15 research outputs found

    Ceramic Paste for Patching High-Temperature Insulation

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    A ceramic paste that can be applied relatively easily, either by itself or in combination with one or more layer(s) of high-temperature ceramic fabrics, such as silicon carbide or zirconia, has been invented as a means of patching cracks or holes in the reinforced carbon-carbon forward surfaces of a space shuttle in orbit before returning to Earth. The paste or the paste/fabric combination could also be used to repair rocket-motor combustion chambers, and could be used on Earth to patch similar high-temperature structures. The specified chemical composition of the paste admits of a number of variations, and the exact proportions of its constituents are proprietary. In general, the paste consists of (1) silicon carbide, possibly with addition of (2) hafnium carbide, zirconium carbide, zirconium boride, silicon tetraboride, silicon hexaboride, or other metal carbides or oxides blended with (3) a silazane-based polymer. Because the paste is viscous and sticky at normal terrestrial and outer-space ambient temperatures, high-temperature ceramic fabrics such as silicon carbide or zirconia fabric impregnated with the paste (or the paste alone) sticks to the damaged surface to which it is applied. Once the patch has been applied, it is smoothed to minimize edge steps as required [forward-facing edge steps must be < or equal to 0.030 in. (< or equal to 0.76 mm) in the original intended space-shuttle application]. The patch is then heated to a curing temperature thereby converting it from a flexible material to a hard, tough material. The curing temperature is 375 to 450 F (approx.190 to 230 C). In torch tests and arc-jet tests, the cured paste was found to be capable of withstanding a temperature of 3,500 F (approx. 1,900 C) for 15 minutes. As such, the material appears to satisfy the requirement, in the original space-shuttle application, to withstand re-entry temperatures of approx.3,000 F (approx. 1,600 C)

    Evaluation of model‐simulated upper troposphere humidity using 6.7 μm satellite observations

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    Use of mesoscale models to simulate details of upper tropospheric relative humidity (UTRH) fields represents an important step toward understanding the evolution of small‐scale water vapor structures that are responsible for cirrus growth and dissipation. Because mesoscale model UTRH simulations require initialization and verification and since radiosonde measurements of relative humidity are unreliable in the upper troposphere, we use GOES 6.7 μm water vapor observations to validate the Pennsylvania State University/National Center for Atmospheric Research nonhydrostatic mesoscale model (MM5) simulations of UTRH. To accomplish this task, MM5 temperature and moisture profiles are used in a forward calculation of the clear‐sky 6.7 μm brightness temperature (T6.7), which is converted into UTRH. A statistical analysis is done to evaluate MM5 simulations of T6.7 and UTRH against the GOES 7 observations. For the simulations, an average correlation coefficient of 0.80 was found with a dry bias of 1.6 K. In terms of UTRH, the average correlation coefficient was 0.65 with a dry bias of 3.3%. We also found that MM5 fails to simulate accurately extrema in the UTRH field

    Sincerely James: Reconsidering Frederick Francis’s Proposed Health Wish Formula

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    This article interacts with Frederick Francis’s well-known suggestion that Jas 5 contains a health wish formula. Based on more recent findings of epistolography, this article argues that the references to healing in Jas 5 contrast sharply with the first-century CE health wish formula(s). In addition to current research on Hellenistic epistolography, this article offers three further pieces of evidence which suggest that the letter of James does not conclude with a health wish formula, but rather with a promise of restoration from spiritual sickness

    Elinsiirron saaneen nuoren siirtyminen lasten ja nuorten hoitotyöstä aikuisten terveyspalveluiden käyttäjäksi

