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The Effect of Serotonin on Males’ Neural and Behavioral Mechanisms to Female Ultrasonic Vocalizations and Urine in the House Mouse \u3cem\u3e(Mus musculus)\u3c/em\u3e
Get PDFAnimals communicate with multimodal signals (e.g., a mix of auditory, visual, or olfactory information) spanning several modalities; these signals may provide receivers with more complete information to allow for more accurate behavioral decisions. Past research suggests that serotonin plays a role in encoding multimodal social information (e.g., social partner presence) during communication events. Nevertheless, to our knowledge, no experiments have explicitly tested this hypothesis. 5-HTP, a precursor for serotonin, has been shown to increase serotonin in a region of the auditory midbrain, and is affected by social context. In our experiment, we asked the question: Does an increase in 5-HTP affect the behavior and neural activity of mice (Mus musculus) when exposed to multimodal stimuli? Mice are known to use multimodal signals (vocalizations and olfactory signals) during communication and are therefore appropriate models for this experiment.To answer this question, we presented olfactory (female urine) and auditory (e.g. female ultrasonic vocalizations, USVs) stimuli to male mice. Prior to the behavioral experiment, mice were either given 5-HTP or saline. We then quantified the behaviors that occurred when male house mice were presented with either female USVs or both female urine and USVs together. We investigated sexual activity (e.g., grooming), anxious activity (e.g., digging), general activities (e.g., rearing and jumping), and investigative behavior. After exposure, neural activation was quantified via immunohistochemistry of the auditory midbrain. We predict that mice given 5-HTP and exposed to multimodal stimuli will have a higher degree of neural activation. The findings of this study will allow us to better understand the relationship between multimodal signal processing, serotonergic activity, and behavior
Disability in Disney
Get PDFRené Girard’s mimetic theory emphasizes the importance of imitation in shaping all human behavior, including desire. The questions driving this project were founded with human imitative behaviors in mind: Is Disney creating characters with disabilities that are inherently desirable to imitate (attractive, popular etc.)? Is Disney creating complex, dynamic characters with disabilities? Unfortunately, the answer is no. Within the Disney canon of animated films there are 13 characters identified as having physical disabilities. By tracking the language used to refer to these characters and their foils an alarming pattern was revealed. When formal titles, the character’s name, and nicknames were removed, the remaining terminology was assessed using Wordcloud technology to visually represent the frequency with which different terms were used in reference to each character. While only three of 13 characters with disabilities are characterized as villains, all of the characters with disabilities are most commonly referred to using derogatory or infantilizing terminology. On the whole, good or evil plays little role in the language referring to characters. Instead, those characters with disabilities had a high frequency of being referred to as “monster,” “little,” or by their disability, a trend most noticeable in Disney’s adaptation of Victor Hugo’s Quasimodo. Children ages three to twelve who are the target audiences of these films are most vulnerable to absorbing Disney’s discrimination against disabilities. The characters with disabilities act as mimetic mediators between developing children and people with disabilities as children will retain and regurgitate the language and treatment they witness toward disabled characters. This negative mimesis is further perpetuated by the cute culture of Disney and their ostracization of characters that do not fit the ideal attractive standard. The villainization of a disabled body in Disney feeds into the scapegoating of people with disabilities and is harmful in maintaining societal stereotypes
Peer Relationships, Social Media Use, and Sport Commitment
Get PDFExtant work suggests peers play a vital role in shaping athletes’ positive and negative sporting experiences. Recent descriptive work has explored the importance of peers in sport by examining friendship quality and relevant motivation constructs (Weiss & Smith, 2002). Although evidence suggests quality sport friendship can foster sport participation, limited work has examined social interactions through social media. The primary purpose of this study was to provide a descriptive account of social media use and satisfaction among youth sport athletes. A secondary purpose was to examine social media use and satisfaction as predictors of sport friendship quality dimensions (positive friendship quality and friendship conflict). Youth athletes (N = 163; Mage = 15.51 years; 73.6% male) provided demographic information, completed an established measure of friendship quality, and reported on frequency and satisfaction of social media use. Descriptive data suggest Texting, Instagram, and Snapchat were the top used mediums for communication. Positive friendship quality shared a positive association with Texting and Snapchat use. Friendship conflict shared a positive relationship with Instagram and Snapchat use. No social media medium shared a significant relationship with social media satisfaction. Multivariate multiple regression analysis showed greater use and satisfaction of Texting, Instagram and Snapchat to predict stronger friendship quality dimensions. This study helps add to the existing literature base by showing how social interactions that take place outside of the typical sport setting may play a role in shaping athletes sporting experiences
