Fluorescent detection of glutamate with a dicopper(II) polyamine cage

A dicopper(II) octamine cage includes selectively the l-glutamate ion in water at pH 7, establishing Cu²⁺/-COO⁻ coordinative interactions. In particular, l-glutamate is able to displace the quenched rhodamine indicator from the cage, whose fluorescence is then fully restored. Other typical neurotransmitters (glycine, GABA) and some related amino acids are discriminated.     

Phonon spectra and structure of crystalline ethylene oxide and ethylene sulphide at 77 k

Vibrational spectra of solid ethylene oxide and ethylene sulphide were measured at 77 K. The analysis of the exciton splitting components was carried out using infrared polarized radiation. By comparing the amount of frequency separation in the IR and in the Raman spectra and the difference in the frequency values in these two spectra, an assignment is proposed which obeys the selection rules of a C_{2 h} centrosymmetric factor group for both molecules.     

High-order Levi curvatures and classification results

In this paper we write some differential formulas involving the high-order Levi curvatures of a real hypersurface in a complex space form. As application we get a classification result under suitable assumptions.     

Mechanisms and Synthetic Strategies in Visible Light-Driven [2+2]-Heterocycloadditions

The synthesis of four membered heterocycles usually requires multi-step procedures and prefunctionalized reactants. A straightforward alternative is the photochemical [2+2]-heterocycloaddition between an alkene and a carbonyl derivative, conventionally based on the photoexcitation of this latter. However, this approach is limited by the absorption profile of the carbonyl, requiring in most of the cases the use of high-energy UV-light, that often results in undesired side reactions and/or the degradation of the reaction components. The development of new and milder visible light-driven [2+2]-heterocycloadditions is, therefore, highly desirable. In this Review, we highlight the most relevant achievements in the development of [2+2]-heterocycloadditions promoted by visible light, with a particular emphasis on the involved reaction mechanisms. The open challenges will also be discussed, suggesting new possible evolutions, and stimulating new methodological developments in the field.     

A parameter-free unconstrained reformulation for nonsmooth problems with convex constraints

Computational Optimization and Applications - In the present paper we propose to rewrite a nonsmooth problem subjected to convex constraints as an unconstrained problem. We show that this novel...     

Some Ideals with Large Projective Dimension

For an ideal in a polynomial ring over a field, a monomial support of is the set of monomials that appear as terms in a set of minimal generators of . Craig Huneke asked whether the size of a monomial support is a bound for the projective dimension of the ideal. We construct an example to show that, if the number of variables and the degrees of the generators are unspecified, the projective dimension of grows at least exponentially with the size of a monomial support. The ideal we construct is generated by monomials and binomials.

     

Analysis of the Cahn–Hilliard Equation with a Chemical Potential Dependent Mobility

The aim of this paper is to study the well-posedness and the existence of global attractors for a family of Cahn–Hilliard equations with a mobility depending on the chemical potential. Such models arise from generalizations of the (classical) Cahn–Hilliard equation due to Gurtin.     

Blaschke, Privaloff, Reade and Saks Theorems for Diffusion Equations on Lie Groups

We prove some asymptotic characterizations for the subsolutions to a class of diffusion equations on homogeneous Lie groups. These results are the diffusion counterpart of the classical Blaschke, Privaloff, Reade and Saks Theorems for harmonic functions.