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In a previous study, GaN‐based nanopillars are grown vertically on a multicrystalline Si substrate by inserting (In)GaN steering crystals. In addition, blue‐green and white light‐emitting diodes (LEDs) are prepared on this substrate for the first time using a double heterotype p–n junction. Herein, the emission‐color distribution characteristics of this type of LED are analyzed in depth, and a related luminescence principle is proposed. Each nanopillar plus an electrode is considered a nanopillar LED, and the emission color of each nanopillar LED is inferred. The indium distribution in the InGaN active region is predicted based on the luminous color and corresponding spectra. Simultaneously, the morphology of related materials, electrical properties of LEDs, and chromaticity coordinates of luminous colors are analyzed and discussed. [ABSTRACT FROM AUTHOR]

In our past research, Group-III nitride nanopillar crystals were grown vertically on the multi-crystalline silicon substrate and applied to surface-emitting LEDs. To discuss the further possibilities of this kind of LEDs, such as application in long-wavelength LEDs, Mg-doped GaN and InGaN as important parts of the LEDs were grown under various conditions. Different testing experiments were carried out on these GaN-related samples to clarify their surface morphologies and luminescence characteristics. It was confirmed that Mg was successfully doped into GaN grown on the multi-crystalline silicon substrate. InGaN with a wide range of In-contents was obtained by using the same substrate. It is believed that these materials can be applied to various optoelectronic devices, especially large-area light-emitting devices with emissions of more colors, by analyzing the various properties. [ABSTRACT FROM AUTHOR]

To clarify soil respiration (soil CO2 efflux, Rs) characteristics in a subtropical evergreen broad‐leaved natural forest in Yambaru, Okinawa, Japan, we examined spatiotemporal variation in Rs and its determining factors. We then compared yearly Rs with the value in other forests. The spatial variation in Rs (coefficient of variation [CV] = 38.9%) was not significantly related to temperature or soil water content but was evidently dependent on ground surface litter coverage. Rs was greater in summer (ca. 7–10 μmol m−2 s−1), and its seasonal variation was exponentially related to soil temperature (Q10 = 2.16). As a function of soil temperature, we estimated a yearly mean stand‐scale Rs of 5.17 μmol m−2 s−1, and a total carbon efflux from the soil of 1959 g C m−2 year−1 for 2014. Despite showing similar seasonal patterns as those in temporal forests, the Rs in this ecosystem is very high throughout the year, and the yearly value is much higher for natural mature forests. A mass balance approach suggests that the large amount of belowground carbon allocation of plants contributed to the high CO2 emissions from the soils. [ABSTRACT FROM AUTHOR]

Background: Previously, MDR1 T-129C polymorphism, encoding multidrug resistant transporter MDR1/P-glycoprotein, was reported to be predictive of poorly-differentiated colorectal adenocarcinomas. Here, VEGF T-1498C, C-634G and C-7T polymorphisms, encoding vascular endothelial growth factor (VEGF), were investigated in terms of their association with differentiation grade. Methods: VEGF genotypes were determined by TaqManR MGB probe based polymerase chain reaction and evaluated were confirmed by direct sequencing in 36 Japanese patients. Results: VEGF T-1498C, but not C-634G or C-7T, was predictive of poorly-differentiated ones, and thereby a poor prognosis (p = 0.064 for genotype, p = 0.037 for allele), and this effect can be explained by that on VEGF expression. Treatment of a colorectal adenocarcinoma cell line, HCT-15, with sodium butyrate, a typical differentiating agent, resulted in an increase of alkaline phosphatase activity and MDR1 mRNA expression, but in a decrease of VEGF mRNA expression. The transfection of VEGF small interfering RNA (siRNA) induced the expression of MDR1 mRNA to 288-332% of the control level, whereas MDR1 siRNA had no effect on VEGF mRNA expression. Conclusions: VEGF T-1498C polymorphism is also a candidate marker predictive of poorly-differentiated colorectal adenocarcinomas, but further investigations with a large number of patients should be addressed to draw a conclusion.

Dead organic matter (DOM), which consists of leaf litter, fine woody debris (FWD; <3 cm diameter), downed coarse woody debris (CWDlog), and standing or suspended coarse woody debris (CWDsnag), contributes to forest carbon cycling; however, few studies have considered effects of differences in DOM types on the stand‐scale estimates of carbon stocks of necromass and CO2 efflux (Rstand). This study investigated characteristics of necromass and Rstand in a subtropical forest in Okinawa Island, Japan, to quantify the effect of DOM type on total necromass, total Rstand, and estimate error of total necromass and Rstand. The CWDsnag accounted for the highest proportion (54%) of total necromass (1499.7 g C m−2), followed by CWDlog (24%), FWD (11%), and leaf litter (11%). Leaf litter accounted for the highest proportion (37%) of total Rstand (340.6 g C m−2 year−1), followed by CWDsnag (25%), CWDlog (20%), and FWD (17%). The CWDsnag was distributed locally with 173% coefficient of variation for necromass, which was twofold higher than those of leaf litter and FWD (72%–73%). The potential error in CWD accounted for 99% and 79% estimate error for total necromass and Rstand, respectively. For the estimates of CWDsnag and CWDlog necromass with the estimates error of <10% in this study area, sampling areas of ≥28,750 m2 and ≥2058–42,875 m2, respectively, were required. Our results showed that CWD considerably contributed to stand‐scale carbon stocks and efflux among aboveground DOM in this forest, resulting in a major source of errors in the stand‐scale estimates. [ABSTRACT FROM AUTHOR]

Fine root decomposition, mortality, and production are fundamental components of belowground carbon dynamics in mangrove ecosystems. Mangroves are highly productive ecosystems with huge carbon stocks; however, information on the dynamics of submerged fine roots in mangrove soils is limited. To estimate fine root production in several sites of mangrove communities on Pohnpei Island, Micronesia, we estimated continuous inflows using a simple mass balance model to combine ingrowth core and litterbag experimental results. According to our findings, previously reported mangrove fine root production values were severely underestimated because the fine root decomposition process was disregarded during the experimental period. We estimated that annual fine root production up to 0.3 m in depth ranged from 13.8 (Bruguiera gymnorrhiza in a landward plot) to 56.3 Mg ha−1 year−1 (B. gymnorrhiza in a seaward plot). However, comparing the fine root production with respect to the unit of stem cross‐section area increase in the sample tree, the fine root production of Rhizophora spp. was greater than that of other species. The annual fine root mortality and decomposition to annual fine root production was 70%–105% and 11%–52% of annual production, respectively. The annual fine root production estimated here was much higher than that previously reported. These findings begin to quantify the contribution and importance of highly productive mangrove fine roots for carbon sequestration in blue carbon ecosystems. Moreover, this study provides new insights into the organic carbon dynamics in mangrove soils with mangrove vegetation succession. [ABSTRACT FROM AUTHOR]

Strong Langmuir turbulence fields driven by an intense relativistic beam were probed using a weak electron beam after the intense beam passed through a plasma, Persistence of the strong Langmuir turbulence state was proved by observing broadening of the profile of the probe beam after it traversed the plasma column. Index Terms--Caviton, electron beam probing, intense relativistic electron beam (IREB), strong Langmuir turbulence, wake fields.