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The hadronic part of the electron structure function F2e has been measured for the first time, using e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of s=91.2–209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.

The advancement of experimental methods has provided new information about the structure and structural fluctuations of water. Despite the appearance of numerous models, which aim to describe a wide range of thermodynamic and electrical characteristics of water, there is a deficit in systemic understanding of structuring in aqueous solutions. A particular challenge is the fact that even pure water is a heterogeneous, multicomponent system composed of molecular and supramolecular structures. The possibility of the existence of such structures and their nature are of fundamental importance for various fields of science. However, great difficulties arise in modeling relatively large supramolecular structures (e.g. extended hydration shells), where the bonds between molecules are characterized by low energy. Generally, such structures may be non-equilibrium but relatively long-lived. Evidently, the short times of water microstructure exchanges do not mean short lifetimes of macrostructures, just as the instability of individual parts does not mean the instability of the entire structure. To explain this paradox, we review the data from experimental and theoretical research. Today, only some of the experimental results on the lifetime of water structures have been confirmed by modeling, so there is not a complete theoretical picture of the structure of water yet. We propose a new hierarchical water macrostructure model to resolve the issue of the stability of water structures. In this model, the structure of water is presented as consisting of many hierarchically related levels (the stratification model). The stratification mechanism is associated with symmetry breaking at the formation of the next level, even with minimal changes in the properties of the previous level. Such a hierarchical relationship can determine the unique physico-chemical properties of water systems and, in the future, provide a complete description of them.

IntroductionThe process of forming selenium nanoparticles with various shapes and structures through laser ablation and fragmentation in various solvents has been explored.MethodsLaser ablation and laser fragmentation techniques were employed using nanosecond Nd:YAG second harmonic laser irradiation in 9 different working fluids, including water. The characteristics of the resulting nanoparticles were assessed using transmission electron microscopy (TEM), dynamic light scattering (DLS), spectroscopy, and X-ray diffraction (XRD) methods.ResultsLaser ablation and subsequent laser fragmentation of some organic solvents, such as ethanol, propanol-2, isobutanol, polyethylene glycol, and diethanolamine, have been found to produce trigonal selenium in the form of elongated nanorods approximately 1 μm long and 200 nm thick, with a well-defined crystal structure. In contrast, the use of deionized water, acetone, glycerol, and benzene as solvents results in the formation of spherical amorphous nanoparticles approximately 100 nm in diameter.DiscussionThe polarity of the solvent molecules has been shown to influence the growth of crystalline selenium nanorods in solution during laser ablation and laser fragmentation. Generally, polar solvents hinder the growth of crystalline nanorods, due to interactions between selenium and solvent molecules. Nonpolar solvents, on the other hand, allow for laser fragmentation to reduce particle size and initiate the epitaxial growth of elongated, crystalline selenium nanorods.

This paper studies the dynamics of the development of laser breakdown plasma in aqueous colloids of dysprosium nanoparticles by analyzing the time patterns of plasma images obtained using a high-speed streak camera. In addition, the distribution of plasma flashes in space and their luminosity were studied, and the amplitude of acoustic signals and the rate of generation of new chemical products were studied depending on the concentration of dysprosium nanoparticles in the colloid. Laser breakdown was initiated by pulsed radiation from a nanosecond Nd:YAG laser. It is shown that the size of the plasma flash, the speed of motion of the plasma–liquid interface, and the lifetime of the plasma flash decrease with an increasing concentration of nanoparticles in the colloid. In this case, the time delay between the beginning of the laser pulse and the moment the plasma flash reaches its maximum intensity increases with increasing concentrations of nanoparticles. Varying the laser fluence in the range from 67 J/cm2 to 134 J/cm2 does not lead to noticeable changes in these parameters, due to the transition of the breakdown plasma to the critical regime. For dysprosium nanoparticles during laser breakdown of colloids, a decrease in the yield of hydrogen peroxide and an increase in the rate of formation of hydroxyl radicals per water molecule, characteristic of nanoparticles of rare earth metals, are observed, which may be due to the participation of nanoparticles and hydrogen peroxide in reactions similar to the Fenton and Haber–Weiss reactions.

