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Semi-empirical predictive calculation of the thermal-physical properties of potassium-sodium melts based on their component data
No full textUse of liquid-metal coolants in nuclear power plants has been the cause of unfailing interest in thermal-physical properties of metals and their alloys from both experimentalists and theorists. Power polynomials are used by experimentalists to approximate temperature changes in heat capacity, the coefficient of thermal linear (volume) expansion and other quantities. These polynomials have different form in different temperature intervals and need to be joined at the interval ends. This approach creates a number of difficulties in developing a unified methodology for calculating not only the thermal functions of metals, but also for predicting the behavior of their melts and alloys. The following was used in the paper to solve the problem at hand: the author’s model of a two-phase local-equilibrium region (with different order parameters) and the modified rule of component mixing, taking into account the coordinated arrays of experimental data on the initial metals for calculating predictively the thermal-physical performance of potassium and sodium melts. It has been shown that using the model of a two-phase local-equilibrium region, new approximating functions and empirical formulas lead to a sufficiently adequate estimation of heat capacities, thermal linear expansion coefficients, densities, thermal conductivities and thermal diffusivities of melts. A discrepancy has been found between the mathematical description of the thermal conductivity of the K56Na44 melt and its experimental values
Integrative taxonomy describes a new species of the genus Sinocyclocheilus (Cypriniformes, Cyprinidae) from the Beipanjiang River, Guizhou Province, southwest China
No full textWe describe a new species, Sinocyclocheilus panzhouensis sp. nov., from Panzhou City, Guizhou Province, China, using morphological and genetic evidence. Phylogenetic analysis of mitochondrial cytochrome b (Cyt b) and NADH dehydrogenase subunit 4 (ND4) sequences reveals distinct genetic divergence from related species, with genetic distances ranging from 1.7–14.2% in Cyt b and 1.2–12.6% in ND4. Morphologically, S. panzhouensis sp. nov. is characterised by absence of a horn-like structure and indistinct elevation at the head-dorsal junction; body covered with tiny scales, with irregular black markings; wide mouth, 7.8–9.3% of standard length and longer pectoral fin 17.9–30.6% of standard length; last unbranched ray of dorsal-fin with weak serrations along posterior margin; tip of pectoral fins not reaching the pelvic-fin origin; lateral line complete and curved, with pores 71–79; and eight rakers on the first gill arch. This discovery raises the number of Sinocyclocheilus species in Guizhou to 19, with five species found in the Beipanjiang River. This study highlights the need for further surveys in Guizhou to explore the full species diversity of the genus
High-level phylogenetic relationships within Pezizomycotina revisited
No full textHere, we re-examine the high level phylogeny of Pezizomycotina with special attention to the recently proposed phylogenomic hypothesis (Díaz-Escandón et al. 2022) that “morphologically hyperdiverse” Candelariomycetes, Coniocybomycetes, Geoglossomycetes, Lichinomycetes, Sareomycetes and Xylonomycetes (henceforth referred to as classes sensu stricto (s.s.)) should be united in a class Lichinomycetes (henceforth referred to as Lichinomycetes sensu lato (s.l.)), based on their common origin. Our examination revealed that the orthology of the aligned character states in the data used to produce this result is questionable due to the presence of poorly-aligned, indel-rich vertical alignment partitions, missing data and heterogeneous sequences. Our analyses of a thoroughly curated phylogenomic dataset and its subset with reduced compositional heterogeneity indicated that the fungi included in the Lichinomycetes s.l. form six independent lineages, of which two correspond to Geoglossomycetes s.s. and Candelariomycetes s.s. and others do not correspond to the taxonomic delimitations of the previously defined classes. Based on the results obtained here, we propose to revise the class Lichinomycetes to include Lichinomycetes s.s., Coniocybomycetes s.s. plus some incertae sedis genera (Caeruleum, Thelocarpon, Piccolia, Sarcosagium and Vezdaea). In our analysis, Xylona (Xylonomycetes s.s.) plus Sarea (Sareomycetes s.s.) were found to form an early diverging lineage within the branch also subtending Arthoniomycetes plus Dothideomycetes, which warrants the conclusion to include these two genera in a single class, whereas Symbiotaphrina, initially assigned to Xylonomycetes s.s., was found to split off the tree backbone earlier and, thus, should be treated as a separate lineage
