Simplicial gauge theory and quantum gauge theory simulation

We propose a general formulation of simplicial lattice gauge theory inspired by the finite element method. Numerical tests of convergence towards continuum results are performed for several SU(2) gauge fields. Additionally, we perform simplicial Monte Carlo quantum gauge field simulations involving measurements of the action as well as differently sized Wilson loops as functions of β.     

The effect of trace additions of copper and pretreatment conditions on the filiform corrosion of powder-coated aluminium alloy AA6060

This paper presents a short review of the literature data and the newest studies of filiform corrosion (FFC) testing of profiles extruded using a recycling-friendly AA 6xxx aluminium alloy, with Cu content up to 0.09 wt%. As the pretreatment plays a significant role in avoiding FFC on powder-coated aluminium profiles, the profiles were pretreated and coated at three different production sites. They have been tested at 40°C, 82% RH for 1000 hours (according to modified ISO 4623-2). It was observed that differences in FFC behaviour of the same type of profile coated at different plants were more significant than differences between samples with increasing Cu content. In order to understand the differences between profiles coated at different sites, GDOES analysis of samples was performed, specially focusing on surface enrichment of copper through the pretreatment.     

Prominence and control: the weighted rich-club effect

Complex systems are often characterized by large-scale hierarchical organizations. Whether the prominent elements, at the top of the hierarchy, share and control resources or avoid one another lies at the heart of a system's global organization and functioning. Inspired by network perspectives, we propose a new general framework for studying the tendency of prominent elements to form clubs with exclusive control over the majority of a system's resources. We explore associations between prominence and control in the fields of transportation, scientific collaboration, and online communication.     

Formation of optically active chromanes by catalytic asymmetric tandem oxa-Michael addition-Friedel-Crafts alkylation reactions

A novel tandem reaction involving an oxa-Michael addition, followed by a Friedel-Crafts alkylation has been developed. This catalytic tandem reaction, which provides facile and efficient access to optically active functionalised chromanes, proceeds under the influence of bisoxazoline-based catalysts to give diastereomerically pure products in enantioselectivities up to 81% and excellent yields. The optimisation studies, the scope of the reaction, and a model that on the basis of PM3 calculations predicts the outcome of the reaction will be detailed.     

Intramolecular hydrogen atom abstraction with an eight-membered cyclic transition state in open-chain aliphatic aminium radicals

Hydrogen abstraction by the nitrogen in long-chain aliphatic gas-phase aminium radicals (amine molecular ions) takes place via six-, seven-, and eight-membered cyclic transition states. The subsequent fragmentation is particularly facile after eight-membered ring hydrogen transfer.     

Convergence of lattice gauge theory for Maxwell’s equations

In this article we prove convergence of Lattice Gauge Theory in the energy norm for electromagnetism, which corresponds to gauge group U(1). This is done by stability analysis and comparison with the classical Yee-scheme which is convergent.     

Simplicial gauge theory on spacetime

We define a discrete gauge-invariant Yang–Mills–Higgs action on spacetime cylindrical meshes with simplicial spatial base. The formulation is a generalization of classical lattice gauge theory, and we prove consistency of the action in the finite element sense. In addition, we perform numerical tests of convergence towards exact continuum results for several choices of gauge fields in pure gauge theory.     

Precautions to improve the accuracy of quantitative determinations of biomarkers in clinical diagnostics

Although protein biomarkers have a great potential as biomarkers for diagnosis of diseases, they are seldom used in hospitals. There are many reasons for this, for instance, the difficulties to (i) find a biomarker for which the concentration in body fluids clearly differs between patients and healthy subjects, (ii) attain purification of the biomarker close to 100%, which is required for production of conventional protein antibodies as well as artificial gel antibodies for selective capture of a biomarker, (iii) design a standard curve for rapid and accurate determination of the concentration of the biomarker in the body fluid because of adsorption of the biomarker onto vials, pipettes, etc., (iv) determine accurately the sample volume delivered by a pipette, (v) avoid polymerization of the biomarker upon storage and to decide whether it is in the form not only of monomers, but also of dimers, trimers, etc., in the native state, (vi) determine the degree of possible glycosylation and amidation of the biomarker and (vii) decide whether glycosylation and amidation positively or negatively affects the possibility to use the protein as a biomarker. In this article, we discuss in quantitative terms the difficulties (iii–vii) and how to overcome them, which also may help to overcome the difficulty (ii), which in turn minimizes difficulty (i).