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CaBiCu3Ti4O ( = 0.0, 0.1, 0.2 and 0.3; BCCTO) ceramics were prepared by traditional solid-state sintering method. All samples had pure cubic perovskite-like structure. A drastic grain size reduction was observed with bismuth doping. Dielectric spectra showed two obvious relaxation steps corresponding to two series of peaks in the imaginary part of electric modulus spectra and dielectric loss spectra too. Activation energy fitting by electric modulus spectra reflected different conducting segments in BCCTO ceramics of grains and oxygen vacancies below room temperature. Normalized capacitance dependent of extra bias showed different voltage-capacitance coefficients at special frequencies that suggested multirelaxation mechanisms related with grain and oxygen vacancy. A positive capacitance curvature implies dipolar relaxations in CCTO grains. Whereas a negative curvature suggests oxygen-related relaxations at the interface. [ABSTRACT FROM AUTHOR]

The temperature and frequency dependence of capacitance versus voltage ( C- V) curves was investigated for ceramic CaCu3 Ti4 O12 samples sintered in atmospheres of vacuum, air and oxygen, respectively. A drastic capacitance rise at higher dc voltages and low ac frequencies was observed for all these CaCu3Ti4O12 CCTO samples, and it is especially strong for the sample sintered in vacuum, which has not been found previously. The shape as well as the asymmetry of the C- V curves suggest that the dielectric behavior is related to charged trap states. It also indicates that a slow relaxation process, which is strongly correlated with the re-positioning of oxygen vacancies related trap charges, takes place in CCTO. The main trap charge relaxation process is thought to occur between the boundaries perpendicular and parallel to the external electric field, and the anisotropy of the defect dipoles provide the possibilities for trap charge repositioning which maybe the reason of the huge dielectric constant. [ABSTRACT FROM AUTHOR]

Two successive magnetocaloric effects consisting of inverse magnetocaloric effect around martensitic transition and negative magnetocaloric effect around magnetic transition of austenitic phase have been observed in Ni50Mn34In15Al alloy. Large inverse magnetic entropy change ΔSm ( ~ 21.3 J kg−1 K−1), small thermal and magnetic hysteresis of martensitic transition give rise of large net refrigerant capacity ( ~ 152.3 J kg−1) under a magnetic field of 50 kOe, which is comparable with that ( ~ 157.9 J kg−1) of second-order transition. The large combined magnetocaloric effects make the Ni50Mn34In15Al alloy as a promising candidate material for room temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

MicroRNAs are a class of small non-coding RNAs that play essential roles in cancer development and progression. Recent studies suggested that abnormal expression of miRNAs occurs frequently in non-small cell lung cancer (NSCLC) tissues compared to adjacent normal tissues. In this study, we investigated the expression and the biological roles of miR-106a in non-small cell lung cancer. Our results showed that miR-106a was up-regulated in NSCLC tissues and cell lines. Inhibition of miR-106a in NSCLC cells substantially inhibited cell proliferation, migration, and invasion. Phosphatase and tensin homolog (PTEN) was identified as a direct target of miR-106a, and over-expression of miR-106a suppressed PTEN by direct binding to its 3'-untranslated region (3'-UTR). Furthermore, the presence of miR-106a was inversely correlated with PTEN in NSCLC tissues. Overall, this study suggested that miR-106a inhibited the growth and metastasis of NSCLC cells by decreasing PTEN expression. These data provide novel insights with potential therapeutic applications for the treatment of NSCLC.

