8 research outputs found

    Effect of probiotics on height and weight parameters of young cattle

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    The main direction of agriculture is the search for effective methods of production to provide the population with the provision and to ensure the food independence of the Russian Federation. The purpose of this study was to determine the effect of feed yeast produced in Russia and abroad on the growth of calves up to six months of age. The scientific and production experiment was carried out on the dairy farm of "Gigant" Agricultural Production Cooperative Collective Farm of the Stavropol Territory. Four groups of ten heads of black-and-white calves were formed according to the principle of analogues. The animals were ten days old. Together with the main diet the calves of the 1st experimental group received I-SAK1026 drug in the amount of 11 g per animal per day, the animals of the second experimental group were fed with "Levisil SC+" drug in the amount of 5 g per animal per day, and the calves of the third experimental group received "Optisaf" drug in the amount of 15 g per animal per day. Changes of linear measurements of growth rate with age were different. The animals of the third experimental group had an advantage in most of the measurements. Compared to the control, they showed more significant results. Based on the results of the study, the following was established. Calves of the third experimental group that received "Optisaf" probiotic were characterized by more significant activity of metabolic processes. The calves of this group were ahead of the control calves in terms of development and growth

    Ionic high-pressure form of elemental boron

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    Boron is an element of fascinating chemical complexity. Controversies have shrouded this element since its discovery was announced in 1808: the new 'element' turned out to be a compound containing less than 60-70 percent of boron, and it was not until 1909 that 99-percent pure boron was obtained. And although we now know of at least 16 polymorphs, the stable phase of boron is not yet experimentally established even at ambient conditions. Boron's complexities arise from frustration: situated between metals and insulators in the periodic table, boron has only three valence electrons, which would favour metallicity, but they are sufficiently localized that insulating states emerge. However, this subtle balance between metallic and insulating states is easily shifted by pressure, temperature and impurities. Here we report the results of high-pressure experiments and ab initio evolutionary crystal structure predictions that explore the structural stability of boron under pressure and, strikingly, reveal a partially ionic high-pressure boron phase. This new phase is stable between 19 and 89 GPa, can be quenched to ambient conditions, and has a hitherto unknown structure (space group Pnnm, 28 atoms in the unit cell) consisting of icosahedral B12 clusters and B2 pairs in a NaCl-type arrangement. We find that the ionicity of the phase affects its electronic bandgap, infrared adsorption and dielectric constants, and that it arises from the different electronic properties of the B2 pairs and B12 clusters and the resultant charge transfer between them.Comment: Published in Nature 453, 863-867 (2009

    The 2021 room-temperature superconductivity roadmap.

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    Designing materials with advanced functionalities is the main focus of contemporary solid-state physics and chemistry. Research efforts worldwide are funneled into a few high-end goals, one of the oldest, and most fascinating of which is the search for an ambient temperature superconductor (A-SC). The reason is clear: superconductivity at ambient conditions implies being able to handle, measure and access a single, coherent, macroscopic quantum mechanical state without the limitations associated with cryogenics and pressurization. This would not only open exciting avenues for fundamental research, but also pave the road for a wide range of technological applications, affecting strategic areas such as energy conservation and climate change. In this roadmap we have collected contributions from many of the main actors working on superconductivity, and asked them to share their personal viewpoint on the field. The hope is that this article will serve not only as an instantaneous picture of the status of research, but also as a true roadmap defining the main long-term theoretical and experimental challenges that lie ahead. Interestingly, although the current research in superconductor design is dominated by conventional (phonon-mediated) superconductors, there seems to be a widespread consensus that achieving A-SC may require different pairing mechanisms.In memoriam, to Neil Ashcroft, who inspired us all

    Circulation of porcine circovirus type 2 in pigs of different age groups in the Russian Federation

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    The paper deals with the results of assessing the intensity of PCV2 (porcine circovirus type 2) circulation in pigs of different age groups on pig farms in the Russian Federation. Serum samples of 128 pigs of different age groups from two pig farms in the Russian Federation were studied. As a result, specific antibodies to PCV2 were detected that proves virus circulation. Average titer of serum antibodies was 1:2020 for weaning piglets, 40 d.a. (days of age), in prenursery piglets of the age of 20 days - 1:3120; in replacement gilts of the age of 175 days - 1: 5124; in feeding pigs of the age of 180 days - 1:5300. In female pigs, the percentage of seroprevalence was 95 %. With advancing ageing of pigs, the level of antibody titer to PCV2 was increasing that proves the animals were infected after the decrease of colostral antibody level below protective one

    The use of chitosan in the composition of feed “BeeHit” for honey bees

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    Nowadays, chitosan-based biostimulants and their derivatives are being increasingly utilized in veterinary medicine. These substances possess numerous advantageous properties that make them suitable for application in beekeeping. Chitosan and its modified forms are of natural origin and non-toxic, exhibiting immunomodulating properties and antimicrobial activity. They also have the ability to enhance resistance and eliminate heavy metals and toxins from bees' bodies. Chitosan is derived from chitin, a natural component found in the exoskeleton of bees. When acted upon by enzymes like chitinase and chitobiase, chitin and chitosan break down into N-acetyl-D-glucosamine. This characteristic renders chitosan completely biodegradable, ensuring it does not contribute to environmental pollution as it degrades into carbon dioxide (CO2) and water (H2O). Moreover, chitosan boosts bees' resilience against adverse environmental factors and various pathogens. Being naturally biocompatible and biodegradable, chitosan and its derivatives exhibit significant antibacterial, sorbent, fungicidal, and antiviral properties. The aim of the study was to analyze the impact of incorporating chitosan into the composition of “BeeHit” bee feed

    The 2021 Room-Temperature Superconductivity Roadmap

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    Last year, the report of Room-Temperature Superconductivity in high-pressure carbonaceous sulfur hydride marked a major milestone in the history of physics: one of the holy grails of condensed matter research was reached after more than one century of continuing efforts. This long path started with Neil Ashcroft's and Vitaly Ginzburg's visionary insights on high-temperature superconductivity in metallic hydrogen in the 60's and 70's, and has led to the current hydride fever, following the report of high-Tc high-pressure superconductivity in H3S in 2014. This Roadmap collects selected contributions from many of the main actors in this exciting chapter of condensed matter history. Key for the rapid progress of this field has been a new course for materials discovery, where experimental and theoretical discoveries proceed hand in hand. The aim of this Roadmap is not only to offer a snapshot of the current status of superconductor materials research, but also to define the theoretical and experimental obstacles that must be overcome for us to realize fully exploitable room temperature superconductors, and foresee future strategies and research directions. This means improving synthesis techniques, extending first-principles methods for superconductors and structural search algorithms for crystal structure predictions, but also identifying new approaches to material discovery based on artificial intelligence
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