Some Isoperimetric Inequalities in Electrochemistry and Hele Shaw Flows

Isoperimetric inequalities are applied to a moving-boundaryproblem for doubly-connected domains. This problem occurs forexample in electrochemistry, in which case the domains in questionare the electrolyte of an electrolytic cell. The two electrodessurrounding the electrolyte are assumed to grow or dissolve,at different rates in general, by electrochemical reaction.We obtain optimal estimates showing, for example, that the leastchange in volume of each electrode always occurs in sphericalsymmetry.     

Non-parametric identification of non-linear oscillating systems

The problem of system identification from a time series of measurements is solved by using non-parametric additive models. Having only few structural information about the system, a non-parametric approach may be more appropriate than a parametric one for which detailed prior knowledge is needed. Based on non-parametric regression, the functions in the additive models are estimated by a penalized least-squares approach using backfitting. The optimal smoothing parameters are determined via generalized cross-validation, making this approach completely adaptive to the data. The procedure is applied to identify the non-linear restoring force of vibrationally excited helical wire rope isolators.     

Stochastic global optimization methods part II: Multi level methods

In Part II of our paper, two stochastic methods for global optimization are described that, with probability 1, find all relevant local minima of the objective function with the smallest possible number of local searches. The computational performance of these methods is examined both analytically and empirically.     

Stereoselective total synthesis of aminoiminohexitols via carbamate annulation

New methodology for the preparation of a variety of aminoiminohextitols is described. Key in the synthesis is the application of a diastereoselective Strecker reaction and the extension of our carbamate annulation methodology to protected and functionalized alkenylamines. Insight into the effects that the substitution patterns of the alkenylamines have on the diastereoselectivity of the iodocyclization and carbamate annulation is discussed. An evaluation of the glycosidase inhibitory activity of the aminoiminohexitols and derivatives is also presented, with the previously undisclosed D-talo isomer showing good selective inhibition of β-D-glucosidase.     

Die PrÄmienanpassungsautomatik in der Krankenversicherung

Blätter der DGVFM - Die PrÄmienanpassungsautomatik in der deutschen privaten Krankenversicherung wurde aus einer Notlage heraus entwickelt. Diese Notlage war durch den immensen Anstieg...     

Identifiability and observability analysis for experimental design in nonlinear dynamical models

Dynamical models of cellular processes promise to yield new insights into the underlying systems and their biological interpretation. The processes are usually nonlinear, high dimensional, and time-resolved experimental data of the processes are sparse. Therefore, parameter estimation faces the challenges of structural and practical nonidentifiability. Nonidentifiability of parameters induces nonobservability of trajectories, reducing the predictive power of the model. We will discuss a generic approach for nonlinear models that allows for identifiability and observability analysis by means of a realistic example from systems biology. The results will be utilized to design new experiments that enhance model predictiveness, illustrating the iterative cycle between modeling and experimentation in systems biology.     

Lipid length and iso-branching of trehalose diesters influences Mincle agonist activity

We report on the efficient synthesis of linear trehalose diesters (TDEs) and iso-branched TDEs (maradolipids or iso-TDEs) and their ability to activate bone marrow-derived macrophages (BMDMs) as determined by cytokine (IL-1β, IL-12, IL-6, IL-10) and chemokine (MIP-2) production. Both classes of TDEs were found to activate BMDMs in a Mincle-dependent manner, with longer-chain (≥C18) lipids leading to a robust inflammatory response. On the whole, the iso-branched TDEs led to greater cytokine production and a faster immune response when compared to their linear counterparts. Moreover, C12-TDE and iso-C12-TDE elicited the production of MIP-2 by BMDMs, thereby providing the first example of TDEs with a chain length of ≤ C12 leading to a Mincle-dependent immune response and one that is less inflammatory in nature.     

On‐Surface Domino Reactions: Glaser Coupling and Dehydrogenative Coupling of a Biscarboxylic Acid To Form Polymeric Bisacylperoxides

Herein we report the on‐surface oxidative homocoupling of 6,6′‐(1,4‐buta‐1,3‐diynyl)bis(2‐naphthoic acid) (BDNA) via bisacylperoxide formation on different Au substrates. By using this unprecedented dehydrogenative polymerization of a biscarboxylic acid, linear poly‐BDNA with a chain length of over 100 nm was prepared. It is shown that the monomer BDNA can be prepared in situ at the surface via on‐surface Glaser coupling of 6‐ethynyl‐2‐naphthoic acid (ENA). Under the Glaser coupling conditions, BDNA directly undergoes polymerization to give the polymeric peroxide (poly‐BDNA) representing a first example of an on‐surface domino reaction. It is shown that the reaction outcome varies as a function of surface topography (Au(111) or Au(100)) and also of the surface coverage, to give branched polymers, linear polymers, or 2D metal–organic networks.     

Jahn-Teller distortion,ferromagnetic coupling,and electron delocalization in a high-spin Fe–Fe bonded dimer

Fe₂(N,N’-diphenylformamidinate)₄, 1, first synthesized in 1994, is one of very few non-organometallic compounds with Fe–Fe distances, (2.46 Å) suggestive of an Fe–Fe bond. The electronic structure of 1 has been unclear because of its distorted D₂ geometry, as well as its reported S = 4 ground state. Computational investigations using DFT methods have shown that the D₂ geometry is the result of a Jahn-Teller distortion away from D₄ symmetry, in which the ground state would be orbitally degenerate. Broken symmetry methods have shown that ferromagnetic coupling between the two high-spin Fe(II) ions in 1 is a consequence of spin delocalization caused by a three-electron σ bond and a weaker three-electron δ bond between the Fe atoms. The relationship between ferromagnetic coupling and an Fe–Fe bond is established from results using hybrid functionals having variable amounts of Hartree-Fock exchange, which is found, surprisingly, to mitigate Fe–Fe bonding.