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.     

The Recognition of and Reactions to Nucleic Acid Nanoparticles by Human Immune Cells

The relatively straightforward methods of designing and assembling various functional nucleic acids into nanoparticles offer advantages for applications in diverse diagnostic and therapeutic approaches. However, due to the novelty of this approach, nucleic acid nanoparticles (NANPs) are not yet used in the clinic. The immune recognition of NANPs is among the areas of preclinical investigation aimed at enabling the translation of these novel materials into clinical settings. NANPs’ interactions with the complement system, coagulation systems, and immune cells are essential components of their preclinical safety portfolio. It has been established that NANPs’ physicochemical properties—composition, shape, and size—determine their interactions with immune cells (primarily blood plasmacytoid dendritic cells and monocytes), enable recognition by pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) and RIG-I-like receptors (RLRs), and mediate the subsequent cytokine response. However, unlike traditional therapeutic nucleic acids (e.g., CpG oligonucleotides), NANPs do not trigger a cytokine response unless they are delivered into the cells using a carrier. Recently, it was discovered that the type of carrier provides an additional tool for regulating both the spectrum and the magnitude of the cytokine response to NANPs. Herein, we review the current knowledge of NANPs’ interactions with various components of the immune system to emphasize the unique properties of these nanomaterials and highlight opportunities for their use in vaccines and immunotherapy.     

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.     

On the spin and symmetry adaptation of the density matrix renormalization group method

We present a spin-adapted density matrix renormalization group (DMRG) algorithm designed to target spin and spatial symmetry states that can be difficult to obtain while using a non-spin-adapted algorithm. The algorithmic modifications that have to be introduced into the usual density matrix renormalization group scheme in order to spin adapt it are discussed, and it is demonstrated that the introduced modifications do not change the overall scaling of the method. The new approach is tested on HNCO, a model system, that has a singlet-triplet curve crossing between states of the same symmetry. The advantages of the spin-adapted DMRG scheme are discussed, and it is concluded that the spin-adapted DMRG method converges better in almost all cases and gives more parallel curves to the full configuration interaction result than the non-spin-adapted method. It is shown that the spin-adapted DMRG energies can be lower than the ones obtained from the non-spin-adapted scheme. Such a counterintuitive result is explained by noting that the spin-adapted method is not a special case of the non-spin-adapted one; consequently, the spin-adapted result is not an upper bound for the non-spin-adapted energy.     

New electrode material GCE/AgNPs-D3 as an electrochemical sensor used for the detection of thallium ions

Optimal working parameters for the innovative electrode GCE/AgNPs-D3 were determined and the selectivity was assessed. The stripping anodic peak current of thallium characterized in linearity over range from 4.9 ⋅ 10⁻⁸ to 4.9 ⋅ 10⁻⁷ mol ⋅ dm⁻³, with LOD = 7.16 ppb (3.5 ⋅ 10⁻⁸ mol ⋅ dm⁻³). Furthermore, the new electrode showed more than sevenfold improvement in the thallium current signal compared to the unmodified electrode GCE. High selectivity was achieved using EDTA disodium salt as a complexing agent for other metals.     

Low-dimensional compounds containing bioactive ligands. XXII. First crystal structure,cytotoxic activity and DNA and HSA binding of a zirconium(IV) complex with 8-hydroxyquinoline-2-carboxylic acid

A new zirconium(IV) complex, diaquabis(8-hydroxyquinoline-2-carboxylato-κ³N,O²,O⁸)zirconium(IV) dimethylformamide disolvate, [Zr(C₁₀H₅NO₃)₂(H₂O)₂]·2C₃H₇NO or [Zr(QCa)₂(H₂O)₂]·2DMF ( 1 ) (HQCaH is 8-hydroxyquinoline-2-carboxylic acid and DMF is dimethylformamide), was prepared and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray structure analysis. Complex 1 is a mononuclear complex in which the Zr^IV atoms sit on the twofold axis and they are octacoordinated by two N and six O atoms of two tridentate anionic QCa²⁻ ligands, and two aqua ligands. Outside the coordination sphere are two DMF molecules bound to the complex unit by hydrogen bonds. The structure and stability of complex 1 in dimethyl sulfoxide were verified by NMR spectroscopy. The cytotoxic properties of 1 and HQCaH were studied in vitro against eight cancer cell lines, and their selectivity was tested on the BJ-5ta noncancerous cell line. Both the complex and HQCaH exhibited low activity, with IC₅₀ > 200 µM. DNA and human serum albumin (HSA) binding studies showed that 1 binds to calf thymus (CT) DNA via intercalation and is able to bind to the tryptophan binding site of HSA (Trp-214).     

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.     

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.     

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.