3,371 research outputs found
Optimizing care for ischemic stroke and tia patients
No full textWeinstein, H. [Promotor]Berg-Vos, R.M. van den [Copromotor]Bosboom, W.M.J. [Copromotor
Physical activity & exercise in vascular disease: Moving against cognitive decline and vascular events?
No full textWeinstein, H. [Promotor]Kappelle, L.J. [Promotor]Berg - Vos, R.M. van den [Copromotor]Geerlings, M.I. [Copromotor
R.M. Simmons presentation, Rena Smart book review
No full textR.M. Simmons of the Gospel Music Workshop of America gives a presentation on the African influence in the African American religious experience. He explains how African slaves brought to America their concept of music (utilitarian concept of music). Simmons further discusses the fusion between the utilitarian concept and the Western concept of religion resulting in spirituals. He also describes hymn categories in early forms of formal African American worship experiences. Simmons takes questions from the audience among which is Dr. Riggins Earl Jr. Video concludes with a book review on Christian Theology and Ethics by Rena Smart.The Atlanta University Center Robert W. Woodruff Library acknowledges the generous support of the National Endowment for Humanities - Humanities Collections and Reference Resources Implementation Project Grant in supporting the processing and digitization of a number of its major archival collections as part of the project: Spreading the Word: Expanding Access to African American Religious Archival Collections at the Atlanta University Center Robert W. Woodruff Library.</em
Velocity-Gradient Probability Distribution Functions in a Lagrangian Model of Turbulence
No full textThe Recent Fluid Deformation Closure (RFDC) model of lagrangian turbulence is recast in path-integral language within the framework of the Martin-Siggia-Rose functional formalism. In order to derive analytical expressions for the velocity-gradient probability distribution functions (vgPDFs), we carry out noise renormalization in the low-frequency regime and find approximate extrema for the Martin-Siggia-Rose effective action. We verify, with the help of Monte Carlo simulations, that the vgPDFs so obtained yield a close description of the single-point statistical features implied by the original RFDC stochastic differential equations
Buckled precompressed elements: A new class of control actuators for subscale UAVs
No full textThis thesis presents the use of a new class of flight control actuators employing Post-Buckled Precompressed (PBP) piezoelectric elements in morphing wing Uninhabited Aerial Vehicles (UAVs). The new actuator relies on axial compression to amplify deflections and control forces simultaneously. Two designs employing morphing wing panels based on PBP actuators were conceived. One design relied on a change in curvature of the actuators to control the camber of the airfoil. Axial compression of the actuators was ensured by means of rubber bands and increased end rotation levels with almost a factor of two up to +/- 13.6deg peak-to-peak, with excellent correlation between theory and experiment. Wind tunnel tests quantitatively proved that wing morphing induced roll acceleration levels in excess of 1500deg/sˆ2. A second design employed PBP actuators in a wing panel with significant thickness, relying on a highly compliant Latex skin to allow for shape deformation and at the same time induce an axial force on the actuators. Bench tests showed that due to the axial compression provided by the skin end rotations were increased with more than a factor of two up to +/- 15.8deg peak-to-peak up to a break frequency of 34Hz. Compared to conventional electromechanical servoactuaters, the PBP actuators showed a net reduction in flight control system weight, slop and power consumption for minimal part count. Both morphing wing concepts showed that PBP piezoelectric actuators have significant benefits over conventional actuators and can be successfully applied to induce aircraft control.Aerospace Engineerin
Anti-predator behaviour of Cape fur seals Arctocephalus pusillus pusillus in relation to predation by white sharks Carcharodon carcharias around Seal Island, False Bay, South Africa
No full textIncludes bibliographical references (leaves 161-202).How predators affect the behaviour of their prey is one of the most studied subjects in behavioural ecology, with many hypothesis and models explaining how animals should behave and even more descriptive studies detailing how they do. The unification of the empirical with the theoretical, however, remains limited. The overall aim of my thesis was to address this paucity at Seal Island, South Africa, where recently quantified patterns of predation pressure by white sharks Carcharodon carcharias on Cape fur seals Arctocephalus pusillus pusillus suggested a landscape of fear particularly apposite to this
Calcium Bioavailability and Exchangeability in Milk: An in vitro study to investigate the influence of calcium salt fortification using 45Ca
