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1892. Chrpy - botanická noční můra?: o jejich diverzitě, systematice a hybridizaci

Creator:
Petr Koutecký
Format:
bez média and svazek
Type:
article, text, články, journal articles, model:article, and TEXT
Subject:
Biologické vědy, biologie, botanika, pěstitelství, fyziologie rostlin, botany, biology, horticultural education, plant physiology, hybridizace rostlin, polyploidie, chrpy, Centaurea, 2, and 57/59
Language:
Czech
Description:
Článek přestavuje taxonomicky problematický rod chrpa z čeledi Asteraceae. Jsou diskutovány současné pohledy na vymezení a vnitřní členění rodu založené na molekulárních znacích. Dále je popsána problematika hybridizace, která je v rodu velmi častá, a její souvislost s polyploidií (druhy stejné ploidie se často kříží za vzniku rozsáhlých a variabilních hybridních rojů, zatímco mezi ploidiemi je silná reprodukční bariéra)., Centaurea is a taxonomically critical genus from the Asteraceae family. Current delimitation of the genus and its internal classification based on molecular data are discussed. Hybridization and polyploidy are common in Centaurea. The frequency of hybridization depends on ploidy levels of the taxa (homoploid taxa usually hybridize easily and form extensive and variable hybrid swarms, while heteroploid taxa are reproductively strongly isolated)., and Petr Koutecký.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1893. Chrudimské kramářské tisky s fingovaným impresem

Creator:
Drozda, Martin
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Josef Jan Košina, Františka Košinová, Chrudim, broadside ballad sheets, false imprints, and 1st half of the 19th century
Language:
Czech
Description:
The Chrudim printing house was one of the most important producers of broadside ballad sheets in the 19th century. However, at the time of the printers Josef Jan Košina and his wife Františka, a significant part of the production did not contain information about printing in Chrudim. To hide the origin of broadside ballad sheets, the Chrudim printing house would at times falsify the place of printing. This study elucidates how to identify false imprints of broadside ballad sheets by comparing woodcuts and typographic decoration. Based on the collection of Moravian Library in Brno, the study shows that false imprints of broadside ballad sheets represent almost a third of the printing production in the Chrudim printing house. This finding poses a problem for research into the printing production of broadside ballad sheets in the first half of the 19th century because the use of the false imprints and missing information can greatly distort the extent of the entire production. This study also provides an analysis of the most commonly used false locations as well as the types of broadside ballad sheets produced by the Chrudim printing house. Last but not least, it seeks to outline the main reasons for the use of false imprints of broadside ballad sheets.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1894. Chyba odečítání hodnot svislých úhlů prostorových optických skenerů a její numerická kompenzace

Creator:
Brzobohatý, Jindřich and Pokorný, Petr
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
spatial optical scanners, calibration, optimization, prostorové optické skenery, kalibrace, and optimalizace
Language:
Czech
Description:
The paper presents an issue of determination of the vertical index error of spatial optical scanners. The procedure for numerical calibration is presented and the methodology is verified with experimental data. The proposed procedure is basically intended for numerical calibrations of measured point-cloud data, and also to improve the output quality and to eliminate costs of mechanical calibrations of optical scanners. and V práci je analyzována problematika určení velikosti chyby čtení svislého úhlu při měření prostorovými optickými skenery. Je představen postup jejího numerického určení a metodika je aplikována a ověřena na experimentálních datech. Navržený postup může sloužit k numerickým kalibracím měřených dat mračen bodů, výrazně zvýšit kvalitu výstupů, a také eliminovat náklady vybrané mechanické kalibrace optických skenerů.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1895. Chyby, neurčitosť a neistota merania v kocke

Creator:
Gutten, Miroslav, Michalík, Ján, and Kúdelčík, Jozef
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
elektrotechnika, chyby měření, electric engineering, measurement errors, 6, and 53
Language:
Czech
Description:
Meranie je súhrn činností s cieĺom určiť hodnotu meranej veličiny. Táto hodnota by sa mala uvádzať spolu s toleranciou, v ktorej leží pravá hodnota meranej veličiny, prípadne toĺkými číslami, koĺko odpovedá platným miestam výsledku merania. To je dôležité najmä v súčasnosti, keď sa pre spracovanie výsledkov používajú počítače pracujúce s číslami s veĺkým počtom miest. Žiadnym meraním nezískame správnu hodnotu meranej veličiny, pretože každé meranie je zaťažené chybou. Chyba charakterizuje presnosť merania. Účelom štúdia chýb je zistenie celkovej chyby, jej čiastkových zložiek a ich príčin. Analýza chýb je základnou podmienkou zvyšovania presnosti merania. Výsledok merania je neúplný, pokiaĺ neobsahuje možný rozsah chýb., Miroslav Gutten, Ján Michalík, Jozef Kúdelčík., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1900. Circadian molecular clocks tick along ontogenesis

Creator:
Alena Sumová, Zdeňka Bendová, Martin Sládek, El-Hennamy, R., Matějů, K., Lenka Polidarová, Serhiy Sosniyenko, and Helena Illnerová
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, neurofyziologie, cirkadiánní rytmy, ontogeneze, neurophysiology, circadian rhythms, ontogeny, suprachiasmatic nucleus, peripheral clock, clock gene, 14, and 612
Language:
English
Description:
The circadian system controls the timing of behavioral and physiological functions in most organisms studied. The review addresses the question of when and how the molecular clockwork underlying circadian oscillations within the central circadian clock in the suprachiasmatic nuclei of the hypothalamus (SCN) and the peripheral circadian clocks develops during ontogenesis. The current model of the molecular clockwork is summarized. The central SCN clock is viewed as a complex structure composed of a web of mutually synchronized individual oscillators. The importance of development of both the intracellular molecular clockwork as well as intercellular coupling for development of the formal properties of the circadian SCN clock is also highlighted. Recently, data has accumulated to demonstrate that synchronized molecular oscillations in the central and peripheral clocks develop gradually during ontogenesis and development extends into postnatal period. Synchronized molecular oscillations develop earlier in the SCN than in the peripheral clocks. A hypothesis is suggested that the immature clocks might be first driven by external entraining cues, and therefore, serve as “slave” oscillators. During ontogenesis, the clocks may gradually develop a complete set of molecular interlocked oscillations, i.e., the molecular clockwork, and become self-sustained clocks., A. Sumová, Z. Bendová, M. Sládek, R. El-Hennamy, K. Matějů, L. Polidarová, S. Sosniyenko, H. Illnerová., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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