Academic Ceremonies March 2013

“Unified yet separated; Empirical Study on the Impact of Hierarchical Positions within Communities of Learning”

Communities of Learning (CoL) are promoted to foster interpersonal knowledge transfer among participants of organizational training initiatives. However, past research has largely neglected hierarchical positions as a major obstacle to collaborative learning processes. Yet, in practice, evidence has shown that top management will exhibit a drive to dominate discussions and reinforce the prevailing status quo, while lower level management often has been found to face a certain fear of speaking up in front of their supervisors. This dissertation addresses this shortcoming by providing empirical evidence from 25 CoL of a global organization. The results clearly indicate that the higher participants’ hierarchical position, the higher their level of activity and the higher their performance. By incorporating these insights into future CoL, HRD managers can better design and facilitate collaborative learning activities that contribute to the learning experience of all participants, e.g. implement a mentoring system or instruct facilitators to pro-actively connect participants.

Key words:

communities of learning, learning process, hierarchical position

“Neurodevelopmental toxicity detection by transcriptomics in an embryonic stem cell differentiation assay”

For research into the possible harmfulness of chemical substances and medicines for fertility and the unborn child many laboratory animals are used. This dissertation describes the use of embryonic stem cells in a new test without laboratory animals, in which the effects of substances on the formation of nerve cells can be determined. The research focuses on the use of changes in gene expression as a measure for the effects of substances, and determines at the same time with the help of the ‘transcriptomics’ technique the gene expression of all genes. Substance-specific changes in gene expression appear to have predictive value for the harmfulness of the substances for the unborn child. This research makes an important contribution to both knowledge about mechanisms of harmfulness of substances and to the reduction of laboratory animal use in developmental toxicology.

Key words:

toxicity, embryo, stem cell test, ‘transcriptomics’

“Deep brain stimulation and the cerebellum”

“Lipid droplet coat proteins, skeletal muscle lipid metabolism & insulin sensitivity”

Steatosis in muscles plays an important role in the development of insulin resistance, an obesity-associated early stage of type 2 diabetes.  However, also endurance trained athletes show a high degree of fat storage in the muscles, even though athletes are in fact highly insulin sensitive. This suggests that not the extent of fat storage but the characteristics and localisation of this muscle fat determine whether it disturbs the insulin signal cascade.   
This dissertation shows that the muscle cells of type 2 diabetes patients have an intrinsically reduced capacity for the neutral storage of fats in lipid droplets. Moreover, it was shown that the creation of storage capacity for neutral lipids protects against obesity-associated insulin resistance in the muscle.  In rats, increasing the presence of the lipid droplet proteins perilipin 2 (PLIN2) or PLIN5 in the muscle led to an increased fat storage in lipid droplets without negatively influencing the insulin sensitivity of the muscle. Further research into interventions that positively influence the PLIN function and consequently the fat storage capacity – such as pharmacological, nutritional and exercise strategies – are therefore promising in the framework of prevention and treatment of type 2 diabetes. 

Key words:

type 2 diabetes, muscle, lipid metabolism, fat, obesity.

“Lifestyle and arterial stiffness in young adults: A life-course approach”

“Electronic mobility aids for persons who are visually impaired”

Persons who are severely visually impaired or blind can use, besides the well-known ‘white cane’ or a guide dog, Electronic Mobility Aids (EMA) to move independently outdoors. These aids offer support with obstacle detection, orientation and navigation. This dissertation gives an overview of available EMA and provides insight in their usability, functionality and effects on the mobility of the user. For measuring the usability and functionality, and for measuring the effects new methods were developed. Based on the results of the research an advisory protocol has been developed for the supply of EMA in practice. This has been implemented in organisations that provide care for the blind and the visually impaired. 

Key words:

visual impairment, blindness, Electronic Mobility Aids (EMA)

“Enhanced Prediction and Prevention of Drug-Induced Torsades de Pointes”

Over the last decades, drug induced cardiac arrhythmias, including Torsades de Pointes (TdP) have become a major issue in drug development. There is a pressing need for better understanding of the mechanisms involved in TdP manifestation to allow for enhanced prediction (via more predictive surrogate markers) and prevention of this arrhythmia (via novel targets). This thesis elucidates a number of cellular mechanisms involved in beat-to-beat variability of repolarization, which is one of the newer surrogate markers thought to have utility in predicting this arrhythmia. The thesis highlights the role of calcium release from the calcium store within the single myocyte in altering this parameter. Additionally the dissertation illustrates the link between mechanical and electrical activity under specific conditions and provides further validation of an additional novel marker for proarrhythmia (the electro-mechanical window). Finally, research contained within this thesis suggests antiarrhythmic strategies for the development of novel therapeutic agents.

