Caloric restriction (CR) extends lifespan from yeast to mammals. In budding yeast, inhibition of the conserved TOR and/or PKA pathways has been shown to mediate lifespan extension by CR partly through the activation of stress response. However, how the stress response is regulated at the systems level is poorly understood. In this study, by using fluorescent reporters whose expression is dependent on the transcription factors Msn2/4 and Gis1, two separate screenings were conducted to reveal novel regulators of the stress response induced by starvation. A 'focused' screening on the 272 'signalling' mutants revealed that, apart from the previously identified Rim15, Yak1 and Mck1 kinases, the SNF1/AMPK complex, the cell wall integrity (CWI) pathway and a number of cell cycle regulators are necessary to elicit appropriate stress response. The chronological lifespan (CLS) of these signalling mutants correlates well with the amount of accumulated storage carbohydrates but poorly with transition-phase cell cycle status. Subsequent analyses reveal that the levels of intracellular reactive oxygen species are controlled by Rim15, Yak1 and Mck1. Furthermore, CLS extension enabled by tor1 deletion is dependent on the above three kinases. These data suggest that the signalling pathways (SNF1 and CWI) and the kinases downstream of TOR/PKA (Rim15, Yak1 and Mck1) coordinate the metabolic reprogramming (to accumulate storage carbohydrates) and the activation of anti-oxidant defence systems (to control ROS levels) to extend chronological lifespan. A 'genome-wide' screening of a haploid deletion library indicates that less than 10% of the non-essential genes are implicated in the regulation of starvation-induced stress response. Gene ontology analysis suggests that they can be grouped into major clusters including mitochondrial function, r-RNA processing, DNA damage and repair, transcription from RNA polymerase and cell cycle regulation. Further phenotypic assays confirm the previous observation that CLS extension is mostly correlated with the accumulation of storage carbohydrates. Compromised expression of stress response reporters is confirmed by FACS in a variety of mitochondrial mutants, suggesting that mitochondrial respiration also plays a key role in the activation of stress response. Put together, the above findings indicate that stress response and metabolic reprogramming induced by glucose starvation are coordinated by multiple signalling pathways and the activation of mitochondrial respiration is essential to both cellular processes and to CLS extension.

In this thesis, I am concerned with the language of advertising. By analyzing advertising from a discourse perspective, this paper further examines the context of communication and the participants’ roles in the context. This study focuses on commercial advertising, based on the assumption that the intended meaning of the advertiser is to persuade the viewer to perform a purchase. Therefore this study observes persuasive messages and how they are presented in advertising. To analyze and compare real texts from a discourse perspective present an opportunityto examine social changes that might have taken place in a society due to different temporal settings. The social changes are examined by comparing assigned gender roles in advertisements published in 1956 and advertisements published in 2014. The material consists of a total of eleven transcripts description of printed advertisements collected from The New Yorker. The examples used for this study have been hand picked to illustrate theories described in the background, such as those provided by Leech (1966), Hermerén (1999), Romaine (1999), Cronin (2000) and Hillier (2004). The framework for the analysis is based on Leech’s (1966) concept of primary and secondary situations with corresponding primary and secondary participants. The findings suggest that advertisers can persuade the viewer by addressing the viewer directly and by using exophoric references, or by inserting secondary participants to convey the message. In addition, the assigned role of women seems to have changed more than the assigned role of men in advertising discourse.

