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A systematic study of extraction systems for the separation of f -elements using the tetradentate N,O-donor diamide of 1,10-phenanthroline-2,9-dicarboxylic acid ( L ) in various molecular and ionic solvents was performed. It was demonstrated that the nature of a diluent has a significant impact on solvent extraction of Am(III) and Ln(III) and the stoichiometry of formed complexes with f -elements. The mechanism of complexation and forms of complexes in different diluents were investigated by radiometric methods, UV-vis titration, and XRD.

In this work, we report on the effects observed in MAPbI 3 polycrystalline films and solar cells under moderate gamma-ray doses of 3-21 kGy. We applied several instrumental techniques such as photoluminescence spectroscopy, time-resolved photoluminescence, Suns- V OC measurement, and impedance spectroscopy to characterize exposed samples. We observed a nonlinear dependency of such characteristics as PL intensity, career lifetime, ideality factor, and recombination resistance on the exposure dose. Small doses of 3-5 kGy annihilate some of the defect centers in the material, which results in improved carrier extraction and prolonged carrier lifetime, while with larger doses of 10 kGy and above, nonradiative recombination becomes predominant. In this way, we revealed a gamma-ray threshold for MAPbI 3 films of around 10 kGy, above which it is not recommended to exploit this material. In space environment, yearly doses rarely exhibit 0.1 kGy (10 krad), and the MAPbI 3 material has a sufficient margin of safety for space applications. Moreover, this unusual behaviour opens up the opportunity to use gamma-ray sources as an effective method to improve the quality of defective polycrystalline perovskite films before actual exploitation in an ionizing radiation-free environment.

Transuranium elements such as Np, Pu and Am, are considered to be the most important radioactive elements in view of their biological toxicity and environmental impact. Concentrations of 237 Np, Pu isotopes and 241 Am in two sediment cores collected from Peter the Great Bay of Japan Sea were determined using radiochemical separation combined with inductively coupled plasma mass spectrometry (ICP-MS) measurement. The 239,240 Pu and 241 Am concentrations in all sediment samples range from 0.01 Bq/kg to 2.02 Bq/kg and from 0.01 Bq/kg to 1.11 Bq/kg, respectively, which are comparable to reported values in the investigated area. The average atomic ratios of 240 Pu/ 239 Pu (0.20 ± 0.02 and 0.21 ± 0.01) and 241 Am/ 239+240 Pu activity ratios (3.32 ± 2.76 and 0.45 ± 0.17) in the two sediment cores indicated that the sources of Pu and Am in this area are global fallout and the Pacific Proving Grounds through the movement of prevailing ocean currents, and no measurable release of Np, Pu and Am from the local K-431 nuclear submarine incident was observed. The extremely low 237 Np/ 239 Pu atomic ratios ((2.0-2.5) × 10 -4 ) in this area are mainly attributed to the discrepancy of their different chemical behaviors in the ocean due to the relatively higher solubility of 237 Np compared to particle active plutonium isotopes. It was estimated using two end members model that 23% ± 6% of transuranium radionuclides originated from the Pacific Proving Grounds tests, and the rest (ca. 77%) from global fallout., 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 Ltd. All rights reserved.)

The concentration and sorption behavior of 237 Np on the bottom sediments of water bodies in the Far East region of Russia (Lake Khanka and Peter the Great Bay) were studied for the first time. The 237 Np concentrations vary from 1.06 × 10 -6 to 4.43 × 10 -5 mBq g -1 in the bottom sediments of Lake Khanka and from 1.05 × 10 -4 to 2.52 × 10 -3 mBq g -1 for Amur Bay. The experiment on the adsorption of Np on marine and lake sediment showed that it is sorbed through complexation with silicates (albite, leucite). The Np sorption isotherm on marine sediments is described by the Langmuir equation; the distribution coefficients (Kd) of Np vary from 57 to 588 mL g -1 . For lake sediments, the isotherm is described by the Henry equation; the Kd value reaches 935 mL g -1 ., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Kuzmenkova Natalia reports financial support was provided by Russian Science Foundation. Hou Xiaolin reports financial support was provided by National Natural Science Foundation of China. Co-author is an assocaited editor in Journal of Environmental radioactivity., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A variant of microfluidic setup design for the study of extraction kinetics has been proposed. Mass transfer constants for Am(III) and Eu(III) and observed rate constants were obtained for N-,O-donor ligands featuring phenanthroline and bipyridyl cores. The possibility of determining rate constants for cations independently of each other makes it possible to observe the kinetic effect of separation. The extraction rate was found to be lower for the bipyridyl ligand, compared to phenanthroline. The values of the rotation barriers for the ligands were calculated using the DFT method. The values correlate with the obtained low extraction rate for the bipyridyl ligand. Also, crystallographic data showing anti-conformation for the bipyridyl ligand align with the kinetic data. Surface tension was also determined for the systems with the studied ligands. It is shown that at equal ligand concentrations, the value of surface tension agrees with the extraction rate. Furthermore, it is shown that for the bipyridyl ligand, prior contact of the organic phase with nitric acid significantly affects the surface tension.

