Academic Ceremonies April 2009

“Psychoacoustic and neurophysiologic Investigations of auditory continuity”

Our capability to track sounds in noisy environments is illustrated by the continuity illusion in which an interrupted sound is perceived as uninterrupted, provided that another sound masks the interruption. The present studies combine methods (psychoacoustics, functional magnetic resonance imaging, electroencephalography) to reveal the underlying constructive mechanisms in the human brain. The results identify i) acoustic, cognitive, and contextual factors, ii) brain regions, and iii) time intervals of neural processing which are critical for producing the illusion. The results put forward a neural-computational model that may be implemented in artificial devices to restore smooth hearing in noisy environments.

Key words:

auditory, hearing, fMRI, EEG

“Use of non-pathogenic bacteria as vectors for targeted gene expression in cancer gene therapy”

“The clinical value of TURP in patients with elevated or rising PSA”

For the diagnostics of prostate disorder PSA (prostate specific antigen) is an important cornerstone. However, the big limitation of PSA is the fact that this test is only organ specific (prostate) and not cancer specific. Patients with a rising PSA level form a growing population in the urologists’ practice. This dissertation shows that in patients with risen PSA without demonstrable prostate cancer an ‘asymptomatic’ infravesical obstruction (i.e. urinary obstruction) caused by a benignant prostate enlargement should be considered. Removing this obstruction by means of keyhole surgery (TURP) will lead to a supernormal PSA level and symptomatic improvement in most patients and above all, in most cases no cancer will be found.

Key words:

prostate disorder, cancer, PSA.

“Functional and structural brain markers of Alzheimer’s disease: clinical studies using EEG and VBM”

“Mental slowness after stroke: assessment and treatment”

One of the most common cognitive disorders after a stroke is slowness of information processing. This dissertation focuses on the limitations the patient experiences in everyday activities (following quick conversations, doing two things at the same time and reacting adequately) and on the related consequences such as fatigue. The effects of the Time Pressure Management training, where patients learn to adequately deal with the consequences of their slowness, are evaluated. After the training the patients have fewer complaints and they are able to perform everyday tasks quicker without making more mistakes. The Time Pressure Management training turns out an effective method for dealing with the consequences of slowness of information processing.

Key words:

stroke, slowness of information processing, cognitive revalidation.

“The impact of Ankylosing Spondylitis on bone”

Ankylosing Spondylitis (AS) is a form of chronic, rheumatic inflammation particularly in the vertebral column (spondylitis). In patients this leads to chronic back pain, stiffness in the back and ultimately to growing together of the vertebra (ankylosing). One of the conclusions of the research is that in patients with Ankylosing Spondylitis the bone and vertebra quality has deteriorated to such an extent that they run a three times higher risk of vertebral fracture. Two-thirds of these patients experienced permanent neurological damage as a result of that. Furthermore, the research studied if hyperkyphosis (curving of the vertebral column) can be measured and predicted. It turns out that three factors jointly predict the curving: the activity of the disease, the degree of syndesmophyte formation (the bone hooks that bind the vertebra together) and the wedge formation (collapsing of the vertebra).

“Preparing for action; a behavioral and pupillometric study”

“Differentiatie in het (Europees) contractenrecht”. (‘Differentiation in (European) contract law.’)

This research studies among others the question if contact law should be designed around a general contract law, formed by the foundations and principles that apply to all agreements and contact parties, or if this idea should be dismissed as useless and a choice should be make for a differentiated contract law. For this purpose the author surveys among others arguments for and against a differentiated contract law. Also various doctrines of contract law are studied. 

Key words:

contract law, private law.

“Different kinds of Precaution; a comparative anaylsis of the apllication of the precautionary principle in five different legal orders”

The thesis has outlined the application of the precautionary principle in international and EC law, as well as compared the application of the principle in the fields of pesticide regulation and mobile telephony in Sweden, the United Kingdom and the Unites States. The principle implies that there is a responsibility to intervene and protect the public from exposure to harm in the absence of a scientific consensus. The study has shown that the principle at present often is applied in an inconsistent and inefficient manner. Similar situations are often treated differently by regulators and effective redress before the courts is severely limited. It is suggested that a rational legal framework for the application of precautionary decisions is elaborated, on the national as well as the EU and international levels. 

“Earning-by-learning”

Firms increasingly rely on external partners (i.e. consumers or firm partners) to execute services. Examples of such services are makelaarsland.nl or online investment sites. Because of inexperience or lack of knowledge problems can sometimes arise in the cooperation. This dissertation offers three empirical studies, focused on improving the performance of the consumer or partner. By offering information or via training companies can improve the performance of their customers and partners. This is done directly by improving the skills and increasing the knowledge, but also indirectly by increasing the task-specific confidence of customers (self-efficacy) or increasing the knowledge application. The research focuses on these indirect factors. Based on the findings, the dissertation offers suggestions and guidelines to companies for offering information and training. 

