Говоріння як пріоритетний аспект у викладанні англійської мови

Since language is a means of communication, teaching speaking is a prior task in any methodology. This article is devoted to the research of the main methods of teaching speaking. These methods are fully described and their importance and productivity are proved

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

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

Impact of pump phase modulation on QAM signals in polarization-insensitive fiber optical parametric amplifiers

We examine mitigation of stimulated Brillouin scattering (SBS) in fiber optical parametric amplifiers (FOPAs) by pump phase modulation in the context of QAM signals and the state-of-art polarization-insensitive FOPA architecture. We characterize the impact of the pump phase modulation on QAM signals in the cases of single-polarization FOPAs and polarization-insensitive FOPAs, and study pathways to minimization of this impact. We find that the impact of pump phase modulation on signals is more complicated in polarization-insensitive FOPAs than in single-polarization FOPAs, and it can be mitigated by using the features of the polarization-insensitive FOPA architecture. We use the required optical signal to noise ratio (rOSNR) to evaluate the impact of pump phase modulation on QAM signals and find that the induced signal phase modulation makes significantly more contribution than the induced signal amplitude modulation. Our numerical and experimental study has revealed a distribution of the rOSNR penalty across the FOPA gain spectrum which is distinct from previously reported for on/off signals. We explore and optimize the pump phase modulation schemes to reduce the signal rOSNR penalty whilst providing more SBS mitigation at the same time. We demonstrate that a receiver digital signal processing plays a significant role in contribution to rOSNR penalty

Multipurpose assessment of the financial competitiveness of a publishing company

The paper considers a set of theoretical, practical and methodological issues related to determining the level of competitiveness of publishing companies by forming an integral assessment. The methodology of the study is the application of the ranking system, the Fishburne method, the definition of the specific weights of indicators, allowing you to assess financial competitiveness of companies, the tools of graphic analysis to calculate the overall integrated indicators that characterize the level of competitiveness of the publishing company. The main findings of the study are to determine the level of competitive potential (LCP) of companies, through integral evaluation. The advantage of the assessment method used is the application of a system of financial, marketing and reputational indicators. This indicator system has made it possible to more accurately determine the level of financial competitiveness and improve the effectiveness of financial and investment decisions made in the publishing industry

Dynamics of soil freezing and thawing in the agroforestry landscape

The article presents the dynamics of soil freezing and thawing in the agroforestry landscape of the dry-steppe zone. These processes in winters with unstable snow cover have their own characteristics. The purpose of this study was to investigate the character of soil freezing and thawing in the agroforestry landscape under conditions of low snowfall winters. Observations were carried out in the winter period of 2020–2021 at the existing runoff-erosion research station in Volgograd. The dynamics of soil freezing and thawing was studied using Danilin freeze-thaw meters installed in the field and in the center of a four-row forest belt. Simultaneously, snow cover height was measured in triplicate with a snow measuring rod. The weather conditions were characterized by alternating thaws, which promoted snow cover melt, and frosts, which increased the depth of soil freezing. The formation of a 10-15 cm snow cover did not affect soil freezing. In the absence of snow on the background of a brief thaw, the lower boundary of the frozen layer in the field decreased by 11 cm compared to the forest belt, which even in the leafless state affected the inflow of solar thermal energy. Average freezing at the end of winter was 85 cm in the field and 67 cm in the forest belt. Thawing in the field was faster. During the first two weeks, the rate of soil thawing averaged 2.3 cm/day in the field and 1.3 cm/day in the forest belt. After that, the depth of freezing in the whole agroforestry landscape became equal. During the next two weeks, the thawing rate doubled. After complete soil thawing in the field in the forest belt, the thickness of the frozen layer averaged 32 cm

