Damping effects of different shock absorbing materials for tunnel under seismic loadings

Circular tunnels are widely used in infrastructure. Under the action of earthquakes, the destruction of circular tunnels will result in a large number of economic losses and casualties. Therefore, the study on shock absorption of tunnels is important. However, the research has not been sufficient on the effect of the damping layer on seismic response of a circular tunnel in sand. In this paper, the influence of the damping layer on the seismic response characteristics of circular tunnels in sand is studied by large-scale shaking table test. The actual El-centro wave is loaded to the model system in three directions during the tests. The input peak seismic acceleration values are 0.05 g, 0.1 g and 0.2 g. Then the effects of two different damping materials on the dynamic response characteristics of circular tunnels are analysed quantitatively. The test results show that the damping layer reduces the seismic response of the circular tunnel. The response accelerations of the tunnel bottom and crown without damping layer are greater than that with the damping layer, which indicates that damping layer absorbs the energy caused by the seismic motion. When the sponge rubber is used, the circular tunnel dynamic response is more attenuated than that with foam board. In conclusion, the shock absorbing layer can effectively reduce the seismic response of tunnel. As a result, the damage of the tunnel decreases under the earthquake. This study has clarified the isolation mechanism of the shock absorbing materials. It is recommended to use sponge rubber material as the shock absorbing layer

Formación y características de hidratación temprana del C2.75B1.25A3enelsistemabinariodeC2.75B1.25A3 en el sistema binario de C2.75B1.25A3-C2S

C2.75B1.25A3$(2.75CaO•1.25BaO• 3Al2O3• SO3) is one of the important minerals and it govern-directly the early-strength of belite-barium calcium sulphoaluminate cement. In this paper a binary system C2.75B1.25A3$-C2S is selected to investigate the formation of C2.75B1.25A3$. In the range of 1100 °C–1200 °C, the earlier formed C2S hinders the formation of C2.75B1.25A3$. On the contrary, when the temperature is in the range of 1200 °C–1350 °C, the initially formed C2S could provide a surface for the nucleation of C2.75B1.25A3$and cut down the potential barrier (?Gk*) for the heterogeneous nucleation of C2.75B1.25A3$, which contributes to its formation. Moreover, at 1350 °C, the large amount of previously formed C2S benefits the extent of formation of C2.75B1.25A3$. The possible reason was that it could prevent sulfur evaporation. In early hydration age, AFm and AFt originating from C2.75B1.25A3$ hydration are found within 2 h and 12 h under 95% RH at 1 °C, respectively, whereas C2S is unhydrated at this moment.En el cemento de sulfoaluminato de calcio y bario, el C2.75B1.25A3$(2.75CaO•1.25BaO• 3Al2 O3• SO3) es una de las principales fases, y regula directamente la resistencia inicial del cemento. En este trabajo, se ha seleccionado el sistema binario C2.75B1.25A3$-C2S para investigar la formación de C2.75B1.25A3$. En el rango de 1100 °C-1200 °C, el C2S formado anteriormente impide la formación de C2.75B1.25A3$, mientras que cuando la temperatura está entre 1200 °C-1350 °C, el C2S proporcionaría una superficie de nucleación de C2.75B1.25A3$reduciendo la barrera de potencial (?Gk*) para la nucleación heterogénea de C2.75B1.25A3$, lo que contribuye a su formación. Además, a 1350 °C, la gran cantidad de C2S formado beneficia la formación de C2.75B1.25A3$, ya que podía prevenir la evaporación del azufre. En las primeras etapas de la hidratación (entre 2 y 12h y 95$, mientras que el C2S permanece sin hidratar

Link-level simulator for 5G localization

Channel-state-information-based localization in 5G networks has been a promising way to obtain highly accurate positions compared to previous communication networks. However, there is no unified and effective platform to support the research on 5G localization algorithms. This paper releases a link-level simulator for 5G localization, which can depict realistic physical behaviors of the 5G positioning signal transmission. Specifically, we first develop a simulation architecture considering more elaborate parameter configuration and physical-layer processing. The architecture supports the link modeling at sub-6GHz and millimeter-wave (mmWave) frequency bands. Subsequently, the critical physical-layer components that determine the localization performance are designed and integrated. In particular, a lightweight new-radio channel model and hardware impairment functions that significantly limit the parameter estimation accuracy are developed. Finally, we present three application cases to evaluate the simulator, i.e. two-dimensional mobile terminal localization, mmWave beam sweeping, and beamforming-based angle estimation. The numerical results in the application cases present the performance diversity of localization algorithms in various impairment conditions

Exploring Winograd Convolution for Cost-effective Neural Network Fault Tolerance

Winograd is generally utilized to optimize convolution performance and computational efficiency because of the reduced multiplication operations, but the reliability issues brought by winograd are usually overlooked. In this work, we observe the great potential of winograd convolution in improving neural network (NN) fault tolerance. Based on the observation, we evaluate winograd convolution fault tolerance comprehensively from different granularities ranging from models, layers, and operation types for the first time. Then, we explore the use of inherent fault tolerance of winograd convolution for cost-effective NN protection against soft errors. Specifically, we mainly investigate how winograd convolution can be effectively incorporated with classical fault-tolerant design approaches including triple modular redundancy (TMR), fault-aware retraining, and constrained activation functions. According to our experiments, winograd convolution can reduce the fault-tolerant design overhead by 55.77\% on average without any accuracy loss compared to standard convolution, and further reduce the computing overhead by 17.24\% when the inherent fault tolerance of winograd convolution is considered. When it is applied on fault-tolerant neural networks enhanced with fault-aware retraining and constrained activation functions, the resulting model accuracy generally shows significant improvement in presence of various faults

