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By using two-dimensional particle-in-cell simulations, we propose a scheme for strong coupling of a petawatt laser with an opening gold cone filled with near-critical-density plasmas. When relevant parameters are properly chosen, most laser energy can be fully deposited inside the cone with only 10% leaving the tip opening. Due to the asymmetric ponderomotive acceleration by the strongly decayed laser pulse, high-energy-density electrons with net laser energy gain are accumulated inside the cone, which then stream out of the tip opening continuously, like a jet. The jet electrons are fully relativistic, with speeds around 0.98 - 0.998 c and densities at 1020/cm3 level. The jet can keep for a long time over 200 fs, which may have diverse applications in practice. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Fallopian tube can transport zygote into the uterine cavity, while inflammation may cause certain influences on the fallopian tube's function. Neutrophils formed extracellular traps (NET) can kill pathogenic microorganisms. This study intends to analyze the role of glucocorticoid in the regulation of NETs sterilization during the fallopian tube staphylococcal infection. MATERIALS AND METHODS: Rat fallopian tube staphylococcal infection model was established. Group A was the control group, group B was the model group, and group C was the dexamethasone intervention group. ELISA was applied to test inflammatory factors, including citrullinated histone H3 (CitH3) and high molecular weight kininogen (HK) content in serum. RT-PCR was performed to test the mRNA expression of glucocorticoid receptor α, β (GR-α, GR-β). Western blot was used to detect the protein levels of GR-α and GR-β. RESULTS: Microscopically, group A showed clear fallopian tube wall and unobstructed lumen. Group B presented obscured tube wall, blocked lumen, and inflammatory cells infiltration. Group C demonstrated unclear tube wall and a few inflammatory cells infiltration. Serum CitH3 level was increased, while HK was down-regulated in group B compared with group A. CitH3 was declined, whereas HK was enhanced in group C compared with group B (p<0.05). The mRNA expression of GR-β was reduced, while GR-α expression was elevated in group C compared with group A and B. Group B showed upregulated GR-β expression and reduced GR-α mRNA and protein expression compared with group A (p<0.05). CONCLUSIONS: Rat fallopian tube Staphylococcus aureus i nfection a ctivates N ETs, e levates CitH3, and decreases HK. Glucocorticoid can inhibit inflammation through down-regulate GR-β and up-regulate GR-α expression. [ABSTRACT FROM AUTHOR]

In a long subcritical density plasma, an ultrashort ultraintense laser pulse can self-organize into a fast but sub-relativistic propagating structure consisting of the modulated laser light and a large number of trapped electrons from the plasma. Upon impact of the structure with a solid foil target placed in the latter, the remaining laser light is reflected, but the dense and hot trapped electrons pass through the foil, together with the impact-generated target-frontsurface electrons to form a dense hot electron cloud at the back of the target suitable for enhancing target normal sheath acceleration of the target-backsurface ions. The accelerated ions are well collimated and of high charge and energy densities, with peak energies a full order of magnitude higher than that from target normal sheath acceleration without the subcritical density plasma. In the latter case, the space-charge field accelerating the ions is limited since they are formed only by the target-frontsurface electrons during the very short instant of laser reflection. [ABSTRACT FROM AUTHOR]

Three-dimensional particle-in-cell simulation is used to investigate radiation-pressure driven acceleration and compression of small solid-density plasma by intense laser pulses. It is found that multiple impacts by presently available short-pulse lasers on a small hemispheric shell target can create a long-living tiny quasineutral monoenergetic plasma bunch of very high energy density. [ABSTRACT FROM AUTHOR]

A simple but comprehensive two-dimensional analytical model for the interaction of a normally incident short intense laser pulse with a solid-density plasma is proposed. Electron cavitation near the target surface by the laser ponderomotive force induces a strong local electrostatic charge-separation field. The cavitation makes possible mode conversion of the laser light into longitudinal electron oscillation at laser frequency, even for initial normal incidence of laser pulse. The intense charge-separation field in the cavity can significantly enhance the laser induced u×B electron oscillation at twice laser frequency to density levels even higher than that of the initial target. [ABSTRACT FROM AUTHOR]