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Background The Nile rat (Avicanthis niloticus) is an important animal model because of its robust diurnal rhythm, a cone-rich retina, and a propensity to develop diet-induced diabetes without chemical or genetic modifications. A closer similarity to humans in these aspects, compared to the widely used Mus musculus and Rattus norvegicus models, holds the promise of better translation of research findings to the clinic. Results We report a 2.5 Gb, chromosome-level reference genome assembly with fully resolved parental haplotypes, generated with the Vertebrate Genomes Project (VGP). The assembly is highly contiguous, with contig N50 of 11.1 Mb, scaffold N50 of 83 Mb, and 95.2% of the sequence assigned to chromosomes. We used a novel workflow to identify 3613 segmental duplications and quantify duplicated genes. Comparative analyses revealed unique genomic features of the Nile rat, including some that affect genes associated with type 2 diabetes and metabolic dysfunctions. We discuss 14 genes that are heterozygous in the Nile rat or highly diverged from the house mouse. Conclusions Our findings reflect the exceptional level of genomic resolution present in this assembly, which will greatly expand the potential of the Nile rat as a model organism.

We report a new environmentally friendly and simple method to produce monolithic magnetic composites C/Ni nanoparticles (NiNPs) consisting of highly porous carbon matrix and well-separated Ni nanoparticles covered by graphite-like shells. The method is based on the carbonization of wood with addition of nickel nitrate and wood decomposition product (tar) as a binder. The specific structural features and magnetic properties of the C/NiNPs composites are systematically investigated. We have demonstrated the change in average size of NiNPs from ~ 9 to ~ 18 nm and in their magnetic character from superparamagnetic to ferromagnetic behavior by changing the pyrolysis temperature. The macroscopic magnetization 3.5 emu/g (38 emu/g(Ni)) of the obtained porous monolithic nanocomposites with small amount of nickel (8.8 wt.%) in low magnetic field and their ferromagnetic behavior at room temperature make them ideal candidates for use in applications involving magnetic separation (heterogeneous catalysis, adsorption of contaminants in aqueous media, etc.). The resulting maximum magnetization 38 emu/g(Ni) of carbon-encapsulated NiNPs is comparable and even somewhat exceeds that of similar core–shell Ni nanoparticles obtained by other methods. The fundamental question arises whether it is possible to achieve the magnetization for carbon-encapsulated NiNPs as that in the bulk Ni.

The impurity cluster formation in 64Zn+ ion hot-implanted and subsequently thermal-oxidized Si substrates are studied. After implantation on sample surface and in sample near-surface layer, the metallic Zn clusters with the average size near 200 nm on sample surface and the clusters with size about 20 nm in a sample body were created. After annealing at 700 °C, there was transformation from metal Zn clusters to its oxide form such as ZnO(core)/Zn2SiO4(shell) on a sample surface and conservation of the metallic Zn phase in a sample body. We propose an explanation of this phenomenon by temperature dependence of the oxygen molecules diffusion in silicon body and zinc atom opposite moving to the sample surface during annealing.

The influence of the adjacent layers (SiO2, Al, Ni, Ti, W, TiN, TiN/W) on the crystallization kinetics of Ge2Sb2Te5 thin films was investigated using the techniques based on the application of two different methods—differential scanning calorimetry and measurements of the resistivity temperature dependences. Thin films were deposited by the magnetron sputtering. The composition of the films was determined by the Auger spectroscopy and was close to Ge2Sb2Te5. X-ray diffraction was used to investigate the structure of thin films and showed that the as-deposited films were in an amorphous state, while heat treatment at 250 °C for 30 min led to the crystallization to the cubic (rock salt) phase. Effective activation energy of crystallization obtained by differential scanning calorimetry at the beginning of the crystallization was 1.8 eV and then slightly decreased to 1.7 eV at the end of the process. The values of the effective activation energy obtained from the measurements of the resistivity temperature dependences were in the range of 2.5–2.9 eV at the beginning and in the range of 2.2–3.5 eV at the end of the crystallization process. The difference in the effective activation energies of crystallization for the GST225 thin films deposited on the different sublayers is caused by the influence of the neighboring sublayers on the crystallization process. It was found that crystallization temperatures correlate with the effective activation energies and increase with their growth.

