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Medicinal leeches (Hirudo verbana Carena, 1820) used in veterinary medicine, human medicine and pharmacology, are currently bred artificially at bio-factories. The technology of leech culture as a component of aquaculture biotechnics is based on the method of accelerated growth of leeches due to intensive feeding, which allows you to get high-quality products in a fairly short time (8-10 months). Nevertheless, the problem of assessing the physiological status of raised individuals upon artificial reproduction remains not fully addressed. The findings we present herein for the first time allow us to suggest that the age-specific amino acid composition of tissues can be used to assess the physiological state and well-being of medicinal leeches in nature and in aquaculture. The aim of the work is to study the age-dependent content of the free amino acids in the tissues of medicinal leeches artificially bred in aquaculture. Studies were conducted in 2012 on the leech (Hirudo verbana Carena, 1820) individuals without signs of diseases which were purchased at the biofactory International Center for Medicinal Leeches (Moscow Province, p. Udelnaya). Leeches were kept in the laboratory in glass vessels with dechlorinated water at 20-22 oC and fed once a month with fresh bovine blood from healthy animals. The experimental specimens of H. verbana was: 5 days (newborn filaments, 0+), 1, 3, 5, 7 and 9 months old, with an average body weight of 0.029, 0.09, 0.25, 0.61, 1.33 and 1.81 g, respectively. Newborn individuals served as a control. The concentration of free amino acids (AA) in the skin and muscle tissue was determined on the analyzer AAA-339M (Mikrotechna, Czech Republic). A total of 105 leech specimens were used, 30 bioassays were prepared, and 660 element determinations were performed. The amino acid composition of the tissues of medicinal leeches H. verbana was represented by 23 AA and their derivatives. The dominant AA with an antioxidant orientation, regardless of age, were glutamine and glutamic acid, alanine, valine, leucine, and glycine, the total content of which was 65 % in filaments, and 58 % in 9-month — old individuals of the total fund AA. In the tissues of medicinal leeches, as well as in warm-blooded animals, the full composition of essential amino acids (EAA) was revealed: threonine, valine, lysine, leucine, isoleucine, histidine, arginine, methionine, phenylalanine, tryptophan. With age, the total concentrations of free amino acids decreased (r = -0.98 at p = 0.000), due to a sharp decrease in the content of arginine (24.0-fold), proline (13.4- fold), isoleucine (12.2- fold), glycine (8.5- fold), lysine (6.8- fold), histidine (6.6-fold), leucine (5.2-fold), ornithine (4.0- fold), glutamic acid and glutamine (3.8-fold), and alanine (2.9-fold). At the age of 5, 7 and 9 months, leeches had a trace content of secondary metabolites: taurine, citrulline and tryptophan (p < 0.001). However, the amino acid balance of nitrogen and protein metabolism was not disturbed, since the ratio of essential / non-essential AА did not change significantly and was 0.60 in newborn filaments, 0.73 — in 9-month-old leeches. It was found that the growth and development of H. verbana was accompanied by a significant decrease in the indicator of maturity (glycine/alanine) from 0.75 (newborn filaments) to 0.25 (9 months). The information available in the literature and the data of our research allow us to put forward the concept of using functional amino acids as biomarkers in the development of the scientific bases of technologies for the industrial breeding of these amphibionts.

We present new data of the comparison of the geographical variability of heavy metal concentrations (Cu, Zn, Mn, Fe, Cd, Pb, Ni) in tissues of medical leeches (Hirudo medicinalis, Hirudo verbana) and in bottom deposit from places of their inhabitation in various regions of Russia and Ukraine. The geographical factor was found to have a significant impact on the elemental status of medical leeches and bottom sediments. It was shown that, irrespective of geographic and biotopic timing, both types of medicinal leeches are macroconcentrator Zn and deconcentrator Mn and Fe. A high cumulative activity of H. medicinalis and H. verbana in relation to ecotoxicants Cd, Pb and Ni in aquatic ecosystems of industrial regions was revealed. A decrease in bioaccumulation activity towards heavy metals in specimens of medical leeches living in adverse climatic conditions on the northern and eastern borders of the range is shown. The ability of leeches H. medicinalis and H. verbana to regulate the level of essential metals Mn and Zn in the body is established, while the content of Cu, Fe, Cd, Pb, Ni is determined by the concentration of these elements in the habitat (bottom sediments). A high variability of the studied parameters and the general laws of bioaccumulation activity of leeches in relation to heavy metals are caused of significant correlation with climatic and geographical features of the studied regions, and a degree of anthropogenically modified territories. It is shown that the microelemental status of leeches as a whole objectively reflects regional specificity of the ecological conditions of hydrobiocoenosises. Thus, the performed investigation can be used in monitoring actions for preservation of water resources and protection of natural biological resources of the hirudofauna.

