Tesis sobre el tema "Clinal variation"
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Holman, James y n/a. "Clines, Species and Eucalypts: An Evolutionary Perspective". Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030527.124144.
Texto completoHolman, James. "Clines, Species and Eucalypts: An Evolutionary Perspective". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/365394.
Texto completoThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
Full Text
Dickens, Jeremy Kenneth. "Taxonomy of Trogon rufus (Gmelin, 1788) and Amazonian ring-shaped clinal variation". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/38/38131/tde-15022016-164253/.
Texto completoNós revisamos a taxonomia do complexo Trogon rufus sob o conceito Biológico de Espécies. Unidades taxonômicas possíveis, quebras e zonas de transição taxonômicas foram definidas usando mapas de calor e isofenas (linhas de contorno de fenótípo) baseados em caráteres de cor, barramento e morfometria. Esses possíveis táxons foram testados pelas análises de discriminantes. Dados de coloração foram obtidos por meio de espectrometria, e os padrões de barramento por meio de fotos de alta qualidade. Nós encontramos quatro espécies biológicas distintas Trogon chrysochloros Pelzeln 1856, da Mata Atlântica, diagnosticável pelo barramento mais escuro e denso na face inferior da cauda e coberteiras da asa, maior tamanho corpóreo, canto mais rápido, com mais notas e de frequência mais alta. Suas partes superiores (cabeça, dorso e cauda) variam de azul a verde acobreado com o aumento da altitude. O bico também é relativamente menor e mais serrilhado, o que está ligado a uma dieta que consiste quase exclusivamente de grandes artrópodes, fazendo desta espécie o Trogon mais insetívoro do mundo, o que deve ser a razão de sua relativa raridade quando comparado a outros Trogonidae com os quais vive em simpatia. Trogon tenellus Cabanis 1862, da América Central, e Trogon cupreicauda Chapman 1914, do Chocó-Magdalena, formam um caso clássico de espécies biológicas, entrando em contato no extremo noroeste da província de Chocó, na Colômbia, sem a presença de formas intermediárias. T. tenellus é identificável pela face superior da cauda azul ou azul esverdeado, anel perioftálmico azul ou cinza, tarso cinza, e voz com de 2 a 4 notas, maior duração das notas e maior mudança entre frequência de pico e frequência alta entre a nota introdutória e nota principal. Essas características contrastam com a cor verde-oliva brilhante da face superior da cauda, anel perioftámico amarelo, tarso geralmente oliva, presença de marrom claro na face inferior da cauda das fêmeas e canto com entre 6 e 8 notas, de menor duração, pouca mudança na frequência entre a primeira nota e o canto principal de T. cupreicauda. Este varia clinalmente de azul para uma plumagem mais verde acobreada e de barramento preto mais espesso para mais fino em uma gradiente da costa do Pacífico, do noroeste do Equador até o Vale do Magdalena. A maior distinção de estados de caráter relativa a T. tenellus na região onde os dois grupos se encontram provê uma possível evidência de deslocamento de caracteres como resultado de exclusão competitiva entre estas duas espécies, mantendo suas distribuições parapátricas. A população amazônica pertence a única espécie biológica Trogon rufus Gmelin 1788, mas com duas formas altamente distintas que designamos como Trogon rufus rufus do Escudo Guianense, e Trogon rufus sulphureus no sul e oeste da Amazônia, com a qual amazonicus de Todd é sinonimizada. Estas são morfologicamente, e em menor escala, vocalmente distintas nas duas margens do baixo Rio Negro e áreas abertas e/ou montanhosas da bacia do Rio Branco, mas apresentam troca de caracteres limitada nas longitudes entre 52 e 58 Oeste na margem sul do Rio Amazonas, centrado nos arredores do Rio Arapiuns, na margem esquerda da foz do Tapajós. Nós postulamos que isto é um resultado de contato secundário, como consequência de mudanças no curso principal do Rio Amazonas em tempos de níveis mais baixos do mar durante o Plio-Pleistoceno. T. r. sulphureus é identificado pela coloração tipicamente acobreada da face superior da cauda com uma banda sub-terminal de tonalidade esverdeada, anel perioftálmico amarelo, barras negras espessas e de baixa densidade na face inferior da cauda e nas coberteiras das asas e pela ausência de uma faixa peitoral. Em certos casos eles também podem ser distinguíveis pela voz com uma nota introdutória de maior frequência e/ou uma modulação descendente mais pronunciada no canto principal. Este grupo varia clinalmente em gradiente de oeste para leste, de uma coloração cobre forte até verde oliva na face superior da cauda com faixa sub-terminal mais ou menos distinta, anel perioftálmico azul, presença ou ausência de uma faixa peitoral branca e barramento na face inferior da cauda e coberteiras de