A highly efficient synthetic approach was developed for the synthesis of unsymmetrical 1,10-phenanthroline-2,9-diamides with two different substituents in the fourth and seventh positions of the phenanthroline core. The structures of these ligands were confirmed using various spectral methods including 2D-NMR and X-ray analysis. Quantum chemical calculations supported the presence of tautomeric forms of these ligands. Furthermore, it was discovered that these compounds exhibit polydentate ligand behavior toward lanthanide nitrates. The structural characteristics of the complexes formed between these ligands and lanthanide nitrates were investigated both in the solid state and in solution. To further understand the binding properties of these novel unsymmetrical ligands, the binding constants for potential complexes were quantitatively measured by using UV-vis spectrophotometric titration. This allowed for a comprehensive analysis of the binding affinity and stability of these complexes. Extraction experiments of f -elements were performed for symmetrical and unsymmetrical diamides. Overall, this study presents significant advancement in the synthesis and characterization of unsymmetrical 1,10-phenanthroline-2,9-diamides and provides valuable insights into their potential applications as polydentate ligands for lanthanide nitrates.

In this study, pyridine and phenanthroline diphosphonate ligands were investigated for the first time from the context of solvent extraction and potentiometric sensing of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(II) cations. The extraction efficiency under the same conditions for phenanthroline-diphosphonates is considerably higher than that for pyridine ligands. At the same time, the pyridine-diphosphonates show pronounced selectivity towards lead in this metal series. The extraction systems with phenanthroline diphosphonates provided the most efficient extraction of Cd(II) and Pb(II) cations ( D > 90). The newly developed pyridine and phenanthroline diphosphonate ligands have proven to be highly effective components in plasticized polymeric membranes. These ligands can be utilized to construct potentiometric ion sensors that exhibit a notable response specifically towards Pb(II) cations. Among the previously reported tetradentate ligands, the phenanthroline diphosphonate ligand, when incorporated into plasticized polymeric membranes, demonstrated the highest sensitivity towards d-metals and Pb(II). The structure of the single crystal complex of Pb(II) and Cd(II) with pyridine-diphosphonates was studied by X-ray diffraction analysis (XRD). The geometry of Cu(II), Zn(II), Cd(II) and Pb(II) complexes and the energy effect of the complex formation, including pseudo-oligomerization reactions, were determined by DFT calculations. The high sensing and extraction efficiency of diphosphonates with respect to Pb(II) is consistent with the minimum values of complex formation energies. The variation in sensory and extraction properties observed among the studied diphosphonate ligands is influenced by the ability to form polynuclear complexes with Pb(II) cations, whereas such properties are absent in the case of Cd(II) cations.

A reaction of acyl chlorides derived from 1,10-phenanthroline-2,9-dicarboxylic acids with piperazine allows the preparation of the corresponding 24-membered macrocycles in good yield. The structural and spectral properties of these new macrocyclic ligands were thoroughly investigated, revealing promising coordination properties towards f-elements (Am, Eu). It was shown that the prepared ligands can be used for selective extraction of Am(III) from alkaline-carbonate media in presence of Eu(III) with an SF Am/Eu up to 40. Their extraction efficiency is higher than calixarene-type extraction of the Am(III) and Eu(III) pair. Composition of macrocycle-metal complex with Eu(III) was investigated by luminescence and UV-vis spectroscopy. The possibility of such ligands to form complexes of L:Eu = 1:2 stoichiometry is revealed.

