bluuebunny/crossref_metadata_2025 huggingface dataset:
External strategies for enhanced sensing performance of self-powered polyvinylidene fluoride-based sensors
Authors: Wang Fang , Song Zixuan , Cai Xinchen , Guo Kai , Pan Xiaoyu , Ren Chuanlai , Li Bo
Published: February 2025

External strategies such as electrode design, stress/heat transfer improvements, microstructure optimization, and multifunctional synergy show great potential for improving sensing performance of PVDF-based sensors. Images reproduced with permission, full details in paper.
Isovalent cation substitution drives structural transformation and infrared nonlinear optical activity in Eu-based chalcogenides
Authors: Feng Ping , Zhou Sheng-Hua , Ran Mao-Yin , Li Bingxuan , Wu Xin-Tao , Lin Hua , Zhu Qi-Long
Published: February 2025

A novel Eu-based chalcogenide, β-EuZnGeS4, has been designed using an isovalent cation substitution strategy, starting from the centrosymmetric Eu2GeS4, and it demonstrates well-balanced IR NLO performance.
Pd single atoms on g-C3N4 photocatalysts: minimum loading for maximum activity
Authors: Jeyalakshmi Velu , Wu Siming , Qin Shanshan , Zhou Xin , Sarma Bidyut Bikash , Doronkin Dimitry E. , Kolařík Jan , Šoóš Miroslav , Schmuki Patrik
Published: February 2025

g-C3N4 modified with Pd single atoms – decorated by reactive deposition – exhibits remarkable photocatalytic hydrogen production efficiency with a low loading of 0.05 wt%, far outperforming g-C3N4 decorated with Pd nanoparticles.
Construction of crosstalk-free multi-functional phototherapeutic agents
Authors: Dai Lixuan , Li Wenxiu , Zhong Xiaoli , Ren Mingguang , James Tony D. , Lin Weiying
Published: February 2025

Phototherapeutic diagnostics has attracted ever increasing interest due to its substantial promise within conventional cancer therapeutic paradigms.
Reducing MoS2 FET contact resistance by stepped annealing to optimize device performance
Authors: Liu Peng , Lin Xin , Li Zewen , Song Dianyou , Wang Fang , Cheng Yan , Song Sannian , Zhang Kailiang
Published: February 2025

A well-established stepped annealing strategy was applied to MoS2 FET optimization to improve interfacial contact and electrical performance.
Shining light on the ferrous analogue: excited state dynamics of an Fe(ii) hexa-carbene scorpionate complex
Authors: Johnson Catherine E. , Deegbey Mawuli , Ilic Aleksandra , Kaul Nidhi , Prakash Om , Wärnmark Kenneth , Jakubikova Elena , Lomoth Reiner
Published: February 2025

An Fe(ii) complex bearing tris(carbene)borate ligands with imidazol-2-ylidene donors shows marked destabilization of metal centered states by the strongly σ-donating ligands. Yet, its high-energy 3MLCT state is rapidly deactivated via a 3MC state.
PIEZO channels as multimodal mechanotransducers
Authors: Lacroix Jérôme J. , Wijerathne Tharaka D.
Published: February 2025

All living beings experience a wide range of endogenous and exogenous mechanical forces. The ability to detect these forces and rapidly convert them into specific biological signals is essential to a wide range of physiological processes. In vertebrates, these fundamental tasks are predominantly achieved by two related mechanosensitive ion channels called PIEZO1 and PIEZO2. PIEZO channels are thought to sense mechanical forces through flexible transmembrane blade-like domains. Structural studies indeed show that these mechanosensory domains adopt a curved conformation in a resting membrane but become flattened in a membrane under tension, promoting an open state. Yet, recent studies suggest the intriguing possibility that distinct mechanical stimuli activate PIEZO channels through discrete molecular rearrangements of these domains. In addition, biological signals downstream of PIEZO channel activation vary as a function of the mechanical stimulus and of the cellular context. These unique features could explain how PIEZOs confer cells the ability to differentially interpret a complex landscape of mechanical cues.
Lysine acetylation in cyanobacteria: emerging mechanisms and functions
Authors: Liu Xin , Yang Mingkun , Ge Feng , Zhao Jindong
Published: February 2025

Cyanobacteria are ancient and abundant photosynthetic prokaryotes that play crucial roles in global carbon and nitrogen cycles. They exist in a variety of environments and have been used extensively as model organisms for studies of photosynthesis and environmental adaptation. Lysine acetylation (Kac), a widespread and evolutionarily conserved protein posttranslational modification, is reversibly catalyzed by lysine acetyltransferases (KAT) and lysine deacetylases (KDACs). Over the past decade, a growing number of acetylated proteins have been identified in cyanobacteria, and Kac is increasingly recognized as having essential roles in many cellular processes, such as photosynthesis, energy metabolism, and stress responses. Recently, cGNAT2 and CddA were identified as KAT and KDAC in the model cyanobacterium Synechococcus sp. PCC 7002, respectively. The identified Kac regulatory enzymes provide novel insight into the mechanisms that globally regulate photosynthesis in cyanobacteria and potentially other photosynthetic organisms. This review summarizes recent progress in our understanding of the functions and mechanisms of lysine acetylation in Cyanobacteria. The challenges and future perspectives in this field are also discussed.
Dating in Stuttering Therapy: A Framework for Practice
Authors: Johnson Monica L. , Medina Angela M.
Published: February 2025

Purpose:

The focus of this article is to explore the intricacies of dating for people who stutter and integrate this aspect of life into therapy. Furthermore, this article aims to provide a framework for practice from which speech-language pathologists can incorporate the communicative context of dating into the lives of people who stutter on their caseloads.