menor espessura e, consequentemente, maior densidade. Nossos dados apontam que estes caracteres mudam linearmente entre sulphureus e rufus de acordo com a distância ao longo de uma gradiente clinal em forma de laço do Oeste Amazônico até o Escudo das Guianas, conectado pela zona de contato de Arapiuns, sugerindo isolamento por distância. Isto sugere um remanescente de um padrão de espécie em anel. Além disso, dois espécimes com possível mistura de caracteres foram de fato encontrados no alto Rio Negro e Pantepui, onde se espera que T. r. rufus e T. r. sulphureus entrem em contato, fechando o anel efetivamente. Ainda é necessário testar se Trogon rufus constitui uma espécie em anel válida, preferencialmente usando dados moleculares, mas este caso ilustra claramente que a distinção entre variação clinal e espécie em anel é uma questão de grau e não de tipo, com a formação de espécie em anel necessariamente passando por um estágio clinal sem sobreposição entre os grupos terminais. Nós assim sugerimos o conceito de espécie em laço, onde as formas terminais não se sobrepõem, mas são ligadas através de uma série de populações onde há fluxo gênico. Parece provável que estes padrões são mais amplamente distribuídos na Amazônia do que é sabido atualmente devido a uma propensão à variação clinal e especiação parapátrica causada por sua grande extensão geográfica e abundância de barreiras geográficas semipermeáveis. Em relação a população do Centro de Endemismo Pernambuco, os poucos registros sugerem que esta é uma unidade taxonômica válida. Este grupo apresenta uma combinação única de canto muito similar ao de T. r. sulphureus, devido à alta frequência da nota introdutória e pronunciada modulação descendente ao longo do canto principal, com uma maior amplitude da frequência, combinada a maior tamanho, bico serrilhado, e anel perioftálmico azul, mas isso requer confirmação. Este caso demanda atenção urgente, já que a população remanescente é muito pequena e de distribuição restrita ao município de Murici, em Alagoas.
Kivelä, S. M. (Sami Mikael). "Evolution of insect life histories in relation to time constraints in seasonal environments:polymorphism and clinal variation". Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514293788.
Texto completoTiivistelmä Hyönteisten kasvu ja kehitys ovat pääsääntöisesti mahdollisia vain kesän aikana. Etelään päin mentäessä kesä pitenee, ja saman kesän aikana kehittyvien hyönteissukupolvien määrä kasvaa. Kesän pituus aiheuttaa lisääntymiseen ja toukkien kasvuun kohdistuvan aikarajoitteen, joka heikkenee etelään päin siirryttäessä. Aikarajoite kuitenkin tiukkenee siellä, missä yksi uusi sukupolvi ehtii juuri kehittymään saman kesän aikana, sillä kesä on nyt jaettava useamman sukupolven kesken. Väitöstyössä tarkastelin hyönteisten elinkierto-ominaisuuksien evoluutiota suhteessa aikarajoitteisiin sekä diskreetin että jatkuvan muuntelun näkökulmista. Diskreettiä muuntelua tutkin lanttuperhosella (Pieris napi), jolla esiintyy diskreettejä elinkiertostrategioita. Kokeellisesti osoitin, että toukkien välinen kilpailu on epäsymmetristä, mikä yhdessä eri elinkiertostrategioiden erilaisen lisääntymisen ajoittumisen kanssa voi ylläpitää diskreettiä muuntelua. Simulaatiomalli osoitti, että erilaiset elinkiertostrategiat voivat säilyä populaatiossa pelkästään niiden erilaisen lisääntymisen ajoittumisen ansiosta. Elinkierto-ominaisuuksien jatkuvaa muuntelua tutkin neljän mittariperhosen (Cabera exanthemata, Cabera pusaria, Chiasmia clathrata ja Lomaspilis marginata) avulla ja teoreettisesti yleisellä tasolla. Aikaisempi teoria ennustaa ruumiinkoon ja kehitysajan muuntelevan sahalaitakuvion mukaisesti siirryttäessä pohjoisesta etelään, koska aikarajoitteet muuntelevat samalla tavalla. Tämä teoria perustunee epärealistisiin oletuksiin, koska kokeelliset tulokset eivät tukeneet teoriaa silloinkaan, kun mittariperhosten ruumiinkoko muunteli ennustetulla tavalla. Teoreettinen tutkimus osoitti, että myös lisääntymispanostuksen tulisi muunnella sahalaitakuvion mukaisesti suhteessa kesän pituuteen siten, että se on korkeimmillaan siellä, missä aikarajoitteet ovat tiukat. Mittariperhosten tutkiminen antoi jossain määrin tukea tälle ennusteelle. Tulosten perusteella jatkuvaa maantieteellistä muuntelua ennustetaan elinkierto-ominaisuuksille, jotka muuntelevat jatkuvalla asteikolla. Erilaiset elinkiertostrategiat voivat sen sijaan säilyä populaatiossa, jos elinkierto-ominaisuuksien muuntelu on diskreettiä. Eri ominaisuuksien monimutkaiset vuorovaikutukset sekä eri sukupolvien mahdollisesti kokemat erilaiset aikarajoitteet olisi syytä tuntea, kun tarkastelun kohteena on yksittäisen ominaisuuden evoluutio
Lobo, Nina L. "Clinal variation at putatively adaptive polymorphisms in mature populations of Sitka spruce (Picea sitchensis (Bong.) Carr.)". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/34558.
