366 results match your criteria: "Institute of Russian Academy of Sciences[Affiliation]"

While there are many works on the applications of machine learning, not so many of them are trying to understand the theoretical justifications to explain their efficiency. In this work, overfitting control (or generalization property) in machine learning is explained using analogies from physics and biology. For stochastic gradient Langevin dynamics, we show that the Eyring formula of kinetic theory allows to control overfitting in the algorithmic stability approach-when wide minima of the risk function with low free energy correspond to low overfitting.

View Article and Find Full Text PDF

Dynamics of spp. Biomass and Environmental Variability: A Case Study in the Neva Estuary (The Easternmost Baltic Sea).

Biology (Basel)

November 2024

Zoological Institute of Russian Academy of Sciences, Universitetskaya Emb. 1, 199034 Saint-Petersburg, Russia.

Predicting which non-indigenous species (NISs) will establish persistent invasive populations and cause significant ecosystem changes remains an important environmental challenge. We analyzed the spatial and temporal dynamics of the entire zoobenthos and the biomass of spp., one of the most successful invaders in the Baltic Sea, in the Neva estuary in 2014-2023.

View Article and Find Full Text PDF

Various bat species worldwide have been identified as Leptospira carriers, especially in tropical regions. In this study, we investigated the infection of Vespertilionidae bats by pathogenic Leptospira in north-west Russia. Out of 264 bats from 13 species, the urine of 24 specimens tested positive according to a polymerase chain reaction test.

View Article and Find Full Text PDF

The functional diversity structure of a community can be represented as a combination of three additive components (species dominance D, functional redundancy R, and functional diversity Q) (DRQ approach in which different facets of functional differences between species are considered simultaneously). We applied this concept to assemblages of fleas and gamasid mites parasitic on small mammals at continental (across regions of the Palearctic) and regional (across sampling sites in Slovakia) scales and asked: What are the relative effects of host species, biome/habitat type, and geographic locality on the DRQ composition of a parasite assemblage? At the continental scale, regions were partitioned according to predominant biome or geographic position in a continental section. At the regional scale, sampling sites were partitioned according to habitat type or geographic locality.

View Article and Find Full Text PDF

In this study, molecular analysis was used to show the possibility of transovarial and transstadial transmission of Borrelia valaisiana in Ixodes ricinus ticks in the natural biotopes of North-Western Russia. Female ticks collected in nature were fed on rabbits; larvae obtained from these females were fed on white mice. Eggs, female ticks after the egg deposition, larvae and nymphs of ticks after overwintering were studied for Borrelia burgdorferi s.

View Article and Find Full Text PDF
Article Synopsis
  • Seven new species of Spatulaphorus mites are identified, all found on different species of scarab beetles across various countries, including Brazil, the USA, Madagascar, Argentina, and Venezuela.
  • New species include Spatulaphorus incisus, S. spinisetus, S. brevisetosus, S. longisetosus, S. madagascariensis, S. reductus, and S. venezuelaensis, each associated with specific beetle hosts.
  • Additionally, the species Spatulaphorus imbricatipes is reclassified from the genus Pygmephorellus, and a key for identifying all species in the Spatulaphorus genus is provided.
View Article and Find Full Text PDF

A small number of chitons collected from three Emperor Seamounts was studied. Three species were identified. Of these, one species, Leptochiton milwaukensis n.

View Article and Find Full Text PDF

On some Calcaronea (Porifera: Calcarea) from the Barents Sea and adjacent Polar Basin.

Zootaxa

October 2024

Polar branch of VNIRO («PINRO» named after N.M. Knipovich); Murmansk; Russia.

Four common calcareous sponge species from the Arctic are described. One species, Sycandra rappi Morozov sp. nov.

View Article and Find Full Text PDF

Parasite traits, host traits, and environment as determinants of dark diversity affinity in flea and gamasid mite assemblages from the Palearctic.

Parasitol Res

November 2024

French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion, Israel.

A species set in a site comprises species that are present (realized diversity) and species that could inhabit this site but are absent (dark diversity; DD). DD can be both species-driven (a species' traits preclude its presence, independently of site features) and site-driven (site features preclude the species' presence, independently of its traits). DD affinity (DDA) is a measure of species' tendencies to be absent from sites that they could inhabit or of sites' tendencies to lack species that could be present.

View Article and Find Full Text PDF

Insects are poikilothermic organisms and temperature increase usually accelerates their development rates, population and distribution area growth. Therefore, it is assumed that global warming can be beneficial for the pests and other widespread species at least in the relatively cool temperate zones. However, climate change's effect on the widespread species in the Palearctic remains poorly studied.

View Article and Find Full Text PDF

One of the key strategies for tissue engineering is to design multifunctional bioinks that balance printability with cytocompatibility. Here, we describe fibrillar hydrogels produced by Schiff base formation between B-type gelatin and oxidized sodium alginate, followed by the incorporation of type I collagen, yielding a new gel (MyoColl). The resulting hydrogel exhibits a temperature- and mass-ratio-dependent sol-gel transition, showing variability of hydrogel properties depending on the component ratio.