Method:

We introduce Knapp's (1978) theoretical process of initiation and maintaining intimate relationships and lay out a framework to guide clinicians through incorporating dating into our provision of services for people who stutter.

Conclusions:

This article champions clinicians who enhance their practices by supporting communication for adults who stutter and are interested in beginning or maintaining intimate relationships. We present guidance for clinicians to enhance their practices by providing therapeutic opportunities for determining when and where in their lives people who stutter exercise therapeutic strategies. Overall, the social communicative lives of people who stutter, including dating, are a matter to be addressed by our expertise in the profession's focus on facilitating and supporting successful communication.
Investigating chemical variations between interstellar gas clouds in the solar neighbourhood
Authors: Ramburuth-Hurt T. , De Cia A. , Krogager J.-K. , Ledoux C. , Jenkins E. , Fox A. J. , Konstantopoulou C. , Velichko A. , Dalla Pola L.
Published: February 2025

The interstellar medium (ISM) is a fundamental component of the Milky Way. Studying its chemical composition and the level of its chemical diversity gives us insight into the evolution of the Milky Way and the role of gas in the Galactic environment. In this study we used a novel simulation technique to model the distribution of total hydrogen between gas components and, therefore, derive new constraints on the dust depletion and metallicity. We studied individual gas components along the lines of sight towards eight bright O/B stars within 1.1 kpc of the Sun using high-resolution HST/STIS absorption spectra (R ∼ 114 000). We measured the level of dust depletion for these individual components and find components with higher levels of dust depletion compared to Milky Way sightlines in the literature. We find large ranges in the level of dust depletion among components along lines of sight, up to a factor of 15 (or 1.19 dex). Although it is not possible to directly measure the metallicity of individual components due to the saturated and damped Lyman-α line, we investigated possible metallicity ranges for individual gas components by exploring many different distributions of the total hydrogen gas between components. We selected possible combinations of these gas fractions that produce the minimum metallicity difference between components, and for these cases we determine individual metallicities to accuracies that range between ∼ 0.1 and 0.4 dex. This work shows that full line-of-sight analyses do not capture the level of diversity along lines of sight, and that component-by-component studies give a more in-depth understanding of the chemical intricacies of the ISM.
Intermediate-mass stars and the origin of the gas-giant planet-metallicity correlation
Authors: Maldonado J. , Mirouh G. M. , Mendigutía I. , Montesinos B. , Gragera-Más J. L. , Villaver E.
Published: February 2025

Context. Currently, the number of known planets around intermediate-mass stars (1.5 M⊙ < M⋆ < 3.5 M⊙) is rather low. As a consequence, models of planet formation derive their strongest observational evidence from the chemical signature of mostly low-mass (FGK) main-sequence (MS) stars with planets.

Aims. We aim to test whether the well-known correlation between the metallicity of the star and the presence of gas-giant planets found for MS low-mass stars still holds for intermediate-mass stars. In particular, we aim to understand whether or not the planet-metallicity relation changes as stars evolve from the pre-MS to the red giant branch.

Methods. We compiled the basic stellar parameters (metallicity, mass, and age) of a sample of intermediate-mass stars at different evolutionary phases with and without evidence suggesting that they host gas-giant planets. The metallicities of the different susbsamples were compared and set in the context of current models of planet formation and stellar evolution.

Results. Our results confirm that pre-MS stars with transitional discs with gaps show lower metallicities than pre-MS ones with flat discs. We show a tendency of intermediate-mass stars in the MS to follow the gas-giant planet-metallicity correlation, although the differences in metal content between planet and non-planet hosts are rather modest and the strength of the correlation is significantly lower than for the less massive FGK MS stars. For stars in the red giant branch, we find a strong planet-metallicity correlation, compatible with that found for FGK MS stars. We discuss how the evolution of the mass in the convective zone of the star’s interior might affect the measured metallicity of the star. In particular, if the planet-metallicity correlation were of a primordial origin, one would expect it to be stronger for less massive stars, as they are longer convective during the stellar evolution. However, within our sample, we find the opposite.

