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Photo-mixing with its advantages of ultra-large bandwidth and precise tunability has emerged as an important technique for terahertz (THz) wave generation. Recently, graphene photodetectors exhibiting a large bandwidth are expected to further boost the development of integrated THz emitters. Here, we fabricate a sub-THz emitter based on a large-bandwidth silicon–plasmonic graphene (SPG) photodetector integrated with a broadband rounded bow-tie THz antenna. The SPG sub-THz emitter is experimentally demonstrated to emit sub-THz waves with a radiation spectrum from 50 to 300 GHz. A maximum sub-THz emission power of 5.4 nW is obtained at 145 GHz with only 3 mW input light power. The SPG sub-THz emitter can be fabricated by a CMOS-compatible process, which offers enormous opportunities for its use in a variety of THz applications.

ObjectiveOur study was designed to investigate whether the indoleamine-2,3-dioxygenase (IDO)-mediated kynurenine/tryptophan (KYN/TRP) pathway participates in the development of emotional deficits from ethanol addiction/withdrawal mice.MethodsThe expression of proinflammatory factors, including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), was tested by enzyme-linked immunosorbent assay (ELISA). The IDO levels in the hippocampus, cerebral cortex, and amygdala were measured by polymerase chain reaction (PCR) and western blot, and the neurotransmitters were tested by high performance liquid chromatography (HPLC). Emotional deficits of mice were evaluated by behavioral tests.ResultsExpression levels of inflammatory factors (TNF-α, IL-1β, and IL-6) were increased in mice after 4 weeks of alcohol exposure. As for indoleamine 2,3-dioxygenase (IDO) expression, only the subtype IDO1 was found to increase at both mRNA level and protein level in all the tested brain regions of ethanol addiction/withdrawal mice. In behavioral tests, mice exposed to alcohol showed gradually declined memory function accompanied by anxiety-like and depressive-like behaviors. Meanwhile, increased expression of KYN, decreased expression of 5-HT, and abnormal expression of 3-HK and KA were found in the hippocampus, cerebral cortex, and amygdala of ethanol addiction/withdrawal mice. Interestingly, the IDO1 inhibitor, 1-methyl-L-tryptophan (1-MT), reversed all above alterations induced by ethanol in mice.ConclusionOur results suggested that the TRP/KYN pathway, medicated by IDO1, in the hippocampus, cerebral cortex, and amygdala, plays an important role in the development of emotional deficits caused by ethanol addiction and withdrawal.

In conventional thin materials, the diffraction limit of light constrains the number of waveguide modes that can exist at a given frequency. However, layered van der Waals (vdW) materials, such as hexagonal boron nitride (hBN), can surpass this limitation due to their dielectric anisotropy, exhibiting positive permittivity along one optic axis and negativity along the other. This enables the propagation of hyperbolic rays within the material bulk and an unlimited number of subdiffractional modes characterized by hyperbolic dispersion. By employing time-domain near-field interferometry to analyze ultrafast hyperbolic ray pulses in thin hBN, we showed that their zigzag reflection trajectories bound within the hBN layer create an illusion of backward-moving and leaping behavior of pulse fringes. These rays result from the coherent beating of hyperbolic waveguide modes but could be mistakenly interpreted as negative group velocities and backward energy flow. Moreover, the zigzag reflections produce nanoscale (60 nm) and ultrafast (40 fs) spatiotemporal optical vortices along the trajectory, presenting opportunities to chiral spatiotemporal control of light-matter interactions. Supported by experimental evidence, our simulations highlight the potential of hyperbolic ray reflections for molecular vibrational absorption nanospectroscopy. The results pave the way for miniaturized, on-chip optical spectrometers, and ultrafast optical manipulation. [ABSTRACT FROM AUTHOR]

