Vero4DRT is an innovative image-guided radiotherapy system employing a C-band X-ray head with gimbal mechanics. The purposes of this study were to propose specific MC models of the linac head and multileaf collimator (MLC) for the Vero4DRT and to verify their accuracy. For a 6 MV photon beam delivered by the Vero4DRT, a simulation code was implemented using EGSnrc. The linac head model and the ...

The resolution of multileaf collimators (MLCs) is limited by their finite leaf width. A commercial package (HD-270) uses 3D couch translation and leaf adjustments to emulate smaller leaf widths. In this paper, we report on the commissioning of this feature using software testing, dial gauge measurements, and film dosimetry. We also identify a variety of limitations: software bugs and truncation...

This paper studies a learning approach to geometric shaping (GS) for concatenated two-level multi-level codes (MLC). Unlike standard bit-interleaved coded modulation (BICM), the proposed MLC protects only least reliable bits (LRBs) by an inner code, and thereby efficiently reduces complexity associated with soft-decision (SD) decoding compared BICM without performance degradation. We propose ne...

Stereotactic body radiation therapy (SBRT) using recently introduced multileaf collimators (MLC) is preferred over circular collimators in the treatment of localized prostate cancer. The objective of this study was to assess the clinical usefulness of MLCs in prostate SBRT by comparing the effectiveness of treatment plans using fixed collimators, variable collimators, and MLCs and by ensuring d...

Urinary bladder dysfunction caused by the alteration of detrusor smooth muscle (DSM) is one of the complications of diabetes. It is well established that smooth muscle contractility is regulated by an elevation of cytosolic Ca(2+) via myosin light chain (MLC) phosphorylation. However, recent studies have shown the modulation of MLC phosphorylation without a rise in Ca(2+) in smooth muscle and t...

ID: 7461 Title: Multileaf Collimator (MLC) for Field Matching Photon field matching at the beam isocenter using independent jaws is the method of choice in many radiation treatments that require abutted fields. This study evaluated the suitability of using Multileaf Collimator (MLC) for such matching. The study employed a treatment planning system to model the field matching and the modeling wa...

Contractile activity in smooth muscle cells is regulated by phosphorylation-dephosphorylation of the 20,000-Da light chain of myosin. In an attempt to better understand the localization in muscle of the enzymes which catalyze the phosphorylation-dephosphorylation process, we measured the binding constants of turkey gizzard smooth muscle myosin light chain (MLC) kinase and smooth muscle phosphat...

Classification for high-dimensional remotely sensed data generally requires a large set of data samples and enormous processing time, particularly for hyperspectral image data. In this paper, we present a fast two-stage classification method composed of a band selection (BS) algorithm with feature extraction/selection (FSE) followed by a recursive maximum likelihood classifier (MLC). The first ...