Conclusions. The lack of a well-established planet-metallicity correlation in pre-MS and MS intermediate-mass stars can be explained by a scenario in which planet formation leads to an accretion of metal-poor material on the surface of the star. As intermediate-mass stars are mainly radiative, the metallicity of the star does not reflect its bulk composition but the composition of the accreted material. When the star leaves the MS and develops a sizeable convective envelope, a strong-planet metallicity correlation is recovered. Thus, our results are in line with core-accretion models of planet formation and the idea that the planet-metallicity correlation reflects a bulk property of the star.
Analysis of the effect of hydrothermal processing on the technological properties of "Vakhshskaya-116" rye grown in a dry climate
Authors: Zaynobiddinov Muhammad Zaxiriddin , Dodayev Qo’chqor , Ravshanov Suvonqul , Maksumova Dilrabo , Dissanayake Kasun , Rifky Mohamed
Published: February 2025

This research paper presents the results of studying the effect of hydrothermal processing on the technological properties of autumn "Vakhshskaya-116" rye grown in a dry climate. The research was carried out using the general and modern chemical and physico-chemical methods specified in the "Rules for organization and management of technological processes in mills". Hydrothermal treatment of "Vakhshskaya-116" rye grain grown in dry climate showed 14.5-15% moisture, 64.77-64.80% flour yield after 6-8 hours of soaking, and 177-179 units of amylolytic activity (fall number). The results of this experiment confirmed the results presented in Table 1, entitled Effect of hydrothermal treatment on the amylolytic activity of "Vakhshskaya-116" rye grain. During the preparation of autumn "Vakhshskaya-116" variety rye grown in dry climatic conditions for flour weighing, its moisture content is 14.5-15%; 6-8 hours of soaking time has been found to be the most effective.
Increase in protein content by cultivation of fungi "Aspergillus oryzae" and "Pleurotus ostreatus" in fish feeding environment
Authors: Niyozov Khusan , Dodayev Qo’chqor , Rakhmatovna Akhmedova Zahro , Maksumova Dilrabo , Dissanayake Kasun , Rifky Mohamed
Published: February 2025

This paper is devoted to the study of protein synthesis by selected basidiomycete fungi-producers Pleurotus ostreatus and Aspergillus oryzae using microbiological methods with the aim of increasing the amount of protein in feeds during the preparation of balanced, protein-rich compound feeds for fish farming. It was identified that Pleurotus ostreatus and Aspergillus oryzae mushrooms have been shown to increase the amount of protein by 32.18% in 7 days, while Aspergillus oryzae mushrooms have been shown to increase the amount of protein by 168% in 7 days. - by 29.66%. Considering that the fish's need for protein is 30-35%, the fish's need for protein can be met with feeds with an increased protein content of 32.18%. Macroscopic fungi predominantly exhibit protein and enzymatic activity from 5-7 days growth. Since feed products are mainly polysaccharides, the growth and development of microorganisms in them, as well as the production of products, takes a certain period of time
Biologized methods for increasing the productivity of vegetable crops and potatoes in irrigated conditions of the Volgograd region
Authors: Sinebabnova Yulia , Gichenkova Olga , Laptina Yulia , Malikova Polina , Laptin Alexey
Published: February 2025

A regulation for the application of biological and chemical plant protection products in vegetable crop rotation has been developed. Agricultural practices have been proposed that can significantly increase the yield and organoleptic properties of vegetable products. The effect of biopreparations on increasing the productivity of such vegetable crops as carrots, onions, beets and potatoes has been established. This has been especially noticeable in the production of commercial products, where the increase was 3.7 t/ha for carrots, 2.6 t/ha for onions, 9.4 t/ha for potatoes, and 19.5 t/ha for beets. The yield increase on beets was obtained due to the preservation of plants by the time of harvesting when applying biopreparations by 80%, and 15-25% when applying chemicals.
Postpartum therapy of reproductive organs in high-yielding cows after multiple pregnancy
Authors: Shevtsova Alevtina , Kocharyan Valentina , Bakanova Ksenia , Kocharyan Artem , Pereryadkina Svetlana
Published: February 2025

The article presents data on the frequency of twins in dairy cows, an analysis of cases of postpartum pathologies and the results of treatment and preventive measures in an agricultural enterprise in the Volgograd region. The work was carried out in the Limited Liability Company "SP "Donskoye" of the Volgograd region on Holstein cows with a milk productivity of 8,000-10,000 kg. At the first stage of the work, an analysis of the level of multiple pregnancy in cows in the herd was carried out, for this purpose, indicators of zootechnical and veterinary records and reporting for 2022-2023 were used. Ultrasound examination was used to determine twinning in cows. Cows with multiple pregnancy were monitored until parturition. Animals identified with pathologies of the genital organs in the postpartum period of multiple pregnancy, depending on the nature of the pathology, were subjected to treatment. The results of the study of the twinning rate in cows in the agricultural enterprise of the Volgograd region show that the number of twins in the total structure of calvings for the analyzed periods amounted to 4.2-2.4%, respectively. It was found that the level of diseases in the studied cows with uterine subinvolution was 37.2%-24.7%, placenta retention - 22.0%-27.2%, endometritis 34.0%-39.5%, respectively. The effectiveness of 1 treatment regimen for endometritis in the postpartum period in cows was determined. The study of the phenomenon of multiple pregnancy in cattle seems to us to be a promising direction that allows us to develop measures to reduce unfavorable factors during twin pregnancy, as well as to avoid various negative phenomena associated with twinning.
Optimization of cultivation conditions for biosurfactant production by Bacillus mojavensis P1709, Pseudomonas putida PP021, and Pseudomonas fluorescens PCS-20 strains
Authors: Kirichenko Anastasia , Gordeev Alexander , Biktasheva Liliya
Published: February 2025

