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Search results for: GAMMA
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Total Domination Versus Domination in Cubic Graphs
PublicationA dominating set in a graph G is a set S of vertices of G such that every vertex not in S has a neighbor in S. Further, if every vertex of G has a neighbor in S, then S is a total dominating set of G. The domination number,γ(G), and total domination number, γ_t(G), are the minimum cardinalities of a dominating set and total dominating set, respectively, in G. The upper domination number, \Gamma(G), and the upper total domination...
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Analysis and interpretation of radiometric signals in a liquid-gas bubble flow
PublicationThe article presents the analysis of signals from a radiometric system consisting of two scintillation probes and two gamma radiation sealed sources. Calculations and interpretation were carried out for the bubble flow of the water-air mixture in the horizontal pipeline. The analysis of the obtained signals was done in time and frequency domain. In the frequency domain, a range of usable frequencies was identified, which were associated...
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APROKSYMACJE DE VYLDERA PRAWDOPODOBIEŃSTWA RUINY DLA MODELU Z CZASEM CIĄGŁYM W NIESKOŃCZONYM HORYZONCIE CZASOWYM
PublicationArtykuł przedstawia przegląd badań oraz ewolucję aproksymacji De Vyldera. Metoda ta polega na zastąpieniu procesu ryzyka poprzez inny proces ryzyka z wykładniczym rozkładem szkód tak, aby momenty pierwszych trzech rzędów przyrostu dla obu procesów były jednakowe. Idea tego oszacowania została wykorzystana w aproksymacji 4-gamma De Vyldera, w której zastosowano zastąpienie procesu ryzyka procesem ryzyka z rozkładem gamma szkód,...
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Marcinkiewicz Averages of Smooth Orthogonal Projections on Sphere
PublicationWe construct a single smooth orthogonal projection with desired localization whose average under a group action yields the decomposition of the identity operator. For any full rank lattice \Gamma ⊂ R^d , a smooth projection is localized in a neighborhood of an arbitrary precompact fundamental domain R^d / \Gamma. We also show the existence of a highly localized smooth orthogonal projection, whose Marcinkiewicz average under the...
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High frequency oscillations are associated with cognitive processing in human recognition memory
PublicationHigh frequency oscillations are associated with normal brain function, but also increasingly recognized as potential biomarkers of the epileptogenic brain. Their role in human cognition has been predominantly studied in classical gamma frequencies (30-100 Hz), which reflect neuronal network coordination involved in attention, learning and memory. Invasive brain recordings in animals and humans demonstrate that physiological oscillations...
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Stimulated by cyclodextrins high yield synthesis of azocrown analogues comprising pyrrole or imidazole residues
PublicationBadano wpływ cyklodekstryn na reakcję syntezy aza-eterów zawierających w strukturze pirol lub imidazol. Stosowano alfa-, beta- i gamma-cyklodekstryny. Uzyskane wyniki analizowano pod kątem sposobu umieszczenia cząsteczki azolu we wnęce cyklodekstryny.
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Rating mathematical models for first-pass of tracer in pCT lung studies
PublicationThis paper presents a comparison of model based on the Gauss function and the most commonly used Gamma-variate model in perfusion computed tomography (pCT) lung studies. It also verifies whether used model affects value of blood volume parameter. Three mean concentration-time curves were created from actual pCT measurements: arterial input function, blood vessels in lungs and lung parenchyma. On the basis of these mean curves we...
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Selecting wells for an optimal design of groundwater monitoring network based on monitoring priority map: A Kish Island case study
PublicationThis paper presents a novel approach, i.e. a combination of gamma test and monitoring priority map, for optimal design of groundwater monitoring network (GMN) by considering the cumulative effects of industries, human activities, and natural factors on the groundwater quality. The proposed method was successfully applied to design an optimal network for groundwater salinity monitoring on Kish Island, Persian Gulf. The priority...
