Phytocenosis biodiversity at various water levels in mesotrophic Lake Arakhley, Lake Baikal basin, Russia

Small lakes have lower water levels during dry years as was the case in 2000–2020. We sought to show the biodiversity of plant communities at various water levels in Lake Arakhley. Changes in moisture content are reflected in the cyclical variations of the water level in the lake, which decreased approximately 2 m in 2017–2018. These variations affect the biological diversity of the aquatic ecosystems. We present the latest data on the state of the plant communities in this mesotrophic lake located in the drainage basin of Lake Baikal. Lake Arakhley is a freshwater lake with low mineral content and a sodium hydrocarbonate chemical composition. Changes in the nutrient concentration were related to precipitation; inflow volume and organic matter were autochtonous at low water levels. The most diverse groups of phytoplankton found in the lake were Bacillariophyta, Chlorophyta, and Chrysophyta. High biodiversity values indicate the complexity and richness of the lake’s phytoplankton community. A prevalence of Lindavia comta was observed when water levels were low and Asterionella formosa dominated in high-water years. The maximum growth depth of lacustrine vegetation decreased from 11.0 m to 4.0 m from 1967 to 2018. Decreasing water levels were accompanied by a reduction in the littoral zone, altering the communities of aquatic plants. The hydrophyte communities were monodominant in the dry years and were represented by Ceratophyllum demersum. The vegetation cover of the lake was more diverse in high-water years and variations in the lake’s water content altered the composition of biogenic substances. These changes were reflected in the lake’s phytocenosis

Late Pleistocene–Holocene environmental and cultural changes in Primorye, southern Russian Far East: A review

This article presents an analytical review of the available palaeoenvironmental and archaeological records from the southern part (ca. 42°18′–45°30′N) of Primorye spanning the last ca. 21,000 years. The outlined climate and environmental history of the coastal and continental zones of southern Primorye, based mainly on vegetation reconstructions derived from the study of fossil pollen from sedimentary deposits from various archives, is compared with the archaeological cultural sequence of the region. This shows synchronicity between several phases of climate change and cultural transition, migration and changes in population numbers and/or subsistence strategies. The pronounced warming trend during the Early Holocene (Preboreal and Boreal stages) is associated with increasing numbers of long-term camp sites of the Late Palaeolithic hunter-gatherers and a growing importance of aquatic food resources. The Holocene maximum temperature and moisture conditions during the Atlantic stage were paralleled by the emergence and flourishing of the Neolithic Rudnaya, Vetka and Boisman cultures (ca. 7.7–5.5 14C ka BP/8.5–6.2 cal ka BP). The latter was a specialised maritime forager culture distributed along the Sea of Japan coast, which likely reflects climate conditions and sea water temperatures that promoted a broad spectrum of marine food resources. Towards the end of the Atlantic stage, sea levels decreased and transformed the coastal landscape of southern Primorye, which probably contributed to the decline of the Boisman culture. At the same time, the climate started to become cooler, which is likely related to the eastward migration of Zaisanovskaya culture groups from more continental (cooler) regions to milder southern Primorye. Continuous cooling during the Subboreal was accompanied by further immigrations of Zaisanovskaya people and an increase in millet cultivation, which probably occurred in the region between ca. 4.6–4.1 14C ka BP/5.3–4.6 cal ka BP. With the emergence of the Palaeometal Epoch cultures (ca. 3.6 14C ka BP/4.0 cal ka BP), food production diversified (growing number of cultivated crops, animal husbandry) and intensified, which probably decreased the people's dependence on climatic conditions unfavourable for food procurement. However, the maximum flourishing (ca. 2.8–2.6 14C ka BP/2.9–2.6 cal ka BP) of the Palaeometal Epoch Yankovskaya culture, represented by a maximum number of documented settlement sites in Primorye's prehistoric sequence, was likely related to a coeval short phase of climate amelioration with higher air and sea water temperatures and an increased sea level, which promoted agriculture and a higher productivity of coastal waters

Palynological Research of Bohai Abrikosovsky Settlement (Primorsky Krai)

