We obtain the Lifshitz UV completion in a specific model for z ¼ 2 Lifshitz geometries. We use a vielbein formalism which enables identification of all the sources as leading components of well-chosen bulk fields. We show that the geometry induced from the bulk onto the boundary is a novel extension of Newton-Cartan geometry with a specific torsion tensor. We explicitly compute all the vacuum expectation values (VEVs) including the boundary stress-energy tensor and their Ward identities. After using local symmetries or Ward identities the system exhibits 6+6 sources and VEVs. The Fefferman-Graham expansion exhibits, however, an additional free function which is related to an irrelevant operator whose source has been turned off. We show that this is related to a second UV completion.

For a specific action supporting z = 2 Lifshitz geometries we identify the Lifshitz UV completion by solving for the most general solution near the Lifshitz boundary. We identify all the sources as leading components of bulk fields which requires a vielbein formalism. This includes two linear combinations of the bulk gauge field and timelike vielbein where one asymptotes to the boundary timelike vielbein and the other to the boundary gauge field. The geometry induced from the bulk onto the boundary is a novel extension of Newton-Cartan geometry that we call torsional Newton-Cartan (TNC) geometry. There is a constraint on the sources but its pairing with a Ward identity allows one to reduce the variation of the on-shell action to unconstrained sources. We compute all the vevs along with their Ward identities and derive conditions for the boundary theory to admit conserved currents obtained by contracting the boundary stress-energy tensor with a TNC analogue of a conformal Killing vector. We also obtain the anisotropic Weyl anomaly that takes the form of a Hořava-Lifshitz action defined on a TNC geometry. The Fefferman-Graham expansion contains a free function that does not appear in the variation of the on-shell action. We show that this is related to an irrelevant deformation that selects between two different UV completions.

Blood coagulation factor VII is a vitamin K dependent glycoprotein which in its activated form, factor VIIa, participates in the coagulation process by activating factor X and/or factor IX in the presence of Ca2+ and tissue factor. Three types of potential posttranslational modifications exist in the human factor VIIa molecule, namely, 10 gamma-carboxylated, N-terminally located glutamic acid residues, 1 beta-hydroxylated aspartic acid residue, and 2 N-glycosylated asparagine residues. In the present study, the amino acid sequence and posttranslational modifications of recombinant factor VIIa as purified from the culture medium of a transfected baby hamster kidney cell line have been compared to human plasma factor VIIa. By use of HPLC, amino acid analysis, peptide mapping, and automated Edman degradations, the protein backbone of recombinant factor VIIa was found to be identical with human factor VIIa. Neither recombinant factor VIIa nor human plasma factor VIIa was found to contain beta-hydroxyaspartic acid. In human plasma factor VIIa, the 10 N-terminally located glutamic acid residues were found to be fully gamma-carboxylated whereas 9 full and 1 partial gamma-carboxylated residues were found in the corresponding positions of the recombinant factor VIIa molecule. Asparagine residues 145 and 322 were found to be fully N-glycosylated in human plasma factor VIIa. In the recombinant factor VIIa, asparagine residue 322 was fully glycosylated whereas asparagine residue 145 was only partially (approximately 66%) glycosylated. Besides minor differences in the sialic acid and fucose contents, the overall carbohydrate compositions were nearly identical in recombinant factor VIIa and human plasma factor VIIa.(ABSTRACT TRUNCATED AT 250 WORDS)

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In most magnetically-ordered iron pnictides, the magnetic moments lie in the FeAs planes, parallel to the modulation direction of the spin stripes. However, recent experiments in hole-doped iron pnictides have observed a reorientation of the magnetic moments from in-plane to out-of-plane. Interestingly, this reorientation is accompanied by a change in the magnetic ground state from a stripe antiferromagnet to a tetragonal non-uniform magnetic configuration. Motivated by these recent observations, here we investigate the origin of the spin anisotropy in iron pnictides using an itinerant microscopic electronic model that respects all the symmetry properties of a single FeAs plane. We find that the interplay between the spin-orbit coupling and the Hund's rule coupling can account for the observed spin anisotropies, including the spin reorientation in hole-doped pnictides, without the need to invoke orbital or nematic order. Our calculations also reveal an asymmetry between the magnetic ground states of electron-and hole-doped compounds, with only the latter displaying tetragonal magnetic states. arXiv:1508.01763v4 [cond-mat.supr-con]

