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Applying different types of fertilizers to different depths of soil according to demand is advantageous in that it can optimize the distribution of nutrients in arable soil, adjust the nutrient supply of each growth stage of wheat, and increase grain yield. In the study, a layered fertilization opener that could realize the layered fertilization was developed. The interaction model between the opener, fertilizer and soil was established using EDEM simulation software. A response surface analysis was used to determine the optimal parameters of the opener. Specifically, the horizontal distance between the fertilizer drop openings was 140 mm, the machine speed was 1.05 m/s, and the angle of the opener was 37°. Furthermore, field experiments demonstrated that the average depth of upper layer was 8.39 cm, the average depth of middle layer was 16.465 cm, the average depth of lower layer was 24.025 cm, the average spacing of upper layer was 8.075 cm, and the average spacing of lower layer was 7.6 cm. The corresponding findings demonstrated that the layering effect of the opener met the requirements of the fertilization standard. [ABSTRACT FROM AUTHOR]

Since remote sensing images are captured from the top of the target, such as from a satellite or plane platform, ship targets can be presented at any orientation. When detecting ship targets using horizontal bounding boxes, there will be background clutter in the box. This clutter makes it harder to detect the ship and find its precise location, especially when the targets are in close proximity or staying close to the shore. To solve these problems, this paper proposes a deep learning algorithm using a multiscale rotated bounding box to detect the ship target in a complex background and obtain the location and orientation information of the ship. When labeling the oriented targets, we use the five-parameter method to ensure that the box shape is maintained rectangular. The algorithm uses a pretrained deep network to extract features and produces two divided flow paths to output the result. One flow path predicts the target class, while the other predicts the location and angle information. In the training stage, we match the prior multiscale rotated bounding boxes to the ground-truth bounding boxes to obtain the positive sample information and use it to train the deep learning model. When matching the rotated bounding boxes, we narrow down the selection scope to reduce the amount of calculation. In the testing stage, we use the trained model to predict and obtain the final result after comparing with the score threshold and nonmaximum suppression post-processing. Experiments conducted on a remote sensing dataset show that the algorithm is robust in detecting ship targets under complex conditions, such as wave clutter background, target in close proximity, ship close to the shore, and multiscale varieties. Compared to other algorithms, our algorithm not only exhibits better performance in ship detection but also obtains the precise location and orientation information of the ship. [ABSTRACT FROM AUTHOR]

Background: Duck circovirus may predispose the host to immunosuppression and may serve as an immunological trigger for further complicated disease progression. Due to the lack of a cell culture system for propagating DuCV, little is known regarding the molecular biology and pathogenesis of DuCV. The aim of this study was to describe the construction and initial in vivo characterization of full-length DNA clones of DuCV (pIC-Mu2DuCV) and its infectivity under in vivo conditions. Method: The constructed pIC-Mu2DuCV contained two copies of the whole DuCV genome and an introduced Xho I restriction enzyme site. Eighty-one 10-day-old conventional ducklings that were free of DuCV were randomly divided equally into three groups (1, 2 and 3). The ducklings in groups 1, 2 and 3 were inoculated intramuscularly with pIC-Mu2DuCV, wild-type virus GH01 and PBS, respectively. Subsequently, all of the ducklings were examined clinically, which were each given a physical condition score, and their rectal temperatures were taken daily during the experimental period. DuCV genomes in serum samples and in various tissues from all of the ducklings at 0, 1, 3, 5, 7, 10, 15, 21 and 28 DPC were detected by PCR and real-time quantitative PCR, respectively. Results: The average daily weight gain (ADWG) of group 3 was significantly higher than those of groups 1 and 2, and the temperature of all ducklings was stable between 41.7 °C and 42.2 °C. The clinical values (physical condition scores) of groups 1, 2 and 3 were 12.5, 15.6 and 0, respectively. In addition, viremia occurred at 15 and 10 days post-challenge (DPC) in groups 1 and 2, and antibodies could be detected in these ducklings at 21 and 15 DPC. Proliferation ability analysis showed that the viral titers of group 1 were lower than those of their parental viruses in group 2. Conclusion: This study shows that the rescued viruses are not significantly different but exhibit lower pathogenicity and proliferation ability compared with the parental virus. The results will facilitate future studies on DuCV pathogenesis and biology. [ABSTRACT FROM AUTHOR]

Traditional maize ear harvesters mainly rely on manual identification of fallen maize ears, which cannot realize real-time detection of ear falling. The improved You Only Look Once-V4 (YOLO-V4) algorithm was combined with the channel pruning algorithm to detect the dropped ears of maize harvesters. K-means clustering algorithm was used to obtain a prior box matching the size of the dropped ears, which improves the Intersection Over Union (IOU). Compare the effect of different activation functions on the accuracy of the YOLO-V4 model, and use the Mish activation function as the activation function of this model. Improve the calculation of the regression positioning loss function, and use the CEIOU loss function to balance the accuracy of each category. Use improved Adam optimization function and multi-stage learning optimization technology to improve the accuracy of the YOLO-V4 model. The channel pruning algorithm was used to compress the model and distillation technology was used in the fine-tuning of the model. The final model size was only 10.77% before compression, and the test set mean Average Precision (mAP) was 93.14%. The detection speed was 112 fps, which can meet the need for real-time detection of maize harvester ears in the field. This study can provide a technical reference for the detection of the ear loss rate of intelligent maize harvesters. [ABSTRACT FROM AUTHOR]

