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Equilibrium description of Maltose Binding Protein
De 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.
Power grid complex network evolutions for the smart grid
The shift towards an energy grid dominated by prosumers (consumers and producers of energy) will inevitably have repercussions on the electricity distribution infrastructure. Today the grid is a hierarchical one delivering energy from large scale facilities to end-users. Tomorrow it will be a capillary infrastructure at the medium and low voltage levels that will support local energy trading among prosumers. We investigate how different network topologies and growth models facilitate a more efficient and reliable network, and how they can facilitate the emergence of a decentralized electricity market. We show how connectivity plays an important role in improving the properties of reliability and path-cost reduction. Our results indicate that a specific type of evolution balances best the ratio between increased connectivity and costs to achieve the network growth.
Collectieve en distributieve interpretaties van numerieke uitdrukkingen en kwantoren bij kinderen van 5 en 6
Zinnen die numerieke uitdrukkingen bevatten kunnen aanleiding geven tot twee verschillende interpretaties: een collectieve en een distributieve. In het huidige onderzoek is gebruik gemaakt van twee verschillende soorten zinnen (mét en zonder distributieve kwantor) en drie verschillende soorten contexten: een distributieve, een collectieve en een gemengd distributieve/collectieve context. Kinderen in de leeftijd van 4 tot 6 jaar werd gevraagd om de zinnen te beoordelen in combinatie met de contexten. Hieruit kwam naar voren dat kinderen in de neutrale zinsconditie toegang hadden tot zowel de collectieve als de distributieve context en dat de toevoeging van de kwantor alleen van invloed was op het acceptatiepercentage wanneer er sprake was van een (tegenstrijdige) collectieve context. Echter werd deze combinatie door een klein percentage van de kinderen wel geaccepteerd. Dit wijst erop dat een deel van de kinderen in deze leeftijdscategorie zich bewust is van de restricties die gelden voor het gebruik van kwantoren, maar tegelijkertijd een minderheid van zich hier nog niet bewust van is of deze regels minder strict interpreteert.
The potential of stable isotope analysis: Transhumance at Francavilla Marittima, Calabria, Italy
Control of Surface Wettability Using Tripodal Light-Activated Molecular Motors
Monolayers of fluorinated light-driven molecular motors were synthesized and immobilized on gold films in an altitudinal orientation via tripodal stators. In this design the functionalized molecular motors are not interfering and preserve their rotary function on gold. The wettability of the self-assembled monolayers can be modulated by UV irradiation.
Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific
The 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.