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Statistical analysis of pressuremeter tests for the north transversal tunnel in Grenoble
PublicationInterpretacja wyników badań presjometrycznych metodą statystyczną. Wartości charakterystyczne. Zastosowano rozkłady normalny, log-normalny, wykładniczy, Weybulla, Gamma, Chiz, Studenta i Pareto. Określono zmienność parametrów geotechnicznych zastosowanych do projektu tunelu i współczynnika bezpieczeństwa w czasie drążenia tunelu.
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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Detekcja czasu dojścia kontrastu w obrazowaniu parametrycznym mózgu metodą DSC-MRI
PublicationW artykule tym zawarto porównanie trzech metod określania czasu dojścia kontrastu. Pierwsza z metod opiera się na załączonej literaturze, natomiast dwie zaproponowane przez autora to: dopasowanie danych do zmodyfikowanej funkcji gamma oraz detekcja bazująca na wyznaczaniu wartości progowej.
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Radioisotope measurement of selected parameters of liquid-gas flow using single detector system
PublicationTo determine the parameters of two-phase flows using radioisotopes, usually two detectors are used. Knowing the distance between them, the velocity of the dispersed phase is calculated based on time delay estimation. Such a measurement system requires the use of two gamma-ray sealed sources. But in some situations it is also possible to determine velocity of dispersed phase using only one scintillation probe and one gamma-ray source....
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New potential functions for greedy independence and coloring
PublicationA potential function $f_G$ of a finite, simple and undirected graph $G=(V,E)$ is an arbitrary function $f_G : V(G) \rightarrow \mathbb{N}_0$ that assigns a nonnegative integer to every vertex of a graph $G$. In this paper we define the iterative process of computing the step potential function $q_G$ such that $q_G(v)\leq d_G(v)$ for all $v\in V(G)$. We use this function in the development of new Caro-Wei-type and Brooks-type...
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Independent dynamics of low, intermediate, and high frequency spectral intracranial EEG activities during human memory formation
PublicationA wide spectrum of brain rhythms are engaged throughout the human cortex in cognitive functions. How the rhythms of various frequency ranges are coordinated across the space of the human cortex and time of memory processing is inconclusive. They can either be coordinated together across the frequency spectrum at the same cortical site and time or induced independently in particular bands. We used a large dataset of human intracranial...
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Measurements of Two-phase Flows in Pipelines Using Radioisotopes and Statistical Signal Processing
PublicationThis paper presents an application of radiotracers and gamma absorption method in two-phase flow measurements in pipelines. Two different methods were implemented to analysis of acquired signals. Investigated methods are based on the cross-correlation function and the phase of the cross-spectral density distribution. The examples presented in the article illustrate the application of the radioisotopes to evaluation of liquid-gas...
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Comparison of noise reduction methods in radiometric correlation measurements of two-phase liquid-gas flows
PublicationTwo-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air...
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Liczba wiązania grafów krawędziowych
PublicationLiczba wiązania b(G) grafu G jest mocą najmniejszego zbioru krawędzi, których usunięcie z grafu G prowadzi do grafu o liczbie dominowania większej niż gamma(G). Pokazujemy ogólne ograniczenia dla liczby wiązania grafu krawędziowego dowolnego grafu spójnego i grafu pełnego. Ponadto rozważamy liczbę wiązania grafów krawędziowych dla szczególnych przypadków drzew.
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The influence of new MDP and tuftsin analogs on cytokines levels in experimentally induced sepsis
PublicationPrzedstawiono wpływ analogów MDP z tuftsyną na poziom cytokin: TNF(alfa), IL6, IL10, INF(gamma). Wszystkie badane związki działały aktywująco na makrofagi narządowe i niezwykle efektywnie na monocyty krwi obwodowej. Na podstawie otrzymanych wyników można stwierdzić, że badane związki są za słabe by mogły działać jako samodzielne terapeutyki. ich zastosowanie w klinice upatruje się raczej w formie adjuwantów.
