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Hierarchical micro/nanostructured composites, which contain iron and/or its (hydr)oxides, demonstrate high rate and capacity of arsenic adsorption. The main objective of this paper is the use of novel low toxicity AlOOH/AlFe hierarchical micro/nanostructures for arsenic removal. AlOOH/AlFe composite was obtained by simple water oxidation in mild conditions using AlFe bimetallic nanopowder as a precursor. AlFe bimetallic nanopowder was produced by electrical explosive of two twisted wires in argon atmosphere. The productivity of the electrical explosion assembly was 50 g/h, with the consumption of the electrical energy was 75 kW·h/kg. AlFe bimetallic nanoparticles were chemically active and interacted with water at 60 °C. This nanocomposite AlOOH/AlFe is low cost and adsorbs more than 200 mg/g As(V) from its aqueous solution. AlOOH/AlFe composite has flower-like morphology and specific surface area 247.1 m2/g. The phase composition of nanostructures is present AlOOH boehmite and AlFe intermetallic compound. AlOOH/AlFe composite was not previously used for this. The flower-shape AlOOH morphology not only facilitated deliverability, but increased the As(V) sorption capacity by up to 200 mg/g. The adsorption kinetics has been found to be described by a pseudo-second-order equation of Lagergren and Weber-Morris models while the experimental adsorption isotherm is closest to the Freundlich model. This indicates the energy heterogeneity of the adsorbent surface and multilayer adsorption. The use of non-toxic nanostructures opens up new options to treat water affected by arsenic pollution.

Backgroundrecurrent ovarian cancer (OC) patients with platinum-free interval (PFI) Methodswe queried the PubMed database for all full-text articles and abstracts on the treatment of patients with platinum-resistant ovarian cancer (PROC) in 01/01/2000-01/06/2019 timeframe. The PRISMA tool was used to ensure transparent reporting of the results. Inclusion criteria were: 1) morphologically confirmed epithelial ovarian cancer; 2) recurrent disease within 6 months after completion of platinum-based chemotherapy; 3) treatment with platinum- or non-platinum chemotherapy with agents that are routinely used for OC; 4) no concomitant therapy with targeted or investigational agents or non-platinum doublets; 5) defined response rate (RR) and assessment criteria. Proportion meta-analysis (random-effect model) and beta-regression were conducted to assess the impact of platinum agents on response rate as well as significance of other variables. In the beta-regression model response rate was a dependent variable, while platinum agents (yes or no), used non-platinum drugs and method of response assessment were independent variables. Statistical analysis was dose with meta, metafor and betareg packages of R software.Resultswe identified 7156 articles and screened them for title and abstract, 157 studies for further analysis. Overall, 6327 patients were included in the analysis, efficacy of non-platinum- and platinum-based therapy was assessed in 113 (n = 5272) and 44 (n = 1055) trials respectively. In meta-proportion random-effect model RR among patients treated with platinum-based and non-platinum chemotherapy RR was 36% (95% CI 30-41; I2 = 62%) and 16% (95% CI 14-19; I2=70%) respectively. For sensitivity analysis various regression models were made with different subsets of the trials and additional variables (including year of the trial, percentage of serous subtype of OC and median of prior therapy lines). Platinum was the strongest predictor of response in every developed model.Conclusionthis meta-analysis shows that patients with ‘platinum-resistant’ ovarian carcinoma may derive significant benefit from reintroduction of platinum agents. These results support recent ESMO-ESGO consensus on treatment of recurrent ovarian cancer.

Bimetallic Al–Cu and Al–Ag nanoparticles were synthesized by electric explosion of wires in an argon atmosphere. The mass ratio of aluminum and the second metal (Me = Cu or Ag) was ~ 90 : 10 and was controlled by the diameter of the dispersed metal wires. Mesoporous AlOOH–Me nanocomposite was obtained by simple oxidation of Al–Me precursors with water at a temperature of 60°С. The kinetic regularities of the oxidation of Al–Me nanoparticles in dilute aqueous suspensions were studied. The effect of the second metal on the structure, morphology, and antibacterial activity of nanocomposites against methicillin-resistant Staphylococcus aureus (MRSA) bacteria was studied. It has been shown that the synthesized AlOOH–Me nanocomposites possess high antibacterial activity and are promising and highly efficient antimicrobial agents.

Electric explosion of zinc and silver intertwined wires in an oxygen-containing atmosphere was used for the first time to produce ZnO–Ag bicomponent nanoparticles. Silver content was regulated by wire diameters. The nanoparticles were characterized by transmission electron spectroscopy, X-Ray diffraction. Optical properties of ZnO–Ag nanoparticles were studied by ultraviolet–visible spectroscopy. The phase state of nanoparticles in the range of high (12–35%) silver content has been established, which provides an increase in the photocatalytic activity in the visible spectral range. The Methylene blue degradation efficiency by ZnO-12Ag nanoparticles reached 90%, which was higher than that of ZnO nanoparticles produced by electric explosion of zinc wire. Composites had high antibacterial activity against Escherichia coli bacteria.

