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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Application of the cumulative risk model in predicting school readiness in Head Start children

Rodriguez-Escobar, Olga Lydia 15 May 2009 (has links)
This study investigates the degree to which the cumulative risk index predicted school readiness in a Head Start population. In general, the reviewed studies indicated the cumulative risk model was efficacious in predicting adverse developmental outcomes. This study built on this literature by investigating how child, parent, and family risk factors predicted school readiness in Head Start children using two statistical models. Specific aims of this study included identifying 1) to what degree multiple predictors contributed to school readiness and 2) to what degree the cumulative risk index contributed to school readiness. Participants included 176 Head Start children ages 3 to 5 years. Data were analyzed using multivariate regression to determine if the cumulative risk model was a stronger predictor of school readiness than any risk factor in isolation. Hierarchical regression was also utilized to determine if individual risk factors contributed anything above and beyond the sum, the cumulative risk index. Multiple regression analysis revealed that older age and previous enrollment in Head Start predicted higher scores, while low income predicted lower scores, as did taking the test in Spanish. Analysis also revealed that higher scores on the cumulative risk index predicted lower test scores. The analysis revealed that the individual risk factors did not contribute to the model above and beyond the cumulative risk index. Adding the individual risk factors did not account for more variance than using gender, age, and the cumulative risk index as the only predictors. Similarly, the cumulative risk index did not account for more variance than using age and gender as the only predictors. The current study adds empirical support to the continued use of the cumulative risk model in predicting adverse developmental outcomes.
122

The Outcome of Head Injuries: The Saudi Experience

IBRAHIM, E.M., AMMAR, AHMED, CHOWDHARY, U.M., IBRAHIM, M., WAHAB, ABDEL 03 1900 (has links)
No description available.
123

Optimal margins between clinical target volume (CTV) and planning target volume (PTV)

Hjulfors, Emmelie Maria January 2011 (has links)
The purpose of this study was to estimate the CTV-PTV margin required for prostate and head and neck cancer treatments at the radiotherapy departments of Karolinska University Hospital.    Portal image data from patients treated at the radiotherapy departments during the period of 2009-2011 was used to estimate the set-up displacements for each treatment area. By using the acquired images the magnitude of the systematic, i.e. preparatory, and random, i.e. execution, error was determined in the anterior-posterior (AP), superior-inferior (SI) and right-left (RL) direction. The calculated PTV margin is based on the systematic and random errors of the entire patient populations. A total of 40 patients were used for the analysis of prostate treatments and 47 patients for head and neck treatments. The evaluation of the PTV margin was done for three different matching protocols; no matching (skin marker alignment), five day matching and daily matching.      With no image verification in prostate treatments the calculated PTV margin taking both inter- and intrafractional errors into account was 13.6, 9.2 and 7.9 mm in AP, SI, and RL direction respectively. The corresponding PTV margin in head and neck treatments was found to be 6.7, 5.3 and 4.9 mm. Using a five day matching protocol of the bony anatomy showed no considerable reductions in margins for neither prostate nor head and neck treatments. With daily matching of the bony anatomy in prostate treatments the calculated margins was reduced to 8.1, 7.9 and 2.4 mm in the AP, SI and RL direction respectively.  Measurements of the residual deviations of individual cervical vertebrae after daily image verification and correction in head and neck cancer treatments showed that all matching protocols will require larger margins in the lower vertebrae in order to account for the set-up error in the AP direction. The corresponding margins needed using daily matching of the bony anatomy would be 3.9, 5.4 and 6.0 mm for C1, C4 and C5 respectively in the AP direction.    In the absence of daily imaging the currently used PTV margins might be inadequate for covering to movement of the targets. The deviations in the AP direction of the cervical vertebrae in head and neck cancer treatments should be investigated further in order to ensure that the motion of the target is covered and that no risk organs are subjected to harmful dose levels.
124

Study of Impact Sound of Golf Club Head

Lin, Shih-feng 06 September 2010 (has links)
With the popularity of golfing, the marketing of golf clubs has been promoted in recent years. The purpose of this study is to investigate the sound effects of golf impact on different shapes and thicknesses of striking face of the golf club using the finite element method. The researcher found that the vibration model and the resonance frequency of golf club heads. In addition, the researcher used vibration modal analysis to generalize the golf head modes with the distribution of the sound pressure. He also used acoustic transient analysis to check the sound pressure level. Finally, the correlations among the sound pressure, sound pressure level and sound frequency of the golf club head impacts were administered. After all, the study findings provides golf head designers and producers with a reference for designing, revising and producing comfortable and qualified impact sounds of golf club heads.
125

Application of the cumulative risk model in predicting school readiness in Head Start children

Rodriguez-Escobar, Olga Lydia 15 May 2009 (has links)
This study investigates the degree to which the cumulative risk index predicted school readiness in a Head Start population. In general, the reviewed studies indicated the cumulative risk model was efficacious in predicting adverse developmental outcomes. This study built on this literature by investigating how child, parent, and family risk factors predicted school readiness in Head Start children using two statistical models. Specific aims of this study included identifying 1) to what degree multiple predictors contributed to school readiness and 2) to what degree the cumulative risk index contributed to school readiness. Participants included 176 Head Start children ages 3 to 5 years. Data were analyzed using multivariate regression to determine if the cumulative risk model was a stronger predictor of school readiness than any risk factor in isolation. Hierarchical regression was also utilized to determine if individual risk factors contributed anything above and beyond the sum, the cumulative risk index. Multiple regression analysis revealed that older age and previous enrollment in Head Start predicted higher scores, while low income predicted lower scores, as did taking the test in Spanish. Analysis also revealed that higher scores on the cumulative risk index predicted lower test scores. The analysis revealed that the individual risk factors did not contribute to the model above and beyond the cumulative risk index. Adding the individual risk factors did not account for more variance than using gender, age, and the cumulative risk index as the only predictors. Similarly, the cumulative risk index did not account for more variance than using age and gender as the only predictors. The current study adds empirical support to the continued use of the cumulative risk model in predicting adverse developmental outcomes.
126

