La première augmentation de la longévité en laboratoire fût observée à la suite d’une intervention nutritionnelle consistant en une réduction de l’apport alimentaire chez le rat. Plus tard, ce phénomène a été reproduit dans de très nombreuses espèces et référé en tant que restriction calorique. Le développement des techniques de biologie moléculaire moderne a permis de montrer dans des organismes modèles simples que cette flexibilité du processus de vieillissement était régulée par des facteurs génétiques. De fait, plusieurs mécanismes cellulaires ont alors pu être identifiés comme responsables de ce contrôle du vieillissement. Ces voies de régulation ont révélées être conservées entre les espèces, depuis les levures jusqu’aux organismes multicellulaires tels que le nématode, la mouche ou la souris, suggérant l’existence d’un programme universel de vieillissement dans le vivant. La levure s’est avéré à plusieurs reprises être un modèle puissant et fiable pour la découverte de gènes impliqués dans ce phénomène. Mon étude a consisté au développement d’un nouveau modèle unicellulaire d’étude du vieillissement à travers l’espèce Schizosaccharomyces pombe appelée aussi levure à fission. La première étape de mon travail a montré que les voies de détection des nutriments gouvernées par la sérine/thréonine protéine kinase A (Pka1) et la sérine/thréonine kinase Sck2 contrôlent le vieillissement chronologique de ces cellules comme il était connu dans la levure Saccharomyces cerevisiae. Ceci permit de valider l’utilisation de la levure à fission pour l’étude du vieillissement. Ensuite, nous avons analysé plus en détail l’effet pro-vieillissement du glucose en étudiant le rôle de sa détection par le récepteur membranaire Git3 couplé à la protéine G (Gpa2) en amont de la kinase Pka1. La perte du signal du glucose par la délétion de Git3 imite partiellement l’effet d’augmentation de longévité obtenu par baisse de la concentration en glucose dans le milieu. De plus, l’effet néfaste du signal du glucose est maintenu en absence de tout métabolisme du glucose suite à la mutation des hexokinases, premières enzymes de la glycolyse. L’ensemble de ces résultats suggèrent que la signalisation du glucose est prédominante sur son métabolisme pour son effet pro-vieillissement. D’autre part, à la fois la suppression de cette signalisation et la baisse de niveau de glucose disponible allongent la durée de vie en corrélation avec une augmentation de la résistance au stress, une hausse d’activité mitochondriale et une baisse de production de radicaux libres. Finalement, le criblage d’une banque de surexpression d’ADNc a permis d’identifier plusieurs gènes candidats responsables de ces effets en aval de la voie de signalisation Git3/PKA. La recherche sur les mécanismes moléculaires du vieillissement propose une nouvelle approche, un nouvel angle de vue, pour la compréhension des fonctions cellulaires et promet d’apporter de précieuses clefs pour mieux comprendre certaines maladies. En effet, le vieillissement est la première cause d’apparition de nombreuses affections comme les cancers, les maladies cardiovasculaires et métaboliques ou les maladies neurodégénératives tels que les syndromes d’Alzheimer et de Parkinson. / The first increase in life span due to man’s intervention was obtained with rats subjected to a diet reduced in calorie intake. Later, this phenomenon was repeated with many other species and referred as diet restriction or calorie restriction. The development of modern Molecular Biology approaches and the use of simple model organisms demonstrated that the rate of aging was regulated by genetic traits. Indeed, several cellular mechanisms were identified as responsible for the control of aging. These regulatory pathways appear to be conserved throughout species, from yeast to multicellular organisms like nematode, fly and mice, thus suggesting the existence of a universal program of aging. Yeast proved several times to be a powerful and reliable model for discovering genes involved in the regulation of aging. My study consisted in developing Schizosaccharomyces pombe (also called fission yeast) as a new unicellular model to study aging. The first step of my work was to show that pathways of nutrient detection through kinases involving Pka1 and Sck2 