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Visar resultat 21 - 25 av 25 avhandlingar som matchar ovanstående sökkriterier.

1. 21. Constructing a timetable of autumn senescence in aspen

   Författare :Johanna Keskitalo; Stefan Jansson; Howard Thomas; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Populus tremula; autumn senescence; senescence-associated genes; cellular timetable; transcriptional timetable; cDNA microarrays; EST sequencing; Plant physiology; Växtfysiologi;

   Sammanfattning : During the development and lifecycle of multicellular organisms, cells have to die, and this occurs by a process called programmed cell death or PCD, which can be separated from necrosis or accidental cell death (Pennell and Lamb, 1997). Senescence is the terminal phase in the development of an organism, organ, tissue or cell, where nutrients are remobilized from the senescing parts of the plant into other parts, and the cells of the senescing organ or tissue undergo PCD if the process is not reversed in time. LÄS MER

3. 22. Functional genomics of diapause in two temperate butterflies

   Författare :Peter Pruisscher; Karl Gotthard; Dieter Ebert; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diapause induction; adaptation; genomics; transcriptomics; populationsgenetik; Population Genetics;

   Sammanfattning : Natural selection will act on a given phenotype to maximize fitness in a particular environment, even if this would result in reduced fitness in other environments. In insects some of the strongest selection pressures act on timing life cycles to seasonal variation in environmental conditions, in order to maximize growth, reproduction, and to anticipate the onset of winter. LÄS MER

4. 23. Non-image-forming effects of light : Implications for the design of living and working environments

   Författare :Mathias Adamsson; Thorbjörn Laike; Maria Johansson; Yvonne de Kort; Institutionen för arkitektur och byggd miljö; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circadian rhythms; circannual; light exposure; melatonin; cortisol; sleep-wake behavior; perception; mood; spectral composition; measurement;

   Sammanfattning : Seasonal variation in mood and subjective well-being are common at geographical locations further away from the equator. The 24-h light-dark cycle is the main time cue for synchronizing the human circadian clock to the external day and night. LÄS MER

5. 24. Growth hormone and somatolactin function during sexual maturation of female Atlantic salmon

   Författare :Susana Benedet Perea; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Growth hormone; somatolactin; insulin-like growth factor I; GH; SL; IGFI; GHR; SLR; IGFIR; ovary maturation; reproduction; Atlantic salmon; spawning; pituitary;

   Sammanfattning : Background and aims: The growth hormone-insulin-like growth factor I (GH-IGF-I) system is known to act during sexual maturation of female salmonids, but the specific roles are not known. Somatolactin (SL) is a pituitary hormone closely related to GH and is only found in fish. In some species, including salmonids, there are two forms, SLa and SLß. LÄS MER

7. 25. Characterisation of the Clp Proteins in Arabidopsis thaliana

   Författare :Bo Zheng; Adrian K. Clarke; Vaughan Hurry; Cecilia Sundby-Emanuelsson; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant physiology; Arabidopsis; molecular chaperone; protein degradation; protease; Clp Hsp100; ClpP; stress response; antisense repression; chloroplast development; Växtfysiologi; Plant physiology; Växtfysiologi; molekylärbiologi; Molecular Biology;

   Sammanfattning : Unlike in the greenhouse, plants need to cope with many environmental stresses under natural conditions. Among these conditions are drought, waterlogging, excessive or too little light, high or low temperatures, UV irradiation, high soil salinity, and nutrient deficiency. LÄS MER