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

Complications of colorectal cancer in general surgical clinics

Facultatea de medicină, Universitatea din Transnistria, Tiraspol, Moldova, Catedra de Chirurgie generală, KhMAPO, Harkov, Ucraina, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Creşterea ratei de îmbolnăvire, rezultatele nesatisfăcătoare ale tratamentului şi multiplele probleme organizatorice nerezolvate în ajutorarea pacienţilor cu cancer de colon necesită măsuri de urgenţă. Scopul studiului: De a examina rezultatele directe ale tratamentului pacienţilor cu cancer complicat de colon şi rect, prin identificarea cauzelor de bază şi a celor indirecte care determină rezultatele nesatisfăcătoare. Material şi metode: Într-o regiune teritorială compactă cu o populaţie de circa 500.000 au fost analizate rezultatele tratamentului a 308 pacienţi cu cancer colo-rectal, supuşi intervenţiilor operatorii în Clinica de chirurgie generală. Pacienţii au fost repartizaţi în 2 grupuri: operaţi programat (157) şi operaţi de urgenţă (151). Rezultate: Între pacienţii incluşi în studiu au predominat cei operaţi planificat (52,3%). Vîrsta medie în grupuri a fost comparabilă, respectiv 58,7 şi 61,4 ani. După localizare, 40,8±3,9% pacienţi cu patologii urgente, au prezentat afecţiuni ale colonului descendent şi sigmoid. În ambele grupuri au fost prezenţi pacienţi în stadii tardive: la stadiile 3-4 – 90,4% (planificaţi) şi 100% (cu cancer colorectal complicat). Principalele complicaţii: obstrucţia intestinală 65,6% (99 pacienţi); la 48 pacienţi pe parcursul operaţiei a fost identificată peritonita din cauza rupturii intestinului sau microperforaţiilor tumorilor. Patru pacienţi au fost operaţi în legătură cu hemoragia tumorii decadente. La pacienţii planificaţi în 12,1% cazuri au fost identificate complicaţii similare. Operaţia radicală a fost posibilă în 70,4% cazuri în grupul 1 şi doar în 28,8% din grupul 2. În cazul operaţiilor planificate la 82,0% pacienţi a fost aplicată anastomoza primară, iar la pacienţii cu cancer colorectal complicat – doar la 50%; colostomia – în 25,2±3,6% cazuri (planificaţi) şi 54,4±4,1% (urgenţă). Mortalitatea – 14,9±2,0% cazuri. Concluzii: Rezultatele tratamentului pacienţilor cu cancer colorectal au fost agravate de frecvenţa înaltă a formelor complicate ale acestei patologii. Implementarea sistemelor de “screening” pentru detectarea precoce a cancerului colorectal, poate îmbunătăţi parametrii chirurgicali şi reduce frecvenţa formelor complicate de cancer colorectal.Introduction: The growth of the disease, consistently poor results and many unsettled organizational issues in patients with colon cancer call for urgent solving of the problem. The aim: To examine the results of treatment in patients with the complicated cancer of the colon and rectum. Material and methods: In the compact territorial area (population: 500.000) there were studied the outcomes of treating in 308 patients operated in general clinical hospital for colorectal cancer. The patients were distributed into 2 groups: elective (157) and urgent surgery (151). Results: The average age of the patients in the groups was identical, respectively – 58.7 and 61.4 years old. Taking into account the location, 40.8±3.9% of patients with urgent pathology had an affection of descending and sigmoid colon. In both groups of patients there were those with late stages: 3-4th stages – 90.4% (in group I), and 100% (in group II). The main complication was acute intestinal obstruction 65.6% (99 patients). In 48 patients there were general or local peritonitis. Four patients were operated in connection with the hemorrhage from tumor. In group I similar complications were only in 12.1% cases. Radical surgery: in group I – 70.4%, and only 28.8% – in group II. Primary anastomosis was possible in 82% cases in group I, and only in 50% cases from group II; colostomy – 25 versus 54 cases. Mortality rate – 14%. Conclusion: The treatment outcomes of patients with colorectal cancer were largely aggravated by the significant frequency of complicated forms of the disease. The implementation of the screening systems for early detection of cancer of the colon and rectum can improve the results of the surgical interventions and reduce the frequency of complicated forms of colorectal cancer

Strong laser fields as a probe for fundamental physics

Upcoming high-intensity laser systems will be able to probe the quantum-induced nonlinear regime of electrodynamics. So far unobserved QED phenomena such as the discovery of a nonlinear response of the quantum vacuum to macroscopic electromagnetic fields can become accessible. In addition, such laser systems provide for a flexible tool for investigating fundamental physics. Primary goals consist in verifying so far unobserved QED phenomena. Moreover, strong-field experiments can search for new light but weakly interacting degrees of freedom and are thus complementary to accelerator-driven experiments. I review recent developments in this field, focusing on photon experiments in strong electromagnetic fields. The interaction of particle-physics candidates with photons and external fields can be parameterized by low-energy effective actions and typically predict characteristic optical signatures. I perform first estimates of the accessible new-physics parameter space of high-intensity laser facilities such as POLARIS and ELI.Comment: 7 pages, Key Lecture at the ELI Workshop and School on "Fundamental Physics with Ultra-High Fields", 9 September - 2 October 2008 at Frauenworth Monastery, German