Tropical forests provide global climate regulation ecosystem services and their clearing is a significant source of anthropogenic greenhouse gas (GHG) emissions and resultant radiative forcing of ...climate change. However, consensus on pan-tropical forest carbon dynamics is lacking. We present a new estimate that employs recommended good practices to quantify gross tropical forest aboveground carbon (AGC) loss from 2000 to 2012 through the integration of Landsat-derived tree canopy cover, height, intactness and forest cover loss and GLAS-lidar derived forest biomass. An unbiased estimate of forest loss area is produced using a stratified random sample with strata derived from a wall-to-wall 30 m forest cover loss map. Our sample-based results separate the gross loss of forest AGC into losses from natural forests (0.59 PgC yr−1) and losses from managed forests (0.43 PgC yr−1) including plantations, agroforestry systems and subsistence agriculture. Latin America accounts for 43% of gross AGC loss and 54% of natural forest AGC loss, with Brazil experiencing the highest AGC loss for both categories at national scales. We estimate gross tropical forest AGC loss and natural forest loss to account for 11% and 6% of global year 2012 CO2 emissions, respectively. Given recent trends, natural forests will likely constitute an increasingly smaller proportion of tropical forest GHG emissions and of global emissions as fossil fuel consumption increases, with implications for the valuation of co-benefits in tropical forest conservation.
Raman spectra of (NH4)3TiF7 within spectral range 10–3,400 cm−1 at temperatures 8–370 K are recorded, which revealed 2 phase transitions at temperatures T1 = 355 K and T2 = 283 K. First principles ...calculations of lattice dynamics and assignment of the observed lines to specific vibrational types are performed. The first phase transition is classified as an “order–disorder” one. Manifestation of 97 cm−1 vibration (mixed translational NH4 + F7) evidences the creation of the hydrogen bond between ammonium group and free fluorine atom, indicating to reconstructive type of phase transition an T2 = 283 K. The emergence of a large number of vibrational lines in Raman spectra at low temperatures proves symmetry lowering of NH4 tetrahedra with the simultaneous ordering of TiF6 octahedra.
Raman spectroscopy and lattice dynamics simulation has been used to study the phase transitions in ammonium heptafluorotitanate. The first phase transition is accompanied by disordering of TiF6 octahedra and ordering of NH4. The second phase transition determined earlier as a reconstructive one is accompanied by ordering of TiF6 octahedra and a symmetry lowering of NH4 tetrahedra.
The availability of multiple, essentially complete genome sequences of prokaryotes and eukaryotes spurred both the demand and the opportunity for the construction of an evolutionary classification of ...genes from these genomes. Such a classification system based on orthologous relationships between genes appears to be a natural framework for comparative genomics and should facilitate both functional annotation of genomes and large-scale evolutionary studies.
We describe here a major update of the previously developed system for delineation of Clusters of Orthologous Groups of proteins (COGs) from the sequenced genomes of prokaryotes and unicellular eukaryotes and the construction of clusters of predicted orthologs for 7 eukaryotic genomes, which we named KOGs after eukaryotic orthologous groups. The COG collection currently consists of 138,458 proteins, which form 4873 COGs and comprise 75% of the 185,505 (predicted) proteins encoded in 66 genomes of unicellular organisms. The eukaryotic orthologous groups (KOGs) include proteins from 7 eukaryotic genomes: three animals (the nematode Caenorhabditis elegans, the fruit fly Drosophila melanogaster and Homo sapiens), one plant, Arabidopsis thaliana, two fungi (Saccharomyces cerevisiae and Schizosaccharomyces pombe), and the intracellular microsporidian parasite Encephalitozoon cuniculi. The current KOG set consists of 4852 clusters of orthologs, which include 59,838 proteins, or approximately 54% of the analyzed eukaryotic 110,655 gene products. Compared to the coverage of the prokaryotic genomes with COGs, a considerably smaller fraction of eukaryotic genes could be included into the KOGs; addition of new eukaryotic genomes is expected to result in substantial increase in the coverage of eukaryotic genomes with KOGs. Examination of the phyletic patterns of KOGs reveals a conserved core represented in all analyzed species and consisting of approximately 20% of the KOG set. This conserved portion of the KOG set is much greater than the ubiquitous portion of the COG set (approximately 1% of the COGs). In part, this difference is probably due to the small number of included eukaryotic genomes, but it could also reflect the relative compactness of eukaryotes as a clade and the greater evolutionary stability of eukaryotic genomes.
The updated collection of orthologous protein sets for prokaryotes and eukaryotes is expected to be a useful platform for functional annotation of newly sequenced genomes, including those of complex eukaryotes, and genome-wide evolutionary studies.
An experimental laboratory setup combining various gamma spectrometers and neutron generators that is intended for operating at the experimental nuclear-planetology facility deployed at the Joint ...Institute for Nuclear Research (Dubna, Russia) in order to perform physical calibrations of active gamma and neutron spectrometers is described.
In the article questions of mechanical grinding up to nanosize of building powder materials are considered. In the process of mechanoactivation of the composite binder, active molecules of cement ...minerals arise when molecular packets are destroyed in the areas of defects and loosening of the metastable phase during decompensation of intermolecular forces. The process is accompanied by a change in the kinetics of hardening Portland cement. Mechanical processes in the grinding of mineral materials cause, together with an increase in their surface energy, the growth of the isobaric potential of the powders and, accordingly, their chemical activity, which also contributes to high adhesion strength when they come into contact with binders. Thus, a set of measures for mechanical activation allows more fully use the mass of components of the filled cement systems and regulate their properties. At relatively low costs, it is possible to provide an impressive and, importantly, easily repeatable in production conditions result. It is revealed that the use of a vario-planetary mill allows to achieve the best results on grinding the powder building materials.