We analyze here for the first time the plasma free amino acid profile in pond bats (Myotis dasycneme Boie, 1825) living in the boreal Ural region and exposed experimentally to low positive and near-zero temperatures during their preparation for hibernation. Pond bats were caught in their mass habitation territory in the Middle Ural near the Smolinsky cave (N 56°28’, E 61°37’) in the third decade of September 2015. Qualitatively, blood plasma in pond bats contains 21 amino acids. In a model experiment carried out on pre-hibernating animals at a regular hibernation temperature (0–2°C), the total plasma pool of free amino acids increased significantly by 42% (irrespective of sex) and reached 1561.4 ± 112.6 μmol/L (p = 0.01). Under these experimental conditions, the fraction of glucogenic amino acids rose by 34% (p = 0.01) and that of essential ones by 80% (p = 0.001). Both in control and experimentally cooled pre-hibernating animals, the plasma was found to lack tryptophan, suggesting its utilization as a substrate in the synthesis of serotonin, a biogenic amine directly involved in the maintenance of hypothermia and hypometabolism in these chiropterans.

The amino acid spectrum of blood plasma in three bat species (Myotis dasycneme, Pipistrellus nathusii, Vespertilio murinus) inhabiting the Urals has been studied for the first time. The bats were trapped in the zone of their high abundance in Chelyabinsk oblast (2013–2014). Free amino acids were determined by liquid ion exchange chromatography (a total of 384 determinations). It has been shown that the plasma amino acid spectrum consists of 22 amino acids in subadult bats of all three species, but there are species-specific differences in their concentrations. The total amino-acid pool concentration in migratory P. nathusii and V. murinus exceeds that in resident M. dasycneme by factors of 2.9 and 1.8, respectively. Migratory species are characterized by a high concentration of plasma arginine: it is six times higher in V. murinus than in M. dasycneme, and in P. nathusii arginine accounts for 25.4% of the amino acid pool. The group of glucogenic amino acids is prevalent in the blood plasma of migratory species (75% in V. murinus and 79% in P. nathusii), while in M. dasycneme the total proportion of lysine, glycine, and glutamic acid is 2.3 times lower than in P. nathusii and 1.7 lower than in V. murinus (p < 0.05). These results provide evidence for significant differences in the contents of free blood plasma amino acids between migratory and resident bat species.

The article presents the results of a new comparative analysis of free amino acids in the blood plasma of representatives of insectivorous Chiroptera (Mammalia: Vespertilionidae) in the fauna of the Ural Mountains: the pond bat (Myotis dasycneme Boie, 1825) and the parti-colored bat (Vespertilio murinus Linnaeus, 1758). This is the first study to show the species variability of free amino acids in resident and migratory species of bats from different ecosystems of the Ural Region.

The crystal structure of anhydrous K4V2O7 (I) is determined by powder X-ray diffraction. The compound crystallizes in the monoclinic system (a = 10.222(1) A, b = 6.2309(8) A, c = 7.282(1) A, β = 101.31(1)°, space group C2/m, Z = 2). The structure contains layers of isolated V2O7 pyrovanadate groups separated by layers of potassium cations. The hydration and dehydration of I are studied by thermal analysis and high-temperature X-ray diffraction. The dehydration is accompanied by decomposition of the starting crystal hydrate to give intermediate compounds. Anhydrous compound I undergoes a reversible phase transition at 740°C. The high-temperature phase is assumed to have a hexagonal unit cell (a = 6.169(4) A, c = 15.72(1) A, Z = 2).