Biosurfactants, being a promising group of compounds for agriculture, oil production and environmental protection, need further study. Including ways of their production by cultivation of microorganisms obtained from various sources. In this study, the effect of nutrient medium composition on the production of biosurfactants by Bacillus mojavensis P1709, Pseudomonas putida PP021 and Pseudomonas fluorescens PCS-20 strains was investigated. The emulsification index (E24) and surface tension (ST) of culture supernatants were determined to evaluate the surfactant properties of the biosurfactants. BH medium with glucose was found to be optimal for B. mojavensis strain P1709, providing an E24 of 61% and ST of 28.3 mN m-1. For P. putida strain PP021 and P. fluorescens strain PCS-20, the best results were obtained on glycerol-nitrate medium with E24 85% and 80%, and ST 27.5 mN m-1 and 29.4 mN m-1, respectively. Medium with hexane as the sole carbon source showed lower efficiency. Further cultivation of the selected strains on optimal media for 72 hours revealed that minimum ST values were reached by 36 hours for B. mojavensis P1709 (23.96 mN m-1) and P. fluorescens PCS-20 (24.4 mN m-1), and by 72 hours (27.5 mN m-1) for P. putida PP021. Despite reaching the plateau of cell growth, the decrease in ST continued, which may be due to changes in biosurfactant composition.
Ensuring the development of beef cattle breeding in the Ust-Labinsk region of the Krasnodar Territory through meadow grass stands
Authors: Yurin Denis , Bedilo Natalia , Osepchuk Denis , Golovan Valentin , Machneva Nadezhda
Published: February 2025

The purpose of the research was to study the efficiency of using land for the development of beef cattle and sheep breeding in the regions of the Krasnodar Territory. The species eaten in the studied areas make up 75.0-93.8%. In the Ust-Labinsk district of the Krasnodar Territory, all studied areas meet the yield requirements, except No. 4, No. 5 and No. 6. Natural pastures can be effectively used with calculated indicators taking into account the grass yield in 3 cuttings of up to 2 hectares per 1 conventional head of cattle. In the studied area, one conventional head in the summer period (lasting 200 days) requires 2144 EFU, in the winter period (lasting 165 days) - 1602.15 EFU, in total for the year - 3746.15 EFU. To ensure the highest profitability from meat animals in the highly rugged terrain of the studied natural meadows, it is recommended to give preference to Hereford, Aberdeen Angus or Kazakh white-headed breeds of cattle.
Methods for determining Cytochrome P450 reductase in biological fluids of animals
Authors: Ponamarev Vladimir
Published: February 2025

The study provides a literature review of modern methods for determining Cytochrome P450 reductase. The importance of the enzyme in the body is established. It is shown that Cytochrome P450 reductase determination is used in pharmacology and toxicology. Observed that modern approaches to determining Cytochrome P450 reductase include mass spectrometry, chromatography, electrochemical methods. Spectrometry – allows detection of low concentrations of the substance and study of reaction kinetics. Chromatography (gas, liquid, thin-layer chromatography) is used to separate complex mixtures and determine enzyme activity. Electrochemical methods (voltammetry) help to study the redox transitions of the enzyme. It is confirmed that ELISA is a new era for the Cytochrome P450 reductase determination. Gaps in modern knowledge about Cytochrome P450 reductase are also identified.
Study of anti-Müllerian hormone in predicting embryo productivity of donor cows
Authors: Kozitsyna Anna , Nikitin George
Published: February 2025

The study included a study of biochemical parameters at different stages of the productive cycle. Ultrasound images at different stages of the cycle, and during superovulation were analyzed. A high positive correlation was found between AMH, urea, and creatinine levels. A correlation was also found between AMH and calcium, and phosphorus levels. The effect of domestic follicle-stimulating medicine for inducing superovulation was investigated. Criteria for determining cow embryo donors by ultrasound and biochemical analysis were identified. The AMH level did not depend on the phase of the reproductive cycle. This allows using AMH as a universal marker without taking into account the phase. During superovulation, the maximum number of corpora lutea oincided with the AMH level peaks. Disadvantages of domestic follicle-stimulating medicine in comparison with foreign analogue were discovered.
Ultrastructure of the choroid plexus epithelium of the brain
Authors: Prusakov Alexey , Ponamarev Vladimir
Published: February 2025

An electron microscopy of the brain lateral ventricles vascular plexuses of a bull was conducted. It was established that the vascular plexuses are lined with a single-layer epithelium. The study established that epithelial cells of the vascular bodies are secretory cells. The main function of these cells is to secrete cerebrospinal fluid. It was confirmed that these function determines a main features of their ultrastructural organization. These include the presence of a light nuclear matrix and the basal labyrinth. High mitochondrial activity and hyaline structure in the cytoplasm are also observed. This indicates high energy activity of cells, especially in the phase of cerebrospinal fluid secretion. The observed changes in organelles may be associated with pathological conditions (inflammation or ischemia).
Prospects for the use of probiotic dietary supplements in compound feed for young rabbits
Authors: Kurchaeva Elena , Safonov Vladimir , Vostroilov Alexander , Ventsova Inna , Zvyagin Andrey
Published: February 2025

