296 research outputs found

    Molecular Carbon Chains and Rings in TMC-1

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    We present mapping results in several rotational transitions of HC3N, C6H, both cyclic and linear C3H2 and C3H, towards the cyanopolyyne peak of the filamentary dense cloud TMC-1 using the IRAM 30m and MPIfR 100m telescopes. The spatial distribution of the cumulene carbon chain propadienylidene H2C3 (hereafter l-C3H2) is found to deviate significantly from the distributions of the cyclic isomer c-C3H2, HC3N, and C6H which in turn look very similar. The cyclic over linear abundance ratio of C3H2 increases by a factor of 3 across the filament, with a value of 28 at the cyanopolyyne peak. This abundance ratio is an order of magnitude larger than the range (3 to 5) we observed in the diffuse interstellar medium. The cyclic over linear abundance ratio of C3H also varies by ~2.5 in TMC-1, reaching a maximum value (13) close to the cyanopolyyne peak. These behaviors might be related to competitive processes between ion-neutral and neutral-neutral reactions for cyclic and linear species.Comment: Accepted for publication in The Astrophysical Journal, part I. 24 pages, including 4 tables, 7 figures, and figure caption

    Evolution of an elliptical bubble in an accelerating extensional flow

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    Mathematical models that describe the dynamical behavior of a thin gas bubble embedded in a glass fiber during a fiber drawing process have been discussed and analyzed. The starting point for the mathematical modeling was the equations presented in [1] for a glass fiber with a hole undergoing extensional flow. These equations were reconsidered here with the additional reduction that the hole, i.e. the gas bubble, was thin as compared to the radius of the fiber and of finite extent. The primary model considered was one in which the mass of the gas inside the bubble was fixed. This fixed-mass model involved equations for the axial velocity and fiber radius, and equations for the radius of the bubble and the gas pressure inside the bubble. The model equations assumed that the temperature of the furnace of the drawing tower was known. The governing equations of the bubble are hyperbolic and predict that the bubble cannot extend beyond the limiting characteristics specified by the ends of the initial bubble shape. An analysis of pinch-off was performed, and it was found that pinch-off can occur, depending on the parameters of the model, due to surface tension when the bubble radius is small. In order to determine the evolution of a bubble, a numerical method of solution was presented. The method was used to study the evolution of two different initial bubble shapes, one convex and the other non-convex. Both initial bubble shapes had fore-aft symmetry, and it was found that the bubbles stretched and elongated severely during the drawing process. For the convex shape, fore-aft symmetry was lost in the middle of the drawing process, but the symmetry was re-gained by the end of the drawing tower. A small amount of pinch-off was observed at each end for this case, so that the final bubble length was slightly shorter than its theoretical maximum length. For the non-convex initial shape, pinch-off occurred in the middle of the bubble resulting in two bubbles by the end of the fiber draw. The two bubbles had different final pressures and did not have fore-aft symmetry. An extension of the fixed-mass model was considered in which the gas in the bubble was allowed to diffuse into the surrounding glass. The governing equations for this leaky-mass model were developed and manipulated into a form suitable for a numerical treatment

    Kartlegging av dagens rutiner for informasjonsutveksling ved utskrivning av pasienter som trenger kommunale helse- og omsorgstjenester

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    Masteroppgave i helse- og sosialinformatikk HSI500 2012 – Universitetet i Agder, GrimstadMasterprosjektet er gjennomført i samarbeid med Sørlandet sykehus HF. Prosjektet omfatter en kartlegging av dagens rutiner for informasjonsutveksling ved utskrivning av pasienter som trenger kommunale helse- og omsorgstjenester. I dag preges samarbeidet mellom sykehuset og den kommunale helse- og omsorgtjenesten av samhandlingsreformen. Intensjonen med samhandlingsreformen er at den skal føre til kortere liggetid for pasienter i sykehus, samt at kommunen skal overta pasientene tidligere i behandlingsforløpet. Dette medfører en enorm omstilling for begge parter som vil kreve bedre samhandling, økt kompetanse, klare retningslinjer og endringer i organisasjonene. Prosjektet bygger på intervjuer hvor informantene er relevante mennesker i helsetjenesten. Det er utført 11 kvalitative intervju av sykepleiere ansatt ved Sørlandet sykehus HF. Informantene har ulik alder og bakgrunn som sykepleiere. Målet med undersøkelsen er å kartlegge dagens utskrivningsrutiner samt å finne kritiske suksessfaktorer som kan være avgjørende ved implementeringen av et IS- system. I denne sammenhengen er IS- systemet som skal innføres elektroniske pleie- og omsorgsmeldinger. Datasamlingen foregikk over to uker, deretter ble det gjennomført transkribering og analyse av funn. I tilegg er det lest litteratur, faglige artikler og rapporter på det aktuelle tema. Gjennom intervjuene kom det frem beskrivelser av hvordan utskrivningen av pasienter fra SSHF til den kommunale helse- og omsorgstjenesten foregår. Det kom også frem utfordringer, og positive og negative erfaringer som er knyttet til utskrivning av disse pasientene. Funnene viser at rutiner i forhold til utskrivning varierer fra avdeling til avdeling, og at retningslinjene sykehuset har for utskrivning av pasienter som trenger kommunale pleie- omsorgs- og rehabiliteringstjenester ikke blir fulgt. Mange av sykepleierne kjenner heller ikke til retningslinjene som gjelder på deres arbeidsplass. Det er også, ved hjelp av litteraturen, identifisert flere suksessfaktorer som bør vektlegges ved implementering av elektroniske PLO-meldinger

