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592. Local adaptation at fine spatial scale through chromosomal inversions and mito-nuclear epistasis: findings in Drosophila subobscura (Diptera: Drosophilidae)
- Creator:
- Savić Veselinović, Marija, Kurbalija Novićić, Zorana , Kenig, Bojan , Jelić, Mihailo, Patenković, Aleksandra , Tanasković, Marija , Pertoldi, Cino , Stamenković-Radak, Marina , and Andjelković, Marko
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Diptera, Drosophilidae, Drosophila subobscura, genetic differentiation, high dispersion, chromosomal inversion, ND5, microsatellites, and local adaptation
- Language:
- English
- Description:
- To explore local adaptation in wild populations at a fine spatial scale we characterized the genetic variability of eight closely located populations of Drosophila subobscura and its associations with microhabitat environmental conditions. Three different genetic markers were assessed: chromosomal inversions, a SNP of mitochondrial ND5 gene and nuclear microsatellites. Population genetic analyses of chromosomal variability revealed significant genetic differentiation between these populations. Gene arrangement frequencies on the E chromosome contributed most to these differences. We also investigated role of mito-nuclear epistasis in mitochondrial genome differentiation and revealed weak linkage disequilibrium (LD) exclusively between O3+4 inversion arrangement and mitochondrial DNA haplotype I in two populations. In addition, the trend in the LD between OST chromosomal arrangement and haplotype II was general in the total sample. Microsatellite analysis revealed an absence of stochastic processes, like census reduction, upon population differentiation. Only a small amount of the genetic variation is related to geographic distance, while most (97%) is attributable to other factors and in some degree to microhabitat variables (temperature, humidity). The analysis of these factors revealed they effect inversion arrangement frequencies, especially E1+2+9, EST and OST. Even though this model organism is known for its high mobility and mostly large effective population size, the results presented here reveal that local adaptations can occur even at a small spatial scale. We propose that locally adapted alleles within chromosomal inversions, as well as joint selective pressures acting on mitochondrial and nuclear genomes, are responsible for the observed adaptation to microhabitat conditions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
593. Long-term monitoring of the impact of mining operations on the ground surface at the regional scale based on the InSAR-SBAS technique, the Upper Silesian Coal Basin (Poland). Case study
- Creator:
- Kopeć, Anna, Bugajska, Natalia, Milczarek, Wojciech, and Głąbicki, Dariusz
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- InSAR, subsidence, regional scale monitoring, and Sentinel 1A/1B
- Language:
- English
- Description:
- Underground mining activity in the region of the Upper Silesian Coal Basin (USCB) results in ground displacements scattered on a large area. Both the locations and the velocities of the displacements depend on many factors, such as the current location of the mining front, the mining depth and system, as well as geological conditions. Although SAR interferometry techniques allow the monitoring of such ground displacements, in a regional scale (as is the case of the USCB) SAR images must be appropriately processed (from a number of frames and swaths), and this is the problem addressed in this article. The implementation of algorithms for analyzing time series allows observations of displacements in both time and space. The authors also analyze the influence of mining operations on the road infrastructure and mining waste heaps located in the area and investigate the potential for the monitoring of secondary influence (due to induced seismic tremors). As a result of these investigations, the article presents the quality of the InSAR-SBAS data and the potential for their employment in the measurements.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
594. Loss of Y chromosome may be a synapomorphy of the tribe Lepturini (Coleoptera: Cerambycidae: Lepturinae)
- Creator:
- Dutrillaux, Anne-Marie and Dutrillaux, Bernard
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Cerambycidae, Lepturinae, Lepturini, systematics, karyotype, and chromosome loss
- Language:
- English
- Description:
- Phylogeny and higher classification of the cerambycid subfamily Lepturinae remain controversial. Here we report the results of a cytogenetic study of 18 species currently classified in Lepturini and 12 species in other tribes of Lepturinae (1 in Oxymirini, 1 in Rhamnusiini and 10 in Rhagiini) from Western Europe. The male sex chromosome formula is XY in all Rhagiini, Oxymirini and in Grammoptera ruficornis in the Lepturini (whose tribal placement may be doubtful), and X0 in all the remaining Lepturini. The rarity of the X0 formula in other Cerambycidae indicates that the Y chromosome was lost in a common ancestor of the Lepturini or a subgroup thereof, indicating its monophyletic origin. The number of chromosomes is stable in the Lepturini that lack a Y chromosome (19,X/20,XX in males and females, respectively), but varies from 20 to 24 in the remaining genera, probably the consequence of evolution by chromosome fission. Whereas all the males with 19 or 20 chromosomes have an early gametogenesis, which is achieved before the imago stage, the species with more than 20 chromosomes seem to have a delayed male gametogenesis, which is still active in the young imagoes. The species of Rhagiini with 22 chromosomes may constitute a monophyletic group.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
