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In the context of informatization and intelligence, wood identification technology is also developing in the direction of intelligent and efficiency. In order to solve the problems of long working hours, heavy workload, and human interference in traditional wood identification, in this study, the problem of wood species identification was transformed into a multi-classification problem, and a wood species identification model based on convolutional neural network was developed. The classification of wood cross-section images achieved the effect of tree species identification. In this paper, the cross-section images of eight wood species were taken as the research object, and the images were collected to construct and expand the cross-section data set of tree species. Based on the lightweight convolutional neural network algorithm in deep learning and the inverted residual structure, the lightweight tree species detection model was improved for training and testing. The results showed that the MobileNetV3 network model in the convolutional neural network can accurately and efficiently classify wood cross-section images and then identify wood species. Among them, the improved MobileNetV3 model had certain comprehensive advantages, with the classification accuracy improved by 0.43 % when the number of parameters and the amount of calculation were similar. The overall accuracy of wood cross-section image classification can reach 98.24%. [ABSTRACT FROM AUTHOR]

Objective To provide a basis for formulating precise prevention and control strategies, the temporal and spatial aggregation characteristics of county road traffic injury mortality were analyzed, Shandong, 2012-2021. Methods The traffic injury mortality rate was calculated by using the data from the death registration and reporting system of Shandong. Geoda 1.18 and SatScan 9.7 were used for spatial autocorrelation analysis and spatiotemporal scanning analysis to explore the characteristics of spatiotemporal aggregation, and principal component regression analysis was used to explore the influencing factors. Results Road traffic injury mortality rate in Shandong from 2012 to 2021 showed an overall decreasing trend and was high in the fall. The spatial correlation existed in each year, and the "high-high" aggregation area was mainly located in the central and northwestern parts of Shandong. The spatial scan revealed the existence of four clusters across the entire population. Cluster 1 existed from March 2012 to February 2015, covering 26 districts and counties, primarily located in south-central Shandong. Similar to the total population, urban and rural areas were mainly located in the central and southern part of Shandong, and the main urban agglomeration area existed from January 2012 to December 2014, covering 19 districts and counties; The main rural agglomeration area existed from January 2012 to December 2014, covering 38 districts and counties. Principal component regression analysis showed that the variables reflecting the economic and transportation conditions had a greater impact. Among them, the number of permanent residents and the volume of passenger and freight transportation were positively correlated with the mortality rate, while others were negatively correlated. Conclusion From 2012 to 2021, the mortality rate of road traffic injuries in Shandong showed a decreasing trend. The main agglomeration area exists in the central and southern part of Shandong, and the rural agglomeration is more obvious. According to the characteristics of clustering, attention should be paid to the enforcement of laws and regulations, infrastructure construction, population flow and other factors in high-risk areas, and prevention and control strategies should be adopted or adjusted according to local conditions. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effect of salt-reducing intervention on the content of sodium of dishes in catering units in Shandong. Methods A stratified, random sampling method was used to recruit a representative sample of catering units, and finally 60 catering units were selected and divided into the intervention group and control group. The content of sodium was determined according to the national detection standard (GB/T 5009.91-2003). Results After six months of intervention, the content of sodium of dishes in the intervention group's catering units decreased from 436 mg/100 g 369 mg/100 g (Z = -3.88, P <0.001), with a decrease of 15.4%, while the control group only decreased by 4.3%. The monthly average salt consumption per meal in the intervention group decreased from 6.49 to 6.03 grams (Z = -3.12, P <0.05). Conclusion The salt-reducing intervention can reduce the content of salt of the dishes, and the monitoring of indicators, such as salt consumption, number of diners and sales ratio of low salt dishes in catering units, should be complied. [ABSTRACT FROM AUTHOR]

Abstract: l‐Phenylalanine is an important amino acid that is widely used in the production of food flavors and pharmaceuticals. Generally, l‐phenylalanine production by engineered Escherichia coli requires a high rate of oxygen supply. However, the coexpression of Vitreoscilla hemoglobin gene (vgb), driven bya tac promoter, with the genes encoding 3‐deoxy‐ d‐arabinoheptulosonate‐7‐phosphate synthetase (aroF) and feedback‐resistant chorismate mutase/prephenate dehydratase (pheAfbr), led to increased productivity and decreased demand for aeration by E. coli CICC10245. Shake‐flask studies showed that vgb‐expressing strains displayed higher rates of oxygen uptake, and l‐phenylalanine production under standard aeration conditions was increased. In the aerobic fermentation process, cell growth, l‐phenylalanine production, and glucose consumption by the recombinant E. coli strain PAPV, which harbored aroF, pheAfbr, and tac‐vgb genes, were increased compared to that in the strain harboring only aroF and pheAfbr (E. coli strain PAP), especially under oxygen‐limited conditions. The vgb‐expressing strain PAPV produced 21.9% more biomass and 16.6% more l‐phenylalanine, while consuming only approximately 5% more glucose after 48 H of fermentation. This study demonstrates a method to enhance the l‐phenylalanine production by E. coli using less intensive and thus more economical aeration conditions. [ABSTRACT FROM AUTHOR]

Abstract: Ultrasonic‐microwave synergistic extraction (UMSE) was used to extract from Morchella conica polysaccharide (MCP). The effect of three independent variables (microwave power, ratio of water volume to raw material weight (W/M ratio), extraction time) on extraction yield was optimized using response surface methodology with a Box–Behnken design. The high R2 values (>.966) demonstrated the response and independent variables predicted by polynomial model were fitted. The optimal conditions for MCP extraction were microwave power of 210.61 W, W/M ratio of 41.07:1, and extraction time of 126.98 s. Under these conditions, the experimental yield was 7.53 ± 0.17%. By comparison of ultrasound assistant extraction (UAE) and microwave assistant extraction (MAE), the extraction efficiency of UMSE is the highest. Practical applications: Morchella conica is a species of mushroom contained with amount of bioactive polysaccharide. Novel extraction technique UMSE was applied to extract MCP because the high synergistic energy promotes cell disruption and MCP release. Compared with the traditional extraction technology, UMSE requires shorter time and higher efficiency. These effects make UMSE economic to gain bioactive MCP. Thus, the application of UMSE can be useful for improvement on industrial extraction processes of food and natural products. [ABSTRACT FROM AUTHOR]