THE ROLE OF TECHNICAL AND NATURAL SCIENCES IN STONE MONUMENTS CARE

Stone monuments maintenance requires the systematic approach which should be based on the cooperation among specialist through more branches, especially from humanities, natural and technical sciences. The main aim of this article is to present the benefit of the cooperation among geologists and civil engineers and share preliminary results of the Czech Ministry of Culture project DG20P02OVV021 “Stone surface topography and its application in stone element restoration field”. Historic stone surfaces often contain stonemasons tool traces as an undoubtable part of historical monument value. The study and protection of the testimony of past is therefore very important. As a part of our project, we are conducting field and laboratory research of historic stone surfaces bearing the original tool traces. The studied area is the Prague urban conservation zone for its stone monuments richness from Romanesque to present days. First, the geological research of the stone masonry surface is conducted in the cooperation with archaeologists. The tool traces are documented, and the state of stone is described. Because of the negative influence of weathering processes on the stone durability, respectively tool traces, we decided to monitor the chosen historical stone surface using the hyperspectral analysis. Based on the analysis results we will be able to better understand the behaviour of stone surface and traces on it during the time

A highly non-smooth norm on Hilbert space

We show that there exists a familyF of unit balls in the Hilbert spacel 2 such that ∪F is dense inl 2 but the complement of ∪F is large in the sense of measure. In an appendix, we present a considerable simplification of the proof due to Preiss. As a corollary, we prove that there is an equivalent normp onl 2 such that the set of points wherep is Fréchet differentiable is Aronszajn null. This disproves a conjecture of Borwein and Noll in a very strong sens

TESTING OF CLOSE-RANGE PHOTOGRAMMETRY AND LASER SCANNING FOR EASY DOCUMENTATION OF HISTORICAL OBJECTS AND BUILDINGS PARTS

In contemporary times, technology has dramatically simplified the process of documenting cultural heritage objects. This paper aims to illustrate modern methodologies for documenting historical monuments by applying advanced technologies, as these case studies show. Two technologies were used: laser scanning and digital photogrammetry. The first subject of our study was a historically significant 16th-century building located in Jachymov, situated in the North-West region of the Czech Republic. The object was documented by laser scanning (BLK360) and using a standard digital camera Canon Powershot SX230 HS. The laser scanning data were post-processed using Cyclone Register 360 Plus, while photogrammetric point clouds were generated with Agisoft Metashape. The second objects were a building and a sculpture in the historical UNESCO city of Telč; here laser scanning instruments, digital photogrammetry and a new one low-cost ViDoc documentation system were use. Our study is focused on analyzing the sets of point clouds obtained from the data processing, conducted using CloudCompare to draw insights and conclusions. It turns out that the rapid development of techniques and technology makes it possible to use low-cost devices for sufficiently accurate and fast documentation; however, the mentioned ViDOC device can only be used for very close and small objects up to about 5 meters. For the documentation of sculptures, classic close-range photogrammetry is especially appropriate; for the documentation of buildings, laser scanners are suitable; the problem here is with hidden spaces and it is often necessary to use either a platform or a combination with photogrammetry using a drone, especially for the upper parts of the object

Pollinator movement and orientation at small spatial scales

Opylování je zajímavá a komplexní interakce mezi hmyzem a rostlinou, která je nezbytná pro celou škálu roslin a živočichů. Pestřenkovití (Diptera: Syrphidae) a včely (Hymenoptera: Anthophila) jsou jedni z nejčastějších opylovačů ve středoevropské krajině a většinově se podílí na opylování místních rostlin. Pro zajištění opylení je nutný přesun opylovače z jednoho květu rostliny konkrétního druhu na další květ rostliny stejného druhu. Tento pohyb je ovlivňován celou řadou faktorů vycházejících jak z vlastností prostředí, tak z vlastností opylovače samotného. Tato práce si klade za cíl prozkoumat vlastnosti ovlivňující přelet opylovače mezi rostlinami na malých prostorových škálách, utřídit poznatky o vlivu vlastností prostředí i vlastnostech opylovače, srovnat rozdíly mezi skupinou pestřenkovitých a včel a naznačit možné směry dalšího výzkumu v této oblasti. Klíčová slova: opylování, pestřenky, včely, Syrphidae, Anthophila, pohybPollination is interesting andcomplex interaction between insects and plants which is essential for a wide spectrum of plants and animals. Hoverflies (Diptera: Syrphidae) and bees (Hymenoptera: Anthophila) are one of the most common pollinators in the Central Europe and are mostly involved in pollination of local plants. To maintain pollination, it is necessary the movement of pollinator from one flower of a specific species to another flower of the same species. This movement is affected by a number of factors based on both the environmental and pollinator traits. The aim of this work is to explore the nature of traits affecting pollinator flight between plants on small spatial scales, to classify the knowledge about the influence of pollinator and ambient effects to compare the differences between hoverflies and bees and suggest further possible fields of research. Keywords: pollination, hoverflies, bees, Syrphidae, Anthophila, movementKatedra zoologieDepartment of ZoologyPřírodovědecká fakultaFaculty of Scienc

