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Photochemical transformations of small molecules, such as ortho -substituted benzaldehydes, in the absence of a photocatalyst are significantly underexplored and may reveal unexpected outcomes. In the present paper, we showed that 2-(2-formylphenoxy)acetic acid and its esters undergo photocyclization into chromanone and benzofuranone derivatives under 365 nm irradiation. The reaction occurs exclusively in dimethyl sulfoxide and can be used to efficiently obtain hydroxychromanones in good yields (27-91%). A detailed mechanistic study revealed the clue of the divergent phototransformation with various products.

2-Allyloxybenzaldehydes undergo [2 + 1] cycloadditions under 365 nm LED irradiation to form the corresponding chroman-fused cyclopropanols. The reaction proceeds easily without any catalysts or additives in dimethyl sulfoxide.

Nanoplastics have been widely studied as environmental pollutants, which can accumulate in the human body through the food chain or direct contact. Research has shown that nanoplastics can affect the immune system and mitochondrial function, but the underlying mechanisms are unclear. Lungs and macrophages have important immune and metabolic functions. This study explored the effects of 100 nm PS-NPs on innate immunity, mitochondrial function, and cellular metabolism-related pathways in lung (BEAS-2B) cells and macrophages (RAW264.7). The results had shown that PS-NPs exposure caused a decrease in mitochondrial membrane potential, intracellular ROS accumulation, and Ca 2+ overload, and activated the cGAS-STING signaling pathway related to innate immunity. These changes had been observed at concentrations of PS-NPs as low as 60 μg/mL, which might have been comparable to environmental levels. Non-target metabolomics and Western Blotting results confirmed that PS-NPs regulated prostaglandin B1 and other metabolites to cause cell damage through the cGAS-STING pathway. Supplementation of prostaglandin B1 alleviated the immune activation and metabolic disturbance caused by PS-NPs exposure. This study identified PS-NPs-induced innate immune activation, mitochondrial dysfunction, and metabolic toxicity pathways, providing new insights into the potential for adverse outcomes of NPs in human life., 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 © 2023 Elsevier Ltd. All rights reserved.)

The acquisition of reliable knowledge about the mechanism of short laser pulse interactions with semiconductor materials is an important step for high-tech technologies towards the development of new electronic devices, the functionalization of material surfaces with predesigned optical properties, and the manufacturing of nanorobots (such as nanoparticles) for bio-medical applications. The laser-induced nanostructuring of semiconductors, however, is a complex phenomenon with several interplaying processes occurring on a wide spatial and temporal scale. In this work, we apply the atomistic-continuum approach for modeling the interaction of an fs-laser pulse with a semiconductor target, using monolithic crystalline silicon (c-Si) and porous silicon (Si). This model addresses the kinetics of non-equilibrium laser-induced phase transitions with atomic resolution via molecular dynamics, whereas the effect of the laser-generated free carriers (electron-hole pairs) is accounted for via the dynamics of their density and temperature. The combined model was applied to study the microscopic mechanism of phase transitions during the laser-induced melting and ablation of monolithic crystalline (c-Si) and porous Si targets in a vacuum. The melting thresholds for the monolithic and porous targets were found to be 0.32 J/cm 2 and 0.29 J/cm 2 , respectively. The limited heat conduction mechanism and the absence of internal stress accumulation were found to be involved in the processes responsible for the lowering of the melting threshold in the porous target. The results of this modeling were validated by comparing the melting thresholds obtained in the simulations to the experimental values. A difference in the mechanisms of ablation of the c-Si and porous Si targets was considered. Based on the simulation results, a prediction regarding the mechanism of the laser-assisted production of Si nanoparticles with the desired properties is drawn.