control chronological aging in S. pombe, as it was previously demonstrated in Saccharomyces cerevisiae. This first work validated the use of fission yeast for the study of aging. Subsequently, we analysed in more detail the pro-aging effect of glucose focusing on the role of its signalling through the G-protein Gpa2-coupled membrane receptor Git3, which acts upstream of Pka1. The loss of the glucose signal due to deletion of Git3 mimics partially the effect of increasing longevity by reducing glucose in the medium. Moreover, detrimental effects of glucose signal are maintained in absence of sugar metabolism following loss of hexokinases, the first enzymes of glycolysis. Together, these results suggest that the pro-aging effects of glucose signalling are predominant over those due to metabolism of this sugar. Moreover, both obliteration of this signalling pathway and decrease of glucose availability extend life span, and correlate with an increase in stress resistance, in mitochondrial activity and a lower production of free radicals. Finally, screening a cDNA-overexpression library allowed us to identify several genes candidates responsible for the effects on longevity downstream of Git3/Pka1. Research in the molecular mechanisms of aging propose holds the promise to bring precious clues as to this mysterious processes affecting all living creatures, and paves the way to unravel the underlying causes of many human diseases. Indeed, aging is the first cause of numerous late-onset pathologies including cancers, cardiovascular diseases or neurodegenerative diseases like Alzheimer and Parkinson syndromes.

A stereoselective synthesis of (25S)-Δ1-, (25S)-Δ1,4-, (25S)-Δ1,7-, (25S)-Δ8(14)-, (25S)-Δ4,6,8(14)-dafachronic acid, methyl (25S)-Δ1,4-dafachronate and (25S)-5α-hydroxy-3,6-dioxocholest-7-en-26-oic acid is described. (25S)-Δ1,4-Dafachronic acid and its methyl ester are natural products isolated from corals and have been obtained by synthesis for the first time. (25S)-5α-Hydroxy-3,6-dioxocholest-7-en-26-oic acid represents a promising synthetic precursor for cytotoxic marine steroids. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

The impact of transportation concerning older adults is under scrutiny as the number of older adults is expected to significantly increase in the coming years. The World Health Organization (WHO) spearheaded a world wide initiative that sought to examine what contributed to an “age-friendly community” in both developed and underdeveloped nations. This paper examines, in particular, the role that transportation plays in relation and contribution to an “age-friendly” community in Saanich, British Columbia, as an addition to the WHO initiative. Focus groups were conducted to ensure that information received was the lived experience of the individual. Results suggested that transportation was more than the ability to operate a vehicle, but in the ability to move safely within an environment. Additional information provided by participants spoke to the necessity of increasing awareness of licensing systems and improvements that could be implemented to ensure safety for older adult drivers and the community.

Aging, also in the absence of pathological conditions, is associated with cognitivedecline, especially in so called fluid abilities, such as episodic memory andexecutive functions. Due to an ongoing demographic shift, a larger part of thepopulation will reach higher ages, and more people will be affected by age-relatedcognitive decline. Finding ways of counteracting this development have the potentialof having large benefits for both individuals and society. It has long beenknown that living in environments that are rich in terms of cognitive challengescan affect cognitive ability in old age. In this regard, intervention studies in whichthe amount of cognitive stimulation is manipulated can therefore generate insightsto the causality of such effects in specific cognitive functions. Cognitive trainingas means to counteract negative effects of aging on cognition has received a lot ofscientific interest in the last decades.This focus of this thesis is cognitive training interventions, which is studiedfrom several perspectives. In Study i, the aim was to investigate the extent towhich executive functions can