Rider University

About: Rider University is a education organization based out in Lawrenceville, New Jersey, United States. It is known for research contribution in the topics: Dosimetry & Creativity. The organization has 881 authors who have published 1934 publications receiving 50752 citations.

Assessment of optical CT as a future QA tool for synchrotron x-ray microbeam therapy

Abstract: Synchrotron microbeam radiation therapy (MRT) is an advanced form of radiotherapy for which it is extremely difficult to provide adequate quality assurance. This may delay or limit its clinical uptake, particularly in the paediatric patient populations for whom it could be especially suitable. This study investigates the extent to which new developments in 3D dosimetry using optical computed tomography (CT) can visualise MRT dose distributions, and assesses what further developments are necessary before fully quantitative 3D measurements can be achieved. Two experiments are reported. In the first cylindrical samples of the radiochromic polymer PRESAGE(®) were irradiated with different complex MRT geometries including multiport treatments of collimated 'pencil' beams, interlaced microplanar arrays and a multiport treatment using an anthropomorphic head phantom. Samples were scanned using transmission optical CT. In the second experiment, optical CT measurements of the biologically important peak-to-valley dose ratio (PVDR) were compared with expected values from Monte Carlo simulations. The depth-of-field (DOF) of the optical CT system was characterised using a knife-edge method and the possibility of spatial resolution improvement through deconvolution of a measured point spread function (PSF) was investigated. 3D datasets from the first experiment revealed excellent visualisation of the 50 μm beams and various discrepancies from the planned delivery dose were found. The optical CT PVDR measurements were found to be consistently 30% of the expected Monte Carlo values and deconvolution of the microbeam profiles was found to lead to increased noise. The reason for the underestimation of the PVDR by optical CT was attributed to lack of spatial resolution, supported by the results of the DOF characterisation. Solutions are suggested for the outstanding challenges and the data are shown already to be useful in identifying potential treatment anomalies.

Evaluation and Supervision of Co-Teaching: A Study of Administrator Practices in New Jersey.

Abstract: With the continuing increase of inclusive education in our public school classrooms today, there is a great deal of interest in co-teaching teams. Research indicates that administrative support is ...

Research Article: A phylogenetic analysis of haloarchaea found in a solar saltern

Abstract: In this study, the diversity of the haloarchaea found within a crystallizer pond of a solar saltern located in San Diego, California, USA was examined. Both cultured-based and culture-independent polymerase chain reaction (PCR) 16S ribosomal DNA (rDNA) molecular phylogenetic methodology was employed. Of the eighteen defined genera in the family Halobacteriaceae, three different genera were found to be represented in this study, along with two apparent novel lineages containing only uncultivated representatives. These two novel lineages are most closely related to the genera Halogeometricum and Haloferax. Of the three defined genera represented, Haloarcula, Halobacterium, and Halorubrum, we were able to identify both cultured isolates and DNA from uncultivated members from within these groups. Based on culturing and culture-independent sampling, the predominant members of the haloarchaeal crystallizer community in this particular saltern belonged to the genus Halobacterium. It is also noteworthy that no halophilic bacteria were detected as part of the community in these studies.

On characterizing distributions via linearity of regression for order statistics

Abstract: summary Let X1Xn be a random sample from an absolutely continuous distribution with the corresponding order statistics X1:n≤X2:n≤Xn:n. A complete solution of the problem, posed in 1967 by T. Ferguson, of determining the distribution by linearity of regression of Xk+2:n with respect to Xk:n is given. The only possible distributions are of the exponential, power and Pareto type. A linear regression relation for exponents of order statistics is also considered.

An Analysis of Presidential Preferences in the Distribution of Empowerment Zones and Enterprise Communities

Abstract: Critics regarded the selection of urban empowerment zones and enterprise communities by Secretary Cisneros in 1994 as sympathetic to President Clinton's considerations. However, the secretary countered that cities were chosen based on their ability to revitalize their communities successfully, as outlined in their applications. To determine whether the secretary responded to top-down presidential preferences, data from the complete list of applications is used to test four hypotheses derived from principal—agent theory. The results of the logistic regression models do not validate the significance of the presidential variables (for instance, presidential support score for each city's congressional delegation, marginal districts, and 1992 state vote for President Clinton). Rather, many of the nonpresidential variables (community participation, size of the empowerment zone or enterprise community, and poverty) were significant in supporting the secretary's contention.