16 research outputs found

    Skeletons of Glass Sponges as a Substrate for Creating Functional Composite Organosilicon Materials

    Get PDF
    The article describes a method of creating a three-dimensional organosilicon composite material based on the glass sponge spicules through a combination of soft etching and controlled mechanical action, non-destroying spicules. When in an alkaline medium, the material of the spicules' outer concentric layers is dissolved and silica passes into solution. After 20 to 30 days in alkaline medium, the silica is in excess and precipitates on organic components, forming a network of 300-500-nm thick organosilicon trabeculae, by which the spicules are fused into a single structure. The resulting composite material contains a mineral component of silica and an organic component. The results indicate that the natural organosilicon material can be reformed as a result of self-assembly into three-dimensional or flat structures

    Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

    Get PDF
    Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≄ II, EF ≀35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

    Enhanced optomechanical interaction in the unbalanced interferometer

    Full text link
    Quantum optomechanical systems enable the study of fundamental questions on quantum nature of massive objects. For that a strong coupling between light and mechanical motion is required, which presents a challenge for massive objects. In particular large interferometric sensors with low frequency oscillators are difficult to bring into quantum regime. Here we propose a modification of the Michelson-Sagnac interferometer, which allows to boost the optomechanical coupling strength. This is done by unbalancing the central beam-splitter of the interferometer, allowing to balance two types of optomechanical coupling present in the system: dissipative and dispersive. We analyse two different configurations, when the optomechanical cavity is formed by the mirror for the laser pump field (power-recycling), and by the mirror for the signal field (signal-recycling). We show that the imbalance of the beam splitter allows to dramatically increase the optical cooling of the test mass motion. We also formulate the conditions for observing quantum radiation-pressure noise and ponderomotive squeezing. Our configuration can serve as the basis for more complex modifications of the interferometer that would utilize the enhanced coupling strength. This will allow to efficiently reach quantum state of large test masses, opening the way to studying fundamental aspects of quantum mechanics and experimental search for quantum gravity.Comment: 12 pages, 6 figure

    Modelling an Optimal Capital Srtucture of the Telecommunication Company

    Full text link
    The article is devoted to the development and approbation of a methodological approach to the modelling of an optimal structure of a joint stock company. The optimal capital structure is defined by the authors as a combination of debt and equity, which maximizes the overall value of the company. The article contains the main conclusions received from different economic researches on the optimization of a capital structure. The authors invented a model of the optimal capital structure that may be used by the joint stock companies in emerging markets with greater risk due to political instability, domestic infrastructure problems, currency volatility and limited equity opportunities. This model is supplemented with corrective indicators of financial risks

    Assessment of Electrospun Pellethane-Based Scaffolds for Vascular Tissue Engineering

    Full text link
    We examined the physicochemical properties and the biocompatibility and hemocompatibility of electrospun 3D matrices produced using polyurethane Pellethane 2363-80A (Pel-80A) blends Pel-80A with gelatin or/and bivalirudin. Two layers of vascular grafts of 1.8 mm in diameter were manufactured and studied for hemocompatibility ex vivo and functioning in the infrarenal position of Wistar rat abdominal aorta in vivo (n = 18). Expanded polytetrafluoroethylene (ePTFE) vascular grafts of similar diameter were implanted as a control (n = 18). Scaffolds produced from Pel-80A with Gel showed high stiffness with a long proportional limit and limited influence of wetting on mechanical characteristics. The electrospun matrices with gelatin have moderate capacity to support cell adhesion and proliferation (~30–47%), whereas vascular grafts with bivalirudin in the inner layer have good hemocompatibility ex vivo. The introduction of bivalirudin into grafts inhibited platelet adhesion and does not lead to a change hemolysis and D-dimers concentration. Study in vivo indicates the advantages of Pel-80A grafts over ePTFE in terms of graft occlusion, calcification level, and blood velocity after 6 months of implantation. The thickness of neointima in Pel-80A–based grafts stabilizes after three months (41.84 ± 20.21 ”m) and does not increase until six months, demonstrating potential for long-term functioning without stenosis and as a suitable candidate for subsequent preclinical studies in large animals

    Magnetization of Manganese Perovskites

    Full text link

    Utilization and recycling of municipal solid waste in a subarctic zone

    Full text link
    Municipal solid waste (MSW) collection and disposal is one of the major problems of urban environment in most countries worldwide today. The problem of utilization of solid waste in the Northern Europe on the Kola Peninsula was raised in this article, where the ground arrangement in a subarctic zone is very special and the weather conditions are severe. The paper main goal is to verify long-term impact of the Mezhdurechie municipal landfill on the atmosphere in Kola Peninsula. The paper also aims to establish the holding actions for recycling and utilization of worn-out tires for mentioned municipal landfill. The ground concentrations of pollutants from the operational sources were presented. The proposed recycling development in this paper has a positive impact on the ecoindustry and ensures environmental safety and municipal economy
    corecore