Stages Of Formation Research Articles

In vitro plaque formation model to unravel biofilm formation dynamics on implant abutment surfaces

ABSTRACT Background Biofilm formation on implant-abutment surfaces can cause inflammatory reactions. Ethical concerns often limit intraoral testing, necessitating preliminary in vitro or animal studies. Here, we propose an in vitro model using human saliva and hypothesize that this model has the potential to closely mimic the dynamics of biofilm formation on implant-abutment material surfaces in vivo. Methods A saliva stock was mixed with modified Brain-Heart-Infusion medium to form biofilms on Titanium-Aluminum-Vanadium (Ti6Al4V) and Yttria-partially Stabilized Zirconia (Y-TZP) discs in 24-well plates. Biofilm analyses included crystal violet staining, intact cell quantification with BactoBox, 16S rRNA gene analysis, and short-chain fatty acids measurement. As a control, discs were worn in maxillary splints by four subjects for four days to induce in vivo biofilm formation. Results After four days, biofilms fully covered Ti6Al4V and Y-TZP discs both in vivo and in vitro, with similar cell viability. There was a 60.31% overlap of genera between in vitro and in vivo biofilms in the early stages, and 41% in the late stages. Ten key oral bacteria, including Streptococcus, Haemophilus, Neisseria, Veillonella, and Porphyromonas, were still detectable in vitro, representing the common stages of oral biofilm formation. Conclusion This in vitro model effectively simulates oral conditions and provides valuable insights into biofilm dynamics.

Chromatography-Based Metabolomics as a Tool in Bioorganic Research of Honey

This review presents the latest research on chromatography-based metabolomics for bioorganic research of honey, considering targeted, suspect, and untargeted metabolomics involving metabolite profiling and metabolite fingerprinting. These approaches give an insight into the metabolic diversity of different honey varieties and reveal different classes of organic compounds in the metabolic profiles, among which, key metabolites such as biomarkers and bioactive compounds can be highlighted. Chromatography-based metabolomics strategies have significantly impacted different aspects of bioorganic research, including primary areas such as botanical origins, honey origin traceability, entomological origins, and honey maturity. Through the use of different tools for complex data analysis, these strategies contribute to the detection, assessment, and/or correlation of different honey parameters and attributes. Bioorganic research is mainly focused on phytochemicals and their transformation, but the chemical changes that can occur during the different stages of honey formation remain a challenge. Furthermore, the latest user- and environmentally friendly sample preparation methods and technologies as well as future perspectives and the role of chromatography-based metabolomic strategies in honey characterization are discussed. The objective of this review is to summarize the latest metabolomics strategies contributing to bioorganic research onf honey, with emphasis on the (i) metabolite analysis by gas and liquid chromatography techniques; (ii) key metabolites in the obtained metabolic profiles; (iii) formation and accumulation of biogenic volatile and non-volatile markers; (iv) sample preparation procedures; (v) data analysis, including software and databases; and (vi) conclusions and future perspectives. For the present review, the literature search strategy was based on the PRISMA guidelines and focused on studies published between 2019 and 2024. This review outlines the importance of metabolomics strategies for potential innovations in characterizing honey and unlocking its full bioorganic potential.

Climate-Smart Drip Irrigation with Fertilizer Coupling Strategies to Improve Tomato Yield, Quality, Resources Use Efficiency and Mitigate Greenhouse Gases Emissions