be strengthened by training in younger and olderadults, and to which degree such training generalize to other measures of cognition.Although a large body of research has been investigating training of workingmemory and executive functions in recent years, the results are diverse, and fewhave been targeting executive functions broadly with training programs based ontheoretical models of executive functions. Study i showed that despite a broadtraining program targeting three executive functions (updating, shifting and inhibition),it did not lead to transfer beyond the very near in old adults. The youngerhowever showed transfer effects to measures of working memory.In Study ii, the focus was on studying how the effects survive across time.There is limited knowledge about long-term effects of process-based training andthe results showed that the training effect was stable after 1.5 years, while only thenearest transfer effect was still significant in both younger and older adults.Study iii focused on individual factors affecting gain and maintenance thereofin a sample of older individuals. We used a strategy-based intervention focusingon episodic memory performance with a number-consonant mnemonic which is amnemonic for memorizing digit-codes. A different set of predictors was observedfor baseline episodic memory performance and training gain. Those that are betteroff in terms of episodic memory performance, also gain more in the episodic memorycriterion task. Further, a higher rate of processing speed was also important.Lastly, better verbal knowledge also influence gain beyond the other factors. Theresults have both theoretical implications regarding how plastic cognitive functionsare, and practical, in terms of how to best design training programs. / Över hela världen blir vi äldre. År 2050 kommer en femtedel av jordens befolkningvara 60 år eller äldre, att jämföra med en knapp tiondel år 1950. Det är förstås enpositiv utveckling men en åldrande befolkning innebär också att vi står inför flerautmaningar. En sådan rör det kognitiva åldrandet. Vi vet att åldrande kan leda tillnedgång i vissa kognitiva förmågor, såsom det episodiska minnet samt exekutivafunktioner. Episodiskt minne är vår förmåga att komma ihåg upplevda händelserknutna till tid och rum. Exekutiva funktioner är ett begrepp som inbegriper vårförmåga att hålla en plan aktiv medan vi utför den, utan att distraheras av tankareller externa störningsmoment. Genom att studera effekter av träning hos yngreoch äldre vuxna på sådana kognitiva funktioner kan vi få kunskap om till vilkengrad de kan förbättras och om denna förbättringspotential är olika beroende påålder. Vi vet sedan tidigare att människor som under sin livstid lever ett kognitivtstimulerande liv också till viss del är skyddade mot nedgång i kognition underåldrandet. Träningsstudier kan ge kunskap om kausaliteten i sådana fynd.Studie i i denna avhandling behandlar träning av exekutiva funktioner föryngre och äldre vuxna. Träningsprogrammet konstruerades utefter en teoretiskmodell som beskriver exekutiva funktioner som bestående av förmågan att inhiberastörande stimuli eller överlärda responser, förmågan att uppdatera informationi arbetsminnet, och förmågan att skifta mellan att utföra olika uppgifter. Resultatenvisade att de yngre kunde generalisera träningseffekten också till otränadearbetsminnesuppgifter, medan de äldre endast visade förbättring på otränade uppgiftersom hade stora likheter med de tränade.I Studie ii undersöktes hur mycket av träningseffekterna som kvarstod ettoch ett halvt år efter träningen. Resultaten visade att både för yngre och äldreså kvarstod effekten på tränade uppgifter samt en av uppgifterna som hade stortöverlapp med träningsuppgifterna, för både unga och äldre.I Studie iii studerades ett strategibaserat träningsprogram för episodisktminne. Fokus låg på att undersöka vilka individuella kognitiva faktorer sompåverkar förbättring som följd av träning. Resultaten visade att de med högre förmågai kognitiv bearbetningshastighet samt verbal förmåga var de som hade bästförutsättningar för förbättring.Resultaten från dessa studier är av både teoretisk relevans i och med att deökar förståelsen för träningsbarheten av exekutiva funktioner, samt har praktiskrelevans för utformning av träningsprogram.

