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Selective Preservation of Structural Carbohydrates During Peat Formation
Get PDFThe structural carbohydrate sphagnan has been hypothesized to play a role in slowing the degradation of Sphagnum moss, and therefore contribute to carbon sequestration in peatlands. Sphagnan is composed of a galacturonic acid and rhamnose backbone. However, it is currently unclear whether sphagnan persists beyond early-litter degradation and plays a role in the long-term preservation of organic matter in peatlands. In this study, we analyzed hydrolyzable neutral sugars, using rhamnose as a proxy for sphagnan content, and tracked the concentration of rhamnose present within moss before and after a 270-day period of decomposition, as well as the concentration of rhamnose at different depths within five peat cores collected from a southwest Michigan bog. While there was a clear increase in the relative abundance of rhamnose during the moss decomposition process, there was little change in the rhamnose concentrations within the peat cores in relation to depth. This implies that the degradation of sphagnan occurs at roughly the same rate as other sugars. However, an increase in the concentration of glucose with depth, with decreasing abundances of xylose and arabinose, indicates that cellulose is selectively preserved compared to hemicelluloses, accumulating over degradation. Overall, our results show that sphagnan is selectively preserved during litter decomposition, but other structural carbohydrates may play a larger role in the long-term preservation of organic matter in peatlands
Effect of Post-Warm-Up Transition Time on Anaerobic Performance in Female Collegiate Volleyball Players
Get PDFPost-warm-up transition time (PWTT) is the period of time between the end of a pre-game warm-up and the beginning of gameplay at a particular sporting event. During this period of time, typical pregame traditions are completed such as the playing of the National Anthem and recognition of players and coaches. This length of time can vary from sport to sport. Research shows that a dynamic warmup is encouraged to improve performance and decrease the risk of injury. Further, rest periods are necessary for optimal performance. Too short of a recovery time can result in muscle tissue damage, but too long of a recovery time can nullify the effects of the warm-up. Little research exists to determine the optimal PWTT that results in peak anaerobic performance. Therefore, the purpose of this study was to identify the PWTT that resulted in optimal performance on a series of anaerobic fitness tests among female collegiate volleyball players. Biologically female Hope College volleyball players will participate in three testing sessions in which they will complete a standard dynamic volleyball warm-up followed by one of three randomized conditions: a 5-minute, 12-minute, or 20-minute recovery period. Following their recovery time, participants will then complete a vertical jump test, agility T-Test, and 20 m sprint test. Maximum heart rate will be monitored and recorded throughout each testing session, along with perceived intensity following the completion of each test. It is hypothesized that the 5 minute condition will yield the best performance results among participants, while the 20-minute condition will yield the worst. Significant results would encourage the revision of pregame traditions in order to optimize PWTTs in an effort to maximize anaerobic performance during volleyball gameplay. This study is ongoing and the results will be available during the research celebration
Culturally Responsive Teaching and Religious Diversity
Get PDFWith the ever-increasing classroom diversity, developing competency in culturally responsive teaching is critical to successful teacher preparation. Culturally responsive teaching values diverse students\u27 cultures and utilizes them to maximize instructional effects for each student. Keeping in mind that Hope College is a Christian Institution, there may be some religious biases and unique challenges compared to a public university. Religion is a less discussed topic in diversity-related courses, so our research aims to investigate the influence of religious diversity in teaching. For our study, we administered a survey to eight classes at Hope College in varying grades (i.e., Freshman vs. Seniors) and major disciplines (Education majors vs. non-Education majors). The survey asked students to classify words that imply different religious beliefs and briefly explain their choice. We predict that people with low prior knowledge about the world\u27s various religions will agree more on these stigmas because they base their opinion on common stereotypes rather than facts. Consequently, higher exposure to cultural diversity in education will result in students forming more informed views on religions and their stereotypes, developing individuals into more effective, culturally responsive teachers
Infant Object Transference and Play Preference
Get PDFThis study investigates the link between virtual object learning and physical object play. This concept is relevant for today\u27s digital culture where infants are routinely exposed to online educational programs (Barr, 2010). Research is unclear, however, about if and how what infants learn about objects on screen (visual preferences) applies to play choices — primary contexts for early learning.
