2,336 research outputs found

    Lyman alpha line shapes from electron impact H2 dissociative processes in the Jovian auroral zone

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    Over the past two years several Lyman alpha line profile spectra of Jupiter were obtained using the International Ultraviolet Explorer (IUE) telescope. Several different regions of the planet were observed including the auroral zone, the low and mid latitudes, and the equatorial region which includes the Lyman alpha bulge region. These results have presented a very interesting picture of atomic hydrogen on Jupiter with explanations that range from ion outflow in the auroral zone to large thermospheric winds at low and mid latitudes. New data are needed to address the outstanding questions. Almost certainly, high resolution spectra from the Hubble Space Telescope will play a role in new observations. Better data also require better models, and better models require new laboratory data as inputs. The purpose of this program is two-fold: (1) to introduce a method by which new laboratory electron impact measurements of H2 dissociation can be used to calculate both the slow and fast H(S-2) and H(P-2) fragments in an H2 atmosphere; and (2) to determine the predicted Lyman alpha line shape that would result from electron impact production of these dissociative fragments in the Jovian auroral zone

    An updated hydrocarbon photochemical model for the Jovian atmosphere from the troposphere through the homopause: A prelude to Galileo

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    A photochemical model for the atmosphere of Jupiter, including 1-D vertical eddy diffusive transport, was developed. It extends from the upper troposphere through the homopause. The hydrocarbon chemistry involves species containing up to four carbon atoms (and polyynes through C8H2). The calculations show that a large fraction of photochemical carbon may be contained in molecules with more than two carbon atoms. At the tropopause, C2H6 is the major photochemical species and C2H2, C3H8, and C4H10 are of comparable abundance and down from C2H6 by a factor of ten. These species may be detectable with the mass spectrometer of the Galileo Probe. The vertical distributions of the photochemical species are sensitive to the magnitude of eddy diffusive mixing in the troposphere and stratosphere and the details of the interface region

    Latest results on Jovian disk X-rays from XMM-Newton

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    We present the results of a spectral study of the soft X-ray emission (0.2-2.5 keV) from low-latitude (`disk') regions of Jupiter. The data were obtained during two observing campaigns with XMM-Newton in April and November 2003. While the level of the emission remained approximately the same between April and the first half of the November observation, the second part of the latter shows an enhancement by about 40% in the 0.2-2.5 keV flux. A very similar, and apparently correlated increase, in time and scale, was observed in the solar X-ray and EUV flux. The months of October and November 2003 saw a period of particularly intense solar activity, which appears reflected in the behaviour of the soft X-rays from Jupiter's disk. The X-ray spectra, from the XMM-Newton EPIC CCD cameras, are all well fitted by a coronal model with temperatures in the range 0.4-0.5 keV, with additional line emission from Mg XI (1.35 keV) and Si XIII (1.86 keV): these are characteristic lines of solar X-ray spectra at maximum activity and during flares. The XMM-Newton observations lend further support to the theory that Jupiter's disk X-ray emission is controlled by the Sun, and may be produced in large part by scattering, elastic and fluorescent, of solar X-rays in the upper atmosphere of the planet.Comment: 17 pages, 7 figures, accepted for publication in a special issue of Planetary and Space Scienc

