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Toona sinensis, popularly known as Chinese toon or Chinese mahogany, is a perennial deciduous arbor belonging to the genus Toona in the Meliaceae family, which is widely distributed and cultivated in eastern and southeastern Asia. Its fresh young leaves and buds have been consumed as a very popular nutritious vegetable in China and confirmed to display a wide variety of biological activities. To investigate the chemical constituents and their potential health benefits from the fresh young leaves and buds of T. sinensis, a phytochemical study on its fresh young leaves and buds was therefore undertaken. In our current investigation, 16 limonoids (1-16), including four new limonoids, toonasinenoids A-D (1-4), and a new naturally occurring limonoid, toonasinenoid E (5), were isolated and characterized from the fresh young leaves and buds of T. sinensis. The chemical structures and absolute configurations of limonoids 1-5 were elucidated by comprehensive spectroscopic data analyses. All known limonoids (6-16) were identified via comparing their experimental spectral data containing mass spectrometry data, 1H and 13C nuclear magnetic resonance data, and optical rotation values to the data reported in the literature. All known limonoids (6-16) were isolated from T. sinensis for the first time. Furthermore, the neuroprotective effects of all isolated limonoids 1-16 against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells were assessed in vitro. Limonoids 1-16 exhibited notable neuroprotective activities, with EC50 values in the range from 0.27 ± 0.03 to 17.28 ± 0.16 μM. These results suggest that regular consumption of the fresh young leaves and buds of T. sinensis might prevent the occurrence and development of Parkinson's disease (PD). Moreover, the isolation and characterization of these limonoids that exhibit notable neuroprotective activities from the fresh young leaves and buds of T. sinensis could be very significant for researching and developing new neuroprotective drugs used for the prevention and treatment of PD.

Ti3C2 Tx nanosheet, the first synthesized MXene with high capacity performance and charge/discharge rate, has attracted increasingly attention in renewable energy storage applications. By performing systematic density functional theory calculations, the theoretical capacity of the intrinsic structure of single- and multi-layered Ti3C2 T 2 (T = F or O) corresponding to M (M = Li and Na) atoms are investigated. Theoretical volumetric capacity and gravimetric capacity are obtained, which are related to the stacking degree. The optimal ratios of capacity to structure are determined under different stacking degrees for understanding the influence of surface functional groups on energy storage performance. Its performance can be tuned by performing surface modification and increasing the interlayer distance. In addition, the reason for theoretical capacity differences of M atoms is analyzed, which is attributed to difference in interaction between the M-ions and substrate and the difference in electrostatic exclusion between adsorbed M-ions. These results provide an insight into the understanding of the method of efficiently increasing the energy storage performance, which will be useful for designing and using high performance electrode materials.

The truss structure has characteristics of small mass with high rigidity etc., so it is still practical in structures and researched by engineers and scientists. Here a truss structure with the paraboloid top surface is presented; several truss forms of the octahedral space units are connected into it. The equilibrium matrix is calculated by the force-density method. From the equilibrium matrix, number of the self-stress mode and number of the displacement mode of the structure is calculated. According to the obtained result, the structure is proved to be in equilibrium. Through the ANSYS software, the truss structure is researched for deformation under outer forces and it is proved that the structure has certain rigidity and withholding capacity.

In order to research the working status of the field-modulated asynchronous magnetic coupling under loading condition, the electromagnetism characteristics such as the distributions of induced current, torque and loss were obtained by using the ANSOFT software to carry on the transient analysis. The results show that the induced current in the whole of magnetic coupling is not evenly distributed. The induced current of copper is maximum, followed by the ferromagnetic pole-pieces. The highest induced current density is in the outside boundary of the copper layer so that the skin effect of current is verified. The current density and loss increases with increasing of the workload, while the torque increases firstly and then decreases with increasing of the workload. When the slip ratio exceeds 12%, the coupling appear skid phenomenon because the loads is greater than the maximum load which the coupling can bear.

A field-modulated asynchronous magnetic coupling is a new type of composite magnetic transmission mechanism, which is based on the principles of magnetic field modulation and electromagnetic induction. The rotational velocity and direction of the inner conductor rotor could be changed, since the magnetic field generated by permanent magnet outer rotor is modulated by ferromagnetic pole-pieces. Therefore, the couplings can meet special conditions with special requirements for load and speed. The formula of the modulated magnetic flux density of inner air gap is analyzed through magnetic field analytic approaches, and then the formula of transmission ratio is also deduced by introducing slip ratio in the mean time. Finally, experimental research of the coupling is conducted. The results show that the transmission ratio of the coupling is not only related to the ratio of the number of pole pairs on outer permanent magnet rotor and the number of pole pairs of magnetic field flux density harmonic, but also related to the slip ratio. Besides, the transmission ratio of the coupling increases non-linearly with the slip ratio.

