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This paper proposes a novel aerial manipulator with front cutting effector (AMFCE) to address the aerial physical interaction (APhI) problem. First, the system uncertainty and external disturbance during the system movement and contact operation are estimated by modeling the entire robot and contact position. Next, based on the established model, the nonlinear disturbance observer (NDO) is used to estimate and compensate the unknown external disturbance of the system and the uncertainty of the model parameters in real time. Then, the nonsingular terminal synovial membrane control method is used to suppress the part that is difficult to estimate. Finally, a controller which is suitable for the movement and operation of the entire system is designed. The controller's performance is verified through experiments, and the results show that the design, modeling, and control of the entire system can achieve the APhI. [ABSTRACT FROM AUTHOR]

Electrochemical nanochannel sensors have attracted extensive interest due to their potential applications in biosensing systems. In this work, porous anodized aluminum oxide (AAO) nanochannels are coupled with gold nanoparticles (AuNPs) through a polydopamine (PDA)-induced in situ growth process. It is found that the resulting hybrid nanochannel (denoted as Au-PDA-AAO) can act as both glucose oxidase- and peroxidase-like nanozymes to catalyze the cascade reaction involving glucose. To the best of our knowledge, this is the first report on the synthesis of nanozymes in an AAO nanochannel. Moreover, apart from the nanozyme-catalyzed colorimetric reaction, the Au-PDA-AAO nanochannel could simultaneously serve as a sensitive signal reporter for an electrochemical sensing platform. In such an approach, the glucose oxidation reaction boosts the resistance of the Au-PDA-AAO nanochannel towards ion transport based on the H2O2-mediated size enlargement of AuNPs, resulting in the varied transmembrane ionic current signal of the Au-PDA-AAO nanochannel. On the basis of the changed current–potential properties, the label-free detection of glucose can be achieved with a low detection limit, good reproducibility, and high stability. This work demonstrates the feasibility of the incorporation of versatile nanozymes into AAO nanochannels for mimicking multi-enzymatic catalysis reactions and detecting target analytes. [ABSTRACT FROM AUTHOR]

Objectives: The specific intrinsic network coupling abnormalities in mild traumatic brain injury (mTBI) patients are poorly understood. Our objective is to compare the correlations among the default mode, salience, and central executive networks in patients with mTBI and healthy controls. Methods: This 2-year prospective study included 32 acute mTBI patients and 37 healthy comparisons. We calculated the functional connectivity scores among the default mode, salience, and central executive networks. Then we conducted multilevel correlation analysis to investigate component correlations, global graph, and local functional connectivity changes. Results: Patients with mTBI showed significant increased functional connectivity between the anterior part of the default mode network and the salience network compared with controls (p = 0.013, false discovery rate correction). Hyper-connectivity between the default mode and salience network was significantly positively correlated with the dimensional change card sort score in patients with mTBI (r = 0.40, p = 0.037). The average path length of mTBI patients was significantly higher than that of controls (p = 0.028). Conclusions: Aberrant functional coupling between the default mode and salience networks were identified in acute mTBI patients. Our finding has great potential to improve our understanding of the network architecture of mTBI. [ABSTRACT FROM AUTHOR]

Herein, an electrochemical biosensing platform with acetylcholinesterase (AChE)-catalyzed silver deposition was developed for the ultrasensitive detection of organophosphorus pesticides (OPs). The biosensing mechanism is based on the fact that AChE can catalyze the rapid hydrolysis of indoxyl acetate to form hydroxyindole, which in turn reduces silver ions to metallic silver, resulting in the deposition of silver on the gold electrode. Upon sweeping positive voltages on the gold electrode using linear sweep voltammetry (LSV), the deposited silver on the gold electrode surface undergoes a rapid electrochemical oxidation reaction. Due to its lower oxidation potential under facile conditions with a relatively sharp peak, a small amount of deposited silver generated from AChE-catalysis could result in a significant change in the LSV response. In the presence of OPs, the AChE-catalyzed hydrolysis of indoxyl acetate is blocked, and then the silver deposition on the gold electrode declines, leading to a remarkable decrease in the LSV response and, thus producing a large signal output for the ultrasensitive detection of chlorpyrifos, a proof-of-concept OP in this work. The change in the LSV peak current intensity is linearly correlated with the logarithmic value of the chlorpyrifos concentration ranging from 10 pM to 10 nM with a low detection limit of 4.0 pM. To the best of our knowledge, this is the first example of a biosensing platform for ultrasensitive OP assay using AChE-controlled silver deposition to enhance the output of electronic signals. [ABSTRACT FROM AUTHOR]

