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A Methodology For Determining Optimal Milling Parameters For Low-Taper Microtensile Sample Production
Get PDFFemtosecond lasers are beginning to see an increase in interest for industrial and high throughput microsample milling applications. Despite this, much of the literature regarding removal rate studies for ultrashort pulse laser milling continues to focus on single-pulse or similar experiments that have a very small time on target. The material volume removal rates of femtosecond milling can vary wildly depending on parameters like laser scan speed, hatch spacing, z-axis step size, and pulses on the material. Currently, there is no established methodology for determining the optimal values of these parameters for micromilling applications. This methodology was developed in this study. The methodology consists of a pulse study, a repeat study, and a z-step study that will return the milling parameters that resulted in the largest volume removal rate for the laser used for this research. The methodology was created for the laser system used in this study, and was tested on 316 Stainless Steel, but was developed in such a way that it may be adapted to any material, and with some tweaking of variables might be used in other laser systems. The laser system used in this study utilizes a novel positioning stage that introduces 6 degrees of freedom to the translation of laser samples, being able to tilt and move in all three axes. Using both the developed methodology and the unique capabilities of the laser microtensile samples were produced with taper angles of \u3c1° in 316 Stainless Steel
Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer
Get PDFSurface soil moisture retrieval from L-band brightness temperature has been developed for the past decades due to multiple beneficial characteristics of 1-2 GHz frequency bands for remote sensing of the environment. Numerous microwave emission models have been proposed for tower and satellite-based operations with successful retrieval of surface soil moisture and vegetation water content. As a result of the development of cost-effective and low-mass microwave L-band radiometers such as the Portable L-band Radiometer (PoLRa), surface soil moisture surveying traditionally developed by satellite missions SMOS and SMAP can now be developed at local scales, bringing these operations to commercial small unmanned aerial systems (sUAS) providing high detail resolution retrievals at low elevation (7 m or lower depending on canopy height). Due to its cost and limited access, low-altitude, sub-orbital L-band dual polarization radiometry operations for soil moisture retrieval still need further exploration. This study used an sUAS-mounted L-band radiometer and a multispectral camera to model surface soil moisture over irrigated alfalfa cropland in New Mexicoâ??s Rio Grande Valley. This setting allowed varying soil and vegetation moisture conditions, validating with commercial soil moisture probes. This work compared dual and single polarization algorithms using the single scattering Tau-Omega (Ï? -Ï?) model with a conventional dielectric mixing scheme, a semi-empirical HQN roughness model and NDVI derived Ï? to retrieve soil moisture. The calibrated high resolution (4.5 m footprint) dual-polarization retrievals presented superior accuracy for estimating ground truth moisture under dry conditions with RMSE values between 0.03-0.054 cm³/cm³, and 0.068-0.115 cm³/cm³ after irrigation. Horizontal polarization single retrievals performed favorably against vertical. This study identified improvements for commercial applications and highlighted the potential of sUAS to achieve competent soil moisture and vegetation water content retrievals in semi-arid lands for low canopy land covers
The Future of Robotics: An Advanced Ethical View of Robotics Contributing to Elderly Care, Medicine, and Workforce Participation
Get PDFIron Curtains: A Novel of Germany, 1989
No full textA work of fiction. A story of Love, Treachery, and Freedom on the East German border in 1989.Iron Curtains is a story of four individuals in East and West Germany brought together by an espionage investigation and the revolution in East Germany which led to the fall of the Berlin Wall and Iron Curtain on November 9, 1989. Their stories ultimately intersect as the year passes and culminate in an escape through a tunnel underneath the East German border. There are four main characters and several secondary characters who help drive the story forward by their interaction with the main characters. These main characters are: Augustina Hermosillo (Tina), a 21 year old rookie Counterintelligence Agent from Tucson. She’s arrived on a secret mission to investigate her boss, Nick, and finds herself in a tangled web of potential espionage. Her attraction to Nick and her desire to save him from his self-destruction gets in the way and, during their investigation of the suspect Markus Kaiser, they are led to a small little factory that sits just across the Iron Curtain, in a misty little river valley. They observe the factory from a hilltop on the west, and that’s where Tina, armed with a camera, see Hans sitting in his office in the factory. She feels his despair and is drawn to the idea of contacting him and helping him escape East Germany. Nick Torman – Tina’s Supervisor and tasked with training her, something he does not want to do. He’s a grizzled black operative, traumatized by a failed mission, taking the slow way out of life by drinking himself to death and flirting with the quick way out, his gun. He’s surprised by Tina suddenly in his life and the magic she’s having on him. He needs to protect her and heal. Nick is deeply involved in the twisted web Tina is investigating, and we don’t know how deep until the very end. Hans Jurgens – a retired East German Olympian, he has an office in the factory, but no responsibility, and he desperately wants to escape East Germany, taste freedom, and show them that they can’t possess him and his family. He has a mysterious connection with the falcon that lives on the hilltop in the West. In spite of his guilt for not contributing to the revolution, he’s being awarded a medal of high honor. Hans’ journey takes us through the landscape of the 1989 revolution in East Germany. Dieter Wolff - the party commissar at the factory and guards his power jealously, not only to appease the system, but because there is a secret tunnel underneath the Iron Curtain that begins with the “dungeon door” in his basement office. Dieter suffers from greed and the fact that he renounced true love for the little power he has. The tunnel was being used only to smuggle fine food ingredients so he could craft wonderful recipes for an Italian restaurant in the West owned by his forlorn lover, Markus. But now they are controlled by a mysterious Russian KGB Agent using them to smuggle Soviet gold bars out, and blood diamonds into East Germany
