251 research outputs found

    Measuring Accessibility and Explaining Trends in Commute Mode Choice in Washington, D.C. from 1970 - 2000

    Get PDF
    This study attempts to find a correlation between commuting modes in Washington DC and characteristics of the city and the people that they serve. It investigates why some census tracts have experienced increases in the commuting share of alternative transportation, such as public transit, walking, and bicycling, while others haven\u27t. Findings demonstrate that demographic variables such as percent Hispanic and foreign born were the strongest predictors of change in commute mode share followed by distance to train station. Land use variables demonstrated weak correlations with variations in mode share due most likely to a lack of density gradient within the study area. The creation of variables to determine land use mix by census tract posed technical challenges as well. Recommendations include policy addressing rising demand for more diverse transportation systems be implemented and further research be conducted on creating more accurate land use variables to include in the model

    Without the White Coat: An Analysis of Pathographies by Physicians with Cancer

    Get PDF
    https://digitalcommons.unmc.edu/emet_posters/1000/thumbnail.jp

    Road and bridge construction across gypsum karst in England

    Get PDF
    Gypsum karst problems in the Permian and Triassic sequences of England have caused difficult conditions for bridge and road construction. In Northern England, the Ripon Bypass crosses Permian strata affected by active gypsum karst and severe subsidence problems. Here, the initial borehole site investigation for the road was supplemented by resistivity tomography studies. The roadway was reinforced with two layers of tensile membrane material within the earth embankment. This will prevent dangerous catastrophic collapse, but will allow sagging to show where problems exist. The River Ure Bridge was constructed across an area of subsidence pipes filled with alluvial deposits. It was built with extra strength, larger than normal foundations. If one pier fails, the bridge is designed for adjacent arches to span the gap without collapse. The bridge piers are also fitted with electronic load monitoring to warn of failure. In the Midlands area of England, road construction over Triassic gypsum has required a phase of ground improvement on the Derby Southern Bypass. Here, the gypsum caps a hill where it was formerly mined; it dips through a karstic dissolution zone into an area of complete dissolution and collapse. The road and an associated flyover were built across these ground conditions. A major grouting program before the earthworks began treated the cavities in the mine workings and the cavernous margin of the gypsum mass. Within the karstic dissolution zone, gypsum blocks and cavities along the route were identified by conductivity and resistivity geophysical surveys, excavated and backfilled. In the areas of complete dissolution and collapse, the road foundation was strengthened with vibrated stone columns and a reinforced concrete road deck was used

    Generalizations of the Matching Polynomial to the Multivariate Independence Polynomial

    Get PDF
    We generalize two main theorems of matching polynomials of undirected simple graphs, namely, real-rootedness and the Heilmann-Lieb root bound. Viewing the matching polynomial of a graph GG as the independence polynomial of the line graph of GG, we determine conditions for the extension of these theorems to the independence polynomial of any graph. In particular, we show that a stability-like property of the multivariate independence polynomial characterizes claw-freeness. Finally, we give and extend multivariate versions of Godsil's theorems on the divisibility of matching polynomials of trees related to GG.Comment: This research was supported by NSF Grant CCF-155375, 20 page

    Symmetrical Drug-Related Intertriginous and Flexural Exanthema Induced by Cellulitis Prophylaxis

    Get PDF
    Penicillin VK and hydroxyzine are typically well-tolerated antipruritic agents that are indicated in the prophylaxis of cellulitis. We herein report a case of a unique rash occurring during penicillin VK and hydroxyzine treatment in combination with the ingestion of cashews. A 77-year-old male presented with new onset rash. Eleven days after the administration of penicillin VK and hydroxyzine for cellulitis prophylaxis, he developed a symmetric, erythematous, scaling rash on his buttocks and perineal region with associated pruritus and bleeding without fevers, chills, adenopathy, night sweats, or any other symptoms. He was diagnosed with symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) secondary to systemic treatment, an adverse drug reaction that presents as an erythematous rash involving the skin folds. The condition is also known as “baboon syndrome,” as it predominately affects the buttocks. A good outcome was achieved due to a thorough history and physical, timely diagnosis, and cessation of the offending agents

    Retropharyngeal Abscess and Pott’s Disease Due to Tuberculosis: A Case Report

    Get PDF
    Introduction: Extrapulmonary mycobacterial infection can lead to vertebral spondylitis and osteomyelitis (Pott’s disease). Retropharyngeal abscess with concurrent spinal osteomyelitis is a rare presentation of tuberculosis in the US. Chart review on a patient was completed, and the relevant published literature was reviewed. Case Presentation: A previously healthy 34-year-old male originally from Sudan presented to an outside hospital with a 2-month history of neck pain, sore throat, odynophagia, fevers, and chills. MRI showed a retropharyngeal abscess and suspected cervical spine osteomyelitis. Acid-fast bacillus (AFB) smear was positive from a neck drain specimen, but sputum was negative. Chest imaging did not show findings consistent with pulmonary tuberculosis. He was treated with rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) along with moxifloxacin and linezolid due to concern for possible multidrug resistant tuberculosis and transferred to our center for further care. Culture isolated Mycobacterium tuberculosis. CT neck showed vertebral tuberculous osteomyelitis (Pott’s disease) of C1-C3 with a multiloculated retropharyngeal and prevertebral abscess (Figure 1). The patient was taken to the OR for posterior spinal fusion from occiput to C4 and transoral incision and drainage of the abscess. The post-operative course was uneventful, and moxifloxacin and linezolid were discontinued when Xpert MTB/RIF test revealed rifampin susceptibility. At follow-up the patient’s symptoms had resolved. Patient consent was obtained to utilize this case for educational purposes. Conclusions: This report presents the multidisciplinary treatment of this patient requiring infection control measures and antibiotic therapy by infectious disease, posterior spine fusion by orthopedic surgery, and retropharyngeal abscess drainage by otolaryngology
    • …
    corecore