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1.
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2.
  • Carter, Aarynn L., et al. (author)
  • A benchmark JWST near-infrared spectrum for the exoplanet WASP-39 b
  • 2024
  • In: Nature Astronomy. - 2397-3366. ; In Press
  • Journal article (peer-reviewed)abstract
    • A combined analysis of datasets across four JWST instrument modes provides a benchmark transmission spectrum for the Saturn-mass WASP-39 b. The broad wavelength range and high resolution constrain orbital and stellar parameters to below 1%.
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4.
  • Marti-Gallostra, M., et al. (author)
  • The role of a defunctioning stoma for colonic and perianal Crohns disease in the biological era
  • 2017
  • In: Scandinavian Journal of Gastroenterology. - : TAYLOR & FRANCIS LTD. - 0036-5521 .- 1502-7708. ; 52:3, s. 251-256
  • Journal article (peer-reviewed)abstract
    • Objective: A defunctioning stoma is a therapeutic option for colonic or perianal Crohns disease. In the pre-biologic era the response rate to defunctioning in our unit was high (86%), but intestinal continuity was only restored in 11-20%. Few data exist on the outcome of defunctioning since the widespread introduction of biologicals. Material and methods: All patients undergoing a defunctioning stoma for colonic/perianal Crohns disease since 2003-2011 were identified from a prospective database. Indications for surgery, medical therapy, response to defunctioning and long-term clinical outcome were recorded. Successful restoration of continuity was defined as no stoma at last follow up. Results: Seventy-six patients were defunctioned (57 with biologicals) and at last follow up, 20 (27%) had continuity restored. Early clinical response rate (amp;lt;3 months) was 15/76 (20%) and overall response 31/76 (41%). Complex anal fistulae/stenosis were associated with a very low chance of restoring continuity (10% and 0%, respectively), while colitis was associated with a higher chance of restoring continuity (48%). Endoscopic or histological improvement in colitis after defunctioning was associated with a higher rate of restoring continuity (10/16, 63%) compared to no such improvement (4/15, 27%, p=0.05). Those failing biologics had similar chance of restoration as those not receiving biologics, 15/57 (26%) and 5/19 (26%), respectively. Conclusion: Overall response to colonic defunctioning was 41%. Successful restoration of continuity occurred in 27%, but 48% in the absence of perianal disease. Response is appreciably less in the pre-biologic era, so patient and physician expectations need to be managed appropriately.
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5.
  • Bell, Taylor, et al. (author)
  • Nightside clouds and disequilibrium chemistry on the hot Jupiter WASP-43b
  • 2024
  • In: Nature Astronomy. - 2397-3366. ; In Press
  • Journal article (peer-reviewed)abstract
    • Hot Jupiters are among the best-studied exoplanets, but it is still poorly understood how their chemical composition and cloud properties vary with longitude. Theoretical models predict that clouds may condense on the nightside and that molecular abundances can be driven out of equilibrium by zonal winds. Here we report a phase-resolved emission spectrum of the hot Jupiter WASP-43b measured from 5 μm to 12 μm with the JWST’s Mid-Infrared Instrument. The spectra reveal a large day–night temperature contrast (with average brightness temperatures of 1,524 ± 35 K and 863 ± 23 K, respectively) and evidence for water absorption at all orbital phases. Comparisons with three-dimensional atmospheric models show that both the phase-curve shape and emission spectra strongly suggest the presence of nightside clouds that become optically thick to thermal emission at pressures greater than ~100 mbar. The dayside is consistent with a cloudless atmosphere above the mid-infrared photosphere. Contrary to expectations from equilibrium chemistry but consistent with disequilibrium kinetics models, methane is not detected on the nightside (2σ upper limit of 1–6 ppm, depending on model assumptions). Our results provide strong evidence that the atmosphere of WASP-43b is shaped by disequilibrium processes and provide new insights into the properties of the planet’s nightside clouds. However, the remaining discrepancies between our observations and our predictive atmospheric models emphasize the importance of further exploring the effects of clouds and disequilibrium chemistry in numerical models.
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6.