Integrating plot-based methods for monitoring biodiversity in island habitats under the scope of BIODIVERSA + project BioMonI: Tree monitoring in Terceira, Tenerife and Réunion Islands
No full textOceanic islands are globally recognised for their exceptional levels of biodiversity and endemism, often resulting from unique evolutionary processes in isolated environments. However, this biodiversity is also disproportionately threatened by anthropogenic pressures including habitat loss, invasive species and climate change. Targeted, long-term biodiversity monitoring is essential for detecting changes in these vulnerable ecosystems and providing information for conservation strategies.The EU BIODIVERSA + project BioMonI aims at building a global long-term monitoring network specifically tailored to the pressing needs of biodiversity conservation and monitoring on islands. In BioMonI, we use a novel approach that considers mapping previous and current monitoring schemes on islands, developing a harmonised monitoring scheme for island biodiversity and mobilising existing monitoring data. We are assembling data from BioMonI-Plot, a long-term vegetation plot network to understand biodiversity and ecosystem change. It will use baseline data from three focal archipelagos (Azores, Canary Islands and Mascarenes), but we aim to mobilise data from archipelagos worldwide.Plot-based data are a cornerstone of effective biodiversity monitoring on islands. These standardised data collections within permanent plots allow for consistent, replicable observations across temporal and spatial scales. Initiatives like the Global Island Monitoring Scheme (GIMS) highlight the value of permanent plots in capturing ecological gradients and anthropogenic disturbance patterns. Such data underpin the detection of subtle shifts in community composition, functional diversity and species distributions, which are critical for assessing the effectiveness of conservation actions and predicting future ecological scenarios.In summary, plot-based data are indispensable for targeted and effective biodiversity monitoring on islands. They provide the empirical backbone necessary to provide information for adaptive management strategies and contribute to global biodiversity targets.The BioMonI-Plot baseline data consist of 10 plots in each of the following islands: Terceira (Azores), Tenerife (Canaries) and Réunion Island (Mascarenes). As a first step, we describe the diversity and abundance of all woody species shoots with a diameter at breast height (DBH) = 1 cm in each of the 10 plots of each Island. The majority of taxa belonged to the phylum Magnoliophyta, which accounted for 96.66% of the total species and subspecies, followed by Pteridophyta (2.22%) and Pinophyta (1.11%). Réunion Island exhibited the highest species richness, with 66 identified taxa, followed by Tenerife (16 taxa) and Terceira (11 taxa). Only one species, Morella faya, was shared between the islands, occurring in both Terceira and Tenerife. Most of the recorded species were classified as endemic according to their colonisation status. Specifically, 32 species were endemic to the Mascarene Islands, 22 to Réunion, nine to the Azores, eleven to Macaronesia and four to the Canary Islands.The data presented in this Data Paper provide a valuable proxy for evaluating the ecological integrity and overall habitat quality of native montane forests across three oceanic archipelagos: the Azores, Canary Islands and Mascarene Islands. By focusing on tree species as primary ecological indicators, the dataset offers insights into essential structural and compositional attributes of these ecosystems, including species richness, relative abundance and patterns of dominance.The comprehensive species-level information contained in this dataset allows for comparisons of forest composition across islands and biogeographic regions, contributing to our understanding of insular forest dynamics, endemism patterns and conservation priorities in tropical and subtropical montane environments
A taxonomic review of Bagarius catfish (Siluriformes, Sisoridae) in the Salween and Irrawaddy rivers, with descriptions of two new species from China and Myanmar
