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In this work, blue-green InGaN/GaN multiple quantum wells (MQWs) were grown on SiC substrates by metal-organic chemical vapor deposition. The influence of growth pressure on the structural and optical properties and surface morphology of the MQWs was studied. The photoluminescence measurement results indicate that the indium content in the MQWs nearly doubles when the growth pressure increases from 100 to 400 mbar, and the MQWs grown at different pressures exhibit distinct temperature-dependent optical behaviors. Meanwhile, the growth pressure also influences the structural characteristics of the MQWs significantly. Besides, with changing the growth pressure, the surface root-mean-square roughness, V-shaped pits density, V-shaped pits size, and localization state density of the MQWs were changed accordingly. [Display omitted] • The influence of different growth pressures on the structural characteristics of multiple quantum wells is investigated. • The luminescence properties of localization states of quantum wells are studied. • The formation of V-shaped pits is suppressed by increasing the growth pressure. • The incorporation efficiency of indium is improved at higher growth pressure. [ABSTRACT FROM AUTHOR]

The distribution characteristics of nanoparticles associated with cells are crucial to many applications, including magnetic hyperthermia, drug carriers, etc. To clarify the locations when nanoparticles enter the in vivo environments is a necessity. In this work, superparamagnetic iron oxide nanoparticles modified with polyethylene glycol (PEG-SPIONs) were prepared by high temperature thermal decomposition method, and then stereotaxic injections of PEG-SPIONs into the substantia nigra of Sprague-Dawley rats were performed. The distribution of nanoparticles in rat brain was observed by inductively coupled plasma emission spectrometer (ICP-OES) and transmission electron microscopy (TEM). It was found that the iron contents were higher in the olfactory bulb, temporal lobe, prefrontal cortex and thalamus after the injection of PEG-SPIONs for 24 h and 7 days, PEG-SPIONs were mostly distributed around the axonal membrane and dendritic membrane, and a small amount were distributed near the myelin membrane and mitochondrial membrane, which can be ascribed to the nature of PEG, the hydration size and Zeta potential of PEG-SPIONs. Along with their magnetocaloric effect the PEG-SPIONs have potential to act on the ion channels on the cell membrane under an alternating current magnetic field. • The surface of SPIONs was modified with polyethylene glycol (PEG-SPIONs). • PEG-SPIONs had good biocompatibility and hydrophilicity. • The PEG-SPIONs showed good magnetocaloric effect. • PEG-SPIONs tended to be adsorbed on the cell membranes in rat brains. • PEG-SPIONs have potential to act on the cell membrane ion channels in rats. [ABSTRACT FROM AUTHOR]

To examine the temporal variation of macrobenthic community zonation over nearly 60 years and the effects of latitude and depth in the southern Yellow Sea and East China Sea, a total of 1386 box-corer samples from four large spatial scale studies during 1958–1959, 2000–2004, 2011–2013 and 2014–2016 period, respectively, were compiled. A total of 26, 14, 13 and 18 communities were identified, respectively during the four periods with the same analytical method. The Yellow Sea Cold Water Mass (YSCWM) community, restricted to the 34°N latitude in the south and 50 m isobaths in the west, varied little in its spatial pattern over nearly 60 years, while other communities did not. The representative species in the YSCWM community changed from the polychaetes to the brittle stars during 1958–2016. However, in other large spatial scale communities except the YSCWM community, the representative species changed from the echinoderms, nemerteans or crustaceans to the polychaetes. For the revisited locations across studies, significant temporal and spatial variations in community structure at both species and family levels were detected. Macrobenthic species with high consecutive contributions to the community similarity were significantly influenced by latitude, depth, temperature and salinity, among which latitude and depth were the first two most significant environmental variables. Species diversity increased from 32 to 37°N during 1958–1959, but decreased during 2014–2016. It seems that the latitude of 32°N is an ecological barrier for macrobenthic community and diversity, but its effects weakened from 1958 to 2016. Species diversity roughly showed a first increasing then decreasing trend with the increase of the water depth in the southern Yellow Sea and East China Sea. Unlabelled Image • Spatial patterns of most macrobenthic communities varied a lot over 60 years. • The YSCWM community was invariable in spatial pattern, but not in species composition. • Revisited locations showed significant temporal variation in community structure. • Latitude and depth significantly influence the macrobenthic diversity and abundance. • Ecological effects of 32°N latitude weakened for macrobenthos from 1958 to 2016. [ABSTRACT FROM AUTHOR]

