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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.
11

Transient impressions : designing breaking and changing textile expressions

TALMAN, RIIKKA January 2014 (has links)
'Transient impressions' explores breaking and changing qualities in textiles. Sustainability and people’s relationship to textiles are discussed through decomposing and changing processes in textile material and through different life-spans of materials. The project proposes a way of working with textile material, where expressions are designed to change over different periods of time. / Program: Konstnärligt masterprogram i mode- oh textildesign
12

振動彈簧的擾動性質 / On the perturbation of vibrating spring

洪三原 Unknown Date (has links)
In this work we deal with the nonlinear o.d.e u"+ku = εu<sup>3</sup> which represents a spring-mass system with no damping but perturbed by external force εu<sup>3</sup>. We want to know how the spring constant k and the perturbed term act on the equation. So we study this equation by the way: (I) u" + ku = 0 (II)u" = u<sup>3</sup> (III) u" + ku = εu<sup>3</sup> During the period of calculating, we find that k, ε and energy constant E(0) play important roles in the properties of the solutions of the equation. Finally we give the relation about them.
13

A LIFE SPAN APPROACH TO THE RELATIONSHIP BETWEEN CHOLESTEROL, LATE ONSET ALZHEIMER’S DISEASE, AND COGNITIVE FUNCTIONING AMONG OLDER ADULTS

Downer, Brian 01 January 2014 (has links)
There is evidence that cholesterol presents an important risk factor for Alzheimer’s disease (AD), but the direction of this relationship is modified by age. High cholesterol during midlife and low cholesterol during late life are both associated with an increased risk for AD. This dissertation research engaged a life span approach to study the relationship between cholesterol, AD and cognitive functioning among older adults. The purpose of this research was to determine if trajectories of cholesterol from midlife through late life differ according to AD status and if these trajectories are associated with cognitive functioning during old age. This research employed a secondary analysis of cognitive, phenotypic and genetic data collected from subjects of the Framingham Heart Study (FHS) Original and Offspring Cohorts. Aim One involved creating three summary scores of the FHS neuropsychological battery. ROC analysis was used to determine which score best differentiated between cognitively normal, impaired and dementia subjects. Aim Two used generalized additive mixed models to examine trajectories of total, HDL and total/HDL cholesterol ratio according to AD status in the Original Cohort. Aim Three used mixed-effects models to examine the relationship between subject-specific trajectories of total cholesterol and cognition during old age. Aim One determined that a summary score that provided equal weight to each assessment in the FHS neuropsychological battery best differentiates between subjects classified as cognitively normal, cognitively impaired and dementia. The findings from Aim Two indicated that there are subtle differences in the longitudinal trajectories of total, HDL and total/HDL ratio according to AD status. The findings from Aim Three provide limited evidence for a relationship between subject-specific trajectories of total cholesterol and cognitive functioning later in life. Older adults in the highest quartile for cognitive functioning had lower total cholesterol at approximately 55 years of age, but there were no differences in the mean trajectories of total cholesterol according to cognitive functioning later in life. The findings from this research suggest that older adults with high cognitive functioning have lower total cholesterol during midlife, but life span cholesterol trajectories do not appear to be associated with AD status or cognitive function.
14

Older workers :

Hartmann, Linley. Unknown Date (has links)
Thesis (MBus) -- University of South Australia, 1992
15

Measuring Future Time Perspective across Adulthood: Development and Evaluation of a Brief Multidimensional Questionnaire.

Brothers, A., Chui, Helena, Diehl, H. 21 April 2015 (has links)
PURPOSE OF THE STUDY: Despite calls for the consideration of future time perspective (FTP) as a multidimensional construct, mostly unidimensional measurement instruments have been used. This study had two objectives: (a) to develop a brief multidimensional questionnaire for assessing FTP in adulthood and evaluate its psychometric properties; and (b) to examine age associations and age-group differences of the dimensions of FTP. DESIGN AND METHODS: Data were collected from 625 community-residing adults between the ages of 18 and 93, representing young, middle-aged, and older adults. The psychometric evaluation involved exploratory factor analyses (EFA) and confirmatory FA (CFA), reliability and validity analyses, and measurement invariance testing. Zero-order and partial correlations were used to examine the association of the dimensions of FTP with age, and multivariate analysis of variance was used to examine age-group differences. RESULTS: EFA and CFA supported a three-factor solution: Future as Open, Future as Limited, and Future as Ambiguous. Metric measurement invariance for this factor structure was confirmed across the three age groups. Reliability and validity analyses provided evidence of sound psychometric properties of the brief questionnaire. Age was negatively associated with Future as Open and positively associated with Future as Limited. Young adults exhibited significantly greater ambiguity toward the future than middle-aged or older adults. IMPLICATIONS: This study provides evidence in support of the psychometric properties of a new brief multidimensional FTP scale. It also provides evidence for a pattern of age associations and age-group differences consistent with life-span developmental theory.
16

