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Lateritic soils in tropical regions feature cohesive textures and high specific resistance, driving up energy demands for tillage and harvesting machinery. However, current equipment designs lack discrete element models that account for soil moisture variations, and the microscopic effects of water content on lateritic soil deformation remain poorly understood. This study aims to calibrate and validate discrete element method (DEM) models of lateritic soil at varying moisture contents of 20.51%, 22.39%, 24.53%, 26.28%, and 28.04% by integrating the Hertz–Mindlin contact mechanics with bonding and JKR cohesion models. Key parameters in the simulations were calibrated through systematic experimentation. Using Plackett–Burman design, critical factors significantly affecting axial compressive force—including surface energy, normal bond stiffness, and tangential bond stiffness—were identified. Subsequently, Box–Behnken response surface methodology was employed to optimize these parameters by minimizing deviations between simulated and experimental maximum axial compressive forces under each moisture condition. The calibrated models demonstrated high fidelity, with average relative errors of 4.53%, 3.36%, 3.05%, 3.32%, and 7.60% for uniaxial compression simulations across the five moisture levels. Stress–strain analysis under axial loading revealed that at a given surface displacement, both fracture dimensions and stress transfer rates decreased progressively with increasing moisture content. These findings elucidate the moisture-dependent micromechanical behavior of lateritic soil and provide critical data support for DEM-based design optimization of soil-engaging agricultural implements in tropical environments.

There are large fertilization/more times/environment complex during natural rubber tree in the process of the growth cycle and difficult to monitor, aim to the special rubber particles fertilizer easy to deliquescence and cause pipe blockage and then lead to fertilization breaks leakage problem, this paper designed a kind of convenient for visual surveillance of rubber particles ditching fertilizer structure. Optimal designed and analyzed reliability its structure characteristics/working principle/core components and monitoring method. The self-running power suspension test shows that when the moisture content of the fertilizer is ⩽0.16, the scraping structure has no obvious stick with fertilizer go down smoothly, and the strip breaking rate index is ⩽ 0.06, the structure basic function indexes meet the design requirements

Because there are many unfair distribution phenomena in the existing distribution model of supply chain financial benefits, it is necessary to establish a fair and reasonable distribution method of benefits. Firstly, this paper analyzes the risks faced by financing companies, core enterprises, banks and third-party logistics enterprises under the prepayment financing model in supply chain finance, and then quantifies the risks of each member enterprises through BP neural network. Finally, the initial benefit distribution model of prepayment financing model is constructed by combining the maximum entropy method, and the initial benefit distribution model is modified by the risk value faced by each member company, and the rational distribution of the interests of each member enterprise is realized.

In the existing agricultural machinery field, the agricultural machinery is generally cumbersome, the transportation, disassembly and assembly, maintenance procedures are more complicated, and the functions are single, and the versatility is not good. This article combines the industrial design standardization and modularization ideas for the trenching fertilizer application machine. Model construction and assembly practice were carried out. The whole machine was built according to independent functions, and divided into racks, fertilisers, trenching assemblies, suspension systems, transmission systems, etc. Modeling of the rack, modeling of the fertilizer turntable, and plowing the modeling process is elaborated. By assembling the functional components and standard parts, the modular design idea can be reused and exchanged in the design of the trenching fertilizer machine. The relevant modules can form the final product through the arrangement and combination. The final assembly entity can be a variety of products, which can better meet the customer's customization needs; the repetitive use of similarity can make the whole product more convenient in manufacturing and maintenance, and the overall machine coordination and appearance are more beautiful.

In this paper, the quantitative control method and system control process of the natural rubber forest quantitative fertilization system are introduced on the basis of the demand for the quantitative fertilization of natural rubber forest and the application process of the rubber forest fertilizing machine. The selection of PLC, frequency converter type selection and software design process are described in detail.

At present, the trenching and fertilization machine has a serious weed plug problem when trenching and fertilization operation in rubber plantation. So a disc cutter and shallow fertilization machine in rubber plantation named 2KF-15 was designed, the design scheme used the front disc cutter cutting the grass, while using the rear of the disc furrow to trenching, the prototype of a disc anti-plugging trenching and shallow fertilization machine was completed. Afterwards, a series of trenching and fertilization field experiments were carried out, and the results showed that the ditching depth of this machine could achieve from 131 to 176 mm, and the average depth could reach 156 mm, the ditching depth stability coefficient could achieve 90.3%; The fertilizer amount of this machine could achieve from 113.2 to 156.4 kg/hm2, the average fertilizer amount reach 134.2kg/hm2, the fertilizer amount stability coefficient could achieve 89.6%, the fertilizer broken rate was 0%, the fertilizer coverage rate of 98.4%;The situation of fertilizer accumulation occurred less by using this machine, and the fertilization performance was relatively stable. This new designed machine for trenching, fertilization and covering the soil were carried out at the same time. So the number of operations could be effectively reduced. This new designed machine does not only meet the agronomic requirements of rubber plantation fertilization, but also provides a reference for the trenching and fertilization operation in other.

After studying and analyzing the types of cutter roller’s movable blades, various arrangements and layouts of movable blades and structures of such cutter roller of current sugarcane leaf shattering and returning machine in China, a totally new cutter roller design is proposed for 1GYF-200 sugarcane leaf shattering and returning machine: blades are arranged in unequally-spaced double-helix symmetry, the movable blades arranged on both sides of the cutter roller are increased appropriately, and combination of two straight blades and one improved L-blade are adopted as movable blades. Comparing with the original prototype, the improved machine’s pick-up rate has increased by 0.8% and shattering rate has improved by 2.5%. This study provides theoretical basis and reference in designing an effective and reliable machine for shattering sugarcane leaves and incorporating it into soil.