The production of non-toxic and homogeneous colloidal solutions of nanoparticles (NPs) for biomedical applications is of extreme importance nowadays. Among the various methods for generation of NPs, pulsed laser ablation in liquids (PLAL) has proven itself as a powerful and efficient tool in biomedical fields, allowing chemically pure silicon nanoparticles to be obtained. For example, laser-synthesized silicon nanoparticles (Si NPs) are widely used as contrast agents for bio visualization, as effective sensitizers of radiofrequency hyperthermia for cancer theranostics, in photodynamic therapy, as carriers of therapeutic radionuclides in nuclear nanomedicine, etc. Due to a number of complex and interrelated processes involved in the laser ablation phenomenon, however, the final characteristics of the resulting particles are difficult to control, and the obtained colloidal solutions frequently have broad and multimodal size distribution. Therefore, the subsequent fragmentation of the obtained NPs in the colloidal solutions due to pulsed laser irradiation can be utilized. The resulting NPs' characteristics, however, depend on the parameters of laser irradiation as well as on the irradiated material and surrounding media properties. Thus, reliable knowledge of the mechanism of NP fragmentation is necessary for generation of a colloidal solution with NPs of predesigned properties. To investigate the mechanism of a laser-assisted NP fragmentation process, in this work, we perform a large-scale molecular dynamics (MD) modeling of FS laser interaction with colloidal solution of Si NPs. The obtained NPs are then characterized by their shape and morphological properties. The corresponding conclusion about the relative input of the properties of different laser-induced processes and materials to the mechanism of NP generation is drawn.

Background: p53 wild-type lung cancer cells can develop radiation resistance. Circular RNA (circRNA) consists of a family of transcripts with exclusive structures. circRNA is critical in tumorigenesis and is a potential biomarker or therapeutic target. It is uncertain how circRNA expression and functions are regulated post-radiation in p53 wild-type cancer cells., Methods: A549 or H1299 cells were divided into p53 -wt and p53 -KO groups by CRISPR/Cas9; both groups were subjected to 4 Gy ionizing radiation (IR: p53 -wt -IR and p53 -KO -IR). RNA-seq, CCK8, cell cycle, and other functional and mechanism experiments were performed in vivo. p53 gene knockout mice were generated to test the cell results in vitro., Results: circRNAs were found in differential groups. circRNA_0006420 (IRSense) was upregulated in p53 -wt cells but had the same expression level as p53 -KO cells after radiation, indicating that p53 silencing prevents its upregulation after IR. In the presence of p53, upregulated IRSense post-radiation induces G2/M arrest by regulating DNA damage repair (DDR) pathway-related proteins. Meanwhile, upregulated IRSense post-radiation aggravates the radiation-induced epithelial-mesenchymal transition (EMT). Interestingly, in the presence of p53, it promotes IRSense/HUR/PTBP1 complex formation resulting in the promotion of the radiation-induced EMT. Moreover, c-Jun regulates the upregulation of p53 transcription after radiation treatment. For these lung cancer cells with p53, upregulated IRSense aggravates lung cancer cell proliferation and increases radiation resistance by interacting with HUR (ElAV-like protein 1) and PTBP1 (polypyrimidine tract-binding protein 1) in the nucleus., Conclusions: Lung cancer cells retaining p53 may upregulate circRNA_0006420 (IRSense) expression post radiation to form an IRSense/HUR/PTBP1 complex leading to radiotherapy resistance. This study furthers our understanding of the roles of circRNA in regulating the effect of radiotherapy and provides novel therapeutic avenues for effective clinical lung cancer therapies., 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 © 2023. Production and hosting by Elsevier B.V.)