Artist Talk & Reception with Sandra Hansen
Get PDFA poster for an artist talk and reception on September 30, 2022, related to the exhibition No Planet B. The exhibition was held September 2–December 10, 2022.https://digitalcommons.hope.edu/kam_poster/1059/thumbnail.jp
Analysis of United States National Security Policy on Cyberterrorism from China
Get PDFCyberterrorism is a relatively new threat globally but has increased rapidly in recent years due to the development of more sophisticated and advanced computer-based technology. Many people question the existence of a substantial threat from the Chinese government in terms of their use of cyber technology on the United States. Intelligence shows China has continuously used their cyber technology capabilities as a way to exploit other countries, businesses, and local populations. Scholarly research, news outlets, and official government documents all conclude that Chinese cyberterrorism is a large security threat to the United States. China has used their technology to infiltrate U.S. networks and infrastructure in the past. They are a continued threat, with government agencies constantly watching and assessing threat levels of Chinese technology along with the political and economic atmospheres. This research examines the implications of how increased cyber attacks from China could be catastrophic to U.S. infrastructure, economy, and intelligence. Along with how the United States has combated previous attacks, developed new technology and implemented regulatory policy to protect infrastructure
Connecting Chemical Composition and Methane Production in a West Michigan Peatland
Get PDFThe future net radiative forcing of peatlands will depend in large part on changes in methane emissions. However, current climate models lack a mechanistic representation of methane production. We conducted an anaerobic incubation experiment using peat from various depths in five cores collected from a West Michigan peatland in order to connect methane production to observable differences in the chemical composition of peat and peat pore water. We hypothesized that less decomposed peat may have a larger supply of fermentable sugars that can thus produce more methane than more decomposed peat. C:N, hydrolyzable amino acids, and neutral sugars were analyzed to evaluate the “quality” of the peat. Our results indicated that surface peat produces more methane and carbon dioxide than samples taken from greater depths. Surface peat had higher yields of arabinose and xylose, indicating higher availability of relatively labile hemicelluloses compared to deeper peat. This coincided with a higher amino acid yield in comparison to total nitrogen and a higher C:N, indicating less extensive decomposition in these samples. This is consistent with our hypothesis that methane production potential is correlated with peat quality. These results suggest that analysis of the chemical composition of peat can be used to assess methane production potential and predict the future radiative forming of peatlands
Changes in Chromatic Contrast of Avian Plumage in Forests with Different Levels of Deer Browsing
Get PDFVisual signal propagation through the environment can be influenced by many factors, including the visual background. For example, normally camouflaged animals can appear quite salient when the environmental substrate is changed. Deer can alter this visual background by consuming the forest understory; ultimately this can have implications for species that use visual signals to attract a mate or defend a territory. We are interested in studying how deer browsing affects the chromatic contrast (i.e., how much an animal stands out from the background for a given receiver) using an avian model system. Brown headed cowbirds (Molothrus ater) and wild turkeys (Meleagris gallopavo) inhabitat the forest understory that is subject to deer browsing . We used published data on cone photoreceptor sensitivity of these species to model chromatic contrast of avian plumage against forest backgrounds. We also used a general avian eye model to investigate the chromatic contrast of plumage colors across the visible light spectrum, from the red of Northern cardinals (Cardinalis cardinalis) to the blue of blue jays (Cyanocitta cristata). To calculate chromatic contrast we used spectroscopy measurements from (1) the forest understory as the visual background, (2) plumage reflectance and (3) irradiance measures. We modeled this in both deciduous and mixed forest types and at different heights from the forest floor (i.e., low and high). We predicted that areas that allow deer will cause birds to be more conspicuous. Additionally, we expected the effects of deer browsing to be greater at lower heights because of the increased foraging and disturbance of the forest floor. In the future, we will examine if achromatic contrast (i.e., contrast based on brightness cues) are affected similarly. Taken together, this work will shed light on how different environments can drastically affect the way birds communicate
