Multifrequency Study of Giant Radio Pulses from the Crab Pulsar with the K5 VLBI Recording Terminal

Simultaneous multifrequency observations of the Crab pulsar giant pulses (GPs) were performed with the 64-m Kalyazin radio telescope at four frequencies 0.6, 1.4, 2.2 and 8.3 GHz using the K5 VLBI recording terminal. The K5 terminal provided continuous recording in 16 4-MHz wide frequency channels distributed over 4 frequency bands. Several thousands of GPs were detected during about 6 hours of observations in two successive days in July 2005. Radio spectra of single GPs were analysed at separate frequencies and over whole frequency range. These spectra manifest notable modulation over frequency ranges, $\Delta\nu$, both on large ($\Delta\nu/\nu\approx 0.5$) and small ($\Delta\nu/\nu\approx 0.01$) frequency scales. Cross-correlation analysis of GPs at 2.2 GHz showed that their pulse shapes can be interpreted as an ensemble of unresolved bursts grouped together at time scales of $\approx 1$ mcs being well-correlated over a 60-MHz band. The corresponding GP cross-correlation functions do not obey the predictions of the amplitude-modulated noise model of Rickett (1975), thus indicating that unresolved components represent a small number of elementary emitters.Comment: 22 pages, 11 figures, 3 tables, submitted to PAS

Giant Pulses -- the Main Component of the Radio Emission of the Crab Pulsar

The paper presents an analysis of dual-polarization observations of the Crab pulsar obtained on the 64-m Kalyazin radio telescope at 600 MHz with a time resolution of 250 ns. A lower limit for the intensities of giant pulses is estimated by assuming that the pulsar radio emission in the main pulse and interpulse consists entirely of giant radio pulses; this yields estimates of 100 Jy and 35 Jy for the peak flux densities of giant pulses arising in the main pulse and interpulse, respectively. This assumes that the normal radio emission of the pulse occurs in the precursor pulse. In this case, the longitudes of the giant radio pulses relative to the profile of the normal radio emission turn out to be the same for the Crab pulsar and the millisecond pulsar B1937+21, namely, the giant pulses arise at the trailing edge of the profile of the normal radio emission. Analysis of the distribution of the degree of circular polarization for the giant pulses suggests that they can consist of a random mixture of nanopulses with 100% circular polarization of either sign, with, on average, hundreds of such nanopulses within a single giant pulse.Comment: 13 pages, 6 figures (originally published in Russian in Astronomicheskii Zhurnal, 2006, vol. 83, No. 1, pp. 62-69) translated by Denise Gabuzd

Мониторинг паразитарных болезней продуктивных животных на территории Самарской области

The purpose of the research: to monitor the epizootic situation on parasitic diseases in productive animals in the Samara region using a database. materials and methods. Research was performed at the Department of invasive diseases of Samara Research Veterinary Station Samara RVS FSBSI. Fecal samples from productive animals were examined by Fuelleborn’s method using polymerase chain reaction to visualize species-specific DNA sequences, and an immune chromatographic method in detecting of antigens Dirofilaria immitis in serum, plasma and whole blood of dogs and oocysts Giardia duodenalis in dogs’ feces. The extensity of invasion was estimated with regard to the number of analyses of biomaterial from animals whose owners consulted veterinary physicians. For the monitoring, we used the database “Parasitic diseases in productive animals and small domestic animals in the Samara region” developed in Samara RVS in 2013 which enables to monitor the health status of the animal during its lifetime as well as epizootic situation on parasitic diseases in single localities, economies, districts and in Samara region in general. Results and discussion. Research results revealed that Strongylata had been registered in 17 districts at extensity of invasion from 5 to 70%, Strongyloides, Moniezia, Trichocephala - in 10 districts (EI 10-80%), Skrjabinema - in 7 districts ( EI 5-10%), Nematodirus - in 5 districts (EI 20-80%), Parascaris, Ascaris, Paramphistomum - in 3 districts (EI 5-40%), Fasciola, Coccidia, Dictyocaulus - in 2 districts (EI 5-15%). The biggest species diversity of helminths (7 species) were found in Bolsheglushitsky, Kinelsky and Borsky districts of the Samara region. The monitoring showed the decrease in worm species diversity in 2016 in all districts of Samara region compared to 2015. Parasitic protozoans, Eimeria, were found in all districts of the Samara region. A significant reduction of worm species diversity was associated with permanent planned treatment of productive animals with anthelmintics. The results obtained were used in a number of livestock farms of the Samara region to control the epizootic situation as well as for treatment and prevention of diseases in productive animals.Цель исследований: провести мониторинг эпизоотической ситуации паразитарных болезней продуктивных животных в районах Самарской области с использованием базы данных. Материалы и методы. Научные исследования проводили на базе отдела инвазионных болезней Самарской научно-исследовательской ветеринарной станции. Пробы фекалий от продуктивных животных исследовали по методу Фюллеборна, полимеразной цепной реакцией для выделения видоспецифических последовательностей ДНК и иммунохроматографического метода путем выявления антигенов Dirofilaria immitis в сыворотке, плазме и цельной крови собак и ооцист Giardia duodenalis в фекалиях собак. Экстенсивность инвазии рассчитывали по отношению к числу проведенных анализов биоматериала от животных, владельцы которых обращались за ветеринарной помощью. Для мониторинга использовали разработанную в Самарской НИВС базу данных «Паразитарные заболевания продуктивных и мелких домашних животных в Самарской области», которая позволяет отслеживать состояние здоровья животного в течение его жизни, а также эпизоотическую ситуацию по паразитозам в отдельных населенных пунктах, хозяйствах, районах и по Самарской области в целом. Результаты и обсуждение. В результате проведенных исследований было установлено, что стронгилята были зарегистрированы в 17 районах при экстенсивности инвазии от 5 до 70%, стронгилоиды, мониезии, трихоцефалы - в 10 районах (10-80%), скрябинема - в 7 районах (5-10%), нематодиры - в 5 районах (20-80%), параскариды, аскариды, парамфистомы - в 3 районах (5-40%), фасциолы, кокцидии, диктиокаулы - в 2 районах (5-15%). Наибольшее видовое разнообразие гельминтов (7 видов) отмечено в Большеглушицком, Кинельском, Борском районах области. Мониторинг показал, что число видов гельминтов в 2016 г. по сравнению с 2015 г. снизилось во всех районах области. Простейших рода Eimeria выявляли во всех районах области. Значительное снижение видового состава гельминтов связано с планомерным проведением плановых обработок продуктивных животных антигельминтными препаратами. Полученные результаты были использованы в ряде животноводческих хозяйств Самарской области для контроля эпизоотологической ситуации, а также лечения и профилактики болезней продуктивных животных

