Spectral weight reduction of two-dimensional electron gases at oxide surfaces across the ferroelectric transition.

The discovery of a two-dimensional electron gas (2DEG) at the [Formula: see text] interface has set a new platform for all-oxide electronics which could potentially exhibit the interplay among charge, spin, orbital, superconductivity, ferromagnetism and ferroelectricity. In this work, by using angle-resolved photoemission spectroscopy and conductivity measurement, we found the reduction of 2DEGs and the changes of the conductivity nature of some ferroelectric oxides including insulating Nb-lightly-substituted [Formula: see text], [Formula: see text] (BTO) and (Ca,Zr)-doped BTO across paraelectric-ferroelectric transition. We propose that these behaviours could be due to the increase of space-charge screening potential at the 2DEG/ferroelectric regions which is a result of the realignment of ferroelectric polarisation upon light irradiation. This finding suggests an opportunity for controlling the 2DEG at a bare oxide surface (instead of interfacial system) by using both light and ferroelectricity.

Epitope Analysis and Efficacy Evaluation of Phosphatase 2C (PP2C) DNA Vaccine Against Toxoplasma gondii Infection.

Toxoplasma gondii infects almost all warm-blooded animals and negatively affects the health of a wide range of these animals, including humans. Protein phosphatase 2C (PP2C) is a T. gondii protein secreted by rhoptry organelles during host cell invasion. However, very little is known about whether this protein can induce protective immunity against T. gondii. In this study, bioinformatics analysis of PP2C revealed some useful information in the context of anti-toxoplasmosis treatments and vaccine research. In addition, the PP2C gene was amplified, and a eukaryotic expression vector (pEGFP-PP2C) was successfully constructed to express PP2C. Finally, the constructed pEGFP-PP2C was injected into mice to evaluate whether it could induce immunoprotection. Compared with the control groups, we found that immunizations with the pEGFP-PP2C plasmid could elicit specific IgG antibodies and cytokines against T. gondii infection. The survival of mice immunized with the pEGFP-PP2C plasmid was significantly prolonged compared with that of the control group mice. Based on the ability of pEGFP-PP2C to induce specific immune responses against T. gondii, we propose that PP2C merits consideration as a potential vaccine candidate against toxoplasmosis.

[Relationships between percentage of skeletal muscle mass and cardiorespiratory fitness in elderly patients with coronary heart disease].

Objective: To determine the relative percentage of skeletal muscle mass (SMM) in elderly patients with coronary heart disease, analyse the relationship between percentage of SMM and cardiorespiratory fitness (CRF), predict exercise capacity and cardiac reserve. Methods: Patients aged 65 years and over after PCI, receiving cardiopulmonary exercise testing (CPET) during February 2014 to December 2016 in Department of Cardiology at Peking University Third Hospital were enrolled.All patients' basic data, percentage of SMM and CPET related parameters, including peak oxygen uptake (VO(2)peak), oxygen pulse (VO(2)/HR), oxygen uptake efficiency slope (OUES) and other cardiorespiratory endurance indicators were collected, to do correlation analysis. Results: There were 402 patients enrolled, with average age (71±5) years, including 283 cases of male (70.40%) and 119 cases of female patients (29.60%). There were 62 patients with acute myocardial infarction (15.42%), 113 patients with old myocardial infarction (28.11%), and 227 patients diagnosed with angina pectoris (56.47%). The percentage of SMM was correlated to CRF.The percentage of SMM[97.00 (92.05, 102.10)%] and VO(2)/HR (r=0.231, P<0.001) and OUES (r=0.264, P<0.001) were positively correlated.Body mass index was negatively correlated with VO(2)peak(r=-0.162, P=0.001). Visceral fat area (VFA) was also negatively correlated with VO(2)peak(r=-0.126, P=0.016). Multiple linear regression analysis showed that Body mass index and VFA were negatively correlated with VO(2)peak (r=-0.204, P=0.014; r=-0.031, P=0.013). The percentage of SMM was positively independently correlated with OUES(r=11.020, P<0.001). Conclusions: Muscle content is positively correlated with exercise capacity of patients.The percentage of skeletal muscle mass determines the core index of cardiorespiratory fitness, such as the slope of oxygen pulse and oxygen uptake efficiency.These indexes can be used as an important criterion for predicting and guiding rehabilitation exercise in patients with coronary heart disease.

Contact Behavior of Composite CrTiSiN Coated Dies in Compressing of Mg Alloy Sheets under High Pressure.

Hard coatings have been adopted in cutting and forming applications for nearly two decades. The major purpose of using hard coatings is to reduce the friction coefficient between contact surfaces, to increase strength, toughness and anti-wear performance of working tools and molds, and then to obtain a smooth work surface and an increase in service life of tools and molds. In this report, we deposited a composite CrTiSiN hard coating, and a traditional single-layered TiAlN coating as a reference. Then, the coatings were comparatively studied by a series of tests. A field emission SEM was used to characterize the microstructure. Hardness was measured using a nano-indentation tester. Adhesion of coatings was evaluated using a Rockwell C hardness indentation tester. A pin-on-disk wear tester with WC balls as sliding counterparts was used to determine the wear properties. A self-designed compression and friction tester, by combining a Universal Testing Machine and a wear tester, was used to evaluate the contact behavior of composite CrTiSiN coated dies in compressing of Mg alloy sheets under high pressure. The results indicated that the hardness of composite CrTiSiN coating was lower than that of the TiAlN coating. However, the CrTiSiN coating showed better anti-wear performance. The CrTiSiN coated dies achieved smooth surfaces on the Mg alloy sheet in the compressing test and lower friction coefficient in the friction test, as compared with the TiAlN coating.

[Changes of airway responsiveness, and relative factors in asthmatics with remission at puberty].

OBJECTIVE: To study the airway responsiveness and relative factors in asthmatics with natural remission at puberty. METHOD: The airway responsiveness was evaluated by challenge of methacholine (PC20), blood sIL-2R, eosinophil count, basophil count and basophil releasability were detected in 18 asthmatics with remission at puberty (group I), in 20 asthmatics without remission at puberty (group II), and in 30 healthy controls (group III). RESULT: The mean value of PC20 in the group I was significantly lower than that of the group III (P < 0.01), but still higher than that of the group II (P < 0.01). The blood sIL-2R and eosinophil values were droped almost to those of the group III, significantly lower than those of the group II. The basophil value and positive rate of human basophil degranulation test stimulated by mannitol with hyperosmolarity were still abnormal, significantly higher than those of the group III, and the basophil level was significantly related to the airway responsiveness. CONCLUSION: The asthmatics with remission at puberty have a certain degree of airway hyperresponsivenes that is related to the abnormal of basophil.