Currently, soft hydrogels with antimicrobial properties are widely used in biomedical applications as dressings and wound healing agents. In the present work, Cu–Fe nanoparticles with different component ratios were obtained by the joint electric explosion of iron and copper wires in an argon atmosphere. Bimetallic nanoparticles had a clear interface between the iron and copper phases at the particle level. Cu–Fe nanoparticles had high antibacterial activity against a wide bacterial spectrum. In connection with dusting and entrainment of nanoparticles, for the convenience of biomedical application, compositions were created based on non-toxic biocompatible polymers – polyvinyl alcohol, polyacrylic acid, and polyacrylamide. The suspension of nanoparticles was pretreated with ultrasound for 5 min at a frequency of 22.4 kHz. Polyvinyl alcohol was used as a nanoparticle stabilizer. The stability of the suspension was investigated by the sedimentation method. The resulting compositions effectively inhibited the growth of Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, methicillin-resistant Staphylococcus aureus ATCC 43300 (MRSA), and Pseudomonas aeruginisa ATCC 9027.

Norway spruce (Picea abies) and Siberian spruce (P. obovata) are among the most important forest-forming coniferous species in the boreal part of Eurasia. Despite numerous publications on the taxonomy of Norway spruce and closely related taxa (P. obovata Ledeb. and P. fennica (Regel) Kom.), the problem of their identification, as well as clarification of their taxonomic status, has not been solved so far. Species delimitation is particularly challenging when P. abies, P. obovata and P. fennica occur in sympatry. Our study aims to assess taxonomic value of proposed earlier and search for stable diagnostic characters of cones and their scales to distinguish Picea abies and its sympatric in the North-West of Russia P. fennica and P. obovata. In addition, we analyzed and updated information on geographical distribution and phytocenotic characteristics of the above-mentioned species in the North-West of the European part of Russia. We examined herbarium specimens and cones sampled from 88 trees from 22 Picea stands located throughout the study region. Each tree was represented on average by 5 cones, in total 415 cones were analyzed. Morphometric analyses included 16 morphological characters of cones and their scales selected based on our own observations and published data. Multivariate comparison had shown a large overlap between P. obovata and P. fennica, while individuals of P. abies formed a separate and less overlapping cluster. Among the six qualitative (discrete) characters, shape of seed scale and shape of its upper margin have non-overlapping frequency distributions and can separate P. abies and P. obovata. Several new diagnostic characters are proposed: morphology and size of bract scales and ratio of the size of seed scales and bract scales. Phytocenotic analysis showed that different spruce taxa occupy specific habitats, which in their turn connected with the latitudinal gradient: in normally drained habitats, Picea obovata is found mainly in poor shrubby-green-mossy forests, which are typical of the northern and middle parts of the Northern taiga; Picea abies – in richer green-mossy habitats (Vaccinioso-hylocomiosum, Oxalidoso-hylocomiosum, Hylocomiosum), which begin to occur already from the middle part of the Northern taiga. Picea fennica occupies both habitats.

Using the method of electrical explosion of copper and silver wires in an argon atmosphere, Cu–94Ag, Cu–65Ag, and Cu–22Ag bimetallic nanoparticles are manufactured. The resulting nanoparticles are characterized by the methods of transmission electron microscopy and X-ray diffraction analysis. It is shown that irrespective of the component ratio all particles have spherical shapes, with copper and silver uniformly distributed in their volume. The phases identified in the samples correspond to silver- and copper-based solid solutions. The conditions for an ultrasonic dispersion of nanoparticle suspensions are selected. The sedimentation analysis data indicate that the minimal time of ultrasonic treatment at a power of 23 kW is 5min for Cu–65Ag and Cu–22Ag nanoparticles and 2 min for Cu–94Ag nanopowder. The fabricated nanoparticles are used as antibacterial modifiers of PMMA. The Ag–Cu/PMMA composites demonstrate a high antibacterial activity against Escherichia coli.

The search for new more effective nanoparticles based antimicrobial agents has been under way in recent decades. Silver nanoparticles are hydrophobic and have a negative charge. We report on the preparation of Ag–Cu bimetallic nanoparticles with various silver contents synthesized by electric explosion of two twisted wires of the metals in argon atmosphere. The method allows to obtain nanoparticles of a given composition, has high performance and scalability. Nanoparticles were investigated using X-ray diffraction, high-resolution transmission electron microscopy, energy dispersive analysis and microelectrophoresis techniques. We evaluated the antibacterial activity of the nanoparticles against Gram-negative E. coli and Gram-positive methicillin resistance S. aureus MRSA. Our study showed that the synthesized nanoparticles have a positive zeta potential of about 30 mV at pH 7.2 and high antimicrobial activity against the tested bacteria strains, which is close to the activity of silver nanoparticles with a size of 20 nm. The high antimicrobial activity of the nanoparticles is due to the prolonged slow release of silver and copper ions, which makes nanoalloys more effective than Cu and Ag metallic nanoparticles. The synthesized nanoparticles have high antimicrobial activity and demonstrate the potential for their use as promising new generation antibacterial agents effective against resistant microorganisms.