    Reading performance with various lamps in age-related macular degeneration

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    The purpose of this study was to determine if there was an objective difference in reading between four commonly available lamps, of varying spectral radiance, for 13 subjects with age-related maculopathy (ARM) or non-exudative age-related macular degeneration (AMD) - logMAR visual acuity between 0.04 and 0.68. At a constant illuminance of 2000 lux, there was no interaction between ARM and AMD subgroups and no statistically significant difference between the lamps: standard (clear envelope) incandescent, daylight simulation (blue tint envelope) incandescent, compact fluorescent and halogen incandescent, for any reading outcome measure (threshold print size p = 0.67, critical print size p = 0.74, acuity reserve p = 0.84 and mean reading rate p = 0.78). For lamps typically used in low-vision rehabilitation, a clinically significant effect of spectral radiance on reading for people with ARM or non-exudative AMD is unlikely. © 2007 The College of Optometrists

    Kocuria kristinae infection associated with acute cholecystitis

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    BACKGROUND: Kocuria, previously classified into the genus of Micrococcus, is commonly found on human skin. Two species, K. rosea and K. kristinae, are etiologically associated with catheter-related bacteremia. CASE PRESENTATION: We describe the first case of K. kristinae infection associated with acute cholecystitis. The microorganism was isolated from the bile of a 56-year old Chinese man who underwent laparoscopic cholecystectomy. He developed post-operative fever that resolved readily after levofloxacin treatment. CONCLUSION: Our report of K. kristinae infection associated with acute cholecystitis expands the clinical spectrum of infections caused by this group of bacteria. With increasing number of recent reports describing the association between Kocuria spp. and infectious diseases, the significance of their isolation from clinical specimens cannot be underestimated. A complete picture of infections related to Kocuria spp. will have to await the documentation of more clinical cases

    An interlaboratory study of TEX86 and BIT analysis of sediments, extracts and standard mixtures.

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    Two commonly used proxies based on the distribution of glycerol dialkyl glycerol tetraethers (GDGTs) are the TEX86 (TetraEther indeX of 86 carbon atoms) paleothermometer for sea surface temperature reconstructions and the BIT (Branched Isoprenoid Tetraether) index for reconstructing soil organic matter input to the ocean. An initial round-robin study of two sediment extracts, in which 15 laboratories participated, showed relatively consistent TEX86 values (reproducibility ±3-4°C when translated to temperature) but a large spread in BIT measurements (reproducibility ±0.41 on a scale of 0-1). Here we report results of a second round-robin study with 35 laboratories in which three sediments, one sediment extract, and two mixtures of pure, isolated GDGTs were analyzed. The results for TEX86 and BIT index showed improvement compared to the previous round-robin study. The reproducibility, indicating interlaboratory variation, of TEX86 values ranged from 1.3 to 3.0°C when translated to temperature. These results are similar to those of other temperature proxies used in paleoceanography. Comparison of the results obtained from one of the three sediments showed that TEX86 and BIT indices are not significantly affected by interlaboratory differences in sediment extraction techniques. BIT values of the sediments and extracts were at the extremes of the index with values close to 0 or 1, and showed good reproducibility (ranging from 0.013 to 0.042). However, the measured BIT values for the two GDGT mixtures, with known molar ratios of crenarchaeol and branched GDGTs, had intermediate BIT values and showed poor reproducibility and a large overestimation of the "true" (i.e., molar-based) BIT index. The latter is likely due to, among other factors, the higher mass spectrometric response of branched GDGTs compared to crenarchaeol, which also varies among mass spectrometers. Correction for this different mass spectrometric response showed a considerable improvement in the reproducibility of BIT index measurements among laboratories, as well as a substantially improved estimation of molar-based BIT values. This suggests that standard mixtures should be used in order to obtain consistent, and molar-based, BIT values
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