Background: Integrated water and fertilizer management is important for promoting the sustainable development of agriculture. Climate-smart drip irrigation with fertilizer coupling strategies plays an important role to mitigate greenhouse gas emissions, ensuring food production, and alleviating water scarcity and excessive use of fertilizers. Methods: The greenhouse experiment consists of three drip irrigation treatments which include D1: drip irrigation (100 mm); D2: drip irrigation (200 mm); D3: drip irrigation (300 mm) under three different fertilizer management practices N1: nitrogen level (150 kg N ha−1); N2: nitrogen level (300 kg N ha−1); N3: nitrogen level (450 kg N ha−1). Results: The results showed that significantly improved soil moisture contents, quality and tomato yield, while reduced (38.6%) greenhouse gas intensity (GHGI) under the D3N3 treatment. The D2 and D3 drip irrigation treatments with 450 kg nitrogen ha−1 considerably improved NH4+-N contents, and NO3−-N contents at the fruit formation stage. The improve in net primary productivity (NPP), net ecosystem productivity (NEP), evapotranspiration (ET), and ecosystem crop water productivity (CWPeco) through D3N3 treatment is higher. The D3N3 treatment improved (28.2%) the net global warming potential (GWP), but reduced GHGI, due to improved (18.4%) tomato yield. The D3N3 treatment had significantly greater irrigation water productivity (IWP) (42.8%), total soluble sugar (TSS) (32.9%), vitamin C content (VC) (39.2%), soluble sugar content (SSC) (44.2%), lycopene content (41.3%) and nitrogen use efficiency (NUE) (52.4%), as compared to D1N1 treatment. Conclusions: Therefore, in greenhouse experiments, the D3N3 may be an effective water-saving and fertilizer management approach, which can improve WUE, tomato yield, and quality while reducing the effect of global warming.

Cu isotopes in minerals of the Mikheevskoe gold-copper-porphyry deposit (Southern Urals)

Research subject. Minerals of Cu from the Mikheevskoe gold-copper-porphyry deposit in the Southern Urals. Aim. To obtain preliminary data on the isotopic composition of Сu in minerals of various ore types from the largest porphyry deposit of the Urals followed by their interpretation. Methods. The 65Cu/63Cu isotope ratio values were determined using a multicollector inductively coupled plasma mass spectrometer Neptune Plus at the Research Center “Geoanalytik” (IGG of Ural Branch of the Russian Academy of Sciences). In total, 12 samples of three main technological ore types from this deposit were analyzed. Results. The δ65Cu values in the minerals of sulfide, friable, and oxidized ores ranged from –0.36 to +0.25‰ (chalcopyrite, fahlore), from –0.64 to +0.68‰ (bornite, chalcocite, pyrite), and from –2.14 to +0.30‰ (malachite, azurite), respectively. Conclusions: The absence of wide variations in δ65Cu values indicates the formation of the deposit under the conditions of a limited number of stages of hydrothermal ore formation, associated with the evolution of a single hydrothermal system. The obtained data agree well with the values of δ65Cu in porphyry-type deposits from different regions of the world. The conducted study contributes to the current knowledge on behavior of Cu-isotopes in minerals from ore deposits.

Spatial feasibility prediction of green hydrogen scale-up in China under decarbonization policies: Based on improved diffusion model

Hydrogen production from renewable electrolysis is a suitable transformative technology for driving a cleaner energy mix, mitigating climate change, and achieving sustainable development and has been given the color value definition of "green hydrogen". However, this low-carbon technology is still in its infancy, and the pathways for expanding market supply have not been analyzed. To address the problems of unclear factors influencing the diffusion of green hydrogen technology innovation, unclear technology diffusion laws, and inaccurate predictions of regional green hydrogen production capacity under the goal of decarbonization policy, this work constructs a spatial assessment framework of the feasibility of low-carbon technology development in response to climate change on the basis of the theory of technological innovation systems, the improved technology diffusion model, and the feasibility of climate change spatial concepts to analyze and predict the diffusion law and regional green hydrogen production capacity of hydrogen production by renewable energy under the goal of carbon neutrality. The results of the study on the development of renewable hydrogen technology in China show that it follows the law of diffusion of low-carbon technologies in both the formation and growth stages. The diffusion of green hydrogen technology in the formation stage is slow, and the regional green hydrogen capacity in the near term cannot meet the decarbonization policy target demand in 2030. Before the spatial inflection point of technology diffusion feasibility, the demand-pull of the phase decarbonization policy target dominated the stability and sustainability of the green hydrogen supply market. After the inflection point, the internal growth of technology diffusion plays a key role in market diffusion and ultimately reaches a saturation value under the joint regulation of policy and the market to realize a carbon-neutral target capacity demand in 2060. The uncertainty of diffusion model parameters leads to anomalies in the feasibility space of technology diffusion, and risks such as overcapacity or insufficient demand in some regions may occur. Overall, this work provides a systematic assessment system for analyzing and predicting the pathways and characteristics of expanding renewable hydrogen production in specific regions under decarbonization policy objectives.