Introduction: The process of laser-induced breakdown of amorphous and crystalline selenium nanoparticles (Se NPs) of various shapes during nanosecond laser fragmentation of aqueous colloidal solutions of nanoparticles with different concentrations has been studied.Methods: The methods of studying the characteristics of plasma and acoustic oscillations induced by optical breakdown are applied. The methods of assessing the concentration of hydrogen peroxide and hydroxyl radicals, the amount of long-lived reactive species of protein and 8-oxoguanine are applied.Results: It has been established that in the process of laser fragmentation of selenium nanoparticles at a wavelength of 532 nm, corresponding to the maximum absorption of selenium, the highest probability of breakdown, the number of plasma flashes, their luminosity and the amplitude of acoustic signals are achieved at concentrations of the order of 109 NPs/mL. It has been shown that the use of selenium nanoparticles of various shapes and structures leads to a change in the photoacoustic signal during laser-induced breakdown. When crystalline selenium nanoparticles are irradiated, the intensity of the photoacoustic response during breakdown turns out to be greater (1.5 times for flash luminosity and 3 times for acoustics) than when amorphous particles are irradiated at the same concentration. It has been shown that selenium nanoparticles exhibit significant antioxidant properties. Selenium nanoparticles effectively prevent the formation of reactive oxygen species (ROS) during water radiolysis, eliminate radiation-induced long-lived reactive species of protein, and reduce the radiation-chemical yield of a key marker of oxidative DNA damage - 8-oxoguanine.Discussion: In general, the intensity of processes occurring during laser fragmentation of amorphous and crystalline selenium nanoparticles differs significantly. The antioxidant properties are more pronounced in amorphous selenium nanoparticles compared to crystalline selenium nanoparticles.

New data assimilation technique for turbulent flows is proposed, which allows determination of the turbulent viscosity, velocity and pressure distributions from the experimentally measured temperature fields. Measurements are performed for a round jet of hot air using nonintrusive Background Oriented Schlieren technique. Thus, seedless velocity and pressure measurement is realized, as well as measurement of the turbulent viscosity field without usage of any particular turbulence model. Data assimilation results are shown to be in good agreement with the conventional RANS simulations using the Spalart–Allmaras and k-ɛ turbulence models, if adequate smoothing of the input temperature field is performed and sufficient regularization of the energy equation in regions with uniform temperature is provided.

Introduction: Although nonsteroidal anti-inflammatory drugs (NSAIDs) have a clear therapeutic benefit, they can also have serious side effects. The most serious of these is the ulcerogenic effect, which can result in a decline in the quality of life or even death. This calls for the search for and creation of novel compounds with potent anti-inflammatory properties that do not have adverse effects on the digestive system. The aim of the study was to investigate the anti-inflammatory, analgesic, ulcerogenic and anti-ulcerogenic activities of N-isopropenylimidazole zinc complex derivative. Materials and Methods: Experiments in rats and mice were used to determine the median lethal dose LD50 for N-isopropenylimidazole zinc complex derivative (laboratory name Pilim-1). Experimental models of acute exudative inflammation and chronic proliferative inflammation were used. In the first case, the inflammation was induced by sub-plantar injection of carrageenan and a complete Freund’s adjuvant into the hind paw of rats. In the second case, the inflammation was induced by the implantation of a sterile cotton pellet (“cotton pellet–induced granuloma”) under the skin of rats. Acute and tonic pain, visceral, and somatic deep pain were simulated using the formalin test in rats and the acetic acid-induced writhing test in mice, respectively. The ulcerogenic and anti-ulcerogenic effects of Pilim-1 were studied in rat experiments. Pilim-1 and the reference drugs diclofenac, indomethacin and famotidine were administered intragastrically. Results and Discussion: Pilim-1 showed marked anti-inflammatory and analgesic effects, demonstrated less toxicity than diclofenac and indomethacin, while its activity is comparable to diclofenac and superior to indomethacin. Its therapeutic index is higher than that of indomethacin and diclofenac and, in contrast, it essentially has no ulcerogenic effect and exhibits stronger anti-ulcerogenic activity than famotidine. It appears that the anti-inflammatory, analgesic, and gastroprotective properties of Pilim-1 are largely due to its antioxidant and antihypoxic properties, its inhibitory effects on cyclooxygenase and 5-lipoxygenase, and the presence of imidazole and zinc in its structure, both of which have a wide range of biological activity. Conclusion: Pilim-1 can be recommended for further preclinical studies due to its relatively low (practically absent) ulcerative activity, strong anti-inflammatory, analgesic, and anti-ulcerative effects, greater therapeutic index, and less acute toxicity in comparison with diclofenac and indomethacin.

