65 research outputs found
Development trends of diversified agro-industrial enterprises in the context of international integration of economic relations
Globalization and growing competition have exacerbated the problems of analysis and diagnosing the level of economic development sustainability and the possibilities of economic entity market potential use at the global level. The development of a complete, reliable and up-to-date information base on the current financial, economic and technical level of an industrial enterprise development, its strategic development opportunities, making informed effective decisions on the directions of diversification or agro-industrial production restructuring is extremely important today from the standpoint of state policy development regarding the support for the key sectors of the Russian agro-industrial complex.In modern conditions, characterized by the intensification of economic relation integration in international markets
The Nuclear Spin Nanomagnet
Linearly polarized light tuned slightly below the optical transition of the
negatively charged exciton (trion) in a single quantum dot causes the
spontaneous nuclear spin polarization (self-polarization) at a level close to
100%. The effective magnetic field of spin-polarized nuclei brings the optical
transition energy into resonance with photon energy. The resonantly enhanced
Overhauser effect sustains the stability of the nuclear self-polarization even
in the absence of spin polarization of the quantum dot electron. As a result
the optically selected single quantum dot represents a tiny magnet with the
ferromagnetic ordering of nuclear spins - the nuclear spin nanomagnet.Comment: 19 pages, including 3 figures. Short version has been accepted for
publication in Physical Review Letter
Petro- and paleomagnetic studies of basalts of the upper devonian appainskaya suite (Western Yakutia)
Introduction. One of the main tasks of paleomagnetic studies is to obtain a framework of reference poles for calculating the kinematic characteristics of lithospheric taxones as a basis for geodynamic reconstructions. Each paleomagnetic reference point must have a precise (±10 Ma) geochronological dating and a maximum paleomagnetic reliability index. A correct paleomagnetic pole (PMP) can be obtained from the data of geochronological and paleomagnetic studies conducted in one and the same geological object, such as a suite, an intrusive complex etc. In the Yakutian diamondiferous province (YDP), such objects include basalt nappes of the Upper Devonian Appainskaya suite, which stratigraphic position is undoubted (Fran, 385-375 Ma). Geological setting (in brief). In the eastern segments of the Siberian platform, a powerful cycle of tectonic and magmatic activity in the Middle Paleozoic produced transgressive and sheet intrusions, volcanic pipes, lava and tuff formations comprised of basites, as well as all the currently known industrial diamondiferous kimberlite bodies. Magmatic activity of basites was associated with formation of paleorift systems, including the largest one, Viluyi paleorift (Fig. 1). In the Middle Paleozoic, the geodynamic setting for magmatism and rifting was determined by the plume-lithosphere interaction. The rise of the plume's matter underneath the thinned lithosphere was accompanied by decompression melting and formation of basaltic magmas in large volumes. We have studied basalts of the Appainskaya suite which were sampled from the Ygyatta and Markha river valleys (Fig. 2). In the coastal outcrops at the Ygyatta river, two nappes are observed, a (stratigraphically) lower outcrop 17÷23/10 containing plagiophyre palagonite basalts (upper five meters are outcropped), and an upper outcrop 16/10 containing olivinophyric palagonite basalts (upper three meters are outcropped). In the coastal outcrops of the Markha river, from the Enerdek loop to the M. Dyukteli river (outcrop 16÷20/14), only plagiophyric basalts of the lower nappe are developed. At this location, the total capacity of the basalts can reach 35-40 m. In view of the fact that the basalts lie subhorizontally at angles up to 5° (outcrop 17/14, Fig. 3), oriented samples were taken in the modern system of coordinates. Formational features of the chemical composition typical of the Middle Paleozoic intrusive basites (higher contents of Ti, Fe and K) are less clear in derivatives of the effusive facies. By their chemical composition, the basalts are normal alkalinity rocks (the sum of