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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.
41

Assessing the behavioral aspects of executive functioning across the lifespan: review of rating scales and psychometric derivation of a screener for young adults

Duggan, Emily Clare 03 September 2014 (has links)
Executive functioning skills are paramount to our ability to purposefully and successfully mediate our actions within our day-to-day environment. Dysfunction of the executive system can result in a multitude of behavioral manifestations in all stages of life. Increasing evidence supports the use of rating scales to obtain a more comprehensive and ecologically valid understanding of an individual’s executive functioning. The current thesis involves two articles examining the use of behavioral rating scales in the assessment of executive functions. Study 1: In response to a recent proliferation of executive functions rating scales, this article reviews and discusses currently available scales for the assessment of executive functions across the lifespan. Study 2: This study derived an executive functions screener from the Behavioral Assessment System for Children (BASC-2-SRP-COL) for use in young adults and evaluated it against a well-known executive function rating scale (the Behavior Rating Inventory of Executive Function-Adult Version). / Graduate / 0622 / 0632 / eduggan@uvic.ca
42

Cellular lifespan based pharmacodynamic analysis of erythropoiesis

Freise, Kevin Jay 01 July 2009 (has links)
The disposition of cells whose mechanism of death is related to the age of the cell cannot be appropriately represented by pharmacodynamic (PD) models where the elimination rate is related to the number of cells. In cells with age-related death their disposition is determined by their lifespan. Thus in these cells PD models of cellular response must incorporate a lifespan component. Previous cellular lifespan PD models assumed that the lifespan of cells is predetermined and does not vary over time. However, in many instances these assumptions are inappropriate and thus extensions to the existing models are needed. An important application of these time variant PD models is determining the erythropoiesis rate, since the lifespan of reticulocytes and mature erythrocytes are known to change over time under specific conditions. The objectives us this work were to develop a general time variant lifespan-based PD model of cellular response and to use the model to determine the dynamic changes over time in both the erythrocyte lifespan and erythropoiesis rate under a variety of complex conditions. An initial time variant cellular lifespan model was formulated assuming no variability in lifespans and used to determine the dynamic changes in both the reticulocyte lifespan and erythropoiesis rate in sheep. Subsequently, the time variant model was extended to account for a distribution of cellular lifespans, which resulted in better capturing the physiology of sheep erythrocyte maturation. The model was then further extended to account for the effect of changes in the environment on cell lifespans and used to determine the effect of chemotherapy administration on sheep erythrocytes. In order to conduct studies on erythropoiesis in premature very low birth weight (VLBW) infants the ability to accurately measure erythrocytes and hemoglobin from clinically collected excess blood was validated. Then an in depth analysis of the relationship between erythropoietin, erythrocytes, and hemoglobin was conducted in a clinical study of premature VLBW infants that accounted for the dynamic hematological conditions experienced by these subjects. This analysis indicated that a nearly 4-fold increase in erythropoiesis could be achieved with only a modest increase in plasma erythropoietin concentrations.
43

Examining Physical Activity Infrastructure Importance across the Lifespan

Walker, Joseph T., Walker, Laura, Walker, Joseph T., Dotterweich, Andy R., Gould, J. 01 January 2013 (has links)
No description available.
44

Hodnocení hodu míčkem u žáků 1. stupně ZŠ pomocí dvou vybraných metodik / The evaluation of overarm throw in elementary school children using two selected methodologies

Filip, Ondřej January 2020 (has links)
Title: The evaluation of overarm throw in elementary school children using two selected methodologies Work objectives: The diploma thesis aim is to determine and assess the level of overarm throw technique in 1st and 2nd grade of elementary school using two different evaluation methods meda by Haywood and Getchell (2014) and Haibach, Reid and Collier (2011). The results of the evaluation of overarm throw by the methodology of Haywood and Getchell (2014) will then be compared with the results of the evaluation of the diploma theses created by Maryšková (2007) and Králová (2014). The sub-objective is to create an overview of the evaluation of product and process of overarm throw and to determine whether the methodology of evaluating the overarm throw according to Haibachová, Reid and Collier (2011) can be applied to children of elementary school in Czech conditions. Methodology: The study involved 70 probands, of which 35 boys and 35 girls, attending 1st and 2nd grade of elementary school. Monitoring the movement level of the overarm throw was realized by the method of participatory observation. Probands conducted three attempts in the defined area. Two digital video cameras were used for recording for more detailed analysis of motion using selected methodologies. The camera was statically placed to...
45

