Tissue Structure Analysis in Urological Dysfunctions

Congenital urethral valves and a dysfunctional sphincter after spina bifida are the two major causes for a partial urethral obstruction in children, causing bladder dysfunction. The aim of this study is to find a solution to get this insight in the development of bladder damage and the further course of bladder functional development during and after intervention. This thesis describes two main research lines: the first investigates the correlation between bladder function and bladder structure, paying particular attention to the role of ischemia. An animal model was used that allowed us to simulate a partial obstruction of the urethra and monitor changes in bladder function over time. We have found a relationship between the severity of ischemic periods, characterized by the number of glycogen deposits, and the level of functional changes. The second main study outline was to apply determination of glycogen deposits in a clinical set up and in a non-destructive manner, thus without the need for biopsies. For this we studied the possibilities of Raman spectroscopy. In vitro Raman spectroscopy was successfully used to determine structural changes in ! tissue sections in a non-destructive manner and it initiated the study for the scoring of glycogen granules related to bladder function. Additionally, bladder tumor and non-tumor tissue areas were successfully discriminated with Raman mapping. Spectral analysis revealed the compositional basis for this. The techniques used and findings presented in this thesis are the basis for further research in order to develop the scoring of glycogen deposits as a measure for historic bladder function into a clinical application

Screening disability insurance applications

This paper investigates the effects of stricter screening of disability insurance applications. A large-scale experiment was setup where in two of the 26 Dutch regions case workers of the disability insurance administration were instructed to screen applications more stringently. The empirical results show that stricter screening reduces long-term sickness absenteeism and disability insurance applications. We find evidence for direct effects of stricter screening on work resumption during the period of sickness absence and for self-screening by potential disability insurance applicants. Stricter screening seems to improve targeting efficiency, without inducing negative spillover effects to the inflow into unemployment insurance. The costs of stricter screening are only a small fraction of the monetary benefits.Disability insurance; experiment; policy evaluation; sickness absenteeism; self-screening

Modeling CLV:A test of competing models in the insurance industry

Customer Lifetime Value (CLV) is one of the key metrics in marketing and is considered an important segmentation base. This paper studies the capabilities of a range of models to predict CLV in the insurance industry. The simplest models can be constructed at the customer relationship level, i.e. aggregated across all services. The more complex models focus on the individual services, paying explicit attention to cross buying, but also retention. The models build on a plethora of approaches used in the existing literature and include a status quo model, a Tobit II model, univariate and multivariate choice models, and duration models. For all models, CLV for each customer is computed for a four-year time horizon. We find that the simple models perform well. The more complex models are expected to better capture the richness of relationship development. Surprisingly, this does not lead to substantially better CLV predictions

The influence of learner-generated domain representations on learning combinatorics and probability theory.

The aim of the current study was to examine the effects of providing support in the form of tools for constructing representations, and in particular the differential effects of the representational format of these tools (conceptual, arithmetical, or textual) in terms of perceived affordances and learning outcomes. The domain involved was combinatorics and probability theory. A between-subjects pre-test–post-test design was applied with secondary education students randomly distributed over four conditions. Participants completed the same tasks in a simulation-based learning environment. Participants in three experimental conditions were provided with a representational tool that could be used to construct a domain representation. The experimental manipulation concerned the format of the tool (conceptual, arithmetical, or textual). Participants in a control condition did not have access to a representational tool. Data from 127 students were analyzed. It was found that the construction of a domain representation significantly improved learning outcomes. The format in which students constructed a representation did not directly affect learning outcomes or the quality of the created domain representations. The arithmetical format, however, was the least stimulating for students to engage in externalizing their knowledge

Predicting Customer Lifetime Value in Multi-Service Industries

Customer lifetime value (CLV) is a key-metric within CRM. Although, a large number of marketing scientists and practitioners argue in favor of this metric, there are only a few studies that consider the predictive modeling of CLV. In this study we focus on the prediction of CLV in multi-service industries. In these industries customer behavior is rather complex, because customers can purchase more than one service, and these purchases are often not independent from each other. We compare the predictive performance of different models, which vary in complexity and realism. Our results show that for our application simple models assuming constant profits over time have the best predictive performance at the individual customer level. At the customer base level more c

A split-cavity design for the incorporation of a DC bias in a 3D microwave cavity

We report on a technique for applying a DC bias in a 3D microwave cavity. We achieve this by isolating the two halves of the cavity with a dielectric and directly using them as DC electrodes. As a proof of concept, we embed a variable capacitance diode in the cavity and tune the resonant frequency with a DC voltage, demonstrating the incorporation of a DC bias into the 3D cavity with no measurable change in its quality factor at room temperature. We also characterize the architecture at millikelvin temperatures and show that the split cavity design maintains a quality factor $Q_\text{i} \sim 8.8 \times 10^5$, making it promising for future quantum applications