The Cap and the Spermatostyle Protecting the Sperm Bundle Have a Similar Origin—Ultrastructural Study of the Spermatogenesis from the Ground Beetle Carabus (Chaetocarabus) lefebvrei Dejean, 1826 (Adephaga Carabidae)

The males of Carabus lefebvrei produce sperm bundles of quite variable size as a consequence of a sexual selection via sperm competition. The ultrastructural features of spermatogenesis of the species and the sequence of events leading to sperm bundle formation along the deferent duct lumen revealed the origin and evolution of the apical structure protecting the sperm bundles. Elongated layers of the electron-dense material of variable size and thickness are visible over the microvilli of the distal deferent duct epithelium. They likely correspond to sections through different levels of discoidal secretions. Then, the sperm present in the duct lumen attach to one side of such elongated secreted structures. Later on, these structures bent to take a cap shape and increase their size and thickness by apposition of additional secretions produced by the proximal deferent duct epithelium. These results reconcile the different opinions about the formation of the structures called the cap and the rod (spermatostyle). In our work, we in fact obtained evidence that both these structures have the same origin, even though at the end of their formation they exhibit a different appearance. The reported results indicate that, differently from the spermatostyle, in the initial stages of cap formation, the sperm adhere only to one side of the cap rather than around the whole structure, as it occurs instead along the spermatostyle rod. Under this aspect, the cap structure is similar to the protection present in the sperm of some whirligig beetle.

Productivity and adaptive properties of different origin potato varieties in the Russia’s Far East south

The paper presents the results of a study on the productivity of potato genotypes of different origin depending on the water availability in soil, including the hydrothermal coefficient of Selyaninov (HTC). The group of mid-season varieties was noted to have the highest productivity (710 g/plant). Waterlogging occurred during the growing period of plants (HTC ≥ 2.5), especially at the stage of tuber formation, negatively affecting productivity. High productivity was observed in the years with relatively favorable weather conditions (2019, 2021, and 2022) when the index of environmental conditions (I) was positive and ranged within +201.63 – +221.35. The average productivity of all the specimens was 950 g/plant. Very low productivity (420–670 g/plant) was observed in 2015–2018, 2020, and 2023 due to waterlogging (I = -99.52 – -269.81). Among the studied specimens, we identified the following varieties that were characterized by not only high productivity (above 900 g/plant) but also high responsiveness to changes in the environmental conditions and stability (average bi = 1.49; S2d·103 = 0.42): early-maturing varieties – Antonina, Bastion, Kolymskii, Krepysh, Matushka, Meteor, Pamyati Kulakova, Udacha, Vitesse, Red Lady, and Red Scarlett; medium-early varieties – Arktika, Briz, Zoya, Kamchatka, Lileya, Charodei, and Gala; mid-season varieties – Ocharovanie, Utro, and Favorit; medium-late and late varieties – Kazachok and Pobeda. The research allowed us to identify potato specimens with high productivity (1040-1480 g/plant), marketability (83.2–92.8%), plasticity (bi = 1.20–1.85), stability (S2d = 0,15–5,77), homeostasis (Hom = 9.51–40.62) and breeding value (Sc = 532.79–852.14) under the conditions of the south of the Russian Far East: early maturing varieties – Bastion, Kolymskii, Krepysh, and Pamyati Kulakova; medium-early varieties – Arktika and Zoya; mid-season variety Alyaska; medium-late and late varieties – Vetraz’ and Pobeda.

