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Iterative learning control (ILC) enables high performance for motion systems executing repetitive tasks. The robustness filter of ILC enhances the robustness w.r.t. model uncertainties and disturbances, but results in that the repetitive error cannot be eliminated. In this paper, a dual-loop ILC (DILC) approach is proposed for precision motion systems to explicitly address the design tradeoff of standard ILC between robustness and tracking performance. In the proposed DILC approach, the standard ILC is paralleled with an additional feedforward signal. When ILC converges, the additional feedforward signal is updated by the converged total feedforward signal, and then the ILC begins a new iteration. As a result, the non-zero asymptotic error caused by the robustness filter is eliminated by adding an iterative action over the feedforward signal onto ILC. Comparative simulation and experimental results confirm that, compared to ILC, the proposed DILC can significantly enhance the tracking performance without sacrifice of robustness w.r.t. model uncertainties and disturbances. Application to an ultraprecision wafer stage illustrates that the proposed DILC decreases the peak values of moving average and moving standard deviation of the tracking error by 52.7% and 43.9%, respectively.

Introduction: The introduction of antiviral therapy in chronic hepatitis B (CHB) infection depends on precise evaluation of hepatic lesions. Total serum bile acids (TSBAs) are highly sensitive in monitoring liver dysfunction. We evaluated the predictive role of TSBAs for hepatic lesions in CHB patients with borderline alanine aminotransferase (ALT) and high level of hepatitis B virus (HBV) DNA copies. Methodology: 328 CHB patients were enrolled, 241 were hepatitis B e antigen (HBeAg)-positive and 87 were HBeAg-negative. Patients were further divided into two entities according to inflammation/fibrosis evaluated by liver biopsy, low-grade (inflammation grade < 2 and fibrosis stage < 2) and high-grade (inflammation grade ≥ 2 or/and fibrosis stage ≥ 2) cohorts. TSBAs were compared with noninvasive tools including aspartate aminnotransferase (AST)-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) and red cell distribution width (RDW)-to-platelet ratio (RPR) to predict high-grade hepatic lesions in CHB subgroups. Results: TSBAs, APRI, FIB-4 and RPR were statistically different between low- and high-grade patients in HBeAg-positive cohort. Only TSBAs showed significant difference between low and high grade in HBeAg-negative patients. Similarly, APRI, FIB-4 and RPR were correlated with different division of inflammation/fibrosis only in HBeAg-positive while TSBAs were correlated with inflammation/fibrosis levels in both HBeAg-positive and HBeAg-negative groups. Of the four indicators, the receiver operating characteristic (ROC) curve analysis showed that TSBAs have the maximum AUC (area under the curve) in HBeAg-negative group but the minimum in HBeAg-positive cohort. Conclusions: TSBAs can be used for predicting antiviral therapy in CHB patients with HBeAg-negative, borderline ALT and high HBV DNA.

Metal oxides are promising (photo)electrocatalysts for sustainable energy technologies due to their good activity and abundant resources. Their applications such as photocatalytic water splitting predominantly involve aqueous inter- faces at electrochemical conditions, but in situ probing oxide-water interfaces is proven to be extremely challenging. Here, we present an electrochemical scanning tunneling microscopy (EC-STM) study on the rutile TiO2(110)-water interface, and by tuning surface redox chemistry with careful potential control we are able to obtain high quality images of interfacial structures with atomic details. It is interesting to find that the interfacial water exhibits an unexpected double-row pattern that has never been observed. This finding is confirmed by performing a large scale simulation of a stepped interface model enabled by machine learning accelerated molecular dynamics (MLMD) at ab initio accuracy. Furthermore, we show that this pattern is induced by the steps present on the surface, which can propagate across the terraces by interfacial hydrogen bonds. Our work demonstrates that by combining EC-STM and MLMD we can obtain new atomic details of interfacial structures that are valuable to understand the activity of oxides at realistic conditions.

