The buckling of stiff film on a substrate had been of great interest as this response happen spontaneously and is self-organizing. This provides an unconventional, scalable and easy way to fabrication surfaces with tunable structures from the range of nanometers to micrometers. We optimized a process to fabricate stretchable electrodes by transferring wrinkled gold onto elastomer. We tested their electrochemical sensing functionality through detection of glucose concentration with or without strain. Results showed that the stretchable electrodes provide high sensitivity for the detection of glucose (860 ± 60 µA/mM.cm2), comparable to electrodes before transfer. The current detected was also consistent under strain. Investigation of the resistance indicates that the electrode configuration under strain is important as current running parallel to direction of strain is much more affected under tension. We also developed a fast and facile process to fabricate surfaces that consisted of wrinkles and nanoparticles. Using such surfaces, we tested the omniphobicity effect of hierarchical structures consisting of wrinkles and nanoparticles. Results show that all the fluorinated structured surfaces were hydrophobic, ranging from water contact angle of 125° for wrinkled surfaces to 155° for hierarchical surfaces. The surfaces that were either wrinkled or decorated with nanoparticles were oleophilic with low hexadecane contact angles (~26° and ~55° respectively). The combination of both structures achieved oleophobicity of more than 110°. The effectiveness of nanoparticles for low surface tension liquid were due to its re-entrant like structure. The omniphobic surfaces were also shown to be repellent to blood (>135°), making it a potential material for use medical devices. / Thesis / Master of Applied Science (MASc) / Wrinkling is a phenomenon often seen in real life, such as on the skin of a dried plum or human. It is possible to fabricate such wrinkles through having a stiff thin film adhered to an elastic foundation and compressing the foundation. The wrinkles are useful for fabrication of stretchable electrodes as their structure allows the film to stretch without breaking through unfolding. Here, we fabricated stretchable electrodes by transferring such wrinkled structures onto elastic foundation. These stretchable electrodes are shown to be able to detect the concentration of glucose in solution even when stretched. These electrodes are important for creating wearable devices that can monitor glucose levels or other substance continuously. Wrinkles also work as part of hierarchical structure which are helpful for trapping air beneath droplets of fluids. Here we incorporate wrinkles with nanoparticles which helps to make surfaces repellent to both water and oil. Such a function is important for self-cleaning surfaces and can also be used for patterning of surfaces for selective deposition of fluid.

Cosmetic treatment with botulinum toxin type A injections is the top non-surgical cosmetic procedure in the U.S. Many patients are beginning treatment at a younger age to prevent the development of facial wrinkles associated with aging. However, there is limited data to support the use of prophylactic botulinum toxin injections. Patients beginning treatment at a younger age have fewer wrinkles requiring fewer units to treat, which reduces the overall cost of treatment. Patients also maintain higher levels of self- esteem by preventing or delaying the onset of facial wrinkles that can negatively impact their appearance. This study proposes that patients receiving botulinum toxin injections at a younger age (< 35) will have higher satisfaction with treatment outcomes. By demonstrating an association between starting age of injections and patient satisfaction, this study aims to provide merit for clinical trials studying the effectiveness of prophylactic botulinum toxin injections for cosmetic indications.

Bio-interface topography strongly affects the nature and efficiency of interactions with living cells and biological molecules, making hydrogels decorated with micro and nanostructures an attractive choice for a wide range of biomedical applications. Despite the distinct advantages of protein hydrogels, literature in the field has disproportionately focused on synthetic polymers to the point that most methods are inherently incompatible with proteins and heat-sensitive molecules. We report the development of multiple biomolecule-friendly technologies to construct microstructured protein and bacteriophage (bacterial virus) hydrogels. Firstly, ordered and sphericity-controllable microbumps were obtained on the surface of protein hydrogels using polystyrene microporous templates. Addition of protein nanogels resulted in the hierarchical nano-on-micro morphology on the microbumps, exhibiting bacterial repellency 100 times stronger than a flat hydrogel surface. The developed microstructures are therefore especially suitable for antifouling applications. The microstructures created on protein hydrogels paved the way for applying honeycomb template on proteinous bacterial viruses. We developed a high-throughput method to manufacture isolated, homogenous, pure and hybrid phage microgels. The crosslinked phages in each phage-exclusive microgel self-organized and exhibited a highly-aligned nanofibrous texture. Sprays of hybrid microgels loaded with potent virulent phage effectively reduced heavy loads of multidrug resistant Escherichia coli O157:H7 on food products by 6 logs. / Thesis / Doctor of Philosophy (PhD) / Bacteriophages (bacterial viruses), also known as phages, are natural bacteria predators. These viruses act as direct missiles, each phage targeting limited groups of bacteria. In addition, phages are an endless resource for self-propagating nanoparticles that can be used as building blocks for new material. I developed a platform for manufacturing a large quantity of microscale beads made of millions of phages. These micro-beads can be sprayed on fresh produce and meat to remove bacterial contamination (with the added benefit of not affecting taste or smell). I also printed phages on substrates, like an ink. The printed phage ink evolved into a patented technology for designing phage coatings on surfaces with very high surface area, like the small structures on our fingers. This phage coating was successfully used to test the existence of bacteria in liquids.