Background and aim: As an experienced paediatric nurse I have recognised that adolescents with persistent chronic childhood diseases fall between two chairs. International studies support this recognition. Norwegian adolescents with juvenile idiopathic arthritis are no exception. Chronic arthritis from childhood might have far-reaching consequences for the growth and development of the child, and for the family and community. The fact that a considerable proportion of children with JIA continue to have active disease and disease residua through adolescence into adulthood underlines the importance of illuminating the situation in a public-health perspective. Through this study I aim at exploring physical and psychosocial health among young adults with JIA in a life-span perspective from childhood and adolescence into adult life. Methods: The thesis has a qualitative and a quantitative approach. Study I had an abductive explorative design. The experiences and perceptions of health-care transition were explored by focus-group interviews with young people with JIA and related health professionals respectively. Qualitative content analysis was utilised. Study II had an abductive explorative design with qualitative interviews to explore young adults’ experiences of living with JIA in a life-span perspective. Qualitative content analysis was utilised. Study III had a longitudinal deductive design. The standardised questionnaires of Health Assessment Questionnaire, General Health Questionnaire version 30, and Visual Analogue Scales of pain, fatigue, and illness were utilised to explore physical ability, psychosocial health, pain, fatigue, and illness in a cohort of patients with JIA 18.3 years after symptom-onset. Comparisons with baseline and first follow-up were performed. Data were analysed by descriptive statistics and non parametric tests. Study IV had a cross-sectional deductive design. In addition to the questionnaires utilised in study III, the questionnaire of SF-36 Health Survey and data on education, employment, need of assistive equipment at work, and use of health services the previous year were employed. Comparisons with Norwegian population- based data were performed. Data were analysed by descriptive statistics, and parametric and non parametric tests. Findings: In study I, ability to live a meaningful and responsible adult life seemed to be a common goal. Obstacles for the young people were the nature of the disease, a lack of focus on transition processes, and overprotective parents and health professionals. Obstacles for the health professionals were lack of inter-professional and inter-institutional formal co-operation and agreed practice, and lack of competence on adolescent development and health. Study II demonstrates that living with JIA implies a constant oscillation between struggle and adjustment to an insecure everyday life and an unpredictable life course. This was expressed as bodily experiences of limitation and freedom, interpersonal experiences of being included or set on the sidelines, and intrapersonal perceptions of insecurity and confidence. Of the 55 young adults with JIA in study III, 21 reported physical disability, and 12 reported psychiatric distress within the clinical range. Furthermore, 26 patients reported illness, 27 pain, and 33 fatigue above 10 on the VAS scale (0-100). Significant correlations were found between physical disability, pain, illness and fatigue, and between psychiatric distress, pain, and fatigue. Comparisons from first to second follow-up of the cohort showed no significant changes in physical or psychosocial functioning, pain, or fatigue. In study IV, physical ability and pain were significant predictors of the average variation of physical health while psychiatric distress and female gender were significant predictors of the average variation of mental health. Impaired physical health was associated with low rates of psychiatric distress. As compared to the general Norwegian population, impaired HRQL in the physical domain was found, but not in the mental domain, and a higher level of education, but similar employment rate. Conclusion: The four studies demonstrate complementary findings. Discrepancies between interviews and inquiries indicate that the interviews illuminate a depth and breadth of life with JIA in a life-span perspective that not is possible to unveil solely by standardised inquiries. Although persistent favourable outcomes are found physically and psychosocially from first to second follow-up, young adults with JIA reveal that life with JIA encompasses struggle and adjustment to an insecure life situation physically, psychologically, and socially. / Bakgrunn og mål: Mange års erfaring