Studies in mice reveal that CREB regulated transcription coactivator 2 (CRTC2) acts as a mediator of mTOR signalling in the liver to regulate SREBP1-controlled lipid homeostasis during feeding and diabetes; overexpression of a CRTC2 mutant defective for mTOR regulation improves the lipogenic program and insulin sensitivity in obese mice. Hepatic control of lipid metabolism SREBP1 is an important transcriptional regulator of lipogenesis. Upon insulin stimulation, it is transported from the endoplasmic reticulum to the Golgi where it is processed, then shuttled to the nucleus to induce genes involved in cholesterol and fatty acid synthesis. From studies in mice, Yiguo Wang and colleagues show that the CREB regulated transcription coactivator 2 (CRTC2) acts as a mediator of mTOR signalling in the liver to regulate SREBP1-controlled lipid homeostasis during feeding and diabetes. CRTC2 can disrupt SREBP1 processing and transport by competing with binding to a subunit of COPII. During feeding, mTOR signalling inhibits the action of CRTC2 on SREBP1 processing. Overexpression of a CRTC2 mutant defective for mTOR regulation improves the lipogenic program and insulin sensitivity in obese mice. Abnormal accumulation of triglycerides in the liver, caused in part by increased de novo lipogenesis, results in non-alcoholic fatty liver disease and insulin resistance 1 , 2 . Sterol regulatory element-binding protein 1 (SREBP1), an important transcriptional regulator of lipogenesis, is synthesized as an inactive precursor that binds to the endoplasmic reticulum (ER). In response to insulin signalling, SREBP1 is transported from the ER to the Golgi in a COPII-dependent manner, processed by proteases in the Golgi, and then shuttled to the nucleus to induce lipogenic gene expression 3 , 4 , 5 ; however, the mechanisms underlying enhanced SREBP1 activity in insulin-resistant obesity and diabetes remain unclear. Here we show in mice that CREB regulated transcription coactivator 2 (CRTC2) 6 functions as a mediator of mTOR 7 signalling to modulate COPII-dependent SREBP1 processing. CRTC2 competes with Sec23A, a subunit of the COPII complex 8 , to interact with Sec31A, another COPII subunit, thus disrupting SREBP1 transport. During feeding, mTOR phosphorylates CRTC2 and attenuates its inhibitory effect on COPII-dependent SREBP1 maturation. As hepatic overexpression of an mTOR-defective CRTC2 mutant in obese mice improved the lipogenic program and insulin sensitivity, these results demonstrate how the transcriptional coactivator CRTC2 regulates mTOR-mediated lipid homeostasis in the fed state and in obesity.

Acquired heterotopic ossification (HO) is a painful and debilitating disease characterized by extraskeletal bone formation after injury. The exact pathogenesis of HO remains unknown. Here we show that TGF-β initiates and promotes HO in mice. We find that calcified cartilage and newly formed bone resorb osteoclasts after onset of HO, which leads to high levels of active TGF-β that recruit mesenchymal stromal/progenitor cells (MSPCs) in the HO microenvironment. Transgenic expression of active TGF-β in tendon induces spontaneous HO, whereas systemic injection of a TGF-β neutralizing antibody attenuates ectopic bone formation in traumatic and BMP-induced mouse HO models, and in a fibrodysplasia ossificans progressive mouse model. Moreover, inducible knockout of the TGF-β type II receptor in MSPCs inhibits HO progression in HO mouse models. Our study points toward elevated levels of active TGF-β as inducers and promoters of ectopic bone formation, and suggest that TGF-β might be a therapeutic target in HO. Heterotopic ossification (HO) is a painful disease of unknown etiology characterized by extraskeletal bone formation after injury. Here the authors show that TGF-β is increased in HO lesions, where it promotes the early stages of HO pathology, and demonstrate that TGF-β inhibition ameliorates HO in mice.

Background Various modalities of vaccines against coronavirus disease 2019 (COVID-19), based on different platforms and immunization procedures, have been successively approved for marketing worldwide. A comprehensive review for clinical trials assessing the safety of COVID-19 vaccines is urgently needed to make an accurate judgment for mass vaccination. Main text A systematic review and meta-analysis was conducted to determine the safety of COVID-19 vaccine candidates in randomized controlled trials (RCTs). Data search was performed in PubMed, Embase, Cochrane library, Scopus, Web of Science, and MedRxiv. Included articles were limited to RCTs on COVID-19 vaccines. A total of 73,633 subjects from 14 articles were included to compare the risks of adverse events following immunization (AEFI) after vaccinating different COVID-19 vaccines. Pooled risk ratios ( RR ) of total AEFI for inactivated vaccine, viral-vectored vaccine, and mRNA vaccine were 1.34 [95% confidence interval ( CI ) 1.11–1.61, P  < 0.001], 1.65 (95% CI 1.31–2.07, P  < 0.001), and 2.01 (95% CI 1.78–2.26, P  < 0.001), respectively. No significant differences on local and systemic AEFI were found between the first dose and second dose. In addition, people aged ≤ 55 years were at significantly higher risk of AEFI than people aged ≥ 56 years, with a pooled RR of 1.25 (95% CI 1.15–1.35, P  < 0.001). Conclusions The safety and tolerance of current COVID-19 vaccine candidates are acceptable for mass vaccination, with inactivated COVID-19 vaccines candidates having the lowest reported AEFI. Long-term surveillance of vaccine safety is required, especially among elderly people with underlying medical conditions. Graphic Abstract