For the first time palynological research was carried out on the Abrikosovsky settlement, located in the Krounovka river valley. This site is dated back to the epoch of the Bohai state (698–926). It was determined that during its existence there were transformations of surrounding landscape associated with climatic and anthropogenic causes. Several stages of the settlement development have been defined. Pollen of cultivated, edible wild plants and industrial crops were found in the cultural layer sediments. The inhabitants of the settlement could use stalks of nettle or hemp for the production of textiles. Reed could be one of the building materials (fascine making), its phytoliths were found in the cultural layer. It was determined that one of the natural disasters was recurring strong freshets and floods in the second half of the summer

Prevalence and Genetic Diversity of Group A Rotavirus Genotypes in Moscow (2019–2020)

Group A rotavirus (RVA) infection is the leading cause of hospitalization of children under 5 years old, presenting with symptoms of acute gastroenteritis. The aim of our study was to explore the genetic diversity of RVA among patients admitted to Moscow Infectious Disease Clinical Hospital No. 1 with symptoms of acute gastroenteritis. A total of 653 samples were collected from May 2019 through March 2020. Out of them, 135 (20.67%) fecal samples were found to be positive for rotavirus antigen by ELISA. RT-PCR detected rotavirus RNA in 80 samples. Seven G-genotypes (G1, G2, G3, G4, G8, G9, and G12) and three P-genotypes (P[8], P[4], and P[6]) formed 9 different combinations. The most common combination was G9P[8]. However, for the first time in Moscow, the combination G3P[8] took second place. Moreover, all detected viruses of this combination belonged to Equine-like G3P[8] viruses that had never been detected in Russia before. The genotype G8P[8] and G9P[4] rotaviruses were also detected in Moscow for the first time. Among the studied rotaviruses, there were equal proportions of Wa and DS-1-like strains; previous studies showed that Wa-like strains accounted for the largest proportion of rotaviruses in Russia

EARLY CONGENITAL SYPHILITIC PSEUDOPARALYSIS (PARROT’S DISEASE): A CLINICAL CASE

Background. Congenital syphilis is a severe intrauterine infection which, affecting most of the organs and systems of a child, can lead to his disability. However, it is extremely difficult to suspect congenital syphilis in a child in the absence of information about prior syphilis in his mother. The article presents a case of a monosymptomatic clinical picture of early congenital syphilis.Description of the Clinical Case. At the age of 1 month, the child had hyperemia, isolated edema of the right forearm, and restriction of limb movements. He was examined by a pediatrician who suspected a fracture of the forearm bones. X-ray did not show any fracture. The situation was regarded as an allergic reaction; desensitizing therapy was prescribed during which the range of movements in the right arm slightly increased. At the age of 2 months, there was a decrease in the range of movements in the left arm. On admission, the condition was regarded as moderate one. No fever; no signs of intoxication. Skin and visible mucous membranes were not changed. Cardiopulmonary activity was satisfactory. The abdomen was palpable in all compartments, painless. The liver was enlarged 6 cm, of dense consistency. The spleen was enlarged 5 cm. Bowel and bladder functions were normal. Neurological status: the reaction to examination was adequate, emotional cry. Cranial nerves without pathology. Can see and hear. Restricted range of movements in the arms; passive movements were painful. Muscle tone in the arms was low, in the legs — closer to physiological one. Equal and brisk tendon reflexes from the arms and legs. Large fontanel 1.5[1]1.5 cm, not protruded. X-ray examination of the forearm bones showed a change in the structure of the epiphyses of both forearm bones that was common to syphilitic osteochondritis.Conclusion. The article describes the complexity of diagnosis of early congenital syphilis in a child aged 2 months in the absence of a corresponding anamnesis in his mother. The need to rule out syphilitic infection in infants with motor impairments, born from unexamined mothers, has been emphasized

Two Cases of Dengue Fever Imported from Egypt to Russia, 2017

In 2017, two cases of dengue fever were imported from Hurghada, Egypt, where dengue fever was not considered endemic, to Moscow. These cases show how emergence of dengue fever in popular resort regions on the coast of the Red Sea can spread infection to countries where it is not endemic