595. Low seroprevalence and low incidence of infection with Toxoplasma gondii (Nicolle et Manceaux, 1908) in pediatric hematopoietic cell transplantation donors and recipients: Polish nationwide study
- Creator:
- Czyzewski, Krzysztof , Fraczkiewicz, Jowita , Salamonowicz, Malgorzata , Pieczonka, Anna , Zajac-Spychala, Olga , Zaucha-Prazmo, Agnieszka , Gozdzik, Jolanta , and Styczynski, Jan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- bone marrow transplantation, children, prophylaxis, toxoplasmosis, treatment, trimethoprime, and sulfamethoxazole
- Language:
- English
- Description:
- Toxoplasmosis is a potentially fatal complication after hematopoietic cell transplantation (HCT). Pre-transplant seropositivity of graft recipient to Toxoplasma gondii (Nicolle et Manceaux, 1908) is an important factor for disease reactivation after HCT. As toxoplasmosis epidemiology varies all over the world, we performed a Polish nationwide retrospective cohort study to determine the seroprevalence of toxoplasmosis in donors and pediatric allogeneic and autologous HCT recipients and the incidence of clinically evident toxoplasmosis in this patient group. Polish adult donors had higher anti-T. gondii seroprevalence than Polish pediatric donors (28% vs 8%; OR = 4.4; p = 0.02) and allo-HCT recipients (28% vs 17%; OR = 1.9; p = 0.01). Clinically apparent disease occurred in 1% of allo-HCT recipients: it was diagnosed by PCR as cerebral and/or ocular toxoplasmosis and successfully treated with antiprotozoal therapy. Regarding current practice, no prospective screening for infection of T. gondii in pediatric HCT centres is being performed, but, vast majority of HCT pediatric patients are receiving anti-T. gondii active prophylaxis. Since pre-HCT T. gondii serology was not assessed in all HCT; recipients, we propose this test should be a standard practice. Standardisation of management with infection of T. gondii in children after HCT is needed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
596. Low-level laser therapy attenuates arthrogenic contracture induced by anterior cruciate ligament reconstruction surgery in rats
- Creator:
- Kaneguchi, Akinori, Ozawa, Junya, Minamimoto, Kengo, and Yamaoka, Kaoru
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- anterior cruciate ligament reconstruction, low-level laser therapy, joint contracture, inflammation, and arthrofibrosis
- Language:
- English
- Description:
- Therapeutic approaches to treat joint contracture after anterior cruciate ligament (ACL) reconstruction have not been established. Arthrofibrosis accompanied by joint inflammation following ACL reconstruction is a major cause of arthrogenic contracture. In this study, we examined whether antiinflammatory treatment using low-level laser therapy (LLLT) can prevent ACL reconstruction-induced arthrogenic contracture. Rats underwent ACL transection and reconstruction surgery in their right knees. Unoperated left knees were used as controls. After surgery, rats were reared with or without daily LLLT (wavelength: 830 nm; power output: 150 mW; power density: 5 W/cm2 ; for 120 s/day). We assessed the passive extension range of motion (ROM) after myotomy at one and two weeks post-surgery; the reduction in ROM represents the severity of arthrogenic contracture. ROM was markedly decreased by ACL reconstruction at both time points; however, LLLT partially attenuated the decrease in ROM. One week after ACL reconstruction, the gene expression of the proinflammatory cytokine interleukin-1β in the joint capsule was significantly upregulated, and this upregulation was significantly attenuated by LLLT. Fibrotic changes in the joint capsule, including upregulation of collagen type I and III genes, shortening of the synovium, and thickening were caused by ACL reconstruction and seen at both time points. LLLT attenuated these fibrotic changes as well. Our results indicate that LLLT after ACL reconstruction could attenuate the formation of arthrogenic contracture through inhibition of inflammation and fibrosis in the joint capsule. Thus, LLLT may become a novel therapeutic approach for ACL reconstructioninduced joint contracture.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
597. Macroparasites and their communities of the European eel Anguilla anguilla (Linnaeus) in the Czech Republic
- Creator:
- František Moravec and Tomáš Scholz
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, ryby, druhová rozmanitost, parasitic organisms, fishes, species diversity, Labe (Česko a Německo : řeka : povodí), Dunaj (řeka : povodí), Odra (řeka : povodí), Evropa střední, Elbe River Basin (Czechia and Germany), Danube River Basin, Odra River Basin, Europe, Central, parasite fauna, host specificity, 2, and 59
- Language:
- English
- Description:
- This paper summarises the results of parasitological examinations of the European eel Anguilla anguilla (Linnaeus) in the Czech Republic, carried out at the Institute of Parasitology, Czech Academy of Sciences (previously the Czechoslovak Academy of Sciences) within the period of 50 years (1958-2008). Even though this survey is limited to the Czech Republic, it provides extensive data probably incomparable with any other study anywhere regarding the number of eels examined and parasites found. A total of 723 eels was examined from 42 localities that belong to all of the three main river drainage systems in the country, i.e. the Elbe, Danube and Oder river basins. Of the 31 species of adult and larval macroparasites including Monogenea (4 species), Trematoda (3), Cestoda (3), Nematoda (11), Acanthocephala (5), Hirudinea (1), Bivalvia (1), Copepoda (1), Branchiura (1) and Acariformes (1), most of them (30) were recorded from the Elbe River basin. These parasites can be divided into three main groups regarding their host specificity: parasites specific for eels (26%), non-specific adult parasites occurring also in other fishes (61%) and non-specific larvae (13%). The highest number (19) of parasite species was recorded in the Mácha Lake fishpond system in northern Bohemia. The parasite communities in eels from the individual localities exhibited large differences in their species composition and diversity depending on local ecological conditions. The parasite fauna of A. anguilla in the Czech Republic is compared with that in other European countries. The nematode Cucullanus egyptae Abdel-Ghaffar, Bashtar, Abdel-Gaber, Morsy, Mehlhorn, Al Quraishy et Mohammed, 2014 is designated as a species inquirenda., František Moravec, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
