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The Laptev Sea and the East Siberian Sea are remote areas of the Arctic region where detailed data on phytoplankton composition and spatial distribution remain limited. In the context of the ongoing environmental changes (increasing warming and ice melting) and prospective exploration activities (oil and gas production) on the Arctic shelves, understanding of the seasonal and interannual phytoplankton community dynamics is of critical importance. Our study provides new specifying data on species composition of phytoplankton over the vast area of the Laptev Sea shelf and the East Siberian Sea shelf. We found that the outer shelf of the Laptev and East Siberian seas was characterized by typical late spring diatom species (Chaetoceros furcellatus, Chaetoceros diadema, Chaetoceros debilis, Chaetoceros constrictus). On the inner shelf of the Laptev Sea, which is strongly affected by the Lena River water masses, the phytoplankton were characterized by the transition from the summer to an autumn stage of development. Local algal assemblages were composed by mixo- and heterotrophic dinoflagellates (Dinophysis and Protoperidinium genera) together with marine and brackish water-marine diatoms (Thalassiosira hyperborea, Thalassiosira baltica, Thalassiosira gravida, Thalassiosira nordenskioeldii) accompanied by sporadically occurring freshwater riverine planktonic diatom species (Aulacoseira granulata, Aulacoseira italica, Asterionella formosa). These variations in species composition over the Laptev Sea shelf were attributed to differences in the hydrography, marine chemical conditions, and the sea-ice regime.

Peculiarities of porous silicon layers formation during electrochemical etching of p-type silicon were studied. Principal divisions of pore formation mechanisms in n-type and p-type of silicon were demonstrated.

The problem of space debris disposal is becoming more and more urgent with the increasing availability of research related to the launch of spacecraft into outer space. In addition to destroying the objects that are already moving in orbit, it is necessary to prevent the appearence of new ones. So there is a need to equip spacecraft with recycling systems. As such, it is possible to use an inflatable aerodynamic accelerator, which is a thin-walled shell, compactly packed in a container. The paper presents the results of designing the housing of an inflatable aerodynamic accelerator, and considers possible options for the shell deployment system.

A model of the chemical interaction of Si with the (HF2)– ion was propsoed to explain some experimental data on the formation of porous silicon.

The change in the photoluminescence peaks of porous silicon at λ = 640–670 and 540–560 nm at 300 and 77 K, as well as their behavior after low-temperature annealing of the samples at 500°С, has been studied. The change in these peaks correlated with that in the IR spectra. The peak at 640–670 nm has been explained by the existence Si–OH groups on the porous silicon layers and the peak at 540–560 nm, by the photoluminescence of the silicon matrix per se.

Features of the formation of porous silicon layers during anodic etching of p-Si were considered. A fundamental difference between the mechanisms of the formation of nanostructured layers on p-and n-Si was shown.

We present new and more complete information than previously available on the pelagic fauna of the Lena River Delta, eastern Siberia. Zooplankton samples collected between 2000 and 2011 from 11 varied aquatic habitats on Samoylov Island have been examined and clear differences noted between the zooplankton communities in different types of tundra waterbody. Well-marked synchronism in the development of common species populations was, however, revealed by analysis of their life cycles. The pelagic fauna of the investigated aquatic ecosystems is heterogeneous in origin, consisting mainly of aboriginal Arctic species but also including invasive species from more temperate latitudes and relicts of ice-age fauna. One hundred and twenty-five zooplankton taxa belonging to Rotifera (67) and Arthropoda (58) phyla were identified. Five Copepoda species and seven Cladocera species were recorded for the first time in the Lena River Delta; the presence of most of these species in the delta’s aquatic ecosystems is associated with Lena River water influx during spring flood. Two calanoid copepods, Eurytemora arctica Wilson and Tash and Eurytemora foveola Johnson, are new species to Palearctic pelagic fauna, previously known only from the Nearctic. The data obtained provide new confirmation that the last glaciation had a marked influence on microcrustacean distributions within the Arctic.

The space debris problem is becoming more and more relevant with the increasing availability of space. Thus, the necessity to equip new spacecrafts with special disposal devices arises. One of the possible ways to dispose of a disabled satellite is its transferring to the dense atmosphere using decelerator devices. Design and technology issues of small spacecraft’s inflatable aerodynamic decelerator (IAD) were analyzed.

Space debris is a growing concern that becomes more urgent with the increase in space exploration. This is the reason for equipping spacecraft with disposal systems. One of the methods for space debris removal is deorbiting a small spacecraft by using a decelerator. This paper presents issue analysis related to a selection of design and technology solutions and temperature analysis for inflatable aerodynamic decelerator of small spacecraft.

Variations in the contours of pores produced in n-type silicon by electrochemical etching in hydrofluoric acid solutions are interpreted in terms of the mechanism underlying the chemical interaction of the etchant with silicon and the anisotropy of the etchant–silicon system. Mathematical expressions are proposed which describe the contours and limiting radial sizes of pores forming at the very beginning of the etching process (~10–15 s).

The effect of the type of Si conductivity on the initiation and formation of pores in silicon samples during electrochemical etching was studied. The difference between the pore formation processes in n- and p-conducting silicon was attributed to the properties and the nature of layers formed in the initial period of etching on the Si surface. A possible composition of the layers formed on the Si surface was proposed considering the chemistry of Si interaction with the etching agent.

The effect of thermal annealing of porous silicon layers in various media with subsequent exposure to air on the photoluminescence spectra of the layers was described.

A mechanism is suggested for pore formation in n-type Si through the stage of nucleation in the most probable places.

