54 research outputs found

    Tumor Suppressor Spred2 Interaction with LC3 Promotes Autophagosome Maturation and Induces Autophagy-Dependent Cell Death

    Get PDF
    The tumor suppressor Spred2 (Sprouty-related EVH1 domain-2) induces cell death in a variety of cancers. However, the underlying mechanism remains to be elucidated. Here we show that Spred2 induces caspase-independent but autophagy-dependent cell death in human cervical carcinoma HeLa and lung cancer A549 cells. We demonstrate that ectopic Spred2 increased both the conversion of microtubule-associated protein 1 light chain 3 (LC3), GFP-LC3 puncta formation and p62/SQSTM1 degradation in A549 and HeLa cells. Conversely, knockdown of Spred2 in tumor cells inhibited upregulation of autophagosome maturation induced by the autophagy inducer Rapamycin, which could be reversed by the rescue Spred2. These data suggest that Spred2 promotes autophagy in tumor cells. Mechanistically, Spred2 co-localized and interacted with LC3 via the LC3-interacting region (LIR) motifs in its SPR domain. Mutations in the LIR motifs or deletion of the SPR domain impaired Spred2-mediated autophagosome maturation and tumor cell death, indicating that functional LIR is required for Spred2 to trigger tumor cell death. Additionally, Spred2 interacted and co-localized with p62/SQSTM1 through its SPR domain. Furthermore, the co-localization of Spred2, p62 and LAMP2 in HeLa cells indicates that p62 may be involved in Spred2-mediated autophagosome maturation. Inhibition of autophagy using the lysosomal inhibitor chloroquine, reduced Spred2-mediated HeLa cell death. Silencing the expression of autophagy-related genes ATG5, LC3 or p62 in HeLa and A549 cells gave similar results, suggesting that autophagy is required for Spred2-induced tumor cell death. Collectively, these data indicate that Spred2 induces tumor cell death in an autophagy-dependent manner

    Study on multi-objective flexible job-shop scheduling problem considering energy consumption

    Get PDF
    Purpose: Build a multi-objective Flexible Job-shop Scheduling Problem(FJSP) optimization model, in which the makespan, processing cost, energy consumption and cost-weighted processing quality are considered, then Design a Modified Non-dominated Sorting Genetic Algorithm (NSGA-II) based on blood variation for above scheduling model. Design/methodology/approach: A multi-objective optimization theory based on Pareto optimal method is used in carrying out the optimization model. NSGA-II is used to solve the model. Findings: By analyzing the research status and insufficiency of multi-objective FJSP, Find that the difference in scheduling will also have an effect on energy consumption in machining process and environmental emissions. Therefore, job-shop scheduling requires not only guaranteeing the processing quality, time and cost, but also optimizing operation plan of machines and minimizing energy consumption. Originality/value: A multi-objective FJSP optimization model is put forward, in which the makespan, processing cost, energy consumption and cost-weighted processing quality are considered. According to above model, Blood-Variation-based NSGA-II (BVNSGA-II) is designed. In which, the chromosome mutation rate is determined after calculating the blood relationship between two cross chromosomes, crossover and mutation strategy of NSGA-II is optimized and the prematurity of population is overcome. Finally, the performance of the proposed model and algorithm is evaluated through a case study, and the results proved the efficiency and feasibility of the proposed model and algorithm

    Coordinated Symmetrical Altitude Position and Attitude Control for Stratospheric Airship Subject to Strong Aerodynamic Uncertainties

    No full text
    The stratospheric airship has important value in both commercial and military use. The altitude position control is very crucial for the airship to conduct specific missions, which is also a challenge because of both the severe relative aerodynamic mismatches and the large lag due to the quite low speed of the airship within 15 m/s. In this paper, a coordinated altitude and attitude control method was proposed to realize satisfactory altitude position control while maintaining the attitude stability by properly employing the two actuators, the propeller thrust and the elevator, in a consistent manner. In this process, the references for the vertical speed and the pitch were specified in a straightforward way of proportionating them by considering their physical characteristics and the inherent symmetrical relationship between them, which can be obtained through the kinematics. An extended disturbance observer was used to eliminate the severe aerodynamic uncertainties to symmetrically distribute the two actuator outputs by dynamically decoupling the vertical speed and the pitch angular rate loops into the two independent integrators. As a result, the explicit proportional controllers were sufficient to realize efficient command tracking. Rigorous theoretical investigation was provided to symmetrically prove the quantitative bounded property of the estimation and tracking errors. The simulation results demonstrated the effectiveness of the proposed approach, which can realize a 500-m altitude difference tracking within 200 s with less than 0.5 deg/s pitch angular rate

