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We have demonstrated non-polar GaN power diodes (Schottky barrier diode and p–n junction diode) on foreign substrates featuring the true-lateral p–n and metal–semiconductor junctions. The diodes were fabricated on GaN islands laterally overgrown on the mask-patterned sapphire and Si substrates by metalorganic vapor phase epitaxy. The anode and cathode were formed on the opposed a-plane sidewalls of the island, making the device architecture essentially like the 90° rotation of the desired true-vertical power diodes. The ideality factor of the Schottky barrier diode remained 1.0 (from 1.00 to 1.05) over 7 decades in current. Specifically, a high critical electric field of 3.3 MV/cm was demonstrated on the p–n junction diode with avalanche capability. These performances reveal a strong potential of non-polar GaN with the true-lateral junctions for high power applications.

Herein, we investigate micro-light-emitting diodes (μLEDs) ranging in size from 160 × 160 to 10 × 10 μm2 and report that the differences in the behavior of InGaN-based blue (∼460 nm) and red (∼600 nm) μLEDs are related to carrier localization. The external quantum efficiency (EQE) of blue μLEDs decreases with size regardless of sidewall conditions, whereas that of red μLEDs is insignificant due to carrier localization. Atomic probe tomography examination of 30%, 15%, and 7.5% indium-concentrated InGaN layers used in red μLEDs shows that higher indium concentrations result in greater indium fluctuations, which promote carrier localization and thus shorten the diffusion length of carriers. Finally, by observing the peak wavelength of electroluminescence and the current density at peak EQE for both blue and red μLEDs, we find that radiative recombination rate in μLEDs is likely to be chip size dependent. [ABSTRACT FROM AUTHOR]

The production of germ cells in vitro would open important new avenues for stem biology and human medicine, but the mechanisms of germ cell differentiation are not well understood. The chicken, as a great model for embryology and development, was used in this study to help us explore its regulatory mechanisms. In this study, we reported a comprehensive genome-wide DNA methylation landscape in chicken germ cells, and transcriptomic dynamics was also presented. By uncovering DNA methylation patterns on individual genes, some genes accurately modulated by DNA methylation were found to be associated with cancers and virus infection, e.g., AKT1 and CTNNB1. Chicken-unique markers were also discovered for identifying male germ cells. Importantly, integrated epigenetic mechanisms were explored during male germ cell differentiation, which provides deep insight into the epigenetic processes associated with male germ cell differentiation and possibly improves treatment options to male infertility in animals and humans.

In order to get blueberries goes on sale in advance and obtain greater economic benefits, southern blueberries were moved to an intelligent greenhouse with controllable environment for experimental production. The early maturing production control technology of southern blueberry intelligent greenhouse was explored and studied. First, a detailed and comprehensive investigation and summary were conducted on the production factors of blueberry soilless cultivation, such as the production characteristics of various blueberry varieties, the pH and composition of the substrate, the key points of water and fertilizer irrigation, and the scope of the microenvironment climate. Then, the existing Venlo-type greenhouse was deployed for blueberry production, and the geography, climate and internal structural conditions of the greenhouse were briefly described, and the greenhouse blueberry full-cycle control goal was planned. Finally, the production control system was designed and implemented based on the Internet of Things technology, and the overall framework of the software layer, the hardware layer and the cloud were introduced. Based on multi-factor coordinated control model of greenhouse environment, according to the characteristics of blueberry growth environment, a set of blueberry greenhouse multi-factor coordinated control algorithms were proposed and used for environmental regulation. The experimental greenhouse is located in the southeast of Huaqiao Town, Kunshan city, Suzhou city, Jiangsu province. It has been verified that the overall control system has a significant effect, and the first wave of fruits was harvested in early May 2021, making the southern variety of blueberry enter the fruit picking period nearly one month earlier. Compared with the blueberry plants without cold storage, the yields per plant of "Star" "Emerald" "Lanmei No. 1", and "Coast" after cold storage increased by 51.5%, 85.5%, 43.8%, and 94.7%, respectively, and the weight of each fruit was increased 10.9%, 7.2%, 2.6%, and 5.3%, respectively. Experiments proved that the use of multi-factor coordinated control algorithms for regulation can increase the yield and quality of blueberries and achieve significant economic benefits and provide a demonstration for the industrialization of blueberry plants in southern greenhouses to promote early maturity production and management.

