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32. Diversity of adipokinetic hormones in termites (Isoptera)
- Creator:
- Jedličková, Veronika, Jedlička, Pavel, and Špuláková, Barbora
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, všekazi, Isoptera, termite, adipokinetic hormone, preprohormonal sequence, phylogenetic relationships, 2, and 59
- Language:
- English
- Description:
- In this study we report on the structural diversity of adipokinetic hormones (AKHs) in the evolutionarily oldest group of social insects, the termites (Isoptera). Using molecular methods combined with in silico bioinformatic analysis, we studied and compared the sequences coding for these neuropeptides in thirteen species of five families of Isoptera. There are three types of AKH octapeptides in termites: Empusa pennata adipokinetic hormone (Emppe-AKH; pQVNFTPNWamide), Microhodotermes viator corpus cardiacum peptide (Micvi-CC; pQINFTPNWamide) and Periplaneta americana cardioaccelerating hormone (Peram-CAH-I; pQVNFSPNWamide). Of these the Peram-CAH-I was the most frequently bioactive form detected in representatives of four out of the six families studied. The complete AKH preprohormones in the termites studied shared at least an 84% amino acid similarity. In agreement with current phylogenetic scenarios of termites as an internal monophyletic clade nested within cockroaches (Blattaria) in the proximity of the family Blattidae, our phylogenetic analysis of the AKH precursor sequences (in the absence of data for the Cryptocercidae) placed the Blattidae (Periplaneta americana) as a sister group of termites and the AKHs of other cockroach families (Blattellidae and Blaberidae) were more divergent from those of termites. Representatives of the basal termite families Mastotermitidae and Archotermopsidae (but also one rhinotermitid genus Prorhinotermes) occurred separately from the phylogenetically advanced lineage (Rhinotermitidae and Termitidae), and Neotermes (Kalotermitidae) was sister to all other termites included., Veronika Jedličková, Pavel Jedlička, Barbora Špuláková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33. Diversity of grasshoppers (Caelifera) recorded on the banks of a Ramsar listed temporary salt lake in Algeria
- Creator:
- Mahloul, Sarah, Harrat, Abboud, and Petit, Daniel
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brakická rostlinná společenstva, potravinové zdroje, halophytes, food sources, Alžírsko, Algeria, Caelifera, grasshopper, Dericorys, Calliptamus, temporary salt lake, dispersal, 2, and 59
- Language:
- English
- Description:
- The chotts in Algeria are temporary salt lakes recognized as important wintering sites of water birds but neglected in terms of the diversity of the insects living on their banks. Around a chott in the wetland complex in the high plains near Constantine (eastern Algeria), more than half of the species of plants are annuals that dry out in summer, a situation that prompted us to sample the vegetation in spring over a period of two years. Three zones were identified based on an analysis of the vegetation and measurements of the salt content of the soils. Surveys carried out at monthly intervals over the course of a year revealed temporal and spatial variations in biodiversity and abundance of grasshoppers. The inner zone is colonized by halophilic plants and only one grasshopper species (Dericorys millierei) occurs there throughout the year. Two polyphagous species of Calliptamus, which can feed on halophilic plants migrate from adjacent areas into the inner zone in August to feed on the plants growing there. The other species of grasshoppers remain in outer zones as they are unable to feed on halophilic plants. The greatest abundance of grasshoppers from August to winter was recorded in the inner zone and in spring and early summer in the outer zones. The dependence of D. millierei on bushes of Amaranthaceae and its moderate flight ability, features of the family Dericorytidae, limit this species ability to colonize neighbouring chotts., Sarah Mahloul, Abboud Harrat, Daniel Petit., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34. Do flower mixtures with high functional diversity enhance aphid predators in wildflower strips?
- Creator:
- Hatt, Séverin, Uyttenbroeck, Roel, Lopes, Thomas, Mouchon, Pierre, Chen, Julian, Piqueray, Julien, Monty, Arnaud, and Francis, Frédéric
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, pestřenkovití, slunéčkovití, Syrphidae, Coccinellidae, Chrysopidae, agri-environmental measure, conservation biological control, wildflower strips, functional diversity, Rao's index, 2, and 59
- Language:
- English
- Description:
- Among the semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields are potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesized that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators than mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, start and duration of flowering, height and flower class, primarily based on corolla morphology). In both years, the species of flowering plants in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realized functional diversity in each plot calculated. Over the two years, a high functional diversity was not associated with high abundance and richness of aphid predators. Moreover, ladybeetles, which made up the majority of the predators trapped, were more abundant in mixtures with very low or intermediate functional diversity at sowing, especially in 2014. We hypothesize that certain flowers, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently abundant to support them. Our results present novel information that could be used for developing flower mixtures that provide effective ecosystem services, such as pest control., Séverin Hatt, Roel Uyttenbroeck, Thomas Lopes, Pierre Mouchon, Julian Chen, Julien Piqueray, Arnaud Monty, Frédéric Francis., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
35. Do sexually dimorphic glands in the harvestman Gryne perlata (Arachnida: Opiliones) release contact pheromones during mating?