Bilingual Comprehension of Accented Speech and Spoken Code Switches
No full textAcross three experiments, the current study explored how accented speech and coarticulation impact how bilingual listeners comprehend code-switches in speech. Eye-tracking methodology was used to compare responses to single-language and code-switched sentences. Experiment 1 observed how accented speech influenced the costs involved in comprehending code-switches by comparing responses to speakers that had North American English accents to speakers with Juarez/El Paso Spanish accents when speaking English. Experiment 2 compared responses to English speech produced by speakers with North American English, Flemish, and Bulgarian accented speakers. To examine coarticulation as a cue to an upcoming code-switch, Experiment 3 compared naturally produced speech to speech that manipulated coarticulation prior to a code-switch. Results demonstrated that switch costs are involved in the comprehension of code-switches, non-English accents impact a listeners’ comprehension of English speech, and the relative impacts of accent on switch costs vary across accent types. Additionally, the subtle cue of coarticulation assists listeners when comprehending code-switches. These findings suggest that bilinguals may use accent as a cue to anticipate upcoming speech. However, when a cue is deemed unreliable based on a bilingual’s previous experiences, the listener then uses sub-lexical cues such as coarticulation to facilitate the comprehension of code-switches
Confronting Borders, Creating Community: Transregional Consequences of Migration and Detention Between Guatemala and Iowa, 1980-2018
No full textThis dissertation explores themes of borderlands, migration, detention, and community. It uses the 2008 ICE raid on Agriprocessors, a kosher meatpacking plant, in Postville, Iowa as a case study to look at Transregional migration from Guatemala to Iowa. As migrants settled in Postville, they added to the changing demographics of Postville, and the community grappled with becoming a multicultural space. The ICE raid was a shock to the residents of Postville and the towns in Guatemala. In the aftermath of the raid, many workers faced arrest and deportation. Community solidarity emerged in both Guatemala and Iowa as a counter to state violence and intervention
Examining The Effects Of A Week-Long Social Media Abstinence Intervention, Iweek, On General Well-Being, Mental Health, And Body Image Concerns In Latina College Students
Get PDFLatina college students, on average, spend approximately 30 hours per week on social media, highlighting the pervasive influence of social media on their lives. While social media can facilitate interpersonal relationships, its impact on mental and physical health is evident in the literature. Problematic social media use has been associated with increased rates of depression, anxiety, and decreased life satisfaction. Additionally, exposure to idealized images on social media platforms often leads to lower body satisfaction, particularly among women. Social media may also influence eating behaviors through the abundance of food advertisements and contribute to sedentary behavior, as individuals spend significant amounts of time on their phones rather than engaging in physical activity. While taking a break from social media has shown promise in improving mental health outcomes, its effects on other aspects of health remain uncertain. Thus, the present study assessed the effects of a social media break intervention grounded in Self-Determination Theory (SDT) on various health outcomes, including depression, anxiety, stress, well-being, body image, healthy eating, physical activity, and sleep. Additionally, the study explored whether the intervention influenced participants’ basic psychological needs related to autonomy competence, and relatedness. Latina college students (N = 221; M_age= 19.84) completed a demographic questionnaire, objective and subjective measures of weekly social media use, the Depression, Anxiety, and Stress scale, the Short Warwick-Edinburgh Mental Well-Being scale, the Body Image States scale, the Healthy Eating Scale – 5, the International Physical Activity Questionnaire – Short Form, the Insomnia Severity Index, the Treatment Self-Regulation Questionnaire – Autonomy subscale, the Perceived Competence Scale, the Basic Psychological Needs scale – relatedness subscale, and an evaluation survey online before being randomized into the intervention or control group. The intervention group abstained from social media for a week, while the control group continued using social media as usual. A total of eight 2 (pre, post) X 2 (iWeek, control) mixed ANOVAs assessed changes in pre- and post-intervention scores on each outcome variable for iWeek compared to the control condition. Results indicated improvements in depression, anxiety, stress, and body image satisfaction among the intervention group. However, no significant effects were observed for well-being, healthy eating, or physical activity. Interestingly, sleep showed improvement favoring the intervention condition. There were no changes in autonomy, competence, or relatedness scores. Overall, the study replicates previous findings regarding the positive effects of a social media break on mental health outcomes. The observed effects on body image satisfaction and sleep are nuanced and warrant further investigation to elucidate the mechanisms underlying these improvements. By shedding light on the potential benefits of social media breaks for various aspects of health, this study contributes to a deeper understanding of how Latina college students can manage their social media use to promote overall well-being