DcAFF (discontinuous aligned fibre filament) is a novel material for fused filament fabrication (FFF) 3D printing made of highly aligned discontinuous fibres produced using high performance discontinuous fibre (HiPerDiF) technology. It reinforces a thermoplastic matrix to provide high mechanical performance and formability. Accurate printing of DcAFF poses a challenge, especially for complex geometries, because: (i) there is a discrepancy between the path where the filament experiences the adhering pressure from the filleted nozzle and the nozzle path; and (ii) the rasters display poor adhesion to the build platform immediately after deposition, which causes the filament to be dragged when the printing direction changes. This paper explains the implication of these phenomena on steering capabilities and examines the techniques for improving DcAFF printing accuracy. In the first approach, the machine parameters were adjusted to improve the quality of the sharp turning angle without changing the desired path, but this showed insignificant effects in terms of precision improvements. In the second approach, a printing path modification with a compensation algorithm was introduced. The nature of the inaccuracy of the printing at the turning point was studied with a first-order lag relationship. Then the equation to describe the deposition raster inaccuracy was determined. A proportional-integral (PI) controller was added to the equation to calculate the nozzle movement in order to bring the raster back to the desired path. The applied compensation path is shown to give an accuracy improvement in curvilinear printing paths. This is particularly beneficial when printing larger circular diameter curvilinear printed parts. The developed printing approach can be applied with other fibre reinforced filaments to achieve complex geometries.

This paper explores the use of Discontinuous Aligned Fibre Filament (DcAFF), a novel discontinuous fibre reinforced thermoplastic filament for 3D printing, to produce structural complex parts. Compared to conventional composite manufacturing, 3D printing has great potential in steering fibres around small structural features. In this current study, the initial thin carbon fibre (CF)-poly(L-lactic acid) (PLA) tape, produced with the High Performance Discontinuous Fibre (HiPerDiF) technology, is now reshaped into a circular cross-section filament, the DcAFF, using a bespoke machine designed to be scalable to high production rates rather than using a labour-intensive manual moulding method as in previous work. The filaments are then fed to a general-purpose 3D printer. Tensile and open-hole tensile tests were considered in this paper for mechanical and processability of DcAFF. The 3D printed specimens fabricated with the DcAFF show superior tensile properties compared to other PLA-based 3D printed composites, even those containing continuous fibres. Curvilinear open-hole tensile test samples were fabricated to explore the processability and performances of such material in complex shapes. The mechanical performance of the produced specimens was benchmarked against conventionally laid-up specimens with a cut hole. Although the steered specimens produced have lower strength than the fully consolidated samples, the raster generated by the printing path has turned the failure mechanism of the composite from brittle to ductile.

A new simple one-pot two-step protocol for the synthesis of 2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxylate from 2-(2-(benzylamino)benzylidene)malonate under the action of BF3·Et2O was developed. It was shown that the reaction proceeds through the formation of a stable iminium intermediate containing a difluoroboryl bridge in the dicarbonyl fragment of the molecule.

Understanding the mechanisms and controlling the possibilities of surface nanostructuring is of crucial interest for both fundamental science and application perspectives. Here, we report a direct experimental observation of laser-induced periodic surface structures (LIPSS) formed near a predesigned gold step edge following single-pulse femtosecond laser irradiation. Simulation results based on a hybrid atomistic-continuum model fully support the experimental observations. We experimentally detect nanosized surface features with a periodicity of ∼300 nm and heights of a few tens of nanometers. We identify two key components of single-pulse LIPSS formation: excitation of surface plasmon polaritons and material reorganization. Our results lay a solid foundation toward simple and efficient usage of light for innovative material processing technologies., (© 2021 Pavel N. Terekhin et al., published by De Gruyter, Berlin/Boston.)

We present a new approach to femtosecond direct laser writing lithography to pattern nanocavities in ferromagnetic thin films. To demonstrate the concept, we irradiated 300 nm thin nickel films by single intense femtosecond laser pulses through glass substrate. Using a fluence above the ablation threshold, the process is destructive, leading to the formation of an ablation crater. By progressively lowering the laser fluence, the formation of closed spallation cavities below the ablation threshold is achieved. Systematic studies by the electron and optical interferometric microscopies, supported by molecular dynamics simulations, enabled us to gain an understanding of the thermo-mechanical spallation mechanism at the solid-molten interface. We achieved the fabrication of periodic arrangements of closed spallation nanocavities. Due to their topology, closed magnetic nanocavities can support unique couplings of multiple excitations (magnetic, optical, acoustic, spintronic). Thereby, they offer a unique physics playground for emerging fields in magnetism, magneto-photonic, and magneto-acoustic applications.

