Neste trabalho estudamos a dinâmica assintótica não linear de algumas equações parabólicas do tipo reação-difusão sob perturbações nos parâmetros e perturbações singulares no domínio do tipo dumbbell. Mais precisamente, trataremos dos atratores provenientes destes problemas, buscaremos compreender a dependência destes conjuntos assintóticos de estados em relação ao parâmetro, investigando a continuidade com taxa dos mesmos. O programa que executaremos para obtenção da taxa de continuidade dos atratores, bem como de toda a estrutura, mostra-nos fortes propriedades de dissipatividade exponencial de alguns semigrupos / In this work we study the asymptotic nonlinear dynamical of some reaction-diffusion parabolic equations under perturbations in parameter and singular perturbations in a dumbbell domain. More precisely, we treat of the attractors from these problems, we seek understand the dependence these asymptotic set of states in relationship the parameter, investigating continuity with rate. The program that we will follow to prove the continuity of the attractors with rate well as the entire structure, we show that these semigroups possess strong exponential dissipative properties

Neste trabalho estudamos a dinâmica assintótica não linear de algumas equações parabólicas do tipo reação-difusão sob perturbações nos parâmetros e perturbações singulares no domínio do tipo dumbbell. Mais precisamente, trataremos dos atratores provenientes destes problemas, buscaremos compreender a dependência destes conjuntos assintóticos de estados em relação ao parâmetro, investigando a continuidade com taxa dos mesmos. O programa que executaremos para obtenção da taxa de continuidade dos atratores, bem como de toda a estrutura, mostra-nos fortes propriedades de dissipatividade exponencial de alguns semigrupos / In this work we study the asymptotic nonlinear dynamical of some reaction-diffusion parabolic equations under perturbations in parameter and singular perturbations in a dumbbell domain. More precisely, we treat of the attractors from these problems, we seek understand the dependence these asymptotic set of states in relationship the parameter, investigating continuity with rate. The program that we will follow to prove the continuity of the attractors with rate well as the entire structure, we show that these semigroups possess strong exponential dissipative properties

Carbonate precipitates in biofilm were investigated from hot springs near Viterbo, Italy; Salt Pond, San Salvador; and Fowl Cay Reef, Abaco, Bahamas. Features shared by hot springs and salt ponds are supersaturation with CaCO3, abundant Spirulina, and clustered acicular aragonite crystals termed “fuzzy dumbbells.” TEM and FESEM microscopy show fuzzy dumbbells contain a core of amorphous organic matter and subhedral CaCO3 microcrystals arranged in linear fabrics. Micron- to millimeter-scale microenvironments are identified by localized dissolution, the occurrence of gothic calcite inter-grown with organic filaments, and the presence of calcite in biofilm where aragonite is chemically favored. Spherical CaCO3 precipitates in reefs were anticipated, but not encountered in TEM sections of reef biofilm. In conclusion, biofilm creates the microenvironment and organic matter provides substrate for fuzzy dumbbell precipitation. TEM is a novel technique for studying the relationship between organic matter and CaCO3 precipitation, and has potential medical, industrial, and academic applications.

Title: Electromyographic analysis of the influence of vibrating dumbbell on upper extremity muscles Objective: The main purpose of this study was to compare the electric activity of m. biceps and triceps brachii, and upper and lower part of m. trapezius, during exercises both with a vibrating dumbbell, and a dumbbell without vibrations. Furthermore, our objective was to compare the muscle activity during static stress (dumbbell kept in one position), and dynamic stress with the vibrating dumbbell (moving in the elbow joint). Methods: Surface electromyography was chosen as an objectification method. Nine healthy women of age between 23 and 26 years participated in this study. A dumbbell of 1, 5 kg weight, 36 Hz vibrating frequency and 1,3 mm amplitude was used. Results: An increase of electrical activity can be observed in all assessed muscles when stimulated with vibrations. However, this increase can be considered as statistically significant only in case of static stress of the m. biceps and triceps brachii. Results also indicate high activity of the upper part of m. trapezius during exercise with activated vibrations. Key words: vibrations, vibrating dumbbell, vibration training, electromyographic analysis

A 53 year-old male presented with a one-day history of a swollen arm and dull, aching pain in the right upper extremity. The patient reported commencing exercising daily over the prior week with a modified, oscillating dumbbell; commonly referred to as a Shake Weight. Imaging revealed an occlusive thrombus in the right axillary, proximal brachial and basilic veins. The patient was treated with a 24-hour tPA infusion followed by mechanical thrombectomy, balloon angioplasty, and stent placement for a residual thrombus and stenosis. The patient was discharged the following day on warfarin and aspirin. This is the first report of effort-induced thrombosis of the upper extremity following the use of a modified, oscillating dumbbell. Due to the growing popularity of modified dumbbells and the possible risk for axillary vein thrombosis, consideration should be made to caution consumers of this potential complication.

