We show that algebraically shifting a pair of simplicial complexes weakly increases their relative homology Betti numbers in every dimension. More precisely, let ∆(K) denote the algebraically shifted complex of simplicial complex K, and let β j (K, L) = dim k H j (K, L; k) be the dimension of the jth reduced relative homology group over a field k of a pair of simplicial complexes L ⊆ K. Then β ...

Association constants of a bis-(acetylguanidinium)ferrocene dication to various (di)carboxylates were determined through UV-vis titrations. Association constant values greater than 10(4) M(-1) were determined for both phthalate and maleate carboxylates to the bis-(acetylguanidinium)ferrocene salt in pure water. Density functional theory computations of the binding enthalpy of the rigid carboxyl...

The Mn(hfac)(2) complex of the paramagnetic 4-(benzoxazol-2'-yl)-1,2,3,5-dithiadiazolyl ligand is reported (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonato-). The Mn(ii) and radical ligand spins are coupled antiferromagnetically (AF) in the coordination complex. Short sulfur-oxygen contacts between molecules provide an efficient pathway for AF coupling between the radical ligand of one molecule an...

Structures of the Grb2 SH2 domain complexed with a series of pseudopeptides containing flexible (benzyl succinate) and constrained (aryl cyclopropanedicarboxylate) replacements of the phosphotyrosine (pY) residue in tripeptides derived from Ac-pYXN-NH(2) (where X = V, I, E and Q) were elucidated by X-ray crystallography. Complexes of flexible/constrained pairs having the same pY + 1 amino acid ...

To do homological algebra with unbounded chain complexes one needs to first find a way of constructing resolutions. Spaltenstein solved this problem for chain complexes of R-modules by truncating further and further to the left, resolving the pieces, and gluing back the partial resolutions. Our aim is to give a homotopy theoretical interpretation of this procedure, which may be extended to a re...

The objective of this study was to examine whether ion pair complexation with endogenous bile salts in hepatocytes contributes to the preferential biliary excretion of organic cations (OCs). Tributylmethylammonium (TBuMA; mol wt 200) and triethylmethylammonium (TEMA; mol wt 116) were selected as model OCs that exhibit significant and negligible biliary excretion, respectively, in rats. The appa...

To explore how the ion-pair in a single salt molecule evolves with the addition of water, infrared (IR) spectra of complexes composed of NaCl and multiple water molecules have been recorded for the first time. The NaCl(H2O)n complexes were formed and probed in liquid helium nanodroplets, and IR spectra were recorded for n = 1 → 4. The spectra for n = 1, 2, and 3 are consistent with formation of...

The project report entitled, “ Charge Transfer Comlexes of drugs with  acceptors” is divided into two parts. Part-I deals with the spectrophotometric studies of molecular complexes of drugs with TCNE and Paraquat and Part II deals with Ion-pair charge transfer complexes of drugs with acidic triphenylmethane dyes. Each part is further divided into 1) Introduction 2) Experimental and 3) Results ...

In the present work, the substituent effect on the strength of H-bonds in the guanine – cytosine base pair was studied when the substituents are connected to the guanine base through a phenyl ring. In this study, guanine was substituted in the H8 and H9 positions by electron donating (ED) and electron withdrawing (EW) groups mediated by a phenyl ring in the gas phase. The calculations were perf...