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Greening Earth? Science, Politics and Land Use in the Kyoto Negotiations

Can a deliberate enhancement of the natural uptake of atmospheric carbon dioxide in forests and agricultural lands contribute to the efforts to mitigation anthropogenic climate change? This is a question that has generated a great deal of debate and controversy since the inception of the multilateral climate negotiations in the early 1990s. This thesis offers an analysis of how this debate has pla

Extracting Syringe for determination of organochlorine pesticides in leachate water and soil-water slurry: A novel technology for environmental analysis

The Extracting Syringe (ESy), a novel membrane-based sample preparation technique directly coupled as an autosampler to gas chromatography, has been employed for the analysis of organochlorine pesticides (OCPs) in raw leachate water. The ESy has also been applied for extraction of OCPs from contaminated soil samples and its performance has been compared to liquid-solid extraction (LSE) and acceler

Artefactual Intelligence: The Development and Use of Cognitively Congenial Artefacts

How can tools help structure tasks to make them cognitively easier to perform? How do artefacts, and our strategies for using them, develop over time in cognitively beneficial ways? These are two of the main questions that are explored in the five papers collected in this thesis. The first paper details an ethnographic study conducted on people cooking in their homes. The study is a first pass ov

Charge Sampling Circuits and A/D Converters - Theory and Experiments

The analysis of general charge sampling technique is presented in this thesis. Charge sampling integrates input current instead of tracking input voltage to realize high speed and low voltage sampling. The analysis focuses on the performance of general charge sampling circuits for signal capture. The theoretical analysis here can be applied not only for the weak signal capture, but also for the no

Comparison of xylose fermentation by Saccharomyces cerevisiae strains carrying either xylose reductase and xylitol dehydrogenase or xylose isomerase

Background: Two heterologous pathways have been used to construct recombinant xylose-fermenting Saccharomyces cerevisiae strains: i) the xylose reductase ( XR) and xylitol dehydrogenase (XDH) pathway and ii) the xylose isomerase (XI) pathway. In the present study, the Pichia stipitis XR-XDH pathway and the Piromyces XI pathway were compared in an isogenic strain background, using a laboratory host

Occurrence and degradation of peptidoglycan in aquatic environments

Mechanisms controlling microbial degradation of dissolved organic matter (DOM) in aquatic environments are poorly understood, although microbes are crucial to global nutrient cycling. Bacterial cell wall components may be one of the keys in understanding the presence of slowly degrading DOM in nature. We found that dominant components of bacterial cell walls (D-amino acids (D-AA), glucosamine (Glu

Flower and cotyledon asymmetry in Brassica cretica: Genetic variation and relationships with fitness

Plants of the partially self-incompatible perennial herb Brassica cretica, derived from contralled cross- and self-pollinations within each of seven populations, were raised under uniform conditions and scored for two measures of developmental stability, flower asymmetry (quantified as the difference in length and width between opposite petals) and cotyledon asymmetry (quantified as the difference

Chlamydia screening--yes, but of whom, when, by whom, and with what?

The importance of screening programs in reducing the prevalence of genital chlamydial infections is stressed by the fact that the majority of infected persons are more or less asymptomatic. The use of oral contraceptives may mask infections affecting the upper genital tract. This imposes selective screening and rescreening of women with a history of pelvic inflammatory disease. The recent knowledg

Glutathione-s-transferase M1 and T1 polymorphisms and associations with type 1 diabetes age-at-onset.

Type 1 diabetes (T1D) is an autoimmune disease characterized by pancreatic beta cell destruction involving auto-reactive T-cells, pro-inflammatory cytokines, reactive oxygen species (ROS) and loss of insulin. Monozygotic twin studies show a 20-60% concordance with T1D indicating there may be an environmental component to the disease. Glutathione (GSH) is the major endogenous antioxidant produced b

Long-term outcome in patients with suspected normal pressure hydrocephalus

OBJECTIVE: To evaluate the outcome of patients with suspected normal pressure hydrocephalus at 6 months and 5 years after shunt Surgery. METHODS: Seventy-five patients (mean age, 72.5 +/- 9 yr), with normal pressure hydrocephalus symptoms were included. Fifty-four patients with positive lumbar infusion and/or cerebrospinal fluid tap tests received a cerebrospinal fluid shunt, whereas 21 patients w

Aneurysm pressure following endovascular exclusion

OBJECTIVES: To assess the effect of stent-graft implantation on the pressure within an abdominal aortic aneurysm. METHODS: Aneurysm exclusion was performed using an aorto-uniiliac stent-graft in eight patients. Following stent-graft implantation, pressure measurements were performed through a catheter adjacent to the graft in the aneurysm. This "aneurysm pressure" was compared with radial arterial

Power mapping and noise reduction for financial correlations

The spectral properties of financial correlation matrices can show features known from completely random matrices. A major reason is noise originating from the finite lengths of the financial time series used to compute the correlation matrix elements. In recent years, various methods have been proposed to reduce this noise, i.e. to clean the correlation matrices. This is of direct practical relev