Objective The Tongshanling deposit in the western Nanling metallogenic belt of Hunan Province is a skarn Cu polymetallic deposit related to Ⅰ-type granodiorite. Recently, a thick stratiform W-Mo skarn ore body has been found in the limestone of the Qiziqiao Formation far from the granodiorite intrusion. Its geological characteristics, mineral assemblages and genetic types are different from those of the ore bodies in the contact zone of the intrusion. Methods In this study, timing and genesis of the Tongshanling stratiform are analysed, through field investigation, microscopic identification, in situ U-Pb dating of garnet, and LA-ICP-MS trace element analysis of scheelite. Results The following four stages of mineralization are identified: garnet skarn, epidote and chlorite skarn, quartz sulfide and quartz calcite. The U-Pb concordant age of garnet is (160.4±4.2) Ma (MSWD=0.79), is significantly later than that of the granodiorite (~167 Ma) and similar to that of the granite porphyry (~161 Ma). The total rare earth element (ΣREE) distribution pattern of the garnet core is light rare earth element (LREE) enrichment and heavy rare earth element (HREE) flat and is similar to the whole-rock ΣREE model of granite porphyry. The ΣREE distribution pattern of garnet rims is LREE-depleted and is different from that of garnet in contact zone skarns. Scheelite associated with epidote can be divided into three stages. ΣREE modes of the three stages are all LREE enrichment and HREE depletion, but the ΣREE content decreases significantly from the first stage (Sch1-a, 332×10-6-353×10-6) to the second stage (Sch1-b, 144×10-6-301×10-6) and the third stage (Sch1-c, 4.05×10-6-31.8×10-6). Scheelite associated with chlorite (Sch2) shows LREE enrichment and HREE depletion, and their ΣREE content is 51.2×10-6-139×10-6. W-Mo mineralization is mainly concentrated in the retrograde stage. The Sch1-b and Sch2 stages have higher oxygen fugacities are the main stage of W mineralization, while the other stages (Sch1-a and Sch1-c) with lower oxygen fugacities are the main stage of Mo mineralization. Comprehensive analysis reveals that the stratiform skarn and contact zone skarn in the Tongshanling and Weijia deposits are different metallogenic systems. The stratiform skarn may be related to the granite porphyry with a relatively high degree of fractionation. Conclusion More attention should be given to the late granite porphyry in deep within and at the edge of the Tongshanling deposit.

Addressing the issues of low harvesting efficiency and high losses in current pod pepper harvesters, this study presents the design of a bionic comb finger pod pepper picking device and an inclined double-spiral bell pepper harvester to improve the harvest rate and reduce loss rate. Through the utilization of discrete element simulation software EDEM, a discrete element model for pod peppers is established. Additionally, a simulation platform for ground drop loss during pod pepper picking is developed, enabling exploration of the movement trajectory and velocity changes of the pod pepper elements. The study also conducts an analysis on the impact of the speed of the picking rollers X1, the feeding speed of pod peppers X2, and the spacing between the two picking rollers X3 on ground drop losses. Based on the results of the single-factor test, the Box–Behnken response surface test was used to optimize the working parameters of the picking device, which resulted in the optimal combination of the working parameters of the picking device: the speed of the picking rollers was 680.41 rpm, the feeding speed of the pod peppers was 0.5 m/s, and the spacing between the two picking rollers was 12 mm, which resulted in the loss rate of pod peppers on the floor of the ground being 3.526%.

Due to the increasing concern with the environmental safety and recyclability, natural fiber-reinforced composites have attracted more and more attention. In the present work, braking composite samples with and without wet granulation were fabricated and their physical, mechanical, and environmental properties were investigated systematically. The experimental results showed that the use of the wet granulation technology did not improve significantly the water absorption and impact strength properties of the braking composite samples but considerably improved their density and environmental performance in comparison to the braking composite sample without wet granulation, especially the environmental performance. Among the braking composite samples with wet granulation, with the decreasing of the resin contents, the density was decreased gradually, the water absorption was decreased and then increased, and the impact strength was increased. Samples FG-13 and FG-11 had a relatively low dust capacity, and sample FG-5 was the highest. The method of the braking composite preparation in the present work may serve as a useful guide to produce a strong low-resin environmental-friendly composite for automotive components.