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    Opinnäytetyömme tarkoituksena on kuvata saumaton, hoitoon sitoutumista tukeva hoitopolku nuoren elinsiirtopotilaan siirtyessä lasten ja nuorten hoitotyöstä aikuisten terveyspalvelujen käyttäjäksi. Työmme on osa lasten ja nuorten hoitotyön osaamisen tulevaisuuden hanketta. Hankkeen tarkoituksena on uusien toimintakäytäntöjen luominen, verkostomaisen työskentelyn vahvistaminen, sekä saumattomien hoitopolkujen kehittäminen. Hankkeessa yhteistyökumppaneina ovat HYKS Naisten- ja lastentautien tulosyksikkö, Metropolia ammattikorkeakoulun Hoitotyön koulutusohjelma ja Tampereen yliopiston Hoitotieteen laitos. Työssämme keskitymme potilaan siirtymävaiheen solmukohtiin, kuvaamme nykyisen hoitopolun ja pyrimme löytämään näkökulmia sekä toimintamalleja, jotka antaisivat nuorelle, hänen perheelleen sekä hoitoyksikölle valmiuksia siirtymisprosessin vaiheisiin. Työssämme keskitymme nuorten kehittymishaasteisiin ja pyrimme kartoittamaan nuorten hoitomyönteisyyttä ja vastaanottavaisuutta edistäviä keinoja ja välineitä. Opinnäytetyömme aihe on uusi hoitotieteellisen tutkimuksen kohde ja löytämämme materiaali on luonteeltaan täsmällistä, tuoretta ja vastaa hyvin työmme edistymisen vaateisiin. Käytimme työssämme kvantitatiivista tutkimusmenetelmää. Tutkimustyön tarve sekä prosessin kehittäminen potilaan tarpeita vastaavaksi tällä hoitotyön saralla on erittäin tärkeää. Kansainvälisesti siirtymisessä koetaan haastavimmaksi prosessin alkamisen äkillisyys, riittämätön tiedonkulku lasten ja aikuisten puolen välillä ja tätä kautta hoidon jatkuvuuden kankeus. Toisin sanoen siirtymiseen valmistavien toimintojen aikaistaminen, kirjallinen informaatio ja sujuvampi yhteistyö palveluiden tarjoajien välillä, ovat suurimmat kehittymishaasteet

    Predictors of Enteral Autonomy in Children with Intestinal Failure: A Multicenter Cohort Study

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    ObjectivesIn a large cohort of children with intestinal failure (IF), we sought to determine the cumulative incidence of achieving enteral autonomy and identify patient and institutional characteristics associated with enteral autonomy.Study designA multicenter, retrospective cohort analysis from the Pediatric Intestinal Failure Consortium was performed. IF was defined as severe congenital or acquired gastrointestinal diseases during infancy with dependence on parenteral nutrition (PN) &gt;60 days. Enteral autonomy was defined as PN discontinuation &gt;3 months.ResultsA total of 272 infants were followed for a median (IQR) of 33.5 (16.2-51.5) months. Enteral autonomy was achieved in 118 (43%); 36 (13%) remained PN dependent and 118 (43%) patients died or underwent transplantation. Multivariable analysis identified necrotizing enterocolitis (NEC; OR 2.42, 95% CI 1.33-4.47), care at an IF site without an associated intestinal transplantation program (OR 2.73, 95% CI 1.56-4.78), and an intact ileocecal valve (OR 2.80, 95% CI 1.63-4.83) as independent risk factors for enteral autonomy. A second model (n = 144) that included only patients with intraoperatively measured residual small bowel length found NEC (OR 3.44, 95% CI 1.36-8.71), care at a nonintestinal transplantation center (OR 6.56, 95% CI 2.53-16.98), and residual small bowel length (OR 1.04 cm, 95% CI 1.02-1.06 cm) to be independently associated with enteral autonomy.ConclusionsA substantial proportion of infants with IF can achieve enteral autonomy. Underlying NEC, preserved ileocecal valve, and longer bowel length are associated with achieving enteral autonomy. It is likely that variations in institutional practices and referral patterns also affect outcomes in children with IF

    Is Obama's 2014 Greenhouse Gas Reduction Plan Symbolic? The Creation of the US EPA and a Reliance on the States

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