Accuracy of SRS dose delivery using the TomoTherapy Hi-Art System

Purpose: To quantify the accuracy and precision of both target positioning and dose delivery for intracranial radiosurgery delivered with the TomoTherapy Hi-Art System using a non-invasive immobilization device. Methods: Techniques developed by Vinci et al (2007) were refined for the measurement of dose distributions in each principal plane using a CIRS head phantom. Pieces of Gafchromic EBT2 film were cut and digitized using a template developed by Vinci et al (2007). A plan was created for a 2 cm diameter x 2 cm long cylindrical target in the TomoTherapy treatment planning system (TPS) version 3.2.1. Intentional misalignments of 5 mm in each of the principal directions were applied to the phantom prior to treatment delivery. The MVCT feature of the TomoTherapy Hi-Art system was used to correct for these misalignments, and then the treatment was delivered. Measured dose distributions (film) were registered to the calculated dose distributions (TPS planar dose) and compared. Results: Alignment errors (displacement between the midpoints of the measured and calculated 70% dose points; mean ± standard deviation) were -0.15 ± 0.47 mm (range: -1.97 to 0.8 mm), -0.36 ± 0.56 mm (range: -1.25 to 0.63 mm), and -0.67 ± 0.93 mm (range: -3.04 to 0.90 mm) in the superior-inferior, anterior-posterior, and lateral directions, respectively. Positional errors of the 80% dose points in millimeters were 1.28 ± 0.91 (range: -0.09 to 3.62), -0.02 ± 0.96 (range: -2.24 to 1.72), -0.04 ± 0.62 (range: -1.24 to 1.25), 0.64 ± 0.52 (range: -0.35 to 1.55), 0.30 ± 0.52 (range: -1.57 to 1.28), and 0.60 ± 0.46 (range: -0.26 to 2.39) for the right, left, posterior, anterior, inferior, and superior directions, respectively. Conclusions: Using a non-invasive immobilization device, 1.98 mm dose voxel size, and manual lateral couch positioning, the spatial accuracy of dose delivery with the TomoTherapy Hi•Art System was not within 1 mm as hypothesized

A comparative study of contrasting structural styles in the range-front region of the northeastern Arctic National Wildlife Refuge, northeastern Brooks Range, Alaska

Thesis (Ph.D.) University of Alaska Fairbanks, 1991The range front of the northeastern Brooks Range in the Arctic National Wildlife Refuge (ANWR) is defined by anticlinoria cored by a 'basement' complex of weakly metamorphosed sedimentary, volcanic and intrusive rocks. These anticlinoria are interpreted to reflect horses in a northward-propagating regional duplex between a floor thrust at depth in the 'basement' complex and a roof thrust near the base of the cover sequence. Lateral variations in the geometry of these range-front anticlinoria reflect changes in lithology and deformational style of both the 'basement' and its cover. Two distinct structural geometries are displayed along the range front of northeastern ANWR. To the east, the large range-front anticlinorium is interpreted to reflect multiple horses of Cenozoic age within the stratified, slightly metamorphosed sedimentary and volcanic rocks of the pre-Mississippian 'basement'. During Cenozoic thrusting, these mechanically heterogeneous rocks deformed primarily via thrusting and related folding with minor penetrative strain. The Mississippian and younger cover sequence shortened via both thrust duplication and detachment folding above a detachment in the Mississippian Kayak Shale. In contrast, to the west the pre-Mississippian rocks consist primarily of the mechanically homogeneous Devonian Okpilak batholith. The batholith was transported northward during Cenozoic thrusting and now forms a major topographic and structural high near the range front. The batholith probably shortened during thrusting as a homogeneous mass via penetrative strain. Because the Kayak Shale is thin to absent in the vicinity of the batholith, Mississippian and younger rocks remained attached to the batholith and shortened via penetrative strain and minor imbrication. These two range-front areas form the central portion of two regional transects through northeastern ANWR. General area-balanced models for both transects suggest that the amount of total shortening is governed by the structural topography and the geometry of the basal detachment surface. While the structural topography of northeastern ANWR is reasonably well-constrained, the geometry of the basal detachment is not. Given a range in reasonable basal detachment geometries, shortening in both transects ranges from 16% to 61%. Detailed balanced cross sections based on subsurface and surface geologic data yield 46-48% shortening for both transects

Neurometric Profiling of Autism Spectrum Disorder using The Brief Neurometric Battery: A Novel Eeg Based Task