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Evaluation of immune responses in sheep induced by DNA immunization with genes encoding GRA1, GRA4, GRA6 and GRA7 antigens of Toxoplasma gondii
PublicationW niniejszej pracy oszacowano odpowiedź immunologiczną owiec szczepionych domięśniowo szczepionkami DNA zawierającymi geny kodujące cztery antygeny granul o dużej gęstości (GAR1, GRA4, GRA6 oraz GRA7) Toxoplasma gondii. Wykazano, iż wykorzystanie DNA plazmidu pGRA7 indukuje znaczący poziom przeciwciał IgG-2 anty-GRA7 oraz IFN-gammma, podczas gdy iniekcja pGRA1, pGRA4 oraz pGRA6 stymuluje odpowiedź przeciwciał IgG1 z ograniczoną...
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Pathological and physiological high-frequency oscillations in focal human epilepsy
PublicationHigh-frequency oscillations (HFO; gamma: 40-100 Hz, ripples: 100-200 Hz, and fast ripples: 250-500 Hz) have been widely studied in health and disease. These phenomena may serve as biomarkers for epileptic brain; however, a means of differentiating between pathological and normal physiological HFO is essential. We categorized task-induced physiological HFO during periods of HFO induced by a visual or motor task by measuring frequency,...
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Dysfunctional prefrontal cortical network activity and interactions following cannabinoid receptor activation.
PublicationCoordinated activity spanning anatomically distributed neuronal networks underpins cognition and mediates limbic-cortical interactions during learning, memory, and decision-making. We used CP55940, a potent agonist of brain cannabinoid receptors known to disrupt coordinated activity in hippocampus, to investigate the roles of network oscillations during hippocampal and medial prefrontal cortical (mPFC) interactions in rats. During...
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Human verbal memory encoding is hierarchically distributed in a continuous processing stream
PublicationProcessing of memory is supported by coordinated activity in a network of sensory, association, and motor brain regions. It remains a major challenge to determine where memory is encoded for later retrieval. Here we used direct intracranial brain recordings from epilepsy patients performing free recall tasks to determine the temporal pattern and anatomical distribution of verbal memory encoding across the entire human cortex. High...
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Social Convergence in Nordic NUTS-3 Regions
PublicationGeographical proximity, common historical roots and collaboration within the Nordic Council make the Nordic countries, often wrongly treated as monoliths. However, in reality, Nordic regions differ in terms of broadly defined social and economic development. Issues concerning the standard of living are one of the priorities of the Helsinki Treaty signed by Nordic countries. The main goal of this paper is to analyze the existence...
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The Implementation of the Taxonomic Spatial Measure of Development in the Analysis of Convergence in the Standard of Living
PublicationThe main goal of this paper is to analyse the existence of the social convergence in the European Union between 19952012. The social convergence refers to a reduction in the dispersion of the standard of living across countries. A taxonomic spatial measure of development was used as the standard of living approximation. The use of the new approach proposed by E. Antczak allowed for an explanation of the disparities in the analysed...
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Radionuclides activity and effective doses referred to geological formations
PublicationNaturally occurring radioactive materials (NORM) are present in Earth’s crust and they caused natural background radiation, variable in different regions. Liquid, gas and solid radionuclides emit three types of radiation – alpha, beta and gamma. Fluctuations of natural radioactivity in different geological formations in the world and in Poland were compared in relation to radiological hazard. Also drilling cuttings from boreholes...
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Social convergence in Nordic countries at regional level
PublicationResearch background: Geographical proximity, common historical roots and collaboration within the Nordic Council cause the Nordic countries to be often wrongly treated as monoliths. However, in reality, Nordic regions differ in terms of broadly defined social and economic development. Issues concerning the standard of living are one of the priorities of the Helsinki Treaty signed by Nordic countries. Purpose of the article: The...
