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Sorption to soil of hydrophobic and ionic organic compounds: measurement and modeling

REA Auditado

The sorption of organic compounds to soil, sediments and dissolved organic matter affects the fate of organic compounds. Given the central role of this process in environmental transport, distribution, and (bio)degradation processes, it needs to be well-understood and represented in risk assessment of chemicals in the environment. In this thesis soil-sorption of various organic compounds was studied in order to improve the scientific basis for representing sorption in risk assessment. Chapters 2 to 5 study the sorption of hydrophobic organic chemicals.

Tema: general: 

• General

Connectivity and neurotransmission in experimental epileptogenesis

REA Auditado

This thesis summarizes the research performed by Pieter van Eijsden on two important aspects of the development of temporal lobe epilepsy: changes in white matter connectivity and hippocampal neurotransmitter imbalance. A major theme in this thesis is the characterization of changes that occur before the onset of spontaneous seizures in order to distinguish these from changes that occur due to spontaneous seizures.

Tema: general: 

• General

Glycerol dialkyl glycerol tetraether membrane lipids in lacustrine environments and their application as proxies for palaeoclimate reconstructions

REA Auditado

Lacustrine sediments often contain relatively high amounts of organic matter because of limited bottom water oxygenation and relatively high sedimentation rates. The membrane lipids of Crenarchaeota, a major group of the domain Archaea, consist of isoprenoid glycerol dialkyl glycerol tetraether (GDGTs) containing cyclopentane moieties, a characteristic considered an adaptation mechanism to temperature of the membrane.

Tema: general: 

• General

Shaken, but not stirred—Potts model coupled to quantum gravity

REA Auditado

We investigate the critical behaviour of both matter and geometry of the three-state Potts model coupled to two-dimensional Lorentzian quantum gravity in the framework of causal dynamical triangulations. Contrary to what general arguments on the effects of disorder suggest, we find strong numerical evidence that the critical exponents of the matter are not changed under the influence of quantum fluctuations in the geometry, compared to their values on fixed, regular lattices.

Tema: general: 

• Ciencias Sociales›Educación

Late-life depression: structural brain abnormalities, treatment and risk factors

REA Auditado

Major depression is a prevalent disease among the elderly, significantly decreasing the quality of life. The age of first onset of depression can be early in life, so called early-onset depression (EOD), as well as first occur in old age, i.e. late-onset depression (LOD). Some previous studies have suggested aetiological differences between EOD and LOD in the elderly. However, the number of these studies investigating elderly EOD and LOD patients is small. Therefore the importance of age of onset in the aetiology of late-life depression remains unclear.

Tema: general: 

• General

Optical properties of semiconducting nanowires

REA Auditado

Semiconductor nanowires of high purity and crystallinity hold promise as building blocks for opto-electronical devices at the nanoscale.. They are commonly grown via a Vapor-Liquid-Solid (VLS) mechanism in which metal (nano) droplets collect the semiconductor precursors to form a solution which, when saturated, leads to the growth of a wire underneath the droplet. After a brief discussion of this general mechanism, the growth of InP and ZnO nanowires is detailed. The grown InP nanowires have an integrated alloy particle and have on average diameters of 50 nm and lengths of 10 μm.

Tema: general: 

• General

Clustering and self-assembly in colloidal systems

REA Auditado

A colloidal dispersion consists of small particles called colloids, typically tens of nanometers to a few micrometers in size, suspended in a solvent. Due to collisions with the much smaller particles in the solvent, colloids perform Brownian motion: randomly directed movements that cause the particles to diffuse through the system. In principle, this motion allow the system of particles to explore all configurations available to them, sampling all of phase space according to the Boltzmann distribution.

Tema: general: 

• General

Atom-molecule coherence in Bose gases

REA Auditado

The interaction properties of atoms are, at low
temperatures, fully determined by the s-wave scattering length of
the interatomic interaction potential. The magnitude and sign of
this quantity strongly depend on the presence of bound states in
this potential and, more precisely, on the energy of the bound
state that is closest to the continuum threshold. In the
multichannel case of a Feshbach resonance, the energy of the two
colliding atoms in the incoming open channel is close to the
energy of a bound state, i.e., a molecular state, in a coupled
closed channel.

Tema: general: 

• General

Interpatient registration and analysis in clinical neuroimaging

REA Auditado

The first part of this thesis deals with brain infarct patterns in patients with differing degrees of stenosis of the internal carotid artery. Stenosis or narrowing of the internal carotid artery (ICA) is a well-known cause of infarcts or strokes. Infarct maps are used to study differences in infarct pattern in patients with ICA stenosis. Infarct distribution maps for each stenosis category were created by mapping each CT image to an average brain image and applying this transformation to the manually segmented infarcts. The construction of the average CT brain image proceeded in two steps.

Tema: general: 

• General

Ecology and membrane lipid distribution of marine Crenarchaeota: Implications for TEX86 paleothermometry

REA Auditado

Archaea form one of the three domains of life on Earth and together with the bacteria form the prokaryotes. In the marine environment planktonic Archaea consist of two major groups, the Crenarchaeota and the Euryarchaeota of which the former appears to be the most abundant and may account for ca. 20% of all prokaryotic cells in the global ocean. Despite the fact that marine Crenarchaeota constitute a substantial fraction of the picoplankton in the world oceans, little is known about their basic metabolic requirements.

Tema: general: 

• General