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27452. Within and between species scaling in the weight, water, carbon and nitrogen contents of eggs and neonate larvae of twelve satyrine butterflies (Lepidoptera: Nymphalidae)
- Creator:
- García-Barros, Enrique
- Type:
- article, model:article, and TEXT
- Subject:
- Allometry, carbon, chorion, egg, elemental-composition, larvae, Lepidoptera, nitrogen, Nymphalidae, reproduction, and size
- Language:
- English
- Description:
- The fresh weight, dry weight, and C and N content of the eggs, egg shells and neonate larvae of several satyrines were measured. This was done in order to assess the specificity of the composition of the egg and larvae, the phylogenetic or ecological nature of the variation and the existence of structural constraints on the composition of the offspring. All the traits investigated were found to be highly species-specific. The nature of the variation was not primarily phylogenetic, suggesting that the composition of the offspring has an ecological meaning. However, only a slight association was detected between three life history traits or habitat features and the compositions of the eggs or larvae, namely: female egg dropping was associated with a high C content of the eggs, xerophily with a high C : N ratio, and a high content of N in the larvae with egg diapause. The evidence for intra-specific allometry between the traits investigated and egg weight varied among the species, suggesting that the slope of such relationship may be a specific feature. There was a close to isometric relationship between C and N contents in every species. Therefore simple C : N ratios are independent of egg size, hence they can be used directly in comparative studies. Across species analyses indicated that small offspring contained a proportionally low amount of carbon and had a high dry matter content, suggesting that selection for small eggs was accompanied by selection for an enhanced proportion of nitrogen per egg. Finally, the species with large adult females invested comparatively more nitrogen per egg, which indicates a potential, constraint-based advantage of large adult size.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27453. Within year representativity of fish assemblage surveys in two small lowland streams
- Creator:
- Takács, Péter, Sály, Péter, Specziár, András, Bíró, Péter, and Erős, Tibor
- Type:
- article, model:article, and TEXT
- Subject:
- electric fishing, wadeable streams, sample representativeness, and stream fishes
- Language:
- English
- Description:
- Although most monitoring protocols characterize fish assemblages based on one sampling occasion per year per site, it is largely unknown how well such snapshot samples characterize fish assemblages at the site and the stream levels. To address these issues, we conducted monthly samplings from March to November in 2009 in two wadeable lowland streams in the catchment area of Lake Balaton, Hungary. Five and seven sites were investigated in the two streams by electric fishing 150 m long sections. For a given sampling site, mean estimated species composition of a single survey showed on average 41 % and 35 % Jaccard index based similarity to the pooled annual samples of the site, and 90 % species representation could be reached using 5.2 and 6.4 sampling occasions on average. The representativeness of relative abundance data also varied considerably in time, showing on average 51 % and 67 % Bray-Curtis index based similarity to the pooled annual samples of the site, and reached 90 % similarity by taking 4.2 and 5.4 surveys on average per year per site. Stream level simulations of sample representativeness showed that a single survey reached on average 62.3 % and 66 % Jaccard similarity and 75.7 % and 74.8 % Bray-Curtis similarity to the whole year dataset. At the stream level, 90 % representativeness of both species composition data and relative abundance data was reached by pooling four surveys for both streams. These results indicate considerable within year variability in lowland stream fish assemblages, which should not be forgotten when evaluating monitoring data, which are based on a single survey per year.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27454. Wittig R., Siedlungsvegetation
- Creator:
- Pyšek, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27455. Wittner M. & Weiss L.M.: The Microsporidia and Microsporidiosis
- Creator:
- Weisner, J.
- Type:
- article, model:article, and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27456. Wnt/β-catenin signaling: a promising new target for fibrosis diseases
- Creator:
- Guo, Y., Xiao, L., Sun, L., and Liu, F.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, wnt, β-catenin, fibrosis, TGF-β, microRNA, 14, and 612
- Language:
- English
- Description:
- Wnt/β-catenin signaling is involved in virtually every aspect of embryonic development and also controls homeostatic selfrenewal in a number of adult tissues. Recently, emerging evidence from researches of organ fibrosis suggest that sustained Wnt/β-catenin pathway reactivation is linked to the pathogenesis of fibrotic disorders. Here we focus on Wnt/β-catenin-related pathogenic effects in different organs, such as lung fibrosis, liver fibrosis, skin fibrosis and renal fibrosis. Additionally, Wnt/β- catenin signaling works in a combinatorial manner with TGF-β signaling in the process of fibrosis, and TGF-β signaling can induce expression of Wnt/β-catenin superfamily members and vice versa. Moreover, network analysis, based on pathway databases, revealed that key factors in the Wnt pathway were targeted by some differentially expressed microRNAs detected in fibrosis diseases. These findings demonstrated the crosstalks between Wnt/β-catenin pathway and TGF-β signalings, and microRNAs, highlighting the role of Wnts in organ fibrogenesis. Most importantly, nowadays there is a variety of Wnt pathway inhibitors which give us the potential therapeutic feasibility, modulation of the Wnt pathway may, therefore, present as a suitable and promising therapeutic strategy in the future., Y. Guo ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27457. Wolbachia infection in Trissolcus species (Hymenoptera: Scelionidae)
- Creator:
- Guz, Nurper, Kocak, Erhan, Akpinar, A. Emre, Gurkan, M. Oktay, and Kilinger, A. Neset
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Scelionidae, Wolbachia, Trissolcus, sunn pest, biological control, 2, and 59
- Language:
- English
- Description:
