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Abstract Identifying the ash accumulation generated on the water-cooled walls of the waste incinerator is essential for the cleanup by the robotic arm. This paper improves a new algorithm based on YOLOv8n, which can identify the ash accumulation position on the water-cooled wall quickly and accurately. Firstly, the multi-scale fusion image enhancement algorithm is used to improve the sharpness and contrast of the image and enrich the details of the image. Secondly, the backbone feature extraction network of YOLOv8n is replaced by Mobilenetv3 network, which reduces the parameters in the model greatly. Finally, this paper improves a new attention mechanism AWGAM (Add Weight Global Attention Mechanism) based on GAM (Global Attention Mechanism), which can better integrate the feature information between different dimensions and improve the learning ability of the model. AWGAM is added to the backbone of the model. The experimental results show that compared with the original YOLOv8n model, the improved YOLOv8n model has 59.9% fewer parameters, 4.4% higher precision, 8.8% higher recall, 3.2% higher mAP50 (mean Average Precision) and 8.8% higher mAP50-95. This model has made remarkable progress on the basis of the original algorithm, and has strong competitiveness compared with other advanced target detection models. The lightweight and high accuracy of ash accumulation detection offered by the proposed model presents promising applications in ash accumulation detection tasks of water-cooled walls.

Rapid urbanization in the Asia-Pacific region is expected to place two-thirds of its population in concrete-dominated urban landscapes by 2050. While diverse architectural facades define the unique appearance of these urban systems. There remains a significant gap in our understanding of the composition, assembly, and ecological potential of microbial communities on building exteriors. Here, we examined bacterial and protistan communities on building surfaces along an urbanization gradient (urban, suburban and rural regions), investigating their spatial patterns and the driving factors behind their presence. A total of 55 bacterial and protist phyla were identified. The bacterial community was predominantly composed of Proteobacteria (33.7% to 67.5%). The protistan community exhibited a prevalence of Opisthokonta and Archaeplastida (17.5% to 82.1% and 1.8% to 61.2%, respectively). The composition and functionality of bacterial communities exhibited spatial patterns correlated with urbanization. In urban buildings, factors such as facade type, light exposure, and building height had comparatively less impact on bacterial composition compared to suburban and rural areas. The highest bacterial diversity and lowest Weighted Average Community Identity (WACI) were observed on suburban buildings, followed by rural buildings. In contrast, protists did not show spatial distribution characteristics related to facade type, light exposure, building height and urbanization level. The distinct spatial patterns of protists were primarily shaped by community diffusion and the bottom-up regulation exerted by bacterial communities. Together, our findings suggest that building exteriors serve as attachment points for local microbial metacommunities, offering unique habitats where bacteria and protists exhibit independent adaptive strategies closely tied to the overall ecological potential of the community.

Exposure to ionizing radiation leads to oxidative damages in living cells. NADPH provides the indispensable reducing power to regenerate the reduced glutathione to maintain cellular redox equilibria. In mammalian cells, pentose phosphate pathway (PPP) is the major route to produce NADPH by using glycolytic intermediates, and the rate-limiting step of PPP is controlled by glucose-6-phosphate dehydrogenase (G6PD). Nevertheless, whether G6PD is timely co-opted under ionizing radiation to cope with oxidative stress remains elusive. Here we show that cellular G6PD activity is induced 30 min after ionizing radiation, while its protein expression is mostly unchanged. Mechanistically, casein kinase 2 (CK2) phosphorylates G6PD T145 under ionizing radiation, which consolidates the enzymatic activity of G6PD by facilitating G6PD binding with its substrate NADP+. Further, CK2-dependent G6PD T145 phosphorylation promotes NADPH production, decreases ROS level and supports cell proliferation under ionizing radiation. Our findings report a new anti-oxidative signaling route under ionizing radiation, by which CK2-mediated rapid activation of G6PD orchestrates NADPH synthesis to maintain redox homeostasis, thereby highlighting its potential value in the early treatment of ionizing radiation-induced injuries.

In this letter, a high performance quasi-vertical GaN-on-Si Schottky barrier diode (SBD) was fabricated by combing in-situ p-GaN layer with hydrogen plasma treatment and controlled diffusion as edge terminations (ETs), where the main junction region of Schottky contact is emerged by pattern etching the top p-GaN layer. The p-n junction with higher barrier height can screen the Schottky contact from high electric field induced by field crowding effect. The hydrogen plasma treatment and controlled diffusion applied to the p-GaN layer further reduces the electric field crowding effect near the p-n junction edge via a gradient junction termination extension structure. As a result, the breakdown voltage of the edge p-GaN terminated SBD with H treatment and diffusion is significantly boosted from 140 V in conventional SBD to 500 V with optimized fabrication process. The on/off current ratio of the diode is as high as 1011@±3 V. The forward current density is 1.45 kA/cm2@3 V and the specific on-resistance is 1.57 $\text{m}\Omega \cdot $ cm2.