Don’t forget to remember – Prospective memory across the lifespan

Aberle, Ingo 28 October 2009 (has links)
Prospective memory refers to the ability to remember to carry out delayed intentions, more precisely, to remember to initiate and execute an intended action at some point in the future. The development and progression of prospective memory across the lifespan is still heavily under debate. Only few studies have so far investigated prospective memory development in childhood, revealing an inconsistent pattern. In adulthood, studies in the laboratory and naturalistic studies showed paradoxical results with age deficits in the laboratory and age benefits in naturalistic tasks. Up to now, no conceptual model has been suggested to guide research on prospective memory development across the lifespan. Thus, the present work examined the effect of central factors from the multiprocess framework (McDaniel & Einstein, 2000) on the development of prospective memory in four different age-groups: pre-schoolers, school-age children, young and old adults. The first study explored the role of task motivation in age differences in prospective memory performance across the pre-school age-range. No main effect of age or motivation in prospective memory performance was found, yet a significant interaction, indicating that for younger children motivation or task importance may help allocating the available resources to the task elements of interest. Evidence from the second study indicated that 9-10 year old school children outperform 6-7 year old school children on a measure of prospective memory, and that retrieval-based factors (ongoing task absorption, cue salience, cue focality) systematically influenced performance. Of particular importance for possible developmental mechanisms was the finding of an age x cue focality interaction, suggesting that age effects may be modulated by cue focality. The third study examined the effect of task setting in a laboratory procedure and the effect of motivation in a naturalistic procedure on prospective memory performance in young and older adults. Results from the laboratory prospective memory procedure revealed significant age-related decline for irregular tasks but not for regular and focal tasks. In addition, in the naturalistic procedure, the age benefit was eliminated when young adults were motivated by incentives. Results from the present work indicated that already pre-school age children were able to remember to perform intended actions and this ability increased across school-age. In adulthood, the results revealed a decline with age on a pure performance level. Yet, older adults may be able to compensate for basic cognitive impairments if task conditions reduce the need for controlled attention. Furthermore, the present work suggest, that factors of the multiprocess framework may indeed affect age-differences in prospective memory performance throughout the lifespan, as cue focality and task importance were related to prospective memory development in children and adults. Thus, the multiprocess approach might serve as foundation for a lifespan theory of the development of prospective memory.
46

Identifying the pathophysiology of depression and its permeability across the lifespan

Kaylin E Hill (9167717) 29 July 2020 (has links)
<div> <div> <div> <p>Major depressive disorder (MDD) and risk for its development are characterized by reduced reactivity and flexibility to environmental demands. Frontal alpha asymmetry (FAA), heart rate variability (HRV), and salivary cortisol reactivity are each well-established indicators of regulation across neural, autonomic, and hypothalamic-pituitary-adrenal (HPA) physiological systems, respectively. Growing literature suggests that each of these processes is dysregulated in individuals with a history of MDD. However, patterns of dysregulation across these physiological systems and relative MDD risk are unknown. Moreover, these physiological regulatory patterns may extent beyond markers of MDD risk in adulthood to also capture the transmission of risk for MDD from parent to offspring. The following series of five studies investigated the pathophysiology of MDD and the permeability of risk across the lifespan. First, the pattern of dysregulation across physiological indices—representing neural, autonomic, and HPA functioning—in adults was examined with regard to depressive symptoms. Second, the associations amongst infant FAA, HRV, and cortisol reactivity and maternal depressive symptoms were assessed as potential early markers of depression risk. Third, mother-infant associations across physiological indices were investigated to assess direct intergenerational transmission of depression risk. Studies 4 and 5 further investigated pathophysiological functioning in mothers and infants within the context of comorbid anxiety and current depressive symptomatology versus lifetime MDD illness. Mothers and their 12-month-old infants (n = 35 dyads) completed resting- state and stressor tasks to assess regulatory patterns across neural, autonomic, and HPA systems, associations with MDD, and intergenerational transmission. In adults, results suggest that lifetime history of MDD is significantly associated with blunted cortisol reactivity; FAA and high- frequency HRV also demonstrated the same direction of associations. In infants, results demonstrated that maternal depressive symptoms, particularly current symptoms, relate to blunted physiological regulation in infants specifically for FAA and HRV indices. For mothers and infants, there was support for the direct intergenerational transmission of FAA and HRV indices. These intergenerational associations did not fully account for intergenerational risk of depression, as maternal physiological regulation and maternal depression were found to each significantly predict infant regulation as simultaneous predictors. Accounting for comorbid anxiety and examining current symptoms versus lifetime illness were essential to investigating associations amongst physiological functioning and depression. These patterns in conjunction with the literature suggest a developmental model to MDD pathophysiology that encompasses multiple theoretical frameworks. Future research is necessary to clarify regulatory patterns across physiological systems within individuals and across time with regard to MDD risk, onset, and course.</p></div></div></div>
47

