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Aim To study intracardiac hemodynamics in healthy men in supine and prone positions.Material and methods This echocardiography study included 14 apparently healthy men at a mean age of 38 years.Results In a prone position, the heart configuration and location in the chest changed, the heart rate increased by 7.3 %, and the transaortic flow velocity decreased by 13.7 %. Also, early and late right ventricular diastolic filling velocities and the pulmonary artery flow velocity were increased by 31.7, 11.4, and 5.6 %, respectively. In the intact tricuspid valve, the velocity and regurgitation pressure gradient were reduced by 7 % and 14.2 %, respectively.Conclusion In a prone position, spatial changes in the location of the heart and its structures influence velocities of intracardiac blood flow, which may initiate the development of heart failure if the prone position is long-lasting.

Background. The mitochondrial electron transport chain, in particular the respiratory complex I, is one of the main sources of reactive oxygen species (ROS) in living cells. Suppression of the complex I activity in human cells through chemical inhibition or mutations that disrupt the functionality of this complex leads to a significant increase in the content of ROS. The complex I mutants are also known for plants; however, it is still not clear whether the suppression of the activity of this complex leads to an increase in the level of ROS and the development of oxidative stress. Purpose. To study the level of superoxide, hydrogen peroxide and sensitivity to prooxidants in Arabidopsis ndufs4 cells with complex I inactivated by insertional mutagenesis. Materials and methods. A suspension culture of wild-type Arabidopsis cells and a line with knockout the NDUFS4 complex I subunit was used. The level of hydrogen peroxide in the cells was determined using dichlorofluorescein. The superoxide content was estimated by cell staining in the presence of nitroblue tetrazolium. Results. It has been shown that inactivation of the NADH-dehydrogenase complex in Arabidopsis cells due to the absence of one of its subunits leads to a decrease in the content of superoxide and hydrogen peroxide. It was also shown that the level of ROS in cells treated with the menadione and hydrogen peroxide increased several times in wild-type cells, but remained almost unchanged in ndufs4 cells. Conclusion. Suppression of the activity of the NADH dehydrogenase complex in plant cells, but not in animal cells, leads to a decrease in the content of both hydrogen peroxide and superoxide. Cells of ndufs4 line have an increased ability to detoxify ROS, possibly associated with the constant mobilization of antioxidant defense systems.

INTRODUCTION. The leading role in the water and electrolyte balance in critical conditions belongs to infusion therapy. Hemodynamic stabilization is achieved by fluid bolus with risk of hypervolemia. Non-invasive monitoring in ICU is relevant in children. Cardiointervalography is characterized by nosological non-specificity and high sensitivity to neurohumoral changes. The stress index and spectral analysis allow the assessment of therapeutic efficacy. OBJECTIVES. To study the features of the electrophysiological response to the emergency rehydrate volume in children upon admission to the intensive care unit. MATERIALS AND METHODS. A prospective comparative study was conducted with the participation of 172 patients, the age from 0 to 15 years. There were 71 newborns in the first group (21 surgical cases, 50 somatic ones). The second group enrolled children aged 1 to 15 years, in 40 % of all underwent surgical treatment. The characteristic of the electrophysiological response to the hydration was carried out in an intergroup and interstage comparison in different age and nosological groups. DISCUSSION. The autonomic nervous system response to infusion therapy has not been studied in children of different ages. The stress index and frequency analysis reflect the degree of regulatory systems tension and are promising in intensive care monitoring. RESULTS. In newborns with sensory block, it was expressed by tachycardia (p = 0.02); without block — arterial hypotension (p = 0.000) without chronotropic component. The implementation of sympathetic reactions was suppressed in children in the early postoperative period. In children without surgical treatment, the volume of infusion had a sympatholytic effect. CONCLUSIONS. In the early postoperative period, the electrophysiological response in children was limited. Age-related features of reactions to hydration in children with somatic pathology were revealed. In children, infusion therapy contributed to a cardiovascular economical work; in newborns, it was associated with a breakdown in sympathetic adaptation.

