This thesis deals with controlling a color graphic LED display using an FPGA. The first half of the theoretical part of this paper describes the properties of the used FPGA, the data source and a principle of controlling an RGB LED display. The second half describes an implementation of pulse width modulation and binary code modulation which enables the control of brightness of the display and of color depth of every sub-pixel. The practical part on the other hand describes the designing and the implementation of this module in the VHDL language. Then it explains the transfer of image data from Blackfin processor to the memory via PPI interface, the subsequent process of reading data from the memory, conversion of the data to a serial format and finally it describes the process of sending the data to the LED controller. The module was realized on the Digilent Atlys development board equipped with the Spartan-6 FPGA and was tested on a 32x20 light panel for the firm Ing. Ivo Herman, CSc.

Leishmania is a protozoan parasite of vertebrates transmitted by the bite of infected phlebotomine sandflies. In humans, it causes a disease called leishmaniasis, which ranks as one of the most serious neglected tropical diseases. In the vectorial part of the life cycle, the crucial moment is when the flagellate forms (promastigotes) attach to the midgut epithelium of the sandfly. For most leishmania species, little is known about which types of phlebotomine receptors and leishmania surface antigens participate in the binding. Phage display was used to screen for Leishmania mexicana peptide ligands which may play a role in such binding. By affinity selection of phages incubated with promastigote cells, 16 unique peptides were identified. Fluorescent labelling of peptide-bearing phages indicated their putative binding sites on the leishmania surface. Based on the hypothesis that the identified peptides may be a part of receptors found in the phlebotomine midgut, experiments were performed where the sandflies were infected with promastigotes whose binding sites were blocked by two different peptide-bearing phages. The extent of the infection was different between the two cases. However, no statistically significant difference from the control group was observed. Despite unsuccessful attempts to identify a...

In affinity protein biotechnology the selective bindingbetween a chosen protein and an interacting biomolecule isutilized for a variety of applications including bioseparation,detection and therapy. Traditionally, affinity proteinsrecruited for such applications have been derived from naturalproteins or immunoglobulins generated via immunization routes.More recently, advances in the construction and handling oflarge collections of proteins(denoted libraries) generated invitro have opened up for new routes for the development ofaffinity proteins with desired properties. In this study, phage display selection technology was usedfor the isolation of novel human CD28 (hCD28)-specific affinityproteins from a protein library constructed by combinatorialprotein engineering of a 58 aa protein domain (Z) derived fromstaphylococcal protein A (SPA). From selections using hCD28 asa target molecule, several hCD28-specific affinity proteins(denoted affibodies) could be identified and analysis of theisolated affibody variants revealed a high degree of sequencehomology between the different clones. The biosensor analysisshowed that all variants bound to hCD28 with micromolardissociation constants (KD) and no significant cross-reactivitytowards the structurally related T-cell receptor hCTLA-4 couldbe observed. The apparent binding affinity for hCD28 of one ofthe isolated affibodies was further improved through fusion toa human Fc fragment fusion partner, resulting in a homodimericversion of the affibody ligand showing avidity effects uponhCD28 binding. Further, a co-culture experiment involvingJurkat T-cells and CHO cell lines tranfected to express eitherhuman CD80 or LFA-3 on the cell surface showed that apreincubation of Jurkat cells with one of the affibody variantsresulted in a specific concentration-dependent inhibition ofthe CD80 induced IL-2 production. This indicates that thisaffibody binds to hCD28 and specifically interferes with theco-stimulation signal mediated via hCD28 and hCD80. ACD28-specific binding protein could have potential as an agentfor various immunotherapy applications. In a second study, anaffinity protein-based strategy was investigated forsite-specific anchoring of proteins onto cellulose for woodfiber engineering purposes. Here, affinity proteins derivedfrom different sources were used for the assembly of acellulosome-like complex for specific and reversible anchoringof affinity domain-tagged reporter proteins to acellulose-anchored fusion protein. A fusion protein between acellulose binding module (Cel6A CBM1) derived from the fungalTrichoderma reesei and a five-domain staphylococcal protein A(SPA) moiety was constructed to serve as a platform for thedocking of reporter proteins produced as fusion to two copiesof a SPA-binding affibody affinity protein (denoted ZSPA-1),selected by phage display technology from a Z domain basedprotein library. In a series of experiments, involving repeatedwashing and low pH elutions, affinity tagged Enhanced GreenFluorescent Protein (EGFP) and Fusarium solani pisi lipasecutinase reporter proteins were both found to be specificallydirected from solution to a region of a cellulose-based filterpaper where the SPA-CBM fusion protein previously had beenpositioned. This showed that the cellulose-anchored SPA-Cel6ACBM1 fusion protein had been stably anchored to the surfacewith retained binding activity and that the interaction betweenSPA and the ZSPA-1 affibody domain was selective. phage display, combinatorial, selection, CD28, cellulosome,cellulose, affibody / NR 20140805

