Sliding mode coordinated control of hybrid electric vehicle via finite-time control technique.

During the transient mode switching process of the hybrid electric vehicle (HEV) from motor driving mode to hybrid driving mode, dynamic coordinated control of different components is essential to improve the vehicle comfort and dynamic performance. The key to highly quality mode switching control includes fast and stable speed and/or displacement tracking of the engine and motor. The transient mode switching stages of the HEV is divided in this paper. On this basis, by combing the nonlinear sliding mode control and the finite-time stability theory, the global fast integral terminal sliding mode controller (GFITSMC) is designed for the transition stages involving clutch slip. The GFITSMC consists of the global fast integral terminal sliding mode surface (GFITSMS) and the non-smooth reaching law (NSRL). In order to improve the controller convergence and anti-disturbance performance, the proposed controller is synthesized from the perspective of finite-time stability. It is proved that, with proper NSRL and GFITSMS parameters, the speed and displacement tracking error of the motor and engine can reach the sliding mode surface and further converge to zero in a finite time. Simulation and hardware-in-the-loop (HIL) tests are performed to validate the effectiveness of the proposed control method. Research results demonstrate that the proposed strategy not only achieves faster transient mode switching by improving the state trajectory tracking performance, but also reduces the longitudinal jerk caused by the transient mode switching significantly.

Effects of ultrasonic treatment on ovomucin: Structure, functional properties and bioactivity.

The effects of ultrasonic treatment on the structure, functional properties and bioactivity of Ovomucin (OVM) were investigated in this study. Ultrasonic treatment could significantly enhance OVM solubility without destroying protein molecules. The secondary structure changes, including ß-sheet reduction and random coil increase, indicate more disorder in OVM structure. After ultrasonic treatment, the OVM molecule was unfolded partially, resulting in the exposure of hydrophobic regions. The changes in OVM molecules led to an increase in intrinsic fluorescence and surface hydrophobicity. By detecting the particle size of protein solution, it was confirmed that ultrasonic treatment disassembled the OVM aggregations causing a smaller particle size. Field emission scanning electron microscopy (FE-SEM) images showed that ultrasonic cavitation significantly reduced the tendency of OVM to form stacked lamellar structure. Those changes in structure resulted in the improvement of foaming, emulsification and antioxidant capacity of OVM. Meanwhile, the detection results of ELISA showed that ultrasonic treatment did not change the biological activity of OVM. These results suggested that the relatively gentle ultrasound treatment could be utilized as a potential approach to modify OVM for property improvement.

Serum CXCL12/SDF-1 level is positively related with lumbar intervertebral disc degeneration and clinical severity.

This study aimed to examine whether stromal cell-derived factor-1 (SDF-1) or C-X-C chemokine ligand 12 (CXCL12) participates in the development of lumbar disc degeneration, as implicated earlier by the level of CXCL12 correlating with this disease. It enrolled 145 patients with symptomatic lumbar intervertebral disc degeneration (IDD) and 130 asymptomatic healthy controls with no indication of IDD. Radiological assessment of the IDD patients was targeted at the lumbar vertebra region, based on Pfirrmann grade. Degeneration of the multifidus and psoas major muscles was evaluated using Goutallier classification. Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) scores were obtained for assessing the severity of manifestation. The levels of serum CXCL12, IL-6 and TNF-α were determined by ROC curve analysis, resulting in their prognostic value for Pfirrmann grading. Higher levels of serum CXCL12 were found in patients with IDD than in asymptomatic individuals, and were positively related to the Pfirrmann grade as well as multifidus muscle degeneration. Furthermore, serum CXCL12 concentration showed a significant correlation with the VAS and ODI scores. In addition, elevated serum CXCL12 levels were related to serum levels of TNF-α and IL-6. The ROC curve analysis implicated that CXCL12 could function as a biomarker of the early-mediate phase of IDD development. In summary, the serum CXCL12/SDF-1 level is positively related with lumbar IDD and its clinical severity.

Clinical application of auricular point sticking in perioperative hemostasis for elderly patients with intertrochanteric fractures of the femur.

We investigated the clinical application of auricular point sticking (APS) combined with tranexamic acid in perioperative hemostasis in elderly patients with intertrochanteric fractures of the femur.This is a prospective cohort study, and we analyzed 86 elderly patients with intertrochanteric fractures of the femur who underwent closed reduction and internal fixation with proximal femoral nail antirotation (PFNA) between January 2016 and December 2016. The patients were divided into auricular point combined with tranexamic acid group (APS group, n = 43) and tranexamic acid alone group (Control group, n = 43). APS was performed for patients using Vaccaria seeds 1 to 2 days before the operation. The 4 acupoints of hemostasis, including spleen, diaphragm, pituitary, and adrenal gland, as well as acupoint of hip joint, were selected. Routine treatment was performed using tranexamic acid alone in the control group. Blood transfusion, intraoperative, postoperative, and total blood loss were compared between the 2 groups.This study enrolled 36 males and 50 females aged 71 to 93 years (average age: 78.5 years). There were no significant differences in gender, age, height, weight, preoperative hematocrit level, fracture classification, operative time, and hospitalization stay (P > .05). Total blood loss was lower in the APS group than the control group (244.26, 197.87-258.50 ml vs 533.94, 424.00-598.09 ml, P < .01). The blood transfusion rate was 14.0% in the APS group and 34.9% in the control group (P = .02).APS can reduce perioperative bleeding and decrease the need for blood transfusion in elderly patients with intertrochanteric fractures of the femur. This noninvasive method can be applied clinically. Randomized trials may be needed to confirm the findings.