bluuebunny/crossref_metadata_2025_split huggingface dataset:
DEVELOPMENT OF FEMALE REPRODUCTIVE STRUCTURES IN <i>BOECHERA</i> (BRASSICACEAE) SPECIES UNDER SEXUAL AND APOMICTIC REPRODUCTIVE MODES
Authors: Vinogradova G. Yu. , Sinelnikova N. V. , Taşkin K. M. , Brukhin V. B. 
Published: April 2024

The results of comparative embryological study of the two species from the genus Boechera (B. falcata and B. stricta), which are characterized by a sexual mode of reproduction, and the apomictic M4B accession, an ancient natural hybrid of B. stricta × B. retrofracta, are presented. A detailed description of the ovule development of the studied plants is described. A significant similarity of the ovule development has been shown; a general plan of the ovules structure is ortho-campylotropic, bitegmal, medionucellate. The development of the embryo sac in B. falcata and B. stricta corresponds to the monosporic Polygonum type; in the ovules of the M4B accession, an apomictic unreduced female gametophyte is predominantly formed as a result of Taraxacum-type diplospory. However, in this accession apomixis is facultative, since a small amount of the ovules in the ovary forms a reduced embryo sac with participation of meiosis, but unlike B. falcata and B. stricta, after the second meiotic division, a triad of megaspores is formed, of which the chalazal one is functional. In the ovules of the apomictic M4B accession, underdevelopment of the inner integument was often observed, which, apparently, correlates with arrest of the megasporocyte and embryo sac development, since destruction was often observed in ovules with a short inner integument. This abnormality is likely due to the hybrid nature of the M4B accession rather than apomixis. In this accession, the embryo is formed parthenogenetically, but its development requires endosperm, which apparently develops by pseudogamy, only after triple fusion (fertilization of the fused polar nuclei by sperm). In the absence of endosperm, the embryo perishes, and seed development is arrested.
Preparation of Ficin Complexes with Carboxymethylchitosan and <i>N</i>-(2-Hydroxy)propyl-3-Trimethyl Ammonium Chitosan and the Study of Their Structural Features
Authors: Malykhina N. V. , Olshannikova S. S. , Holyavka M. G. , Sorokin A. V. , Lavlinskaya M. S. , Artyukhov V. G. , Faizullin D. A. , Zuev Yu. F. 
Published: April 2024

Chitosan derivatives – сarboxymethyl chitosan and N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan with molecular weights of 200, 350, and 600 kDa have been synthesized. Complexes of ficin with chitosan and its named derivatives have been obtained. IR spectra of chitosan, carboxymethylchitosan, and N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan and their complexes with ficin were recorded. The analysis of the spectra confirmed the formation of conjugates between the macromolecules of polysaccharides and ficin. The optimal ratio of protein content (0.7 mg/g of carrier) and specific activity (1590 units/mg of protein) was found during the complexation of ficin with the N-(2-hydroxy)propyl-3-trimethylammonium chitosan matrix with the molecular weight 350 kDa. The efficiency of ficin complexation (in terms of specific catalytic activity) with N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan (350 kDa) exceeds that of chitosan (350 kDa) and carboxymethylchitosan (350 kDa) 2.4 and 9.8 times respectively. The types of interactions, first binding energies, amino acid composition of ficin surfaces, which interact with the carrier in the process of complexation, were studied by molecular docking. It has been established that bonds and interactions with chitosan and its derivatives are formed, among other things, with the participation of amino acid residues located near the ficin active site (Cys25 and His162), which explains the change in the proteolytic activity of the obtained complexes. Ficin complexes with N-(2-hydroxy)propyl-3-trimethyl ammonium chitosan are soluble in a wide pH range and, therefore, may be more promising than protease-chitosan complexes in the development of medical preparations and biocatalysts for the food, brewing, and leather industries.
Content of Trace Elements in Tissues of Gastropod Mollusks of the Family Buccinidae (Gastropoda) off the Coasts of South-Eastern Sakhalin (the Sea of Okhotsk)
Authors: Poltev Yu. N. , Koreneva T. G. , Maryzhikhin V. Ye. 
Published: April 2024

