Results of UBV Photoelectric Observations of the Early-Type Eclipsing Binary System XZ Cep

Results of the three-colour photoelectric observation of the close binary system XZ Cep, obtained at the Abastumani Astrophysical observatory, are presented.Comment: 23 pages, 3 figures, 1 tebl

A planetary companion around the K giant eps Corona Borealis

Aims. Our aim is to search for and study the origin of the low-amplitude and long-periodic radial velocity (RV) variations in K giants. Methods. We present high-resolution RV measurements of K2 giant epsilon CrB from February 2005 to January 2012 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at the Bohyunsan Optical Astronomy Observatory (BOAO). Results. We find that the RV measurements for epsilon CrB exhibit a periodic variation of 417.9 +/- 0.5 days with a semi-amplitude of 129.4 +/- 2.0 m/s. There is no correlation between RV measurements and chromospheric activity in the Ca II H region, the Hipparcos photometry, or bisector velocity span. Conclusions. Keplerian motion is the most likely explanation, with the RV variations arising from an orbital motion. Assuming a possible stellar mass of 1.7 +/- 0.1 M_Sun for epsilon CrB, we obtain a minimum mass for the planetary companion of 6.7 +/- 0.3 M_Jup with an orbital semi-major axis of 1.3 AU and eccentricity of 0.11. We also discuss the implications of our observations for stellar metallicity versus planet occurrence rate and stellar mass versus planetary mass relations.Comment: 5 pages, 7 figures, 3 tables, accepted for publisation in Astronomy & Astrophysic

CoRoT photometry and high-resolution spectroscopy of the interacting eclipsing binary AU Mon

Analyses of very accurate CoRoT space photometry, past Johnson V photoelectric photometry and high-resolution \'echelle spectra led to the determination of improved and consistent fundamental stellar properties of both components of AU Mon. We derived new, accurate ephemerides for both the orbital motion (with a period of 11.113d) and the long-term, overall brightness variation (with a period of 416.9d) of this strongly interacting Be + G semi-detached binary. It is shown that this long-term variation must be due to attenuation of the total light by some variable circumbinary material. We derived the binary mass ratio $M_{\rm G}/M_{\rm B}$ = 0.17\p0.03 based on the assumption that the G-type secondary fills its Roche lobe and rotates synchronously. Using this value of the mass ratio as well as the radial velocities of the G-star, we obtained a consistent light curve model and improved estimates of the stellar masses, radii, luminosities and effective temperatures. We demonstrate that the observed lines of the B-type primary may not be of photospheric origin. We also discover rapid and periodic light changes visible in the high-quality residual CoRoT light curves. AU Mon is put into perspective by a comparison with known binaries exhibiting long-term cyclic light changes.Comment: Accepted for publication in MNRA

Identification of novel Coxiella burnetii genotypes from Ethiopian ticks

Background: Coxiella burnetii , the etiologic agent of Q fever, is a highly infectious zoonotic bacterium. Genetic information about the strains of this worldwide distributed agent circulating on the African continent is limited. The aim of the present study was the genetic characterization of C. burnetii DNA samples detected in ticks collected from Ethiopian cattle and their comparison with other genotypes found previously in other parts of the world. Methodology/Principal Findings: A total of 296 tick samples were screened by real-time PCR targeting the IS 1111 region of C. burnetii genome and from the 32 positive samples, 8 cases with sufficient C. burnetii DNA load ( Amblyomma cohaerens ,n 5 6; A. variegatum ,n 5 2) were characterized by multispacer sequence typing (MST) and multiple-locus variable-number tandem repeat analysis (MLVA). One novel sequence type (ST), the proposed ST52, was identified by MST. The MLVA-6 discriminated the proposed ST52 into two newly identified MLVA genotypes: type 24 or AH was detected in both Amblyomma species while type 26 or AI was found only in A. cohaerens . Conclusions/Significance: Both the MST and MLVA genotypes of the present work are closely related to previously described genotypes found primarily in cattle samples from different parts of the globe. This finding is congruent with the source hosts of the analyzed Ethiopian ticks, as these were also collected from cattle. The present study provides genotype information of C. burnetii from this seldom studied East-African region as well as further evidence for the presumed host-specific adaptation of this agent

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

Detection of the 128 day radial velocity variations in the supergiant {\alpha} Persei. Rotational modulations, pulsations, or a planet?

Aims. In order to search for and study the nature of the low-amplitude and long-periodic radial velocity (RV) variations of massive stars, we have been carrying out a precise RV survey for supergiants that lie near or inside the Cepheid instability strip. Methods. We have obtained high-resolution spectra of {\alpha} Per (F5 Ib) from November 2005 to September 2011 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at Bohyunsan Optical Astronomy Observatory (BOAO). Results. Our measurements reveal that {\alpha} Per shows a periodic RV variation of 128 days and a semi-amplitude of 70 m/s. We find no strong correlation between RV variations and bisector velocity span (BVS), but the 128-d peak is indeed present in the BVS variations among several other significant peaks in periodogram. Conclusions. {\alpha} Per may have an exoplanet, but the combined data spanning over 20 years seem to suggest that the 128-d RV variations have not been stable on long-term scale, which is somewhat difficult to reconcile with the exoplanet explanation. We do not exclude the pulsational nature of the 128-d variations in {\alpha} Per. Although we do not find clear evidence for surface activity or rotational modulations by spots, coupled with the fact that the expected rotation period is ~ 130 days the rotational modulation seems to be the most likely cause of the RV variations. More observational data and research are needed to clearly determine the origin of RV the variations in {\alpha} Per.Comment: 7 pages, 10 figures, 4 table