Adaptive behavior of lactobacilli in cultured in microchambers of different design was analyzed under a light microscope. We found that the time of appearance of first-generation cells for the studied strains of lactobacilli differed in chambers with different rheological properties (stationary and flow-through). The results of our experiments suggest that the development of populations of lactobacilli is regulated by autometabolites of different physiological modalities directly from the very first cell generations. Populations of lactobacilli are under the control of autometabolites at the initial stages of interaction with the environment under various rheological conditions. Rheological conditions of the culture medium of the first generation cells determine the development of cells of the second and probably further cell generations under the same culturing conditions.

It is determined that the cost of sold goods and services in the market of goods, taken into account by the statistics on the nominal gross domestic product and the price index allows estimating the market value of production capital in the national currency. National accounts also take into account the costs of productive capital and fixed capital stocks, which are valued by their market value. It is shown that when the discounted capital is underestimated as compared to the market value, the money in circulation serves turnover only and does not ensure the reproduction of capital. It is also shown that economic growth and technological progress is possible when the value of the recorded production capital is no less than its market value.

Despite successful examples of multilevel government leadership on climate change policy, many local officials still face a variety of barriers, including low public support, low resources, and political division. But perhaps most significant is lack of public discussion about climate change. We propose deliberative framing as a strategy to open the silence, bridge political division, identify common and divergent interests and values, and thereby devise collective responses to climate change.

The general aspects of the mechanical activation (MA) of Al/CuO thermite compositions based on micron-sized particles and nanopowders of the starting components have been analyzed using X-ray diffraction and hydrogen titration. The latter method has been employed to evaluate the amount of residual oxygen in CuO and Cu2O from the weight loss during heating in H2. The reactivity of the activated mixtures was assessed using DSC and TG in combination with mass spectrometric analysis. In addition, we have measured the ignition temperature, burning velocity, and brightness temperature of the reaction products. The results demonstrate that mechanical activation leads to the fragmentation of the components, mixture homogenization, and the formation of a composite, producing “weakly bound” oxygen in CuOn and causing partial reaction between the components. The total exothermic heat effect in DSC scans, burning velocity, and brightness temperature as functions of specific milling dose (D) have an extremum. The highest reactivity is observed near D = 2 kJ/g, where a sufficient defect density in the components and good mixture homogenization are ensured, but the degree of MA-induced conversion does not exceed 10%. The burning velocity then reaches 400–700 m/s, and the brightness temperature is 3400–3800 °C. The milling dose dependence of the self-ignition temperature has no extremum. The self-ignition temperature steadily decreases with increasing milling dose, even though the ignition knock “power” falls off. The use of nanoparticulate starting components does not appear reasonable.

Deflation in economy is defined as a result of reduction of the amount of money in circulation by the Central Bank and the financial sector, which violated the equilibrium. The equilibrium can be restored by the market system in the process of regulating the production of goods through reduction in the number of employed in the production sector in the context of consumer demand. To restore the growth of production of goods and overcome deflationary period, the Central Bank, at the cost of capital employed in production, should establish the amount of money in circulation that ensures the necessary level of inflation. As a result, overcoming the deflation leads to a financial catastrophe with high unemployment and hyperinflation.

