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This Letter reports the first extraction of individual antineutrino spectra from U235 and Pu239 fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×106 inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, U235 and Pu239, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4–6 MeV, a 7% (9%) excess of events is observed for the U235 (Pu239) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for U235 spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4–6 MeV, a maximal local discrepancy of 6.3σ is observed.

What Is Known and Objective. To reevaluate the benefits and risks of corticosteroid treatment in adult patients with septic shock. Methods. This study was performed based on PRISMA guidelines. Randomized controlled trials (RCTs) of corticosteroids versus placebo were retrieved from PubMed, MEDLINE, EMBASE, Web of Science, the Cochrane Central RCTs, and ClinicalTrials.gov from January 1980 to April 2018. We also conducted a trial sequential analysis to indicate the possibility of type I or II errors and calculate the information size. Grading of Recommendations, Assessment, Development and Evaluation approach (GRADE) was applying to assess the certainty of evidence at the primary outcome level. Results. Twenty-one RCTs were identified and analyzed. Patients treated with corticosteroid had a 7% reduction in relative risk in 28-day all-cause mortality compared to controls (RR 0.93, 95% CI 0.88 to 0.99). However, there were no significant differences for the intensive care unit (ICU) mortality (RR 0.97, 95% CI 0.86 to 1.09) or in-hospital mortality (RR 1.01, 95% CI 0.92 to 1.11). Corticosteroids shortened the length of ICU stay by 1.04 days (RR -1.04, 95% CI -1.72 to -0.36) and the length of hospital stay by 2.49 days (RR -2.49, 95% CI -4.96 to -0.02). Corticosteroids increased the risk of hyperglycemia (RR 1.11, 95% CI 1.06 to 1.16) but not gastroduodenal bleeding (RR 1.06, 95% CI 0.82 to 1.37) or superinfection (RR 1.04, 95% CI 0.94 to 1.15). However, some date on secondary outcomes were unavailable because they were not measured or not reported in the included studies which may cause a lack of power or selective outcome reporting. The information size was calculated at 10044 patients. Trial sequential analysis showed that the meta-analysis was conclusive and the risk of type 2 error was minimal. What Is New and Conclusion. Corticosteroids are likely to be effective in reducing 28-day mortality and attenuating septic shock without increasing the rate of life-threatening complications. TSA showed that the risk of type II error in this meta-analysis was minimal and the result was conclusive.