Mach-Zehnder FOPA for Dual Polarization Wavelength-Division-Multiplexed 100G Signal Amplification

We demonstrate amplification of 17x100 GHz-spaced channel in C-band by a PI-FOPA based on Mach-Zehnder architecture with net gain >10 dB and confirmed its robustness over time. A commercial 100G-PDM-QPSK transponder was used to measure/compare the bit-error-rate versus received power with a commercial EDFA

Phase-sensitive amplification of 11 WDM channels across bandwidth of 8 nm in a fibre optic parametric amplifier

We experimentally demonstrate phase-sensitive fibre optic parametric amplification with gain >10dB and optical noise figure below 3dB for 11 channels spaced of 100 GHz. We employ all-fibre dispersion management to achieve a wideband phase-matching between signals and their copies

Raman-amplified pump and its use for parametric amplification and phase conjugation

We experimentally demonstrate the use of a discrete Raman amplifier for generating a high power, narrow linewidth pump for use within a fiber optical parametric amplifier (FOPA). We demonstrate the suitability of the Raman-amplified pump for parametric amplification by characterizing its optical signal to noise ratio and relative intensity noise (RIN). The amplified pump is subsequently employed within a FOPA obtaining net gain of up to 24.9 dB and a gain of >11 dB over 35 nm. The approach described here offers the key advantage over traditional EDFA-based pump generation of wavelength tuneability outside the EDFA bands. In principle this allows to place the parametric pump at any wavelength within the low fiber attenuation window. Here we additionally demonstrate Raman-assisted optical phase conjugation to provide positive conversion efficiency over 60 nm whilst employing the phase-conjugating pump power of <10 mW not requiring an amplification by EDFA. We consider this technique to show a significant promise for broadband optical phase conjugation and wavelength conversion as well as the prospect for implementation of these important phenomena outside of the EDFA bands

Biomedical sports and recreational activities

In modern Russia today mainly drawn the attention to the study of the issues of further development of physical culture and sports. Very important for its further development and functioning are medical and biological aspects. As knowledge about a person are the foundation of athletic training content frame underlie the science of physical culture, one only needs to reflect society in purposeful motor activity. Despite the considerable efforts of health, unfortunately, is still the same problem: the health status of physical fitness and physical development of the wider population. At this time, do not create a strong system, there is a shortage of personnel, who could teach "HLS ". In the youth from low employment prevalent bad habits to drug use, drinking alcohol and smoking. This contributes to a violation of the organs and diviantnomu behavior. Little attention is paid to the disabledВ современной России на сегодняшний день главным образом обращается внимание специалистов на изучение вопросов дальнейшего развития физической культуры и спорта. Очень большое значение для её дальнейшего развития и функционирования имеют медико-биологические аспекты. Поскольку знания о человеке составляют фундамент содержания профессиональной подготовки физкультурных кадров, лежат в основе науки о физической культуре, отражают единственные потребности социума в целенаправленной двигательной деятельности. Несмотря на значительные усилия здравоохранения, к огромному сожалению, остаётся всё та же проблема состояния здоровья физической подготовленности и физического развития широких слоёв населения. В данное время не создано крепкой системы, наблюдается дефицит кадров, которые могли бы преподавать «ЗОЖ». В среде молодёжи от малой занятости распространены вредные привычки к употреблению наркотиков, распитию спиртных напитков, курению. Это способствует нарушению работы органов и девиантному поведению. Мало внимания уделяется инвалидам

ПРОФЕССИОНАЛЬНОЕ САМООПРЕДЕЛЕНИЕ КАК ПСИХОГЕНЕТИЧЕСКИЙ ВЫБОР ПРОФЕССИИ НА ОСНОВАНИИ АНАЛИЗА ГЕНЕТИЧЕСКОГО ДРЕВА И ОЦЕНКИ ВНУТРЕННИХ РЕСУРСОВ СУБЪЕКТА

The article considers the phenomenon of psychogenetic career choice based on the analysis of the genetic tree and the assessment of the internal resources of the subject, the issues of interrelation between the predetermination of professional choice on the basis of the genetic factor and the formation of personality in development, taking into account the influence of environmental conditions on this process, other persons (parents, teachers, peers) are considered in detail.The article contains articles by well-known Russian and foreign scientists who have the results of many years of research and observations on this topic.В статье рассмотрен феномен психогенетического выбора профессии на основании анализа генетического древа и оценки внутренних ресурсов субъекта, подробно рассмотрены вопросы взаимосвязи между предопреде-ленностью профессионального выбора на основании генетического фактора и формированием личности в развитии, с учетом влияния на данный процесс условий среды, других лиц (родителей, преподавателей, сверстников).В работе использованы статьи известных российских и зарубежных ученых, имеющих по данной теме результаты многолетних исследований и наблюдений

In-line and cascaded DWDM transmission using a 15dB net-gain polarization-insensitive fiber optical parametric amplifier

