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The description and test results of the prototype of a fast ionosonde for the vertical sounding of the ionosphere, which makes it possible to record ionograms once a second, are presented. Such a high rate of registration of ionograms is required to study the fast processes of redistribution of electron concentration during heating experiments, for registration of fast quasiperiodic and moving ionospheric disturbances in the F, E, and Es layers. The key feature of the presented development is the usage of publicly available radio-electronic components. This provided a significant reduction in the cost of creating the prototype. In the current version, the prototype is based on the software-defined radio (SDR) devices Red Pitaya SDRlab 122-16 and LimeSDR. The test results showed that the quality of the ionograms recorded using the prototype is not worse than the quality of ionograms recorded using the professional CADI ionosonde. The low cost of the components allows providing multi-position registration of ionograms for determination the dynamics of natural and artificial ionospheric disturbances in 3D region of space at a lower expenses rate, as well as to create a network of ionospheric observation points with an increased number of ionosondes.

In December 2021, we presented a prototype of a fast ionosonde for vertical sounding based on the usage of publicly available radio-electronic components. This approach led to a major reduction in the cost of the created device. We called our development ION-FAST, which characterizes the key feature of the ionosonde: the possibility of continuous operation at a speed of one ionogram per second, which is required to study the rapid processes of redistribution of the electron concentration during heating experiments. In May 2022, an ionosonde for vertical sounding of the ionosphere, developed at the Radiophysical Research Institute of Nizhni Novgorod (NIRFI), was put into continuous operation at the SURA facility. This report provides a description of the improvements made to the prototype over the last year and the path to be passed from idea to implementation. The results of the first months of the prototype’s operation (especially the results of the supporting optic experiment in August 2022), as well as prospects for further use and modernization, are provided. In addition, the realization of the oblique chirp-sounding receiver prototype as an extension of the proposed diagnostic platform’s functionality, including the first results, is presented.

Article —This article describes the construction, principles of operating, and characteristics of the TOTEM- electron spectrometer developed for the Strannik complex of scientific instruments for the Resonance - MKA space project. In the article, analytical characteristics are presented of the qualification model of the instrument, which fully corresponds to the flight unit, and the procedure for functional tests of the instrument is described. The article also describes the structure and principles of functioning of the hardware and software laboratory facility developed for ground calibrations and tests of such a type of instruments. The design of the TOTEM-E instrument offers a new approach to measuring particle fluxes, which allows the accuracy and speed of measurements to be increased. A feature of the proposed scheme is the possibility of simultaneous measurement of electron fluxes in a plane section in the velocity space in the energy range from E 0 to 6.5 × E 0 , where E 0 is the minimum particle energy recorded by the instrument. This is achieved by using two conical electrostatic mirrors that take electrons from a flat 360° flow section for subsequent energy analysis and using a coordinate-sensitive detector for simultaneous particle registration.

Quantitative and qualitative characteristics of cones and seeds and the emergence and survival of seedlings in the Siberian larch (Larix sibirica Ledeb.) have been studied in different parts of the ecotone at the upper boundary of arboreal vegetation (treeline ecotone) on Serebryanskii Kamen’ Mountain (Northern Urals) and on the hills (with a landmark 312 m above sea level) surrounding Chernaya Mountain (Polar Urals) from 2005 to 2011. We have found a decrease in the parameters of cones, number of seeds in the cones, their viability in laboratory with an increase in altitude, and differences in the number of seedlings between parts of the treeline ecotone. It is shown that the formation of Siberian larch generations on the Northern Urals occurs only after moist years. It is noted that, in the Polar Urals, Siberian larch produces a big seed crop every 2–3 years. It is proven that the seed production and mortality of seedlings in Siberian larch are influenced not only by air temperature and soil moisture, but also by wind load, snow depth, and soil temperature rapidly changing along the slope.

— ARIES-L is a wide-angle ionic energy-mass analyzer that provides measurements of ion parameters in the energy range from 10 eV to 5000 eV, and can record the flux of neutral atoms from the lunar regolith. A distinctive feature of the instrument is the ability to simultaneously detect ions of the selected energy in a field of view close to 2π. Within the framework of the Luna-25 mission, the tasks of ion energy-mass analyzer ARIES-L is the study of the interaction of the solar wind with the regolith, the study of the regolith using secondary ion mass spectrometry and the determination of the flux of neutral atoms from the regolith caused by the action of charged particles. The field of view of the instrument close to 2π permits recording both the fluxes of solar wind ions and secondary particles from the regolith, which makes it possible to study the processes of interaction of primary fluxes of charged particles with regolith depending on the angle of incidence, which changes during the lunar day. The instrument will also allow measurements in magnetospheric plasma.

Possible ways of high-accuracy reproduction of specified values of the optical attenuation in fiber-optic attenuators with discrete attenuators are examined. Design-technology and algorithm methods are used to reduce the errors in discrete attenuators.

The patterns of formation of RNA nanoparticles (NPs) during thermal cycling of bacterial total tRNA in the presence of cations Ca2+, Mn2+, Ni2+, Zn2+, Co2+, and Cu2+ were studied. The optimal conditions for the production of NPs were found, and it was revealed that their size depends on the ratio of the concentrations of Me2+ and tRNA. The concentration of reagents for obtaining NPs of small size (from 5 to 100 nm) was selected. It was shown that tRNA-based nanoparticles can comprise short (20–50 nt) ribooligonucleotides, including aptamers and siRNAs. The stability of NPs during storage in buffer solutions of various composition was studied. It was found that the initial suspensions of NPs are quite stable, but they are rapidly destroyed in PBS buffer (pH 7.4). A simple and effective stabilizer (polyarginine) was found, the additives of which ensure the preservation of nanoparticles in PBS buffer for more than 5 h. Nanoparticles modified with the stabilizer are resistant to blood serum nucleases and can be used for transfection.

In mountainous regions, climate warming is expected to shift species' ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe's major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras' spedes richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (-1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region.

Focusing on mountain plant communities across Europe, a study shows that ongoing climate change causes a gradual decline in cold-adapted species and a corresponding increase in warm-adapted species, which could be an early sign that mountain plant diversity is at risk. Climate impact studies have indicated ecological fingerprints of recent global warming across a wide range of habitats 1 , 2 . Although these studies have shown responses from various local case studies, a coherent large-scale account on temperature-driven changes of biotic communities has been lacking 3 , 4 . Here we use 867 vegetation samples above the treeline from 60 summit sites in all major European mountain systems to show that ongoing climate change gradually transforms mountain plant communities. We provide evidence that the more cold-adapted species decline and the more warm-adapted species increase, a process described here as thermophilization. At the scale of individual mountains this general trend may not be apparent, but at the larger, continental scale we observed a significantly higher abundance of thermophilic species in 2008, compared with 2001. Thermophilization of mountain plant communities mirrors the degree of recent warming and is more pronounced in areas where the temperature increase has been higher. In view of the projected climate change 5 , 6 the observed transformation suggests a progressive decline of cold mountain habitats and their biota.