Measuring the Orbital Angular Momentum of Electron Beams

The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam are fundamentally important and a necessary next step. We demonstrate the measurement of electron beam OAM through a variety of techniques. The use of forked holographic masks, diffraction from geometric apertures, diffraction from a knife-edge and the application of an astigmatic lens are all experimentally demonstrated. The viability and limitations of each are discussed with supporting numerical simulations.Comment: 5 pages, 4 figurs

Enhancing General Chemistry Labs to Construct Engaging, Colorful Experiments

General Chemistry I (CHEM 121) sets the foundation for the chemistry education of Valparaiso students; therefore, it is critical that the CHEM 121 lecture and laboratory courses provide rich learning experiences that are meaningful, focused and both academically and visually engaging. In this project, two new or significantly revised laboratory experiments were incorporated into the curriculum during the Spring 2018 semester for the first time: 1) The Limiting Reagent in Action: Determining the Formula of a Precipitate and 2) The Analysis of Microplastic Pollution in Local Soil. The common goal of both labs were to increase student understanding of challenging general chemistry concepts by enhancing student engagement. In the case of Experiment 1, this was accomplished by improving the visual appeal of the reactions employed; in the case of Experiment 2, this was accomplished by directly connecting course material to study real-world pollution problems facing NW Indiana. Results of this experimentation and its impact on student learning in CHEM 121 are described

Leggett's bound for amorphous solids

We investigate the constraints on the superfluid fraction of an amorphous solid following from an upper bound derived by Leggett. In order to accomplish this, we use as input density profiles generated for amorphous solids in a variety of different manners including by investigating Gaussian fluctuations around classical results. These rough estimates suggest that, at least at the level of the upper bound, there is not much difference in terms of superfluidity between a glass and a crystal characterized by the same Lindemann ratio. Moreover, we perform Path Integral Monte Carlo simulations of distinguishable Helium 4 rapidly quenched from the liquid phase to very lower temperature, at the density of the freezing transition. We find that the system crystallizes very quickly, without any sign of intermediate glassiness. Overall our results suggest that the experimental observations of large superfluid fractions in Helium 4 after a rapid quench correspond to samples evolving far from equilibrium, instead of being in a stable glass phase. Other scenarios and comparisons to other results on the super-glass phase are also discussed.Comment: 11 pages, 5 figure

Shortening Wait-Times in the Emergency Department

Many Americans visit the Emergency Department (ED) every day for a variety of reasons. Some are extreme emergencies while others could be handled by a primary care provider (PCP). However, the EDs throughout the United States and other countries throughout the world are consistently known for their extended wait-times. Evidence has shown the average ED wait-time is about 145 minutes, being significantly longer in other states. In a state of emergency, 145 minutes could mean life or death. Shortening wait-times in the ED is crucial to saving lives, efficiently utilizing staff members, and satisfying patient needs. In this project, various methods of ED organization will be examined such as: the lean principles, diversion, and the queuing method. There are numerous theories on managing patient flow such as: the lean principles, diversion, and the queuing method. Additionally, ED nurses and ED patient perspectives have been documented and will be examined to see if there is a unique perspective on how to manage ED patient flow better from those around it often. Once the various methods are examined, a proposal will be made on the best way to shorten wait-times in the ED. The methods will be analyzed by looking at the wait-time data and evaluating effectiveness. Keywords: Emergency Department, wait-times, patient-flo

Impacts of Beef Concentrated Animal Feeding Operations on Environmental Sustainability in the United States and Practices for Improvement

The geographic concentration of beef concentrated animal feeding operations [CAFOs] has changed the landscape of environmental sustainability for agriculture in the United States. As land availability has decreased, operations have struggled to maintain feasible practices to minimize environmental detriment. The United States Environmental Protection Agency [EPA] imposed rules to be followed as a means of mitigation, but the fast-paced rate of change minimizes effectiveness. The overall environmental sustainability of beef CAFOs has shifted from historical rates, leading to a need for reassessment. Part of this reassessment will include stronger environmental practices to be considered for implementation. I explored the role of manure management practices in CAFOs to evaluate the ways in which these practices contribute to water pollution of nearby sources. Additionally, I investigated what transportation of manure to off-site locations and nutrient management plans [NMPs] can do in relation to rebuilding the health of soil and aquatic ecosystems. The three aforementioned topics are dominated by land availability, so I delved into the impact that the modern decrease of land space plays on overall manure management practice efficiency. Dietary manipulation was also studied because of its relationship with nutrient excess in manure and maintaining animal productivity. In addition to this, cattle-based emissions were considered as they heavily result from feed digestibility. I lastly researched the ways in which water quality is impaired by CAFO functions and how that translates to surrounding lands, aquatic ecosystems, and even human health. The primary impacts of beef CAFOs on environmental sustainability result from decreased land availability. This has led to nutrient overloading from manure and degraded water quality, causing the need for alternative practices. Changing animal diet to increase feed efficiency, transporting manure off-site, and using phosphorus-based nutrient management plans are practices with the greatest promise for increasing environmental sustainability

Ubiquinol Reduces Muscle Wasting but Not Fatigue in Tumor-Bearing Mice

Purpose: Fatigue is the most common and distressing symptom reported by cancer patients during and after treatment. Tumor growth increases oxidative stress and cytokine production, which causes skeletal muscle wasting and cardiac dysfunction. The purpose of this study was to determine whether treatment with the antioxidant ubiquinol improves muscle mass, cardiac function, and behavioral measures of fatigue in tumor-bearing mice. Method: Adult female mice were inoculated with colon26 tumor cells. Half the control and tumor-bearing mice were administered ubiquinol (500 mg/kg/day) in their drinking water. Voluntary wheel running (i.e., voluntary running activity [VRA]) and grip strength were measured at Days 0, 8, 14, and 17 of tumor growth. Cardiac function was measured using echocardiography on Day 18 or 19. Biomarkers of inflammation, protein degradation, and oxidative stress were measured in serum and heart and gastrocnemius tissue. Results: VRA and grip strength progressively declined in tumor-bearing mice. Muscle mass and myocardial diastolic function were decreased, and expression of proinflammatory cytokines was increased in serum and muscle and heart tissue on Day 19 of tumor growth. Oxidative stress was present only in the heart, while biomarkers of protein degradation were increased only in the gastrocnemius muscle. Ubiquinol increased muscle mass in the tumor-bearing and control animals but had no effect on the expression of biomarkers of inflammation, protein degradation, or oxidative stress or on behavioral measures of fatigue