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Inducing two-way shape memory effect in Nitinol-Polymer Composite
Zeman, Jakub ; Samal, Sneha Manjaree (advisor) ; Mathis, Kristián (referee)
Title: Inducing Two-way Shape Memory Effect in NiTi-polymer Composite Author: Jakub Zeman Supervisor: Sneha Manjaree Samal, Ph.D., Institute of Physics of the Czech Academy of Sciences Abstract: Two-way shape memory effect (TWSME) allows material to ac- tively deform between two remembered shapes without the application of ex- ternal force. The most common stimulus is temperature change with several approaches to induce shape memory effect in the material. The approach stud- ied in this thesis utilizes Nitinol and shape memory polymer. By combining these two materials, bistable TWSME was induced in the composite. Bistable TWSME allows the material to be in both of its remembered shapes at a single temperature. The shape of the material depends on the temperature profile by which the target temperature was reached. To create the composite Nitinol foil was shape set and its surface laser lined to increase adhesion with the polymer. Out of the studied polymers, the best properties for the preparation of com- posite were exhibited by a blend of 60 % TPU and 40 % PCL by weight. The composite was then prepared by hot press and tested. Keywords: inducing two-way shape memory effect, Nitinol, shape memory polymer, composite 1
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Analysis of the marketing communication of the Díky, že můžem project between 2018 and 2022
Zeman, Jakub ; Černá, Eliška (advisor) ; Rosenfeldová, Jana (referee)
This bachelor thesis aims to describe and analyse the marketing communication of the non- profit organisation Díky, že můžem between 2018 and 2022. In its first part, it deals with the theoretical aspects of the topic. It describes the history, activities and values of the association and also offers inside into the characteristics of marketing communication of non-profit and cultural organizations. The second part of the thesis is practical and includes a description of the communication activities of the organisation between 2018 and 2022, from which it then presents an evaluation of the set communication objectives and recommendations for improving communication.
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3D scanning of glossy surfaces
Zeman, Jakub ; Zatočilová, Aneta (referee) ; Koutecký, Tomáš (advisor)
The goal of this bachelor thesis is to experimentally determine the impact of different concentrations of titanium matte coating on the properties of matte film covering glossy surface intended for 3D scanning. Theoretical part of the thesis contains brief introduction to the 3D digitization of real objects as well as more detailed description of the particular scanning method used in this thesis and summary of possible digitizing errors and existing knowledge about matte coatings. The practical part composes of applying the titanium matte coating on specimens using automated coating device thus maintaining the exact same conditions for all concentrations. Following measurement of specimens using 3D scanner and optical profilometer results in determining the optimal concentration of titanium coating providing the best properties of the matte film.
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Experimental Assessment of Influence of Polyethylene Liners' Position on Plastic Deformation in the Run-in Phase of Wear
Zeman, Jakub ; Daniel, Matej (referee) ; Ranuša, Matúš (advisor)
The diploma thesis is focused on the run-in phase of total hip replacement. Mutual adjustment of contact surfaces takes place in this phase and polyethylene acetabular cup shows notable creep behaviour. The magnitude of creep deformations is assessed experimentally in relation to acetabular cups orientation in human body after its implantation. The condition of articulating surfaces is also assessed as well as resulting coefficient of friction in run-in phase. Physiological load and kinematics of the artificial joint as well as physiological conditioning is achieved by new module of existing joint simulator, which is created as part of this thesis. Deformations and condition of articulating surfaces are assessed via optical methods and SEM. Findings about the run-in phase are compared with existing FEM analyses to evaluate simplifications used in these analyses. Measurement of creep deformations has also potential to improve the accuracy of acetabular wear diagnosis in clinical practice.
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Novel hepatitis C virus proteins
Zeman, Jakub ; Vopálenský, Václav (advisor) ; Horníková, Lenka (referee)
The hepatitis C virus (HCV) is a major etiological agent of chronic liver diseases. More than 170 million people worldwide are chronically infected, and more than 100 thousand of them develop hepatocellular carcinoma a year. HCV is an enveloped, positive-sense single-stranded RNA virus (+ssRNA virus) of the family Flaviviridae. Its genome is translated to produce a single polyprotein precursor that is further processed by cellular and viral proteases to form 10 viral proteins. Moreover, there is another protein encoded in an alternative reading frame. Two alternative translation mechanisms have been proposed for expression of this alternative reading frame protein (ARFP): a frameshift mechanism and translation initiating from internal start codons. Despite ten years of research its role in vivo is not yet explained. It appears that secondary structures in the core encoding region of HCV genome but not ARFP expression are required for robust viral translation and replication. The results of recent studies suggest that mutations distorting these structures may result not only in slowing down the viral cycle but also in a brand new and utterly unusual serological profile in patients as well as an increased level of expression of ARFP.
