Cyclic Carboxylic Anhydrides as New Reagents for Formation of Chromone Ring

The propensity of cyclic carboxylic anhydrides to undergo ring‐opening was exploited in a reaction with 2'‐hydroxy‐α‐heteroarylacetophenones leading to the formation of chromones. New simple method was developed for the synthesis of 2‐(ω‐carboxyalkyl)‐3‐heteroarylchromones without protecting either the phenolic or the carboxylic groups. Treatment with hydrazine led to the formation of 3(5)‐(ω‐carboxyalkyl)‐5(3)‐(2,4‐dihydroxyphenyl)‐4‐heteroarylpyrazoles.     

A biocatalytic cascade with several output signals—towards biosensors with different levels of confidence

The biocatalytic cascade based on enzyme-catalyzed reactions activated by several biomolecular input signals and producing output signal after each reaction step was developed as an example of a logically reversible information processing system. The model system was designed to mimic the operation of concatenated AND logic gates with optically readable output signals generated at each step of the logic operation. Implications include concurrent bioanalyses and data interpretation for medical diagnostics.

Effect of the synthesis conditions on the formation of MgSrP2O7 and its characterisation for pigmentary application

In present research, we examined MgSrP₂O₇ as a new pigment with focus on its application as a corrosion inhibitor. The influence of the synthesis’ conditions on the product properties was examined. Samples were obtained by solid-state reaction and various homogenisation methods of initial components were employed (hand-milling, wet (ethanol/acetone) ball-milling and coprecipitation). Thermal behaviour of the reaction mixtures or dried coprecipitate was investigated using differential thermal and thermo-gravimetric analyses. Obtained samples were characterised with X-ray diffraction analysis, scanning electron microscopy and IR spectroscopy. Focusing on pigmentary application, specific properties of the samples were evaluated, such as thermal stability, mean particle size values and colour parameters, and also preliminary anticorrosion tests have been performed. Based on obtained results, MgSrP₂O₇ could be considered as a perspective corrosion inhibitor and homogenisation via coprecipitation can be rated as the best method of preparation of this composition, which provides the best thermal stability, the lowest particle size, the best homogeneity and the most promising corrosion inhibition characteristics (pH and ρ of the pigment aqua suspension) for the final product.     

Mimicking Photosystem I with a Transmembrane Light Harvester and Energy Transfer-Induced Photoreduction in Phospholipid Bilayers

Photosystem I (PS I) is a transmembrane protein that assembles perpendicular to the membrane, and performs light harvesting, energy transfer, and electron transfer to a final, water-soluble electron acceptor. We present here a supramolecular model of it formed by a bicationic oligofluorene 1²⁺ bound to the bisanionic photoredox catalyst eosin Y (EY²⁻) in phospholipid bilayers. According to confocal microscopy, molecular modeling, and time dependent density functional theory calculations, 1²⁺ prefers to align perpendicularly to the lipid bilayer. In presence of EY²⁻, a strong complex is formed (K_a=2.1±0.1×10⁶ m ⁻¹), which upon excitation of 1²⁺ leads to efficient energy transfer to EY²⁻. Follow-up electron transfer from the excited state of EY²⁻ to the water-soluble electron donor EDTA was shown via UV–Vis absorption spectroscopy. Overall, controlled self-assembly and photochemistry within the membrane provides an unprecedented yet simple synthetic functional mimic of PS I.     

Electromagnetic flow control in liquid metals using Lorentz force techniques

Flow measurement and flow control in opaque and aggressive liquids such as metal melts are challenging tasks in industrial fluid mechanics. Optical measurement techniques as well as submerging probes or control units cannot be applied in case of highly severe environment; hence, contactless electromagnetic methods are of interest for practical flow control because of relatively high electrical conductivity of investigated materials. In this paper we present working principle and experimental results of two such contactless techniques. First, time-of-flight Lorentz force velocimetry (LFV), which allows to determine the flow rate of liquid metal without information about any fluid properties or magnetic field magnitude by cross-correlation of two Lorentz force signals. Secondly, Lorentz torque velocimetry (LTV) - a technique, which uses an electromagnetic pump with a torque sensor connected to the pump's shaft. In the methods so-called Lorentz force [1] is measured, which has electromagnetic nature and is proportional to velocity and flow rate of conductive liquid. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Phase formation in molten system (Na/K)2O‐TiO2‐P2O5. Crystal structures of NASICON and langbeinite‐related phosphates (K/Na)1+xTi2(PO4)3 (x = 0 and 0.357)

Crystallization of high temperature self‐flux of system Na₂O‐K₂O‐TiO₂‐P₂O₅ was investigated at different molar ratios (Na+K)/P = 0.9; 1.0 or 1.2 and Na/K = 1.0 or 2.0 over the temperature range 1000–650°C. The conditions of formation of complex phosphates K_0.10Na_0.90Ti₂(PO₄)₃ (NASICON‐related) and K_0.877Na_0.48Ti^ІІІ_0.357Ti^ІV_1.643(PO₄)₃ (langbeinite‐related) have been established. The new obtained compounds were investigated using FTIR‐spectroscopy, powder and single crystal X‐ray diffraction and optical microscopy methods. The influence of alkaline metal nature on the structure formation of complex phosphates in the high temperature self‐fluxes is discussed.     