Introduction: Long non coding RNAs (lncRNAs) have emerged recently as major players in tumor biology and may be used for cancer diagnosis, prognosis, and potential therapeutic targets. The lncRNA HMlincRNA717, a newly identified lncRNA, was demonstrated to be down-regulated in gastric cancer. However, little is known about its role in non small cell lung cancer (NSCLC)., Methods: Expression of lncRNA HMlincRNA717 in tumor and their matched non-tumor tissues was determined by quantitative real-time PCR (qRT-PCR) in NSCLC patients. Then, we analyzed the potential relationship between lncRNA HMlincRNA717 expression levels in tumor tissues and clinicopathological features of NSCLC, and clinical outcome., Results: lncRNA HMlincRNA717 expression level was significantly decreased in NSCLC tissues in comparison to adjacent non-tumor tissues. It was also proved that HMlincRNA717 expression was to be associated with NSCLC histological grade, and lymph node metastasis. In addition, survival analysis proved that down-regulated HMlincRNA717 expression was associated with poor overall survival of NSCLC patients. Multivariate survival analysis also proved that HMlincRNA717 was an independent prognostic factor for NSCLC patients., Conclusions: The present study showed the down-regulation of HMlincRNA717 and its association with tumor progression in human NSCLC. It also provided that HMlincRNA717 expression was an independent prognostic factor for patients with NSCLC, which might be a potential prognostic biomarker and therapeutic target for NSCLC.

Self-assembled monolayer film of gold nanoparticles (55 nm) was formed at air-water interface by the driving force of wettability-shift of gold nanoparticles from hydrophilic property to hydrophobic property when encapsulated with 1-dodecanethiol. SEM image shows that the structure of the surface is nearly monolayer with closed arrays of uniform particle size when the film is transferred onto Si wafer. The substrate can be used for SERS substrate to realize semiquantitative analysis of melamine and the detection limit can reach l x 10(-9) g x L(-1). This SERS substrate is of wide application, not only for melamine but also for nonpolar molecule such as polycyclic aromatic hydrocarbons.

After solving the problems of synchronization of the measuring system and the avoidance of false trigger signal, the instantaneous emission spectrum of epoxypropane with an exposure time of 2 micros and a resolution of 0.2 nm was acquired from a side window of a shock tube at the very moment when the epoxypropane transformed from deflagration to detonation. The measuring system consists of an advanced intensified charge-coupled-device spectroscopic detector, a digital delay generator DG535, an explosion shock tube and optical fibers. The DDT process was monitored by pressure transducers. After correcting the intensity of the spectrum obtained, the background curve of the heat radiation intensity of the detonation was given immediately. The detonation temperature of 2 416 K for epoxypropane was derived from fitting the curve with Planck blackbody formula by least squares principle. The detonation temperature of epoxypropane can provide an experimental datum for analyzing the microscopic mechanism of DDT process.

After solving problems of weak light detection, the calibration of the spectral sensitivity of the measuring system, and the synchronization of the measuring system, instantaneous emission spectra of epoxypropane in the process of deflagration to detonation transition (DDT) with the exposure time of 2-8 micros and the resolution of 0. 2 nm were acquired from six different side windows of an explosion shock tube. Using the corrected spectral data, curves of the optical radiant intensity of main reaction products versus the DDT distance from the ignition point were obtained. These curves provided information about the evolution of the reaction and the products during the DDT process. Results indicate that the chemical reaction rate of the gaseous fuel and the corresponding concentrations of intermediate products increased gradually at the deflagration stage, but at the moment of deflagration to detonation transition, the reaction rate increased rapidly and the concentrations! of products increased sharply. Among these main products, concentration increments of molecule CO, and radicals CHO and OH were greater than other products, which means that CO, CHO and OH are the dominant species that affect the DDT process greatly.

After solving problems of the synchronization of the measuring system, the detection of weak light, and the avoidance of false trigger signal, the instantaneous emission spectra of epoxypropane in the process of deflagration to detonation transition (DDT) with the exposure time of 1-16 micros and the resolution of 0.2 nm were measured. The spectra were acquired from side windows of an explosion shock tube 0.1 m in inner diameter and 4.0 m in length. The measuring system is made up of an intensified spectroscopic detector ICCD, a SpectraPro-275 spectrograph, and a digital delay generator DG535. By analyzing the spectra obtained, the reaction products OH, CH, C2, C3, CO, CO2, CHO and CH2O were identified according to their characteristic electronic and vibrational bands, which indicates that these molecules and radicals were produced during the DDT process of epoxypropane. The determination of reaction products can provide experimental basis for analyzing and understanding the microscopic mechanism of DDT process.