alkali not higher than 3.05 %; SiO2=48.1-49.7 %; rather moderate content of TiO2=1.9-2.5 %) (Fig. 4 A, B). The amount of magnesia (Mg#) ranges from 46 to 56. The main carriers of natural remanent magnetization (NRM, In) are titanomagnetites that belong to titanomagnetite and hemo-ilmenite series (Fig. 4). Research. Our research was conducted in specialized laboratories using modern equipment and facilities of Geo- Scientific Research Enterprise (NIGP) PJSC ALROSA (Mirny), Institute of the Earth's Crust SB RAS (Irkutsk), Kazan Federal University (Kazan) and Institute of Geology of Diamond and Precious Metals SB RAS (Yakutsk). Research results. By magnetic (scalar and vector) parameters, basalts of the Appainskaya suite are characterized by the bimodal distribution of magnetic susceptibility values, NRM and æ: geometric means are 810·10-5 Si-units and 225·10-3 A/m, respectively, at the Ygyatta river, and 1470·10-5 SI-units and 490·10-3 A/m, respectively, at the Markha river (Table 1, Fig. 5). Factor Q is below 1. Results of the petrophysical observations are consistent with the geological materials and suggest that the basalts at the Ygyatta river occupy the upper stratigraphic horizon. The studied outcrops of basalts of the Appainskaya suite have the following characteristic components of Inch: 1. Component A - negative vectors of the characteristic NRM are clustered in the fourth sector of the stereogram (sample Igy179m1, Fig. 10, Fig. 14 A, Table 2). Found in outcrop 16/10. Component A is metachronic Inm that formed due to heating of basalts by dolerites of the Ygyatta sill, which suggests the dyke-type of the anisotropy of magnetic susceptibility (AMS) (Fig. 6 C) and a high oxidation level of titanomagnetites (sample 179, Fig. 8). 2. Component B - steep positive vectors of the characteristic Inch (samples Igy224m2, Mrh142m2 and Mrh176t2, Fig. 10, Fig. 14 A, Table. 2). Found in outcrops 20/10 and 16÷18/14. Component B is typical of the outcrops with significant deviations of the axes of the AMS ellipse (Fig. 6 D, E), which suggests epigenetic changes in the basalts. New occurrences of titanomaghemites are observed in the studied outcrops (sample 228, Fig. 8), which leads to an almost complete destruction of vector In0 and formation of viscous NRM - Inv, which are oriented in the direction similar to the geomagnetic field. This conclusion is supported by the 'artificial magnetization reversal' tests (Fig. 11 A). 3. Component C - negative vectors of the characteristic NRM are clustered in the first sector of the stereogram at angles varying from -50 to -40° (Fig. 12, Fig. 14, Table 2). Found in four outcrops at the Ygyatta river (outcrops 17/10, and 21÷23/10). 4. Component D - positive vectors of the characteristic NRM are clustered in the third sector of the stereogram at angles varying from 40 to 50° (Fig. 13, Fig. 14, Table 2). Found in four outcrops at the Markha river (outcrops 20A, 20B, and 20C/14). The primary origin of characteristic components C and D of the basalts is determined as follows: - The 'sedimentary' type of AMS (Fig. 6 E, and Fig. 6 F); - According to the differential thermomagnetic analysis (DTMA), the mineral carrier of magnetization is virtually unaltered titanomagnetite with the Curie point of ≈550°C (samples 254 and 204, Fig. 8); - The presence of samples with negative NRM vectors (Table 1); - The magnetically stable state of the components is confirmed by high values of hysteresis parameters (Fig. 7) and the 'artificial magnetization reversal' experiment (Fig. 11 B). - The positive inversion test (Table 3, Fig. 14 B, and Fig. 14 C): γ/γc=5.1/6.2 at the sample level, and γ/γc=8.7/16.2 at the site level. Discussion. Data on 12 sites and previously published values were used to calculate the reference paleomagnetic pole (PMP) (Fran) (Table 5, Fig. 15, A). The PMP coordinates are as follows: latitude φ=1.7°, longitude λ=92.8°, and confidence intervals dp/dm=3.7/5.9°. The PMP's paleomagnetic reliability index is high enough, and the PMP can be thus considered as a reference for the Frasnian period (370±5 Ma). On this basis, taking into account the previous paleomagnetic data, paleomagnetic reconstructions of the Siberian platform, ranging from 420 up to 325 Ma, are obtained in our study (Fig. 15, B). In the above-mentioned period of time, the Siberian platform gradually moved in one direction, mostly latitudinal, from 11° to 25° N. After the Appainskaya time, the latitudinal movement was replaced by motions in