Shapiro Effect as a Possible Cause of the Low-Frequency Pulsar Timing Noise in Globular Clusters

A prolonged timing of millisecond pulsars has revealed low-frequency uncorrelated noise, presumably of astrophysical origin, in the pulse arrival time (PAT) residuals for some of them. In most cases, pulsars in globular clusters show a low-frequency modulation of their rotational phase and spin rate. The relativistic time delay of the pulsar signal in the curved space time of randomly distributed and moving globular cluster stars (the Shapiro effect) is suggested as a possible cause of this modulation. Given the smallness of the aberration corrections that arise from the nonstationarity of the gravitational field of the randomly distributed ensemble of stars under consideration, a formula is derived for the Shapiro effect for a pulsar in a globular cluster. The derived formula is used to calculate the autocorrelation function of the low-frequency pulsar noise, the slope of its power spectrum, and the behavior of the $\sigma_z$ statistic that characterizes the spectral properties of this noise in the form of a time function. The Shapiro effect under discussion is shown to manifest itself for large impact parameters as a low-frequency noise of the pulsar spin rate with a spectral index of n=-1.8 that depends weakly on the specific model distribution of stars in the globular cluster. For small impact parameters, the spectral index of the noise is n=-1.5.Comment: 23 pages, 6 figure

Test Items Validation in the Context of Education Export

It is necessary to develop special assessment tools for international students, which will comply with the principles of evidence-based education. This is especially important in the context of Russian higher education export. Multiple choice questions (MCQs) are an essential part of the assessment and are suited for assessing the knowledge level of international students. The “Organic chemistry” is a basic course for pharmaceutical students, which is necessary for the understanding of principal subjects. The study objective was to develop a normative-oriented model of the “Organic chemistry” MCQs based examination for international students (the specialty 33.05.01 “Pharmacy”) in accordance with the recommendations of the Association for Medical Education in Europe (AMEE). The previously developed interactive “Organic Chemistry Test Simulator”, created at the Sechenov University, was used as the basis for the examination MSQs bank. It was analyzed by five independent experts, who work as teachers of organic chemistry. The average timing and the cut score were determined by the Angoff method, 90 sec and 64%, respectively. Among analyzed MCQs the 3% were found irrelevant, 22% were recommended for revision and modernization. Valid MSCs (600 items) served as the basis for the creation of extended examination MSQs bank. An algorithm for modeling the “Organic chemistry” MCQs based examination was proposed. The standardized examination test has 30 MSQs of different types. The standardized normative-oriented model of the “Organic chemistry” MCQs based examination for international students (the specialty 33.05.01 “Pharmacy”) was validated in terms of relevance and representativeness, optimized in time and cut score