The purpose of this study was to validate the newly designed acrylic phantom for routine dosimetric purpose in radiotherapy. The phantom can be used to evaluate and compare the calculated dose and measured dose using film and gel dosimetric methods. In this study, a doughnut-shaped planning target volume (8.54 cm3) and inner organ at risk (0.353 cm3) were delineated for an IMRT test plan using ...

The paper begins with the problem of a firm subject to random productivity shocks drawn from a particular distribution. We are concerned with the case whereby the distribution of the shocks changes without the knowledge of the firm. Over time the firm learns about the nature and extent of the change in the distribution of the shock and adjusts, incurring adjustment costs in the process. The lon...

This work illustrates a procedure to assess the overall accuracy associated with Gamma Knife treatment planning using plugging. The main role of source plugging or blocking is to create dose falloff in the junction between a target and a critical structure. We report the use of MAGAT gel dosimeter for verification of an experimental treatment plan based on plugging. The polymer gel contained in...

This article addresses the linguistic evidence from which details about Philippine "negritos" can be inferred. This evidence comes from the naming practices of both negrito and non-negrito peoples, from which it can be inferred that many negrito groups have maintained a unique identity distinct from other groups since the dispersal of Malayo-Polynesian languages. Other names, such as Dupaningan...

Background:  In this study a series of basic dosimetric properties of a low-density (LD) gel dosimeter are investigated. The dose response is studied regarding to linearity, sensitivity, dose-rate and energy dependence as well as lung tissue equivalence. Materials and Methods: The LD gel was made by mixing the polymer gel with expanded polystyrene spheres. Energy dependence was studied...

How does the informational role of interest groups interact with institutions in the political control of the bureaucracy? In 1992, Banks and Weingast argued that bureaucrats hold an informational advantage vis-à-vis political principals concerning variables with direct policy relevance, and that an agency can exploit this information if it chooses to do so because politicians and bureaucrats i...