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Aiming at the stress distribution and roadway layout problems under the narrow coal pillars in close distance coal seam group, theoretical analysis, numerical simulation and field measurement are used to analyze the stress distribution characteristics of the coal strata under the narrow coal pillars. Studies have shown that, affected by the sequential mining of adjacent working faces, the overlying rock layer of the coal pillar revolves toward the back of the working face, which causes the peak support stress to shift to the side of the back mining face, and the supporting stress of the coal pillars is distributed asymmetrically; affected by the supporting stress, the stress distribution of the coal strata under the coal pillar shows asymmetry corresponding to the supporting stress, and the degree of asymmetry increases with the decrease of the coal pillar width. Combined with actual engineering cases, according to the distribution of the vertical stress and principal stress difference of the lower coal seam floor, and taking into account the influence of the asymmetric distribution of stress, the location of the mining roadway in the lower coal seam is finally determined.

High quality project discovery is an important prerequisite and guarantee for technological innovation. Analyzing the influencing factors of major key technology project discovery in aviation field can effectively support its project discovery process. On the basis of summarizing the general process of knowledge aggregation and analyzing the characteristics of major key technology project discovery in aviation field,a model of major key technology project discovery in aviation field based on knowledge aggregation process is constructed. On this basis,through interview analysis and questionnaire survey,the influencing factors of major key technology projects in aviation field are explored,and classified by factor analysis in this paper. The results show that the discovery of major key technology projects in the aviation field is affected by a total of 10 factors in 3 categories,including personnel material support,project discovery technology and project discovery process management.

Recent studies show that the shape of the internal cavity with periodic distribution has a significant impact on the characteristics of the anechoic coating. In this study, we proposed a genetic algorithm-based method for optimizing the design parameters of anechoic coating. By transforming the 3D finite element model (FEM) of the anechoic coating to a 2D axisymmetric finite element model (AFEM), and COMSOL with MATLAB co-simulation combined with the genetic algorithm applied to obtain the optimal parameters. Lots of simulation results demonstrate that as the number of generated segments on the rotating surface in the internal cavity increases, the sound absorption performance of the anechoic coating greatly improves. The expected optimization effect is achieved by substituting the optimized parameters into 3D FEM. Moreover, the reflection coefficient of an anechoic coating gradually increases with the increasing of incident angles. In the middle-high frequency range, when synthetical optimizing the material properties and cavity shape, better sound absorption performance can be obtained in comparison to the case where only the cavity shape is optimized.

ObjectivesWith the deepening of non-drug intervention research on human mental health, more and more attention has been paid to the benefits of horticultural activities and green exercise on physical and psychological health. This study compared the affect improvement between horticultural activities with the same intensity and green exercise and that with or without green plants to verify the value of horticultural activities and green exercise in improving human affect and the importance of green plants.MethodsA total of 160 subjects aged 18–26 years (average age 22.5 years) were recruited and randomly divided into a control group, a horticultural activity group with green plants, a horticultural activity group without green plants, and a green exercise group. Demographics, sociological variables, and daily physical activity levels were investigated. Green space at Zhejiang Normal University was selected as the test site. After finishing the preparation work, the subjects sat quietly for 8 min before the pre-test. The horticultural group completed 20 min of horticultural activities {8 min of digging [40%*HRR(heart rate reserve) + RHR(resting heart rate)] + 8 min of transplantation [(50%*HRR + RHR) + 4 min of watering (30%*HRR + RHR)]}. The group returned to a calm state (no less than 20 min) for the post-test. The green exercise group completed a 20-min power bike ride. The activity intensity and activity time of the green exercise group were determined according to the activity intensity and time of the horticultural group. Dependent variables were collected, including blood pressure, positive/negative affects, heart rate variability (RMSSD, SDNN, and LF/HF), and controlled covariate environmental parameters (field temperature, humidity, and noise).Results(1) A significant difference was observed in the improvement effect except for negative affect between the green horticultural activity group and the green exercise group (F = 3.310; ɳp2 = 0.046; p = 0.037). No significant difference was observed in other affect indicators. (2) In the same pattern of with and without green plant horticultural activity group, the green plant horticultural activity group had a better effect on the improvement of affect, and the two groups had a better negative affect (F = 3.310; ɳp2 = 0.046; p = 0.037), SDNN index of heart rate variability(F = 1.035; ɳp2 = 0.015; p = 0.039), and RMSSD index (F = 2.225; ɳp2 = 0.032; p = 0.014), and no significant difference was observed in the improvement effect of other affect indicators between the two groups.ConclusionsHaving green horticulture can give the same intensity as green exercise and affect improvement. Findings suggest that people can choose green exercise or horticultural activities according to their preferences and physical characteristics in the two physical activities. Under the same pattern of horticultural activities, green plants are the key factor in improving the affect of horticultural activities. Choosing suitable plant types in horticultural activities is positively significant in enhancing affect.

