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Background: Requirements of blood transfusions rise rapidly in China. Improving the efficiency of blood donation could help maintaining sufficient blood supplement. We conducted a pilot research to investigate the reliability and safety of collecting more units of red blood cell by apheresis. Methods: Thirty‐two healthy male volunteers were randomized into two groups: red blood cell apheresis (RA) (n = 16) and whole blood (WB) donation (n = 16). RA group donated individualized RBC volumes by apheresis according to the volunteers' basal total blood volumes and haematocrit levels, WB group donated 400 mL whole blood. All volunteers were scheduled seven visit times in 8 weeks' study period. The cardiovascular functions were assessed by laboratory examinations, echocardiography and cardiopulmonary functional tests. All results were compared between groups at the same visit time and compared between visit 1(before donation) and other visit times within the same group. Results: The average donated RBC volume in RA group and in WB group was 627.25 ± 109.74 mL and 175.28 ± 8.85 mL, respectively(p < 0.05); the RBC, haemoglobin and haematocrit levels changed significantly between times and between groups (p < 0.05). Cardiac biomarker levels such as NT‐proBNP, hs‐TnT and CK‐MB did not change significantly between times or between groups (p > 0.05). The echocardiographic and cardiopulmonary results did not change significantly between times or between groups during the whole study period(p > 0.05). Conclusions: We provided an efficient and secure method for RBC apheresis. By harvesting more RBC volumes at one single‐time, the cardiovascular functions did not change significantly compared with traditional whole blood donation. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an adaptive neural tracking control approach for uncertain stochastic nonlinear time‐delay systems with input and output constraints. Firstly, the dynamic surface control (DSC) technique is incorporated into adaptive neural control framework to overcome the problem of ‘explosion of complexity’ in the control design. By employing a continuous differentiable asymmetric saturation model, the input constraint problem is solved. Secondly, the appropriate Lyapunov‐Krasovskii functional and the property of hyperbolic tangent functions are used to deal with the unknown time‐delay terms, RBF neural network is utilized to identify the unknown systems functions, and barrier Lyapunov functions (BLFs) are designed to avoid the violation of the output constraint. Finally, based on adaptive backstepping technique, an adaptive neural control method is proposed, and it decreases the number of learning parameters. Using Lyapunov stability theory, it is proved that the designed controller can ensure that all the signals in the closed‐loop system are 4‐Moment (or 2 Moment) semi‐globally uniformly ultimately bounded (SGUUB) and the tracking error converges to a small neighborhood of the origin. Two simulation examples are provided to further illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Aim: Chronic hepatitis B (CHB) patients with normal alanine aminotransferase (ALT) levels are not free from significant hepatic lesions. Recently, there has been an improved understanding of the clinical significance of quantitative hepatitis B core antibody levels (qAnti‐HBc) during CHB management. In this cross‐sectional study, we evaluated the utility of qAnti‐HBc in identifying significant liver inflammation in CHB patients. Methods: A total of 469 patients (training set, n = 363; validation set, n = 106) who underwent liver biopsy (LB) were included. The qAnti‐HBc levels were quantified and the relationship between histology and serum markers was systematically analyzed. Results: In the training set, qAnti‐HBc levels were found to have significant diagnostic value for moderate to severe liver inflammation (≥G2) in all patients (area under the receiver operating characteristic curve [AUROC] = 0.768; 95% confidence interval [CI], 0.721–0.810; P < 0.001) and in patients with normal or near‐normal ALT levels (AUROC = 0.767; 95% CI, 0.697–0.828; P < 0.001). Our novel index (AC index) for the identification of ≥G2 inflammation, which combined the qAnti‐HBc and ALT levels, significantly improved diagnostic performance (AUROC = 0.813; 95% CI, 0.768–0.852) compared to the use of ALT alone (AUROC = 0.779; 95% CI, 0.732–0.821) in all patients. In the validation set, the AC index showed an improved AUROC of 0.890 (95% CI, 0.814–0.942) and 0.867 (95% CI, 0.749–0.943) in all patients and patients with normal ALT levels, respectively. Conclusions: The qAnti‐HBc level predicts significant liver inflammation well, even in patients with normal or near‐normal ALT levels. Compared with the conventional ALT level, the AC index is a more reliable non‐invasive biomarker for significant liver inflammation in CHB patients. [ABSTRACT FROM AUTHOR]