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Yeasts in the soils of the Alytus Region after the fire of the tyre processing plant /
No full textThe study aimed to investigate the prevalence and biodiversity of yeasts in the soil and water samples of the city and district of Alytus after a fire at a tire processing plant. 11 soil and 3 water samples were taken each year for the periods of 2019-2021. The yeast count in the soil samples ranged from 102 to 105 CFU/g. In water samples, the count of yeasts varied between 0.00-103 CFU/g. A total of 114 yeast isolates were isolated from the soil samples and 46 yeast species were identified. No statistically significant changes in the phyla distribution of yeast species isolated from the soil were observed during the different study periods. A total of 25 yeast isolates were isolated from the water samples and 14 yeast species were identified. Statistically significant differences in the phyla distribution of yeast species isolated from water samples were observed. The obtained research data showed that the results of all chemical soil tests do not exceed the limit values specified in Lithuanian legal acts. The obtained results of the study allow us to state that the fire at the tyre recycling plant did not affect the prevalence and biodiversity of soil yeasts, but the possibility that the effect will be noticed after a longer period of time cannot be ruled out. We believe that this study significantly contributes to the dissemination of information about the fire at the tire recycling plant and its impact on the environment, brings more clarity and reduces doubts about the possible impact of pollution on the environment
The first attempt to assess the taxonomic diversity of the Nepticulidae of Armenia resulted in the discovery of new species and cryptic taxa in the Caucasus ∗∗ /
No full textA taxonomic review of the Nepticulidae of Armenia is provided for the first time. Currently, the previously little-known fauna of the pygmy moths of Armenia consists of eight genera and 31 species, including seven new species described and illustrated in the current paper as follows: Stigmella armi Stonis, Dobrynina & Remeikis, sp. nov.; Stigmella garnica Stonis, Dobrynina & Remeikis, sp. nov.; Stigmella inopinoides Dobrynina, sp. nov.; Stigmella magicis Stonis & Dobrynina, sp. nov.; Stigmella ararati Stonis, Dobrynina & Remeikis, sp. nov.; Trifurcula vardenisi Stonis, Dobrynina & Remeikis, sp. nov.; and Etainia caucasi Remeikis, sp. nov. The most common Nepticulidae species in Armenia, Stigmella muricatella (Klimesch), still remains a taxonomic puzzle. However, the molecular sequences of the Armenian specimens and a specimen of S. muricatella from Greece were found to be similar, though clearly distinct from the widespread S. rolandi van Nieukerken due to numerous hypothetical mutational steps. Mitotype analysis revealed that the Ectoedemia specimens collected in Armenia do not belong to the expected widespread E. spinosella (Joannis) but are more similar to the less-known E. mahalebella (Klimesch). Moreover, some specimens from Armenia identified by us as Simplimorpha promissa (Staudinger) and Ectoedemia (Zimmermannia) longicaudella Klimesch may actually represent possible cryptic taxa, allopatric subspecies or species. However, from a practical point of view, the description of such difficult-to-diagnose taxa is inappropriate. Thus, we have refrained from describing such new taxa based solely on observed molecular differences
High abundance of Haemoproteus parasites in Culicoides (Diptera, Ceratopogonidae), with a confirmation of Culicoides reconditus as a new vector of these avian blood parasites /
No full textHaemoproteus parasites are the most diverse among Haemosporida. However, their natural vectors (Culicoides) are still poorly investigated and were identified for only a few parasite species and lineages. The application of an integrative approach (insect dissection, microscopic analysis, and molecular-based methods) is necessary in these studies, which have been carried out by a few research groups, mainly in Europe. The aim of this study was (i) to determine the Culicoides species that are naturally infected by Haemoproteus parasites, and which can support its complete sporogonic development, and (ii) to investigate the prevalence of Culicoides species and Haemoproteus parasite lineages in different study sites. In total, 1953 parous Culicoides females, from 11 species, were collected in four different localities in Lithuania and were dissected and analyzed using an integrative approach. The most abundant was C. pictipennis (30.3%). Parasite DNA was found in 7.9% of all investigated Culicoides, of which ~30% had sporozoites in their salivary glands, confirming their vector competence for these parasites. The Botanical Garden presented the highest number of Culicoides parous females, Culicoides species, and parasite lineages, as well as the highest positivity for sporozoites. Culicoides reconditus was confirmed as a natural vector of Haemoproteus parasites, sporozoites of six Haemoproteus lineages were reported for the first time, and 12 new interactions between Haemoproteus parasite lineages and Culicoides species were identified. Haemoproteus parasites seem to be transmitted by a high number of Culicoides species, with C. kibunensis, C. pictipennis, and C. segnis being the most important vectors
The effects of electromagnetic field radiation of extremely low frequency on growth parameters and nucleotide substitutions in L. minor clones /
