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Under aerobic conditions, most yeasts such as Kluyveromyces lactis, prefer the respiratory pathway and some, such as Saccharomyces cerevisiae prefer less energy efficient fermentative pathway for their energy metabolism. These two metabolic strategies are also known as Crabtree negative and Crabtree positive respectively, and the evolution of the latter has lately been explained by the “make-accum

Aquaporins, or Major Intrinsic Proteins (MIPs), are integral proteins that facilitate transport of water and other small neutral solutes across biological membranes. They belong to a well conserved and ancient family of proteins, present in all organisms ranging from bacteria to plants and humans. The aquaporin family in plants is large, indicating complex and regulated water transport within the

This thesis concerns the interplay between the lipid phase behaviour, domain formation and the permeability of bilayer membranes. An essential part of this work has been the understanding of the phase transitions and equilibrium properties of lipid bilayers. In this approach experimental results of lipid phase behaviour have been correlated to theoretical descriptions of the systems. An isothermal

This work is not so much about religion as about individual religiosity. It is primarily about people practicing Zen, less about Zen Buddhism as a systematic ideology or philosophy. I set out from the start to try to explore the wide gap between theory and practice in Zen. The more abstract doctrines and idealized norms have had a tendency to dominate works on Zen, confessional as well as scholast

Due to our own preference for bright light, we tend to forget that many insects are active in very dim light. The reasons for nocturnal activity are most easily seen in tropical areas of the world, where animals face severe competition for food and nocturnal insects are able to forage in a climate of reduced competition and predation. Generally nocturnal insects possess superposition compound eye

ECL cells are endocrine/paracrine cells located in the acid-producing part of the stomach. They are important regulators of gastric acid secretion in the stomach by virtue of their histamine synthesizing and secreting capacity. Histamine in turn stimulates parietal cells to secrete acid. The ECL cell also contains the endocrine polypeptide chromogranin A (CGA) and CGA-derived peptides such as panc

The insertion of Mg2+ into protoporphyrin IX represents the first committed step in the chlorophyll and bacteriochlorophyll biosynthetic pathways. The reaction is catalyzed by the multisubunit enzyme Mg-chelatase, which consists of three subunits, known as I (molecular weight ~40 kDa), D (~70 kDa), and H (~140 kDa). To fully understand this first step in chlorophyll biosynthesis each protein compo

This thesis is based on a study of Roman glass vessels found on non-Roman/native sites - chiefly of Roman Iron Age date (AD 0-400) - beyond Hadrian’s Wall in northern Britain. Roman glass vessels have been discovered on 60 sites in total, the majority of which are settlements of various types, and only a minor part are graves. As a consequence of this, the greater part of the material is strongly

In generally accepted and applied flamelet combustion models, a turbulent flame is mainly assumed distorted by the large-scale turbulence eddies, whereas small-scale turbulence effects on the local flamelet structures are neglected. However, in a lot of industrial applications rather high turbulent intensities are often imposed, which induce turbulence scales at ranges smaller than the flame thick

The properties of the basic building blocks of nuclear matter, the quarks, and their interactions are not known in detail, largely because observations are complicated by the confinement of quarks in composite particles. New insights can be gained from the study of nuclear matter in a deconfined phase, like the form of matter that the Universe consited of early in its evolution according to the Bi

The price of a good is said to be nonlinear if the unit price not is constant but depends on some aspect of the quantity (or quality) purchased. This form of pricing is commonly used in many industries, e.g. the electricity and water industries, and has many desirable properties. For example, nonlinear pricing is often necessary for (Pareto) efficiency and nonlinear pricing can be used as an instr

One month and one year after acute myocardial infarction (AMI) (n=296), coronary artery bypass grafting (CABG) (n=99) and percutaneous coronary intervention (PCI) (n=18) patients completed a questionnaire for self-assessment of quality of life (QoL) during the period 1989?1991. Patients differed from age- and sex-matched controls (n=88) in both somatic and emotional dimensions, but less after one

Speaker age is an important paralinguistic feature in speech which has to be considered in the study of phonetic variation. Knowledge about this feature may be used to improve speech technology applications, e.g. automatic speech recognition and speech synthesis. The present thesis describes six studies of several phonetic aspects of age-related variation in speech. As the speech production mecha

This work presents optical methods for diagnosing cancer. A complementary method for diagnosing eye cancer was investigated using a technique developed within this work named transscleral optical spectroscopy (TOS). Furthermore, nano-sized crystals doped with lanthanides were exploited as probes for fluorescence imaging with direct applications to preclinical cancer research. Almost all intraocul

The thesis consists of three essays on currency markets, equilibrium and expectations. The first essay examines currency markets in the setting of a temporary equilibrium model with two currencies and two central banks, where consumers have one-point expectations. Assuming that both central banks use floating exchange rate policies it is shown that if consumers have common expectations the curren

The triumphal procession staged Roman conquest and supremacy, featuring the defeated ‘other’ as opposed to the victorious ‘self’ in a rather fixed role-playing. This thesis takes as its theoretical premise that these ritually recurrent and visually emphatic processions both conveyed and constructed Roman views of the self and the other, and that they can be studied as formative expressions of such

The overall aim of this project was to investigate the drop break-up process in milk homogenisers. This was done by measurements and calculations of the flow fields in the gap region and by visualisation of drops being broken up. To make visualisation and measurements possible, two scale models of a homogeniser gap were developed. The full-scale model was a direct copy of the gap in a production-

A specific group of heat shock proteins, the so called small heat shock proteins (sHsps), exists in all organisms but are especially abundant in plants. The sHsps prevent aggregation of other proteins (substrate proteins) during transient heat and oxidative stress. Molten globule forms of the substrate proteins are kept in a re-folding competent state by binding onto the outer surface of the sHsp.

In this thesis effects of liming on ectomycorrhiza have been studied in relation to effects on root colonization, fungal growth and nutrient uptake. In field experiments the effects of liming on ectomycorrhizal colonization of root tips were variable, possibly due to different soil types and climatic variations. However, a changed mycorrhizal community structure could be detected. Laboratory studi

The old, world-wide phenomenon of playing board games has received little attention among scholars studying the ancient cultures. This thesis collects and analyses game-related material from Bronze Age Crete, defines the field of research and provides a framework with definitions and typologies. A further goal is to use the results of the analyses to extend beyond the archaeological material and e