MiR–20a-5p promotes radio-resistance by targeting Rab27B in nasopharyngeal cancer cells

Additional file 3: Figure S2. The protein level of PARP and caspase3 detected by western in NCM, 5PM, NCA, 5PA, si-NC and si-Rab27B transfected CNE-2 and CNE-1 cells respectively

Double lung transplantation for end-stage Kartagener syndrome: A case report and literature review

Kartagener syndrome (KS) is an autosomal recessive disorder characterized by situs inversus, paranasal sinusitis and bronchiectasis. We report the successful use of double lung transplant (DLTx) to treat end-stage KS. A 49-year-old Han woman was admitted to Renmin Hospital (Wuhan University, China) in September 2017 with a ≥15 year history of chronic productive cough that had worsened during the past year. Clinical examination and imaging investigations revealed respiratory failure and situs inversus consistent with KS. The patient was successfully treated with DLTx involving bilateral bronchial anastomoses. DLTx is a feasible treatment option for end-stage KS

Hybrid minigene splicing assay verifies the pathogenicity of a novel splice site variant in the COL1A1 gene of a chinese patient with osteogenesis imperfecta type I

Abstract(#br)Background(#br)Osteogenesis imperfecta (OI) is a rare genetic bone disease associated with brittle bones and fractures. Among all known types, OI type I is the most common type and characterized by increased bone fragility, low bone mass, distinctly blue-gray sclera, and susceptibility to conductive hearing loss beginning in adolescence. Mutations in genes encoding type I collagen ( COL1A1 and COL1A2 ) contribute to the main pathogenic mechanism of OI.(#br)Methods(#br)Subtle mutation of the COL1A1 gene in the proband was detected by targeted next-generation sequencing (NGS) and confirmed by Sanger sequencing. We then assessed the effect of the mutation on the splicing of the COL1A1 gene by bioinformatics prediction and hybrid minigene splicing assay (HMSA).(#br)Results(#br)A novel splice site mutation c.1821+1 G > C was discovered in the proband by NGS and further confirmed by Sanger sequencing, which was also simultaneously identified from the proband’s mother and elder sister. Bioinformatics predicted that this mutation would result in a disappearance of the 5′ donor splice site in intron 26, thereby leading to abnormal splicing and generation of premature stop codon. The follow-up experimental data generated by HMSA was consistent with this prediction.(#br)Conclusion(#br)Our study identified a novel splice site mutation that caused OI type I in the proband by abnormal splicing and demonstrated that combined applications of NGS, bioinformatics and HMSA are comprehensive and effective methods for diagnosis and aberrant splicing study of OI

Correlation between tibial valgus deformity and aspect ratio of resected tibial surface in female Chinese patients undergoing total knee arthroplasty

BackgroundMorphology of the resected tibial surface is the reference for tibial component design, selection, and implantation in total knee arthroplasty (TKA). This comparative study sought to answer whether valgus deformity of the tibia would affect the morphology of the resected tibial surface in TKA.MethodsThirty-one female Chinese patients with valgus tibias were retrospectively and consecutively identified from a single-center registration database. Thirty-one patients with well-aligned tibias were matched in terms of gender, height, and weight. Weight-bearing full-length radiographs and computed tomography images of the whole lower limb were obtained for every case. Tibial resection was mimicked perpendicular to the mechanical axis of the tibia in the frontal plane with 3° of posterior slope and a cut level individualized by the actual intraoperative cut. On the resected surface, mediolateral dimension (MLD), medial anteroposterior dimensions (mAPD), and lateral anteroposterior dimensions (lAPD) were measured, and aspect ratios (AR) were calculated. We compared the AR between the two groups.ResultsThe aspect ratio of resected tibial surface positively correlated with tibial valgus alignment. Patients with valgus tibias had significantly smaller AR (MLD/mAPD) for the medial plateau (1.50 ± 0.06 vs. 1.54 ± 0.07, P = 0.032). However, the AR for the lateral plateau was similar between the two groups (1.63 ± 0.08 vs. 1.65 ± 0.07, P = 0.328).ConclusionThis difference in morphology of resected tibial surface between valgus and well-aligned tibias should be considered in tibial component design, as well as in the selection and placement of TKA implants for knees with valgus tibias

Lithium Chloride Suppresses Colorectal Cancer Cell Survival and Proliferation through ROS/GSK-3 β

Glycogen synthase kinase-3β (GSK-3β), a serine/threonine protein kinase, has been regarded as a potential therapeutic target for multiple human cancers. In addition, oxidative stress is closely related to all aspects of cancer. We sought to determine the biological function of lithium, one kind of GSK-3β inhibitors, in the process of reactive oxygen species (ROS) production in colorectal cancer. In this study, we analyzed the cell apoptosis and proliferation by cell viability, EdU, and flow cytometry assays through administration of LiCl. We used polymerase chain reaction and Western blotting to establish the effect of GSK-3β inhibition on the nuclear factor-κB (NF-κB) pathway. Results showed administration of LiCl increased apoptosis and the level of ROS in colorectal cancer cells. Furthermore, the underlying mechanisms could be mediated by the reduction of NF-κB expression and NF-κB-mediated transcription. Taken together, our results demonstrated that therapeutic targeting of ROS/GSK-3β/NF-κB pathways may be an effective way for colorectal cancer intervention, although further preclinical and clinical testing are desirable