Texto completoChen, Jun. "Conifer Evolution, from Demography and Local Adaptation to Evolutionary Rates : Examples from the Picea genus". Doctoral thesis, Uppsala universitet, Växtekologi och evolution, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177482.
Texto completoSpeer, William D. "Systematics of Eastern North American Bracken Fern". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36715.
Texto completoMaster of Science
Olsson, Jenny. "Genetic diversity and hardiness in Scots pine from Scandinavia to Russia". Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160222.
Texto completoLovat, Christie-Anna. "Clinal variation and phenology in two conspecifics of Phragmites australis (Cav.) Trin. Ex Steud in Northeastern North America: implications for current management and future climate change". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119468.
Texto completoLa reproduction sexuée et la production subséquente de graines viables peuvent faciliter la dispersion d'espèces végétales indigènes ou non indigènes/envahissantes dans de nouvelles régions ainsi que possiblement une adaptation rapide à des conditions changeantes grâce à la sélection de phénotypes appropriés. Le succès de la reproduction sexuée pour de nombreuses espèces végétales a été lié à une accumulation critique de degrés-jours de croissance (DJCs) durant la saison. Cependant les DJCs sont souvent limités dans les climats nordiques. Avec les changements climatiques et les températures qui augmenteront particulièrement vers le nord, le DJCs sont susceptibles d'augmenter et des espèces actuellement limitées par un manque de DJCs pourraient voir une augmentation de leur reproduction sexuée et éventuellement une extension de leur aire de répartition. Un suivi sur le terrain et des essais de germination ont été utilisés pour tester la relation entre les DJCs saisonniers et le développement, la hauteur et la reproduction sexuée d'une espèce envahissante non indigène, Phragmites australis (Cav.) Trin. Ex Steud. (M haplotype) et sa congénère indigène, P. australis subsp. americanus. Durant la saison 2012, 29 populations ont été suivies dans cinq isothermes le long d'un gradient latitudinal de 1000 km du New Jersey (États-Unis) à Alma (Québec). Le P. australis non indigène était en moyenne plus court, requerrait moins de DJCs pour produire des inflorescences, et produisait moins de graines viables avec une diminution des DJCs saisonniers. Pour un même isotherme, le P. australis indigène était plus court et se développait plus tôt que le P. australis non indigène, et aussi généralement produisait plus de graines. Globalement, la réponse du P. australis indigène n'était pas liée au DJCs saisonniers. Le long du gradient climatique de la zone étudiée, il semble que le manque de DJCs limite actuellement l'expansion par dispersion de graines du P. australis non indigène, tout en ayant peu ou pas d'effet sur le P. australis indigène. Une production de graines accrue par les changements climatiques pourrait permettre au P. australis envahissant d'exploiter des niches climatiques nouvellement disponibles.
Olsson, Katarina. "Population differentiation in Lythrum salicaria along a latitudinal gradient". Doctoral thesis, Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-364.
Texto completoNymark, Marianne Kristine. "Taxonomy of the Rufous-naped lark (Mirafra africana) complex based on song analysis". Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-435322.
Texto completoSghaier, Maissa. "Clinical-task based reconstruction in Digital Breast Tomosynthesis". Electronic Thesis or Diss., université Paris-Saclay, 2020. http://www.theses.fr/2020UPASG040.
Texto completoThe reconstruction of a volumetric image from Digital Breast Tomosynthesis (DBT)measurements is an ill-posed inverse problem, for which existing iterative regularizedapproaches can provide a good solution. However, the clinical task is somehow omittedin the derivation of those techniques, although it plays a primary role in the radiologistdiagnosis. In this work, we address this issue by introducing a novel variational formulationfor DBT reconstruction. Our approach is tailored for a specific clinical task, namely the detection of microcalcifications. Our method aims at simultaneously enhancing the detectionperformance and enabling a high-quality restoration of the background breast tissues.First, we propose an original approach aiming at enhancing the detectability of microcalcifications in DBT reconstruction. Thus, we formulate a detectability function inspired from mathematical model observers. Then, we integrate it in a cost function which is minimized for 3D reconstruction of DBT volumes. Experimental results demonstrate the interest of our approach in terms of microcalcification detectability.In a second part, we introduce the Spatially Adaptive Total Variation (SATV) as a new regularization strategy applied to DBT reconstruction, in addition to the detectability function. Hence, an original formulation for the weighted gradient field is introduced, that efficiently incorporates prior knowledge on the location of small objects. Then, we derive our SATV regularization, and incorporate it in our proposed 3D reconstruction approach for DBT. We carry out several experiments, in which SATV regularizer shows a promising improvement with respect to state-of-the-art regularization methods.Third, we investigate the application of Majorize Minimize Memory Gradient (3MG) algorithm to our proposed reconstruction approach. Thus, we suggest two numerical improvements to boost the speed of the reconstruction scheme. Then, we assess the numerical performance of 3MG by comparing the convergence speed of the proposed method with state-of-the-art convex optimization algorithms.The last part of this thesis is focused on the quantitative assessment of the contribution of our proposed DBT reconstruction. Thus, we conduct a visual experiment trial involving fourteen readers including nine radiologists with different levels of expertise and five GE Healthcare experts in mammography. According to specific visual criteria, the results show the outperformance of our proposed reconstruction approach over the standard non-regularized least squares solution
Menon, Muralee. "Addressing unwarranted variation in clinical cancer practice". Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:6ca56f0c-ad72-40b9-8eea-e5829c185a1f.
