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The incommensurately modulated antiferroelectric phase of sodium nitrite, NaNO2, transforms at TN = 437.7 K to the short-range modulated paraelectric phase. The apparently discontinuous phase transition is accompanied by characteristic changes in the diffraction pattern. Contrary to the well known modulated structures with sharp satellite reflections, the diffraction pattern of a short-range modulated structure contains diffuse satellite reflections. The short-range modulated crystal structure of the paraelectric phase of sodium nitrite has been analysed by the Reverse Monte Carlo (RMC) simulation of X-ray diffuse scattering. The crystal structure of sodium nitrite may be regarded as consisting of [Na+NO ]∞ rows running along the polar b axis. One can expect long fragments of rows with uniform polarity The assumption that single [Na+NO ]∞ rows are polar with uniform polarity proved to be a convenient approximation which is in good agreement with the observed diffraction pattern. The distribution of (+)- and (−)-[Na+NO ]∞ polar rows crossing the (010) plane of short-range modulated NaNO2 revealed by RMC shows nanodomains consisting of distorted fragments of a sinusoidally modulated crystal structure. The size of the nanodomains and the degree of order in paraelectric NaNO2 decreases with temperature. [ABSTRACT FROM AUTHOR]

Investigations are presented for the preparation of a model hemostatic dressing that would exhibit an adequate hemostatic capacity in injuries and surgical wounds, an antibacterial activity to prevent primary and secondary infections, and offer safety in use. The Hemoguard dressing has been designed as a powder prepared from the complex chitosan/alginate Na/Ca in the form of micro- and nano-fibrids. Useful antibacterial and hemostatic properties of Hemoguard, which would qualify the material as first aid dressing and a temporary protection of injury wounds in field conditions, were assessed. Biocompatibility of the dressing was confirmed by biological in vitro examinations.

Aim of the presented research was the improvement of fibrous cellulosic products for uses in hygiene and medical sectors. Nano-particles of bioactive polysaccharides were imparted to cellulosic fibrous products to modify their properties: physical–chemical like absorption, biological like antibacterial and antifungal activity, and mechanical. Fibrous materials like dressing gauze, wood-wool, and hygiene tissues were modified by the addition of chitosan and chitosan-alginate nano-particles. Padding and freeze-drying was applied in the coating of the fibrous materials with the nano-sized polymers.

The paper presents results of an analysis conducted in order to determine a cause of an emergency state of a timber roof rafter framing of a central nave ceiling in a church. The article showed an assessment of the current technical conditions, a description of the diagnostic tests performed and the results of the static strength analysis. Based on that information, the causes of this emergency state are described as the consequence of contractor’s errors during the execution and significant derogations from the construction design. Moreover, an implementation of a repair programme in order to restore the full value in use of the building is recommended.

The incommensurately modulated antiferroelectric phase of sodium nitrite, NaNO2, transforms at TN = 437.7 K to the short-range modulated paraelectric phase. The apparently discontinuous phase transition is accompanied by characteristic changes in the diffraction pattern. Contrary to the well known modulated structures with sharp satellite reflections, the diffraction pattern of a short-range modulated structure contains diffuse satellite reflections. The short-range modulated crystal structure of the paraelectric phase of sodium nitrite has been analysed by the Reverse Monte Carlo (RMC) simulation of X-ray diffuse scattering. The crystal structure of sodium nitrite may be regarded as consisting of [Na+NO ]∞ rows running along the polar b axis. One can expect long fragments of rows with uniform polarity The assumption that single [Na+NO ]∞ rows are polar with uniform polarity proved to be a convenient approximation which is in good agreement with the observed diffraction pattern. The distribution of (+)- and (−)-[Na+NO ]∞ polar rows crossing the (010) plane of short-range modulated NaNO2 revealed by RMC shows nanodomains consisting of distorted fragments of a sinusoidally modulated crystal structure. The size of the nanodomains and the degree of order in paraelectric NaNO2 decreases with temperature. [ABSTRACT FROM AUTHOR]

Raman spectroscopy was used to study erythrocytes collected from patients diagnosed with malaria at the University Hospital in Kraków and from healthy volunteers. A laser line with a wavelength of 442 nm was used to induce the Raman resonance of haem, while a laser with a wavelength of 785 nm was used for the normal Raman effect. The results were analysed using Principal Component Analysis. For the 442 nm laser line, analysis of the entire spectral range (3200 cm -1 to 300 cm -1 ) showed satisfactory separation of Raman spectra for healthy cells from infected cells, which was significantly improved in the 1500 cm -1 -1200 cm -1 spectral range. For the 785 nm laser line, some separation was observed in each range studied, but the best results were achieved over the full spectral range. Plasmodium-derived nucleic acids and phosphodiester vibrations were observed at excitation lines of 442 nm and 785 nm, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cinchonine is a quinoline alkaloid known for its antimalarial properties. Due to the advantages of using compounds of metal ions with alkaloids, a copper(II) compound with cinchonine was synthesized, and, for comparative purposes, a cadmium(II) compound with cinchonine. During the synthesis, the emerging interactions between the metal ion and cinchonine were studied. After crystallization, it was examined how the obtained compounds would interact with the model blood component, hematoporphyrin IX. Ultraviolet-visible (UV-Vis) spectroscopy, Raman spectroscopy, and attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) were used in the study. In the case of monitoring the synthesis, the best method turned out to be UV-Vis spectroscopy, combined with the possibility of two-dimensional correlation spectroscopy (2D-COS), which enabled the identification of peaks characteristic of the interactions of the cinchonine quinoline ring with metal ions. In turn, the obtained Raman spectra showed shifts of individual bands and changes in their intensity, and 2D-COS showed the sequence of formation of individual interactions, which confirmed the formation of cinchonine compounds with metals. ATR FT-IR also allowed us to compare the spectra of the substrates used in the synthesis with the crystallized compounds and thus confirm the formation of the expected compounds. Bands characteristic of π-π-stacking interactions between the quinoline ring and the tetrapyrrole ring of hematoporphyrin IX were also observed. Observed interaction with a model blood component may be important when designing drugs for antimalarial therapy., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.