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The Effect of Caffeine on Shot Accuracy and Power in Male Collegiate Lacrosse Players
No full textCaffeine is a stimulant that is becoming more commonly used in sports and athletic events in an effort to increase performance and decrease effects of fatigue. The purpose of this study was to examine the effect of caffeine on sports performance, measured in shot accuracy and maximum shot power, of collegiate lacrosse players. The design of this study evaluated if caffeine ingestion (4 mg/kg) would significantly affect lacrosse shot power and accuracy compared to a placebo. This was a double-blind study. Following one familiarization trial, participants were randomly assigned to ingest either the caffeine or placebo in a double-blind counter-balanced manner on one of two testing days. Shot speed was measured using a radar gun while shot accuracy was assessed using a net cover with holes in each corner. The participants shot from a distance of 10 yards. Total shots made compared to shots attempted was measured. The data gathered yielded no significant differences between groups, although there was a trend towards an increase in maximum shot speed after caffeine use (Placebo: 81.0 ± 7.1mph, Caffeine: 83.2 ± 7.0mph, p=.115). There was no difference found for shot accuracy with and without caffeine (Placebo: 13.8 ± 4.1, Caffeine: 14.1 ± 4.5, p=.809). While there was little evidence to support caffeine increasing lacrosse sport performance from this study, further research using a larger sample size and more trials might yield more significant results
The Impact of the U.S. State Department Think Again Turn Away Campaign on ISIS Recruitment
No full textSince 9/11, technology, social media, and the Internet have become vehicles for the recruitment of extremist supporters. With the increased threat of the Islamic State of Iraq and Syria (ISIS) in the Middle East, federal agencies and civilians alike have recognized the need for digital counter-messaging to oppose extremist messages. In December 2013, the U.S. State Department launched its “Think Again Turn Away” campaign. This program increased the social media presence of the State Department, leading to the production of anti-ISIS media. By analyzing ISIS recruitment media and American counter-messaging, this project determines the impact of the “Think Again Turn Away” campaign on ISIS recruitment
The Impact of U.S. Defense Spending on Long Term Economic Growth
No full textThere is much debate on the impact and effects the United States defense spending has on its economy. This paper furthers that discussion by asking specifically if there is a positive correlation between level of defense spending across multiple categories and US economic stability and growth. Using two models for measuring spending impact on economic growth—the Roma Model and the Production Model—and looking at the impacts of technological advancements made by military contractors, my research shows large defense spending is necessary to prevent recession and to foster growth in the US economy. Thus, I show that higher levels of federal defense spending most likely lead to positive long-term economic output and growth
Trace Elemental Analysis of Copper Inclusions in the Portage Lake Volcanics Series of the Keweenaw Peninsula, MI Using Particle-Induced X-ray Emission Spectroscopy (PIXE)
No full textThe Portage Lake Volcanics is a mid-Proterozoic series made up of over 200 individual subaerial thoeiilitic basaltic flows, which contain extensive amygdaloidal and brecciated flow tops in addition to interflow conglomerates, hosting the secondary copper deposits that make the Keweenaw Peninsula region of Michigan famous. The intent of this study is to explore variations in the trace elemental composition of copper deposits in the area and explore possible geological implications of such variations. Thick sections of conglomerates and basalts containing copper inclusions from the Centennial, Calumet & Hecla, Phoenix, and Allouez mines, among others, were analyzed using particle-induced x-ray emission spectroscopy. PIXE was performed in the Hope College Ion Beam Analysis Laboratory using a 1.7MV Pelletron tandem particle accelerator. The ion beam was focused on copper inclusions and spectra were collected and analyzed using gupix software. Ratios of trace nickel, silver, and arsenic to copper were calculated and compared across different inclusions in a single sample and across samples from different geographic locations, formations, and mine depths. Results show some variation in elemental ratios within samples, and greater variation across samples from different mines, formations, and depths. Elemental compositions are likely subject to a variety of factors influencing local conditions in copper mineralization
What Makes Lake Michigan’s Coastal Dunes Migrate? Investigating the Triggers of Dune Mobility in Lake Michigan’s Dunes Using a Multi-proxy Study of a Coastal Dune Lake
No full textAeolian studies of Lake Michigan’s coastal dunes have shown periods of dune mobility and stability in the last 6,000 years. However, the triggering mechanisms for these changes in aeolian activity are not well understood. Small lakes located downwind of dune complexes contain aeolian sand and biological proxies that can provide both dune activity and independent paleoenvironmental data. We undertook a multi-proxy study of a lake-sediment-core collected from Gilligan Lake, located adjacent to a large coastal dune complex in Allegan County, Michigan, to reconstruct these histories. We collected a 7.5-cm-diameter vibracore and subsampled in 1 cm3 aliquots for percent sand, charcoal abundance, and pollen identification analyses. Sand concentrations vary on two different scales. Intervals of generally high, intermediate, and low sand persist for intervals of ~ 300–600 years with smaller fluctuations occurring at intervals of 20–100 years. A pattern