A Novel Obligate Intracellular Gamma-Proteobacterium Associated with Ixodid Ticks, Diplorickettsia massiliensis, Gen. Nov., Sp. Nov

Background: Obligate intracellular bacteria of arthropods often exhibit a significant role in either human health or arthropod ecology. Methodology/Principal Findings: An obligate intracellular gamma-proteobacterium was isolated from the actively questing hard tick Ixodes ricinus using mammalian and amphibian cell lines. Transmission electron microscopy revealed a unique morphology of the bacterium, including intravacuolar localization of bacteria grouped predominantly in pairs and internal structures composed of electron-dense crystal-like structures and regular multilayer sheath-like structures. The isolate 20B was characterized to determine its taxonomic position using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that this strain belongs to the family Coxiellaceae, order Legionellales of Gamma-proteobacteria, and the closest relatives are different Rickettsiella spp. The level of 16S rRNA gene sequence similarity between strain 20B and other recognized species of the family was below 94.5%. Partial sequences of the rpoB, parC and ftsY genes confirmed the phylogenetic position of the new isolate. The G+C content estimated on the basis of whole genome analysis of strain 20B was 37.88%. On the basis of its phenotypic and genotypic properties, together with phylogenetic distinctiveness, we propose that strain 20B to be classified in the new genus Diplorickettsia as the type strain of a novel species named Diplorickettsia massiliensis sp. nov. Conclusions/Significance: Considering the source of its isolation (hard tick, often biting humans) the role of this bacterium in the pathology of humans, animals and ticks should be further investigated

Multispacer Sequence Typing for Mycobacterium tuberculosis Genotyping

Background: Genotyping methods developed to survey the transmission dynamics of Mycobacterium tuberculosis currently rely on the interpretation of restriction and amplification profiles. Multispacer sequence typing (MST) genotyping is based on the sequencing of several intergenic regions selected after complete genome sequence analysis. It has been applied to various pathogens, but not to M. tuberculosis. Methods and Findings: In M. tuberculosis, the MST approach yielded eight variable intergenic spacers which included four previously described variable number tandem repeat loci, one single nucleotide polymorphism locus and three newly evaluated spacers. Spacer sequence stability was evaluated by serial subculture. The eight spacers were sequenced in a collection of 101 M. tuberculosis strains from five phylogeographical lineages, and yielded 29 genetic events including 13 tandem repeat number variations (44.82%), 11 single nucleotide mutations (37.93%) and 5 deletions (17.24%). These 29 genetic events yielded 32 spacer alleles or spacer-types (ST) with an index of discrimination of 0.95. The distribution of M. tuberculosis isolates into ST profiles correlated with their assignment into phylogeographical lineages. Blind comparison of a further 93 M. tuberculosis strains by MST and restriction fragment length polymorphism-IS6110 fingerprinting and mycobacterial interspersed repetitive units typing, yielded an index of discrimination of 0.961 and 0.992, respectively. MST yielded 41 different profiles delineating 16 related groups and proved to be more discriminatory than IS6110-based typing for isolates containing M<8 IS6110 copies (P<0.0003). MST was successfully applied to 7/10 clinical specimens exhibiting a Cts <= 42 cycles in internal transcribed spacer-real time PCR. Conclusions: These results support MST as an alternative, sequencing-based method for genotyping low IS6110 copy-number M. tuberculosis strains. The M. tuberculosis MST database is freely available (http://ifr48.timone.univ-mrs.fr/MST_MTuberculosis/mst)

Coxiella burnetii in Humans and Ticks in Rural Senegal

Q fever is a zoonotic disease known since 1937. The disease may be severe, causing pneumonia, hepatitis and endocarditis. Q fever agent has been described as a possible biological weapon. Animals—especially domestic cows, goats and sheep—are considered reservoirs for this infection. They are capable of sustaining the infection for long periods and excreting viable bacteria, infecting other animals and, occasionally, humans. Here we studied the distribution of Q fever in a poorly studied region, Senegal. We studied the agent of Q fever both in ticks parasitizing domestic animals and in humans (antibodies in serum, bacteria in feces, saliva and milk). We found from the studied regions the bacterium is highly prevalent in rural Senegal. Up to 37.6% of five different and most prevalent tick species may carry the bacterium. Humans living in such areas, as other mammals, may occasionally excrete Q fever agent through feces and milk

Coxiella burnetii, the Agent of Q Fever, Replicates within Trophoblasts and Induces a Unique Transcriptional Response

Q fever is a zoonosis caused by Coxiella burnetii, an obligate intracellular bacterium typically found in myeloid cells. The infection is a source of severe obstetrical complications in humans and cattle and can undergo chronic evolution in a minority of pregnant women. Because C. burnetii is found in the placentas of aborted fetuses, we investigated the possibility that it could infect trophoblasts. Here, we show that C. burnetii infected and replicated in BeWo trophoblasts within phagolysosomes. Using pangenomic microarrays, we found that C. burnetii induced a specific transcriptomic program. This program was associated with the modulation of inflammatory responses that were shared with inflammatory agonists, such as TNF, and more specific responses involving genes related to pregnancy development, including EGR-1 and NDGR1. In addition, C. burnetii stimulated gene networks organized around the IL-6 and IL-13 pathways, which both modulate STAT3. Taken together, these results revealed that trophoblasts represent a protective niche for C. burnetii. The activation program induced by C. burnetii in trophoblasts may allow bacterial replication but seems unable to interfere with the development of normal pregnancy. Such pathophysiologocal processes should require the activation of immune placental cells associated with trophoblasts