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Mesenchymal stromal cells (MSCs) play an important role in the development of human cancer. Meanwhile, exosomes released by MSCs can mediate cell–cell communication by delivering microRNAs (miRNAs/miRs). Hence, this study aimed to explore the role of bone marrow mesenchymal stromal cell (BMSC)-derived exosomal miR-551b-3p in breast cancer. In this study, we found that upregulation of miR-551b-5p suppressed the proliferation and migration and induced the apoptosis of breast cancer cells via downregulating tripartite motif-containing protein 31 (TRIM31). In addition, miR-551b-5p could be transferred from BMSCs to breast cancer cells via exosomes; BMSC-derived exosomal miR-551b-3p suppressed the proliferation and migration and promoted the apoptosis and oxidative stress of MDA-MB-231 cells via inhibiting TRIM31. Furthermore, a xenograft mouse model was used to explore the role of BMSC-derived exosomal miR-551b-3p in vivo. We found that BMSC-derived exosomal miR-551b-3p inhibited tumor growth in a mouse xenograft model of breast cancer in vivo. Collectively, these findings indicated that BMSC-derived exosomal miR-551b-3p could suppress the development of breast cancer via downregulating TRIM31. Thus, miR-551b-3p could serve as a potential target for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Laser-induced damage of compression gratings has become the shortest stave for petawatt (PW) laser facilities, as it is hard to manufacture large enough meter-sized gratings with high damage threshold. Multistep pulse compressor (MPC) was proposed to improve the peak power of PW lasers recently. Using the asymmetric four-grating compressor (AFGC) to replace both of the prism-pair-based pre-compressor and typical four-grating compressor (FGC)-based main compressor, the typical three-step MPC is simplified to two steps, and can be easily extended to all PW lasers by simply reducing and increasing same amount of suitable distances of the two grating pairs, respectively. Furthermore, the AFGC will induce spatial dispersion and direct smooth the laser beam on the last grating, which is the easiest to be damaged one, and then protect it away from damage and increase the operating safety straightly. More than 100 PW can be achieved without beam combination theoretically using the AFGC-based two-step MPC method with currently available biggest gold-coated gratings. [ABSTRACT FROM AUTHOR]

M7 block of Santanghu oilfield is an abnormal low temperature tight oil reservoir. The effective development is very difficult. In this paper, we develop a new composite viscosity reducer called CSY-1. The synergistic effect of these agents provides the reducer with both dispersion and emulsification capacities. Based on orthogonal experiment and cost evaluation, the optimum formula of CSY-1 is 0.5% OP-10, 1.8% SDBS, 0.1% Tween 80, and 1% NaOH (or Na2CO3). The rheology property of heavy oil changed fundamentally before and after the addition of CSY-1. Oil-in-water emulsion with very low viscosity can be obtained and the viscosity reduction rate can be over 99%. Simulation results showed that the oil production of a single well can be increased from the current 3.74 t/d to 8.12 t/d with the application of this reducer. [ABSTRACT FROM AUTHOR]

Detailed airflow information around a building can be crucial for the design of naturally ventilated systems and for exhaust air dispersion practices in agricultural buildings like greenhouses and livestock buildings. Full-scale measurements are cost-intensive and difficult to achieve due to varied wind conditions. A common method to gain insight of flow field under different wind conditions is the numerical simulation by using computational fluid dynamics (CFD). Still, evaluation of a CFD models' performance and validation of its predictions with high quality experimental data is necessary before the model is used in practice. In this research three types of common agricultural buildings, arched-type, pitched-type and flat-type roof, were examined by conducting experiments in a wind tunnel with controlled airflow conditions, in order to validate different 3D turbulence models for predicting airflow patterns. The focus of this work was the detailed description of the external airflow field over the varied roof geometries and especially the velocity distribution and turbulent kinetic energy in the wake of each building. Experimental measurements of velocity were performed with a Laser Doppler Anemometer (LDA) and were compared with 3D RANS turbulence models' simulation results. A reasonable agreement was found between experimental and simulation results concerning the velocity and the turbulence kinetic energy with CFD models slightly underestimating these magnitudes. The k- ε series turbulence models and especially the standard k- ε, RNG k- ε and Realizable k- ε models presented good agreement concerning velocity contours; however, high prediction error occurred over the roof of the buildings compared to the average values. [ABSTRACT FROM AUTHOR]

