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Compton Scattering Cross Sections in Strong Magnetic Fields: Advances for Neutron Star Applications
No full textVarious telescopes including RXTE, INTEGRAL, Suzaku, and Fermi have detected steady non-thermal X-ray emission in the 10 - 200 keV band from strongly magnetic neutron stars known as magnetars. Magnetic inverse Compton scattering is believed to be a leading candidate for the production of this intense X-ray radiation. Generated by electrons possessing ultra-relativistic energies, this leads to attractive simplifications of the magnetic Compton cross section. We have recently addressed such a case by developing compact analytic expressions using correct spin-dependent widths acquired through the implementation of Sokolov & Ternov (ST) basis states, focusing specifically on ground state-to-ground state scattering. Such scattering in magnetar magnetospheres can cool electrons down to mildly-relativistic energies. Moreover, soft gamma-ray flaring in magnetars may well involve strong Comptonization in expanding clouds of mildly-relativistic pairs. These situations necessitate the development of more general magnetic scattering cross sections, where the incoming photons acquire substantial incident angles relative to the field in the rest frame of the electron, and the intermediate state can be excited to arbitrary Landau levels. The cross sections treat the plethora of harmonic resonances associated with various cyclotron transitions between Landau states. Polarization and spin dependence of the cross section for the four scattering modes is compared with the non-relativistic Thompson cross section with classical widths. The work here is purely analytical and is done to give compact analytical expressions for the Compton cross sections. Results will find application to various neutron star problems, including computation of Eddington luminosities and polarization mode-switching rates in transient magnetar fireballs
Legg-Calvé-Perthes Disease: A Case Study
No full textLegg-Calve-Perthes disease is a form of osteonecrosis in children occurring in the head of the femur. The name originated from Arthur Legg, an American orthopedic surgeon, Jacques Calve, a French orthopedic surgeon, and Georg Perthes, a German orthopedic surgeon. The disease results in a disruption of blood supply to the long bone of the leg, which in turn can then lead to localized cell death. The loss of bone tissue can cause instability in the hip producing an antalgic gait, pain, soft tissue dysfunction, and overall functional disability. The strength and range of motion of the muscles in the buttock and upper leg are decreased over time without treatment. The main treatment options are a wait-and-see approach, non-surgical with rehabilitation, and surgical with repair. The two main surgical options involve cutting and releasing the tendoninous tissue or cutting and repositioning the bone to reduce stress. Various treatment and surgical options will be discussed regarding this particular case study of a 9-year-old female. The study looks into the specifics of the case and the treatments that she received
Senior Case Presentation: Brostrom Ankle Reconstruction on Chronic Ankle Injury
No full textLateral ankle injuries are one of the most common injuries in sports today. These injuries commonly occur in sports due to “rolling of the ankle” or inversion. The Brostrom ankle surgery is a reconstruction of the lateral ankle ligaments after the ankle has developed chronic instability. This condition can be painful, debilitating and could lead to further trauma to the ankle structure or lower extremity. This surgery option will only be used after conservative treatments have not properly strengthened the ligaments and overall lateral ankle complex. The main ligaments of the lateral complex consist of the anterior talofibular, calcaneofibular, and the posterior talofibular ligaments. The specific clinical ligamentous stress tests to determine damage to these ligaments include the Anterior Drawer test, Kleigers test, and the Talar Tilt test. If these tests are positive or complaints of dysfunction are reoccurring, the Brostrom surgery is performed. An MRI is the gold standard for identifying structural damage and determining severity of the ankle trauma. Rehabilitation will be used as a conservative treatment before surgery is prescribed. The rehabilitation will also continue after the surgery in order to restore the strength, range of motion, and mobility. A case study of a collegiate men’s basketball player will be reviewed in regards to chronic ankle instability and surgical repair
Bilateral Chronic Exertional Compartment Syndrome in a 21- Year-Old Female: A Case Study
No full textCompartment Syndrome occurs and develops when swelling and bleeding occur in the compartments of the lower leg, and pressure within the muscle builds to high and dangerous levels. For this case, it is also important to understand the anatomy of the lower leg, as well as the possible differential diagnoses. The anatomy of the lower leg consists of four major compartments, comprised of muscles, nerves, arteries, and veins, which are surrounded by fascia. Pressure that results from this condition can decrease blood flow, preventing nourishment and oxygen from reaching distal cellular structures. There are also multiple differential diagnoses involved in this case, which play a large role in how the patient may receive treatment. In this case, a stress fracture, medial tibial stress syndrome, and compartment syndrome were all possible diagnoses. It is important to be aware of the symptoms the athlete presents in order to rule out other conditions. There are two general treatment options for this condition: a conservative and a surgical option. The conservative option consists of cryotherapy, orthotic fitting, reduction of training volume, and potentially rest. The surgical option consists of a fasciotomy, which requires an incision into each involved compartment in order to reduce the level of pressure. However, in this athlete specifically, three surgical operations were necessary over a five year period. Her chronic exertional compartment syndrome was recurring, and the athlete would only remain symptom free for a few months after a surgical operation was performed. An overview of the condition and outcomes from this case will be presented