  • Cesarini, Monica, et al. (author)
  • Predicting the Individual Risk of Acute Severe Colitis at Diagnosis
  • 2017
  • In: Journal of Crohn's & Colitis. - : OXFORD UNIV PRESS. - 1873-9946 .- 1876-4479. ; 11:3, s. 335-341
  • Journal article (peer-reviewed)abstract
    • Background and Aims: Acute severe colitis [ASC] is associated with major morbidity. We aimed to develop and externally validate an index that predicted ASC within 3 years of diagnosis. Methods: The development cohort included patients aged 16-89 years, diagnosed with ulcerative colitis [UC] in Oxford and followed for 3 years. Primary outcome was hospitalization for ASC, excluding patients admitted within 1 month of diagnosis. Multivariable logistic regression examined the adjusted association of seven risk factors with ASC. Backwards elimination produced a parsimonious model that was simplified to create an easy-to-use index. External validation occurred in separate cohorts from Cambridge, UK, and Uppsala, Sweden. Results: The development cohort [Oxford] included 34/111 patients who developed ASC within a median 14 months [range 1-29]. The final model applied the sum of 1 point each for extensive disease, C-reactive protein [CRP] >10 mg/l, or haemoglobin < 12 g/dl F or < 14 g/dl M at diagnosis, to give a score from 0/3 to 3/3. This predicted a 70% risk of developing ASC within 3 years [score 3/3]. Validation cohorts included different proportions with ASC [Cambridge = 25/96; Uppsala = 18/298]. Of those scoring 3/3 at diagnosis, 18/18 [Cambridge] and 12/13 [Uppsala] subsequently developed ASC. Discriminant ability [c-index, where 1.0 = perfect discrimination] was 0.81 [Oxford], 0.95 [Cambridge], 0.97 [Uppsala]. Internal validation using bootstrapping showed good calibration, with similar predicted risk across all cohorts. A nomogram predicted individual risk. Conclusions: An index applied at diagnosis reliably predicts the risk of ASC within 3 years in different populations. Patients with a score 3/3 at diagnosis may merit early immunomodulator therapy.
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7.
  • Leipold, Sina, et al. (author)
  • Lessons, narratives, and research directions for a sustainable circular economy
  • 2023
  • In: Journal of Industrial Ecology. - : Wiley. - 1088-1980 .- 1530-9290. ; 27:1, s. 6-18
  • Journal article (peer-reviewed)abstract
    • The current enthusiasm for the circular economy (CE) offers a unique opportunity to advance the impact of research on sustainability transitions. Diverse interpretations of CE by scholars, however, produce partly opposing assessments of its potential benefits, which can hinder progress. Here, we synthesize policy-relevant lessons and research directions for a sustainable CE and identify three narratives—optimist, reformist, and skeptical—that underpin the ambiguity in CE assessments. Based on 54 key CE scholars’ insights, we identify three research needs: the articulation and discussion of ontologically distinct CE narratives; bridging of technical, managerial, socio-economic, environmental, and political CE perspectives; and critical assessment of opportunities and limits of CE science–policy interactions. Our findings offer practical guidance for scholars to engage reflexively with the rapid expansion of CE knowledge, identify and pursue high-impact research directions, and communicate more effectively with practitioners and policymakers.
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8.
  • Powell, Diana, et al. (author)
  • Sulfur dioxide in the mid-infrared transmission spectrum of WASP-39b
  • 2024
  • In: Nature. - 0028-0836 .- 1476-4687. ; 626:8001, s. 979-983
  • Journal article (peer-reviewed)abstract
    • The recent inference of sulfur dioxide (SO2) in the atmosphere of the hot (approximately 1,100 K), Saturn-mass exoplanet WASP-39b from near-infrared JWST observations1–3 suggests that photochemistry is a key process in high-temperature exoplanet atmospheres4. This is because of the low (<1 ppb) abundance of SO2 under thermochemical equilibrium compared with that produced from the photochemistry of H2O and H2S (1–10 ppm)4–9. However, the SO2 inference was made from a single, small molecular feature in the transmission spectrum of WASP-39b at 4.05 μm and, therefore, the detection of other SO2 absorption bands at different wavelengths is needed to better constrain the SO2 abundance. Here we report the detection of SO2 spectral features at 7.7 and 8.5 μm in the 5–12-μm transmission spectrum of WASP-39b measured by the JWST Mid-Infrared Instrument (MIRI) Low Resolution Spectrometer (LRS)10. Our observations suggest an abundance of SO2 of 0.5–25 ppm (1σ range), consistent with previous findings4. As well as SO2, we find broad water-vapour absorption features, as well as an unexplained decrease in the transit depth at wavelengths longer than 10 μm. Fitting the spectrum with a grid of atmospheric forward models, we derive an atmospheric heavy-element content (metallicity) for WASP-39b of approximately 7.1–8.0 times solar and demonstrate that photochemistry shapes the spectra of WASP-39b across a broad wavelength range.