the predominantly meridional eastward direction, and the average displacement velocity in these segments increased from 4.4 to 6.7 cm/year. It is possible that after the formation of the Appainskaya suite (Fran), the Siberian platform could pass the three hot spots representing the modern Atlantic islands near the northwestern coast of Africa (Canary, Madeira and Azores, i.e. The northern flank of the African superplume). These hotspots might have formed the tracks (Fig. 15) that controlled the intrusion of alkaline ultrabasic melts and formation of kimberlites in the Late Devon - Early Carbon. Conclusion. In the lower stream composed of the palagonite plagiophyre basalts of the Appainskaya suite, the paleomagnetic studies reveal two primary components of the NRM vectors, from bottom to top, D and C, respectively, with the direct and reverse polarity. Their presence in the basalts is marked by the 'sedimentary' type of AMS, practically un-oxidized titanomagnetites, and the positive inversion test. The reference PMP for the basalts of the Appainskaya suite, which is determined in our studies, provides for a more precise definition of the paleogeographic position and reconstruction of the drift of the Siberian platform in the Middle Paleozoic (from 420 to 325 Ma) and makes it possible to associate this drift with probable energy sources (i.e. hot spots), which might have been related to the intrusion of kimberlites
Accretion disks around Black Holes with Advection and Optical Depth Transition
We consider the effects of advection and radial gradients of pressure and
radial drift velocity on the structure of accretion disks around black holes
with proper description of optically thick/thin transitions. We concentrated
our efforts on the models with large accretion rate. Contrary to disk models
neglecting advection, we find that continuous solutions extending from the
outer disk regions to the inner edge exist for all accretion rates we have
considered. We show that the sonic point moves outward with increasing
accretion rate, and that in the innermost disk region advection acts as a
heating process that may even dominate over dissipative heating. Despite the
importance of advection on it's structure, the disk remains geometrically thin.
Global solutions of advective accretion disks, which describe continuously the
transition between optically thick outer region and optically thin inner region
are constructed and analyzed.Comment: 13 pages, 8 figures, to be published in Proceedings of the Gamov
Memorial International Conference, Odessa, Ukraine, August 8-14, 2004,
Cambridge Scientific Publication
Pseudo-Newtonian Potential for Charged Particle in Kerr-Newman Geometry
We consider the equatorial circular motion of a test particle of specific
charge q/m << 1 in the Kerr-Newman geometry of a rotating charged black hole.
We find the particle's conserved energy and conserved projection of the angular
momentum on the black hole's axis of rotation as corrections, in leading order
of q/m, to the corresponding energy and angular momentum of a neutral particle.
We determine the centripetal force acting on the test particle and,
consequently, we find a classical pseudo-Newtonian potential with which one can
mimic this general relativistic problem.Comment: 8 page
Vortex studies in superconducting Ba(Fe0.93Co0.07)2As2
We present small-angle neutron scattering (SANS) and Bitter decoration
studies of the superconducting vortices in
Ba(FeCo)As}. A highly disordered vortex configuration
is observed at all measured fields, and is attributed to strong pinning. This
conclusion is supported by the absence of a Meissner rim in decoration images
obtained close to the sample edge. The field dependence of the magnitude of the
SANS scattering vector indicates vortex lattice domains of (distorted)
hexagonal symmetry, consistent with the decoration images which show primarily
6-fold coordinated vortex domains. An analysis of the scattered intensity shows
that this decreases much more rapidly than expected from estimates of the upper
critical field, consistent with the large degree of disorder.Comment: 5 pages, 4 figure
Synthesis and antifungal activity of monoterpenoids of the carane series
The antifUngal activity of terpenoids of the carane series was studied; an interaction was found between the structures of these compounds and their antifungal properties. The actions of several terpenoids on the adhesive activity and enzyme systems of the fungus Candida albicans were studied. © 2012 Springer Science+Business Media, Inc
