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[Objectives] This paper aims to study the influence of welding defects on fatigue life of aluminum alloy plate frame.[Methods] Firstly,use X-ray to detect the welds of the test aluminum alloy plate frames with two gusset joints,and then select two plate frames with and without welding defects respectively. Then obtain main types of the welding defects through the analysis on the X-ray images. Then,carry out fatigue tests for these two plate frames with and without welding defects under different loads,so as to obtain the fatigue life of the plate frames. Finally,establish local FE models for the test plate frames with three types of welding defects by using ABAQUS software,and analyze and reveal the failure mechanism of the plate frames with welding defects.[Results] The test results show that,the failure of the test plate frame with welding defects is caused by the fracture on the longitudinal web due to the extension of the crack in the welding defect at the end of the weld;the failure of the test plate frame without welding defects,which is related to the gusset joint,is caused by the fracture on the longitudinal web due to the extension of the fatigue crack generated under the cyclic loads on the longitudinal web.[Conclusions] This study results can provide a reference for the assessment of the fatigue life and for the influence of the welding defects on the fatigue life.

Family and school environments are assumed to be associated with and influence aggressive behaviors. However, which specific risk factors within these environments that are associated with aggressive behavior are unclear. The goal of this study is to identify family and social environmental qualities that are related to aggression among Chinese adolescents. Survey data were obtained from 3,213 randomly selected urban high school students ages 10 through 18 in southern China. Lower parental attachment, higher family income, mother's higher education levels, father's parenting goals, rough or changeable parenting styles, unsuitable peer relationships, and inadequate social atmospheres at school serve as risk factors for aggression among Chinese adolescents. Our findings provide some implications for understanding aggression among adolescents and suggests possible interventions to help overcome potential environmental risk factors and thus to prevent aggressive behavior in school.

When residual sludge hydrothermal liquid is used as a carbon source for biological denitrification of wastewater, the effective carbon source available to microorganisms is low and the nitrogen and phosphorus loadings in the sludge hydrothermal liquid can affect the effectiveness of microbial denitrification. The effect of different pretreatment methods (alkali-catalyzed, multi-acid-catalyzed, ultrasonic and freeze-thaw treatment) on the composition of sludge hydrothermal liquid was investigated. The sludge hydrothermal liquid with good biochemical performance after aerobic biological treatment was tested for denitrification to investigate the water quality characteristics of the pretreated sludge hydrothermal liquid and its denitrification efficiency as a carbon source for denitrification. The results show that the best leaching effect of the sludge from the hydrothermal process is achieved after pretreatment with 144 W power ultrasound; H2SO4 catalysis contributes to the hydrolysis of proteins in the sludge hydrothermal liquid, and the combination of ultrasound further promotes the hydrolysis of proteins, resulting in a decrease in the ratio of organic nitrogen in the sludge hydrothermal liquid. It indicates that pretreatment by ultrasonication or acidification combined with ultrasonication can enhance the effectiveness of sludge hydrothermal liquid as a carbon source for denitrification. [ABSTRACT FROM AUTHOR]

Background: Neuroimaging studies on Parkinson's disease (PD) mainly focus on static neural activity. However, the dynamic pattern of regional brain activity in early-stage cognitively normal PD has rarely been elucidated. Purpose: To identify altered dynamic amplitude of low-frequency fluctuation (dALFF) in PD before the onset of cognitive impairment and verify its differentiating ability between patients with PD and healthy controls (HC). Material and Methods: dALFF and static ALFF (sALFF) derived from functional magnetic resonance imaging data of 51 patients with PD and 50 matched HCs were analyzed. The correlations between aberrant regions and clinical performance were investigated using Spearman correlation analysis. Multivariate pattern analysis was conducted to detect the differentiating ability of both ALFF features. Results: Compared with HCs, patients with PD demonstrated reduced dALFF variance in bilateral lingual gyrus, left middle occipital gyrus, left postcentral gyrus (PcG), and right supplementary motor area (SMA); and increased dALFF variability in bilateral parahippocampal gyrus. Besides overlapping with these distributions of altered dALFF, the aberrant regions of sALFF were more extensive with decreased sALFF in the right middle temporal gyrus and right PcG, and increased sALFF in the left inferior temporal gyrus and left thalamus were observed in patients with PD. dALFF values in right SMA and left PcG were correlated with UPDRS-III scores (ρ = −0.29, P = 0.041; ρ = −0.33, P = 0.018, respectively). Conclusion: This study provides novel insights into the neural basis underlying PD as well as the potential role of dynamic neural activity in the diagnosis and prediction of the disease. [ABSTRACT FROM AUTHOR]

This paper discusses the factors that should be considered when establishing the energy consumption evaluation index framework of building materials, and in order to facilitate the statistics and realization of the energy consumption throughout the life cycle of the building, the energy consumption process of building materials is defined as the following stages: the production and transportation of raw materials, the production and transportation stage of building materials, and the recycling stage of building materials. At the same time, this article is based on the four types of bulk building materials for civil buildings, and establishes a framework of energy consumption evaluation indicators for the production and transportation of building materials. This can better grasp the energy consumption of construction projects. [ABSTRACT FROM AUTHOR]

Background: Patients with uterine cervical cancer suffer high mortality. Accurate detection of a residual tumor by magnetic resonance imaging (MRI) during and after directed brachytherapy (BCT) is crucial for the success of cancer treatment and is a significant predictor of patient survival.Purpose: To determine the diagnostic significance of MRI in detecting residual tumor tissue after BCT.Material and Methods: The Web of Knowledge, Cochrane Library, and PubMed were systematically searched (January 1997 to December 2016) for post-brachytherapy MRI studies that measured residual tumors in patients with uterine cervical cancer. All data were analyzed using the Meta-Disc 1.4 program.Results: Four clinical studies consisting of 163 patients (147 of whom were included in the present analysis) who were diagnosed with uterine cervical cancer according to the International Federation of Gynecology and Obstetrics (FIGO) staging system were included in the study. All the patients received BCT and underwent MRI detection of residual tumors tissue. In studies where the accuracy of MRI detection was confirmed by histological tests or gynecological tests, the summary estimates of specificity, sensitivity, positive predictive value, negative predictive value, and accuracy were 88.5%, 83.5%, 53.5%, 97.1%, and 84.3%, respectively.Conclusion: MRI-directed BCT is commonly used for cervical cancer patients. Based on our investigation of four independent studies, MRI showed better prediction of positive results than negative results in patients with cervical cancer after BCT. However, more data on the greater numbers of patients are needed to establish the accuracy of MRI detection of cervical cancer after BCT. [ABSTRACT FROM AUTHOR]