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The single layer and multilayer undoped light-emitting devices were fabricated using a new soluble phenothiazine-based derivative, poly(3,7- N -octyl phenothiozinyl terephthalylidene) (POPTP). Through the optimization of device structures, the multilayer device has a maximum luminance of 1203 cd/m 2 at the bias voltage of 9.3 V, using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) as a hole-blocking layer and tris-(8-hydroxyquinoline)aluminium (Alq 3 ) as a electron-injection/transporting layer. The Commision International de L’Eclairage (CIE) coordinates stabilized at ( x , y ) = (0.46, 0.53) at various bias voltages. Additionally, the dominant wavelength ( λ D ) of around 575 nm and the color purity of approximately 100% indicated a pure yellow emission property. Therefore, POPTP is a stable candidate material with a pure yellow emission for the undoped organic light-emitting diodes (OLEDs).

In 2 TiO 5 is the only ternary oxide in the In–Ti–O phase diagram. It was prepared by high temperature solid state reaction in this work and verified to be pure with high crystallinity by Le Bail fitting on the powder X-ray diffraction (XRD) pattern. Scanning electron microscopy show that the micrometer particles of In 2 TiO 5 was composed of submicron crystallites. UV–vis diffused reflectance spectra suggested a wide bandgap of 3.55 eV, which is consistent with the theoretical calculations. The bottom of the conduction band is composed of both In 6s and Ti 3d orbitals, however the low density of the states lead to a low density of the charge carriers excited by UV irradiation. Thus the photocatalytic H 2 production rate of In 2 TiO 5 is only 3.6 μmol/h/g in 20 vol% methanol aqueous solution. With the assistance of Ru- and Pt-cocatalyst, the activity is significantly increased and the optimal H 2 evolution rate is 35.7 μmol/h/g when loading 1 wt% Ru and 1 wt% Pt, simultaneously. All the catalysts recovered after the photocatalytic reactions show no degradation according to powder XRD.

The Forkhead box O (FOXO) protein family is predominantly involved in apoptosis, oxidative stress, DNA damage/repair, tumor angiogenesis, glycometabolism, regulating life span and other important biological processes. Its activity is affected by a variety of posttranslational modifications (PTMs), including phosphorylation, acetylation, ubiquitination, methylation and glycosylation. When cells are subjected to different environments, the corresponding PTMs act on the FOXO protein family, to change transcriptional activity or subcellular localization, and the expression of downstream target genes, will ultimately affect the biological behavior of the cells. In this review, we will discuss the biological characteristics of FOXO protein PTMs.

Two novel polymers PQP(poly(3, 7-N-octyl phenothiozinyl cyanoterephthalylidene)) and PQM (poly(3, 7-N-octyl phenothiozinyl cyanoisophthalylidene)) containing phenothiazine were synthesized for application in red and orange light-emitting diodes. The synthesized polymers were characterized using UV-visible, photoluminescence and electroluminescence (EL) spectroscopy. The single-layer EL devices of indium tin oxide(ITO)/PQP(or PQM)/Mg : Ag and multi-layer devices of ITO/PQP(or PQM): N, N'-diphenyl-N, N'-bis(3-methylphenyl) -[1, 1'-biphenyl]-4, 4' -diamine(TPD) (44 nm)/2, 9-dimethyl-4, 7-diphenyl -1, 10-phenanthroline (BCP, 5 nm)/tris(8-hydroxyquinolinato) aluminium(AlQ3, 20 nm)/Mg : Ag were fabricated. The EL spectra from the devices based on PQP peaked at the wavelength of 664 nm and covered red and infrared regions. The maximal brightness was measured to be about 60 cd m−2 at the applied voltage of 17 V. The devices based on PQM gave bright orange light-emission peaking at 608 nm and the maximal luminance was 150 cd m−2 at the applied voltage of 14 V.

Optically excited organic semiconductor distributed feedback (DFB) lasers enable efficient lasing in the visible spectrum. Here, we report on the rapid and parallel fabrication of DFB lasers via transferring a nanograting structure from a flexible mold onto an unstructured film of the organic gain material. This geometrically well-defined structure allows for a systematic investigation of the laser threshold behavior. The laser thresholds for these devices show a strong dependence on the pump spot diameter. This experimental finding is in good qualitative agreement with calculations based on coupled-wave theory. With further investigations on various DFB laser geometries prepared by different routes and based on different organic gain materials, we found that these findings are quite general. This is important for the comparison of threshold values of various devices characterized under different excitation areas.

Electromembrane extraction (EME) as a novel sample preparation technique was firstly applied for the purification and enrichment of four polyamines mainly present in saliva samples. These four target analytes, putrescine, cadaverine, spermidine, and spermine, were directly determined by CZE with capacitively coupled contactless conductivity detection (CZE-C 4 D) after EME procedure. Several factors affecting extraction efficiency, electrophoretic separation, and detection were investigated. Under the optimum conditions, four polyamines were baseline separated within 22 min, exhibiting a linear calibration over three orders of magnitude ( r >0.999); the highest enrichment factor could reach 106-fold (for spermidine), and the LODs were in the range of 1.4–7.0 ng mL −1 . The proposed EME/CZE-C 4 D method has been successfully applied to analyze human saliva samples with recoveries in the range of 78–97%.