Recent reports have shown that intracellular, (super)paramagnetic ferritin nanoparticles can gate TRPV1, a non-selective cation channel, in a magnetic field. Here, we report the effects of differing field strength and frequency as well as chemical inhibitors on channel gating using a Ca2+-sensitive promoter to express a secreted embryonic alkaline phosphatase (SEAP) reporter. Exposure of TRPV1-ferritin-expressing HEK-293T cells at 30 °C to an alternating magnetic field of 501 kHz and 27.1 mT significantly increased SEAP secretion by ~ 82% relative to control cells, with lesser effects at other field strengths and frequencies. Between 30–32 °C, SEAP production was strongly potentiated 3.3-fold by the addition of the TRPV1 agonist capsaicin. This potentiation was eliminated by the competitive antagonist AMG-21629, the NADPH oxidase assembly inhibitor apocynin, and the reactive oxygen species (ROS) scavenger N-acetylcysteine, suggesting that ROS contributes to magnetogenetic TRPV1 activation. These results provide a rational basis to address the heretofore unknown mechanism of magnetogenetics. [ABSTRACT FROM AUTHOR]

β gallium oxide (β-Ga 2 O 3) homoepitaxy films were grown on (2 ‾ 01) β-Ga 2 O 3 substrates by metal organic chemical vapor deposition (MOCVD). The effect of growth temperature on the crystalline quality was measured and systematically analyzed. The results showed the growth temperature played an important role in crystalline quality of β-Ga 2 O 3. The optimized single crystalline β-Ga 2 O 3 film was grown at 750 °C, and the full width at half maximum (FWHM) of X-ray diffraction (XRD) rocking curve was 21.6 arcsec, smaller than that of the β-Ga 2 O 3 substrate (26.3 arcsec). The film exhibited a greatly smooth surface and the root-mean-square (RMS) roughness was 0.68 nm. And the arrangement of atoms inside the film was in good accordance with lattice constants of β-Ga 2 O 3. In addition, the effect of the band structure on the luminescent properties of β-Ga 2 O 3 was discussed. • The crystalline quality of the optimized film was superior to that of the substrate. • Atomic arrangement inside the β-Ga 2 O 3 films was displayed. • The effect of band structure on the luminescent properties of β-Ga 2 O 3 was discussed. [ABSTRACT FROM AUTHOR]

The light-emitting diode of p-ZnO/n-GaAs heterojunction was grown by metal-organic chemical vapor deposition. The p-ZnO films have been formed by the doping As atoms which diffuse into ZnO film from GaAs substrate. The p-type behavior of As-doped ZnO films based on As-doped p-ZnO/n-GaAs, p-ZnO/p-GaAs heterojunction was studied by carrying out I-V measurements and x-ray photoelectron spectroscopy. The I-V characteristic of p-ZnO/n-GaAs heterojunction showed characteristic of rectifying diode and visual-infrared electroluminescence emission under forward current injection at room temperature. The I-V of the heterounction had a threshold voltage of ∼2.5 V. [ABSTRACT FROM AUTHOR]

Perovskite light emitting diodes (PeLEDs) have attracted massive research interest in recent years. In order to obtain better luminescent properties, most attention is paid to the emitting layer perovskite materials. Actually, the other layers such as the transport layers should also be optimized. We proposed the optimization of hole transport layer NiO materials by magnetron sputtering. Effects of RF power, sputtering pressure and sputtering argon-oxygen ratio on surface morphology and electrical properties of NiO film were studied. Sputtering power, pressure and Ar/O 2 were set at 90 W, 25 mTorr and 10/40 over the past parameters to optimize the NiO film in our previous ZnO/CsPbBr 3 /NiO structured all inorganic perovskite LED. SEM, PL, XRD measurements were conducted to characterize the CsPbBr 3 having good morphologies, light emitting characteristics, and crystal quality. PeLEDs with and without the optimized hole transport layer NiO were compared. The EL results show that the optimized PeLED has much better electroluminescence characteristics than the one without optimization. Our work demonstrated a possible way to improve the luminescence properties of the PeLED. [ABSTRACT FROM AUTHOR]