The first tin vanadium phosphate SnVPO5 was synthesized by a solid-state reaction and characterized by X-ray single crystal diffraction and magnetic susceptibility measurements. The crystal structure of SnVPO5 ( a = 5.2633 ( 4 ) A , b = 6.5252 ( 9 ) A , c = 6.8785 ( 10 ) A , α = 113.283 ( 11 ) ° , β = 108.037 ( 9 ) ° , γ = 94.603 ( 9 ) ° , S.G. P-1, Z = 2 ) is a three-dimensional framework constructed by V2O10 units fasten together by tetrahedral phosphate groups. Tin atoms are situated in structure interstices. They have five-fold coordination arrangement due to a presence of sterically active lone pair which position was visualized by ELF calculations. The magnetic susceptibility shows a broad maximum at 22 K which is probably due to low-dimensional spin correlations. We propose that the magnetism of the compound can be understood by interacting spin-dimers on a distorted square lattice. Strong quantum fluctuations were suggested by unusual field dependence of the transition temperature and unexpectedly low Curie constant.

The structural investigation of Sn2P2O7 was carried out for the first time by means of single crystal and powder X-ray diffraction. The crystal structure of β-Sn2P2O7 pyrophosphate was solved using...

Two new complex vanadyl(IV)phosphates Na 2 M VO(PO 4 ) 2 ( M =Ca, Sr) were synthesized in evacuated quartz ampoules and investigated by means of X-ray diffraction, electron microscopy, DTA, ESR and magnetic susceptibility measurements. The crystal structure of Na 2 SrVO(PO 4 ) 2 was solved ab initio from X-ray powder diffraction data. Both compounds are isostructural: a =10.5233(3) A, b =6.5578(2) A, c =10.0536(3) A and a =10.6476(3) A, b =6.6224(2) A, c =10.2537(3) A for Ca and Sr, respectively; S.G. Pnma , Z =4. The compounds have a three-dimensional structure consisting of V 4+ O 6 octahedra connected by PO 4 tetrahedra via five of the six vertexes forming a framework with cross-like channels. The strontium and sodium atoms are located in the channels in an ordered manner. Electron diffraction as well as high-resolution electron microscopy confirmed the structure solution. The new vanadylphosphates are Curie–Weiss paramagnets in a wide temperature range down to 2 K with θ =12 and 5 K for Ca and Sr phases, respectively.

The new perovskite PbVO3 was synthesized under high-temperature and high-pressure conditions. Its crystal structure (a = 3.80005(6) A, c = 4.6703(1) A, Z = 1, S.G. P4mm) contains isolated layers of corner-shared VO5 pyramids, which are formed instead of octahedra due to a strong tetragonal distortion (c/a = 1.23). The lead atom is shifted out of the center of the unit cell toward one of two [VO2]-layers due to the influence of the lone pair. This new perovskite exhibits a semiconductor-like ρ(T) dependence down to 2 K. This behavior can be qualitatively explained by taking into account strong electron correlations in electronic structure calculations.