Using ICCD spectral detection system, the absorbency of lycopene-carbon bisulfide solution with different concentration was measured, and the result shows that in a specified range the absorption rule of lycopene solution agrees with Lambert-Beer Law. Absorption spectral wavelength shifts were measured respectively when lycopene was dissolved in acetone, normal hexane, petroleum ether, benzene, ethyl acetate, and carbon bisulfide, and comparing to acetone, different red-shift appeared when lycopene was dissolved in benzene, ethyl acetate, and carbon bisulfide when water was added in lycopene-acetone solution, t he absorbency of lycopene dropped, the fine structure of absorption spectrum became indistinct, and a new absorption peak appeared in UV. The reason for these phenomena is that the solvent molecule had different effect on lycopene molecule when lycopene was dissolved in different solvent. Using fluorecence spectrophotometer, fluorescence spectra of lycopene in different concentrations were collected, and the results show that the fluorescence spectra of lycopene were mainly in 500-680 nm. When concentration was lower than 50 microg x mL(-1), the fluorescence intensity linearly increased with increasing concentration, and when concentration was higher than 60 microg x mL(-1), the fluorescence intensity dropped because of the interaction between lycopene molecules.

Objective: To study transcription, expression, and bioactivity of expressive protein of vascular endothelial growth factor 165 (VEGF(165)) gene, after bone marrow stromal cells (BMSCs) were transferred by VEGF(165) gene mediated by adenovirus vector ex vivo., Methods: BMSCs were Isolated and cultured by gradient centrifugation method. The cells cultured are transferred by recombinant adenovirus vector that carry VEGF(165) gene. Transcription and expression of VEGF(165) gene in BMSCs and secretion of VEGF protein in culture medium were measured by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot and enzyme linked immunosorbent assay (ELISA) methods. The activity of VEGF protein in culture media was detected by proliferation effects on vascular endothelial cells., Results: When Ad. VEGF(165) transferred into BMSCs, there was an effective transcription and expression. The expressed product in the media of transferred cells had highly biological activity on proliferation of rat aortic vascular endothelial cells (P < 0.01)., Conclusions: Adenovirus vector can be transferred into BMSCs efficiently and safely. Adenovirus mediated VEGF(165) gene transferred into BMSCs could express VEGF protein with highly biological activity, which provided foundation on BMSCs based gene therapy for ischemic disease.

Using an intensified CCD spectroscopic detector (Princeton Instruments, ICCD PI-Max 1024 RB) which can be gated in as little as 5 ns, the synchronization of the measuring system was controlled by a digital delay generator (Stanford Research Systems, DG535), the DG535 was triggered externally by a lab-made electrical pulse generator which transformed the optical trigger signal to an electrical signal, and the light signal from the end window of an explosion shock tube was delivered by an 1 mm in diameter plastic optical fiber to the entrance slit of the spectrometer (grating of 150 g x mm(-1) , central wavelength of 550 nm). The spectrum measurement of the epoxypropane in the process of deflagration to detonation transition (DDT) was then made. The instantaneous emission spectra of epoxypropane at different time of the DDT process with an exposure time of several microseconds were acquired. Results show that at the beginning of the DDT process, the emitted light was very weak and the line spectra of atoms were observed mainly; in the middle process of the DDT, the emitted light became strong and the spectra observed consisted of line spectra of atoms, band spectra of molecules plus continuous spectrum of the thermal radiation; when the detonation was formed, the emitted light got very strong, and the spectra acquired consisted of both line spectra of atoms and band spectra of molecules superimposed on the strong continuum of the thermal radiation.