48 research outputs found
Bovine leukemia virus occurrence in Dagestan
Results of diagnostic tests for bovine leukosis carried out in the Dagestan Republic in 2022 (as of October 1, 2022) showing bovine leukemia virus (BLV) occurrence are presented in the paper for the whole Republic and for each municipality separately. In total, 632,454 susceptible animals were serologically tested with immunodiffusion assay; 3,573 reactor animals (0.6% of tested animals) were detected. Proportion of infected animals was as follows: 0.5% – in administrative raions, 1.6% – in urban districts and 1.1% – in distant pasture zones. Percentage of infected cattle varied from 0.01 to 4.9%. No hematological examinations for bovine leukosis were carried out because seropositive animals were timely culled. In the breeding sector, the proportion of bovine leukemia virus carriers was averagely 2.8%. Ninety-five bovine leukosis-affected localities were reported in the region as of 1 January 2022. Eighty-one new BLV-infected localities had been identified and bovine leukosis had been eliminated in 18 localities for 9 months of 2022. Totally, 158 localities were officially declared affected in 2022 (as of October 1, 2022): 36 agricultural holdings (including 5 breeding holdings), 18 small-scale farms and 104 backyard farms. The largest number of bovine leukosis-affected localities was registered in the Kizlyarsky (18), Tarumovsky (17), Babayurtovsky (16), Gunibsky (15), Tlyaratinsky (10) Raions and in the city of Makhachkala (9). One disease-affected locality was reported in each of the Bezhtinsky, Buynaksky, Derbentsky, Kazbekovsky, Kayakentsky, Kizilyurtovsky, Khasavyurtovsky Raions and towns of Khasavyurt and Yuzhno-Sukhokumsk. Two disease-affected localities were reported in each of the Rutulsky, Untsukulsky Raions, three disease-affected localities were reported in each of the Gergebilsky, Laksky, Novolaksky, Tsumadinsky Raions. Four disease-affected localities were reported in the Sergokalinsky Raion, five disease-affected localities were reported in the Charodinsky Raion, six disease-affected localities were reported in each of the Akhvakhsky, Dakhadaevsky, Karabudakhkentsky Raions, seven disease-affected localities were reported in each of the Botlikhsky, Kumtorkalinsky and Shamilsky Raions. Comparative analysis of serological and molecular genetic methods used for bovine leukosis diagnosis demonstrated the advantage of enzyme-linked immunosorbent assay and polymerase chain reaction as compared to immunodiffusion assay used in veterinary practice
Multi-Wavelength Monitoring of the Changing-Look AGN NGC 2617 during State Changes
Optical and near-infrared photometry, optical spectroscopy, and soft X-ray and UV monitoring of the changing-look active galactic nucleus NGC 2617 show that it continues to have the appearance of a type-1 Seyfert galaxy. An optical light curve for 2010-2017 indicates that the change of type probably occurred between 2010 October and 2012 February and was not related to the brightening in 2013. In 2016 and 2017 NGC 2617 brightened again to a level of activity close to that in 2013 April. However, in 2017 from the end of the March to end of July 2017 it was in very low level and starting to change back to a Seyfert 1.8. We find variations in all passbands and in both the intensities and profiles of the broad Balmer lines. A new displaced emission peak has appeared in Hβ. X-ray variations are well correlated with UV-optical variability and possibly lead by ̃2-3 d. The K band lags the J band by about 21.5 ± 2.5 d and lags the combined B + J bands by ̃25 d. J lags B by about 3 d. This could be because J-band variability arises predominantly from the outer part of the accretion disc, while K-band variability is dominated by thermal re-emission by dust. We propose that spectral-type changes are a result of increasing central luminosity causing sublimation of the innermost dust in the hollow bi-conical outflow. We briefly discuss various other possible reasons that might explain the dramatic changes in NGC 2617.Fil: Oknyansky, V. L.. Sternberg Astronomical Institute; RusiaFil: Gaskell, C. M.. Department of Astronomy and Astrophysics. University of California. Santa Cruz; Estados UnidosFil: Mikailov, K. M.. Shamakhy Astrophysical Observatory, National Academy of Sciences.