The ability to recognize that an object\u27s image on a screen is the same as the physical object is referred to as object transference (OT). For example, OT would be the ability to see an image of a cow on a screen and recognize that cow in real life. Prior studies demonstrate that infants at least 15 months old possess OT (Soska, 2010; Barr, 2010) with some studies suggesting that OT could occur as young as 6-9 months (Jowkar-Baniani, 2011; Rose, 1977).
In this ongoing study, infants participate in two tasks. First, infants watch for six minutes as 12 objects appear on screen in sets of three for 3.5 seconds at a time (Figure 1A-B) while researchers record how long infants look at each object through eye tracking. Second, infants are given 6 minutes to play with the 12 physical objects off-screen (Figure 1C) while researchers record how long they play with each object.
Preliminary data from 5 infants aged 8-21 months indicates a weak, positive correlation between visual and play preferences (mean r=.10; Figure 1D), however a larger sample size is needed before any conclusive results can be drawn. Future research will clarify conflicting studies on when OT develops and how infant age influences visual and play preferences. Enhancing knowledge about the correlation between infant visual preferences and play preferences can provide insight into the effectiveness of infant virtual education
A Christian Framework for Competitive Sport
Get PDFChristianity and competitive sport have a long history of interaction, oftentimes adversarial in nature. Yet in the last century and a half, Christians have embraced sport in such foundational ways that it is often now hard to imagine sport without certain Christian ideas and images. Competitive sport has taken on many forms and has been used in many ways both destructive and constructive. This wide range of Christian responses to sport throughout history begs the question: Does competitive sport truly fit within a framework of Christian ethics and values?
In order to answer this question, I will engage with theories from a variety of scholars from philosophy, kinesiology, sport studies, and religious studies who have taken different angles — sometimes antithetical — to offer their own answers to this question. Some answer with a simple no , others a more complex no , and many others a reluctant or sometimes resounding yes . Hidden in this question are a few other questions that will illuminate how I approach this larger question: How do we define competition in sport? Is competition amenable to virtue development? Do the positives of sport outweigh the negatives?
Once these questions are answered, the ultimate goal of this project is to answer the simple and yet infinitely complex question of, How? How does a Christian engage in sport in healthy ways, edifying ways? There are some theories which encourage healthy engagement in sport, and I will explore some of them in order to provide a roadmap for Christians in the world of competitive sport
Temperature Sensitivity of Nitrogen Mineralization in Peat From a Southwestern Michigan Bog
Get PDFIn this study, we measured inorganic nitrogen (nitrate and ammonium) released from peat cores from Miner Lake bog at two temperatures to analyze the impact of climate warming on the peatland nitrogen cycle. We hypothesized a higher nitrogen release in samples incubated at warmer temperatures. Furthermore, previous research indicates shallow peat decomposes faster than deeper peat. Therefore, we hypothesized faster nitrogen mineralization in shallow samples. We collected peat cores from two locations from Miner Lake Bog in Allegan County, Michigan: a plot in the center of the bog and a sedge meadow site near the edge. Two samples for each depth (0-0.5 meter, 1.5-2 meters) were taken at both sites and homogenized. Microlysimeters, consisting of two-chambered filter towers, were acid washed and 20 g of acid washed sand was added to each upper chamber. 50 g of peat was added onto the sand and was left to equilibrate for four days. Microlysimeters were leached with 80 mL of 0.01M CaCl2 solution and the concentration of nitrate and ammonium in the leachate were quantified using ion chromatography. Microlysimeters were incubated for two weeks before leaching procedures were repeated. A separate field-based cation-anion exchange analysis was performed through the installation of plant root simulators. In both the lab and field experiments, we consistently found that cumulative mineralization was higher at the warmer temperature, indicating that warming will increase the rate of nitrogen cycling in peatlands. We also found that at a lesser extent mineralization was higher in surface peat than in more degraded deep peat layers