Abstract Springtails (Collembola) inhabit soils from the Arctic to the Antarctic and comprise an estimated ~32% of all terrestrial arthropods on Earth. Here, we present a global, spatially-explicit database on springtail communities that includes 249,912 occurrences from 44,999 samples and 2,990 sites. These data are mainly raw sample-level records at the species level collected predominantly from private archives of the authors that were quality-controlled and taxonomically-standardised. Despite covering all continents, most of the sample-level data come from the European continent (82.5% of all samples) and represent four habitats: woodlands (57.4%), grasslands (14.0%), agrosystems (13.7%) and scrublands (9.0%). We included sampling by soil layers, and across seasons and years, representing temporal and spatial within-site variation in springtail communities. We also provided data use and sharing guidelines and R code to facilitate the use of the database by other researchers. This data paper describes a static version of the database at the publication date, but the database will be further expanded to include underrepresented regions and linked with trait data.

Micromechanical switches are of significant interest for advanced radio frequency and microwave systems, but their practical implementation is limited by low reliability. Electrodes of a microscopic size develop weak contact force that leads to high and unstable contact resistance. The force is typically increased by using a sophisticated switch design with extended lateral dimensions, although a simple and compact cantilever is more preferable. The paper describes for the first time a comprehensive approach to enhance the force of an electrostatically actuated switch. The strategy is applied to a miniature device based on a 50 µm long cantilever. The contact force is increased from 10 to 112 µN, making the switch strong enough to achieve low and stable contact resistance. The restoring force is also enhanced in order to ensure reliable de-actuation. The growth of forces is accompanied by a reduction in the pull-in voltage. Connecting several cantilevers in parallel and manipulating the number and position of contact bumps additionally improves the force and mechanical stability of the switch. An optimal design contains a triple cantilever with two bumps. It provides 50% higher force per contact compared to the single-cantilever switch at the same pull-in voltage and keeps the advantages of a miniature device. The proposed design strategy may be used for building reliable MEMS switches.

Досліджено модифікуючий вплив трубчастого імпульсного сильнострумового релятивістського електронного пучка на титанову мішень зі сплаву ВТ1-0. Побудовано математичну модель динаміки температурного поля взаємодії пучка з мішенню, відповідно до якої здійснено чисельний аналіз. Встановлено взаємозв’язок між характеристиками мікроструктури і чинниками дії опромінення – абляційних процесів і температурного поля. Розглянуто механізм кратероутворення. Описано внесок продуктів конденсації абляційного викиду на формування структури приповерхневого шару.

В работе рассмотрены особенности воздействия релятивистского импульсного пучка электронов на процессы структурообразования в поверхностном слое промышленных алюминиевых сплавов 1201 и 6111 в режиме предплавления. Показано, что в подобранном режиме предплавления - до макроскопического плавления поверхности в зоне воздействия пучка - осуществляется локальное плавление и последующая кристаллизация отдельных объемов микроструктуры поверхностного слоя сплавов. Предполагается, что появление подобных участков микроструктуры сплавов 1201 и 6111 может быть связано и с плавлением неравновесных эвтектик и с плавлением участков сегрегации легирующих элементов.

