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Thermomechanical treatment T10 (extension twinning + aging treatment) can largely enhance the precipitation strengthening effect of magnesium alloys. In this study, dislocation structure evolution and precipitation behavior during T10 treatment of an AZ80 extruded bar were analyzed mainly by two-beam diffraction in TEM. At a compressive strain of 1% in the extrusion direction (ED), a typical dislocation configuration, including basal I1 stacking faults (SFs) and dislocations, has been established in extension twins. As the strain reaches 7%, the volume fraction of extension twins increases to more than 90% at which point high dense I1 SFs and dislocations occur. After aging for 2 h at 150 °C for the 7% strained sample, masses of basal I1 SFs and dislocations remain in the extension twins and can act as effective nucleation sites and solute fast-diffusion channels for continuous precipitates. Consequently, the precipitates in extension twins become highly dense.

Juvenile hormone esterase (JHE) is a key enzyme for insects, playing an important role in the regulation of insect growth, development, diapause and reproduction. We identified a complete putative JHE of Cydia pomonella (CpJHE-like) which is comprised of a 1 761 bp coding sequence (CDS) encoding 587 amino acid residues from the transcriptome data. The deduced protein sequence of CpJHE-like showed the highest identity of 60.44% with the Adoxophyes honmai JHE (AhJHE) and the minimal identity of 25.81% with Aedes aegypti JHE (AaJHE). CpJHE-like exhibited all the seven typical motifs of the functional JHEs and had the highly consistent tertiary structure with Manduca sexta JHE (MsJHE). Phylogenetic analysis showed that the CpJHE-like was close to two JHEs from the family Tortricidae. The CpJHE-like transcript level take a leap in the 3-day-old fifth instar larva, increased about 300-fold compared to the basal level. Tissue-specific expression profile showed that the CpJHE-like transcript was expressed mainly in the fat body. This study indicates that the CpJHE-like is the functional JHE, which may play vital roles in the development and reproduction of C. pomonella.

Violent attacks have been one of the hot issues in recent years. In the presence of closed-circuit televisions (CCTVs) in smart cities, there is an emerging challenge in apprehending criminals, leading to a need for innovative solutions. In this paper, the propose a model aimed at enhancing real-time emergency response capabilities and swiftly identifying criminals. This initiative aims to foster a safer environment and better manage criminal activity within smart cities. The proposed architecture combines an image-to-image stable diffusion model with violence detection and pose estimation approaches. The diffusion model generates synthetic data while the object detection approach uses YOLO v7 to identify violent objects like baseball bats, knives, and pistols, complemented by MediaPipe for action detection. Further, a long short-term memory (LSTM) network classifies the action attacks involving violent objects. Subsequently, an ensemble consisting of an edge device and the entire proposed model is deployed onto the edge device for real-time data testing using a dash camera. Thus, this study can handle violent attacks and send alerts in emergencies. As a result, our proposed YOLO model achieves a mean average precision (MAP) of 89.5% for violent attack detection, and the LSTM classifier model achieves an accuracy of 88.33% for violent action classification. The results highlight the model’s enhanced capability to accurately detect violent objects, particularly in effectively identifying violence through the implemented artificial intelligence system.

In this study, a nonnegative constrained principal component regression chemical mass balance (NCPCRCMB) model was used to solve the near collinearity problem among source profiles for source apportionment. The NCPCRCMB model added the principle component regression route into the CMB model iteration. The model was tested with the synthetic data sets, which involved contributions from eleven actual sources, with a serious near collinearity problem among them. The actual source profiles were randomly perturbed and then applied to create the synthetic receptor. The resulting synthetic receptor concentrations were also randomly perturbed to simulate measurement errors. The synthetic receptors were separately apportioned by CMB and NCPCRCMB model. The result showed that source contributions estimated by the NCPCRCMB model were much closer to the true values than those estimated by the CMB model. Next, five real ambient data sets from five cities in China were analyzed using the NCPCRCMB model to test the model practicability. Reasonable results were obtained in all cases. It is shown that the NCPCRCMB model has an advantage over the traditional CMB model when dealing with near collinearity problems in source apportionment studies. [ABSTRACT FROM AUTHOR]

In this paper, the microstructure, electromagnetic shielding properties and mechanical properties of Mg-6Zn-3Sn-0.5Cu alloys are studied. As indicated from the results, the phases in the as-cast alloy comprise α-Mg, MgZnCu, Mg2Sn and Mg2Zn3 phases. After homogenization, Mg2Sn and Mg2Zn3 phases are decomposed, but the MgZnCu phase remains. During extrusion, complete dynamic recrystallization (DRX) occurs, and the spherical Mg2Sn phase precipitates dynamically. Due to considerable rod-like β′1 phases precipitate by complying with the [0001] Mg direction, the mechanical properties of aged alloys are remarkably enhanced. The peak-aged alloy achieves the tensile strength of 366 MPa, the yield strength of 358 MPa and the elongation of 7%. With the increase in the size of the β′1 phase, the mechanical properties of the over-aged alloy are reduced. Since the phases precipitate, the electrical conductivity of the alloy is enhanced, and the internal reflective interface increases, so the aged alloys exhibit improved electromagnetic shielding performance. The electromagnetic shielding efficiency of the peak-aged alloy exceeds 105 dB in the range of 30–1500 MHz, showing the best match between mechanical and electromagnetic shielding properties.