Self-consistent N-body simulation of planetesimal-driven migration. I. The trajectories of single planets in the uniform background

Abstract Recent exoplanet observations have revealed a diversity of exoplanetary systems, which suggests the ubiquity of radial planetary migration. One powerful known mechanism of planetary migration is planetesimal-driven migration (PDM), which can let planets undergo significant migration through gravitational scattering with planetesimals. In this series of papers, we present the results of our high-resolution, self-consistent N-body simulations of PDM, in which gravitational interactions among planetesimals, the gas drag, and Type I migration are all taken into account. In this first paper (Paper I), we investigate the migration of a single planet through PDM within the framework of the classical standard disk model (the minimum-mass solar nebula model). Paper I aims to improve our understanding of planetary migration through PDM, addressing previously unexplored aspects of both the gravitational interactions among planetesimals and the interactions with disk gas. Our results show that even small protoplanets can actively migrate through PDM. Such active migration can act as a rapid radial diffusion mechanism for protoplanets and significantly influence the early stages of planetary formation (i.e., during the runaway growth phase). Moreover, a fair fraction of planets migrate outward. This outward migration may offer a potential solution for the “planet migration problem” caused by Type I migration and gives a natural mechanism for outward migration assumed in many recent scenarios for the formation of outer planets.

Investigation of carbon-black emissions of a tractor biofuel diesel

BACKGROUND: On the one hand, a petroleum-based liquid fuel diesel engine is a reliable basis for tractors and self-propelled agricultural machines, and on the other hand, the current trends make us to think about the environmental component of these diesel engines and besides to remember about reasonable use of non-renewable petroleum motor fuel. In order to reduce the anthropogenic impact on natural ecosystems and to assess the smokiness of exhaust gases from a tractor diesel running on ethanol and rapeseed oil, the paper considers the relevant model of the carbon-black formation inside it. AIM: Development of the relevant model of carbon-black emission in a tractor diesel running on ethanol and rapeseed oil to assess the smokiness of exhaust gases and to reduce anthropogenic impact on natural ecosystems. METHODS: To simulate the processes of formation and burnout of carbon-black particles in a tractor diesel engine, the volume of the combustion chamber was conditionally divided into several areas (soot content indicators in different areas were added up), and the cycle of calculating the exhaust gas smokiness level included several stages (determination of pressure, integral and differential characteristics of heat dissipation, average temperature of the working fluid, fuel supply indicators and fuel evaporation rate, local coefficients of excess air, composition of gases, concentration of decomposition and oxidation products of rapeseed oil and ethanol, the number of carbon-black particles, the mass of dispersed carbon, the rate of transition of particles to the burnout zone). RESULTS: The developed mathematical model is capable of calculating the carbon-black concentration and the main components of the gas mixture in the reaction zone of the combustion chamber, the content of carbon-black in the exhaust gases at various speed and load modes of operation of a tractor diesel engine. It is capable of obtaining valuable information about the dynamics of the main stages of carbon-black formation and burnout in the cylinder of a tractor diesel engine running on ethanol and rapeseed oil. The results of numerical simulation of carbon-black formation and burnout in a tractor diesel cylinder when running on diesel fuel, ethanol and rapeseed oil are obtained and presented. CONCLUSION: Based on the developed relevant model of carbon-black emission in a tractor diesel engine running on ethanol and rapeseed oil, an assessment of its exhaust gas smokiness was carried out, clearly showing a decrease by 3.4–3.8 times in comparison with diesel fuel operation. The presented method for calculating the carbon-black emission of tractor diesel can be used in the multi-area modeling and researches of such in-cylinder processes as heat generation, heat transfer, etc. The accuracy of calculations based on the proposed model is characterized by the perfection of mathematical algorithms describing the rate of fuel evaporation, the development of a fuel flare, the determination of local temperatures, the rate of flame propagation, the local composition of gases in the cylinder, etc.

The effects of mindfulness and psychological capital on reducing worker stress and promoting health

This cross-sectional study aims to test the combined effect of mindfulness and psychological capital on reducing stress and burnout and improving the perception of health (physical and psychological). The sample consisted of 398 workers (94.5% female) from a public organization in Puerto Rico dedicated to providing services to families and their children in their early formative stages. The results from moderated regressions showed that the interaction between mindfulness and psychological capital was significant, indicating that individuals with high levels of mindfulness and psychological capital showed lower burnout and stress and a higher perception of psychological health. These results suggest that mindfulness provides the conditions to foster the mobilization of personal resources (i.e., psychological capital) to deal with stressful situations and take actions toward greater well-being. Future intervention strategies should consider combining various personal resources to increase their effectiveness in reducing stress and promoting well-being.