Prions are infectious protein entities capable of self-replication. Prions are the causal agents behind the transmissible spongiform encephalopathies causing neurodegeneration and death in affected organisms. Prions have been identified in yeast with the best-characterized prions being [PSI+] and [PIN+], whose respective native proteins are the Sup35 translation termination factor and Rnq1 (function unknown). Autophagy is a cellular housekeeping mechanism mediating the degradation of damaged proteins and superfluous organelles. It is a highly sequential process regulated by autophagy related genes (ATGs). Autophagy has also been implicated in the clearance of amyloidogenic proteins including prions. However, the mechanistic basis underlying this activity is poorly understood, and a key objective of this project was to characterize how autophagy prevents spontaneous prion formation. Our study found that the deletion of core ATGs correlated with an increase in de novo [PSI+] and [PIN+] formation as well as Sup35 aggregation. Enhancement of autophagic flux through spermidine treatment attenuated the increased levels of de novo [PSI+] formation in mutants that normally show elevated levels of [PSI+] formation. Defective autophagy correlated with increased oxidatively damaged Sup35 in an atg1 mutant whereas anaerobic growth abrogated the increased [PSI+] formation in the atg1 mutant to wild-type levels. Our data suggest that autophagy serves a protective role in the clearance of oxidatively damaged Sup35 proteins that otherwise has a higher propensity towards [PSI+] prion formation. We also investigated the role of prion formation and autophagy during yeast chronological ageing which is the time that non-dividing cells remain viable. Prion diseases are associated with advanced age which correlates with a decline in cellular protective mechanisms including autophagy. Our study found an age dependent increase in the frequency of de novo [PSI+] formation with chronological age of yeast cells, more so in an atg1 mutant relative to the wild-type. Autophagy competent cells carrying the [PSI+] and [PIN+] prions also had improved chronological lifespan relative to prion free cells and atg1 cells. Cells carrying the [PSI+] prion elicited elevated autophagic flux that may promote improved lifespan thus suggesting a beneficial role of the [PSI+] prion during chronological ageing. The actin cytoskeleton provides the structural framework essential for a multitude of cellular processes to occur. We investigated the role of the Arp2/3 complex responsible for branching of actin filaments towards prion formation. Knockout mutants of the nucleation promoting factors of the Arp2/3 complex, in particular the abp1 mutant, showed reduced de novo [PSI+] formation and Sup35 aggregation under basal and oxidative stress conditions. Similarly, treatment with latrunclin A, an actin monomer-sequestering drug also abrogated de novo [PSI+] formation. Colocalization studies revealed that Sup35 often does not colocalize with Rnq1, a marker for the insoluble protein deposit (IPOD) in an abp1 mutant. This suggests a role for the Abp1 protein in the efficient transport of Sup35 molecules to the IPOD that may facilitate de novo [PSI+] prion formation under vegetative states and oxidant challenges.

Magister Scientiae Dentium - MSc(Dent) / Background: Dental age is an indicator of the physiological maturity of growing children. Different methods for estimating the dental age in comparison to the chronological age were proposed in the literature. Objective: The aim of this study was to compare the accuracy of two methods i.e. the Phillips and Proffit methods in estimating the dental age in a sample of South African children at the Tygerberg dental faculty. Methods: A retrospective study was conducted by randomly selecting 100 panoramic radiographs with known chronological age. The sample contained an equal number of girls and boys (50 in each group) and the chronological age ranged between 6 and 11 years. Dental age for each radiograph was estimated using the Phillips and the Proffit methods respectively. The mean difference between dental and chronological age was calculated. Dental and chronological ages were compared using overall bias and random errors. Results: The results showed that for the girls’ sample, the Phillips method underestimated the age by 4 months which is statistically significant (p-value =0.03). The Proffit method underestimated the age by 2 days which is not statistically significant (p-value =0.97). Both methods however have the same frequency of random errors. For the boys’ sample, Phillips’ method underestimated the age by 6 months which is statistically significant (p-value <0.0001). Proffit’s method underestimated the age by 2 months which is not statistically significant (p-value= 0.15). The Phillips method was shown to have fewer random errors in boys. Discussion: The above mentioned results showed that for dental age estimation for girls, Proffit’s method would be more appropriate. This rationale is explained by the conclusion that it only underestimates the age by 2 days and has the same frequency of random errors as Phillips’ method. However, if one had to choose between the two methods for boys, the situation should be evaluated carefully. For boys, the Phillips method has fewer random errors but a larger overall bias (6 months) whereas Proffit’s method has more random errors but less overall bias (2 months). The choice between the two methods should therefore depend on the purpose of the estimation. If the method is used for estimating the age in a single individual with an unknown chronological age, Phillips’ method would be more preferable. However, if the method is used for age estimation in populations with a known mean chronological age, Proffit is preferred. Conclusion: Proffit’s description for dental development has been shown to be accurate in estimating the DA. It may therefore be considered to be a legitimate DA estimation method and not just a developmental description for the dentition.