    BE YOUR OWN BOSS: A CHRONIC DISEASE SELF-MANAGEMENT PROGRAM

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    poster abstractObjective: Describe the pilot of a peer-led chronic disease self-management workshop for youth aged 13-24 years old. Background: Fifteen to eighteen percent of children in the United States live with a chronic health condition (Perrin et al., Journal of the American Medical Association 2007, 297:2755). The Stanford chronic disease self-management program (CDSMP) has demonstrated improved self-care and health outcomes in older adults. Alberta Health Services has adapted this program from Stanford University for youth and young adults. CYACC is col-laborating with Alberta to evaluate the effectiveness of the adapted version in adolescents and young adults. Methods: Train the trainer sessions were completed to develop an initial cadre of lay leaders to implement the workshop sessions. Participants with any chronic condition attend 2 hour peer-led sessions once per week for six weeks. During the sessions, individuals with a variety of chronic diseases learn the skills needed in self-management of their condition and mainte-nance of general well-being and life’s activities. Data is collected on self-efficacy, pain, adherence, and other outcomes through pre- and post- as-sessment surveys. Results: Fourteen individuals participated in the pilot phase of the pro-gram; 5 in Lafayette, IN and 8 in Indianapolis, IN. A total of 14 pre-surveys were collected, while 10 post-surveys were collected. Analyses of the sur-veys show beneficial topics , while also indicating which topics should receive additional focus. Areas of the program identified as needing attention include recruitment, risk management, transportation issues, participant dropout rates, logistics of workshops, continued training of lay leaders, and stand-ardization of survey responses. Conclusion: The pilot study identified the importance and need for a self-management program for youth and young adults with chronic conditions. This program has the potential to improve health and self-management in the study population. Limitations of the program were addressed and will be improved for the next round of workshops

    Adenocarcinoma of the Ethmoid Sinus Presenting with Epiphora

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    Abstract: Low-grade non-intestinal type adenocarcinomas are rare tumors that arise from the surface epithelium of the sinonasal tract. They frequently involve the ethmoid sinus, the nasal cavity, and the maxillary sinus. These tumors present at a mean age range of 37-53 years with various non-specific symptoms including nasal obstruction and epistaxis. We report the first case of a low-grade non-intestinal type sinonasal-adenocarcinoma of the ethmoid sinus presenting with persistent unilateral epiphora. Case Presentation: A 67-year-old man presented with complaints of bloody tearing and right medial canthus swelling for several months. Examination of the area revealed a small bump beneath the skin which burst with a green mucopurulent discharge on gentle palpation. Computed tomography (CT) scans revealed a large growth in the ethmoid sinus invading into the right medial orbit and extending into the maxilla. Histopathology (H&E) demonstrated a cribriform pattern, moderately graded nuclei, and eosinophilia consistent with non-intestinal type sinonasal adenocarcinoma. The patient underwent orbital exenteration and large sinus resection. Discussion: Cancers of the paranasal sinuses are extremely uncommon and account for just 1% of all human cancers. Low-grade non-intestinal type adenocarcinoma is an extremely rare subtype that has only been reported a handful of times. Synonyms in the literature include terminal tubulus adenocarcinoma, sinonasal tubulopapillary low-grade adenocarcinoma, and sinonasal seromucinous adenocarcinoma. Microscopic analysis is key for differentiation of this tumor type from other similar sinonasal malignancies as well as for prognostication purposes. Histologically, non-ITAC is recognized by its trabecular, cribaform, or papillary growth pattern and the single layer of uniform columnar or cuboidal cells that line its glands. Pleomorphic nuclei and mitotic figures are rarely seen in this subtype. Immunohistochemically, non-ITAC is characterized by positive CK7 staining and/or negative CDX-2 and CK-20 staining. Differential diagnoses to consider include intestinal type adenocarcinoma (ITAC), acinic cell carcinoma, and oncocytic Schneiderian papilloma. ITAC is an aggressive malignancy that is differentiated from non-ITAC on the basis of its resemblance to the mucosa found in the small and large intestine, its high-grade histologic appearance, and cellular expression of CDX-2. Distinguishing the two tumors types is of crucial clinical importance given that low-grade non-ITAC has not, to date, displayed metastatic behavior while several instances of low-grade ITAC metastases have been reported. Rarely, non-intestinal type adenocarcinoma may be confused with oncocytic Schneiderian papillomas. However, the epithelium of oncocytic Schneiderian papillomas are multilayered and lack glandular lumina. The presenting clinical symptoms of non-ITAC vary, however the most common reported symptoms are nasal obstruction and epistaxis. In our case, the patient presented with persistent unilateral epiphora which has not, to date, been reported in association with this tumor subtype. The mainstay in treatment of low-grade non-ITAC includes surgery followed by radiation therapy. Overall, the prognosis of patients with non-ITAC is good and rarely does death occur due to the disease.https://scholarlycommons.henryford.com/merf2020caserpt/1125/thumbnail.jp
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