“Myocardial Infarct Healing: Rupture and remodeling”

The process of wound healing after a myocardial infarct is very complicated and can cause various complications. This dissertation studies two frequent complications, namely infarct rupture and heart failure. Infarct rupture, a rupture in the infarct, appeared to be related to a defect in the so-called cell adhesion complex that connects the heart muscle cells with each other. By means of imaging techniques heart failure could be predicted by registering the amount of myofibroblasts, a cell type that occurs in the infarct area. As soon as this imaging technique will be clinically applicable optimal treatment can be applied in high risk patients, so that heart failure after a myocardial infarct can possibly be prevented. 

Key words:

myocardial infarct, heart failure, imaging technique

“Anytime, Anyplace, Anywhere: Kennismanagement in de platte wereld”

“Graphs, Mechanisms and Scheduling”

Traditional optimization among others deals with scheduling problems, such as assigning tasks to machines in a production process. Although most models assume the presence of a central planner, there are usually several agents who have to cooperate with each other. This dissertation studies the mechanisms that organize the cooperation in such a way that good solutions for the scheduling problem can be reached, even if the agents act selfishly. A solution is ‘good’ if for example the total satisfaction of all agents or the profit of the machine’s owner is as big as possible.

Key words:

mechanism design, scheduling, optimization, online optimization, revenue equivalence.

“Zo kan het ook. Een ander perspectief op organisatiewetenschap”.(‘Another way to do it. Another perspective on organization science.’)

“New insights in the Surgical Treatment of Chronic Ischemic Mirtral Regurgitation”

The malfunction (regurgitation) of the heart’s mitral valve complicates a high percentage of myocardial infarctions. This condition requires cardiac surgery and it still represents a serious challenge for surgeons. The intervention consists of a coronary artery bypass, performed to ensure blood supply to diseased coronary arteries, associated with a repair of the native mitral valve. Nonetheless, after few years, the repair fails and, as a result, the mitral disease re-appears in the major part of patients. Our research gives new insights in the surgical treatment of this pathology and makes an attempt to identify, before surgery, patients who can really benefit from this approach.

Key words:

hart; hartinfarct, hartchirurgie

“Role of infections on intimal hyperplasia”

After treatment of atherosclerosis blood vessels often clog up again because of an increase in the number of smooth muscle cells in the vascular wall (“intimal hyperplasia”). In various animal models the role of the bacteria Chlamydia pneumoniae and the cytomegalovirus (CMV) in intimal hyperplasia was studied. We also tried to prevent the closing up of the blood vessel by means of gene therapy. Our results show that C. pneumoniae and CMV play a role in vascular wall thickening in experimental animal models of percutaneous angioplasty and bypass operations. However, after organ transplantation no link could be shown between C.pneumoniae and this disease. C.pneumoniae and CMV infections are capable of stimulating smooth muscle cell proliferation, even if there were only few micro-organisms present in the vascular wall. We also showed that the new medicine FK778 is functional in the prevention of excessive vascular wall thickening. Finally gene therapy turned out a successful way of decreasing intimal hyperplasia in our animal model.

“MS: en hoe verder ?” (‘MS: how further?’)

“Microfinance – Greater good or lesser evil”

The major objective of this dissertation was to get a deeper understanding of a special intervention designed to bring out the greater good in microfinance in India. To do so, Augsburg conducted a household survey in rural India of approximately 500 participants and 500 non-participants of this intervention. This led to the conclusion that the intervention plays a crucial role in consumption smoothing of the household and that it has the potential to lift participants above the poverty line. This effect is stronger for those participants who additionally have non-financial services, which points to the importance of taking an integrated approach to microfinance when it comes to the very poor.

Key words:

microfinance, India

“Ecological aspects of cognitive assessment”

Worldwide, there is an increase in the number of people with neurological disorders such as non-congenital brain damage and dementia (respectively  by 12% and 66% between 2005 and 2030). These neurological disorders often lead to difficulties in everyday life, not only in the physical area, but also in the neuropsychological area, such as cognition, emotion and behaviour. Bouwens’ research shows that the cognitive functioning, measured in a test environment, deviates from the functioning in everyday life. The relation between cognition and daily life depends among others on the type of dementia and in people with a non-congenital disorder the observation of people in their own environment produces important additional information that is not revealed in neuropsychological tests. One of the conclusions is therefore that the relation between cognition and everyday functioning can be used as a diagnostic instrument. 

Key words:

non-congenital brain damage,  dementia, cognitive research, everyday life