RESUMO
We identify a class of modal solutions for spatiotemporal optical vortex (STOV) electromagnetic pulses propagating in dispersive media with orbital angular momentum (OAM) orthogonal to propagation. We find that symmetric STOVs in vacuum can carry half-integer intrinsic OAM; for general asymmetric STOVs in a dispersive medium, the OAM is quantized in integer multiples of a parameter that depends on the STOV symmetry and the group velocity dispersion. Our results suggest that STOVs propagating in dispersive media are accompanied by a polaritonlike quasiparticle. The modal theory is in excellent agreement with measurements of free space propagation of STOVs.
RESUMO
This publisher's note contains corrections to Opt. Lett.46, 1013 (2021)OPLEDP0146-959210.1364/OL.417803.
RESUMO
We present a technique for the single-shot measurement of the spatiotemporal (1D space+time) amplitude and phase of an ultrashort laser pulse. The method, transient grating single-shot supercontinuum spectral interferometry (TG-SSSI), is demonstrated by the space-time imaging of short pulses carrying spatiotemporal optical vortices. TG-SSSI is well suited for characterizing ultrashort laser pulses that contain singularities associated with spin/orbital angular momentum or polarization.
RESUMO
We measure the detailed spatiotemporal profiles of femtosecond laser pulses in the infrared wavelength range of λ=2.5-11 µm and the absolute nonlinear response of major air constituents (N2, O2, and Ar) over this range. The spatiotemporal measurements reveal wavelength-dependent pulse front tilt and temporal stretching in the infrared pulses.
Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Sepse/terapia , Infecções Estafilocócicas/terapia , Adolescente , Toxinas Bacterianas , Infecções Comunitárias Adquiridas/terapia , Exotoxinas , Humanos , Leucocidinas , Masculino , Resistência a Meticilina , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismoRESUMO
We postulate that the proteolytic degradation of albumin into fragments could link the rapidity of the shock, rash, and hypocalcaemia associated with meningococcal sepsis. We examined urine of children with meningococcal disease and urine from control children with no sepsis and found albumin fragments of about 45 kDa, 25 kDa, and less than 20 kDa only in the urine of children with meningococcal sepsis and associated purpura. Exogenous or endogenous proteases, or both, may be released in severe meningococcal sepsis and, in association with an inadequate antiprotease response, result in albumin degradation. This may be a contributory factor to the rapid shock, hypocalcaemia, and rash seen in meningococcal sepsis.