A direct comparison of simulation and experimental results of UV laser-induced surface nanostructuring of gold is presented. Theoretical simulations and experiments are performed on an identical spatial scale. The experimental results have been obtained by using a laser wavelength of 248 nm and a pulse length of 1.6 ps. A mask projection setup is applied to generate a spatially periodic intensity profile on a gold surface with a sinusoidal shape and periods of 270 nm, 350 nm, and 500 nm. The formation of structures at the surface upon single pulse irradiation is analyzed by scanning and transmission electron microscopy (SEM and TEM). For the simulations, a hybrid atomistic-continuum model capable of capturing the essential mechanisms responsible for the nanostructuring process is used to model the interaction of the laser pulse with the gold target and the subsequent time evolution of the system. The formation of narrow ridges composed of two colliding side walls is found in the simulation as well as in the experiment and the structures generated as a result of the material processing are categorized depending on the range of applied fluencies and periodicities.

Gold nanoparticles (NPs) have a wide range of applications in various fields. Here, we present high-order nonlinear optical studies of the plasmas produced from ablation of Au bulk targets and Au NP films deposited on paper and glass substrates. Experimentally, we analyze high-order harmonic generation (HHG) from gold NPs-containing plasmas. The HHG is produced by 35-fs pulses at 800 and 400 nm, while the plasmas are produced by femtosecond (35 fs, 800 nm), picosecond (200 ps, 800 nm), and nanosecond (5 ns, 1064 nm) pulses, respectively. High-order harmonics produced from ablated Au NPs on paper were 40 times stronger than the HHG from that ablated from the Au bulk targets. Through molecular dynamic simulations, we investigate the formation of gold NPs during laser ablation of a metal surface under different conditions.

We present a framework based on the atomistic continuum model, combining the Molecular Dynamics (MD) and Two Temperature Model (TTM) approaches, to characterize the growth of metal nanoparticles (NPs) under ultrashort laser ablation from a solid target in water ambient. The model is capable of addressing the kinetics of fast non-equilibrium laser-induced phase transition processes at atomic resolution, while in continuum it accounts for the effect of free carriers, playing a determinant role during short laser pulse interaction processes with metals. The results of our simulations clarify possible mechanisms, which can be responsible for the observed experimental data, including the presence of two populations of NPs, having a small (5-15 nm) and larger (tens of nm) mean size. The formed NPs are of importance for a variety of applications in energy, catalysis and healthcare.

We analyzed the formation of the aluminum (Al) nanoparticles (NPs) with triangular shape obtained by ablating Al bulk in liquid using pulses with different durations (5 ns, 200 ps, and 30 fs) and wavelengths (355 nm, 800 nm, and 1064 nm). We report three stages of synthesis and aging of Al NPs: Formation, transformation, and stable stage. The NPs prepared by different pulses are almost identical at the initial stage. The effects of duration and wavelength of the ablation pulses on the aging of NPs are revealed. Pulse duration is determined to be essential for morphological transformation of NPs, while pulse wavelength strongly influences particle sizes. NPs produced by ultra-short pulses have smaller sizes and narrow size distribution. We demonstrate that oxidation and hydrolysis of Al in water are the results of ablation for all pulse durations and wavelengths, which also strongly modify the preferable reaction path of NPs in water, thus affecting the composition and morphology of triangle NPs. The results of modeling of the NPs generation in water due to a 50 ps laser pulse interacting with a thick Al target are presented. Water-based effects in the formation of NPs, their evolution, and solidification are considered from the mechanical and thermophysical points of view. The detailed analysis of the modeling results allowed for determination of the main mechanism responsible for the ablation process followed by the NPs formation., Competing Interests: The authors state that there is no conflict of interest. Funders did not participate in any part of the research.