Utveckling av testmaskin för teknik i skor / Development of test machine for wearable technology

Kuyumcuoglu, Gabriel, Lagerström, Sebastian January 2016 (has links)
RECCO AB är ett företag som utvecklar räddningssystem för lavinolyckor. Systemet fungerar genom en RFID tag (reflektor) och en detektor. Detektorn känner av reflektorn som sitter på jackan, hjälmen, skon eller pjäxan upp till 200 meters avstånd eller 30 meter genom snön. Detektorn används av erfaren lavinräddningspersonal. RECCO ska implementera reflektorer i vandringsskor för att söka efter människor som är i skogen och uppe i bergen. Syftet med examensarbetet är att utveckla en skotestmaskin som ska kunna testa livslängden på reflektorn. Bakgrundsundersökningen genomfördes genom en informationssökning om biomekanik i ben och fot, olika benrörelser som kan påverka skon, olika typer av vandringsskor och olika skotestmaskiner som finns ute på marknaden idag. Genomförandet av projektet inleddes genom ett test för att undersöka hur stora krafterna är som påverkar reflektorn i skon. Testet genomfördes med en tryckkänslig sensor och en Arduino UNO. Den maximala kraften på reflektorn blev 7.1 N. Därefter gjordes en brainstorming som resulterades i sju olika koncept. Koncepten vägdes emot varandra med hjälp av en PUGH matris, som resulterade i att ett koncept valdes att gå vidare med. Analysen av konceptet genomfördes med Solidworks, Matlab och ADAMS. Med SolidWorks gjordes detaljerade ritningar och ett montage av modellen. Med Matlab gjordes beräkningar på lagerhus, glidlager, kulbussning och motor. ADAMS användes för att simulera rörelsen och för att verifiera Matlab-beräkningarna. Resultatet av slutprodukten blev lyckat. Maskinens rörelse och de påverkande krafterna på reflektorn efterliknar testet som genomfördes i början av projektet. Eventuella förbättringar som kan utföras är inköp av en starkare motor för att uppnå en mer konstant hastighet eller ett svänghjul för att minska påfrestningarna på motorn. För vidare arbete på slutprodukten kan RECCO programmera en strömbrytare som stänger av motorn vid uppnått antal cykler. / RECCO is a company that develops rescue system for avalanche accidents. The system works by a RFID tag (reflector) and a detector. The detector senses the reflector that is attached to jackets, helmets, shoes and ski boots up to 200 meters or 30 meters through the snow. The detector is used by experienced avalanche rescue groups. RECCO will implement reflectors in hiking shoes to search for people who are in the woods and in the mountains. The purpose of this master theses is to develop a shoe test machine to be able to test the service life of the reflector. The background study was performed by an information search about the biomechanics of the leg and foot, different leg movements that may affect the shoe, different types of hiking shoes and several shoe test machines available on the market today. The implementation of the project began with a test to examine how large the forces are on the reflector acting in the shoe. The test was conducted by a pressure sensitive sensor connected to an Arduino UNO. The maximum force on the reflector was 7.1 N. This was followed by a brainstorming session that resulting in seven different concepts. The concepts were then evaluated against each other using a PUGH matrix, which resulted in a concept for further development. The analysis was conducted using SolidWorks, Matlab, and ADAMS. Detailed drawings and assembly of the model were made using SolidWorks. The calculations were made on bearing housings, plain bearings, linear ball bearing and the motor using Matlab. ADAMS was used to simulate the movement and to verify the Matlab calculations. The result of the final concept was succeeded. The machine's movement and the influencing forces on the reflector mimic the performed test that was made at the beginning of the project. Improvements that can be done is to change to a more powerful motor to achieve a more constant speed or a flywheel to reduce the strain on the motor. For further work RECCO can program a switch that turns off the motor when the number of cycles are achieved.
48

Vliv kvality artikulačních UHMWPE vložek na životnost kloubních náhrad / The influence of the quality of articulation UHMWPE inserts on the lifetime of joint replacements

