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Aiming at the problem of low detection accuracy caused by overlapping occlusion and noise disturbance, a contraband detection algorithm for X‐ray security inspection images based on global semantic enhancement is proposed to achieve accurate contraband target detection by enhancing global semantic information. First, the disturbance suppression module is used to weaken the noise disturbance at different positions by local suppression and aggregate finer detail information. Then, the parallel cascade search module is used to capture long‐range dependencies and strengthen the representation of global semantic information, which helps the model identify contraband under overlapping occlusion. Finally, the contribution of different features is adaptively adjusted through the feature‐weighted fusion module, which promotes the effective fusion of multi‐scale features and improves the accuracy of model detection. The method in this article has been extensively evaluated and experimented on three mainstream benchmark datasets: SIXray, OPIXray, and PIDray. The mAPs of three datasets reach 93.5%, 91.9%, and 85.9%, respectively. The experimental results fully demonstrate that the method in this article has better performance compared with the latest method, which can meet the practical application requirements of real‐time target detection. [ABSTRACT FROM AUTHOR]

The dispersion of nano‐SiO2 (NS) in cement plays a critical role in enhancing the properties of cementitious materials. In this study, the combination of ultrasonic dispersion and polycarboxylic acid water reducing agent (PCE) was used to significantly improve the dispersion of NS. The effects of ultrasonic dispersion time, NS content, and PCE content on dispersion quality were investigated, alongside their impact on mechanical properties, electrical resistivity, and frost resistance. The results demonstrated that this synergistic method optimized the dispersion of NS, leading to superior mechanical properties and frost resistance. With an ultrasonic dispersion time of 40 min, NS content of 1.0 wt.%, and PCE content of 0.75 wt.%, the cement paste achieved its optimal performance. Compared to non‐dispersed samples, compressive strength increased by 33.7%. After 75 freeze–thaw cycles, the mass loss was 2%, the relative dynamic elastic modulus was 99.15%, and the strength loss was 13.74%. [ABSTRACT FROM AUTHOR]

The recent COVID-19 pandemic has once again caught the attention of people on the probable zoonotic transmission from animals to humans, but the role of companion animals in the coronavirus (CoV) epidemiology still remains unknown. The present study was aimed to investigate epidemiology and molecular characterizations of CoVs from companion animals in Chengdu city, Southwest China. 523 clinical samples from 393 animals were collected from one veterinary hospital between 2020 and 2021, and the presence of CoVs was detected by end-point PCR using pan-CoV assay targeting the RdRp gene. Partial and complete S genes were sequenced for further genotyping and genetic diversity analysis. A total of 162 (31.0%, 162/523) samples and 146 (37.2%, 146/393) animals were tested positive for CoVs. The positive rate in rectal swabs was higher than that in eye/nose/mouth swabs and ascitic fluid but was not statistically different between clinically healthy and diseased ones. Genotyping identified twenty-two feline enteric coronavirus (FCoV) I, four canine enteric coronavirus (CECoV) I, fourteen CECoV IIa, and one CECoV IIb, respectively. Eight complete S genes, including one canine respiratory coronavirus (CRCoV) strain, were successfully obtained. FCoV strains (F21071412 and F21061627) were more closely related to CECoV strains than CRCoV, and C21041821-2 showed potential recombination event. In addition, furin cleavage site between S1 and S2 was identified in two strains. The study supplemented epidemiological information and natural gene pool of CoVs from companion animals. Further understanding of other functional units of CoVs is needed, so as to contribute to the prevention and control of emerging infectious diseases. [ABSTRACT FROM AUTHOR]

Salmonella enterica serotype Enteritidis (SE) is a primary pathogen that causes foodborne diseases in humans. Although whole‐genome sequencing (WGS) ‐based typing analyses have been increasingly used to investigate food‐poisoning outbreaks, they are rarely applied to the epidemiology of multiple Salmonella outbreaks in Sichuan, China. This study therefore isolated SE from patients and food of two consecutive food‐poisoning outbreaks during 2020 in Sichuan, China. We tracked outbreak origin using epidemiological investigation, serotyping, antimicrobial susceptibility testing (AST), pulsed‐field gel electrophoresis (PFGE), and WGS. We also determined phylogenetic relationships using PFGE, whole and core genome multilocus sequence typing (wg/cgMLST), and whole‐genome single nucleotide polymorphism (wgSNP) analyses. Epidemiological investigations identified a correlation between cake consumption and food poisoning. Thirteen strains isolated from patients and one strain isolated from the cake were confirmed as SE. Among the 14 strains, only six shared the same AST pattern (AMP‐AMS‐Sul‐STR). Isolates from patients and cakes were indistinguishable in PFGE results. All four methods, namely PFGE, wgMLST, cgMLST, and wgSNP were appropriate for bacterial typing in SE‐related outbreak investigation. However, wgSNP can assign 12 SE strains from the first outbreak to one cluster and assign two SE strains from the second outbreak to another cluster, while PFGE, wgMLST, cgMLST did not successfully distinguish the SE strains from different outbreaks. Thus, we conclude that SNP‐based phylogenetic analysis might be a viable method for differentiating SE strains at the outbreak level. [ABSTRACT FROM AUTHOR]

In this paper, Ag-TiO2 photocatalysts with different Ag contents (1 mol%–5 mol%) were prepared and applied to cement mortar. The photocatalytic performance of Ag-TiO2 and photocatalytic cement mortar under UV light and simulated solar light was evaluated. The results showed that Ag loading on the surface of TiO2 could reduce its band gap width and increase its absorbance in the visible region, and 2% Ag-TiO2 had the highest photocatalytic activity under UV light, the degradation rate of methyl orange (MO) was 95.5% at 30 min, and the first-order reaction constant k was 0.0980 min−1, which was 61.7% higher than that of TiO2, and 5% Ag-TiO2 had the highest photocatalytic activity under solar light, the degradation rate of methylene blue (MB) was 69.8% at 40 min, and the first-order reaction constant k was 0.0294 min−1, which was 90.9% higher than that of TiO2. The photocatalytic mortar prepared by the spraying method has high photocatalytic performance, The MO degradation rate of sample S2 under UV light was 87.5% after 120 min, MB degradation rate of sample S5 under solar light was 75.4% after 120 min. The photocatalytic reaction conforms to the zero-order reaction kinetics, which was 1.5 times–3.3 times higher than that of the mixed samples and has no effect on the mechanical properties of mortar. [ABSTRACT FROM AUTHOR]