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Higher intensity of strong-coupling stimulated Brillouin scattering (SC-SBS) amplification is achieved by supplementary Raman amplification. In the new scheme, a Raman pump laser first amplifies the seed pulse in the homogeneous plasma, then a SC-SBS pump laser continues the amplification in the inhomogeneous plasma in order to suppress the spontaneous instability of pump lasers. The intensity of seed laser gets higher and the duration of seed laser gets shorter than that in the pure SC-SBS scheme with the same incident energy, while the energy conversion effciency is not significantly reduced. We also found that the SC-SBS amplification is seeded by the \pi pulse of Raman amplification. The results obtained from envelope coupling equations, Vlasov simulations and two-dimensional particle-in-cell(PIC) simulations agree with each other. This scheme is a simple and effective way to improve the SC-SBS amplification and is easy to implement in experiments.

In recent years, as a result of the significant development of information and communications technology, people have been paying much attention to automated guided vehicles (AGVs). In the ongoing global coronavirus disease 2019 (COVID-19) pandemic, hospital services have been seriously impacted. In the severe medical situation in hospitals, there is a serious shortage of human resources. This paper presents a novel automated guided vehicle (AGV) for guidance and service. The AGV is comprised of a microcontroller unit (MCU), a power unit, a human sensing unit, a collision warning unit, and a path sensing unit. The motion speed of the AGV and the distance between the AGV and the person being guided are determined by the MCU, the power unit, sensors, and an algorithm. The collision warning unit comprises three ultrasonic sensors and an infrared sensor in the front of the AGV in order to avoid obstacles. The trajectory results of the planned and actual paths are in good agreement. The AGV provides safe and effective guidance for people moving towards their destination. The AGV achieves excellent guidance results and shows great potential for guidance applications in hospitals.

A target composition scheme to optimize the combined proton acceleration regime is presented and verified by two-dimensional particle-in-cell (2D PIC) simulations by using an ultra-intense circularly-polarized (CP) laser pulse irradiating an overdense hydrocarbon (CH) target, instead of a pure hydrogen (H) one. The combined acceleration regime is a two-stage proton acceleration scheme combining the radiation pressure dominated acceleration (RPDA) stage and the laser wakefield acceleration (LWFA) stage sequentially together. With an ultra-intense CP laser pulse irradiating an overdense CH target, followed by an underdense tritium plasma gas, protons with higher energies (from about $20$ GeV up to about $30$ GeV) and lower energy spreads (from about $18\%$ down to about $5\%$ in full-width at half-maximum, or FWHM) are generated, as compared to the use of a pure H target. It is because protons can be more stably pre-accelerated in the first RPDA stage when using CH targets. With the increase of the carbon-to-hydrogen density ratio, the energy spread is lower and the maximum proton energy is higher. It also shows that for the same laser intensity around $10^{22}$ $Wcm^{-2}$, using the CH target will lead to a higher proton energy, as compared to the use of a pure H target. Additionally, proton energy can be further increased by employing a longitudinally negative gradient of a background plasma density., Comment: 16 pages, 8 figures

The anti-Stokes scattering and Stokes scattering in stimulated Brillouin scattering (SBS) cascade have been researched by the Vlasov-Maxwell simulation. In the high-intensity laser-plasmas interaction, the stimulated anti-Stokes Brillouin scattering (SABS) will occur after the second stage SBS rescattering. The mechanism of SABS has been put forward to explain this phenomenon. And the SABS will compete with the SBS rescattering to determine the total SBS reflectivity. Thus, the SBS rescattering including the SABS is an important saturation mechanism of SBS, and should be taken into account in the high-intensity laser-plasmas interaction., Comment: 6 pages, 5 figures

Cytotoxic T-lymphocyte-associated antigen (CTLA-4) is an important downregulator of T-cell activation. In order to analyze the expression and regulation of CTLA-4 on human peripheral T cells, CTLA-4 mRNA and protein expression were determined using analysis by reverse transcription–polymerase chain reaction (RT–PCR) and FACs, respectively. Intracellular CTLA-4 was constitutively expressed in unstimulated CD4+ and CD8+ T cells. Interleukin (IL)-2 induced a dose-dependent increase of both intracellular and surface expression of CTLA-4 (CD152). Most of the CD4+ and CD8+ cells expressing CTLA-4 also expressed CD25. Interferon (IFN)-γ induced the upregulation of CTLA-4 expression via antigen-presenting cells (APC) activation. The CTLA-4delTM mRNA (550 bp) had a shorter half-life than the full length CTLA-4 mRNA and the expression was downregulated upon activation of the cells by treatment with IL-2. Given an inhibitory role of CTLA-4 and CD4+ CD25+ T cells in immune responses, the present findings suggest that IL-2-induced immunosuppression may result from its stimulatory effect of the CTLA-4 expression.

It is shown that well collimated mono-energetic ion beams with a large particle number can be generated in the hole-boring radiation pressure acceleration regime by using an elliptically polarized laser pulse with appropriate theoretically determined laser polarization ratio. Due to the $\bm{J}\times\bm{B}$ effect, the double-layer charge separation region is imbued with hot electrons that prevent ion pileup, thus suppressing the double-layer oscillations. The proposed mechanism is well confirmed by Particle-in-Cell simulations, and after suppressing the longitudinal double-layer oscillations, the ion beams driven by the elliptically polarized lasers own much better energy spectrum than those by circularly polarized lasers., 6 pages, 5 figures, Phys. Plasmas (2013) accepted

Relativistic electromagnetic penetration behavior is reexamined in the relativistic transparency region. The interaction is modeled by the relativistic hydrodynamic equations coupled with the full system of Maxwell equations, which are solved by a fully implicit energy-conserving numerical scheme. For the first time, we have studied the penetration behavior through ultra-short circularly polarized and linearly polarized laser pulses interaction with over-dense plasmas. It is shown that for the ultra-short circularly polarized laser penetration occurs through a soliton like behavior, which is quite consistent with the existing studies. However, we have found that the ultra-short linearly polarized laser penetrates through a breather like behavior, and there is an energy transition mechanism with a frequency $2\omega_0$ between the penetrated breather like structure and the background plasmas. A qualitative interpretation has been given to describe this mechanism of energy exchange., Comment: 6 pages, 6 figures, submitted to Phys. Plasmas

The trans-2-bromotriflate of cycloherane (4) has been solvolyzed at ambient temperatures in HOAc and MeOH containing varying [Br - ] and in the presence of 0.5 M of a scavenger olefin, cyclopentene. The kinetics of solvolysis of 4 have been determined by observing the rate of change in color of an acid/base indicator that instantly responds to the production of HOTf or HBr. The kinetics show that the rate of solvolysis of 4 at constant ionic strength is independent of [Br - ]. The products of solvolysis of 4 under the various conditions have been determined by quantitative GLPC analysis. In the presence of Br - , the products consisted of the trans 1,2-dibromides and bromosolvates of cyclohexane and cyclopentane

The dynamics of the ultra-intense circularly polarized solitons under inhomogeneous plasmas are examined. The interaction is modeled by the Maxwell and relativistic hydrodynamic equations and is solved with fully implicit energy-conserving numerical scheme. It is shown that a propagating weak soliton can be decreased and reflected by increasing plasma background, which is consistent with the existing studies based on hypothesis of weak density response. However it is found that ultra-intense soliton is well trapped and kept still when encountering increasing background. Probably, this founding can be applied for trapping and amplifying high-intensity laser-fields., Comment: 4 pages, 3 figures, submitted to Phys. Plasmas