Background: Diffusion-weighted imaging (DWI) is a functional modality that indirectly represents the biological characteristics of cancer. However, the correlation of apparent diffusion coefficients (ADCs) to HPV type in patients with cervical cancer is still unknown. Purpose: To explore the relationship between apparent diffusion coefficients calculated by DW-magnetic resonance imaging (MRI) and high-risk human papilloma virus (HR-HPV) infection in cervical squamous cell carcinoma (CSCC) patients. Material and Methods: A total of 315 patients with histologically proven CSCC and who underwent pretreatment MRI were retrospectively analyzed. ADCs on the primary tumor were calculated. Receiver operating characteristic (ROC) curves were employed to determine the cut-off values of ADCmean and accuracy of prediction. Pearson correlation and multivariate logistic regression models were adopted to show the association of HR-HPV infection with clinical and imaging variables. Results: ADCmean for HR-HPV+ CSCC was significantly lower than those for HR-HPV- CSCC. The area under the curve was 0.805 for predicting HR-HPV+ infection using mean ADCs. A cut-off value of 0.885 × 10−3 mm2/s for mean ADCS could distinguish HR-HPV+ from HR-HPV- CSCC with 83.3% sensitivity, 73.9% specificity, and 80.8% accuracy. Regression analysis revealed that the HR-HPV infection was closely associated with tumor ADC value (odds ratio [OR] = 5.588, 95% confidence interval [CI] = 3.371–9.262), FIGO stage (OR = 2.789, 95% CI = 1.631–4.769), and histological grade (OR = 2.333, 95% CI = 1.676–3.247). Conclusion: ADC value is related with the HR-HPV infection in patients with CSCC and DWI may be used for predicting HR-HPV infection in patients with CSCC. [ABSTRACT FROM AUTHOR]

Background and Purpose: Imaging studies of traumatic brain injury demonstrate that the cerebellum is often affected. We aim to examine fractional anisotropy alteration in acute-phase mild traumatic brain injury patients in cerebellum-related white matter tracts. Materials and Methods: This prospective study included 47 mild traumatic brain injury patients in the acute stage and 37 controls. MR imaging and neurocognitive tests were performed in patients within 7 days of injury. White matter integrity was examined by using diffusion tensor imaging. We used three approaches, tract-based spatial statistics, graphical-model-based multivariate analysis, and region-of-interest analysis, to detect altered cerebellar white matter integrity in mild traumatic brain injury patients. Results: Results from three analysis methods were in accordance with each other, and suggested fractional anisotropy in the middle cerebellar peduncle and the pontine crossing tract was changed in the acute-phase mild traumatic brain injury patients, relative to controls (adjusted p-value < 0.05). Higher fractional anisotropy in the middle cerebellar peduncle was associated with worse performance in the fluid cognition composite (r = -0.289, p-value = 0.037). Conclusion: Altered cerebellar fractional anisotropy in acute-phase mild traumatic brain injury patients is localized in specific regions and statistically associated with cognitive deficits detectable on neurocognitive testing. [ABSTRACT FROM AUTHOR]

The aircraft anti-skid braking system (AABS) is an essential aero electromechanical system to ensure safe take-off, landing, and taxiing of aircraft. In addition to the strong nonlinearity, strong coupling, and time-varying parameters in aircraft dynamics, the faults of actuators, sensors, and other components can also seriously affect the safety and reliability of AABS. In this paper, a reconfiguration controller-based adaptive fuzzy active-disturbance rejection control (AFADRC) is proposed for AABS to meet increased performance demands in fault-perturbed conditions as well as those concerning reliability and safety requirements. The developed controller takes component faults, external disturbance, and measurement noise as the total perturbations, which are estimated by an adaptive extended state observer (AESO). The nonlinear state error feedback (NLSEF) combined with fuzzy logic can compensate for the adverse effects and ensure that the faulty AABS maintains acceptable performance. Numerical simulations are carried out in different runway environments. The results validate the robustness and reconfiguration control capability of the proposed method, which improves AABS safety as well as braking efficiency. [ABSTRACT FROM AUTHOR]

Objective To evaluate the aesthetic effect of restorations with custom pressable metal ceramic abutments for defective soft and hard tissue in the maxillary anterior zone. Methods Fifty-two patients with missing anterior teeth in the maxillar were selected, who had problems such as exposure of abutment metal, excessively large angle deviation, excessively long ceramic crown and missing gingival papilla, affecting the aesthetic effect of implant denture. Custom pressable metal ceramic abutments were made on the conventional castable metal abutment surface and restored with all-ceramic crowns to overcome the blackness at the implant neck. Results Clinical evaluation for aesthetic effects 3 and 6 months after the restorations were placed. In 63 restorations of 52 patients, the blackness at the implant neck were eliminated and the aesthetic effect were ideal. The gingival was in healthy condition, showing no further gingival retreat or inflammation around the implant denture. Conclusion Custom pressable metal ceramic abutments can effectively improve the aesthetic appearance of the implant denture in maxillary anterior zone. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The main purpose of this retrospective study is to evaluate clinical outcomes of Xive implants 3-year after insertion. Methods: 219 Xive implants were placed in 139 patients and their clinical effects were evaluated using the Albrektsson Standard. Results: The 3-year survival rate of the Xive implants is 97.26%(213/219). Eleven cases of immediate implants and 15 cases of implant insertion after maxillary sinus lifting all succeeded. The failure ratio is 6/219(2.74%) with failures resulting from excess bone loss in the implant region, peri-implant mucosal inflammation or continuous pain caused by some unknown reasons. Conclusion: Xive implants are clinically effective for the restoration of missing teeth. Immediate implant and implant following maxillary sinus lifting were also successful. [Copyright &y& Elsevier]