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This letter presents a flat-top beam H-plane substrate integrated waveguide (SIW) horn antenna. The radiation from the SIW H-plane horn antenna aperture can be regarded as magnetic current radiation. To obtain the desired radiation patterns, the phase and amplitude distributions of the magnetic current of the horn aperture can be calculated theoretically. By changing the length and deflection angle of the metal-via arrays, the magnetic current distribution on the aperture can be adjusted, and it is consistent with the theoretical calculation. To verify the proposed method, an SIW horn antenna is designed, fabricated, and measured. The measured results are in good agreement with the simulated ones. The proposed horn antenna obtains a flat-top beam in the angle range of ±40 degrees, and the fluctuation is less than 1 dB.

Background: Although the majority of members belonging to the small GTPase Ras superfamily have been studied in several malignancies, the function of RBJ has remained unclear, particularly in non-small cell lung cancer (NSCLC).Objective: The research aims to determine the function of RBJ in NSCLC.Methods: The levels of RBJ protein in tumor tissue and para-carcinoma normal tissue were ascertained via immunohistochemistry (IHC). The growth, migration, and invasion of NSCLC cells were assessed by 5- ethynyl-2-deoxyuridine (EdU) assay, colony formation, cell counting kit-8 (CCK8), transwell and wound healing assays. Furthermore, a nude mouse xenograft model was established to study the function of RBJ in tumorigenesis in vivo.Results: The IHC analysis revealed that the protein levels of RBJ were notably increased in tumor tissue and positively associated with the clinical stage. In addition, the knockdown of RBJ restrained the growth, invasion, and migration of NSCLC cell lines by inhibiting the epithelial-mesenchymal transition (EMT) through the MEK/ERK signaling pathway. Accordingly, opposite results were observed when RBJ was overexpressed. In addition, the overexpression of RBJ accelerated tumor formation by A549 cells in nude mice.Conclusion: RBJ promoted cancer progression in NSCLC by activating EMT via the MEK/ERK signaling. Thus, RBJ could be used as a potential therapeutic against NSCLC.

The performance degradation at low temperatures and frequent safety accidents have aggravated security risks and inhibited the long-term service of lithium-ion batteries (LIBs). As a key component of LIBs, the separator has a great impact on the performance and safety of the battery. In this study, tensile tests of two commercial polyolefin separators (Celgard 2325 and Celgard PE) are performed under low-temperature and immersion conditions. Four representative temperature points and dimethyl carbonate [(DMC), the common solvent in electrolytes] are selected to investigate the coupling effect on the mechanical properties of the separators. The results show that both the separators have anisotropy, but the performance of Celgard 2325 varies more significantly than that of Celgard PE along different directions. Additionally, it is found that with a decrease in the temperature, the tensile strength of the two separators increases, while the elongation decreases. Electrolyte immersion induces a softening tendency in Celgard 2325. Due to the special effect of the residual electrolyte on polyethylene fibers, Celgard PE shows the opposite result. Furthermore, the effect of low temperature is revealed by the analysis of the crystallinity and molecular structure, which can be obtained by X-ray diffraction and Raman spectroscopy, respectively. In addition, the contact angle is measured to describe the wettability variation related to low temperature. The present work provides a theoretical basis and experimental data for the application and development of separators.

The numerous health benefits of olive oil are widely known, however, it also provides anti-allergic properties that have not yet been fully defined. In this study, the anti-allergic activity of olive oil was evaluated by analyzing the clinical symptoms and immune-related factors in BALB/c mice that had ingested 600 mg/(kg∙day) olive oil for two weeks prior to the evaluation. An allergy model was subsequently constructed for analysis, the results of which showed that the olive oil reduced the scores of allergic symptoms in the mice, and up-regulated the hypothermia and the decline in the immune organ index. Moreover, fewer allergy-related cytokines and reduced intestinal inflammation was discovered in the olive oil-treated group. In addition, analysis of intestinal mucosal immune-related factors revealed that the olive oil promoted the expression of intestinal tight junction proteins (Claudin-1, Occludin, and ZO-1) and IL-22, and helped maintain the integrity of the intestinal epithelial physical barrier. Increased levels of mucin 2 and β-defensin were also found in the intestinal mucus of the olive oil-treated mice. These findings suggest that the oral administration of olive oil effectively attenuated the ovalbumin-induced allergic immune response in the mice, and had a positive effect on intestinal epithelial mucosal immunity.

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The mechanical properties of battery materials under actual service conditions are crucial for the safety and durability of batteries, but specialized systems which are able to carry out in-situ low-temperature-mechanical coupling testing of battery materials are lacking. In this work, a low-temperature-mechanical coupling test system for battery materials is developed to investigate the mechanical properties of battery materials under low-temperature conditions. A semi-enclosed stable low-temperature loading unit is built by using high-power Peltier coolers and a double circulating water cooling system, which facilitates the observation of the changes in morphology and temperature of battery materials at different low temperatures. Based on the proposed double circulating water cooling system, a target temperature of −40 °C with maximum fluctuation lower than ±0.40 °C was realized within a rapid refrigeration time of 112 s. Through in-situ tensile tests of typical lithium-ion battery separators at temperatures in a range from −40 °C to 20 °C, the load-displacement response and the brittleness trend of the separators with the decrease of temperature are confirmed, which verify the low-temperature loading capacity and testing function of the proposed system. Compared with the separators at 20 °C, the strain to fracture and fracture energy under −40 °C decreased by 29.3% and 15.2%, respectively.