No description available.

Le potentiel du polydiméthylsiloxane (PDMS), élastomère transparent et déformable réversiblement en temps réel, est mis en avant dans ce travail comme substrat fonctionnel dans le domaine de l’optique et du mouillage. Dans une première partie, nous avons développé des surfaces de PDMS ridées à l’aide d’instabilités de flambage, de longueurs d’onde (λ) et d’amplitude (A) variables et contrôlées, puis nous avons organisé sélectivement des nano-objets sur cette texturation de surface avec afin d’en moduler la physico-chimie. Dans une seconde partie, la génération, in situ, de nano-plots/nanoparticules d’or et d’argent à la surface de verre et de PDMS a été étudiée et caractérisée d’un point de vue optique. / The polydimethylsiloxane (PDMS), a transparent and stretchable elastomer, is put forward in this work as a functional substrate in the field of optics and wetting. In the first part, we have developed wrinkled PDMS surfaces via controlled buckling instabilities. We were able to tune both the wavelength (λ) and the amplitude (A) of the structuration on a large length scale. We have then selectively organized some nanoparticles the textured surfaces in order to modulate its physical-chemistry. In the second part, in situ generation of gold and silver nanoparticles/plots has been developed and studied both on glass PDMS surfaces and subsequently characterized optically.

The relining of deteriorated gravity flow and pressure pipes with polymeric liners is now popular practice. In the water industry, health concerns and challenges associated with re-opening water services in a lined small diameter pipe have limited the use of liners. Sanexen Environmental Services Inc. in Montreal, Canada, manufactures a cured-in-place liner system which can restore water service connections after lining from within the pipe, using a remote controlled robot. The installation of the liner within cast iron water pipes can result in the formation of geometric imperfections (wrinkles) as the external diameter of the liner often exceeds the internal diameter of the host pipe. Previous studies have suggested that the wrinkles have a detrimental effect on the structural performance of the liner. In this study, experimental and analytical investigations were conducted to evaluate further the effect of the wrinkles on the circumferential (hoop) strength of the liner. The experimental investigation involved testing 33-25 mm wide ring samples of the liner with and without wrinkles, using the split-disk test method which is defined by ASTM Standard D2290. The laboratory tests were conducted to examine the effects on the response of the liner of loading rate, cyclic loading, and presence of different wrinkle configurations. A series of two-tailed Mann-Whitney statistical tests were conducted on the obtained test data. The analytical investigation examined the behavior of two of the three types of wrinkles observed in the liner using finite element models. The results from the models were evaluated using the experimental results. This study confirmed that the wrinkles were a source of weakness in the liner as failure was initiated at the wrinkle in all the test samples. It also showed that their presence may or may not result in a reduction in the ultimate hoop tensile capacity of the liner depending on wrinkle pattern. The loading rate had no significant effect on the first cracking load of the resin within the wrinkle. However, lower ultimate hoop tensile capacities were observed at very slow loading rates. Under the 50-year cyclic loading, the resin within the wrinkle was susceptible to cracking while the jackets of the wrinkle remained intact. / Thesis (Master, Civil Engineering) -- Queen's University, 2008-09-16 22:38:10.234

Context. Real time rendering has many challenges to overcome, one of them being character realism. One way to move towards realism is to use wrinkle maps. Although already used in several games, there might be room for improvement, common practice suggests using two wrinkle maps, however, if this number can be reduced both texture usage and workload might be reduced as well. Objectives. To determine whether or not it is possible to reduce the number of wrinkle maps from two to one without having any significant impact on the perceived realism of a character. Methods. After a base character model was created, a setup in Maya were made so that dynamic wrinkles could be displayed on the character using both one and two wrinkle maps. The face were animated and rendered, displaying emotions using both techniques. A two-alternative forced choice experiment was then conducted where the participants selected which implementation displaying the same facial expression and having the same lighting condition they perceived as most realistic. Results. Results showed that some facial expressions had more of an impact of the perceived realism than others, favoring two wrinkle maps in every case where there was a significant difference. The expressions with the most impact were the ones that required different kinds of wrinkles at the same area of the face, such as the forehead, where one variant of wrinkles run at a more vertical manner and the other variant runs horizontally along the forehead. Conclusions. Using one wrinkle map can not fully replicate the effect of using two when it comes to realism. The difference on the implementations are dependant on the expression being displayed.

