Opuntia ficus-indica (L.) Miller as a source of bioactivity compounds for health and nutrition

Plants with beneficial properties are known in traditional medicine. Nowadays, in spite of widespread availability of synthetic compounds, the search goes towards natural compounds to lower cost and few side effects. The increasing interest in preventive medicine encourages use of nutraceuticals, bioactive compounds of vegetable origin with important nutritional values. Among the medicinal plants, Opuntia ficus-indica (L.) Miller (Family Cactaceae, subfamily Opuntiodeae, Genus Opuntia, subgenus Platyopuntia, species Opuntia ficus-indica (L.) Miller) is widely known for its beneficial properties. The aim of the present review is to stress the major classes of Opuntia components and their medical interest through emphasis on some of their biological effects, particularly those having the most promising expected health benefits and therapeutic impacts on fish and mammals.     

Morphological Stability of the Solid–Liquid Interface during Melt Crystallization of Ca1–xSrxF2 Solid Solution

Crystallography Reports - Proceeding from the phase diagram of the CaF2–SrF2 system, the stability of crystal–melt interface of solid solution against constitutional supercooling has...     

Fluid‐structure coupling of linear elastic model with compressible flow models

Cavitation erosion is caused in solids exposed to strong pressure waves developing in an adjacent fluid field. The knowledge of the transient distribution of stresses in the solid is important to understand the cause of damaging by comparisons with breaking points of the material. The modeling of this problem requires the coupling of the models for the fluid and the solid. For this purpose, we use a strategy based on the solution of coupled Riemann problems that has been originally developed for the coupling of 2 fluids. This concept is exemplified for the coupling of a linear elastic structure with an ideal gas. The coupling procedure relies on the solution of a nonlinear equation. Existence and uniqueness of the solution is proven. The coupling conditions are validated by means of quasi‐1D problems for which an explicit solution can be determined. For a more realistic scenario, a 2D application is considered where in a compressible single fluid, a hot gas bubble at low pressure collapses in a cold gas at high pressure near an adjacent structure.     

Influence of nonlinear subunits on the resonance frequency band gaps of acoustic metamaterial

Nonlinear Dynamics - Recently, a significant attention has been directed toward so called ‘acoustic metamaterials’ which have large similarity with already-known ‘electromagnetic...     

A Dual Threat: Redox-Activity and Electronic Structures of Well-Defined Donor–Acceptor Fulleretic Covalent-Organic Materials

The effect of donor (D)–acceptor (A) alignment on the materials electronic structure was probed for the first time using novel purely organic porous crystalline materials with covalently bound two- and three-dimensional acceptors. The first studies towards estimation of charge transfer rates as a function of acceptor stacking are in line with the experimentally observed drastic, eight-fold conductivity enhancement. The first evaluation of redox behavior of buckyball- or tetracyanoquinodimethane-integrated crystalline was conducted. In parallel with tailoring the D-A alignment responsible for “static” changes in materials properties, an external stimulus was applied for “dynamic” control of the electronic profiles. Overall, the presented D–A strategic design, with stimuli-controlled electronic behavior, redox activity, and modularity could be used as a blueprint for the development of electroactive and conductive multidimensional and multifunctional crystalline porous materials.     

How to Increase Water Resistance of Adhesive Wood Compounds Formed by Adhesives Based on Polyvinyl-Acetate Dispersion

The influence of glyoxal on the water resistance of pine–pine and beech–beech wood compounds formed by adhesives on the basis of polyvinyl acetate dispersion is studied. A noticeable increase in water resistance is observed for pine–pine compounds if the adhesive composite contains not only glyoxal, but also aluminum chloride and “chymol” additives. However, in the case of beech–beech compounds, the effect of this composition becomes less pronounced.     

Adsorption of heavy metals by layered double hydroxides grown in situ on Al foam

We investigated the adsorption of heavy metal ions on a nanostructured coating of zinc-aluminum layered double hydroxides (Zn-Al LDHs) grown on aluminum foam by one-step hydrothermal process. This approach aimed to increase the interactive surface and provide a more practical medium for removal of toxic heavy metals from aqueous media. The foam coated with LDH was characterized by using scanning electron microscopy and X-ray diffraction. After immersion in a copper-rich water solution, X-ray photoelectron spectroscopy demonstrated the occurrence of adsorbed copper on the LDH-coated foam with two oxidation states: particles of metallic copper Cu⁰ with oxidized surface Cu⁺¹. X-ray diffraction showed the presence of Cu⁺² in the LDH structure.     

Exciton Interactions,Excimer Formation,and [2π+2π] Photodimerization in Nonconjugated Curcuminoid-BF2 Dimers

We describe the synthesis of a series of covalently linked dimers of quadrupolar curcuminoid-BF₂ dyes and the detailed investigation of their solvent-dependent spectroscopic and photophysical properties. In solvents of low polarity, intramolecular folding induces the formation of aggregated chromophores, the UV/Vis absorption spectra of which display the optical signature characteristic of weakly-coupled H-aggregates. The extent of folding and, in turn, of ground-state aggregation is strongly dependent on the nature of the flexible linker. Steady-state and time-resolved fluorescence emission spectroscopies show that the Frenkel exciton relaxes into a fluorescent symmetrical excimer state with a long lifetime. Furthermore, our in-depth studies show that a weakly emitting excimer lies on the pathway toward a photocyclomer. Two-dimensional ¹H NMR spectroscopy and density functional theory (DFT) allowed the structure of the photoproduct to be established. To our knowledge, this represents the first example of a [2π+2π] photodimerization of the curcuminoid chromophore.