The content of Pb, Cd, Cu, Cr, Mn, Ni, Fe, and As in the muscle, mantle, and digestive glands of the gastropod mollusks Neptunea excelsior, N. behringiana, N. multistriata, and N. varicifera, as well as Buccinum verkruezeni, living near the coasts of the South-Eastern Sakhalin has been estimated. Representatives of the ge-nera Neptunea and Buccinum showed some differences in the ranges of variation and series of value sequences of trace element concentrations in the muscle. Exceeding the hygienic standard for the content of As in the hepatopancreas was found in all the studied mollusks, and in the muscle – in all, except for N. behringiana. The maximum permissible level of Cd concentration was exceeded in the hepatopancreas of N. multistriata.
Deep Velocity Structure and Seismicity of the Trans-Baikal Region (Along the Reference Geological and Geophysical Profile 1-SB)
Authors: Solovyev V. M. , Seleznev V. S. , Salnikov A. S. , Chechelnitsky V. V. , Gileva N. A. , Liseikin A. V. , Bryksin A. A. , Galyova N. A. 
Published: April 2024

The paper presents analysis of the seismicity and deep structure of the Trans-Baikal region in the section of the reference geophysical profile 1-SB. It was determined that the Earth’s crust and upper mantle has a complex heterogeneous structure. The thickness of the Earth’s crust varies from 40 km in the South-Eastern part of the profile and in the areas of intermountain depressions in the North-Western part, and up to 48 km in the areas of mountain ranges. The values of the boundary velocities along the M boundary also vary greatly, from higher values of 8.4‒8.5 km/s for P-waves and 4.9‒4.95 km/s for S-waves (especially in the South-Eastern part of the profile) to reduced values of 7.8‒8.0 km/s for P-waves and 4.6‒4.7 km/s for S-waves in the section of the Baikal rift zone in the North-Western part of the profile. A strong inhomogeneous structure of the medium in terms of elastic wave velocities, Vp/Vs velocity ratios, and the Poisson’s ratio is determined for the upper and the middle crust at depths of 8‒20 km. The authors determined that zones of increased seismicity are referred to blocks of the Earth’s crust with inhomogeneous velocity structure according to data of differently polarized P- and S-waves. The area of the Baikal rift zone, in the immediate vicinity of the largest Muya earthquake of 1957 with M = 7.6, is characterized by elevated inhomogeneity in the upper part of the Earth’s crust according to the elastic wave velocities and secondary parameters of the medium (Vp/Vs ratio, K* = = Vp/(γ – 1), where γ = Vp/Vs, Poisson’s ratio (σ)). A number of other inhomogeneous deep zones have also been identified in the profile based on anomalies of P- and S-waves velocities and secondary parameters of the medium, which correlate to varying degrees with seismically active sites according to long-term instrumental observations. The established unambiguous connection of large inhomogeneous zones of the upper crust of the Trans-Baikal region with the accumulation of stresses and their discharge in the form of strong earthquakes allows us to make a reasonable medium-term forecast of catastrophic events.
Geological Structure Features and Rocks Composition of Kronotsky Volcano, the Largest Stratovolcano in the Frontal Zone of the Eastern Volcanic Belt of Kamchatka
Authors: Gorbach N. V. , Rogozin A. N. 
Published: April 2024

Based on the results of 2020‒2022 field works, this paper presents a characterization of the geological structure and whole rock composition of Kronotsky volcano, one of the poorly studied eruptive centers of the Eastern Volcanic Belt (EVB) of Kamchatka. The volume of the volcanic edifice is estimated at 350 km3, that significantly exceeds the volumes of other stratovolcanoes of the frontal zone of EVB. Rocks of a volcano are presented by low-K, high-Fe tholeiitic basalts and basaltic andesites (SiO2 = 47.04–53.15 wt %; K2O = = 0.24‒0.65 wt %; FeO*/MgO = 1.2‒2.89). The basalts show extremely low contents of silica, potassium, titanium, and phosphorus in comparison with rocks of other frontal volcanoes of Kamchatka. The revealed petrochemical features were used to clarify the belonging of the objects located at the junction of Kronotsky and Krasheninnikov volcanic edifices. The obtained data will serve as the background for further petrological and geochemical studies of the volcano, and also may be used for reconstruction the sequence of volcanic events in this area, including clarification of the history of Kronotsky Lake formation.
Properties of Magmatism, Hydrothermal-Metasomatic and Filtration-Transport Processes in Uranium-Bearing Volcanogenic Structures
Authors: Petrov V. А. , Аndreeva О. V. , Poluektov V. V. 
Published: April 2024