At the Institute of Nuclear Physics, a nine-pole hybrid wiggler is developed and successfully installed on the VEPP-4 accelerator complex. The nine poles of the wiggler are electromagnets with iron cores. To achieve the largest field, permanent magnets with a residual induction of 1.2 T are installed between the wiggler poles. Such a combination of electromagnets and permanent magnets made it possible to achieve a maximum magnetic induction of 1.9 T, with an interpolar gap of 30 mm. Currently, at the Siberian Center of Synchrotron and Terahertz Radiation, several research methods using the “hard” X-ray range (50–250 keV) based on radiation from a nine-pole wiggler are being certified. For example, using this radiation, the X‑ray imaging of fast processes, X-ray computed tomography, X-ray fluorescence analysis, and X-ray diffraction studies are carried out. A brief review of these studies is presented.

Clonal propagation of conifers using somatic embryogenesis is essential for the selection of tree species, and for the implementation of afforestation and reforestation. In combination with cryopreservation, somatic embryogenesis creates the basis for the development of economically valuable lines of clones and elite genotypes. The industrial use of such genetically verified clone lines in forestry can significantly increase forest productivity compared to any conventional methods for improving tree crops that are available. Larch is considered as one of the main conifer candidates for large-scale reforestation, not only due to the vastness of its habitat, but also due to the unique quality of its wood, rapid growth and high ecological plasticity. However, the vast majority of larch species are characterized by uneven yields and extremely low seed quality. In this regard, obtaining planting material for reforestation from larch seeds on seed plantations is not advisable, but can be successfully implemented in afforestation programs using somatic embryogenesis technologies. Research on the somatic embryogenesis of larch has been conducted for over 30 years, which allowed considerable experience in this field to be accumulated. To date, the conditions for the initiation and maintenance of embryogenic cultures, as well as for the formation and development of somatic embryos have been determined. Significant progress has been made in the study of both the factors affecting these processes and the molecular mechanisms that underlie the various stages of embryogenesis. Nevertheless, despite the successes achieved, knowledge available today on the somatic embryogenesis of representatives of the genus Larix is still not enough to develop technologies for producing valuable plant-breeding material in vitro. This review analyzes the current state of research on the problem of somatic embryogenesis of representatives of the genus Larix. Particular attention is paid to the choice of explants for somatic embryogenesis, the composition of the media for cultivation, the dependence of the potential of somatic embryogenesis on the duration of cultivation, and the genetic control of somatic embryogenesis.Клональное размножение хвойных с использованием соматического эмбриогенеза имеет суще- ственное значение для селекции древесных видов, реализации программ лесоразведения и лесовосстановле- ния. В сочетании с криоконсервацией соматический эмбриогенез создает основу для получения хозяйственно ценных линий клонов и элитных генотипов. Использование в промышленных масштабах в лесном хозяйстве та- ких генетически проверенных линий клонов может значительно увеличить продуктивность лесов по сравнению с любыми доступными традиционными методами улучшения древесных культур. Лиственница считается одним из основных кандидатов для широкомасштабного лесовосстановления не только за счет обширности занима- емых ареалов, но и благодаря уникальному качеству ее древесины, быстрому росту и высокой экологической пластичности. Однако большинство видов лиственницы характеризуется неравномерностью урожаев и чрез- вычайно низким качеством семян. В связи с этим получение посадочного материала для лесовосстановления из семян лиственниц на семенных плантациях нецелесообразно, но может быть успешно реализовано в програм- мах по лесоразведению с применением технологий соматического эмбриогенеза. Исследования по соматиче- скому эмбриогенезу лиственницы проводятся уже более тридцати лет, что позволило накопить значительный опыт в данной области. К настоящему времени изучены условия инициации и поддержания эмбриогенных культур, формирования и развития соматических зародышей. Достигнут значительный прогресс в изучении как факторов, влияющих на эти процессы, так и молекулярных механизмов, лежащих в основе различных этапов эмбриогенеза. Однако имеющихся на сегодняшний день знаний о соматическом эмбриогенезе пред- ставителей рода Larix все еще недостаточно для разработки технологий получения селекционно-ценного растительного материала in vitro. В обзоре проведен анализ современного состояния исследований по про- блеме соматического эмбриогенеза представителей рода Larix. Особое внимание уделено вопросам выбора эксплантов для соматического эмбриогенеза, составу сред для культивирования, зависимости потенциала со- матического эмбриогенеза от продолжительности культивирования, генетическому контролю соматического эмбриогенеза.