The crystal structure of the new oxide Pb2V5O12 was determined from X-ray single crystal and neutron powder diffraction data. The oxide is monoclinic, space group P2/c with a = 8.408(2), b = 5.017(1), c = 11.940(2) A, β = 98.42(3)°, Z = 2. The crystal structure of Pb2V5O12 consists of isolated layers formed by edge and corner sharing VO5 square pyramids with short vanadyl bonds directed above and below the layers. Six pyramids linked by corner form so-called “tiling plaquettes”. Neighboring plaquettes are linked by edge sharing. The Pb cations are located in the interstitial positions between layers. The structure of Pb2V5O12 is closely related to the MVO2n+1 homologous series known for Ca, Sr and Cd. Electron diffraction and high resolution electrom microscopy study confirm the crystal structure data and revealed a phase transition induced by irradiation resulting in the formation of a disordered orthorhombic phase (a ≈ 3.75, b ≈ 3.79, c ≈ 5.03 A) which corresponds to a sublattice of the plaquette-built structure. The analyses of related structures allowed to suggest a more general formula for this homologous series: MmVm+nO3m+2n. The structures of such compounds may be described by shear planes formed by a shift of the VO2 units over a 1/2* [110] translation starting from the parent “VO2” or “MVO3” structures. Magnetic susceptibility measurements of Pb2V5O12 indicate low dimensional behavior and a strong antiferromagnetic exchange within the plaquettes with J of the order of 190 K. Anomalies observed in the susceptibility and the specific heat indicate magnetic order at TN = 26 K. Kristallstruktur und magnetische Eigenschaften von Pb2V5O12 Die Kristallstruktur von Pb2V5O12 wurde mittels Einkristall-Rontgen- und Neutronen-Pulverdiffraktometrie bestimmt. Das Oxid ist monoklin mit den Gitterparametern a = 8.408(2), b = 5.017(1), c = 11.940(2) A, β = 98.42(3)°, Raumgruppe P2/c, Z = 2. Die Struktur von Pb2V5O12 wird durch Schichten von VO5-Pyramiden gebildet, die uber Ecken und Kanten miteinander verknupft sind und deren kurze Vanadyl-Bindungen senkrecht zur Ebene liegen. Sechs Pyramiden bilden jeweils eine Plakette. Benachbarte Plaketten sind ziegelartig angeordnet und uber Kanten miteinander verbunden. Das Pb-Kation sitzt in den Zwischengitterplatzen und trennt die Pyramiden-Schichten voneinander. Die Struktur von Pb2V5O12 ist eng verwandt mit den Strukturen der Verbindungsserie MVO2n+1, die fur M = Ca, Sr und Cd bekannt sind. Untersuchungen mit Elektronen-Streuung und hochaufgeloster Elektronenbeugung bestatigen die Struktur und zeigen einen durch Bestrahlung induzierten Phasenubergang. Dieser fuhrt zur Bildung einer gestorten rhombischen Phase mit a ≈ 3.75, b ≈ 3.79, c ≈ 5.03 A, deren Struktur einem Plaketten-Untergitter entspricht. Eine Analyse der verwandten Strukturen legt die allgemeine Formel MmVm+nO3m+2n fur diese Verbindungsserie nahe. Messungen der magnetischen Suszeptibilitat zeigen niederdimensionales Verhalten und eine starke magnetische Kopplung innerhalb der Plaketten, mit einer Kopplungskonstante J ≅ 190 K. Anomalien in der spezifischen Warme und in der magnetischen Suszeptibilitat deuten auf einen antiferromagnetischen Phasenubergang bei TN = 26 K.

The new complex vanadium oxide K 2 SrV 3 O 9 has been synthesized and investigated by means of X-ray powder diffraction (XPD), electron microscopy and magnetic susceptibility measurements. The oxide has an orthorhombic unit cell with lattice parameters a = 10.1922(2) A, b = 5.4171(1) A, c = 16.1425(3) A, space group Pnma and Z = 4. The crystal structure of K 2 SrV 3 O 9 has been refined by Rietveld method using X-ray powder diffraction data. The structure contains infinite chains built by V 4+ O 5 square pyramids linked to each other via VO 4 tetrahedra. The chains form layers and potassium and strontium cations orderly occupy structural interstices between these layers. Electron diffraction as well as high resolution electron microscopy confirmed the structure solution. Magnetic susceptibility measurements revealed an antiferromagnetic interaction with J of the order of 100 K inside the chains and no long-range magnetic order above 2 K. The origin of the magnetic exchange is likely a result of super-exchange interaction through the two VO 4 tetrahedra linking the polyhedra with the magnetic V 4+ cations.

The new complex oxide Na 2 SrV 3 O 9 was synthesized and investigated by means of X-ray diffraction, electron microscopy and magnetic susceptibility measurements. This oxide has a monoclinic unit cell with parameters a =5.416(1) A, b =15.040(3) A, c =10.051(2) A, β =97.03(3)°, space group P 2 1 / c and Z =4. The crystal structure of Na 2 SrV 3 O 9 , as determined from X-ray single-crystal data, is built up from isolated chains formed by square V 4+ O 5 pyramids. Neighboring pyramids are linked by two bridging V 5+ O 4 tetrahedra sharing a corner with each pyramid. The Na and Sr atoms are situated between the chains. Electron diffraction and HREM investigations confirmed the crystal structure. The temperature dependence of the susceptibility indicates low-dimensional magnetic behavior with a sizeable strength of the magnetic intra-chain exchange J of the order of 80 K, which is very likely due to superexchange through the two VO 4 tetrahedra linking the magnetic V 4+ cations.