γ-Al2O3 porous nanostructures with different morphologies are prepared from an aluminitride nanopowder (obtained by electric explosion) by treatment with water under various conditions. Depending on the parameters of oxidation, the morphology of the nanostructures includes nanosheets, nanoplates, and nanorods. The structures are characterized via transmission electron microscopy, X-ray diffraction, and thermal nitrogen adsorption–desorption. The adsorption of reference cationic and anionic dyes from aqueous solutions is used as an example to analyze the sorption properties of the nanostructures. It is shown that the Sips model is the one closest to the experimental adsorption isotherm for all γ-Al2O3 samples, regardless of their morphology. It is found that nanorods have the highest adsorption capacity with respect to eosin, while methylene blue is adsorbed similarly by nanorods and nanoplates. It is concluded that the obtained nanostructures can be used as promising materials for water purification, due to the simplicity of their synthesis and their high adsorption characteristics.

Metastatic triple negative breast cancer is considered to be a chemosensitive malignancy especially in treatment-naïve setting. However, tumor cells are able to develop various mechanisms of drug resistance and eventually they become insusceptible for common cytostatic agents. Expansion of treatment-resistant tumor cells represents significant therapeutic challenge and this leads to unfavorable prognosis of advanced triple negative breast cancer. Backbone of treatment for patients with this disease is sequential treatment with various cytostatic drugs with non-cross resistant mechanisms of action, however even with the stateof-art therapy median overall survival does not exceed 15 months. The integration of novel epothilone analogue ixabepilone into clinical practice appears to be a promising strategy for the treatment of advanced pretreated triple-negative breast cancer, especially for patients who are resistant to taxanes and anthracyclines. Combination of ixabepilone with capecitabine is superior to capecitabine monotherapy in terms of response rate (34.7% vs 14.3% with capecitabine monotherapy) and median progressionfree survival (5.8 months vs 4.2 months). At the same time ixabepilone has favorable safety profile and manageable toxicity, 67% developed peripheral neuropathy which is comparable to neuropathy rate with other microtubule inhibitors such as taxanes and eribuline. Here we describe a clinical case of patient with heavily pretreated metastatic triple negative breast cancer resistant to taxanes, anthracyclines and eribuline who was successfully treated with ixabepilone and capecitabine combination.

Electrical explosion of aluminum wires has been shown to be a versatile method for the preparation of bimodal nano/micro powders. The energy input into the wire has been found to determine the relative content of fine and coarse particles in bimodal aluminum powders. The use of aluminum bimodal powders has been shown to be promising for the development of high flowability feedstocks for metal injection molding and material extrusion additive manufacturing.

Background: Flower-shaped micro/nanostructures containing adsorbent and antimicrobial agent within the same particle are a new generation of materials with considerable potential in the field of biomedicine. Objective: Flower-shaped micro/nanostructures were fabricated by the reaction of Al/Cu, Al/Fe and Al/Zn bimetallic nanoparticles with water. Al/Cu, Al/Fe and Al/Zn nanoparticles were produced by the simultaneous electric explosion of a pair of the corresponding metal twisted wires (aluminum and copper, aluminum and iron or aluminum and zinc) in argon atmosphere. The synthesized bimetallic nanoparticles interact with water to form micro/nanostructures with flower-shaped morphology. Methods: The properties of the obtained products were characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, adsorption of nitrogen (BET method) and electrophoretic mobility. The antimicrobial activity of the micro/nanostructures against the bacteria Escherichia coli was studied. The toxicity of these micro/ nanostructures against the L 929 mouse fibroblast cell line was investigated. Results: The micro/nanostructures showed biocidal activity against gram-negative bacteria. The micro/nanostructures AlOOH(Fe) have a low toxicity and can be used for drug delivery. Conclusion: The micro/nanostructures with flower-shaped are good candidates for medical applications as antimicrobial and healing dressing components.

The influence of sintering of an aerogel sample on spectral line parameters of carbon monoxide confined inside aerogel pores is studied for the first time. The measurements were carried out in the 4000–4400 cm–1 spectral range using the Bruker IFS 125HR spectrometer. It is shown that the sintering increased CO halfwidths but did not affect rotational dependences of CO lines.

Therefore, researchers devote special attention to the search of new composite nanoparticles for biomedical applications. In this research CuO–ZnO composite nanoparticles was synthesized by electrical explosion of cooper and zinc wires in oxygen containing atmosphere. The atomic ratio of metals in the nanoparticles was regulated by varying the wire diameters. The as-synthesized nanoparticles were characterized by powder x-ray diffraction analysis, transmission electron microscopy, energy-dispersive x-ray spectroscopy techniques, sedimentation method, micro electrophoresis and adsorption of nitrogen (BET method). The particles are mostly spherical or close to spherical shape. In the x-ray diffraction patterns of the synthesized nanoparticles the main reflexes correspond to the phases of ZnO and CuO. Furthermore, antibacterial activity of ZnO–CuO nanoparticles against Escherchia coli (ATCC 25922) and MRSA (ATCC 43300) were studied, using agar diffusion test and micro dilution assay. Theses result showed synthesized CuO–ZnO nanoparticles have efficient antibacterial activity against gram positive and gram negative bacteria and exceed the antibacterial activity of ZnO and CuO nanoparticles.

