RESUMEN

We analyze the spatiotemporal intensity of pulses with durations of 20 fs and shorter and a carrier wavelength of 810 nm at the paraxial focal plane of an achromatic doublet lens. The incident pulse is well-collimated, and we use the Seidel aberration theory for thin lenses to evaluate the phase change due to the aberrations of the lens. In a set of cemented thin lenses with the stop at the lens, there is only spherical aberration, coma, astigmatism and field curvature, whereas the distortion aberration in the phase front is zero. We analyze the effect of these aberrations in the focusing of ultrashort pulses for homogenous illumination. We will show that the temporal spreading introduced by these aberrations in pulses shorter than 20 fs at 810 nm is very small but the spatial spreading is not, which reduces the intensity of the pulse considerably.

RESUMEN

We analyze the spatiotemporal intensity of Gaussian temporal envelope pulses with initial durations of 200 fs and a carrier wavelength of 810 nm at the paraxial focal plane of an achromatic doublet lens for a well-collimated incoming pulse beam by using the Seidel aberration theory for thin lenses with the stop at the lens. We analyze the effect of these aberrations in the focusing of ultrashort pulses for Gaussian illumination and present experimental results for 200 fs pulses focused by a near-IR achromatic doublet.

RESUMEN

We report 3 patients with fibrous solitary tumor of meningeal location where we described the histological study, as well as evolution after the surgical treatment. The described patients presented ages of 37, 52 and 65 years, after the resection has not appeared an objective sign of recurrence in any case after 4, 6 and 7 years of follow-up respectively. Checking the literature the tumor is indistinguishable clinical and radiolocally of the typical meningioma, doing necessary the use of inmunohistochemistry to do the differential diagnosis, where positiveness for CD34 and the negativeness for EMA define the fibrous solitary tumor. It is about a benign tumor, where total removing is the principal factor in prognosis, nevertheless there are cases of local recurrences and long-distance metastasis. We can find all these characteristics in the showed cases of the present article, having the uncertainty of its local or systemic relapse ability in the future.

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RESUMEN

Presentamos 3 pacientes con tumor fibroso solitario de localización meníngea donde describimos el estudio histológico, así como la evolución después del tratamiento quirúrgico. Los pacientes descritos tenían edades de 37, 52 y 65 años y tras la resección total no se ha objetivado signo de recidiva en ningún caso después de 4, 6 y 7 años de seguimiento respectivamente. Revisando la literatura se trata de un tumor indistinguible clínica y radiológicamente del meningioma típico, haciendo necesario el uso de pruebas inmunohistoquímicas para realizar el diagnóstico diferencial, donde la positividad para el CD34 y la negatividad para el EMA definen al tumor fibroso solitario. Se trata de un tumor benigno, en el que la resección total es el principal factor pronóstico; no obstante, se han descrito casos de recidivas locales y metástasis a distancia. Todas estas características las encontramos en los casos presentados en el presente trabajo, quedando la incertidumbre de su capacidad de recidiva local o sistémica en el futuro

We report 3 patients with fibrous solitary tumor of meningeal location where we described the histological study, as well as evolution after the surgical treatment.The described patients presented ages of 37, 52 and 65years, after the resection has not appeared an objective sign of recurrence in any case after 4, 6 and 7 years of follow-up respectively. Checking the literature the tumor is indistinguishable clinical and radiolocally of the typical meningioma, doing necessary the use of inmunohistochemistry todo the differential diagnosis, where positiveness forCD34 and the negativeness for EMA define the fibrous solitary tumor. It is about a benign tumor, where total removing is the principal factor in prognosis, nevertheless there are cases of local recurrences and long-distance metastasis. We can find all these characteristics in the showed cases of the present article, having the uncertainty of its local or systemic relapse ability in the future

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A new method, to our knowledge, allowing one to simulate correlated random processes is suggested. Structure (or correlation) functions of the processes under simulation are assumed to be given. The method is based on the generation of random wave vectors that allows one to simulate processes for a wide class of structure functions. The validity of the method proposed is illustrated by simulations of the turbulence-induced log-amplitude and phase distortions.

RESUMEN

Argon laser exposures in vitro were done on human aortas. The laser energy applied on a fresh aorta section (A) was from 100mw to 1000mw. A second aorta section (B), formalin fixed, was irradiated under saline solution by a fiberoptic system. Laser energy was from 400mw to 720mw. The time exposures were all different in both sections. A and B histologic findings of thermal damage were similar Three zones of tissue injury were observed: I) crater because of tissue vaporization; II) coagulative necrosis surrounding it; and III) multiple vacuoles in the adjacent tissue produced by acoustic or shock injury. Tissue damage was related directly with total energy delivered: less than or equal to 500mw showed inner vascular wall necrosis, and at greater than or equal to 720mw it was perforated. Atherosclerotic tissue was more resistant to laser thermal injury than normal tissue. We could not find time relation with thermal damage. This preliminary information is an early step for the possible use of Argon laser on cardiovascular area.

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