Life Histories of Women in Coaching

McCharles, Beth Lynne 21 April 2010 (has links)
The Canadian sport system is challenged by the lack of representation of female leaders and coaches. This is, in spite of statistics showing that female athletes account for almost half of all participants in sport, a number that is still growing (Sport Canada, 1999). Women have acquired equity in many areas of life and are accepted in leadership roles, however in the area of sport, women have yet to gain the full credibility and professional respect equal to their male counterparts. Previous research indicates that women who pursue a career in coaching face many adversities and struggle to attain a level of leadership where they can achieve their highest potential (Acosta & Carpenter, 2002). The purpose of this research is to gain an understanding of the lived experiences of elite female coaches, using Erikson’s (1950) theory of psychosocial development. In this study, the qualitative method of life history was used to learn about the experiences of female coaches, specifically the process of becoming and being elite coaches. Five elite Canadian coaches were interviewed. The major themes that developed through the analysis of the interviews were: (a) Support, (b) Overcoming Obstacles, (c) Personal Qualities and (d) The Bigger Picture. The study noted the importance of various support systems through one’s lifespan and some of the challenges a female athlete and coach must overcome to become a successful athlete, coach and mother. The study shares insight into the five women’s personal qualities that helped them grow into elite coaches. Finally, the participants described the process by which they came to find a leadership style with which they were comfortable, as coaches and as women.
17

Caracterização da tolerância ao estresse oxidativo, capacidade de remoção de proteínas oxidadas e a expectativa de vida de linhagens da levedura S. cerevisiae com mutações sítio-específicas na subunidade &alpha;5 do proteassomo 20S: implicações na prevenção de agregação. / Characterization of tolerance to oxidative stress, capacity to remove oxidized proteins and the life span of the yeast S. cerevisiae with site-specific mutations in the &alpha;5 subunit of the 20S proteasome: implications in the prevention of protein aggregation.

Ohara, Erina 04 September 2015 (has links)
O proteassomo é um complexo proteico responsável pela degradação de proteínas poli-ubiquitinadas. É constituído por uma unidade catalítica denominada de proteassomo 20S (20SPT) e por unidades regulatórias (19S) acopladas em uma ou ambas as extremidades para formar o proteassomo 26S. O 20SPT é capaz de degradar proteínas por um processo independente de ATP e ubiquitina. Este mecanismo é considerado preventivo de agregação proteica, uma vez que o acúmulo de proteínas oxidadas está diretamente associado ao envelhecimento e doenças neurodegenerativas. Foi observado pelo grupo que o 20SPT da levedura S.cerevisiae sofre S-glutatiolação nos resíduos de Cys 76 e Cys 221 da subunidade 5. Dados obtidos por microscopia eletrônica de transmissão mostraram que a S-glutatiolação promove a abertura da câmara catalítica e consequentemente o aumento da degradação de proteínas. Recentemente, foram obtidas linhagens com mutações sítio-específicas pela substituição dos dois resíduos de Cys glutatioláveis pela Ser. Ensaios realizados com a linhagem C221 mostraram um aumento da longevidade e resistência ao estresse oxidativo quando comparada com a linhagem selvagem, enquanto que a linhagem C76 mostrou uma dificuldade no crescimento. Foi verificado também que a população de proteassomo isolada da linhagem C221 apresenta maior proporção da forma aberta da câmara catalítica. Resultados opostos foram observados na linhagem C76S. No entanto, constatamos um aumento de proteínas oxidadas e de agregados proteicos na linhagem C221 em comparação a selvagem. Esses dados não condizem com o aumento do tempo de vida cronológico desta linhagem, porém acreditamos que esses agregados estejam relacionados a um tipo de sequestro de proteínas potencialmente prejudiciais, como será discutido neste trabalho. / The proteasome is a protein complex responsible for the degradation of poly-ubiquitinated proteins. It comprises a catalytic unit called 20S proteasome (20SPT) and regulatory units (19S) coupled at one or both ends to form the 26S proteasome. The 20SPT is able to degrade proteins by an ATP and ubiquitin independent process. This mechanism is considered preventive of protein aggregation, since the accumulation of oxidized proteins is directly related to aging and neurodegenerative diseases. It was observed by our group that the yeast 20SPT (S. cerevisiae) is modified by S-glutathiolation in the residues Cys 76 and Cys 221 of the 5 subunit. Data obtained by transmission electron microscopy showed that the S-glutathiolation promotes the opening of the catalytic chamber and consequently increased degradation of oxidized proteins. Recently, strains were obtained by site-specific mutations by replacing the two glutathiolable Cys residues by Ser. Tests performed with the C221 strain showed an increased longevity and resistance to oxidative stress when compared to the wild type strain, whereas the C76 strain showed a slower growth. It was also found that the isolated population of the 5-C221S proteasome presents the highest frequency of open catalytic chamber conformation. Opposite results were observed in the C76S lineage. However, we noted an increased pool of oxidized proteins and protein aggregates in the C221 strain compared to the wild type. These data do not match with the increase of chronological life span observed in this lineage, but we believe that these aggregates are related to a kind of \"sequestration\" of potentially damaging proteins, as will be discussed in this work.
18

