Superconductive superheating field for finiteκ

We have calculated analytically the superheating fieldH _sh for bulk superconductors, correct to second order in. We find , which agrees well with numerical computations for<0.5. The surface order parameter is , and the penetration depth is .     

Imine hydrogenation catalyzed by iridium complexes comprising monodentate chiral phosphoramidites and N-donor ligands

The relatively inexpensive chiral monodentate phosphoramidite (S)-MONOPHOS may be used in combination with pyridines to prepare iridium complexes effective for catalysis of asymmetric imine hydrogenation with comparable enantioselectivity to some of those containing more costly chiral bidentate phosphines. [Ir(cod)((S)-MONOPHOS)(L)]BArF (cod = 1,5-cyclooctadiene; L = 3-methylisoquinoline, acridine, 2,6-lutidine, acetonitrile, or 2,3,3-trimethylindolenine; BArF = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) are efficient catalysts for the asymmetric hydrogenation of 2,3,3-trimethylindolenine. An important observation is that the catalyst containing acridine is more enantioselective than the catalyst derived from 2,3,3-trimethylindolenine which suggests that the other N-donor ligands are not readily displaced by the substrate during the catalytic cycle.     

Approximate density matrices and wigner distribution functions from density,kinetic energy density,and idempotency constraints

The Wigner distribution function and the corresponding density matrix are calculated using a form for the distribution function suggested by maximization of the entropy. Wigner functions and density matrices are determined by imposing conditions of idempotency on the density matrix. Exchange energies and Compton profiles calculated from density matrices obtained by imposing the idempotency constraints are compared with the results of calculations using the Hartree–Fock density matrix and a Gaussian approximation for the density matrix for H and the noble gases He through Xe. Compton profiles from Wigner functions with idempotency constraints show improvements over the Gaussian approximation for the lighter atoms, but do not show significant changes for the heavier atoms. Exchange energies from density matrices with idempotency constraints show improvements over the Gaussian approximation except for the heavier atoms Kr and Xe.     

Solution of the Hartree–Fock problem by expansion onto nested bases

A method for solving the Hartree–Fock problem in a finite basis set is derived, which permits each orbital to be expanded in a different basis. If the basis set for each orbital ?_i contains the basis functions for the preceding orbitals, ?_i?1, ?_i?2,… ?₁, then the ?_i form an orthonormal set. One advantage over the standard Hartree–Fock method is that a different long range behavior for each orbital, as for example is required in the Hartree–Fock-Slater method, can be forced. A calculation on the ground state of beryllium is performed using the nested procedure. Very little energy is lost because of nesting, and the node in the 1s orbital disappears.     

The bootstrap: Some large sample theory and connections with robustness

The bootstrap, discussed by Efron (1979, 1981), is a powerful tool for the nonparametric estimation of sampling distributions and asymptotic standard errors. We demonstrate consistency of the bootstrap distribution estimates for a general class of robust differentiable statistical functionals. Our conditions for consistency of the bootstrap are variants of previously considered criteria for robustness of the associated statistics. A general example shows that, for almost any location statistic, consistency of the bootstrap variance estimator requires a tail condition on the distribution from which samples are taken. A modification of Efron's estimator of standard error is shown to circumvent this problem.     

Zur Bestimmung des Gesamt-Kohlenstoffs in Kohlen und Bodenarten

Ohne Zusammenfassung     

Zur Bestimmung der Halogene, des Phosphors und Arsens in organischen Substanzen

Ohne Zusammenfassung     

Message Passing and Metabolism

Active inference is an increasingly prominent paradigm in theoretical biology. It frames the dynamics of living systems as if they were solving an inference problem. This rests upon their flow towards some (non-equilibrium) steady state—or equivalently, their maximisation of the Bayesian model evidence for an implicit probabilistic model. For many models, these self-evidencing dynamics manifest as messages passed among elements of a system. Such messages resemble synaptic communication at a neuronal network level but could also apply to other network structures. This paper attempts to apply the same formulation to biochemical networks. The chemical computation that occurs in regulation of metabolism relies upon sparse interactions between coupled reactions, where enzymes induce conditional dependencies between reactants. We will see that these reactions may be viewed as the movement of probability mass between alternative categorical states. When framed in this way, the master equations describing such systems can be reformulated in terms of their steady-state distribution. This distribution plays the role of a generative model, affording an inferential interpretation of the underlying biochemistry. Finally, we see that—in analogy with computational neurology and psychiatry—metabolic disorders may be characterized as false inference under aberrant prior beliefs.     

Label free capacitive immunosensor for detecting calpastatin — A meat tenderness biomarker

An immunological capacitive biosensor for calpastatin was developed, optimized and applied for the analysis of meat extract samples. Anti-calpastatin antibody was immobilized on a gold electrode modified with a self-assembled monolayer of mercaptoundecanoic acid and Protein A from Staphylococcus aureus, and the obtained immunosensor was inserted as the working electrode in an electrochemical cell of a flow injection system. The dynamic range of the sensor was 20 to 160 ng/mL calpastatin. The electrode could be regenerated and re-used for more than 7 days with minimal reduction in sensitivity. For the analysis of real samples, the target analyte was extracted from the Longissimus dorsi muscle from beef carcasses directly after slaughtering. The extract was analyzed both with the developed immunosensor and microtiter plate ELISA, and a good correlation was obtained. However the immunosensor offers advantages of speed, simplicity, sensitivity and possibility for miniaturization over conventional assays for calpastatin quantification.     

Magnesium-stabilised transition metal formyl complexes: structures,bonding, and ethenediolate formation

Herein we report the first comprehensive series of crystallographically characterised transition metal formyl complexes. In these complexes, the formyl ligand is trapped as part of a chelating structure between a transition metal (Cr, Mn, Fe, Co, Rh, W, and Ir) and a magnesium (Mg) cation. Calculations suggest that this bonding mode results in significant oxycarbene-character of the formyl ligand. Further reaction of a heterometallic Cr–Mg formyl complex results in a rare example of C–C coupling and formation of an ethenediolate complex. DFT calculations support a key role for the formyl-intermediate in ethenediolate formation. These results show that well-defined transition metal formyl complexes are potential intermediates in the homologation of carbon monoxide.

Herein we report a comprehensive series of crystallographically characterised transition metal formyl complexes.