Intensity-modulated radiation therapy (IMRT) quality assurance (QA) is often performed using a 2D device and compares measured and computed fluence maps to determine if a field passes or fails certain dose and position criteria. The effects of a measured deviation to the 3D patient spatial dosimetry and dose volume histogram (DVH) are largely unknown because they cannot be analyzed using commer...

Determination of the mechanisms underlying the growth of tungsten fuzz is an important step towards mitigation of fuzz formation. Nanostructured tungsten was produced on resistively heated tungsten wires in a helicon plasma source (maximum flux of 2.5× 1021 m−2 s−1). Asymmetry in the setup allows for investigation of temperature and flux effects in a single sample. An effort at elucidating the ...

PURPOSE To explore the tissue ablation properties of pulsed 266-nm and 213-nm laser radiation in porcine retina and the potential for 213-nm laser radiation to cut through human trabecular meshwork. METHODS Segments of porcine retinas were used, and localized areas of tissue were exposed to 266-nm or 213-nm laser. Human trabecular meshwork from donor eyes was also ablated using pulsed 213-nm ...

Isotope-selective photodissociation of the volatile complex uranyl hexafluoroacetylacetonate . tetrahydrofuran [UO(2)(hfacac)(2) . THF] has been achieved with both a continuous-wave and a pulsed carbon dioxide laser. The photodissociation was carried out in a low-density molecular beam under collisionless conditions. Transitions of the laser are in resonance with the asymmetric O-U-O stretch of...

BACKGROUND AND OBJECTIVE Based upon the thermal relaxation time of the hair follicle (10-50 ms), most lasers and light devices use relatively long pulse widths for hair removal. This study was conducted to evaluate a shorter pulsed, 0.65 ms Nd:YAG laser for hair removal. METHODS One half of each axilla of six female participants was treated and the other half was monitored as a control. The t...

We present an effective and sensitive method of analyzing the condition of silk following laser cleaning. New silk samples were analysed; two sets were soiled with carbon black before laser cleaning and two sets were left unsoiled. Samples were exposed to laser cleaning at a wavelength of 532 nm and a fluence of 1.5 J/cm2 for 4, 16 and 64 pulses. Two sample sets were also treated at fluence lev...

Results of a phenomenological model to estimate the GRB detection rate by the Fermi Gamma ray Space Telescope are reported. This estimate is based on the BATSE 4B GRB fluence distribution, the mean ratio of fluences measured at 100 MeV – 5 GeV with EGRET and at 20 keV – 2 MeV with BATSE, and the mean EGRET GRB spectrum for the 5 EGRET spark-chamber GRBs. For a 10% fluence ratio and a number spe...

A method of reconstructing three-dimensional, in vivo dose distributions delivered by intensity-modulated radiotherapy (IMRT) is presented. A proof-of-principle experiment is described where an inverse-planned IMRT treatment is delivered to an anthropomorphic phantom. The exact position of the phantom at the time of treatment is measured by acquiring megavoltage CT data with the treatment beam ...

The results of a numerical study on the simulation of pulse amplitude modulated (PAM) fluorometry within dense suspensions of photosynthetic microorganisms are presented. The Monte Carlo method was used to solve the radiative transfer equation in an algae-filled cuvette, taking into account absorption, anisotropic scattering, and fluorescence, as well as Fresnel reflections at interfaces. This ...