We study the shear flow of two-dimensional foams, i.e., a monolayer of bubbles floating on a soapy solution. We successfully connect local and global flow behaviour
The central focus of this thesis was to examine the role of self-regulation principles in predicting and changing self-care behaviors of diabetes type 2 patients. Overall, the results in this... Show moreThe central focus of this thesis was to examine the role of self-regulation principles in predicting and changing self-care behaviors of diabetes type 2 patients. Overall, the results in this thesis indicate that self-regulation cognitions and skills might be important intervention targets of future diabetes (weight) interventions. The studies in this thesis indicated that self-regulatory cognitions were related to diabetes behavior (weight regulating behavior), HbA1c and drop-out from a diabetes weight loss intervention. Show less
Het proefschrift beschrijft verschillende technische zaken die verbeterd of veranderd kunnen worden om betere metingen te kunnen doen met een AFM in biologisch onderzoek, zaken die kunnen leiden... Show moreHet proefschrift beschrijft verschillende technische zaken die verbeterd of veranderd kunnen worden om betere metingen te kunnen doen met een AFM in biologisch onderzoek, zaken die kunnen leiden tot een hogere gevoeligheid, een bredere toepassing of beter begrip en interpretatie van de metingen, en voorbeelden van de toepassing van dergelijke verbeteringen op verschillende systemen die in biologisch of biomedisch onderzoek in de belangstelling staan. Een voorbeeld van dergelijk onderzoek beschreven in het proefschrift is de rol van collageen-fibers in de mechanische sterkte van de vaatwand van de aorta en hun rol in het mogelijke falen van die vaatwand: dergelijke aneurysma's zijn meestal dodelijk. Show less
This study examines the mobilisation of South African women into trade union activities between the period 1973 and 2003. Firstly, it underscores the role of South African women in fighting for... Show moreThis study examines the mobilisation of South African women into trade union activities between the period 1973 and 2003. Firstly, it underscores the role of South African women in fighting for workers’ rights in the workplace and their contributions in the building of the labour movement at the national level. In explaining the mobilisation of women, this research focuses on their social biography. It explores women’s experiences in society, the family (or personal relationships), the workplace and trade unions. It is shown that women’s experiences within all these different social settings are interconnected and influence their consciousness. Based on these observations, I argue that the activism of South African women takes place at the level of race, class and gender. Secondly, the study focuses on the participation of women trade unionists in the South African transition. It argues that women the struggles of women in the trade unions and the workplace have contributed significantly to the proposals adopted by the Women’s National Coalition which were subsequently incorporated into political negotiation process during the transition and ultimately into the constitution. Show less
A number of chitosan derivatives were synthesized and compared to the previously synthesized derivatives for their permeation enhancing activity. Using these derivatives insulin nanoparticles were... Show moreA number of chitosan derivatives were synthesized and compared to the previously synthesized derivatives for their permeation enhancing activity. Using these derivatives insulin nanoparticles were prepared and their effect was compared to the free polymer and insulin in Caco-2 cells. The results suggested that the paracellular transport of insulin across the intestinal cells was more pronounced with the free soluble polymer due to the availability of more positive charge in free soluble polymer. A novel Gas Empowered Drug Delivery (GEDD) system was then designed using CO2 force to transport insulin, Polyethylene Oxide (PEO) as well as trimethyl chitosan (TMC) to the surface of the small intestine. PEO and TMC act as mucoadhesive polymer and permeation enhancer in the system, respectively. The GEDD system is enterically coated to protect the protein against the acidic environment of the stomach. The insulin transport across the intestinal membrane has been increased up to 9 times in the ex-vivo studies in sheep__s intestine using the GEDD system. Moreover, the in-vivo results showed a 5.5 fold enhancement in comparison to free insulin in rabbits as well as a relative bioavailability of 1.1 _0.4% in compare to the s.c. injection. The GEDD system is easy to manufacture and shows promising future for peroral delivery of peptide drugs. Show less
The thesis describes the application of several different magnetic resonance (MR) techniques to study the effects of the progression of disease in a transgenic mouse model of Alzheimer's. Using MR... Show moreThe thesis describes the application of several different magnetic resonance (MR) techniques to study the effects of the progression of disease in a transgenic mouse model of Alzheimer's. Using MR imaging, the amyloid plaque deposition was visualized and the plaque load quantified in the same mice as they aged. Concurrently the transverse relaxation time (T2) was measured in affected brain regions and shown to decrease over time as plaque-load increased. To study the neurochemical profile in the mouse brain brain both one- (1D) and two-dimensional (2D) MR spectroscopic techniques were employed. 1D MRS is widely used in similar research, but has limited spectral resolution. To overcome this limitation, a 2D MRS technique was implemented and optimized for use in mouse brain. This technique, L-COSY, allowed the detection of several metabolites which were not visible using standard 1D MRS techniques. This technique was subsequently used to study the effects of Alzheimer's on the neurochemical profile. Observed changes were correlated with plaque deposition. Show less
