The mechanical characteristics of an aluminum foam winding CFRP composite structure under axial compression.

To enhance the energy absorption properties of the energy-absorbing structure, carbon fiber-reinforced polymer (CFRPs) with higher specific energy absorption and porous material aluminum foam with better compressive characteristics were organically combined, and a lighter aluminum foam winding carbon fiber-reinforced polymer structure (CFRP-FA-FW) was designed. Through quasi-static compression testing, the deformation mode and energy absorption properties of CFRP-FA-FW under axial load were examined. The energy absorption and specific energy absorption of CFRP-FA-FW are both increased by 113.55 % and 60.73 %, respectively, compared to the simple composite structure CFRP-FA. Finite element simulation was used for the parametric analysis of the CFRP-FA-FW structure to assess the effects of the relative density of the aluminum foam, the fiber lay-up angle, and the thickness. The results reveal that the change in the relative density of aluminum foam has little impact on the failure deformation mode of CFRP-FA-FW under axial load; the structure has a higher energy absorption capacity and a smoother energy absorption process when the fiber lay-up angle is [0°/90°]ns and [45°]ns; the energy absorption capacity of CFRP-FA-FW is significantly improved by increasing the thickness of the carbon fiber lay-up, and the procedure is also more efficient.

High Overexpression of SiAAP9 Leads to Growth Inhibition and Protein Ectopic Localization in Transgenic Arabidopsis.

Amino acid permeases (AAPs) transporters are crucial for the long-distance transport of amino acids in plants, from source to sink. While Arabidopsis and rice have been extensively studied, research on foxtail millet is limited. This study identified two transcripts of SiAAP9, both of which were induced by NO3- and showed similar expression patterns. The overexpression of SiAAP9L and SiAAP9S in Arabidopsis inhibited plant growth and seed size, although SiAAP9 was found to transport more amino acids into seeds. Furthermore, SiAAP9-OX transgenic Arabidopsis showed increased tolerance to high concentrations of glutamate (Glu) and histidine (His). The high overexpression level of SiAAP9 suggested its protein was not only located on the plasma membrane but potentially on other organelles, as well. Interestingly, sequence deletion reduced SiAAP9's sensitivity to Brefeldin A (BFA), and SiAAP9 had ectopic localization on the endoplasmic reticulum (ER). Protoplast amino acid uptake experiments indicated that SiAAP9 enhanced Glu transport into foxtail millet cells. Overall, the two transcripts of SiAAP9 have similar functions, but SiAAP9L shows a higher colocalization with BFA compartments compared to SiAAP9S. Our research identifies a potential candidate gene for enhancing the nutritional quality of foxtail millet through breeding.

Automatic detection of the third molar and mandibular canal on panoramic radiographs based on deep learning.

PURPOSE: This study aims to develop a deep learning framework for the automatic detection of the position relationship between the mandibular third molar (M3) and the mandibular canal (MC) on panoramic radiographs (PRs), to assist doctors in assessing and planning appropriate surgical interventions. METHODS: Datasets D1 and D2 were obtained by collecting 253 PRs from a hospitals and 197 PRs from online platforms. The RPIFormer model proposed in this study was trained and validated on D1 to create a segmentation model. The CycleGAN model was trained and validated on both D1 and D2 to develop an image enhancement model. Ultimately, the segmentation and enhancement models were integrated with an object detection model to create a fully automated framework for M3 and MC detection in PRs. Experimental evaluation included calculating Dice coefficient, IoU, Recall, and Precision during the process. RESULTS: The RPIFormer model proposed in this study achieved an average Dice coefficient of 92.56 % for segmenting M3 and MC, representing a 3.06 % improvement over the previous best study. The deep learning framework developed in this research enables automatic detection of M3 and MC in PRs without manual cropping, demonstrating superior detection accuracy and generalization capability. CONCLUSION: The framework developed in this study can be applied to PRs captured in different hospitals without the need for model fine-tuning. This feature is significant for aiding doctors in accurately assessing the spatial relationship between M3 and MC, thereby determining the optimal treatment plan to ensure patients' oral health and surgical safety.

Simulation research on aerodynamic noise characteristics of a compressor under different working conditions.

