crystallization.
This study systematically examines the comparative roles of chemical and physical entropy in the gypsum crystallization process to elucidate their respective influences on gypsum growth kinetics. Chemical entropy is manipulated by adjusting the saturation index of gypsum within the reactor, while physical entropy is controlled by varying the mixing intensity. First, we evaluate the accuracy of gypsum growth quantification using optical and electrical measurement techniques. Then, the variability among triplicate crystallization reactions is assessed across different saturation indices and mixing intensities. Finally, statistical analyses are performed to investigate the effects of these parameters on the reproducibility of gypsum crystallization under diverse conditions.
The findings reveal that although the gypsum crystallization process exhibits elements of stochastic behavior, chemical entropy exerts a substantially greater influence than physical entropy on overall reaction kinetics. These results provide valuable insights into the controllability of gypsum crystallization, identifying both promising opportunities and limitations for developing more efficient industrial processes involving the concentration of natural waters
Beyond Chromatin Insulator Function: Analysis of Drosophila BEAF-32 Activation of Core Promoters and Its Interaction with Transcription-Associated Factors
Get PDFEnhancer-promoter communication regulates spatiotemporal gene expression fundamental to the development of metazoans and the cell-lineage-specific transcriptional responses to extrinsic signals. These interactions can occur over large distances. However, it remains unclear how enhancer-promoter specificity is established. Several mechanisms have been proposed, including dividing chromosomes into chromatin domains separated by insulator elements that limit enhancer-promoter interactions to their resident domains. These domains can be seen as topologically associating domains, or TADs, by methods such as Hi-C. The insulator-binding protein BEAF-32 is the most predominant DNA-binding protein at Drosophila TAD boundaries. These inter-TAD regions contain active housekeeping genes. Consistent with this, BEAF-32 usually binds near transcription start sites of housekeeping genes. This raises the question of whether BEAF-32 plays a role in gene activation in addition to having an insulator activity. We approached the question in two ways. First, we sought to identify transcription-associated proteins that BEAF-32 directly interacts with. We investigated direct physical interactions and how common it is for these interactions to reflect an ability to communicate from a distance with BEAF-32, focusing on potential interacting partners FACT histone chaperone subunits Dre4 and SSRP and transcription factors DREF, Rib, and ROW. We provide evidence of BEAF-32 direct interaction with these proteins and show it can loop with SSRP and ROW. Second, we investigated BEAF-32 preference for housekeeping promoters over regulated promoters in its promoter activity. We interrogated fifteen housekeeping promoters plus four mutant variants, and fourteen regulated promoters plus four DSCP (Drosophila synthetic core promoter) derivatives. BEAF-32 activates all the housekeeping promoters assessed and certain regulated promoters containing only Inr. Two promoters lacking known motifs were also activated. Regulated promoters containing TATA-box, Inr-MTE, Inr-DPE, and Inr-MTE-DPE were not activated. Importantly, our data suggests that BEAF-32 is not just involved in helping to specify domain boundaries, but also is directly involved in regulating gene expression
The Impact of Visual Stimuli and the Properties of Green Walls on Human Well-Being in Built and Immersive Virtual Environments
Get PDFThe built environment significantly influences human well-being, particularly in the context of stress recovery and cognitive restoration. This dissertation investigates the impact of visual stimuli, particularly green walls, on human responses related to stress, restoration, and thermal comfort. The research is guided by three primary objectives: (1) examining the role of visual stimuli and their properties in promoting stress recovery and restoration, (2) evaluating the potential of Immersive Virtual Environments (IVEs) as tools for delivering and studying restorative environments, and (3) investigating the influence of green walls on indoor environmental conditions.
A series of experimental studies were carried out to achieve these objectives. The preliminary pilot study examined how various natural objects and their visual properties influence attention within both real and virtual office environments. Eye-tracking technology was employed to measure participants\u27 attention and identify the properties that attract attention and potentially contribute to restoration. The findings highlighted the importance of natural objects in capturing attention and suggested that certain properties, such as size and location, play a significant role.
Subsequent studies focused specifically on green walls, examining their size, presence, and environmental effects. One study investigated the impact of varying green wall sizes in virtual environments on participants\u27 stress recovery and restoration. The results revealed that the size of the green wall did not significantly influence restoration outcomes, suggesting that the restoration process may be conceptual in nature and not strictly dependent on the intensity or size of the visual stimuli. This insight has practical suggestions for the design of restorative environments in spaces with physical limitations.
The dissertation also compares the restorative effects of real and virtual green walls, providing insights into the potential of IVEs to simulate nature\u27s benefits. Findings indicated that while virtual green walls can elicit similar physiological and psychological responses to real ones, differences emerged over time, with the virtual exposure losing some of its restorative efficacy. This pattern underscores the need for further investigation into the temporal dynamics of virtual exposure.
