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Pure Mg has advantages of low density， good shock absorption performance and good biocompatibility， but its strength is low. Alloying is an important method to modify microstructure and properties of pure Mg. Sn has characteristics of low melting point， high eutectic temperature with Mg， high solid solubility in Mg， stable chemical properties and large output， which is appropriate to be an alloying element. The effects of alloying element Sn on microstructures and properties of Mg alloys were reviewed in this paper. Sn enriches at the front of the solid-liquid interface， dissolves in Mg matrix， reduces the ratio of critical resolved shear stress value of the pyramidal plane to that of the basal plane， and elevates the electric potential of Mg matrix. Mg2Sn precipitates can hinder dislocation and grain boundary movement， and form galvanic corrosion cells with Mg matrix. Therefore， effects of Sn addition include grain refinement， age hardening and strengthening， improving plasticity， accelerating or reducing corrosion rate， enhancing discharge efficiency and discharge potential. At present， the main problems restricting the development of Mg-Sn alloys are slow aging， low hardness and strength. In the future， endeavors should be made to develop rapidly age-hardenable Mg-Sn alloys with high strengths， wrought Sn-containing Mg alloys with good ductility， and Sn-containing structural-functional Mg alloys.

ObjectiveA TaqMan-based real-time fluorescence quantitative polymerase chain reaction （PCR） method was established to detect Clostridium perfringens （C. perfringens） in tap water samples.MethodsThe highly conserved plc gene located in the pseudonucleus of the bacterium was amplified and specific primers and TaqMan probes were designed. After optimization， a TaqMan-based real-time fluorescence quantitative PCR detection method was established. Combined with the filter membrane method， simulated polluted water samples of standard strains containing plc genes were treated， and the established method was tested.ResultsThe established TaqMan-based method for detecting C. perfringens showed high specificity. Ct >40 were found in 13 foodborne pathogens， 3 Clostridium difficile and 1 Clostridium putrefaciens strain. The detection limit of this method was 1×10 copies/μL， showing high sensitivity. The minimum detection limit for the simulated polluted water sample was 1.0×102 CFU/mL. This method was also used to detect 4 simulated water contamination samples and 90 imported water samples. The results showed that C. perfringens could be detected in 2 simulated 1.0×102 CFU/mL-contaminated water samples， while not in 2 simulated 1.0×10 CFU/mL-contaminated and imported water samples.ConclusionThe TaqMan real-time fluorescence quantitative PCR method established in this study for the detection of C. perfringens has good specificity， high sensitivity， and practical value for detecting C. perfringens in water samples.

Introduction: Toxoplasma gondii , an intracellular parasitic protozoan, is globally recognized for its ability to cause parasitic diseases and has developed diverse strategies to evade immune-mediated elimination. The protein ROP16 of T.gondii plays a crucial role in this evasion process by specifically targeting macrophages and mononuclear phagocytes in vivo. However, the precise mechanisms underlying the involvement of type II ROP16 proteins in infection, inflammation, and other processes remain unknown. Methods: To investigate the mechanism of action of gonococcal ROP16 proteins in human macrophages, we constructed a lentivirus overexpressing ROP16 and established stably transfected cell lines. We then analyzed the gene transcriptional profiles of ROP16 II in THP-1 macrophages using transcriptome sequencing. Interaction networks were constructed by screening differentially expressed genes and performing gene function enrichment analysis. Results: As a result, five differentially expressed genes were identified: AAMDC, GPR158, RAD9A, STOML1, and STRA13. Immuno-featured differential analysis showed that type 17 T helper cells were more strongly correlated with GPR158 and STRA13, while CD8 T-cell was most strongly correlated with STOML1. Discussion: Therefore, we conclude that the ROP16 protein plays a pivotal role in THP-1 macrophage infection and these five differentially expressed genes may serve as promising molecular targets for the prevention or control of toxoplasmosis. These findings have significant implications for the diagnosis and treatment of toxoplasmosis. [ABSTRACT FROM AUTHOR]

This study focused on the surface microtextures of quartz grains deposited by dam-break floods in Jiacha Gorge, situated in the middle reaches of the Yarlung Tsangpo River. Utilizing a scanning electron microscope (SEM), 200 quartz grains were observed and analyzed based on their microtextural features. Our findings reveal specific microtextures—such as angular outlines, high relief, flat cleavage surfaces, conchoidal fractures, and steps—that serve as clear indicators of the extreme energy associated with dam-break floods in Jiacha Gorge, distinguishing them from meteorological floods and smaller-scale dam-break events. These features also facilitate the differentiation of dam-break flood deposits from those of other sedimentary environments. This research demonstrates that quartz microtextures are a valuable tool for reconstructing sediment transport processes during extreme flood events. We recommend integrating microtextural analysis with complementary methods to refine interpretations and address methodological uncertainties in future studies. [ABSTRACT FROM AUTHOR]

Grapes are prone to rot and deterioration during storage, seriously affecting their food value. The effects of five extracts, cinnamon, perilla, green tea, pomegranate peel, and ginger, on the microbial growth, weight loss, and sensory quality of grapes were investigated using colony counting and sensory scoring methods. The results showed that perilla and cinnamon extracts had the best effect on maintaining the overall freshness of grapes on the 35th day of storage. The sensory scores were 82 and 80, respectively, and the number of microorganisms was below 6.13 log CFU/g. Further studies revealed that the combination of perilla and cinnamon extracts with Ɛ-polylysine resulted in better inhibition of microbial growth, reduced weight loss, maintained grape quality, and extended storage period to 40 days. An analysis of the active ingredients of the perilla and cinnamon extracts revealed that both extracts contained active antioxidant and antimicrobial ingredients, such as protocatechuic acid, coumaric acid, protocatechuic aldehyde, and rutin. The active ingredients of the perilla extract also included luteolin and apigenin, and those of the cinnamon extract included pinocembrin and epicatechin. These ingredients were deduced to have contributed to preserving the freshness of grapes by the plant extracts. [ABSTRACT FROM AUTHOR]