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Perovskite ferroelectric oxides are usually considered to be brittle materials; however, recent work [Dong et al., Science 366, 475 (2019)] demonstrated the super-elasticity in the freestanding BaTiO3 thin films. This property may originate from the ferroelectric domain evolution during the bending, which is difficult to observe in experiments. Therefore, understanding the relation among the bending deformation, thickness of the films, and domain dynamics is critical for their potential applications in flexible ferroelectric devices. Here, we reported the dynamics of ferroelectric polarization in the freestanding BaTiO3 ultrathin films in the presence of large bending deformation up to 40 using phase-field simulation. The ferroelectric domain evolution reveals the transition from the flux-closure to a/c domains with "vortex-like" structures, which is caused by the increase in out-of-plane ferroelectric polarization. Additionally, by varying the film thickness in the identical bending situation, we found that the a/c phase with a vortex-like structure emerges only as the film thickness reached 12nm or higher. The results from our investigations provide instructive information for the microstructure evolution of bending ferroelectric perovskite oxide films, which could serve as a guide for the future application of ferroelectric films on flexible electronic devices. [ABSTRACT FROM AUTHOR]

Objective: To observe the medial vastus muscular trigger point energy metabolism (adenine nucleotide, lactic acid) changes due to acupotomy intervention and the biological mechanism of treating myofascial pain syndrome with acupotomy using a rat model with myofascial pain syndrome. Methods: The trigger point model rats were established by the method of crush plus eccentric exercise. The pathological variation of trigger points of rats was observed by electrophysiology. The expression of adenine nucleotide and lactic acid on trigger points was verified through high performance liquid chromatography (HPLC) and the colorimetric method. Differences among groups were then analyzed. Results: At the end of 8th week of modeling, in the model group, the levels of adenine nucleotide declined significantly (P < 0.05), and the levels of lactic acid increased significantly (P < 0.05). After three rounds of acupotomy treatment, the levels of adenine nucleotide in the acupotomy therapy group significantly increased, and the levels of lactic acid in the acupotomy therapy group significantly declined compared with those in the model group (P < 0.01). There were also significant differences of adenine nucleotide and lactic acid between the acupotomy therapy group and the normal group after three rounds of acupotomy treatment (P < 0.05). Conclusions: Through releasing and activating the trigger points, acupotomy may promote the release of adenine nucleotide and inhibit the secretion of lactic acid in the local site, improving the continued contracting condition of muscles and reducing the accumulation of metabolic products. In this way, acupotomy may break the vicious cycle and finally cure the myofascial pain syndrome. [ABSTRACT FROM AUTHOR]

Reports on the adoption of strain models to predict the spatial distribution of the eutectic M 2B borides in Fe-Cr-B cast irons, family of ferrous alloys containing high chromium and boron. Success of the models in the prediction of the spatial distribution of the eutectic borides; Distribution of the large hard phases in Fe-Cr-B cast irons in the matrix grains somewhere between extreme cases.

Adipose-derived stem cells (ASCs) are highly chondrogenic and can be used to treat knee osteoarthritis (KOA) by alleviating cartilage defects. Acupotomy, a biomechanical therapy guided by traditional Chinese medicine theory, alleviates cartilage degradation and is widely used in the clinic to treat KOA by correcting abnormal mechanics. However, whether combining acupotomy with ASCs will reverse cartilage degeneration by promoting chondrocyte proliferation in KOA rabbits is unknown. The present study aimed to investigate the effects of combination therapy of acupotomy and ASCs on chondrocyte proliferation and to determine the underlying mechanism in rabbits with KOA induced by knee joint immobilization for 6 weeks. After KOA modeling, five groups of rabbits (acupotomy, ASCs, acupotomy + ASCs, model and control groups) received the indicated intervention for 4 weeks. The combination therapy significantly restored the KOA-induced decrease in passive range of motion (PROM) in the knee joint and reduced the elevated serum level of cartilage oligomeric matrix protein (COMP), a marker for cartilage degeneration. Furthermore, magnetic resonance imaging (MRI) and scanning electron microscopy (SEM) images showed that the combination therapy inhibited cartilage injury. The combination therapy also significantly blocked increases in the mRNA and protein expression of glycogen synthase kinase-3β (GSK3β) and decreases in the mRNA and protein expression of cyclin D1/CDK4 and cyclin D1/CDK6 in cartilage. These findings indicated that the combination therapy mitigated knee joint immobility, promoted chondrocyte proliferation and alleviated cartilage degeneration in KOA rabbits, and these effects may be mediated by specifically regulating the GSK3β-cyclin D1-CDK4/CDK6 pathway. [ABSTRACT FROM AUTHOR]