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Tomografia perfuzyjna pCT w diagnostyce cukrzycowej mikroangiopatii płucnej
PublicationNiniejsza rozprawa jest poświęcona zagadnieniom diagnostyki mikroangiopatii płucnej ze szczególnym uwzględnieniem perfuzyjnej tomografii komputerowej (pCT). Retinopatia, nefropatia i neuropatia są znanymi powikłaniami cukrzycy. Mało poznany jest wpływ cukrzycy na funkcjonowanie układu oddechowego. Obecnie stosowana metoda diagnostyki cukrzycowej mikroangiopatii płucnej ma ograniczoną wiarygodność. W rozprawie została przedstawiona...
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Development of methods improving storage stability of bitumen modified with ground tire rubber: A review
PublicationThe following paper presents an overview of methods for improving the storage stability at high temperature of rubber modified bitumen. The storage stability of the rubber modified bitumen can be improved by using a various types of modifiers that form the bonds between the components of these binders. The increase in stability can also be achieved by using crumbrubber surface-activated by furaldehyde or ground tire rubber (GTR)...
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Desmuramylopeptydy - struktura i aktywność biologiczna = Desmuramylpeptide - structure and biological activity
PublicationWśród fragmentów bakteryjnych ścian komórkowych, ktore wzbudzają duże zainteresowanie, są tak zwane desmuramylopeptydy. Są to cząsteczki nie zawierające reszty kwasu muraminowego. W niniejszym artykule opisano desmuramylopeptydy, które z uwagi na swoje właściwości farmakologiczne, takie jak stymulowanie niespecyficznej odporności przeciwbakteryjnej, aktywność przeciwwirusową i przeciwnowotworową oraz synergistyczne oddziaływanie...
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Radioisotope measurements of the liquid-gas flow in the horizontal pipeline using phase method
PublicationThe paper presents application of the gamma-absorption method to a two-phase liquid-gas flow investigation in a horizontal pipeline. The water-air mixture was examined by a set of two Am-241 radioactive sources and two NaI(Tl) scintillation probes. For analysis of the electrical signals obtained from detectors the cross-spectral density function (CSDF) was applied. Results of the gas phase average velocity measurements for CSDF...
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The uses of the pressuremeter test for the design of north transversal tunnel in Grenoble
PublicationWyniki otrzymane z badań presjometrycznych wykorzystano do obliczeń statycznych za pomocą programu Extreme, którym wyznacza się wartość średnią X, odchylenie standardowe, wartość charakterystyczną Xk i rozkład teoretyczny każdego z parametrów. Obliczono wartość charakterystyczną kąta tarcia wewnętrznego dla każdego rodzaju gruntów z prawdopodobieństwem Alfa (równym 5%). Badano rozkłady: normalny, log normalny, wykładniczy, Weybulla,...
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Signals Features Extraction in Radioisotope Liquid-Gas Flow Measurements using Autocorrelation Function
PublicationKnowledge of the two-phase flow structure is essential for the proper conduct of industrial processes. Description of liquid-gas flow regimes is possible by using of data analysis in time, frequency, or state-space domain. In this research studies, the autocorrelation function is applied for analysis of signals obtained for liquid-gas flow by use gamma-ray absorption. The experiments were carried out on the laboratory hydraulic...
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RecA Proteins from Deinococcus geothermalis and Deinococcus murrayi - Cloning, Purification and Biochemical Characterisation
PublicationEscherichia coli RecA plays a crucial role in recombinational processes, the induction of SOS response and mutagenic lesion bypasses. It has also been demonstrated that RecA protein is indispensable when it comes to the reassembly of shattered chromosomes in gamma-irradiated Deinococcus radiodurans, one of the most radiation-resistant organisms known. Moreover, some functional differences between E. coli and D. radiodurans RecA...
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Unusual odd-chain and trans-octadecenoic fatty acids in tissues of feral European beaver (Castor fiber), Eurasian badger (Meles meles) and raccoon dog (Nyctereutes procyonoides).
