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Micro- and macroevolutionary aspects of body size diversification and thermal adaptation in insects

För varje typ av djur finns en optimal storlek, men större är ofta bättre. För 300 miljoner år sedan var jättelika drakeflugor de största insekterna någonsin. Högre atmosfäriska syrekoncentrationer tros ha tillåtit dem att både flyga och utvecklas till jättar. Men idag är de största sländorna inte större än en mänsklig hand och tar decennier att utvecklas till vuxna. Men varför blir kråkmått ellerBody size and body temperature are the two most important traits in biology. In this thesis I show how these twovariables have shaped the evolution of insects over the last 300 million years. These variables are so important infact that three rules have been developed to summarize their effects: (1) bigger is better, (2) hotter makes yousmaller, and (3) hotter is better.Using primarily dragonflies

Induction of precocious intestinal maturation in T-cell deficient athymic neonatal rats

Aim: To investigate whether gut maturation could be induced precociously in an athymic T-cell deficient neonatal rat model. Methods: Fourteen day-old athymic (nude) rats (NIH-Foxn 1rnu) were gavaged with either phytohaemagglutinin - a lectin from red kidney beans (PHA); trypsin - a protease (Prot); or water - vehicle (control) as a single dose on one day or once a day for 3-day. The nude rats were

Electrocardiogram modeling during paroxysmal atrial fibrillation : Application to the detection of brief episodes

Objective: A model for simulating multi-lead ECG signals during paroxysmal atrial fibrillation (AF) is proposed. Significance: The model is of particular significance when evaluating detection performance in the presence of brief AF episodes, especially since annotated databases with such episodes are lacking. Approach: The proposed model accounts for important characteristics such as switching be

Resedabi Hylaeus signatusNT (Panzer) (Hymenoptera: Colletidae) påträffat i Botaniska trädgården i Lund.

A first find and a few subsequent observations of the oligolectic Large Yellow-Face Bee Hylaeus signatusNT (Panzer) were made during the second half of August in the Botanical Garden of Lund, province of Scania, Southern Sweden. About a dozen of specimens were attracted to a stand of Reseda luteola, one of its primary pollen sources. This bee is one of several newcomers among solitary bees in SwedA first find and a few subsequent observations of the oligolectic Large Yellow-Face Bee Hylaeus signatusNT (Panzer) were made during the second half of August in the Botanical Garden of Lund, province of Scania, Southern Sweden. About a dozen of specimens were attracted to a stand of Reseda luteola, one of its primary pollen sources. This bee is one of several newcomers among solitary bees in Swed

Development of the thermotolerant methylotrophic yeast hansenula polymorpha as efficient ethanol producer

Until recently, the methylotrophic yeasts, including Hansenula polymorpha, have not been considered as a potential producer of biofuels, particularly, ethanol from lignocellulosics. However it is already known that the thermotolerant methylotrophic yeast H. polymorpha is capable to ferment xylose, glucose and cellobiose, the main sugars of lignocellulosic hydrolysates, under elevated temperature.

”Filmreformens förste avantgardist” : Experimentfilmaren Peter Kylberg

This dissertation is about the Swedish filmmaker, painter and composer Peter Kylberg (1938). Kylberg’s nine films produced between 1959 and 1996 serves as a historical delimitation. A purpose of the study is to critically review the existing historical writing surrounding Swedish film culture and film politics, during the timespan in focus. The approach of the dissertation is chronological and pre

Generation of Ultrashort Pulses – From Femtoseconds to Attoseconds

Electronic dynamics takes place on the attosecond timescale and can thus only be studied using a tool with attosecond temporal resolution. High harmonic generation (HHG) provides coherent attosecond pulses in the extreme ultraviolet spectral region. The work presented in this thesis focuses on generating and characterizing ultrashort femtosecond pulses and using them for HHG, together with a gatin