55 research outputs found

    Management of multi- and extensively drug-resistant tuberculosis in Ukraine: how well are we doing?

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    Setting: A tertiary care facility in Ukraine, a high multi- and extensively drug-resistant tuberculosis (MDR/XDR-TB) burden country. Objectives: To assess the management and treatment outcomes of MDR, pre-XDR-TB and XDR-TB. Design: Cohort study using programme data, 2006–2011. Results: Of 484 individuals with drug-resistant TB, 217 (45%) had MDR-, 153 (32%) pre-XDR- and 114 (24%) XDR-TB. Of all resistant types completing the intensive phase of treatment, 322 (67%) were alive and had culture converted. This included 157 (72%) with MDR- and 61 (54%) with XDR-TB. At the end of the continuation phase of treatment, 106 (22%) had treatment success and 378 (78%) had unfavourable outcomes, including 110 (23%) failures, 21 (4%) deaths, 71 (15%) losses to follow-up and 176 (36%) with an unknown outcome. This was associated with more than one lung cavity being affected, a history of treatment with second-line anti-tuberculosis drugs, poor adherence and XDR-TB. A total of 226 (47%) patients reported at least one adverse drug reaction, the most common being gastrointestinal and vestibular toxicity. Conclusion: Outcomes of MDR- and XDR-TB were satisfactory in the intensive phase; however, this was not sustained during the ambulatory period. If we are to do better, urgent measures are needed to improve ambulatory management, including making safer, shorter and more effective drug regimens available

    Asymmetric Electrostatic Dodecapole: Compact Bandpass Filter with Low Aberrations for Momentum Microscopy

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    Imaging energy filters in photoelectron microscopes and momentum microscopes employ spherical fields with deflection angles of 90{\deg}, 180{\deg} and even 2 x 180{\deg}. These instruments are optimized for high energy resolution, yet they come along with image aberrations when they are operated in high transmission mode with medium energy resolution. Here we present a new approach for bandpass-filtered imaging in real or reciprocal space, using an asymmetric electrostatic dodecapole. This multipole enables energy-dispersive beam deflection and correction of image aberrations up to the 3rd order. Owing to a deflection angle of only 4{\deg}, the total beam displacement in the filter is just ~10 mm. Hence, the entire instrument is compact and just requires a straight vacuum tube. The multipole is framed by transfer lenses in the entrance and exit branch. Two sets of 16 entrance and exit apertures with different sizes on piezomotor-driven holders allow selecting the desired resolution. The combination of apertures and dodecapole acts as a bandpass pre-selector in a high-energy time-of-flight momentum microscope at the hard X-ray beamline P22 at PETRA-III (DESY, Hamburg). At pass energies between 400 and 600 eV it transmits electrons with kinetic energies in the range of 20-40 eV and thus effectively eliminates unwanted intensity from higher-energy electrons in the ToF analyzer. At low pass energies, the instrument allows energy-filtered imaging without subsequent ToF analysis. In a laboratory experiment the 4{\deg} prototype reached < 500 meV resolution, which is sufficient for fast survey studies in the X-ray range.Comment: 16 pages, 6 figures, 26 reference

    Terahertz Néel spin-orbit torques drive nonlinear magnon dynamics in antiferromagnetic Mn2Au

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    Antiferromagnets have large potential for ultrafast coherent switching of magnetic order with minimum heat dissipation. In materials such as Mn2Au and CuMnAs, electric rather than magnetic fields may control antiferromagnetic order by Néel spin-orbit torques (NSOTs). However, these torques have not yet been observed on ultrafast time scales. Here, we excite Mn2Au thin films with phase-locked single-cycle terahertz electromagnetic pulses and monitor the spin response with femtosecond magneto-optic probes. We observe signals whose symmetry, dynamics, terahertz-field scaling and dependence on sample structure are fully consistent with a uniform in-plane antiferromagnetic magnon driven by field-like terahertz NSOTs with a torkance of (150 ± 50) cm2 A−1 s−1. At incident terahertz electric fields above 500 kV cm−1, we find pronounced nonlinear dynamics with massive Néel-vector deflections by as much as 30°. Our data are in excellent agreement with a micromagnetic model. It indicates that fully coherent Néel-vector switching by 90° within 1 ps is within close reach

    Information technology forecasting cyclical economic processes

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    Розроблено інформаційну технологію прогнозування циклічних економічних процесів, яка характеризується більшою точністю у порівнянні із відомими методами прогнозування на базі теорії періодичних випадкових процесів. Представлено результати прогнозу індексу маркетингу та реклами США на 2011р. і його циклічної компоненти на основі моделі у вигляді циклічного випадкового процесу та періодичного випадкового процесу.The information technology of cyclical economic forecasting processes was designed and characterized with greater accuracy in comparison with the known methods of forecasting based on the theory of periodic random processes. The forecast results of the USA marketing and advertising indexes were presented in 2011 and its cyclical component based on the model in cyclic and periodic form of random process

    Valence-transition-induced changes of the electronic structure in EuPd2_2Si2_2

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    We present results of hard X-ray angle-resolved photoemission spectroscopy and photoemission diffraction measurements performed on high-quality single crystals of the valence transition compound EuPd2_2Si2_2 for temperatures 25~K \leq T \leq 300~K. At low temperatures we observe a Eu 4f4f valence v=2.5v=2.5, % occupation number n=6.5n=6.5, which decreases to v=2.1v=2.1 for temperatures above the valence transition around TV160T_V \approx 160~K. The experimental valence numbers resulting from an evaluation of the Eu(III)/Eu(II) 3d3d core levels, are used for calculating band structures using density functional theory. The valence transition significantly changes the band structure as determined by angle-resolved photoemission spectroscopy. In particular, the Eu 5d5d valence bands are shifted to lower binding energies with increasing Eu 4f4f occupancy. To a lesser extent, bands derived from the Si 3p3p and Pd 4d4d orbitals are also affected. This observation suggests a partial charge transfer between Eu and Pd/Si sites. Comparison with {\it ab-initio} theory shows a good agreement with experiment, in particular concerning the unequal band shift with increasing Eu 4f4f occupancy

    Diagnostic errors during intramedullar processes

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    Introduction: The article describes a clinical case of a malignant tumor of the brain and spinal cord with metastasis, which remained undetected for many years and was treated as syringomyelia. Long-term exhausting examinations of the brain and spinal cord, dynamic follow-up of medical specialists, and repeated surgical interventions on the spine helped to differentiate this process and make the correct diagnosis. The aim: The objectives of the present paper are to analyze the existing classifications of syringomyelia; to examine its etiology, pathogenesis, diagnostic approaches and treatment tactics; to present a clinical case of a malignant tumor of the brain and spinal cord with metastasis, which was misdiagnosed as syringomyelia. Materials and methods: The authors analyzed the existing classifications of syringomyelia and studied its etiology, pathogenesis, diagnostic approaches and treatment tactics using the method of content analysis, analyticalб comparative and contrastive methods. Clinical case: The described clinical case is a variant of the course of syringomyelia, associated with the spinal cord tumor, namely, in particular, anaplastic ependymoma. For a long time, the process remained undetected, despite the long-term examination and drainage of the syringomyelic cavity. Analyzing this case, it is highly important to pay attention to careful history collection, examination of the patient, analysis of the occurrence of certain disorders in order to conduct the neuroimaging examinations in time. Conclusions: Favorable outcome of the disease is directly related to the diagnosis at early stages, especially in young people, the clinical variant of the process, progression of the course, the degree of involvement of various parts of the nervous system and extraneural formations, the severity of the lesion. The treatment tactics and the ability to restore the functions will depend on all these factors
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