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192. Bezobratlí - jejich výuka a výzkum na Univerzitě Karlově v Praze
- Creator:
- Jan Buchar
- Format:
- print, bez média, and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, Univerzita Karlova., Katedra systematické zoologie, 19.-21. století, bezobratlí, studium a výuka, přírodovědný výzkum, zoologové, invertebrates, study and teaching, natural science research, zoologists, čeští zoologové, czech zoologists, 2, and 57/59
- Language:
- Czech
- Description:
- Jan Buchar.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
193. Bezobratlí na katedře ekologie Přírodovědecké fakulty Univerzity Karlovy v Praze
- Creator:
- Jan Fott
- Format:
- print, bez média, and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, Univerzita Karlova., Katedra ekologie, ekologie, přírodovědný výzkum, bezobratlí, ecology, natural science research, invertebrates, univerzitní výzkum, university research, 2, and 57/59
- Language:
- Czech
- Description:
- Jan Fott.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
194. Bi-directional acclimation of Cycas micronesica leaves to abrupt changes in incident light in understory and open habitats
- Creator:
- Marler, T. E.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- dynamická fotosyntéza listů, kolísající světlo, fenotypová plasticita, fotosyntetická indukce, cykad, dynamic leaf photosynthesis, fluctuating light, phenotypic plasticity, photosynthetic induction, 2, and 581
- Language:
- Multiple languages
- Description:
- Leaf gas-exchange responses to shadefleck-sunfleck and sun-cloud transitions were determined for in situ Cycas micronesica K.D. Hill plants on the island of Guam to add cycads to the published gymnosperm data. Sequential sunfleck-shadefleck transitions indicated understory leaves primed rapidly but open field leaves primed slowly. Time needed to reach 90% induction of net CO2 assimilation (PN) was 2.9 min for understory leaves and 13.9 min for open field leaves. Leaf responses to sun-cloud transitions exhibited minimal adjustment of stomatal conductance, so PN rapidly returned to precloud values following cloud-sun transitions. Results indicate bi-directional leaf acclimation behavior enables mature C. micronesica trees to thrive in deep understory conditions in some habitats and as emergent canopy trees in other habitats. These data are the first nonconifer gymnosperm data; the speed of gas-exchange responses to rapid light transitions was similar to some of the most rapid angiosperm species described in the literature., T. E. Marler., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
195. Bioaccumulation and photosynthetic activity response of sweet sorghum seedling (Sorghum bicolor L. Moench) to cadmium stress
- Creator:
- Xue, Z. C., Li, J. H., Li, D. S., Li, S. Z., Jiang, C. D., Liu, L. A., Wang, S. Y., and Kang, W. J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, spectral reflectance, soil contamination, chlorophyll a fluorescence, energy plant, photosynthetic activity, 2, and 581
- Language:
- Multiple languages
- Description:
- A hydroponic experiment was conducted to investigate bioaccumulation and photosynthetic activity response to Cd in sweet sorghum seedlings. The seedlings were treated with 0, 50, and 100 μM Cd for 15 d. Our results showed that morphological characteristics of sweet sorghum were significantly affected by Cd treatments. The Cd concentrations in roots and shoots increased with increasing Cd concentrations in the nutrition solution; higher Cd accumulation was observed in the roots. Meanwhile, the photosynthetic activity decreased significantly and a shape of chlorophyll (Chl) a fluorescence transient in leaves was altered by Cd treatments. The Chl contents in the leaves decreased significantly, which was demonstrated by a change of spectral reflectance. Our data indicated that the higher Cd concentration reduced Chl contents and inhibited electron transport in the leaves, leading to the decrease of photosynthetic activity., Z. C. Xue, J. H. Li, D. S. Li, S. Z. Li, C. D. Jiang, L. A. Liu, S. Y. Wang, W. J. Kang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
196. Biodiversity - economy or ecology? Long-term study of changes in the biodiversity of aphids living in steppe-like grasslands in Central Europe
- Creator:
- Osiadacz, Barbara, Hałaj, Roman, and Chmura, Damian
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polokřídlí, Hemiptera, Aphidoidea, bio-ecological groups, community structure, protected habitats, loss of biodiversity, human impact, NMDS methods, regional hotspots, 2, and 59
- Language:
- English
- Description:
- This paper examines the changes in the species composition of aphids living in dry calcareous grasslands in Central Europe over a 25-year period. To the best of our knowledge, this is the first analysis of this type in the world that takes into account both previous and current data on species richness as well as groups of aphids that are distinguishable on the basis of biological and ecological criteria such as host-alternation and feeding types, life cycle, ecological niche, symbiosis with ants and their ecological functional groups. Over the period of more than 25 years, there has been a significant decrease in aphid α-diversity, from 171 to 105 species. The gain, which is in species not previously recorded, was 17 taxa. The loss of biodiversity occurred despite the fact that these habitats are protected and are valuable regional biodiversity hotspots. The losses are mostly related to intensive human activity in adjacent areas, which, unfortunately, has resulted in the isolation of these small, protected environmental islands by the removal of ecological corridors. Since, as is shown in this study, the frequencies between individual biological and ecological groups of aphids have been retained, it would be possible to restrict this loss of biodiversity if appropriate actions are taken., Barbara Osiadacz, Roman Hałaj, Damian Chmura., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
