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Aflatoxin B1 (AFB1), a mycotoxin commonly found in foodstuffs, poses significant health risks when ingested through contaminated food sources. Therefore, it is imperative to devise a safe and efficient method for AFB1 degradation. Graphitic carbon nitride (g-C3N4) stands out as an exceptionally stable, non-toxic, and economical photocatalyst, which is widely used in photocatalysis. In this study, we explored the photocatalytic performance of four g-C3N4 catalysts derived from different precursors (dicyandiamide (D-CN), melamine (M-CN), thiourea (T-CN), and urea (U-CN)) in AFB1 degradation under visible light. Notably, the U-CN catalyst displayed an impressive degradation rate of 93.5% for AFB1 within 30 min, outperforming M-CN (82.5%), T-CN (78.5%), and D-CN (46.2%). This superior performance is attributed to its inherent porous structure, enlarged specific surface area, and reduced electron–hole pairs' recombination rate. Additionally, our investigation identified ˙O2− as the primary active species in AFB1 degradation. Furthermore, we explored the degradation pathway of AFB1 and its associated inactivation mechanism mediated by the U-CN catalyst. This work provides a theoretical foundation for developing highly efficient photocatalysts in AFB1 degradation. [ABSTRACT FROM AUTHOR]

Finding efficient photocatalysts is the key to achieving sustainable hydrogen production. In this work, a rational design of Cd2+-doped Zn3In2S6 (ZIS) and a heterojunction structure with g-C3N4 (GCN) was carried out to form a GCN/Cd/ZIS composite. The synergistic effect of Cd2+ doping and heterojunction construction in the photocatalytic hydrogen production process was probed. The results showed that doping Cd2+ modified the bandgap structure of ZIS and improved the photocatalytic activity. The heterojunction construction between Cd/ZIS and GCN also effectively promoted the separation and migration of photogenerated carriers, which significantly improved the hydrogen production performance of the GCN/Cd/ZIS composite. The hydrogen production rate of 15% Cd/ZIS and 5% GCN/Cd/ZIS was 2.45 mmol g−1 h−1, 3.34 mmol g−1 h−1, which was 4.3 and 5.9 times higher than that of ZIS (0.57 mmol g−1 h−1), respectively. This study provides strong evidence that doping and heterojunction construction can synergistically improve photocatalytic activity. [ABSTRACT FROM AUTHOR]

This study aims to create a pediatric head injury database based on cranial CT examinations and explore their epidemiologic characteristics. Data related to cranial CT examinations of pediatric head injuries from March 2014 to March 2021 were collected at outpatient and emergency department of a pediatric medical center. The causes of injury, observable post-injury symptoms, and cranial injury findings were extracted with the assistance of natural language processing techniques. Reviewing the data from records on 52,821 children with head injuries over a period of 7 years, the most common causes of pediatric head injury were falls (58.3%), traffic accidents (26.0%), smash/crush/strike (13.9%), violence (1.5%) and sports-related incidents (0.3%). Overall, most of those injured were boys which accounting for 62.2% of all cases. Skull fractures most commonly occur in the parietal bone (9.0%), followed by the occipital (5.2%), frontal (3.3%) and temporal bones (3.0%). Most intracranial hemorrhages occurred in epidural (5.8%), followed by subdural (5.1%), subarachnoid (0.9%), intraparenchymal (0.5%) and intraventricular (0.2%) hemorrhages. Spring and autumn showed more events than any other season. To the best of our knowledge, this is the largest sample of epidemiological study of head injury in the Chinese pediatric population to date. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) is a high-resolution imaging radar. With the deteriorating electromagnetic environment, SAR systems are susceptible to various forms of electromagnetic interference, including deception jamming. This jamming notably impacts SAR signal processing and subsequently worsens the quality of acquired images. Chaotic frequency modulation (CFM) signals could effectively counteract deception jamming. Nevertheless, due to the inadequate band-limited performance of CFM signals, higher oversampling factors are needed for achieving optimal low sidelobe levels, leading to increased system costs and excessively high data rates. Additionally, not all chaotic sentences meet the CFM signal requirements. In response, this paper proposes a novel signal modulation method called chaotic-nonlinear frequency modulation (C-NLFM) that enhances band-limited performance. The optimum parameters for C-NLFM signals are selected using the particle swarm optimization (PSO) algorithm. In this way, C-NLFM signals attain ideal low sidelobe levels even when faced with reduced oversampling factors. Meanwhile, this chaotic coding mode retains its capability to effectively suppress deception jamming. Moreover, C-NLFM signals demonstrate versatility in adapting to various chaotic sequences, thereby enhancing their flexibility to modify the signals as required. Through comprehensive simulations, data analysis, and a semi-physical experiment, the effectiveness and superiority of this proposed method have been confirmed. [ABSTRACT FROM AUTHOR]

Deep-sea eukaryotic microorganisms play a vital role in degrading organic matter and geochemically cycling elements in the deep ocean. However, the impact of sampling methods on detection of these microorganisms under high hydrostatic pressure remains uncertain. In this study, we compared a traditional water sampling method using a Niskin bottle, an in situ microbial filtration and fixation method (ISMIFF), and a multiple in situ nucleic acid collection (MISNAC) method to exhibit differences in the community structures that were collected at ~590–3100 m in the South China Sea (SCS). The classification and biodiversity indices of 18S rDNA Illumina sequencing reads from the V9 variation region revealed higher diversity for MISNAC DNA absorption column samples compared to others. Importantly, the relative abundance of Ciliophora (19.49%), Copepoda (23.31%), and Diplonemea (10.67%) was higher in MISNAC adsorption column samples, while Retaria (48.86%) were dominant in the MISNAC membrane samples. This indicates that MISNAC columns might collect more DNA in situ for the naked protists, while Retaria with a carbonate shell were more likely retained on the membrane. In conclusion, MISNAC is an effective method for DNA collection of deep-sea eukaryotic microorganisms and provides valuable materials for studying deep-sea microbial ecosystems. [ABSTRACT FROM AUTHOR]