Magister Chirurgiae Dentium (MChD) / Aging is a biological process under the influence of genetic and pathological factors wh ich can be more or less advanced in different individuals with the same, chronological age. Silverman (1961) defined age as a three-dimensional phenomenon wherein there is a constant interaction between chronologie age, physiologic age and psychologic age. Vinton (1964) also points out that there are physiologic, pathologic, psychologic and sociologic changes which are unique to the latter span of life. These changes are not synonomous with illness as long as they fall within the physiologic limits of normality. If these limits are exceeded the changes are pathological in character. Age is a phase of life which brings about changed circumstances and a new pattern of life which must be adapted to and accepted. This may necessitate an invironmental change which causes a loss of friends and social standing and may bring about a feeling of insecurity in some people, suppressing the incentive to live for the future. To counter these emotions it is imper~tive to create a quality of life in which the aged can be productive within the limits of their physical abilities and which will give them the assurance that they are still needed by society. Life expectancy is determined by the circumstances under which people live. The average age of life expectancy during the Roman period and the Middle Ages was 25 to 30 years; today it is 70 years (Sharry 1974). Nature normally maintains an equilibrium between young and old so that each can provide for the other's needs. Modern science and technology however have upset that balance and brought about new developments in medicine ich have succeeded in increasin and reducin infant mortality, causing the ectancy explosion. This has brought about a situatiop where 10 million humans are born and only 3 million die every month; thus the inflow into life far exceeds the outflow and there is consequently a global increase of 80 million people per year. At this rate the world population will double itself by the end of this century (Pistorius 1978). Birth control has been encouraged as a counter measure to this and the result has been a marked drop in the birth rate, especially in the more advanced countries of the world. This changing relationship between the birth and death rates is referred to as the population-shift. In the U.S.A. 4% of the total population was over the age of 65 years at the beginning of this century. In 1975 the figure was 10% and at the present rate of population-shift will be 20% by the end of this century (Winkler 1977). In England and Wales 6% of the total population was over the age of 65 years in 1931, 10% in 1951 and 12% in 1962. In Scotland 7% was over the age of 65 years in 1931, 9% in 1951 and 10% in 1962 (Storer 1965). In Canada 4,8% of the total population was over the age of 65 years in 1921 and 7,8% in 1971. The average life expectancy was 50 years in 1900 and 70 years in 1960 (Sherman 1970). This pattern of change is also evident in the Republic of South Atrica but there is a marked variation in the different ethnic groups (White, Asian, Coloureds and Blacks) making up the South African population.

Shortest-path network analysis was employed to identify novel genes that modulate longevity in the baker’s yeast Saccharomyces cerevisiae. Based upon a set of previously reported genes associated with increased life span, a shortest path network algorithm was applied to a pre-existing protein-protein interaction dataset in order to construct a shortest-path longevity network. To validate this network, the replicative aging potential of 88 single gene deletion strains corresponding to predicted components of the shortest path longevity network was determined. The 88 single-gene deletion strains identified by a network approach are significantly enriched for mutation conferring both increased and decreased replicative life span when compared to a randomly selected set of 564 single-gene deletion strains or to the current data set available for the entire haploid deletion collection. In addition, previously unknown longevity genes were identified, several of which function in a longevity pathway believed to mediate life span extension in response to dietary restriction. This study represents the first biologically validated application of a network construct to the study of aging and rigorously demonstrates, also for the first time, that shortest path network analysis is a potentially powerful tool for predicting genes that function as potential modulators of aging.

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

<p>The study of work motivation has yielded many applicable theories. This thesis investigated how older employees viewed factors that have been linked to the advancement of age and believed to affect work motivation. Three different conceptualisations of age were included in the study; organisational age, chronological age and life stage. By using a qualitative approach, participants were allowed to shed light on this complex area and give their own views on possible age effects. More specifically, changes in needs and values, the effects on goal setting and the development of skills were investigated. Chronologically younger employees placed greater value in their careers and reported that they would continue to work even if they became financially independent. Older employees attributed less importance to their careers and said that they would choose early retirement in order to have more time if they had money to enjoy it.</p>

The study of work motivation has yielded many applicable theories. This thesis investigated how older employees viewed factors that have been linked to the advancement of age and believed to affect work motivation. Three different conceptualisations of age were included in the study; organisational age, chronological age and life stage. By using a qualitative approach, participants were allowed to shed light on this complex area and give their own views on possible age effects. More specifically, changes in needs and values, the effects on goal setting and the development of skills were investigated. Chronologically younger employees placed greater value in their careers and reported that they would continue to work even if they became financially independent. Older employees attributed less importance to their careers and said that they would choose early retirement in order to have more time if they had money to enjoy it.

This thesis investigates the question: Can Experience Design be applied to create a perception shift from elderly as a burden to elderly as a resource for society? This is done by researching the social norms about ageing and the aged in Swedish society. To conduct this research I put together a focus group of 7 people with different professional backgrounds and ages ranging from 23 to 74. In four workshops I used design-led research methods to research these “mental models”. Using participatory theatre techniques we investigated the personal view of the ageing process. And through discussions and design thinking we articulated the often unspoken social norms. In the workshops we defined our current social norms regarding ageing as Aged Thinking. A counter philosophy was developed called Ageless Thinking. In order to create a change in mindset from Aged Thinking to Ageless Thinking a tool was developed called the Enticon. With this tool people can show what their focus is in life right now regardless of their chronological age. The Enticon was introduced at the Konstfack Spring Exhibition 2013 and also as a web based application.