The effect of background knowledge on young children's comprehension of explicit and implicit information

Bibliography: leaves 15-16Supported in part by the National Institute of Educatio

A two-sling mechanism of hyolaryngeal elevation in the pharyngeal phase of swallowing

Thesis (Ph.D.)--Boston UniversityThe pharyngeal phase of swallowing is a complex function that transfers a bolus from the oral cavity through the hypopharynx into the esophagus. A critical event in this process is the elevation of the hyolaryngeal complex, which opens the upper esophageal sphincter and relocates the airway away from an oncoming bolus. The suprahyoid group of muscles (mylohyoid, geniohyoid, digastric, and stylohyoid) and thyrohyoid are thought to underlie this function. The role of a deeper posterior sling of muscles that is comprised of stylopharyngeus, salpingopharyngeus and palatopharyngeus has not been determined. This project aims to investigate a hypothesized two-sling mechanism for hyolaryngeal elevation in the pharyngeal phase of swallowing. The thesis begins with background information of the functional anatomy thought to underlie hyolaryngeal elevation followed by an outline of studies that validate the structure, function, and clinical relevance of the two-sling mechanism. A cadaver model is first used to calculate potential force vectors of the muscular slings. The function of the two-sling apparatus is then investigated in vivo by using muscle functional MRI to evaluate muscles active in swallowing and dynamic MRI to perform kinematic analysis on key anatomical landmarks that represent attachment sites of the two-sling mechanism. Finally, the clinical significance of the two-sling mechanism is demonstrated by comparing spatial and temporal measurements collected from fluoroscopic imaging studies of patients with normal swallowing ability and swallowing difficulty

EuAgxAl11−x with the BaCd11-Type Structure: Phase Width, Coloring, and Electronic Structure

The EuAgxAl11−x (loading composition, x ≈ 3−8) ternary system was experimentally and theoretically investigated. According to powder X-ray diffraction, phases adopting the BaCd11-type structure (space group I41/amd, Z = 4) were obtained for a narrow composition range, i.e., x ≈ 5−6. Single-crystal X-ray crystallography showed that Ag and Al atoms share 4b, 8d, and 32i sites and that 4b site distinctly prefers Ag to Al. Eu is divalent in these phases, which was supported by both magnetometry and unit-cell dimensional analysis. Comparison with other isostructural RE (rare earth)−Ag−Al compounds showed that the BaCd11-type structure is stable specifically at the valence electron concentrations (vec) of 2.1−2.3 e− per atom. A Mulliken population analysis was performed with Extended Hückel calculations, the result of which explained the observed site preferences of the Ag and Al atoms. TB-LMTO-ASA calculations were used to study the relative energies of various models established according to crystallography and the coloring problem was included by maximizing the number of Ag−Al contacts. The calculated density of states (DOS) and crystal orbital Hamiltonian population (COHP) curves explain the stability of the BaCd11-type structure at specifically vec ≈ 2.1−2.3 e− per atom in RE−Ag−Al ternary compounds

Extracting quantum dynamics from genetic learning algorithms through principal control analysis

Genetic learning algorithms are widely used to control ultrafast optical pulse shapes for photo-induced quantum control of atoms and molecules. An unresolved issue is how to use the solutions found by these algorithms to learn about the system's quantum dynamics. We propose a simple method based on covariance analysis of the control space, which can reveal the degrees of freedom in the effective control Hamiltonian. We have applied this technique to stimulated Raman scattering in liquid methanol. A simple model of two-mode stimulated Raman scattering is consistent with the results.Comment: 4 pages, 5 figures. Presented at coherent control Ringberg conference 200

Determining position and orientation of a 3-wheel robot on a pipe using an accelerometer

Accurate positioning of robots on pipes is a challenge in automated industrial inspection. It is typically achieved using expensive and cumbersome external measurement equipment. This paper presents an Inverse Model method for determining the orientation angle (α ) and circumferential position angle (ω) of a 3 point of contact robot on a pipe where measurements are taken from a 3-axis accelerometer sensor. The advantage of this system is that it provides absolute positional measurements using only a robot mounted sensor. Two methods are presented which follow an analytical approximation to correct the estimated values. First, a correction factor found though a parametric study between the robot geometry and a given pipe radius, followed by an optimization solution which calculates the desired angles based on the system configuration, robot geometry and the output of a 3-axis accelerometer. The method is experimentally validated using photogrammetry measurements from a Vicon T160 positioning system to record the position of a three point of contact test rig in relation to a test pipe in a global reference frame. An accelerometer is attached to the 3 point of contact test rig which is placed at different orientation (α ) and circumferential position (ω) angles. This work uses a new method of processing data from an accelerometer sensor to obtain the α and ω angles. The experimental results show a maximum error of 3.40° in α and 4.17° in ω , where the ω circumferential positional error corresponds to ±18mm for the test pipe radius of 253mm

Gravity optimised particle filter for hand tracking

This paper presents a gravity optimised particle filter (GOPF) where the magnitude of the gravitational force for every particle is proportional to its weight. GOPF attracts nearby particles and replicates new particles as if moving the particles towards the peak of the likelihood distribution, improving the sampling efficiency. GOPF is incorporated into a technique for hand features tracking. A fast approach to hand features detection and labelling using convexity defects is also presented. Experimental results show that GOPF outperforms the standard particle filter and its variants, as well as state-of-the-art CamShift guided particle filter using a significantly reduced number of particles

Implementation of geriatric assessment in oncology settings: A systematic realist review

Older adults with cancer are more likely to have worse clinical outcomes than their younger counterparts, and shared decision-making can be difficult, due to both complexity from adverse ageing and under-representation in clinical trials. Geriatric assessment (GA) has been increasingly recognised as a predictive and prehabilitative tool for older adults with cancer. However, GA has been notoriously difficult to implement in oncological settings due to workforce, economic, logistical, and practical barriers. We aimed to review the heterogenous literature on implementation of GA in oncology settings to understand the different implementation context configurations of GA and the mechanisms they trigger to enable successful implementation. A systematic realist review was undertaken in two stages: i) systematic searches with structured data extraction combined with iterative key stakeholder consultations to develop programme theories for implementing GA in oncology settings; ii) synthesis to refine programme theories. Medline, Embase, PsycInfo, Cochrane Library, CINAHL, Web of Science, Scopus, ASSIA, Epistemonikos, JBI Database of Systematic Reviews and Implementation Reports, DARE and Health Technology Assessment were searched. Four programme theories were developed from 53 included articles and 20 key stakeholder consultations addressing the major barriers of GA implementation in oncology practice: time (leveraging non-specialists), funding (creating favourable health economics), practicalities (establishing the use of GA in cancer care), and managing limited resources. We demonstrate that a whole system approach is required to improve the implementation of GA in cancer settings. This review will help inform policy decisions regarding implementation of GA and provide a basis for further implementation research