Search for dissertations about: "Snail"

Showing result 6 - 10 of 39 swedish dissertations containing the word Snail.

2. 6. Three-wave mixing in Josephson travelling-wave parametric amplifiers

   Author : Hampus Renberg Nilsson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; three-wave mixing; lumped-element; four-wave mixing; SNAIL; Josephson junction; travelling-wave parametric amplifier; parametric amplifier; parametric amplification; resonant phase matching.; rf-SQUID;

   Abstract : This work explores possibilities of building a wide-band, quantum-limited low-noise amplifier by means of three-wave mixing (3WM) in different kinds of Josephson travelling-wave parametric amplifiers (TWPAs). We extend the theory of the continuous three-mode model to include any number of up-converted modes in the small frequency limit where the frequency dispersion is close to linear. READ MORE

4. 7. Organohalogen contaminants in wildlife from the Yangtze River Delta : Development of methods and assessments of legacy and emerging persistent organic pollutants

   Author : Ge Yin; Åke Bergman; Gang Yu; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Organochlorine pesticides; flame retardants; chlorinated paraffins; PCBs; PCDEs; PBDEs; PCDD Fs; dicofol; environmental monitoring; bioindicator; shellfish; snail; bird eggs; miljökemi; Environmental Chemistry;

   Abstract : Rapid economic development has occurred during the past few decades in China with the Yangtze River Delta (YRD) area as one of the most progressive areas. The urbanization, industrialization, agricultural and aquaculture activities result in extensive production and application of chemicals. READ MORE

5. 8. Invading Herbivory. Effects of the Golden Apple Snail (Pomacea canaliculata) in Asian Wetlands

   Author : Nils Carlsson; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gastropoda; invasive species; golden apple snail; herbivory; wetland functioning; biodiversity; sustainable control; indigenous predators; size-dependent competitive ability; akvatisk ekologi; limnologi; Marinbiologi; limnology; Hydrobiology; aquatic ecology; marine biology;

   Abstract : The South American golden apple snail (Pomacea canaliculata) was intentionally introduced to aquacultures in South East Asia to produce snails for human consumption, but the aquatic snails soon escaped and started to consume large amounts of rice seedlings. The aim of this thesis was to quantify the effects of this invasive herbivore on aquatic plants in natural wetlands since previous research has focused on effects of the snail in rice fields. READ MORE

6. 9. Predator induced phenotypic plasticity in a freshwater snail

   Author : Thomas Lakowitz; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; dispersal; Radix balthica; shell morphology; reaction norm; multiple predators; cost of plasticity; intraspecific competition; inerspecific competition;

   Abstract : In this thesis I examined a phenotypically plastic defence in a common freshwater snail, Radix balthica. Adaptive prey defences may involve behavioural, life-history or morphological changes. Snails are important species in freshwater systems. READ MORE

7. 10. Living on the edge : effectiveness of buffer strips in protecting biodiversity on boreal riparian forests

   Author : Kristoffer Hylander; Christer Nilsson; Bengt Gunnar Jonsson; Ellen Macdonald; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; boreal forest; bryophyte; buffer strip; ecological boundary; edge effect; headwater stream; land snail; liverwort; moss; phytometer; riparian forest; substrate; terrestrial gastropod; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Abstract : The objective of this thesis is to evaluate the ecological consequences of buffer strip retention on riparian and terrestrial biodiversity. Earlier studies on forest buffer strips have evaluated their effectiveness in relation to water quality and aquatic biota. However, forests along streams are species rich habitats for many organism groups. READ MORE