No full textCalcium is an important nutrient for both young and elderly people which can, among others, stimulate healthy bone growth and prevent osteoporosis. Therefore, nutrition with sufficient calcium is of great importance. The highest calcium nutrient density for all foods can be found in bovine milk, which contains on average 1.2 g Ca / L. To increase the amount of bioavailable calcium, milk can be fortified by the addition of different calcium salts. In this research the bioavailability and exchangeability of calcium in unfortified and fortified skimmed milk was studied by in vitro methods using equilibrium dialysis and ultracentrifugation to separate different fractions in milk. Radioactive 45Ca was used to follow the exchange behaviour of calcium between the three different fractions in milk: casein micelles, serum proteins, and soluble calcium. For unfortified milk it was found that 34.9 ± 2.2% of the calcium was present in the soluble phase, 9.1 ± 0.6% was bound to serum proteins, and 56 ± 1.6% was present in the casein micelles, which confirmed the results in literature. In addition, with the investigation of the exchange behaviour of 45Ca, it was confirmed that ~40% of calcium in casein micelles is hardly exchanged.To investigate the influence of calcium fortification on the calcium equilibrium in milk, six different calcium salts were selected to be synthesized: calcium chloride, calcium carbonate, calciumgluconate, tri-calcium di-citrate, calcium lactate, and tri-calcium phosphate. Of these, calcium chloride, calcium carbonate, calcium gluconate, and tri-calcium di-citrate were successfully synthesized. Further experiments were performed with calcium chloride and calcium carbonate, intrinsically labelled with 45Ca. From fractionation with ultracentrifugation, it was concluded that addition of calcium chloride led to an increase of calcium in the soluble phase, which might indicate an increase in bioavailability. Fortification of milk with 45Ca labelled calciumcarbonate did not lead to an exchange of 45Ca with the calcium present in milk, indicating that calcium carbonate is unlikely to make calcium in milk more bioavailable. In conclusion, a better understanding of the solubility and exchangeability of Ca in milk and the influence of milk fortification with calcium chloride and calcium carbonate is obtained by using 45Ca as a tracer.Chemical Engineerin
Author Correction: Global geochemical fingerprinting of plume intensity suggests coupling with the supercontinent cycle
No full textThe original version of this Article omitted from the author list the 4th and 5th authors, Grant Cox and Ross Mitchell, who were both at Curtin University. Consequently, the corrected version of the Acknowledgements removes the following from the original version: ‘and Ross Mitchell’. In addition, the following was added to the Author Contributions: ‘G.M.C. and R.M. were involved in an early attempt of this study.’. This has been corrected in both the PDF and HTML versions of the Article
Android Tor Tribler Tunneling (AT3): TI3800 Bachelorproject
No full textTribler is a decentralized peer-to-peer file sharing system. Recently the Tribler development team has introduced anonymous internet communication using a Tor-like protocol in their trial version. The goal of our bachelor project is to port this technology to Android devices. This is a challenging task because cross-compiling the necessary libraries to the ARM CPU architecture is uncharted territory. We have successfully ported all dependencies of Tribler to Android. An application called Android Tor Tribler Tunneling (AT3) has been developed that tests whether these libraries work. This application downloads a test torrent and measures information such as CPU usage and download speed. Based on this information we have concluded that it is currently not viable to run the anonymous tunnels on an Android smartphone. Creating circuits with several hops that use encryption is very computationally expensive and modern smartphones can hardly keep up. By using optimized cryptographic libraries such as gmp or with the recently announced ARMv8 architecture which supports hardware-accelerated AES encryption, creating such circuits might become possible.Tribler developmentParallel and Distributed Systems groupElectrical Engineering, Mathematics and Computer Scienc
Colonising "The Coral Island": A Postcolonial Reading of R.M. Ballantyne's Children's "Classic"
No full textstudent essayBeing written during the rise of the British Empire in the 1850sm R.M. Ballantyne's boys' adventure story "The Coral Island" is in many ways a product of its time, conveying imperial ideas and Victorian values to the young reader. Through his portrayal of the native inhabitants in relation to his descriptions of the three British protagonists, the author creates a stereotyped image of the natives as primitive savages. Due to the further use of a first person narrator and realist pretensions, the dated racist ideas become influential upon the reader. In spite of the fact that the novel has been considered as an entertaining children's classic by generations since its first publication, "The Coral Island" should not be classified as good children's literature today but should rather be historicised as a result of its controversial contents. By adopting a postcolonial approach and applying postcolonial theory in my analysis of R.M. Ballantyne's "The Coral Island", I have in this essay endeavoured to demonstrate in what ways the novel would prove problematic as a children's book today. In my first chapter I present the imperial ideas and Victorian values that are conveyed, whereas in my second chapter I discuss Ballantyne's stereotyping of the natives. As a result of my study of this novel, I have exemplified how the author portrays the three British boys as representative of the Victorian ideals of the time. I have also illustrated their assumed superiority over nature and their roles as colonisers. Furthermore, my analysis of "The Coral Island" has revealed how Ballantyne communicates both white superiority as well as the Western "oblibation" to civilise primitive people throug Christian conversion. Consequently, the novel promotes the ideology of its time. As a result of my findings, I would like to argue that "The Coral Island" should today be viewed as a text conveying historical ideas and values rather than as an exciting children's classic
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