Finally, the research explored the impact of green walls on indoor temperature and humidity. Results showed that the green wall contributed to increased humidity and minor temperature variations, suggesting a potential role in passive climate regulation.
The results of this research enhance the broader understanding of biophilic design and highlight the potential of IVEs in studies on restorative environments. The dissertation concludes with practical design recommendations and future research directions focused on exploring different visual properties, enhancing methodological approaches, and applying advanced data analysis techniques, such as machine learning, to model restorative responses in real and virtual settings
Catholics in Name Only ?: Weimar Catholic Identity and the Thought of the DNVP Reich Catholic Committee
No full textSince the Kulturkampf in the 1870s, the Zentrum party had served as the primary political vehicle for German Catholics interests. Although the Zentrum had long gathered German Catholics of various classes and ideological dispositions under its confessional-political umbrella, the party’s decision to ally with the Church-hostile Social Democrats in the first coalition after the November Revolution and to support the revolution’s offspring, the Weimar Republic, caused consternation among its right wing. Believing that the party could no longer justifiably claim to represent German Catholicism, some conservative Catholics defected from the Zentrum and found a political home in the Reich Catholic Committee (RKA) of the recently established, majority-Protestant Deutschnationale Volkspartei (DNVP). Under fire from their fellow Catholics in the Zentrum, the RKA had to persuade their brothers and sisters in faith that the Zentrum could no longer justifiably claim the title of the sole political representative of German Catholicism and that the DNVP’s program more closely adhered to Catholic political and social theory. To have any hope of drawing Catholics away from the Zentrum and into the arms of the DNVP, the RKA needed to associate German Catholic identity with conservative politics. Their efforts led to the development of a conservative Catholic political theory that affirmed monarchical rule, critiqued modern economic ideologies like socialism and capitalism, idealized the German nation, and challenged the secularization of public life. Following the committee from its inception in October 1920 to its first dissolution in the Summer of 1929, this dissertation analyzes the worldview and rhetoric of the RKA to illustrate that the conflict between the Zentrum and the RKA over who truly represented German Catholic identity in the Weimar Republic was more than a party-political dispute, but another front in the decades-long battle within Catholicism over the relationship between the Catholic faith and modernity itself
Extraction of Lignin Using DES: Effect of Heating Methods and Process Design
No full textLignin stands out as a potential, renewable resource for the sustainable manufacture of aromatic chemicals, which provides a viable alternative to petroleum-based products. Despite its vast potential, the use of lignin is limited due to the unwanted effects of certain extraction/isolation processes on its quality and structure. The goal of this study is to investigate the application of a continuous process in the extraction of lignin using microwave irradiation and DES. To also study the feasibility of a large-scale lignin extraction process using DES and conventional heating methods, comparing the physicochemical characteristics of the lignin extracted with that of commercial lignin. Lignin was extracted on a large-scale using DES at two temperatures (80 and 100 ℃) and a constant residence time of 4 hours. Two different lignin (AL & DL) were obtained from the study. The sample AL had better purity than the DL and commercial lignin samples. The AL samples were also lighter in color and showed less occurrence of repolymerization reactions. As the temperature increased, the yield of the lignin samples also increased. The continuous extraction of lignin was carried out at four different temperatures (60, 70, 80, and 90 ℃) and flow rates (108, 141, 173, and 207 ml/min). The lignin yield increased with an increase in temperature and residence time. At 80 ℃, a higher lignin yield was obtained with good properties, therefore, 80 ℃ was chosen as the critical temperature for the process. A kinetic study was also carried out, and the activation energy of the process was recorded as 107 KJ/mol. A numerical model studying the continuous microwave heating of the reactant mixture was developed using COMSOL Multiphysics. The model was in good agreement with the experimental results, and the configuration of the reactor was found to influence the microwave heating of the reactant samples. Additionally, a parametric sensitivity analysis was carried out and showed that mild changes in the relative permittivity influence the microwave heating of the DES: biomass mixtures. These studies help to advance the understanding of lignin extraction using microwaves and DES, it also helps the commercialization of lignin extraction using DES for further valorization. The model developed can be used to simulate and optimize the continuous extraction of the lignin using microwave
Desired Student Learning Outcomes for Middle School Agricultural Education: A Modified Delphi Study