This dissertation examines the developments and progress of spatial calibration procedures for Optical See-Through (OST) Head-Mounted Display (HMD) devices for visual Augmented Reality (AR) applications. Rapid developments in commercial AR systems have created an explosion of OST device options for not only research and industrial purposes, but also the consumer market as well. This expansion in hardware availability is equally matched by a need for intuitive standardized calibration procedures that are not only easily completed by novice users, but which are also readily applicable across the largest range of hardware options. This demand for robust uniform calibration schemes is the driving motive behind the original contributions offered within this work. A review of prior surveys and canonical description for AR and OST display developments is provided before narrowing the contextual scope to the research questions evolving within the calibration domain. Both established and state of the art calibration techniques and their general implementations are explored, along with prior user study assessments and the prevailing evaluation metrics and practices employed within. The original contributions begin with a user study evaluation comparing and contrasting the accuracy and precision of an established manual calibration method against a state of the art semi-automatic technique. This is the first formal evaluation of any non-manual approach and provides insight into the current usability limitations of present techniques and the complexities of next generation methods yet to be solved. The second study investigates the viability of a user-centric approach to OST HMD calibration through novel adaptation of manual calibration to consumer level hardware. Additional contributions describe the development of a complete demonstration application incorporating user-centric methods, a novel strategy for visualizing both calibration results and registration error from the user’s perspective, as well as a robust intuitive presentation style for binocular manual calibration. The final study provides further investigation into the accuracy differences observed between user-centric and environment-centric methodologies. The dissertation concludes with a summarization of the contribution outcomes and their impact on existing AR systems and research endeavors, as well as a short look ahead into future extensions and paths that continued calibration research should explore.

No description available.

Thesis advisor: Jianmin Gao / Lipid reporters are key signaling molecules in a number of biological processes ranging from apoptosis in mammalian cells to novel resistance mechanisms in pathogenic bacteria. Developing probes to target these lipids is a worthy endeavor, especially when better reporters could mean lives saved. This is particularly true considering new antibiotic resistant pathogens emerge every year with evolving lipid compositions. To combat these pathogens and prevent a potential global pandemic, it is imperative to continue the development of novel and innovative probes/drugs to meet this daunting challenge. To fulfill this demand, we must continue to establish new strategies, enhance current technologies and advance scientific understanding. Only by pushing the boundaries of what is currently possible will we remain one step ahead of these diseases. Diseases like mcr-1 positive bacteria, first documented in 2016, remain largely uncontested. Herein, we seek to expand the available probes specific to key lipid reporters for phosphatidylserine, lysyl-phosphatidylglycerol, and phosphoethanolamine lipid A. Cyclic phage libraries were first utilized to target phosphatidylserine, ultimately producing weak binders. Refining our phage display libraries to include reversible covalent warheads allowed for the identification of more potent lipid reporters. In doing so, we have created the tools necessary to interrogate the unique resistance mechanisms expressed by these drug-resistant pathogens. A strong correlation was observed between peptides binding mcr-1 positive strains, LPS modification on the surface of these bacteria, and level of colistin resistance. To our knowledge, these peptides are the only probes capable of demonstrating this correlation. We surmise that the methods discussed here will pave the way for better diagnostic tools for these resistant pathogens. A recurring method of resistance among gram-positive and gram-negative bacteria has been to decorate their surface with positive amines to repel cationic antimicrobial peptides. As such, our current APBA library and the libraries in development in the Gao lab would be ideally suited to target these and other undiscovered resistance mechanisms. / Thesis (PhD) — Boston College, 2020. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

The objective of this study was to identify peptide ligands, using phage display techniques, which bind sites on mouse embryos, ovaries, cytoplasmic membranes and/or intracytoplasmic components. Specifically, M13 coliphage 7-mer, 12-mer and 15-mer random peptide libraries were used separately for biopanning. Peptides derived from the amplified pools were sequenced and studied. The phage display for in vivo ovary experiments yielded no pool of peptides after two cycles of biopanning and re-amplification. With the same initial concentration of a random 7-mer or 12-mer library, there were repeating sequences derived after three and four biopanning cycles on mouse embryos and unfertilized ova. The sequences were not distinguishable from a control group. Subsequent experimentation using a random 15-mer library to select for internalized phage-peptides yielded two apparent consensus sequences, RNVPPIFNDVYWIAF (9/32 or 28%) and HGRFILPWWYAFSPS (11/32 or 34%). The 15-mer control group yielded no clones. The deduced peptide sequences were compared to known sequences to ascertain their uniqueness. No significant similarities were found, yielding two possible novel motifs. Through this adapted process of phage display and further research, the phage display technology may be used as a tool in the recognition of specific mouse gamete sites. By identifying binding sites of mouse gametes, the peptides might be exploited as a means of studying the embryo cell surface or cytoplasmic components and mouse sperm-egg interactions. Such peptides may also be used for macromolecule delivery in transfection or transgenesis. / Master of Science

No description available.

No description available.

No description available.