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ObjectiveThe aim of this study was to evaluate the serotype， drug resistance， and molecular typing characteristics of Salmonella isolated from patients with foodborne diseases in Guizhou Province in 2021.MethodsA total of 164 Salmonella strains were isolated from patients with diarrhea under the Guizhou Provincial Active Surveillance of Foodborne Diseases program in 2021. These strains were subjected to slide agglutination serotyping test， minimum inhibitory concentration tests with 14 antibiotics， and pulsed-field gel electrophoresis （PFGE） for molecular typing.ResultsThe 164 Salmonella strains were divided into 25 serotypes. The dominant serotypes were S. typhimurium （46.34%，76/164）， S. enteritidis （15.24%，25/164）， and S. javana （9.15%，15/164）. The drug resistance rate of the 164 Salmonella strains was 100% （164/164）. The multidrug resistance rate was 86.59% （142/164）. Out of the 15 antibiotics tested， resistance was most frequently observed against ampicillin （95.12%，156/164）， tetracycline （78.05%，128/164）， and nalidixic acid （63.41%，104/164）. Seventy-two S. typhimurium， 24 S. enteritidis， and 15 S. javana strains were divided into 58， 12， and 3 different PFGE clusters， respectively.ConclusionThere were many Salmonella serotypes detected in patients with diarrhea in the Guizhou Province， and multidrug resistance was common. PFGE fingerprints demonstrated genetic diversity of the isolated strains. Monitoring of drug resistance in Salmonella should be strengthened， especially for the clinical treatment of S. typhimurium.

Objective: Phytochemistry, microbiology, flavor and functional properties of fermented papaya juice were examined in relation to Lactobacillus plantarum (Lp), Lactobacillus rhamnosus (Lr), Lactobacillus acidophilus (La) and their mixed strains (Lp+Lr、Lp+La、Lr+La), in order to develop a probiotic papaya beverage with improved functionality and health-promoting properties. Methods: In thisstudy, changes in pH, total soluble solids, titratable acid, viable cells, glucose, fructose, sucrose, organic acids and volatile compounds were determined. The contents of total phenolics and total flavonoids, as well as the inhibitory activity against α-glucosidase and tyrosinase enzymes during the fermentation process, were also investigated. Results: The single-and mixed strain cultures showed similar changes during the 72 h fermentation period, exhibiting significantly decreased pH and increased acidity. The contents of lactic acid and succinic acid greatly increased, whereas that of citric acid and malic acid decreased significantly. After fermentation, the content of total phenolics and flavonoids increased in papaya juice. Pearson's correlation analysis revealed that the metabolism of phenolics likely contributed to enhancing the inhibitory activity against α-glucosidase and tyrosinase enzymes. Among all fermentation groups, the papaya juice fermented by Lp exhibited the highest contents of lactic acid, total phenolics, and flavonoids, showing the strongest inhibitory effect against α-glucosidase and tyrosinase enzyme. Additionally, six types of aromatic compounds were primarily detected in unfermented papaya juice, with butyric acid content being the highest (89.742%), followed by linalool. After fermentation, a total of 25 aromatic compounds were identified in the six fermented juice samples, and the content of butyric acid declined significantly, which reduced the unpleasant odor of papaya. In all fermentation groups, the Lp single-strain culture generated the most volatile components (18 types), while the Lp+Lr mixed culture achieved the lowest (5 types). Although the Lp+Lr mixed-strain culture had the highest number of viable bacteria [7.61 lg (CFU/mL)], the Lp single-strain culture may be preferable overall. Conclusion: The Lp single culture could improve the sensory characteristics of papaya juice and enhance its beneficial properties.

Although significant progress has been made in the self-assembly of nanostructures, present successes heavily rely on precision in building block design, composition, and pair interactions. These requirements fundamentally limit our ability to synthesize macroscopic materials where the likelihood of impurity inclusion escalates and, more importantly, to access molecular-to-nanoscopic-to-microscopic-to-macroscopic hierarchies, since the types and compositions of building blocks vary at each stage. Inspired by biological blends and high-entropy alloys, we hypothesize that diversifying the blend's composition can overcome these limitations. Increasing the number of components increases mixing entropy, leading to the dispersion of different components and, as a result, enhances interphase miscibility, weakens the dependence on specific pair interactions, and enables long-range cooperativity. This hypothesis is validated in complex blends containing small molecules, block copolymer-based supramolecules, and nanoparticles/colloidal particles. Hierarchically structured composites can be obtained with formulation flexibility in the filler selection and blend composition. It is worth noting that, by adding small molecules, we can solve the size constraint that plagues traditional block copolymer/nanoparticle blends. Detailed characterization and simulation further confirm that each component is distributed to locally mediate unfavorable interactions, cooperatively mitigate composition fluctuations, and retain structural fidelity. Furthermore, the blends have sufficient mobility to access tunable microstructures without compromising the order of the nanostructure. Besides establishing a kinetically viable pathway to release current constraints in the composite design and to navigate uncertainties during structure formation over multiple length scales, the present study demonstrates that entropy-driven behaviors can be realized in systems beyond high-entropy alloys despite inherent differences between metal alloys and organic/inorganic hybrids.

The polymer chain architecture is an important factor determining the phase behavior of nanoparticle (NP) assembly in polymer matrices. Block copolymers (BCPs) containing a random copolymer (RCP) block present a convenient variation on traditional BCPs to tune the interaction parameters between the polymer blocks and the nanofillers as well as to evaluate the effect of the chain architecture on the NP arrangements within BCP microdomains. Here, we synthesized BCPs with a coil polystyrene (PS) block and a comb RCP block through reversible addition-fragmentation chain transfer polymerization. The RCP block consists of methyl- and lauryl acrylates, the latter of which confers a long-chain alkyl moiety to favorably interact with alkyl-passivated NPs. BCPs showing lamellar, cylindrical, and mixed morphologies were obtained by varying the volume fractions of the RCP block (fRCP). In comparison to coil-coil BCP, the coil-comb BCPs show highly asymmetric phase behavior with respect to fRCP, where lamellar morphologies were observed at fRCP from 0.31 to 0.51. NPs in the size of 4-5 nm were successfully incorporated in the RCP block of the BCPs with periodicities of 30-60 nm. An order-to-order phase transition from lamellae to PS cylinders was observed after the addition of only 1-2 vol % 5 nm NPs into the BCP with a periodicity of 25 nm and fRCP of 0.51. Self-consistent field theory-density functional theory simulations qualitatively described the observed morphologies and phase transitions in the nanocomposites. The current study presents a platform to fabricate nanocomposites with NP assemblies in coil-comb BCPs that contain a random copolymer block and provides insight into how polymer chain architectures can affect the phase behavior of BCPs and nanocomposites.