No full textThe genus Bagarius is a group of large, benthic, predatory catfishes found in South and Southeast Asia. Two new species of Bagarius, B. protos Zeng & Chen, sp. nov., and B. dolichonema Zeng & Chen, sp. nov., are described from the Salween River Basin, Yunnan Province, China, and Irrawaddy River Basin, Myanmar, respectively. Bagarius protos and B. dolichonema both differ from B. vegrandis and B. suchus in their large size and the adipose-fin origin being nearly vertical to the anal-fin origin. Bagarius protos most closely resembles B. lica and B. rutilus in overall morphology but can be distinguished from B. lica by the absence of the brow ridge formed by the lateral margin of the frontal and from B. rutilus by the dark yellow (instead of orange) coloration of the fins in life. It further differs from two other congeners in its short filamentous extensions of the pectoral-fin spine. Bagarius dolichonema is morphologically and genetically most similar to B. bagarius; it can be distinguished from B. bagarius by strong dorsal spines slightly flattened immediately anterior to the adipose fin, distally slender neural spines of the 4th–6th vertebrae, and shorter filamentous extensions of the pectoral-fin spine. This new species further differs from three other congeners by its longer filamentous extensions of the pectoral-fin spine and weak notches in the anterodorsal margin of the first dorsal pterygiophores. Molecular phylogeny based on the cytochrome c oxidase subunit I (COI) gene also confirms the validity of these two new species. The estimated K2P genetic distances between B. protos and congenerics range from 8.0% to 12.6%, and between B. dolichonema and congenerics range from 5.7% to 12.1%
Stellaria yabulaiensis (Caryophyllaceae), a new species from Inner Mongolia, China
No full textStellaria yabulaiensis (Caryophyllaceae), a new species from Inner Mongolia, China, is described and depicted with photographic illustrations. It is similar to S. bistyla, from which differs in its slender fibrous root, longer leaves and pedicel, occurrence of three styles, and more seeds. A morphological comparison among the new species and the similar ones is also provided
Fungal frontiers in toxic terrain: Revealing culturable fungal communities in Serpentine paddy fields of Taiwan
No full textSerpentine soils are predominantly distributed along the Circum-Pacific margin and the Mediterranean, including eastern Taiwan. These soils are characterized by high levels of heavy metals, including nickel and chromium, and a low calcium-to-magnesium ratio, creating a unique environment that fosters microorganisms with specialized traits. In this study, culture-dependent isolation methods were used to elucidate the composition of culturable fungal communities in serpentine-characterized paddy fields in eastern Taiwan. A total of 154 fungal isolates were isolated from serpentine paddy fields in eastern Taiwan. These isolates were grouped into 79 strains based on colony morphology and were subsequently evaluated through morphological and multi-locus phylogenetic analyses. The results revealed that 60% of the strains belong to the class Dothideomycetes, followed by 21% in Sordariomycetes and 19% in Eurotiomycetes. At the genus level, Westerdykella was the dominant genus, presenting 35% of the total of isolated strains, followed by Pyrenochaetopsis (20%), Talaromyces (19%), and Pseudorhypophila (8%). The study reports 11 novel species: Cylindrotrichum formosanum sp. nov., Dimorphiseta formosana sp. nov., D. serpentinicola sp. nov., Parasarocladium formosum sp. nov., Phialoparvum formosanum sp. nov., Poaceascoma serpentinum sp. nov., Pseudorhypophila formosana sp. nov., Sarocladium formosanum sp. nov., S. serpentinicola sp. nov., Talaromyces taiwanensis sp. nov., and Westerdykella formosana sp. nov. Additionally, 11 known species are reported for the first time in Taiwan: Pseudothielavia terricola, Pseudoxylomyces aquaticus, Pyrenochaetopsis oryzicola, Py. paucisetosa, Setophaeosphaeria microspora, Talaromyces adpressus, T. thailandensis, Westerdykella aquatica, W. capitulum, W. dispersa, and W. globosa. In addition, this study presents the first documented asexual morph within the genus Poaceascoma, represented by P. serpentinum. These discoveries will be valuable for future evaluations of the potential uses and functions of these species as bioremediation agents
Synthesis, biological evaluation, and molecular docking of benzhydrazide derivatives
