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Background In recent years, studies have demonstrated the use of ultrasound speckle tracking techniques for the early evaluation of subclinical left ventricular (LV) systolic function in patients with type 2 diabetes mellitus (T2DM). In addition, long-term exposure to hyperglycemia severely damages the microvascular system. However, the interaction between diabetic microvascular complications and subclinical LV systolic function has not been fully understood. Objective To investigate the relationship between subclinical LV systolic function and diabetic microvascular complications in patients with T2DM. Methods A total of 150 patients with T2DM who were admitted to the Department of Endocrinology, the First Affiliated Hospital of Air Force Medical University from June to December 2021 were selected in the cross-sectional study and all underwent conventional echocardiography, pulsed tissue Doppler echocardiography and two-dimensional speckle tracking echocardiography (2D STE). The 2D global longitudinal strain (GLS) of LV was obtained to assess the subclinical LV systolic function. Diabetic microvascular complications were defined as combined diabetic retinopathy, diabetic kidney disease or peripheral neuropathy. The subjects were divided into the T2DM alone group (T2DM alone group, n=76), the T2DM with 1 complication group〔T2DM+C (1) group, n=37〕 and the T2DM with 2 to 3 complications group〔T2DM+C (2 to 3) group, n=37〕 according to the cumulative number of microvascular complications. The general demographic characteristics and biochemical indices of patients in the three groups were compared. The relationship between microvascular complications and subclinical LV systolic function was assessed by using Spearman correlation analysis and Logistic regression analysis. Results GLS was lower in the T2DM+C (1) and T2DM+C (2 to 3) groups than in the T2DM alone group (P

As a magical material with powerful functions, graphene has recent high strength, excellent thermal conductivity, and good biological compatibility. In recent years, it has attracted the attention of the scientific and public worlds. Considering the prospects of extensive research in graphene, this paper uses the results of the predecessor used in the panoramic method to summarize the research and application of graphene. Specifically, this paper introduces the basic information of graphene including the simple concepts, structures, and main preparation methods. The advantages and weaknesses of different preparation methods (Mechanical Exfoliation Method, Redox method, Exogenous extension method (SiC), Liquid Phase Epitaxy, Vapor deposition method, and Solvothermal method) are compared. In terms of applications, this paper summarizes graphene applied in the current anode materials of the battery, and the field of medical application (dental planting, bone tissue engineering project). The current production rate of graphene is low, the quality of graphene is not high, and the quality of graphene is low. On this basis, and the aspect of the performance of graphene improvement has been outlooked.

The test of face gear transmission under the high- speed and heavy- load requires high performance test equipment. In order to simplify the experiment condition and reduce test cost,the similarity theory of the tooth root bending stress and vibration acceleration is obtained based on the dimensional analysis theorem. The tooth root bending stress and vibration acceleration of face gear under high- speed and heavy- load conditions are measured by the experiment. The bending stress and vibration acceleration of face gear under high- speed and heavy- load conditions are estimated by using the analogical relationship between the face gear prototype and the similarity model establishing with similarity criterion. The prediction of strength and dynamic performance of high- speed and heavy- load face gear under the is realized.

In order to study the mechanical properties of steel fiber rubber recycled brick concrete, ten groups of recycled brick concrete specimens with the strength of 15MPa were tested , one group was purely recycled brick concrete, the remaining nine groups mixed with different rations of admixture. Three groups mixed with steel fiber, another three groups mixed with rubber granules, the last three groups mixed with both steel fiber and rubber granules. These concrete specimens were tested by pressure testing machine respectively, the maximum strength is calculated by its maximum stress value. The results proved that: when adding steel fiber to recycled brick concrete can improve the strength of concrete, the higher the percentage of steel fiber was added, the more obvious the increases in strength. The recycled brick concrete mixed with rubber granules showed a reduced strength of the concrete, the higher percentage of rubber granules were added, the more significant drop in strength. When added the same percentage of both steel fiber and rubber granules, the result showed an increased strength of recycled brick concrete, as the percentage of two kinds of admixture dosage increases simultaneously, the strength increases rapidly.

Based on the basic principles of heat transfer and thermal elastic- plastic theory,by using finite element method,the heat treatment analytical model of spiral bevel gear is established. The influence of carburizing quenching process on tooth residual stress distribution and deformation is simulated by DEFORM software. The variation law of microstructure,residual stress and tooth deformation with time in the carburizing quenching process are obtained. The influence of different quenching temperature on tooth residual stress,deformation and performance is researched. The simulation results show that the compressive stress on tooth surface and the tensile stress on core portion are formed after heat treatment. The tooth surface residual compressive stress is increased with the quenching temperature. This can improve the fatigue property and performance of spiral bevel gear. The analysis of tooth surface deformation can provide certain theoretical guidance for the subsequent spiral bevel gear grinding process parameter.

