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During the field operation of rice combine harvester, the vibration generated by vibration component will only reduce mechanical reliability and yield, but also cause resonance in the human body, leading to a decrease in driving comfort and even damage to the driver's health. To study the impact of combine harvester vibration on driving comfort, a certain type of tracked rice combine harvester was selected as the research object, and vibration tests were carried out based on vibration source analysis in the driving cab during field harvesting operations. The study showed that under the influence of field road conditions and crop flow, the operating speed of the engine, threshing rotor, stirrer, cutting blade, threshing cylinder, vibration sieve and conveyor were fluctuating, and their rotation and reciprocating motion would produce vibration excitation in the driving cab. A spectrum analysis was conducted on the acceleration signal of the driver's cab, and it was found that vibration frequencies at three measuring points, namely the pedal, control lever, and seat, can reach up to 36.7~43.3 Hz. These frequencies can cause resonance in various parts of the driver's body, such as the head and lower limbs, leading to symptoms such as dizziness, throat discomfort, leg pain, defecation anxiety, and frequent urination, and even affect vision of the driver. At the same time, a weighted root-mean-square acceleration evaluation method was used to evaluate the driving comfort of the harvester. The evaluation method showed that the vibration at the foot pedal (Aw1 = 4.4 m/s2>2.5 m/s2) caused extreme discomfort, while the vibration at the seat (0.5 m/s2< Aw2 = 0.67 m/s2<1.0 m/s2) and the control lever (0.5 m/s2< Aw3 = 0.55 m/s2<1.0 m/s2) caused relatively less discomfort. This research can provide some reference for the optimization design of the joint harvester driver's cab. [ABSTRACT FROM AUTHOR]

Electrode materials play a crucial role in the efficient treatment of organic wastewater through electrocatalytic oxidation. Semi-coke after activation has recently been found as a potential and reliable electrode material, and TiO2-coated electrodes have been developed for a range of applications owing to their superior electro-catalytic performance. Therefore, this study focused on Rhodamine B (RhB) removal via electro-catalysis using a TiO2/activated semi-coke (TiO2/ASC) composite, and the synthesized composite was characterized by SEM, XRD, FT-IR, and UV-DRS analysis. The results showed that TiO2 particles were evenly distributed on the ASC surface, and TiO2 could reduce the value of the band gap and facilitate electron transport in electrocatalysis. The influencing factors during RhB removal with the TiO2/ASC composite were also investigated, with an initial pH value of 2, a bias voltage of 16 V, an initial concentration of 3 mg/L, and a 50 mg dosage of the TiO2/ASC composite, indicating that RhB could be completely removed after 45 min. A second-order quadratic model was established to describe the relationship between the RhB removal rate and three significant factors: dosage, reaction time, and initial pH. Response surface methodology was used to describe the interactive effects of three variables, which was effective for understanding the behavior of electro-catalysis on the TiO2/ASC composite. The kinetics study demonstrated that RhB removal during the electro-catalysis process confirmed pseudo-first-order kinetics. Highlights: It provides a new pathway for the utilization of affordable semi-coke. TiO2 loaded on activated semi-coke reduce band gap and promote electron transport. It establishes the relationship between the RhB removal rate and three main factors. It describes the interactive effects of three variables in electro-catalysis process. RhB removal during the electro-catalysis confirms pseudo-first-order kinetics. [ABSTRACT FROM AUTHOR]

High thermal conductive polymeric composites are extremely desired for the thermal management of electronic devices due to the rapid development of the modern microelectronic industry. Herein, the functionalized boron nitride (BN) and magnesium oxide (MgO) hybrid fillers (f‐BN@f‐MgO) were synthesized and used to prepare the enhanced thermal conductive epoxy (EP) composites through the hot‐pressing method. The results demonstrated that the covalent binding of BN and MgO in the hybrid fillers reduced the interface thermal resistance effectively between fillers and matrix and the hot‐pressing induced force facilitated the construction of the continuous thermal conduction paths. Consequently, the as‐prepared epoxy composite at 40 wt% hybrid fillers loading had high thermal conductivity (TC) (1.97 W/[m·K]), outstanding insulating performance (6.9 × 1015 Ω cm) and excellent thermal stability. Furthermore, a probable thermal conduction mechanism was proposed to illustrate the high TC of the epoxy composite. Therefore, this study provides a new approach to preparing epoxy composites with outstanding performances. [ABSTRACT FROM AUTHOR]

After the box girder was poured, the cement hydration generated heat and produced a large temperature difference in the girder, which may lead to the cracking. In order to study the hydration heat distribution and cracking risk of three-cell girder after pouring, the scale model of box girder was poured, 258 temperature sensors, solar radiation sensors and wind speed sensor were embedded in the model. Data receiving frequency was once every 30 min, and wireless acquisition module for data collection was used. After 96 h' observation of temperature, the temperature field distribution of hydration heat of three-cell concrete girder was obtained. The finite element model of temperature field considering solar radiation and atmospheric convection was established. The maximum temperature change due to solar radiation was 29.8% of temperature change of hydration heat. The space and time model of vertical temperature difference during heat of hydration of concrete three-cell box girder was proposed for the first time. Based on response surface model and finite element model, the maximum vertical temperature difference of different web was proposed and was verified at the Wangjiahe Bridge. The predicted values of the Wangjiahe Bridge were in approximately agreement with the measured values. Compared to the initial concrete temperature of 35 °C without geotextile cover, the initial concrete temperature of 15 °C with 8 mm geotextile reduced the vertical temperature difference to 24.7% at most. [ABSTRACT FROM AUTHOR]