som pediatrisk sykepleier har vist meg at unge mennesker med kroniske barnesykdommer faller mellom to stoler i overgangen til voksent liv. Internasjonale studier støtter denne erfaringen, og norske ungdommer med juvenil idiopatisk artritt er ikke noe unntak. Kronisk barneleddgikt kan ha vidtrekkende konsekvenser for barnets vekst og utvikling, for familien og samfunnet for øvrig. Det faktum at mange barn fortsetter å ha aktiv sykdom og senvirkninger av sykdommen gjennom ungdomsårene og inn i voksent liv, understreker betydningen av å belyse de unges helse og livssituasjon i et folkehelseperspektiv. Gjennom denne avhandlingen ønsker jeg å undersøke fysisk, psykisk og sosial helse blant unge voksne med barneleddgikt i et livsløpsperspektiv. Metode: Avhandlingen har en kvantitativ og en kvalitativ tilnærming. Studie I hadde en abduktiv eksplorerende design. Gjennom fokusgruppeintervjuer med respektivt unge mennesker med barneleddgikt og helsepersonell innen revmatologi ble opplevelser og erfaringer med overgangen til voksenhelsetjenesten undersøkt. Kvalitativ innholdsanalyse ble benyttet. Studie II hadde også en abduktiv eksplorerende design med kvalitative intervjuer for å utforske livet med barneleddgikt blant unge voksne i et livsløpsperspektiv. Kvalitativ innholdsanalyse ble benyttet også her. Studie III hadde en longitudinell deduktiv design. Standardiserte spørreskjemaer om fysisk funksjon (Health Assessment Questionnaire), psykososial helse (General Health Questionnaire versjon 30), og sykdomsfølelse, smerte og trøtthet (Visual Analogue Scales) ble anvendt for å undersøke selvvurdert helse blant kohorten 18.3 år etter symptomdebut. Sammenligning med baselinestudien og første oppfølging ble gjort. Deskriptiv statistikk og non parametriske tester ble benyttet i dataanalysen. Studie IV var en deduktiv tverrsnittsstudie. I tillegg til spørreskjemaene som ble benyttet i studie III, ble spørreskjemaet SF-36 Health Survey benyttet for å undersøke selvvurdert helserelatert livskvalitet. Data fra telefonintervjuet om utdanning, yrkesaktivitet, behov for hjelpemidler på jobb, og behov for helsetjenester siste året ble inkludert. Sammenligninger ble gjort med norske normdata. Deskriptiv statistikk, parametriske og non parametriske tester ble benyttet i dataanalysen. Funn: Studie I viste at det å være i stand til å leve et meningsfylt og ansvarsbevisst voksenliv var et felles mål. Hindringer for de unge viste seg å være sykdommens natur, manglende fokus på overgangsprosessen, og overbeskyttende foreldre og helsepersonell. Hindringer blant helsepersonell var mangel på formelt samarbeid og omforent praksis på tvers av profesjoner og institusjoner, og mangel på kompetanse om ungdoms helse og utvikling. Studie II viste at livet med barneleddgikt innebærer en konstant veksling mellom kamp og tilpasning til et usikkert dagligliv og et uforutsigbart livsløp. Dette kom til uttrykk i erfaringer om kroppslige begrensninger eller frihet, interpersonlige opplevelser av å bli inkludert eller satt til side, og intrapersonlige opplevelser av usikkerhet eller trygghet. Blant de 55 unge voksne med barneleddgikt i studie III rapporterte 21 fysiske funksjonshemninger og 12 psykiatrisk distress. Videre rapporterte 26 pasienter sykdomsfølelse, 27 smerter, og 33 trøtthet med en skåring på 10 eller mer på VAS-skalaene (0-100). Signifikante korrelasjoner ble funnet mellom fysisk funksjonshemning, smerter, sykdomsfølelse og trøtthet, og mellom psykiatrisk distress, smerter og trøtthet. Sammenligninger fra første til andre oppfølging av kohorten viste ingen signifikante endringer i fysisk eller psykisk funksjonsevne, smerter eller trøtthet. Studie IV viste at fysisk funksjons-hemning og smerter var signifikante prediktorer for den gjennomsnittlige variasjonen i fysisk helse, mens psykiatrisk distress og kvinnelig kjønn var signifikante prediktorer for den gjennomsnittlige variasjonen i mental helse. Sviktende fysisk helse var ikke assosiert med psykiatrisk distress. Sammenlignet med norske normdata fant vi sviktende helserelatert livskvalitet i det fysiske domene, men ikke i det mentale domene, og høyere utdanningsnivå, men ingen forskjell i yrkesaktivitet. Konklusjon: Funnene fra de fire delstudiene kompletterer hverandre. Diskrepansen mellom funnene fra intervjuene og spørreskjemaene belyser en bredde og dybde i opplevelsene avlivet med barneleddgikt som det ikke er mulig å avdekke bare gjennom bruk av standardiserte spørreskjemaer. Selv om funnene viser vedvarende positive utfall av sykdommen både fysisk og psykososialt fra første til andre oppfølging, viser unge mennesker med barneleddgikt at livet innebærer kamp og tilpasning til en usikker livssituasjon fysisk, psykisk og sosialt.

