184 research outputs found

    The Spatial Distribution Of OH And CN Radicals In The Coma Of Comet Encke

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    Multiple potential parent species have been proposed to explain CN abundances in comet comae, but the parent has not been definitively identified for all comets. This study examines the spatial distribution of CN radicals in the coma of comet Encke and determines the likelihood that CN is a photodissociative daughter of HCN in the coma. Comet Encke is the shortest orbital period (3.3 years) comet known and also has a low dust-to-gas ratio based on optical observations. Observations of CN were obtained from 2003 October 22 to 24, using the 2.7 m telescope at McDonald Observatory. To determine the parent of CN, the classical vectorial model was modified by using a cone shape in order to reproduce Encke's highly aspherical and asymmetric coma. To test the robustness of the modified model, the spatial distribution of OH was also modeled. This also allowed us to obtain CN/OH ratios in the coma. Overall, we find the CN/OH ratio to be 0.009 +/- 0.004. The results are consistent with HCN being the photodissociative parent of CN, but we cannot completely rule out other possible parents such as CH(3)CN and HC(3)N. We also found that the fan-like feature spans similar to 90 degrees, consistent with the results of Woodney et al..NASAOffice of the Vice President for Research and Economic Development at Mississippi State UniversityMcDonald Observator

    Math, God and Politics—A Fight over Geometry in 19th Century Italy

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    In 1839 a polemic, reminiscent of the Renaissance public challenges over mathematical problems, was issued by the leader of the synthetic school of geometry, Vincent Flauti, to the analytical school, headed by Fortunato Padula. Three geometric problems were proposed, all carefully chosen to guarantee a victory for the synthetic school. The judges were from the Royal Academy of Sciences, men also favorable to the synthetic method. Why then did the analytics take up this challenge, and who were the real victors? This was not just a fight over the ‘correct’ way to do geometry, it was a fight over politics, a changing society, and most importantly, the Godly way to do mathematics. In this talk we will learn the goals and motivations of the synthetic school and the analytical school, the means they used to achieve those goals, and the final outcomes for mathematics and Italy

    Math History Study Abroad Program: Learning Math History in a Cultural Context

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    In January 2011 fifteen Whitworth University mathematics students and I, their professor, traveled through Europe to study the history of mathematics. The goal was to gain an understanding of how mathematical ideas have developed over time; how social, cultural and historical factors have influenced the development of mathematics and conversely, how mathematics contributed to society and human culture. Over a course of three weeks we traveled to three countries and over a half dozen cities, viewing the tools, papers and workbooks or these mathematicians, seeing their engineering and artistic creations, and learning from local experts as they guided us through science museums and archives. The experience helped us to understand the broad roles of mathematics and mathematicians played in the world around them

    A Career Preparation Course for Students in Mathematics and Computer Science

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    As professors, we all want our students to succeed, and to be motivated to study. We all get questions from students that can be boiled down to, What can I do with X degree? Certainly, a quick answer is to point students to career websites, or to send them to the career services department on campus. However, we want to do better than that. We want students to learn how to investigate these future directions, and to have them think about their future more holistically--not just an effort to find a job. To that end, we have developed a course at Whitworth University to help students in mathematics and computer science in their investigations. We help students to learn more carefully about their own strengths and values, and to find careers that match those strengths and values. We provide students with opportunities to consider many kinds of vocational options: industry, graduate school, and mission work. We push students to investigate how their life is affected and influenced doe to these various career directions, and to think further than just how to get their first job. Finally, we encourage students to think more holistically about vocation, and how their own faith and ethical values play an important role in their vocation. In this paper, we discuss the course and its components. When appropriate, we will also discuss how faith and ethics were considered in components

    Regulatory dendritic cell treatment prevents the development of vasopressin-induced preeclampsia

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    The concept that persistent feto-placental intolerance is important in the pathogenesis of preeclampsia (PE) has been demonstrated by our lab and others. Arginine vasopressin (AVP) infusion during pregnancy induces cardiovascular, renal, and immune alterations in mice consistent with human PE. These findings identify AVP as a potential contributor to poor fetal tolerance and the development of PE. In addition to their conventional immuno-stimulatory role, dendritic cells (DCs) also play a vital role in immune tolerance. In contrast to conventional DCs, regulatory DCs (DCregs) express low levels of co-stimulatory markers, produce anti-inflammatory cytokines, induce T regulatory cells, and promote tolerance. In mice, DCregs are able to prevent pro-inflammatory responses and induce antigen-specific tolerance. Given these known functions of DCregs, we hypothesize that DCregs will prevent the development of AVP-induced PE

