Modified Pushdown Automata

Tato práce zavádí omezené Hromádkovy automaty jako rozšíření zásobníkových automatů. Toto rozšíření spočívá v~tom, že automat může za běhu vytvářet nové zásobníky, vkládat do nich symboly vstupní abecedy, spojovat je a porovnávat se vstupním řetězcem. Počet takto vytvořených zásobníků je omezen zvolenou konstantou n . Dále tato práce popisuje implementaci aplikace, která činnost těchto automatů realizuje a hledá posloupnost derivačních kroků, kterými určitý omezený Hromádkův automat přijme zadaný vstupní řetězec.This work introduces limited Hromádka's automata as an extension of classical pushdown automata. This extension means that the automaton is able to create new pushdowns, insert input symbols into them, join them and compare with the input string in run time. The number of such pushdowns is limited by choosen constant n . This work also describes the implementation of the application, that realizes the activity of this automata and is looking for the sequence of derivational steps, by which the automaton accepts the input string.

Tetrahedral Mesh Processing Library

Mnoho inženýrských aplikací v architektuře, medicíně a strojírenství potřebuje vytvářet modely prostoru pro potřeby různých numerických výpočtů (např. FEM simulace). Tetraedrální sítě jsou jednou z perspektivních reprezentací těchto modelů. V této práci jsou popsány různé možnosti reprezentace tetraedrálních sítí vhodné pro jejich generování a zpracování. Je navržena knihovna pro zpracování sítě, která může být charakterizována úspornou reprezentací tetraedrální sítě se zachováním možnosti aplikovat na ni efektivně topologické a geometrické algoritmy. Knihovna je implementována v jazyce C++ s použitím šablon. Časová a prostorová složitost byla porovnána s knihovnou CGAL a podle  výsledků měření má navržená knihovna nižší paměťové nároky než CGAL.Many architecure, medical and engineering applications need a spacial support for various numerical computations (i.e. FEM simulations). Tetrahedral meshes are one of perspective spatial representations for them. In this thesis, several possibilities of effective tetrahedral mesh representation for its generating and processing are described. A computer library for the mesh processing is proposed which can be characterized by memory  efficient imposition of the mesh while preserving the ability to apply topological and geometric algorithms effectively. The library is implemented in C++ language using templates. Time and space complexity of typical mesh operations is compared with CGAL library and according to measurements the proposed library has lower memory requirements than CGAL.

Isolated talonavicular arthrodesis in patients with rheumatoid arthritis of the foot and tibialis posterior tendon dysfunction

<p>Abstract</p> <p>Background</p> <p>The foot is often affected in patients with rheumatoid arthritis. Subtalar joints are involved more frequently than ankle joints. Deformities of subtalar joints often lead to painful flatfoot and valgus deformity of the heel. Major contributors to the early development of foot deformities include talonavicular joint destruction and tibialis posterior tendon dysfunction, mainly due to its rupture.</p> <p>Methods</p> <p>Between 2002 and 2005 we performed isolated talonavicular arthrodesis in 26 patients; twenty women and six men. Tibialis posterior tendon dysfunction was diagnosed preoperatively by physical examination and by MRI. Talonavicular fusion was achieved via screws in eight patients, memory staples in twelve patients and a combination of screws and memory staples in six cases. The average duration of immobilization after the surgery was four weeks, followed by rehabilitation. Full weight bearing was allowed two to three months after surgery.</p> <p>Results</p> <p>The mean age of the group at the time of the surgery was 43.6 years. MRI examination revealed a torn tendon in nine cases with no significant destruction of the talonavicular joint seen on X-rays. Mean of postoperative followup was 4.5 years (3 to 7 years). The mean of AOFAS Hindfoot score improved from 48.2 preoperatively to 88.6 points at the last postoperative followup. Eighteen patients had excellent results (none, mild occasional pain), six patients had moderate pain of the foot and two patients had severe pain in evaluation with the score. Complications included superficial wound infections in two patients and a nonunion developed in one case.</p> <p>Conclusions</p> <p>Early isolated talonavicular arthrodesis provides excellent pain relief and prevents further progression of the foot deformities in patients with rheumatoid arthritis and tibialis posterior tendon dysfunction.</p

Identification of relaxation parameter of a physical model of vein from fluid transient experiment

This paper presents a new fluid transient inflation experiment applied on a physical model of vein (short latex tube, 5mm diameter). Aim of experiments is assessment of wall viscous behaviour from attenuated pulsation of the tested sample. Experimental data obtained from dynamic test are compared with numerical simulation and a viscoelastic parameter of Haslach constitutive model is identified. It is verified that the viscoelasticity of wall has a greater impact to the damping of pulsation than the viscosity of water filling the sample and the attached capillary. Volume of sample depends on internal pressure measured by a pressure transducer. The maximum dissipation constitutive model of viscoelastic wall sample was employed for description of viscoelastic behaviour. Frequency of natural oscillation of pressure is determined by inertia of water column within the tested sample and attached capillary and by the tested specimen stiffness. The pressure pulsations are initiated by a sudden pressure drop at water surface

TET protein inhibitors: Potential and limitations

TET proteins (methylcytosine dioxygenases) play an important role in the regulation of gene expression. Dysregulation of their activity is associated with many serious pathogenic states such as oncological diseases. Regulation of their activity by specific inhibitors could represent a promising therapeutic strategy. Therefore, this review describes various types of TET protein inhibitors in terms of their inhibitory mechanism and possible applicability. The potential and possible limitations of this approach are thoroughly discussed in the context of TET protein functionality in living systems. Furthermore, possible therapeutic strategies based on the inhibition of TET proteins are presented and evaluated, especially in the field of oncological diseases