598. Maladaptive host choice by an alien leaf miner Phyllonorycter leucographella (Lepidoptera: Gracillariidae) has the potential to limit its invasiveness
- Creator:
- Walczak, Urszula, Bogdziewicz, Michał, Żytkowiak, Roma, Karolewski, Piotr, and Baraniak, Edward
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- motýli, vzpřímenkovití, butterflies, Gracillariidae, Lepidoptera, Phyllonorycter leucographella, invasive species, alien leaf miner, host selection, specific leaf area, infestation rate, insect development, 2, and 59
- Language:
- English
- Description:
- Alien phytophagous insects are often introduced along with their host plants, creating opportunities for troublesome invasions. Yet, not all of them are able to successfully colonize novel host plants. In this study, we investigated host selection by the alien leaf miner Phyllonorycter leucographella (Zeller, 1850) on both its original host and novel host plants in the insect's alien range. We predicted that this insect's percentage infestation of the original host would be positively related to its specific leaf area (SLA), because high-SLA leaves are nutritious and have thin cuticles, traits related to high offspring developmental success. We further hypothesized that this host selection process would apply in the selection of novel host plants. Our results show that this leaf miner selects leaves of its original host plant, Pyracantha coccinea, according to their SLA values. The SLA value was also positively related to the probability of P. leucographella infesting and successfully developing on novel host plants. The selection of high-SLA plants by the moth leads to a high developmental success on novel host plants in the first (summer) generation, but it is likely to be maladaptive in the second (overwintering) generation, because in temperate Europe, high SLA values are associated with deciduous plants that shed their leaves in autumn. It is likely that the apparent maladaptive selection of novel host plants by P. leucographella reduces the invasiveness of this pest by preventing its establishment on native plants., Urszula Walczak, Michał Bogdziewicz, Roma Żytkowiak, Piotr Karolewski, Edward Baraniak., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
599. Mandible morphology reflects the type of male antagonism in the ant genus Cardiocondyla (Hymenoptera: Formicidae)
- Creator:
- Schmidt, Christine V and Heinze, Jürgen
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, mravencovití, morfologie (biologie), Hymenoptera, ants, morphology (biology), Cardiocondyla, ergatoid males, mandibles, male antagonism, 2, and 59
- Language:
- English
- Description:
- The ant genus Cardiocondyla is characterized by wingless, ergatoid males, which in some species replace the typical winged male. Depending on species, ergatoid males engage in lethal fighting for access to sexual females, establish territories within their nests, or are mutually tolerant. Here we investigate, whether the morphology of ergatoid males and in particular the shape of their mandibles reflect phylogeny or male behaviour. In contrast to the worker mandible, which is relatively similar in shape in the ten species examined, mandibles of ergatoid males show a great variation in size and shape not only between the two clades of Cardiocondyla but also among species belonging to Cardiocondyla clade A. This diversity appears to reflect the diverse reproductive tactics of ergatoid males of different species, with extremely long, anteriorly oriented mandibles associated with indirect killing of adult competitors, while particularly short mandibles possibly constitute an adaptation to a tactic in which ergatoid males crush the cuticle of young rivals., Christine V. Schmidt, Jürgen Heinze., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
600. Markov stopping games with an absorbing state and total reward criterion
- Creator:
- Cavazos-Cadena, Rolando, Rodríguez-Gutiérrez, Luis, and Sánchez-Guillermo, Dulce María
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- hitting time, non-expansive operator, monotonicity property, fixed point, equilibrium equation, and bounded rewards
- Language:
- English
- Description:
- This work is concerned with discrete-time zero-sum games with Markov transitions on a denumerable space. At each decision time player II can stop the system paying a terminal reward to player I, or can let the system to continue its evolution. If the system is not halted, player I selects an action which affects the transitions and receives a running reward from player II. Assuming the existence of an absorbing state which is accessible from any other state, the performance of a pair of decision strategies is measured by the total expected reward criterion. In this context it is shown that the value function of the game is characterized by an equilibrium equation, and the existence of a Nash equilibrium is established.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public