The shear stress transport turbulence model is employed to conduct a detailed study of flow characteristics at the highest efficiency point and near-stall point in a full-channel 1.5-stage compressor in this paper. The simulation results for the compressor's total pressure ratio and efficiency exhibit good agreement with experimental data. Emphasis is placed on examining the internal flow structure in the tip area of the compressor rotor under near-stall conditions. The results reveal that significant differences in flow structure primarily occur in the tip area as the compressor approaches stall. Specifically, a reduction in turbulent kinetic energy is observed in a region spanning approximately 20%-60% of the chord length on the rotor suction face near-stall conditions. Two additional peak frequencies, at 0.8 and 1.6 times the blade passage frequency, are observed, and the intricate flow phenomena are elaborated at the near-stall point. The near-stall point exhibits greater noise levels than the highest efficiency point, where the intensity of the surface source increases by more than 10 dB, peaking at 20 dB. This additional peak serves as a significant supplementary noise source near the stall point, leading to a maximum increase of 33.3 dB in the free radiated sound power. The acoustic response within the duct indicates that the compressor operating at the near-stall point continues to produce substantial noise on the actual test bench, showing an average increase of 6 dB in noise levels, and the distribution of the additional peak single-tone noise at the entrance significantly differs from that observed at the highest efficiency point.

Reactive oxygen species (ROS) modulate nitrogen signaling using temporal transcriptome analysis in foxtail millet.

Reactive oxygen species (ROS) is a chemically reactive chemical substance containing oxygen and a natural by-product of normal oxygen metabolism. Excessive ROS affect the growth process of crops, which will lead to the decrease of yield. Nitrogen, as a critical nutrient element in plants and plays a vital role in plant growth and crop production. Nitrate is the primary nitrogen source available to plants in agricultural soil and various natural environments. However, the molecular mechanism of ROS-nitrate crosstalk is still unclear. In this study, we used the foxtail millet (Setaria italica L.) as the material to figure it out. Here, we show that excessive NaCl inhibits nitrate-promoted plant growth and nitrogen use efficiency (NUE). NaCl induces ROS accumulation in roots, and ROS inhibits nitrate-induced gene expression in a short time. Surprisingly, low concentration ROS slight promotes and high concentration of ROS inhibits foxtail millet growth under long-term H2O2 treatment. These results may open a new perspective for further exploration of ROS-nitrate signaling pathway in plants.

Mobile phone addiction and academic burnout: the mediating role of technology conflict and the protective role of mindfulness.

With the rapid development of Internet technology, more and more college students are facing the threat of mobile phone addiction. However, the relationship and underlying mechanism between mobile phone addiction and academic burnout haven't been explored in depth. This study proves the mediating role of technology conflict and the moderating role of mindfulness in the relation between mobile phone addiction and academic burnout. 752 college students were recruited to complete the questionnaire of mobile phone addiction, technology conflict, mindfulness and academic burnout. Results showed that mobile phone addiction was significantly and positively associated with academic burnout, and this relationship could be mediated by technology conflict. Besides, the direct effect of mobile phone addiction on academic burnout and the indirect effect of technology conflict in this link were moderated by mindfulness. Both these two effects are stronger for college students with lower level of mindfulness. Our findings enrich our understanding of how and when mobile phone addiction was related to academic burnout. Educational professionals and parents should take timely measure to the academic burnout of college students suffering from mobile phone addiction, particularly for those with lower level of mindfulness.

Amorphous/crystalline RhFeP metallene for hydrazine-assisted water splitting.

Replacing the slow oxygen evolution reaction with favorable hydrazine oxidation reaction (HzOR) is a green and efficient way to produce hydrogen. In this work, we synthesize amorphous/crystalline RhFeP metallene via phase engineering and heteroatom doping. RhFeP metallene has good catalytic activity and stability for HER and HzOR, and only an ultralow voltage of 18 mV is required to achieve 10 mA cm-2in a two-electrode hydrazine-assisted water splitting system. The superior result is mainly ascribed to the co-doping of Fe and P and the formation of amorphous/crystalline RhFeP metallene with abundant phase boundaries, thereby adjusting electronic structure and increasing active sites.