Aiming at the problem of load test data volume of transmission system of heavy tracked vehicles（HTVs） is huge and extraction rate of effective information is low,the inherent fractal hierarchical rule of this data is studied,this data have the typical fractal characteristic is verified and the fractal parameter of the tracked vehicle transmission system load data under a certain road condition.Under the premise of ensurse data accuracy and fractal character,a new fractal interpolation method（FIM） is built,the continuation to simplify data information is realized.Moreover,obvious advantages could be observed in the results of the FIM,comparing to those of the linear interpolation method and the spline interpolation method.It could be concluded that by combining a’low-frequency-and-long- time’ sampling approach and the proposed FIM,the test efficiency of load history can be improved,the complex chaotic feature of high frequency sampling data can be represented.And a analysis way for researching the dynamic chaos characteristic of the HTVs transmission system is provided.

The problem of road traffic safety has been widely concerned in recent years. The identification of traffic accident hot spots can effectively improve the road traffic safety and let the traffic managers formulate targeted improvement measures and suggestions. The traditional identification method of accident hot spot does not consider the spatial attribute of the accident, so it has some limitations in the identification of traffic accident hot area. Therefore, this paper first proposes a method to identify the hot spot of traffic accidents based on geographic information system (GIS). The mathematical model and machine learning model are used to explore the correlation between traffic accidents and spatial characteristics from macro and micro aspects. Finally, taking Beijing as an example, the feasibility of the research method is proved by using the accident data of Beijing in 2015 and the geographic information of Beijing. The research results of this paper can realize the spatial effective transformation of accident records, comprehensively consider the micro and macro attributes of the accident itself, realize the automatic and efficient identification of the accident hot spot. In addition, the causality analysis results between each attribute and the distribution of accident hot spots can help decision makers to formulate safety and sustainable road strategies.

The NC machining simulation and virtual measurement of spiral bevel gear is carried out based on the VERICUT.Firstly,the coordinate transformation principle of traditional machine and NC machining principle are introduced.Then the tooth cutting simulations of the large gear of spiral bevel gear are carried out by using VERICUT.Secondly,the three-dimensional model is reversely built by means of UG software and the generated coordinates of tooth surface points.Finally,the simulation tooth cutting model is measured and contrasted with UG design model to verify the feasibility of NC processing method.Meanwhile,it also offers shortcuts to the actual NC machining of the gear,and greatly shortens the cycle from design to production,thus improving the production efficiency of spiral bevel gear.

Multimodal public transport network (MPTN) plays an important role in relieving road traffic pressure for metropolitan area. Nevertheless, the impact of an accident happened in an individual station may not only disrupt the station itself or the single lines that go through the station but also spread over the whole network. Therefore, identifying the vulnerable stations is essential for improving the MPTN management against the systematic risk caused by accidents. In this paper, we proposed a route diversity-based approach to measure the vulnerability of stations in MPTN based on the complex network theory. The route constraint parameters were established to reflect the travel time restriction in constructing the set of passengers' acceptable routes. In addition, an algorithm was formulated to rapidly calculate the route diversity index and meanwhile avoid the “overlapping routes” problem. A simple virtual network was used as a numerical example to compare the proposed approach with the vulnerability evaluation approaches based on degree centrality and betweenness centrality. Finally, the proposed approach was applied to the MPTN of Beijing to explain its effectiveness and potential applications. The results show that the proposed method can efficaciously estimate vulnerable nodes compared with degree centrality and betweenness centrality. Meanwhile, the acceptable routes between any OD pairs in the MPTN are 1-10 according to the constrained parameter. In addition, the average number of acceptable routes between OD pairs of Beijing MPTN is 3.649. By ranking the stations according to their vulnerability, it can be found that the top 5 vulnerable stations are all external traffic hubs or the stations around famous commercial areas. The results suggest that these stations are significant for external transport as well as crucial for internal urban transportation systems. The research output could contribute to the MPTN management in accident prevention and emergency handling., Author(s): Jianlin Jia (corresponding author) [1]; Yuwen Huang [1]; Wanting Zhang [1]; Yanyan Chen [2]; Zhuo Liu [2] 1. Introduction Due to the rapid urbanization all over the world, a [...]

