106 research outputs found

    Static provision of baroque church

    Get PDF
    Diplomová práce řeší statické zajištění barokního kostela sv. Jakuba v Městečku Trnávce. Kostel byl postaven roku 1752 v barokním slohu na místě původního románského kostela. Jedná se o zděný jednolodní objekt o půdorysných rozměrech cca 46 × 20 m. Na loď kostela navazuje mohutná hranolová věž o výšce cca 34 m. Důvodem pro sanaci kostela je vznik trhlin v nosném zdivu a v klenbě způsobený nedostatečným prostorovým ztužením objektu. Objekt bude zesílen horizontálním a příčným předpětím. Jsou navržena volná předpínací lana, tzv. monostrandy, s využitím metody náhradních kabelových kanálků. Jejich použitím se zabrání dalším derformacím a zajistí se tak zvýšení celkové tuhosti objektu.The master´s thesis solves a static provision of the Baroque church of Saint James in Městečko Trnávka. The church was built in 1752 in Baroque style on the place of the original Romanesque church. It is a single-nave building with dimensions of about 46 × 20 m. The nave is followed by a massive square tower with a height of about 34 m. The reason for the restoration of the church are cracks in the external masonry and arch due to small space stiffness. The building will be reinforced by horizontal and transverse prestressing. They are designed prestressing tendons, called monostrands, using method of alternative cable channels. It will help to avoid other derformations and it will increase a stiffness of the structure.

    REKONSTRUKCE SMĚRŮ PROUDĚNÍ POMOCÍ MĚŘENÍ ANIZOTROPIE MAGNETICKÉ SUSCEPTIBILITY VE FLUVIÁLNÍCH SEDIMENTECH OCHOZSKÉ JESKYNĚ, MORAVSKÝ KRAS

    Get PDF
    Anisotropy of magnetic susceptibility (AMS) measurements were used to determine the flow directions in fine deposits preserved in the Ochozská Cave (southern segment of the Moravian Karst). This approach was first verified in two sedimentary sections located in the main corridor of the cave, where is no doubt about paleoflow directions. Subsequently, the AMS was measured in the fine deposits preserved in sections located in the Zkamenělá řeka Corridor and U kuele Corridor. The interpreted paleoflow directions are in both sections from the NNE to the SSW

    MORFOLOGIE POLOSLEPÉHO HOSTĚNICKÉHO ÚDOLÍ A JEHO VZTAH KE KRASOVÝM JEVŮM V JIŽNÍ ČÁSTI MORAVSKÉHO KRASU

    Get PDF
    Morphology of the halfblind Hostěnice Valley was established based on electric resistivity sounding and seismic measurements. A limestone bottom of the valley is situated at altitude 350 m a.s.l bellow ca. 30 m thick fluvial or lacustrine clayey and sandy deposits. At the limestone and non-karstic boundary a 20 m high step was formed. The bottom of the valley (350 m a.s.l.) corresponds with the older cave corridors in the nearby Ochozská Cave forming probably Pliocene cave level. During the Quaternary main cave passages were deepened leaving the older corridors in a hanging position

    TERCIÉRNÍ JESKYNNÍ SEDIMENTY V LOMU MALÁ DOHODA U HOLŠTEJNA V MORAVSKÉM KRASU

    Get PDF
    Tertiary fluvial sediments were found in two cave channels exposed in a limestone quarry named Malá dohoda at Holštejn near the northern termination of the Moravian Karst. The age of these cave deposits is the Lower Miocene (Ottnangian) based on lithology and heavy mineral assemblage. Subsurface fluvial activity documented by the high position (495 m a.s.l.) of these filled cave channels opens new questions concerning the pre-Badenian fluvial processes and speleogenesis in the Moravian Karst

