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For continuous steel–concrete composite girder bridges based on the post-combined method, the conventional rectangular group studs contribute to the isolation of the steel girder and the concrete slab before prestressing, leading to the majority of prestress forces being introduced to the concrete slab. However, rectangular-group stud holes cause the prestress forces to be unevenly distributed. In this study, a new type of bellow-sleeved stud (BSS) was developed to mitigate the weakening effects of rectangular group stud holes on the slab. A steel corrugated sleeve with a diameter of 60 mm was employed to cover the stud, which served as an internal formwork to prevent the concrete from bonding with the root of the stud. After prestressing was complete, the steel sleeve was filled with ultra-high-performance concrete (UHPC) to create a reliable combination between the concrete slab and the steel girder. To investigate the shear performance of this new type of connection, eight push-out test specimens were designed, and finite-element models were built. This study drew a comparison between the BSS and the ordinary headed stud (OHS). The research findings suggested that the BSS is subjected to less bending–shear coupling and offers a 4.5% increase in shear strength and a 31.9% increase in shear stiffness compared with the OHS. The study also analyzed the structural parameters influencing the shear performance of the BSS. It is found that the steel sleeve of the BSS has a negative effect on shear performance, but this can be mitigated by infusing high-strength material into the sleeve. Furthermore, the study examined the effect of construction quality on shear performance and suggested that sleeve deviation and grout leakage considerably reduced the shear performance of the BSS. Accordingly, strict control over the construction quality of the BSS is necessary.

The effect of aftershocks on the function recovery process of damaged structures after large earthquakes cannot be ignored in the resilience evaluation of buildings and communities. Based on the Monte Carlo simulation method, this paper proposes an approach to evaluate the seismic resilience of reinforced concrete frame considering the effect of mainshock-aftershock sequences. The findings of this study can provide a reference for the seismic performance evaluation of reinforced concrete frame structures under aftershocks.

In modern civil aeroengines, the hot streak and swirl at the exit of the combustor have a significant impact on the aerothermal performance of the high-pressure turbine (HPT). Due to the different design purposes of the combustor and the turbine, hot streak (HS) and swirl (SW) have different spatial distributions at the turbine inlet. This paper conducts a transient simulation of the GE E3 first-stage HPT, considering the swirl and hot streak facing the middle of the passage and the leading edge of the nozzle guide vane, respectively, and also explores the impact of positive and negative swirl. The results show that different clocking positions and swirl directions will change the incident angle and streamline distribution of the vane, thereby affecting the migration of the hot streak, the temperature and the Nusselt number distribution on the stator surface. In positive cases, the hot streak gathers in the upper part of the passage, and in negative cases, it is in the lower part. In middle cases, high-temperature areas appear in both vanes, and the distributions are opposite. Affected by the swirl, when facing the passage center, the pressure side stagnation lines of the two vanes are also different, so the Nusselt number distribution is opposite. When facing the leading edge, only one vane appears. Due to the insensitive interference of the rotor–stator, the transient migration of the hot streak in the rotor is mainly affected by the inherent secondary flow and the temperature at the inlet of the rotor (especially the conditions facing the leading edge), while the upstream residual swirl is less affected. Unlike the middle case, in leading edge cases, the hot streak is separated and needs to be re-mixed before entering the blade passage, so the temperature change in the blade cascade is relatively gentle. Based on this, the Nusselt number distribution on the surface of the blade is similar. In order to obtain the most favorable operating conditions for the engine, the turbine efficiency is used to compare the aerothermal performance under different conditions. Ultimately, it was found that the turbine with the hot streak and positive swirl directly facing the leading edge was the most efficient.