As a promising charge carrier transfer scheme, optical coupling could potentially improve the performance of an optoelectronic device for energy harvesting based on well developed nanotechnology. By extracting carriers optically, the functional features of the nano-structured material could be better used by minimizing the concerns about its electrical properties. In this paper, we present a rigorous electromagnetic model to analyze the optical carrier transfer problem. The flow of the energy is analyzed carefully by the photon transfer spectrum, and the photon emitters (electron-hole pairs) are assumed in a thermal equilibrium described by Bose-Einstein distribution. The result shows that an energy selective carrier transfer can be optically achieved at the device level by integrating the emitter and receiver into a nano-optical resonator, where both the photon emission and absorption are significantly amplified by a near-field coupling around the resonant frequency. General design and optimization schemes in practice are addressed by examining the influence of the photonic design and an energy dependent emissivity of the emitter, which can be used to develop the optical contacting concept further. [ABSTRACT FROM AUTHOR]

The article focuses on achieving ideal transistor characteristics in conjugated polymer semiconductors. The topics discussed include the challenges of achieving ideal transistor behavior in polymer OTFTs, the identification of polymer candidates with low energetic disorder and spatially uniform energetic landscapes, and the demonstration of near-ideal transistor behavior in the semicrystalline polymer PffBT4T-2DT.

A series of compression experiments was conducted to observe the pore-water pressure variations of saturated warm frozen soils over time. The results indicate that saturated warm frozen soils can exhibit excess pore-water pressure when subjected to external loads. The pore-water pressure fluctuates rather than varying monotonically, and it gradually increases with increasing compressive deformation as the pores are compressed. Furthermore, the permeability of the soil allows pressure dissipation. Thus, the porewater pressure is continuously changing because of the interactions between these two opposing processes. The peak pore-water pressure follows an exponential relationship with the soil temperature and decreases to a steady value as the temperature decreases. A dissipation trend is observed after the peak pressure is reached. This trend reflects the influence of consolidation in the deformation of warm frozen soils. As the temperature increases, the role of the consolidation becomes more significant. [ABSTRACT FROM AUTHOR]

Garlic planting requires a single seed with a scaly bud upward and vertically. In this study, an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel, a correcting mechanism, and an automatic control system. Three factors influenced device performance: characteristics of garlic seeds, limited notch diameter of the seed placed funnel, and funnel taper of the seed placed funnel. The most optimal structural parameters of the seed placed funnel were determined via theoretical analysis. The research samples of Lanling and Jinxiang garlic were divided into three groups according to their respective sizes. 3D design software (Solidworks) was used to simulate the above three factors and analyze their rules of action. The obtained simulation results demonstrated that the suitable range of funnel taper and limited notch diameter of seed placed funnel for the three groups of seed were from 40° to 60° and 6-8 mm, respectively. The bench test showed that when the funnel taper was 60° and the limited notch diameter was 10 mm, the success rates of the three groups’ seeds in terms of scaly bud directing were 89.8%, 91.6% and 96.6% respectively, which satisfied the agricultural requirements of garlic planting. Accordingly, the corresponding results may promote the study and improvement of garlic intelligent planting equipment. [ABSTRACT FROM AUTHOR]

Cs2SnI6 is a variant on tin-iodide solution-processable materials and may lead to a lead-free material for use in next-generation photovoltaic cells and other optoelectronics. So far, only a few studies have been conducted where shape and geometry control of Cs2SnI6 nanocrystals is demonstrated. Here we report a general approach to directly synthesize Cs2SnI6 of two-dimensional (2D) layered nanoplatelets as well as three-dimensional (3D) nanocrystals. The shape of Cs2SnI6 nanocrystals could be engineered into 3D nanoparticles and different 2D nanoplatelets with well-defined morphology by choosing different organic acid and amine ligands via a hot injection process. Moreover, the thickness of layered 2D nanoplatelets could be adjusted by changing the amount of Cs-oleate present during the synthesis. The photoluminescence emission peaks changed from 643 to 742 nm based on nanomaterial shape. Our method provides a facile and versatile route to rationally control the shape of the Cs2SnI6 nanocrystals, which will create opportunities for applications in lead-free optoelectronics. [ABSTRACT FROM AUTHOR]

Objective: To research the clinical effect of nourishing liver and kidney along with supplementing Chong-Ren channels (NSGSCR) with acupuncture in the treatment of patients who were undergoing in vitro fertilization-embryo transfer (IVF-ET). Methods: Twenty eight women undergoing IVF-ET were randomly divided into two groups, 16 in the treatment group and 12 in the control group. Both were treated with conventional Western medical treatment, but the treatment group also received NSGSCR treatment along with the Western Medication for 14 days as one course of treatment. Results: After treatment, scores of fertilization 7/16 and pregnant 6/16 in the treatment group were all better than those in the control group, (3/12 and 2/12) respectively (P < 0.05). Conclusion: NSGSCR with conventional Western medicine treatment is better than Western medical treatment alone in increasing fertilization rate and pregnancy rate in patients after IVF-ET. [ABSTRACT FROM AUTHOR]

The unique tunable bandgaps and straightforward synthesis of colloidal quantum dots make them promising low-cost materials for photovoltaics. High-performance colloidal quantum dot solar cells rely on good-quality electron transporting layers (ETLs) to make carrier selective contacts. Despite extensive use of n-type oxides as ETLs, a detailed understanding of their surface and interface states as well as mechanisms to improve their optical properties are still under development. Here, we report a simple procedure to produce MgCl2 passivated ZnO nanoparticles ETLs that show improved device performance. The MgCl2 treated ZnO electron transporting layers boost the PbS colloidal quantum dot cell efficiency from 6.3% to 8.2%. The cell exhibits reduced defects leading to significant improvements of both FF and Jsc. This low-temperature MgCl2 treated ZnO electron transporting layer may be applied in solution processed tandem cells as a promising strategy to further increase cell efficiencies. [ABSTRACT FROM AUTHOR]