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Background: Piriformis muscle mass is rare, which is particular for intrapiriformis lipoma. Thus far, only 11 cases of piriformis muscle mass have been reported in the English literature. Herein, we encountered one patient with intrapiriformis lipoma who was initially misdiagnosed. Case presentation: The patient is a 50-year-old Chinese man. He complained of osphyalgia, right buttock pain, and radiating pain from the right buttock to the back of the right leg. Both ultrasound and magnetic resonance imaging demonstrated a cyst-like mass in the right piriformis muscle. Ultrasonography-guided aspiration was performed on this patient first, but failed. He was then recommended to undergo mass resection and neurolysis of sciatic nerve. Surprisingly, final histology revealed the diagnosis of intrapiriformis lipoma. The patient exhibited significant relief of symptoms 3 days post-surgery. Conclusion: Diagnosis and differential diagnosis of radicular pain are potentially challenging but necessary. Atypical lipoma is prone to be misdiagnosed, especially in rare sites. It is notable for clinicians to be aware of the presence of intrapiriformis lipoma to avoid misdiagnosis and inappropriate treatment. [ABSTRACT FROM AUTHOR]

In this paper, a novel precast concrete composite wall connected by tooth groove and grouted sleeve was introduced, which is produced in factories by means of structure-insulation integrated prefabrication, and the prefabrication and assembly process were presented minutely. To verify the feasibility and reliability of this novel tooth groove and grouted sleeve connection method and explore the joint connection performance and the seismic performance of the precast concrete composite wall connected by tooth groove and grouted sleeve, low-cyclic reversed loading tests with an axial compressive ratio of 0.1 were performed on two full-scale precast concrete composite walls. Moreover, the failure mode, hysteretic curve, skeleton curve, stiffness degradation, displacement ductility, energy dissipation capacity, and reinforcement strain were comprehensively discussed. The research results showed that under the vertical axial load and low-cyclic reversed load, the distributed reinforcements in the wall panel only played a structural role, while the connecting reinforcements at horizontal joints can always effectively transfer stress without bond failure, and the tooth groove and grouted sleeve connection performance was reliable. In addition, the hysteretic curves of the precast concrete composite wall connected by tooth groove and grouted sleeve were full, showing good ductile deformation capacity and energy dissipation capacity. In general, the precast concrete composite wall connected by tooth groove and grouted sleeve not only possessed favorable seismic performance but also showed obvious advantages such as green energy saving, high assembly rate, and less on-site wet operation, which can be applied to practical engineering under reasonable design. [ABSTRACT FROM AUTHOR]

In order to explore the horizontal joint connection performance of the innovative tooth groove connection and vertical reinforcement lapping in the reserved hole, five horizontal joint specimens were designed and constructed in this paper. Through the combination of monotonic horizontal load tests and finite element simulation analysis, the effects of axial compression ratio, vertical reinforcement connection degree, reserved hole type, mortar strength, and tooth groove depth on the horizontal joint connection performance of innovative tooth groove connections and vertical reinforcement lapping in reserved holes were comprehensively analyzed and discussed. The results indicated that the specimens were subjected to penetration failure at the tooth groove joint, but the vertical reinforcements and UHPC in reserved holes can effectively transfer the stress, ensuring satisfactory connection performance. With the increase in axial compression ratio and vertical reinforcement connection degree, the joint connection performance enhanced gradually, while the reserved hole type had little effect on the joint connection performance. In addition, it was found that increasing the mortar strength and the tooth groove depth can significantly improve the peak bearing capacity through finite element analysis. Finally, the optimization design suggestions for this innovative tooth groove connection and vertical reinforcement lapping in the reserved hole were given considering factors such as joint connection performance and construction assembly. [ABSTRACT FROM AUTHOR]

Rebar corrosion is the primary cause of the durability degradation of reinforced concrete (RC) structures, where non-uniform corrosion is the typical pattern in engineering. This study experimentally and numerically investigated the tensile degradation properties of non-uniform corroded rebars. Corrosion morphology was accurately determined by three-dimensional (3D) laser scanning techniques, studying the characteristics of longitudinal non-uniform corrosion. The results showed that the non-uniformity of corrosion increased with an increase in corrosion levels. From tensile tests, the differences in nominal stress–strain curves among rebars with similar average corrosion levels indicated that corrosion non-uniformity has appreciable effects on the tensile behavior of rebars. The residual load-bearing capacity of corroded rebars was dominated by the reduced critical cross-section, while residual ductility was associated with the cross-section loss throughout the entire length of rebars. The degradation relations of nominal yield and ultimate strength, ultimate strain, and elongation after fracture were better correlated to the maximum cross-section loss than to the average volume loss. Additionally, numerical calculation based on the cross-sectional areas of corroded rebars was conducted to evaluate the tensile behavior of non-uniform corroded rebars. Equivalent distribution models simulating the longitudinal non-uniform corrosion were proposed, on the basis of probability characteristics of cross-sectional areas, for practical application of the numerical method. [ABSTRACT FROM AUTHOR]

