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The Maiden’s Tower of Femininity
Get PDFThis paper examines portrayals of femininity within “Maiden in the Tower” tales. It analyzes the means by which maturation, sexuality, reproduction, and female agency contribute to the shaping of femininity. Via Petrosinella by Giambattista Basile, Rapunzel by the Brothers Grimm, and Tangled by Disney, the paper explores how variations portray historically unique interpretations of ideal, female traits that defy common assumptions. The evolution of perspectives across “Maiden in the Tower” tales help us grasp how gender ideologies are communicated and how women are socialized
Ion Current Analysis And Misfire Prediction During Cold Start In A Compression Ignition Engine
Get PDFIn future, compression ignition engines are anticipated to continue powering heavy-duty trucks and certain machinery, while passenger vehicles and light-duty vehicles will increasingly be battery powered. However, compression ignition engines face challenges such as combustion instability, misfiring, and high unburnt hydrocarbon emissions when started under severe cold conditions. These issues can be mitigated through the use of real-time feedback to the engine\u27s control module.
The ion current signal, reflective of combustion and emissions characteristics, has proven to be a reliable feedback signal under warmed-up conditions. In this dissertation, the potential of the ion current signal as a feedback mechanism during cold start and cold idling was investigated. To study the ion current signal, cold starting experiments were conducted using ULSD in a VW’s 2.0-liter, direct injection, 4-cylinder compression ignition engine at ambient temperatures of -10 ⁰C, 0 ⁰C, 10 ⁰C, and 20 ⁰C. It was observed that at lower ambient temperatures, the ion current peak could sometimes be too small and disguise as noise. In some misfiring cycles, the ion current was detected even though the pressure trace did not exhibit a combustion event, indicating that autoignition occurred but combustion failed to sustain. In firing cycles, an ion current characteristic could reasonably predict combustion phasing at higher ambient temperatures. These findings suggest that the ion current signal could provide valuable feedback to mitigate cold-starting problems in compression ignition engines.
Un-sustained combustion in some engine cycles can be attributed to poor equivalence ratio distribution in the fuel-air mixture. Hence, a novel methodology was developed to evaluate whether the quality of the fuel-air mixture is sufficient to sustain combustion and prevent misfiring. This methodology is based on 3D CFD simulations of fuel spray and does not require chemical kinetic calculations. As a result, its key advantage lies in its computational cost-effectiveness, while it also takes the engine geometry into consideration. However, this methodology is semi-empirical, as it relies on insights from a separate set of cold starting experiments conducted in the same engine. ULSD was utilized in these experiments as well, and a two-injection strategy was deployed at an approximate ambient temperature of 22.5 °C, a condition under which the glow plug remained inactive. The key insight gained was that the engine misfired when the fuel-air mixture from the pilot injection became too lean or did not have enough time to autoignite before merging with the main fuel-air mixture. Therefore, the methodology evaluates whether the quality of the pilot fuel-air mixture and the time it requires to autoignite are above certain thresholds determined in this work. Lastly, the methodology was observed to fall short when the glow plug was active in a cold-starting experiment. Hence, a modification to the methodology was proposed that would be effective whenever the glow plug is active. Although ULSD was utilized to develop the methodology, it can be adapted for low-carbon intensity fuels such as renewable diesel, hydrogen, biodiesel, etc., which are poised to be the fuels of the future
The Political Economy Of Police Chief Selection
No full textABSTRACT
THE POLITICAL ECONOMY OF POLICE CHIEF SELECTIONby ADAM UDDIN MAY 2024 Advisor: Dr. Kristin Taylor Major: Political Science Degree: Doctor of Philosophy Although the topic of police chief selections has been investigated, the factors that influence the decision to select a police chief have not. This dissertation examines what factors may influence executive decision making in the context of police chief selection decisions in Detroit Michigan from 2008 to 2021. The primary factors of interest to explain police chief selection decisions for this research are police chiefs were hired because of politics, merit or professionalism. During this time Detroit had experienced high violent crime, multiple scandals involving the police chiefs under study and the filling of the largest municipal bankruptcy in United States History. By combining evidence gathered from a mixed methods longitudinal study using a comparative case study approach, content analysis, and theory testing, this dissertation demonstrates that political factors impact a mayor’s decision to select a new police chief. Ultimately, police chief selection decisions do not happen in a vacuum but in a political context specific to the circumstances before and during the selection process. This research expands upon the role of key factors influencing a mayor’s decision to select a new chief of police
Examination Of The Impact Of Work-Related Stress On Job Satisfaction Among Correctional Officers Working In Massachusetts And Texas State Prisons
