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Din sökning på "swedish" gav 91003 sökträffar

Genetic modeling of the Hippo pathway in hematopoietic stem cells

Hematopoiesis is the process of blood formation from a limited pool of hematopoietic stem cells (HSCs). These rare stem cells can both self-renew to maintain the HSC pool, and differentiate to continuously replenish lost blood cells. The mechanisms of HSC regulation are not fully known. The aim of this thesis was to study the role of the Hippo signaling pathway in HSCs. The Hippo pathway is a newl

Pitfalls in Interpreting Umbilical Cord Blood Gases and Lactate at Birth

Acid-base status in umbilical cord blood is an objective measure of the fetus’ exposure to and ability to handle hypoxia. The objective of this thesis was to clarify some of the methodological pitfalls in interpreting umbilical cord blood gases and lactate values at birth. Study I pinpoints the methodological confounding in calculating base deficit (BD) with algorithms used in different brands of

Endoplasmic Reticulum Dynamic Structural Changes in Neurons: The Fission-Fusion Phenomena

The endoplasmic reticulum (ER) is crucial for protein synthesis and protein maturation, is involved in cell stress and serves in neurons as the major intracellular Ca2+ store. Neuronal ER forms a continuous network of cisterns and tubules extending from soma to a subset of dendritic spines. The continuity of ER structure is important for maintaining ER basic functions and necessary for proteins an

På AI-teknikens axlar : Om kunskapssociologin och stark artificiell intelligens

This dissertation is concerned with Sociology’s stance in the debate on Strong Artificial Intelligence, i.e. such AI that is able to shape new knowledge without human interference. There is a need for sociologists to realize the difference between two approaches to constructing AI systems: Symbolic AI (or Classic AI) and Distributed AI – DAI. Sociological literature shows a largely critical attitu

Playing at Work : Organizational Play as a Facilitator of Creativity

This thesis investigates how play may benefit creativity in organizational contexts. Play and playfulness have previously been linked to creativity in children and adults, but empirical organizational research is scarce. A widely accepted definition of creativity is that it involves the production of something that is both novel and appropriate. Play is defined as a behavioral approach that is cha

Radionuclide Production with PET Cyclotrons, Applications and Preclinical Experiments

Nuclear medicine is based on the radiotracer principle of George de Hevesy and the magic bullet concept by Ehrlich and focuses on the diagnosis, the treatment of diseases and the investigation of normal states within the human body using radiopharmaceuticals. A radiopharmaceutical is an atom or a chemical compound in which one or several atoms are replaced with a radionuclide. Several diagnostic a

Sesquiterpene synthases in Artemisia annua: Cloning, Expression, and Characterisation of the Recombinant Enzymes

Plants produce a multitude of different compounds that may have biotic effects. Artemisia annua, produces a compound used as a drug against multi-drug-resistant strains of Plasmodium falciparum, the parasite causing malaria. The compound, artemisinin, is a sesquiterpene and is an essential component for the production of artemisinin drugs against malaria. In a first critical step of the biosynthes

A green future with thawing permafrost mires? : a study of climate-vegetation interactions in European subarctic peatlands

Climate projections indicate that Arctic and sub-Arctic regions are facing a significant change in climate during the 21st century. With warmer temperatures precipitation is also expected to increase, and in particular winter precipitation. These changes are likely to have large impacts on the Arctic and subarctic environment, and extensive research has focused on ecosystem-climate interactions in

Visualization and Simulation Technology in Healthcare - From a technology-centered to a human-centered perspective

With the aid of modern computer technology the application of visualization and simulation technology has become increasingly important in today’s society. Through computer modelling it is possible to experience, understand and explore environments, systems or objects in two or three dimensions and to see, hear and sometimes tangibly feel them. It may be environments or objects that do not yet exi

Methods to Improve and Evaluate Spatial Data Infrastructures

This thesis mainly focuses on methods for improving and evaluating Spatial Data Infrastructures (SDIs). The aim has been threefold: to develop a framework for the management and evaluation of an SDI, to improve the accessibility of spatial data in an SDI, and to improve the cartography in view services in an SDI. Spatial Data Infrastructure has been identified as an umbrella covering spatial data

