24 research outputs found

    Cold atoms in space: community workshop summary and proposed road-map

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    We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.publishedVersio

    Risk factors and outcomes associated with recurrent autoimmune hepatitis following liver transplantation

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    Background & Aims: Autoimmune hepatitis can recur after liver transplantation (LT), though the impact of recurrence on patient and graft survival has not been well characterized. We evaluated a large, international, multicenter cohort to identify the probability and risk factors associated with recurrent AIH and the association between recurrent disease and patient and graft survival.Methods: We included 736 patients (77% female, mean age 42 +/- 1 years) with AIH who underwent LT from January 1987 through June 2020, among 33 centers in North America, South America, Europe and Asia. Clinical data before and after LT, biochemical data within the first 12 months after LT, and immunosuppression after LT were analyzed to identify patients at higher risk of AIH recurrence based on histological diagnosis.Results: AIH recurred in 20% of patients after 5 years and 31% after 10 years. Age at LT <= 42 years (hazard ratio [HR] 3.15; 95% CI 1.22-8.16; p = 0.02), use of mycophenolate mofetil post-LT (HR 3.06; 95% CI 1.39-6.73; p = 0.005), donor and recipient sex mismatch (HR 2.57; 95% CI 1.39-4.76; p = 0.003) and high IgG pre-LT (HR 1.04; 95% CI 1.01-1.06; p = 0.004) were associated with higher risk of AIH recurrence after adjusting for other confounders. In multivariate Cox regression, recurrent AIH (as a time-dependent covariate) was significantly associated with graft loss (HR 10.79, 95% CI 5.37-21.66, p <0.001) and death (HR 2.53, 95% CI 1.48-4.33, p = 0.001).Conclusion: Recurrence of AIH following transplant is frequent and is associated with younger age at LT, use of mycophenolate mofetil post-LT, sex mismatch and high IgG pre-LT. We demonstrate an association between disease recurrence and impaired graft and overall survival in patients with AIH, highlighting the importance of ongoing efforts to better characterize, prevent and treat recurrent AIH.Lay summary: Recurrent autoimmune hepatitis following liver transplant is frequent and is associated with some recipient features and the type of immunosuppressive medications use. Recurrent autoimmune hepatitis negatively affects outcomes after liver transplantation. Thus, improved measures are required to prevent and treat this condition. (C) 2022 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.Cellular mechanisms in basic and clinical gastroenterology and hepatolog

    Investigation of the effect of canola methyl ester on cyclic variation using wavelet analysis method

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    Diesel engines are the most commonly used internal combustion engine in transportation, power generation, and other industries. Combustion in the diesel engines takes place at high temperatures due to the high compression ratio, and therefore high energy is obtained when diesel fuel is used. But the most commonly used alternative fuel diesel engines is biodiesel today. The market share of biodiesel is on the rise because of the increasing damage of diesel and decreasing oil reserves to the environment. In this study, cyclic variation that occurred when canola biodiesel (canola methyl ester) that is produced by transesterification method was used as diesel fuel was investigated. Three different biodiesel ratios, B20, B50, and B100 were used in the study. In interpretation cyclic variations wavelet analysis method is used and all results are compared with diesel fuel. It is concluded that the use of biodiesel in diesel engines has positive effect on cyclic variation and this effect increases with the increasing ratio of biodiesel in the mixture. © Springer International Publishing Switzerland 2016

    Single solid source precursor route to the synthesis of MOCVD Cu-Cd-S thin films

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    Bis-(morpholinodithiato-s,s')-Cu-Cd was synthesized from appropriate reagents as a single solid source precursor and characterized using particle induced x-ray emission (PIXE), Fourier transform infrared (FTIR) spectroscopy and differential thermal analysis (DTA). Cu-Cd-S thin films were deposited on sodalime glass substrate using MOCVD technique at temperatures in the range 360 °C–450 °C. The films were further characterized using Rutherford backscattering spectroscopy (RBS), x-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy and four-point probe technique. PIXE revealed that the synthesized precursor contained the expected elements which led to the successful deposition of the Cu-Cd-S thin films. FTIR ascertained that the organic ligand actually attached to the metals. DTA analysis showed that the synthesized precursor was thermally stable and could pyrolyzed around 300 and 500 °C. RBS of the deposited films showed that the stoichiometry and the thickness depended on deposition temperature. XRD analysis revealed that the films deposited at 360 and 380 °C are amorphous while those deposited at 400 °C to 450 °C showed peaks, which supported the possible co-existence of CuS and CdS as Cu-Cd-S, with an improvement in the crystallinity as substrate temperature increased. SEM showed that the films are uniform and crack-free, in which the morphology strongly depended on substrate temperature. Optical analysis revealed that the films have high absorbance in the UV region and high transmittance in the visible and near infrared region, in which direct band gap energy of 2.36 to 2.14 eV was obtained as deposition temperature increased. Other optical parameters such as Urbach energy, refractive index, extinction coefficient, dielectric constant also increased as the deposition temperature increased. Electrical analysis showed that resistivity is temperature dependent as it reduced as deposition temperature increased.http://iopscience.iop.org/journal/2053-15912020-09-13hj2020Physic