PublicationW lipidach wyizolowanych z różnych partii ciała bobrów, borsuków i jenotów stwierdzono obecność znaczących ilości niezwykłych jak na zwierzęta jednożołądkowe kwasów tłuszczowych - nieparzystowęglowych nasyconych i jednonienasyconych KT (15:0, 17:0, 15:1 i 17:1) oraz (w lipidach tkanek bobra i jenota) oktadecenowych KT konfiguracji trans, w tym kwasu wakcenowego - KT charakterystycznych dla tkanek i mleka przeżuwaczy. Obecność tych...
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Application of ANN and PCA to two-phase flow evaluation using radioisotopes
PublicationIn the two-phase flow measurements a method involving the absorption of gamma radiation can be applied among others. Analysis of the signals from the scintillation probes can be used to determine the number of flow parameters and to recognize flow structure. Three types of flow regimes as plug, bubble, and transitional plug – bubble flows were considered in this work. The article shows how features of the signals in the time and...
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Visualizing spatially decomposed intermolecular correlations in the infrared spectra of aprotic liquids
PublicationInfrared (IR) spectroscopy is commonly used to study intermolecular interactions in the liquid phase, including solvation phenomena. On the other hand, ab initio molecular dynamics (AIMD) simulations offer the possibility to obtain IR spectra from first principles. Surpassing the experiment, AIMD simulations can deliver additional information on the spatial intermolecular correlations underlying the IR spectrum of the liquid. Although...
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Modelowanie perfuzji mózgu w badaniach MRI.
PublicationPraca dotyczy dynamicznego badania mózgu z wykorzystaniem techniki MRI (badanie perfuzji). W rezultacie pomiarów, tj. czasowej sekwencji skanów MRI w odpowiedzi na podanie znacznika zmieniajšcego właciwoci magnetyczne tkanek, wyznaczony zostaje model procesu perfuzji. Dla badanego procesu perfuzji opracowano model nieparametryczny (odpowied aproksymowana niezupełnš funkcjš gamma o 3 parametrach) oraz dwukompartmentowy model...
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Functional Bi2O3/Gd2O3 Silica-Coated Structures for Improvement of Early Age and Radiation Shielding Performance of Cement Pastes
PublicationThis study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated...
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Obróbka graficzna obrazu w nowoczesnych systemach diagnostyki sieci trakcyjnej jezdnej
PublicationW artykule autorzy przedstawiają założenia nowej metody bezkontaktowego pomiaru położenia przewodów jezdnych sieci trakcyjnej, a także pokazują jakie znaczenie w tej metodzie ma komputerowa analiza obrazu pozyskiwanego z kamery. Problemem technik wizyjnych jest zmienność parametrów obrazu wejściowego (jasność, kontrast, zakres widma, krzywa gamma i in.), które są zależne od zmieniających się warunków oświetlenia zewnętrznego związanych...
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Quantum security and theory of decoherence
PublicationWe sketch a relation between two crucial, yet independent, fields in quantum information research, viz. quantum decoherence and quantum cryptography. We investigate here how the standard cryptographic assumption of shielded laboratory, stating that data generated by a secure quantum device remain private unless explicitly published, is disturbed by the einselection mechanism of quantum Darwinism explaining the measurement process...
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Parametric versus nonparametric modelling of dynamic susceptibility contrast enhanced MRI based data
PublicationDynamic tracking of a bolus of a paramagnetic agent (dynamic susceptibility contract - DSC) in MRI (magnetic resonance imaging) measurements is successfully used for assessment of the tissue perfusion and the other features and functions of the brain (i.e. cerebral blood flow - CBF, cerebral blood volume - CBV, mean transit time - MTT). The parametric and nonparametric approaches to the identification of MRI models are presented...
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Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
PublicationKnowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated...
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A new approach to β-decays studies impacting nuclear physics and astrophysics: The PANDORA setup
PublicationTheory predicts that lifetimes of β-radionuclides can change dramatically as a function of their ionization state. Experiments performed in Storage Rings on highly ionized atom have proven nuclei can change their beta decay lifetime up to several orders of magnitude. The PANDORA (Plasmas for Astrophysics, Nuclear Decay Observation and Radiation for Archaeometry) experiment is now conceived to measure, for the first time, nuclear...
