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The present work is devoted to establishing the ultrashort pulse laser ablation generalized thermoelastic model with spatio-temporal nonlocal effect and investigating the transient responses of the process of silicon ablated by the picosecond pulse laser. The research is divided into three cases. 1) The solid silicon before the target surface melting is studied, and the transient responses of the final state of this case are taken as the initial conditions of the Case Two. 2) The liquid silicon after the target surface melting is researched, and the heat flux taken away by vaporization is considered in the boundary condition. 3) The solid silicon after the target surface melting is discussed, and the moving solid-liquid interface is regarded as the coordinate origin. The coupled governing equations containing spatial nonlocal parameter, time delay factor, and kernel function are established and solved by the Laplace transform together with its numerical inversion. The melting time and depth of target are emphatically discussed. The temperature, displacement and stress with different laser intensity, spatial nonlocal parameter, time delay factor, kernel function as well as time are obtained and illustrated graphically. [ABSTRACT FROM AUTHOR]

Corneal myofibroblasts play a crucial role in the process of corneal scarring. Potassium has been documented to reduce skin scar tissue formation. Herein, we investigated the ability of potassium to prevent corneal fibrosis in cell culture and in vivo. Corneal fibroblasts (CFs) were isolated from the corneal limbus and treated with TGF-β1 to transform into corneal myofibroblasts. Corneal myofibroblast markers were detected by quantitative real-time PCR, Western blot, and immunofluorescence. The contractive functions of corneal myofibroblast were evaluated by the scratch assay and the collagen gel contraction assay. RNA sequencing in corneal fibroblasts was performed to explore the mechanisms underlying hyperosmolar potassium treatment. GO and KEGG analysis were performed to explore the underlying mechanism by hyperosmolar potassium treatment. The ATP detection assay assessed the level of cell metabolism. KCl eye drops four times per day were administered to mice models of corneal injury to evaluate the ability to prevent corneal scar formation. Corneal opacity area was evaluated by Image J software. Treatment with hyperosmolar potassium could suppress corneal myofibroblast transformation and collagen I synthesis induced by TGF-β1 in cell culture. Hyperosmolar potassium could inhibit wound healing and gel contraction in CFs. RNA sequencing results suggested that genes involved in the metabolic pathway were downregulated after KCl treatment. ATP levels were significantly decreased in the KCl group compared with the control group. Hyperosmolar potassium could prevent corneal myofibroblast transformation after corneal injury and corneal scar formation in mice. Potassium can suppress corneal myofibroblast transformation and collagen I protein synthesis. Moreover, given that KCl eye drops can prevent corneal scar formation, it has been suggested to have huge prospects as a novel treatment approach during clinical practice. [ABSTRACT FROM AUTHOR]

Steady-state cross-regulation is a critical issue for dual-output dc-dc converters. The effect of leakage inductance on steady-state cross-regulation of dual-output LLC resonant converter is analysed in this Letter. It is revealed that a proportional relation between leakage inductance and load resistance of dual-output LLC resonant converter ensures zero steady-state cross-regulation. Furthermore, the variations of steady-state cross-regulation with regards to leakage inductance and load resistance are concluded. Finally, experimental results are provided to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This letter proposes a novel control technique called as voltage mode-capacitor current ripple hybrid control (VCHC) strategy for single-inductor dual-output (SIDO) buck converter in inductor current continue conduction mode (CCM). The proposed strategy aims to reduce the cross regulation which is a key technical drawback of SIDO CCM buck converter. A small-signal model is also developed to investigate the frequency-domain responses of the proposed converter. The bode plots based on the small-signal model show that the proposed control strategy significantly reduces the cross regulation and improves transient performance compared with the one with voltage mode-inductor current ripple hybrid control. Finally, simulation and experiment results verify the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

A microcapsule containing a silane coupling agent was prepared by spray drying. The optimal encapsulating condition was determined by employing a response surface methodology with a central composite design. The effect of emulsion’s solid content and oil concentration, inlet air temperature, and atomizer speed on properties of microcapsule were investigated. The resulting microcapsule containing silane coupling agent and possessing an unbroken surface and a good shape under optimized conditions exhibited an encapsulation efficiency of 82.7%, average size of 21.3 µm, and moisture content of 0.93%. The experimental results agree well with the model prediction, with a relative error below 5.0%. [ABSTRACT FROM PUBLISHER]