77 Ni–23 Ag nanocomposite powder as well as nanopowders of Ni and Ag were produced by electric explosion of wires, and compacted specimens were made with the help of a cold sintering method at a high pressure. It is shown that electric explosion results in formation of mainly janus-nanoparticles of immiscible Ni and Ag metals with retention of nanostructure in consolidated bulk specimens. Microstructure and mechanical properties of cold sintered specimens prepared from as prepared and heat treated in hydrogen flow have been studied. It is ascertained that treatment of 70% dense compacts in hydrogen flow results in higher density and higher ductility of cold sintered specimens. Density of cold sintered at 3 GPa pressure 77 Ni–23 Ag and Ni specimens was reached about 95% from theoretical value whereas the density of Ag specimens is close to 100% of that. High strength was obtained under three-point bending tests and in compression tests.

The present work shows the ability to synthesize bimetal Janus nanoparticles of immiscible iron and lead metals via the electric explosion of two conductors. The electric characteristics of the explosion of Fe and Pb conductors are studied, and the dispersion/phase composition of nanoparticles, as well as the elemental distribution in nanoparticles, is comprehensively analyzed. Finally, the mechanism of the formation of Fe–Pb Janus nanoparticles under the electric explosion of conductors is proposed as well.

We have prepared a composite thin coating by incorporation of CuFe2O4/Cu2O/CuO nanoparticles in polymethyl methacrylate (PMMA) matrix by using the solution casting method. The electrical explosion of two twisted wires (EETW) was used to obtain multicomponent CuFe2O4/Cu2O/CuO nanoparticles with an average particle size of 20–70 nm. The microscopic studies showed that the nanoparticles in the composite coatings are evenly distributed. However, nanoparticles are strongly agglomerated as the powder concentration in the coating increases to 5 wt.% and 10 wt.%, as the size of particle agglomerates increases to 50 and 100 μm, respectively. Therefore, nanoparticles were pre-treated with ultrasound when introduced into the PMMA matrix. The thermal stability of the composite coating does not change with the introduction of CuFe2O4/Cu2O/CuO nanoparticles in the amount of 5 wt.%. The inclusion of nanoparticles in the PMMA matrix significantly enhances its antibacterial activity. The addition of 5 wt.% nanoparticles inhibited the growth of E. coli by 100% and the growth of MRSA by 99.94% compared to pure PMMA already after 3 h of exposure of bacteria on the surface of the composites. This research provides an easy-to-manufacture and cost-efficient method for producing a CuFe2O4/Cu2O/CuO/PMMA composite coating with a broad application as an antibacterial material.

e17551 Background: recurrent ovarian cancer (OC) patients with platinum-free interval (PFI) < 6 mo. are usually considered platinum-resistant and treated with non-platinum chemotherapy. However, this practice is not based on proper-conducted randomized trials. Methods: we queried the PubMed database for all full-text articles and abstracts on the treatment of patients with platinum-resistant ovarian cancer (PROC) in 01/01/2000-01/06/2019 timeframe. The PRISMA tool was used to ensure transparent reporting of the results. Inclusion criteria were: 1) histologically confirmed epithelial OC; 2) recurrent disease within 6 months after completion of platinum chemotherapy; 3) treatment with platinum- or non-platinum chemotherapy agents that are routinely used for OC; 4) no concomitant therapy with targeted or investigational agents; 5) defined response rate (RR) and assessment criteria. Proportion meta-analysis (random-effect model) and beta-regression were conducted to assess the impact of platinum agents on response rate as well as significance of other variables. In the beta-regression model response rate was a dependent variable, while platinum agents (yes or no), used non-platinum drugs and method of response assessment were independent variables. Statistical analysis was dose with meta and betareg packages of R software. Results: we identified 7156 articles and screened them for title and abstract, 157 studies for further analysis. Efficacy of non-platinum- and platinum-based therapy was assessed in 113 (n = 5272) and 44 (n = 1055) trials respectively. In meta-proportion random-effect model RR among patients treated with platinum-based and non-platinum chemotherapy RR was 36% (95% CI 30-41; I2 = 62%) and 16% (95% CI 14-19; I2= 70%) respectively. Multiple beta-regression model is presented in the Table below. For sensitivity analysis various regression models were made with different subsets of the trials and additional variables (including year of the trial, percentage of serous subtype of OC and median of prior therapy lines). Platinum was the strongest predictor of response in every developed model. Conclusions: this meta-analysis shows that patients with 'platinum-resistant' ovarian carcinoma may derive significant benefit from reintroduction of platinum agents. These results support recent ESMO-ESGO consensus on treatment of recurrent ovarian cancer and randomize trials are required to refine the role of platinum in early relapsed OC.[Table: see text]

Porous composites of different phase composition are synthesized via oxidation in a water–ethanol mixture of bimetallic Al/Zn nanoparticles obtained through a joint electrical explosion of aluminum and zinc wires in an argon atmosphere. It is found that the oxidation of aluminum and the formation of boehmite nanosheets proceed in solutions containing 7‒20 wt % of water. At water contents over 20 wt %, the almost complete oxidation of aluminum is followed by the onset of zinc oxidation, resulting in the formation of composites containing boehmite nanosheets and hexagonal plates enriched with zinc oxide. Composites synthesized in this way display high antimicrobial activity against bacteria, due mainly to the release of Zn2+ ions into the solution. The greatest antimicrobial activity is observed in composites that simultaneously contain AlOOH, Al, ZnO, and Zn phases. The strong migration of Zn2+ ion is due to the structure of these composites, in which the active zinc surface grows as a result of the availability of ZnO plates located between the boehmite nanosheets. The boehmite nanosheets ensure stability of the composite structure and electrostatic interaction with bacteria.