Schopnost diskriminace květních morfotypů u pestřenek

Atraktivita květů pro opylovače je zprostředkována několika květními znaky. Schopnost rozlišovat květiny na základě těchto květních vlastností je velmi důležitá pro reprodukci květin a výživu a následně i reprodukci opylovačů. Na modelovém organismu Eristalis tenax jsme v laboratorních podmínkách testovali tři květní znaky - barvu, velikost a tvar a jejich kombinace na umělých květech vytištěných na 3D tiskárně. Zjistili jsme, že nejdůležitějším květním znakem byla barva následovaná velikostí a že efekt barvy byl zesílen efektem velikosti, ale pouze u preferované barvy. To naznačuje, že preference pro květinové vlastnosti jsou nějakým způsobem strukturované. Vliv symetrie jsme nenašli. Následně jsme v terénu pozorovali nenaivní pestřenky a čmeláky na jednodruhové patchi rostliny čertkusu lučního (Succisa pratensis). Zajímala nás role ostatních květních znaků v momentě, kdy se barva a velikost neliší. Nejdůležitějšími charakteristikami potom byla výška a efektivní počet kvítků v květenství. Pestřenky měly obecně delší návštěvy než čmeláci a navštěvovaly více květů. Na druhou stranu čmeláci dělali kratší a efektivnější návštěvy, což pravděpodobně souvisí s jejich eusocialitou. Klíčová slova: Syrphidae, Apidae, Eristalis tenax, Bombus spp., symetrie květu, velikost květu, barva květu, opylováníThe attractiveness of flowers to pollinators is mediated by several floral traits. The ability to discriminate the flowers based on these floral traits is crucial for the flower reproduction and pollinator nutrition and reproduction. We tested three floral traits - colour, size and shape - along with their combinations using artificially 3D printed flowers on model organism Eristalis tenax in laboratory conditions. Our findings revealed that the most important floral trait was the colour followed by size. Additionally, the effect of colour was enhanced by size, but only for the preferred colour. This suggests that preferences for specific floral traits can be structured. The effect of symmetry was not significant. Subsequently, we observed non-naïve hoverflies and bumblebees in the field on flower patch consisting of devil's-bit scabious (Succisa pratensis). We were interested in the role of other floral traits when the colour and size were indistinguishable. The most important characteristics were height and effective number of florets in the inflorescence. The hoverflies tend to do longer visits than bumblebees and visited more flowers as well. Conversely, bumblebees did shorter but more efficient visits, likely due to their eusociality. Keywords: Syrphidae, Apidae, Eristalis tenax, Bombus spp.,...Katedra zoologieDepartment of ZoologyPřírodovědecká fakultaFaculty of Scienc

Documentation of Urn Graves of Knovíz Culture by RPAS

This paper deals with the documentation, positional determination of urn graves of the Knovíz culture (1200 - 1000 BC), and geometric and positional determination of tumulus at the archaeological site located near the village Ctiněves, in the Usti region in the Czech Republic. Several hundred urn graves are located in the archaeological site and it is one of the biggest burial sites of Knovíz culture in the Czech Republic. RPAS (Remotely Piloted Aircraft System) was used for the documentation and positional determination of urn graves and tumulus. RPAS was equipped by visible spectral range, two near-infrared range, multispectral and thermal camera (one camera for a single flight). The result is a unique data set documenting this archaeological site. Thanks to the suitable winter and spring conditions in 2016 urn graves and tumulus could be detected on the basis of vegetation symptoms. The paper is also focused on how to process the data and creation of a differential digital surface model.</p