    Palaeomagnetic and U-series Dating of Cave Sediments in Baradla Cave, Hungary

    Get PDF
    Drobnozrnati siliklastični sedimenti glavne galerije in gornjega nivoja jame Baradla, izkazujejo veliko homogenost v zgradbi in sedimentnih teksturah. Paleomagnetne analize kažejo normalno polarizacijo vseh vzorcev, kar pomeni starost, ki je mlajša od meje Brunhes/Matuyama pri 780 ka. Siga oz. stalagmiti, ki pokrivajo siliklaste v gornjem jamskem nivoju, vsebujejo tudi reverzno polarizirane vzorce, katerih datacije z uran torijevo metodo kažejo na starost 114-115 ka, kar nakazuje na dogodek Blake. Homogenost sedimentov lahko razložimo z enkratnim dogodkom, kjer je zapolnitev s sedimentom povzročil zastoj pretoka. Temu so lahko botrovali geološki (npr. podor) ali paleoklimatski vzroki pred približno 130-150 ka, kolikor je tudi najvišja starost sedientov v sistemu Domica-Baradla izmerjena z metodo uran-torij. Fine-grained siliciclastic sediments from the main gallery and upper cave level show nearly uniform composition and sedimentary textures. Palaeomagnetic analysis indicates normal magnetic polarisation of all samples, i.e. the age younger than Brunhes/Matuyama boundary at 780 ka. Flowstone/stalagmite covering siliciclastics in the upper cave level contains reverse polarised samples dated by U-series method to about 114–115 ka, which can be identified as the Blake Event. The uniform composition of sediments can indicate the infill of the cave during a single event caused by the blockage of drainage routes due to geological (collapse) or palaeoclimatic (ice) changes, which took part before ca 130 to 150 ka as indicating by the oldest U-series data from the whole Domica–Baradla Cave System.

    Selected Analytical Techniques of Solid State, Structure Identification, and Dissolution Testing in Drug Life Cycle

    Get PDF
    The textbook provides an overview of the main techniques applied in pharmaceutical industry, with the focus on solid-state analysis. It discusses spectral methods, thermal analysis, and dissolution testing, explains the theoretical background for each method and shows practical examples from a real-life drug-design and quality control applications. The textbook is thus intended for both pharmacy students and early career professionals

    New Role for L-Arginine in Regulation of Inducible Nitric-Oxide-Synthase-Derived Superoxide Anion Production in Raw 264.7 Macrophages

    Get PDF
    Dietary supplementation with L-arginine was shown to improve immune responses in various inflammatory models. However, the molecular mechanisms underlying L-arginine effects on immune cells remain unrecognized. Herein, we tested the hypothesis that a limitation of L-arginine could lead to the uncoupled state of murine macrophage inducible nitric oxide synthase and, therefore, increase inducible nitric-oxide-synthase-derived superoxide anion formation. Importantly, we demonstrated that L-arginine dose- and time dependently potentiated superoxide anion production in bacterial endotoxin-stimulated macrophages, although it did not influence NADPH oxidase expression and activity. Detailed analysis of macrophage activation showed the time dependence between LPS-induced iNOS expression and increased O2∙− formation. Moreover, downregulation of macrophage iNOS expression, as well as the inhibition of iNOS activity by NOS inhibitors, unveiled an important role of this enzyme in controlling O2∙− and peroxynitrite formation during macrophage stimulation. In conclusion, our data demonstrated that simultaneous induction of NADPH oxidase, together with the iNOS enzyme, can result in the uncoupled state of iNOS resulting in the production of functionally important levels of O2∙− soon after macrophage activation with LPS. Moreover, we demonstrated, for the first time that increased concentrations of L-arginine further potentiate iNOS-dependent O2∙− formation in inflammatory macrophages

    REKONSTRUKCE PALEOHYDROGRAFIE NA ZÁKLADĚ DATOVÁNÍ SEDIMENTŮ HOLŠTEJNSKÉ JESKYNĚ (MORAVSKÝ KRAS)

    Get PDF
    Large sections in cave deposits are exposed in the Holštejnská Cave in the Moravian Karst. The periods of fluvial activity alternated with periods of speleothem deposition. The study of the genesis and age of these cave deposits poses a clue to the reconstruction of development of the Holštejnská Cave and of local paleohydrographic history. The time of deposition was determined by U-series dating of speleothems, 10Be and 26Al dating of quartz pebbles, radiocarbon dating of charcoal and measurement of paleomagnetic record in both clastic sediments and speleothems. The fluvial sediments were deposited during the Early, Middle and Late Pleistocene in the cave. The age of oldest cave sediment sequence deposited by a subsurface stream indicates that the local hydrographic situation has changed later than 0.8 Ma

    Dielectric properties of graphene/nano-Fe2O3 filled poly (vinyl alcohol)/ Chitosan blends