An in vitro pharmacological evaluation of a novel dinuclear platinum complex ([KL(2)](2)[Pt(2)I(6)], where L is 3-amino-5-methyl-5-phenylhydantoin; Ad-1) was carried out. The cytotoxicity of [KL(2)](2)[Pt(2)I(6)] against human tumor cell lines was assessed using the MTT [-3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide] assay. The complex exerted concentration-dependent cytotoxic effects that were comparable or even superior to that of cisplatin. Moreover, the novel complex retained significant activity against CaCo-2 and Neuro-2A cells, which showed primary resistance to cisplatin. As evidenced by the rising level of genomic DNA fragmentation following treatment with [KL(2)](2)[Pt(2)I(6)], the cytotoxic effects are at least partly mediated by induction of apoptosis. The DNA binding of [KL(2)](2)[Pt(2)I(6)] and cisplatin were assessed using a 40-base fragment, whereby the present GG-motif is the recognition sequence of the nuclease BamH1. The DNA platination was determined after BamH1 treatment, 5% PAGE, and ethidium bromide staining. Cisplatin completely inhibited the BamH1-mediated fragmentation of the target DNA molecule. [KL(2)](2)[Pt(2)I(6)] also significantly inhibited the fragmentation of the target DNA sequence. The platination induced by [KL(2)](2)[Pt(2)I(6)] was better repaired by the nucleotide excision repair than the cisplatin lesions. As evidenced by electrophoresis mobility shift assay, the Ad-1-modified DNA was efficiently recognized and bound by the high mobility group box (HMGB)-1 protein, a member of the HMG domain proteins, which implies that the latter are most probably important for the cytotoxicity mode of action of this agent.

The velocity and nanoscale shape of the melting front are investigated in a model that combines the molecular dynamics method with a continuum description of the electron heat conduction and electron-phonon coupling. The velocity of the melting front is strongly affected by the local drop of the lattice temperature, defined by the kinetic balance between the transfer of thermal energy to the latent heat of melting, the electron heat conduction from the overheated solid, and the electron-phonon coupling. The maximum velocity of the melting front is found to be below 3% of the room temperature speed of sound in the crystal, suggesting a limited contribution of heterogeneous melting under conditions of fast heating.

The long 5-untranslated region (5'-UTR) of the human retrotransposon L1 harbors a unique internal promoter which ensures new copies of this mobile element to be much less dependent on an integration site at the level of transcription. The mechanism of this promoter's action still remains unclear, but due to some early studies the opinion has been -formed that the most important part for its function ("minimal promoter") is the first 100-150 nts of the 5'-UTR. In this paper we show that activity of the "minimal promoter" is rather poor in comparison with the entire 5'-UTR. The absolutely crucial part which is indispensable for the effective transcription is the internal region of the 5'-UTR (+390...+662) containing multiple binding sites for various transcription factors. This region may be considered as a transcriptional enhancer. Deletion of this segment leads to a dramatic lost of transcription level irrespectively of cell type, while deletion of the first 100 nt decreases the transcription efficiency no more than 1.5 to 2-fold. Thus, the organization of the L1 regulatory region may be much more similar to that of well-studied invertebrate LINE elements than it was thought before. Also we suggest a possible existence of an alternative sense promoter within the internal part of the L1 5'-UTR driving the synthesis of a 5'-truncated mRNA of the retrotransposon.

We investigated the heart rate variability (HRV) parameters in patients with rheumatoid arthritis (RA) and assessed their relationship with disease characteristics. Twenty-three female patients with RA [age 48+/-7 (mean+/-SD) years] free of cardiovascular diseases and 23 age- and gender-matched healthy controls were evaluated. After careful clinical examination, the following parameters were obtained after 24-h Holter recordings: average of all normal-to normal (NN) intervals over the entire 24-h ECG recording (meanNN, ms); the standard deviation for the time between NN complexes (SDNN, ms); the standard deviation of the average NN intervals for each 5-min period (SDANN, ms) and the square root of the mean-squared differences of successive NN intervals (rMSSD, ms). We also assessed quantitative parameters of the Poincaré plot: the standard deviation of the points perpendicular to the line-of-identity (SD1, ms); the standard deviation along the line-of-identity (SD2, ms) and their ratio (SD12). HRV parameters excluding SD2 were significantly lower in patients with RA, than in control group (p<0.05). Significant correlations of SDNN and SDANN with swollen joints count, Ritchie articular index, disease activity score (DAS) and disease duration were found. SDNN also correlated with leucocyte count and smoking. SD1 significantly correlated only with disease duration. Relationships between SDNN and smoking, swollen joints count and DAS were confirmed using multivariate analysis. Our data indicate that in patients with RA reduced HRV is independently associated with high disease activity and smoking. HRV assessment may be useful as a part of cardiovascular risk stratification in RA patients.