The impact of transportation concerning older adults is under scrutiny as the number of older adults is expected to significantly increase in the coming years. The World Health Organization (WHO) spearheaded a world wide initiative that sought to examine what contributed to an “age-friendly community” in both developed and underdeveloped nations. This paper examines, in particular, the role that transportation plays in relation and contribution to an “age-friendly” community in Saanich, British Columbia, as an addition to the WHO initiative. Focus groups were conducted to ensure that information received was the lived experience of the individual. Results suggested that transportation was more than the ability to operate a vehicle, but in the ability to move safely within an environment. Additional information provided by participants spoke to the necessity of increasing awareness of licensing systems and improvements that could be implemented to ensure safety for older adult drivers and the community.

O tempo de vida e o desenvolvimento foliar sempre foram questões que intrigaram a humanidade, para além da questão científica, há um interesse até mesmo estético, uma vez que as folhas senescentes do hemisfério Norte e algumas do hemisfério Sul mudam sua coloração de verde para vermelho ou para um amarelo vistoso. Do ponto de vista científico o tempo de vida foliar está associado à produtividade das plantas, bem como às características estruturais das folhas. No entanto, a maioria dos trabalhos enfoca apenas a folha individualmente e não aborda o ponto que o tempo de vida foliar é, na verdade, um produto das taxas de nascimento e de mortalidade que ocorrem no nível da copa. Este é provavelmente o fator que faz com que haja um grande contraste na literatura sobre o tempo de vida foliar. Do ponto de vista ecológico analisam-se apenas as consequências do tempo de vida foliar, sem levar em consideração os mecanismos fisiológicos responsáveis pela mortalidade. Os trabalhos fisiológicos, por outro lado, enfocam em causas da mortalidade - o aumento na quantidade de hexoses e/ou mudanças nos reguladores de crescimento - sem levar em consideração as conseqüências do tempo de vida foliar. Este trabalho visa integrar estas duas visões. Como o nitrogênio é um dos minerais que possuem um efeito profundo no tempo de vida foliar, este foi usado como ferramenta para modificar o tempo de vida foliar de plantas de Senna alata, uma planta pioneira da família Leguminosae, que apresenta crescimento rápido. Foram realizados dois experimentos. No primeiro foi definida a melhor fonte de nitrogênio para o desenvolvimento da planta usando concentrações iguais de NO3, NH4 e NH4NO3. E no segundo experimento foi estudado o efeito de diferentes concentrações da melhor fonte. Em ambos os casos, a expansão, a biomassa, a fotossíntese (somente no segundo experimento) e teores e composição de carboidratos não estruturais, foram acompanhados para cada folha da planta. No primeiro experimento observou-se que ocorreu um aumento na taxa de mortalidade sem efeito na taxa de iniciação foliar, este fato levou a uma diminuição na longevidade das folhas, o que diminuiu o número de folhas na copa, mas não alterou a estrutura vertical da copa. A quantidade de hexoses na fase de senescência parece estar envolvida com o aumento na taxa de mortalidade através do mecanismo sensor de açúcares e como atuou diminuindo o tempo de senescência das folhas, levou a uma mudança no desenvolvimento foliar. No segundo experimento não houve diferença na mortalidade, mas um aumento na iniciação foliar, assim, conforme a concentração de nitrogênio aumentou, a longevidade das folhas tendeu a aumentar e o número de folhas na copa aumentou, mudando a estrutura vertical desta. Como obervado no primeiro experimento, a baixa concentração de hexoses durante a fase de maturidade pareceu ser o mecanismo que impediu a senescência foliar e que, portanto, modificou o desenvolvimento foliar por aumentar a sua fase de maturidade / Leaf life and development have always been intriguing aspects of nature. Even beyond the scientific scope, the aesthetics of such natural processes, illustrated in many different cases, such as when senescent northern hemisphere leaves (as well as some leaves found in the southern hemisphere) change colors from Green to re dor bright yellow. From a scientific standpoint, leaf life span is related to the plants′ productivity, as