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COMPARATIVE BIOMECHANICAL ANALYSIS OF A FEMALE HAMMER THROW ATHLETE FOR BACK-TO-BACK AMERICAN RECORD YEARS
Get PDFHammer athletes must optimize performance variables to maximize their official distance. Analysis of key performance variables might explain how the subject improved an American record year in 2018 to another record in 2019. A 3-D analysis was performed on trial videos from 2018 and 2019. Release height, release velocity, release angle, and hip-shoulder separation were compared among years and throws, and their relationship with official distance was assessed. Release height (p \u3c 0.01) and release angle (p \u3c 0.01) were more consistent in 2019 than 2018. The relationships among official distance, release height (p = 0.06), and hip-shoulder separation (p = 0.04) were different between years. The efficient use of hip-shoulder separation could be responsible for the increase in official distance between years
Hormone-Induced Decidualization of Human Endometrial Stromal Cells
No full textHuman endometrial stromal cells (HESCs) are difficult to study in vitro due to their short window of viability outside of the human body. A previously developed, stable, immortalized HESC cell line retains reproductive hormone responsiveness to in vitro decidualization assays (Krikun et al 2004). Our laboratory aims to demonstrate that the same HESC cell line responds to estradiol and progesterone as described in the Krikun et al. paper. We hypothesize the HESCs will respond normally to reproductive hormones estradiol and progesterone. Treatment with both estradiol and progesterone, at the appropriate concentrations, will initiate decidualization in HESC cultures. HESC cultures will be treated with estradiol and progesterone individually or in combination for eight days to induce hormone-dependent gene expression changes. We will collect total mRNA and generate cDNA for quantitative, real-time polymerase chain reactions (qrtPCR). This data will allow measurement of the changes in gene expression following hormone treatments. If the cells respond normally to hormones, we expect to measure increases in expression of target genes IGFBP-1, PAI-1, and TF compared to the housekeeping gene β-Actin. We expect hormone-induced decidualization of the HESCs will increase expression of CD147 (Basigin) as demonstrated in mice (Chen et al. 2009). The data will lay a foundation for future experiments to determine the necessity of CD147 in the decidualization process. We will also include the results of this study in a developing manuscript from Dr. Belton’s laboratory which we anticipate publishing in late 2021
Comparison of Activity Patterns for American Beavers, Gray Wolves, and Muskrats
No full textAmerican beavers (Castor canadensis) share the same niche as muskrats (Ondatra zibethicus) by creating lodges and they compete with one another when their vegetation needs overlap. Beavers face predation from gray wolves (Canis lupus). The prediction is that beavers adjust their activity pattern in order to reduce competition with muskrats and to avoid predation from gray wolves. Activity patterns were found by using the Snapshot USA database. Beavers share the same nocturnal activity pattern with muskrats and gray wolves have cathemeral patterns that most likely adjust to the available prey\u27s schedule. This research has revealed that beavers have a definitive schedule that is not heavily affected by competition or predation, but more research may need to be done where an overlap of beavers with muskrats or gray wolves is more well known
Characterization of LAMP Primer Design Compared to Published Results
No full textThe current worldwide pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) produces an urgency to find a way to quickly test people for the virus. Currently a Real Time Polymerase Chain Reaction (RT-PCR) assay is the “gold standard” test to identify infected individuals. Therefore, I am seeking to use Loop Mediated Isothermal Amplification (LAMP) as an assay to detect SARS-CoV-2. LAMP offers greater specificity and sensitivity compared to PCR. The overall objective will compare and characterize Dr. Jennings’ designed LAMP primers with published primer sets with confirmation of successful LAMP amplification via RT-PCR and gel electrophoresis. Using the products of LAMP, a RT-PCR shall confirm that SARS-CoV-2 amplification occurs reproducibly. Confirmation relies on a restriction enzyme digest to see whether the RT-PCR and LAMP reactions produced SARS-CoV-2 RNA. This project will help confirm that the Primers Dr. Jennings designed will detect SARS-CoV-2 RNA
Making a New American Identity: The Associated Press and Nazi, 1933-1938 Germany
Get PDFProposal: My paper, “Making a New American Identity: The Associated Press and Nazi Germany, 1933-1938”, was originally submitted as my final project for Dr. Nick Dupras’s History 390 class. HS390 focuses mainly on teaching methods of historical research and source analysis, and the entire semester is spent developing a research question, locating primary and secondary sources, and synthesizing the research into a long scholarly essay. As such, the NMU library and archives are the first points of call for any student taking the class. The archives are particularly important, as they are the most comprehensive repository of primary documents on campus.
With a few small exceptions, all of the resources I used for this paper came from the Olson Library or from the archives. My most significant challenge was creating a research question that reconciled the topic I wanted to write about – American public opinion about the antisemitic policies of Nazi Germany – with the primary documents available in the archives, which mainly cover local UP history. Early in the semester, I met with Marcus Robyns, the university archivist, to discuss my options. He suggested that I use the large microfilm collection in the archives to look at how various UP newspapers covered the events of the Holocaust as they were occurring. I quickly ran into a problem, however; when I began going through editions of the Mining Journal from 1933, I realized that most of the front-page articles about Nazi Germany came from the Associated Press (AP), rather than local journalists. While the articles were interesting, they only offered me information on how the AP covered Nazi Germany, and did not give me a picture of how that coverage was received by the people of Marquette.