The crystal structure of the new oxide Pb2V5O12 was determined from X-ray single crystal and neutron powder diffraction data. The oxide is monoclinic, space group P2/c with a = 8.408(2), b = 5.017(1), c = 11.940(2) A, β = 98.42(3)°, Z = 2. The crystal structure of Pb2V5O12 consists of isolated layers formed by edge and corner sharing VO5 square pyramids with short vanadyl bonds directed above and below the layers. Six pyramids linked by corner form so-called “tiling plaquettes”. Neighboring plaquettes are linked by edge sharing. The Pb cations are located in the interstitial positions between layers. The structure of Pb2V5O12 is closely related to the MVO2n+1 homologous series known for Ca, Sr and Cd. Electron diffraction and high resolution electrom microscopy study confirm the crystal structure data and revealed a phase transition induced by irradiation resulting in the formation of a disordered orthorhombic phase (a ≈ 3.75, b ≈ 3.79, c ≈ 5.03 A) which corresponds to a sublattice of the plaquette-built structure. The analyses of related structures allowed to suggest a more general formula for this homologous series: MmVm+nO3m+2n. The structures of such compounds may be described by shear planes formed by a shift of the VO2 units over a 1/2* [110] translation starting from the parent “VO2” or “MVO3” structures. Magnetic susceptibility measurements of Pb2V5O12 indicate low dimensional behavior and a strong antiferromagnetic exchange within the plaquettes with J of the order of 190 K. Anomalies observed in the susceptibility and the specific heat indicate magnetic order at TN = 26 K. Kristallstruktur und magnetische Eigenschaften von Pb2V5O12 Die Kristallstruktur von Pb2V5O12 wurde mittels Einkristall-Rontgen- und Neutronen-Pulverdiffraktometrie bestimmt. Das Oxid ist monoklin mit den Gitterparametern a = 8.408(2), b = 5.017(1), c = 11.940(2) A, β = 98.42(3)°, Raumgruppe P2/c, Z = 2. Die Struktur von Pb2V5O12 wird durch Schichten von VO5-Pyramiden gebildet, die uber Ecken und Kanten miteinander verknupft sind und deren kurze Vanadyl-Bindungen senkrecht zur Ebene liegen. Sechs Pyramiden bilden jeweils eine Plakette. Benachbarte Plaketten sind ziegelartig angeordnet und uber Kanten miteinander verbunden. Das Pb-Kation sitzt in den Zwischengitterplatzen und trennt die Pyramiden-Schichten voneinander. Die Struktur von Pb2V5O12 ist eng verwandt mit den Strukturen der Verbindungsserie MVO2n+1, die fur M = Ca, Sr und Cd bekannt sind. Untersuchungen mit Elektronen-Streuung und hochaufgeloster Elektronenbeugung bestatigen die Struktur und zeigen einen durch Bestrahlung induzierten Phasenubergang. Dieser fuhrt zur Bildung einer gestorten rhombischen Phase mit a ≈ 3.75, b ≈ 3.79, c ≈ 5.03 A, deren Struktur einem Plaketten-Untergitter entspricht. Eine Analyse der verwandten Strukturen legt die allgemeine Formel MmVm+nO3m+2n fur diese Verbindungsserie nahe. Messungen der magnetischen Suszeptibilitat zeigen niederdimensionales Verhalten und eine starke magnetische Kopplung innerhalb der Plaketten, mit einer Kopplungskonstante J ≅ 190 K. Anomalien in der spezifischen Warme und in der magnetischen Suszeptibilitat deuten auf einen antiferromagnetischen Phasenubergang bei TN = 26 K.

CONTENTS I. Introduction 167 II. Reduction of the glass point in polymers by plasticising 167 III. Reduction of the tendency of polymers to crystallise 169