Academic Ceremonies April 2011

“Persistent Risk Factors in Financial Markets”

Many risk factors in financial markets, such as the short-term interest rate, the yield spread, the rent to price ratio, or conditional stock market volatilities, exhibit strong temporal dependence. Financial theory suggests that investors care about risk and adjust their return expectations accordingly. Hence, it is important for market participants to understand the duration of shock impacts, as it determines the length of the time period during which expected returns remain low (or high) on average. We focus on the implications of persistence in financial risk factors on empirical asset pricing. Capturing the strong temporal dependence in risk factors with long-memory models, we develop a generalized model for bond yields and find that risk premiums of excess bond returns are very persistent and that positive news about the short-term interest rate imply a negative adjustment of expected excess returns. We further investigate the consequences of persistent risk factors in the real-estate and the stock market. We show that when properly accounting for this temporal dependence, one can find strong evidence in favor of return predictability, a positive risk-return trade-off, and the present-value relation of prices and fundamentals.

Key words:

financial risk and return, time-series persistence

“The Nε- (Carboxymethyl)lysine-RAGE axis; Implications for the pathogenesis of obesity-related complications”

As the number of people with obesity increases, the number of people with type 2 diabetes and diabetic complications, such as cardiovascular diseases, also rises.  An important mechanism that explains the increased risk of type 2 diabetes and cardiovascular diseases in obese people is the release of inflammatory substances from the fatty tissue, which subsequently causes chronic inflammation reactions. An important question is which factors provoke the fat cells to produce these inflammatory substances. This research shows that the glycated protein N-(Carboxymethyl)lysine (CML) accumulates in the fatty tissue of obese people and stimulates the fat cells to produce inflammatory substances. The discovery that CML plays an important role in the development of inflammatory substances in the fatty tissue offers new perspectives for the development of therapeutic interventions that can prevent the emergence of type 2 diabetes and cardiovascular diseases in obese people. 

Key words:

obesity, type 2 diabetes, cardiovascular diseases, CML, treatment

“Working Together: Theories and Thoughts on Collaborative Capital”

“De drie musketiers zijn inmiddels meer geworden”

“Dietary interventions and intestinal defence to protect against salmonella infection”

Intestinal infections are still a world-wide problem, also due to the increase of antibiotics resistance in the pathogenic agents. This dissertation describes how the defence against one of the main pathogens, Salmonella, can be increased with certain food components. A supplement of di-peptide cystine or a polyphenol turned out to inhibit infection induced diarrhoea and to lower the intestinal permeability during a Salmonella infection in pre-clinical studies. Possibly these food components also increase the defence of people, but this should be further investigated. Moreover, a new and promising biomarker, the protein PAP, was identified. By means of measurements in a faeces sample this allows to monitor the intestinal defence in man. 
This PhD research was conducted at NIZO food research, commissioned by TI Food and Nutrition.

Key words:

intestinal infection, intestinal defence, nutrition, polyphenol, cystine, biomarker

“Cold and diet induced thermogenesis in humans; Implications for obesity”

Both exposure to cold and an increased food intake lead to an increase of the energy use, the so-called adaptive thermogenesis.  After exposure to cold, this mechanism effects that a person becomes hypothermic less quickly and after overnutrition it brings about that less food substances are stored in the body. However, there are important differences between persons in this response. Some do not, or hardly, increase their energy use, others even up to 15 per cent. Persons with a healthy weight averagely increase their energy use, whereas people with obesity don’t. This metabolic reaction to cold is connected with the reaction to overnutrition: someone who increases his energy use when he is exposed to cold, also does this in the case of overnutrition. The difference in this response is explained by mitochondrial disconnection in the skeleton muscle: in not obese people the available energy in the mitochondria (energy stations) is not only used for the cellular metabolism (turnover of ADP into ATP), but also for the production of warmth. Obese people use less energy and therefore produce less warmth. The not used energy is stored as fat. 

Key words: 

energy use, thermogenesis, obesity

“Triggers for energy expenditure: thermogenic ingredients & circadian aspects”

The current increase in overweight and obesity are the consequence of an imbalance in energy expenditure and energy intake. This dissertation shows that besides limitation of the food intake it is necessary to stimulate the energy expenditure with natural ingredients. These ingredients (such as green tea blended with a little caffeine, protein diets, caffeine and capsaicin) can be part of the daily nutrition. The results show that green tea blended with a little caffeine raises the energy use and the fat oxidation and can be used to realize weight loss and weight maintenance. Protein diets also increase the energy expenditure, particularly proteins with a higher concentration of essential amino acids. These proteins also realize a stronger effect of hunger suppression. When green tea/caffeine and protein are administered at the same time, there is no amplified effect. The dissertation also shows that after fragmented sleep the carbohydrate oxidation is raised and the fat oxidation lowered, and the first signs of decreased insulin sensitivity became visible. This means that too little or disturbed sleep can underlie overweight because of a disturbed homeostasis. 

