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The interfacial behavior of macromolecules dictates their intermolecular interactions, which can impact the processing and application of polymers for pharmaceutical and synthetic use. Using molecular dynamics simulations, we observe the evolution of a random heteropolymer in the presence of liquid–liquid interfaces. The system of interest forms single-chain nanoparticles through hydrophobic collapse in water, lacking permanent crosslinks and making their morphology mutable in new environments. Complex amphiphilic polymers are shown to be capable of stabilizing high interfacial tension water–hexane interfaces, often unfolding to maximize surface coverage. Despite drastic changes to polymer conformation, monomer presence in the water phase is generally maintained and most changes are due to increased hydrophobic solvent exposure toward the oil phase. These results are then compared to the behavior at the water–graphene interface, where the macromolecules adsorb but do not remodel. The polymer's behavior is shown to depend significantly on both its own amphiphilic character and the deformability of the interface. [ABSTRACT FROM AUTHOR]

The distributed power industry has the characteristics of multiple participants, long business processes, and wide distribution areas, which leads to serious data islands, difficulties in credit transmission, and outstanding transaction risks. Blockchain has technical characteristics such as openness, transparency, traceability, tamper resistance, and decentralization, making it an inevitable trend for its extensive and indepth application in the energy and power industry. The article first analyzes the generation and development of block technology, and then analyzes the current application status of block chain technology in distributed power transactions; then, based on the summary of existing research, it introduces in detail the blockchain-based technology The technical mechanism design of the distributed energy trading scheme analyzes the problems existing in the current application of blockchain in the field of distributed power trading, and proposes targeted development suggestions.

Background: Optogenetics could offer a solution to the current lack of an ambulatory method for the rapid automated cardioversion of atrial fibrillation (AF), but key translational aspects remain to be studied. Objective: To investigate whether optogenetic cardioversion of AF is effective in the aged heart and whether sufficient light penetrates the human atrial wall. Methods: Atria of adult and aged rats were optogenetically modified to express light‐gated ion channels (i.e., red‐activatable channelrhodopsin), followed by AF induction and atrial illumination to determine the effectivity of optogenetic cardioversion. The irradiance level was determined by light transmittance measurements on human atrial tissue. Results: AF could be effectively terminated in the remodeled atria of aged rats (97%, n = 6). Subsequently, ex vivo experiments using human atrial auricles demonstrated that 565‐nm light pulses at an intensity of 25 mW/mm2 achieved the complete penetration of the atrial wall. Applying such irradiation onto the chest of adult rats resulted in transthoracic atrial illumination as evidenced by the optogenetic cardioversion of AF (90%, n = 4). Conclusion: Transthoracic optogenetic cardioversion of AF is effective in the aged rat heart using irradiation levels compatible with human atrial transmural light penetration. [ABSTRACT FROM AUTHOR]

At present, the positioning control of the hydraulic support pushing systems in fully mechanized mining faces uses an electrohydraulic directional valve as the control component, while the current research mainly focuses on servo valves, proportional valves, high−speed on−off valves, and electromagnetic directional valves. At present, the positioning control for electrohydraulic directional valves is only a simple logical control. Therefore, in order to improve the positioning control accuracy of the hydraulic support pushing system, a predictive positioning control strategy based on iterative learning was designed. Firstly, mathematical modeling of the hydraulic support pulling process was carried out, and its state−space equation was established. Secondly, an iterative learning controller with a state observer was designed, in which the iterative learning method was used to predict the control advance in the positioning process, and the state observer was used to estimate the parameters that could not be measured by the system, so as to improve the control accuracy in the broaching process. Then, a SimulationX–Simulink joint simulation model of the position control system of a multi−cylinder pulling hydraulic support was built, and the designed iterative learning controller was compared with the BP neural network controller. Finally, a test platform for the hydraulic support pushing system was built, and the proposed control strategy was experimentally verified. The research results show that the iterative learning control strategy proposed for the electrohydraulic directional valve not only simplifies the design process of the controller but also has higher positioning control accuracy. The single−cylinder positioning control accuracy can be controlled within 10 mm, and the multi−cylinder coordinated positioning control accuracy can be controlled within 15 mm, which meets the accuracy requirements of the site. [ABSTRACT FROM AUTHOR]

Aims Ventricular tachyarrhythmias (VTs) are common in the pathologically remodelled heart. These arrhythmias can be lethal, necessitating acute treatment like electrical cardioversion to restore normal rhythm. Recently, it has been proposed that cardioversion may also be realized via optically controlled generation of bioelectricity by the arrhythmic heart itself through optogenetics and therefore without the need of traumatizing high-voltage shocks. However, crucial mechanistic and translational aspects of this strategy have remained largely unaddressed. Therefore, we investigated optogenetic termination of VTs (i) in the pathologically remodelled heart using an (ii) implantable multi-LED device for (iii) in vivo closed-chest, local illumination. Methods and results In order to mimic a clinically relevant sequence of events, transverse aortic constriction (TAC) was applied to adult male Wistar rats before optogenetic modification. This modification took place 3 weeks later by intravenous delivery of adeno-associated virus vectors encoding red-activatable channelrhodopsin or Citrine for control experiments. At 8–10 weeks after TAC, VTs were induced ex vivo and in vivo , followed by programmed local illumination of the ventricular apex by a custom-made implanted multi-LED device. This resulted in effective and repetitive VT termination in the remodelled adult rat heart after optogenetic modification, leading to sustained restoration of sinus rhythm in the intact animal. Mechanistically, studies on the single cell and tissue level revealed collectively that, despite the cardiac remodelling, there were no significant differences in bioelectricity generation and subsequent transmembrane voltage responses between diseased and control animals, thereby providing insight into the observed robustness of optogenetic VT termination. Conclusion Our results show that implant-based optical cardioversion of VTs is feasible in the pathologically remodelled heart in vivo after local optogenetic targeting because of preserved optical control over bioelectricity generation. These findings add novel mechanistic and translational insight into optical ventricular cardioversion. [ABSTRACT FROM AUTHOR]

There is a little difference between transformer split cooling system and conventional cooling mode, which refers to radiator mounting position and installation modes. Thanks to the specialty of split cooling system, it is complicated to research parameter formulation and model constructing of simulation model. At present, there have been little research about thermal simulation. And it is difficult to identify the accuracy of simulation. Maybe we are expect to carry out deeper simulation research and trial comparisons. The paper has conducted three-time temperature-rise test in terms of transformed 10 kV oil-filled transformer. There have set up transformer three dimensional flow of split cooling system-solid-thermal simulation model based on simulation trials. We adopt finite volume methods to solve region temperature field of transformer. And we have obtained winding heat spot of different locations in terms of split cooling. Though the analysis of comparisons, we have concluded that the center height of radiator of miniature oil immersed transformer improves 2 meters. And the hot-spot temperature declines to 8K. Horizontal distance between radiator and transformer shrinks 3.5m, while the hot-spot temperature declines 4K. After the comparisons of experimental data, we have acquired the results of theoretical calculation and simulation model. Besides, we have gained important data that relative error is within +5%, which has verified accuracy of simulation model and engineering practicability. The paper has analyzed the cooling efficiency of split cooling mode effectively. It provides technical support for the building of split cooling mode. It provides relative data for the cooling structure optimization of large-scale oil immersed transformer and orientation of hot-spot temperature measurement of optical fiber. [ABSTRACT FROM AUTHOR]