well as the structural characteristics of the leave themselves. Unfortunately, most current academic studies focus specifically on leaves, neglecting the fact that leaf life span is intimately related to birth and mortality rates at the canopy. This is possibly the greatest issue surrounding academic controversies and discussions regarding leaf life span. From na ecologic perspective, only the consequences deriving from leaf life are analyzed, while all mortality-related physiological mechanisms are not considered. Physiological studies, on the other hand, focus on causes of mortality - increased amount of hexoses and/or changes in growth regulators - but fail to consider the consequences of leaf life span. This article attempts to integrate both standpoints. As one of the minerals with greatest effect on leaf life span, nitrogen Will be used as a way to alter leaf life span during the experiments. In the first experiment we Will establish the most adequate nitrogen source, using the same NO3, NH4 and NH4NO3 concentrations. In the second experiment, we Will assess the effect of different concentrations in such nitrogen source. The first experiment indicated na increase in the mortality rate with no impact over the leaf initiation process, which decreased leaf life span and the amount of leaves in the canopy, but did not change the canopy vertical structure. The amount of hexoses in the senescence phase is responsible for the mortality rate increase and, by shortening the leaves′ senescence process, ultimately changed the leaves′ development. The second experiment did not indicate changes in the mortality rate, but prompted the leaf initiation process. Therefore, as the nitrogen concentratio increased, so did the leaves′ life span and the amount of leaves in the canopy, altering its vertical structure. During the maturity phase, the low hexose concentration seemed to be the mecanism responsible for hidering the leaf senescence process and, therefore, modified the leaves′ development by the increasing the maturity phase.

Cette thèse concerne l’étude qualitative (existence locale, existence globale, explosion en temps fini) de quelques équations de Schrödinger non-linéaires non-locales. Dans le cas où les solutions explosent en temps fini, l’estimation du temps maximal d’existence des solutions sera présentée. Le chapitre 1 concerne l’étude d’une équation de Schrödinger non-linéaire sur RN. On s’intéresse à l’existence locale d’une solution pour toute condition initiale donnée dans L2(RN). De plus, on montre que la norme-L2 de la solution explose en temps fini T < 1. Les démonstrations reposent essentiellement sur le théorème de point fixe de Banach et les estimations de Strichartz, et aussi sur le choix convenable de la fonction test dans la formulation faible du problème. Dans le chapitre 2, on considère une équation de Schrödinger non-linéaire non-locale en temps, et on démontre que les solutions de notre problème explosent en temps fini ; ensuite on obtient des conditions nécessaires d’existence globale. Finalement, on obtient une borne inférieure du temps maximal d’existence de la solution. Le chapitre 3 porte sur la non-existence de solutions d’une équation de Schrödinger non-linéaire posée dans RN. Dans un premier temps, sous certaines conditions sur la donnée initiale, on montre qu’il n’existe pas de solution faible globale ; puis on donne une estimation du temps maximal d’existence de la solution. Enfin, on établit des conditions d’existence locale, ou globale de l’équation considérée. En plus, on généralise les résultats précédents au cas d’un système 2 _ 2. Le dernier chapitre traite une équation de Schrödinger non-linéaire non-locale en temps sur le groupe de Heisenberg H. En utilisant la méthode de la fonction test, on démontre que l’équation n’admet pas de solution faible globale. De plus, on obtient, sous certaines conditions sur les données initiales, une estimation inférieure du temps maximal d’existence de la solution. / Our objective in this thesis is to study the existence of local solutions, existence global and blow up of solutions at a finite time to some nonlinear nonlocal Schrödinger equations. In the case when a solution blows-up at a finite time T < 1, we obtain an upper estimate of the life span of solutions. In the first chapter, we consider a nonlinear Schrödinger equation on RN. We first prove local existence of solution for any initial condition