The effectiveness of the feed additive "Enzimsporin", which has probiotic properties, was assessed in the process of fattening young rabbits of the hybrid breed "Hikol" in the industrial conditions of a rabbit breeding complex. The experiment was conducted in 2024 at the Lipetsk Rabbit LLC, where groups of clinically healthy animals were formed, selected at the age of 30 days after separating from female rabbits using the pair-analog method. The control individuals received standard compound feed, while the experimental groups used the same compound feed with the addition of "Enzimsporin" in the amount of 0.6 kg / t and 0.8 kg / t. The results showed a positive effect of the additive on growth and weight characteristics. By the 90th day of the experiment, the rabbits of the third group exceeded their relatives from the control group by 319 g (12.94%), and also exceeded the animals of the second group by 148 g (6.00%). The slaughter weight of carcasses of rabbits of the third group consuming compound feed with the introduction of 0.8 kg of the probiotic preparation "Enzimsporin" per 1 ton of compound feed exceeded this indicator relative to the control group by 264 g or 18.11%. The use of the feed probiotic "Enzimsporin" contributed to the accumulation of crude protein in muscle and a decrease in the mass fraction of fat in carcasses, this was especially clearly seen in the fleshy part of the carcasses of individuals of the 3rd group. As for the ash content, no reliably significant difference was recorded in the carcasses of all groups. Therefore, the use of "Enzimsporin" is a promising direction for increasing the productivity of rabbits in industrial rabbit breeding.
Evaluation of the effectiveness of tank mixtures of soil and foliar herbicides in soybean crops in Primorsky Krai
Authors: Morokhovets Tamara , Morokhovets Vadim , Basai Zoya , Vostrikova Svetlana , Markova Elena
Published: February 2025

The biological activity and economic efficiency of a combination of soil herbicides Zenkor Ultra + Dual Gold and sequential application of tank mixtures of Flex, Fusilade Forte, Eventus and Vidblok Plus preparations on their background were studied in soybean crops in Primorsky Krai of the Russian Federation. The experiments were conducted in 2022 and 2023. It was found that the tank mixture Zenkor Ultra 0.25 l/ha + Dual Gold 0.65 l/ha most effectively suppresses all annual cereal species and Asiatic dayflower. The mixture Zenkor Ultra 0.5 l/ha + Dual Gold 1.5 l/ha, in addition to weed cereals and Asiatic dayflower, also reliably controls common ragweed and common lambsguarter, reducing their wet aboveground weight by 77–99%; less effectively – Asian copperleaf (69–79%). At reduced application rates, the tank mixture of soil preparations was ineffective against these species, but showed a good effect on crested elsholtzia, bunges smartweed, common mugwort and curly dock, which were present in the field in 2023. The application of tank mixtures and combinations of foliar herbicides against the background of soil preparations contributed to increased control of dicotyledonous weed species and ensured an increase in yield by 1.21–2.01 t/ha compared to the control and by 0.67–1.22 t/ha more compared to the seed yield obtained as a result of using only soil preparations.
Review of active methods of biological processing of organic waste
Authors: Smirnova Ekaterina , Ivannikova Regina , Selina Marina , Lunegov Alexander , Savinov Vasiliy
Published: February 2025

We have analysed data from domestic and foreign sources. As a result, it was found that the most effective methods of active biological processing were characterized by a higher rate of bioconversion and the quality of the final product, compared with analogues, due to which they became widespread in the agricultural sector. The results of the analysis of modern bioconversion methods contribute to improving the economic efficiency of waste recycling enterprises. The research was conducted in order to familiarize with the trends in the application and analysis of the features of active methods of biological processing, followed by the identification of the most promising ones. As a result of the assessment in the field of reuse of organic matter, enzymatic and vermicomposting (vermicomposting) methods are the most promising.
The influence of water temperature and the pH on controlled spawning and the hatchability of Cyprinus carpio (Linnaeus, 1758), in the conditions of the Republic of Iraq
Authors: Al-Mamoori Loay Mohammed Mazbin , Lagutkina Lina , Martyanov Alexander , Ali Al-Hilali Hassan
Published: February 2025

Water temperature and pH are considered the most important criteria for aquatic hosts of aquatic organisms, which have a significant impact on the maturation of the gonads, reproduction, growth and vital activity in general, in addition to some other environmental factors. Therefore, this study aims to discover the effect of high water temperature in addition to changing the pH on fertilized eggs, embryo growth, hatching rate and larval survival rate after hatching for 85 days, and to research the ideal water temperature and pH for egg hatching and growth of Cyprinus carp larvae. It was found that the higher the temperature that is above 25°C and the pH that is higher than 7.5 or lower than 7.3, the lower the hatching rate and the higher the larval mortality rate. The experiment showed that the fertilization rate reached 97.81 at an average water temperature of 25°C, a pH level of 7.5 and an average incubation period of 75 hours, while the specific growth rate of larvae on the first day was 8.25% and the survival rate was 96%. Therefore, it is recommended to maintain the water temperature at 22-25°C and pH level at 7.3-7.5 for incubating eggs and raising Cyprinus carp fry.
Modeling of the assortment structure of spruce tree trunks in the Kostroma region, European Russia
Authors: Dubenok Nikolay , Lebedev Aleksandr , Gostev Vladimir , Gosteva Daria
Published: February 2025

