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Hlinka D.,Prague Fertility Center | Lazarovska S.,Prague Fertility Center | Rutarova J.,Ustav pro Peci o Matku a Dite | Pichlerova M.,Prague Fertility Center | And 2 more authors.
Ceska Gynekologie | Year: 2012

Objective: The evaluation of the developmental abilities of human embryos according to the timing of their early mitotic cleavages. Design: Retrospective study. Setting: Prague Fertility Centre and Institute for Care of Mother and Child, CAR, Prague. Methods: The embryos obtained in IVF program were used for further observations and subjected to automated time-lapse monitoring (PrimoVision, Cryo-Innovation, 1 picture/10 min, intermittent whitelight illumination) under standard cultivation conditions (37.0 °C , 5% CO 2 in humid air). Image sequences were digitally recorded for later use. For intravital spindle detection we used polaryzing microscopy (Oosight, Research Instruments) and Hoechst 33342 fluorescent dye for intravital chromatin visualization. A total number of 180 human embryos which gave a vital pregnancies (FHB, fetal heart beat) were analysed retrospectively for timing of early cleavages. In our study, the exact timing of the four interphases (IP) and synchrony of sister cell divisions (ID, interval division) occurring after fertilization were identified and manually recorded. Interphases: IP1 was defined as the period from fertilization till 2 cell stage. IP2 between 2 and 3 cells stages, IP3 between 3 and 5 and IP4 between 5 and 9 cells embryo. Interval division: ID2 was recorded as a time interval between 3 and 4 cells, ID3 between 5 and 8 cells and ID4 between 9 and 16 cells stage embryos. Results: In the embryos giving viable pregnancies, the durations of IP1 was 20-26 hrs. IP2 was 10-12 hrs, IP3 was 14-16 hrs and IP4 was 20-26 hrs. In these embryos, the sister blastomeres cleaved in a very synchronous manner. The duration of ID1 was recorded to varry from 120 to 210 min. ID2 from 20 to 60 min., ID3 from 120 to 240 min. and ID4 from 230 to 360 min. Conclusion: The viable embryos cleave in a very similar time pattern which can be defined and applied as referencial value. Non-invasive monitoring of the timing of early embryo cleavages can be used as an objectively measurable predictor of human embryo. Source


Durna E.,Center for Lifelong Learning | Kimakova K.,Institute of Biology and Ecology | Romanova L.,Center for Lifelong Learning | Sekerak J.,Center for Lifelong Learning | Sveda D.,Institute of Mathematics
ICETA 2012 - 10th IEEE International Conference on Emerging eLearning Technologies and Applications, Proceedings | Year: 2012

This article elaborates strategy of modernization and innovation of learning at Faculty of science (further on as FS) at Pavol Jozef Šafárik University in cooperation with Centre for innovative learning, which was founded within the framework of Modern and interactive learning project at P.J. Šafárik University in Košice. In the process of writing this article the authors used practical experiences gained by working in the Centre for innovative learning and by taking part in Modernization of educational process on primary and secondary schools national projects. They contemplate about possibilities of more effective introduction of modernization and innovation elements based on digital technologies into educational process with professional assistance. The article states specific example. © 2012 IEEE. Source


Salek M.,Academy of Sciences of the Czech Republic | Chrenkova M.,University of South Bohemia | Dobry M.,Institute of Biology and Ecology | Kipson M.,Academy of Sciences of the Czech Republic | And 3 more authors.
Agriculture, Ecosystems and Environment | Year: 2016

During the last half of century, agricultural intensification within European farmlands caused the deprivation of farmland biodiversity, including farmland birds. Since then different conservation measures have been introduced to reverse declining trends of these birds. Yet, variable success of these measures suggests that habitat management requires planning at appropriate spatial scales. In this study, we examine habitat associations of the Little Owl, a rapidly declining farmland bird, within the context of Central European farmland. We collected presence/absence data from three different countries (the Czech Republic, Slovakia and Hungary) and examined habitat associations within and between regions at three different spatial scales: nest site, home range and landscape. We show that certain habitat associations are shared across all study regions, namely those involving grasslands and farm buildings that are used for foraging and nesting, respectively. Inter-regional analysis reveals that grasslands, gardens/orchards and farm buildings are most important habitats at small spatial scales, whereas at large spatial scales, the owl is positively associated with open habitats in terms of arable fields. We suggest that conservation planning should take into account both regional and inter-regional aspects of a species' habitat associations to distinguish between common habitat requirements and local species-environment relationships. © 2016 Elsevier B.V. Source


Dominguez J.,University of Vigo | Aira M.,University of Vigo | Breinholt J.W.,University of Florida | Stojanovic M.,Institute of Biology and Ecology | And 4 more authors.
Molecular Phylogenetics and Evolution | Year: 2015

Earthworms belonging to the family Lumbricidae are extremely abundant in terrestrial temperate regions. They affect soil properties and nutrient cycling, thus shaping plant community composition and aboveground food webs. Some lumbricids are also model organisms in ecology and toxicology. Despite the intense research efforts dedicated to lumbricids over the last 130. years, the evolutionary relationships and taxonomic classification of these organisms are still subject to great debate. Resolution of their systematics is hampered by the structural simplicity of the earthworm body plan and the existence of cryptic species. We sampled 160 earthworm specimens belonging to 84 lumbricid species (28 genera) and 22 Lumbricoidea outgroups, sequenced two nuclear genes, four mitochondrial genes and seven mitochondrial tRNAs and examined 22 morphological characters. We then applied a combination of phylogenetic methods to generate the first robust genus-level phylogeny of the Lumbricidae. Our results show that the current Lumbricidae classification and the underlying hypotheses of character evolution must be revised. Our chronogram suggests that lumbricids emerged in the Lower Cretaceous in the holarctic region and that their diversification has been driven by tectonic processes (e.g. Laurasia split) and geographical isolation. Our chronogram and character reconstruction analysis reveal that spermathecae number does not follow a gradual pattern of reduction and that parthenogenesis arose from sexual relatives multiple times in the group; the same analysis also indicates that both epigeic and anecic earthworms evolved from endogeic ancestors. These findings emphasize the strong and multiple changes to which morphological and ecological characters are subjected, challenging the hypothesis of character stasis in Lumbricidae. © 2014 Elsevier Inc. Source


Kovacik J.,Institute of Biology and Ecology | Klejdus B.,Mendel University in Brno | Hedbavny J.,Mendel University in Brno | Backor M.,Institute of Biology and Ecology
Plant Science | Year: 2010

Species of the genus Scenedesmus are frequently used in studies focused on heavy metal toxicity and phenols represent important tool for stress protection. However, deeper knowledge about accumulation of phenolic metabolites in algae still absents. We therefore studied selected metabolic responses of widely distributed green algal species Scenedesmus quadricauda to short-term (24 h) effect of copper (Cu), salicylic acid (SA) and their combined application (25 μM for both). Exposure to Cu led to decrease in chlorophylls while SA stimulated increase in chlorophylls. Soluble proteins and total soluble phenols were depressed by Cu treatment while SA had no effect and did not reverse influence of Cu in combined variant. Endogenous SA decreased in Cu + SA treatment and this depletion had no direct effect on the accumulation of the majority of detected phenolic acids, while individual amino acids seemed to be affected. Considerable accumulation of benzoic acids and their noticeable responses to SA may suggest involvement in protection against Cu toxicity since intracellular Cu remained unchanged by exposure to Cu + SA. These observations are discussed in the context of biosynthesis of phenols and possible signalling mechanisms are also suggested. © 2010 Elsevier Ireland Ltd. All rights reserved. Source

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