[my]-Bis(diphenylphosphanyl)borato-[kappa]2P:P'-bis[dicarbonyl([eta]5-cyclopentadienyl)iron(II)] tetrachloridoferrate(III) chloroform solvate

The title compound, [Fe2(C5H5)2(C24H22BP2)(CO)4][FeCl4]·CHCl3, is an oxidation product of CpFe(CO)2PPh2BH3. One pair of phenyl rings attached to the two different P atoms are almost parallel, as are the other pair [dihedral angles = 8.7 (5) and 8.9 (5)°]. The planes of the two cyclopentadienyl rings are inclined by 26.8 (7)° with respect to each other. The carbonyl groups at each Fe atom are almost perpendicular [C-Fe-C = 92.6 (6) and 94.3 (5)°]. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.019 Å; R factor = 0.112; wR factor = 0.177; data-to-parameter ratio = 16.8

Genus Two Modular Bootstrap

We study the Virasoro conformal block decomposition of the genus two partition function of a two-dimensional CFT by expanding around a Z3-invariant Riemann surface that is a three-fold cover of the Riemann sphere branched at four points, and explore constraints from genus two modular invariance and unitarity. In particular, we find 'critical surfaces' that constrain the structure constants of a CFT beyond what is accessible via the crossing equation on the sphere.Comment: 23 pages, 6 figures. v2: updated references, typos corrected. v3-v5: minor typos correcte

Mutation of H63 and its Catalytic Affect on the Methionine Aminopeptidase from \u3cem\u3eEscherichia coli\u3c/em\u3e

In order to gain insight into the mechanistic role of a flexible exterior loop near the active site, made up of Y62, H63, G64, and Y65, that has been proposed to play an important role in substrate binding and recognition in the methionyl aminopeptidase from Escherichia coli (EcMetAP-I), the H63A enzyme was prepared. Mutation of H63 to alanine does not affect the ability of the enzyme to bind divalent metal ions. The specific activity of H63A EcMetAP-I was determined using four different substrates of varying lengths, namely, l-Met-p-NA, MAS, MGMM and MSSHRWDW. For the smallest/shortest substrate (l-Met-p-NA) the specific activity decreased nearly seven fold but as the peptide length increased, the specific activity also increased and became comparable to WT EcMetAP-I. This decrease in specific activity is primarily due to a decrease in the observed kcat values, which decreases nearly sixty-fold for l-Met-p-NA while only a four-fold decrease is observed for the tri- and tetra-peptide substrates. Interestingly, no change in kcat was observed when the octa-peptide MSSHRWDW was used as a substrate. These data suggest that H63 affects the hydrolysis of small peptide substrates whereas large peptides can overcome the observed loss in binding energy, as predicted from Km values, by additional hydrophilic and hydrophobic interactions

Sustainability of public finances and automatic stabilisation under a rule of budgetary discipline

This paper addresses the question of how a fiscal rule of a general type can preserve the sustainability of public finances and provide automatic stabilisation, taking as given interest rates and price stability. This issue can be considered complementary to the analysis of monetary policy rules, whose targets are price stability and often also output stabilisation, assuming that fiscal policy guarantees the sustainability of public finances. Considering the institutional framework provided by the Stability and Growth Pact, the paper also draws some policy conclusions. JEL Classification: E61, H62, H63

Extension theory for elliptic partial differential operators with pseudodifferential methods

This is a short survey on the connection between general extension theories and the study of realizations of elliptic operators A on smooth domains in R^n, n > 1. The theory of pseudodifferential boundary problems has turned out to be very useful here, not only as a formulational framework, but also for the solution of specific questions. We recall some elements of that theory, and show its application in several cases (including recent results), namely to the lower boundedness question, and the question of spectral asymptotics for differences between resolvents.Comment: 26 pages, style changed to LaTeX, new material added at the end, to appear in the Lecture Notes Series of the London Math. Soc. published by Cambridge Univ. Pres