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Aluminum alloy possesses poor plastic deformation ability under quasi-static stamping (QS). Hence, the plastic deformation behavior and microstructure evolution of 5052 aluminum alloy in electromagnetic driven stamping (EMDS) and QS under different heat treatment conditions were investigated in this paper. Compared with QS, EMDS can respectively improve the strength and plasticity of 5052-O aluminum alloy by 0.9% and 12%, as well as 4.6% and 30% in 5052-H32 state. The enhancement effect of EMDS on 5052-H32 aluminum alloy is more obvious. This is due to the 5052-H32 aluminum alloy has more initial dislocations, which will promotes multi-system slip and cross-slip of dislocation at high strain rates. Microscopic analysis indicates that the 5052-H32 aluminum alloy in EMDS possessed a more uniform dislocation distribution and a higher grain refinement degree. For a higher forming height, the grain boundary, dislocation and texture exhibit more obvious effects on the strength of the materials. It provides a theoretical basis for the forming mechanism of 5052 aluminum alloy during EMDS under different heat treatment conditions.

The 2024 aluminum alloys are used in a wide range of industrial applications, and improvement in their formability and serviceability is key in the manufacturing process. Electromagnetic forming (EMF) has proven to be an effective means of improving the formability of aluminum alloys. By combining EMF and heat treatment process, three samples of 2024 aluminum alloy were designed: Sample A (annealing + EMF + solid-solution + aging), Sample B (solid solution + EMF + aging), and Sample C (solid solution + pre-aging + EMF + aging). The effects of three heat treatment regimens on the properties and microstructure of 2024 aluminum alloy were studied by hardness test, intercrystalline corrosion, and exfoliation corrosion, as well as by microscopic characterization techniques including scanning electron microscopy and transmission electron microscopy. The results show that the dislocations-induced deformation could shorten the time to peak aging and led to the increase in peak strength. Sample C exhibited the highest strength and sample A exhibited the highest elongation and corrosion resistance. The microscopic results show that the differences in properties were mainly influenced by the distribution of precipitated phases and the width of the precipitation-free zone. The discrete and coarse grain boundary precipitations make sample A have excellent corrosion resistance. The fine and dense precipitated phases provide good strength for samples B and C, but also reduces the elongation. This research has important implications for rational formulation based on the combination of EMF and heat treatment processes for the fabrication of Al–Cu–Mg alloys. Conclusions: may be made more concise. They should focus on the mechanisms responsible for high strength or corrosion resistance rather than the values obtained that are shown in results.

It has been reported that the forming limit of materials can be improved during electromagnetic forming (EMF). However, the detailed mechanism of this phenomenon remains unclear. The effect of initial state on the EMF process of AA1060 is systematically investigated. AA1060-O and AA1060-H24 alloys are subjected to quasi-static (Q-S) stamping and EMF, respectively. Compared to the Q-S stamping, the forming limit and hardness of AA1060-H24 sheet are increased by 68.3% and 9.4% under EMF. However, the forming limit of AA1060-O sheet is not improved. It is found that both groups of aluminum alloys exhibit high dislocation density after Q-S stamping and the dislocation movement occurs via the plane slip mode. Moreover, dislocation cells and wavy slips are observed in AA1060-H24 sample after EMF. In the case of AA1060-O sample, the intragranular dislocation density is low without wavy slip. Therefore, the wavy slip mode may be the reason for improved forming limit under the influence of EMF. In addition, the textural strength of EMF sample is different from the Q-S deformation sample and EMF sample exhibits a higher Taylor factor value. The changes in grain size, dislocation density and texture strength alter the overall strength. The current study provides the theoretical basis for the mechanism of improved forming limit under the action of EMF.

Vibrio vulnificus is a facultative anaerobic, alkalophilic, halophilic, mesophilic, Gram-negative bacterium that can cause severe wound infection, sepsis and diarrhea. This paper reported a case of 85-year-old male patient infected with Vibrio vulnificus due to being stabbed by a sea shrimp. This patient also had diabetes with a long history of alcoholism. Due to bacterial pathogenicity and the patient's underlying diseases, his condition deteriorated rapidly. Based on the rapid diagnosis of Vibrio vulnificus using the next-generation sequencing（NGS）technology and blood culture method, as well as the selection of the most effective antibiotics via drug sensitivity test, this patient underwent precise antimicrobial treatment, thorough debridement and drainage within the shortest possible time, and thus the prognosis of this patient was greatly improved. In this paper, we have systematically explored the epidemiology, clinical features, diagnosis and treatment of Vibrio vulnificus infection, thus providing a practical reference for the clinicians to quickly identify and treat possible Vibrio vulnificus infection in diabetic patients after contacting with sea water or seafood.

Silver nanoparticles (AgNPs) have raised public concern due to their widespread application in the field of agriculture, medicine, and environment and their potential toxic effects on humans and the environments. In this study, biosynthesis of nanosilver particles mediated by Trichoderma longibranchiatum using orthogonal experimental design (OED) was optimized. Silkworm larvae were exposed via the mulberry leaves to AgNPs to evaluate their toxic effects. The results showed that 2 mmol/L silver nitrate and 55 °C of reaction temperature at pH 7.0 for 24 h were the optimum values for AgNPs biosynthesis with the synthesis amount and antifungal activity of AgNPs as the indices. The characterization of the biosynthesized AgNPs was conducted using electron microscopy, energy dispersive X-ray analysis (EDS), UV/visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The crystalline structured nanoparticles were spherical or polyhedral with a mean size ranging about 5–50 nm. FTIR showed that many functional group moieties (–OH, –CH3, –C–O, etc.) involved as a capping and reducing agent in AgNPs biosynthesis. After the larvae were fed with 50 mg/mL AgNPs, there were no obvious adverse effects on the growth of larvae and cocoon quality. Further supplement of AgNPs-B could promote the weight of larvae and the cocoon shell ratio. The data presented herein provided valuable information on a reliable eco-friendly, simple, low-cost biosynthesis of AgNPs and its biosafety evaluation which may contribute to its increased application in the future.

Reading is an important skill for human beings to obtain information, whose acquisition is a major learning task for children. Especially, compared with single word reading, text reading requires an integration of multiple cognitive processes, which makes its underlying neural developmental mechanism not only extremely complicated but also remained poorly understood. Employing the graph theory analysis method, the present study explored the development of brain in the context of story reading from the perspective of connectomics. Forty-two primary school students and thirty-two adults read the stories in the functional magnetic resonance imaging (fMRI) experiment. We found that compared with children, adults had increased connectivity strength, nodal degree, and modular interactions for vision-related and semantics-related brain regions while decreased connectivity strength, nodal degree, and modular interactions for phonology-related brain regions. Brain-behavior association analysis suggested that the transmission to vision-related brain circuits would enhance the reading performance in adults, whereas phonology-related brain circuits played important roles in children’s reading before they develop into fluent readers. Collectivity, we highlight a shift from reliance on phonology-related networks to semantics-related and vision-related networks with age for text reading, which provides insights into the underlying neural signature of developmental cognitive mechanisms.