Use of the library resources helped me turn this problem into the linchpin of my essay. I used the library’s OneSearch tool to look up articles on American press coverage of the Third Reich, and I found multiple secondary sources that examined the AP’s dealings with the Hitler regime. Several articles from German historians, published after 2016, suggested that the AP’s Berlin bureau willingly censored its own articles to avoid offending the German Propaganda Ministry. These articles created enough of a stir that the AP published a 150-page internal report in 2017, attempting to justify its soft coverage of Nazi Germany. The discovery of these sources enabled me to return to the archives and examine the Mining Journal microfilms with a new perspective. With the knowledge that the AP’s relationship with Nazi propaganda was closer than I had previously believed, I was able to compare the front-page articles with editorial columns in the paper’s back pages, written by local journalists. My question centered around the assumption that for most Americans, especially those in small towns like Marquette, the AP was the only regular source of information on Nazi Germany. Knowing that the AP’s coverage of the Nazis was not objective, I sought to analyze the impact of their bias on local perceptions of Nazi antisemitism and military aggression.
Throughout the semester, I spent at least two hours per week in the archives going through microfilms. I read hundreds of articles published between 1933 and 1938, supplementing this primary source research with books and articles on Nazi propaganda and American isolationism that I accessed through the library. The study of the AP’s coverage of Nazi Germany is a very new field of history, with almost nothing published on the subject before 2016. I am very proud of the results of my research, and I am indebted to the library and (especially) the archives for access to the invaluable sources that made that research possible
ANALYSIS OF DYNAMIC STABILITY WHILE TEXTING DURING STAIR DESCENT
Get PDFThe purpose of this study was to explore the modifications in saggital and frontal dynamic stability during stair descent while texting to provide a database for guidelines of fall prevention. Participants (n=26; 13 male, 13 female) performed three stair descent trials under texting and No texting task conditions at self-selected speed, respectively. Synchronous kinematics and kinetics were collected by an eight-camera Vicon infrared motion capture system and two force platforms. A paired sample t-test was used to analyze the differences between two task conditions. With the interference of texting, anterior–posterior margin of stability (MOSap) increased in the initiation of double-support phase (DSP), while decreased in the initiation of single-support phase (SSP), medial–lateral MOS (MOSml) decreased in the initiation of SSP. Posterior instability was induced in the initiation of DSP. The initiation of DSP was the most unstable moment and should alert texters, particularly young adults, to potential risk of falling backward during stair descent
DYNAMICS OF A CYCLIC TASK BEFORE AND AFTER A CHANGE IN TASK CONSTRAINT: HORIZONTAL BAR LONGSWING
Get PDFReturning to a consistent technique after a change in skill allows gymnasts to improve routine fluidity. This study investigates the limit cycle dynamics of the mass centre (CM) after a variation in task constraint during the horizontal bar longswing (LS). Gymnasts (n=12) from 3 different age categories completed 3 x 8 consecutive LS with LS four and five as accelerated LS. Senior gymnasts presented the most consistent limit cycle trajectory and lowest correlation dimension (CD) post- compared to pre- task constraint. Senior gymnasts displayed significantly lower CD post- constraint compared to both junior (p = .016) and development gymnasts (p\u3c .001). The increased proficiency attributed to senior gymnasts appears to increase the stability features of the LS limit cycle of the CM angular velocity after an imposed task constraint which may indicate readiness to progress to more complex horizontal bar skills
THE ROLE OF SHOE SOLE DUROMETER ON JUMPING KINETICS
Get PDFThis study investigated the relationship between shoe heel density (HD), toe density (TD) and the peak ground reaction force (GRF) and rate of force development (RFD) during jumping. This study also assessed the reliability of the durometer to assess shoe soles. Subjects included 12 men. Shoe HD and TD were assessed via durometer and kinetics were determined during the countermovement jump on a force platform. A Pearson bivariate correlation analysis was performed. Results reveal that HD was not correlated with GRF (r = -.22, p = .50) or RFD (r = -.14, p = .67). Similarly, TD was not correlated with GRF (r = -.29, p = .37) or RFD (r = -.28, p = .37). Intraclass correlation coefficients for the heel and toe durometer were .95 and .92, respectively. Jumping kinetics were not mediated by shoe sole characteristics, though the durometer was reliable for assessing shoe soles
EFFECTS OF ANTERIOR-POSTERIOR LOAD PLACEMENTS IMPOSED BY A TRANSFORMER BAR ON SQUAT BIOMECHANICS
Get PDFExamining the effect of anterior-posterior load placements imposed by a transformer bar could provide additional options for squatting exercises. The purpose of this study was to quantify trunk and pelvis angles and low back and lower extremity joint moments among the regular back and front squats and four squats with a transformer bar. Twelve males and 12 females performed six different squatting variations with a load of 70% of their one-repetition maximum of the regular front squat: back and front squats with a regular bar, back and front squats with a transformer bar, and squats with more anterior or posterior loads with a transformer bar. Joint angles and moments were extracted at the thigh angle of 70° in the ascending phases, corresponding to a posture close to a parallel squat. Trunk flexion angles were the highest for the transformer bar back squat and transformer bar posterior load squat. The greatest pelvis flexion angles were observed for the regular back squat, transformer bar back squat, and transformer bar posterior load squat. Low back joint moments were the highest for the transformer bar anterior load squat. Hip joint moments were significantly lower for the regular bar front squat compared to the other squat conditions. More posterior load placements resulted in decreased low back moments, increased trunk and pelvis flexion angles, and similar hip and knee moments compared to more anterior load placements. Changing the load placement does not affect low back and lower extremity loading as expected because the trunk and pelvis angles could be adjusted according to load placements. An anterior load placement may result in greater low back moments while a posterior load placement has greater trunk and pelvis flexion, which should be taken into consideration for people with low back impairments