Origami, the Japanese art of paper folding, has been used previously to inspire engineering solutions for compact, deployable designs. Action origami, the subset of origami dealing with models designed to move, is a previously unexplored area for engineering design solutions that are deployable and have additional motion in the deployed state. A literature review of origami in engineering is performed, resulting in seven key areas of technical origami literature from a wide variety of disciplines. Spherical mechanisms are identified as the method by which most action origami models achieve complicated motion while remaining flat-foldable. The subset of action origami whose motion originates from spherical mechanisms is termed "kinematic origami''. Action origami is found to contain large coupled systems of spherical mechanisms. All possible action origami models are classified by their spherical mechanism structure, resulting in eight possible categories. Viewing action origami as spherical mechanisms allows the use of established equations for kinematic analysis. Several kinematic origami categories are used to demonstrate a method for the position analysis of coupled systems of spherical mechanisms. Input-output angle relationships and coupler link motions are obtained for a single spherical mechanism, two spherical mechanisms coupled together, and four spherical mechanisms coupled in a loop arrangement. This lays a groundwork from which it is possible to create compact, deployable mechanisms with motion in the deployed state.

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Most tilting pad journal bearing dynamic characteristics estimation methodologies assume perfect shaft tracking by the pads. In other words, they neglect pivot friction. In case of pads having point or line contact that operate under most normal load conditions, the pad tilting is due to a rocking motion which is not greatly influenced by friction. Hence this simplifying assumption might be acceptable. Heavier loading conditions, such as those typically encountered in gearboxes, demand the use of spherical pivots to avoid pivot failure. The spherical pivot is very attractive for this reason, but the tilting motion is rather a sliding action that must occur in the precision ball socket. A valid concern exists for verifying the soundness of assumed shaft tracking by the pads of such bearings. A "fixed test bearing, floating shaft" type of test rig previously built for determining the dynamic characteristics of bearings was accordingly modified to facilitate the testing of shaft tracking for a spherical pivot bearing. This thesis describes the modifications carried out on the rig. The special instrumentation and data acquisition systems implemented to observe the minute pad motion are also discussed. Some preliminary results of the tests are presented for various loading conditions. They show excellent shaft tracking by the pads. More detailed testing and analysis of data is required to fully understand the pad motion and tracking ability of the spherical pivot design. / Master of Science

The growing epidemic of antimicrobial resistance has caused significant morbidity rates worldwide as well as increasing probabilities of cancer recurrence. Efforts to address this epidemic have turned to immunomodulators, a class of molecules which modify the immune system in order to fight off infection. Muramyl dipeptide (MDP) is an immunomodulator of interest due to its specificity for NOD2, a primary receptor involved in immunoregulation. However, use of MDP in vivo causes an overly strong immunostimulatory effect; furthermore, MDP is rapidly cleared from the body due to high solubility and low molecular weight. In order to improve the clinical outlook of MDP, multiple analogues and delivery methods have been explored, with mixed success. MDP analogues have found the most success as adjuvants, although strict FDA approval guidelines limit this approach. Delivery methods for MDP are costly and also induce cytotoxicity, thereby emphasizing the clinical challenges of MDP. Introduced in 1996, Spherical Nucleic Acids (SNAs) are radially oriented oligonucleotides on a nanoparticle surface. SNAs have been shown to readily enter cells with little to no cytotoxicity and in fact, they have found clinical success in a variety of gene delivery and vaccine applications, making them a versatile platform for drug delivery. Herein, we demonstrate that SNAs can be applied as cellular delivery vehicles for MDP. To achieve this, we synthesized dual-layer SNAs whereby two unique oligonucleotides were functionalized onto a gold nanoparticle core. We show that by modulating the surface charge of the SNAs, faster cellular uptake can be achieved, which presents promise for increasing drug delivery and reaching cell compartments of interest. Additionally, we show early evidence that conjugation of MDP to the SNA corona retains MDP activity. Taken together, this work proposes effective SNA designs to deliver muramyl-based immunostimulants, which show promise in the expansion of SNA utility into immunomodulation. / Thesis / Master of Science (MSc) / The growing epidemic of antimicrobial resistance has been linked to deaths, weakened immune systems, and even cancer recurrence. To address this, immunomodulators have become an area of interest. Immunomodulators are capable of modifying the immune system to restore its normal function and fight off infection. Muramyl dipeptide (MDP) is a well-known immunomodulator, however, free MDP is too potent for clinical use. Attempts to modify or deliver MDP have had mixed success. Spherical Nucleic Acids (SNAs) are a 3D orientation of short DNA strands, SNAs are able to readily enter cells with little harmful effects on the cell. Herein, we demonstrate the development of SNAs for MDP delivery. We incorporate two unique DNA strands onto the SNA and leverage charge to enhance cellular uptake. Furthermore, we show early efforts in using the modified SNA as a delivery vehicle for MDP.

