15 research outputs found
Using of Amniotic Membrane Derivatives for the Treatment of Chronic Wounds
Amniotic membrane grafts have some therapeutic potential for wounds healing. Early application of amniotic membrane turned out as beneficial in healing ulcers, burns, and dermal injuries. Since the second half of the 20th century, the autotransplants of amniotic/chorion tissue have been also used for the treatment of chronic neuropathic wounds, cornea surface injuries, pterygium and conjunctivochalasis, and dental and neurosurgical applications. The aim of this publication is to prepare a coherent overview of amniotic membrane derivatives use in the field of wound healing and also its efficacy. In total 60 publications and 39 posters from 2000-2020 were examined. In these examined publications of case studies with known study results was an assemblage of 1141 patients, and from this assemblage 977 were successfully cured. In case of posters, the assemblage is 570 patients and 513 successfully cured. From the investigated data it is clear that the treatment efficacy is very high-86% and 90%, respectively. Based on this information the use of the amniotic membrane for chronic wounds can be considered highly effective.O
Technical Development of a New Semispherical Radiofrequency Bipolar Device (RONJA): Ex Vivo and In Vivo Studies
The aim of this study is to inform about the development of a new semispherical surgical instrument for the bipolar multielectrode radiofrequency liver ablation. Present tools are universal; however they have several disadvantages such as ablation of healthy tissue, numerous needle punctures, and, therefore, longer operating procedure. Our newly designed and tested semispherical surgical tool can solve some of these disadvantages. By conducting an in vivo study on a set of 12 pigs, randomly divided into two groups, we have compared efficiency of the newly developed instrument with the commonly used device. Statistical analysis showed that there were no significant differences between the groups. On average, the tested instrument RONJA had shorter ablation time in both liver lobes and reduced the total operating time. The depth of the thermal alteration was on average 4 mm larger using the newly tested instrument. The new radiofrequency method described in this study could be used in open liver surgery for the treatment of small liver malignancies (up to 2 cm) in a single application with the aim of saving healthy liver parenchyma. Further experimental studies are needed to confirm these results before clinical application of the method in the treatment of human liver malignancies
On PID controller design using knowledge based fuzzy system
The designing of PID controllers is a frequently
discussed problem. Many of the design methods have
been developed, classic (analytical tuning methods,
optimization methods etc.) or not so common fuzzy
knowledge based methods. The aim of design methods is
in designing of controllers to achieve good setpoint
following, corresponding time response etc. In this case,
the new way of designing PID controller parameters is
created where the above mentioned knowledge system
based on the relations of Ziegler-Nichols design methods
is used, more precisely the combination of the both
Ziegler-Nichols methods. The proof of efficiency of the
proposed method and a numerical experiment is
presented including a comparison with the conventional
Ziegler-Nichols method
Statistické a Meta-heuristické modelování toků vozidel pomocí konečných směsí jednoduchých kruhových distribucí
The representation, visualization, and modeling of traffic data is at the heart of intelligent transportation systems. Different types of traffic data exist, and novel ways of their accurate representation and modeling, which are useful for further analyses, simulations, and optimizations, are sought. In this work, location-specific traffic flows are represented by finite mixtures of circular normal (von Mises) statistical distributions. The parameters of the distributions are learned from empirical data by two variants of the expectation-maximization (EM) algorithm and by a nature-inspired method, differential evolution (DE). A proposed statistical model and a fitting strategy are evaluated on real-world data sets describing traffic flows in New York City. The experimental results show that the EM algorithm is able to find model parameters that correspond to input data and that are better than their analytic estimates, while DE evolves even more accurate models. The models based on circular distributions can be represented by circular plots as a novel type of visually appealing and easily interpretable fingerprints of the underlying traffic flow patterns.Reprezentace, vizualizace a modelování dopravních dat je srdcem inteligentních dopravních systémů. Existují různé typy dat a hledají se nové způsoby jejich přesného znázornění a modelování, které jsou užitečné pro další analýzy, simulace a optimalizace. V této práci jsou lokalizační dopravní toky reprezentovány konečnými směsmi kruhových (von Mises) statistických distribucí. Parametry distribucí se určují z empirických dat dvěma variantami: E-M algoritmem a metodou heuristickou metodou diferenciální evolucí (DE). Navrhovaný statistický model a přizpůsobovací strategie jsou vyhodnocovány na reálných souborech dat popisujících dopravní toky v New Yorku. Experimentální výsledky ukazují, že algoritmus EM je schopen najít parametry modelu, které odpovídají vstupním datům a které jsou lepší než jejich analytické odhady, zatímco DE vyvíjí ještě přesnější modely. Modely založené na kruhových distribucích mohou být reprezentovány kruhovými grafy jako nový typ vizuálně přitažlivých a snadno interpretovatelných dopravních toků
Modelování hodinového dopravního toku s použitím směsi jednoduchých kruhových normálních rozdělení
Accurate modelling and representation of traffic flows is an important element of intelligent transportation systems, urban planning, and smart environments in general. In this work, location-specific hourly traffic flows are represented by finite mixtures of circular normal statistical distributions. The parameters of the finite mixtures are found by differential evolution, an evolutionary algorithm that is able to fit the statistical models to data with a high level of accuracy. The results are represented by circular plots that can be used as a form of visually appealing and easily understandable fingerprints of the underlying traffic flow patterns.Přesné modelování a reprezentace dopravních toků je důležitým prvkem inteligentních dopravních systémů, městského plánování a inteligentního prostředí obecně. V této práci jsou hodinové dopravní toky specifické pro danou lokalitu reprezentovány konečnou směsí kruhových normálních rozdělení. Parametry tohoto rozdělení směsí jsou nalezeny diferenciální evolucí, evolučním algoritmem, který je schopný přizpůsobit statistické modely datům s vysokou mírou přesnosti. Výsledky jsou reprezentovány kruhovými grafy, které lze použít jako formu vizuálně přitažlivých a snadno srozumitelných vzorů dopravního toku
Accuracy analysis of the dose delivery process while using the Xsight® Spine Tracking technology
The Accuray CyberKnife® system provides radiotherapy for the treatment of moving lung tumors, thanks to the use of the Xsight® Lung Tracking technology for monitoring the motion of the target. However, there are situations in which this technology is not able to properly track the target. Thus, the aim of the proposed work is to study the accuracy of the dose delivery process while using the Xsight® Spine Tracking technology, which helps to overcome the aforementioned issue. The CIRS Dynamic Thorax Phantom was used to simulate the motion of a spherical target (diameter 2 cm), which moves along the craniocaudal direction (motion 3 cm). Monte Carlo algorithm calculated PTV and ITV treatment plans for isocentric and non-isocentric irradiation methods. Ionization Chamber and Film Dosimetry measurements were performed to study the accuracy of the dose delivery process to the center, and to the periphery of the tumor. Results obtained through the implementation of the PTV treatment plans were used as a baseline to analyze the accuracy of dose delivery for ITV plans. Although results indicated a decrease for the dose delivered compared to the planned one, the dose delivered was not lower than the prescribed one in any of the studied cases