Small spacecraft, first of all, nanosatellites of a CubeSat standard have a relatively small operational life. After their operational lives have expired, they turn into space debris. Disabled spacecraft can be transferred to the disposal orbit in the dense atmosphere using inflatable decelerators in order to avoid pollution of the near-Earth space. Decelerator’s temperature state is formed under the action of thermal radiation from the Sun and the Earth and kinetic heating caused by movement in a free-molecular medium. The specific features of heat transfer of inflatable decelerator’s thin-walled spherical shell are considered. The inflatable decelerator is designed for spacecraft removal during moving in the low-earth orbit.

A stepwise scheme has been proposed for gaining insight into the nanopore formation process in silicon during electrolytic etching in hydrofluoric acid solutions. We have studied the influence of the concentration and nature of dopants (phosphorus, arsenic, and antimony) in silicon, current density, electric field strength, and etching time on the axial and radial pore sizes and the pore distribution density. The dopants have been shown to play a predominant role in the nanopore formation process. The shape and spatial orientation of nanopores in Si substrates with the (100) and (111) crystallographic orientations have been interpreted in terms of specific features of the electrochemical etching of silicon in hydrofluoric acid solutions, related to the action of the etching ion (HF2)−. The observed discrepancy between the experimentally determined and calculated radial nanopore sizes has been accounted for by the low probability ( 6.25%) of simultaneous interaction of the fluorine atoms of an (HF2)− ion with the corresponding silicon atoms located at vertices of a cube of the crystal lattice.

A model was proposed for the mechanism of the chemical interaction of the etchant ion (HF2)– with silicon during its electrochemical etching, which explains the possibility of porous silicon etching in the dark and the formation of hydride and hydroxyl groups on the silicon surface.

The role of the etchant ion (HF2)– in the formation of pores in silicon during its etching in hydrofluoric acid solutions has been elucidated. The pore shape, size, and orientation in (100) and (111) silicon substrates have been explained by specific features of the etchant ion (HF2)–.

The effect of the HF content on the formation of nanopores in silicon during electrochemical etching was studied. Nanoporous silicon layers were established to be formed only when hydrogen fluoride content in etchants (initial HF content: 49 wt %) was higher than 10–12 vol %. The mass and charge balance of the electrolytic etching of silicon was calculated, and the change in charge number of reaction (effective silicon valence) was determined depending on the HF content. The obtained data were used to propose a silicon etching model with the formation of SiF4 and nanoporous silicon (where nanopores were formed due to the action of predominantly (HF2)− ions).

The shape of nanopores formed in silicon upon electrochemical etching in hydrofluoric acid solutions has been explained by the effect of anisotropy of the components involved in etching. A semiempirical formula that allows one to characterize, with a certain accuracy, the degree of anisotropy of the etchant–silicon system and describe the shape of the resulting pores has been suggested.

Among children of early age still severe forms of a disease which can lead to lethal outcomes are registered still most often. Untimely diagnostics and the wrong assessment of the severity of pertussis cause mistakes in treatment and are significantly impact on a disease outcome. The analysis of features of a course of pertussis in children of early age is based on supervision over 670 children hospitalized in Moscow Infectious Clinical Hospital No. 1. Studying of clinic picure of pertussis in comparative evolutionary aspect allowed to establish the main reasons for an adverse course of pertussis a lethality at the present stage. The main factors promoting development of severe forms of a Bordetella pertussis infection in children of early age are the anatomical and physiological features, the burdened premorbid background, accompanying infectious diseases and biological properties of circulating strains of a Bordetella pertussis microbe. Pertussis in children of early age has own the clinical features, being characterized first of all by severity of the disease course. The most significant options of a mixtinfection are a combination of pertussis with CMV infection, the RS-infection.

Based on main principles of porous silicon (por-Si) formation the research of producing containers for drug delivery systems was launched. Nanoparticles for loading medicine were obtained.

If gene regulatory processes form the basis of phenotypic plasticity that evidences itself as discrete adaptive norms (sensu developmental conversion), it seems evident that the forms capable of such adaptations would possess a correspondingly richer genome than those lacking such adaptations. We examine evidence for the existence of genetic triads which are comprised of one form with wide niches due to phenotypic plasticity and two forms, each which is genetically fixed and exhibits a phenotype at one of the extremes of the plastic form. The invasion of organisms into new environments may occur by acquisition of discrete adaptive norms (DAN), which enable a transition between the old and new environments. The horohalinicum (=critical salinity) is defined as a salinity zone which always corresponds to 5–8 ppm and divides freshwater and marine faunas and floras, as well as many other physico-chemical characteristics. The current paper explores the existence of discrete adaptive norms and genetic triads with respect to salinity in some euryhaline crustaceans, particularly the arctic copepods, and discusses how such adaptations might inform us about species boundaries that affect the taxonomic status of these forms.

New evidence was received concerning the composition, distribution and abundance of zooplankton in May-June 1996 in the shelf area of Laptev Sea. The minimal depth of area is 6 m, the maximum 33 m. As measured at various stations, ice thickness ranges between 1.20 and 2.07 m. Species diversity of spring-time zooplankton is represented by 23 taxa of marine, brackishwater and freshwater species. Average abundance of zooplankton across the examined area in May amounted to 155 individuals per m3. From records of most stations, brackishwater plankton (mass species Drepanopus bungei) was predominantly abundant, being at the time in the stage of reproduction. Induced by spring flood, variations in hydrologic conditions in June have resulted in quantitative and qualitative changes in zooplankton community. Brief analysis of the population structure and development biology of some mass species in the shelf zone of Laptev Sea was made on the basis of previous and newly obtained data.