Search for dissertations about: "nutrient interaction"

Showing result 1 - 5 of 51 swedish dissertations containing the words nutrient interaction.

2. 1. Direct and indirect effects of fish predation and excretion in aquatic food webs

   Author : José Luiz Attayde; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

   Abstract : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. READ MORE

4. 2. Learning time-varying interaction networks

   Author : Vinay Jethava; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; probabilistic graphical models; gene microarray expressions; dynamic interactome; time-varying interaction networks;

   Abstract : Most biological systems consist of several subcomponents whichinteract with each other. These interactions govern the overall behaviourof the system; and in turn vary over time and in response to internaland external stress during the course of an experiment. READ MORE

5. 3. Effects of warming and nutrient enrichment on feeding behavior, population stability and persistence of consumers and their resources

   Author : Wojciech Uszko; Sebastian Diehl; Lennart Persson; David Vasseur; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; consumer-resource; Daphnia; functional response; nutrient enrichment; parameter estimation; persistence; plankton; predator-prey; stability; temperature; type II; type III; warming;

   Abstract : Consumer-resource interactions are the basic building blocks of every food web. In spite of being a central research theme of longstanding interest in ecology, the mechanisms governing the stability and persistence of consumer-resource interactions are still not entirely understood. READ MORE

6. 4. Nutrient and energy sensing in skeletal muscle

   Author : Atul S Deshmukh; Karolinska Institutet; Karolinska Institutet; []
   Keywords : Skeletal muscle; AMPK; mTOR; glucose metabolism; exercise; Akt; TBC1D1 D4; CaMK; NO-cGMP;

   Abstract : Nutrient overload and physical inactivity often leads to the development of obesity and type 2 diabetes. Acute over-nutrition can induce insulin resistance, while physical exercise enhances skeletal muscle insulin sensitivity. Like every living cell, skeletal muscle senses nutrient and energy signals and to adjust metabolic flux. READ MORE

7. 5. On the investigation of chemical parameters reflecting microbial activity linked to nutrient availability in forest soil

   Author : Madelen Olofsson; Dan Bylund; Bengt-Gunnar Jonsson; Bjarne W. Strobel; Mittuniversitetet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Boreal forest; electrospray ionization; fungal biomass; hydrophilic interaction chromatography; hydroxamate siderophores; liquid chromatography-mass spectrometry; mineral amendment; aromatic acids; podzol soil;

   Abstract : As agrarian society developed, the most fertile soils able to sustain the nutritional requirements needed for high crop yield were assigned to farming, while the more penurious soils were left to uphold the forest ecosystems. Some temperate forests are developed on acidic soils considered to be nutrient poor, as much of the inorganic nutrients are entrapped in poorly weatherable soil minerals and not easily accessed by plant roots. READ MORE