Biofilm Formation in Clinical Isolates of Fusarium

Many microbial pathogens form biofilms, assemblages of polymeric compounds that play a crucial role in establishing infections. The biofilms of Fusarium species also contribute to high antifungal resistance. Using our collection of 29 clinical Fusarium isolates, we focused on characterizing differences in thermotolerance, anaerobic growth, and biofilm formation across four Fusarium species complexes commonly found in clinical settings. We investigated the role of carbon sources, temperature, and fungal morphology on biofilm development. Using fluorescence microscopy, we followed the stages of biofilm formation. Biofilms were screened for sensitivity/resistance to the antifungals voriconazole (VOR), amphotericin B (AmB), and 5-fluorocytosine (5-FC). Our findings revealed generally poor thermotolerance and growth under anaerobic conditions across all Fusarium species. VOR was more effective than AmB in controlling biofilm formation, but the combination of VOR, AmB, and 5-FC significantly reduced biofilm formation across all species. Additionally, Fusarium biofilm formation varied under non-glucose carbon sources, highlighting the species’ adaptability to different nutrient environments. Notably, early stage biofilms were primarily composed of lipids, while polysaccharides became dominant in late-stage biofilms, suggesting a dynamic shift in biofilm composition over time.

Optimizing Bt Cotton Yields with Canopy Management in Rainfed Environments

Cotton, the ‘White gold’ is an important commercial crop in India and central India in particular. Sustainable yield can be achieved by increasing plant density and canopy management. Hence an experiment was conducted at Cotton Research Station, Nanded, (Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, M.S., India) during kharif 2023 on medium black cotton soil in randomized block design. The field trail was conducted with three replications and seven treatments viz.,T1 : Cotton in HDPS - 90 x 30 cm (37,037 plants ha-1), T2 : HDPS + De-topping at 90 DAS, T3 : HDPS + De-topping at 75 DAS, T4 : HDPS + Pruning of monopodia at square formation stage, T5 : HDPS + Pruning of monopodia at square formation stage and de-topping at 75 DAS, T6 : HDPS + two sprays of Mepiquat chloride @ 25 g a.i. at square formation followed by 15 days and T7: HDPS + Polymulch + pruning of monopodia at square formation stage and de-topping at 75 DAS. The results showed that growing of cotton with polythene mulch along with pruning of monopodia at square formation stage and de-topping at 75 DAS treatment recorded highest plant height (109.80 cm), no. of sympodia plant-1 (16.53), leaf area (58.16 dm2 and 109.99 dm2 at 60 and 90 DAS, respectively), leaf area index at 120 DAS (0.2107), seed cotton yield (2734 kg ha-1) and GMR (` 1,87,767 ha-1) as compared to all other treatments. Seed cotton yield was increased by 48.66 per cent, significantly over HDPS planting (90 x 30 cm spacing). While treatment HDPS + pruning of monopodia at square formation stage and de-topping at 75 DAS recorded highest NMR (` 48,896 ha-1) and HDPS + de-topping at 90 DAS recorded highest B:C ratio (1.60) as compared to all other treatments respectively. Treatment HDPS + poly mulch + pruning of monopodia and de-topping recorded highest labour requirement per hectare (112.8 man days) as well as seed cotton yield per labour unit (24.24 kg). Thus, adoption of canopy management practice viz., poly mulch, monopodia pruning, de-topping or use f PGR can improve seed cotton yield with high density planting in rainfed areas where it is very low.

Molecular investigation of bamboo during stress relaxation using custom-built mechanical loading platform coupled with Raman spectroscopy

Bamboo holds significant potential as a substitute for plastics. Stress relaxation is a critical property during the fixation stage of plastic formation for bamboo products intended to replace plastic. However, research on this topic has been limited. In this study, a custom-built mechanical loading platform coupled with Raman spectroscopy was acquired during stress relaxation of bamboo under different humidity levels. Results reveal variations in stress relaxation patterns based on node position, radial location, and humidity, along with changes in cellulose molecules in response to these factors. Specifically, stress relaxation modulus in bamboo decreases from the outer to the inner part, increases in the presence of node structures, and decreases with increasing humidity. The shifts in Raman spectral bands exhibit significant changes in response to variations in stress and humidity. The elongation of cellulose chain bands at 1097 cm−1 in the Raman spectrum shows an increasing trend during stress relaxation, with larger band shifts observed at lower humidity. Simulations of cellulose molecular stretching show a stronger stress response at lower moisture content, with a maximum stress of 0.85 GPa for cellulose at 3.3 % moisture content, compared to 0.79 GPa at 7.8 % moisture content. These findings suggest a novel approach for the molecular investigation of materials during stress relaxation, which is crucial for the plasticity processing of bamboo.