Introduction: The knives for endoscopic submucosal dissection (ESD) have their strengths as well as shortcomings. They need to be used in combination in most cases. The Dual knife is a relatively novel type of ESD knife produced in 2009, which can be used for completing the whole procedure of ESD. Aim: Colorectal laterally spreading tumors (LSTs) are a special subtype of colorectal neoplasms. We aimed to evaluate the clinical features and outcomes of ESD for colorectal LSTs only using the Dual knife from our experience. Material and methods: This retrospective study included 162 patients (each patient had 1 lesion) with colorectal LSTs treated by ESD with the Dual knife by a single endoscopist at our hospital between June 2015 and January 2018. We analyzed the clinical features and outcomes after resection. Results: We obtained the en bloc ESD of the colorectal LSTs and the complete histological assessment in all patients. The mean age of the patients was 53.9 years. The mean diameter of lesions was 46 mm. The most common location of LSTs was the rectum. The most common histological type was tubular adenoma with 63 cases. The mean operating time was 56 min. Perforation and bleeding rates were 0.6% and 0.6%, respectively. No cases of local persistence or recurrence were observed at a follow-up endoscopy 6 to 31 months after the en bloc resection. Conclusions: The ESD using the Dual knife only for colorectal LSTs has the advantages of safety, efficiency, and minimally invasiveness. It is worthy of widespread clinical application. [ABSTRACT FROM AUTHOR]

A series of Cu-X/γ-Al2O3 (X = Fe, Co, Ni) catalysts were synthesized by a rapid intermittent microwave irradiation method for hydrogen generation from dimethyl ether steam reforming. Different parameters, such as the promoters of X (X = Fe, Co, Ni), microwave irradiation procedure and the ratio of metal to γ-Al2O3, were investigated. The results show that 2Cu-Fe/72γ-Al2O3 has the best performance, for which the agglomeration is prevented, CuO is well dispersed and the catalytic activity is improved. Promoter iron oxide in 2Cu-Fe/9γ-Al2O3 facilitates the watergas shift reaction, which lead to an increase in the conversion of CO to CO2 and hydrogen yield. Particularly, the 2Cu-Fe/72γ-Al2O3 catalyst, with the best molar ratio of metal to γ-Al2O3, shows a dimethyl ether conversion of >99% and a hydrogen yield of >98% and produces the lowest CO content of 1.4%, indicating that the synergism between dimethyl ether hydrolysis and methanol reforming requires an appropriate balance between the metallic Cu-Fe and the acid γ-Al2O3. The intermittent microwave irradiation technique provides a simple but effective method of the Cu-Fe/γ-Al2O3 synthesis with a good catalyst performance for the dimethyl ether steam reforming. [ABSTRACT FROM AUTHOR]

Face liveness detection aims to distinguish genuine faces from disguised faces. Most previous works under visible light focus on classification of genuine faces and planar photos or videos. To handle the three-dimensional (3-D) disguised faces, liveness detection based on multispectral images has been shown to be an effective choice. In this paper, a gradient-based multispectral method has been proposed for face liveness detection. Three feature vectors are developed to reduce the influence of varying illuminations. The reflectance-based feature achieves the best performance, which has a true positive rate of 98.3% and a true negative rate of 98.7%. The developed methods are also tested on individual bands to provide a clue for band selection in the imaging system. Preliminary results on different face orientations are also shown. The contributions of this paper are threefold. First, a gradient-based multispectral method has been proposed for liveness detection, which considers the reflectance properties of all the distinctive regions in a face. Second, three illumination-robust features are studied based on a dataset with two-dimensional planar photos, 3-D mannequins, and masks. Finally, the performance of the method on different spectral bands and face orientations is also shown in the evaluations. [ABSTRACT FROM AUTHOR]