Texto completoRysavy, Matthew Albert. "Prognosis and variation in perinatal epidemiology". Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/5619.
Texto completoChang, Tien-yew Josiah y 張添佑. "Clinical trial laboratory services: industry demands and cost variation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B42685527.
Texto completoCardno, Alastair George. "The quantitative genetics of clinical variation in psychotic illnesses". Thesis, Cardiff University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394591.
Texto completoChang, Tien-yew Josiah. "Clinical trial laboratory services : industry demands and cost variation /". View the Table of Contents & Abstract, 2001. http://sunzi.lib.hku.hk/hkuto/record/4268552.
Texto completoIssa, Rahizan. "Genomic variation and gene expression of clinical isolates of Mycobacterium tuberculosis". Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1444795/.
Texto completoGow, Jason M. "Cellular and clinical effects of genetic variation in xenobiotic ABC transporters". Diss., Search in ProQuest Dissertations & Theses. UC Only, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3251937.
Texto completoHallier, Andrea Rae. "Variant-curation and database instantiation (Variant-CADI): an integrated software system for the automation of collection, annotation and management of variations in clinical genetic testing". Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/2218.
Texto completoTsampalieros, Anne. "Inter-centre Variation in the Management of Kidney Transplant Recipients and Its Impact on Clinical Outcomes". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37266.
Texto completoStulberg, Jonah James. "Variations in Adherence to Surgical Process Measures and Clinical Outcomes". Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1248214650.
Texto completoMorken, Gunnar. "Seasonal Variation of Human Mood and Behavior". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Medicine, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-326.
Texto completoSeasonal variations of mood, behavior and physiology have been of increasing interest. At least two different seasonal rhythms seem to exist: Descriptions of Seasonal Affective Disorder (SAD) with increased weight, increased sleep and fatigue during winter have attracted attention in academic psychiatry and in the general public the last two decades. In addition to such a difference in mood, weight and sleep between summer and winter, many studies describe a spring and fall increase in frequency of suicides and of admissions to hospital for mood disorders. In searching for a possible etiology for these seasonal changes, the main focus has been on variations in length of day.
The objective of this thesis was to study the existence and pattern of seasonal variation in some forms of behavior and of psychiatric illness among children and adults in Norway. Possible statistical connections between seasonal variations of behavior and changes in length of day and the influences of latitude, sex and age were also studied.
The monthly numbers of incidents in different groups were studied: All suicides in Norway 1969-96 (N=14.503), admissions to hospital for depression and mania in some hospitals 1992-96 (N=4.341), all violent episodes recorded by the police in Norway 1991-97 (N=82.537), all patient-staff incidents in a psychiatric department 1990-97 (N=502), all telephone calls to the Red Cross help-line for children and adolescents in Norway 1996-98 (N=691.787calls, 220.602 conversations) and in Trondheim, Norway 1991-97 (N=80.983 calls, 22.698 conversations) were included in the thesis. The monthly frequencies of these incidents were compared to an expected equal daily frequency of incidents through the year. Changes with increasing age and increasing latitude were examined. Correlations between the monthly frequencies of incidents and the length of day, with maximum impact at midsummer, and correlations between the monthly frequencies of incidents and the speed of change in length of day, with maximum impact at the equinoxes, were also studied.
In this thesis, an increased activity in April-June and in October-November is described for all the groups that were studied. In summer and winter there is less activity than in the rest of the year. Among children calling the help-line, a steady diminishing seasonal variation in number of calls with increasing age from 7 to 17 years of age and an increasing seasonal variation in number of calls with increasing latitude were found. Also the seasonal variation of violence increases with increasing latitude in Norway. Among men there is a correlation between the monthly number of suicides and the monthly number of admissions for mania and a correlation between the monthly number of suicides and the monthly number of admissions for depression. Among women there is a diminishing seasonal variation of admissions for depressions with increasing age. The monthly frequency of violence in Norway and the monthly frequency of calls to the Red Cross help-Line for children and adolescents correlated with a delay of 1-2 months with the monthly change in length of day with maximum impact at the equinoxes.