The attitude tracking synchronization control of an orbit-predetermined leader–follower spacecraft swarm for the space moving target is discussed in this paper. The information exchange between all spacecraft is assumed to be discrete in time and on the undirected connected graph. Moreover, due to the demand for saving communication resources, wireless interference has been utilized, which allows all the neighbors of a spacecraft to access the same channel frequency spectrum simultaneously. Then the backstepping control algorithm is designed to let the spacecraft (β,A)-practically stably synchronize their states and track a time-varying trajectory in the presence of unknown fading channels. Finally, simulation is provided to verify that using the proposed control scheme, the attitude tracking synchronization can be achieved with high precision.

Dental follicle progenitor/stem cells (DFPCs) are a group of dental mesenchyme stem cells that lie in the dental follicle and play a critical role in tooth development and maintaining function. Originating from neural crest, DFPCs harbor a multipotential differentiation capacity. More importantly, they have superiorities, including the easy accessibility and abundant sources, active self-renewal ability and noncontroversial sources compared with other stem cells, making them an attractive candidate in the field of tissue engineering. Recent advances highlight the excellent properties of DFPCs in regeneration of orofacial tissues, including alveolar bone repair, periodontium regeneration and bio-root complex formation. Furthermore, they play a unique role in maintaining a favorable microenvironment for stem cells, immunomodulation and nervous related tissue regeneration. This review is intended to summarize the current knowledge of DFPCs, including their stem cell properties, physiological functions and clinical application potential. A deep understanding of DFPCs can thus inspire novel perspectives in regenerative medicine in the future.

Pancreatic ductal adenocarcinoma (PDAC) elicits a dense stromal response that blocks vascular access because of pericyte coverage of vascular fenestrations. In this way, the PDAC stroma contributes to chemotherapy resistance, and the small-sized nanocarrier loaded with platinum has been adopted to address this problem which is not suitable for loading docetaxel (DTX). In the present study, we used the poly(d,l-lactide)-b-polyethylene glycol-methoxy (mPEG-b-PDLLA) to encapsulate DTX and got a small-sized polymeric micelle (SPM); meanwhile we functionalized the SPM’s surface with TAT peptide (TAT-PM) for a higher permeability. The diameters of both SPM and TAT-PM were in the range of 15–26 nm. In vitro experiments demonstrated that TAT-PM inhibited Capan-2 Luc PDAC cells growth more efficiently and induced more apoptosis compared to SPM and Duopafei. The in vivo therapeutic efficiencies of SPM and TAT-PM compared to free DTX was investigated on the orthotopic transplantation model of Capan-2 Luc. SPM exerted better therapeutic efficiency than free DTX, however, TAT-PM didn’t outperformed SPM. Overall, these results disclosed that SPM could represent a new therapeutic approach against pancreatic cancer, but its permeability to PDAC was not the only decisive factor.

MicroRNAs (miRNAs) are small non-coding RNAs that are critical in post-transcriptional regulation. Macaca mulatta is an important nonhuman primate that is often used in basic and translational researches. However, the annotation of miRNAs in Macaca mulatta is far from complete, and there are no reports of miRNA editing events in Macaca mulatta, although editing may affect the biogenesis or functions of the miRNAs. To improve miRNA annotation and to reveal editing events of miRNAs in Macaca mulatta, we generated 12 small RNA profiles from eight tissues and performed comprehensive analysis of these profiles. We identified 479 conserved pre-miRNAs that have not been reported in Macaca mulatta and 17 species specific miRNAs. Furthermore, we identified 3386 editing sites with significant editing levels from 471 pre-miRNAs after analyzing the 12 self-generated and 58 additional published sRNA-seq profiles from 17 different types of organs or tissues. In addition to 16 conserved A-to-I editing sites, we identified five conserved C-to-U editing sites in miRNAs of Macaca mulatta and Homo sapiens. We also identified 11 SNPs in the miRNAs of Macaca mulatta. The analysis of the potential targets of 69 miRNAs with editing or mutation events in their seed regions suggest that these editing or mutation events severely changed their targets and their potential functions. These results significantly increase our understanding of miRNAs and their mutation/editing events in Macaca mulatta.