We demonstrate and characterize polarization-division multiplexed (PDM) DWDM data transmission for the first time in a range of systems incorporating a net-gain polarization-insensitive fiber optical parametric amplifier (PI-FOPA) for loss compensation. The PI-FOPA comprises a modified diversity-loop architecture to achieve 15dB net-gain, and up to 2.3THz (~18nm) bandwidth. Three representative systems are characterized using a 100Gb/s PDM-QPSK signal in conjunction with emulated DWDM neighbouring channels: (a) a 4x75km in-line fiber transmission system incorporating multiple EDFAs and a single PI-FOPA (b) N cascaded PI-FOPA amplification stages in an unlevelled Nx25km recirculating loop arrangement, with no EDFAs used within the loop signal path, and (c) M cascaded PI-FOPA amplification stages as part of an Mx75.6km gain-flattened recirculating loop system with the FOPA compensating for the transmission fiber loss, and EDFA compensation for loop switching and levelling loss. For the 4x75km in-line system (a), we transmit 45x50GHz-spaced signals (‘equivalent’ data-rate of 4.5Tb/s) with average OSNR penalty of 1.3dB over the band at 10−3 BER. For the unlevelled ‘FOPA-only’ 25.2km cascaded system (b), we report a maximum of eight recirculations for all 10x100GHz-spaced signals, and five recirculations for 20x50GHz-spaced signals. For the 75.6km levelled system (c), we achieve eight recirculations for all 20x50GHz signals resulting in a total transmission distance of 604.8km

Theory of high harmonic generation in relativistic laser interaction with overdense plasma

High harmonic generation due to the interaction of a short ultra relativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultra relativistic similarity theory we show that the high harmonic spectrum is universal, i.e. it does not depend on the interaction details. The spectrum includes the power law part $I_n\propto n^{-8/3}$ for $n<\sqrt{8\alpha}\gamma_{\max}^3$, followed by exponential decay. Here $\gamma_{\max}$ is the largest relativistic $\gamma$-factor of the plasma surface and $\alpha$ is the second derivative of the surface velocity at this moment. The high harmonic cutoff at $\propto \gamma_{\max}^3$ is parametrically larger than the $4 \gamma_{\max}^2$ predicted by the ``oscillating mirror'' model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic $\gamma$-factor of the plasma surface. These spikes define the high harmonic spectrum and lead to attosecond pulses in the reflected radiation.Comment: 12 pages, 9 figure

Features of soils of the natural park “Scherbakovsky” Volgograd region

The paper presents the results of a study of the soil cover of the Shcherbakovsky Nature Park in the Kamyshinsky district of the Volgograd region. To achieve the results 12 soil sections were laid along the studied soil catena (1.5 km), so that morphological and chemical features of the soils of the study area were investigated. Variety and diversity are due to vertical zonality and geological and hydrological peculiarities. So, in the gullies and in massive forest plantations various dark humus and gley soils have become widespread. On steppe, slope and watershed areas lithosolic light humus luvisols and light humus lithozems were formed. On areas with open sand surface, humus psammozems with protohumus horizons W, as well as light humus (AJ-C) and humus soils (A-C), and a variety of soil-forming rocks of the natural park were found. In relief depressions they are represented mainly by gleyed sandy, as well as proluvial-deluvial deposits with inclusions of large fragments of opokas. On steppe and steep-slope areas, the soil-forming rocks are thick layers of opoka deposits. Their upper boundary varies from 20 to 60 cm depth depending on the meso- and microrelief. On the watersheds, the soilforming rocks are represented by sandy, ferruginous deposits with new formations of clay and pseudofibres. The parent rock is registered starting from 100 cm depth and consists of large blocks of hardened sandstone. The chemical properties of the studied soils are characterized by a neutral or slightly acidic pH. Easily soluble salts are leached from all soil horizons. The maximum values of Сorg are typical of humus and transitional horizons. The studies conducted in the Shcherbakovsky Nature Park are of greatest importance for monitoring the state of soils, and also allowed us to identify the features of the genesis of underdeveloped soils and luvisols of the dry-steppe natural zone

Some aspects of teaching medical informatics at medical universities

В статті розглядаються питання сучасного викладання медичної інформатики студентам медичних університетів. В роботі описано основну мету дисципліни, пропонуються шляхи вдосконалення її. Актуальність даної тематики підтверджує те, що наукові методи та інструментальні засоби все більш широко проникають в будь-які галузі життєдіяльності людини, і медицина не є виключенням, Саме це надає медичній інформатиці характер міждисциплінарної галузі, яка набуває все більш важливе загальнонаукове і загальноосвітнє значення. Розкрито важливе питання забезпечення формування у сучасного лікаря цілісного системного наукового світогляду на проблеми інформатизації охорони здоров'я. Дана стаття буде цікава викладачам закладів вищої медичної освіти.The article discusses the issues of up-to-date teaching medical informatics to students of medical universities. The paper describes the main goal of the discipline, suggests ways to improve it. The relevance of this topic lies in the fact that scientific methods and tools are increasingly penetrating into any branch of human life, and medicine is not an exception. That is why Medical Informatics belongs to interdisciplinary field, and acquires important scientific and educational value. Authors disclosed the important issue of the formation of a holistic and scientific worldview in modern doctors on the problems of health care informatization. This article would be interesting to teachers of higher educational institutions of a medical profile