The results in the thesis correspond with earlier studies describing an increase in the frequency of suicides and an increase in admissions for depressions in spring and fall. A corresponding rhythm for other forms of human behavior is described in the present thesis, indicating that the seasonal rhythm of psychiatric illness reflects a seasonal rhythm of behavior in greater parts of the population. The seasonal variation in behavior seems to increase with increasing latitude, to be more dramatic in the northern than in the southern parts of Norway. In this thesis results supporting a hypothesis of human behavior being influenced by changes in length of day are given. Changes in length of day may induce changes in sleep and other disturbances in the daily rhythm that could change mood and other emotional qualities in vulnerable individuals. The demands on our capability to adapt to changes in length of day are largest at the equinoxes.
Årstidsvariasjon av sinnstemning og adferd.
Det er økende interesse for årstidsvariasjon av adferd og av forekomsten av psykiske lidelser. Det synes å foreligge minst to ulike årstidsrytmer i befolkningen; Størst oppmerksomhet har oppdagelsen av vinterdepresjon karakterisert ved tristhet, tretthet, økt vekt og forlenget søvn vakt. I tillegg til en slik forskjell i humør, vekt og søvn mellom sommer og vinter, er det en rekke beskrivelser av overhyppighet av selvmord og av innleggelser i sykehus for depresjoner vår og høst. Årsakene til disse to ulike årstidsrytmene er ikke kjent, men man har antatt at variasjon i dagslengde gjennom året spiller en rolle.
Hensikten med denne avhandlingen har vært å undersøke om det er årstidsvariasjon i forekomsten av ulike former for adferd og av psykiske lidelser hos barn og voksne i Norge. Videre er eventuelle statistiske sammenhenger mellom adferd og dagslengde gjennom året undersøkt. Til sist er forskjeller i årstidsrytme knyttet til breddegrad, alder og kjønn undersøkt.
Antallet hendelser pr måned i ulike grupper ble studert; Alle selvmord i Norge 1969-96 (N=14.503), innleggelser for depresjon og mani i en del sykehus 1992-96 (N=4.341), alle registrerte voldsepisoder i Norge 1991-97 (N= 82.537), personalskader i et psykiatrisk sykehus 1991-97 (N=502), alle telefoner til Røde Kors Kontakttelefon for barn og unge i Norge 1996–98 (N=691.787 oppringninger, 220.602 samtaler) og i Trondheim 1991-97 (N=80.983 oppringninger, 22.698 samtaler) ble inkludert i arbeidet. Hyppigheten av alle disse hendelsene i hver måned ble sammenlignet med en forventet lik fordeling av hendelsene året igjennom. Endringer med økende alder og med økende breddegrad ble undersøkt. Videre ble det gjort sammenligninger med dagslengde som er lengst ved sommersolverv og kortest ved vintersolverv, og sammenligninger med endringer av dagslengde som er hurtig ved vår og høstjamndøgn og sakte ved solvervene.
I alle disse materialene er det en økt aktivitet april – juni og oktober – november, videre er det stille perioder om vinteren og om sommeren. Blant barn som ringer kontakttelefonen er det gradvis avtagende årstidsvariasjon av henvendelser med økende alder fra 7 til 17 år og økende årstidsvariasjon i antallet henvendelser jo lenger nord man kommer i Norge. Også årstidsvariasjonen av vold i Norge endrer seg jo lengre nord man kommer i landet.
Blant menn er der en korrelasjon mellom det månedlige antallet av selvmord og av innleggelser for mani og mellom antallet selvmord og innleggelser for depresjon. Blant kvinner er det en avtagende årstidsvariasjon av innleggelser for depresjon med økende alder.
Den månedlige endring av dagslengde som er raskest ved jamndøgnene korrelerer med en viss forsinkelse med forekomsten av vold i Norge og med antallet oppringninger til Barn og Unges kontakttelefon.
Funnene i avhandlingen er i samsvar med tidligere beskrivelser av en markert økning av suicid og av innleggelser for depresjoner om våren og til dels om høsten. I avhandlingen er en tilsvarende rytme funnet for annen adferd. Dette tyder på at årstidsrytmen av psykiatrisk sykelighet avspeiler en årstidsrytme av adferd i store deler av befolkningen. Videre ser det ut til at forskjellene i adferd gjennom året blir mer markerte jo lengre nord man kommer i landet. I avhandlingen er det funn som støtter en hypotese om at endringer i dagslengde påvirker mennesket, det er mulig at dette skjer gjennom endret søvn og andre forstyrrelser i døgnrytmen. Vår døgnrytme er utsatt for størst krav til å tilpasse seg hurtige endringer i lysforhold rundt jamndøgnene.
Donguy, Jean Réné. "Contribution à la connaissance des variations climatiques de l'Océan pacifique tropical". Bordeaux 1, 1985. http://www.theses.fr/1985BOR10608.
Texto completoRoos, J. L. (Johannes Louw). "Genetic variation and clinical variables contributing to Schizophrenia in a Founder Population from South Africa". Thesis, University of Pretoria, 2014. http://hdl.handle.net/2263/44335.