- Wolbachia is a maternally transmitted intracellular symbiont which causes reproductive distortions in the arthropods it infects. In recent years there has been an increasing interest in using Wolbachia as a potential tool for biological control by genetic manipulation of insect pests. In the present paper we report Wolbachia infection in several Trissolcus wasps (Hymenoptera: Scelionidae) which are important egg parasitoids of the sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutellaridae). We used DNA sequence data for a gene encoding a surface protein of Wolbachia (wsp) not only to confirm Wolbachia infection but also to discriminate Wolbachia strains. Phylogenetic analyses indicated that Wolbachia strains in Trissolcus species were closely related to one another and belonged to supergroup B. Determination of the infection status of various populations, the possible role of Wolbachia in causing the incompatibility and knowledge of the reproductive compatibility of Trissolcus populations is important for the success of parasitoids in sunn pest management., Nurper Guz ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27458. Wolbachia injection from usual to naive host in Drosophila simulans (Diptera: Drosophilidae)
- Creator:
- Poinsot, Denis and Mercot, Herve
- Type:
- article, model:article, and TEXT
- Subject:
- Drosophila simulans, Drosophilidae, endosymbiosis, Wolbachia, trans-injection, cytoplasmic incompatibility, and coevolution
- Language:
- English
- Description:
- Wolbachia pipientis (Hertig) (Rickettsiaceae) is an endocellular bacterium infecting numerous species of arthropods. The bacterium is harboured by males and females but is only transmitted maternally because spermatocytes shed their Wolbachia during maturation. The presence of this endosymbiont can lead to feminisation of the host, parthenogenesis, male-killing or reproductive incompatibility called cytoplasmic incompatibility (CI). Although Wolbachia transmission is exclusively maternal, phylogenetic evidence indicates that very rare inter-species transmission events have taken place. Horizontal transmission is possible in the laboratory by transferring cytoplasm from infected to uninfected eggs. Using this technique, we have artificially infected lines of the fruit fly Drosophila simulans Sturtevant (Drosophilidae). Recipient lines came from two different D. simulans populations. One ("naive" host) is not infected in the wild. The other ("usual" host) is a population naturally carrying Wolbachia in the wild. In this second case, recipient flies used in the experiment came from a stock culture that had been cured off its infection beforehand by an antibiotic treatment. Infected D. simulans laboratory stocks were used as donors. We assessed the three following parameters: (i) trans-infection success rate (ratio of infected over total female zygote having survived the injection), (ii) level of cytoplasmic incompatibility expressed by trans-infected males three generations post-trans-infection, and (iii) infection loss rate over time in trans-infected lines (percentage of lines having lost the infection after 20 to 40 generations). We observed that parameter (i) did not differ significantly whether the recipient line came from a "naive" or a "usual" host population. However, both (ii) and (iii) were significantly higher in the "naive" trans-infected stock, which is in agreement with earlier theoretical considerations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27459. Wolf diet and its impact on the ungulates community in a new recolonized area of Western Alps: Gran Paradiso National Park
- Creator:
- Palmegiani, Ivan, Gazzola, Andrea, and Apollonio, Marco
- Type:
- article, model:article, and TEXT
- Subject:
- Canis lupus, feeding habits, recolonization, and Alpine environment
- Language:
- English
- Description:
- The aim of this study is to evaluate how wolves affected the prey community in a newly recolonization area of the Western Alps, the Gran Paradiso National Park (GPNP). Since 1960’s, this portion of the Alps hosts a multi-specific wild ungulate community. It lived in absence of large predators for more than a century. In 2006 a couple of wolves re-established in GPNP and in summer 2007 the first reproduction was documented. The present study was conducted during the following two years. In term of biomass consumed (Bio%), Alpine chamois was the main prey of wolves in all seasons (Bio% Summer 2007 = 70.13; Bio% Winter 2007/2008 = 56.99; Bio%Summer 2008 = 67.52; Bio% Winter 2008/2009 = 36.35), while roe deer were intensely consumed during the adverse season (Bio% W2007/2008 = 23.05 %; Bio% W2008/2009 = 42.47 %). Although cervids were much less abundant than bovids in the area, they represented one of the main food items of wolves, possibly because of the strong habitat overlap and altitude use between predator and preys. Moreover, the minor adaptation of cervids to the Alpine environment compared to bovids could affect their vulnerability and thus the respective consumption of the different species during the adverse season.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27460. Wolf scat detection dog improves wolf genetic monitoring in new French colonized areas
- Creator:
- Roda, Fabrice, Sentilles, Jérôme, Molins, Caroline, Duchamp, Christophe, Hansen, Éric, and Jean, Nicolas
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- conservation dogs, genetic analysis, faecal samples, large carnivores, wolves, and non-invasive monitoring
- Language:
- English
- Description:
- A detection dog and handler team were used to recover scats in areas newly colonized by wolves outside the Alpine mountains of France between October 2018 and May 2019. Survey areas were classified as occupied by a resident wolf pack (WP) or dispersers (no-WP). The efficiency of monitoring by a targeted dog-handler team was compared to opportunistic monitoring by trained observers. Use of the detection dog allowed up to 99.6% time savings relative to monitoring by trained observers. Wolf scats found by the dog represented 82.1% of genetically confirmed samples in the 12 sample units (each being 10 × 10 km) monitored by both trained observers and the dog-handler team. Occupancy modelling was used to estimate wolf detection probabilities. Ten kilometres of survey with the dog were required to reach a 98% detection probability in WP territories and 20 km to reach 96% in no-WP areas. By contrast, two years of opportunistic monitoring by trained observers were required to obtain a 90% and 76% probability of detecting wolves in WP and no-WP areas, respectively. The use of the detection dog via dog-team surveys greatly increased the collection of viable samples for genetic analysis and individual genotype identification. Our study offers further confirmation that dog-handler teams can be very effective at locating scats from target carnivores, to supplement or complement human search efforts.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public