Creation of a refined conceptual model for the formation of volcanogenic uranium deposits includes researches of the nature of magmatic, hydrothermal-metasomatic and filtration-transport processes, as well as physico-chemical conditions for the transfer and deposition of uranium. We considered these issues using the examples of the Streltsovskaya caldera and the ore field of the same name in Eastern Transbaikalia, the Xiangshan volcanic structure in South China, and the McDermitt caldera in the western United States (Oregon and Nevada states). According to the IAEA classification [Geological Classification …, 2018], these ore fields and deposits belong to the volcanogenic (volcanic-related) type. In the Streltsovsky and Xiangshan ore fields, a combination of volcanogenic in the cover and granitic (granite-related) in the basement types of deposits is observed. The main part of uranium industrial deposits of volcanic type in these regions was formed during the Mesozoic and Cenozoic epochs (although more ancient, Paleozoic, objects are known in the world). Despite different time intervals of the ore-bearing volcanogenic structures formation, many features of magmatic, hydrothermal, and filtration-transport processes in them are very similar. It is assumed that these features are due to the general influence of intraplate tectonic regimes or the evolution of the outer parts of the ocean-continent zones where magmatic activity produced volcanism of the bimodal series in the predominant sequence mafic ‒ felsic volcanics ‒ mafic, and the migration of uranium-transporting fluids was set by the joint action of seismogeodynamic and thermoconvective processes.
Ecological Analysis of the Helminth Fauna in the Dice Snake <i>Natrix tessellata</i> (Reptilia, Colubridae) from the Low Volga Region (Russia)
Authors: Kirillov A. A. , Kirillova N. Yu. , Bakiev A. G. , Gorelov R. A. 
Published: April 2024

The ecological analysis of the helminth fauna of the Dice snake Natrix tessellata from different habitats of the Astrakhan region in 2004, 2005, 2008 was carried out. The helminth community of the reptile includes 21 species of parasitic worms: 11 trematodes, 1 cestode, 8 nematodes and 1 acanthocephalan. Of these, 11 species are found in all the studied localities and form the basis of N. tessellata helminth fauna. Dominant and subdominant helminth species are found in snakes in all habitats as a result of the implementation of its main trophic relationships. Comparison of the helminth composition from different study sites showed a relatively high degree of similarity. Differences in the helminth fauna of the dice snake from different habitats are insignificant and relate to rare and accidental parasite species. Significant differences in the infection level of snakes with certain species of helminths were revealed. Most of the helminth species that parasitize the water snake have a complex life cycle. The infection of reptiles by them is determined to a large extent by biotic factors: fauna and the number of invertebrates (intermediate hosts of helminths) and vertebrates (paratenic and final hosts) in biocenosis.
Organisation of Fish Assemblage in the Mekong Delta as a Potential Indicator of Salt Water Intrusion
Authors: Malin M. I. , Malina I. P. , Hai Truong Ba , Dinh Cu Nguyen , Man Le Quang , Chi Duong Thi Kim 
Published: April 2024