Comparative Evaluation of the Essential Oil of the New Ukrainian Lavandula angustifolia and Lavandula x intermedia Cultivars Grown on the Same Plots

New cultivars of lavender adapted to arid steppe conditions were developed by the Institute of Rice of Ukrainian National Academy of Agrarian Sciences (NAAS). This work is a part of the characterization process of the new cultivars. The chemical composition of the essential oil of the seven new Lavandula angustifolia and eight new Lavandula x intermedia cultivars was investigated and compared. In total, 71 different compounds were identified. Linalool and linalool acetate were the main components in both species in ranges of 26.14–57.07% and 9.08–24.45%, respectively. They were followed by terpinen-4-ol (2.16–22.44%), lavandulyl acetate (2.12–10.23%), and lavandulol (1.30–3.14) in the case of L. angustifolia and camphor (10.11–12.55%), borneol (5.49–8.71%), and eucalyptol (0.47–7.41%) in the case of L. x intermedia. The oils had a valuable terpene profile—a high linalool content and the substantial presence of lavandulol and its ester. Nevertheless, they did not comply with the industry standards, mostly due to high levels of terpinene-4-ol. Evidently, a high content of terpinen-4-ol is a characteristic feature of L. angustifolia oils bred in Ukraine. Additionally, the LA3 cultivar yielded an oil with some of the highest linalool contents reported in the literature. Statistical analysis and literature data allowed for the comparative analysis of the gathered data. MANOVA, PCA, and HCA marked caryophyllene oxide as another potential differentiating compound between studied species.     

On equivalent strictly G-convex renormings of Banach spaces

We study strictly G-convex renormings and extensions of strictly G-convex norms on Banach spaces. We prove that ℓ_ω(Γ) space cannot be strictly G-convex renormed given Γ is uncountable and G is bounded and separable.     

Nerve Targeting via Myelin Protein Zero and the Impact of Dimerization on Binding Affinity

Background: Surgically induced nerve damage is a common but debilitating side effect. By developing tracers that specifically target the most abundant protein in peripheral myelin, namely myelin protein zero (P0), we intend to support fluorescence-guided nerve-sparing surgery. To that end, we aimed to develop a dimeric tracer that shows a superior affinity for P0. Methods: Following truncation of homotypic P0 protein-based peptide sequences and fluorescence labeling, the lead compound Cy5-P0_101–125 was selected. Using a bifunctional fluorescent dye, the dimeric Cy5-(P0_101–125)₂ was created. Assessment of the performance of the mono- and bi-labeled compounds was based on (photo)physical evaluation. This was followed by in vitro assessment in P0 expressing Schwannoma cell cultures by means of fluorescence confocal imaging (specificity, location of binding) and flow cytometry (binding affinity; K_D). Results: Dimerization resulted in a 1.5-fold increase in affinity compared to the mono-labeled counterpart (70.3 +/− 10.0 nM vs. 104.9 +/− 16.7 nM; p = 0.003) which resulted in a 4-fold increase in staining efficiency in P0 expressing Schwannoma cells. Presence of two targeting vectors also improves a pharmacokinetics of labeled compounds by lowering serum binding and optical stability by preventing dye stacking. Conclusions: Dimerization of the nerve-targeting peptide P0_101–125 proves a valid strategy to improve P0 targeting.     

Chemical Variability and Pharmacological Potential of Propolis as a Source for the Development of New Pharmaceutical Products

This review aims to analyze propolis as a potential raw material for the development and manufacture of new health-promoting products. Many scientific publications were retrieved from the Scopus, PubMed, and Google Scholar databases via searching the word "propolis". The different extraction procedures, key biologically active compounds, biological properties, and therapeutic potential of propolis were analyzed. It was concluded that propolis possesses a variety of biological properties because of a very complex chemical composition that mainly depends on the plant species visited by bees and species of bees. Numerous studies found versatile pharmacological activities of propolis: antimicrobial, antifungal, antiviral, antioxidant, anticancer, anti-inflammatory, immunomodulatory, etc. In this review, the composition and biological activities of propolis are presented from a point of view of the origin and standardization of propolis for the purpose of the development of new pharmaceutical products on its base. It was revealed that some types of propolis, especially European propolis, contain flavonoids and phenolic acids, which could be markers for the standardization and quality evaluation of propolis and its preparations. One more focus of this paper was the overview of microorganisms’ sensitivity to propolis for further development of antimicrobial and antioxidant products for the treatment of various infectious diseases with an emphasis on the illnesses of the oral cavity. It was established that the antimicrobial activity of different types of propolis is quite significant, especially to Gram-negative bacteria and lipophilic viruses. The present study could be also of interest to the pharmaceutical industry as a review for the appropriate design of standardized propolis preparations such as mouthwashes, toothpastes, oral drops, sprays, creams, ointments, suppositories, tablets, and capsules, etc. Moreover, propolis could be regarded as a source for the isolation of biologically active substances. Furthermore, this review can facilitate partially overcoming the problem of the standardization of propolis preparations, which is a principal obstacle to the broader use of propolis in the pharmaceutical industry. Finally, this study could be of interest in the area of the food industry for the development of nutritionally well-balanced products. The results of this review indicate that propolis deserves to be better studied for its promising therapeutic effects from the point of view of the connection of its chemical composition with the locality of its collection, vegetation, appropriate extraction methods, and standardization.