    Ocorrência e abundância de Rynchops niger Linnaeus, no litoral de Santa Catarina, Brasil Occurrence and abundance of Rynchops niger Linnaeus in the coast of Santa Catarina, Brazil

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    O talha-mar Rynchops niger Linnaeus, 1758 habita os grandes rios, lagos e regiões costeiras durante as migrações, na América do Sul e do Norte. Esse trabalho tem por objetivo disponibilizar informações básicas sobre a ocorrência e abundância de talha-mar no litoral de Santa Catarina. Durante o período de abril/2002 a maio/2003 foram realizados censos sazonais (trimestrais) e mensais em Itajaí, com auxílio de binóculos 10 x 50. O talha-mar é mais freqüente no aterro da Baía Sul (Florianópolis), no verão e outono, na primavera-verão em São José e Tijucas e no outono-inverno no estuário do Saco da Fazenda (Itajaí). Neste estuário, a população apresentou flutuações acentuadas ao longo do ano, com as maiores abundâncias ocorrendo em agosto/2001, janeiro/2002 e março/2003.<br>The black skimmer inhabits the great rivers, lakes and coastal areas during the migrations, in South and North America. This work aims to make available basic information about the occurrence and abundance of the black skimmer in the coast of Santa Catarina. From April/2002 to May/2003 seasonal censuses were accomplished, and monthly in Itajaí, with aid of binoculars 10 x 50. The black skimmer is more frequent in the embankment of the South Bay (Florianópolis), in the summer and autumn, in the spring-summer in São José and Tijucas and in the autumn-winter in the estuary of the Saco da Fazenda (Itajaí). In this estuary, the population presented accentuated flotation along the year, with the largest abundances happening in August/2001, January/2002 and March/2003

    Rapid Response to Treatment of Autoimmune Hepatitis Associated With Remission at 6 and 12 Months

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    Contains fulltext : 219998.pdf (Publisher’s version ) (Closed access)BACKGROUND & AIMS: Changes in serum levels of transaminases immediately after initiation of treatment for autoimmune hepatitis (AIH) might be associated with biochemical markers of remission and liver-related events. We assessed the outcomes of patients with vs without rapid response to treatment of AIH in a large international cohort. METHODS: We performed a retrospective cohort study, collecting data from 2 independent cohorts of adults with AIH from 12 centers in 7 countries in Europe. We collected information on patient demographics; serologic, histologic, and biochemical analyses; and treatment. We used a receiver operating characteristic curve and Youden index to calculate the optimal percentage decrease in level of aspartate aminotransferase (AST) after 8 weeks of treatment that associated with normalization of transaminase levels after 26 weeks of treatment with predniso(lo)ne (primary outcome) in the first (discovery) cohort (n = 370). We evaluated the results in the second (validation) cohort (n = 370). Secondary outcomes were liver-related death or transplantation. We performed univariate and multivariable logistic and Cox regression with correction for confounders. RESULTS: A significant decrease in level of AST after 8 weeks of treatment was significantly associated with normalization of transaminase levels at 26 and 52 weeks (P < .001); a decrease of more than 80% in level of AST was associated with optimal normalization. In both cohorts, rapid responders (≥80% decrease in level of AST after 8 weeks) were more likely to achieve normalization of transaminases at 26 and 52 weeks when compared to non-rapid responders. Rapid responders in the discovery cohort had lower risk of liver-related death or transplantation (adjusted hazard ratio 0.18; 95% CI 0.05-0.63; P = .007), although this was not confirmed in the validation cohort. Results from measurement of alanine aminotransferase did not differ significantly from those of AST for the primary outcome. Slow responders (without normalization of transaminases after 1 year) had the highest risk of liver transplantation or liver-related death. CONCLUSIONS: In a retrospective study of patients with AIH, we found that a rapid response to treatment, based on level of AST after 8 weeks, associates with normalization of transaminase levels in the following year. Patients with a rapid response also have a lower risk of liver-related death or transplantation than patients without this rapid response
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