The kinetics and microscopic mechanisms of laser melting of a thin metal film are investigated in a computational study that combines molecular dynamics simulations with a continuum description of the laser excitation and subsequent relaxation of the conduction band electrons. Two competing melting mechanisms, homogeneous nucleation of liquid regions inside the crystalline material and propagation of melting fronts from external surfaces, are found to be strongly affected by the dynamics of the relaxation of the laser-induced pressure.

A relaxed cap-dependence of translation of the mRNA-encoding mammalian heat shock protein Hsp70 may suggest that its 5'-untranslated region (UTR) possesses an internal ribosome entry site (IRES). In this study, this possibility has been tested in transfected cells using plasmids that express dicistronic mRNAs. Using a reporter gene construct, Renilla luciferase/Photinus pyralis luciferase, we show that the 216-nt long 5'-UTR of Hsp70 mRNA acts as an IRES that directs ribosomes to the downstream start codon by a cap-independent mechanism. The relative activity of this IRES (100-fold over the empty vector) is similar to that of the classical picornaviral IRESs. Additional controls indicate that this high expression of the downstream reporter is not due to readthrough from the upstream cistron, nor is it due to translation of cryptic monocistronic transcripts. The effect of small deletions within the 5'-UTR of Hsp70 mRNA on the IRES activity varies in dependence on their position within the 5'-UTR sequence. With the exception of deletion of nt 33-50, it is small for the 5'-terminal half of the 5'-UTR and rather strong for the 3'-terminal section. However, neither of these small deletions abolishes the IRES activity completely. Excision of larger sections (>50 nt) by truncation of the 5'-UTR from the 5'-end or by internal deleting results in a dramatic impairment of the IRES function. Taken together, these data suggest that the IRES activity of the 5'-UTR of Hsp70 mRNA requires integrity of almost the entire sequence of the 5'-UTR. The data are discussed in terms of a model that allows a three-dimensional rather than linear mode of selection of the initiation region surrounding the start codon of Hsp70 mRNA.

The physiological activity of the "recombinant" bradykinin expressed by retrovirus recombinant pPS-3-neo (brd) was tested on cultural atrial (aCMC) and ventricular (vCMC) cardiomyocytes in newborn rats. The "recombinant" bradykinin was shown to have a chronotropic effect on aCMC and an inotropic effect on vCMC. The effects are in line with the action of the synthetic bradykinin preparation at a concentration of around 10(-15) M. A pretreatment of CMC by parmidine, i.e. a bradykinin antagonist, blocked the effect of bradykinin. The contractive CMC activity in the cultural cell medium, transferred by pPS-3-neo without the bradykinin gene, was not different from the control value.

Nitric oxide (NO) acts as a short-lived paracrine factor and selectively activates transcription of certain genes. The spectrum of inducible genes was studied in primary chondrocytes. A cDNA library was obtained by subtraction hybridization with RNAs isolated from rabbit chondrocytes before and after treatment with nitrosoglutathione, an NO-generating agent. Some of the cloned cDNAs were homologous to known mammalian genes and human EST. NO-dependent transcriptional activation was demonstrated for the stromelysin 1 and cyclooxygenase 2 genes and, for the first time, for mcl1 coding for an apoptosis suppressor.