The issue of using the equations of the stem taper to develop new standards for the assortment of the forest stands is relevant and is widely presented in local and foreign industry sources. The values of trunk diameters for assortment assessment were determined using the O. Garcia stem taper equation. A method for modeling the assortment structure of spruce tree trunks using the stem taper model is proposed. A comparison of the obtained data with current forest inventory standards showed that the use of the stem taper model made it possible to increase the accuracy of accounting for large commercial timber of the highest height quality class by up to 27%. Adjusting the yield values of large, medium, small wood commodity, volume of firewood and waste will help to rationalize the use of trunks and increase the profitability of forestry in the region. The application of the proposed methodology will help to simplify the procedure for sorting forest resources and reduce the costs of its implementation.
Soil carbon emissions in a temperate mixed forest (Tatarstan, Russia) revisited
Authors: Tishin Denis , Chizhikova Nelly
Published: February 2025

The article presents the results of a study of soil carbon dioxide emissions in a mixed forest within the framework of the Carbon-Povolzhie project (Republic of Tatarstan, Russia), aimed at assessing the carbon budget of the ecosystems of the Middle Volga region (Russia). The work continues the study of soil respiration, which began in 2022. Fifteen measurements were taken from April to November 2023 in five replicates. The average monthly carbon emission during the growing season and pre-winter period was 0.15 g C h/m2. The largest emissions were observed at the warmest month – July. The main driver of soil respiration during daylight hours is topsoil temperature. The contribution of soil moisture to carbon emissions is nonlinear and can be considered minor compared to ambient temperature. 20% soil moisture increases soil CO2 emission.
Existence of optimal controls for stochastic Volterra equations
Authors: Serrano Rafael , Pulido Sergio , Cárdenas Andrés
Published: February 2025

We provide sufficient conditions that guarantee the existence of relaxed optimal controls in the weak formulation of control problems for stochastic Volterra equations (SVEs). Our study can be applied when the kernel appearing in the controlled SVE is singular at zero. The existence of relaxed optimal policies relies on the interaction between integrability hypotheses on the kernel and growth conditions on the running cost functional and the coefficients of the controlled SVEs. Under classical convexity assumptions, we can also deduce the existence of optimal strict controls.
Convergence of particles and tree based scheme for singular FBSDEs
Authors: Chassagneux Jean-Francois , Yang Mohan
Published: February 2025

We study an implementation of the theoretical splitting scheme introduced in [Chassagneux & Yang, 2022] for singular FBSDEs [Carmona & Delarue, 2013] and their associated quasi-linear degenerate PDEs. The fully implementable algorithm is based on particles approximation of the transport operator and tree like approximation of the diffusion operator appearing in the theoretical splitting. We prove the convergence with a rate of our numerical method under some reasonable conditions on the coefficients functions. This validates \emph{a posteriori} some numerical results obtained in \cite{chassagneux2022numerical}.
We conclude the paper with a numerical section presenting various implementations of the algorithm and discussing their efficiency in practice.
Jet-stirred homogeneous isotropic turbulent water tank for bubble and droplet fragmentation
Authors: Beckedorff Leonel , Caridi Giuseppe C. A. , Soldati Alfredo
Published: February 2025

We present a new jet-stirred turbulent water tank designed to produce homogeneous isotropic turbulence, focusing on multiphase flow phenomena. In particular, the facility features a high Taylor-microscale Reynolds number of O(103) that can ensure a large inertial range and is suitable for studying the breakage of droplets and bubbles in line with the Kolmogorov–Hinze theory. The turbulence is created in an octagonal horizontal water tank by two opposing jet arrays, where each jet can release continuous flow with adjustable velocity. The acrylic section design allows optical access for six high-speed cameras to apply time-resolved visualization techniques. Using 3D Lagrangian particle tracking, we provide a complete statistical characterization of the turbulence field: our measurements reveal a maximum turbulence anisotropy of 10% in the center of the water tank with an energy dissipation rate up to ɛ = 0.3 m2 s−3. This high energy dissipation rate is sufficient to trigger the breakage of bubbles and droplets of O(1–10 mm), which falls in the turbulence inertial range. Furthermore, we demonstrate the capability of our imaging system and reconstruction methods for multiphase flow studies with examples of full 3D topology reconstruction coupled with surrounding flow measurements.
Direct observation of strong wave/particle interactions in electron-beam-driven plasma wave bursts
Authors: Enloe C. L. , Tejero E. M. , Crabtree C. E. , Soto-Chavez A. R.
Published: February 2025

We present detailed observations of bursting wave behavior at f≃fpe/2 driven by an electron beam in a laboratory plasma, including high-time-resolution measurements of the wave bursts' interaction with the electron beam. A burst of wave activity is observed when a threshold electron beam density relative to the background plasma density is exceeded. Wave bursts varying in their time duration are observed, but the fundamental structure of the bursts appears to be structures with a symmetric time envelope. Wave bursts with amplitudes large enough to substantially heat the electron beam, disrupt the beam, and eventually trap beam electrons at the phase speed of the waves are observed. These behaviors observed in the laboratory are able to be reproduced via numerical simulations. The laboratory results are applicable to a variety of conditions in space plasmas.
Highly efficient path-integral molecular dynamics simulations with GPUMD using neuroevolution potentials: Case studies on thermal properties of materials
Authors: Ying Penghua , Zhou Wenjiang , Svensson Lucas , Berger Esmée , Fransson Erik , Eriksson Fredrik , Xu Ke , Liang Ting , Xu Jianbin , Song Bai , Chen Shunda , Erhart Paul , Fan Zheyong
Published: February 2025