in L2 space. Then we prove nonexistence of a nontrivial global weak solution. Furthermore, we prove that the L2-norm of the local intime L2-solution blows up at a finite time. The second chapter is dedicated to study an initial value problem for the nonlocal intime nonlinear Schrödinger equation. Using the test function method, we derive a blow-up result. Then based on integral inequalities, we estimate the life span of blowing-up solutions. In the chapter 3, we prove nonexistence result of a space higher-order nonlinear Schrödinger equation. Then, we obtain an upper bound of the life span of solutions. Furthermore, the necessary conditions for the existence of local or global solutions are provided. Next, we extend our results to the 2 _ 2-system. Our method of proof rests on a judicious choice of the test function in the weak formulation of the equation. Finally, we consider a nonlinear nonlocal in time Schrödinger equation on the Heisenberg group. We prove nonexistence of non-trivial global weak solution of our problem. Furthermore, we give an upper bound of the life span of blowing up solutions.

Emotional Intelligence (EI) has been relatively unstudied after young adulthood. Yet there are a variety of reasons to expect that EI may be different at mid life than in young adulthood. Normative life experiences may lead to increases in EI, and as the array of different environments and experiences increases with age, one might expect greater individual differences in EI. Similarly, if EI is located somewhere at the intersection of personality and intelligence, as some have speculated, it may follow a course of structural differentiation similar to cognitive abilities. EI may be more closely linked to social variables such as loneliness and friendships at mid life, and its relation to established personality and ability factors such as the Big Five (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness) and fluid and crystallized abilities may also vary with age. These hypotheses were investigated in samples of 292 young adults and 246 mid life adults, using the Schutte Self Report Emotional Intelligence Inventory, the NEO-Five Factor Personality Inventory, markers of crystallized and fluid ability from Horn's Crystallized/Fluid Sampler, and a variety of other measures. Mid life adults scored higher on overall EI scores, but evidenced no greater range of individual differences than did young adults. A series of exploratory and confirmatory factor analyses revealed no greater differentiation in the mid life sample either among dimensions of EI or between EI and personality and intelligence variables. Finally, EI appeared equally predictive of social variables in each sample. Results are discussed from the perspective of lifespan and aging literature on emotion, personality, and social functioning. Qualifications for the inference of age-related change in cross sectional designs are considered, along with advantages and disadvantages of factor-analytic and covariance structure modeling methodology. Implications, particularly for psychotherapy with each age group, are discussed.

Differences in the composition of cell membranes are considered to be the physiological mechanism responsible for different metabolic rates, life span and consequently, different life-histories. The membrane pacemaker theory suggests that higher membrane unsaturation may be an important factor responsible for higher metabolic rate and shorter life span of organisms. The alternative hypothesis, on the other hand, assumes that membranes can function as structural antioxidants, and thus that higher membrane unsaturation may be associated with longer life span. The aim of this work was to test how changes in the fatty acid composition of membranes depends on body size, latitude and altitude, within which different life-histories and metabolic rate were observed. Temperate and tropical lowland songbird species were chosen for the models testing the effect of latitude, and only tropical species of songbirds were chosen for the models testing the effect of altitude. Part of the work was molecular sex determination. Using gas chromatography and mass spectrometry, the amount of individual fatty acids contained in red blood cell phospholipids was obtained from blood samples. The results showed that the composition of the membranes in most cases correlates with body size, which also correlates with almost all...