“Remember, Unite, Renew”: A Preliminary Situation Analysis of Nyamata, Rwanda
No full textHope College has had a presence in the community of Nyamata, Bugesera, Rwanda (Nyamata) since 2008, and the student organization, BeHope Rwanda Project (BeHope), has been a significant point of connection between Hope College and Nyamata. This preliminary situation analysis was designed to provide the opportunity for members of Nyamata’s community to have their voices heard with regard to future engagement with Hope College in order to support Hope’s efforts to better align with community-identified needs, preferences, and practices. This project was a qualitative, exploratory investigation of Nyamata, Rwanda and the surrounding area. In this project, students from BeHope investigated community members’ perspectives regarding Nyamata’s strengths, needs, opportunities, trends, and resources, as well as the role of Hope College in their community. The research team used open and axial coding to identify key themes in members’ responses. The organizing theme was identified as surviving vs. thriving over time: community/social factors that related to the idea of “surviving” were especially characteristic of the pastpresent, while “thriving” responses expressed desired/intended changes that are either presently occurring in an early stage or are hoped for at some point in the future. Suggestions for future engagement between Hope College and Nyamata, Rwanda include: expanding Hope College involvement in Rwanda (including conducting a full Situation Analysis); beginning to work more with the local government, as they have reliable information about the communities’ needs and they know what is important and urgent; and continuing to increase the partnership circle by giving the Hope community opportunities to get involved (e.g. Rwanda May Term) and by getting involved in the community at-large outside of NCV
The Anchor, Volume 129.02: September 9, 2015
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
International Adoption: Parent Perspectives
Get PDFThis project, “International Adoption: Parent Perspectives” is a follow-up of the Milk and Medicine Evaluation (2013). The Milk & Medicine Program is a supplemental feeding program for orphans and vulnerable children (OVC) in Lusaka, Zambia. An evaluation of the program in May 2013 included a trip to Zambia and provided insight into variables surrounding orphan care, systemic and governmental issues, and the depth of need for sustainable global development. The program evaluation exposed the need for continued research in the field of social work and OVC care, while equipping the research team, made up of two social work faculty and two undergraduate student research assistants, with excellent analytical and pragmatic research skills. The experience working on the Milk and Medicine Project in Zambia combined with personal family international adoptive experience led to an interest in exploring the world of international adoption - one aspect on the vast spectrum of OVC care. We were specifically interested in the perspective of adoptive parents. Using a snowball method of sampling, twelve interviews were conducted with parents who have adopted internationally, representing seven countries. This exploratory study aimed to learn more about the perspective of adoptive parents concerning three categories that framed our thematic outcomes: pre-adoption, the adoption process, and post-adoption. Derived from Grounded Theory and an Open Coding process, results grouped around the three categories and nineteen micro themes, some of which included: motivation to adopt, resilience, grief and loss, attachment, and post-adoption support. Given the exploratory nature of the study and its interdisciplinary and complex nature, there is a large platform for future research
Stealing Home: Jackie Robinson, the Pittsburgh Courier, and Integration through Baseball
Get PDFThis project traces the story of Jackie Robinson’s first two years in professional baseball, from 1945 to 1947, as told by the activist paper the Pittsburgh Courier. The Courier, the largest weekly paper in America at the time with a primarily African American readership, had a history of campaigning for the integration of baseball, and forged a direct relationship with Robinson through the initiative of one of its editors, Wendell Smith. Over the course of Robinson\u27s quest for the major leagues, Smith and other writers for the Courier, including Robinson himself, utilized rhetoric that connected Robinson’s actions on the diamond to the greater fight for racial equality. Based primarily on research of the Courier’s sports section, this project analyzes how the paper used gameplay as a crucial tool in the paper\u27s civil rights activism, fighting for integration in baseball and beyond