Host Taxon Predictor : a tool for predicting taxon of the host of a newly discovered virus

Abstract Recent advances in metagenomics provided a valuable alternative to culture-based approaches for better sampling viral diversity. However, some of newly identified viruses lack sequence similarity to any of previously sequenced ones, and cannot be easily assigned to their hosts. Here we present a bioinformatic approach to this problem. We developed classifiers capable of distinguishing eukaryotic viruses from the phages achieving almost 95% prediction accuracy. The classifiers are wrapped in Host Taxon Predictor (HTP) software written in Python which is freely available at https://github.com/wojciech-galan/viruses_classifier. HTP’s performance was later demonstrated on a collection of newly identified viral genomes and genome fragments. In summary, HTP is a culture- and alignment-free approach for distinction between phages and eukaryotic viruses. We have also shown that it is possible to further extend our method to go up the evolutionary tree and predict whether a virus can infect narrower taxa

Poly[aqua­(μ-pyrazine-2-carboxyl­ato-κ3 N,O:O)(μ-pyrazine-2-carboxyl­ato-κ3 N,O:O′)lead(II)]

The polymeric structure of the title compound, [Pb(C5H3N2O2)2(H2O)]n, is built up from centrosymmetric [Pb(C5H3N2O2)2(H2O)]2 dimers, which are bridged by ligand carboxyl­ate O atoms. The PbII ion adopts an irregular PbN2O5 coordination polyhedron; it is chelated by one N,O-bidentate ligand and also bonds to a water O atom. A second N,O-bidentate ligand forms the dimer bridge and another bridging O atom from a nearby dimer also bonds to the PbII ion, leading to layers propagating in (100). A network of O—H⋯O hydrogen bonds operates between water O atoms (donors) and carboxyl­ate O atoms (acceptors)

catena-Poly[[bis­(μ-3-amino­pyrazine-2-carboxyl­ato)-κ3 N 1,O:O;κ3 O:N 1,O)dilithium]-di-μ-aqua]

The title compound, [Li(C5H4N3O2)(H2O)]n, is composed of centrosymmetric dinuclear units, in which the LiI ions are bridged by two carboxyl­ate O atoms donated by two ligands. The dinuclear unit is nearly planar [r.m.s. deviation = 0.0125 (2) Å]. The LiI ion is coordinated by an N,O-chelating ligand, a bridging carboxyl­ate O atom from another ligand and two bridging water O atoms in a distorted trigonal-bipyra­midal geometry. The water O atoms bridge the dinuclear units into a polymeric mol­ecular column along [010]. The columns are held together by O—H⋯O and N—H⋯N hydrogen bonds. An intra­molecular N—H⋯O inter­action also occurs

catena-Poly[[(diaqua­zinc)-μ-3-carb­oxy­pyrazine-2-carboxyl­ato-κ4 N 1,O 2;N 4,O 3] nitrate]

The crystal structure of the title compound, {[Zn(C6H3N2O4)(H2O)2]NO3}n, is built of zigzag cationic chains propagating in [010] with nitrate anions located in the space between the chains. The ZnII ion is coordinated by N and O atoms of two symmetry-related ligands in equatorial sites, and by two water O atoms at the axial sites of a distorted octa­hedron. One carboxyl­ate group of the ligand remains protonated, serving as a donor in a short intra­molecular O—H⋯O hydrogen bond. The coordinated water mol­ecules are donors and the nitrate O atoms act as acceptors in a network of O—H⋯O hydrogen bonds

Effect of semiconductor element substitution on the electric properties of barium titanate ceramics

The investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition of the synthesized material. The dielectric properties of the ceramics were also determined within the temperature range (ΔT=130-500K). It was found that the substitution of Si+4 ions had a significant influence on temperature behavior of the real (ϵ′) and imaginary (ϵ″) parts of electric permittivity as well as the temperature dependence of a.c. conductivity. Temperature regions of PTCR effect (positive temperature coefficient of resistivity) were determined for BTSi04 ceramics in the vicinity of structural phase transitions typical for barium titanate. No distinct maximum indicating a low-temperature structural transition to a rhombohedral phase in BTSi04 was found. The activation energy of conductivity was determined from the Arrhenius plots. It was found that substitution of Si ions in amount of 4wt.% caused almost 50% decrease in an activation energy value

Assessment of ship manoeuvring safety in waterway systems by relative navigational risk

