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The trophic relationships between bats (Chiroptera) and Lake Baikal biota have been assessed based on microscopic studies of Myotis petax feces (n = 22). From 82 to 86% of samples had fragments of exoskeletons of caddis flies (Trichoptera) and dipterans (Diptera). These taxa include mainly aquatic and semiaquatic species. Many species from these taxa are endemic to Lake Baikal. Terrestrial insects are found in studied samples less frequently (Hymenoptera 41%, Neuroptera 27%, and Heteroptera 9%). Morphological analysis has revealed fragments of Baikal amphipods in two fecal samples of M. pretax. Further molecular studies will make it possible to detect greater invertebrate taxa diversity in fecal samples of bats feeding near Lake Baikal. [ABSTRACT FROM AUTHOR]

Background and aim: Pneumonia remains one of the most frequent death causes worldwide. Among the etiological factors S. pneumoniae-causing lobar pneumonia plays a leading role. According to current textbook knowledge at least three sequential stages of lobar pneumonia are distinguished: congestion, red hepatization and gray hepatization. However, there are no detailed data supporting this stage concept. There are also controversial views on its etiology. In this study, the lung changes in lobar pneumonia were related to the cause and duration of the disease. In addition, the complications of the disease were evaluated. PCR studies verified the etiology of pneumonia. Material and methods: Lobar pneumonia was analyzed in 252 post mortem cases examined in a large hospital in Irkutsk. The pathology, etiology of pneumonia, course of disease and cause of death were recorded and correlated to its clinical course and duration. In the second part of the study, the results in 95 patients were analyzed in detail and related to PCR findings. Results: Most patients were adult men of low social status who showed signs of severe alcoholism. Lobar pneumonia was observed in 85% of the patients, while the remaining patients showed sublobar ("lobular", focal) lung involvement. Histologically, three patterns of inflammation were observed, which in most patients occurred concurrently in different parts of the involved lobe: "congestion", characterized by serous exudation with multiple cocci (41% of cases), "red hepatization" (41% of cases) and "gray hepatization" (100% of cases). The latter pattern was subdivided into three subgroups according to the ratio of fibrin—neutrophils and the presence of macrophages. The mean number of different histological patterns observed per patient was 3.8. There was no correlation between the inflammatory patterns and the duration of the disease. In 23% of the patients, the cause of death was of pulmonary origin, while the remaining patients died of extrapulmonary complications (i.e. acute heart failure 26%, acute vascular insufficiency 15% purulent meningitis 11–24.3%. In 29/95 patients (20 with lobar and 9 with focal pneumonia) pneumococcal etiology of pneumonia was established by PCR. Conclusion: Lobar pneumonia is a distinct clinico-pathological entity caused by S. pneumoniae, demonstrated by PCR testing and/or cytological examinations. Bacteriologic studies frequently give falsenegative results. Lobar pneumonia is characterized by three main histopathological patterns (congestion or microbeous edema, and red and gray hepatization) which usually occur side by side and not in chronological order. Early death is often related to heart failure and septic shock, while meningitis is a frequent complication later in the course. [ABSTRACT FROM AUTHOR]

The phenomenon of the trawling insectivorous eastern bat Myotis petax Hollister 1912 feeding on the Baikal pelagic amphipod Macrohectopus branickii (Dybowsky 1874), which migrate to the water surface at night, is reported. The accumulation of large numbers of M. branickii was observed in the upper water layer near a steep underwater slope. The bats touched the water surface and captured the amphipods at the moment of their contact with the water–air interface. These trophic relationships between pelagic organisms and terrestrial vertebrates complement the food net in the ecosystem of Lake Baikal, an ancient deep lake. [ABSTRACT FROM AUTHOR]

Abstract: A virological study of 642 samples including biological material from enterovirus infection (EVI) patients and wastewater from the sewage treatment plants of Irkutsk has been performed in cultured RD cells. Eighty-six strains were isolated in 2011 and 2014 and subsequently identified by a neutralization test (NT) with type-specific sera. A molecular genetic approach was used to confirm the composition of the circulating enterovirus (EV) group and identify virus strains. Nucleotide sequences of the VP1 gene fragment were determined and analyzed for 43 EV strains. EVs were divided into two groups: viruses endemic for the region (ECHO6, ECHO11, and Coxsackie B4) and imported from China (Coxsackie A4, enterovirus type 71 (EV71), and Coxsackie B5). Genetic variants of EV not encountered previously in Irkutsk oblast (Coxsackie A4 and EV71) have been identified. The dominant role of ECHO6, Coxsackie B4, and Coxsackie B5 as causative agents of EVI in Irkutsk oblast in 2011 and 2014 has been established. [ABSTRACT FROM AUTHOR]

We consider LS-, LAD-, R-, M-, S-, LMS-, LTS-, MM-, and HBR-estimates for the parameters of a linear regression model with unknown noise distribution. With computer modeling for medium sized samples, we compare the accuracy of the considered estimates for the most popular probability distributions of noise in a regression model. For different noise distributions, we analytically compute asymptotic efficiencies of LS-, LAD-, R-, M-, S-, and LTS- estimates. We give recommendations for practical applications of these methods for different noise distributions in the model. We show examples on real datasets that support the advantages of robust estimates. [ABSTRACT FROM AUTHOR]