A general design of caging-group free photoactivatable fluorophores for live-cell nanoscopy

The controlled switching of fluorophores between non-fluorescent and fluorescent states is central to every superresolution fluorescence microscopy (nanoscopy) technique, and the exploration of radically new switching mechanisms remains critical to boosting the performance of established, as well as emerging superresolution methods. Photoactivatable dyes offer significant improvements to many of these techniques, but often rely on photolabile protecting groups that limit their applications. Here we describe a general method to transform 3,6-diaminoxanthones into caging-group free photoactivatable fluorophores. These photoactivatable xanthones (PaX) assemble rapidly and cleanly into highly fluorescent, photo- and chemically stable pyronine dyes upon irradiation with light. The strategy is extendable to carbon- and silicon-bridged xanthone analogs, yielding a new family of photoactivatable labels spanning much of the visible spectrum. Our results demonstrate the versatility and utility of PaX dyes in fixed and live-cell fluorescence microscopy, and both coordinate-targeted stimulated emission depletion (STED) and coordinate-stochastic single-molecule localization superresolution microscopy (SMLM).

Controlled Switching Diffusions Under Ambiguity: The Average Criterion

This paper concerns controlled switching diffusions. In particular, we consider that the drift coefficient of the diffusion process depends on an unknown (and possibly nonobservable) parameter. For giving solution to our control problem, we formulate it as a game against nature, where the ambiguity is represented by nature that chooses values of the unknown parameter through actions so playing the role as an opposite player of the controller. Our objective is to give conditions to characterize the ergodic optimality and guarantee the existence of optiaml policies for the central controller. Finally, we provide two examples to illustrate our results.

Residual flux impact in controlled switching of HVDC converter transformer

Converter transformers are an interface point of HVDC frameworks and are basic hardware from activity and reliability view point. Converter transformers are turned off intentionally under planned support and un-deliberately during fault conditions. Random energization of HVDC Converter transformer delivers high inrush currents due to core saturation asymmetries and endanger equipment health. In this paper, charging approach has been proposed. By utilizing point on wave exchanging for moderation of charging drifters during charging of 888 MVA 400/325 kV Converter Transformer of ±800 kV HVDC Sub-station. The proposed procedure has been applied on HVAC electrical Circuit Breaker furnished with Pre-Insertion Resistor considering diverse degree of residual flux. Performance of proposed philosophy has been affirmed by field tests and reproduction in PSCAD programming package and is found very viable. Near investigation is done in this paper and shows that with the use of proposed system, the switching transient during stimulation and field tests of coupled three phase converter transformers is decreased to worthy level.

Research Based on Modeling and Simulation of the Transient Regime in Controlled Switching with High Power Switches

This paper addresses one of the current areas of interest in electrical engineering, which is controlled switching of high voltage circuit breakers. During their operation, the problem of controlled switching of high voltage circuit breakers in commutation regimes was studied. Several types of switching were analyzed, considered representative of the transient regime, depending on the type of load, on the defect that may occur on the power supply lines, as well as depending on the position of this defect (near or far). The study carried out in the paper includes simulations of the controlled connection/disconnection operations in a transient regime, assuming the existence of different kinds of defects. To perform the study and simulations in the transient regime, a model, implemented in Matlab, was used for a time interval located around the origin of the time axis. The study included the dependence of the SF6 circuit breaker switching process on the following parameters: the DC voltage supply, ambient temperature and oil pressure in the circuit breaker actuator. The validity of the theory presented in this paper, in addition to being validated by simulations, is proven by the fact that the protection system currently in use at the power station of an 800 MW power plant, at the 400 kV power line, is based on the principles presented in this paper. The theory presented in the paper has been implemented in industry for nearly two years, and the results confirm that the theory presented in the paper is fully applicable in high voltage power stations.

IMPROVING THE EFFICIENCY OF DISTRIBUTION NETWORK CONTROL UNDER THE CONDITIONS OF APPLICATION OF DISTRIBUTED SOURCES GENERATION OF ELECTRICAL ENERGY AND MEANS OF ITS ACCUMULATION

New technological solutions have been proposed that allow effective reduction of electrical energy losses in distribution networks with local generation sources and storage units due to the possibility of dynamic control of the network configuration. The conditions for the rational use of remotely controlled switching devices have been substantiated and an algorithm for controlling their operation has been developed. The possibility of using power electronics devices is demonstrated and an approach to their operation is proposed in order to create optimal flows of active and reactive power in the distribution network circuit to minimize energy losses. References 9, figures 3.

Study of Voice Communication System Based on FreeSWITCH

With the rapid development of communication technology, modern communication technology has been widely penetrated into modern national defense, science and technology, people's life and other fields, and has become a means to provide high-quality and seamless information communication between people and machines. With the rapid development of computer technology and the Internet, the traditional program-controlled switching technology has come to an end, and the soft-switch network based on IP technology and packet switching has gradually replaced the program-controlled switching network based on circuit switching and become the mainstream of today's communication network world. The rapid development of VOIP telephony reduces the cost of domestic and international long-distance telephony, benefiting consumers. Digital mobile communication expands channel capacity, improves service quality and promotes the rapid development of this industry. Based on the secondary development of the open source FreeSWITCH software, this paper develops a VOIP voice system based on IP technology to meet different user needs intelligently [1].