Aim. This study was aimed at searching and investigating new substances among phenylethyl derivatives of 3-hydroxypyridine, which exhibit a high actoprotective activity under the conditions of normoxia and acute hypobaric hypoxia.Materials and methods. New compounds of phenylethyl derivatives of 3-hydroxypyridine under the SC code (n = 23) were investigated in comparison with bemethyl and bromantane. The actoprotective activity of new compounds was assessed in experimental animals using a treadmill running test under the conditions of normoxia and acute hypobaric hypoxia. The studied chemical substances and comparative drugs were administered 1 hour prior to exposure of animals to the test. Statistical processing of the obtained experimental results was performed using Microsoft Excel and Statistica for Windows 6.0 software.Results. Among the studied substances, active compounds exhibiting an actoprotective effect have been distinguished. SC-119 chemical substance was revealed, which exceeds the other studied chemicals and bemethyl and bromantane reference actoprotectors in terms of the range of effective doses and actoprotective activity under the conditions of normoxia and acute hypobaric hypoxia.Conclusion. According to the results of the study, the SC-119 compound seems to be a prospective candidate for further research into highly effective actoprotective drugs.

Soil organic matter (SOM) is key to maintaining soil fertility, mitigating climate change, combatting land degradation, and conserving above- and below-ground biodiversity and associated soil processes and ecosystem services. In order to derive management options for maintaining these essential services provided by soils, policy makers depend on robust, predictive models identifying key drivers of SOM dynamics. Existing SOM models and suggested guidelines for future SOM modelling are defined mostly in terms of plant residue quality and input and microbial decomposition, overlooking the significant regulation provided by soil fauna. The fauna controls almost any aspect of organic matter turnover, foremost by regulating the activity and functional composition of soil microorganisms and their physical–chemical connectivity with soil organic matter. We demonstrate a very strong impact of soil animals on carbon turnover, increasing or decreasing it by several dozen percent, sometimes even turning C sinks into C sources or vice versa. This is demonstrated not only for earthworms and other larger invertebrates but also for smaller fauna such as Collembola. We suggest that inclusion of soil animal activities (plant residue consumption and bioturbation altering the formation, depth, hydraulic properties and physical heterogeneity of soils) can fundamentally affect the predictive outcome of SOM models. Understanding direct and indirect impacts of soil fauna on nutrient availability, carbon sequestration, greenhouse gas emissions and plant growth is key to the understanding of SOM dynamics in the context of global carbon cycling models. We argue that explicit consideration of soil fauna is essential to make realistic modelling predictions on SOM dynamics and to detect expected non-linear responses of SOM dynamics to global change. We present a decision framework, to be further developed through the activities of KEYSOM, a European COST Action, for when mechanistic SOM models include soil fauna. The research activities of KEYSOM, such as field experiments and literature reviews, together with dialogue between empiricists and modellers, will inform how this is to be done.

Laboratory experiments on the dispersal of woodlouse Porcellio scaber showed that the possibility to disperse diminished the intensity of intraspecific competition. The decision to disperse from local habitat to another one didn’t depend on the weight of individual. The only category of individuals that tried to avoid dispersal were females carrying eggs. This can be connected with the Brownian way of movement of woodlouse during penetration of surrounding environment or with the arrangement of the experiment in which the costs of dispersal were low.

The substance SS-68 relaxes smooth muscles cells of tracheal rings of guinea pig in vitro. Such effect is selective for β2-adrenergic receptors, and type of this influence depends on method of stimulation on insulated trachea. The duration of effect substance SS-68 is not so long (about 15 min for toning after this exposure in concentration 10-7 M or about 60 min after maximum concentration in compare to super selective β2-adrenomimetic substance indacaterol maleate (the tonus of tracheal rings after washing away the substance SS-68 was not resorted. An amplitude of relaxation smooth-muscle cells on influence of the substance SS-68 in concentration 10-7 M is about 47% of the amplitude of relaxation witch has been maded by indacaterol maleate.