The problem of salt water intrusion into the Mekong Delta is a research topic involving various branches of science. Among the causes of this phenomenon are global sea level rise and regulation of the natural river discharge due to hydropower dam construction. The scale of the delta and its water dynamics complicate instrument-based observations. Meanwhile, communities of living organisms can serve as indicators of environmental heterogeneity. This study aimed to analyze the spatial variability of fish assemblage organisation in the Mekong Delta for use as an indicator of salt water intrusion. The composition of fish assemblages in different parts of the delta were determined by midwater trawl catches during January and April 2021. A total of ~15 thousand individual fish from 74 trawl hauls were captured and analyzed. The null hypothesis was that the fish assemblages in the Mekong Delta are represented by three taxonomic complexes that are localized in the upper course (freshwater), the lower course (brackish) and the middle course (zone of the contact of the fresh and brackish waters) of the delta. The taxonomic composition of the freshwater complex is the most poor and is represented by 9 families. Meanwhile, marginal (the contact zone) and brackish complexes include 26 and 23 families, respectively. Specimens of families Cobitidae, Eleotridae, Plotosidae and Siluridae that are only found in the zone of contact of fresh and brackish waters could be considered as indicator species of its position. The actual boundaries of the brackish and freshwater complexes were determined and the distance from them to the marine delta edge equals 34 and 78 km, respectively. Assessment of the salinity values that correspond to the complex boundaries is a task for future investigation. The position of the boundaries of freshwater and brackish fish taxonomic complexes has a biological basis and could be used as an indicator of salt water intrusion into the Mekong Delta.
The Benthic Macroinvertebrates of the Kızılırmak River (Nevşehir, Turkey) and Their Relation with Environmental Variables
Authors: Aras Seval , Findik Ozlem 
Published: April 2024

Turkey has many ecological characteristics due to its geographical location, allowing it to have a rich biodiversity in freshwater ecosystems. This study was carried out on the Kızılırmak river, the longest river (1.355 km) in the country; it originates and empties into the sea within its borders. The Kızılırmak river serves various agricultural, industrial, drinking water-related, and recreational purposes and greatly contributes to the region’s economy. This study aimed to determine the distribution of the river’s macroinvertebrate fauna and evaluate the impact of environmental variables on species distribution. In addition, using species-based biodiversity indices such as the Biological Monitoring Working Party (BMWP), Average Score per Taxon (ASPT), the Shannon–Wiener index, and evenness analysis, spatial and temporal similarities and differences were determined. According to the results, the ten taxonomic groups in the Kızılırmak river belong to the following categories: Gastropoda (81.5%), Gammaridae (9.8%), Oligochaeta (6.2%) Chironomidae (2.1%), Hirudinea (0.3%), and various others (0.1%). The Shannon–Wiener and evenness indexes were 0.29–1.9 and 0.46–0.14, respectively. TR-BMWP scores are in the poor to very poor water quality classes, and the ASPT ranges from moderate to poor water quality. Correlation analysis between species and physicochemical parameters indicated that the benthic macroinvertebrate fauna diversity of the river is affected by natural and anthropogenic factors.
Mollusc <i>Anadara kagoshimensis</i>, Allien Species, in Structures of the Benthic Communities on the Crimea Shelf
Authors: Shalovenkov N. N. 
Published: April 2024

The frequency of occurrence of the mollusc-invader, Anadara kagoshimensis (Tokunaga, 1906), increased from 5 to 17–23% in zoobenthos of the South Coast of the Crimea Shelf for the last fifteen years. At the same time, the rate of the non-native mollusc was not significant and fluctuated: 0.73–23.29% from the biomass and 0.19–2.20% from abundance of the macrozoobenthos in the benthic communities. The mollusc A. kagoshimensis has been registered in the three communities: Chamelea gallina, Gouldia minima–Pitar rudis and Gouldia minima. The mollusc Anadara has not formed an independent community here. Influence of this alien species on bottom communities of the Crimean Coast was not such considerable as on bottom communities in northwest or in east parts of Black Sea Shelf. The structure of benthic communities had no significant changes on the shelf of the Southern Coast of the Crimea, compared with 70–80 of the last century. The first registration and the settlement of the mollusc-invader on the Crimea Shelf coincides with salinity decrease and temperature rise of coastal waters which are observed during last decade.
Effect of Algicide Based on Metabolites, Allelochemicals of Aquatic Plants on Seed Germination and the Development of Seedlings of Three Species of Helophytes
Authors: Lapirov A. G. , Belyakov E. A. , Lebedeva O. A. , Kurashov E. A. , Krylova J. V. 
Published: April 2024