This bachelor thesis covers the initial development of a synthesis of fullerene dimers using two different types of linking reactions. Different setups for [3+2] cycloadditions to fullerenes (Prato reaction) were tested, and for that purpose, an N-alkylated amino acid was synthesised. Hydroarylation of fullerene using Rh-catalysis was also studied, using both MIDA protected and unprotected boronic acids, as well as by using cycloaddition products. A range of model compounds in form of fulleropyrrolidenes were synthesised. Products were puried with HPLC and analysed with MALDI-MS and 1H NMR. A range of new compounds were synthesised and characterisation of them was begun. With MALDI-MS, indications that the fullerene dimer had formed were found. Using synthesised model compounds, by-products of the hydroarylation reaction were identied. / Denna kandidatuppsats behandlar påborjandet av syntesutvecklingen för bildandet av fullerendimerer genom användandet av två olika sorters länkningskemi. Olika förhållanden och reagens for [3+2]-cykloaddition till fullerener (Pratoreaktionen) studerades, och i samband med det syntetiserades en N-alkylerad aminosyra. Hydroarylering av fullerener med hjälp utav rodiumkatalys studerades även, genom reaktioner med både skyddade och oskyddade borsyror, inklusive fulleropyrrolidiner. Produkter har renats upp med HPLC och analyserats med MALDI-MS och 1H NMR. En uppsättning nya substanser har syntetiserts, men karaktäriseringen av dessa har inte slutförts. Genom användning av MALDI-MS har indikationer att fullerendimer bildats framkommit. Genom att använda syntetiserade modellsubstanser har biprodukter från hydroaryleringsreaktionen identierats.

In der vorliegenden Arbeit wurde das Phasenverhalten von harten Hantelteilchen (Dumbbells) als Funktion des Aspektverhältnisses (L*, der Quotient aus dem Abstand der Massenzentren zum Durchmesser der Kugel) und der Volumendichte untersucht. Bragg-Reflexe weisen darauf hin, das harte Dumbbells mit L* < 0.4 einen Phasenübergang von einer Fluid-artigen Phase zu einem plastischen Kristall zeigen. Die experimentellen Phasendiagramme bei L* ~ 0.24 und L*~ 0.30 sind vergleichbar mit Vorhersagen aus Monte Carlo-Simulationen. Rheologie Messungen zeigen, dass harte Dumbbells verschiedene Gleichgewichts- und Nichtgleichgewichtsphasen annehmen. Suspensionen von harten Dumbbells im Zweiphasenbereich zeigen ein einziges Fließgrenzen-Ereignis, wohingegen in der plastischen Kristallphase zwei Fließgrenzen-Ereignisse beobachtet werden. Diese, im Folgenden als „double yielding“ bezeichneten Ereignisse, hängen mit der Kristallisation der Suspensionen von harten Dumbbells zusammen. Die entsprechende Strukturentwicklung wurde mit rheo-SANS-Experimenten untersucht und mithilfe von BD Simulationen interpretiert. Es konnte gezeigt werden, dass die plastische Kristallphase polykristallin im Ruhezustand ist. Unter schwacher Scherung wird eine fcc-Schwerzwilling Struktur ausgebildet. Bei hoher Scherung formt sich eine teilweise orientierte Struktur aus gleitenden Schichten. Zwischen diesen beiden Strukturen existiert eine ungeordnete Übergangsphase. Die Scher-induzierte Strukturausbildung eintspricht dem „double yielding“ Ereignis der kristallinen harten Dumbells. Es wurde gezeigt, dass ein größeres L* (L* < 0.4) die Strukturentwicklung unter Scherung qualitativ nicht beeinflusst. Aufgrund verlangsamter Dynamik in der Nähe des Glasübergangs sind lediglich stärkere oder längere Oszillationen von Nöten, um Scher-induzierte Kristallisation zu erzeugen. Im zweiten Teil dieser Arbeit werden Systeme aus hohlen Kugeln und „Janus“-Dumbbells vorgestellt, die als kolloidale Modellsysteme dienen können. / In the present work the phase behaviour of hard dumbbells has been explored as a function of aspect ratio (L*, the center to center distance to the diameter of one composed sphere) and volume fractions using thermosensitive dumbbell-shaped microgels as the hard dumbbell model system. A fluid-to-plastic crystal phase transition indicated by Bragg reflections has been observed for L* < 0.4. The experimental phase diagrams at L* ~ 0.24 and L* ~ 0.30 are comparable to the theoretical prediction of the Monte Carlo simulations. Rheological measurements reveal that the hard dumbbells in the biphasic gap show the yielding behaviour with a single yielding event, while two yielding events have been observed for the plastic crystalline phase. The two yielding events, referred to as the double yielding behaviour, are proved to be related to the crystallization of hard dumbbells. The underlying structural evolution has been investigated by rheo-SANS experiments and the scattering data has been interpreted by BD simulations. It is demonstrated that the plastic crystal structure of the hard dumbbells is polycrystalline at rest, which has been induced into the twinned fcc structure at low strain, the partially oriented sliding layers at high strain and the intermediate state at the strain in-between. The shear-induced structural evolution corresponds to the double yielding events of the fully crystallized hard dumbbells. Additionally, we prove that the increase of L* (L* < 0.4) does not change the structural evolution of the sheared hard dumbbells. Only more extensive or longer oscillations are required to form the shear-induced crystal structures due to the slowdown of the dynamics in the vicinity of the glass transition. In a second part, the work of this thesis is extended to hollow systems composed of hollow spheres and hollow Janus dumbbells that can be used as model systems to probe phase behaviour of hollow capsules.