No description available.

Nėštumas tai fiziologinė sveikos moters būsena. Fizinio aktyvumo stoka nėštumo metu įtakoja nėščiosios savijautą. Nėščiųjų, kurios neatlieka fizinių pratimų kūno masė būna didesnė, negu reguliariai dariusios mankštą nėštumo metu. Fiziškai neaktyvių nėščiųjų širdies susitraukimų dažnis (ŠSD) būna didesnis, nei sportuojančių moterų. Pagal PSO 25 % nėščiųjų skundžiasi nugaros skausmais, susijusius su atramos judamojo aparato pokyčiais nėštumo metu. Daug dėmesio skiriama nėščiųjų sveikatingumui, tačiau nepakankamai pabrėžiama kineziterapijos nauda nėščiosios savijautai, gimdymo eigai. Literatūroje yra nemažai duomenų apie fizinių pratimų teigiamą poveikį moters organizmui, tame tarpe ir nėščiųjų, tačiau kaip taikant fizinius pratimus vandenyje keičiasi nėščiosios riebalinės raukšlės, arterinis kraujo spaudimas ir širdies susitraukimų dažnis nėra žinoma Šio tyrimo tikslas – įvertinti fizinių pratimų vandenyje poveikį nėščiosios savijautai ir kai kuriems fiziologiniams rodikliams. Tyrimo tikslui pasiekti buvo naudojami šie tyrimo metodai: 1. Anketinė apklausa; 2.Riebalinių raukšlių matavimas (kaliperiu); 3.Arterinio kraujospūdžio (mmHg) ir pulso matavimas; 4.Rufjė testas; 5. Matematinė statistika. Tyrimas buvo atliekamas Vilniaus Lietuvos vaikų jaunimo centre (LVJC). Ištirta 20 nėščiųjų, kurios lankė reguliariai užsiėmimus baseine du kartus savaitėje. Antroji grupė, kontrolinė, sudarė taip pat 20 nenėščių moterų, atsitiktinių, panašaus amžiaus, kaip ir nėščiosios. Abiems grupėms... [toliau žr. visą tekstą] / Pregnancy is a physiological appearance of a healthy woman. The lack of physical activities affects the health of pregnant woman. Those women, who do not have any physical activities, have bigger body mass, than those, who exercise regularly. Physically inactive pregnant women have bigger heart systole rate (HSR), than active once. According to PSAO 25 % of pregnant woman complain about back pains, related to changes of abutment during the period of pregnancy. A lot of attention is spared to the health of pregnant women. Unfortunately, the importance of kinezitherapy to pregnant women health is not enough emphasize. There is a lot of information in the literature about the positive effect of physical exercise to women’s´ body, including pregnant once. But, when using kinezitherapy in the water the relative body fat – body muscle mass is changing and the heart systole rate (HSR) are unknown. The importance of this research is to evaluate the effect of physical exercises in the water to a pregnant woman and some physiological indexes. The methods of this research are: 1. Questionnaires; 2. Measurement of oil wrinkles; 3. Measurement of Arterial blood pressure (mmHg) and measurement of pulse; 4.Rufje test; 5. Mathematical statistics. The research was done in Vilnius Lithuanian children and junior centre. There were examined 20 pregnant women (analyzed group) who took part in water activities 2 times a week. In the second group, (control group) there were 20 not pregnant women... [to full text]

This work is a comparative study of the various numerical techniques used for analyzing membranes. Membrane analysis is complicated by the fact that local instabilities occur in membranes in the form of small waves or ‘wrinkles’ in zones in which compression tends to appear. This is attributed to their negligible flexural stiffness. Broadly, two approaches exist in the wrinkling analysis of membranes. They are bifurcation analysis and analysis with membrane elements augmented with wrinkling models. In the former approach we can get the wrinkle details while the latter approach gives only the wrinkling zone. The present numerical strategy falls in the category of bifurcation analysis, where we make use of an energy-momentum conserving time integration algorithm in the context of a hybrid element formulation. The solution obtained through this procedure is considered to be accurate, since there are no kinematic assumptions (plane stress, etc.) made in the formulation and we achieve convergence with respect to mesh refinement. We show in this work that the wrinkling process not only depends on the stiffness matrix but also on the transient process. To show this a pseudo-dynamic scheme which is commonly used, is implemented within the hybrid formulation and we show the differences that arise between this scheme and the present method, over some benchmark problems. In this work, we also implement a wrinkling model proposed by Roddeman and finally the advantages and disadvantages of various numerical techniques are discussed.