In the work, the samples obtained from polymeric feedstock based on bimodal powders of Cronix 70 alloy, obtained by an electric explosion of wire, are investigated. Samples were obtained by the 3D-FDM printing method with the use of micro-extrusion head for a 3D printer. It was found that the density of printed products is at least 95% when sintering parts to 0.9 from the melting point. Despite the discreteness of the obtained parts, the tensile strength and hardness are within the range of standard values for the Cronix 70 alloy.

Titanium alloys are in demand in engineering and medicine due to high specific strength, high corrosion resistance and biocompatibility. Powder injection molding is the most suitable method for producing small batches of complex shaped items. Titanium alloy bimodal powders obtained by electric explosion of wires are promising materials for PIM. The EEW conditions to prepare Ti-6Al-4V alloy bimodal powders with a uniform distribution of nano- and micro- particles have been determined. The load of bimodal powder in feedstock was 93 wt %. The density of the sintered samples reached 98% TD, and the microhardness was 3.1±0.3 GPa. The elemental composition of the sintered samples was close to that of the original wire.

In the present study, bimodal tungsten carbide WC powders are successfully prepared by a two-stage process: electrical explosion of wire (EEW) synthesis of bimodal tungsten powder followed by a carburization reaction. The conditions of the EEW synthesis have been determined, resulting in the preparation of the bimodal powder. During the carburization process, the tungsten carbide WC is formed through the transition phase W2C. The carbon content in the obtained WC powders is very close to the theoretical value. Also, it was found that a high C/W molar ratio at the carburization stage does not affect the carburization process significantly. Optimal conditions for the tungsten carbide WC synthesis have been determined: calcination at 1200 °C with 8 h dwell and C/W molar ratio to be 1.4. The yield of tungsten carbide is 99 wt% under these conditions. Thus, the carburization process of bimodal tungsten powder may provide a low-cost and high-efficiency route to prepare the WC powders for various applications.

A simple and environmentally friendly method to prepare aluminum oxyhydroxide and trihydroxide nanostructures by wet oxidation of AlN/Al composite nanoparticles was developed. The AlN/Al nanoparticles used were produced by electrical explosion of an aluminum wire in nitrogen atmosphere. The obtained nanostructures were characterized employing X-ray diffraction (XRD), transmission and high-resolution scanning electron microscopy (TEM and HRSEM), thermogravimetric analysis (TGA) and N2 adsorption-desorption technique (BET). By changing the wet oxidation conditions, aluminum hydroxides with different phase composition, morphology and texture characteristics were synthesized. After calcination at different temperatures, a range of transition and stable alumina nanostructures were obtained that preserved the morphology of the aluminum hydroxide precursors - agglomerated nanosheets, nanoplates or hexagonal nanorods, up to 1000 °C. Optimal process parameters for maximum surface area development for all the precursor materials have been established.

Background Recent advances in nanotechnology make it possible to create nanomaterials with novel microstructure and unique physicochemical properties. Different structures of nanoparticles of immiscible elements can be synthesized using chemical, mechanochemical or physical methods. The present review is devoted to contemporary state of the studies on the methods to produce bimetallic nanoparticles formed of immiscible metals. Methods We undertook a structured search of bibliographic databases for peer-reviewed research literature using a focused review question and inclusion/exclusion criteria. The quality of retrieved papers was appraised using standard tools. Results Ninety-six papers were included in the review. Taking into account a large number of works in this field of the studies in the present review we are going to consider general methods of producing BMINPs with diverse structures: core-shell (twenty one papers), nanoalloys (twenty papers), Januslike (sixteen papers). The field of BMINPs application was described in seventeen articles. In the part Current & Future Developments the perspectives on the usage of bulk materials produced by BMINPs consolidation are discussed. Conclusion As can be seen from this review, ideal bimetallic nanoparticles synthesis methods are not developed by now. The existence of different routes to nanoparticles synthesis and their unique properties confirm the importance promoted awareness of potential benefits of nanoparticles in different applications. The reviewed patents emphasized the importance of bimetallic nanoparticles and their application in various fields as well.

The near infrared transmission spectra of nanoporous SiO2/Al2O3 xerogel have been recorded for the first time in the process of filling of nanopores with ammonia and acetone molecules. It has been found that the physical adsorption of these gases results in a reversible increase in the translucence of xerogel samples at the frequencies of vibrational bands of surface OH groups.