In this thesis, target induced glint error phenomenon is analyzed and the glint reduction techniques are evaluated. Glint error reduction performance of the methods is given in a comparative manner. First, target glint is illustrated with the dumbbell model which has two point scatterers. This illustration of the glint error builds the basic notion of target scattering centers and effect of scattering characteristics on glint error. This simplest approach is also used to understand the glint reduction methods. In an effort to evaluate the glint reduction techniques, a model based upon the concept of coherent summation of scattering complexes is used . The model is also used for introducing the basic properties of glint phenomenon. Basics of the glint phenomenon and glint reduction techniques are discussed with particular emphasis on diversity methods. Frequency diversity and spatial diversity techniques are described and investigated with generated simulation data. The diversity selection methods which are used to eliminate the erroneous data are introduced and their performances are investigated. Glint error reduction results of various scenarios including both reduction techniques and selection methods are evaluated in comparison with each other. The results indicate that significant reduction of glint error is possible by the appropriate utilization of diversity techniques in radar systems.

The goal of this thesis has been to throw light on a selection of open problems in chemical and biological physics using the general principles of statistical mechanics. These problems are all broadly concerned with the role of fluctuations in the dynamics of macromolecular systems. More specifically, they are concerned with identifying the microscopic roots of a number of interesting and unusual effects, including fractional viscoelasticity, anomalous chain cyclization dynamics in crowded environments, subdifffusion in hair bundles, symmetries in the work distributions of stretched polymers, heterogeneities in the geometries of reptation channels in polymer melts, and non-Gaussianity in the distributions of the end products of gene expression. I have shown here that all these effects are expressions of essentially the same underlying process of stochasticity, which can be described in terms of the dynamics of a point particle or a continuous curve that evolves in simple potentials under the action of white or colored Gaussian noise [8]. I have also shown that this minimal model of time-dependent behavior in condensed phases is amenable to analysis, often exactly, by path integral methods [13-15], which are naturally suited to the treatment of random processes in many-body physics. The results of such analyses are theoretical expressions for various experimentally measured quantities, comparisons with which form the basis for developing physical intuition about the phenomena under study. The general success of this approach to the study of stochasticity in biophysics and molecular biology holds out hopes of its application to other unsolved problems in these fields. These include electrical transport in DNA [143], quantum coherence in photosynthesis [144], power generation in molecular motors [145], cell signaling and chemotaxis [146], space dependent diffusion [147], and self-organization of active matter [148], to name a few. Most of these problems are characterized by non-linearities of one kind or another, so they add a new layer of complexity to the problems considered in this thesis. Although path integral and related field theoretic methods are equipped to handle such complexities, the attendant calculations are expected to be non-trivial, and the challenge to theory will be to devise effective approximation schemes for these methods, or to develop new and more sophisticated methods altogether.