This study utilized the mallard’s foot as the subject, examining the bone distribution via computed tomography (CT) and analyzing pertinent parameters of the tarsometatarsal bones. Additionally, gross anatomy methods were employed to elucidate the characteristics of the toes and webbing bio-structures and their material composition. Biologically, the mallard’s foot comprises tarsometatarsal bones and 10 phalanges, enveloped by fascia, tendons, and skin. Vernier calipers were used to measure the bones, followed by statistical analysis to acquire structural data. Tendons, originating in proximal muscles and terminating in distal bones beneath the fascia, facilitate force transmission and systematic movement of each segment’s bones. Regarding material composition, the skin layer serves both encapsulation and wrapping functions. Fat pads, located on the metatarsal side of metatarsophalangeal joints and each phalanx, function as cushioning shock absorbers. The correlation between the force applied to the tarsometatarsal bones and the webbing opening angle was explored using a texture analyzer. A simplified model describing the driving force behind the webbing opening angle was introduced. Furthermore, we designed a bionic foot, contributing a foundational reference for anti-sinking bionic foot development.

Leading agricultural enterprises attracting farmers to participate in vertical collaboration within the industry chain can expedite the process of agricultural industrialization and help achieve rural revitalization. This study focuses on table grape growers in the Yangtze River Delta region of China as the research subjects. Instead of examining the impact of specific elements individually on farmers’ involvement in vertical collaboration within the industry chain, this study emphasizes the combination of multiple factors influencing farmers’ engagement. Employing a fuzzy-set qualitative comparative analysis and adopting a configurational perspective, this research investigates how six factors—growers’ age, ratio of sales income to household income, production scale, market distance, financial support, and technical support—combine to influence farmers’ participation in vertical collaboration within the industry chain. This study reveals that leading enterprises can indeed promote farmers’ participation in vertical cooperation within the agricultural chain, and four pathways are identified. Based on these findings, three configurations are summarized: risk-averse, resource-constrained, and burden-alleviating. Specific strategies and recommendations for targeting each of these configurations are proposed based on the findings, along with policy suggestions for regulating the six factors, both by the enterprises themselves and by the government.

Abstract To solve the inspection problems in cotton storage, as well as the need for environmental monitoring in the process of modern cotton bale storage, an intelligent inspection and temperature and humidity intelligent monitoring system based on RFID cotton bale was developed by adopting RFID (Radio Frequency Identification) technology, wireless temperature and humidity real-time monitoring technology and handheld terminal intelligent inspection technology. The system was composed of RFID positioning inspection module and temperature and humidity real-time monitoring and transmission module. The artificial neural network (ANN) based on the particle swarm optimization (PSO) algorithm was used to process the monitoring data of the system by Gaussian filtering, and an accurate classification model of RSSI and label position was established. The test results showed that: Through the comparative analysis of the RFID indoor positioning algorithm, the positioning error of the PSO-ANN algorithm was small. In the actual cotton bale warehouse test, the relative error of positioning and monitoring for RFID cotton bale intelligent inspection and monitoring system was less than 6.7%, which effectively improved the working efficiency of inspection personnel and the security of cotton bale storage. The relative error of temperature and humidity was less than 8% and less than 7%, which could display the temperature and humidity information in real time and meet the real-time demand. This study improved the management personnel's effective positioning and inspection of the cotton bale, prevented the loss of cotton bale, reduced the deterioration probability of cotton bale, and effectively improved the storage management level of the cotton bale. It was of great practical significance to realize the networking, automation, and intelligence of cotton bale storage management.

Due to the advantages of hole forming and transplanting at the same time, even on a film-covered field ridge, the cup-hanging transplanter has become one of the most widely used transplanters in agricultural operations. The cup-hanging planter is the main operating part of the transplanter. Different shapes of the hanging cup can affect the soil action mechanism, cavitation performance, and planting quality. In this study, the discrete element simulation software EDEM and the multi-body system dynamics analysis software RecurDyn are used to carry out the coupling simulation analysis. The results showed that the planting holes formed by hanging cups with two different shapes and under four different planting frequencies all met the planting requirements. After soil reflow, the transverse dimensions of the two holes are similar, and the longitudinal dimensions of the hole of the conical hanging cup are smaller than those of the multilateral hanging cup. Under the same planting frequency, the tear film size and hole-forming performance of the conical cup were better than those of the multilateral hanging cup. The result of the simulation test is consistent with that of the bench test, which proved the feasibility of using EDEM-RecurDyn coupling simulation to predict the hole-forming characteristics of the cup-hanging planter. The filmless hole-forming performances of two different shapes of hanging cups are close to each other. In terms of the film damage of film hole-forming, the conical cup is better than that of the multilateral hanging cup.

