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First data on the genetic structure of Trachemys scripta populations in Sicily (Testudines: Emydidae)

Vecchioni Luca, Marrone Federico, Arculeo Marco, Vamberger Melita

Journal of Water and Land Development

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2022

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Special Issue

139--145

EN

The pond slider Trachemys scripta is one of the most widespread alien turtle species in the world. Its unregulated trade and the consequent uncontrolled releases into the wild led to negative impacts on the native turtles of the invaded areas. In Italy, alien pond sliders are widely spread, and the occurrence of hatchlings and well-established populations is known in some areas. However, to date in Sicily, only a single female of Trachemys scripta laying eggs was reported. Besides that, nothing is known about the actual reproduction success and establishment of self-sustaining T. scripta populations in Sicily. Therefore, based on 14 previously characterised highly polymorphic microsatellite loci, we aimed to unravel if the alien turtles successfully reproduce in Sicily, in both natural and semi-natural areas (i.e., lake “Biviere di Gela” and “Parco d’Orléans”, respectively). Our results show a clear structuring of the two studied populations. Several full-sibling relationships between the sampled turtles were found, suggesting actual reproduction in the wild of the pond sliders in Sicily. However, further sampling is desirable since no parent-offspring relationships were observed in the studied populations. Due to our results, systematic monitoring of alien pond sliders in the whole of Sicily is crucial for better planning of mitigation strategies in order to protect the native biota of Sicilian inland waters.

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Su-22 and MiG-29 aircraft as air-launch platforms for space rockets

Olejnik Aleksander, Zalewski Piotr

Biuletyn Wojskowej Akademii Technicznej

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2020

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Vol. 69, nr 3

89--103

EN

The work is an announcement on the current state of the research project implementation. The study presents the results of an analysis of the project’s research area. On this basis, the two-stage micro-satellite launch system was selected. The system, a space-kit is based on an adopted combat aircraft carrying a satellite-laden rocket that is fired at the maximum altitude. As a potential transport platform, two withdrawn supersonic aircraft were selected: the MiG-29 and the Su-22. A dedicated mission-laden rocket is to be carried under the fuselage. Preliminary analyses have shown that the aircraft indicated with the proposed mission profile will successfully carry out the task of launching a hypothetical rocket with a payload of at least 10 kg into low earth orbit. This confirmed the merits of the basic thesis of the research project. For the analysis of the aeromechanical properties of the kit, both 3D digital models for computer simulations and physical models scaled for tunnel tests were developed. Laser scanners were used to map aircraft geometry, and measurements were made on Su-22 and MiG-29 aircraft in the aviation laboratory of the Military University of Technology. Using three-dimensional scaled models generated in a CAD environment, physical solid models were printed for wind tunnel investigations. Preliminary computer simulations conducted in the ANSYS Fluent system did not point out any negative impact of the rocket on aerodynamic characteristics and stability of the both carrier aircraft.

PL

Praca jest komunikatem dotyczącym stanu realizacji projektu badawczego. W opracowaniu zaprezentowano wyniki analizy obszaru badawczego projektu. Na tej podstawie dokonano wyboru platformy-nosiciela rakiety kosmicznej. Dwustopniowy system do wynoszenia mikrosatelity bazuje na zaadaptowanym samolocie bojowym przenoszącym rakietę z ładunkiem satelitarnym, która odstrzeliwana jest na maksymalnie osiąganej wysokości. Jako potencjalną platformę transportową wytypowano dwa wycofywane ze służby bojowe samoloty naddźwiękowe: MiG-29 oraz Su-22. Wybrana rakieta z ładunkiem misyjnym ma być przenoszona pod kadłubem. Wstępne analizy wykazały, że wskazane samoloty przy zaproponowanym profilu misji z powodzeniem wykonają zadanie wyniesienia hipotetycznej rakiety z ładunkiem użytecznym o masie co najmniej 10 kg na niską orbitę okołoziemską. Potwierdziło to zasadność podstawowej tezy projektu badawczego. Dla potrzeb analizy własności aeromechanicznych zestawu opracowano zarówno modele cyfrowe 3D do symulacji komputerowych, jak i fizyczne modele skalowane do badań tunelowych. Do odwzorowania geometrii samolotów wykorzystano skanery laserowe, a pomiary wykonano na egzemplarzach samolotów Su-22 oraz MiG-29 znajdujących się w zasobach bazy laboratoryjnej Instytutu Techniki Lotniczej WML WAT. Wykorzystując trójwymiarowe modele skalowane wygenerowane w środowisku CAD, wydrukowano fizyczne modele bryłowe do badań w tunelu aerodynamicznym. Wstępne symulacje komputerowe przeprowadzone w systemie ANSYS Fluent nie wykazały negatywnego wpływu rakiety kosmicznej na charakterystyki aerodynamiczne i stateczność samolotu-nosiciela.

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On the mutation model used in the fingerprinting DNA

Krajka Andrzej, Panasiuk Ireneusz, Misiura Adam, Wójcik Grzegorz M.