Os 120 anos da vida do homem: uma análise contextual / The 120 years of human life: a contextual analysis

Hubner, Manu Marcus 14 August 2015 (has links)
Através dos números, os homens são capazes de comparar, ordenar, medir e quantificar tudo o que há à sua volta. Além da sua utilização para a matemática, muitos números receberam significados simbólicos. Na Bíblia Hebraica, os números são freqüentes, e possuem diversas funções e significados. Alguns números se destacam, como é o caso do número cento e vinte, utilizado para medidas ou contagens de tempo, espaço (áreas ou territórios), peso, pessoas ou animais. Este número figura no Livro do Gênese (6:3), como medida de tempo, no momento em que um limite de cento e vinte anos é decretado como expectativa máxima de vida do homem uma punição às transgressões do homem, falível e mortal, comparável à expulsão de Adão e Eva do Jardim do Éden (Gn 3:23-24) ou à diversificação das línguas faladas durante o episódio da Torre de Babel (Gn 11:7). Este decreto é estabelecido em uma interpolação de uma narrativa lacônica, aparentemente mitológica, em que seres conhecidos como filhos de Deus se relacionam com as filhas dos homens, dando origem a descendentes conhecidos como gigantes ou heróis. O número cento e vinte está relacionado ao período de cento e vinte anos em que Noé construiu a arca para sobreviver ao dilúvio (Gn 6), aos cento e vinte dias em que Moisés esteve sobre o Monte Sinai em três períodos de quarenta dias cada (Ex 24:12-18, 32:15, 30-31, 34:4, 29), como também ao período de três gerações convencionais de quarenta anos cada, exemplificado pelo pacto de Deus com o povo de Israel: ...guardes todos os Seus estatutos e os Seus preceitos que eu te ordeno tu, teu filho e o filho de teu filho... (Dt 6:2). Assim, apesar de que o número cento e vinte possui uma quantidade enorme de divisores, sua subdivisão em três períodos ou gerações de quarenta anos cada possui um simbolismo que instiga a investigação. / Through the numbers, men are able to compare, sort, measure and quantify everything there is around them. Besides their use for mathematics, many numbers have symbolic meanings. In the Hebrew Bible, numbers are frequent, and have different functions and meanings. Some numbers are highlighted, such as the number one hundred and twenty, used to measure or counting of time, space (areas or territories), weight, people or animals. This number can be found in the Book of Genesis (6:3), as a measure of time, at the moment when a limit of one hundred and twenty years is decreed as the maximum life expectancy of man a punishment for man\'s transgressions comparable to the expulsion of Adam and Eve from the Garden of Eden (Gen. 3:23-24) or the confusion of speech during the episode of the Tower of Babel (Gen. 11:7). This decree is established on an interpolation of a seemingly mythological, laconic narrative in which beings known as the \"sons of God\" had relationships to the \"daughters of men\", giving rise to offspring known as \"giants\" or \"heroes\". The number one hundred and twenty is related to the period of one hundred and twenty years in which Noah built the ark to survive the flood (Gen. 6), to one hundred and twenty days in which Moses was on Mount Sinai in three forty-day periods each (Ex 24 :12 -18 , 32:15 , 30-31 , 34:4, 29), as well as the conventional period of three generations of forty years each, exemplified by the covenant of God with the people of Israel: \" ... keep all His rules and laws that I am prescribing to you you, your children and your childrens children\" (Deut. 6:2). Thus, although the number one hundred and twenty has a huge amount of dividers, its subdivision into three periods or generations of forty years each has a symbolism that instigates the investigation.
19

Análise proteômica diferencial da levedura Saccharomyces cerevisiae após mutações sítio-específicas de resíduos de Cys do Proteassomo 20S: implicações com a expectativa de vida celular. / Differential proteomic analysis in the yeast Saccharomyces cerevisiae after stie-specific mutations of Cysteine residues in the 20S proteasom: Implications in the life span.