The corrosion mechanisms of as-cast Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr Mg alloys in 5% NaCl aqueous solution were investigated by electrochemical testing and SEM observation. The electrochemical results indicated that the corrosion resistance of Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr alloys in 5% NaCl aqueous solution gradually deteriorated with increasing of immersion time expect for 2h and 24h immersion. The Cl- anion led to the initiation and development of the corrosion pits. The cathodic reaction was driven by hydrogen evolution reaction. The presence of filiform corrosion also proved a resistant oxide film naturally formed on the surface of Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr alloys. The corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr was better than Mg-8Y.

Pseudomonas fluorescens GcM5-1A was isolated from the pine wood nematode (PWN), Bursaphelenchus xylophilus, obtained from wilted Japanese black pine, Pinus thumbergii, in China. In this paper, a genomic library of the GcM5-1A strain was constructed and a toxin-producing clone was isolated by bioassay. Nucleotide sequence analysis revealed an open reading frame of 1,290 bp encoding a protein of 429 amino acids with N-terminal putative signal peptide of 36 amino acids, which shared a similarity of 83, 82 and 80% identity with hypothetical protein PFLU2919 from P. fluorescens SBW25, Dyp-type peroxidase family protein from P. fluorescens Pf-5 and Tat-translocated enzyme from P. fluorescens Pf0-1, respectively. The gene encoding a full-length protein or without the putative signal peptide was cloned and expressed as a soluble protein in E. coli. The recombinant protein was purified to electrophoretic homogeneity by affinity chromatography using a Ni2+ matrix column. Its relative molecular weight was estimated to be 48.5 kDa by SDS-PAGE for full-length protein, and 45.0 kDa for the recombinant protein without putative signal peptide. Bioassay results showed that the recombinant protein with or without the putative signal peptide was toxic to both suspension cells and P. thunbergii seedlings. HPLC analysis demonstrated that components in branch extracts of P. thunbergii were significantly changed after addition of the recombinant full-length protein and hydrogen peroxide, which indicated that it is probably a peroxidase. This study offers information that can be used to determine the mechanism of pine wilt disease caused by the PWN.

OBJECTIVE To evaluate the usefulness of a fasting plasma glucose (FPG) at 24–28 weeks’ gestation to screen for gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS The medical records and results of a 75-g 2-h oral glucose tolerance test (OGTT) of 24,854 pregnant women without known pre-GDM attending prenatal clinics in 15 hospitals in China were examined. RESULTS FPG cutoff value of 5.1 mmol/L identified 3,149 (12.1%) pregnant women with GDM. FPG cutoff value of 4.4 mmol/L ruled out GDM in 15,369 (38.2%) women. With use of this cutoff point, 12.2% of patients with mild GDM will be missed. The positive predictive value is 0.322, and the negative predictive value is 0.928. CONCLUSIONS FPG at 24–28 weeks’ gestation could be used as a screening test to identify GDM patients in low-resource regions. Women with an FPG between ≥4.4 and ≤5.0 mmol/L would require a 75-g OGTT to diagnose GDM. This would help to avoid approximately one-half (50.3%) of the formal 75-g OGTTs in China.

To summarize and analyze the clinical indication, surgical techniques and results of percutaneous antegrade Kirschner pinning in the treatment of proximal fracture of humerus.Thirty-two patients with displaced fractures of the proximal humerus were treated with 2 to 3 Kirschner wires by percutaneous antegrade transfixation. Among 32 casas, there were 7 male and 25 female, with a mean age of 49.25 years (range, from 28 to 75 years). According to the Neer fracture classification, there were 20 cases of 2-part, 9 of 3-part, and 3 of 4-part fractures.All patients were followed up for 8 to 34 months with an average of 13.5 months. According to Constant-Murley evaluation, the results were excellent in 21 cases, good in 9, fair in 2.Percutaneous antegrade transfixaton is a good technique for the management of displaced 2-part fractures of the proximal humerus and also alternative to 3-part or 4-part fractures.