In this work, in situ method of producing hybrid fibrous adsorbents in which boehmite nanosheets with high sorption properties formed on the surface of hydrophilic microfibres, such as cellulose acetate and glass fibre, was described. The boehmite nanosheets were fabricated by the reaction of composite AlN/Al nanoparticles with water at 60 °C. The synthesized samples were characterized by X-ray diffractometer, scanning, transmission electron microscopy, Fourier transform infrared spectrometer (FT-IR), zeta-potential and specific surface area analyzers. The introduction of microfibres into a diluted aqueous suspension of nanopowders causes heteroadagulation of the nanoparticles and accelerates their further transformation. This effect is most substantial with the glass microfibre, which is thought to have a higher concentration of surface groups capable of generating hydrogen bonds that act as heteroadagulation and nucleation centres. The experimental results showed that the morphology of the resultant hybrid fibrous adsorbents differed accordingly: the nanosheets were attached on-edge to the glass microfibre surface, while on the surface of the cellulose acetate microfibre, they were secured in the form of spherical “nanoflowers” of agglomerated nanosheets. The effect of the morphology of hybrid fibrous adsorbents on adsorption bacteria Escherichia coli was also investigated.

Recent advances in nanotechnology make it possible to create nanomaterials based on γ-alumina with novel hierarchical structure and physicochemical properties. Hierarchical γ-alumina can be synthesized using chemical or physical methods. The nanostructures based on γ-alumina exhibit unique properties, which are utilized in the design of efficient applications. These superior properties are often due to their hierarchical organizations from the nanosize scale to the macroscopic level. The present review is devoted to the contemporary state of the studies on the methods to produce hierarchical γ-alumina. We tried to summarize herein the literature data on the methods of synthesis of hierarchical γ-AlOOH and γ-Al2O3 with controlled morphology and the application of these methods for the synthesis of hierarchical γ-AlOOH and γ-Al2O3 nanocomposites.

Metal powder composites for powder injection molding (PIM) technology have been studied. Stainless steel 316L bimodal powders consisting of both nano and microparticles and multicomponent binders based on PLA/PMMA (feedstock I), paraffin wax/PE-LD/PMMA (feedstock II) and polyethylene wax (feedstock III) were used to obtain feedstock. The effect of the binder composition on the characteristics of feedstocks and sintered compacts was investigated. The use of PMMA in a binder allows maintaining the strength of the compacts to high temperatures when sintering. The debinding of “green compacts” from feedstock III leads to an almost complete removal of paraffin wax, and the “brown” parts retain their shape only due to the low-temperature sintering of nanoparticles. The use of the paraffin wax as a binder requires an increase in the content of the bimodal metal powder in the feedstock to 95 wt% to increase the strength of the compacts. Feedstocks and molded compacts were characterized by TEM, SEM, DSC-TG methods.

Metal powder composites for Powder injection molding (PIM) technology have been investigated. 316L stainless steel bimodal powder, obtained by electric explosion of the wire and multicomponent binder comprising PMMA, PE-LD and Viscowax were used to obtain feedstocks. The effect of PMMA content in the binder on the properties of feedstocks and sintered parts has been studied. As the PMMA content increases, the molding temperature of the parts rises from 140 to 200°C, the strength of the “green” and “brow” parts increases as well. The optimal PMMA content in the binder has been found to be 15–20 vol %. “Brown” samples sintered in vacuum at 1300°C exhibit shrinkage up to 23% and the samples density reaches 0.98 TD. Samples of feedstocks were characterized by TEM, SEM, DSC-TG methods.

e24096 Background: Immune checkpoint inhibitors can sometimes lead to fatal outcomes or significant morbidity due to immune-related adverse events (IRAE). Cardiac IRAE, especially myocarditis, are among the most fatal IRAE. There are scarce of the trials addressing the optimal therapeutic approaches for patients with IR-myocarditis. Initial therapy with high-dose steroids (1000 mg of prednisolone for 3-5 days) may be beneficial for many patients with this IRAE and this approach is endorsed by NCCN guidelines. We conducted a systematic review with individual patient-level data meta-analysis of published clinical cases to assess impact of various initial therapeutic modalities and adherence to NCCN guidelines on outcomes of immune-related myocarditis, associated with checkpoint inhibitors. Methods: We searched PubMed database for all full-text articles and abstracts on the treatment of patients with cardiac-related IRAE treated with various PD-1/PD-L1 or CTLA-4 inhibitors for years between 2012 and 2020 in English. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) tool was used to ensure transparent reporting. Main study inclusion criteria were: 1) morphologically confirmed immune-related myocarditis or highly clinically suspected autoimmune myocarditis (based on Bonaca et al, 2019 criteria); 2) clear association of IRAE and administration of check-point inhibitors; 3) availability of individual patient and treatment data. Pooled analysis of outcomes and multiple logistic regression analysis were conducted. The primary outcome of this study was rate of major cardiac adverse events (MACE) due to immune-related autoimmune myocarditis according to adherence to NCCN guidelines. MACE was defined as death or persisting significant disabilities due to myocarditis (ie, chronic heart failure, rhythm abnormalities or deterioration leading to impossibility of further anticancer treatment). Results: We identified 277 articles and screened them for title and abstract. After the review process we selected 81 studies for further analysis which described treatment course for 111 patients. Overall, 26 and 85 patients were treated with high-dose and non-high dose steroids. Among patients treated high-dose steroids therapy and non-high dose steroids 10 (38.5%) and 57 (67.1%) of patients respectively experienced MACE (HR 0.185; 95% CI 0.07-0.47; p = 0.0091). Initial treatment failure was associated with high rate of morbidity; however, 9 patients were rescued with various immunosuppressive drugs (eg, tacrolimus, alemtuzumab, tocilizumab). Conclusions: Our results support use of high-dose pulse therapy as a preferred therapeutic approach for all patients with suspected or proven immune-related myocarditis.