Inositol hexaphosphate (IP6) is a phytochemical widely found in grains and legumes that plays an anti-cancer role. However, the mechanism underlying the inhibition of colorectal cancer metastasis by IP6 through host genes, gut microbiota, and their interactions remain elusive. In this study, 16S rRNA sequencing was used to study the effect of IP6 on gut microbiota in an orthotopic transplantation model of colorectal cancer mice. The transcriptome was used to study the changes of host genes in metastasis and the relationship with gut microbiota. The results showed that the gut microbiota composition of model mice was significantly different from that of normal mice. The beta diversity partly tended to return to the normal level after IP6 intervention. Especially, Lactobacillus helveticus and Lactococcus lactis were recovered after IP6-treated. Enrichment analysis showed that the enrichment score of the Cytokine-Cytokine receptor interaction signal pathway decreased after IP6 treatment compared to the model group. Further analysis of differentially expressed genes (DEGs) in this pathway showed that IP6 reduced the expression of the Tnfrsf1b gene related to the area of liver metastasis, and the Tnfrsf1b gene was negatively correlated with the relative abundance of Lactobacillus helveticus. Our results presented that host gene, microbiome and their interaction may serve as promising targets for the mechanism of IP6 intervention in colorectal cancer metastasis.

The research on the highly efficient reutilization of mixed recycled aggregates (MRA) produced from construction and demolition waste has attracted significant attention globally. In this study, the feasibility of using 100% MRA in cement-stabilized materials was investigated. The mechanical properties and microstructures of cement-stabilized MRA (CSMRA) materials containing 100% MRA were systematically examined through unconfined compressive strength (UCS) test, indirect tensile strength (ITS) test, drying shrinkage test, X-ray diffraction analysis, mercury intrusion porosimetry, and scanning electron microscopy. Results showed that the UCS and ITS of CSMRA materials were significantly enhanced with the increase of cement content and curing age, and there was almost a linear relationship between the UCS and ITS. The failure behavior of CSMRA materials under load showed three typical stages: compaction stage, elastic stage, and yield stage. The increase of the cement content caused the drying shrinkage deformation of CSMRA to increase sharply when the cement content exceeded 4%. The microstructural analysis indicated that cement had both filling and binding effects on CSMRA materials. The strength growth with cement content and curing age was because of the constant hydration of cement minerals, producing more calcium silicate hydrate binders between aggregates. Moreover, the increasing cement content could reduce the porosity and optimize the pore structure distribution of CSMRA materials. The findings of this study demonstrate that the use of 100% MRA in cement-stabilized materials as a road base is feasible, which will significantly enhance the utilization efficiency of MRA.

