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Solid state long chain branching of polypropylene in supercritical CO2
No full textDe begeleider en/of auteur heeft geen toestemming gegeven tot het openbaar maken van de scriptie.
The supervisor and/or the author did not authorize public publication of the thesis.
The Solid* toolset for software visual analytics of program structure and metrics comprehension: From research prototype to product
No full textSoftware visual analytics (SVA) tools combine static program analysis and fact extraction with information visualization to support program comprehension. However, building efficient and effective SVA tools is highly challenging, as it involves extensive software development in program analysis, graphics, information visualization, and interaction. We present a SVA toolset for software maintenance, and detail two of its components which target software structure, metrics and code duplication. We illustrate the toolset’s usage for constructing software visualizations with examples in education, research, and industrial contexts. We discuss the design evolution from research prototypes to integrated, scalable, and easy-to-use products, and present several guidelines for the development of efficient and effective SVA solutions.
Deposition of SiO2 nanoparticles in heat exchanger during combustion of biogas
No full textExperimental results are presented on silica deposition in a typical domestic heat exchanger during combustion of siloxane-containing gas as a model of biogas that is produced naturally during the anaerobic degradation of organic material in landfills and waste water treatment plants. A model of silica deposition is developed. The main objective is to demonstrate that the mass flux of silica to heat exchanger surfaces is not sensitive to details of particle coagulation process and particle size distribution. It is shown that the deposition flux of silica depends linearly on siloxane concentration in input air/gas mixture.
Improving Staging Accuracy in Melanoma
No full textDe incidentie van het melanoom stijgt wereldwijd. Door de onvoorspelbare en onregelmatige disseminatie van het melanoom is de behandeling uitdagend. Hedendaags is het nog steeds vrijwel onmogelijk om een patiënt met een op afstand gemetastaseerd melanoom te genezen. Nieuwe therapieën, zoals immunotherapie en doelgerichte therapieën geven echter hoop voor de toekomst. Om therapeutische beslissingen te maken is een accurate stadiëring van het melanoom nodig, dit begint vaak met de histopathologie van het primaire melanoom. Dit proefschrift heeft laten zien dat de histopathologische diagnose van het melanoom subjectief en complex is. Bovendien is een revisie van een gespecialiseerde patholoog nodig voordat een definitieve behandeling kan worden voorgesteld en uitgevoerd. De essentiële histopathologische karakteristieken zijn Breslow dikte, ulceratie en tumor mitose index, dit proefschrift heeft laten zien dat deze pathologische karakteristieken
uitstekend reproduceerbaar door pathologen. Een andere pathologische karakteristiek van het
melanoom is microsatellitose, dit proefschrift heeft laten zien dat de prognose van melanoom
patiënten sterk verslechtert als dit karakteristiek aanwezig is.
Voor de detectie van metastasen van het melanoom speelt nucleaire beeldvorming een belangrijke rol. Dit proefschrift heeft laten zien dat een FDG-PET/CT essentieel is bij melanoom patiënten met palpabele lymfogene metastasen, omdat dit de stadiëring van deze patiënten verbetert.
Door de verbetering van de stadiëring van het melanoom wordt het steeds duidelijker hoe het melanoom zich biologisch gedraagt en krijgen patiënten een nauwkeurige prognose. Bovendien kunnen medische multidisciplinaire teams melanoom patiënten beter behandelen met een geïndividualiseerde behandeling.
The incidence of melanoma is rising worldwide. Due to the unpredictability and erratic dissemina-tion of melanomas, its management is challenging. It is currently almost impossible to cure distant disseminated melanoma patients, although new therapies, including immunotherapy and drug targeted therapies, offer hope for the future. Accurate staging is extremely important for clinical decision making and often starts with the histopathology of the primary melanoma. The present thesis showed that the histopathologic diagnosis of melanoma is subjective and complex. Furthermore this thesis showed that revision by a specialist melanoma pathologist is required before definitive diagnosis and treatment. The essential pathologic features are Breslow thickness, ulceration, and tumor mitotic rate, this thesis showed that these pathologic features have a high interobserver agreement between pathologists. Another melanoma pathologic feature is microsatellites, this thesis showed that prognosis of melanoma patients is poor when microsatellites are present.
For the detection of melanoma metastases nuclear imaging plays an important role. This thesis showed that FDG-PET/CT is essential in melanoma patients with clinically detectable lymph node metastases, as this improves the staging of these patients.
Through the improvement of staging accuracy and therefore the improved understanding of the biological behavior, melanomas are becoming more predictable. Due to the accurate staging patients will be informed about their prognosis more accurately and medical multidisciplinary teams will be able to treat melanoma patients with more suitable, patient-tailored, therapies.
Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific
No full textThe annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop flights of a week’s duration or longer. At a minimum, their decisions will affect wind profitability and thus reduce energetic costs of migration; in the extreme, poor decisions or unpredictable weather events will risk survival. We used satellite telemetry to track the annual migration of 24 bar-tailed godwits and analysed their flight performance relative to wind conditions during three major migration legs between nonbreeding grounds in New Zealand and breeding grounds in Alaska. Because flight altitudes of birds en route were unknown, we modelled flight efficiency at six geopotential heights across each migratory segment. Birds selected departure dates when atmospheric conditions conferred the greatest wind assistance both at departure and throughout their flights. This behaviour suggests that there exists a cognitive mechanism, heretofore unknown among migratory birds, that allows godwits to assess changes in weather conditions that are linked (i.e. teleconnected) across widely separated atmospheric regions. Godwits also showed adaptive flexibility in their response not only to cues related to seasonal changes in macrometeorology, such as spatial shifting of storm tracks and temporal periods of cyclogenesis, but also to cues associated with stochastic events, especially at departure sites. Godwits showed limits to their response behaviours, however, especially relative to rapidly developing stochastic events while en route. We found that flight efficiency depended significantly upon altitude and hypothesize that godwits exhibit further adaptive flexibility by varying flight altitude en route to optimize flight efficiency.
A sharp threshold for an anisotropic bootstrap percolation model
No full textIn bootstrap percolation on the two-dimensional lattice the initial state of any site is infected with probability p and healthy with prob- ability 1 − p. A healthy site can become infected if its neighbors are and an infected site remains infected for all time. The process goes on until all sites are infected or there is a point where no more sites can become infected. If all the sites become infected we say the initial configuration percolates. Balogh and Bollobs [BB03] were able to give a sharp threshold for the standard bootstrap percolation model in a way that can be used for other models.
In this bachelor thesis a sharp threshold is given for the anisotropic bootstrap percolation model. The standard and the anisotropic model are compared and it is shown that the fundamental theorem of Friedgut and Kalai [FK96] can be used to give the sharp threshold in both cases. It is shown that the behaviour on the grid and the torus is almost the same. Using a slightly adjusted version of the lemma of Aizenman and Lebowitz [AL88], the length of the epsilon-window for anisotropic bootstrap percolation is determined.
Research Report 1: The Role of The Lateral Gate Of SecYEG
No full textDe begeleider en/of auteur heeft geen toestemming gegeven tot het openbaar maken van de scriptie.
The supervisor and/or the author did not authorize public publication of the thesis.
Artificial metalloenzymes for enantioselective catalysis
No full textArtificial metalloenzymes have emerged over the last decades as an attractive approach towards combining homogeneous catalysis and biocatalysis. A wide variety of catalytic transformations have been established by artificial metalloenzymes, thus establishing proof of concept. The field is now slowly transforming to take on new challenges. These include novel designs, novel catalytic reactions, some of which have no equivalent in both homogenous catalysis and biocatalysis and the incorporation of artificial metalloenzymes in chemoenzymatic cascades. Some of these developments represent promising steps towards integrating artificial metalloenzymes in biological systems. This review will focus on advances in this field and perspectives discussed.
Naipauls India
No full textV.S. Naipaul oordeelt hard over de landen die hij bezoekt en met name India moet het ontgelden. Het land waar zijn grootouders zijn geboren is, als Naipaul het in de jaren zestig voor het eerst bezoekt, net onafhankelijk en op zoek naar een eigen identiteit. In zijn India-trilogie beschrijft Naipaul de volwassenwording van India.
Deze scriptie onderzoekt de manier waarop Naipaul zijn ervaringen in en opvattingen over India een literair journalistieke vorm geeft. Hiervoor gebruik ik handvaten die de retorische ethiek van onder andere James Phelan biedt.
Ten tweede onderzoek ik de impact van de vorm die Naipaul kiest in het maatschappelijke debat rondom India. Wat zegt Naipaul als je zijn werk beziet in een bredere context en welke rol spelen de specifieke literaire vormen die hij gebruikt hierin? Deze vraag onderzoek ik met behulp van het new historicism zoals wetenschappers als Stephen Greenblatt, Louis Montrose en Jane Tompkins propageren.
Zijn beeld van de werkelijkheid vraagt van de lezer niet alleen een rationeel begrip van de situatie en geschiedenis van India maar ook een dieper, emotionele betrokkenheid bij het onderwerp. Een duidelijke reactie op de starre journalistieke of wetenschappelijke vorm.