Composition of phospholipids was examined in embryogenic and non-embryogenic cell lines of Siberian larch (Larix sibirica Ledeb.). Significant differences in the content and composition of phospholipids were revealed between the cell lines. Phosphatidylcholines (PC) and phosphatidylethanolamines (PE) were predominant phospholipids in embryogenic cell lines, whereas non-embryogenic cell lines featured a high content of phosphatidic acid (>64% of total phospholipids). The PC/PE ratio known to characterize the membrane structure and function was 1.4–3.8 times higher for embryogenic cell lines than for non-embryogenic lines; this was probably caused by the involvement of these phospholipids in tissue differentiation. The content of phosphatidylinositols differed significantly for embryogenic and non-embryogenic cell lines, where it equaled to 0.50–1.06 and 0.17–0.34 mg/g dry wt, respectively. The observed variations in the composition of phospholipids between the cell lines with different embryogenic potential provide evidence for the important role of these lipids in embryogenesis at the stage of embryo formation.

Aspirated lipoid pneumonia is a rare lung disease, in which interstitial lesion with chronic respiratory failure is predominantly expressed. In the available literature, this pathology is described in the form of separate observations with an empirical selection of therapeutic measures. The appearance of lipophages in a bronchial aspirate is recognized as a pathognomonic sign of lipoid pneumonia. There is no etiological treatment of the disease. The effectiveness of intensive therapy, according to available sources, depends on the severity of respiratory failure and on the timing of the start of complex bronchodrainage therapy, and theoretically the most attractive is kinesitherapy. Only one observation describes the use of bronchial lavage with sequential separate intubation of the main bronchi. Hormone therapy is considered effective, but the physiological basis for its use is not presented. The published observation is characterized by a late start of treatment due to a long diagnostic search. The applied therapeutic measures are given and described in detail with an assessment of the expected and achieved practical benefits. It was shown that beneficial effects were due to the use of bronchodrainage therapy techniques, including the jet high-frequency artificial ventilation of the lungs. There are doubts about the appropriateness of the use of corticosteroids in this pathology.

Funding Information: The authors thank Mr. Andrei Starkov for illustrations and Mrs. Anastasiya Grebenko for assistance with sample synthesis. This work was performed using equipment of MIPT Shared Facilities Center. The authors acknowledge Vadim Khrapai and Evgeny Tikhonov (ISSP) for assistance with low temperature measurements and professor Galina Tsirlina (MSU) for fruitful discussions. The authors are also grateful to Salavat Khasanov for assistance and verification of XRD measurements. The authors thank the Helmholtz‐Zentrum Berlin für Materialien und Energie for the allocation of synchrotron radiation beamtime. Computations were done at the Finnish IT Center for Science, CSC. Russian Foundation for Basic Research grant # 19‐32‐90143 (A.K.G., A.G.N.). German Federal Ministry of Education and Research (BMBF) grant no. 05K19KER (A.A.M.). Russian Science Foundation No. 21‐19‐00226 (D.V.K., graphene synthesis). Russian Science Foundation No. 21‐72‐20050 (B.P.G., THz‐FIR spectroscopy). Ministry of Science and Higher Education of the Russian Federation within the governmental order for Boreskov Institute of Catalysis project АААА‐А21‐121011390011‐4 (A.N.S.). Partially supported by the Ministry of Science and Higher Education of the Russian Federation No. FSMG‐2021‐0005 (V.S.V., ARPES studies) and Russian Science Foundation No. 21‐72‐30026 (V.S.V, STM Studies). The work was supported by the Council on grants of the President of the Russian Federation grant number НШ‐1330.2022.1.3. Publisher Copyright: © 2022 The Authors. Advanced Science published by Wiley-VCH GmbH Following the game-changing high-pressure CO (HiPco) process that established the first facile route toward large-scale production of single-walled carbon nanotubes, CO synthesis of cm-sized graphene crystals of ultra-high purity grown during tens of minutes is proposed. The Boudouard reaction serves for the first time to produce individual monolayer structures on the surface of a metal catalyst, thereby providing a chemical vapor deposition technique free from molecular and atomic hydrogen as well as vacuum conditions. This approach facilitates inhibition of the graphene nucleation from the CO/CO2 mixture and maintains a high growth rate of graphene seeds reaching large-scale monocrystals. Unique features of the Boudouard reaction coupled with CO-driven catalyst engineering ensure not only suppression of the second layer growth but also provide a simple and reliable technique for surface cleaning. Aside from being a novel carbon source, carbon monoxide ensures peculiar modification of catalyst and in generalopens avenues for breakthrough graphene-catalyst composite production.