Structural and functional effects of two stabilizing substitutions, D137L and G126R, in the middle part of a-tropomyosin molecule
Protecting Mice from H7 Avian Influenza Virus by Immunisation with a Recombinant Adenovirus Encoding Influenza A Virus Conserved Antigens
Influenza is a highly contagious disease that causes annual epidemics and occasional pandemics. Birds are believed to be the source of newly emerging pandemic strains, including highly pathogenic avian influenza viruses of the subtype H7. The aim of the study: to evaluate the ability of the recombinant human adenovirus, serotype 5, which expresses genes of influenza A highly conserved antigens (ion channel M2 and nucleoprotein NP), to provide protection to laboratory mice against infection with a lethal dose of avian influenza virus, subtype H7. To achieve this goal, it was necessary to adapt influenza A virus, subtype H7 for reproduction in the lungs of mice, to characterise it, and to use it for evaluation of the protective properties of the recombinant adenovirus. Materials and methods: avian influenza virus A/Chicken/NJ/294508-12/2004 (H7N2) was adapted for reproduction in the lungs of mice by repeated passages. The adapted strain was sequenced and assessed using hemagglutination test, EID50 and LD50 for laboratory mice. BALB/c mice were immunised once with Ad5-tet-M2NP adenovirus intranasally, and 21 days after the immunisation they were infected with a lethal dose (5 LD50) of influenza virus A/Chicken/NJ/294508-12/2004 (H7N2) in order to assess the protective properties of the recombinant adenovirus. The level of viral shedding from the lungs of the infected mice was evaluated by titration of the lung homogenates in MDCK cell culture on days 3 and 6 after infection. The level of specific antibodies to H7 avian influenza virus was determined by indirect enzyme immunoassay. Results: the use of Ad5-tet-M2NP adenovirus for immunisation of the mice ensured 100% survival of the animals that had disease symptoms (weight loss) after their infection with the lethal dose (5 LD50) of H7 avian influenza virus. The study demonstrated a high post-vaccination level of humoral immune response to H7 avian influenza virus. The virus titer decreased significantly by day 6 in the lungs of mice that had been immunised with Ad5-tet-M2NP compared to the control group. Conclusion: the Ad5-tetM2NP recombinant adenovirus can be used to create a candidate pandemic influenza vaccine that would protect against avian influenza viruses, subtype H7, in particular
Combination of Endobronchial Ultrasound and Modern Cytological Diagnosis in Patients With Intrathoracic Lesions
Objective: To evaluate the effectiveness of endobronchial (EBUS) and endoscopic ultrasound (EUS) in cytomorphological verification of a malignant process using the transbronchial needle aspiration (TBNA) of the lymph nodes and mediastinal organs.Materials and methods: In 2017–2019 we analyzed the cytological samples (standard and cell block) of 172 patients (115 males and 57 females) with an average age of 61 years (25–82 years) in the clinical diagnostic laboratory of Scientific Research Institute – Ochapovsky Regional Clinical Hospital No. 1 (Krasnodar, Russian Federation). Of them 111 were used for immunocytochemical analysis. The majority of the studies (77) were performed in patients with lung cancer in order to identify the stage of the disease. We used combined bronchoscopy under general anesthesia in the operating room with high-frequency ventilation and a rapid on-site evaluation (ROSE).Results: We found the lymph node and mediastinal invasion in 140 (81%) patients who underwent EBUS-EUS TBNA. The non-diagnostic results were obtained in 32 (19%) patients. The combination of EUS and EBUS with TBNA showed the highest effectiveness in the mentioned clinical cases. The sensitivity, specificity, and accuracy of the cytologic analysis during EBUS and EUS with TBNA and no ROSE were 89%, 100%, and 90%, respectively. ROSE reduced the rate of non-diagnostic results and increased the sensitivity (96%), specificity (100%), and accuracy (97%) of the cytologic evaluation.Conclusions: According to the obtained results, we recommend using EBUS-EUS TBNA modalities for morphological verification of the mediastinal lymph nodes as a routine invasive diagnosis component of the preoperative evaluation in patients with lung cancer
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