Three pyrrolidine-derived phenanthroline diamides were studied as ligands for lutetium trinitrate. The structural features of the complexes have been studied using various spectral methods and X-ray. The presence of halogen atoms in the structure of phenanthroline ligands has a significant impact on both the coordination number of lutetium and the number of solvate water molecules in the internal coordination sphere. The stability constants of complexes with La(NO 3 ) 3 , Nd(NO 3 ) 3 , Eu(NO 3 ) 3 , and Lu(NO 3 ) 3 were measured to demonstrate higher efficiency of fluorinated ligands. NMR titration was performed for this ligand, and it was found that complexation with lutetium leads to an approximately 13 ppm shift of the corresponding signal in the 19 F NMR spectrum. The possibility of formation of a polymeric oxo-complex of this ligand with lutetium nitrate was demonstrated. Experiments on the liquid-liquid extraction of Am(III) and Ln(III) nitrates were carried out to demonstrate advantageous features of chlorinated and fluorinated pyrrolidine diamides.

Phenanthroline diamides ( L ) demonstrated a unique ability to extract uranium from nitric acid solutions into a polar organic solvent forming complexes of 1:2 stoichiometry as tight ion pairs {[UO 2 L NO 3 ] + [UO 2 (NO 3 ) 3 ] - } by a novel extraction mechanism, which is a combination of two already well-known mechanisms: solvation and ion-pair anion exchange. A UV-vis study was used to confirm the formation of such complexes directly in the organic phase. Moreover, chemical synthesis and single crystal growth were performed to confirm unambiguously the structure of the complexes in the solid state.

The fact of the fracture of the extraction curve of lanthanides by 1,10-phenanthroline-2,9-diamides is explained in terms of the structure of complexes, solvent extraction data and quantum chemical calculations. The solvent extraction proceeds in two competing directions: in the form of neutral complexes L Ln(NO 3 ) 3 and in the form of tight ion pairs {[ L Ln(NO 3 ) 2 H 2 O] + (NO 3 - ).

The fractionation of high-level radioactive waste from nuclear power plants simplifies the handling of its components, and facilitates the reduction of radiotoxic effects on the environment. The search and study of new ligands for solvent extraction, as one of the methods in fractionation, remains a complex and important research task. In this work, four pyridine diphosphonate ligands were synthesized. These ligands are part of the class of the N,O-donor extractants, which are selective towards Am(III). The separation factor SF(Am/Eu) for the best extractant reached values up to 10. The influence of the substituents on the efficiency of extraction and complexation of trivalent f-elements, the kinetics of extraction, and the behavior of the ligand at the interface were described. The effect of nitric acid concentration on the extraction was shown. The stoichiometry of the complexes was determined by slope analysis in solvent extraction experiment and verified by spectrophotometric titration in acetonitrile. Liquid tension experiments with a pendant drop method revealed the interfacial properties of the ligands in "F-3 solvent/H 2 O" and "F-3 solvent/HNO 3 " systems. The relationship between the surface activity and the ligand structure was shown. Studies of the extraction kinetics were performed in a modified Lewis cell. The effect of the ligand structure on the extraction rate was shown. The DFT calculation with the B3LYP density functional was used to explain the extraction properties of the ligands, including selectivity. The calculation of the pre-organization energy of the ligands explained the kinetics and extraction patterns for the studied series.

The first examples of 1,10-phenanthroline-2,9-diamides bearing CF 3 -groups on the side amide substituents were synthesized. Due to stereoisomerism and amide rotation, such complexes have complicated behavior in solutions. Using advanced NMR techniques and X-ray analysis, their structures were completely elucidated. The possibility of the formation of complex compounds with lanthanoids nitrates was shown, and the constants of their stability are quantified. The results obtained are explained in terms of quantum-chemical calculations.