197. Biodiverzita - napřed poznat, až pak chránit: Historické příčiny druhové rozmanitosti v regionu Dokeska
- Creator:
- Jiří Sádlo
- Type:
- article, články, model:article, and TEXT
- Subject:
- Obecná ekologie, biodiverzita, ochrana přírody, biodiversity, nature conservation, Máchovo jezero (Česko : oblast), Máchovo jezero Region (Czechia), 2, and 574
- Language:
- Czech
- Description:
- In this issue, we bring you an essay on the International Year of Biodiversity, a year-long celebration of biological diversity and its value for life on Earth, taking place around the world during 2010. This observance is intended, through activities and events in many countries, to help raise awareness of the importance of biodiversity. and Jiří Sádlo.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
198. Biogeografie a šíření kudlanky nábožné v Evropě
- Creator:
- Vitáček, Jakub and Janšta, Petr
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biologické vědy, biogeografie, kudlanky, biogeography, Mantodea, Evropa, Europe, kudlanka nábožná, Praying Mantis, Mantis religiosa, 2, and 57/59
- Language:
- Czech
- Description:
- Kudlanka nábožná (Mantis religiosa) je příklad teplomilného druhu, který v posledních letech začal expandovat i do severnějších oblastí Evropy. Na základě studia mitochondriálních markerů se ukázalo, že v rámci Evropy kudlanky náleží do tří odlišných genetických linií. Tyto linie (západoevropská, středoevropská a východoevropská) se postupně po poslední době ledové šířily na sever z různých glaciálních refugií. Tuto teorii také podporují paleoklimatická data a distribuční modely možného šíření kudlanek po poslední době ledové., The Praying Mantis (Mantis religiosa) is an example of a thermophilic species, which has recently been expanding northwards across Europe. Based on the study of mitochondrial genes, it has been shown, that the European M. religiosa belong to three different genetic lineages (West-, Central- and East-European). These lineages have been gradually spreading northwards from different glacial refugias after the last glacial period. This theory has also been supported using paleoclimatic data and distribution models of the potential spread of M. religiosa after the last glacial period., and Jakub Vitáček, Petr Janšta.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
199. Biogeography of tenebrionid beetles (Coleoptera: Tenebrionidae) in the circum-Sicilian islands (Italy, Sicily): Multiple biogeographical patterns require multiple explanations
- Creator:
- Fattorini, Simone
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Sicílie (Itálie), Středozemní moře (oblast), Sicily (Italy), Mediterranean area, biogeography, Coleoptera, Tenebrionidae, Pleistocene, species-area relationship, 2, and 59
- Language:
- English
- Description:
- The tenebrionid beetles on 25 circum-Sicilian islands were studied to determine the influence of island geographical and landscape features on three main intercorrelated biogeographical patterns: (1) species richness, studied using species-area and species environment relationships, (2) species assemblage composition, investigated using Canonical Correspondence Analysis (CCA), and (3) inter-site faunal similarity, investigated using Canonical Correlation Analysis (CANCOR) applied to multidimensional scaling of inter-island faunal dissimilarities. Species richness was mostly influenced by island area and landscape heterogeneity (expressed using various indices of diversity based on land cover categories). When species identities were considered in the CCA, no substantial effect of landscape was detected. Current island isolation did not have a strong influence on species richness, but has a distinct effect in determining species assortments on the remotest islands. Historical influences of Pleistocene landbridge connections were not detectable in species richness relationships using geographical variables in species richness analyses or in assemblage gradients in the CCA, but emerged distinctly from inter-island similarities in the CANCOR. and Simone Fattorini.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
200. Bioinformatics analysis on structural features of microRNA precursors in insects
- Creator:
- Li, Jisheng, Fan, Wei, You, Zhengying, and Zhong, Boxiong
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, structural features, bioinformatics, insects, microRNA precursors, 2, and 59
- Language:
- English
- Description:
- To date, thousands of microRNAs (miRNAs) and their precursors (pre-miRNAs) have been identified in insects and their nucleotide sequences deposited in the miRBase database. In the present work, we have systematically analyzed, utilizing bioinformatics tools, the featural differences between human and insect pre-miRNAs, as well as differences across 24 insect species. Results showed that the nucleotide composition, sequence length, nucleotides preference and secondary structure features between human and insects were different. Subsequently, with the aid of three available SVM-based prediction programs, pre-miRNA sequences were evaluated and given corresponding scores. Thus it was found that of 2633 sequences from the 24 chosen insect species, 2229 (84.7%) were successfully recognized by the Mirident classifier, higher than Triplet-SVM (72.5%) and PMirP (72.6%). In contrast, four species, including the domesticated silkworm, Bombyx mori L., the fruit fly, Drosophila melanogaster Meigen, the honeybee, Apis mellifera L. and the red flour beetle, Tribolium castaneum (Herbst), were found to be largely responsible for the poor performance of some sequence matching. Compared with other species, B. mori especially showed the worst performance with the lowest average MFE index (0.73). Collectively these results pave the way for understanding specificity and diversity of miRNA precursors in insects, and lay the foundation for the further development of more suitable algorisms for insects., Li, Jisheng ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public