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An evolutionary analysis of the aetiology and pathogenesis of juvenile-onset myopia

The available evidence suggests that both genes and environment play a crucial role in the development of juvenile-onset myopia. When the human visual system is examined from an evolutionary perspective, it becomes apparent that humans, living in the original environmental niche for which our species is genetically adapted (as hunter-gatherers), are either slightly hypermetropic or emmetropic and

Teoretiska aspekter på vetenskapligt samarbete i Europa under perioden 1870-1914

The purpose of this essay is to provide with a theoretical survey on the conceptions of "Nationalism" and "Internationalism", on a general level as well as applied to the scientific field. This pair of conceptions is useful to help us explain to understand the purpose of scientific cooperation and scientific-political motives behind the scientific society, in this case Europe during the period 187

Wrist-bridging versus non-bridging external fixation for displaced distal radius fractures: a randomized assessor-blind clinical trial of 38 patients followed for 1 year

BACKGROUND: Non-bridging external fixation has been introduced to achieve better fracture fixation and functional outcomes in distal radius fractures, but has not been specifically evaluated in a randomized study in the elderly. The purpose of this trial was to compare wrist-bridging and non-bridging external fixation for displaced distal radius fractures. METHOD: The inclusion criteria were women

A hemolytic assay for the estimation of functional mannose-binding lectin levels in human serum

A simple assay was developed to estimate functional mannose-binding lectin (MBL) levels in serum based on the principle of yeast-induced bystander lysis of chicken erythrocytes (ChE). The assay is sensitive to inhibition by ethylene glycol bis-(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) (which allows alternative pathway activation), ethylene diamine tetraacetic acid (EDTA), mannose,

Essays on Financial Models

Popular Abstract in Swedish Alla finansiella modeller bygger på antaganden, approximationer och förenklingar. Syftet med avhandlingen är att undersöka giltigheten och rimligheten i ett antal välkända och populära finansiella och ekonometriska modeller, med en tonvikt på de svenska aktie- och optionsmarknaderna. De ekonomiska och statistiska effekterna av alltför restriktiva modellantaganden undersThis thesis consists of five essays exploring the validity of some extensively used financial models with a focus on the Swedish equity and derivative markets. The essays are of both an empirical and a theoretical nature. In the first paper, The Search for Chaos and Nonlinearities in Swedish Stock Index Returns, an investigation of the presence of nonlinearities in general and chaos in particular

Fullskaleförsök med minirondeller

Kommunernas resurser för trafiksäkerhetsarbete är starkt begränsade och de räcker bara till att åtgärda några enskilda ”olycksdrabbade” platser. Åtgärden blir oftast en kostsam ombyggnad av t.ex. en korsning och den totala effekten av sådana åtgärder för kommunen blir marginell. Om resurserna satsas istället på helhetslösningar med små, billiga hastighetsdämpande åtgärder, som t.ex. minirondeller

Evolution of multi-stage dormancy in temporally autocorrelated environments.

Question: Under what circumstances does a capacity for multi-stage dormancy (i.e. dormancy in more than one life-stage) evolve? Mathematical methods: Optimization in stochastic environments. Results are derived both analytically and by simulations. Key assumption: There exists some trade-off between resources allocated to reproduction and adult dormant survival. Different shapes of this trade-off

New challenges for natural history collections

The status of natural history collections at universities have been evaluated many times during the second half of the last century. These evaluations have resulted in reduced financial support in different ways. The cause of the reduced financial support in different ways. The cause of the reduced support generally lies in the decreased use of collections in education and research. Among the natu

Origins and pathways of cerebrovascular vasoactive intestinal polypeptide-positive nerves in rat

In order to clarify the origins and pathways of vasoactive intestinal polypeptide (VIP)-containing nerve fibers in cerebral blood vessels of rat, denervation experiments and retrograde axonal tracing methods (true blue) were used. Numerous VIP-positive nerve cells were recognized in the sphenopalatine ganglion and in a mini-ganglion (internal carotid mini-ganglion) located on the internal carotid

P2U-receptor mediated endothelium-dependent but nitric oxide-independent vascular relaxation

1. The dilator effect of extracellular adenosine triphosphate (ATP) has mainly been characterized as a direct effect on smooth muscle or as an endothelium-dependent effect mediated by nitric oxide (NO) or prostaglandins. We tested the hypothesis that endothelium-derived hyperpolarizing factor (EDHF) may also be involved. Dilator effects were studied in vitro by continuous recording of isomeric ten

Endogenous NADPH-dependent aldose reductase activity influences product formation during xylose consumption in recombinant Saccharomyces cerevisiae

Introduction of the xylose pathway from Pichia stipitis into Saccharomyces cerevisiae enables xylose utilization in recombinant S. cerevisiae. However, xylitol is a major by-product. An endogenous aldo-keto reductase, encoded by the GRE3 gene, was expressed at different levels in recombinant S. cerevisiae strains to investigate its effect on xylose utilization. In a recombinant S. cerevisiae strai

Correlation between isoform composition of the 17 kDa myosin light chain and maximal shortening velocity in smooth muscle

The relation between the isoform distribution of the myosin 17 kDa essential light chain (LC17) and the mechanical properties of smooth muscle was investigated. The relative content of the basic (LC17b) and acidic (LC17a) isoelectric variants of the 17 kDa myosin light chain was determined in different mammalian smooth muscle tissues. The relative content of LC17b varied between muscles: rabbit re

Nest-attenders in the pied flycatcher (Ficedula hypoleuca) during nestling rearing: A possible case of prospective resource exploration

Visits to nest holes by birds other than their owners is a familiar phenomenon for students of breeding biology. In this study, we evaluate that behavior using a transponder reading system. Eighty-five males and females were Fitted with transponders at the end of the incubation period or just after hatching. Nest boxes were fitted with transponder readers from just after hatching until all nestlin