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Start Over Coverage 262-266

1. Fyzikální a přírodovědné soutěže pro talentované žáky v České republice a na Slovensku

Creator:
Kříž, Jan and Konrád, Ľubomír
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fyzika, fyzikální soutěže, physics competitions, learners, Česko, Slovensko, Czechia, Slovakia (Czechoslovakia), soutěže přírodovědné, 6, and 53
Language:
Czech
Description:
Jan Kříž, Lubomír Konrád. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Occurrence, prevalence, and effects of the myxozoan Tetracapsula bryozoides parasitic in the freshwater bryozoan Cristatella mucedo (Bryozoa: Phylactolaemata)

Creator:
Okamura, Beth
Format:
print
Type:
model:internalpart and TEXT
Subject:
Myxozoa, Bryozoa, prevalence, and pathogenicity
Language:
English
Description:
During an ecological investigation of populations of the freshwater bryozoan, Cristatella mucedo Cuvier, parasitic sac-like stages of the myxozoan, Tetracapsula bryozoides Canning, Okamura et Curry, 1996 were discovered within the body cavity of some bryozoan colonies. Subsequent to their detection, data were collected on the incidence and prevalence of myxo-zoans in bryozoan populations in the Thames Valley region and on the effects of myxozoans on their hosts. Notable spatial and temporal variation in incidence and prevalence of myxozoans was documented. The production of statoblasts by bryozoans was significantly compromised by myxozoan infection although the production of larvae was not. Infection by myxozoans resulted in generalized swelling, malformation, degeneration, and slower response times in bryozoan colonies. These findings indicate that myxozoans adversely affect host fitness and may therefore influence population levels. Light microscopy revealed that multiple myxozoan sacs can be present within the continuous body cavity of bryozoan colonies and that sacs apparently undergo fission. Infective spores that develop within sacs are at least on some occasions released into the body cavity of bryozoans. Nothing is known of the subsequent stages in the life cycle of this myxozoan, including whether T. bryozoides infects another species. Spores may be released into the water column to infect new hosts or they may be introduced to new hosts when infected bryozoans are ingested.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Uplatnění spektroskopických metod při zkoumání autenticity historických rukopisů

Creator:
Nesměrák, Karel
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
spektroskopie, rukopisy, spectroscopy, manuscripts, 6, and 53
Language:
Czech
Description:
Pozměňování či falzifikace psaných textů jsou bezesporu staré jako sám vynález písma. Důvody pro takové jednání byly různé, nicméně skutečné stáří, respektive autenticita, daného rukopisu mají velký dopad na jeho význam, ať již pro historii, nebo - v případě současných rukopisů - z hlediska právního. U některých historických rukopisů je otázka jejich datování řešena s použitím spektroskopických technik, jejichž hlavní výhodou je nedestruktivnost nebo minimální invazivnost, neohrožující samu existenci zkoumaného dokumentu. V článku jsou zmíněny nejčastější spektroskopické metody používané k těmto účelům, včetně příkladů konkrétních studovaných rukopisů., The alteration or falsification of written texts is undoubtedly old as invention of scripture itself. The reasons for such behaviour are different, but the actual age or authenticity of the manuscript had a great impact on its signification, whether for history or, in the case of contemporary manuscripts, from a legal point of view. For historical manuscripts, the question of their dating is solved using spectroscopic techniques whose main advantage is non-destructiveness or minimal invasiveness, not endangering the very existence of the document under study. In the article the most frequent spectroscopic methods used for these purposes are mentioned and examples of particular studied manuscripts are given., Karel Nesměrák., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public