Path-integral molecular dynamics (PIMD) simulations are crucial for accurately capturing nuclear quantum effects in materials. However, their computational intensity often makes it challenging to address potential finite-size effects. Here, we present a specialized graphics processing units (GPUs) implementation of PIMD methods, including ring-polymer molecular dynamics (RPMD) and thermostatted ring-polymer molecular dynamics (TRPMD), into the open-source Graphics Processing Units Molecular Dynamics (GPUMD) package, combined with highly accurate and efficient machine-learned neuroevolution potential (NEP) models. This approach achieves almost the accuracy of first-principles calculations with the computational efficiency of empirical potentials, enabling large-scale atomistic simulations that incorporate nuclear quantum effects, effectively overcoming finite-size limitations at a relatively affordable computational cost. We validate and demonstrate the efficacy of the combined NEP-PIMD approach by examining various thermal properties of diverse materials, including lithium hydride (LiH), three porous metal–organic frameworks (MOFs), liquid water, and elemental aluminum. For LiH, our NEP-PIMD simulations successfully capture the isotope effect, reproducing the experimentally observed dependence of the lattice parameter on the reduced mass. For MOFs, our results reveal that achieving good agreement with experimental data requires consideration of both nuclear quantum effects and dispersive interactions. For water, our PIMD simulations capture the significant impact of nuclear quantum effects on its microscopic structure. For aluminum, the TRPMD method effectively captures thermal expansion and phonon properties, aligning well with quantum mechanical predictions. This efficient GPU-accelerated NEP-PIMD implementation in the GPUMD package provides an alternative, accessible, accurate, and scalable tool for exploring complex material properties influenced by nuclear quantum effects, with potential applications across a broad range of materials.
Exact factorization method for bound vibrational states: An analytical tool for accurate approximations
Authors: Ceotto Michele
Published: February 2025

The Exact Factorization (XF) method represents an interesting formulation of the Schrödinger equation where subsystem wavefunctions are exactly coupled. Here, I show that the XF method can be employed as an analytical tool to study the quantum vibrational problem of bound systems. In particular, after elaborating suitable XF-based wavefunction Ansätze, the ground-state energy approximated expression for bilinearly and quartically coupled harmonic oscillators is estimated. The XF-based analytical solution is compared with adiabatic and perturbative ones, and it is usually found to be an order of magnitude more accurate than these for estimating the anharmonic and coupling correction part of the ground-state energy. This procedure will possibly increase the numerical stability and accuracy of perturbative or Hartree-product based methods when applied to bound state calculations.
Energy level alignment of confined hole states in InAs1−x−ySbxPy asymmetric double quantum dots for single-photon energy up- and downconversion
Authors: Gambaryan Karen M. , Ernst Owen , Boeck Torsten , Marquardt Oliver
Published: February 2025

We present a combined experimental and theoretical study of uncapped In(As, Sb, P) graded composition laterally coupled asymmetric double quantum dots (DQDs), suited for application in nanodiodes or single-photon nano-optical up- and downconverters in the mid-infrared spectral range. We provide details on the growth process using liquid-phase epitaxy and characterization using atomic-force microscopy and scanning electron microscopy (SEM). We find that most DQDs exhibit asymmetry such that the two quantum dots (QDs) of each pair have different dimensions, giving rise to correspondingly different quantum confinement of hole states localized in each QD. Based on these data, we have performed systematic simulations using an eight-band k·p model to identify the relationship between QD dimensions and the energy difference between corresponding confined hole states in the two QDs. Finally, we have determined the strength of an applied electric field required to energetically align the hole ground states of two QDs of different dimensions in order to facilitate hole tunneling to the next QD for further recombination and single-photon emission with a different wavelength.
Mapping the structural–mechanical landscape of amorphous carbon with ReaxFF molecular dynamics
Authors: Dernov A. , Kowalik M. , van Duin A. C. T. , Dumitrică T.
Published: February 2025