Exploring Halide Perovskite Structural Tunability to Design Materials for Dynamic Photovoltaic Windows
Get PDFHalide perovskites offer exciting potential as photovoltaic materials and simply as semiconductors. Specifically, their structural tunability has become of greater interest as researchers begin to search for novel ways to tune the materials to achieve improved solar cell stability or to target new applications. One potential technology which halide perovskites could enable is dynamically switchable photovoltaic windows: windows which can transition between photovoltaically active (dark) and non-photovoltaic (transparent). We build toward this goal in this work by investigating the intercalation and deintercalation of methylamine gas into 2-dimensional Ruddlesden-Popper (R-P) phase halide perovskites of the type A2PbI4. As has been shown with 3D methylammonium lead iodide films, the intercalation of methylamine into the halide perovskite lattice results in a color change to a clear crystalline phase. We find that in some 2-D perovskite systems, deintercalation of the methylamine gas is incomplete, resulting in the formation of secondary phases including n=2 R-P and 3D perovskites, as well as lower dimensional materials; however, other 2-D perovskite phases show reversible intercalation/deintercalation with methylamine, indicating stronger binding between the long-chain ligand and the lead halide octahedra of the 2-D perovskite sheet. This work reveals the relative affinity of various R-NH3+ molecules, specifically R-C8H9-NH3+ materials such as 4-hydroxy phenethyl ammonium, for the halide perovskite lattice and indicates that templating the 3-D CH3NH3PbI3 structure with carefully selected long-chain cations could lead to better reversibility in dynamic photovoltaic windows. Work continues to develop improved guidelines for the design of 2D/3D halide perovskite materials for an array of applications
Automatic Alignment of Remote Imagery for Use in Sand Dune Modeling
Get PDFThe Hope College Dune Group has been studying West Michigan sand dunes for over twenty years. The group’s interests include observing the mechanisms and effects of sand transport, as well as learning how sand movement and resident dune vegetation affect one another. One of the fundamental tasks of this group is to use machine learning algorithms to create accurate ground-surface and vegetation models from drone imagery in an automated way. A key step in this process is the identification of various types of surface coverage–such as sand, live grass, trees, and other vegetation–automatically from images. An eventual goal of this work is automatic land cover classification at the complex-wide scale.
The scale of the images ranges from high-resolution photos taken with digital cameras to orthomosaics of entire dune complexes taken remotely from a height of around 120 meters. This gives rise to the need for automated alignment and accurate coregistration of multiple images. One technique for image alignment involves using artificial neural networks to identify key points in two or more images and match sets of key points between images. In this poster, we will report on our work on land type classification using a variety of image classification techniques. We produce detailed classifications of high-resolution, low altitude images and use this as a template for creating similar classifications from high-altitude, lower-resolution imagery. We also report on early attempts to align images from multiple perspectives and sources. If automatic image alignment is successful, multiple images can be used together in network training and prediction, and some field-based data collection workflows can be streamlined
Mental Health and Homelessness
Get PDFSince the onset of the COVID-19 pandemic, one area tragically impacted has been access to secure housing. The huge economic impacts of the shutdowns and job losses of the pandemic prompted the federal as well as state governments to provide emergency resources for help keep people housed as well as to help those without housing to secure a place to live. These interventions have had many important impacts. They have not, however, reduced or ended the rising levels of homelessness nationally since 2016. The result is an increasingly visible epidemic of unsheltered homelessness, affecting both individuals and families. When analyzing factors influencing those who are experiencing housing insecurities, individual factors, as well as systemic factors, are contributing to the ongoing issue. In regards to individual factors, mental health continues to influence homelessness, becoming a crucial factor with the deinstitutionalization in the 1960s and 1970s. This study proposes to examine the impact of mental health as a crucial factor among many that predicts and results from experiences of homelessness, exploring potential solutions to prevent mental health, in the context of other factors, from leading to homelessness in the ways currently occurring