What is an effective and efficient enforcement policy for fire safety in the catering industry? When and why is an informal, cooperative enforcement style through warnings, persuasion and advice (a... Show moreWhat is an effective and efficient enforcement policy for fire safety in the catering industry? When and why is an informal, cooperative enforcement style through warnings, persuasion and advice (a so called compliance strategy) effective in inducing compliance with the fire safety regulation? The standard economic model of enforcement stresses the importance of immediately punishing individuals and firms for non-compliance (a deterrence strategy). Part I of this thesis analyzes the economic literature to discuss whether and when a compliance strategy can be beneficial. It discusses which enforcement method (private, administrative or criminal) is effective and efficient to enforce safety standards. Part II of this thesis analyzes the optimal enforcement policy for the case of fire safety in the catering industry in the Netherlands. Enforcement officials have been interviewed to examine the use of a compliance strategy in practice. The benefits and costs of the enforcement efforts of the past years are estimated to see whether these efforts have been a desirable investment. Also, the compensation of the victims of the Volendam disaster is investigated to analyze the incentive to take precautions. Finally, a simulation of different enforcement policies in a representative municipality examines which policy is efficient. Show less
This thesis describes the role of urodynamic parameters, like detrusor overactivity and urethral instability, in relation to neuromodulation treatment options sacral neuromodulation and... Show moreThis thesis describes the role of urodynamic parameters, like detrusor overactivity and urethral instability, in relation to neuromodulation treatment options sacral neuromodulation and extracorporeal magnetic innervation. Urethral instability is a good parameter to predict succcesfull sacral neuromodulation. Show less
The initial damage recognizing complex in bacterial nucleotide excision repair consists of two UvrA and two UvrB molecules. Of these proteins UvrB is the main damage recognition protein and is... Show moreThe initial damage recognizing complex in bacterial nucleotide excision repair consists of two UvrA and two UvrB molecules. Of these proteins UvrB is the main damage recognition protein and is capable of recognizing various structurally unrelated types of damage. To do so, the protein must recognize a common alteration of the DNA structure induced by these different damages. For UvrB sterical hindrance of the present DNA modification prevents it from passing behind a _-hairpin structure present in the protein, thereby conferring damage recognition. Upon stalling of the protein at the site of damage in this way we show that two nucleotides become extrahelical: the nucleotide directly 3__ to the lesion and its base-pairing partner in the non-damaged strand. In contrast to other repair enzymes however the damaged nucleotide itself does not become extrahelical. Flipping in one of the two DNA strands has been shown to be important in preventing stable binding of the protein to undamaged DNA. Flipping in the other DNA strand however is required for efficient 3__ incision by UvrC, the nuclease of the system. A second incision at the 5__ side of the damage by the same protein facilitates removal of the damage-containing DNA oligonucleotide. Show less
The Rhetoric of Two Museums and the Representation and Canonization of Modern Art (1935-1975): The Stedelijk Museum in Amsterdam and the Museum of Modern Art in New York Museums of modern art have... Show moreThe Rhetoric of Two Museums and the Representation and Canonization of Modern Art (1935-1975): The Stedelijk Museum in Amsterdam and the Museum of Modern Art in New York Museums of modern art have determined the course of modern art history. Their contributions to the representation and canonization of modern art have been shaped by how they have presented art in their (temporary) exhibitions and publications. They have provided the public with a verbal and visual story of modern art. In order to provide greater insight into the process of the creation of the museums__ stories, this book uses __rhetoric__ to deconstruct their stories of modern art. Rhetoric is used as an analytical model to investigate the communications of modern art museums. Their goals are to communicate their stories and to persuade their various audiences of the importance of modern art. The principal strategies of classical rhetoric ethos, pathos and logos are used as the main entries for this book. Two influential museums are compared: the Museum of Modern Art (New York) and the Stedelijk Museum (Amsterdam). The differences in their goals, financing, audiences and positions in their societies, have determined their different persuasive strategies. By analyzing these museums as orators and deconstructing their verbal and visual rhetoric, the process of representation and canonization is clarified. Show less