Texto completoThesis (DSc)--University of Pretoria, 2014.
tm2015
Psychiatry
DSc
Unrestricted
Prause, Nicole. "Role of emotion and attention in variations in sexual desire". [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3278474.
Texto completoSource: Dissertation Abstracts International, Volume: 68-10, Section: B, page: 6979. Adviser: William P. Hetrick. Title from dissertation home page (viewed May 21, 2008).
Khumalo, Nokwanda. "Cultural variations in the presentation of depression in female patients at Valkenberg Hospital". Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/11646.
Texto completoDepression is a significant problem for both developed and developing countries. Local and international literature indicates that there are culturally mediated differences in presentation that contribute to more women being diagnosed with depression than men and to the predominance of particualar features of the illness in different settings. The aim of this archival study was to explore the presentation of depression across race groups in female patients at Valkenberg Hospital in the Western Cape. The narratives of patients' presenting complaints were obtained from the history taking notes in 46 hospital files, comprised of three sets of 15 files belonging to Black, White and Coloured patients, and one file belonging to a patient of Asian origin. Thematic analysis was used to analyze the narratives. Findings revealed that patients across race groups viewed depression as occurring in and resulting from interpersonal problems. However, White and Coloured patients also related their main problem to emotional distress, which was the main trigger for seeking help. Black patients reported difficulties in coping with life stressors as their main complaint, and frequently cited experiences of gender based violence. Distress seems to be tolerated until it manifests in behavioural disturbances. It was found that Black patients sought help only when their behaviour became distruptive for those around them. It was also observed that depression with psychotic featues and a co-morbid HIV diagnosis were reported most frequently among Black patients. There were thus similarities and differences in the presentation of depression across race groups. Patients' understandings of depression are mediated by various socio-cultural factors.
Du, Toit Francesca. "Circulus arteriosus cerebri: Anatomical variations and their correlation to cerebral aneurysms". Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/16481.
Texto completoThe anatomical structure of circulus arteriosus cerebri was first described by Thomas Willis in 1664. Many variations in the circulus arteriosus cerebri have since been reported. The extent to which anatomical variations within the circle influence aneurysm formation in a South African sample has not yet been established. The results of such a study would be of value to clinicians treating patients with vascular diseases. The aim of the study was to determine if there is a correlation between arterial variations in the circulus arteriosus cerebri and cerebral aneurysm formation. The brains of 39 cadavers at the Faculty of Health Sciences were removed and the circulus arteriosus dissected. In addition, 113 patients who underwent a MRI or MRA of the circulus arteriosus cerebri at the Department of Radiology at the Groote Schuur Hospital, Cape Town were included. For both of these samples the anatomical variations and any aneurysms present were documented. The external diameters of the arteries forming the circulus arteriosus cerebri were also measured. No aneurysms were found in the cadaver sample, thus the correlation could not be tested. In the sample of images from the 113 patients, 111 images showed one or more anatomical variation of the circulus arteriosus cerebri. Of these, 59 had one or more cerebral aneurysm and 52 had no aneurysms. Statistical analysis showed no significant correlation between cerebral aneurysms and anatomical variations in the circulus arteriosus cerebri for a South Africans ample. This is contradictory to what is seen in the literature. Further investigation is required to establish the reason why the results from this South African sample differ from the results reported in the international literature.
Zhen, Ying. "Natural variation in freezing tolerance in Arabidopsis thaliana". Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2165.
Texto completoBolt, Matthew A. "Evidence based assessment of the clinical impact of dose variations arising in the clinical radiotherapy dosimetry chain". Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/848888/.
Texto completoStewart, Michael John. "Dippers and non-dippers : potential causes and clinical significance of diurnal blood pressure variation". Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/26973.
Texto completoNguyen-Van, Do. "EBV gene variation and epigenetic alterations in Asian nasopharyngeal carcinoma and potential clinical applications /". Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-408-2/.
Texto completoAcar, Adrienne Ann. "Clinical relevance of sex and age relate variations in corpus callosum morphology". Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/65830.
Texto completoDissertation (MSc)--University of Pretoria, 2017.
Anatomy
MSc
Unrestricted
Stocks, Michael. "Neutral and Adaptive Processes Shaping Genetic Variation in Spruce Species". Doctoral thesis, Uppsala universitet, Växtekologi och evolution, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-207714.
Texto completoSim, Sarah C. "Genetically determined interindividual variation in cytochrome P450 dependent drug metabolism : molecular basis and clinical implications /". Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-060-2/.
Texto completoForsberg, Andreas. "Spatial variation of radio frequency magnetic field exposure from clinical pulse sequences in 1.5T MRI". Thesis, Umeå universitet, Institutionen för fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-90391.
Texto completoIrwin, Ryan. "Understanding variation in the clinical quality of primary care : a typology of general practice organisations". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7573/.
Texto completoOchola, Harold Martin Owino. "Using genomics and population genetics to understand genetic variation in Malawi Plasmodium falciparum clinical isolates". Thesis, University of Liverpool, 2013. http://livrepository.liverpool.ac.uk/15753/.