Reprocessing of spent nuclear fuel (SNF) is an important task in a frame of ecology and rational use of natural resources. Uranium, as the main component of SNF (>95%), can be recovered for further use as fresh nuclear fuel. To minimize an amount of solid radioactive waste generated during SNF reprocessing, new extractants are under investigation. Diamides of 1,10-phenanthroline-2,9-dicarboxylic acid are perspective tetradentate N-donor ligands that form strong complexes with f -elements, which are soluble in polar organic solvents. As an example of three ligands of this class, we conducted a comparative study and showed how the substituent in the amide functional group affects the extraction ability toward uranyl nitrate from nitric acid media. We have performed a careful study (NMR, FT-IR, XRD, RMC-EXAFS) of the structures of synthesized complexes of new ligands with uranyl nitrate and used quantum mechanical calculations to explain the discovered regularities through.

Hybrid donor extractants are a promising class of compounds for the separation of trivalent actinides and lanthanides. Here, we investigated a series of sterically loaded diphosphonate ligands based on bipyridine (BiPy-PO-iPr and BiPy-PO-cHex) and phenanthroline (Phen-PO-iPr and Phen-PO-cHex). We studied their complex formation with nitrates of trivalent f-elements in solvent extraction systems (Am and Eu) and homogeneous acetonitrile solutions (Nd, Eu, and Lu). Phenanthroline extractants demonstrated the highest efficiency and selectivity [ SF (Am/Eu) up to 14] toward Am(III) extraction from nitric acid solutions among all of the studied diphosphonates of N-heterocycles. The binding constants established by UV-vis titration also indicated stronger binding of sterically impaired diphosphonates compared to the primary substituted diphosphonates. NMR titration and slope analysis during solvent extraction showed the formation of 2:1 complexes at high concentrations (>10 -3 mol/L) for phenanthroline-based ligands. According to UV-vis titrations at low concentrations (10 -5 -10 -6 mol/L), the phenanthroline-based ligands formed 1:1 complexes. Bipyridine-based ligands formed 1:1 complexes regardless of the ligand concentration. Luminescence titrations revealed that the quantum yields of the complexes with Eu(III) were 81 ± 8% (BiPy-PO-iPr) and 93 ± 9% (Phen-PO-iPr). Single crystals of the structures [Lu(μ 2 ,κ 4 -(iPrO) 2 P(O)Phen(O) 2 (OiPr))(NO 3 ) 2 ] 2 and Eu(Phen-PO-iPr)(NO 3 ) 3 were obtained by chemical synthesis with the Phen-PO-iPr ligand. X-ray diffraction studies revealed a closer contact of the f -element with the aromatic N atoms in the case of sterically loaded P═O ligands compared with sterically deficient ligands. Density functional theory calculations allowed us to rationalize the observed selectivity trends in terms of the bond length, Mayer bond order, and preorganization energy.

Development of efficient extractants for the separation of actinides and lanthanides in the technologies of nuclear fuel cycle is one of the most urgent and complex tasks in modern nuclear energetics. New family of 4,7-dichloro-1,10-phenanthroline-2,9-dicarboxylic acid diamides based on cyclic amines was synthesized and shown to exhibit high selectivity in the La/Am pair separation (SF (Am/La ≈ 10)) and in the Am/Eu pair separation (SF (Am/Eu ≈ 12)). It was shown that pyrrolidine derived diamide is more efficient extractant for americium, curium and lanthanides from highly acidic HNO 3 solution than its non-cyclic N , N , N ', N '-tetraalkyl analogues. The structures of synthesized compounds were studied in details by IR, NMR spectroscopy, and single crystal X-ray diffraction. According to spectroscopy data, incorporation of aromatic rings to the amide fragment of ligand leads to complex dynamic behavior in solutions what is believed to strongly affect the extraction ability of synthesized ligands., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this work, we report a comparative study of the gamma ray stability of perovskite solar cells based on a series of perovskite absorbers including MAPbI 3 (MA = methylammonium), MAPbBr 3 , Cs 0.15 FA 0.85 PbI 3 (FA = formamidinim), Cs 0.1 MA 0.15 FA 0.75 PbI 3 , CsPbI 3 , and CsPbBr 3. We reveal that the composition of the perovskite material strongly affects the radiation stability of the solar cells. In particular, solar cells based on the MAPbI 3 were found to be the most resistant to gamma rays since this perovskite undergoes rapid self-healing due to the special gas-phase chemistry analyzed with ab initio calculations. The fact that the solar cells based on MAPbI 3 can withstand a 1000 kRad gamma ray dose without any noticeable degradation of the photovoltaic properties is particularly exciting and shifts the paradigm of research in this field toward designing more dynamic rather than intrinsically robust (e.g., inorganic) materials.