A human consists of billions of cells. All these cells need to know in which organ they are located and what their position inside the organ is. One way to obtain this information is via morphogens... Show moreA human consists of billions of cells. All these cells need to know in which organ they are located and what their position inside the organ is. One way to obtain this information is via morphogens, small particles providing positional information. We quantitatively studied the transport of the morphogen Decapentaplegic (Dpp) in the __wing imaginal disc__ (the precursor of the wing) of fruit fly larvae. Certain cells in this disc produce Dpp, while others receive it and determine their position according to the Dpp concentration. To study Dpp transport we first developed a microscope able to follow single molecules in three dimensions in living tissue with high spatial and temporal accuracy. With this microscope we then studied the subcellular processes governing intracellular Dpp transport. We determined how long Dpp resides in different types of endosomes (a cellular compartment involved in transport). We also found that the movement of endosomes is too small to facilitate Dpp transport. Furthermore we found differences in the in- and outflow of Dpp in endosomes. This work is one of the first to quantitatively study intracellular morphogen transport. It provides new insights into growth and development of organisms. Show less
The theme of this dissertation relates to the perception of Russia as this is evidenced in European reflections on the Great Reforms in Russia during the period from 1861 to 1881, under the rule of... Show moreThe theme of this dissertation relates to the perception of Russia as this is evidenced in European reflections on the Great Reforms in Russia during the period from 1861 to 1881, under the rule of Tsar Alexander II. The Russian Empire had suffered a humiliating defeat in the Crimean War (1853-1856) by a coalition of modern Western powers. As a result, the Russian government felt compelled to introduce drastic reforms in order to modernise the country. The authorities sought to maintain the autocratic political system by incorporating elements borrowed from Western types of societies. This attracted a new generation of Western observers and researchers who strove for a more empiric factual knowledge and a more realistic understanding of Russia. Journalists and scholars spent several months, or even years, in Russia, learned the language, made personal contacts with Russians and studied official and unofficial sources to improve their knowledge of the contemporary situation. They also published their findings in the different countries of Europe, both in popular and in more scientific works. The images presented in these works ensured a certain demythologizing of Russia and contributed to the formation of a richer and more refined image of the Russians than previously. In this way, these works lay the foundation for the subsequent systematic and scholarly study of Russia . Show less
Cardiovascular disease is the principal cause of mortality in patients with type 2 diabetes mellitus. The present thesis describes a study, designed at a time-point when no primary prevention trial... Show moreCardiovascular disease is the principal cause of mortality in patients with type 2 diabetes mellitus. The present thesis describes a study, designed at a time-point when no primary prevention trial had yet been performed to investigate the effects of statin therapy on patients with type 2 diabetes without cardiovascular disease. We have performed a randomized, double-blind placebo-controlled trial in 250 type 2 diabetic patients without manifest cardiovascular disease. The aim of the study was to study non-invasively the effect of two year statin therapy on the vessel wall. We found no effect of two year statin therapy on carotid IMT as a reflection of the progress of atherosclerosis. We found no effect on endothelial function as assessed by FMD. The effect of statin therapy on CRP, as a marker for low grade inflammation, was only significant in a high- risk subgroup with the metabolic syndrome and a high LDL-cholesterol. There was no effect of two-year statin therapy on the prevalence of silent myocardial ischemia. In spite of these findings, we observed a lower cardiovascular event rate in patients on statin therapy, which is in line with other clinical trials. Show less
This dissertation provides a detailed analysis of the Chilean higher education system and policies over the period 1967-2007. It focuses on the creation, development and working of higher education... Show moreThis dissertation provides a detailed analysis of the Chilean higher education system and policies over the period 1967-2007. It focuses on the creation, development and working of higher education markets and policies. The approach employed is shared with other recent specialized market studies of terciary education, a field which has been formed academically during the last twenty years, based on the contributions of the organizational sociology of universities and the analysis of the political economy of markets. During this period, Chilean higher education unfolded in a changing political environment which is represented in this study by four episodes: first, the 1967 university reform, unleashed by the system__s own institutions, principally students; second, the intervention of universities in 1973 by the military government; third, the installation, by the same government, of a market policy for terciary education beginning in 1981; and last, the changes that have occurred since the recuperation of democracy in 1990. Each of these episodes illustrates a particular and specific form of organizing relations between the state and the higher education system; these are analyzed from the point of view of how the system__s coordination was structured with the shifting participation of government policies, institutional interests and market forces. Show less