Fulín, Petr January 2016 (has links)
This thesis focuses on the introduction with the problems of high molecular weight polyethylene (UHMWPE) in orthopedics in the first part. It discusses the history, properties and processes that lead to the failure of UHMWPE joint replacement components. The experimental part validates the hypotheses expressed. It acquaints readers with the experimental verification of the effect of different types of sterilization on the oxidative stability of laboratory prepared samples and explanted UHMWPE joint replacement components using methods of infrared microscopy, electron spin resonance, mechanical tests and tests of microhardness. Other experimental measurements on a large set of explanted components of hip and knee total joint replacements validates the hypothesis that the amount of oxidative damage affects the lifespan of joint replacements. The third part of the experimental study maps the degree of oxidative damage in different places of the hip and knee joint replacements. In the final part we experimentally demonstrate the fact that the rate of oxidative damage has an effect on supramolecular structure of the UHMWPE. From the above experiments are concluded clearly defined recommendations for clinical practice, which should lead to extend the lifespan of total joints replacements in orthopaedics....
49

Chinese Canadian young adults' experiences of parental monitoring

So, Vivien Wing Yin 26 July 2021 (has links)
This dissertation focuses on the family experiences of Chinese Canadian young adults raised in immigrant families. Drawing on contextual and transactional theories of development and parenting, this dissertation investigates Chinese young adults’ experiences and interpretations of parental monitoring and their links to youth well-being and family functioning. There is a relative lack of knowledge about the nature and interpretations of Chinese immigrant parenting in young adulthood and a lack of consensus regarding the conceptualization of parental monitoring both in adolescence and in young adulthood in mainstream and immigrant populations. This research achieved several objectives in a series of three papers. In Paper 1, I uncovered the range of Chinese Canadian young adults’ perceived parental monitoring behaviours and motivations for such behaviours in a qualitative study using freelisting methodology. In Paper 2, I sought to understand the construct of monitoring in this demographic by creating a multidimensional measure of parental monitoring of Chinese Canadian young adults. In Paper 3, I explored how young adults’ unmet expectations for parental monitoring related to well-being using polynomial regressions and response surface analyses. This research addressed several gaps in the literature by extending the study of parental monitoring to young adulthood, adding to the scant literature on parenting of Chinese immigrant young adults, distinguishing between mothers’ and fathers’ parenting, and moving toward a more complete conceptualization of parental monitoring. / Graduate / 2022-07-14
50

Ketone Bodies Mimic the Life Span Extending Properties of Caloric Restriction

Veech, Richard L., Bradshaw, Patrick C., Clarke, Kieran, Curtis, William, Pawlosky, Robert, King, M. Todd 01 May 2017 (has links)
The extension of life span by caloric restriction has been studied across species from yeast and Caenorhabditis elegans to primates. No generally accepted theory has been proposed to explain these observations. Here, we propose that the life span extension produced by caloric restriction can be duplicated by the metabolic changes induced by ketosis. From nematodes to mice, extension of life span results from decreased signaling through the insulin/insulin-like growth factor receptor signaling (IIS) pathway. Decreased IIS diminishes phosphatidylinositol (3,4,5) triphosphate (PIP3) production, leading to reduced PI3K and AKT kinase activity and decreased forkhead box O transcription factor (FOXO) phosphorylation, allowing FOXO proteins to remain in the nucleus. In the nucleus, FOXO proteins increase the transcription of genes encoding antioxidant enzymes, including superoxide dismutase 2, catalase, glutathione peroxidase, and hundreds of other genes. An effective method for combating free radical damage occurs through the metabolism of ketone bodies, ketosis being the characteristic physiological change brought about by caloric restriction from fruit flies to primates. A dietary ketone ester also decreases circulating glucose and insulin leading to decreased IIS. The ketone body, d-β-hydroxybutyrate (d-βHB), is a natural inhibitor of class I and IIa histone deacetylases that repress transcription of the FOXO3a gene. Therefore, ketosis results in transcription of the enzymes of the antioxidant pathways. In addition, the metabolism of ketone bodies results in a more negative redox potential of the NADP antioxidant system, which is a terminal destructor of oxygen free radicals. Addition of d-βHB to cultures of C. elegans extends life span. We hypothesize that increasing the levels of ketone bodies will also extend the life span of humans and that calorie restriction extends life span at least in part through increasing the levels of ketone bodies. An exogenous ketone ester provides a new tool for mimicking the effects of caloric restriction that can be used in future research. The ability to power mitochondria in aged individuals that have limited ability to oxidize glucose metabolites due to pyruvate dehydrogenase inhibition suggests new lines of research for preventative measures and treatments for aging and aging-related disorders.

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