View Article and Find Full Text PDF

Despite the achievements of modern medicine, tuberculosis remains one of the leading causes of mortality globally. The difficulties in differential diagnosis have particular relevance in the case of suspicion of tuberculosis with other granulomatous diseases. The most similar clinical and radiologic changes are sarcoidosis.

View Article and Find Full Text PDF
Article Synopsis
  • * The author argues that physiological processes are cyclical due to their genetic encoding through these cyclic codes, specifically referencing cyclic Gray codes.
  • * The research suggests that mathematical concepts from engineering, such as Karnaugh maps and Hadamard matrices, can be applied to model these inherited cyclic biostructures, highlighting the complexity of the genetic coding system in relation to evolution and function.
View Article and Find Full Text PDF

We applied a novel framework based on network theory and a concept of modularity that estimates congruence between trait-based ( = functional) co-occurrence networks, thus allowing the inference of co-occurrence patterns and the determination of the predominant mechanism of community assembly. The aim was to investigate the relationships between species co-occurrence and trait similarity in flea communities at various scales (compound communities: across regions within a biogeographic realm or across sampling sites within a geographic region; component communities: across sampling sites within a geographic region; and infracommunities: within a sampling site). We found that compound communities within biogeographic realms were assembled environmental or host-associated filtering.

View Article and Find Full Text PDF

The development of assisted reproductive technologies increases the likelihood of nanoparticles' (NPs) direct contact with gametes and embryos in in vitro conditions. Analyzing the influence of nanomaterials on the early mammalian embryo becomes increasingly relevant. This work is devoted to the effect of graphene oxide (GO) NPs on the in vitro development of mammalian embryos.

View Article and Find Full Text PDF

Dormice (family Gliridae) are an ancient group of rodents. It was fully dominant in the Oligocene and Early Miocene, and its current diversity is represented by a few extant species. A Kazakhstani endemic, the desert dormouse Selevinia betpakdalaensis is one of the most enigmatic dormouse species.

View Article and Find Full Text PDF

Correction: Morzhin, O.V.; Pechen, A.N. Control of the von Neumann Entropy for an Open Two-Qubit System Using Coherent and Incoherent Drives. 2024, , 36.

Entropy (Basel)

September 2024

Department of Mathematical Methods for Quantum Technologies & Steklov International Mathematical Center, Steklov Mathematical Institute of Russian Academy of Sciences, 8 Gubkina Str., 119991 Moscow, Russia.

In the published article [...

View Article and Find Full Text PDF

The search for active cellulolytic consortia among soil microorganisms is of significant applied interest, but the dynamics of the formation of such communities remain insufficiently studied. To gain insight into the formation of an active cellulolytic community, the experiment was designed to examine the colonization of a sterile substrate (cellulose) by microorganisms from two soil types: sod-podzolic and chernozem. To achieve this, the substrate was placed in the soil and incubated for six months.

View Article and Find Full Text PDF

Dysregulation of Transposon Transcription Profiles in Cancer Cells Resembles That of Embryonic Stem Cells.

Curr Issues Mol Biol

August 2024

Lab of the Non-Coding DNA Studies, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia.

Transposable elements (TEs) comprise a substantial portion of the mammalian genome, with potential implications for both embryonic development and cancer. This study aimed to characterize the expression profiles of TEs in embryonic stem cells (ESCs), cancer cell lines, tumor tissues, and the tumor microenvironment (TME). We observed similarities in TE expression profiles between cancer cells and ESCs, suggesting potential parallels in regulatory mechanisms.

View Article and Find Full Text PDF

Synthesis and evaluation of 5,15-diaryltetrabenzoporphyrins as photosensitizers for photo-diagnosis and photodynamic activity of tumors.

Bioorg Chem

October 2024

Department of Pharmaceutical Science and Technology, College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China; Department of Pharmacy, Huadong Hospital, Fudan University, Shanghai 200040, China. Electronic address:

Photodynamic therapy (PDT) is a well-established treatment modality, typically conducted with single-wavelength irradiation, which may not always be optimal for varying tumor locations and sizes. To address this, photosensitizers with absorption wavelengths ranging from 550 to 760 nm are being explored. Herein, a series of 5,15-diaryltetrabenzoporphyrins (ArTBPs) were synthesized.

View Article and Find Full Text PDF

A study of the enhancement of photodynamic activities of pyropheophorbide-a using PG-Ag-PPa nanoconjugates. The nanoconjugates were formulated from silver nanoparticles and PPa via amide linkage, then characterized, and their photodynamic activities were examined. The nanoconjugates displayed a higher rate of reactive oxygen species generation, commendable cellular uptake by Eca-109 cancer cells, higher photocytotoxicity toward the cancer cells and better bio-safety.

View Article and Find Full Text PDF

The brain's sensory lateralization involves the processing of information from the sensory organs primarily in one hemisphere. This can improve brain efficiency by reducing interference and duplication of neural circuits. For species that rely on successful interaction among family partners, such as geese, lateralization can be advantageous.

View Article and Find Full Text PDF