The paper presents the study results of CrN/TiN multi-layer coatings, as well as single-layer TiN and CrN coatings on Cr12MoV cold work die steel deposited by the vacuum-arc plasma-assisted method. Three CrN/TiN coatings of 8-, 16-, and 32-layers were deposited, in which the thickness of each layer was 500 nm, 250 nm and 125 nm, respectively. All of the coatings reveal a face-centered cubic structure with highly oriented (111) growth. The hardness of the CrN/TiN multi-layer coatings was about 27 GPa. Changing the architecture of CrN/TiN multi-layer coatings by reducing the thickness of the CrN and TiN layers from 500 nm to 125 nm promotes a smooth decrease in both the wear parameter and the coefficient of friction. By using an X-ray phase analysis with synchrotron radiation, it was found that 32-layer CrN/TiN coating retained thermal stability during heating in air to a temperature of 1120–1125 °C, and in a vacuum at least to a temperature of 1200 °C.

We studied the combined effect of hypokinesia and external cooling on structural and morphological changes in the ventricular myocardium and parameters of homeostasis of the blood system in male and female WKY (normotensive) and SHR (hypertensive) rats. Simultaneous exposure to hypokinesia and cold caused destructive processes in the myocardium and high dynamics of heart remodeling with diverse structural and morphological changes in the left ventricle in rats of both sexes. The thickness of the left ventricular wall most rapidly decreased in male hypertensive SHR rats. The thickness of the wall of the right ventricle significantly increased in male and female rats of both strains. In WKY and SHR females, structural transformations in the heart were less pronounced than in males. The key role in different degree of morphological remodeling of the myocardium in male and female probably belongs to sex hormones.

Electron transfer chains of plant organelles (both chloroplasts and mitochondria) contain their own special set of ferredoxins. The relatively recently described adrenodoxin-like [2Fe-2S]-ferredoxins MFDX1 and MFDX2 of plant mitochondria are among the least studied of these. Until now, the only established function for them is participation in the final stage of biotin biosynthesis. In this work, using genetic and biochemical approaches, we searched for possible partners of these proteins in the genomes and proteomes of tobacco (Nicotiana tabacum L.) and foxglove (Digitalis purpurea L.) plants. MORF9 protein, one of the auxiliary components of the RNA editing complex of organelles (editosome), was found among the most prominent protein partners of adrenodoxin-like [2Fe-2S] tobacco ferredoxins. According to the results obtained from the yeast two-hybrid system, NtMFDX1 and NtMFDX2 of tobacco also bind and interact productively with the previously uncharacterised long non-coding polyadenylated RNA, which, based on its structural features, is capable of regulating the function of a number of components of complexes I (Nad1, Nad5) and III (protein of the cytochrome c synthesis system CcmF) and contributes to the formation of Fe/S-clusters in the corresponding protein complexes of the respiratory chain of plant mitochondria. We found one of the main components of the thiazol synthase complex (mitochondrial protein DpTHI1) to be the partner of ferredoxin DpMFDX2 of Digitalis purpurea. Finally, additional arguments were obtained in favour of the possible participation of MFDX1 and MFDX2 in the very ancient, but only recently described ‘progesterone’ steroid hormonal regulatory system: in leaves of the previously constructed CYP11A1-transgenic tomato plants, only the mature form of mitochondrial cytochrome P450scc (CYP11A1) of mammals is able to enter the mitochondria, where the above-mentioned components of the electron transport chain are localised. In summary, all of the newly revealed interactions of adrenodoxin-like [2Fe-2S] ferredoxins MFDX1 and MFDX2 indicate their participation in a wide range of functions in plant mitochondria.