Using high strength wire (HSW) as a longitudinal reinforcement in UHPC can make full use of the outstanding properties of UHPC. In this paper, the flexural test was carried out on normal rebar-reinforced UHPC (NRRU) and HSW reinforced UHPC (HSWRU) slabs. The cracking resistance, failure modes, bearing capacity and deformation characteristics of specimens were investigated. The test results indicated that both HSWRU and NRRU specimens exhibited excellent flexural performance under concentrated loads. Fewer inclined cracks and a slower cracking development process were observed for HSWRU specimens, and brittle failure did not occur during the whole loading process. As compared to HSWRU specimens, the cracking and ultimate load of NRRU specimens increased by 24.64% and 85.47%, respectively, due to a higher reinforcement ratio. Then the theoretical method available for flexural capacity and ductility calculation was proposed, and the feasibility was substantiated through test results. In addition, the traditional deformation ductility coefficient was found to be 30% conservative against the applied energy ductility coefficient. Finally, the extensive parametric analysis revealed that the increase of the reinforcement ratio and the strength of the steel rebar significantly enhanced the ultimate capacity, while the ductility coefficient was obviously weakened. Inversely, those two factors had little impact on the cracking capacity. Moreover, section height was found to be beneficial for both the flexural capacity and ductility of specimens. [ABSTRACT FROM AUTHOR]

The research objects of this paper were the prefabricated concrete components produced by four enterprises in China, and the dimension deviation data of more than 1400 prefabricated concrete components are measured with high-precision 3D photogrammetry technology. The nonparametric Kruskal–Wallis test was carried out for the size deviation of the same type of components produced by different enterprises. The distribution characteristics of geometric parameters of typical components of prefabricated structures in China, such as beams, columns, wall boards, and composite slabs, were analyzed by using the probability statistical method. The Kolmogorov–Smirnov goodness-of-fit method was used to test the cumulative distribution function of dimension deviation, and the size distribution of fabricated components was studied. The results showed that there was no significant difference in the size deviation of the same-type component produced by different enterprises, and the range of geometric parameter uncertainty random variables was small, which was between 0.99 and 1.02. Also, the fluctuation was small, the coefficient of variation was below 0.0093, and the variability of component size deviation was small. The transverse dimension of the component shows a positive deviation, the vertical dimension of component shows a negative deviation, and the dimension deviation of prefabricated concrete components follows the normal distribution. [ABSTRACT FROM AUTHOR]

Abstract: Life Cycle Assessment was used to evaluate the environmental impacts associated with the treatment of wastewater in a wastewater treatment plant (WWTP) in Kunshan, China. CMLBaseline 2000 method was used for life cycle impact assessment using SimaPro 7.0 software. The goal of this Life Cycle Assessment study was to assess the environmental benefits and drawbacks of this WWTP in comparison with other WWTPs using different advanced treatment processes. Construction phase, operation and maintenance phase, sludge landfilling, and the transportation of chemicals to the WWTP were all taken into consideration. The LCA results of Kunshan WWTP taking renewable energy (wind power) as the energy source proposed that enhancing the effluent quality will decrease the environmental. Environmental impacts in terms of green taxes were also represented. The study revealed very different impacts for the three plants, drawing attention to the importance of the choice of the treatment process. [Copyright &y& Elsevier]

Gong, Y. and Luo, X., 2020. Design of dynamic diffusion simulation system for atmospheric pollutants in coastal cities under persistent inverse temperature. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 526–529. Coconut Creek (Florida), ISSN 0749-0208. The prediction of the dynamic diffusion of atmospheric pollutants in coastal cities under continuous inverse temperature is the key to establish the dynamic treatment of atmospheric pollutants. In view of the low accuracy of the traditional nonlinear feature estimation simulation method, a continuous inverse temperature simulation model for the dynamic diffusion of atmospheric pollutants in coastal cities under continuous inverse temperature is proposed. A self-similar regression model is constructed for the statistical information of atmospheric pollutant dynamic diffusion in coastal cities under continuous inverse temperature, and a multi-scale decomposition and factor analysis are carried out for the time series of atmospheric pollutant dynamic diffusion in coastal cities under continuous inverse temperature. The simulation results show that the model has high accuracy and good convergence in the simulation and prediction of atmospheric pollutant dynamic diffusion in coastal cities. [ABSTRACT FROM AUTHOR]

In order to find a proper treatment method for a sewage sludge disposal pit, field and laboratory investigation were conducted on the geotechnical properties of the sludge at the Changan landfill in Chengdu, China. The field investigation included borehole sampling, cone penetration tests and vane shear tests. The laboratory study involved the measurements of volume–mass relation, hydraulic conductivity, compressibility, coefficient of consolidation and shear strength for the borehole samples taken from the field. The field investigation revealed that the sludge in the disposal pit could be subdivided into three layers, i.e., top crust layer, middle fluid-like layer and deep soft plastic layer. The vane shear strength for the sludge was less than 1kPa at the fluid-like layer, and 1 and 3kPa at the deep soft plastic layer, being significantly lower than that of soft clay. Laboratory test results demonstrated that the sludge was high in organic content (18.5% to 51.8%) and water content (from 210% to 790%), and both of them exhibited a decreasing trend with depth. The variation in the organic content indicated a difference in the degree of biodegradation for the sludge at locations. The consolidation property and shear strength of the sludge exhibited a non-linear relationship to the applied consolidation pressure. The coefficient of consolidation of sewage sludge, decreasing with increasing consolidation pressure, was in an order of 10−5 cm2/s to 10−6 cm2/s, being 1–2 order lower than that of soft clay. The friction angle for the sludge increased from 10° for the pressure range from 0 to 100kPa to 15° for the pressure range from 100 to 400kPa. [ABSTRACT FROM AUTHOR]