Dynamical mean-field theory from a quantum chemical perspective

We investigate the dynamical mean-field theory (DMFT) from a quantum chemical perspective. Dynamical mean-field theory offers a formalism to extend quantum chemical methods for finite systems to infinite periodic problems within a local correlation approximation. In addition, quantum chemical techniques can be used to construct new ab initio Hamiltonians and impurity solvers for DMFT. Here, we explore some ways in which these things may be achieved. First, we present an informal overview of dynamical mean-field theory to connect to quantum chemical language. Next, we describe an implementation of dynamical mean-field theory where we start from an ab initio Hartree-Fock Hamiltonian that avoids double counting issues present in many applications of DMFT. We then explore the use of the configuration interaction hierarchy in DMFT as an approximate solver for the impurity problem. We also investigate some numerical issues of convergence within DMFT. Our studies are carried out in the context of the cubic hydrogen model, a simple but challenging test for correlation methods. Finally, we finish with some conclusions for future directions.     

The Hydrogen–Deuterium Exchange at α-Carbon Atom in <Emphasis Type="BoldItalic">N,N,N</Emphasis>-Trialkylglycine Residue: ESI-MS Studies

Derivatization of peptides as quaternary ammonium salts (QAS) is a known method for sensitive detection by electrospray ionization tandem mass spectrometry. Hydrogens at α-carbon atom in N,N,N-trialkylglycine residue can be easily exchanged by deuterons. The exchange reaction is base-catalyzed and is dramatically slow at lower pH. Introduced deuterons are stable in acidic aqueous solution and are not back-exchanged during LC-MS analysis. Increased ionization efficiency, provided by the fixed positive charge on QAS group, as well as the deuterium labeling, enables the analysis of trace amounts of peptides.     

The Spectrofluorometric Monitoring of Water Purification by Natural Alternatives

Aim: Determination of efficiency of zeolite and hydrolytic enzymes isolated from earthworms in water purification.

Methods: The autofluorescence of water was investigated by fluorescence excitation–emission matrix. The purification of water was carried out with natural zeolite and hydrolytic enzymes isolated from earthworms. These methods were applied to samples that contain ciliates that were detected with atomic force spectroscopy.

Results: The zeolite removed ammonia and partly eliminated some organic compounds. The hydrolytic enzymes were efficient in biodegrading organic compounds present in water.

Conclusion: Zeolite and enzymes are applicable in water purification.     

Analysis of Antioxidant Capacity and Antimicrobial Properties of Selected Polish Grape Vinegars Obtained by Spontaneous Fermentation

Nowadays, products of natural origin with health-promoting properties are increasingly more common. Research shows that fruit vinegars can be a source of compounds with antioxidant activity. Research on the total antioxidant capacity, total phenolic content, and antimicrobial properties against Staphylococcus aureus, Escherichia coli, and Candida albicans of grape vinegars were conducted. Moreover, gas chromatography was used to measure acetic acid content in the vinegars. The research material consisted of vinegars produced from five different grape varieties. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The highest antimicrobial activity against all micro-organisms was observed in vinegar produced from Solaris grapes with added sugar. The highest polyphenol content was observed in vinegar produced from the Prior grape variety with added sugar and the highest total antioxidant capacity is the Johanniter grape variety with added sugar. The vinegars examined in this study differed, depending on grape variety, in terms of antimicrobial properties, antioxidant capacity, total phenolic content, as well as acetic acid content. Sugar addition caused significant differences in the antioxidant capacity of vinegar samples.     

MA-XRF study of 15th–17th century icons from the collection of the National Museum in Krakow,Poland

In 2015, the National Museum in Krakow, Poland, started a grant from the National Programme for the Development of Humanities, its goal to investigate an important collection of old Orthodox painting, including more than 50 15th to 17th century icons originating from the territory of the historical Orthodox Diocese of Przemyśl within the borders of the Polish Kingdom. The aim of researching the iconography, provenance, and technology of the artworks was to describe their specific features and destination, in detail, and to characterise their artistic milieu. Many different techniques were used during research, such as X-ray fluorescence (XRF), X-ray diffraction, reflectography, radiography, ultraviolet–visible imaging, Fourier-transform infrared spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy of prepared paint layer cross sections, and dendro-chronological analysis. This paper focuses on highlighting the advantages and disadvantages of the spatially resolved macro-XRF scanning (MA-XRF) technique. Most interesting results concluded from elemental distribution maps obtained through the use of Bruker, M6 Jetstream MA-XRF scanner include the following: characterisation of the type of gold and silver foil used in the icons; determination of main pigments, including the use of lead tin yellow unusual in iconography; and the noting of an interesting distribution of blue pigments as well as the presence of orpiment. Surprisingly, a considerable amount of zinc with azurite addition was observed in brown layers. The results obtained primarily highlight all the typical features of local Carpathian icon craft.     