Get PDFMiddle school agricultural education programs across the U.S. have continued to increase, but modern systems have failed to provide support for the preparation of middle school agricultural education teachers. For instance, middle school teachers have expressed concern regarding the development and implementation of middle school agricultural curriculum. In response, this investigation sought to identify learning outcomes related to agricultural content, technical skills, and career readiness for middle school agricultural education. A modified, three-round modified Delphi study was used to identify these learning outcomes. The expert panelists consisted of 19 middle school agricultural education teachers who completed a teacher certification program and provided instruction exclusively to students in grades five through eight. In total, 145 learning outcomes achieved a consensus level of agreement of 75% or greater. Expert panelists came to consensus on 71 agricultural content topics which were categorized into 10 AFNR pathways, 19 agricultural technical skills which were categorized into eight AFNR pathways, and 54 career readiness skills which were categorized into eight themes. I interpreted the findings from this investigation using Roberts’ and Ball’s (2009) model for agricultural subject matter as a content and context for teaching, which supported these findings. It can be concluded that the expert panelists believed that agricultural content and skills should be emphasized in middle school agricultural education and that they preferred specific pathways when providing instruction. The expert panelists also valued career exploration over career preparation. As such, I recommend assessing preservice teacher knowledge of these learning outcomes to determine preparation levels. I also recommend reimagining agricultural education frameworks and proposing a new model with middle school agricultural education in mind
A multi-constraint Monte Carlo Simulation approach to downscaling cancer data
No full textThis study employs an innovative multi-constraint Monte Carlo simulation method to estimate suppressed county-level cancer counts for population subgroups and extend the downscaling from county to ZIP Code Tabulation Areas (ZCTA) in the U.S. Given the known cancer counts at a higher geographic level and larger demographic groups at the same geographic level as constraints, this method uses the population structure as probability in the Monte Carlo simulation process to estimate suppressed data entries. It not only ensures consistency across various data levels but also accounts for demographic structure that drives varying cancer risks. The 2016–2020 cancer incidence data from the Utah Cancer Registry is used to validate our approach. The method yields results with high precision and consistency across the full urban-rural continuum, and significantly outperforms several machine-learning models such as Random Forest and Extreme Gradient Boosting
Volatility characteristics and hyperspectral-based detection models of diesel in soils
No full textThis study developed an efficient method using hyperspectral camera for detecting diesel content in soils with spectral indices. Over 70 days of the experiment, clean soils were saturated with diesel, and 186 measurements were taken to monitor the evaporation rate and spectral variation. The diesel evaporation followed a logarithmic pattern, where the diesel volatility decreased from 1.57% per day during the initial period to 0.06% per day during the late period. Using the hull-quotient reflectance at 2236 nm, the diesel content prediction model derived from a stepwise multiple linear regression (SMLR) achieved satisfactory accuracy with sufficient statistical significance (R2 = 0.89, RPD = 2.52). This spectral band was well visualized for diesel presence in hyperspectral images as the band infers variations in two absorptions (CH/AlOH and CH) concurrently. Additionally, this study presented an age estimation model based on the diesel evaporation rate using the same spectral band. Given the fact that this study is based on the largest number of samples with the longest observation period and models were developed excluding atmospheric absorption bands, the simple form of the spectral index makes it applicable to large-scale diesel pollution detection with hyperspectral scanners or narrow-band multispectral cameras in real-world cases
Osteon Analysis and Health Status at the Colonial Maya Site of Tipu, Belize
No full textThis dissertation examines patterns of health disparities and inequalities as seen through a bioarchaeological lens of health defects and bone microstructure. Spaniards arrived in what is now known as Belize by 1544, forever changing the lives and health of the local Maya. A colonial mission site known as Tipu, located in modern-day central-western Belize, was occupied prior to, during, and following Spanish contact, and would become an important center for the indigenous Maya and Spaniards through the Colonial Period (AD 1519 onwards). This dissertation uses Tipu as a lens in which to understand the impact of colonialism on health and burial practices in the western Belize region. Bone histology and geographic information systems are used to assess the impact colonialism had on individuals inhabiting the Spanish colonial frontier in Belize. Rib fragments from 200 individuals were selected for histological analysis, results of which indicate that females, particularly females buried inside the church structure, had the highest annual rates of remodeling, indicating better health. When mapped, clear clusters of high and lower annual rates of remodeling are present. Additionally, a holistic health metric was designed for Tipu burials, and 466 individuals were mapped according to their health status scores. Results of these maps were strikingly similar to those made from annual rates of remodeling. When annual rates of remodeling were compared to health metric scores, the relationship was inconclusive and necessitates further research. This dissertation argues that the colonial experience at Tipu varied according to factors like sex, occupation, status, and proximity to Spanish settlements, and that variability in any could account for drastically different experiences or health outcomes. My dissertation suggests that the colonial experience was a continuum both in how it was experienced by the indigenous populations, but also in how much was embodied into everyday life via health status and bone microstructure