Transformation of C2H4, CO2 and C2H6 absorption spectra confined in nanopores of SiO2/Al2O3 aerogel is studied for the first time in comparison with the spectra of these molecules in the free state. It is shown that the integral intensities of confined C2H4 within 5700–6250 cm–1, CO2 within 4760–5160 cm–1, and C2H6 within 2830–3030 cm–1 are higher by 13.3, 15, and 18 times, respectively, than those of free gases.

Novel 3D AlOOH/Fe micro/nanostructures were successfully synthesized by the reaction of Al/Fe binary metallic nanoparticles with water at 60°C and under atmospheric pressure. Al/Fe binary metallic nanopowder was produced by the method of simultaneous electric explosion of twisted aluminum and iron wires in an argon atmosphere. Produced 3D AlOOH/Fe structures were characterized by TEM, SEM, XRD, EDX, BET, and adsorption capacity towards As (V). The hard framework consisting of both the boehmite nanosheets and the nanosheets enriched with iron provides a large available surface and prevents the aggregation of the micro/nanostructures. The high adsorption capacity of 42 mg g-1 As (V) under static conditions allows obtained 3D AlOOH/Fe micro/nanostructures to be a promising material for the removal of arsenic from contaminated drinking water.

During the electrical explosion of aluminum wires in argon and nitrogen, Al nanoparticles and Al/AlN composite nanoparticles were synthesized. The as-prepared samples were characterized by transmission electron microscopy, energy dispersive X-ray microanalysis, X-ray diffraction and Brunauer–Emmett–Teller specific surface area measurements. The parameters of the electrical explosion of wires and the gas medium influenced the average size of the nanoparticles and the content of aluminum nitride in the powder. A nanoparticle formation mechanism caused by the coagulation of the primary particles generated in the early stages of the electrical explosion of the wires has been proposed.

In this study, Cu/Ag, Сu/Pb and Al/Pb binary metallic nanoparticles were synthesized by the electrical explosion of two twisted wires from immiscible elements (i.e., Сu–Ag, Cu–Pb and Al–Pb). The distribution of metallic components in the nanoparticles depended on the melting temperature, metal density, and degree of initial wire superheating. Different types of nanoparticles, such as nanoparticles with no separation between the metal phases, as well as core-shell and Janus nanoparticles were formed depending on the process parameters and the characteristics of the metals. Certain binary metallic nanoparticles were formed when the metal clusters were combined and formed during the initial stages of dispersing the two wires using a pulse of electrical current.

e18076 Background: Current management of recurrent ovarian cancer (OC) is based on the amount of time between the completion of penultimate platinum-based treatment and the detection of relapse. Patients with platinum-free interval (PFI) < 6 mo. are considered to be platinum-resistant (PROC) and to have low response rate (RR) probability to platinum-based chemotherapy. Methods: We searched PubMed database for all prospective and retrospective full-text articles and abstracts on the treatment of patients with PROC for all years between 01/01/2000 and 01/06/2019 in English language. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) tool was used to ensure transparent reporting of the results. Study inclusion criteria were: 1) morphologically confirmed epithelial ovarian cancer; 2) standard definition of PROC as a disease that recurred within 6 months after completion of platinum-based chemotherapy; 3) treatment with platinum- or non-platinum chemotherapy with agents that are routinely used for OC; 4) no concomitant therapy with targeted or investigational agents; 5) clearly defined RR for patients with PROC and criteria used for response assessment. Pooled analysis of outcomes and multiple linear regression analysis was conducted to assess the impact of platinum salts on probability of response. Results: We identified 7156 articles and screened them for title and abstract. After the review process we selected 197 studies for further analysis. Of them, 52 (n = 1320) and 145 (n = 6937) trials assessed efficacy of platinum- and non-platinum based chemotherapy respectively. Among patients treated with platinum-based and non-platinum chemotherapy RR was 36.04% (95% CI 33.45-38.63) and 14.85% (95% CI 14.01-15.68) respectively. Pooled median progression-free survival was 5.8 mo. and 3.75 mo. respectively. In multiple linear regression model administration of platinum-based chemotherapy was the strongest predictor of objective response with B value 0.503 (p < 0.001). Among platinum agents cisplatin (RR 39.9%: 95% CI 35.8-44.0%) and carboplatin (RR 42.3%; 95% CI 37.0-47.6%) were associated with better rates of objective response compared to oxaliplatin (RR 28.1%; 95% CI 23.9-32.3). Conclusions: This systematic review shows that patients with 'platinum-resistant' ovarian carcinoma may derive significant benefit from reintroduction of platinum agents and their value should be evaluated in further randomized trials.