This study examined the planting density tolerance, grain yield improvement potential, and mechanisms of high-yielding spring maize varieties under increasing planting density and subsoiling. We planted two high-yielding spring maize varieties with a high or low tolerance to high planting densities (LM33 and XD20, respectively) at five different densities (D1: 60,000 plants ha−1, D2: 75,000 plants ha−1, D3: 90,000 plants ha−1, D4: 105,000 plants ha−1, and D5: 120,000 plants ha−1) using two tillage methods (35-cm subsoiling and 15-cm traditional rotary tillage). The response characteristics used to compare the performance of the two maize varieties under different planting densities and tillage methods included root characteristics, canopy physiology, yield, and yield components. The results show that: (1) Under rotary tillage, with the increase of planting density from 75,000 plants ha−1 to 90,000 plants ha−1, yields of high-yielding spring maize varieties improved. However, when the planting densities were beyond 90,000 plants ha−1, the yields stopped increase, or even decrease. Subsoiling increased the planting density by 15,000 plants ha−1, enhanced the highest yield by 1080 kg ha−1–1940 kg ha−1, and raised the yield gain by 11.17–30.72%. (2) Under rotary tillage, the functional indexes of the roots and canopy of high-yielding spring maize decreased as planting density increased, and the largest reductions of root dry weight, leaf area index (LAI) of post-anthesis, light transmission percentage (LTP) of ear leaves, bottom leaves LTP, and dry matter accumulation all occurred between D2 and D4. The largest decline of high tolerance variety emerged between D3 and D5, and the extent was smaller than the low tolerance variety. (3) Compared with rotary tillage, subsoiling reduced the extent declines in root dry weight, root length, and root surface area; delayed the attenuation of LAI and the relative chlorophyll content (SPAD) determined in leaves; and improved the LTP of ear layers and bottom layer during the late growth stage. The post-anthesis populations dry matter accumulation of XD20 and LM33 increased by 7.07% and 13.18%, respectively. In addition, subsoiling significantly increased the number of kernels/spike and 1000-grain weight as the planting density increased. Meanwhile, the planting densities at which dry root weight, population LAI, ear leaf LTP, bottom leaf LTP, and dry matter accumulation arose the largest reductions was raised to 15,000 plants ha−1. The effects of subsoiling in the high density-tolerant variety were more pronounced than the low density-tolerant variety. [ABSTRACT FROM AUTHOR]

Vertically aligned ZnO nanowall networks were grown on p-GaN/sapphire substrates by metal-organic chemical vapor deposition, and further heterojunction light-emitting diodes based on n-ZnO/p-GaN were fabricated. Highly efficient ultraviolet-blue emission was observed from the diode under forward bias, and it operated continuously for 8.5 h with decay of only 8.08% under a continuous current of 12 mA. The diode exhibited low emission onset and good stability. In addition, temperature-dependent electroluminescence and current-voltage behaviors of the diode were investigated to examine the thermal effects on light output power, spectral line shift, and temperature sensitivity of the resulting voltage. [ABSTRACT FROM AUTHOR]

Vertical conducting light-emitting diodes based on p-ZnO/n-GaN structure were fabricated on conductive n-SiC(6H) substrates. The p-ZnO:As films were prepared by arsenic out-diffusion from a sandwiched GaAs interlayer on a GaN/SiC template, and the AsZn-2VZn complex was considered to be the most probable defect contributing to the p-type conductivity of the ZnO:As films. Under forward bias, an intense ultraviolet emission at ∼384 nm from the ZnO side was observed. The electroluminescence performance of the diode was remarkable in terms of its low emission onset and high-purity ultraviolet emission. Additionally, the unencapsulated diode showed good stability over a duration of 2 months. [ABSTRACT FROM AUTHOR]

A correction to the article "Oxidant-induced apoptosis is mediated by oxidation of the actin-regulatory protein cofilin" that was published in 2009 is presented.