We describe here the first case of osteitis caused by Candida haemulonii in a young immunocompetent patient. This patient presented a history of severe peripheral vascular disease associated with a ...lack of hygienic conditions as the only risk factors for such an uncommon infection. Clinical signs and histological examination allowed us to determine that it was a C. haemulonii infection and not colonization. The outcome was favourable with oral voriconazole therapy and surgical revascularization. An environmental cause of such infections is most probable, as C. haemulonii has previously been isolated from different non-human sources. Identification methods, results obtained with three in vitro antifungal susceptibility methods and clinical features are reported.
We present measurements of the temporal decay rate of one-dimensional (1D), linear Langmuir waves excited by an ultrashort laser pulse. Langmuir waves with relative amplitudes of approximately 6% ...were driven by 1.7J, 50fs laser pulses in hydrogen and deuterium plasmas of density n_{e0}=8.4×10^{17}cm^{-3}. The wakefield lifetimes were measured to be τ_{wf}^{H_{2}}=(9±2) ps and τ_{wf}^{D_{2}}=(16±8) ps, respectively, for hydrogen and deuterium. The experimental results were found to be in good agreement with 2D particle-in-cell simulations. In addition to being of fundamental interest, these results are particularly relevant to the development of laser wakefield accelerators and wakefield acceleration schemes using multiple pulses, such as multipulse laser wakefield accelerators.
A gamma-ray source with an intense component around the giant dipole resonance for photonuclear absorption has been obtained via bremsstrahlung of electron bunches driven by a 10-TW tabletop laser. ...3D particle-in-cell simulation proves the achievement of a nonlinear regime leading to efficient acceleration of several sequential electron bunches per each laser pulse. The rate of the gamma-ray yield in the giant dipole resonance region (8<E{gamma}<17.5 MeV) was measured, through the radio activation of a gold sample, to be 4 x 10;{8} photons per joule of laser energy. This novel all-optical, compact, and efficient electron-gamma source is suitable for photonuclear studies and medical uses.
Objectives
The aim of the study was to describe a new evolutionary form of visceral leishmaniasis observed in immunocompromised patients.
Methods
We carried out long‐term clinical and biological ...follow‐up of 10 HIV‐1/Leishmania‐coinfected patients presenting numerous secondary visceral leishmaniasis episodes despite treatment, with the follow‐up time ranging from 0.5 to 10 years.
Results
Analysis of polymerase chain reaction (PCR) and blood culture results demonstrated continuous multiplication and circulation of parasites despite treatment, both during asymptomatic periods and during secondary visceral leishmaniasis episodes. This condition may be termed ‘chronic’ because of the presence of relapses over a period of several years and ‘active’ because of the continuous blood circulation of the parasite.
Conclusion
We wish to define ‘active chronic visceral leishmaniasis’ as a novel nosological entity observed in HIV‐1/Leishmania‐coinfected patients.
A novel mechanism for injection, emittance selection, and postacceleration for laser wakefield electron acceleration is identified and described. It is shown that a laser prepulse can create an ...ionized plasma filament through multiphoton ionization and this heats the electrons and ions, driving an ellipsoidal blast-wave aligned with the laser-axis. The subsequent high-intensity laser-pulse generates a plasma wakefield which, on entering the leading edge of the blast-wave structure, encounters a sharp reduction in electron density, causing density down-ramp electron injection. The injected electrons are accelerated to∼2MeVwithin the blast-wave. After the main laser-pulse has propagated past the blast-wave, it drives a secondary wakefield within the homogenous background plasma. On exiting the blast-wave structure, the preaccelerated electrons encounter these secondary wakefields, are retrapped, and accelerated to higher energies. Due to the longitudinal extent of the blast-wave, only those electrons with small transverse velocity are retrapped, leading to the potential for the generation of electron bunches with reduced transverse size and emittance.
We demonstrate resonant excitation of a plasma wave by a train of short laser pulses guided in a preformed plasma channel, for parameters relevant to a plasma-modulated plasma accelerator (P-MoPA). ...We show experimentally that a train of N≈10 short pulses, of total energy ∼1J, can be guided through 110mm long plasma channels with on-axis densities in the range 10^{17}–10^{18}cm^{−3}. The spectrum of the transmitted train is found to be strongly red shifted when the plasma period is tuned to the intratrain pulse spacing. Numerical simulations are found to be in excellent agreement with the measurements and indicate that the resonantly excited plasma waves have an amplitude in the range 3–10GVm^{−1}, corresponding to an accelerator stage energy gain of order 1GeV.
The interaction of relativistically intense lasers with opaque targets represents a highly non-linear, multi-dimensional parameter space. This limits the utility of sequential 1D scanning of ...experimental parameters for the optimization of secondary radiation, although to-date this has been the accepted methodology due to low data acquisition rates. High repetition-rate (HRR) lasers augmented by machine learning present a valuable opportunity for efficient source optimization. Here, an automated, HRR-compatible system produced high-fidelity parameter scans, revealing the influence of laser intensity on target pre-heating and proton generation. A closed-loop Bayesian optimization of maximum proton energy, through control of the laser wavefront and target position, produced proton beams with equivalent maximum energy to manually optimized laser pulses but using only 60% of the laser energy. This demonstration of automated optimization of laser-driven proton beams is a crucial step towards deeper physical insight and the construction of future radiation sources.
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