Abstract. Background:. Disease activity indices (DAIs) including disease activity score 28 (DAS28), simplified disease activity index (SDAI), and clinical disease activity index (CDAI) have been widely used in clinical practice and research studies of rheumatoid arthritis (RA). The objective of our study was to evaluate the correlation and concordance among different DAIs in Chinese patients with RA. Methods:. A cross-sectional study, including patients enrolled in the Chinese registry of rheumatoid arthritis from November 2016 to August 2018, was conducted. The correlations were evaluated using Spearman correlation coefficient and concordance with Bland-Altman plots, quadratic weighted kappa, and discordance rates in the crosstab. For other indices, the optimal cutoff points corresponding to SDAI remission were explored through receiver operating characteristic curve analysis. Results:. A total of 30,501 patients were included, of whom 80.46% were women. Most individuals were with moderate disease activity or high disease activity. High correlations among DAS28-erythrocyte sedimentation rate (ESR) and DAS28-C-reactive protein (CRP), SDAI and CDAI were observed. Similarly, the weighted kappa value among the indices was high. In Bland-Altman plots, a positive difference between DAS28-ESR and DAS28-CRP was observed, with an absolute difference of >1.2 in 3079 (10.09%) patients. In crosstab, approximately 30% of the patients were classified into different groups. Concordance values between SDAI remission and the optimal cutoff points of DAS28-ESR, DAS28-CRP, and CDAI were 3.06, 2.37, and 3.20, respectively. Conclusions:. Although DAIs had high correlations and weighted kappa values, the discordance between DAIs was significant in Chinese patients with RA. The four DAIs are not interchangeable.

ObjectivesTo analyze the clinical characteristics, echocardiographic features, and prognosis of fetuses based on three groups of cardiac manifestations associated with maternal anti-Ro and anti-La antibodies in China. This study included three groups: the isolated-arrhythmia, isolated-endocardial fibroelastosis (EFE), and mixed groups.MethodsWe prospectively evaluated 36 fetuses with cardiac manifestations due to maternal anti-Ro and anti-La antibodies from our center between 2016 and 2020 in China. Clinical and echocardiographic data were collected.ResultsThere were 13 patients (36%) in the isolated-arrhythmia group, eight (22%) in the isolated-EFE group, and 15 (42%) in the mixed group. All patients in the isolated-EFE group presented with mild EFE. Severe EFE was identified in four patients (27%) in the mixed group. Atrioventricular block (AVB) was more common in the isolated-arrhythmia group (13, 100%) than in the mixed group (6, 40%; p = 0.001). Moderate-severe mitral regurgitation (p = 0.006), dilated cardiomyopathy (DCM, p = 0.017), and low cardiovascular profile scores (p = 0.013) were more common in the mixed group than in the other two groups. Twenty-one mothers decided to terminate the pregnancy and 15 fetuses were born with regular perinatal treatment. They all survived at 1 year of age. One patient in the isolated-arrhythmia group and two in the mixed group required a pacemaker due to third-degree AVB or atrioventricular junctional rhythm. Five patients in the isolated-EFE group and five in the mixed group had no DCM or heart failure and the location of mild EFE was significantly reduced.ConclusionFetal cardiac manifestations due to maternal anti-Ro and anti-La antibodies can be divided into three groups, i.e., the isolated-arrhythmia, isolated-EFE, and mixed groups. AVB usually occurs in the isolated-arrhythmia group. Severe EFE, moderate-severe mitral regurgitation, and DCM mainly appear in the mixed group. Location of mild EFE significantly reduces after birth and the outcome of fetuses with mild EFE depends on the presence of arrhythmia and its subtypes.

The 2018 Global Innovation Index ranks Pakistan 118 out of 126 in innovation. One of the main reasons why developing countries, such as Pakistan, fail to innovate is their improvisation of astute and concurrent knowledge. This study explores the contemporary hurdles that lead to manufacturing firms' low agility and innovation performance. Based on the theory of dynamic capability view and the theory of absorptive capacity, we propose that the knowledge absorption capacity of firms can help them organize or utilize dynamic capabilities, such as big data analytics and digital platform capability, to enhance their agility and innovation performance. However, in the presence of a diversified organizational culture (i.e., flexibility orientations and data-driven culture), the desired outcomes may be affected. For this purpose, this study performed a questionnaire survey to collect data for validating the theoretical model. The collected responses from 325 manufacturing firms were analyzed using structural equation modeling, and empirical results reveal a positive relationship between the knowledge absorption capacity, agility, and innovation performance of firms mediated by big data analytics and DP capabilities. Flexibility orientations also showed a significant moderating role, but the role of data-driven culture was not significant. Statistical results reject the hypothesis. This study enriches the scope of the theories mentioned above and comes up with several other interesting theoretical and managerial implications valuable for academicians and policymakers.