No full textThis research provides a detailed analysis of the impact of work-related stress on job satisfaction among correctional officers working in Massachusetts Department of Corrections (MADOC) and Texas Department of Criminal Justice (TDCJ) prisons between 2017 and 2018. Other salient predictors of job satisfaction were controlled for as well in order to determine which factors had the greatest impact on job satisfaction among correctional officers in this study. Additionally, MADOC and TDCJ were analyzed together and separately. Here, this study shows that demographic variables were not predictors of job satisfaction. Instead, job satisfaction was best predicted by officers’ level of commitment to the organization and their levels of work-related stress. This research is helpful for correctional supervisors and administrators that want to increase job satisfaction, decrease turnover, and keep staff and inmates safe and secure
Desmitificación Del Personaje Migrante Mexicano Visto Como Delincuente En Estados Unidos En Novelas Contemporáneas Escritas Por Autores Mexicanos
No full textDESMITIFICACIÓN DEL PERSONAJE MIGRANTE MEXICANO VISTO COMO DELINCUENTE EN ESTADOS UNIDOS EN NOVELAS CONTEMPORÁNEAS ESCRITAS POR AUTORES MEXICANOS
by
JESÚS CONTRERAS BAZALDÚA
May 2024
Advisor: Dr. Hernán GarcíaMajor: Modern Languages (Spanish) Degree: Doctor of Philosophy This dissertation analyzes literary representations of male migrant characters of Mexican origin who legally or illegally enter the United States throughout the 20th century and the first decades of 21st century. The purpose is to examine the stereotype of the Mexican migrant seen as a criminal once they step foot on American soil in the following novels written by Mexican authors: Las aventuras de don Chipote, O cuando los pericos mamen (1928) by Daniel Venegas, Murieron a mitad del río (1948) by Luis Spota, the short story “La pena” included in the novel La frontera de cristal (1995) by Carlos Fuentes, and Campeón gabacho (2015) by Aura Xilonen Arroyo. The different historical events between Mexico and the United States such as the loss of Mexican territory after the signing of the Treaty of Guadalupe Hidalgo in 1848, the need for cheap labor in the United States during World War II, the creation of border control institutions like the Border Patrol, the massive deportation of undocumented Mexican workers, among others, created over time the perception that Mexicans are inferior, poor, dirty, useless, disposable, harmful, and undesirable beings, to the point of equating the Mexicans as criminals. The descriptions of the rogue character included in the picaresque novel as someone trying to satisfy basic needs or the young man who seeks to find the meaning of life in the bildungsroman help to decipher the internal and external processes the Mexican migrant characters face in their attempt to work, survive, and be included in American life
Instrumentation And Methods For Clinical-Scale Production Of Parahydrogen-Based Hyperpolarized Contrast Agents For Molecular Imaging
No full textUnderstanding the molecular transformations that underlie many diseases meansmonitoring the changes through metabolic pathways at the biomolecular level. Molecular imaging techniques such as MRI, positron emission tomography (PET), and mass spectrometry (MS) have become an indispensable tool for this purpose where compounds that are involved in metabolic pathways of certain diseases are detected and mapped. Of such techniques, MRI has the advantage of being non-invasive and non-destructive since it relies on the use of magnetic fields, radio waves and the inherent spin of nuclei in molecules to create images of tissues. However, MRI sensitivity is linearly proportional to the nuclear spin polarization (P) of the target nucleus. P is very low (10-5) at room temperature and clinically relevant magnetic field of 3T. Hyperpolarization techniques have been introduced to solve this problem by transiently increasing nuclear spin polarization using chemical and/or physical techniques which can then be used for enhanced molecular imaging as novel contrast agents. Among such techniques, Parahydrogen-Induced Polarization (PHIP) and Signal Exchange By Reversible Exchange (SABRE) and their variants offer a faster and cheaper alternative for production of hyperpolarized (HP) compounds that can be employed as metabolic contrast agents. These hyperpolarization techniques increase P by the addition of parahydrogen (p-H2) to a suitable substrate in hydrogenative PHIP or by reversible exchange with the substrate in the presence of a catalyst in SABRE. The result is an increase in nuclear spin order of protons in the target molecule which can also be transferred to heteronuclei X (13C, 15N, 31P) through spin-spin couplings using ultralow (\u3c1 microtesla) static magnetic field. The transfer to heterenuclei is necessary to achieve longer relaxations times (i.e., the lifetime of hyperpolarized state), which is crucial to the clinical translation of the technique. The main goals of this work are the development of 1) the semi-automated clinical-scale parahydrogen generator; 2) the automated degaussing circuit for microtesla regime hyperpolarization; 3) automated and integrated microtesla hyperpolarizer; 4) novel contrast agents using parahydrogen-based SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) and magnetic field cycling (MFC) techniques. Achieving these aims will help in the biomedical translation of new contrast agents for molecular imaging
The Effects Of Air Pollution On Health Of Underserved Populations: A Case Study Of Detroit.