For the first time, the effect of a patented alcoholic solution of algicide on seed germination and the development of seedlings of three species of helophytes Sparganium emersum, S. glomeratum and Schoenoplectus lacustris was studied based on gallic, tetradecanoic, heptane and octane organic acids. Significant differences were found in the effect of different algicide concentrations (0.1, 1.0 and 10.0 mg/L) on seed germination and the initial stages of seedling development of three species of helophytes. We observed the stimulation of germination of Sparganium emersum seeds at a concentration of 10.0 mg/L and inhibition of this process in S. glomeratum at concentrations of 1.0 and 0.1 mg/L. No significant effect of algicide on the germination of Schoenoplectus lacustris seeds was found. According to the degree of increase in the resistance of morphological parameters of plants to the effect of different algicide concentrations, seedlings of three species of helophytes are arranged in the following series: Schoenoplectus lacustris Sparganium glomeratum S. emersum.
MitoH3: Mitochondrial Haplogroup and Homoplasmic/Heteroplasmic Variant Calling Pipeline for Alzheimer’s Disease Sequencing Project
Authors: Zhu Congcong , Tong Tong , Farrell John J. , Martin Eden R. , Bush William S. , Pericak-Vance Margaret A. , Wang Li-San , Schellenberg Gerard D. , Haines Jonathan L. , Lunetta Kathryn L. , Farrer Lindsay A. , Zhang Xiaoling 
Published: April 2024

Background: Mitochondrial DNA (mtDNA) is a double-stranded circular DNA and has multiple copies in each cell. Excess heteroplasmy, the coexistence of distinct variants in copies of mtDNA within a cell, may lead to mitochondrial impairments. Accurate determination of heteroplasmy in whole-genome sequencing (WGS) data has posed a significant challenge because mitochondria carrying heteroplasmic variants cannot be distinguished during library preparation. Moreover, sequencing errors, contamination, and nuclear mtDNA segments can reduce the accuracy of heteroplasmic variant calling. Objective: To efficiently and accurately call mtDNA homoplasmic and heteroplasmic variants from the large-scale WGS data generated from the Alzheimer’s Disease Sequencing Project (ADSP), and test their association with Alzheimer’s disease (AD). Methods: In this study, we present MitoH3—a comprehensive computational pipeline for calling mtDNA homoplasmic and heteroplasmic variants and inferring haplogroups in the ADSP WGS data. We first applied MitoH3 to 45 technical replicates from 6 subjects to define a threshold for detecting heteroplasmic variants. Then using the threshold of 5% ≤variant allele fraction≤95%, we further applied MitoH3 to call heteroplasmic variants from a total of 16,113 DNA samples with 6,742 samples from cognitively normal controls and 6,183 from AD cases. Results: This pipeline is available through the Singularity container engine. For 4,311 heteroplasmic variants identified from 16,113 samples, no significant variant count difference was observed between AD cases and controls. Conclusions: Our streamlined pipeline, MitoH3, enables computationally efficient and accurate analysis of a large number of samples.
A Scoping Survey to Inform Design of Digital Dementia Risk Reduction Interventions for Adults Concerned about their Cognitive Health
Authors: Amos Jessica G. , Zheng Lidan , Eramudugolla Ranmalee , Andrews Sophie C. , Anstey Kaarin J. 
Published: April 2024

Background: Digital dementia risk reduction interventions are cost-effective and scalable. However, it is unknown how they are perceived by people already experiencing cognitive concerns or decline. Objective: To understand the current use, interest, and preferences for online learning courses and interest in learning about factors influencing brain health and dementia risk among adults ≥45. To explore potential differences between individuals experiencing cognitive concerns and those without. Methods: Adults aged 45 and older completed a survey on technology use and healthy ageing ( n = 249, Mean age = 65.6, 76.3% female). The Memory Assessment Clinic-Questionnaire was used to assess subjective memory decline, and 153 participants met the study criteria for cognitive concerns (≥25). Results: Almost all participants (98.4%) reported using two or more digital devices, and 51.8% reported increasing device usage following COVID-19. Most (92.1%) were interested in learning about healthy living and memory within an online course, and over 80% indicated a high interest in learning about dementia risk factors. People with cognitive concerns were more likely to report using a ‘routine or system’ to aid memory than people without (82.4% versus 62.9%, p = 0.001). However, no significant difference was found in technology use, course preferences, or interest in learning about different risk factors. Conclusions: We conclude that adults 45 years and over are interested in online methods for learning about brain health and offer unique insights into adapting dementia prevention programs for cognitive concerns.