«Genome uncoupled» (gun) is a molecular phenotype manifesting in a high expression of a number of nuclear photosynthesis associated genes in plants with arrested chloroplast biogenesis. The chloroplast biogenesis arrest could be achieved by growing of plants in presence of lincomycin (plastid translation inhibitor) or norflurazon (carotenoid biosynthesis inhibitor). We have found that Arabidopsis thaliana gun1-1gun5-1 double mutant seedlings with gun phenotype associated with both lincomycin and norflurazon demonstrate a repressed root growth when germinated on lincomycin but not norflurazon-containing media. Statistical analysis has demonstrated a high negative correlation between root length and gun phenotype evaluated on both LHCB1.2 and HEMA1 genes expression in three gun mutants of Arabidopsis: gun1-1, cch1-1 and the double mutant gun1-1gun5-1. Our results demonstrate that regulatory signals of plastid origin might participate in root development.

The catalytic performance of zirconium-based metal–organic frameworks (UiO-66, UiO-67, and MOF-801) in cyclohexene oxidation with aqueous hydrogen peroxide can be greatly improved by adding a sourc...

Background. Predicting outcomes in infants with surgical bowel disease based on routinely monitored indicators is an unresolved problem. Objectives. To create a predicting model of the probability of survival in newborns with surgical pathology of the intestine by using the method of logistic regression. Material and methods. The study involved 77 newborns with acute gastrointestinal pathology. All patients were divided into two groups according to the outcome. Analyzed parameters: gestational age, birth weight, dynamic evaluation of multiple organ failure at the study stages. Ranging of predictors is done using the Forward method. The predicting model is developed by the method of logistic regression. A critical level of significance is p < 0.05. Results. High rates of gestational age (p = 0.002) and assessment of multi-organ failure on the NEOMOD scale at stage 3 (p = 0.000) had high predictive power. Body weight at birth did not show a significant effect on outcome. Conclusions. The outcome predicting in neonatal surgery is possible at the stage of short-term prognosis. Independent significant predictors are the duration of gestation and the severity of multiple organ failure in newborns.

The structure and photoluminescence of CH3NH3PbI3 (lead triiodide methylammonium) synthesized perovskite crystals are investigated in a wide temperature range. As temperature rises to 130–140 K, there is a junction from an orthorhombic to tetragonal crystal lattice with a change in the bandwidth. An increase in the stationary photoluminescence intensity at room temperature under the influence of exciting emission is revealed. A model explaining the observed growth of photoluminescence is proposed.

Objectives To estimate the incidence of microbial keratitis in children wearing overnight orthokeratology lenses in Moscow, Russia. Methods To estimate the number of children wearing overnight orthokeratology lenses in 2018, 1,368 patient records from 13 Doctors Lens clinics were selected at random and extrapolated to the entire patient base. To identify cases of microbial keratitis, all episodes of infiltrative keratitis from Morozovskaya City Children's Clinical Hospital in 2018 were recorded and adjudicated by three experienced ophthalmologists. Incidence was calculated as the number of cases divided by the estimated number of wearers. Results There were 23,049 overnight orthokeratology fits between 2010 and 2018. Among the 1,368 records surveyed, 1,078 (79%) were younger than 18 years at initial fitting. Based on a 7% or 10% annual discontinuation rate, the estimated number of children wearing lenses in 2018 was 10,307 or 9,422, respectively. During 2018, there were 139 cases of corneal infiltrative keratitis in children and 45 were adjudicated as microbial keratitis (32%). Of these, 20 cases were associated with contact lens wear (44%): 15 soft lens wearers (33%) and 5 overnight orthokeratology wearers (11%). Based on the 5 cases and assuming a 7% or 10% discontinuation rate, the annual incidence is 4.9 (95% confidence interval[CI]: 2.1-11.4) or 5.3 (95% CI: 2.3-12.4) per 10,000 patient years. Conclusion The incidence of microbial keratitis in children wearing overnight orthokeratology is lower than a previous United States study and similar to rates associated with use of daily wear soft contact lenses.