Balance, gait performance and muscular strength in the elderly

Fracture incidence is higher in urban than in rural inhabitants. Background factors such as physical activity and workload may have an influence on the tendency to fall, leading to fractures. We found that elderly women with a recent fracture of the distal radius appear to have impaired balance, an impairment that seems to normalise with time after fracture. The aim of this study was also to get n

Aspect, tense and mood : Context dependency and the marker LE in Mandarin Chinese

The grammatical marker LE in Mandarin Chinese can occur in two syntactic positions, either immediately following the verb or at the end of a sentence. Traditionally, it has been described as two homophonous but syntactically distinct morphemes, verbal LE and sentence-final LE. This view seems to be based on assumptions about (1) the historical origin of LE, (2) the relation between LE and its coun

Extreme hemodilution: Effects of inhalation anesthetics, hypoxia, and blood loss. An Experimental study in pigs.

Hemodilution reduces the need for blood transfusion and hereby the risk for transmission of infectious agents. The present study investigated effects on systemic and myocardial circulation and oxygenation, and blood lactate concentrations; induced by nitrous oxide, isoflurane, hypoxia, and uncompensated blood loss, in pigs hemodiluted to a hematocrit of 11%. In addition, indicators of hypovolemia

Verification of Dose Calculation Algorithms in Treatment Planning Systems for External Radiation Therapy: A Monte Carlo Approach

This thesis presents a new verification concept, the virtual accelerator, for dose calculation algorithms used in treatment planning systems (TPSs) for external beam radiotherapy. The algorithm input data required to implement a treatment unit in the TPS are generated by Monte Carlo simulations as are the beam reference data needed for the subsequent evaluation of the dose calculation algorithm. T

Numerical Modelling and Analysis of Orthogonal Metal Cutting

Most components in use in our society have undergone a machining process at some stage within its manufacturing cycle. As a result, the economics of the machining process plays an important role in the manufacturing costs. There are several reasons for developing a rational approach to material removal, such as improving cutting techniques, producing products with enhanced precision, and increasin

Simulations of Transport Phenomena and Porous Structures Using Dissipative Particle Dynamics

The topic of this work is simulations of porous materials and transport phenomena at a mesoscopic length scale, i.e., a length scale larger than an individual atom but smaller than the continuum. The porous material studied is a membrane used in fuel cells. Mass transfer has also been studied in the membrane. Heat and mass transfer has been studied in parallel plate channels, first in saturated ch

Comparative optics of prosobranch eyes

Functional aspects of the large diversity of eye design in prosobranch molluscs was investigated using morphological and optical methods. Three species from different habitats were investigated. Littorina littorea from Scandinavian intertidal rock habitats, Strombus raninus and S. gigas from tropical sand-flats and Ampularia sp. from heavily vegetated habitats in tropical fresh-water. Littorina a

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The dissertation deals with two part-studies. The main focus is a field study the purpose of which is to understand incurable disease and death as hands-on experiences at the player's level. With the aid of observations and interviews, nine dying people, relatives and community nurses are followed in the families? homes over time. The second part-study is a discourse analysis of Danish health-poli

Understanding Weather effects on, in, and from large Herbivore Population Dynamics

Large herbivores are monitored for various reasons in many areas around the world. Data from such monitoring can be of varying degree of detail and extent. Several studies have shown that we need extensive amounts of data with a high degree of detail to be able to understand anything from it. Nevertheless, data in the less detailed form of annual censuses of large herbivore densities and weather i

Aspects of Morphological and Stylistic Variation of the Verb in Erotokritos

The aim of the present study is to examine the polytypia (morphological variation) and semantic differentiations of the verb in Vitsentzos Kornaros' Erotokritos, to understand how these shape poetic style. We examine the stems and the endings in the imperfective active forms. Moreover, we investigate the augmented forms because at an early stage we found that Kornaros employs a degree of poetic li