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832. Stopy retrovirů v lidském genomu

Creator:
Famfulíková, Mirka and Jan Pačes
Format:
bez média and svazek
Type:
article, text, články, journal articles, model:article, and TEXT
Subject:
Biologické vědy, biologie, retroviry, RNA viry, lidský genom, genetická transkripce, biology, retroviruses, RNA viruses, human genome, genetic transcription, endogenní retrovirové elementy, human endogenous retroviruses, HERV, 2, and 57/59
Language:
Czech
Description:
Retroviry jsou RNA viry, které se replikují v hostitelské buňce. Využívají enzymu reverzní transkriptázy, která přepisuje jejich RNA do DNA. Tato DNA je pak enzymem integrázou začleňována do hostitelského genomu. Pokud dojde k integraci retroviru v germinální linii, může se tento retrovirus stát součástí lidského genomu. V lidském genomu tyto retrovirové elementy (Human Endogenous Retroviruses = HERVs) tvoří až 8 % DNA. Donedávna se vědci domnívali, že HERVy jsou neaktivní, tzn. neinfikují další buňky. Během evoluce byly mnohokrát mutovány a pozbyly schopnosti genové exprese. Převažoval také názor, že HERVy nejsou ani trankribovány - nejsou přepisovány do mRNA. Ze současných výzkumů však vyplývá, že HERVy jsou hojně přepisovány v mnoha různých tkáních lidského těla. Někdy mohou z této mRNA dokonce vznikat krátké peptidy, které pak mohou buňku ovlivňovat. Jak rozsáhlý je význam transkripce, je nyní předmětem dalších zkoumání., A retrovirus is an RNA virus using its own reverse transcriptase and integrase to produce DNA from its genome and incorporate it into the host’s genome. When a retrovirus is integrated in a germ line, it can become a part of the host genome. In human genome these elements occupy about 8 % of DNA and are called human endogenous retroviruses (HERVs). During evolution they mutated and lost their function to infect other cells. They were considered inactive (not expressed), however, transcription of HERVs in many different tissues in most human cells has recently been proved., and Mirka Famfulíková, Jan Pačes.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

833. Stopy sjezdového lyžování v půdě

Creator:
Miroslav Zeidler, Marek Banaš, Radim Hédl, and Houška, Jakub
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Obecná ekologie, ekologie, horské ekosystémy, půda, sjezdové lyžování, ecology, mountain ecosystems, soil, downhill skiing, Hrubý Jeseník (Česko : pohoří), Hrubý Jeseník Mountains (Czechia), 2, and 574
Language:
Czech
Description:
Miroslav Zeidler, Marek Banaš, Radim Hédl, Jakub Houška.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

834. Středomořská kobylka v Praze na Karlově náměstí

Creator:
Pavel Pecina
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Životní prostředí a jeho ochrana, životní prostředí, hmyz, kobylky, environment, insects, Tettigonioidea, 2, and 502
Language:
Czech
Description:
Článek vychází z pozorování výskytu kobylky malé (Phaneroptera nana) v centru Prahy. Představuje blíže tento druh, jeho rozšíření, prazskou mikropopulaci a poznatky z chovu v insektáriu., This article is based on observations of the Mediterranean Katydid (Phaneroptera nana) in the centre of Prague. It presents the species, its spread, its Prague micropopulation and information on insectarium breeding in some detail., and Pavel Pecina.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

835. Střevlík uherský - jeho biologie, početnost, ochrana a péče o lokality

Creator:
Lukáš Čížek, Pokluda, Pavel, Kubáň, Vítězslav, Hauck, David, and Elek, Zoltán
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, hmyz, střevlíkovití, ekologie, zoology, insects, ground beetles, ecology, Morava jižní (Česko), Moravia, Southern (Czechia), 2, and 59
Language:
Czech
Description:
Střevlík uherský (Carabus hugaricus hungaricus) je druhem dlouhostébelných panonských stepí. Patří mezi zvláště chráněné brouky a je rovněž druhem evropsky významným. V České republice přežívá už pouze na Pouzdřanské stepi a na Pálavě. V článku shrnujeme výsledky výzkumů jeho stanovištních preferencí, demografie a mobility, diskutujeme možnosti jeho ochrany a zároveň se dotýkáme bolestivého tématu ochranářské péče o lokality tohoto druhu., The Carabus hungaricus ground beetle is a highly endangered, dry-grassland specialist listed in the EU Habitats Directive. In the Czech Republic, the beetle survives on the last two sites including the Pouzdřany steppe, and the Pálava hills. Here we report results of extensive mark-recapture studies of this species, including its habitat preference, demography, and dispersal abilities. Furthermore, we discuss the options for its conservation and conservation management of the two inhabited sites., Lukáš Čížek ... [et al.]., and Pokračování čl. na str. CXV kuléru Živy 5/2014
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

836. Střevlík uherský - jeho biologie, početnost, ochrana a péče o lokality: (pokračování článku ze str. 222-225 této Živy)

Creator:
Lukáš Čížek, Pokluda, Pavel, Kubáň, Vítězslav, Hauck, David, and Elek, Zoltán
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, entomologie, střevlíkovití, entomology, ground beetles, Morava jižní (Česko), 2, and 59
Language:
Czech
Description:
Lukáš Čížek ... [et al.]. and Pokračování čl. ze str. 222-225 Živy 5/2014
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