We use ReaxFF molecular dynamics (MD) to investigate the relationship between structural and mechanical properties in bulk and nanostructured amorphous carbon (a-C). The liquid-quench MD method is used to generate isotropic bulk samples with mass densities ranging from 0.96 to 3.29 g/cm3. Structural analysis identifies two types of structures with distinct short- and medium-range order: lower-density sp2-dominated a-C, which is characterized by a bimodal ring-size distribution, and higher-density sp3-dominated tetrahedral amorphous carbon (ta-C), exhibiting a unimodal ring-size distribution. Stress–strain MD simulations and analysis reveal how an atomistic structure impacts elastic properties and post-yield atomic rearrangements. All stretched structures demonstrate elastic isotropy and plasticity driven by a ring-size expansion mechanism reflected in changes in ring statistics. The plastic region is substantially larger in ta-C than in a-C due to the post-yield shift from sp3 to sp2 C dominant bonding. In both a-C and ta-C, ultimate failure occurs when a reactive crack, traversed by long sp chains, forms and propagates predominantly perpendicular to the direction of the applied strain. Oxygen infiltration into the fractured region significantly reduces stress resistance, primarily through the early rupture of long sp chains. MD simulations and analysis are extended to a-C slabs, a-C nanotubes, and partially a-C nanotubes. The latter nanostructure highlights the differences between the elastically isotropic a-C walls, which develop circumferential cracking, and the crystalline walls, which tear along crystallographic directions. These results provide a strong foundation for further computational characterization of a-C materials.
Advancing biohybrid robotics: Innovations in contraction models, control techniques, and applications
Authors: Li Tingyu , Takeuchi Shoji
Published: February 2025

Biohybrid robots have attracted many researchers' attention due to their high flexibility, adaptation ability, and high output efficiency. Under electrical, optical, and neural stimulations, the biohybrid robot can achieve various movements. However, better understanding and more precise control of the biohybrid robot are strongly needed to establish an integrated autonomous robotic system. In this review, we outlined the ongoing techniques aiming for the contraction model and accurate control for the biohybrid robot. Computational modeling tools help to construct the bedrock of the contraction mechanism. Selective control, closed-loop control, and on-board control bring new perspectives to realize accurate control of the biohybrid robot. Additionally, applications of the biohybrid robot are given to indicate the future direction in this field.
Investigation on the characteristics and formation mechanism of backflow in S-shaped region of a reversible pump-turbine
Authors: Zhu Zehui , Gu Qi , Wang Dongrui , Chen Hongxun , Ma Zheng
Published: February 2025

When reversible pump turbines go through the S-shape region, there is some significant backflow regions in the vaneless space, accompanied by severe pressure fluctuation. However, the internal correlation and mutual influence mechanism among pressure fluctuation, turbulent vortex structure, and backflow are still unclear enough in current research. In this work, the backflow characteristics and formation mechanism of pump turbine in the S-shape region are figured out by using computational fluid dynamics methods. The results indicate that the Leading-Edge-Passage-Vortex caused by adverse pressure gradient is dominant in the initial stage of the backflow. In this stage, the interaction between the inflow fluid and the backflow fluid is the main reason causing the high amplitude and wideband pressure fluctuation components in the vaneless space. In the stage of backflow development, the adverse pressure gradient and centrifugal force play dominant roles in different backflow regions, respectively. The rotating stall phenomenon appears in the runner and a significant low-frequency component 0.6fn and 0.3fn∼0.45fn appeared, respectively, in the vaneless space and runner. In the fully developed stage, the backflow is dominated by the centrifugal force of the runner. The backflow region is concentrated in the main flow area of the runner inlet, while the inflow region is pushed out to the upper crown and lower ring. These findings can provide the theoretical supports for improving the stability of pump turbine operating in off-design condition.
Machine learning in molecular biophysics: Protein allostery, multi-level free energy simulations, and lipid phase transitions
Authors: Cui Qiang
Published: February 2025

Machine learning (ML) techniques have been making major impacts on all areas of science and engineering, including biophysics. In this review, we discuss several applications of ML to biophysical problems based on our recent research. The topics include the use of ML techniques to identify hotspot residues in allosteric proteins using deep mutational scanning data and to analyze how mutations of these hotspots perturb co-operativity in the framework of a statistical thermodynamic model, to improve the accuracy of free energy simulations by integrating data from different levels of potential energy functions, and to determine the phase transition temperature of lipid membranes. Through these examples, we illustrate the unique value of ML in extracting patterns or parameters from complex data sets, as well as the remaining limitations. By implementing the ML approaches in the context of physically motivated models or computational frameworks, we are able to gain a deeper mechanistic understanding or better convergence in numerical simulations. We conclude by briefly discussing how the introduced models can be further expanded to tackle more complex problems.
Investigation of critical tunnel length based on the maximum positive pressure on the trailing carriage of a high-speed train
Authors: Xue Xiangdong , Song Yonghong , Zhang Duihong , Ren Shujian , Kang Yang
Published: February 2025

The passage of a high-speed train through a tunnel exposes it to substantial tunnel pressure waves that are heavily affected by the length of the tunnel. Although there are different criteria for determining the critical tunnel length, none of them consider the characteristics of the maximum positive pressure experienced by the trailing carriage, which has been encountered in field tests in China. To address this problem, by dividing the process of train–tunnel interaction into three stages based on their spatial relationship and analyzing the effects of the train wave signature (TWS), four pressure states on the train were summarized. In particular, for the measuring points located on the trailing carriage, a maximum positive pressure can be observed when the pressure state aligns with the state characterized by the TWS reflecting at the tunnel entrance and partially passing through the measuring location. Therefore, the corresponding critical tunnel length was derived based on this time relationship. Its effectiveness was validated using field test data. The current study will provide valuable insights into the aerodynamic behavior of high-speed trains running in tunnels, contribute to the optimization of tunnel design, and ensure the safety and amenity of railway transportation.