Dia de los Muertos
Get PDFA poster advertising a Dia de los Muertos ofrenda hosted by the Kruizenga Art Museum and Latin Americans United for Progress (LAUP) from October 31-November 4, 2023.https://digitalcommons.hope.edu/kam_poster/1058/thumbnail.jp
Re-Indigenization of Song, Chant, and Dance in the Pacific
Get PDFMusic plays a vital role in the functioning of culture and society, especially for non-literate cultures in the Pacific. Research shows that there were many different traditions of song, chant, and dance throughout Melanesia, Micronesia, and Polynesia before Europeans colonized the islands. This colonization led to a shift in traditional music and life partly because of acculturation and partly because of church censorship. Now, indigenous Islanders are reclaiming parts of their lost identity through traditional language and music, calling for policy change in their contemporary forms of music, and passing on their knowledge by educating the next generation
Creation of an N-terminal xCT Mutant Lacking Lysines for Use in Protein Turnover Studies
Get PDFxCT plays a role in protecting cells from oxidative stress as well as intracellular glutathione synthesis. If this process is impeded, reactive oxygen species accumulate in the cell, leading to cellular damage, and if left unchecked, it can lead to neuronal loss. Ubiquitin is a small protein that some evidence suggests can negatively affect the stress response pathway modulated by xCT, as well as induce cell death. It is hypothesized that ubiquitin binds to xCT on the N-terminal lysine residues, and there are six conserved lysines in the N-terminal domain at positions K4R, K12R, K30R, K37R, K41R, and K43R. Previous work in the Chase lab has shown that the replacement of individual lysines with arginines does not result in a change in the ubiquitination of a transporter. Therefore, the goal of this project is to create a mutant of xCT in which all of the lysines in the N-terminus are replaced with arginines in order to determine if that will lead to a loss of ubiquitination of xCT and an overall change in the activity and regulation of the transporter. To do this, we did a successive site-directed mutagenesis approach to ultimately produce a mutant with all lysines replaced with arginines. Currently, we have created a construct that has mutations at K4R, K37R, K41R, and K43R, and we are attempting to add the final mutations. Once this is accomplished we will express it in COS7 cells, and determine if the mutant can still be ubiquitinated
Dopaminergic Synapse Loss in 6-OHDA Lesioned Zebrafish
Get PDFParkinson\u27s disease is a neurodegenerative disorder caused by degeneration of dopaminergic neurons, and an early symptom of Parkinson\u27s disease is olfactory dysfunction. A common animal model used in Parkinson\u27s disease research is zebrafish because of their unique neuro-regenerative ability, which is particularly in their olfactory bulb. In order to create a model of the early stages of Parkinson\u27s disease we injected zebrafish with the neurotoxin 6-hydroxydopamine (6-OHDA) to induce the degeneration of dopaminergic neurons in the olfactory bulb. Olfactory system recovery post 6-OHDA injection has been recorded in previous literature, but the state of synaptic dopaminergic synapses post-injection has not yet been investigated. In this study, we explore the effects of 6OH-DA lesions on dopaminergic neuron number and synaptic density within the olfactory bulbs of control and experimental samples at 1- and 3-days post 6-OHDA injection. For this, we harvested zebrafish brains post-injection and performed immunohistochemical staining on the neural tissue. We used primary antibodies against SV2 (synaptic vesicle 2) and TH (tyrosine hydroxylase) that allowed us to observe pre-synaptic terminals of dopaminergic neurons, respectively, as well as their overlap. We observed the tissue using confocal microscopy, measured the optical density of the signal, and counted the number of dopaminergic neurons present within each tissue sample. So far, we have qualitatively observed differences in the location of the synaptic vesicles and olfactory glomeruli (i.e., sites of synaptic connections) between treatment groups. Our research is the first to examine dopaminergic synapse loss resulting from treatment with 6-OHDA, and may give insight into preventative treatments of neurodegenerative disorders like Parkinson\u27s disease in the future