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Visar resultat 1 - 5 av 2037 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Intramolecular isotope analysis reveals plant ecophysiological signals covering multiple timescales

    Författare :Thomas Wieloch; Jürgen Schleucher; Mats Nilsson; Gerd Gleixner; Lisa Wingate; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NMR spectroscopy; tree ring; isotope ratio; isotope effect; intramolecular 13C 12C signal; carbon allocation; acclimation; plant performance; climate reconstruction; plant ecophysiology;

    Sammanfattning : Our societies' wellbeing relies on stable and healthy environments. However, our current lifestyles, growth-oriented economic policies and the population explosion are leading to potentially catastrophic degradation of ecosystems and progressive disruption of food chains. LÄS MER

  2. 2. Spatiotemporal Evolution of Neotropical Organisms: New Insights into an Old Riddle

    Författare :Alexandre Antonelli; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Neotropics; Biodiversity patterns; Speciation models; Andean uplift; K T Event; Biogeography; Phylogenetics; Molecular dating; Rubiaceae; Chloranthaceae; Campanulaceae; Tetrapods; Biological systematics;

    Sammanfattning : Nowhere else on Earth are there so many species of plants and animals as in the Neotropical region. Yet, many questions remain concerning the causes underlying such outstanding diversification. LÄS MER

  3. 3. The neurotoxin β-N-methylamino-L-alanine (BMAA) and 2,4-diaminobutyric acid (DAB) : possible risk of human exposure, and the effect and function in diatoms

    Författare :Sea-Yong Kim; Sara Rydberg; Sandra Banack; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; växtfysiologi; Plant Physiology;

    Sammanfattning : The toxic secondary metabolites β-N-methylamino-L-alanine (BMAA) and 2,4-diaminobutyric acid (DAB) produced by phytoplankton groups such as cyanobacteria, diatoms and dinoflagellates are known to cause neurotoxicity in vertebrates. BMAA has been linked to development of the neurodegenerative diseases amyotrophic lateral sclerosis/Parkinsonism dementia complex (ALS/PDC) and Alzheimer's disease. LÄS MER

  4. 4. Botanical Repellents and Pesticides Traditionally Used Against Haematophagous Invertebrates in Lao PDR

    Författare :Chanda Vongsombath; Thomas Jaenson; Raimondas Mozuraitis; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ethnobotany; fly larvae; Lao PDR; medical entomology; mosquito repellents; myiasis; plant-based insecticides; terrestrial leeches; Haemadipsidae; Systematics and phylogenetics; Systematik och fylogeni; Organism biology; Organismbiologi; Biologi med inriktning mot systematik; Biology with specialization in Systematics;

    Sammanfattning : Haematophagous parasites and disease vectors such as leeches, ticks, mites, lice, bed bugs, mosquitoes, and myiasis-causing fly larvae are common health problems in Lao Peoples Democratic Republic (Lao PDR). A main aim of my field work in Lao PDR in 2006-2010 was to document traditional knowledge among different ethnic groups about plants that people use to repel or to kill blood-feeding invertebrates. LÄS MER

  5. 5. Spikemoss patterns : Systematics and historical biogeography of Selaginellaceae

    Författare :Stina Weststrand; Petra Korall; Michael J. Donoghue; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; classification; historical biogeography; lycophytes; nomenclature; phylogeny; Selaginella; Selaginellaceae; systematics; fylogeni; historisk biogeografi; klassifikation; lummerväxter; nomenklatur; Selaginella; Selaginellaceae; systematik; Biologi med inriktning mot systematik; Biology with specialization in Systematics;

    Sammanfattning : Selaginellaceae, spikemosses, is a heterosporous plant family belonging to the lycophytes. With an estimated age of some 350 million years, the family is historically important as one of the oldest known groups of vascular plants. Selaginellaceae is herbaceous with a worldwide distribution. However, the majority of the ca. LÄS MER