No full textIn the pursuit of discovering and developing compounds with antioxidant and other biological activities, we designed, synthesized, and evaluated 10 hydrazide-hydrazone derivatives of 4-hydroxybenzohydrazide (ohbh1-10) as potential antioxidants. The compounds were synthesized using a Milestone FlexiWave microwave reactor, which significantly reduced reaction times and improved product yields. The radical-scavenging activities of the synthesized derivatives were assessed through DPPH and ABTS assays, revealing moderate antioxidant activity compared to the standard antioxidant, Trolox. To explore their potential biological applications, molecular docking simulations were performed to evaluate the binding affinities of the hydrazide-hydrazones within the active sites of monoamine oxidase B (MAO-B) and acetylcholinesterase (AChE). The in silico studies indicated that ohbh10 could act as a dual inhibitor of MAO-B and AChE. Additionally, ADME predictions for ohbh10 demonstrated favorable pharmacokinetic properties, including good blood-brain barrier (BBB) permeability and gastrointestinal absorption. Future work will focus on introducing additional hydroxyl groups into the molecular framework to enhance radical-scavenging properties. Furthermore, the molecular docking results will be validated through in vitro experiments to confirm the dual inhibitory potential of ohbh10 against MAO-B and AChE
Energetic metabolism and condition indices in native versus invasive common waxbills
No full textInvasive alien species (IAS) pose a serious threat to global biodiversity, and unravelling the mechanisms driving their expansion across new ranges remains an important challenge for ecosystem conservation. Assessing similarities and differences in species’ traits and phenotypic fitness proxies between native and invasive populations can show how species may have locally adjusted in the new areas and their capacity to expand further. Here, we compare basal metabolic rates (BMR), body and nutritional condition (based on feather proxies) and body size between native (South Africa) and invasive (northern and southern Portugal) common waxbills (Estrilda astrild). As expected, given prevailing ambient temperatures - similar between South Africa and northern Portugal but hotter in southern Portugal - our results showed that mass-independent BMR was similar between individuals from South Africa and northern Portugal, but lower in individuals from warmer southern Portugal. However, contrary to our expectations based on the enemy release hypothesis, feather density was higher in South African birds, challenging the assumption that invasive populations outperform their native counterparts. Additionally, feather growth rates trade-off with feather quality in the introduced populations, indicating that they may face energetically challenging environments in their invaded range. Common waxbills in South Africa were larger than those in Portugal, but further analyses showed that these size differences between native and invasive birds may be influenced by introduction history rather than ecological factors alone. This study highlights the importance of considering both native and invaded ranges when studying invasive species and provides insights into the strategies used by waxbills to thrive in different environments
Temporal and spatial distribution patterns of dipteran assemblages in common teasel (Dipsacus fullonum L.) phytotelmata: Insights from eastern Slovakia
No full textThe common teasel (Dipsacus fullonum L.) represents a unique and almost unknown aquatic ecosystem referred to as phytotelma, identified almost a century ago by Varga in 1928. The present study investigates the ecology of dipterans inhabiting the phytotelmata of the teasel in eastern Slovakia. The research, conducted from May to August (11.5.2016 – 16.8.2016), focused on the temporal and spatial distribution of organisms, mainly Dasyhelea spp. (Ceratopogonidae) and Metriocnemus eurynotus (Holmgren, 1883) (Chironomidae), in the phytotelmata. A total of 1429 dipteran individuals from six families were identified, with Dasyhelea spp. and M. eurynotus dominating the samples. The temporal and spatial dynamics of the larval and pupal stages were observed. M. eurynotus occurred mainly in the lower levels early in the season and Dasyhelea entered the higher levels during the M. eurynotus abundance decline. Unexpectedly, Dasyhelea pupae were observed actively moving out of the water on the plant stems between phytotelmata levels. The study highlights the simplicity and extremity of the teasel aquatic environment and provides insights into ecological processes, such as distribution, colonisation and species interactions within the teasel ecosystem. The results contribute to the broader understanding of phytotelma ecology and highlight the importance of the common teasel as a unique habitat for dipteran communities