Structural insights into the Oryza sativa cation transporters HKTs in salt tolerance.

The high-affinity potassium transporters (HKTs), selectively permeable to either Na+ alone or Na+/K+, play pivotal roles in maintaining plant Na+/K+ homeostasis. Although their involvement in salt tolerance is widely reported, the molecular underpinnings of Oryza sativa HKTs remain elusive. In this study, we elucidate the structures of OsHKT1;1 and OsHKT2;1, representing two distinct classes of rice HKTs. The dimeric assembled OsHKTs can be structurally divided into four domains. At the dimer interface, a half-helix or a loop in the third domain is coordinated by the C-terminal region of the opposite subunit. Additionally, we present the structures of OsHKT1;5 salt-tolerant and salt-sensitive variants, a key quantitative trait locus associated with salt tolerance. The salt-tolerant variant of OsHKT1;5 exhibits enhanced Na+ transport capability and displays a more flexible conformation. These findings shed light on the molecular basis of rice HKTs and provide insights into their role in salt tolerance.

Interstitial Boron-Modulated Porous Pd Nanotubes for Ammonia Electrosynthesis.

Electrochemical conversion of nitrogen into ammonia at ambient conditions as a sustainable approach has gained significant attention, but it is still extremely challenging to simultaneously obtain a high faradaic efficiency (FE) and NH3 yield. In this work, the interstitial boron-doped porous Pd nanotubes (B-Pd PNTs) are constructed by combining the self-template reduction method with boron doping. Benefiting from distinctive one-dimensional porous nanotube architectonics and the incorporation of the interstitial B atoms, the resulting B-Pd PNTs exhibit high NH3 yield (18.36 µg h-1 mgcat.-1) and FE (21.95%) in neutral conditions, outperforming the Pd/PdO PNTs (10.4 µg h-1 mgcat.-1 and 8.47%). The present study provides an attractive method to enhance the efficiency of the electroreduction of nitrogen into ammonia by incorporating interstitial boron into porous Pd-based catalysts.

Degradation and translation of maternal mRNA for embryogenesis.

Maternal mRNAs accumulate during egg growth and must be judiciously degraded or translated to ensure successful development of mammalian embryos. In this review we integrate recent investigations into pathways controlling rapid degradation of maternal mRNAs during the maternal-to-zygotic transition. Degradation is not indiscriminate, and some mRNAs are selectively protected and rapidly translated after fertilization for reprogramming the zygotic genome during early embryogenesis. Oocyte specific cofactors and pathways have been illustrated to control different futures of maternal mRNAs. We discuss mechanisms that control the fate of maternal mRNAs during late oogenesis and after fertilization. Issues to be resolved in current maternal mRNA research are described, and future research directions are proposed.

Comparison of the effects of different artificial discs on hybrid surgery: A finite element analysis.

In recent years, artificial cervical discs have been used in intervertebral disc replacement surgery and hybrid surgery (HS). The advantages and disadvantages of different artificial cervical discs in artificial cervical disc replacement surgery have been compared. However, few scholars have studied the biomechanical effects of various artificial disc prostheses on the human cervical spine in HS which include the Anterior Cervical Discectomy and Fusion (ACDF) and Cervical Disc Arthroplasty (CDA). This study compared the biomechanical behavior of Mobi-C and Prestige LP in the operative and adjacent segments during two-level hybrid surgery. A three-dimensional finite element model of C2-C7 was first established and validated. Subsequently, clinical surgery was then simulated to establish a surgical model of anterior cervical fusion at the C4-C5 level. Mobi-C and Prestige-LP artificial disc prostheses were implanted at the C5-C6 level to create two hybrid models. All finite element models were fixed on the lower endplate of the C7 vertebra and subjected to a load of 73.6 N and different directions of 1 Nm torque on the odontoid process of the C2 vertebra to simulate human flexion, extension, lateral bending, and axial rotation. This paper compares the ROM, intervertebral pressure, and facet joint force after hybrid surgery with the intact model. The results show that compared with Prestige LP, Mobi-C can improve ROM of the replacement segment and compensate for the intervertebral pressure of the adjacent segment more effectively, but the facet joint pressure of the replacement segment may be higher.