Combined effect of Fe2+ ions and the meta-isomer of dihydric phenol on duckweed

The toxic effects of Fe2+ ions and resorcinol on Lemna minor in their joint presence in the aquatic environment were studied. The test response in the bioassay of solutions of Fe2+, resorcinol, and their mixtures was a violation of the permeability of duckweed membranes. This parameter was estimated from the change in the electrical conductivity of the aquatic medium in which the plant was placed, exposed to the toxicant in the acute experiment (30 min). It was found that the addition of both an equinormal concentration of Fe(II) (0.1n) and a five-fold deficiency (0.02n) to a 0.1n solution of resorcinol reduced the toxicity of resorcinol. Most likely, the effect obtained can be achieved by the formation of a new, less toxic compound (probably of a complex nature). The test used in the work, based on the assessment of the permeability of cell membranes under the action of toxicants, once again proved to be a promising tool for analyzing the combined toxicity of phenolic compounds and metal ions in relation to plant organisms

Combined effect of Fe

The toxic effects of Fe2+ ions and resorcinol on Lemna minor in their joint presence in the aquatic environment were studied. The test response in the bioassay of solutions of Fe2+, resorcinol, and their mixtures was a violation of the permeability of duckweed membranes. This parameter was estimated from the change in the electrical conductivity of the aquatic medium in which the plant was placed, exposed to the toxicant in the acute experiment (30 min). It was found that the addition of both an equinormal concentration of Fe(II) (0.1n) and a five-fold deficiency (0.02n) to a 0.1n solution of resorcinol reduced the toxicity of resorcinol. Most likely, the effect obtained can be achieved by the formation of a new, less toxic compound (probably of a complex nature). The test used in the work, based on the assessment of the permeability of cell membranes under the action of toxicants, once again proved to be a promising tool for analyzing the combined toxicity of phenolic compounds and metal ions in relation to plant organisms

Preoperative AI-Driven Fluorescence Diagnosis of Non-Melanoma Skin Cancer

The diagnosis and treatment of non-melanoma skin cancer remain urgent problems. Histological examination of biopsy material—the gold standard of diagnosis—is an invasive procedure that requires a certain amount of time to perform. The ability to detect abnormal cells using fluorescence spectroscopy (FS) has been shown in many studies. This technique is rapidly expanding due to its safety, relative cost-effectiveness, and efficiency. However, skin lesion FS-based diagnosis is challenging due to a number of single overlapping spectra emitted by fluorescent molecules, making it difficult to distinguish changes in the overall spectrum and the molecular basis for it. We applied deep learning (DL) algorithms to quantitatively assess the ability of FS to differentiate between pathologies and normal skin. A total of 137 patients with various forms of primary and recurrent basal cell carcinoma (BCC) were observed by a multispectral laser-based device with a built-in neural network (NN) “DSL-1”. We measured the fluorescence spectra of suspected non-melanoma skin cancers and compared them with “normal” skin spectra. These spectra were input into DL algorithms to determine whether the skin is normal, pigmented normal, benign, or BCC. The preoperative differential AI-driven fluorescence diagnosis method correctly predicted the BCC lesions. We obtained an average sensitivity of 62% and average specificity of 83% in our experiments. Thus, the presented “DSL-1” diagnostic device can be a viable tool for the real-time diagnosis and guidance of non-melanoma skin cancer resection

Apicophilicity versus Hydrogen Bonding. Intramolecular Coordination and Hydrogen Bonds in <i>N</i>‑[(Hydroxydimethylsilyl)methyl]-<i><i>N,N</i></i>′‑propyleneurea and Its Hydrochloride. DFT and FT-IR Study and QTAIM and NBO Analysis

Conformers of <i>N</i>-[(hydroxydimethylsilyl)­methyl]-<i><i>N,N</i></i>′-propyleneurea (<b>1</b>) and their hydrochlorides (<b>2</b>) with HCl coordinated to different basic sites have been studied experimentally by FT-IR and theoretically using the density functional theory (DFT) method at the B3LYP/6-311+G­(d,p) and M06/6-311+G­(d,p) levels of theory. The structures of silanols <b>1</b> and <b>2</b> are determined by the balance of two competing effects: namely, intramolecular CO→Si coordination and intramolecular CO···H–O or intermolecular X···H–Cl hydrogen bonding. The preferred conformation of silanol <b>1</b> is that with an equatorial hydroxyl group, in apparent contradiction with the apicophilicity rule. In the crystal, silanol <b>1</b> exists as a conformer with a bifurcated bond composed of a weak CO→Si coordinated bond and a substantially more strong CO···H–O hydrogen bond. From the NBO analysis, the energies of the n_O → σ*_Si–X and n_O → σ*_H–O orbital interactions responsible for the formation of the coordination and hydrogen bonds, as well as the lengths of these bonds, change in opposite directions. In solution the equilibrium is shifted toward the conformer having only the hydrogen bond and no coordination bond. Its hydrochloride <b>2</b> exists in the crystal as a conformer with the axial OH group coordinated to HCl, whereas in solution it appears to be in equilibrium with a conformer having the equatorial OH group, in which a four-centered bifurcated bond is formed by two intramolecular components CO→Si and CO···HO and one intermolecular component CO···HCl. The QTAIM analysis showed the O→Si coordination bonds in the studied compounds to fall in the range from partially covalent and weak donor–acceptor to mainly electrostatic in nature and the hydrogen bonds to vary from weak to medium in energy

Apicophilicity versus Hydrogen Bonding. Intramolecular Coordination and Hydrogen Bonds in <i>N</i>‑[(Hydroxydimethylsilyl)methyl]-<i><i>N,N</i></i>′‑propyleneurea and Its Hydrochloride. DFT and FT-IR Study and QTAIM and NBO Analysis

Conformers of <i>N</i>-[(hydroxydimethylsilyl)­methyl]-<i><i>N,N</i></i>′-propyleneurea (<b>1</b>) and their hydrochlorides (<b>2</b>) with HCl coordinated to different basic sites have been studied experimentally by FT-IR and theoretically using the density functional theory (DFT) method at the B3LYP/6-311+G­(d,p) and M06/6-311+G­(d,p) levels of theory. The structures of silanols <b>1</b> and <b>2</b> are determined by the balance of two competing effects: namely, intramolecular CO→Si coordination and intramolecular CO···H–O or intermolecular X···H–Cl hydrogen bonding. The preferred conformation of silanol <b>1</b> is that with an equatorial hydroxyl group, in apparent contradiction with the apicophilicity rule. In the crystal, silanol <b>1</b> exists as a conformer with a bifurcated bond composed of a weak CO→Si coordinated bond and a substantially more strong CO···H–O hydrogen bond. From the NBO analysis, the energies of the n_O → σ*_Si–X and n_O → σ*_H–O orbital interactions responsible for the formation of the coordination and hydrogen bonds, as well as the lengths of these bonds, change in opposite directions. In solution the equilibrium is shifted toward the conformer having only the hydrogen bond and no coordination bond. Its hydrochloride <b>2</b> exists in the crystal as a conformer with the axial OH group coordinated to HCl, whereas in solution it appears to be in equilibrium with a conformer having the equatorial OH group, in which a four-centered bifurcated bond is formed by two intramolecular components CO→Si and CO···HO and one intermolecular component CO···HCl. The QTAIM analysis showed the O→Si coordination bonds in the studied compounds to fall in the range from partially covalent and weak donor–acceptor to mainly electrostatic in nature and the hydrogen bonds to vary from weak to medium in energy