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Lead zirconate titanate (PZT) thin films were coated on Pt/Ti/ SiO2/Si substrates by the sol-gel method and then crystallized by microwave annealing using a single-mode 2.45 GHz microwave irradiation system in the magnetic field. The crystalline phases and microstructures as well as the ferroelectric properties of the PZT films were investigated as a function of the elevated temperature generated by microwave irradiation, and the phase transition in the crystallization of the PZT thin films was discussed. X-ray diffraction analysis and transmission electron microscopic study indicated that the crystallization to the perovskite phase in the PZT films by microwave annealing started at 430°C, and mostly finished at 450°C for 30 min. The remanent polarization of the PZT films increased with the increasing annealing temperature, and the lowest temperature required to obtain perovskite PZT films with good ferroelectric properties in the microwave irradiation processing was 450°C, which is much lower than that in conventional thermal processing. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding a study which was conducted to analyze the potential function of c-Jun N-terminal kinase (JNK) signaling in lethal giant larvae (lgl) tumor development.

Green GaInN/GaN quantum well light-emitting diode (LED) wafers were grown on nanopatterned c-plane sapphire substrate by metal-organic vapor phase epitaxy. Without roughening the chip surface, such LEDs show triple the light output over structures on planar sapphire. By quantitative analysis the enhancement was attributed to both, enhanced generation efficiency and extraction. The spectral interference and emission patterns reveal a 58% enhanced light extraction while photoluminescence reveals a doubling of the internal quantum efficiency. The latter was attributed to a 44% lower threading dislocation density as observed in transmission electron microscopy. The partial light output power measured from the sapphire side of the unencapsulated nanopatterned substrate LED die reaches 5.2 mW at 525 nm at 100 mA compared to 1.8 mW in the reference LED. [ABSTRACT FROM AUTHOR]

We report the development of 480 nm cyan and 520 nm green light emitting diodes (LEDs) with a highly stable emission wavelength. The shift is less than 3 nm when the drive current density is changed from 0.1 to 38 A/cm2. LEDs have been obtained in GaInN-based homoepitaxy on nonpolar m-plane GaN bulk substrates. For increasing emission wavelength we find a large number of additional dislocations generated within the quantum wells (2×108 to ∼1010 cm2) and a decrease in the electroluminescence efficiency. This suggests that the strain induced generation of defects plays a significant role in the performance limitations. [ABSTRACT FROM AUTHOR]

We report the development of 520–540 nm green light emitting diodes (LEDs) grown along the nonpolar a axis of GaN. GaInN/GaN-based quantum well structures were grown in homoepitaxy on both, a-plane bulk GaN and a-plane GaN on r-plane sapphire. LEDs on GaN show higher, virtually dislocation-free crystalline quality and three times higher light output power when compared to those on r-plane sapphire. Both structures show a much smaller wavelength blue shift for increasing current density (<10 nm for 0.1 to 12.7 A/cm2) than conventional LEDs grown along the polar c axis. [ABSTRACT FROM AUTHOR]

ZnO:Al thin films with Al incorporation of 0-20 at.% were deposited through the sol-gel technique. Such a film undergoes a significant microstructure development, from columnar to granular structures and then nanorod arrays with increasing Al content. The important role of Al incorporation level in the microstructure evolution was determined using scanning electron microscopy, x-ray photoelectron spectroscopy and transmission electron microscopy. At low Al level, the transition from columnar to granular grains can be attributed to the coarsening barrier resulting from the introduction of Al into the matrix. However, oriented structures of ZnO nanorod arrays are formed at a high Al level. TEM investigation reveals that a nanorod with smooth morphology at the top and rough morphology at the bottom has a single-crystalline wurtzite structure, which is the aggregation of nanoparticles of a few nanometers in size formed through the orientation attachment mechanism followed by epitaxial growth on the aggregated particles. Finally, the physical properties of the ZnO films with different degrees of Al concentration are discussed. Such detailed microstructure studies may aid the understanding of the doping effect process on the growth of a film, which is essential to altering its physical or chemical properties. [ABSTRACT FROM AUTHOR]

Background and Aims: To compare the association of geriatric nutritional risk index (GNRI) and controlling nutritional status (CONUT) scores with malnutrition, and to study their association with clinical outcomes in older adult cancer patients., Methods: This retrospective analysis was conducted on 854 older adult cancer patients collected from 34 hospitals in 18 cities in China between June and September 2014. Anthropometric and hematological examination results at admission were collected, and subjective global assessment was used. Clinical outcomes, such as complications, length of hospital stays, and hospital costs, were recorded. Receiver operating characteristic curves were used to evaluate the accuracy of the two nutritional assessment tools for malnutrition. The association between GNRI and CONUT score and clinical outcomes was analyzed using the chi-square test, t-test, or rank sum test., Results: Among 854 patients with cancer, the prevalence of malnutrition was 42.7%. Compared with subjective global assessment, the GNRI had a significantly higher accuracy than the CONUT score in predicting malnutrition (area under the curve 0.704, 95% confidence interval, 0.658 - 0.750, P < 0.001). The GNRI was significantly associated with the occurrence of complications (χ2 = 4.985, P = 0.026), and low GNRI (≤98) was associated with a longer length of hospital stay (t = -2.179, P = 0.030)., Conclusions: The GNRI may be used to assess malnutrition in older adult cancer patients and can predict poor clinical outcomes in these patients., Competing Interests: The authors declare that they have no conflicts of interest.