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This paper proposes a real-time NMPC-based controller for four-wheel independent motor-drive electric vehicles to improve vehicle longitudinal and lateral stability under extreme driving conditions. First, considering the interactive and highly coupled longitudinal-lateral vehicle dynamics, a combined-slip tire model is applied to develop the stability controller on low friction coefficient surfaces. Second, the wheel slip ratios and slip angles are selected as the virtual control inputs of the NMPC controller to concurrently achieve three main control objectives: Slip control, lateral stability control, and handling performance improvement. Simultaneously, multiple safety constraints are contained. Then, based on the dynamic relationships between the longitudinal tire force and virtual control inputs, the wheel slip ratios and slip angles obtained from the NMPC controller are converted into additional torques acting directly on each wheel. Finally, the control performance is investigated by co-simulation with MATLAB/Simulink and CarSim, and a hardware-in-the-loop simulation system. The effect of uncertainties on control performance is also verified. The results show that the proposed controller can rapidly solve the optimization problem, and vehicle overall stability are efficiently enhanced under extreme conditions. The robustness of the controller is proved with uncertainties on the road adhesion coefficient and vehicle mass.

Respiratory failure is a common cause of pulseless electrical activity (PEA) and asystolic cardiac arrest, but the changes in heart rate (HR) pre-arrest are not well described. We describe HR dynamics prior to in-hospital cardiac arrest (IHCA) among PEA/asystole arrest patients with respiratory etiology.In this retrospective study, we evaluated 139 patients with 3-24 hours of continuous electrocardiogram data recorded preceding PEA/asystole IHCA from 2010-2017. We identified respiratory failure cases by chart review and evaluated electrocardiogram data to identify patterns of HR changes, sinus bradycardia or sinus arrest, escape rhythms, and development right ventricular strain prior to IHCA.A higher proportion of respiratory cases (58/73, 79 %) fit a model of HR response characterized by tachycardia followed by rapid HR decrease prior to arrest, compared to non-respiratory cases (30/66, 45 %, p 0.001). Among the 58 respiratory cases fitting this model, 36 (62 %) had abrupt increase in HR occurring 64 (IQR 23-191) minutes prior to arrest, while 22 (38 %) had stable tachycardia until time of HR decrease. Mean peak HR was 123 ± 21 bpm. HR decrease occurred 3.0 (IQR 2.0-7.0) minutes prior to arrest. Sinus arrest occurred during the bradycardic phase in 42/58 of cases; escape rhythms were present in all but 2/42 (5 %) cases. Right ventricular strain ECG pattern, when present, occurred at a median of 2.2 (IQR -0.05-17) minutes prior to onset of HR decrease.IHCAs of respiratory etiology follow a model of HR increase from physiologic compensation to hypoxia, followed by rapid HR decrease prior to arrest.

The current methods for treatment of giant gastric bezoars mainly include chemical dissolution, endoscopic fragmentation, and surgical removal, which often have limited curative effects or generate multiple adverse events. Therefore, there is an urgent need to find new methods to overcome such a dilemma. The aim of this study was to evaluate the safety, efficacy, and feasibility of a novel guidewire-based tangential sawing fragmentation (GTSF) technique to treat giant gastric bezoars.This retrospective single-center study was performed in the Department of Gastroenterology and Hepatology, Sichuan Academy of Medical SciencesSichuan Provincial People's Hospital. Ten patients with giant bezoars were consecutively enrolled from December 8, 2019 to April 8, 2021. We treated the 10 patients with the GTSF technique, recorded the GTSF procedure, and followed the patients with gastroscopy 2 weeks after the procedure.All patients were successfully treated by the GTSF technique, and the giant bezoar was broken into small pieces (2 cm in diameter). The average operation time was 21.73 minutes, and the average fragmentation time was 8.06 minutes. Ten patients treated with the GTSF technique attained satisfactory treatment results, with no acute adverse events or alimentary canal injury during the procedure, and no bezoar residue remained as shown by gastroscopy 2 weeks after the procedure.The GTSF technique is a safe, effective, and feasible method for removing giant bezoars and can be considered as an alternative treatment of this disease.

Pospartum Depression (PPD) causes significant adverse effects on mothers and their offspring. The condition is considered to have multiple pathogenic factors. However, the underlying neural basis of these factors keeps unclear.A group of 86 patients with PPD and 74 Healthy Postnatal Women (HPW) were enrolled in this structural Magnetic Resonance Imaging (MRI) study. Between-groups differences in regional gray matter volume (rGMV) were measured and association and mediation analyses were performed to investigate the relationship between rGMV, PPD severity and a range of demographic/clinical factors which could contribute to PPD.Relative to HPW, PPD patients had higher scores indicating adverse effects on most questionnaires and higher prolactin levels, as well as increased rGMV in left dorsolateral prefrontal cortex (DLPFC) and right anterior insular (anI). In PPD patients, rGMV in right anI was positively correlated with prolactin level, PPD severity, and the number of children raised, whereas rGMV in left DLPFC was negatively correlated with education and age. Besides, prolactin level was found to mediate the association between rGMV in anI and PPD symptoms.Potentially factors such as fertility or delivery pattern were not studied.Our results provide information on the risk and protective factors, and rGMV abnormalities, associated with PPD. The finding that prolactin level mediated the impact of rGMV in right anI on PPD symptoms is a potential mechanism for explaining the association between brain structure and PPD symptoms. Increased understanding of the neuro-pathophysiology of PPD is important for early diagnosis and treatment.

One of the most effective and promising strategies to develop novel biomaterials with unique, tunable structure and physicochemical properties is by creating composite materials that combine synthetic polymers with natural proteins using ionic liquids. In this study, biodegradable poly(d,l-lactic acid) (PDLLA) was blended with silk fibroin (SF) to create biocompatible films using an ionic liquid-based binary solvent system (1-butyl-3-methylimidazolium chloride/N,N-dimethylformamide), which can maintain the molecular weights of the proteins/polymers and encourage intermolecular interactions between the molecules. The effects of varying the ratio of PLA to SF were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), water contact angle testing, and cytotoxicity analysis as well as enzymatic degradation. Results showed that the composite films were homogeneously blended on the macroscopic scale and exhibited typical fully miscible polymer blend characteristics. By increasing the SF content in the composites, the amounts of β-sheets in the films were significantly increased, allowing for SF to act as a physical crosslinker to maintain the stability of the protein-polymer network. Additionally, SF significantly improved the hydrophilicity and biocompatibility of the material and promoted the self-assembly of micelle structures in the biocomposites. Different topologies in the films also provided beneficial surface morphology for cell adhesion, growth, and proliferation. Overall, this study demonstrated an effective fabrication method for a fine-tuned polymer blends combining synthetic polymer and protein for a wide variety of biomedical and green material applications.