Texto completoShank, Jessica. "Topological Domain Variations Among Patients Undergoing Microarray Testing". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491308068052218.
Texto completoGoropashnaya, Anna. "Phylogeographic Structure and Genetic Variation in Formica Ants". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3803.
Texto completoBeukes, Philip Rudolph. "Variation in radiosensitivities of different individuals to high energy neutrons and 60Cobalt γ-rays". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71921.
Texto completoENGLISH ABSTRACT: Background: The assignment of radiation weighting factors to high energy neutron sources is important as there is reason to believe that neutron relative biological effectiveness (RBE) may be related to the inherent radiosensitivity of different individuals. A study was undertaken to quantify the inherent radiosensitivities of lymphocytes obtained from different donors to 60Co y-rays and p(66)/Be neutrons. For this a novel semi-automated image analysis process has been employed. In addition the responses of lymphocytes with different inherent radiosensitivities have also been tested using Auger electrons emitted by 123I. Methods: The RBE of neutrons was determined from dose-response curves for lymphocytes from different donors. Isolated T-lymphocytes irradiated in vitro were cultured to induce micronuclei in binucleated cells and micronuclei (MN) formations numerated using a semi-automated Metafer microscope system. The accuracy in obtaining dose response curves with this method has been tested by evaluating dispersion parameters of MN formations in the response to the different treatment modalities. Differences in the inherent radiosensitivities of cells from different donors were ascertained using 95 % confidence ellipses. [123I]Iododeoxyuridine was prepared in a formulation that allows incorporation of 123I into the DNA of lymphocytes. Micronucleus formations to this treatment were evaluated in lymphocytes with established differences in inherent radiosensitivities. Results: The image analysis system proved to be consistent in detecting micronuclei frequencies in binucleated lymphocytes. As a result, differences in the inherent radiosensitivities of different individuals were distinctive and could be stated at the 95% confidence level. The inter-individual radiosensitivity variations were considerably smaller for blood cells exposed to high energy neutrons compared to 60Co y-rays. Relative biological effectiveness (RBEM) values between 2 and 13 were determined that are highly correlated with the inherent radioresistance of lymphocytes obtained from different individuals. As such radiation weighting factors for high energy neutrons cannot be based on cytogenetic damage determined in lymphocytes from a single donor. Dispersion parameters for micronuclei formations proved to vary according to ionization density. The variation in RBE with neutron dose changed according to theoretical considerations and automated image analysis detection of MN is thus a suitable method to quantify radiation weighting factors. A clear reduction in the variation in radiosensitivity is noted for lymphocytes exposed to Auger electrons compared to 60Co y-rays. The effectiveness of Auger electrons from [123I]IUdR to induce biological damage is demonstrated as the number of disintegrations needed to yield micronuclei formations was found to be more than two orders of magnitude less than that of other compounds. An increase in the RBE of Auger electrons with radioresistance can be inferred from these findings and constitutes a basis for therapeutic gain in treating cells compared to using radioisotopes emitting low-LET radiation.
AFRIKAANSE OPSOMMING: Agtergrond: Die bepaling van straling gewigsfaktore vir hoë energie neutron bronne is belangrik, aangesien daar rede is om te glo dat die relatiewe biologiese effektiwiteit (RBE) kan verband hou met die inherente stralings sensitiwiteit van verskillende individue. Hierdie studie is onderneem om die inherente radiosensitiwiteit van limfosiete verkry vanaf verskillende skenkers te kwantifiseer na blootstelling aan 60Co y -strale en p(66)/Be neutrone. Vir hierdie doel is daar van 'n semi-outomatiese beeldontleding metode gebruik gemaak. Daarbenewens is die reaksie van limfosiete met vooraf bepaalde inherente radiosensitiwiteite ook getoets aan die hand van Auger elektrone wat uitgestraal word deur 123I. Metodiek: Die RBE van neutrone was bepaal uit dosis mikrokerne frekwensie verwantskappe verkry vir limfosiete. Geïsoleerde T-limfosiete was in vitro bestraal en gekweek om mikrokerne te vorm in dubbelkernige selle. Die mikrokerne was gekwantifiseer deur die gebruik van 'n semi-outomatiese Metafer mikroskoop stelsel. Die akkuraatheid in die verkryging van dosis-effek krommes met hierdie metode is getoets deur die ontleding van verspreidings parameters van MN vorming in reaksie op behandeling met die verskillende stralings modaliteite. Verskille in die inherente stralingsensitiwiteite van die selle van verskillende skenkers was vasgestel deur die konstruksie van 95 % betroubaarheidsinterval ellipse. [123I]Iododeoxyuridine was ook berei om 123I in