Atlas-Based Analysis Of The Neural Projections From The Lateral Hypothalamic Area To The Lower Brainstem In The Adult Male Rat
Get PDFWithin the last decade, the number of diseases associated with dysregulation of the neural circuits responsible for energy balance, glucosensing, and feeding control has increased. One brain region containing these circuits is the lateral hypothalamic area (LHA), which plays an important role in the sleep/wake cycle, energy balance, and motivated behavior. Although the LHA has been termed a â??feeding centerâ??, other regions within the hindbrain are known for the regulation of similar functions including energy balance, glucosensing, and feeding control. While many studies have explored and reported projections from the LHA to the hindbrain, few have further investigated the interconnections between neighboring cytoarchitectonically defined LHA subdivisions. To address this gap in our understanding, we have surveyed three distinct regions within the LHA, as characterized in the standardized atlas, Brain Maps 4.0 (BM4.0). We injected a cocktail consisting of the retrograde tracer, cholera toxin subunit B (CTb), and the anterograde tracer, Phaseolus vulgaris leucoagglutinin (PHA-L), in three adult male Sprague-Dawley rats to visualize their LHA interconnections with the hindbrain. We mapped the traced interconnections to hindbrain atlas levels 52â??73. Of the three cases, subject 19-054 displayed unique connectional patterns for various HB subregions. Through various IHC preparations, we observed sources of LHAd inputs in the form of CTb-ir perikarya, and LHAd outputs in the form of PHA-L-ir axons in reticular nuclei and regions within the dorsal vagal complex (DVC). Hence, bidirectional communication, as evident from both retrograde and anterograde labeling, exists for the proposed LHAdâ??HB neural circuits. We also phenotyped some of the neuronal populations in the hindbrain overlapping with these regions. Overall, this provides evidence for the existence of bidirectional structural connectivity for the LHAdâ??DVC neural circuit, and provides a foundation for its further elucidation. Obtaining accurate standardized maps in addition to molecular information of this neural circuit in relation to the regulation of gastrointestinal function and feeding behavior will be critical for generating effective therapies. The further delineation of this neural circuit may also prove critical for the development of novel therapeutic strategies aimed for the treatment of diabetic patients. Furthermore, by confirming LHAd connections to the hindbrain DVC, we can create and test hypotheses about how these connections work, supplemented by standardized maps of the entire network that may be utilized for large-scale projects such as deep brain stimulation, optogenetics, and even the use of light-sheet microscopy to produce a 3-D map of this important neural circuit
Academic and Ethnic Identity’s Moderating Effects on Intergenerational Conflict, Academic Motivation and Alcohol Outcomes Relationship Within First-Year Hispanic College Students’
No full textWhile alcohol use is a public health concern for all college students, first-year college students are at higher risk for drinking and experiencing alcohol consequences. The increased risk may be attributed to the stress of transitioning from high school to college. For many of these students, this is their first-time gaining independence and trying to find out how they fit into society. Family conflict commonly occurs when students start college because they develop their values and beliefs, especially Hispanic college students. Intergenerational conflict (IGC) is a subtype of parent-child conflict that arises when the child deviates from traditional Hispanic values, attitudes, and beliefs. Little research examines how IGC, specifically conflict within domains of family expectations (FE), education and career (EC), and dating and marriage (DM), affects alcohol use and academic motivation among first-year college students. Despite this knowledge gap, studies have shown that Hispanic college students who experience IGC are likely to have more alcohol-related problems and consume more alcohol. Further, limited research has examined potential protective factors that could buffer the adverse effects associated with IGC. Ethnic identity has been found to decrease drinking and family conflict and increase academic achievement among Hispanic college students. Additionally, academic identity fosters motivation for academic achievement among college students. The current study is among the first to examine IGC and academic identity among first-year Hispanic college students. Further, the study is among the first to investigate if academic identity could be a protective factor regarding IGC. This study aims to explore the influence of identity, including ethnic and academic identity (e.g., achieved, moratorium, foreclosed, and diffused) on the relationship of intergenerational conflict (e.g., family expectations, education/career, and dating/marriage) to academic motivation (e.g., amotivation, intrinsic, and extrinsic motivation) and alcohol (e.g., use and consequences). Participants (n=268, 78.2% female) completed a two-timepoint survey to assess intergenerational conflict, alcohol use, consequences, academic motivation, and ethnic and academic identity. Five path analysis models were used to investigate the relationships between our time point 1 predictor variables, IGC (i.e., FE, EC, and DM) and identity, as well as our time point two outcome variables, alcohol outcomes, and academic motivation. Results indicated that IGC-DM had a direct effect on alcohol use. Moreover, results suggest that when ethnic and academic identities were introduced, all aspects of IGC had relationships with alcohol use or consequences. In contrast, IGC had no direct effect on the three aspects of academic motivation (i.e., motivation, intrinsic, and extrinsic motivation). Like our alcohol outcome, academic identity had a moderating effect on motivation and intrinsic motivation. Our results show that identity and IGC are complex and that different combinations can be protective or risky toward alcohol outcomes and academic motivation. Future research should focus on developing culturally informed interventions to support Hispanic college students and other ethnic minority students navigating and balancing culture and academics