AUTOMATIC CLASSIFICATION OF POINT CLOUDS FOR HIGHWAY DOCUMENTATION

Mobile laser scanning systems confirmed the capability for detailed roadway documentation. Hand in hand with enormous datasets acquired by these systems is the increase in the demands on the fast and effective processing of these datasets. The crucial part of the roadway datasets processing, as well as in many other applications, is the extraction of objects of interest from point clouds. In this work, an approach to the rough classification of mobile laser scanning data based on raster image processing techniques is presented. The developed method offers a solution for a computationally low demanding classification of the highway environment. The aim of this method is to provide a background for the easier use of more sophisticated algorithms and a specific analysis. The method is evaluated using different metrics on a 1.8km long dataset obtained by LYNX Mobile Mapper over a highway

HISTORICAL PLASTER COMPOSITION DETECTION USING REFLECTANCE SPECTROSCOPY

Reflectance spectroscopy is a non-invasive method that is based on the fact that a specific object/material provides various reflectances in different wavelengths across the spectral range. It can provide unique information regarding the material composition of the object of interest and has been used in many fields in recent years. Determining composition of historical plaster is very important when defining its individual components and possibly place of origin or even its age. This information can be a key issue for its future repairs that are desired to be done as similar to the original method as possible. For a precise reflectance spectroscopy material detection, a fine spectral library is needed. Special mathematical methods are used for comparison of measured spectral curve with individual spectral curves stored in the used spectral library. The spectral analysis then shows similarity of the measured curve with the reference ones. This paper introduces results of the new plaster composition spectral library created by Department of Geomatics, Faculty of Civil Engineering, Czech Technical University in Prague within the Czech Ministry of Culture Project (DF13P01OVV002). This spectral library has been tested on two historical plaster samples

Temperature-dependent twist of double-stranded RNA probed by magnetic tweezer experiments and molecular dynamics simulations

RNA plays critical roles in the transmission and regulation of genetic information and is increasingly used in biomedical and biotechnological applications. Functional RNAs contain extended double-stranded regions, and the structure of double-stranded RNA (dsRNA) has been revealed at high resolution. However, the dependence of the properties of the RNA double helix on environmental effects, notably temperature, is still poorly understood. Here, we use single-molecule magnetic tweezer measurements to determine the dependence of the dsRNA twist on temperature. We find that dsRNA unwinds with increasing temperature, even more than DNA, with ΔTwRNA = −14.4 ± 0.7°/(°C·kbp), compared to ΔTwDNA = −11.0 ± 1.2°/(°C·kbp). All-atom molecular dynamics (MD) simulations using a range of nucleic acid force fields, ion parameters, and water models correctly predict that dsRNA unwinds with rising temperature but significantly underestimate the magnitude of the effect. These MD data, together with additional MD simulations involving DNA and DNA–RNA hybrid duplexes, reveal a linear correlation between the twist temperature decrease and the helical rise, in line with DNA but at variance with RNA experimental data. We speculate that this discrepancy might be caused by some unknown bias in the RNA force fields tested or by as yet undiscovered transient alternative structures in the RNA duplex. Our results provide a baseline to model more complex RNA assemblies and to test and develop new parametrizations for RNA simulations. They may also inspire physical models of the temperature-dependent dsRNA structure

COMPLEX ANALYSIS AND DOCUMENTATION OF HISTORICAL BUILDINGS USING NEW GEOMATIC METHODS

Documentation of a historical building is very important process preceding to every restoration or reconstruction work. It helps to preserve even minor information about objects shape, state, position and is often used for work advancement planning. Documentation is usually done using precise 3D model creation from which demanded cuts like ground plan are created. This papers shows how new geomatics methods can be used for 3D model creation and its placement in the area, that can be very interesting in terms of north-south position. As a case study two historical churches located in Czech Republic (towns of Holubice and Kralovice) has been used. Photogrammetry and laser scanning methods for 3D model creation are introduced