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This paper introduces the characteristics of mountain rack railway trains and their starting status in China. The particularities of the signal system in the safety control of the rack railway trains are analyzed. The control strategy of the signal system in the process of "gear in" and "gear out" of the mountain rack railway trains is described emphatically. It also analyzes and discusses the calculation of safety protection curves of signal system when a rack railway train switches between the gear rail area and the wheel rail area. The methods of stationary-train switching and dynamic switching are proposed. [ABSTRACT FROM AUTHOR]

The traditional aqueous film-forming foam extinguishing agent (AFFF) plays an important role in fighting liquid fires, but its environmental hazard are also increasingly prominent. The key component of conventional AFFF is fluorocarbon surfactant containing perfluorinated C8 segment, which is one of the most refractory organic pollutants in the world. In this paper, a perfluorinated branched short-chain alkyl side chain fluorocarbon anionic surfactant with high surface activity and simple synthesis route was prepared. The surface activity and aggregation behavior of the mixed solution of fluorocarbon and hydrocarbon surfactants were studied by surface tension meter and transmission electron microscope (TEM). When the mixture ratio of fluorocarbon and hydrocarbon surfactant reached 1:10, the addition of cetyltrimethylammonium bromide (CTAB) had little effect on the interfacial adsorption, but could significantly reduce the critical micelle concentration (CMC) of fluorocarbon surfactant. Meanwhile, three kinds of environment-friendly AFFF formulations (F-1, F-2, F-3) were designed with the mixed system of different hydrocarbon surfactants and this fluorocarbon anionic surfactant as foaming agents. The foam properties revealed the F-2 possessed excellent foam performance, the initial foam height h0 was 120 mm, and the 25% drainage time was 240 s, extinguishing time was 30 s, burn-back time was 760 s. [ABSTRACT FROM AUTHOR]

Background: Tumor treating fields (TTFields) is an FDA‐approved adjuvant therapy for glioblastoma. The distribution of an applied electric field has been shown to be governed by distinct tissue structures and electrical conductivity. Of all the tissues the skull plays a significant role in modifying the distribution of the electric field due to its large impedance. In this study, we studied how remodeling of the skull would affect the therapeutic outcome of TTFields, using a computational approach. Methods: Head models were created from the head template ICBM152 and five realistic head models. The electric field distribution was simulated using the default TTFields array layout. To study the impact of the skull on the electric field, we compared three cases, namely, intact skull, defective skull, and insulating process, wherein a thin electrical insulating layer was added between the transducer and the hydrogel. The electric field strength and heating power were calculated using the FEM (finite element method). Results: Removing the skull flap increased the average field strength at the tumor site, without increasing the field strength of "brain". The ATVs of the supratentorial tumors were enhanced significantly. Meanwhile, the heating power of the gels increased, especially those overlapping the skull defect site. Insulation lightly decreased the electric field strength and significantly decreased the heating power in deep tumor models. Conclusion: Our simulation results showed that a skull defect was beneficial for superficial tumors but had an adverse effect on deep tumors. Skull removal should be considered as an optional approach in future TTFields therapy to enhance its efficacy. An insulation process could be used as a joint option to reduce the thermogenic effect of skull defect. If excessive increase in heating power is observed in certain patients, insulating material could be used to mitigate overheating without sacrificing the therapeutic effect of TTFields. [ABSTRACT FROM AUTHOR]

NAMPT is an attractive target in cancer therapy and numerous NAMPT inhibitors have been developed. However, the clinical activities of NAMPT inhibitors have displayed disappointing results in clinical trials for their dose-limiting toxicities. In this study, reactive oxygen species (ROS)-responsive prodrugs of a NAMPT inhibitor FK866 were designed and synthesized. A short synthesis method was developed to shield the activity of FK866 through a quaternary ammonium connection. Two prodrugs, with boronic acid as a responsive group to ROS, were prepared and one of the prodrugs 122-066 also contained a fluorescence carrier. Both of the prodrugs released the active compound by the treatment of H2O2,, and the biological evaluation showed that they exhibited a higher potency in cells with high levels of ROS. Moreover, prodrug 122-066 had the ability to release FK866 and simultaneously induce the fluorescence activation under the stimulation of H2O2. This method has the potential to improve the therapeutic window of NAMPT inhibitors. [ABSTRACT FROM AUTHOR]

Human‐made concrete structures require cutting‐edge inspection tools to ensure the quality of the construction to meet the applicable building codes and to maintain the sustainability of the aging infrastructure. This paper introduces a wall‐climbing robot for metric concrete inspection that can reach difficult‐to‐access locations with a close‐up view for visual data collection and real‐time flaws detection and localization. The wall‐climbing robot is able to detect concrete surface flaws (i.e., cracks and spalls) and produce a defect‐highlighted 3D model with extracted location clues and metric measurements. The system encompasses four modules, including a data collection module to capture RGB‐D frames and inertial measurement unit data, a visual–inertial navigation system module to generate pose‐coupled keyframes, a deep neural network module (namely InspectionNet) to classify each pixel into three classes (background, crack, and spall), and a semantic reconstruction module to integrate per‐frame measurement into a global volumetric model with defects highlighted. We found that commercial RGB‐D camera output depth is noisy with holes, and a Gussian‐Bilateral filter for depth completion is introduced to inpaint the depth image. The method achieves the state‐of‐the‐art depth completion accuracy even with large holes. Based on the semantic mesh, we introduce a coherent defect metric evaluation approach to compute the metric measurement of crack and spall area (e.g., length, width, area, and depth). Field experiments on a concrete bridge demonstrate that our wall‐climbing robot is able to operate on a rough surface and can cross over shallow gaps. The robot is capable to detect and measure surface flaws under low illuminated environments and texture‐less environments. Besides the robot system, we create the first publicly accessible concrete structure spalls and cracks data set that includes 820 labeled images and over 10,000 field‐collected images and release it to the research community. [ABSTRACT FROM AUTHOR]