The use of the nanostructured nanocomposites aims to improve the peak figure of merit (ZT) values of thermoelectric alloys. In addition to ZT, the coefficients of the thermal linear expansion (CTLE) of these alloys are equally important for estimating stresses imposed by the thermal cycling inherent to waste heat recovery operations. In this study, we report the calculated “technical alpha”, i.e., the experimental mean CTLE values for the bulk nanostructured n-type Si80Ge20 alloy doped with phosphorus at 298–1220 K. The elemental composition of the spark plasma sintered (SPS)-specimen after thermal cycling in the infrared furnace is characterized by means of AES spectroscopy in combination with ion sputtering. Small amounts of contaminants, such as Fe and O, and large losses of P are detected. Elongations have been measured using ULVAC DL-1500-RH high-speed dilatometer with various rates of heating and cooling. Anomalous thermal behavior of the n-type Si80Ge20(P2.2) composite is observed at high temperatures. Previously, the same anomaly was detected in the temperature dependence of the elongation of pure silicon. There are some discrepancies between our measurements of the thermal expansion of nanostructured n-SiGe composites and those reported in the literature. Moreover, in this study, SiGe solid solution is also studied to verify the additive scheme and to explore deviations from it for predicting CTLE values at higher temperature on the basis of the properties of the pure components. These calculations of the CTLE of undoped SiGe alloys match with the results of the dilatometric and X-ray experiments conducted during the period 1964–1987 and the calculations based on other theoretical approaches.

The combined effects of climate and land-use change have changed both the hydrology and management of endorheic watersheds globally. Devils Lake (DL), North Dakota, USA, has risen nearly 10 m since 1991, resulting in a costly, lengthy and litigious water management issue in the region. With more than 1 billion US dollars already spent in mitigation, DL is less than 2 m from its uncontrolled overspill to the nearby Sheyenne River, which could lead to mounting economic, environmental and social costs. While previous studies have generally attributed the changes in the hydrology of DL to the current wet spell, the impacts of land-use changes have not been investigated. Using a hydrological model, here we develop four land-use alternatives driven by market and policy conditions in the DL watershed and investigate their effects on DL hydrology and overspill probability under historic and changed climates. Land-use scenarios under an ensemble of statistically downscaled general circulation model projections indicate a higher overspill risk (7.4–17.0 vs. 0–2 %) under historical climate. Incentivized grass and alfalfa scenarios were able to moderate the hydrological implications to DL under a changed climate, indicating their potential companion roles in DL flood mitigation strategies.

This paper reports a facile and green method for conversion of graphene oxide (GO) into graphene by low-temperature heating (80 °C) in the presence of a glass wafer. Compared to conventional GO chemical reduction methods, the presented approach is easy-scalable, operationally simple, and based on the use of a non-toxic recyclable deoxygenation agent. The efficiency of the proposed method is further expanded by the fact that it can be applied for reducing both GO suspensions and large-scale thin films formed on various substrates prior to the reduction process. The quality of the obtained reduced graphene oxide (rGO) strongly depends on the type of the used glass wafer, and, particularly, magnesium silicate glass can provide rGO with the C/O ratio of 7.4 and conductivity of up to 33000 S*cm−1. Based on the data obtained, we have suggested a mechanism of the observed reduction process in terms of the hydrolysis of the glass wafer with subsequent interaction of the leached alkali and alkali earth cations and silicate anions with graphene oxide, resulting in elimination of the oxygen-containing groups from the latter one. The proposed approach can be efficiently used for low-cost bulk-quantity production of graphene and graphene-based materials for a wide field of applications.

Product quality is analyzed for the pipe rolling plant with a continuous mill, and factors affecting product quality indices are established. Engineering conditions are considered providing the required level of metal mechanical properties. Steel melting and extra-furnace technology are adjusted. Heating temperature and deformation regimes during pipe billet and pipe manufacture are proposed. Heat treatment regimes are developed for pipe manufacture in accordance with specified standards.