Is social-emotional development a predictor of school success in Head Start children? A field study

Team, Rachel Marie 02 June 2009 (has links)
Social-emotional development in preschoolers often functions as a gateway into more advanced social and academic behaviors; social-emotional experiences during the preschool years may enhance or diminish a child’s later adjustment and academic outcome. With the current focus on promoting pre-academic skills in preschool programs, the importance of social-emotional development has been left behind. The U.S. Department of Health and Human Services requires initial and follow-up screening of academic readiness skills for the Head Start programs. At the same time, much of the research that relates social-emotional development to academic outcome was completed 20 to 30 years ago. This study examined the relation between academic skills and social-emotional development in the beginning and end of one school year. Approximately 150 children ages 3 to 5 years old were assessed in six Head Start centers in different cities in rural Texas. Each student participated in an academic screening within the first 45 days of school and again at the end of the school year. A parent and teacher also completed a rating scale on each student’s social and emotional skills at the beginning of school. The purpose of this study was to contribute to a better understanding of the impact social-emotional development has on the academic progress for preschool-aged children. The overall goal of this study was to determine the extent to which socialemotional development can predict school readiness in Head Start children. The central hypothesis of this study was that social-emotional development can facilitate or impede children’s academic progress. This project was a prospective, repeated measures, singlesample design. The Head Start children who participated in this study were assessed at the beginning and end of the school year. Gain scores were used to measure the growth in academic skills over one school year and compared to initial social-emotional skill level. Results suggest a relationship between adaptive skills and academic gains in one year is evident in Head Start children, which indicates the importance of continuing to provide services and funding for services that go beyond the basic academic tasks. This study found that social-emotional development influences many vital attributes in a child’s growth, including academic success.
127

The real-time image focusing technique via DVD pickup head

Chiu, Shao-Chun 16 July 2007 (has links)
Due to maturity of experimental technology in recent years, automatic optical inspection (AOI) is used in many industrial applications to replace visual inspection with high-speed and reliable characteristics. Because standard industrial AOI instruments are very expensive, this work introduces a low-cost and high performance AOI instrumentation technique for industrial applications. In this study, we develop an image auto focusing system based on the pickup head of DVD player. We alter the optical path of pickup head and integrate the CCD camera in this system. The idea is to use focus error signal in the linear focus region to estimate the distance between pickup head and object surface. In addition, a capacitance gauging instrument is used to measure the displacement. A PC based control law is then developed by using the PZT to drive the auto focusing system. By setting up such a low-cost system, the experimental results show that the time required for focusing performance is within 0.4s in most cases while the longest focusing time is about 1s. It is hoped that the results of this study can be implemented for real industrial AOI applications.
128

EXPRESSION AND ROLES OF A XENOPUS HEAD-FORMING GENE HOMOLOGUE IN HUMAN CANCER CELL LINES

ZHU, YINGSONG, TSUCHIDA, AKIKO, YAMAMOTO, AKIHITO, FURUKAWA, KEIKO, TAJIMA, ORIE, TOKUDA, NORIYO, AIZAWA, SHINICHI, URANO, TAKESHI, KADOMATSU, KENJI, FURUKAWA, KOICHI 08 1900 (has links)
No description available.
129

Impact Analysis of Various Golf Club Head

Chen, Chau-Tang 09 July 2003 (has links)
Abstract This study aims to investigate the impact effect of varied thickness of the hitting surface and different shapes of the golf club head. The researcher integrated the computer-aided design software Pro/ENGINEER and finite element analysis software LS-DYNA to do the club head design and impact analysis. The researcher had developed five different shapes and eight different thicknesses of hitting surface of the club head model to compare the ball speed and the sweet spot of the hitting surface. He found that ball speed had increased as the hitting surface is enlarged, both laterally and vertically. He also found that thicker center surface and decreasing thickness to the rim of the thickness of the hitting surface is a better design club head. Finally, he made suggestions about the scientific information of the shape and the surface thickness of the golf club head for the designer to develop a suitable club head.
130

A literature review on breastfeeding, head circumference and leg length

Chu, Yiyi 20 August 2012 (has links)
Head circumference and leg length are two important markers for disease outcomes in later life. It has been reported that head circumference values in childhood may be closely related to the brain development and future intellectual functioning. Short leg length in childhood is suggested to have association with an increasing risk of coronary heart disease, diabetes and cancer. Given the potential childhood length and adult disease linkage, it is important to identify the determinants of childhood head circumference and leg length. Breastfeeding is suggested to be a potential postnatal factor that affects head circumference and leg length. However, some studies examining impacts of breastfeeding on leg length and head circumference in childhood reported inconsistent or null findings, indicating that the association between breastfeeding, head circumference and leg length remains controversial. Here we reviewed several studies that investigated the relationship between breastfeeding, head circumference and leg length, and in some but not all studies there was controlling for the effects of other potential early life influences, including parental height, prenatal factors and other postnatal factors on head circumference and leg length. Collectively, the illustrations on these relationships would be useful in investigating the leg length/head circumferencelater disease outcomes associations. / text

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