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In this work, Ca-doped lithium manganese oxides Li0.98Ca0.02Mn2O4 were successfully synthesized via a facile hydrothermal method followed by calcination. The evolution of the microstructures and electrochemical performance were investigated in detail. XRD identified that pure spinel phase with the enlarged lattice constants were observed in Ca-doped samples. SEM revealed that powders had a hollow hemispherical morphology composed of stacked nanoparticles. Ca doping can improve the electrochemical performance of LiMn2O4. Galvanostatic charge-discharge tests demonstrated that Li0.98Ca0.02Mn2O4 calcined at 550°C could deliver the initial discharge capacity of 108.6 mA h/g with the capacity retention of 91.4% after 100 cycles at 2 C. The results indicate that Ca-doped LiMn2O4 is a promising cathode material. [ABSTRACT FROM AUTHOR]

BiFeO3-based ceramics is the high-temperature piezoelectric material with great potential applications. In this paper, the evolution of structure and properties of BiFeO3–(Ba0.85Ca0.15)(Ti0.9Hf0.1)O3 (BFO–BCTH) ceramics was investigated. XRD analysis showed that rhombohedral R3c phase and pseudocubic (PC) phase coexisted in all samples, and the content of PC phase increased with the increase of BCTH content. Two dielectric anomalies were observed for all BFO–BCTH samples. Among them, the dielectric relaxation at 300–500 °C exhibited a significant frequency dispersion. Besides, a frequency-independent dielectric anomaly was detected for all samples, accompanied with thermal hysteresis, indicating the primary ferroelectric phase transition, and the peak temperature slightly decreased with increasing BCTH content. The leakage current density significantly decreased with increasing doping BCTH content, and the ferroelectric and piezoelectric properties were enhanced for x = 0.25–0.27 samples. The magnetic properties of the moderately doped ceramics were significantly improved, but the magnetic dilution due to the increase in doping content led to a decrease in magnetization intensity instead. [ABSTRACT FROM AUTHOR]

Beta-1,3-glucanosyltransferase (Gas1p) plays important roles in cell wall biosynthesis and morphogenesis and has been implicated in DNA damage responses and cell cycle regulation in fungi. Yeast Gas1p has also been reported to participate in endoplasmic reticulum (ER) stress responses. However, the precise roles and molecular mechanisms through which Gas1p affects these responses have yet to be elucidated. In this study, we constructed GAS1-deficient (gas1Δ) and GAS1-overexpressing (GAS1 OE) yeast strains and observed that the gas1Δ strain exhibited a decreased proliferation ability and a shorter replicative lifespan (RLS), as well as enhanced activity of the unfolded protein response (UPR) in the absence of stress. However, under the high-tunicamycin-concentration (an ER stress-inducing agent; 1.0 μg/mL) stress, the gas1Δ yeast cells exhibited an increased proliferation ability compared with the wild-type yeast strain. In addition, our findings demonstrated that IRE1 and HAC1 (two upstream modulators of the UPR) are required for the survival of gas1Δ yeast cells under the tunicamycin stress. On the other hand, we provided evidence that the GAS1 overexpression caused an obvious sensitivity to the low-tunicamycin-concentration (0.25 μg/mL). Collectively, our results indicate that Gas1p plays an important role in the ageing and ER stress responses in yeast. [ABSTRACT FROM AUTHOR]

In the title Schiff base compound, C(14)H(11)N(3)O(5), the dihedral angle between the two benzene rings is 1.6 (1)°. The mol-ecule displays an E configuration about the C=N bond. An intra-molecular O-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked into layers parallel to (101) by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds. One of the hydroxyl groups is disordered over two positions, with occupancies of 0.643 (5) and 0.357 (5).

In the chiral title compound, C(38)H(28)O(4)P(2), the intra-molecular P⋯P separation is 3.671 (2) Å and the dihedral angle between the two benzene rings in the biphenyl unit is 77.9 (2)°.

Objective: To investigate the clinicopathologic features of gastrointestinal stromal tumors (GISTs) and to identify reliable prognostic parameters., Methods: Fifty-nine GISTs were studied by immunostaining of CD117, CD34, SMA, desmin, S-100, bcl-2, and Ki-67. Histopathologic evaluations included tumor size, necrosis, histological growth patterns, mitotic activities and tumor lymphocytic infiltrate. The patients were clinically followed for 2 to 9 years. Univariate, multivariate and correlative statistical evaluations were used to analyze the data., Results: Among the 59 patients, 40 were alive and 15 died of their tumors at follow-up, the remaining 4 patients died of other causes. Pathological parameters that correlated with prognosis included tumor sizes of more than 5 cm, tumor tissue necrosis, mitotic cell count equal or higher than 5 per 50 high power field, Ki-67 labeling index (LI) equal or higher than 5% and intense bcl-2 immunostaining. Multivariate analysis showed that the mitotic count and Ki-67 LI were independent prognostic indicators. There was a correlation between mitotic count and Ki-67 LI., Conclusions: Mitotic count and Ki-67 LI are the best predictors for a poor outcome of GIST after surgical treatment. Ki-67 immunostaining may substitute mitotic count as a useful prognostic parameter.

Aim: To develop a rapid and sensitive LC/MS/MS method for the analysis of levodropropizine in plasma and study the pharmacokinetics of levodropropizine in healthy Chinese volunteers., Methods: Levodropropizine and zolmitriptan (internal standard, IS) were extracted from plasma samples and chromatographed on a C18 column and detected using a tandem mass spectrometer with a TurboIon Spray ionization interface. Quantitation was performed using multiple reaction monitoring (MRM) of the transitions of the m/z 237 --> m/z 120 for levodropropizine and m/z 288 --> m/z 58 for the IS., Results: The limit of quantification of the method for levodropropizine was 0.25 microg x L(-1). The assay was linear over the concentration range from 0.25 to 500.0 microg x L(-1) and intra- and inter-day precision over this range were < 11.4% with good accuracy., Conclusion: The method is shown to be accurate, and suitable for clinical pharmacokinetic study of levodropropizine.