The Molecular Cloud Life Cycle. II. Formation and Destruction of Molecular Clouds Diagnosed via H2 Fluorescent Emission

Molecular hydrogen (H2) formation and dissociation are key processes that drive the gas life cycle in galaxies. Using the SImulating the LifeCycle of Molecular Clouds zoom-in simulation suite, we explore the utility of future observations of H2 dissociation and formation for tracking the life cycle of molecular clouds. The simulations used in this work include nonequilibrium H2 formation, stellar radiation, sink particles, and turbulence. We find that at early times in the cloud evolution H2 formation rapidly outpaces dissociation and molecular clouds build their mass from the atomic reservoir in their environment. Rapid H2 formation is also associated with a higher early star formation rate. For the clouds studied here, H2 is strongly out of chemical equilibrium during the early stages of cloud formation but settles into a bursty chemical steady state about 2 Myr after the first stars form. At the latest stage of cloud evolution, dissociation outweighs formation and the clouds enter a dispersal phase. We discuss how theories of the molecular cloud life cycle and star formation efficiency may be distinguished with observational measurements of H2 fluorescence with a space-based high-resolution far-UV spectrometer, such as the proposed Hyperion and Eos NASA Explorer missions. Such missions would enable measurements of the H2 dissociation and formation rates, which we demonstrate can be connected to different phases in a molecular cloud’s star-forming life, including cloud building, rapidly star forming, H2 chemical equilibrium, and cloud destruction.

Unveiling the shape: A multi-wavelength analysis of the galaxy clusters Abell 76 and Abell 1307

We analyse the dynamical state of the galaxy clusters Abell 76 and Abell 1307 from the optical point of view, presenting a coherent scenario that responds to the X-ray emissions observed in these structures. Our study is based on 231 and 164 spectroscopic redshifts, for the clusters A76 and A1307, respectively, obtained mostly with the Telescopio Nazionale Galileo, and complemented with others collected from the SDSS DR16 spectroscopic database and the literature. We find that A76 and A1307 are two galaxy clusters at z = 0.0390 and 0.0815, respectively, with a velocity dispersion of 650 ± 56 km s−1 and 863 ± 85 km s−1, and they show velocity distributions following, in practice, Gaussian profiles. From our dynamical analysis, X-ray studies and SZ-Planck emission, we obtain a mean total mass M500 = 1.7 ± 0.6 ⋅ 1014 M⊙ and 3.5 ± 1.3 ⋅ 1014 M⊙ for A76 and A1307, respectively. Using the SDSS DR16 photometric database, we find that the spatial distribution of likely cluster members in the case of A76 is very anisotropic, while A1307 shows a compact distribution of galaxies, but it is double peaked and elongated in the south-north direction. Using XMM-Newton X-ray data, we compared the surface brightness maps with galaxy distributions and noticed that both distributions are correlated. We reconstructed the total mass profile and velocity anisotropy of both clusters by analysing the full projected phase space, through the MG-MAMPOSSt code. Our study reveals a slight indication of radial orbits for A76, while A1307 seems to prefer more isotropic orbits in the whole cluster range. In summary, A76 represents a typical young cluster, in an early stage of formation, with a very low X-ray surface brightness but a high temperature showing a very anisotropic galaxy distribution. A1307 is however more consolidated and massive showing in-homogeneous galaxy distribution and an asymmetric X-ray emission, which suggest a scenario characterised by recent minor mergers.

