2,045 research outputs found
Mathematical Modeling Of Horizontal Displacement Of Above-ground Gas Pipelines
The modern geodetic equipment allows observations as soon as possible, providing high accuracy and productivity. Achieving high accuracy of measurement is impossible without taking into account external factors that create influence on an observation object. Therefore, in order to evaluate an influence of thermal displacement on the results of geodetic monitoring a mathematical model of horizontal displacement of above-ground pipelines was theoretically grounded and built. In this paper we used data of experimental studies on the existing pipelines "Soyuz" and "Urengoy - Pomary - Uzhgorod". Above-ground pipeline was considered as a dynamic system "building - environment". Based on the characteristics of dynamic systems the correlation between the factors of thermal influence and horizontal displacement of the pipeline axis was defined.Establishing patterns between input factors and output response of the object can be useful not only for geodetic control, but also for their consideration in the design of new objects. It was investigated that the greatest influence on the accuracy of geodetic observations can create dispersion of high-frequency oscillations caused by daily thermal displacement. The magnitude of displacement exceeds actual measurement error.The article presents the results of calculation of high-frequency oscillations of above-ground gas pipeline.The result made it possible to substantiate the accuracy and methodology of geodetic observations of the horizontal displacement of pipeline axes taking into account an influence of cyclical thermal displacement.Research results were recommended for use in practice for enterprises that serve the main gas pipelines and successfully tested by specialists of PJSC "Ukrtransgaz" (Kharkiv, Ukraine) during the technical state control of aerial pipeline crossing in Ukraine and also can be used to form the relevant regulations
Use of Meldonium in the Treatment of Patients with Coronary Artery Disease and Concomitant Arterial Hypertension
Coronary artery disease (CAD) remains one of the leading causes of mortality and disability in Ukraine. Arterial hypertension (AH) is one of the most common diseases and a leading risk factor for coronary artery disease.The aim of the work is to evaluate the antianginal activity of meldonium in the complex therapy in patients with CAD with stable angina and concomitant AH.Materials and methods. The study included 82 patients with CAD, stable angina pectoris II–III functional class, including 52 patients with concomitant AH stage II. The patients were divided into 2 groups. Patients in group 1 were prescribed meldonium at a dose of 750 mg/d for 2 months in addition to basic therapy for the underlying disease. Patients in group 2 continued basic antianginal, disaggregant, hypolipidemic therapy.Results. The use of meldonium led to a decrease in the frequency of angina attacks and the need for nitroglycerin. From the 1st month of therapy and up to 2 months treatment decreased it consumption by 63 and 82.3 % respectively. Adding meldonium to basic therapy led to a likely reduction in shortness of breath, episodes of palpitations, tinnitus, and headache. In all patients, after the treatment, an increase in exercise tolerance was observed, which was more pronounced in the group where patients were receiving meldonium. In the group of patients receiving meldonium, normalisation of blood pressure was faster and more pronounced.Conclusions. Meldonium has antianginal activity, which is manifested by an increase in the physical tolerance of patients, a decrease in the frequency of angina attacks, the need for sublingual nitroglycerin intake and improvement in the well-being of patients. Additional use of meldonium promotes faster and better normalization of blood pressure. The use of meldonium in the complex therapy of patients with stable angina and concomitant AH allows to increase the effectiveness of traditional antianginal therapy and to improve the quality of life of such patients
Rashba Torque Driven Domain Wall Motion in Magnetic Helices
Manipulation of the domain wall propagation in magnetic wires is a key
practical task for a number of devices including racetrack memory and magnetic
logic. Recently, curvilinear effects emerged as an efficient mean to impact
substantially the statics and dynamics of magnetic textures. Here, we
demonstrate that the curvilinear form of the exchange interaction of a magnetic
helix results in an effective anisotropy term and Dzyaloshinskii--Moriya
interaction with a complete set of Lifshitz invariants for a one-dimensional
system. In contrast to their planar counterparts, the geometrically induced
modifications of the static magnetic texture of the domain walls in magnetic
helices offer unconventional means to control the wall dynamics relying on
spin-orbit Rashba torque. The chiral symmetry breaking due to the
Dzyaloshinskii-Moriya interaction leads to the opposite directions of the
domain wall motion in left- or right-handed helices. Furthermore, for the
magnetic helices, the emergent effective anisotropy term and
Dzyaloshinskii-Moriya interaction can be attributed to the clear geometrical
parameters like curvature and torsion offering intuitive understanding of the
complex curvilinear effects in magnetism
Fluoxetine reduces murine graft-versus-host disease by induction of T cell immunosuppression
Serotonin reuptake inhibitors (SRIs) are widely used drugs in the treatment of depression and anxiety disorders. Although SRIs are generally regarded as safe drugs with relatively few side effects, literature suggests that high concentrations of SRIs may alter immune function. We investigated whether high-dose treatment with fluoxetine was able to suppress acute graft-versus-host disease (GvHD) in a MHC-matched, minor histocompatibility antigen mismatched murine bone marrow transplantation model. We found that high doses fluoxetine induce a significant reduction of clinical symptoms and increase survival of these animals. The amelioration of clinical GvHD was accompanied by a reduced expansion of alloreactive T cells. We further analyzed the direct in vitro effect of six SRIs on the viability and proliferation of human T cells and found an anti-proliferative and pro-apoptotic effect that was significantly larger in activated than in resting T cells. We discuss these results in the light of potential future exploration of SRIs as a novel class of T cell immunosuppressive drugs
Adjunctive quetiapine for serotonin reuptake inhibitor-resistant obsessive-compulsive disorder: A meta-analysis of randomised controlled treatment trials
Small studies have shown positive effects from adding a variety of antipsychotic agents in patients with obsessive–compulsive disorder who are unresponsive to treatment with serotonin reuptake inhibitors. The evidence, however, is contradictory. This paper reports a meta-analysis of existing double-blind randomized placebo-controlled studies looking at the addition of the second-generation antipsychotic quetiapine in such cases. Three studies fulfilled the inclusion criteria. Altogether 102 individuals were subjected to analysis using Review Manager (4.2.7). The results showed evidence of efficacy for adjunctive quetiapine (< 400 mg/day) on the primary efficacy criterion, measured as changes from baseline in total Yale–Brown Obsessive Compulsive Scale scores (P = 0.008), the clinical significance of which was limited by between-study heterogeneity. The mechanism underlying the effect may involve serotonin and/or dopamine neurotransmission
Association between the dopamine D-2 receptor TaqI A2 allele and low activity COMT allele with obsessive-compulsive disorder in males
BACKGROUND: Mounting evidence suggests the involvement of the dopamine system in the pathophysiology of obsessive-compulsive disorder. METHOD: The relationship of the dopamine D(2) receptor (DRD2) TaqI A, and catechol-O-methyl-transferase (COMT) NlaIII High/Low activity polymorphism to obsessive-compulsive disorder (OCD) was examined in a sample of 150 patients and 150 controls. RESULTS: OCD patients did not show significant differences in genotype distribution and allele frequency for polymorphisms investigated relative to controls. However, when the sample was stratified by gender, there was a trend to a significant predominance of the DRD2 A2A2 genotype (p=0.049), and a higher frequency of the DRD2 A2 allele (p=0.020) and low-activity COMT allele (p=0.035) in male OCD patients compared to male controls. In addition, we observed an association of the DRD2 A2A2 genotype in patients with an early onset of disease ( <or=15 years) (p=0.033). CONCLUSIONS: Our findings replicate previous reports and provide support for a potential role of the COMT and DRD2 locus in subgroup of male, early onset patients with OC
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