La caractérisation et l’étude de l’homogénéisation temps réel d’un mélange de produits liquides ou solides présente une opération clé pour de nombreux domaines industriels.Dans le présent travail, nous proposons un modèle de capteur acoustique sphérique miniaturisé et autonome, adapté à des fonctions de caractérisations en ligne des milieux hétérogènes de différentes natures. Ce capteur a la possibilité d’être dispersé dans un système dynamique en constituant un réseau de capteurs géo-localisables permettant une cartographie des propriétés recherchées du milieu. Sa forme sphérique creuse nous offre la possibilité de loger une électronique programmable pour gérer son fonctionnement par unité ou dans un réseau de capteurs identifiés par codage.D’un point de vu mécanique, le résonateur proposé est assemblé à partir de deux demi-sphères faites d'un matériau approprié (Plexiglas dans le cadre de notre étude), le capteur est mis en résonance à l’aide d’un élément piézo-électrique déposé entre les deux demi-sphères ayant la forme d'un anneau.Après une validation expérimentale du système en adoptant le principe de la trilatération, une étude sur l’atténuation et la vitesse de propagation de l’onde acoustique a été effectuée dans différentes solutions à 35 °C; eau, glucose, huile de colza, lait, gel laitier et grain de caillé en suspension (différente taille). / The characterization and the study of real-time homogenization of a mixture of liquid and solid products present a key operation for many industrial sectors.In this work, we propose a model of spherical acoustic sensor miniaturized and autonomous adapted to different functions of characterization online of heterogeneous media of various kinds. This sensor has the ability to be dispersed in a dynamic system by creating a network of geo-localization for mapping desired properties of the medium. Its spherical hollow shape gives us the opportunity to accommodate a programmable electronic for managing its function as a unit or in a sensor network identified by coding.From a mechanical point of view, the proposed resonator is assembled from two hemi-spheres made of a suitable material (Plexiglas in our study), the sensor is brought into resonance by using an element piezoelectric introduced between the two hemi-spheres having the shape of a ring.After an experimental validation of the system by adopting the principle of trilateration, a mitigation study and propagation velocity of the acoustic wave was performed in different solutions at 35 ° C; water, glucose, rapeseed oil, milk, dairy and grain curd gel suspension (different sizes).

This research is concerned with the self-adaptive numerical solution of the neutral particle radiation transport problem. Radiation transport is an extremely challenging computational problem since the governing equation is seven-dimensional (3 in space, 2 in direction, 1 in energy, and 1 in time) with a high degree of coupling between these variables. If not careful, this relatively large number of independent variables when discretized can potentially lead to sets of linear equations of intractable size. Though parallel computing has allowed the solution of very large problems, available computational resources will always be finite due to the fact that ever more sophisticated multiphysics models are being demanded by industry. There is thus the pressing requirement to optimize the discretizations so as to minimize the effort and maximize the accuracy. One way to achieve this goal is through adaptive phase-space refinement. Unfortunately, the quality of discretization (and its solution) is, in general, not known a priori; accurate error estimates can only be attained via the a posteriori error analysis. In particular, in the context of the finite element method, the a posteriori error analysis provides a rigorous error bound. The main difficulty in applying a well-established a posteriori error analysis and subsequent adaptive refinement in the context of radiation transport is the strong coupling between spatial and angular variables. This research attempts to address this issue within the context of the second-order, even-parity form of the transport equation discretized with the finite-element spherical harmonics method. The objective of this thesis is to develop a posteriori error analysis in a coupled space-angle framework and an efficient adaptive algorithm. Moreover, the mesh refinement strategy which is tuned for minimizing the error in the target engineering output has been developed by employing the dual argument of the problem. This numerical framework has been implemented in the general-purpose neutral particle code EVENT for assessment.