IntroductionSepsis is a common but serious disease in intensive care units, which may induce multiple organ dysfunctions such as liver injury. Previous studies have demonstrated that gamma delta (γδ) T cells play a protective role in sepsis. However, the function and mechanism of γδ T cells in sepsis-induced liver injury have not been fully elucidated. IL-17A-producing γδ T cells are a newly identified cell subtype.MethodsWe utilized IL-17A-deficient mice to investigate the role of IL-17A-producing γδ T cells in sepsis using the cecum ligation and puncture (CLP) model.ResultsOur findings suggested that these cells were the major source of IL-17A and protected against sepsis-induced liver injury. Flow cytometry analysis revealed that these γδ T cells expressed Vγ4 TCR and migrated into liver from peripheral post CLP, in a CCR6-dependent manner. When CLP mice were treated with anti-CCR6 antibody to block CCR6-CCL20 axis, the recruitment of Vγ4+ γδ T cells was abolished, indicating a CCR6-dependent manner of migration. Interestingly, pseudo germ-free CLP mice treated with antibiotics showed that hepatic IL-17A+ γδ T cells were regulated by gut commensal microbes. E. coli alone were able to restore the protective effect in pseudo germ-free mice by rescuing hepatic IL-17A+ γδ T cell population.ConclusionOur research has shown that Vγ4+ IL-17A+ γδ T cells infiltrating into the liver play a crucial role in protecting against sepsis-induced liver injury. This protection was contingent upon the recruitment of CCR6 and regulated by gut commensal microbes.

PbSn solders are used in semiconductor devices for aerospace or military purposes with high levels of reliability requirements. Microalloying has been widely adopted to improve the reliability for Pb-free solders, but its application in PbSn solders is scarce. In this article, the optimization of PbSn solder reliability with Ge microalloying was investigated using both experimental and calculation methods. Intermetallic compounds (IMC) growth and morphologies evolution during reliability tests were considered to be the main factors of device failure. Through first-principle calculation, the growth mechanism of interfacial Ni3Sn4 was discussed, including the formation of vacancies, the Ni-vacancies exchange diffusion and the dominant Ni diffusion along the [1 0 0] direction. The doping of Ge in the cell increased the exchange energy barrier and thus inhibited the IMC development and coarsening trend. In three reliability tests, only 0.013 wt% Ge microalloying in Pb60Sn40 was able to reduce IMC thickness by an increment of 22.6~38.7%. The proposed Ge microalloying method in traditional PbSn solder could yield a prospective candidate for highly reliable applications.

In this study, the physical properties of F ion-implanted GaN were thoroughly studied, and the related electric-field modulation mechanisms in ion-implanted edge termination were revealed. Transmission electron microscopy results indicate that the ion-implanted region maintains a single-crystal structure even with the implantation of high-energy F ions, indicating that the high resistivity of the edge termination region is not induced by amorphization. Alternately, ion implantation-induced deep levels could compensate the electrons and lead to a highly resistive layer. In addition to the bulk effect, the direct bombardment of high-energy F ions resulted in a rough and nitrogen-deficient surface, which was confirmed via atomic force microscopy (AFM) and X-ray photoelectron spectroscopy. The implanted surface with a large density of nitrogen vacancies can accommodate electrons, and it is more conductive than the bulk in the implanted region, which is validated via spreading resistance profiling and conductive AFM measurements. Under reverse bias, the implanted surface can spread the potential in the lateral direction, whereas the acceptor traps capture electrons acting as space charges, shifting the peak electric field into the bulk region in the vertical direction. As a result, the Schottky barrier diode terminated with high-energy F ion-implanted regions exhibits a breakdown voltage of over 1.2 kV.

Hypoxia induces mitochondrial clearance and autophagy, although the upstream mechanisms are not well defined. Here, the authors identify that oxygen-sensitive methylation of the key autophagy regulator ULK1 promotes ULK1 activation and subsequent autophagosome formation and mitochondrial clearance.

Acoustic dyadic sensors (ADSs) are a new type of acoustic sensor with higher directivity than microphones and acoustic vector sensors, which has great application potential in the fields of sound source localization and noise cancellation. However, the high directivity of an ADS is seriously affected by the mismatches between its sensitive units. In this article, (1) a theoretical model of mixed mismatches was established based on the finite-difference approximation model of uniaxial acoustic particle velocity gradient and its ability to reflect the actual mismatches was proven by the comparison of theoretical and experimental directivity beam patterns of an actual ADS based on MEMS thermal particle velocity sensors. (2) Additionally, a quantitative analysis method based on directivity beam pattern was proposed to easily estimate the specific magnitude of the mismatches, which was proven to be useful for the design of ADSs to estimate the magnitudes of different mismatches of an actual ADS. (3) Moreover, a correction algorithm based on the theoretical model of mixed mismatches and quantitative analysis method was successfully demonstrated to correct several groups of simulated and measured beam patterns with mixed mismatches.