- Creator:
- Dias, Jéssica M. and Willemart, Rodrigo H.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, pavoukovci, sekáči, arachnids, Opiliones, Arachnida, Laniatores, Cosmetidae, Gryne perlata, Gonyleptidae, Discocyrtus pectinifemur, chemical communication, copulation, sexually dimorphic glands, 2, and 59
- Language:
- English
- Description:
- There are records of glands that produce sexual pheromones that are released into the environment or applied directly on sexual partners. Within Opiliones (Arachnida), several harvestmen in the suborder Laniatores have sexually dimorphic glands on legs I and IV, the mode of use of which is recorded only in two species but their function is unknown: while walking, males rub the glands against the substrate or against their body. Here we test an alternative and non-exclusive hypothesis that the glands present on the legs of male Gryne perlata (Cosmetidae) produce contact pheromones used in mating. We predicted that males would touch the females with the gland openings or with other male body parts previously rubbed by these glands. We also predicted that there are chemoreceptors on those parts of the females where males touch them. We analyzed 13 videos of G. perlata mating, a species in which the males have glands on legs I and IV of unknown function. We also analyzed 14 videos of Discocyrtus pectinifemur (Gonyleptidae) mating as a control, a species that lacks these glands. Finally, we looked for chemoreceptors on the legs of female G. perlata using a scanning electron microscope. During copulation, males of both species rubbed the legs of females with their first pair of legs, but not with the regions of these legs where the openings of the glands are. The fourth pair of legs were only used to support the body. Rubbing other body parts of the female by males with their glands was not observed during mating. Setae on the legs of the female did not have tip pores and therefore do not seem to be chemoreceptors. We therefore did not find any evidence that these sexually dimorphic glands in G. perlata release contact pheromones during mating., Jéssica M. Dias, Rodrigo H. Willemart., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
36. Do the arthropod communities on a parasitic plant and its hosts differ?
- Creator:
- Lázaro-González, Alba, Hódar, José A., and Zamora, Regino
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, jmelí bílé, borovice, polokřídlí, Viscum album, Pinus, Hemiptera, Mistletoe, hemiparasitic plant, pine host, arthropod communities, specialist insect, Cacopsylla visci, Pinalitus viscicola, Anthocoris visci, 2, and 59
- Language:
- English
- Description:
- Parasitic plants growing on tree branches may be a novel niche and phytoresource for arthropods. The spatial continuity between hosts and their parasites in canopies might provide a homogeneous environment for arthropod communities, but differences in mistletoe leaves and host needles could be exploited by different species of arthropods. Therefore, it is important to determine insect-community assemblages in order to discover the role of parasitic plants as a different habitat for arthropods. Thus, we aim to evaluate the level of similarity between the arthropod community on mistletoe (Viscum album) and that on its two principal pine hosts, Black pine (Pinus nigra) and Scots pine (P. sylvestris), on a Mediterranean mountain. Our results reveal that, irrespective of the species of pine host, V. album has a stable, independent and simple arthropod trophic web, composed mainly of two specialist hemipteran herbivores, Cacopsylla visci (Psyllidae) and Pinalitus viscicola (Miridae), and a hemipteran predator, Anthocoris visci (Anthocoridae). Despite this, the composition of the arthropod communities differed significantly on both host species, with a greater richness and diversity on Scots than Black pine and these differences are not reflected in the community on mistletoe. Overall, we conclude that, although Viscum album is considered to be a pest of pine, its presence increases the heterogeneity of the forest canopy by providing a novel habitat for a new and specific community of arthropods. In addition, this is a new record for and most probably an extension of the southernmost limit of the known geographical distribution of the arthropod community inhabiting V. album., Alba Lázaro-González, José A. Hódar, Regino Zamora., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
37. Does one size suit all? Dung pad size and ball production by Scarabaeus sacer (Coleoptera: Scarabaeidae: Scarabaeinae)
- Creator:
- Sullivan, Gregory T., Ozman-Sullivan, Sebahat K., Lumaret, Jean-Pierre, Zalucki, Myron P., and Baxter, Greg
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, vrubounovití, beetles, Scarabaeidae, Coleoptera, Scarabaeus sacer, ball roller, diel cycle, dung pad, intraspecies competition, nocturnal, seasonal, telecoprid, 2, and 59
- Language:
- English
- Description:
- Large, ball rolling dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are competitively dominant and can strongly influence community succession in dung pads. Ball production by Scarabaeus sacer Linnaeus was recorded in the Kizilirmak Delta on the Black Sea coast of Turkey by using artificial dung pads from 125 g to 2,000 g. Utilisation of pads across the 16-fold range of pad sizes demonstrated behavioural variation that may reduce intraspecies competition. Ball production was highly concentrated, with 66 balls (61%) produced from 8 pads of the 3 largest pad sizes, which may be related to chemical attraction between males and females. Ball size increased with increasing pad size (P < 0.05) but the number of balls produced per 100 g of dung decreased with increasing pad size (P < 0.01). Pad size for maximum ball production and ball size were 1,371 g and 1,260 g, respectively. The highest and lowest percentage of dung used for ball production was 43% of 125 g pads and 13% of 2,000 g pads, respectively. Ball production and time of day were significantly related (P < 0.01); S. sacer was almost exclusively nocturnal, with 59% of all balls produced between 21.00 and 22.00. This optimum period for ball production early in the night may be a compromise between reduced risk of predation and the increased energy costs of ball production as the temperature falls., Gregory T. Sullivan, Sebahat K. Ozman-Sullivan, Jean-Pierre Lumaret, Myron P. Zalucki, Greg Baxter., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