Mesoporous zirconium-silicates have been prepared using two different methodologies, evaporation-induced self-assembly and solventless organometallic precursor dry impregnation of commercial SiO2. The samples were characterized by elemental analysis, XRD, N2 adsorption, TEM, DRS UV–vis and Raman spectroscopic techniques. The catalytic performance of the Zr-Si catalysts was assessed in the epoxidation of three representative alkenes, cyclohexene, cyclooctene and caryophyllene, as well as in the oxidation of methyl phenyl sulfide using aqueous hydrogen peroxide as a green oxidant, with special attention drawn to the structure/activity relationship and catalyst stability issues. The key factors which affect substrate conversion and epoxide selectivity have been defined. The catalysts with larger contents of oligomeric ZrO2 species revealed higher activity. The nature of alkene and, in particular, its molecular hindrance is crucial, since the adsorption of the epoxide product is the main factor leading to fast catalyst deactivation. In fact, bulky epoxides do not show this effect. After optimization, the oxidation of caryophyllene gave endocyclic monoepoxide with 77% selectivity at 87% alkene conversion. Methyl phenyl sulfoxide afforded 37% of sulfoxide and 63% of sulfone at 57% sulfide conversion. The nature of catalysis was truly heterogeneous and no Zr leaching was observed.

The spatial-temporal organization of the activation, repolarization and hemodynamics of the heart ventricle in rainbow trout, Oncorhynchus mykiss, adapted to a temperature of 5-7 °C, were studied from the normal sinus rhythm (21.6 ± 4.9 bpm) to the highest possible heart rhythm (HR) (60 bpm), during which deterioration of the contractile activity of the myocardium occurred. Regardless of the HR, the main pattern of excitation of the heart ventricle was the movement of the depolarization wave from the dorsal areas of the base in the base-apical and ventral directions with the capture of the entire thickness of the walls, with a slight difference in the time of activation of the subendocardium compared to the subepicardium. The increase in HR above the sinus rhythm caused significant shortening of local repolarization durations in all areas and layers (endocardial, intramural and subepicardial) of the heart ventricle. Changes in local durations of repolarization led to an increase in the heterogeneity of repolarization of the ventricular myocardium; as a result, a deterioration of its contractility was observed. In relation to the sinus rhythm, the maximal systolic pressure in the heart ventricle decreased, the diastolic and end-diastolic pressure increased, and the maximum rates of pressure rise and fall decreased. In rainbow trout adapted to a temperature of 5-7 °C at sinus rhythm, the pumping function of the heart was probably within the upper limit of the physiological norm, and a further increase in the heart rate led to a decline in myocardial contractility.

Background Plant mitochondrial genomes (mitogenomes) can be structurally complex while their size can vary from ~ 222 Kbp in Brassica napus to 11.3 Mbp in Silene conica. To date, in comparison with the number of plant species, only a few plant mitogenomes have been sequenced and released, particularly for conifers (the Pinaceae family). Conifers cover an ancient group of land plants that includes about 600 species, and which are of great ecological and economical value. Among them, Siberian larch (Larix sibirica Ledeb.) represents one of the keystone species in Siberian boreal forests. Yet, despite its importance for evolutionary and population studies, the mitogenome of Siberian larch has not yet been assembled and studied. Results Two sources of DNA sequences were used to search for mitochondrial DNA (mtDNA) sequences: mtDNA enriched samples and nucleotide reads generated in the de novo whole genome sequencing project, respectively. The assembly of the Siberian larch mitogenome contained nine contigs, with the shortest and the largest contigs being 24,767 bp and 4,008,762 bp, respectively. The total size of the genome was estimated at 11.7 Mbp. In total, 40 protein-coding, 34 tRNA, and 3 rRNA genes and numerous repetitive elements (REs) were annotated in this mitogenome. In total, 864 C-to-U RNA editing sites were found for 38 out of 40 protein-coding genes. The immense size of this genome, currently the largest reported, can be partly explained by variable numbers of mobile genetic elements, and introns, but unlikely by plasmid-related sequences. We found few plasmid-like insertions representing only 0.11% of the entire Siberian larch mitogenome. Conclusions Our study showed that the size of the Siberian larch mitogenome is much larger than in other so far studied Gymnosperms, and in the same range as for the annual flowering plant Silene conica (11.3 Mbp). Similar to other species, the Siberian larch mitogenome contains relatively few genes, and despite its huge size, the repeated and low complexity regions cover only 14.46% of the mitogenome sequence.