Pirkuli; AzerbaiyánFil: Lipunov, V. M.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University ; RusiaFil: Shatsky, N. I.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Tsygankov, S. S.. Tuorla Observatory, Department of Physics and Astronomy. University of Turku.; FinlandiaFil: Gorbovskoy, E. S.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Tatarnikov, A. M.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Metlov, V. G.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Malanchev, K. L.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Brotherton, M.B.. University of Wyoming; Estados UnidosFil: Kasper, D.. University of Wyoming; Estados UnidosFil: Du, P.. Institute of High Energy Physics. Chinese Academy of Sciences; ChinaFil: Chen, X.. School of Space Science and Physics. Shandong University; ChinaFil: Burlak, M. A.. Sternberg Astronomical Institute. M.V.Lomonosov Moscow State University; RusiaFil: Buckley, D. A. H.. The South African Astronomical Observatory; SudáfricaFil: Rebolo, R.. Instituto de Astrofisica de Canarias; EspañaFil: Serra-Ricart, M.. Instituto de Astrofisica de Canarias; EspañaFil: Podestá, R.. Universidad Nacional de San Juan; ArgentinaFil: Levato, O. H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentin
Analysis of complications after knee replacement in tumor lesions (20-year experience)
Purpose - retrospective analysis of the causes of complications after knee replacement in tumor lesions depending on the type of implants and classification of complications by severity. Material and methods. The outcomes of operations of knee replacementin tumor lesions performed in 161 patients in the period between 1993 and 2012 were studied. All patients were divided into two groups. The first group included 68 (42.2%) patients, whom the Russian endoprostheses were implanted. The second group included 93 (57.8%) patients, who were operated using modern foreign endoprostheses. Results. 74 (45.9%) patients underwent revision surgery due to the complications in different terms after primary oncologic replacement, with 67 (90.5%) requiring a removal of the primary endoprosthesis. By severity, all complications were divided into 5 types. Infections were the most frequent complications of knee replacement resulting in revision surgery (19 cases, 25.7% of all revision operations). Conclusion. Improvement of oncological systems quality lead to the decrease in the rate of revision surgery due to mechanical reasons. However, the complication rate after knee replacement remains higher than after conventional arthroplasty
Изучение диагностической ценности реакции непрямой гемагглютинации в сравнении с иммуноферментным анализом и другими серологическими тестами при бруцеллезе крупного рогатого скота
The results of comparative brucellosis diagnostic studies of blood sera from cattle at farms with different epizootic situations, performed in 2021 in the laboratory of the Caspian Zonal Research Veterinary Institute – a branch of the Dagestan Agriculture Science Centre, are presented in the paper. The diagnostic efficiency of the indirect hemagglutination test (IHA) was studied in comparison with enzyme immunoassay (ELISA), agglutination test (RA), complement fixation test (CFR), rose-bengal test (RBP) and immunodiffusion reaction with O-PS antigen (RID with O-PS antigen). The specificity of these serological tests was confirmed by the negative results of studies of 40 samples of blood serum of non-vaccinated against brucellosis animals at a brucellosis-safe farm. The sensitivity of the tested diagnostic tools was determined using 46 blood serum samples from cows immunized with the B. abortus 82 vaccine at a brucellosis-prone farm. According to the results obtained, in particular, according to a significant percentage of animals positively reacting to brucellosis in RID with O-PS antigen and high titers of RNHA, RA and RSK, it can be stated that the infection in the herd proceeds in an acute form. Thus, positive results were obtained in RNGA in the study of 18 (39.1%), ELISA (LLC NPF “Sibbiotest”) – 29 (63 %), in RSK – 18 (39.1 %), in RA – 15 (32.6 %), RBP – 15 (32.6 %) and RID with O-PS antigen – 7 (15.2 %) blood serum samples. The conducted studies have shown that RNHA is one of the most sensitive tests, which makes it possible to detect a high percentage of animals with brucellosis at a brucellosis-prone farm (39.1% of those studied) in the early stages after infection and surpasses the results of most other serological methods. The results of comparative serological studies of blood serum samples of cattle in RNHA, IEA, RSK, RA, RBP and RID with O-PS confirmed the specificity of the tests and the high sensitivity of RNHA with brucellosis erythrocyte antigen.Представлены результаты сравнительных диагностических исследований сывороток крови крупного рогатого скота на бруцеллез из хозяйств с различной эпизоотической ситуацией, выполненных в 2021 г. в лаборатории Прикаспийского зонального НИВИ – филиале ФГБНУ «ФАНЦ РД». Изучена диагностическая эффективность реакции непрямой гемагглютинации (РНГА) в сравнении с иммуноферментным анализом (ИФА), реакцией агглютинации (РА), реакцией связывания комплемента (РСК), роз-бенгал пробой (РБП) и реакцией иммунодиффузии с О-ПС антигеном (РИД с О-ПС антигеном). Специфичность указанных серологических тестов подтверждена отрицательными результатами исследований 40 проб сыворотки крови невакцинированных против бруцеллеза животных из благополучного хозяйства. Определение чувствительности испытуемых средств диагностики выполнено с использованием 46 проб сыворотки крови коров, иммунизированных вакциной из штамма B. abortus 82, из неблагополучного по бруцеллезу хозяйства. Согласно полученным результатам, в частности по значительному проценту положительно реагирующих на бруцеллез животных в РИД с О-ПС антигеном и высоким титрам РНГА, РА и РСК, можно утверждать, что инфекция в стаде протекает в острой форме. Так, положительные результаты в РНГА были получены при исследовании 18 (39,1 %) проб сыворотки крови, в ИФА (ООО НПФ «Сиббиотест») – 29 (63 %), в РСК – 18 (39,1 %), в РА – 15 (32,6 %), в РБП – 15 (32,6 %) и РИД с О-ПС антигеном – 7 (15,2 %) проб сыворотки крови. Проведенные исследования показали, что РНГА является одним из наиболее чувствительных тестов, позволяющим выявить в неблагополучном хозяйстве высокий процент больных бруцеллезом животных (39,1 % к исследованным) в ранние сроки после инфицирования, и превосходит результаты большинства других серологических методов. Результаты сравнительных серологических исследований проб сыворотки крови крупного рогатого скота в РНГА, ИФА, РСК, РА, РБП и РИД с О-ПС антигеном подтвердили специфичность тестов и высокую чувствительность РНГА с антигеном бруцеллезным эритроцитарным
Electronic properties and phase transitions in low-dimensional semiconductors
We present the first review of the current state of the literature on
electronic properties and phase transitions in TlX and TlMX2 (M = Ga, In; X =
Se, S, Te) compounds. These chalcogenides belong to a family of the
low-dimensional semiconductors possessing chain or layered structure. They are
of significant interest because of their highly anisotropic properties, semi-
and photoconductivity, non-linear effects in their I-V characteristics
(including a region of negative differential resistance), switching and memory
effects, second harmonic optical generation, relaxor behavior and potential
applications for optoelectronic devices. We review the crystal structure of TlX
and TlMX2 compounds, their transport properties under ambient conditions,
experimental and theoretical studies of the electronic structure, transport
properties and semiconductor-metal phase transitions under high pressure, and
sequences of temperature-induced structural phase transitions with intermediate
incommensurate states. Electronic nature of the ferroelectric phase transitions
in the above-mentioned compounds, as well as relaxor behavior, nanodomains and
possible occurrence of quantum dots in doped and irradiated crystals is
discussed.Comment: 70 pages, 38 figure