Phosphonate based ligands are well known for the extraction of 'f' block elements. Three N,O-donor N-heterocyclic aromatic diphosphonate ligands were evaluated in the present work for the extraction/separation studies of Am 3+ and Eu 3+ . Complexation studies in aqueous medium using luminescence titration indicated the formation of anionic complexes in the case of Eu 3+ . Two phase liquid-liquid extraction studies were, therefore, carried out by employing Aliquat-336 as the liquid anion exchanger. The results indicated the formation of a species with a metal-ligand stoichiometry of 1 : 3 in the case of pyridine-2,6-diphosphonic acid (PyPOH). In the case of 2,2'-bipyridine-6,6'-diphosphonic acid (BipyPOH), however, a 1 : 2 complex was extracted and 1,10-phenanthroline-2,9-diphosphonic acid (PhenPOH) extracts the Am 3+ and Eu 3+ ions by forming both 1 : 2 and 1 : 3 complexes. Formation of these kinds of anionic complexes was further confirmed using electrospray ionization mass spectrometry (ESI-MS). DFT calculations predicted the structure of the anionic complexes. The non-selectivity of these kinds of ligands between Am 3+ and Eu 3+ was attributed to the presence of unfavorable covalent interactions in the metal-ligand bonds.

We explored the radiation stability of carbazole-based electron-donor conjugated polymers, acceptor fullerene derivative [60]PCBM, and their blends as active layer components of organic solar cells. An exposure to γ rays induced evident degradation effects in bulk samples of the pristine fullerene acceptor ([60]PCBM) and two investigated electron-donor conjugated polymers: PCDTBT and PCDTTBTBTT. The most severe radiation damage occurred in [60]PCBM as can be concluded from the significant losses in open circuit voltage, fill factor, and efficiency of photovoltaic (PV) devices comprising the exposed fullerene acceptor. Conjugated polymers PCDTBT and PCDTTBTBTT showed substantially different radiation stabilities: the samples of PCDTTBTBTT exposed to 200 Gy lost ∼25% of their nominal photovoltaic efficiency due to a substantial decay of all device parameters, while PCDTBT alone showed just a minor aging under the same conditions. The fullerene-polymer composites were much more resistant with respect to the radiation damage than the bulk samples of pristine materials. In particular, the PCDTBT/[60]PCBM composite films demonstrated an outstanding radiation stability while maintaining more than 80% of the initial photovoltaic efficiency after exposure to γ rays with a maximum absorbed dose of 6500 Gy. Considering an average annual radiation dose of 160 Gy according to the NASA estimations for satellites at geocentric Earth orbits, organic solar cells based on PCDTBT/[60]PCBM blends hold a promise to deliver lifetimes well above 10 years. The revealed impressive radiation stability of PCDTBT/[60]PCBM blends in combination with other advantages of organic solar cells, for example, their mechanical flexibility and lightweight, points to a bright future of this PV technology in space industry applications.

We report on the impact of γ radiation (0-500 Gy) on triple-cation Cs 0.15 MA 0.10 FA 0.75 Pb(Br 0.17 I 0.83 ) 3 perovskite solar cells. A set of experiments was designed to reveal the individual contributions of the hole-collecting bottom electrode, perovskite absorber, and electron transport layer (ETL) to the overall solar cell degradation under radiation exposure. We show that the glass/ITO/PEDOT:PSS hole-collecting electrode withstands a 500 Gy dose without any losses in the solar cell performance. In contrast, the perovskite absorber films and PC 61 BM ETL are very sensitive to γ rays, as can be concluded from the radiation-induced decay of the solar cell efficiency by ∼32-41%. Red shift of the perovskite emission bands and strong enhancement of the photoluminescence suggest that γ rays induce phase segregation of iodine-rich and bromine-rich domains, which represents the first reported example of the radiation-induced halide phase separation in perovskite films. The degradation pathway revealed here emphasizes the need for developing a new generation of metal halide absorbers and ETL materials with improved radiation stability to enable potential space applications of perovskite photovoltaics.