Heating elements with a resistive layer composed of Si3N4 and 13.5 vol.% ZrC with an average grain size varying from 1 to 46 μm are produced by hot pressing. The phase and grain-size composition and morphology of zirconium carbide grains are examined with X-ray diffraction, sedimentation analysis, and scanning electron microscopy. Microstructural images of the hot-pressed composites are taken with an optical microscope. Direct current resistivity is studied by voltmeter–ammeter method in the temperature range between 20 and 600°C. Different types of structure may form at different dielectric–conductor diameter ratios. These structures considerably differ in resistivity. The resistivity of the composites depends on the specific surface area of the conductive particles and effective cross-sectional area of the conductive cluster (resistivity increases by one order of magnitude with transition from statistical to matrix structure). It is shown that the structure and resistivity can be controlled by introducing a bimodal mixture of coarse and fine conductive particles. The matricity of the composite is evaluated by measuring its resistivity.

Content analysis of mass media publications has become a major scientific method used to analyze public discourse on climate change. We propose a computer-assisted content analysis method to extract prevalent themes and analyze discourse changes over an extended period in an objective and quantifiable manner. The method includes the following: (1) sample selection; (2) preparation of the text segments for computer processing; (3) identifying themes in the texts using exploratory factor analysis; (4) combining identified themes into higher order themes using confirmatory factor analysis; (5) using factor scores to interpret themes obtained from public discourse; and (6) tracking the main themes of public discourse through time. We apply the proposed methodology to the analysis of the articles published in the New York Times on climate change during the period from 1995 to 2010. We found a gradual decline in the volume of material within the “Science” topic and an expansion of themes classified under the “Politics” topic.

Content analysis of newspaper publications has become a major scientific method of the analysis of public discourse. Within the framework of content analysis, we suggest a computer-assisted method to extract the most important topics of this discourse in an objective, quantifiable manner. The method combines frequency and proximity analysis of the text population, selection of the key words, text modification based on a key word dictionary, factor analysis of the modified text population, and factor interpretation. We illustrate the concept by applying the method to study the major topics discussed in the US and UK prestige press that relate to the precautionary principle. Precautionary principle is a concept of preventing environmental damage under scientific uncertainty. The analysis demonstrates the difference between the major topics of the precautionary principle discussion in the US and UK press. In the US, it revolves around an emphasis on the action on global warming, international trade on genetically modified food, environment pollution, the risks of new technologies, and cost-benefit analysis (CBA). In the UK, the major discussion topics include threats to agriculture and farmers, climate change economics, national and EU regulations, and commercial fishing. Other discussion topics, such as health and pollution, water safety regulations, meat safety and trade, and GMO regulations are shared between the countries. The US sample demonstrates more negative views towards the precautionary principle, which is presented as a threat to the US economic interests.

The microwave absorptivity of refractory metallic compounds at 2.45 and 9.53 GHz is studied. It is ascertained that electromagnetic absorption is influenced by the grain size of absorbing particles: when it increases by 10 times, the absorptivity of ZrC, ZrSi2, HƒC, TaN, HƒN, ZrN, and NbC particles becomes higher by a factor of 7 and that of SiC, NbSi2, WC, B4C, MoSi2, and VN particles only by a factor of 2 to 4. It is connected with the physical properties of each compound: magnetic permeability (sign and magnitude), thermal e.m.f. (sign and magnitude), and active ac resistance. It is shown that stoichiometric impurity (namely, the formation of nonmetal vacancies) increases the microwave absorptivity, while the formation of substitution phases does not change the nature of microwave interaction. It is established that the morphology of particles with the same sizes does not influence the microwave absorptivity. It is proved that the measurement of absorption in weak fields can be used for nondestructive examination of refractory metallic compounds.

Farming in higher latitudes is generally believed to benefit from a warmer climate due to extended growing season, reduced risk of frost, availability of more productive cultivars, and an opening potential of farming in northern locations. We analyzed the impact of climate change on production of cereals in Russia and found that this general perception of beneficiary effect of a warmer climate is unlikely to hold, primarily due to increasing risk of droughts in the most important agricultural areas of the country. Past impacts of droughts on food security throughout the twentieth century suggest that a number of adaptation options are available to mitigate the increasing risks of crop failure. We analyze the effectiveness of these measures in connection with a set of climate change projections, under two contrasting scenarios of interregional grain trade: “Fortress Market” and “Open Market.”