Effect of Three Commercial Formulations Containing Effective Microorganisms (EM) on Diflufenican and Flurochloridone Degradation in Soil

The aim of this study was to determine the influence of effective microorganisms (EM) present in biological formulations improving soil quality on degradation of two herbicides, diflufenican and flurochloridone. Three commercially available formulations containing EM were used: a formulation containing Bifidobacterium, Lactobacillus, Lactococcus, Streptococcus, Bacillus, and Rhodopseudomonas bacteria and the yeast Saccharomyces cerevisiae; a formulation containing Streptomyces, Pseudomonas, Bacillus, Rhodococcus, Cellulomonas, Arthrobacter, Paenibacillusa, and Pseudonocardia bacteria; and a formulation containing eight strains of Bacillus bacteria, B. megaterium, B. amyloliquefaciens, B. pumilus, B. licheniformis, B. coagulans, B. laterosporus, B. mucilaginosus, and B. polymyxa. It was demonstrated that those formulations influenced degradation of herbicides. All studied formulations containing EM reduced the diflufenican degradation level, from 35.5% to 38%, due to an increased acidity of the soil environment and increased durability of that substance at lower pH levels. In the case of flurochloridone, all studied EM formulations increased degradation of that active substance by 19.3% to 31.2% at the most. For control samples, equations describing kinetics of diflufenican and flurochloridone elimination were plotted, and a time of the half-life of these substances in laboratory conditions was calculated, amounting to 25.7 for diflufenican and 22.4 for flurochloridone.     

Application of Levan-Rich Digestate Extract in the Production of Safe-to-Use and Functional Natural Body Wash Cosmetics

The study focused on the evaluation of the possibility of using a levan-rich digestate extract in the production of safe and functional body wash cosmetics. Model shower gels were designed and formulated on the basis of raw materials of natural origin. Prepared prototypes contained various extract concentrations (16.7; 33; 50%). A gel without extract was used as a reference. The samples were evaluated for their safety in use and functionality. The results showed that the use of high-concentration levan-rich digestate extract in a shower gel resulted in a significant reduction in the negative impact on the skin. For example, the zein value decreased by over 50% in relation to the preparation without the extract. An over 40% reduction in the emulsifying capacity of hydrophobic substances was also demonstrated, which reduces skin dryness after the washing process. However, the presence of the extract did not significantly affect the parameters related to functionality. Overall, it was indicated that levan-rich digestate extract can be successfully used as a valuable ingredient in natural cleansing cosmetics.     

Antiproliferative Properties of Triterpenoids by ECIS Method—A New Promising Approach in Anticancer Studies?

Electric cell–substrate impedance sensing is an advanced in vitro impedance measuring system which uses alternating current to determine behavior of cells in physiological conditions. In this study, we used the abovementioned method for checking the anticancer activities of betulin and betulinic acid, which are some of the most commonly found triterpenes in nature. In our experiment, the threshold concentrations of betulin required to elicit antiproliferative effects, verified by MTT and LDH release methods, were 7.8 µM for breast cancer (T47D), 9.5 µM for lung carcinoma (A549), and 21.3 µM for normal epithelial cells (Vero). The ECIS results revealed the great potential of betulin and betulinic acid’s antitumor properties and their maintenance of cytotoxic substances to the breast cancer T47D line. Moreover, both substances showed a negligible toxic effect on healthy epithelial cells (Vero). Our investigation showed that the ECIS method is a proper alternative to the currently used assay for testing in vitro anticancer activity of compounds, and that it should thus be introduced in cellular routine research. It is also a valuable tool for live-monitoring changes in the morphology and physiology of cells, which translates into the accurate development of anticancer therapies.     

Are Organic Certified Carrots Richer in Health-Promoting Phenolics and Carotenoids than the Conventionally Grown Ones?

The aim of the present study was to determine the concentrations of polyphenols and carotenoids by means of HPLC/UV-Vis in certified organic and non-organic carrots (Daucus carota L.) of two cultivars (Flacoro and Nantejska). The analyzed carrot root samples contained, on average, 4.29 ± 0.83 mg/100g f.w. of carotenoids (mainly β-carotene) and 9.09 ± 2.97 mg/100g f.w. of polyphenols, including 4.44 ± 1.42 mg/100g f.w. of phenolic acids and 4.65 ± 1.96 mg/100g f.w. of flavonoids. Significant effects of the production system on the carotenoids (total) and β-carotene concentration were found, with higher concentrations of these compounds generally identified in conventionally cultivated roots (4.67 ± 0.88 mg/100g f.w.) vs. organically grown ones (4.08 ± 0.74 mg/100g f.w.). There was a noticeable inter-sample (inter-farm) variation in the concentration of polyphenols in carrot roots. Despite a general trend towards higher concentrations of these compounds in the organic carrots (9.33 ± 3.17 mg/100g f.w.) vs. conventional carrots (8.64 ± 2.58 mg/100g f.w.), and in those of Nantejska (9.60 ± 2.87 mg/100g f.w.) vs. Flacoro (8.46 ± 3.02 mg/100g f.w.) cultivar, no consistent, statistically significant impact of the production system and/or cultivar on the level of these bioactive compounds was identified. More efforts should be encouraged to ensure that organic crops reaching the market consistently contain the expected high levels of health-promoting bioactive compounds, which could be brought through their shelf-life and all processing steps, in order to meet consumers’ expectations and provide the expected health benefits.