The evolution of mechanical properties of separators affected by temperature shifts is imperative for the performance of the lithium-ion battery. The flexible film characteristics hinder the evaluation of the micromechanical properties of separators. In the present study, considering the susceptibility of separators to temperature fluctuations, the temperature distribution of the battery during the discharging process at subzero temperature is obtained. Three sets of separator samples subjected to various temperature shifts are prepared. Through multicycle depth-sensitive nanoindentation, the temperature-dependent weakening of elastic modulus and hardness of separators is experimentally verified. Moreover, the variation trends of elastic modulus, hardness, and hysteresis response of the separator specimens in terms of temperature are investigated via extracting from the multicycle loading–unloading nanoindentation responses. The temperature-dependent variations in the elastic modulus of the separator were investigated by following heating, cooling, and thermostatic processes. Meanwhile, the indentation tests also verify that the effect of temperature shifts on the hardness exhibits an attenuation trend when heating or cooling is followed by a thermostatic process. The variation analysis of nanoindentation hardness as a function of temperature shifts shows typical size effects dependent on the nanoindentation depth. The temperature-induced residual stress and elemental distribution are also analyzed through characterization using X-ray diffraction and energy-dispersive X-ray spectroscopy, respectively. The obtained evolution law of temperature shift-induced mechanical properties of a separator could facilitate the optimal design of the separators and provide the supporting data to enhance the safety performance of lithium-ion batteries.

The self-pierce riveting process for alloy materials has a wide range of applications in the automotive manufacturing industry. This will not only affect the operation performance but also cause accidents in severe cases when there are defects in the riveted parts. A deep learning detection model is proposed that integrates atrous convolution and dynamic convolution to identify defects of self-piercing riveting parts efficiently to overcome the problem in quality inspection after the body self-piercing riveting process. First, a backbone network for extracting riveting defect features is constructed based on the ResNet network. Second, the center area of each riveting defect is located preferentially by the center point detection algorithm. Finally, the bounding box of riveting defects is regressed to achieve defect detection based on this central region. Among them, atrous convolution is used in the external network to increase the receptive field of the model, which combined with an active convolution so that a dynamic atrous convolution module is designed. This module is used to enhance the correlation between feature points of individual pixel in the image, which helps to identify defects with incomplete image edges and suppress background interference. Ablation experiments show that the proposed method achieves the highest accuracy of 96.3%, which is 3.9% higher than the original method. It is found that the proposed method is less affected by the background interference from the qualitative comparison. Moreover, it can also effectively identify the riveting defects on the surface of each area.

Photodynamic therapy (PDT) is a promising approach to cancer therapy. However, the relatively short tumor retention time of photosensitizers (PSs) makes it difficult to catch the optimal treatment time and restricts multiple PDT within a single injection. In this study, a tumor‐specific phototheranostic nanomedicine (DPPa NP) is developed for photodynamic/chemo combination therapy with a prolonged PDT treatment window. DPPa NP is prepared via encapsulating a hydrophobic oxidized bovine serum albumin (BSA‐SOH)‐conjugatable PS DPPa with amphiphilic H2O2‐activatable chlorambucil (CL) prodrug mPEG‐TK‐CL. The released CL under H2O2treatment can not only kill tumor cells but also upregulate reactive oxygen species levels within tumor cells, leading to the almost full release of cargoes. The released DPPa may conjugate with overexpressed BSA‐SOH, which results in the recovery of the fluorescence signal and photodynamic effect. More importantly, such conjugation transfers DPPa from a small molecule PS into a macromolecular PS with a long tumor retention time and treatment window of PDT, which enables multiple PDT. This study thus provides an effective strategy to prolong the treatment window of PDT and enables tumor‐specific fluorescence imaging‐guided combination therapy. A nanophotosensitizer which can prolong the treatment window of photodynamic therapy is developed. The intracellular H2O2can trigger the release of both chlorambucil (CL) and 3,5‐dioxocyclohexanecarboxylic acid (DHCA)‐functionalized pyropheophorbide a (DPPa). CL can trigger a self‐amplification effect to accelerate the dissociation of nanoparticles, while DPPa can bind with oxidized bovine serum albumin to enhance its photodynamic efficacy and prolong the treatment window.

Oligo-crystals contain only a few crystalline grains and are often used in the fields of micro-electromechanics, turbine blades and shape memory alloys. To date, there has not been any study on the ultrasonic evaluation of oligo-crystals. In this work, we modeled the microstructure of oligo-crystalline copper foil using the phase field method, and carried out a finite element analysis of the oligo-crystal. Data were generated through multiple simulations and the data were analyzed statistically to assess the effects of ultrasonic testing configuration, the size of the transducer aperture, the types of texture, and the internal flaws on the propagation and scattering characteristics of ultrasonic waves. The results showed that the majority of conventional ultrasonic evaluation techniques failed to work for oligo-crystals. Firstly, ultrasonic velocity and attenuation coefficient in a given oligo-crystal are not constant when measured in different ultrasonic configurations and with different aperture sizes. Secondly, oligo-crystals are characterized by a rather low level of grain noise, possibly due to the low density of grain boundary. Thirdly, for a side drilled hole of a given size and depth in an oligo-crystal, the simulated amplitude and time-of-flight of flaw echoes are highly variable, which makes flaw location and flaw sizing very difficult. More in-depth research on physical modeling and experimental verification of ultrasonic testing are clearly needed for oligo-crystals in the future. • Phase field method is used to create oligo-crystals for ultrasonic simulation. • Oligo-crystals do not possess constant ultrasonic velocity and attenuation. • Almost no grain noise is generated in oligo-crystals. • Ultrasonic flaw location and flaw sizing will be difficult in oligo-crystals. • Conventional ultrasonic evaluation tools fail to function in oligo-crystals. [ABSTRACT FROM AUTHOR]