Покращення рухової активності в учнів 5 класів засобами рухливих ігор

The purpose of the work is to substantiate theoretically and verify experimentally the effectiveness of the method for improving 5th grade students’ motor activity by means of mobile games. Material and methods. The pedagogical experiment was carried out on the basis of the Krolevets Lyceum No. 1 of the Krolevets City Council of the Sumy Region. It enrolled 32 students of 5th grade from the main medical group. They were divided into a control group (CG, n=16, 5-A grade) and an experimental group (EG, n=16, 5-B grade). The term of the pedagogical experiment was September-November, 2023. Pupils of CG and EG studied according to the Model curriculum "Physical culture. 5-6 grades" for institutions of general secondary education. During Physical Education lessons in the CG, the teacher followed the planned tasks and work plan. A developed method of improving motor activity by means of mobile games was implemented in EG. Research methods: theoretical analysis of scientific and methodical literature, pedagogical experiment. The level of motor activity was determined on the basis of a set of indicators: the time of students’ motor activity with a reflection of its content and quality at different moments of the regime, which was determined with the method of individual timing; the amount of motor activity using the pedometry method for quantitative assessment of motor activity; the intensity of motor activity by the pulsometry method (calculation of heart rate in bpm) when various types of muscle activity were performed; methods of mathematical statistics. The results. At the ascertaining stage of the pedagogical experiment, the following indicators of the 5th grade students’ motor activity level were obtained: in CG, 3 students (19%) had a high level, 7 students (44%) had an average level, and 6 students (37%) had a low level. In EG, 3 students (19%) had a high level, 6 students (37%) had an average level, and 7 students (44%) had a low level. It is necessary to note that the indicators of CG and EG were at the same level. At the formative stage of the pedagogical experiment, a method for improving the motor activity of 5th grade students by means of mobile games was developed and implemented. The developed method was implemented into all forms of physical culture and health work in institution of general secondary education. Its content included mobile games directly during Physical Education lessons and during other forms. The developed method was implemented in three directions, in particular with students, teachers and parents. At the control stage of the pedagogical experiment, the following indicators were obtained: in CG, 4 students (25%) had a high level of motor activity, 7 students (44%) had an average level, and 5 students (31%) had a low level. In EG, 6 students (38%) had a high level of motor activity, 7 students (44%) had an average level, 3 students (18%) had a low level. Thus, in CG there is a significant percentage of 5th grade students who have a low level of motor activity, while in EG there are high and average levels of motor activity among 5th grade students. This fact proves the effectiveness of developed method for improving 5th grade students’ motor activity by means of mobile games. Conclusions. The method we had developed for improving 5th grade students’ motor activity by means of mobile games confirmed its effectiveness during the experimental test and can be recommended for use in the practical activities of a Physical Education teacher.

Realizing single-layer graphene by simultaneous crystallization and top-down etching of amorphous graphene-like carbon obtained via CVD

Continuous large-area graphene can be obtained on copper by utilizing solid polymer carbon sources (SPCS). However, the detailed conversion process and related mechanisms have been rarely reported. Here, a low-temperature chemical vapor deposition (CVD) combined with high-temperature hydrogen annealing (HTHA) method is designed to investigate the intricate evolution process from SPCS to amorphous graphene-like carbon (AGLC), and subsequently to single-layer graphene (SLG). During low-temperature CVD process, under catalysis of copper and auxiliary catalysis of hydrogen, the pyrolysis products of SPCS undergo nucleation and growth on copper, resulting in the formation of AGLC at 500 °C. During subsequent HTHA process above 1000 °C, the conversion of AGLC to continuous SLG can be achieved through simultaneous catalytic crystallization of copper and top-down etching of hydrogen, which sequentially undergoes coexistence stage of AGLC/few-layer graphene (FLG), followed by FLG formation stage. Under different stage and conditions, there exists a synergistic-competitive relationship between catalytic effect of copper and etching effect of hydrogen. The proposed conversion mechanism can provide fundamental insights into SLG synthesis via SPCS, which could facilitate further advancements in large-scale industrial applications of graphene.