No full textThe health consequences of air pollution represent a contemporary epidemic that affects poor communities disproportionately. The impact of air pollution on respiratory health as well as cardiovascular diseases, the primary cause of mortality in US and the rest of the world (CDC 2023), is a matter of policy concern. Previous research has established a robust correlation between air pollution and health. Less is known about whether air pollution has a compounding effect on health outcomes in medically underserved and socioeconomically vulnerable communities. This study utilizes the 2019 shutdown of the Detroit incinerator, a significant local pollution source, to evaluate its impact on respiratory and cardiovascular health of the neighboring residential population. We use a classic two-way fixed-effect design to evaluate the effects of air pollution on cardiovascular health of nearby population. We look at cardiovascular health related emergency department visits of vulnerable population living within a certain distance to the Detroit incinerator before and after its shutdown. To delve deeper, we stratify this population based on age, gender, and race, aiming to explore how air pollution impacts cardiovascular and respiratory health across demographic variations. Distance effect is also studied in this paper by creating 2 miles bands to evaluate the proximity to the incinerator. The closure of the Detroit incinerator resulted in a reduction of emergency department visits among the socioeconomically vulnerable and medically underserved population
Dynamitic Reading: Suspicion, Sociology, and Urgency in Ida B. Wells’s Antilynching Campaign
No full textInspired by an exchange between antilynching reformers Ida B. Wells and Jane Addams, this article uncovers a debate about reading methods—and the utility of reading suspiciously for marginalized groups—that occurred over a century ago. Responding to an opinion piece Addams wrote for The Independent in 1901, Wells delineates the limits of sympathetic approaches to the lynching crisis. Reading both Addams and Southern lynchers suspiciously and supplementing her readings with a new sociological tool, crime statistics, Wells demonstrates that lynchings of Black men were economically motivated. She develops her suspicious reading specifically to disrupt the bigoted sociology of race that fueled prolynching propaganda. However, she also sought better possibilities for the young social science discipline, advancing a sociology that analyzes the roots of Black oppression. Critics like Rita Felski have condemned the ubiquity of suspicious reading, which they associate with a distanced critical posture. At the same time, critics like Caroline Levine and Autumn Womack are leaning toward sociological methods. Unlike the adversarial mode typically associated with suspicious reading, Wells models an urgent suspicious reading that is deeply invested and, in her own words, “dynamitic.” For Wells, dynamitic reading helpfully intervenes against both the purported scientific objectivity of fin-de-siècle sociology and the indiscriminate affection of Addams, herself a sociological practitioner. It can also counter the inertness of now routinized critical practices. Wells provides us with a newly useful hermeneutics of suspicion. Moreover, she helps us to historicize and unpack the long relationship between sociology and literary studies
Perspectives in Embodiment Theory: An Introduction
No full textThis special issue of Human Biology, titled “Perspectives in Embodiment Theory,” brings together researchers who use a variety of lenses within the field of human biology to celebrate the plurality and wide applicability of embodiment. This special issue works to cross disciplinary boundaries to create more nuanced understandings of embodiment, plasticity, and experience in humans