We study a chain of magnetic moments exchange coupled to a conventional three dimensional superconductor. In the normal state the chain orders into a collinear configuration, while in the superconducting phase we find that ferromagnetism is unstable to the formation of a magnetic spiral state. Beyond weak exchange coupling the spiral wavevector greatly exceeds the inverse superconducting coherence length as a result of the strong spin-spin interaction mediated through the subgap band of Yu-Shiba-Rusinov states. Moreover, the simple spin-spin exchange description breaks down as the subgap band crosses the Fermi energy, wherein the spiral phase becomes stabilized by the spontaneous opening of a p−wave superconducting gap within the band. This leads to the possibility of electron-driven topological superconductivity with Majorana boundary modes using magnetic atoms on superconducting surfaces.PACS numbers: 75.30. Hx, 74.20.Mn, 03.67.Lx The prospect of performing topological quantum computation [1] has stimulated intense investigations into condensed-matter systems harboring Majorana bound states [2][3][4][5][6][7][8][9][10][11][12][13]. One potential platform involves magnetic atoms arranged in a regular lattice on an s−wave superconducting substrate [14]. This system has received a renewed interest due to recent scanning tunneling microscopy (STM) data possibly supporting the existence of Majorana bound states in a self-assembled onedimensional (1d) array of atomically-spaced Fe atoms on the surface of superconducting Pb [15][16][17].We focus on the case of an STM-assembled magnetic atom chain whose spacing is several substrate lattice sites [28], where the overlap of atomic wavefunctions is negligible. In that case each atom acts as an isolated magnetic moment giving rise to localized, sub-gap Yu-ShibaRusinov (YSR) states [20][21][22][23][24][25] within the superconductor. Overlap between YSR states leads to the formation of an effectively spinless sub-gap band that can undergo a topological superconducting transition controlled by the magnetic ordering of the magnetic atoms (spin chain) [26,27], see Fig. 1. On the other hand, the ordering of the spin chain is dictated by the indirect exchange mediated by electrons in the superconductor, allowing the possibility of an electron-driven "selforganized" topological superconducting phase.Although many important aspects of spin chains on superconductors have been theoretically studied by several authors [19,26,27,[30][31][32][33][34][35][36][37] (see also [38][39][40][41]), a generic conceptual account of the collective ordering mechanism of the magnetic and electronic degrees of freedom in a bulk (d > 1) superconductor remains elusive (the 1d case is special due to 2k F nesting and was studied in [30][31][32], see also [38]).In this paper, we establish the existence of spiral magnetic order and self-organized topological superconductivity in the case of a magnetic adatom chain on a 3d substrate using an exactly solvable minimal model. We provide the conceptual fram...

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Intestinal trefoil factor (ITF) from human (hITF) and rat (rITF) have been produced in Saccharomyces cerevisiae. The DNA encoding the two peptides were cloned by polymerase chain reactions (PCR) from a human normal colon library and a rat small intestinal epithelial cell library. Recombinant plasmids were constructed to encode a fusion protein consisting of a hybrid leader sequence and the rat and human ITF sequences, respectively. The leader sequence used serves to direct the fusion protein into the secretory (and processing) pathway of the cell. The secreted recombinant hITF was found in a monomer and a dimer form, whereas the rITF was only secreted as a dimer. The secreted peptides were purified by a combination of ionic exchange chromatography and preparative HPLC. From 8 L of yeast fermentation broth, 256 mg of hITF (monomer) and 133 mg of hITF (dimer) were isolated, and from 8.7 L of fermentation broth, 236 mg of rITF (dimer) was isolated. The structure of hITF (monomer), hITF (dimer), and rITF (dimer) was determined by amino acid analyses, peptide mapping, sequence analyses, and electrospray mass spectrometry analyses. In hITF (monomer) six of the seven cysteines are disulfide-linked to form 3 disulfide bridges. Mass analysis indicated that the last cysteine residue (Cys-57) did not exist as free (-SH) cysteine, but have reacted with cysteine to form an S-S linked cystine. Sequence and mass spectrometry analyses as well as peptide mapping showed that the dimer form of both hITF and rITF is mediated by a disulfide bridge between Cys-57 residues of two monomers.