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Nitrile butadiene rubber （NBR） is a crucial sealing material for oil-immersed equipment， and its properties have a direct impact on the safe operation of equipment. With elastic strain energy density and hardness as the property parameters， the infrared spectra and tensile fracture characteristics are used to analyze the structural changes in NBR immersed in oil to determine the relationship between its mass-transfer behaviors and the property variations and elucidate the mechanism of property degradation. The findings reveal that NBR experiences swelling when immersed in oil， resulting in a significant reduction in both elastic strain energy density and hardness. These two indices exhibit a strong correlation with oil immersion parameters. Mass transfer behaviors， such as oxidization of functional groups， oil infiltration， and additive dissolution， emerge as the primary drivers behind the property change.

Objective: To solve the problems of an uncertain fermentation process, a long fermentation period, and the unstable quality of traditional naturally fermented preserved fish. Methods: The lactic acid bacteria were isolated from low-salt preserved red fish, and the inhibition ability, salt tolerance, and acid production ability of the strains were investigated. The lactic acid bacteria suitable for fermentation were screened out, and the fermentation of preserved red fish was intensified by inoculation. The amount of red rice flour added, the amount of salt added during curing, and the fermentation temperature were optimized in the fermentation process. Results: There were 22 strains of Pediococcus with inhibitory effect on Escherichia coli or Staphylococcus aureus were isolated, among which Pediococcus pentosaceus P-56 had the best inhibitory effect on Escherichia coli and higher tolerance to bile salt and acid; After inoculation fermentation and process optimization. The pH value of the Zhayu decreased to 4.42 at 4 days of fermentation, the TCA-soluble peptide content was 434.99 μmol/g and the sensory score reached 45.7. Conclusion: The optimal process conditions for the fermentation of preserved red fish with lactic acid bacteria were: 4% salt addition for curing, 4% red yeast rice flour addition and fermentation temperature of 32 ℃.

Objective To investigate the classification of atrophic glossitis and to study the correlation between the classification and changes of VitB12, folic acid (FOL) and blood cell parameters.Methods A total of 70 patients with atrophic glossitis (AG) were divided into complex type and simple type according to whether they had ulcer or erosion on the tongue mucosa or not. Another 65 healthy subjects during the same period were collected as the control group. The levels of vitamin B12, FOL and blood cell parameters were statistically analyzed using SPSS 25.0 software package.Results The levels of vitamin B12, red blood cell count (RBC) (3.52 ± 0.69) × 1012·L-1, hemoglobin (HGB)(11.97 ± 1.70) g·dL-1, white blood cell count (WBC) (4.85 ± 1.16) × 109·L-1, neutrophil count (NEUT) (2.76 ± 0.99) × 109·L-1, lymphocyte count (LYMPH) (1.48 ± 0.44) × 109·L-1 in complex type AG group were lower than those in simple type AG group (P0.05). The levels of VitB12, MCV, MCH, MCHC, WBC, lymph and neut were correlated with the classification of atrophic glossitis (P < 0.05). Conclusion VitB12 deficiency was more apparent in complex AG, especially in large cell anemia, which correlated with the levels of WBC, NEUT, and LYMPH.

ObjectiveThe prediction of gestational diabetes mellitus (GDM) by body composition-related indicators in the first trimester was analyzed under different body mass index (BMI) values before pregnancy.MethodsThis was a retrospective analysis of pregnant women who were treated, had documented data, and received regular perinatal care at the Third Affiliated Hospital of Zhengzhou University from January 1, 2021, to December 31, 2021. Women with singleton pregnancies who did not have diabetes before pregnancy were included. In the first trimester (before the 14th week of pregnancy), bioelectric impedance assessment (BIA) was used to analyze body composition-related indicators such as protein levels, mineral levels, fat volume, and the waist-hip fat ratio. The Pearman’s correlation coefficient was used to evaluate the linear relationship between the continuous variables and pre-pregnancy body mass index (BMI). In the univariate body composition analysis, the association with the risk of developing GDM was included in a multivariate analysis using the relative risk and 95% confidence interval obtained from logarithmic binomial regression, and generalized linear regression was used for multivariate regression analysis. Furthermore, the area under the curve (AUC) was calculated by receiver operating characteristic (ROC) curves. The optimal cutoff value of each risk factor was calculated according to the Youden Index.ResultsIn a retrospective study consisting of 6698 pregnant women, we collected 1109 cases of gestational diabetes. Total body water (TBW), protein levels, mineral levels, bone mineral content (BMC), body fat mass (BFM), soft lean mass (SLM), fat-free mass (FMM), skeletal muscle mass (SMM), percent body fat (PBF), the waist-hip ratio (WHR), the visceral fat level (VFL), and the basal metabolic rate (BMR) were significantly higher in the GDM group than in the normal group (P

Interunit dispersion problems have been studied previously mainly through on-site measurements, wind tunnel tests, and CFD simulations. In this study, a scaled outdoor experiment was conducted to examine the interunit dispersion characteristics in consecutive two-dimensional street canyons. Tracer gas (CO2) was continuously released to simulate the pollutant dispersion routes between the rooms in street canyons. The reentry ratio was analyzed to reveal the interunit dispersion of the rooms in the street canyons. This study provides authentic airflow and pollutant dispersion information in the street canyons in an urban environment.

This paper evaluates the ecological health of Shiyang River Basin by the adaptive wind-driven optimization (AWDO) algorithm and support vector regression (SVR) coupled algorithm for problems in health assessment of watershed ecosystem,finds the optimal parameters of support vector machine (SVM) by AWDO algorithm for uncertainty of parameters from SVM,proposes an evaluation model based on AWDO-SVR algorithm,and evaluates nine indexes such as water resource endowment,water resource development and utilization,and social and economic function of Shiyang River Basin by the model with advantages of fast and simple operation and no need of weight.The results show that the ecological health is sub-health for the upper reaches of Shiyang River,and morbid for the middle and lower reaches respectively.The evaluation result is the same as that of the variable set model,indicating that AWDO-SVR algorithm can be effectively applied to the ecosystem health evaluation of the river basin.