Santiago, Verônica Feijoli 17 September 2018 (has links)
A oxidação de proteínas é um fenômeno metabólico e a degradação de proteínas oxidativamente modificadas confere uma proteção para a célula, evitando acúmulo e a agregação das mesmas. A ineficiência na remoção destas proteínas está relacionada ao processo de envelhecimento e ao aparecimento de doenças neurodegenerativas. A unidade catalítica do proteassomo, denominada de 20S (PT20S), é a principal via de degradação de proteínas danificadas pela oxidação sem que haja gasto de ATP, acoplamento de subunidades regulatórias ou poli-ubiquitinação do substrato proteico. A unidade PT20 por sua vez, pode sofrer modificação pós-traducional chamada de S-glutationilação, que aumenta a velocidade degradação proteica por processo independente de poli-ubiquitinação. Em levedura (Saccharomyces cerevisiae), foram identificados apenas dois resíduos de Cys glutationilados, ambos na subunidade &#945;5 (&#945;5-76 e &#945;5-221). A S-glutationilação ocasiona a abertura da câmara catalítica e uma maior eficiência na degradação de proteínas. Mutações sítio-específicas foram realizadas nessas Cys pela substituição por Ser. As consequências estruturais e funcionais dessas mutações foram o aumento da frequência da conformação fechada da câmara catalítica no &#945;5-76S-PT20S e &#945;5-221S-PT20S. As linhagens que carregam essas mutações apresentaram menor tempo de vida cronológico. Uma dupla mutação randômica na subunidade &#945;5 (S35P / C221S) induziu a abertura da câmera catalítica do 20SPT e esta linhagem apresentou tempo de vida cronológico significativamente aumentado e , aumento na resistência ao estresse oxidativo em paralelo ao aumento da atividade catalítica do 20SPT. O objetivo neste projeto de pesquisa foi realizar uma análise proteômica quantitativa no extrato celular das linhagens mutantes, com o objetivo de identificar proteínas que possam estar relacionadas com a regulação da longevidade celular. Foram selecionadas as linhagens que carregam as mutações: &#945;5-76S e &#945;5-S35P/C221S uma vez que apresentaram expectativa de vida oposta em relação à linhagem selvagem, além de queda e aumento da frequência da conformação aberta da câmera catalítica, respectivamente. A partir da quantificação sem marcação (Label-free quantification), foram identificadas 723-1000 proteínas nas amostras das linhagens selvagem e mutantes. Dentre elas, destacam-se as proteínas 3-isopropilmalato isomerase e argininossuccinato sintase, envolvidas na síntese de leucina e arginina, respectivamente, aumentadas na linhagem mutante C76S e reduzidas na linhagem S35P/C221S. O metabolismo de ambos os aminoácidos está relacionado com a via de sinalização TOR que, por sua vez, está envolvida com o tempo de vida cronológico em levedura. / The protein oxidation is a metabolic phenomenon and the degradation of oxidatively modified proteins confers a protection to cell, avoiding accumulation and aggregation of these proteins. The inefficiency in the removal of these proteins is related to aging process and neurodegenerative diseases. The catalytic unit of the proteasome, named 20S (PT20S) is the main degradative pathway of oxidized proteins in an ATP-independent manner, without proteasomal regulatory units assembly or protein poliubiquitination. The PT20 unit undergoes a post-translational modification named S-glutationilation, which increases the protein degradation by the ATP-independent process. In yeast, only two Cys residues were identified glutationilated, both in the &#945;5 subunit (&#945;5-C76 e &#945;5-C221). The S-glutationilation causes opening of the catalytic chamber and higher efficiency of protein hydrolysis. Site-specific mutations were performed in those Cys residues by their replacement to Ser. The structural and functional consequences of mutations were the increasedfrequency of theclosed conformation of the catalytic chamber in the &#945;5-76S-PT20S and &#945;5-221S-PT20S. The strains carrying those mutations presented shorter chronological life span. A double random mutation in the &#945;5 subunit (S35P / C221S) induced the opening of 20SPT catalytic chamber together toextended chronological life span and, increased resistant to oxidative stress in parallel to increased catalytic activity of the 20SPT. The goal of this project was to perform a label-free quantitative proteomic analysis in the mutant strains to identify proteins that could be related with the regulation of cellularlifespan. From that quantification, 723 - 1000 proteins were identified in the samples of the wild-type and mutant strains. Among these proteins, 3-isopropylmalate isomerase and argininesuccinate sintase, involved in the leucine and arginine biosynthesis, respectively, were found increased in the C76S mutant strain and reduced in the S35P/C221S mutant strain. The metabolism of both amino acids is related with TOR signallingthat, in turn,modulates chronological lifespan in yeast
20