The complex formation between copper(II) and the antihypertensive drug pindolol (HPin) was studied both in aqueous and methanolic media. Two complexes are formed at different metal-to-ligand molar ratios. The mononuclear complex Cu(Pin)2(HPin)2 contains two ligands in an anionic bidentate form and two--in a neutral form bound monodentately. The second complex Cu2Pin2Cl2 is dinuclear and its structure was determined by X-ray diffraction. The compound crystallizes in the monoclinic group C2/c with cell components a = 14.4998(13)A, b = 18.511(2)A, c = 14.2982(13)A, alpha = 90 degrees, beta = 109.556(2) degrees, gamma = 90 degrees and Z = 12 at 293K. A pharmacological study on the influence of pindolol and its mononuclear complex on the heart rate of rats was performed. The complex is more active and has a longer effect in comparison with the pure non-coordinated pindolol in equitoxic doses.

This review describes the systems of retroviral transfer and expression of the genes that are widely applied in basic biological research and in gene therapy. Unique features of retroviruses providing a background for construction of retroviral vectors and the methods to use these vectors are discussed.

Complexes of La(III) with 1-aminocyclopentane-, -hexane, -heptane and -4-ethylcyclohexanecarboxylic acids were obtained. The compounds were characterized by elemental analyses, IR spectroscopy and conductivity measurements. The following general formula was derived: LaL3Cl3 x 5 H2O, where L is the corresponding 1-aminocycloalkanecarboxylic acid. The pharmacological studies showed that all complexes manifested higher cytostatic and cytotoxic effects in comparison with lanthanum chloride. Much higher cytotoxic (anti-P388/D1) and cytostatic (anti-L-1210 and anti-melanoma-B16) activity was found for the lanthanum complex with 1-aminocyclopentanecarboxylic acid.

Co(II), Ni(II), Cu(II) and Zn(II) complexes of levamisole (LMS) were prepared and characterized by elemental analyses, IR spectroscopy, 1H and 13C NMR and mass spectrometry. The following general formula was derived: M(LMS)2Cl2, where M = Co, Ni, Cu, Zn. It was established that LMS behaved as a monodentate ligand and the coordination was accomplished through the N-7 atom. The toxicity and the immunomodulating activity of the complexes on mice and rats in comparison with uncomplexed LMS was assayed. The metals in the complexes exerted different changes in the toxicity of LMS. The complex containing Zn(II) was less toxic and manifested higher immunomodulating activity than LMS.

The systems acetylsalicylic acid -- potassium acetylsalicylate -- 50 wt. % ethanol -- water mixture and acetylsalicylic acid -- lithium acetylsalicylate -- 95 wt. % ethanol -- water mixture have been investigated at 15,0 degrees C. The solubility diagrams of the systems and the distribution of the components between the liquid and the crystal phases have been determined. It was established that the solutions of both systems yield hydrogen acetylsalicylates. Their crystallization fields were determined in the solubility diagrams. The hydrogen acetylsalicylates obtained were isolated as preparations under the conditions of the systems and were analyzed by chemical analysis, X-ray diffraction analysis and IR spectroscopy. These analyses are evidence of their definite composition--C9H8O4 . C9H7O4K and C9H8O4 . C9H7O4Li.

The systems C9H8O4-(C9H7O4)2Ca-25% ethanol-water mixture (I), C9H8O4-(C9H7O4)2Ca-50% ethanol-water mixture (II), C9H8O4-(C9H7O4)2Ca-95% ethanol-water mixture (III) have been investigated at 15 degrees C by physico-chemical analytical methods. It was established that under the conditions of the no experiments no double or triple compounds of acetylsalicylic acid and calcium acetylsalicylate have been formed. The fields of the crystallization of the pure components are outlined. In systems I and II there exist crystallization fields of (C9H7O4)2Ca - 2H2O and in system III field of (C9H7O4)2Ca. The anhydrous salt and the crystalline hydrate were isolated and were investigated by chemical analysis and X-ray diffraction analysis.

An analysis of some traditional techniques for the determination of the non-working level of electromagnetic radiation of meteorological radars is provided. New approaches with higher strictness of definition and formalism are proposed.