The fauna of the rivers of the north of Western Siberia that do not belong to the Ob’ River basin is of particular interest from the point of view of zoogeography and understanding of the processes of formation of the freshwater malacofauna. Starting in the taiga zone, these rivers flow north and cannot serve as a way of interzonal dispersal of species from lower latitudes. However, information about the fresh-water malacofauna of these river basins is poorly presented in the scientific literature, some of the published species findings are doubtful or erroneous. The gastropod mollusks of the family Valvatidae of the Taz river basin (Western Siberia) are considered. The basin is located closer to the Yenisei than to the Ob’ River basin. The study was based on original authors’ material represented by both qualitative and quantitative samples. It has been found that eight species of mollusks of the genus Valvata occurs in the water reservoirs and streams of the Taz basin, an annotated list of species is presented, and a brief zoogeographic characteristic is given. Three species (Valvata helicoidea, V. sorensis and V. korotnevi) are for the first time recorded from the basin, one of them (V. korotnevi) is for the first time recorded from the Western Siberia waterbodies.
The article is devoted to the fauna of Bivalvia (family Sphaeriidae) of waterbodies and water-courses of the eastern slope of the Polar and Pre-Polar Urals. The fauna of freshwater clams of this region remains practically unexplored. This study aimed at identification of the species content of Bivalvia and publication of images of their shells. We analyzed both qualitative and quantitative samples of molluscs as well as fish stomach contents. The identification of the material was based on conchological features, including the hinge structure. In total, 31 sphaeriid species is reported, and the annotated check-list, brief zoogeographic characteristics of the fauna, and shell images are provided. Most species demonstrate a limited spatial distribution within the studied area. The causes of discrepancies between published lists of sphaeriid species are discussed.
Ten species of halophilic gastropods of the genus Caspiohydrobia are identified for the first time from the Lantsug and Gor’kaya Rechka salt rivers, tributaries of Lakes Elton and Baskunchak, respectively. The genus was previously known from the Caspian and Aral seas and some salt water bodies of Kazakhstan and Chelyabinsk and Kurgan regions. Since the hydrological and hydrochemical regimes of salt rivers critically depend on climatic conditions, Caspiohydrobia living in these habitats can be considered endangered.
The findings of the freshwater snail endemic to the Far East from the waterbodies of Yakutsk City are described. It is shown on the basis of dissections of snails and morphometric study of their shells that there are no statistically significant differences between the males and females of .
The locations of Boreoelona contortrix in the waterbodies of Western Siberia and Kazakhstan are reported as well as the data on morphology of shells and copulatory apparatus of the species from different parts of its range. The interpopulation variation is considered. On the basis of anatomical and morphometric study, it has been shown that there are no statistically significant differences between males and females of B. contortrix. Problems of taxonomy of the Boreoelona species are discussed.
On the basis of dissections and shell measurements we studied sexual dimorphism in shell shape in Parafossarulus manchouricus taken from the bay of the Bira River (Russian Far East). It is shown that there are no statistically significant differences in shells of males and females in P. manchouricus .
The data on the fauna and distribution of Bivalvia in the Malyi Yugan River basin (Western Siberia, Tyumen Region) are provided. The aquatic malacofauna of this territory has not been studied previously. In 2013-2014, the Malyi Yugan River as well as seven its tributaries, two connected waterbodies, seven floodplain lakes and a single moraine lake have been sampled. As a results, the data on average density and biomass of bivalves in the waterbodies, a list of 49 species belonging to 4 families, and a brief zoogeographical characteristic of the fauna are provided. The malacofauna of rivers whose drainage basins are situated in swampy areas proved to be rather specific due to unusual life conditions for molluscs. Some peculiarities of behavior of molluscs in different habitats are discussed. The species composition of bivalves in sampled by us rivers drastically differs between waterbodies.
This review deals with the problem of mollusk invasions into the inland waters of the Western Siberian region. The data on all the alien species of snails and bivalves registered up to now in water bodies of the region are provided. Possible ways and mechanisms of penetration of the alien species into the Western Siberian water bodies are discussed. The most well-studied case of mollusk invasion, that of the European river snail, Viviparus viviparus (L., 1758), into water bodies of the Ob-Irtysh basin, is considered in detail. An ecological and geographical classification of the invader species is proposed. It includes three categories: (1) exotic species, (2) species belonging to the boreal European complex which regain the lost part of their range, and (3) heat-loving species of South European origin. We hypothesize that, in the foreseeable future, the inflow of the alien mollusk species to the Western Siberian inland waters will remain low owing to some physical-geographical peculiarities of this area.
The data on distribution of molluscs of the genus Digyrcidum Locard, 1882 in waterbodies of the Urals and Western Siberia are given. A new species, Digyrcidum starobogatovi Andreeva et Lazutkina, sp. nov., is described. This species inhabits waterbodies of the Urals and Western Siberia sympatrically with the species Digyrcidum bouguirgnati (Paladilhe, 1869).
The results of long-term (19732005) authors studies of the inland water gastropod of Western Siberia are given.Following to the most recent taxonomic surveys (Starobogatov et al., 2004;Kantor, Sysoev, 2005), we count 134 gastropod species belonging to nine families to dwell in the region under discussion.Most of them (86 out of 134) are pulmonates.The most diverse fauna of water snails was found in the Irtyshian zoogeographical province, and the least diverse in the Lower Obian one.There is a clear latitudinal gradient of gastropod species richness in Western Siberia.Differences in species composition between zoogeographical provinces as well as possible pathways of snails migration through Western Siberia are discussed.It was found, the gastropod fauna of Western Siberia inland waters has a European origin with a participation of autochtonous species and migrants from Eastern Siberia and Northern America.
The size of shells in some freshwater pulmonate mollusk species abundant in Western Siberia (Lymnaea fragilis, L. terebra, Planorbis planorbis, and Anisus leucostoma) is relatively large in the south and decreases in the north. It is supposed that this phenomenon is explained by the fact that the season with conditions allowing the growth of mollusks is shorter in the north than in the south of Western Siberia.
This paper describes the properties of SC cable with natural oxide on the strands developed for the UNK SC magnets and summarizes the performance of short and long magnets made of such cable. The coating was selected based on the studies of cable samples with various strand coating. Ten 1-m long dipoles and two 6-m long dipoles were manufactured using the cable with natural oxide coating of strands. These dipoles had low value of AC losses in the coil and reached the maximum magnetic field of 6.5 T in magnet aperture at the current ramp rates up to 0.8 T/s and 4.25 K temperature. The effects of interlayer splices and cable electrical insulation on the magnet ramp rate dependence are also reported.
Fermilab is involved in the development of high field superconducting accelerator magnets for different applications based on Nb3Sn superconductor. Accelerator magnets have to withstand thousands of thermal and excitation cycles, significant mechanical stresses, and high voltages developed during quench while providing reliable operation for extended period of time. Insulation system is one of the most important elements of magnet design, which determines (and in some cases even limits) the electrical, mechanical, and thermal performance. Different elements of the magnet insulation system such as cable insulation, interlayer insulation, quench heater insulation, and ground insulation have been developed and studied. In this paper we will describe the insulation system used in the Fermilab shell-type dipole models followed by the high voltage test results.