The environmental control system (ECS) of a commercial airplane supplies air to the cabin in order to maintain a safe, comfortable, and healthy environment for passengers and crew members. Because about half of the air supplied to the cabin is outside air, atmosphere particles could deposit in the ECS before entering the cabin. This investigation developed a model to calculate the particle deposition rates in the ECS for different particle sizes on the basis of a set of empirical equations from the literature. The model was used to predict particle deposition in five types of commercial airplanes (a regional jet, Boeing 737-800, Airbus 319, Airbus 320, and MD-82). The predicted results were compared with data measured in-flight or during operation on the ground and agreed well with the measured data. Both the simulated and measured results showed that almost all the large particles ( d ≥ 5.0 μm) and 75% of small particles ( d = 0.3-5.0 μm) were deposited in the ECS. Most of the particle deposition occurred near the entrance to the ECS where the geometry was the most complex. [ABSTRACT FROM AUTHOR]

Commercial aircraft use environmental control systems (ECSs) to control the thermal environment in cabins and thus ensure passengers' safety, health, and comfort. This study investigated the interaction between ECS operation and cabin thermal environment. Simplified models were developed for the thermodynamic processes of the key ECS components in a commercial software program, ANSYS Simplorer. A computational fluid dynamics (CFD) program, ANSYS Fluent, was employed to simulate the thermal environment in a cabin. Through the coupling of Simplorer and Fluent, a PID control method was applied to the aircraft ECS in Simplorer to achieve dynamic control of the temperature of the supply air to the cabin, which was used as a Fluent input. The calculated supply air temperature agreed with the corresponding experimental data obtained from an MD-82 aircraft on the ground. The coupled model was then used to simulate a complete flight for the purpose of studying the interaction between ECS operation and the cabin thermal environment. The results show that the PID controller in the ECS can maintain the cabin air temperature within ±0.6 K of the set point, with an acceptable air temperature distribution. The coupled models can be used for the design and analysis of the ECS and cabin thermal environment for commercial airplanes. [ABSTRACT FROM AUTHOR]

This paper describes an underwater 3500 m electric manipulator (named Huahai-4E, stands for four functions deep ocean electric manipulator in China), which has been developed at underwater manipulation technology lab in Huazhong University of Science and Technology (HUST) for a test bed of studying of deep ocean manipulation technologies. The manipulator features modular integration joints, and layered architecture control system. The oil-filled, pressure-compensated joint is compactly designed and integrated of a permanent magnet (PM) brushless motor, a drive circuit, a harmonic gear and an angular feedback potentiometer. The underwater control system is based on a network and consisted of three embedded PC/104 computers which are used for servo control, task plan and target sensor respectively. They communicate through User Datagram Protocol (UDP) multicast communication in Vxworks OS. A supervisor PC with a virtual 3D GUI is fiber linked to underwater control system. Furthermore, the manipulator is equipped with a sensor system including a unique ultra-sonic probe array and an underwater camera. Autonomous grasp strategy based multi-sensor is studied. The results of watertight test in 40 MPa, joint's efficiency test and autonomous grasp experiments in tank are also presented. [ABSTRACT FROM AUTHOR]

Porous sol-gel glass of CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by adding stearic acid as pore former when the sintering was carried out at 700 °C for 3 h. The sol-gel porous glass shows an amorphous structure. The diameter of the pore created by pore former varies from 100 to 300 μm, and macroporous glass has a narrow and small pore size distribution in mesoporous scale. The porosity and pore size of macroporous bioactive glass can be controlled. [ABSTRACT FROM AUTHOR]

Poly-L-lactide(PLLA) was synthesized by ring-opening polymerization from high purity L-lactide with tin octoate as initiator, and characterized by means of infrared, and 1H-nuclear magnetic resonance. The influences of initiator concentration, polymerization temperature and polymerization time on the viscosity average molecular mass of PLLA were investigated. The effects of different purification methods on the concentration of initiator and viscosity average molecular mass were also studied. PLLA with a viscosity average molecular mass of about 50.5×104 was obtained when polymerization was conducted for 24 h at 140 °C with the molar ratio of monomer to purification initator being 12 000. After purification, the concentration of tin octoate decreases; however, the effect of different purification methods on the viscosity average molecular mass of PLLA is different, and the obtained PLLA is a typical amorphous polymeric material. The crystallinity of PLLA decreases with the increase of viscosity average molecular mass. [ABSTRACT FROM AUTHOR]

The Reynolds stress transport equation model (DSM) is used to predict the strongly swirling turbulent flows in a liquid-liquid hydrocyclone, and the predictions are compared with LDV measurements. Predictions properly give the flow behavior observed in experiments, such as the Rankinevortex structure and double peaks near the inlet region in tangential velocity profile, the downward flow near the wall and upward flow near the core in axial velocity profiles. In the inlet or upstream region of the hydrocyclone, the reverse flow near the axis is well predicted, but in the region with smaller cone angle and cylindrical section, there are some discrepancies between the model predictions and the LDV measurements. Predictions show that the pressure is small in the near-axis region and increases to the maximum near the wall. Both predictions and measurements indicate that the turbulence in hydrocyclones is inhomogeneous and anisotropic. [ABSTRACT FROM AUTHOR]