    Betamethasone: a novel therapeutic intervention for preeclampsia

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    The early pathogenesis of preeclampsia (PE) involves a systemic inflammatory immune response. Recent data demonstrate that increased circulating arginine vasopressin (AVP) in humans is predictive of PE and that infusion of AVP in mouse dams phenocopies the pregnancy-specific cardiovascular and immune alterations observed in human PE. Specifically, AVP suppresses anti-inflammatory cytokines and cells. Betamethasone (BMTZ), commonly given to women at risk for preterm birth, is both an AVP and immune response modulator. We hypothesize that early treatment with BMTZ will prevent the development of AVP-induced PE

    Static urine osmolality with elevated first trimester urine copeptin in human preeclampsia

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    We have previously shown that maternal plasma copeptin (CPP), as a marker of vasopressin, is highly predictive of preeclampsia (PE) in the first trimester and remains elevated throughout pregnancy. Furthermore, in maternal urine samples we demonstrated that CPP was also significantly elevated in the first trimester in women who later developed PE. Because a urine dipstick test could be easily used in the clinic, we sought to validate this finding in a new and expanded cohort of samples and to determine whether these changes persist throughout pregnancy. In addition, to begin to address the mechanism for this difference, we also assessed urine osmolality to further probe renal function

    Detection and Identification of Salmonella enterica, Escherichia coli, and Shigella spp. via PCR-ESI-MS: Isolate Testing and Analysis of Food Samples

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    An assay to identify the common food-borne pathogens Salmonella, Escherichia coli, Shigella, and Listeria monocytogenes was developed in collaboration with Ibis Biosciences (a division of Abbott Molecular) for the Plex-ID biosensor system, a platform that uses electrospray ionization mass spectroscopy (ESI-MS) to detect the base composition of short PCR amplicons. The new food-borne pathogen (FBP) plate has been experimentally designed using four gene segments for a total of eight amplicon targets. Initial work built a DNA base count database that contains more than 140 Salmonella enterica, 139 E. coli, 11 Shigella, and 36 Listeria patterns and 18 other Enterobacteriaceae organisms. This assay was tested to determine the scope of the assay\u27s ability to detect and differentiate the enteric pathogens and to improve the reference database associated with the assay. More than 800 bacterial isolates of S. enterica, E. coli, and Shigella species were analyzed. Overall, 100% of S. enterica, 99% of E. coli, and 73% of Shigella spp. were detected using this assay. The assay was also able to identify 30% of the S. enterica serovars to the serovar level. To further characterize the assay, spiked food matrices and food samples collected during regulatory field work were also studied. While analysis of preenrichment media was inconsistent, identification of S. enterica from selective enrichment media resulted in serovar-level identifications for 8 of 10 regulatory samples. The results of this study suggest that this high-throughput method may be useful in clinical and regulatory laboratories testing for these pathogens

    Phase II Trial of IL-12 Plasmid Transfection and PD-1 Blockade in Immunologically Quiescent Melanoma.

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    PurposeTumors with low frequencies of checkpoint positive tumor-infiltrating lymphocytes (cpTIL) have a low likelihood of response to PD-1 blockade. We conducted a prospective multicenter phase II trial of intratumoral plasmid IL-12 (tavokinogene telseplasmid; "tavo") electroporation combined with pembrolizumab in patients with advanced melanoma with low frequencies of checkpoint positive cytotoxic lymphocytes (cpCTL).Patients and methodsTavo was administered intratumorally days 1, 5, and 8 every 6 weeks while pembrolizumab (200 mg, i.v.) was administered every 3 weeks. The primary endpoint was objective response rate (ORR) by RECIST, secondary endpoints included duration of response, overall survival and progression-free survival. Toxicity was evaluated by the CTCAE v4. Extensive correlative analysis was done.ResultsThe combination of tavo and pembrolizumab was well tolerated with adverse events similar to those previously reported with pembrolizumab alone. Patients had a 41% ORR (n = 22, RECIST 1.1) with 36% complete responses. Correlative analysis showed that the combination enhanced immune infiltration and sustained the IL-12/IFNγ feed-forward cycle, driving intratumoral cross-presenting dendritic cell subsets with increased TILs, emerging T cell receptor clones and, ultimately, systemic cellular immune responses.ConclusionsThe combination of tavo and pembrolizumab was associated with a higher than expected response rate in this poorly immunogenic population. No new or unexpected toxicities were observed. Correlative analysis showed T cell infiltration with enhanced immunity paralleling the clinical activity in low cpCTL tumors
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