A new phosphine oxide ligand demonstrates high selectivity for the Am-Cm pair with SF = 2.9-3.5 and the Am-Eu pair with SF = 7.3-8.5 in a range of 0.1-3 M nitric acid. Thermodynamic measurements show that the entropy factor is responsible for selectivity observed in the extraction experiment. The most prevalent complexes of all three metal ions were (Ph2PyPO)2M(NO3)3. According to their DFT modelling, the M-N distances for the Cm ion were larger than those for Am, so the last ion enters deeper into the pseudo-cavity of the ligand, which causes the observed selectivity.

A new, previously unused combination of the high magnetic field side probing and the lower extraordinary mode cutoff was used in the T-10 tokamak for the electron density profile measurements by using a frequency modulation continuous wave reflectometer. This scheme has a significant advantage for large fusion machines where flat electron density profiles and high electron temperatures are expected. The reflectometer design is based on a common scheme with voltage controlled oscillators, active multipliers, and in-phase/quadrature signal detection. Iterative procedures were applied to calibrate a microwave source frequency and compensate the dispersion of probing signals in the conventional rectangular waveguides used as the transmission lines. About 0.2% stability of the beating frequency was reached after the calibration procedure had been finished. An advanced finite-difference scheme was proposed for the reconstruction of the electron density profile to reduce errors and improve the overall performance of the algorithm. Reconstructed electron density profiles demonstrate good agreement with conventional T-10 diagnostic data. Some specific technical and physical aspects of the diagnostic were also discussed on the basis of T-10 operation experience.

The X-ray photoelectron spectral structure of CeO2 valence electrons in the binding energy range of 0 to ∼50 eV was analyzed. The core-electron spectral structure parameters and the results of relativistic discrete-variational calculations of CeO8 and Ce63O216 clusters were taken into account. Comparison of the valence and the core-electron spectral structures showed that the formation of the inner (IVMO) and the outer (OVMO) valence molecular orbitals contributes to the spectral structure more than the many-body processes. The Ce 4f electrons were established to participate directly in chemical bond formation in CeO2 losing partially their f character. They were found to be localized mostly within the outer valence band. The Ce 5p atomic orbitals were shown to participate in the formation of both the inner and the outer valence molecular orbitals (MOs). A large part in the IVMO formation is taken by the filled Ce 5p1/2, 5p3/2 and O 2s atomic shells, while the Ce 5s electrons participate weakly in the chemical bond formation. The composition and the sequent order of the molecular orbitals in the binding energy range of 0 to ∼50 eV were established. A quantitative scheme for the molecular orbitals of CeO2 was built. This scheme is fundamental for understanding the nature of chemical bonding and also for the interpretation of other X-ray spectra of CeO2. Evaluations revealed that the IVMO electrons weaken the chemical bond formed by the OVMO electrons by 37%.

Aim: To study the results of intraperitoneal chemoperfusion combined with cytoreductive procedure in patients with peritoneal pseudomyxoma., Material and Methods: For the period 2006--2015 seven patients with peritoneal pseudomyxoma underwent aggressive treatment using hyperthermic intraperitoneal chemoperfusion combined with cytoreductive procedure at the Department of General Oncology of N.N. Petrov Research Institute of Oncology., Results: Two patients had postoperative complications. One of them died after 12 days postoperatively. Features of postoperative complications were predominantly determined by volume of cytoreduction. Advanced tumoral process caused death in 2 patients additionally. Other patients are still alive during 4--28 months after surgery., Conclusion: Hyperthermic intraperitoneal chemoperfusion combined with cytoreductive procedure is advisable for peritoneal pseudomyxoma to improve survival. Optimal cytoreduction should be developed in researches with large number of patients to decrease incidence of complications.