Bio-Algorithms and Med-Systems

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2020

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Vol. 16, no. 4

art. no. 20200057

EN

Objectives: The most common technique of determining biological paternity or another relationship among people are the investigations of DNA polymorphism called Fingerprinting DNA. The key concept of these investigations is the statistical analysis, which leads to obtain the likelihood ratio (LR), sometimes called the paternity index. Methods: Among the different assumptions stated in these computations is a mutation model (this model is used for all the computations). Results and conclusions: Although its influence on LR is usually negligible, there are some situations (when the mother-child mutation arises) when it is crucial.

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Evaluation of genetic diversity and population structure of five yellow catfish Pelteobagrus fulvidraco populations by microsatellite markers

Zhong L., Wang M., Pan J., Li D., Tang S., Bian W., Chen X.

Oceanological and Hydrobiological Studies

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2018

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Vol. 47, No. 2

99--106

EN

Yellow catfish, Pelteobagrus fulvidraco, is an important commercial freshwater species in China. Knowledge about the genetic diversity of the yellow catfish is important to support the management and conservation programs, which would subsequently support the sustainable production of this species. To investigate the genetic diversity and the structure of yellow catfish in the middle and lower reaches of the Yangtze River, 125 individuals from five lakes were genotyped using 13 microsatellite markers. Moderate genetic diversity was determined in all populations, with the observed heterozygosity (HO) ranging from 0.42 to 0.49 and the expected heterozygosity (HE) ranging from 0.51 to 0.61. Low to moderate genetic differentiation among the populations was revealed from pairwise FST values (p < 0.05), as well as from analysis of molecular variance (AMOVA). The UPGMA dendrogram and Bayesian clustering analysis indicated a correlation between genetic differences and geographic distance – four populations from the lower reaches clustered together, whereas the Poyang Lake (PY) population formed a separate cluster. The present study would be helpful in the wild stock management and artificial propagation programs for yellow catfish in the middle and lower reaches of the Yangtze River.

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New microsatellite multiplex PCR sets for genetic studies of the sterlet sturgeon, Acipenser ruthenus

Kohlmann K., Kersten P., Geßner J., Onără D., Taflan E., Suciu R.

Environmental Biotechnology

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2017

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Vol. 13, No. 1

11--17

EN

Wild populations of the sterlet sturgeon, Acipenser ruthenus, are declining throughout their native ranges. In-depth knowledge of their genetic diversity and structure is urgently needed to enable the identification of management units for conservation purposes. Moreover, genetic markers are required to establish appropriate breeding schemes for supportive stocking programs and to monitor genetic changes in farmed stocks. Therefore, six species-specific, polymorphic microsatellite loci were isolated and arranged into five multiplex PCR sets together with nine loci from other sturgeon species. The diversity of these 15 microsatellites was examined in 67 sterlet individuals (20 farmed in Germany and 47 wild-caught in the Romanian part of the River Danube). The total number of alleles per locus ranged from 3 to 15 with an average of 7.20. The farmed sterlet sturgeon possessed 1 to 7 alleles per locus, with a mean of 3.13; the wild individuals were more variable, with 3 to 15 alleles per locus and a mean of 7.07. Observed heterozygosities ranged from 0 to 0.850 in the farmed individuals, and from 0.064 to 0.957 in the wild individuals. Indications of inbreeding were only found in the wild sterlet sturgeon (FIS=0.062). The genetic differentiation of the two sterlet groups was significant (FST=0.1186). The high sensitivity and discriminatory power of the 15 loci was indicated by the very low overall probability of identity for siblings (PIsib=5.099x10-5) and the high accuracy of self-classification (66 out of the 67 individuals (98.51%) were correctly identified). Thus, these newly developed multiplex PCR sets are a valuable genetic tool for identifying management units for species conservation, sustainable fisheries and aquaculture.

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Tracing the genetic origin of brown trout (Salmo trutta) re-colonizing the Ecker reservoir in the Hartz National Park, Germany

Kohlmann K., Wüstemann O.

Environmental Biotechnology

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2012

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Vol. 8, No. 2

39--44

EN

The Ecker reservoir and its main tributary had been free of brown trout (Salmo trutta) for several decades due to cumulative effects of natural and anthropogenic acidification. However, after the decline of emissions in the 1990s and the resulting rise of water pH to suitable for brown trout values, the species began to recolonize its original habitats. In the main tributary first brown trout individuals were caught in 2008 and in the reservoir in later years as well. Stocking could be excluded in both areas. Therefore, the present study was aimed to trace the genetic origin of these brown trout by genotyping eight microsatellite loci in samples collected in the reservoir, its main tributary, potential refugia and - for comparison - from two areas downstream of the dam being physically isolated for about 70 years. Genetic variability within populations (average number of alleles per locus), genetic differentiation between populations (FST values and genetic distances), occurrence of certain alleles and results of assignment tests indicated that the Ecker reservoir was re-colonized from two sources: the Große Peseke, a small direct inflow into the reservoir, and the Fuhler Lohnsbach, a parallel flowing brook connected to the reservoir by a pipe. Genetic data also supported recolonization of the main tributary from the reservoir but not in the opposite direction. Moreover, bottleneck effects were evident in brown trout populations upstream of the dam compared to the two populations downstream of the dam.