Autism spectrum disorder is a pervasive developmental disorder characterized by heterogeneous deficits in social communication and interaction, as well as repetitive behaviors and restricted interests. Due to the dramatic increase in prevalence, a major theme in contemporary research has been the identification of biomarkers for ASD that can shed light on etiological factors, facilitate diagnosis and serve as markers for tracking the efficacy of behavioral and pharmacological treatments. Electroencephalography (EEG) metrics, such as event-related potentials (ERPs), resting state oscillatory activity (OA), and resting state complexity (multiscale entropy), are well-suited for the measurement of such biomarkers. Due to the complexity and heterogeneity of ASD symptoms, it is important that research aiming to use EEG to identify biomarkers of autism and other neurodevelopmental disorders focus on determining the relationships between electrophysiological neurometrics and clinical presentation. The objective of the present research was two-fold; 1) synthesize a profile of ERP and OA metrics, collected during a novel Brief Neurometric Battery, that differentiates between youth with ASD and controls, and 2) determine if a relatively novel analysis of resting state EEG complexity (MSE) can be used to differentiate between ASD and controls. Through a two study approach, this research was able to synthesize a multivariate profile that classified youth with and without ASD at an accuracy rate comparable to that of the gold standard methods (ADI-R/ADOS) and identify an additional neurometric, multiscale entropy, that can accurately differentiate between youth with ASD and controls

The influence of early questions on learning from text

In this research we explored the use of short-answer questions to improve learning from chapter-like texts (3395 words). Experiment 1 investigated the influence of pre-questions on recall from a text passage when tested a week later; two question sets were counterbalanced within the experimental group. Participants with pre-questions scored higher both overall (d = 3.6, 95%CI [2.4, 4.8]) and on novel questions (d = 2.0 [1.6, 2.4]). In Experiment 2, questions were made available immediately after studying the text either alongside the text, open-book, or closed-book with the opportunity to check answers, or not at all with additional study time. Learning was tested after a week. Although the immediate test scores were substantially higher for open- than closed-book tests, week-delayed performance on the same items was much worse for open-book tests and was moderately improved for closed-book tests. For seen questions, closed-book tests led to better delayed recall than did open-book tests, d = 0.7 [0.02, 1.5]. For novel questions, observed differences were small; ds = .2 [-0.6, 0.9] for both comparisons

A Comparison of Human Energy Fields Among Children, Youth, Adults, & Dahn Masters

While concepts and investigations of human energy fields have been developed for centuries, there has been little systematic work comparing the fields of children, adolescents, and adults. In addition, general fields have had little comparison between average adults and those participating in an intense practice that may affect the field. Using the GDV machine, this research compared small groups of children, adolescents, average adults, and Dahn Hak Masters on measures of 20 basic aspects of the human energy fields, including the seven chakras. Differences were found in seven of the 13 field parameters as well as all seven measures of the chakras. The largest fields occurred with the Dahn Masters while children had the highest entropy (communication with the environment). Difference on chakras showed children to be the most open while adults were the most shut down. The means for Dahn Masters were more consistent with those for children and adolescents than other adults, suggesting that changes in the field with age may be different when people do extensive work that affects the field. Further research is required to verify these preliminary results and test additional questions raised by this study

A COMPARISON OF HUMAN ENERGY FIELDS AMONG CHILDREN, YOUTH, ADULTS & DAHN MASTERS

While concepts and investigations of human energy fields have been developed for centuries, there has been little systematic work comparing the fields of children, adolescents, and adults. In addition, general fields have had little comparison between average adults and those participating in an intense practice that may affect the field. Using the GDV machine, this research compared small groups of children, adolescents, average adults, and Dahn Hak Masters on measures of 20 basic aspects of the human energy fields, including the seven chakras. Differences were found in seven of the 13 field parameters as well as all seven measures of the chakras. The largest fields occurred with the Dahn Masters while children had the highest entropy (communication with the environment). Difference on chakras showed children to be the most open while adults were the most shut down. The means for Dahn Masters were more consistent with those for children and adolescents than other adults, suggesting that changes in the field with age may be different when people do extensive work that affects the field. Further research is required to verify these preliminary results and test additional questions raised by this study

Deconstructing Teresa O’Brien: A Role Play For Domestic Violence Clinics

In this article, we will present and examine the role play that we have used with our students. We will provide the actual text of the role play, with an explanatory narrative about how we integrated the role play into our classroom component. We will outline the reading assignments and pre-class preparation that we require. Finally, we will suggest ways that this role play can be adapted for clinical programs in other jurisdictions or in countries with other legal systems