1079 Background: patients with triple negative breast cancer has poor survival outcomes. Achievement of pathological complete response (pCR) after neoadjuvant chemotherapy can significantly improve survival of these patients, however some patients will relapse even after pCR. Methods: we reviewed prospectively-maintained outcomes database of N.N. Blokhin NMRCO. We extracted information about patients with locally advanced non-metastatic (stage IIIA-IIIC) triple negative breast cancer who were treated with neoadjuvant platinum based chemotherapy in 2014-2018 years. All included patients were tested for the presence of BRCA1/2 mutation with whole-exome next-generation sequencing or for “founder” hot-spot mutations. Results: we identified 80 patients who received neoadjuvant treatment with various platinum-based regimens. Pathological complete response rate was 62.5%. BRCA-mutations was found at 22 (27.5%) patients. Median follow-up time was 35.6 months (17.0 – 61.3). 2-year DFS was 77.3%, and 3-year DFS was 70.0%, there was significant differences in DFS in patients, who achieved and patients with residual tumor – 85,2% vs 64,3% (p=0,028). 2-year OS was 91%, 3-year OS was 78,5%. 18 patient had disease progression, the most common sites of disease progression were brain (9 [50.0%]), lungs (5 [27.8%]), 3 (16.7%) patients had locoregional relapses and 1 (5,6%) liver metastases. We separately analysed characteristics of patients with brain metastases (table). There were no significant differences in tumour pathologic response and patient age. All patients, who relapced after pCR, had brain metastases. We also found, that 7 of 9 patients with brain metastases had different BRCA mutations. Brain metastases developed in 40,9% (9/22) of patients with BRCA1 mutations and 3,4% (2/58) of patients with wild type BRCA1 (p

The protected area Kurgalsky is situated on the south-western coast of the Gulf of Finland near the Estonian border and has the status of a regional nature reserve ("zakaznik"). It comprises a marine area with a number of small islets. The Kurgalsky Nature Reserve is included in the network of Helcom Baltic Sea Marine Protected Areas and Wetlands of International Importance (Ramsar Sites). This area is a refuge for a great number of rare and threatened species and plant communities of high conservation value. Based on the research carried out by the authors in the 2000s in the Kurgalsky Reserve and analysis of all previously published information on vascular plants, bryophytes and lichens, as well as vegetation of the area, the most valuable botanical objects were identified. New data on the locations of many rare and protected species were obtained. Six species of mosses (Atrichum flavisetum, Aulacomnium androgynum, Racomitrium lanuginosum, Sphagnum aongstroemii, S. palustre, Ulota intermedia) and 9 lichen species (Alectoria sarmentosa subsp. sarmentosa, Evernia divaricata, Menegazzia ter-ebrata, Nephroma bellum, Parmeliella triptophylla, Ramalina baltica, Scytinium subtile, Xanthoparmelia loxodes, X. pulla) listed in the Red Data Book of the Leningrad Region were found in the Reserve in the 2000s for the first time, including the nationally red-listed Aulacomnium androgynum and Menegazzia terebrata. Moreover, new locations of 17 protected species of vascular plants, 3 liverwort species and 2 lichen species were discovered. An annotated list with new locations of rare and protected species is represented. The total number of red-listed species of vascular plants, bryophytes and lichens in the Kurgalsky Reserve is 78 (50 vascular plant species, 11 bryophytes and 11 lichen species), including 11 vascular plant species, 1 moss species and 2 lichen species listed in the Red Data Book of the Russian Federation. Besides, 2 vascular plant species, 5 bryophytes and 19 lichen species are proposed to be included in the Red Data Book of the Leningrad Region. Maps of the distribution of protected species of vascular plants, bryophytes and lichens known from the Reserve are published for the first time. The spatial distribution of red-listed species was analyzed. Despite the fact that each of the considered groups (vascular plants, bryophytes and lichens) has its own biological and ecological features that determine their distribution within the area, it is possible to distinguish some general patterns in the spatial distribution of the species. Thus, the largest number of rare and threatened species, habitat specialists and indicator species of vascular plants, bryophytes and lichens are clearly associated with rare or unique landscapes in the Kurgalsky Reserve. An important feature of the distribution of bryo-phytes and lichens is their specific relationship with the long-term characteristics of substrates and microclimatic features of habitats. The Kurgalsky Nature Reserve is definitely one of the most valuable, biologically diverse and rich protected areas of the Leningrad Region, and it is extremely important to safeguard this unique area.

X-ray phase analysis, transmission electron microscopy, and X-ray microanalysis were used to examine the structural-phase states of Fe–Cu and Fe–Ag bimetallic nanoparticles. The nanoparticles were obtained by the electric explosion of two twisted metal wires in argon atmosphere. It was demonstrated that the nanoparticles have the structure of Janus particles. Presence of the Janus particle structure in the samples indicates formation of binary melt under conditions of combined electric explosion of two wires. Phases based on supersaturated solid solutions were not found in the examined samples. The data obtained allow arguing that it is possible to achieve uniform mixing of the two-wire explosion products under the described experiment conditions.