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Binding of eIF3 in complex with eIF5 and eIF1 to the 40S ribosomal subunit is accompanied by dramatic structural changes
Zeman, Jakub
In eukaryotic translation, eukaryotic initiation factors (eIFs) are at least as important as the ribosome itself. Some of these factors play different roles throughout the entire process to ensure proper assembly of the preinitiation complex on mRNA, accurate selection of the initiation codon, errorless production of the encoded polypeptide and its proper termination. Perhaps, the most important factor integrating signals from others and coordinating their functions on the ribosome is eIF3. In Saccharomyces cerevisiae, eIF3 is formed by five subunits. All these subunits contain structural motifs responsible for contact with ribosomal proteins and RNAs. In addition to these highly structured parts, the rest of eIF3 is unstructured and very flexible. Therefore, despite the recent progress thanks to the use of a cryo-electron microscopy, a precise structure and position of eIF3 on the 40S ribosomal subunit are still not known. Also, the presence of eIF3 on 80S during early elongation and its role in reinitiation and readthrough are not fully understood. In order to crack mysteries of yeast eIF3, we used x-ray crystallography, chemical cross- linking coupled to mass spectrometry, and various biochemical and genetic assays. We demonstrated that eIF3 is very compactly packed when free in solution. This...
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Binding of eIF3 in complex with eIF5 and eIF1 to the 40S ribosomal subunit is accompanied by dramatic structural changes
Zeman, Jakub
In eukaryotic translation, eukaryotic initiation factors (eIFs) are at least as important as the ribosome itself. Some of these factors play different roles throughout the entire process to ensure proper assembly of the preinitiation complex on mRNA, accurate selection of the initiation codon, errorless production of the encoded polypeptide and its proper termination. Perhaps, the most important factor integrating signals from others and coordinating their functions on the ribosome is eIF3. In Saccharomyces cerevisiae, eIF3 is formed by five subunits. All these subunits contain structural motifs responsible for contact with ribosomal proteins and RNAs. In addition to these highly structured parts, the rest of eIF3 is unstructured and very flexible. Therefore, despite the recent progress thanks to the use of a cryo-electron microscopy, a precise structure and position of eIF3 on the 40S ribosomal subunit are still not known. Also, the presence of eIF3 on 80S during early elongation and its role in reinitiation and readthrough are not fully understood. In order to crack mysteries of yeast eIF3, we used x-ray crystallography, chemical cross- linking coupled to mass spectrometry, and various biochemical and genetic assays. We demonstrated that eIF3 is very compactly packed when free in solution. This...
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Binding of eIF3 in complex with eIF5 and eIF1 to the 40S ribosomal subunit is accompanied by dramatic structural changes
Zeman, Jakub ; Valášek, Leoš (advisor) ; Štefl, Richard (referee) ; Man, Petr (referee)
In eukaryotic translation, eukaryotic initiation factors (eIFs) are at least as important as the ribosome itself. Some of these factors play different roles throughout the entire process to ensure proper assembly of the preinitiation complex on mRNA, accurate selection of the initiation codon, errorless production of the encoded polypeptide and its proper termination. Perhaps, the most important factor integrating signals from others and coordinating their functions on the ribosome is eIF3. In Saccharomyces cerevisiae, eIF3 is formed by five subunits. All these subunits contain structural motifs responsible for contact with ribosomal proteins and RNAs. In addition to these highly structured parts, the rest of eIF3 is unstructured and very flexible. Therefore, despite the recent progress thanks to the use of a cryo-electron microscopy, a precise structure and position of eIF3 on the 40S ribosomal subunit are still not known. Also, the presence of eIF3 on 80S during early elongation and its role in reinitiation and readthrough are not fully understood. In order to crack mysteries of yeast eIF3, we used x-ray crystallography, chemical cross- linking coupled to mass spectrometry, and various biochemical and genetic assays. We demonstrated that eIF3 is very compactly packed when free in solution. This...
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