The fossil record of jaguar lineage (or jaguar-like animal), i.e., Panthera gombaszogensis and Panthera onca, is one of the best and complete among the mammals, making it one of the best-known living species with knowledge of origin, dispersal, and morphological evolution. However, a large gap is present in eastern Asia, which is the gateway for jaguar migration from the Old World to the New World. Here we report a nearly complete mandible from the Middle Pleistocene deposits of Jinyuan Cave, Luotuo Hill of Jinpu New District, Dalian, Liaoning Province of northeastern China. The mandibular morphology fits that of the jaguar, and the dental traits are closest to P. gombaszogensis and Irvingtonian P. onca, but shows robust premolars and represents a new subspecies P. g. jinpuensis. The new find fills the geographic gap for jaguar linage, and supports a northern dispersal routine from western Asia-central Asia-northeastern China to North America, whereas the southern China Early Pleistocene seems to be occupied by a similar sized but taxonomically different pantherine cat. [ABSTRACT FROM AUTHOR]

Purpose: The TMEM196 protein, which comprises four membrane-spanning domains, belongs to the TMEM protein family. TMEM196 was identified as a candidate tumor suppressor gene in lung cancer. However, its role and mechanism in lung cancer metastasis remain unclear. Here, we study the role of TMEM196 in tumor metastasis to further verify the function in lung cancer. Methods: In this study, we used qRT-PCR, western blot analysis and immunohistochemistry to examine the expression levels of TMEM196 and related proteins in lung cancer tissues and tumor cells. We utilized Transwell assays, xenograft nude mouse models, and TMEM196−/− mouse models to evaluate the effects of TMEM196 on tumor invasion and metastasis. Finally, we used bioinformatics analysis and dual-luciferase reporter gene assays to explore the molecular mechanism of TMEM196 as a tumor suppressor. Results: We found that TMEM196 mRNA and protein expression levels were significantly decreased in lung cancer tissues and cells. Low expression of TMEM196 in clinical patients was associated with poor prognosis. TMEM196 strongly inhibited tumor metastasis and progression in vitro and in vivo. The primary lung tumors induced by tail vein-inoculated B16 cells in TMEM196−/− mice were significantly larger than those in TMEM196+/+ mice. Mechanistically, TMEM196 inhibited the Wnt signaling pathway and repressed β-catenin promoter transcription. TMEM196 silencing in lung cancer cells and mice resulted in significant upregulation of the expression of β-catenin and Wnt signaling pathway downstream target genes (MMP2 and MMP7). Decreasing β-catenin expression in TMEM196-silenced cancer cells attenuated the antimetastatic effect of TMEM196. Conclusions: Our results revealed that TMEM196 acts as a novel lung cancer metastasis suppressor via the Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Quantum metrology, including quantum sensing and imaging, offers significant advantages over classical methods in terms of sensitivity and accuracy. This paper presents its potential applications and challenges in civil engineering. We discuss recent advances and highlight how quantum technologies can improve engineering monitoring practices. Despite the infancy of quantum sensing and imaging in outdoor civil engineering applications, their high precision makes them promising for overcoming traditional limitations. We further suggest future directions for integrating quantum metrology into civil engineering projects to improve safety and efficiency. • Quantum metrology, including sensing and imaging, presents promising utility in civil engineering with high-precision detection capabilities. • Quantum sensing technology has the potential to go beyond classical detection limits, offering significant advantages for monitoring. • Quantum imaging technology enables remote and extreme condition monitoring, improving our ability to assess structural integrity. • Although this technology is still in its infancy, more research and funding is needed to fully exploit its benefits in civil engineering. [ABSTRACT FROM AUTHOR]

FeCrAl alloy has excellent mechanical properties and is of great significance in nuclear fuel cladding materials. The effects of microalloying elements Re and Be on the microstructure and mechanical properties of Fe-13Cr-6Al-0.5Nb-2Mo-0.1Y alloy were investigated. The results indicated that Nb is substituted by a small amount of Re in the Laves phase, while Be aggregates near the Laves phase. The addition of Re and Be can improve the hardness and strength of Fe-13Cr-6Al-0.5Nb-2Mo-0.1Y alloy, refine its grain size, and also increase the recrystallization temperature. Due to the addition of Be, the fracture mode of the alloy was changed from ductile fracture to cleavage fracture, while the Re -containing alloy still maintained ductile fracture. The results provide guidance for further development of FeCrAl nuclear fuel cladding materials. [Display omitted] • Nb is substituted by Re in the Laves phase and Be aggregates near the Laves phase. • The addition of Re and Be can improve mechanical properties. • The fracture mode was changed due to the addition of Be. [ABSTRACT FROM AUTHOR]