The safety of vessels navigating in the sea waterway system is ensured by fulfilling the acceptable restrictions called safe ship operation conditions in that system. The assessment of navigation safety is particularly important when the conditions for safe operation of ships in the waterway system are changed concerns increasing the maximum parameters of vessels, increasing the allowable hydrometeorological conditions or changing the minimum tug assistance. The article presents a method for assessing navigation safety when the conditions for the safe operation of vessels in the waterway system get changed. The method uses two indicators, which are difference in navigation risks and relative navigation risk. To determine the navigational risk, algorithms were developed for calculating the probability of accidents caused by the deterioration of navigation conditions and technical failure of ship equipment and tugs. Another algorithm was developed for calculating the consequences of the accidents that involve blocking a waterway by a ship anchoring in an emergency, grounding, impact of the ship against a port structure or moored ship and a collision with another ship in motion. The method developed for assessing navigation safety by means of relative navigation risk can be used in practice when changing the conditions for safe operation of vessels in the waterway system and when the system is modernized. Navigational safety management is a decision process that is implemented in the loop presented in the article. The acceptable risk is determined on the basis of vessel traffic intensity and ship parameters defined by safe operation conditions for a given waterway system. Relative navigational risk may be used in assessment and comparison of various conditions of safe ship operation. The probability of an accident caused by ship's moving outside the available navigable area due to technical failures of ship equipment or tugs is determined, depending on the type of port waterway and the manoeuvres performed

catena-Poly[[(6-carb­oxy­pyrazine-2-carboxyl­ato)lithium]-μ-aqua]

The asymmetric unit of the title compound, [Li(C6H3N2O4)(H2O)]n, contains an LiI ion with a distorted trigonal–bipyramidal coordination environment. It is chelated by a singly protonated ligand mol­ecule via its heterocyclic N atom, by two O aoms, each donated by an adjacent carboxyl­ate group, and is further coordinated by a water O atom which acts as a bridge, forming a mol­ecular ribbon. A proton attached to one of the carboxyl­ate O atoms is situated on an inversion centre and forms a short centrosymmetric hydrogen bond, generating mol­ecular layers parallel to the ac plane. These layers are held together by weak O—H⋯O hydrogen bonds in which the coordinated water mol­ecules act as donors, whereas carboxyl­ate O atoms are acceptors

Zmiany w postawie ciała u dzieci w pierwszych trzech latach nauki szkolnej

Okres między 6. a 10. rż. sprzyja pogarszaniu się postawy ciała z powodu nowych warunków związanych z obowiązkiem szkolnym. O ile wśród dzieci 6-letnich przed rozpoczęciem nauki szkolnej postawa bardzo dobra i dobra występuje w 41,47%, to już w wieku 10 lat taką postawę ma tylko 26,83% badanych. Może to być wynikiem nagłego obowiązku siedzenia długi czas w ławce szkolnej, często niedostosowanej do wzrostu dziecka (te same ławki od I do III klasy), noszenia zbyt ciężkiego tornistra względem wagi dziecka, a także zbyt małej ilości ruchu ukierunkowanego na prawidłową postawę. Forum Medycyny Rodzinnej 2010, tom 4, nr 4, 287-29

Poly[di-μ-aqua-μ4-(pyrazine-2,5-dicarboxyl­ato)-dilithium(I)]

In the title coordination polymer, [Li2(C6H2N2O2)(H2O)2]n the pyrazine-2,5-dicarboxyl­ate dianionic ligand bridges two symmetry-independent Li+ ions using both its N,O-chelating sites. The carboxyl­ate O atom of one of them also bridges to another Li+ ion, while the second O atom of this group is bonded to another Li+ ion. Two symmetry-independent water O atoms participate also in the bridging system, which gives rise to a polymeric three-dimensional framework. Both Li+ ions show distorted trigonal–bipyramidal LiNO4 coordination geometries, with the N atom in an axial site in both cases. The packing is consolidated by O—H⋯O hydrogen bonds, which occur between water mol­ecules as donors and carboxyl­ate O atoms as acceptors

Influence of cation order on the dielectric properties of (1 - x)Pb(Sc0:5Nb0:5)O3-xPb(Yb0:5Nb0:5)O3ceramics

Ceramic lead niobates and their solid solutions (1 - x)Pb(Sc0:5Nb0:5)O3 - xPb(Yb0:5Nb0:5)O3 were synthesized by solid state reactions from oxides. The structure of investigated samples was characterized by X-ray diffraction (XRD). Dielectric studies of the ceramics were performed by means of broadband dielectric spectroscopy at the temperature ranging from 600 K to 140 K. For all ceramic samples a diffuse phase transition as well as relaxor ferroelectric behavior were observed. © 2020 Barbara Garbarz-Glos et al., published by Sciendo 2020. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2