87 research outputs found

    COMPARATIVE CHARACTERISTICS OF THE RHYTHM OF THE SEASONAL DEVELOPMENT OF SCUTELLARIA BAICALENSIS GEORGI IN THE NON-CHERNOZEM ZONE AND ON THE SOUTH COAST OF THE CRIMEA

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    Scutellaria baicalensis is a valuable medicinal plant and a protected species of the East Asian flora. Therefore, work on its introduction is underway in many regions of Russian Federation. Studying of the influence of meteorological factors on the phenology of the S. baicalensis in regions of Russian Federation with contrasting climatic conditions is important in grounds of climate change. Materials and methods. The object of the study is the population of the S. baicalensis biocollections of All-Russian Scientific Research Institute of Medicinal and Aromatic Plants and Nikitsky Botanical Garden. Meteorological indicators: sum of active temperatures, sum of precipitation. Statistical analysis: Tau-b-Kendall correlation coefficient. Results. The duration of the growing season in each region has little variability, independently of the weather conditions of the year. The interval between the onset of phenological phases in the Crimea was characterized by weaker variability than in the Non-Chernozem zone. A significantly smaller amount of active temperatures was required for the onset of phenological phases In the Non-Chernozem zone compared to the southern coast of Crimea. The difference in the average sum of active temperatures across the regions reached 1694.6°C by the end of the growing season. The amount of precipitation had sharp fluctuations in both regions and in all years of research. Conclusion. Secondary flowering, wide amplitudes of the duration of phenological phases and the growing season as a whole, the sum of active temperatures and precipitation indicate the ecological plasticity of the S. baicalensis and the availability of conditions for its cultivation in both regions

    RELATIONS FOR CALCULATING THERMODYNAMIC AND TRANSPORT PROPERTIES OF LIQUID LITHIUM

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    The results of the analysis of experimental data from open publications for the period from 1933 to 2018 are presented. The calculated relations for estimating the density,heat ca-pacity,thermal conductivity,dynamic viscosity,surface tension,and electrical resistivity for liquid lithium are proposed

    Investigation of initiation of gigantic jets connecting thunderclouds to the ionosphere

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    The initiation of giant electrical discharges called as "gigantic jets" connecting thunderclouds to the ionosphere is investigated by numerical simulation method in this paper. Using similarity relations, the triggering conditions of streamer formation in laboratory situations are extended to form a criterion of initiation of gigantic jets. The energy source causing a gigantic jet is considered due to the quasi-electrostatic field generated by thunderclouds. The electron dynamics from ionization threshold to streamer initiation are simulated by the Monte Carlo technique. It is found that gigantic jets are initiated at a height of ~18-24 km. This is in agreement with the observations. The method presented in this paper could be also applied to the analysis of the initiation of other discharges such as blue jets and red sprites.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France

    A case of 17-beta-hydroxysteroid dehydrogenase deficiency type 3 in adult endocrinologist practice

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    17β-Hydroxysteroid dehydrogenase 3 deficiency (17HSD3) is a rare autosomal recessive cause of 46, XY disorders of sex development resulting from HSD17B3 gene mutations, in which conversion of androstenedione to testosterone is impared. The clinical signs of 17HSD3 deficiency depend on the residual activity of the enzyme. The diagnosis of 17HSD3 deficiency is based on reduced testosterone/androstenedione ratio (T/AD < 0.8). Patients are usually assigned at birth and raise as female. If the diagnosis is made before puberty, gonadectomy is recommended, taking into account the risk of masculinization during the puberty and estrogen therapy initiation in this period. If the diagnosis of 17HSD3 deficiency is established during puberty, when virilization manifests, the therapeutic strategy is based on the results of comprehensive psychological testing and gender identity of a patient. In patients with more pronounced masculinization or diagnosis established shortly after birth, who are assigned at birth and raise as male, testosterone therapy is used to achieve a male phenotype. The 17HSD3 deficiency and virilization often result in a change of gender identity during puberty. The article presents a clinical case of 17-βhydroxysteroid dehydrogenase type 3 deficiency with late diagnosis due to parental will. The diagnostic approaches and management of the disease are also described

    Positive and negative streamers in ambient air: modeling evolution and velocities