Background The association between years of non-diabetes status after diagnosis of impaired glucose tolerance (IGT) and the risk of long-term death and cardiovascular outcomes needed to be clarified. Methods and findings In this post hoc analysis, we included 540 individuals with IGT who participated in the original Da Qing Diabetes Prevention Study (DQDPS). In the DQDPS, all participants were diagnosed with IGT by a 75 g oral glucose tolerance test and randomized to intervention or control groups with a 6-year lifestyle intervention trial. After the completion of the trial, death, cardiovascular events, and microvascular complications were monitored over a 30-year follow-up. In this post hoc analysis, the Cox analysis assessed the extended risk of these outcomes in individuals who either remained non-diabetes status or progressed to diabetes at the end of 2, 4, and 6 years after diagnosis of IGT. In all participants, the difference in the cumulative incidence rate of the outcomes between the diabetes and non-diabetes group gradually increased over 30 years. Compared with the diabetes group, a significantly lower risk of all-cause death (hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.57 to 0.97, p = 0.026), cardiovascular events (HR: 0.63; 95% CI: 0.49 to 0.82, p < 0.001), and microvascular complications (HR: 0.62; 95% CI: 0.45 to 0.86, p = 0.004) first emerged in individuals who remained non-diabetes at the 4 years visit, whereas the significant risk reduction in cardiovascular death was first observed at the end of 6 years (HR: 0.56; 95% CI: 0.39 to 0.81, p = 0.002) after adjustment for age, sex, smoking status, BMI, systolic blood pressure, blood glucose, total cholesterol, intervention, and medications (including insulin plus oral hypoglycaemics, antihypertensives, and lipid-lowering agents). The results in the original intervention group alone were similar to the whole group. The main limitations of our study are the limited number of participants and the sole ethnicity of the Chinese population. Conclusions In this study, we observed that maintaining several years of non-diabetes status after IGT diagnosis was associated with a significant reduction in long-term risk of death and vascular complications, and for most of these outcomes, maintaining at least 4 years of non-diabetes status may be needed to achieve a significant risk reduction., Author(s): Xin Qian 1, Jinping Wang 2, Qiuhong Gong 1, Yali An 1, Xinxing Feng 1, Siyao He 1, Xiaoping Chen 3, Wenjuan Wang 4, Lihong Zhang 1, Yuanchi Hui [...]

Drivers' fault emergency response behavior can easily lead to crashes, resulting in significant economic and property losses. Exploring the causes of improper emergency response behavior is crucial for regulating driver behavior and preventing crash. Therefore, based on crashes data between commercial motor vehicles (CMVs) and noncommercial motor vehicles (NCMVs) that occurred in China from 2014 to 2018, this study established a binary logistic regression model. It systematically analyzed the key factors influencing drivers' fault emergency response behaviors in terms of individuals, vehicles, road conditions, environment, and corporate management. Additionally, it compared the differences in the influencing factors of fault emergency response behaviors between drivers of CMV and NCMV. The results indicate that the model fits well. The presence of faulty emergency response behavior in drivers is significantly correlated with five factors: age, gender, fatigue driving, speeding, and weather conditions. Moreover, these factors have different impacts on CMV drivers and NCMV drivers. Fatigue driving and speeding have a more significant impact on CMV drivers, while other factors are more pronounced for NCMV drivers. This study can provide valuable insights for the development of measures aimed at reducing the severity of CMV-NCMV crashes., Author(s): Panyi Wei [1,2,3,4]; Jianling Huang [5]; Yanyan Chen (corresponding author) [1,2]; Jianming Ma [6]; Yunchao Zhang [1,2]; Shaohua Wang [7]; Ning Chen [1,2] 1. Introduction In recent years, crashes [...]

Negative interpersonal attitudes can affect people's well-being, interpersonal relationships, and cooperation. Overcoming negative interpersonal attitudes is a key subject in loving-kindness and compassion meditations (LCMs). However, the results and study design of previous research on negative interpersonal attitudes have been inconsistent. Therefore, it is necessary to summarize the effects of LCMs and explore moderators through meta-analysis. A literature search was conducted in the Cochrane Central Register of Controlled Trials, ISI Core Collection, Medline, ProQuest Dissertations & Theses, and PsycINFO databases up to April 2, 2021. Of the 281 identified empirical studies on LCMs, 25 measured negative interpersonal attitudes, and 21 were included in the meta-analysis. The results showed that the effects of LCMs on negative interpersonal attitudes in daily life were significant both for randomized controlled trials (g = -.203) and uncontrolled trials (g = -.539). The instant effects after meditation were also significant in randomized controlled experiments (g = -.187). Leave-one-out sensitivity analysis and nonsignificant subgroup analysis showed that the results were robust except for randomized controlled experiments. Although no significant moderators were identified, moderator analysis suggested that reducing bias and sending wishes to difficult targets were especially effective, and LCM subtypes might impact the results. Individual studies found that the contribution of meditation practice during interventions was weak. In sum, LCMs have the potential to reduce negative interpersonal attitudes, especially in multiweek interventions. Future studies should further explore the underlying mechanisms and consider the implications of study design features, such as the induction of negative interpersonal attitudes and the targets of LCMs., Author(s): Jingyi Zhou [sup.1] , Yongqi Lang [sup.1] , Zilin Wang [sup.1] , Chenyu Gao [sup.1] , Jing Lv [sup.2] , Yuan Zheng [sup.1] , Xiaodan Gu [sup.1] , Luyi [...]