    Get PDF
    Novel nanocomposites based on Poly (vinyl alcohol) (PVA), Chitosan (CS), Graphene quantum dots (GQDs) and iron oxide (Fe2O3) nanoparticles (NPs) have been synthesized by solution casting method. The structural mod-ifications and morphological studies were carried out by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Scanning electron microscopy/Energy-dispersive X-ray (SEM/EDX) techniques. The results confirm the microscopic interactions and sphere-like morphology of the nanocomposites due to the presence of GQDs and Fe2O3 within the polymer blend. The thermal stability with almost 25% leftover residue for higher nanofillers loading in the nanocomposite was estimated by thermo-gravimetric analysis (TGA). Moreover, the frequency and temperature-dependent dielectric properties were investigated. The dielectric constant and loss tangent values are greatly influenced by reinforcement of GQDs/Fe2O3 and the obtained values were in the range of-104 and-101, respectively at 150 degrees C and 50 Hz. The rise in ac conductivity i.e., 9.8 x 10-4 (S/m) with increasing nanofiller loadings suggests the reduction in capacitive reactance and impedance. However, the semi-circular arcs are observed in the cole-cole plot where the fitted impedance data along with the equivalent circuit is also presented. The reduction of bulk resistance and impedance on increasing the nanofiller loadings with enhanced dielectric properties signifies the use of PVA/CS/GQDs/Fe2O3 nanocomposites as a potential material for energy storage applications.Novel nanocomposites based on Poly (vinyl alcohol) (PVA), Chitosan (CS), Graphene quantum dots (GQDs) and iron oxide (Fe2O3) nanoparticles (NPs) have been synthesized by solution casting method. The structural mod-ifications and morphological studies were carried out by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Scanning electron microscopy/Energy-dispersive X-ray (SEM/EDX) techniques. The results confirm the microscopic interactions and sphere-like morphology of the nanocomposites due to the presence of GQDs and Fe2O3 within the polymer blend. The thermal stability with almost 25% leftover residue for higher nanofillers loading in the nanocomposite was estimated by thermo-gravimetric analysis (TGA). Moreover, the frequency and temperature-dependent dielectric properties were investigated. The dielectric constant and loss tangent values are greatly influenced by reinforcement of GQDs/Fe2O3 and the obtained values were in the range of-104 and-101, respectively at 150 degrees C and 50 Hz. The rise in ac conductivity i.e., 9.8 x 10-4 (S/m) with increasing nanofiller loadings suggests the reduction in capacitive reactance and impedance. However, the semi-circular arcs are observed in the cole-cole plot where the fitted impedance data along with the equivalent circuit is also presented. The reduction of bulk resistance and impedance on increasing the nanofiller loadings with enhanced dielectric properties signifies the use of PVA/CS/GQDs/Fe2O3 nanocomposites as a potential material for energy storage applications

    Magnetic record associated with tree ring density: Possible climate proxy

    Get PDF
    A magnetic signature of tree rings was tested as a potential paleo-climatic indicator. We examined wood from sequoia tree, located in Mountain Home State Forest, California, whose tree ring record spans over the period 600 – 1700 A.D. We measured low and high-field magnetic susceptibility, the natural remanent magnetization (NRM), saturation isothermal remanent magnetization (SIRM), and stability against thermal and alternating field (AF) demagnetization. Magnetic investigation of the 200 mm long sequoia material suggests that magnetic efficiency of natural remanence may be a sensitive paleoclimate indicator because it is substantially higher (in average >1%) during the Medieval Warm Epoch (700–1300 A.D.) than during the Little Ice Age (1300–1850 A.D.) where it is <1%. Diamagnetic behavior has been noted to be prevalent in regions with higher tree ring density. The mineralogical nature of the remanence carrier was not directly detected but maghemite is suggested due to low coercivity and absence of Verwey transition. Tree ring density, along with the wood's magnetic remanence efficiency, records the Little Ice Age (LIA) well documented in Europe. Such a record suggests that the European LIA was a global phenomenon. Magnetic analysis of the thermal stability reveals the blocking temperatures near 200 degree C. This phenomenon suggests that the remanent component in this tree may be thermal in origin and was controlled by local thermal condition
    corecore