Summary form only given. Organic semiconductor distributed feedback (DFB) lasers are of particular interest as tunable visible laser light sources. They are becoming promising candidates as excitation sources integrated in photonic lab-on-a-chip (LOC) or other sensing systems [1-3]. For bringing those to market, the established device fabrication methods and large-area thin film deposition may not fulfil the functionality and flexibility required by miniaturised LOC applications. We demonstrate two novel inexpensive fabrication methods to implement spatially defined organic semiconductor DFB lasers with a high yield and without negative influences on surrounding microstructures, e.g., passive photonic components. We applied nanograting transfer as a convenient method to fabricate localized organic small molecule DFB lasers. The fabrication process of the DFB laser device is depicted in Figs. 1(a) and (b). The cyclic olefin copolymer (COC) mold with a small molecule layer on top was pressed onto the unstructured plane active layer under high pressure. The previously deposited layer was subsequently detached from the mold and transferred to the plane substrate [4]. A scanning electron microscope (SEM) image of the grating on the final device is shown in Fig. 1(c). Fig. 1(d) shows the laser emission and laser threshold of the fabricated device. For solution processing of localized organic polymer DFB lasers, we used ink-jet printing to deposit the active conjugated polymer solutions onto the predefined DFB grating regions [5]. Utilizing a mixture of high-boiling and low-boiling solvents for dissolving the polymer, the ink-jet printed film profile was optimized, thus creating uniformly emitting organic lasers. With precise control of jetting duration, frequency, slew rate and firing voltage, the spatial accuracy of printing and thus the laser emission from the device can be improved. We demonstrate the accurate lateral positioning of ink-jet printed laser pixels on a polymer substrate with 500 μm × 500 μm grating fields (see Fig. 2(a), (b) and (c)).

Various physiological processes and behaviors show a circadian rhythm of approximately 24 h, which is crucial in coordinating internal metabolic processes and environmental signals. Post-translational modifications play an important role in regulating circadian core proteins. In this study, we demonstrated that BMAL1 was modified with an O-linked β-N-acetylglucosamine (O-GlcNAc), which stabilized BMAL1 and enhanced its transcriptional activity. Conversely, inhibition of O-GlcNAcylation resulted in inhibition of circadian rhythms of clock gene expression. Because O-GlcNAcylation is sensitive to the glucose level, such a modification may provide a new mechanism connecting metabolism with circadian rhythms.

Damage-free transfer of nanogratings as waveguide mode extraction elements onto the top of top-emission organic light-emitting devices(OLEDs) was realized with the assistance of cyclic olefin copolymer molds. Photoluminescence and electroluminescence measurements together with transfer matrix calculations were used to identify the extracted waveguide modes. The presented one-step, wet-free, and etchless nanotransfer approach can avoid damage on the top-emission OLEDstructure and does not adversely affect the OLED performance. It offers the possibility for the independent optimization of OLEDfabrication and nanofabrication, and has potential applications in organic optoelectronic devices, especially top-emission OLEDs.

A stable self nano-aggregated bathocuproine film was fabricated and introduced atop of conventional organic light emitting diode for enhancing top emission leading to 2.7 times enhancement on top emission due to scattering surface plasmon energy.

Samples of sub-surface water, suspended particulate matter (SPM) and surface sediments collected from Daya Bay, China have been analysed for 12 polychlorinated biphenyl (PCB) congeners and 18 organochlorine insecticides, using gas chromatography electron capture detection. Total PCB levels varied from 91.1 to 1355.3 ng l(-1) in water and from 0.85 to 27.37 ng g(-1) dry weight in sediments. The levels of total organochlorine insecticides were in the range 143.3-5104.8 ng l(-1) in water and 2.43-86.25 ng g(-1) dry weight in sediment. None of the target compounds were detected in SPM. The levels of total hexachlorocyclohexanes in water varied from 35.5 to 1228.6 ng l(-1), whilst in sediments they ranged from 0.32 to 4.16 ng g(-1) dry weight. For the sum of dichlorodiphenyltrichloroethanes (DDTs), their levels were in the range 26.8-975.9 ng l(-1) in water, and 0.14-20.27 ng g(-1) dry weight in sediments. The distribution profiles of these contaminants in water and sediments suggest that there are a number of sources contributing to total contaminant burden in the bay, including soil runoffs, wastewater discharges, sewage outfalls and shipping activities. Ratios of DDT/(DDE + DDD) in the water and sediments indicate recent inputs of such chemicals into the bay. The results, therefore, provide important information on the current contamination status of a key aquacultural area in China, and point to the need for urgent actions to stop the use of persistent agrochemicals such as DDT and lindane. (C) 2001 Elsevier Science Ltd. All rights reserved.