Vesicle-templated nanocapsules offer a unique combination of properties enabled by robust shells with single-nanometer thickness containing programmed uniform pores capable of fast and selective mass transfer. These capsules emerged as a versatile platform for creating functional devices, such as nanoreactors, nanosensors, and containers for the delivery of drugs and imaging agents. Nanocapsules are synthesized by a directed assembly method using self-assembled bilayers of vesicles as temporary scaffolds. In this approach, hydrophobic building blocks are loaded into the hydrophobic interior of vesicles formed from lipids or surfactants. Pore-forming templates are codissolved with the monomers and cross-linkers in the interior of the bilayer. The polymerization forms a cross-linked shell with embedded pore-forming templates. Removal of the surfactant scaffold and pore-forming templates leads to free-standing nanocapsules with shells containing uniform imprinted nanopores. Development of reliable and scalable synthetic methods for the modular construction of capsules with tunable properties has opened the opportunity to pursue practical applications of nanocapsules. In this Account, we discuss how unique properties of vesicle-templated nanocapsules translate into the creation of functional nanodevices. Specifically, we focus the conversation on applications aiming at the delivery of drugs and imaging agents, creation of fast-acting and selective nanoreactors, and fabrication of nanoprobes for sensing and imaging. We present a brief overview of the synthesis of nanocapsules with an emphasis on recent developments leading to robust synthetic methods including the synthesis under physiological conditions and creation of biodegradable nanocapsules. We then highlight unique properties of nanocapsules essential for practical applications, such as precise control of pore size and chemical environment, selective permeability, and ultrafast transport through the pores. We discuss new motifs for catch and release of small molecules with porous nanocapsules based on controlling the microenvironment inside the nanocapsules, regulating the charge on the orifice of nanopores in the shells, and reversible synergistic action of host and guest forming a supramolecular complex in nanocapsules. We demonstrate successful creation of fast-acting and selective nanoreactors by encapsulation of diverse homogeneous and nanoparticle catalysts. Due to unhindered flow of substrates and products through the nanopores, encapsulation did not compromise catalytic efficiency and, in fact, improved the stability of entrapped catalysts. We present robust nanoprobes based on nanocapsules with entrapped sensing agents and show how the encapsulation resulted in selective measurements with fast response times in challenging conditions, such as small volumes and complex mixtures. Throughout this Account, we highlight the advantages of encapsulation and discuss the opportunities for future design of nanodevices.

The catalytic oxidation of methane over nickel foil is studied. It is shown that, under the oxygen-lean conditions in the regime of a flow-type reactor, nonlinear phenomena can appear in the form of self-sustained oscillations of the reaction rate and the catalyst temperature. To determine the reasons for self-sustained oscillations, X-ray diffraction and mass spectrometry in the operandо mode were used. It was found that the appearance of oscillations in the methane oxidation is due to periodical oxidation–reduction of the surface layer of nickel foil; metallic nickel has a higher catalytic activity than NiO. The oscillations of the catalyst temperature are determined by the occurrence of exothermic and endothermic processes associated with the reduction of nickel oxide and methane oxidation on the surface of metallic nickel.

Here we have studied the kinetics of the ethylene non-catalytic decomposition on the surface of multi-walled carbon nanotubes (MWCNTs) leading to the formation of lateral carbon deposits (LCD). Despite the comprehensive data on the gas-phase pyrolysis and a clear presence of surface impurities formed of carbon deposits, this process has not gained any proper attention. Within the temperature range studied (650–750 °C), we have found the rate of the reaction to be proportional to the MWCNT surface area and ethylene partial pressure. The activation energy of carbon deposition is close to that for the collision of two ethylene molecules to form C2H5· and C2H3· radicals. Based on the data obtained, we have proposed the radical mechanism of the formation of the deposits. High-resolution TEM, synchrotron radiation XRD, Raman spectroscopy, differential thermal analysis, temperature dependence of conductivity, and surface area measurements were used to characterize the structure and properties of the carbon-carbon composite produced. We have shown the deposition of lateral carbon to be a soft non-destructive technique for MWCNT surface functionalization allowing one to tune the properties of 3D-structured nanotube materials (e.g. arrays or aerogels). As an example, the LCD coating gradually changes the conductivity mechanism to 3D variable range hopping.