This thesis discusses the dynamical properties of high redshift infrared selected and morphologically large disk selected galaxies at redshifts between 0.7 and 2.4 and their Tully-Fisher relations.... Show moreThis thesis discusses the dynamical properties of high redshift infrared selected and morphologically large disk selected galaxies at redshifts between 0.7 and 2.4 and their Tully-Fisher relations. Most observations were done using the near infrared integral field spectrograph SINFONI of the Very Large Telescope (VLT). Show less
This thesis is concerned with two research areas in natural computing: the computational nature of gene assembly and membrane computing. Gene assembly is a process occurring in unicellular... Show moreThis thesis is concerned with two research areas in natural computing: the computational nature of gene assembly and membrane computing. Gene assembly is a process occurring in unicellular organisms called ciliates. During this process genes are transformed through cut-and-paste operations. We study this process from a theoretical point of view. More specifically, we relate the theory of gene assembly to sorting by reversal, which is another well-known theory of DNA transformation. In this way we obtain a novel graph-theoretical representation that provides new insights into the nature of gene assembly. Membrane computing is a computational model inspired by the functioning of membranes in cells. Membrane systems compute in a parallel fashion by moving objects, through membranes, between compartments. We study the computational power of various classes of membrane systems, and also relate them to other well-known models of computation. Show less
The snails__ proverbial inertness makes it an ideal subject to study the patterns and processes that lead to speciation. The land snail family Chondrinidae consists of about 70 extant species in... Show moreThe snails__ proverbial inertness makes it an ideal subject to study the patterns and processes that lead to speciation. The land snail family Chondrinidae consists of about 70 extant species in six genera. They occur throughout western and central Europe, northern Africa and as far east as Pakistan. These snails share a long and interesting evolutionary history, to the knowledge of which we contribute here. Show less
In the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), a large population-based case-control study, we investigated lifestyle factors as risk... Show moreIn the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), a large population-based case-control study, we investigated lifestyle factors as risk factors for venous thrombosis. Overweight, smoking and alcohol consumption were addressed and pregnancy and the postpartum period were evaluated in women. Due to the large sample size of the study it was possible to investigate the joint effect of these risk factors with important genetic risk factors for venous thrombosis such as the factor V Leiden and the prothrombin 20210A mutation. In addition to these lifestyle related risk factors, two polymorphisms within the promoter region of the protein C gene were studied as risk factors for venous thrombosis and the influence of genotypic variation on plasma protein C levels was assessed. Finally, we described our experience with the inclusion of two different control groups in the MEGA study. Show less
Hox genes are a very important family of transcription factors during development of vertebrate and invertebrates. This family of genes contains up to 39 Hox gene members organized in 4 clusters in... Show moreHox genes are a very important family of transcription factors during development of vertebrate and invertebrates. This family of genes contains up to 39 Hox gene members organized in 4 clusters in the genome. The main function of Hox genes is the establishment of the anteroposterior axis of the embryo. During gastrulation of the frog Xenopus laevis, Hox genes start to be expressed in the mesoderm excluding the Spemann organizer mesoderm. However, a necessary interaction between the involuting mesodermal cells and the signals from the Spemann organizer center freeze the pattern of Hox expression at that time point. Thus a temporal Hox expression is converted into a spatial Hox expression during development. Moreover, Hox gene expression within the mesoderm seems to be important for Hox expression within the neural tissue. We missexpressed several Hox genes and analyzed their phenotype within the hindbrain and more posterior neural tissue. Paralogous 1 group Hox genes are important for globally pattern the hindbrain, while Hoxc6 gene seems to very important during neurogenesis in Xenopus. Axis elongation and segmentation are liked processes during development. We showed that Hoxc6 is an important gene for proper segmentation of Xenopus embryo. Show less