The study of pharmacokinetics of melphalan in the perfusate and blood plasma during isolated limb regional perfusion (ILRP) was carried out in patients with melanoma (n=21) and soft tissue sarcoma (n = 24). Melphalan was administered as 10 mg/l for a lower extremity and 13 mg/l for a upper extremity. Quantification of melphalan in perfusate and blood samples was performed by means of liquid chromatography/tandem mass spectrometry. 30 samples of the perfusate and 27 venous blood samples were analyzed. During the first 5 minutes of ILRP concentration of melphalan in the perfusate decreased to 13.2% of the initial value, and by the end of perfusion (60 minutes) it was 3.3%. The amount of melphalan in the blood plasma of the patients by the end of ILRP wasn't higher than 1.6% from the administered dose. That demonstrates minor systemic absorption of the drug during ILRP. Moreover melphalan concentration in the blood plasma during the perfusion was in average 0.015-0.223 mg/l which is significantly lower compared to the blood plasma concentrations after intravenous administration of melphalan. Thus ILRP procedure provided 97% of the melphalan dose accumulation in the soft tissues of a limb and in tumor tissues. Also pharmacokinetic advantage of melphalan over systemic administration of the drug was shown.

A steady increase of incidence of skin melanoma and soft tissue sarcomas of the extremities currently continues to be observed. Taking into account the high probability of developing of locally disseminated forms of skin melanoma and soft tissue sarcomas of extremities, the need to use combined methods in their treatment is quite high. In the 21st century the possibility of a use of isolated regional chemoperfusion provides a high objective response of tumor to chemotherapy without their systemic impact and improves the quality of life through preservation of the limb. This review describes the currently used drugs, and the results of ongoing clinical research in the world, as well as the results of our own study.

An analyzed cohort consists of 50 pediatric patients with osteosarcoma receiving combined therapy in N. N. Petrov Research Institute for Oncology (1999-2010). Thirty nine of them had localized disease, 11 patients had distant metastases. The treatment scheme included neoadjuvant therapy with cisplatin and doxorubicin, surgical treatment and adjuvant therapy depended on initial response and could include cisplatin, doxorubicin, high-dose methotrexate, ifosfamide, etoposide. Four-year overall and relapse-free survival in children with localized disease was 74.3% and 69.2% accordingly. In 62% of patients were performed organ-preserving surgical interventions, in 22 patients was performed endoprosthetics, in 4 patients the defect was replaced by a bone autograft on a vascular bundle. The effectiveness of initial treatment and secondary endoprosthetics were analyzed. Six patients with lung metastases received normotermic lung chemoperfusion, 4 of them are alive and disease-free for 8 to 24 months.

The article presents 3 methods of operative reconstruction of the shoulder stump for improving the conditions of prosthesis without fixation of the prosthesis at the level of the shoulder joint. The methods were used in 42 patients and gave good functional results.

Long-term results were followed up from 3 to 15 years in 649 patients with different morphological forms of the nodular goiter. Postoperative recurrent nodular goiter was diagnosed in 26.8% of the patients. The greater part of recurrences (87.4%) was nodular colloid goiter that was shown morphologically. Main part of the recurrences (69.1%) appeared after operations if the greater part of the thyroid gland was left--resection of a lobe and enucleation of the nodes. No recurrences were registered after thyroidectomy. The results of the investigation suggest that such operations as enucleation of a node and resection of a lobe with a node are thought to be inadequate.

Thirty patients with colon disease in need of urgent surgery have undergone resection of the colon with formation of terminal afferent colostomy and compressive colon-colon anastomosis using oval and linear nikelid-titanium implants. Complications were seen in 6 (20%) patients, lethality was 6,7% due to multiorgan failure in the presence of generalized peritonitis. There were no complications due to colon-colon anastomosis. The above method permits one to reduce surgical trauma of future reconstructive surgeries.

One of the most common health criteria--erythrocyte sedimentation rate (ESR)--is considered in the paper. It is shown that the simple model presented, based on the generalized Stokes formula, the blood volume conservation law, and the Smoluchowski theory of particles coagulation, makes it possible, on the basis of experimentally recorded sedimentation curves, to identify quantitatively the values of the essential physical parameters of the coupled processes of erythrocyte aggregation and sedimentation. The analytical solution of Smoluchowski equation is used to evaluate the sedimentation and aggregation rate constants. The problem of determining the erythrocyte aggregation rate (EAR) is transformed to a minimization task in which only the experimental results for ESR are needed. Experimentally ESR is measured accurately enough by using an equipment set up just for the purpose. This method of identification could be used as a diagnostic test in hematological laboratories.