Using the pulsed laser deposition method, we have prepared epitaxial Pr0.5Ca0.5Ba2Cu3O7−y (PCBCO) thin films with TC(R=0)=35.4K. Through in situ annealing in different oxygen pressure at 350°, the thin films have various oxygen contents. We found that the optimum condition for the highest TC is annealing in oxygen pressures of 0.2–0.8 atm. In contrast, the thin films annealed in 1 atm of oxygen have lower TC, although they show smaller resistivities. The relationship between TC and Hall coefficients of RH have been measured for the epitaxial films with different oxygen contents. The Hall measurements show that the thin films with higher TC(R = 0) have larger Hall concentration (1/HH). We found that the 1/RH doesn't have linear relationship with temperature. Anomalous result has also been obtained that the fully oxygenated PCBCO films have smaller resistivity (ϱ), but lower TC and lower 1/RH.

Pr 0.5 Ca 0.5 (Ba 1-x Sr x ) 2 Cu 3 O 7-y (PCBSCO)(x=0, 0.1, 0.2, 0.3) epitaxial thin films have been prepared by the pulsed laser deposition method. By 10% Sr substitution for Ba, the T C (R=0) of the PCBSCO films increases from 35K(x=0) to 39K(x=0.1). The resistance measurments show that PCBSCO (x=0.1) films have lower resistivity (p) compared with that of PCBSCO (x=0) films. Increasing the substitution concentration x further to 0.2 and 0.3, the resistivities of the films begin to increase and the superconductivity is gradually suppressed. The effects of the oxygen content on the superconductivity of PCBSCO have also been studied.

Enhanced photoluminescence was found in tris-8-hydroxyquinoline aluminum deposited onto nanotextured silver films with porous alumina substrates. The surface-enhanced Raman signals and shortened lifetimes suggested the presence of enhanced local electromagnetic field due to the plasmon resonance of nanotextured silver films. The photoluminescence enhancement was attributed to the increase in absorption and quantum yield. The authors analyzed the increase in quantum yield and found that the highest quantum yield was enhanced by 2.3 times compared with the samples based on flat Ag film with the same thickness. The enhancement of quantum yield has potential applications in electro-optic devices.

Polysulfone (PSF)-Fe3O4 composite membranes were prepared by the phase-inversion process and their polysaccharide separation mechanism was explored using chondroitin sulfate (CS) and dextran. The mechanism was analyzed from constraints on the magnetic field and geometric deformation. It was found that variations in dextran rejection from 58% to 46% were mainly influenced by the geometric deformation of the composite membrane, while the magnetic field had a significant influence on variations in CS rejection from 82% to 35%. The results indicate that it is possible to continuously separate different types of polysaccharide with a composite membrane by adjusting the external magnetic field.

Ultrafast thulium-doped fiber lasers emitting in the 2 μm wavelength region have recently attracted a significant amount of attention regarding applications in material processing, life sciences, as well as in fundamental science, e.g. high harmonic generation, particle acceleration, mid-IR generation [1,2]. In addition to the application-relevant emission wavelength, Tm-doped silica fibers possess many interesting characteristics, such as a broad gain bandwidth spanning from 1700 nm to 2100 nm and more than 70% slope efficiency by exploiting cross-relaxation processes [3]. Furthermore, the longer operation wavelength reduces the impact of detrimental nonlinear effects in fiber lasers, and allows for a larger mode field area with diffraction-limited beam quality as compared to the well-established ytterbium-doped fiber laser systems [4].

We present HHG results obtained with thulium-doped fiber lasers. It is the first time that a photon energy cut-off close to 400 eV has been demonstrated using this highly scalable laser technology.

We experimentally analyze the average-power-scaling capabilities of ultrafast, thulium-doped fiber amplifiers. It has been theoretically predicted that thulium-doped fiber laser systems, with an emission wavelength around 2 µm, should be able to withstand much higher heat-loads than their Yb-doped counterparts before the onset of transverse mode instability (TMI) is observed. In this work we experimentally verify this theoretical prediction by operating thulium doped fibers at very high heat-load. In separate experiments we analyze the performance of two different large-core, thulium-doped fiber amplifiers. The first experiment aims at operating a short, very-large core, thulium-doped fiber amplifier at extreme heat-load levels of more than 300 W/m. Even at this extreme heat-load level, the onset of TMI is not observed. The second experiment maximizes the extractable average-output power from a large-core, thulium-doped, fiber amplifier. We have achieved a pump-limited average output power of 1.15 kW without the onset of TMI. However, during a longer period of operation at this power level the amplifier performance steadily degraded and TMI could be observed for average powers in excess of 847 W thereafter. This is the first time, to the best of our knowledge, that TMI has been reported in a thulium-doped fiber amplifier.