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The electric capacitance tomography (ECT) technique has been widely used in phase distribution reconstruction, while the practical application raised nonideal noise and other errors for cryogenic conditions, requiring a more accurate algorithm. This paper develops a new image reconstruction algorithm for ECT by coupling the traditional Landweber algorithm with the least square support vector regression (LSSVR) for cryogenic fluids. The performance of the algorithm is quantitatively evaluated by comparing the inversion images with the experimental results for both the room temperature working medium with the dielectric constant ratio close to cryogenic fluid and the cryogenic fluid of liquid nitrogen/nitrogen vapor (LN2-VN2). The inversion images based on the conventional LBP and Landweber algorithms are also presented for comparison. The benefits and drawbacks of the developed algorithms are revealed and discussed, according to the results. It is demonstrated that the correlated coefficients of the images based on the developed algorithm reach more than 0.88 and a maximum of 0.975. In addition, the minimum void fraction error of the algorithm is reduced to 0.534%, which indicates the significant optimization of the LSSVR coupled method over the Landweber algorithm. [ABSTRACT FROM AUTHOR]

More than half of adults with epilepsy undergoing resective epilepsy surgery achieve long-term seizure freedom and might consider withdrawing antiseizure medications (ASMs). We aimed to identify predictors of seizure recurrence after starting postoperative ASM withdrawal and develop and validate predictive models. We performed an international multicentre observational cohort study in nine tertiary epilepsy referral centres. We included 850 adults who started ASM withdrawal following resective epilepsy surgery and were free of seizures other than focal non-motor aware seizures before starting ASM withdrawal. We developed a model predicting recurrent seizures, other than focal non-motor aware seizures, using Cox proportional hazards regression in a derivation cohort (n = 231). Independent predictors of seizure recurrence, other than focal non-motor aware seizures, following the start of ASM withdrawal were focal non motor-aware seizures after surgery and before withdrawal (adjusted hazards ratio [aHR] 5.5, 95% confidence interval [CI] 2.7-11.1), history of focal to bilateral tonic-clonic seizures before surgery (aHR 1.6, 95% CI 0.9-2.8), time from surgery to the start of ASM withdrawal (aHR 0.9, 95% CI 0.8-0.9), and number of ASMs at time of surgery (aHR 1.2, 95% CI 0.9-1.6). Model discrimination showed a concordance statistic of 0.67 (95% CI 0.63-0.71) in the external validation cohorts (n = 500). A secondary model predicting recurrence of any seizures (including focal non-motor aware seizures) was developed and validated in a subgroup that did not have focal non-motor aware seizures before withdrawal (n = 639), showing a concordance statistic of 0.68 (95% CI 0.64-0.72). Calibration plots indicated high agreement of predicted and observed outcomes for both models. We show that simple algorithms, available as graphical nomograms and online tools (predictepilepsy.github.io), can provide probabilities of seizure outcomes after starting postoperative ASMs withdrawal. These multicentre-validated models may assist clinicians when discussing ASM withdrawal after surgery with their patients. [ABSTRACT FROM AUTHOR]

Objective Positive airway pressure (PAP) has been recognized as an effective therapeutic option for sleep-disordered breathing (SDB) in patients with heart failure (HF), and it can improve left ventricular function. Whether PAP can ameliorate serum brain natriuretic peptide (BNP) levels, a biomarker of HF, is controversial. The purpose of the present study was to quantitatively assess the efficacy of PAP on BNP in patients with HF and SDB. Methods A systematic search of PubMed, Embase, Web of Science and Cochrane library identified six randomized controlled trials (RCTs), in which PAP was compared with medical therapy, subtherapeutic PAP or different types of PAP. The data of BNP were extracted and pooled into meta-analysis using STATA 12.0. Results Totally 6 RCT studies (7 cohorts) with 222 patients were enrolled into analysis. The quality of each study was high and the heterogeneity (I.sup.2 = 58.1 %) was noted between studies. A significant reduction of BNP was observed after PAP treatment in patients with HF and SDB (SMD -0.517, 95 % CI -0.764 to -0.270, z = 4.11, p = 0.000). Conclusion Our meta-analysis of RCTs demonstrated that PAP elicits significant reduction of BNP in patients with HF and SDB., Author(s): Xiao-Bin Zhang[sup.1] , Ya-Ting Yuan[sup.1] , Yan-Ping Du[sup.1] , Xing-Tang Jiang[sup.1] , Hui-Qing Zeng[sup.1] Author Affiliations: (1) Department of Respiratory Medicine, Zhongshan Hospital, Xiamen University, No. 201, Hubin Nan [...]

Based on luminosity contributions, we develop aspectroscopic modelling method to derive atmospheric parameters of component stars in binary systems. The method is designed for those spectra of binaries that show double-lined features due to radial-velocity differences between the component stars. We first derive the orbital parameters and the stellar radii by solving the light and radial-velocity curves. The luminosity contributions in different phases can then be calculated. We construct a synthesised double-lined spectra model by superposing theoretical single-star spectra according to the luminosity contributions. Finally, we derive the atmospheric parameters of each component star using the model-fitting method. For multi-epoch double-lined spectra observed by the Large sky Area Multi-Object Spectroscopic Telescope (LAMOST) Medium Resolution Survey (R ~ 7500), our method gives robust results for detached eclipsing binary systems observed in different orbital phases. Furthermore, this method can also be applied to other spectroscopic data with different resolutions as long as the systems are detached eclipsing binaries with nearly spherical stars. [ABSTRACT FROM AUTHOR]