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Chemical communication in mating shore crabs Carcinus maenas

Popular Abstract in Swedish Att kunna lokalisera och bedöma en partner är en av de, evolutionärt sett, viktigaste egenskaperna hos alla sexuellt reproducerande organismer. För att möjliggöra detta använder sig ett djur sig av olika (visuella, taktila, akustiska och kemiska) signaler för inomartskommunikation. Jag har genom att studera kemiska signaler för inomartskommunikation (s.k. feromoner) hoLocating and evaluating a suitable partner for mating is one of the most important events in any sexually reproducing organism. To achieve this, an animal must be able to locate its partner over both long and short distances, and finally evoke the proper mating behaviour. This is made possible by use of conspecific signals picked up by one or several sensory systems, the most well investigated bei

Multipoint temperature and oxygen-concentration measurements using rotational coherent anti-Stokes Raman spectroscopy

A novel technique for coherent anti-Stokes Raman spectroscopy (CARS) measurements in multiple points is presented. With a system of cylindrical lenses, each laser beam is split into several focused beams, yielding separate planar boxcars configurations. Spectrally resolved CARS signals are detected at different heights on the CCD chip. With dual-broadband rotational CARS the setup is demonstrated

Synthesis of bioactive natural products and analogues

Popular Abstract in Swedish I flera tusentals år har människan använt sig av naturen till hjälp för att bota åkommor och krämpor. Det som hon har dragit nytta av då är att alla växter och plantor producerar flertalet små föreningar till skydd eller nytta för plantan. Dessa som föreningar kan då interagera med andra växter och organismer till exempel som ett skydd mot att bli uppäten, som en lockelNatural products have until recently provided the only remedy for treatment of diseases. The development of modern chemistry in the last centuries has opened the door for tapping into the chemical diversity found in nature. Synthetic natural products, together with analogues, are an important piece in the puzzle towards curing many ailments. In this thesis, synthetic endeavors towards different bi

Studies of Long-lived Radionuclides in the Environment - with Emphasis on 99Tc, 237Np and Pu Isotopes

Studies of the long-lived anthropogenic radionuclides 99Tc, 237Np, 239Pu and 240Pu were performed in marine and terrestrial areas contaminated by different accidental and controlled releases of radioactive materials. The three main sources discussed in this thesis are nuclear weapons tests, nuclear reprocessing plants and the Chernobyl accident. Results are mainly based on measurements of environm

The effect of forest nutrients status on ectomycorrhizal growth and community structure in response to minerals

Popular Abstract in Swedish Mycorrhiza är en samexistens mellan trädrötter och svampar i jorden. Svampen förser trädet med mineralnäringsämnen från jorden och i utbyte får den socker från trädet. Sockret produceras via fotosyntesen och transporteras sedan ner till rötterna där de förs vidare till svamphyferna. Det har visats att mycorrhizasvampar kan ta upp näringsämnen direkt från mineraler i jEctomycorrhiza are a symbiosis between trees and soil inhabiting fungi. The fungal hyphae ensheath the fine roots creating a mantle and grow in between root cells to create the Hartig net, where the exchange of carbon and mineral nutrients occurs. The ectomycorrhizal fungus is dependent on the host tree to receive the carbon it needs to grow. Trees with different nutrient deficiencies differ in t

Pollen Competition as a Target for Sexual Selection in Plants

Popular Abstract in Swedish Hos djur är det vanligt att hannarna slåss om att få para sig med honorna, medan honorna är mer kräsna i sitt val av partner. Är det möjligt att växter gör på samma sätt? I min avhandling har jag visat hur pollen tävlar om att få befrukta de honliga fröämnena i pistillen hos styvmorsvioler (Viola tricolor). Det ligger även i honans intresse att välja en partner som prodAccording to the theory of sexual selection, traits can evolve because they confer a mating advantage in competition with members from the same sex. In animals, sexual selection is considered as an important evolutionary force. In this thesis I have investigated the potential for sexual selection in plants. I have concentrated on the phase of reproduction that occurs after pollinators have deposit

Sociala dimensioner i hållbar samhällsplanering

Vilka faktorer skall man prioritera i samhällsplanering? Hur skall man analysera dem? Hur hänger olika faktorer samman? Hur skall man arbeta med sociala dimensioner som verktyg i planering? De prioriterade sociala dimensionerna i bostadsplanering har formulerats som allsidig demografisk struktur, rimliga omflyttningstal och attraktiva boendekvaliteter. I skriften analyseras planeringsstrategier kr

A mixed-ordered Logit approach to investigate correlations among different affordances in fire evacuation

The evaluation of the effectiveness of safety installations (such as emergency exits, lighting, etc.) is a key factor to improve the evacuation performance of buildings or transportation systems. In fact, even though an installation is designed to achieve a given design goal, it could happen it does not perform as intended. According to the Theory of Affordances, this could be interpreted in relat