Key words:

obesity, energy expenditure, green tea/caffeine blend, protein, fat oxidation, sleep

“Clinical and molecular genetic studies in hereditary cutaneous leiomyomatosis”

“Tuberculosis in India; a case of innovation and control”

India is the country with the highest number of Tuberculosis patients. This thesis draws on innovation studies and Science and Technology Studies to examine innovation dynamics in organizational, strategic, technological and service delivery aspects of public Tuberculosis control in India. The results reveal that the dynamics of innovation and control in coping with Tuberculosis in India are a complex interplay of mutual influence and requirement. This is often disregarded by actors in the field. Controlling for example every aspect of a diagnostic process through standardization can exclude local scientific and non-scientific expertise and as a result face challenges in the field. Yet, innovating a diagnostic test without standardizing operational processes is not feasible for the TB programme and will fail to be taken into consideration by the decision-makers. The mechanism that would need to be fostered to strengthen innovation capacities are situated assessments of the relation between different practices of innovation and control.

Key words:

Tuberculosis, healthcare innovation, India

“Modulation of the neuroinflammatory response after spinal cord injury”

“Optimal experimental designs for functional magnetic resonance imaging”

Before performing a functional magnetic resonance imaging (fMRI) experiment, a researcher needs to decide on the number of persons (subjects) to be scanned and on the duration of their scanner sessions. Furthermore, the order and timing of the considered stimulus types have to be chosen to present them during the subject’s scanner session. This thesis evaluates the influence of several experimental factors on the efficiency and costs of fMRI experiments. One major result is a method to determine the optimal number of subjects and optimal scanner session length for a certain type of fMRI experiments, i.e. blocked designs. It is seen that commonly employed numbers of subjects (10-20) are too low in certain cases. Another interesting result is that the optimal length of stimulus blocks in a blocked design is slightly shorter than previous recommendations.

Key words:

functional magnetic resonance imaging (fMRI), optimal design

“Constructing Agrarian Alternatives; how a creative dissent project engages with the vulnerable livelihood of marginal farmers in South India”

“Uncoupling protein 3 and the protection of skeletal muscle mitochondrial function; a transgenic approach”

Mitochondria are the power stations of the cell.  They make energy out of carbohydrates and fats from nutrition and are therefore essential for life.  However, mitochondria also make oxygen radicals that can lead to damage to DNA, proteins and fats, and are involved in the ageing process and the possible development of diabetes and cardiovascular diseases. In this dissertation we studied if the mitochondrial uncoupling protein 3 (UCP3), mainly  present in the skeletal muscle and the heart, plays a role in the protection of mitochondria against these oxygen radicals. The results from the studies described in this dissertation provide independent and convergent evidence that UCP3 does indeed play a role in the regulation of the mitochondrial oxygen radical production. Further research will be necessary to show the involvement of UCP3 in the ageing process and the development of diabetes and cardiovascular diseases.

Key words:

mitochondria, oxygen radicals, UCP3

“Was het maar zo makkelijk”

“Beter in Beweging”

“Capital Allocation and Non-Cooperative Behavior in Diversified Firms”

Diversified firms that comprise several business activities play a central role in all major economies across the world. An important issue among these firms is how to allocate capital among their distinct businesses for large-scale investments, e.g. the construction of a new production site. This dissertation analyzes these internal capital allocation processes, how inefficiencies can arise through non-cooperative behavior of managers and how these inefficiencies can be resolved. More specifically, this dissertation provides evidence that firms can improve the efficiency of their internal capital allocations either by adjusting the compensation contracts of these managers or alternatively by rearranging the organizational design of their business units. Furthermore, it is examined how delegating authority over investment projects within the firm affects the way in which managers renegotiate the initially requested capital budget to their own advantage. Apart from extending academic knowledge about internal capital allocations, this dissertation provides important insights for practitioners who seek to improve capital allocations or who need to evaluate the allocation efficiency of diversified firms, for instance during mergers and acquisitions.

Key words:

diversified firms, capital allocations, behavior of managers 

“Redesigning dementia care; an evaluation of small-scale, homelike care environments”

Small-scale residential homes are strongly emerging in nursing home care for elderly people with dementia. Experiences are mostly positive compared to traditional nursing home care. The present dissertation, however, shows a differentiated picture of the effects of small-scale living on the residents, their caretakers and employees. Contrary to expectation the quality of life of residents in small-scale residential homes does not differ from that of comparable residents in traditional nursing homes with wards of at least 24 persons. Between both groups no differences were found in neuropsychiatric symptoms and turbulence. The work satisfaction and motivation of employees don’t show differences either. The involvement of family members of residents in small-scale residential homes does not differ from traditional wards.  Family members of residents from small-scale residential homes show a lower care load and are more satisfied with the care. A complete change to small-scale residential homes is therefore not obvious.

Key words:

dementia, nursing home care, small-scale residential homes