Background Postoperative delirium (POD) is considered as a relatively common and serious problem after major abdominal surgery procedures. It is presumed to be preventable in most of cases. The purpose of this study was to develop and evaluate a POD prediction model for patients undergoing abdominal surgery. Methods From July 2019 to December 2019, patients underwent elective abdominal surgery in our hospital were retrospectively analyzed, and their demographics, pre-operative evaluation, intra-operative and anesthesiologic factors were recorded. Based on the results of the multivariate regression analyzes using P

Background: The dysregulation of lipid metabolism plays an important role in the pathogenesis of Alzheimer’s disease (AD). Liver-type fatty acid-binding protein (L-FABP, also known as FABP1) is critical for fatty acid transport and may be involved in AD. Objective: To investigate whether the FABP1 level is altered in patients with AD, and its associations with levels of amyloid-β (Aβ) and tau in the plasma and cerebrospinal fluid (CSF). Methods: A cross-sectional study was conducted in a Chinese cohort consisting of 39 cognitively normal controls and 47 patients with AD. The levels of FABP1 in plasma, and Aβ and tau in CSF, were measured by enzyme-linked immunosorbent assay (ELISA). A single-molecule array (SIMOA) was used to detect plasma Aβ levels. Results: The level of plasma FABP1 was significantly elevated in the AD group (p = 0.0109). Further analysis showed a positive correlation of FABP1 with CSF total tau (t-tau) and phosphorylated tau (p-tau) levels. Besides, plasma FABP1/Aβ42 (AUC = 0.6794, p = 0.0071) and FABP1/t-tau (AUC = 0.7168, p = 0.0011) showed fair diagnostic efficacy for AD. When combined with other common AD biomarkers including plasma Aβ42, Aβ40, and t-tau, both FABP1/Aβ42 and FABP1/t-tau showed better diagnostic efficacy than using these biomarkers alone. Among all AUC analyses, the combination of plasma FABP1/t-tau and Aβ42 had the highest diagnostic value (AUC = 0.8075, p

Background: The G protein-coupled receptor P2RY2 protein of the purinergic receptor family is involved in the pathogenesis of Alzheimer’s disease (AD). Naturally occurring antibodies against P2RY2 (NAbs-P2RY2) are present in human plasma, with their clinical relevance in AD unknown. Objective: To explore the alteration of NAbs-P2RY2 in AD patients and its associations with biomarkers and cognition of AD patients. Methods: The levels of naturally occurring antibodies against the four extracellular domains of P2RY2 (NAbs-P2RY2-1, NAbs-P2RY2-2, NAbs-P2RY2-3, and NAbs-P2RY2-4) were measured in the plasma of 55 AD patients, 28 non-AD dementia patients, and 70 cognitively normal participants. The correlations of autoantibody levels with cognitive scale scores, AD plasma biomarkers, and brain amyloid burden were examined. Results: NAbs-P2RY2-1, NAbs-P2RY2-3, and NAbs-P2RY2-4 were reduced in AD patients. Plasma levels of NAbs-P2RY2-2 and NAbs-P2RY2-3 levels were positively associated with cognitive and functional performances. Among these antibodies, plasma NAbs-P2RY2-2 levels were positively associated with plasma amyloid-β 42 levels. While plasma NAbs-P2RY2-3 levels were negatively associated with brain amyloid burden in AD patients. Conclusion: These findings indicate an alteration of humoral immunity against P2RY2 in AD patients. Further mechanistical investigations are needed to reveal the role of NAbs-P2RY2 in the pathogenesis of AD.

As bone marrow transplant (BMT) is gradually applied to the study of central nervous system (CNS) disease, it is needed to investigate the proper dose of chemotherapy to eradicate bone marrow cells while bringing little damage to brain. In the present study, we established a BMT model with varied busulfan and cyclophosphamide (Bu-Cy) dosages. The recipient mice's chimera rate, neuronal death, neuroinflammation, and behavioral functions were all investigated. Chimerism of peripheral blood cells was shown to rise with Bu-Cy treatment doses, with 60.7% in the Bu(20 mg/kg)/Cy(100 mg/kg) group and 93.0% in the Bu(35 mg/kg)/Cy(100 mg/kg) group. Recipients with Bu(35 mg/kg)/Cy(100 mg/kg) therapy had brain injury, increased neuroinflammation, diminished neurogenesis and cognitive abnormalities, whereas animals given a lesser dosage had no such brain damages. Conclusively, considering the chimerism and the possibility to damage brain, we recommend Bu(20 mg/kg)/Cy(100 mg/kg) is the ideal dose in BMT for studying CNS diseases in the C57/BL6 mouse strain.