the term ultra short is not clearly defined in ultrashort-segment hirschsprung’s disease. the limited extent of the ultrashort-segment hirschsprung’s disease allows for treatment with extended sphincteromyectomy. in anal sphincter achalasia, anal sphincter dilatation under general anesthesia may be sufficient to treat the condition; in cases with persistent constipation, sphincteromyectomy is i...

Recent research demonstrates that white matter of the brain contains not only long T2 components, but a minority of ultrashort T2* components. Adiabatic inversion recovery prepared dual echo ultrashort echo time (IR-dUTE) sequences can be used to selectively image the ultrashort T2* components in white matter of the brain using a clinical whole body scanner. The T2*s of the ultrashort T2* compo...

Relatively little experimental and theoretical data exist on the retinal hazards of ultrashort laser pulses operating in the visible and near infrared spectral regions. Because of potential nonlinear effects that can occur from high-peak irradiance, ultrashort laser pulses propagate from the cornea to the retina, we have developed four projects within our Ultrashort Pulse Effects program. First...

Energetic ions and ultrashort X-rays were generated by an intense ultrashort laser interacting with a copper target. Fast ions up to 3 MeV were observed with CR-39 nuclear track detector sheets when 7 TW laser was used. Cu ∼ Cu ions with the energy from 50 keV to 220 keV were detected with a Thomson parabola detector in the case of the laser power of 2.5 TW. Time-resolved X-ray diffraction was ...

A variety of nonlinear effects such as self – phase modulation (SPM) lead to spectral broadening of optical pulses. In the case of intense ultrashort pulses, when SPM is accompanied by other nonlinear processes such as stimulated Raman scattering and four-wave mixing, it leads to an extreme spectral broadening referred to as supercontinuum. In this paper, we demonstrate the effects of various n...

The development of ultrashort pulse laser technology will have a strong impact on the advancement of laser machining. Ultrashort laser pulses can reduce the heat-affected zone and the shock-affected zone, resulting in much cleaner cuts, and therefore higher precision. Also, ultrashort laser pulses have shown remarkable promise for processing transparent materials such as glass, fused silica, an...

We present results on the occurrence of ultrashort terahertz harmonic generation (THG) driven by a millimeter nonlinear chirped few-cycle laser pulse in a symmetric double quantum well. By solving the effective nonlinear Bloch equations, THG with a generic plateau and cutoff can be produced. The time–frequency characteristic of the ultrashort terahertz harmonic spectrum is analyzed in detail by...

Ultrashort single-walled carbon nanotubes, i.e. with length below ~30 nm, display length-dependent physical, chemical and biological properties that are attractive for the development of novel nanodevices and nanomaterials. Whether fundamental or applicative, such developments require that ultrashort nanotube lengths can be routinely and reliably characterized with high statistical data for hig...

AIM To determine cumulative success rate (CSR) of short and ultrashort implants in the posterior maxilla restored with single crowns. PATIENTS AND METHODS We performed a retrospective study in 65 patients with 139 implants. 46 were ultrashort and 93 short. Implants were placed with a staged approach and restored with single crowns. Success rate, clinical and radiographic outcomes, and crown-t...

To compare oocyte quality and clinical outcome after an ultrashort or a modified suppression gonadotrophin-releasing hormone agonist (GnRHa) protocol for ovarian stimulation in intracytoplasmic sperm injection (ICSI) cycles, we conducted a prospective randomized study of 60 consecutive couples with severe male infertility admitted for their first in-vitro fertilization (IVF) and ICSI attempt. M...