Track beam is an important structural component in maglev transportation. The analysis of its structural performance is quite critical, especially for the coupled dynamic analysis under the action of high-speed moving train, which is directly related to the operation safety and stability of the train. The dynamic coupling of the 600 km/h ultra-high-speed maglev track beam was studied, the train model was based on 5 rigid bodies and 30 degrees of freedom system, and the spatial coupling analysis model of the maglev track beam was established by using the Timoshenko beam element model with shear effect considered. For the specific implementation of the coupling analysis in the cross platform framework, the multi-body dynamics software Simpack, the large-scale finite element software ANSYS and the visual simulation tool MATLAB/Simulink modeling method were used, and the PID controller was introduced to actively control the whole suspension control system. The whole coupling system was divided into the main vehicle master system, the controller subsystem, and the track beam-pier subsystem. Besides, a coupled vibration model of maglev vehicle-controller-track beam was established. Taking a simply supported bridge with a span of 24.768 m as an example, the vertical dynamic response of the following cars and track beams of ultra-high-speed maglev vehicle running was studied, and the dynamic performance of the control system was evaluated. In addition, the change law of multi-parameter dynamic response considering the influence of bridge pier parametric vibration is given, which will provide technical support for the construction of ultra-high-speed maglev projects in the future.

Based on drilling cores, logging, and 3D seismic data, combined with deepwater turbidity and seismic sedimentology theories, this study investigates the seismic response characteristics, development and evolution processes, depositional models, reservoir quality, and main controlling factors of the Miocene deepwater turbidity deposits in the Niger Delta Basin. The results show that the target layer in the study area can be divided into 2 second-order sequences(Sql and Sq2) and 6 third-order sequences. Five turbidite units including turbidite channel, levee, overbank sediment, crevasse splay and terminal fan, can be identified. The turbidite system deposited in the lowstand period of the Miocene when sea level was strongly declining, gradually transitioning from the deep sea basin to the lower part of the continental slope. It successively developed turbidite channel end fans, semi restricted to non restricted high curvature turbidite channels, and restricted turbidite channel-levee complex sediments. All reservoirs are of medium porosity and medium high permeability physical characteristics, but the sand body size, sand and mudstone ratio, and lateral continuity gradually deteriorate overall. In the Miocene, the global ice age climate, strong tectonic uplift, and continuous sea level decline generally controlled the strength of turbidity currents and changes in sedimentary characteristics. Local ancient landforms further affect the distribution, scale, and morphology of turbidite sedimentary fades zones. The diagenesis of the target strata is weak, and sedimentary conditions are the main factor affecting reservoir quality. The research results provide reference for the exploration and development of deep-water turbidite sandstone oil and gas reservoirs in West Africa. [ABSTRACT FROM AUTHOR]

Lysine plays a crucial role in promoting development, enhancing immune function, and improving the function of central nervous system tissues. The two configurational isomers of amino acids have significantly different effects. Currently, methods for chiral recognition of lysine have been reported; however, previous detection methods have drawbacks such as expensive equipment and complicated detection processes. Fluorescence analysis, on the other hand, boasts high sensitivity, strong selectivity, and simple operation. In this study, we synthesized four novel Binaphthyl-Amine (BINAM)-based fluorescent probes capable of specifically identifying the L-configuration of lysine among the twenty amino acids that constitute human proteins. The enantiomeric fluorescence enhancement ratio (ef or ΔIL/ΔID) reached up to 15.29, demonstrating high enantioselectivity. In addition, we assessed the probe's recognition capabilities under varying pH levels, reaction times, and metal ion conditions, along with its limit of detection (LOD) and quantum yield. Our results suggest that this probe serves as a highly stable tool for the detection of chiral lysine. [ABSTRACT FROM AUTHOR]