Os 120 anos da vida do homem: uma análise contextual / The 120 years of human life: a contextual analysis

Manu Marcus Hubner 14 August 2015 (has links)
Através dos números, os homens são capazes de comparar, ordenar, medir e quantificar tudo o que há à sua volta. Além da sua utilização para a matemática, muitos números receberam significados simbólicos. Na Bíblia Hebraica, os números são freqüentes, e possuem diversas funções e significados. Alguns números se destacam, como é o caso do número cento e vinte, utilizado para medidas ou contagens de tempo, espaço (áreas ou territórios), peso, pessoas ou animais. Este número figura no Livro do Gênese (6:3), como medida de tempo, no momento em que um limite de cento e vinte anos é decretado como expectativa máxima de vida do homem uma punição às transgressões do homem, falível e mortal, comparável à expulsão de Adão e Eva do Jardim do Éden (Gn 3:23-24) ou à diversificação das línguas faladas durante o episódio da Torre de Babel (Gn 11:7). Este decreto é estabelecido em uma interpolação de uma narrativa lacônica, aparentemente mitológica, em que seres conhecidos como filhos de Deus se relacionam com as filhas dos homens, dando origem a descendentes conhecidos como gigantes ou heróis. O número cento e vinte está relacionado ao período de cento e vinte anos em que Noé construiu a arca para sobreviver ao dilúvio (Gn 6), aos cento e vinte dias em que Moisés esteve sobre o Monte Sinai em três períodos de quarenta dias cada (Ex 24:12-18, 32:15, 30-31, 34:4, 29), como também ao período de três gerações convencionais de quarenta anos cada, exemplificado pelo pacto de Deus com o povo de Israel: ...guardes todos os Seus estatutos e os Seus preceitos que eu te ordeno tu, teu filho e o filho de teu filho... (Dt 6:2). Assim, apesar de que o número cento e vinte possui uma quantidade enorme de divisores, sua subdivisão em três períodos ou gerações de quarenta anos cada possui um simbolismo que instiga a investigação. / Through the numbers, men are able to compare, sort, measure and quantify everything there is around them. Besides their use for mathematics, many numbers have symbolic meanings. In the Hebrew Bible, numbers are frequent, and have different functions and meanings. Some numbers are highlighted, such as the number one hundred and twenty, used to measure or counting of time, space (areas or territories), weight, people or animals. This number can be found in the Book of Genesis (6:3), as a measure of time, at the moment when a limit of one hundred and twenty years is decreed as the maximum life expectancy of man a punishment for man\'s transgressions comparable to the expulsion of Adam and Eve from the Garden of Eden (Gen. 3:23-24) or the confusion of speech during the episode of the Tower of Babel (Gen. 11:7). This decree is established on an interpolation of a seemingly mythological, laconic narrative in which beings known as the \"sons of God\" had relationships to the \"daughters of men\", giving rise to offspring known as \"giants\" or \"heroes\". The number one hundred and twenty is related to the period of one hundred and twenty years in which Noah built the ark to survive the flood (Gen. 6), to one hundred and twenty days in which Moses was on Mount Sinai in three forty-day periods each (Ex 24 :12 -18 , 32:15 , 30-31 , 34:4, 29), as well as the conventional period of three generations of forty years each, exemplified by the covenant of God with the people of Israel: \" ... keep all His rules and laws that I am prescribing to you you, your children and your childrens children\" (Deut. 6:2). Thus, although the number one hundred and twenty has a huge amount of dividers, its subdivision into three periods or generations of forty years each has a symbolism that instigates the investigation.

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