MACHAČ Stanislav: Spherical rollers process innovation by applicaton of cold bulk forming. Diploma thesis of the attendance engineer´s studies, Institute of technology, 2nd year, 2nd level – summer term, study group 5O / 51, school year 2007 / 2008. FSI VUT Brno, department of forming and plastics, May 2008, 75 pages, 6 tables, 4 enclosures. The topic of this thesis is production innovation of spherical rollers for bearings. The innovation is based on the technology of cold bulk forming. According to the literary research and according to the current stage of production is proposed and conceived manufacturing process for cold upsetting instead of turning using in current spherical rollers production. This manufacturing process is dedicated for the bearing type 22226EJ. The production process is conceived with regard to determinate knuckle-joint press LLR 1000 (Smeral Brno, a.s.). Also with regard to determinate half-closed die upsetting and with regard to formability of the steel 100CrMn6. The proposal and check-up of tool functional parts are designed regarding the current setting of particular parts of the press. In the next part of this thesis the proposal of work-room layout dedicated for hand-filling of semi-factured product is conceived. In conclusion the comparison of spherical roller production budget between cold upsetting and turning is conceived.

Diffusion MRI (dMRI) measurements allow us to infer the microstructural properties of white matter and to reconstruct fiber pathways in-vivo. High angular diffusion imaging (HARDI) allows for the creation of more and more complex local models connecting the microstructure to the measured signal. One of the challenges is the derivation of meaningful metrics describing the underlying structure from the local models. The aim hereby is to increase the specificity of the widely used metric fractional anisotropy (FA) by using the additional information contained within the HARDI data. A local model which is connected directly to the underlying microstructure through the model of a single fiber population is spherical deconvolution. It produces a fiber orientation density function (fODF), which can often be interpreted as superposition of multiple peaks, each associated to one relatively coherent fiber population (bundle). Parameterizing these peaks one is able to disentangle and characterize these bundles. In this work, the fODF peaks are approximated by Bingham distributions, capturing first and second order statistics of the fiber orientations, from which metrics for the parametric quantification of fiber bundles are derived. Meaningful relationships between these measures and the underlying microstructural properties are proposed. The focus lies on metrics derived directly from properties of the Bingham distribution, such as peak length, peak direction, peak spread, integral over the peak, as well as a metric derived from the comparison of the largest peaks, which probes the complexity of the underlying microstructure. These metrics are compared to the conventionally used fractional anisotropy (FA) and it is shown how they may help to increase the specificity of the characterization of microstructural properties. Visualization of the micro-structural arrangement is another application of dMRI. This is done by using tractography to propagate the fiber layout, extracted from the local model, in each voxel. In practice most tractography algorithms use little of the additional information gained from HARDI based local models aside from the reconstructed fiber bundle directions. In this work an approach to tractography based on the Bingham parameterization of the fODF is introduced. For each of the fiber populations present in a voxel the diffusion signal and tensor are computed. Then tensor deflection tractography is performed. This allows incorporating the complete bundle information, performing local interpolation as well as using multiple directions per voxel for generating tracts. Another aspect of this work is the investigation of the spherical harmonic representation which is used most commonly for the fODF by means of the parameters derived from the Bingham distribution fit. Here a strong connection between the approximation errors in the spherical representation of the Dirac delta function and the distribution of crossing angles recovered from the fODF was discovered. The final aspect of this work is the application of the metrics derived from the Bingham fit to a number of fetal datasets for quantifying the brain’s development. This is done by introducing the Gini-coefficient as a metric describing the brain’s age.