Формування фізичної готовності до школи у дітей старшого дошкільного віку засобом спортивних ігор

An analysis of studies on the problem of forming physical readiness for school in older preschool children has been conducted. It is emphasized that physical readiness is fundamental for a child's successful adaptation to the school environment. It includes the development of motor skills, coordination, endurance, and strength, which are crucial for a child’s ability to perform various school tasks, from writing letters to participating in active games during breaks. Insufficient physical preparedness can lead to difficulties in mastering the school curriculum, decreased attention span, quick fatigue, and even health problems. Therefore, it is essential to develop the necessary physical qualities in children before they start school. It has been established that sports games are an effective tool for ensuring the physical readiness of older preschoolers for school. Games help develop coordination, strength, endurance, and flexibility, which are important for comprehensive physical development. The aim of the study is to determine the impact of sports games on the formation of physical readiness for school in older preschool children. At the initial stage of the study, generalized results of the level of physical readiness for school revealed that only 20% of children in the experimental group (EG) and 16% in the control group (CG) showed a high level of readiness, 58% of children in the EG and 52% in the CG showed a medium level, and 22% of children in the EG and 31% in the CG showed a low level. It was noted that the initial level of physical readiness for school in children from both the experimental and control groups was approximately the same at the beginning of the formative stage of the study. During the research, a system was developed and tested, aimed at enhancing the level of physical readiness for school in older preschool children, with active use of sports games elements. The proposed system of work involved organizing activities with children through play and was implemented sequentially across three interrelated stages: introductory, active, and creative. By the end of the study, the results in the CG and EG were as follows: a high level of physical readiness was shown by 46% of children in the EG and 24% in the CG, a medium level by 42% in the EG and 52% in the CG, and a low level by 12% in the EG and 24% in the CG.

Tuning Reaction Kinetics of Fluorinated Molecules to Construct Robust Solid Electrolyte Interphases on SiOx Anode.

Introducing fluorinated electrolyte additives to construct LiF-rich solid-electrolyte interphase (SEI) on Si-based anodes is proven an effective strategy for coping with its massive volume changes during cycling. However, most current research on fluorine-containing additives focuses on their thermodynamics of decomposition, lacking studies on the correlation between the molecular structure of additives and their decomposition kinetics. Herein, two fluorinated ester additives, diethyl fluoromalonate (F1DEM) and diethyl 2,2-difluoromalonate (F2DEM) were designed and synthesized. Through combining a wealth of characterizations and simulations, it is revealed that despite the similar reduction thermodynamics, the favorable reduction kinetics of single-fluorinated F1DEM facilitate a LiF-rich layer during the early stage of SEI formation, contributing to the formation of a more robust SEI on SiOx anode compared to the difluorinated F2DEM. Consequently, the proposed additive achieves excellent cycling stability (84 % capacity retention after 1000 cycles) for 5 Ah 21700 cylindrical batteries under practical testing conditions. By unveiling the role of reaction kinetics, a long-overlooked aspect for the study of electrolyte additives, this work sheds light on how to construct a stable SEI on Si-based anodes.

Tuning Reaction Kinetics of Fluorinated Molecules to Construct Robust Solid Electrolyte Interphases on SiOx Anode

AbstractIntroducing fluorinated electrolyte additives to construct LiF‐rich solid‐electrolyte interphase (SEI) on Si‐based anodes is proven an effective strategy for coping with its massive volume changes during cycling. However, most current research on fluorine‐containing additives focuses on their thermodynamics of decomposition, lacking studies on the correlation between the molecular structure of additives and their decomposition kinetics. Herein, two fluorinated ester additives, diethyl fluoromalonate (F1DEM) and diethyl 2,2‐difluoromalonate (F2DEM) were designed and synthesized. Through combining a wealth of characterizations and simulations, it is revealed that despite the similar reduction thermodynamics, the favorable reduction kinetics of single‐fluorinated F1DEM facilitate a LiF‐rich layer during the early stage of SEI formation, contributing to the formation of a more robust SEI on SiOx anode compared to the difluorinated F2DEM. Consequently, the proposed additive achieves excellent cycling stability (84 % capacity retention after 1000 cycles) for 5 Ah 21700 cylindrical batteries under practical testing conditions. By unveiling the role of reaction kinetics, a long‐overlooked aspect for the study of electrolyte additives, this work sheds light on how to construct a stable SEI on Si‐based anodes.