The Genome of a Pathogenic Rhodococcus: Cooptive Virulence Underpinned by Key Gene Acquisitions

We report the genome of the facultative intracellular parasite Rhodococcus equi, the only animal pathogen within the biotechnologically important actinobacterial genus Rhodococcus. The 5.0-Mb R. equi 103S genome is significantly smaller than those of environmental rhodococci. This is due to genome expansion in nonpathogenic species, via a linear gain of paralogous genes and an accelerated genetic flux, rather than reductive evolution in R. equi. The 103S genome lacks the extensive catabolic and secondary metabolic complement of environmental rhodococci, and it displays unique adaptations for host colonization and competition in the short-chain fatty acid–rich intestine and manure of herbivores—two main R. equi reservoirs. Except for a few horizontally acquired (HGT) pathogenicity loci, including a cytoadhesive pilus determinant (rpl) and the virulence plasmid vap pathogenicity island (PAI) required for intramacrophage survival, most of the potential virulence-associated genes identified in R. equi are conserved in environmental rhodococci or have homologs in nonpathogenic Actinobacteria. This suggests a mechanism of virulence evolution based on the cooption of existing core actinobacterial traits, triggered by key host niche–adaptive HGT events. We tested this hypothesis by investigating R. equi virulence plasmid-chromosome crosstalk, by global transcription profiling and expression network analysis. Two chromosomal genes conserved in environmental rhodococci, encoding putative chorismate mutase and anthranilate synthase enzymes involved in aromatic amino acid biosynthesis, were strongly coregulated with vap PAI virulence genes and required for optimal proliferation in macrophages. The regulatory integration of chromosomal metabolic genes under the control of the HGT–acquired plasmid PAI is thus an important element in the cooptive virulence of R. equi

polymorphs under high pressure

Total energy calculations based on density functional theory are performed for HgSe in the ambient and pressure induced phases. The electronic exchange and correlation effects are described by employing the generalized gradient approximation together with the projector augmented wave potentials. The equation of state parameters and the phase transition paths are obtained from the energy- volume landscape and enthalpy versus pressure data, correspondingly. The observed phase transition sequence of HgSe as ZB -> Cinnabar -> RS -> Cmcm and the final transition from Cmcm to CsCl structure predicted by the other theoretical study are confirmed by our calculations. The pressure dependence of elastic constants of the structures considered in this study is reported. Bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and Debye temperature as isotropic mechanical properties are evaluated for HgSe polymorphs. Our calculations of energy band structure reveal the inverted band structure evoking that HgSe in ZB phase is a semimetal. (c) 2018 Elsevier B. V. All rights reserved

Comparison of Levitation Forces of Bulk MgB2 Superconductors Produced by Nano Boron and Carbon-Doped Nano Boron

Celik, Sukru/0000-0002-6918-7569; DUZ, Ismahan/0000-0002-2298-232X; GUNER, SAIT BARIS/0000-0001-7487-4817; HOSSAIN, MD Shahriar/0000-0002-7291-9281; Ozturk, Kemal/0000-0002-8847-1880WOS: 000343162400010MgB2 bulk superconductors were prepared by hot press plus furnace heating method. Two types of boron powders were used, one is amorphous nano boron and the other is C-doped boron. Characteristics of superconductors were determined by XRD and resistance measurements. Systematic levitation force measurements were performed by using a modular system at low temperatures. These bulk superconductors showed around 9 N repulsive and 4 N attractive forces in the z-axis at 20 K at closest point to the cryostat lid which contains the MgB2 superconductor. These values slightly decreased by increasing temperature to 24 and 28 K for both samples. Comparing two samples, nano boron MgB2 showed slightly higher levitation force than C-doped MgB2 although C-doped MgB2 has higher attractive force value at the closest point. This situation points out that C-doped MgB2 is much proper for attractive force applications (as guidance force) while the nanoboron MgB2 sample is much appropriate for repulsive force (as levitation)

Pace yearbook of international law

MgB bulk superconductors were prepared by hot press plus furnace heating method. Two types of boron powders were used, one is amorphous nano boron and the other is C-doped boron. Characteristics of superconductors were determined by XRD and resistance measurements. Systematic levitation force measurements were performed by using a modular system at low temperatures. These bulk superconductors showed around 9 N repulsive and 4 N attractive forces in the z-axis at 20 K at closest point to the cryostat lid which contains the MgB superconductor. These values slightly decreased by increasing temperature to 24 and 28 K for both samples. Comparing two samples, nano boron MgB showed slightly higher levitation force than C-doped MgB although C-doped MgB has higher attractive force value at the closest point. This situation points out that C-doped MgB is much proper for attractive force applications (as guidance force) while the nanoboron MgB sample is much appropriate for repulsive force (as levitation)

Porous composite prosthetic pylon for integration with skin and bone

This article presents results of the further development and testing of the skin and bone integrated pylon (SBIP-1) for percutaneous (through skin) connection of the residual bone with an external limb prosthesis. We investigated a composite structure (called the SBIP-2) made of titanium particles and fine wires using mathematical modeling and mechanical testing. Results showed that the strength of the pylon was comparable with that of anatomical bone. In vitro and in vivo animal studies on 30 rats showed that the reinforcement of the composite pylon did not compromise its previously shown capacity for inviting skin and bone cell ingrowth through the device. These findings provide evidence for the safe and reliable long-term percutaneous transfer of vital and therapeutic substances, signals, and necessary forces and moments from a prosthetic device to the body