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Due to the low level of industrialization of traditional fermented food in china, people rely a lot on experience and knowledge in the production process, resulting in unstable product quality and ...

The current work numerically investigates commercial polycrystalline Ag/17vol.%SnO2 composite tensile deformation behavior with available experimental data. Such composites are useful for electric contacts and have a highly textured initial material status after hot extrusion. Experimentally, the initial sharp fiber texture and the number of Sigma3-twins were reduced due to tensile loading. The local inhomogeneous distribution of hardness and Young’s modulus gradually decreased from nanoindentation tests, approaching global homogeneity. Many-scale simulations, including micro-macro simultaneous finite element (FE) and discrete dislocation dynamics (DDD) simulations, were performed. Deformation mechanisms on the microscale are fundamental since they link those on the macro- and nanoscale. This work emphasizes micromechanical deformation behavior. Such FE calculations applied with crystal plasticity can predict local feature evolutions in detail, such as texture, morphology, and stress flow in individual grains. To avoid the negative influence of boundary conditions (BCs) on the result accuracy, BCs are given on the macrostructure, i.e., the microstructure is free of BCs. The particular type of 3D simulation, axisymmetry, is preferred, in which a 2D real microstructural cutout with 513 Ag grains is applied. From FE results, Sigma3-twins strongly rotated to the loading direction (twins disappear), which, possibly, caused other grains to rotate away from the loading direction. The DDD simulation treats the dislocations as discrete lines and can predict the resolved shear stress (RSS) inside one grain with dependence on various features as dislocation density and lattice orientation. The RSS can act as the link between the FE and DDD predictions.

The diverse bacteria encoding histidine decarboxylase gene during the fermentation of Sichuan-style sausages were investigated by culture-dependent techniques, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and high-throughput sequencing. All microbial indicators exhibited the advantages of mixed starter culture and the stability of microecosystem was more in the inoculation group than in the control group. DGGE and selected band sequencing were used to investigate the bacterial diversity of these sausages. Weissella were the main lactic acid bacteria (LAB) in the initial fermentation stage, whereas Weissella and Lactobacillus were the dominant bacteria in the later fermentation stage. After sequence alignment analysis, Enterobacter aerogenes and Citrobacter freundi were the two main bacteria encoding histidine decarboxylase gene and could produce histamine. These findings facilitate the better understanding of bacteria producing histidine decarboxylase during sausage fermentation and provide a theoretical basis for the control of histamine-producing bacteria in the process of fermented sausage processing.

Additional file 3: Supplementary Figure 3. Labelled retinal layers (ILM, internal limiting membrane. NFL, nerve fiber layer. GCL, ganglion cells layer. IPL, inner plexiform layer. INL, inner nuclear layer. OPL, outer plexiform layer. ONL, outer nuclear layer. ELM, external limiting membrane. IS/OS, inner segment/outer segment). Adrenergic and cholinergic signaling-related gene set.

Additional file 2: Supplementary Figure 2. Flow chart of experimental design.