38. Double strand RNA-mediated RNA interference through feeding in larval gypsy moth, Lymantria dispar (Lepidoptera: Erebidae)
- Creator:
- Ghosh, Saikat Kumar B. and Gundersen-Rindal, Dawn E.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, bekyně (motýli), příjem potravy, Lymantria, ingestion, Lepidoptera, Erebidae, Lymantria dispar, gypsy moth larvae, RNAi, dsRNA, 2, and 59
- Language:
- English
- Description:
- RNA interference (RNAi) technology uses dsRNAs to silence specific targeted genes by downregulating their expression. It has become a potent tool for functional and regulatory studies of insect genes and has potential to be applied for insect control. Though it has been challenging to generate effective RNAi in lepidopteran insects, in the current study this technology was applied to develop specific RNAi-based molecular tools that could be used to negatively impact the invasive lepidopteran forest pest, gypsy moth (GM). GM midgut-specific genes were selected for dsRNA design from larval transcriptome profiles. Two methods were used to produce specific dsRNAs, bacterial expression and in vitro synthesis, which were then fed per os to GM larvae. Depletion of uncharacterized gene targets known as locus 365 and locus 28365, or their stacked combination, depleted target transcripts in a sequence specific manner and resulted in 60% reduction in body mass. Treated GM females that were able to moult to the adult stage displayed an approximately two-fold reduction in egg masses. These have potential to be developed as molecular biopesticides for GM., Saikat Kumar B. Ghosh, Dawn E. Gundersen-Rindal., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
39. Dragonflies and damselflies (Odonata) in urban ecosystems: a review
- Creator:
- Villalobos-Jiménez, Giovanna, Alison M. Dunn, and Hassall, Christopher
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, vážky, životní prostředí měst, velkoměsta, biodiverzita, bioindikátory, Odonata, urban ecology, cities, biodiversity, bioindicators, anthropogenic stressors, odonates, dragonflies, damselflies, ecotoxicology, behaviour, life history, phenotypic variation, ecological traps, 2, and 59
- Language:
- English
- Description:
- The expansion of urban areas is one of the most significant anthropogenic impacts on the natural landscape. Due to their sensitivity to stressors in both aquatic and terrestrial habitats, dragonflies and damselflies (the Odonata) may provide insights into the effects of urbanisation on biodiversity. However, while knowledge about the impacts of urbanisation on odonates is growing, there has not been a comprehensive review of this body of literature until now. This is the first systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems. From this research, 79 peer-reviewed papers were identified, the vast majority (89.87%) of which related to studies of changing patterns of biodiversity in urban odonate communities. From the papers regarding biodiversity changes, 31 were performed in an urban-rural gradient and 21 of these reported lower diversity towards built up city cores. Twelve of the cases of biodiversity loss were directly related to the concentrations of pollutants in the water. Other studies found higher concentrations of pollutants in odonates from built-up catchments and suggested that odonates such as Aeshna juncea and Platycnemis pennipes may be candidate indicators for particular contaminants. We conclude by identifying current research needs, which include the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution., Giovanna Villalobos-Jiménez, Alison M. Dunn, Christopher Hassall., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
40. Dříve vyslovená přání (advance directives). Právní a etické úvahy
- Creator:
- Adam Doležal
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Právo, zdravotnické právo, bioetika, eutanazie, osobní autonomie, medical law, bioethics, euthanasia, personal autonomy, dříve vyslovená přání, DNR, rozhodování na konci života, advance directives, living will, end-of-life decisions, 16, and 34
- Language:
- Czech
- Description:
- Příspěvek se zabývá institutem tzv. dříve vyslovených přání, přičemž zahrnuje jak některé právní, tak i některé etické problémy. Zejména se soustředí na otázky, které ještě v české odborné literatuře nebyly řešeny. V první části je shrnuta užívaná terminologie a historie institutu. Kromě toho jsou zmíněny tři modely dříve vyslovených přání, tzv. living will, substitute decision-making (rozhodování zvoleným zástupcem) a konečně tzv. values history (historie hodnot pacienta). Ve druhé části je shrnuta úprava v České republice. Ve třetí se pak článek zabývá konkrétními právními a etickými problémy., This article deals with advance directive and some legal and ethical issues associated with them. Its main purpose is to show some problems which haven´t been solved in Czech professional literature. The first part of this article summarizes terminology and history of this medical institute. Three models of advance directives are mentioned as well - living will, substitute decision-making and values history. The second part summarizes Czech legislation and its development. The last part speaks about some crucial ethical and legal issues associated with advance directives., and Adam Doležal.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public