No full textCurrent technologies have become a source of electromagnetic pollution resulting from artificially generated electromagnetic radiation (EMR). To understand the influence of the EMR on living organisms, we investigated the long-term effects of EMR of 50 Hz frequency on duckweed (Lemna minor) clones. Experimental groups of duckweed were treated directly and indirectly by changing EMR generating magnetic flux (MF) starting from 2 µT (0–11 weeks from the beginning of the experiment) and switching to 300 µT (12–48 weeks) MF density during the second part of the experiment. The growth parameters (plant growth, frond area, and frond number) and the point mutations appearing at the antioxidant genes DNA sequences [ascorbate peroxidase (APx), glutathione peroxidase (GPx), and catalase (Cat)] were analyzed. The significantly enhanced number of nucleotide substitutions in DNA sequences of L. minor clones directly affected by LF EMR in comparison to indirectly affected clones was revealed at the introns of APx, GPx, and Cat genes starting from the 10th week of the experiment. The results indicate that even low-dose chronic electromagnetic radiation may contribute to the changes in growth parameters and generation of point mutations in antioxidant gene sequences, especially in the intron regions
Two new species for the Afrotropic genus Leptometa: Leptometa danieli and Leptometa gabrielae (Lepidoptera, Lasiocampidae) /
No full textTwo new species of the genus Leptometa Aurivillius, 1927 are described from the rich Congolian forests: Leptometa danieli sp. n. and Leptometa gabrielae sp. n. Both species are known by short series of males which are compared with males of five other species of the genus
Antimicrobial properties of newly developed silver-enriched red onion–polymer composites /
No full textSimple low-cost, nontoxic, environmentally friendly plant-extract-based polymer films play an important role in their application in medicine, the food industry, and agriculture. The addition of silver nanoparticles to the composition of these films enhances their antimicrobial capabilities and makes them suitable for the treatment and prevention of infections. In this study, polymer-based gels and films (AgRonPVA) containing silver nanoparticles (AgNPs) were produced at room temperature from fresh red onion peel extract (“Ron”), silver nitrate, and polyvinyl alcohol (PVA). Silver nanoparticles were synthesized directly in a polymer matrix, which was irradiated by UV light. The presence of nanoparticles was approved by analyzing characteristic local surface plasmon resonance peaks occurring in UV-Vis absorbance spectra of irradiated experimental samples. The proof of evidence was supported by the results of XRD and EDX measurements. The diffusion-based method was applied to investigate the antimicrobial activity of several types of microbes located in the environment of the produced samples. Bacteria Staphylococcus aureus ATCC 29213, Acinetobacter baumannii ATCC BAA 747, and Pseudomonas aeruginosa ATCC 15442; yeasts Candida parapsilosis CBS 8836 and Candida albicans ATCC 90028; and microscopic fungi assays Aspergillus flavus BTL G-33 and Aspergillus fumigatus BTL G-38 were used in this investigation. The greatest effect was observed on Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa bacteria, defining these films as potential candidates for antimicrobial applications. The antimicrobial features of the films were less effective against fungi and the weakest against yeasts
Four new species close to Sonitha libera and Sonitha myoctona from the Congolian lowland forests (Lepidoptera, Lasiocampidae) /
No full textFour new species of the genus Sonitha Zolotuhin & Prozorov, 2010 are described: Sonitha adedapo sp. n. from Nigeria, Gabon, and DRC; Sonitha bekombo sp. n. and Sonitha ekongo sp. n. from DRC; and Soniha olanrewaju sp. n. from Nigeria and DRC. The new species are compared with closely related Sonitha libera (Aurivillius, 1915) and Sonitha myoctona Zolotuhin & Prozorov, 2010. Male adults, genitalia and maps with collecting localities are presented
Integrated stratigraphy of the Llandovery-Wenlock Boundary in the Łopianka–2 outcrop of the Sudeten Mountains, southwest Poland /
No full textStable carbon isotopic composition of organic matter (δ13Corg) analyses were carried out along the 7-m-thick section of Lower Graptolitic Shales at the Llandovery/Wenlock boundary, outcropping on Łopianka Mountain (the Łopianka-2 outcrop) in the Bardo Mountains of the Central Sudetes, Southwest Poland (eastern part of the European Variscides Belt). This study presents the first attempt to establish integrated biostratigraphical and chemostratigraphical records for Silurian strata in the Bardo Mountains. Graptolite assemblages indicate the presence of centrifugus and murchisoni biozones at the Telychian-Sheinwoodian boundary and mid-Wenlock in the investigated interval, thus continuous graptolitic succession. The succession of graptolite biozones in the upper Wenlock section could not be determined due to the collapsed strata. The isotopic signature of δ13Corg showed a positive excursion which is referred to as the Ireviken or early Sheinwoodian Carbon Isotope Excursion (ESCIE). The δ13Corg values of the Ireviken interval begin to rise higher than the first occurrence of Cyrt. bohemicus and does not coincide with the base of the murchisoni Biozone. Due to the fact that coupled carbon isotope chemostratigraphy and graptolite biostratigraphy for Silurian strata is a new approach in this region, this may serve as a standard for the Llandovery/Wenlock boundary in the area of the Saxothuringian Zone of the Central European Variscides