    Modeling and Simulation of an Electronic Oxygen Regulator Based on All- Coefficient Adaptive Control

    No full text
    Safe and reliable automatic pressure regulation of the oxygen mask is a primary consideration for the oxygen supply system. One kind of electronic oxygen regulator (EOR) structure is proposed, and its operation principle is explained in this paper. To avoid long controller design cycle, herein, some simulations are carried out on MATLAB for analysis by establishing a mathematical model according to the EOR flow dynamic characteristics. In the simulations, the all-coefficient adaptive control method based on a characteristic model (CM) and the proportional-integral-derivative (PID) algorithm are applied, and the results are thoroughly investigated by considering some disturbance, such as the user's changing pulmonary ventilation parameters, the air leakage of the mask, and the sensor noise. Results suggest that the all-coefficient control method is more effective to guarantee superior lower inspiratory resistance than the PID method with the environmental disturbance, which may be a plausible reference for the EOR controller design

    Study of manufacturing resource perception and process control of a radio-frequency-identification-enabled decentralized flexible manufacturing system

    No full text
    The fusion of mechatronics, communication, control, and information technologies has introduced new automation paradigms into the production environment. Plug-and-play flexible manufacturing systems will become suitable approaches in the future for the development of modular, flexible, and reconfigurable manufacturing systems, addressing the requirements of global markets. This article introduces a Petri Net model-driven methodology for the development, validation, and operation of a radio-frequency identification-enabled decentralized flexible manufacturing system. After analyzing the manufacturing processes and resources of a flexible manufacturing system, the manufacturing resources are classified into active and passive resources. Each active resource is equipped with a radio-frequency identification reader and each passive resource is banded with a radio-frequency identification tag. Real-time state and behavior logic models are built for manufacturing resources based on extended Petri Nets; the models are translated into XML and integrated with the manufacturing resources. In this fashion, each manufacturing resource becomes an autonomous agent, and it can make self-decisions and update its status through the twinned models. In this manner, automatic perception and process control are realized. Finally, the effectiveness and feasibility of the method are verified in an experimental system

    Chaos-Based Fuzzy Regression Approach to Modeling Customer Satisfaction for Product Design

    No full text

    A Review of the Developed New Model Biodiesels and Their Effects on Engine Combustion and Emissions

    No full text
    Biodiesel is regarded to be a renewable, CO2 neutral and thus sustainable biological alternative diesel fuel. With attention to the reduction of petroleum import, PM 2.5 aerosol particles and the greenhouse effect gas CO2, biodiesel has drawn great research interests and efforts in the past decade in China. Generally, biodiesel refers to fatty acid methyl ether (FAME) which has a proved effect in reducing diesel emission, particularly PM. However, FAME has a limited cetane number and oxygen content, to study the effects of elevated cetane number and oxygen content on fuel properties, engine combustion and emissions, ethylene glycol monomethyl ether is used to produce a series of new models of biodiesels by transesterification method. The feedstocks are rapeseed oil, soybean oil, peanut oil, palm oil and cottonseed oil. Ether group alcohols used in this study include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether. The molecular structure was proved by FT-IR and NMR analyses. Fuel properties were measured based on the corresponding standards. The developed new model biodiesels have cetane number (CN) over 70 and oxygen content over 17% by mass, which are higher than FAME (50 CN and 11% oxygen). They have the same level of lower heating value as FAME, but have a higher density, which helps to compensate the decrease of engine power. Meanwhile, the engine tests were carried out to investigate the effects of ether ester group on engine combustion and emissions. The test results show that FAME reduced smoke 30% to 50%, while the new model biodiesel fuels reduced engine smoke as high as 80% and have the potential to decrease engine HC, CO and NOx emissions 50% or more
    • …
    corecore