837. Structure of scuttle fly communities (Diptera: Phoridae) in two habitats on a Mediterranean mountain

Creator:
García-Romera, Carlos and Barrientos, José A.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, dvoukřídlí, Diptera, Phoridae, diversity, Montseny, beech forest, scrubland, 2, and 59
Language:
English
Description:
Phoridae (scuttle flies) are widely distributed, occur in many types of habitats and are ecologically versatile, which makes them an excellent bioindicator group for evaluating faunal diversity. The structure of scuttle fly communities was compared in two Mediterranean habitats in the Montseny Natural Park (Catalonia, Spain) that differ in vegetation and microclimate: beech forest and highland scrubland. 3684 male individuals belonging to 135 species of scuttle flies were identified. Scuttle flies were more abundant in beech forest than scrubland. Observed and estimated species richness were lower in scrubland than in beech forest, while diversity was similar in both habitats. Community evenness was greater in scrubland than beech forest. Therefore, the percentage of dominant and subdominant species was higher in scrubland than beech forest, while the percentage of rare species was higher in beech forest than scrubland. Scuttle fly species composition was significantly different in the two habitats, but it was similar among plots within the same habitat. Megaselia pectoralis (Wood, 1910) and Megaselia subpleuralis (Wood, 1909) were the dominant species in beech forest, while Megaselia pusilla (Meigen, 1830), Megaselia pumila (Meigen, 1830), Megaselia superciliata (Wood, 1910) and Megaselia diversa (Wood, 1909) were the dominant species in scrubland. Trophic specialization was higher in beech forest than scrubland. Saprophages were the dominant trophic group in beech forest, while fungivores and polyphages were dominant in scrubland. The high biodiversity of scuttle flies recorded in the Montseny Natural Park indicates that there is also a high diversity of other taxa there and that these Mediterranean mountains are of high conservation status., Carlos García-Romera, José A. Barrientos., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

838. Substrát, půda, vegetace a měkkýši. 1. Ekologie evropských měkkýšů ve světle současných poznatků

Creator:
Vojen Ložek
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Životní prostředí a jeho ochrana, vegetace, půda, měkkýši, ekologie, 2, and 502
Language:
Czech
Description:
Fossil continental molluscs have not hitherto been regarded as reliable paleoenvironmental indicators. Little was known about their ecological requirements or their position in characteristic biomes of the Quaternary climatic cycle, for instance in the loess steppe. Only recent analyses of their assemblages in a broad environmental context have shown that they are indicative of a number of important environmental phenomena in the same way as pollen grains or vertebrate remains. and Vojen Ložek.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

839. Substrát, půda, vegetace a měkkýši. 2. Svědectví měkkýšů o historii naší přírody a krajiny

Creator:
Vojen Ložek
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, půda, vegetace, měkkýši, příroda, krajina, 2, and 59
Language:
Czech
Description:
Fossil molluscan successions from ca 450 sites provide evidence of the paleo-environmental history of the Czech Republic and Slovakia during the Quaternary. They not only reflect the Quaternary cycle of warm and cold phases but also a number of various events, such as the impact of the cold oscillation at 8,2 ky BP or the detailed reconstruction in time and space of the habitat patchwork in areas where other fossils are sparse or absent, particularly in karstlands, in the full scale of elevations. and Vojen Ložek.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

840. Succession in ant communities (Hymenoptera: Formicidae) in deciduous forest clear-cuts - an Eastern European case study

Creator:
Tăuşan, Ioan, Dauber, Jens, Trică, Maria R., and Markó, Bálint
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, blanokřídlí, mravencovití, opadavé lesy, Hymenoptera, ants, deciduous forests, Formicidae, secondary succession, clear-cutting, community structure, pitfall traps, 2, and 59
Language:
English
Description:
Clear-cutting, the main method of harvesting in many forests in the world, causes a series of dramatic environmental changes to the forest habitat and removes habitat resources for arboreal and epigeal species. It results in considerable changes in the composition of both plant and animal communities. Ants have many critical roles in the maintenance and functioning of forest ecosystems. Therefore, the response of ants to clear-cutting and the time it takes for an ant community to recover after clear-cutting are important indicators of the effect of this harvesting technique on the forest ecosystem. We investigated ground-dwelling ant communities during secondary succession of deciduous forests in Transylvania, Romania. Using space-for-time substitution, we explored a chronosequence from clear-cuts to mature forests (> 120 years). The object was to determine if cutting has measurable effects on ant community structure, and if ant species richness differs between successional stages. We recorded a total of 24 species of ants, 11 characteristic of forests and seven of open landscape. Ant species richness was higher in clear-cuts compared to closed-canopy and old stands. Number of ant individuals was highest in young age classes and lowest in closed-canopy age classes. There was no drastic change in species richness during the succession, however differences in community composition at different stages were recorded. Open landscape species are able to rapidly colonize following disturbance but disappear when the forest sites mature and many forest ant species are capable of surviving clear cutting., Ioan Tăuşan, Jens Dauber, Maria R. Trică, Bálint Markó., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public