Notes on rabbinic epitaphs: I

Jüdische Grabsteinepigraphik: R. Yosef Trani (1568-1639), R. Akiva Eger (d. 1837), R. David Hoffmann (d. 1921

Correspondence between many-particle excitations and the entanglement spectrum of disordered ballistic one-dimensional systems

Using exact diagonalization for non-interacting systems and density matrix renormalization group for interacting systems we show that Li and Haldane's conjecture on the correspondence between the low-lying many-particle excitation spectrum and the entanglement spectrum holds for disordered ballistic one-dimensional many-particle systems. In order to demonstrate the correspondence we develop a computational efficient way to calculate the ES of low-excitation of non-interacting systems. We observe and explain the presence of an unexpected shell structure in the excitation structure. The low-lying shell are robust and survive even for strong electron-electron interactions.Comment: 6 pages 4 figure

Purjehtimisesta ja yhteyden kokemuksesta

Kirjoitus on osa "Elämän peruskysymykset – Anssi Peräkylän 60-vuotisjuhlakirja" –kirja

Modeling the architecture of depolymerase-containing receptor binding proteins in Klebsiella phages

Klebsiella pneumoniae carries a thick polysaccharide capsule. This highly variable chemical structure plays an important role in its virulence. Many Klebsiella bacteriophages recognize this capsule with a receptor binding protein (RBP) that contains a depolymerase domain. This domain degrades the capsule to initiate phage infection. RBPs are highly specific and thus largely determine the host spectrum of the phage. A majority of known Klebsiella phages have only one or two RBPs, but phages with up to 11 RBPs with depolymerase activity and a broad host spectrum have been identified. A detailed bioinformatic analysis shows that similar RBP domains repeatedly occur in K. pneumoniae phages with structural RBP domains for attachment of an RBP to the phage tail (anchor domain) or for branching of RBPs (T4gp10-like domain). Structural domains determining the RBP architecture are located at the N-terminus, while the depolymerase is located in the center of protein. Occasionally, the RBP is complemented with an autocleavable chaperone domain at the distal end serving for folding and multimerization. The enzymatic domain is subjected to an intense horizontal transfer to rapidly shift the phage host spectrum without affecting the RBP architecture. These analyses allowed to model a set of conserved RBP architectures, indicating evolutionary linkages