Due to the cold and dry climate during the winter season of Central Asia, in order to prevent frostbite and vines drying out for wine grapes, the common methods are burying the vines in winter under a thick layer of soil and then cleaning them out in the next spring. The design of existing vine digging machinery is not precise enough and can only remove the outer layer of the soil on both sides and the top. It cannot clean the soil from the central area of the buried vine. Sometimes, the branches and buds get damaged due to uneven driving condition. To solve the problem, an innovative non-contact blower was designed and tested to clean the vine. In this paper, the design specifications and operation parameters of the blower were determined according to the agronomic properties of the grapevines. Fluent-EDEM coupling, that is, with the help of Engineering discrete element method (EDEM) and CFD fluid simulation software Fluent, was the most common method for dynamic simulation of gas-solid two-phase flow. The Fluent-EDEM coupling simulation was used to simulate the dynamics of soil particles under the action of different wind speeds and blowing patterns, with the goal of a high soil cleaning rate. A prototype of the soil cleaning blower was manufactured and tested at the vineyards of Ningxia Yuquanying Farm in China. The results showed that the blower had an operation efficiency of 4669 m2·h−1, with an average soil removal rate of 80%. The efficiency of covering soil cleaning and rattan raising was greatly improved, and the damage rate of the vines, branches and the buds was greatly reduced.

In order to enhance the fluid mixing in the stirred tank and reduce the power consumption under the condition of full baffle, a sinusoidal sawtooth baffle was established in the present study. Based on the Eulerian–Eulerian method, a numerical simulation of the mixed flow in the stirred tank was conducted, and the reliability of the simulation method was verified by means of PIV experiments. The different structural characteristics of a standard baffle and the sine baffle were compared, to explore the effect of the modified baffle on flow mixing and power consumption in the tank. The outcomes indicate that the sinusoidal sawtooth structure had the effect of reducing drag and shunting, which could lessen the backflow on the backside of the baffle, strengthen the intensity of fluid turbulence and strain rate, improve the uniformity of particle distribution, and significantly lower the power consumption. When the relative tooth height was 0.333 and the relative tooth width was 0.028, the power consumption was reduced by 11.7%.

Improvement of stirring performance is one of the primary objectives in solid–liquid mixing processes, such as the preparation of phase change materials (PCMs) for energy saving in refrigeration and heat pump systems. In this paper, three novel impellers are proposed: pitched-blade punched turbine (PBPT), bionic cut blade turbine (BCBT) and bionic cut punched blade turbine (BCPBT). An experimental test was conducted to validate the stirring system model based on the Eulerian–Eulerian method with the kinetic theory of granular flow. Then the performance of the novel impellers was predicted, studied, and compared. The outcomes indicate that a novel impeller, specifically BCPBT, can effectively suspend particles and dramatically reduce power consumption. A better solid–liquid suspension quality was obtained with an aperture diameter of 8 mm and aperture ratio of 13%. Within the range of impeller speeds and liquid viscosity studied in this this paper, higher impeller speeds and more viscous liquids are more conducive to particle dispersion. One of the most important contributions of this work lies in the design of novel impellers, an extent of energy conservation to 17% and efficient mixing was achieved. These results have reference significance for improving the energy efficiency of temperature regulation systems.

Abstract With the development of large-scale livestock farming, manure pollution has drawn much attention. Conversion by insects is a rapid and cost-effective new method for manure management. Swine manure conversion with maggots (Musca domestica larvae) has developed, and the harvested maggots are often used as animal feed. However, the flow of heavy metals from manure to downstream processes cannot be ignored, and therefore, heavy metal content was measured in untreated raw manure, maggot-treated manure, harvested maggots and maggot-eating chickens (chest muscle and liver) to evaluate potential heavy metal risks. The levels of zinc, copper, chromium, selenium, cadmium and lead had significant differences between untreated raw manure and maggot-treated manure. The concentrations of all detected heavy metals, except for cadmium and selenium, in maggots met the limits established by the feed or feed additive standards of many countries. The bioaccumulation factor (BAF) of heavy metals decreased with the increase of the maggot instar, indicating that heavy metals were discharged from the bodies of maggots with the growth of maggots. Also, the contents of overall heavy metals in chickens fed harvested maggots met the standards for food. In conclusion, regarding heavy metals, it is eco-safe to use maggots in manure management.