Assessment to optimise postgraduate medical training

Scheele, F. [Promotor]Braat, D.D.M. [Promotor]Schuwirth, L.W.T. [Promotor

Systemic treatment effectiveness in advanced esophagogastric cancer in clinical practice

This thesis includes studies that focus on the palliative treatment of patients with advanced esophageal and gastric cancer in daily clinical practice. Rather than curation, palliative treatment aims to prolong survival, optimize quality of life and reduce symptom burden. Most results regard palliative systemic treatment, which consists of either chemotherapy, targeted therapy or both. This thesis provides insights into the management of patients with advanced esophagogastric cancer in The Netherlands using data of the nationwide Netherlands Cancer Registry, supplemented with patient-reported outcomes of the Prospective Observational Cohort Study of Oesophageal-gastric Cancer Patients (POCOP). It sheds light on several factors that are associated with the allocation of palliative systemic treatment, e.g. gender, but also factors that are not patient or tumor-related, e.g. the number of patients diagnosed in a hospital annually. Practice variation in first-line and second-line palliative systemic treatment administration as well as in biomarker testing is described. Moreover, aspects that are associated with treatment outcomes, such as skeletal muscle mass and cachexia, are discussed. The real-world results provide an overview of the contemporary situation of palliative systemic treatment administration in esophagogastric cancer in clinical practice, and enabled to reveal differences between treatment effectiveness in clinical practice and treatment efficacy described in clinical trials

Monitoring driver’s mental workload for user adaptive aid

Gebruikers-adaptieve machines gebruiken sensortechnieken en computer algoritmes om interne toestanden van de gebruiker af te leiden en beslissingen te nemen op basis van deze informatie. Toekomstige generaties auto’s zouden hiermee in staat kunnen worden gesteld actie te ondernemen indien de rijcapaciteit van de bestuurder suboptimaal wordt tijdens het autorijden, zelfs voordat de rijprestatie noemenswaardig verslechtert. De grote uitdaging van zo’n ondersteuning is dat het automatisch, onmiddellijk en op individueel niveau informatie moet kunnen interpreteren, terwijl dit individu beïnvloed wordt door hetzelfde systeem. Mijn proefschrift was gericht op deze uitdaging, waarbij de focus is gelegd op mentale inspanning.In hoofdstuk drie wordt betoogd dat een betrouwbaar systeem waarschijnlijk meerdere typen informatie nodig heeft om de interne toestand vast te kunnen stellen, zoals rijgedrag, fysiologie, en subjectieve ervaringen. Het belangrijkste inzicht uit hoofdstuk vier is dat gebruikers de ondersteuningsacties van adaptief systeem als waarschuwingssignaal kunnen gebruiken, en daarmee het systeem anders gebruikten dan bedoeld. In hoofdstuk vijf werd gekeken naar de mogelijkheid automatische muziekselectie in te zetten teneinde mentale inspanning te beïnvloeden, maar een direct verband tussen inspanning en muzieksoort werd niet aangetoond. In hoofdstuk zes werd de stap gemaakt naar individuele data-analyses uit hersengolven, met zeer goede classificatie resultaten. Uiteindelijk leidde dit tot een op hersengolven gebaseerde cruise control die tijdens (gesimuleerd) autorijden de mentale inspanning van de bestuurder classificeerde, terwijl de rijprestatie ook gemonitord werd (hoofdstuk zeven). Hieruit bleek dat vervolgonderzoek zich zou moeten richten op het verbeteren van de monitorbetrouwbaarheid door het verlagen van de tijds- en contextafhankelijkheid.User adaptive machines use sensor technology and computer algorithms to infer the user’s internal state and make decisions based on this information. Future cars could use this technology to intervene if the capacity of the driver to drive safely is degraded, even before performance starts to break down. The main challenge for such a support system is that it needs to interpret individual data automatically and immediately, while the individual is influenced by the same system. My thesis aims at this challenge, focussing on mental workload. In chapter three it is argued that a reliable system probably needs multiple types of measures to infer the user’s internal state, such as driving performance, physiology, and subjective experiences. The main result from chapter four is that users may use support actions of an adaptive system as a warning signal, and thereby not use the system as intended by the designers. In chapter five the potential was explored to use automatic music selection to influence mental workload was, but a direct link between mental effort and music type was not confirmed. Individual data analyses from brainwaves were the topic of chapter six, resulting in highly accurate workload classifications. This inspired the development of a performance and brain-based cruise control described in chapter seven. The adaptive performance of this system led to the conclusion that future research should focus on decreasing the context and time dependency of workload monitors for user adaptive systems

Understandings of Colors: Varieties of Theories in the Color Worlds of the Early Seventeenth Century

In the early seventeenth century, there existed a myriad of theories to account for color phenomena. The status, goal, and content of such accounts differed as well as the range of phenomena they explained. Starting with the journal of Isaac Beeckman (1588–1637), this essay inquires into the features and functions of conceptual reflections upon color experiences. Beeckman played a crucial role in the intellectual development of René Descartes (1596–1650), while at the same time their ideas differed crucially. Early corpuscular conceptions of colors cannot be reduced to the mechanistic variety of Descartes. Moreover, the optical rather than corpuscular features of Descartes’s understanding of colors were essential. A stratification of conceptualizations is proposed that is grounded in various problem contexts rather than philosophical doctrines, thus opening a way to interpret the philosophical parts of color worlds in a more diverse way