die DNA van limfosiete in te bou. Die mikrokerne vorming op die behandeling is beoordeel in limfosiete met gevestigde verskille in inherent radiosensitiwiteite. Resultate: Die beeld analise stelsel bewys om konsekwent te wees in die opsporing van mikrokerne wat vorm in dubbelkernige limfosiete. Verskille in die inherente radiosensitiwiteite van verskillende skenkers kon vasgestel word op die 95 % betroubaarheidsvlak. Die skommeling in inter-individuele stralings sensitiwiteite was kleiner vir bloed selle blootgestel aan hoë-energie neutrone in vergelyking met 60Co y-strale. Relatiewe biologiese effektiwiteit (RBEM) waardes tussen 2 en 13 is bepaal wat sterk verband hou met die inherente radioweerstandbiedendheid van limfosiete verkry vanaf verskillende persone. As sodanig kan straling gewigsfaktore vir hoë energie neutrone nie gebaseer word op sitogenetiese skade in limfosiete van 'n enkele skenker nie. Verspreidings parameters vir mikrokern vorming het gewissel as ‘n funksie van ionisasiedigtheid van die straling. Die verandering in RBE met neutron dosis verloop volgens teoretiese oorwegings en die semi-outomatiese beeldontledings metode om mikrokerne op te spoor is dus geskik om stralings gewigsfaktore te kwantifiseer. 'n Duidelike afname in die verandering in die stralingsensitiwiteite is waargeneem vir limfosiete blootgestel aan Auger elektrone in vergelyking met 60Co y-strale. Die hoë doeltreffendheid van Auger elektrone afkomstig van [123I]IUdR om biologiese skade te veroorsaak, word weerspieël deur die feit dat die getal disintegrasies wat nodig is om mikrokerne te vorm meer as twee ordes grootte minder is as dié van ander verbindings. 'n Toename in die RBE van Auger elektrone in selle wat radioweerstandbiedend is kan afgelei word uit hierdie bevindinge. Dit vorm 'n basis vir terapeutiese wins in die behandeling van selle in vergelyking met die gebruik van radio-isotope wat lae ionisasie digthede tot stand bring.
Kampira, Elizabeth. "Pharmacogenetics of stavundine : role of genetic variation in mitochondrial DNA and polymerase gamma among adult Malawian HIV/AIDS patients". Doctoral thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/3168.
Texto completoIncludes bibliographical references.
Infectious diseases are endemic in Africa, especially tuberculosis (TB), malaria and human immunodefiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). Genomics research has the potential to improve the health of Africans through identification of genetic markers associated with either disease susceptibility or therapeutic drug response. This project was set to investigate the genetic correlates for drugs associated with mitochondrial toxicity that are used as part of HIV therapy, especially nucleoside reverse transcriptase inhibitors (NRTIs). Toxicity from NRTIs manifests through metabolic diseases such as peripheral neuropathy, lipodystrophy, lactic acidosis and hyperlactatemia but show interpatient variability. Studying African populations is likely to open the door for the population to benefit from novel diagnostic tools and drugs developed on the basis of pharmacogenomics knowledge. In an effort to contribute to this knowledge, the role of variation in mitochondrial DNA (mtDNA) and polymerase gamma (POL-γ) on how patients respond to stavudine-containing antiretroviral therapy (ART) among adult Malawian HIV/AIDS patients was investigated.
Nishihara, Mitsuhiro. "Investigation of Drug Metabolism by Non-Cytochrome P450 Enzymes and Its Clinical Relevance". Kyoto University, 2014. http://hdl.handle.net/2433/189328.
Texto completoMolinero, Vargas Juan Carlos. "Etude de la variabilité des abondances des copépodes planctoniques en Méditerranée, mécanismes et échelles caractéristiques : le cas de Centropages typicus". Paris 6, 2003. http://www.theses.fr/2003PA066227.
Texto completoGamieldien, Mohamed Y. "The retromolar foramen in the South African population : prevalence, structure and clinical significance of an anatomical variation". Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/45964.
Texto completoDissertation (MSc)--University of Pretoria, 2014.
tm2015
Anatomy
MSc
Unrestricted
Hawkins, Anna Elizabeth. "The detection and analysis of hepatitis B virus genome variation and its use in clinical studies". Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243553.
Texto completoCheeran, B. J. "Stimulation genomics : probing the effects of genetic variation on human cortical plasticity and its clinical implications". Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1335713/.
Texto completoBos, Antoine. "Natural variation in cold adaptation and freezing tolerance in Arabidopsis thaliana". Doctoral thesis, Umeå : Department of Ecology and Environmental Science, Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1947.
Texto completoClaes, Anthony N. J. "ANTI-MÜLLERIAN HORMONE IN STALLIONS AND MARES: PHYSIOLOGICAL VARIATIONS, CLINICAL APPLICATIONS, AND MOLECULAR ASPECTS". UKnowledge, 2014. http://uknowledge.uky.edu/gluck_etds/18.
Texto completoPicon, Laurence. "Utilisation de l'imagerie meteosat pour l'etude des variations a court terme du climat africain". Paris 6, 1991. http://www.theses.fr/1991PA066669.
Texto completo