between the sand concentrations and the different charcoal morphologies was noted. The period of overall high sand concentration is correlated with low abundance of charcoal threads and sheets and high abundances of charcoal chunks. This increase could indicate an increase in the amount of fire. The larger scale period of high sand concentrations is correlated with relatively high abundances of charcoal chunks, suggesting that periods of higher dune activity may be correlated with a higher incidence of fire. The larger scale period of low sand concentrations is correlated with relatively low abundances of oak, hickory, birch, and fir pollen and high abundances of maple, beech, pine, and spruce pollen. The pollen record suggests an expansion of the maple-beech climax community during periods of low dune mobility. Shorter scale fluctuations in sand concentrations do not correlate with any of the pollen or charcoal proxies investigated
Differential PIXE Analysis of Multi-layer Auto Paint
No full textDifferential Particle Induced X-ray Emission (DPIXE) is a technique developed to analyze multi-layered samples in a non-destructive manner. Analysis of auto paint, in particular, is beneficial in legal cases involving automobile crimes. Particle Induced X-ray Emission (PIXE) involves particle beams produced by an ion beam accelerator to analyze the concentration of elements present in one or more layers. As the beam penetrates into the sample, characteristic x rays of various energies are emitted which correspond to different elements in the sample. DPIXE involves varying the beam energy so the beam penetrates to different depths within the sample, emitting x rays only from the layers through which the beam has passed. Quantitative analysis is made easier by first taking measurements of the thickness of each layer. A Scanning Electron Microscope (SEM) with Energy Dispersive Spectroscopy (EDS) capabilities allows us to view a cross-section of paint and measure the thickness of each layer, as well as earn a better understanding of which layers hold the major elements within the sample. A careful combination of the SEM, EDS and DPIXE data is required to obtain accurate concentrations of elements in a sophisticated peak fitting program (GeoPIXE) with calculations of energy loss as the beam penetrates to different depths and reabsorption of x rays as they travel out of the sample towards the detector. This technique has shown to produce reasonable results when analyzing samples containing layers of uniform thickness
PIXE-NRA Analysis to Determine Metalloprotein Complete Stoichiometry
No full textWhile approximately a third of all proteins are metalloproteins, their stoichiometric ratios are still largely unknown. Current elemental analysis procedures are capable of determining which metals are in a protein, but it is difficult to determine how many. To address this, an ion beam analysis method is being developed using Particle-Induced X-ray Emission (PIXE) and Nuclear Reaction Analysis (NRA). PIXE determines the elemental composition of the sample and provides a metal-to-metal ratio. However, this is not the desired ratio of metal per protein. NRA uses Rutherford scattering cross-sections to determine an exact ratio of number of atoms to number of proteins. When PIXE and NRA are used in conjunction, it is possible to accurately determine the desired metal-to-protein stoichiometric ratio. In order to ensure accuracy, this method is being developed on Cyanocobalamin (B12) and Cytochrome C which have known stoichiometries. This method will provide us with a standard such that it will be possible to obtain the atomic ratios of additional metalloproteins with confidence. Recent advances include revising sample preparation, refining the substrate, and improving data analysis
Tipping the Scales: Do Gasoline Prices Fuel the Obesity Epidemic?
No full textAbove normal body mass index (BMI) has become the norm for adults in the U.S., with overweight or obesity affecting two thirds of adults. Now, with gasoline prices falling, American households saved $700 in annual gasoline expenditures in 2015 relative to 2014, it raises the question of whether this savings will translate into more expenditures on healthy activities. This paper examines the effects of changing gasoline prices on the obesity epidemic in the United States. I model consumer behaviors related to obesity within a rational choice framework allowing that gasoline prices might change mode of transportation through a substitution effect and/or any number of physical activities that an individual may participate in more or less due to an overall income effect associated with changing gasoline prices. Cross-sectional data from the American Time Use Survey (ATUS) over 2006 to 2008, provide detailed information on the amount of time Americans spend in a wide variety of activities including shopping, housework, and physical exercise, and incorporates individuals’ BMI. Also using monthly state-level gasoline prices from the U.S. Energy Information Administration (EIA), this study employs year and state-level fixed effects to identify a casual connection between gasoline prices and obesity
News from Hope College, Volume 48.2: Winter 2016
Get PDFhttps://digitalcommons.hope.edu/news_from_hope_college/1243/thumbnail.jp
The Anchor, Volume 129.15: February 3, 2016
Get PDFThe Anchor began in 1887 and was first issued weekly in 1914. Covering national and campus news alike, Hope College’s student-run newspaper has grown over the years to encompass over two-dozen editors, reporters, and staff. For much of The Anchor\u27s history, the latest issue was distributed across campus each Wednesday throughout the academic school year (with few exceptions). In recent years The Anchor moved to monthly print issues and a more frequently updated website. The Anchor is now published in print twice per academic semester. Occasionally, the volume and/or issue numbering is irregular