Key words:

cardiac arrhythmias, drug development, cellular mechanisms, markers

“Novel Perspectives in Regulation of Chondrogenic Differentiation”

The joints contain cartilage that allows them to move swiftly. When cartilage is damaged by a trauma or osteoarthrosis, this often difficultly recovers. This research wants to find new ways to stimulate cartilage formation from stem cells and to prevent undesired ossification. It is shown that a short and very mild inflammatory reaction (as in a wound healing process) is capable of stimulating cartilage formation, that physiological environmental factors of cartilage play a regulatory role in the cartilage formation process, and that the medicine celecoxib can prevent ossification. These results contribute to the optimization of cartilage regeneration techniques.  
This research was co-financed by the Reumafonds and the Annafonds.

Key words:

cartilage, regenerative medicine, stem cells, osteoarthrosis and orthopaedics

“OLD TIMES AHEAD; The Dawn of the Ageing Consumer”

In ageing Western societies older people become increasingly important for companies’ sustained success, because older people form a big and attractive market segment. This PhD research shows that the prevailing stigma of older people being poor, frail and old-fashioned, is often incorrect – many 50plus consumers are healthy, wealthy, active and curious.  In order to serve the older consumer appropriately, companies and researchers need to understand what characterizes the older consumer. For example, older people base their decisions on their experiences and they consider fewer alternatives than younger people. Older consumers are also more reluctant to believe ad claims than younger consumers. This information helps marketers in their communication strategies.

Key words:

50plus consumers, characteristics, marketing strategy

“The Triple Burden of War; an assessment of the mental health status and coping strategies of Sudanese female undergraduates for developing a psycholsocial counselor training program”

The current Darfuri crisis and the associated mental health burden have warranted the investigation into the mental health status of two groups of Sudanese female undergraduates: War-affected Darfuri and non-war-affected Omdurmani.
Darfuri female undergraduates had high levels of emotional distress that were strongly associated with the prevalence and severity of post-traumatic stress disorder, whereas Omdurmani students faced the ‘normal’ tertiary challenges of undergraduate life. However, both student groups showed similar levels of major depression disorder and generalized anxiety disorder.
Resilience levels and coping strategies differed; Strong religious practices, the ability to form interpersonal relationships and a positive future outlook seemed to lend to Darfuris the ability to cope. Omdurmanis however were more likely to use leisure activities, were more self-reliant and preferred being alone. This research will be used to design a culturally relevant war-trauma counsellor training program that can be used by educational institutions throughout Sudan.

Key words:

vrouwen, copingstrategieën, oorlogstrauma, opleiding voor adviseur

“Institution and Corporate Governance”

“Integrated Chronic Care for Patients with Atrial Fibrillation”

“Brain in Sight: probing the neural dynamics Underlying conscious vision”

Which processes in the human brain are responsible for conscious vision? The visual system consists of several areas that each play a certain role in the representation of our perception. This research used several methods to study this large network at various levels. Magnetic stimulation of visual brain areas, for example, was used to disturb perception, brain scans were used to examine the communication in the brain during visual tasks, and new experimental manipulations offered insight in fundamental interactions between information streams of our two eyes. Integration of these different perspectives is necessary to realize a complete picture.

Key words:

vision, brain

“Doorbreking van de natrekking: in rechtsvergelijkend perspectief”

“Van paradox naar behandeling: het oude renine-angiotensine systeem in een nieuw licht”

“Screening for hepatitis C virus infection of individuals at risk hidden among the general population”

“The glutaredoxin 1/protein S-glutathionylation axis in inflammatory lung disease; in vitro to clinical characterization”

“Intranasal delivery of rapid acting drugs”

“Pien, douleur of schmerz?”

“Bot en afweer: partners of rivalen?”

“Encoding of natural sounds in the human brain”

In everyday life, we are surrounded by sounds that convey language, emotion, and other vital information regarding our environment. This thesis describes studies that use functional magnetic resonance imaging (fMRI) to investigate how incoming sound waves are processed in the human brain. The results show that throughout the human brain multiple orderly representations of sound frequency (tonotopic maps) exist. Furthermore, neuronal populations are finely tuned to combinations of behaviourally relevant frequency bands. This selective tuning may reflect neuronal filtering mechanisms operating to transform tonotopic sound images into higher-level, behaviourally relevant representations.

Key words:

natural sounds, fMRI, human audition, tonotopic maps 

“Assessing outcomes of liver surgery: current status and future prospects”

Atrial fibrillation (AF), a common cardiac arrhythmia, is a chronic disorder. This research studied the effectiveness of an integrated approach of this patient group:  an outpatient clinic for patients with AF (AF outpatient clinic), under the direction of nurses, based on guidelines and supported by software.  
A randomized scientific study among 712 AF patients (comparison of AF outpatient clinic and regular care) showed a significant improvement of compliance with evidence-based guidelines, which resulted in a significant reduction of cardiovascular hospitalizations and mortality in the AF outpatient clinic in comparison to regular care. Moreover, this approach is cost-saving.  Practically speaking, this extensive intervention, aimed at patient information, guidelines and teamwork is the key to success. The results confirm the statement that an integrated approach of chronic care can prevent future capacity problems and extremely high costs.

Key words:

chronic care, integrated approach, atrial fibrillation

“Vitamin D and Multiple Sclerosis: immunological and clinical outcome”