To analyse parametrically (in terms of the qualitative theory of dynamical systems) the mechanical influence of inertia, resistance (positive and negative), elasticity and other global properties of the heart-muscle on the left ventricular pressure, an active rheodynamic model based on the Newtons's principles is proposed. The equation of motion of the heart mass centre is derived from an energy conservation law balancing the rate of mechanical (kinetic and potential) energy variation and the power of chemical energy influx and dissipative energy outflux. A corresponding dynamical system of two ordinary differential equations is obtained and parametrically analysed in physiological conditions. As a result, the following main conclusion is made: in physiological norm, because of the heart electrical activity, its equilibrium state is unstable and around it, mechanical self-oscillations emerge. In case the electrical activity ceases, an inverse phase reconstruction occurs during which the unstable equilibrium state of the system becomes stable and the self-oscillations disappear.

Wide excision of neoplasm is most frequently used in surgery for soft tissue tumors, on appropriate sites and whenever the "envelope" can be preserved. The most frequent site of pelvic girdle soft-tissue tumors was the glutal area (39.0 +/- 4.8%). Out of 100 patients with such sarcomas, wide excision of tumor was performed in 82, and tumor excision + bone resection--18. The former procedure was mostly used in the management of liposarcomas (26.5 +/- 4.2%), while the latter--in synovial sarcoma (33.3 +/- 4.9%).

The well-known S-shaped settling curves are obtained as solutions of an autonomic dynamical system deduced mathematically from the generalized Stokes formula, the blood volume conservation law, and the Smoluchowski theory of particle coagulation. Numerical computations and parametric analysis of the deduced two nonlinear differential equations for the plasma zone thickness and aggregate size are given. It is shown that the model presented makes it possible, on the basis of experimentally recorded sedimentation curves and aggregate size growth, to identify quantitatively the values of the essential physical parameters of the coupled processes of erythrocyte aggregation and sedimentation. This method of identification could be used as a diagnostic test in hematological laboratories.

There have been studied 1037 cases of hand and finger punch injuries, observed in 786 victims. An analysis of the trauma causes allowed to carry out the complex of preventive measures. The efficiency of these measures is testified by 3-fold decrease of occupational traumatism at Lysvensk metal works during 5 recent years. It has been stated that 496 (52.6%) of 945 finger and hand wounds were tissue avulsion and crush. These damages are typical ones in case of finger injuries with a punch. There have been analysed the results of treatment of 341 patient with scalped wounds, open fractures, finger and hand avulsions and crushes (482 wounds). It has been stated that careful surgical treatment of a wound with edge dissection, removal of damaged fatty tissue and free fractured fragments is a reliable method of infectious complication prophylaxis when the wound has been stitched without intention and the skin defects closed by means of the first skin plasty. The first skin plasty has been used for treatment of 62 wounds. Complete graft survival has been noted in 70.9% cases. In 85% of cases there have been obtained good functional results. A special section of sparing treatment presents finger replantation in case of their avulsion. Microsurgical technique has been applied with 9 patients. There have been replanted 13 fingers and 1 hand (survived 10 fingers and the hand). There have been revascularized 3 fingers (2 of them have survived).

The outfit is intended for cutting, coagulation and microcoagulation of the biological tissue by high-frequency current during surgical interventions in stomatology. The outfit ensures smooth control of outlet power. It is fitted out with a timer for automatic time lag of electrosurgical exposure. The generator is triggered by pressing the pedal or push button of the electrode holder. The outfit is also equipped with a kit of instruments. A short technical specification of the outfit is given.

The authors have proposed a method of fixation of an autodermal graft by using a net sewn to the healthy skin areas with single knot sutures and a method of autodermatoplasty of extensive defects of the soft tissues of the extremities. These methods have been successfully used in 29 patients. There have been no complications.

A brief analysis has been made of the basic operational features of the high-frequency electrosurgical endoscopy apparatus (HFEA). Recommendations for choosing the output parameters are given, the solution of the problem of designing HFEA for endoscopy was considered by using the "Endotome-I" apparatus as an example.