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    We simulate short positive and negative streamers in air at standard temperature and pressure. They evolve in homogeneous electric fields or emerge from needle electrodes with voltages of 10 to 20 kV. The streamer velocity at given streamer length depends only weakly on the initial ionization seed, except in the case of negative streamers in homogeneous fields. We characterize the streamers by length, head radius, head charge and field enhancement. We show that the velocity of positive streamers is mainly determined by their radius and in quantitative agreement with recent experimental results both for radius and velocity. The velocity of negative streamers is dominated by electron drift in the enhanced field; in the low local fields of the present simulations, it is little influenced by photo-ionization. Though negative streamer fronts always move at least with the electron drift velocity in the local field, this drift motion broadens the streamer head, decreases the field enhancement and ultimately leads to slower propagation or even extinction of the negative streamer.Comment: 18 pages, 10 figure

    Apokamps produced by repetitive discharges in air

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    New experimental and computational data on apokamps produced by repetitive discharges in air, including a detailed description of the research techniques used, are presented. It has been shown that plasma bullets–streamers in apokamps at low frequencies could start not only from the bright offshoot but also directly from the discharge channel. The experimental and computational data demonstrate that the visual color of apokamp changes from blue to red as the intensity ratio of the second to the first positive nitrogen system decreases with the decreasing pressure

    Transforming growth factor β1 (TGF-β1) in patients with endocrine ophthalmopathy and Graves’ disease: A predictor of treatment efficiency

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    Current therapeutic approaches to the treatment of endocrine ophthalmopathy (EOP) are based on nonspecific immunosuppression with glucocorticosteroids (GCs) and radiation therapy of the eye orbits. However, some patients exhibit resistance to the treatment. In a previous study, we have detected high levels of soluble cytokine receptors: sTNFα-R1, sTNFα-R2, sIL-2R, and the TGF-β1 cytokine in euthyroid patients with long-lasting non-treated EOP and Graves’ disease (GD). TGF-β1 level was significantly higher in the patients with EOP compared to healthy individuals, and increased with prolonged EOP duration, thus suggesting activation of the factors regulating immune system which promote suppression of the autoimmune process. The aim of this work was to study the dynamics of TGF-β1 and cytokine receptors: sTNFα-R1, sTNFα-R2, sIL-2R in the course of immunosuppressive therapy with high doses of GCs, as possible predictors of treatment efficacy. The study included 49 patients (98 eye orbits) with GD of euthyroid state and subclinical thyrotoxicosis, and the persons with EOP in active phase, who had not previously treatment for EOP. Concentrations of TGF-β1 cytokine, sTNFα-RI and sTNFα-R2, sIL-2R, antibodies to the thyroid-stimulating hormone receptor (rTSH), free fractions of thyroxine (fT4) and triiodothyronine (fT3), TSH in blood serum were determined in blood serum. Ultrasound examination of the thyroid gland (ultrasound of the thyroid gland), multi-layer computed tomography (MSCT)/magnetic resonance imaging (MRI) of the orbits were also performed. The patients were administered immunosuppressive therapy with high doses of HCs (methylprednisolone) in the course of pulse therapy, at a standard dosage of 4500-8000 mg, taking into account the severity and activity of the EOP clinical manifestations. The examination was carried out 3, 6, 12 months after starting the treatment. 3 and 6 months after the GC administration, more than 30% of patients remained resistant to treatment. The levels of TGF-β1 did not change significantly in the patients with positive EOP dynamics. In the patients resistant to GC treatment, the level of TGF-β1 was significantly decreased compared with patients who showed positive clinical dynamics. The level of sNFR1 and sNFaR2 did not change significantly. There were no significant differences in the levels of antibodies to rTSH, thyroid hormones in the patients resistant to GC treatment and with positive dynamics.Immunosuppressive therapy with high-dose of methylprednisolone in pulse therapy regimen showed high efficacy and good tolerability, while some patients remain resistant to treatment. Lower levels of TGF-β1 cytokine at initial time and during the treatment allow usage of TGF-β1 levels as a biomarker of the activity of the process, treatment efficiency, and prognosis of the disease. Activation of TGF-β1, a fibroblast growth factor, may contribute to the development of fibrosis, strabismus, and diplopia
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