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Morphology and mechanical properties of polyamide/clay nanocomposites toughened with NBR/NBR-g-GMA: A comparative study
PublicationThis work highlights the importance of nanoclay dispersion state in the nanocomposites containing polyamide 6 (PA6), nanoclay and elastomers as well as clay localization at the interface of thermoplastic/elastomer. Morphology and mechanical properties of a series of nanocomposites containing acrylonitrile butadiene rubber (NBR), glycidyl methacrylate-grafted NBR (NBR-g-GMA), and combined NBR/NBR-g-GMA were compared and discussed...
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Hybrid analogues of SFTI-1 modified in P1 position by β- and γ-amino acids and N-substituted β-alanines
PublicationA series of compounds containing either non-proteinogenic beta-/gamma-amino acids or N-substituted beta-alanine residues (beta-peptoid units) in P-1 specificity position were synthesized based on the structure of sunflower trypsin inhibitor 1 (SFTI-1). The compounds were synthesized on a solid support; the N-substituted beta-alanines (beta Nhlys and beta Nhphe) were introduced into a peptidomimetic chain via a two-step approach...
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Superconductivity in the intermetallic compound Zr5Al4
PublicationPolycrystalline Zr5Al4 was synthesized using the arc-melting method. Powder X-ray diffraction confirms the previously reported crystal structure of the Ti5Ga4-type P63/mcm with lattice parameters: a = 8.4312(6) A , and c = 5.7752(8) A . Electrical resistivity and low-temperature magnetic susceptibility measurements indicate that Zr5Al4 exhibits superconducting behavior below 2 K. The normalized heat capacity jump at Tc= 1.82 K...
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Natural radioactivity of solid and liquid phases from shale oil and gas prospection in Pomerania
PublicationIonizing radiation intensity data and estimation of equivalent absorbed dose from solid and liquid samples from prospection of shale gas and oil at selected sites in Pomerania are presented. Naturally occurring radioactive materials (NORM) are associated with geological formations or fluids and can be enhanced during oil and gas production. They appear in e.g. drilling cuttings, flow back water, produced water, scale and sludge....
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Accumulation of radioisotopes and heavy metals in selected species of mushrooms
PublicationSeven species of forest mushrooms from different regions of Poland (edible: Imleria badia, Cantharellus cibarius, Xerocomus subtomentosus, Suillus luteus and inedible by humans but being food for animals: Paxillus involutus, Tylopilus felleus and Russula emetica) were analyzed for radioisotope activity (Cs-137, K-40, Bi-214 and Pb-210) as well as concentrations of heavy metals (aluminum, chromium, cadmium, manganese, iron, lead,...
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Performance of a new commercial high-definition 3D patient specific quality assurance system for CyberKnife robotic radiotherapy and radiosurgery
PublicationConventional two dimensional and low-definition measurement techniques for dosimetric verification of radiotherapy treatment deliveries are no longer adequate in the era of hypofractionation and extremely high dose gradients. New quality assurance (QA) tools with 3D capability and high definition are urgently needed. The purpose of this study was to evaluate the performance of one of the first such commercial systems as applied...
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Algorytm automatycznego rozpoznawania treści tablicy rejestracyjnej i wyszukiwania pojazdów w bazie danych
PublicationReferat opisuje algorytm rozpoznawania znaków zawartych w tablicy rejestracyjnej oraz współpracę algorytmu z bazą danych tablic rejestracyjnych. Przedstawiono metodę rozpoznawania znaków wykorzystującą obraz ze zlokalizowaną wcześniej tablicą rejestracyjną. Obraz tablicy jest poddawany przetwarzaniu wstępnemu. Wykonywane są operacje automatycznego wykrywania rotacji tablicy, normalizowania histogramu, dostosowania współczynnika...