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9.
  • Rijal, Suman, et al. (author)
  • Increasing failure of miltefosine in the treatment of Kala-azar in Nepal and the potential role of parasite drug resistance, reinfection, or noncompliance.
  • 2013
  • In: Clinical Infectious Diseases. - : Oxford University Press (OUP). - 1058-4838 .- 1537-6591. ; 56:11, s. 1530-8
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: Miltefosine (MIL), the only oral drug for visceral leishmaniasis (VL), is currently the first-line therapy in the VL elimination program of the Indian subcontinent. Given the paucity of anti-VL drugs and the looming threat of resistance, there is an obvious need for close monitoring of clinical efficacy of MIL.METHODS: In a cohort study of 120 VL patients treated with MIL in Nepal, we monitored the clinical outcomes up to 12 months after completion of therapy and explored the potential role of drug compliance, parasite drug resistance, and reinfection.RESULTS: The initial cure rate was 95.8% (95% confidence interval [CI], 92.2-99.4) and the relapse rate at 6 and 12 months was 10.8% (95% CI, 5.2-16.4) and 20.0% (95% CI, 12.8-27.2) , respectively. No significant clinical risk factors of relapse apart from age <12 years were found. Parasite fingerprints of pretreatment and relapse bone marrow isolates within 8 patients were similar, suggesting that clinical relapses were not due to reinfection with a new strain. The mean promastigote MIL susceptibility (50% inhibitory concentration) of isolates from definite cures was similar to that of relapses. Although more tolerant strains were observed, parasite resistance, as currently measured, is thus not likely involved in MIL treatment failure. Moreover, MIL blood levels at the end of treatment were similar in cured and relapsed patients.CONCLUSIONS: Relapse in one-fifth of the MIL-treated patients observed in our study is an alarming signal for the VL elimination campaign, urging for further review and cohort monitoring.
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10.
  • Sui, Xin, et al. (author)
  • Parallel clustered low-rank approximation of graphs and its application to link prediction
  • 2012
  • In: Proceedings of the International Workshop on Languages and Compilers for Parallel Computing. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783642376573 - 9783642376580 ; , s. 76-95
  • Conference paper (other academic/artistic)abstract
    • Social network analysis has become a major research area that has impact in diverse applications ranging from search engines to product recommendation systems. A major problem in implementing social network analysis algorithms is the sheer size of many social networks, for example, the Facebook graph has more than 900 million vertices and even small networks may have tens of millions of vertices. One solution to dealing with these large graphs is dimensionality reduction using spectral or SVD analysis of the adjacency matrix of the network, but these global techniques do not necessarily take into account local structures or clusters of the network that are critical in network analysis. A more promising approach is clustered low-rank approximation: instead of computing a global low-rank approximation, the adjacency matrix is first clustered, and then a low-rank approximation of each cluster (i.e., diagonal block) is computed. The resulting algorithm is challenging to parallelize not only because of the large size of the data sets in social network analysis, but also because it requires computing with very diverse data structures ranging from extremely sparse matrices to dense matrices. In this paper, we describe the first parallel implementation of a clustered low-rank approximation algorithm for large social network graphs, and use it to perform link prediction in parallel. Experimental results show that this implementation scales well on large distributed-memory machines; for example, on a Twitter graph with roughly 11 million vertices and 63 million edges, our implementation scales by a factor of 86 on 128 processes and takes less than 2300 seconds, while on a much larger Twitter graph with 41 million vertices and 1.2 billion edges, our implementation scales by a factor of 203 on 256 processes with a running time about 4800 seconds.
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