Sequencing the genomes of multiple, taxonomically diverse eukaryotes enables in-depth comparative-genomic analysis which is expected to help in reconstructing ancestral eukaryotic genomes and major ...events in eukaryotic evolution and in making functional predictions for currently uncharacterized conserved genes.
We examined functional and evolutionary patterns in the recently constructed set of 5,873 clusters of predicted orthologs (eukaryotic orthologous groups or KOGs) from seven eukaryotic genomes: Caenorhabditis elegans, Drosophila melanogaster, Homo sapiens, Arabidopsis thaliana, Saccharomyces cerevisiae, Schizosaccharomyces pombe and Encephalitozoon cuniculi. Conservation of KOGs through the phyletic range of eukaryotes strongly correlates with their functions and with the effect of gene knockout on the organism's viability. The approximately 40% of KOGs that are represented in six or seven species are enriched in proteins responsible for housekeeping functions, particularly translation and RNA processing. These conserved KOGs are often essential for survival and might approximate the minimal set of essential eukaryotic genes. The 131 single-member, pan-eukaryotic KOGs we identified were examined in detail. For around 20 that remained uncharacterized, functions were predicted by in-depth sequence analysis and examination of genomic context. Nearly all these proteins are subunits of known or predicted multiprotein complexes, in agreement with the balance hypothesis of evolution of gene copy number. Other KOGs show a variety of phyletic patterns, which points to major contributions of lineage-specific gene loss and the 'invention' of genes new to eukaryotic evolution. Examination of the sets of KOGs lost in individual lineages reveals co-elimination of functionally connected genes. Parsimonious scenarios of eukaryotic genome evolution and gene sets for ancestral eukaryotic forms were reconstructed. The gene set of the last common ancestor of the crown group consists of 3,413 KOGs and largely includes proteins involved in genome replication and expression, and central metabolism. Only 44% of the KOGs, mostly from the reconstructed gene set of the last common ancestor of the crown group, have detectable homologs in prokaryotes; the remainder apparently evolved via duplication with divergence and invention of new genes.
The KOG analysis reveals a conserved core of largely essential eukaryotic genes as well as major diversification and innovation associated with evolution of eukaryotic genomes. The results provide quantitative support for major trends of eukaryotic evolution noticed previously at the qualitative level and a basis for detailed reconstruction of evolution of eukaryotic genomes and biology of ancestral forms.
Our study considers the structure and tectonics of the Novaya Zemlya archipelago, located in the west Russian Arctic and part of the Eurasian Arctic: (i) the age of the Pre-Paleozoic basement of the ...North block of the archipelago and the geodynamic sedimentation conditions in its northern end, where many kilometers of turbidite sedimentary strata accumulated in the paleobasin during the Late Vendian-Silurian; (ii) the significance of Caledonian tectogenesis in the geological history of the archipelago; (iii) the age and causes of the Late Hercynian (?)-Early Cimmerian orogeny in the Novaya Zemlya archipelago and the relationship of the archipelago structures with the structures of the Urals; (iv) the age and causes for the formation of the modern relief of the Novaya Zemlya archipelago; (v) evidence of active movements of the shelves of the Barents and Kara Seas surrounding Novaya Zemlya. The age of the most ancient rock dating in the area of the Main Novaya Zemlya Fault corresponds to the Vendian (598 ± 26; 609 ± 4 Ma), and the model age of the protolith is estimated at 1 Ga. Two blocks have been established for the Precambrian (North and South) and three, for Middle-Late Paleozoic (North, Central and South). The Middle-Late Paleozoic stage is considered as a reflection of the tectonic-magmatic activation manifested in the Caledonides of Greenland and Scandinavia. The episodes of basic and granitoid magmatism in the intervals of 730–690 and 610–590 Ma indicate the presence of blocks of the former Arctida (?) in the west (Novaya Zemlya), in the central part (Severnaya Zemlya), and in the east (New Siberian Islands and Wrangel Island) of the modern Arctic. Basic areal (plume) magmatism occurred in the Late Devonian, in the Late Permian-Early Triassic and Late Mesozoic. The features of the geological structure of the Novaya Zemlya archipelago strictly correspond to the three orographic areas (tectonic blocks) of the archipelago. The Western and Eastern Novaya Zemlya troughs are the tectonic pairs with the Novaya Zemlya orogen. The heights of the dated sea terraces indicate significant rates of neotectonic uplift of the archipelago.
This paper considers latest highlights in simultaneous and follow-up optical observations of high energy astrophysical phenomena by MASTER Global Robotic Net. Such extreme Universe sources includes ...gamma-ray bursts, gravitational wave events, detected by LIGO/Virgo, fast radio bursts, high energy neutrino sources and others. Some of the neutrinos detected by ground-based facilities owe their births to supermassive black holes – blazars, which are in a special anxious state with high statistical reliability. We discovered the effect of a rapid decrease in the brightness of the blazar PKS 0735+17 at the time of the multiple detection of the high-energy neutrino event IceCube-211208A. This decrease in brightness within several hours was detected with a high confidence (SNR 10) in comparison with a multi-day brightening state of the blazar, which was accompanied not only by a maximum increase in the average brightness, but also by an increase in the amplitude of its brightness fluctuations. Additionally, we analyzed all cases of successful observation of blazars around neutrino events and obtained statistically reliable indications of the relationship between neutrino events and optical activity of blazars in the doubled error box at the 4.2
level.
Differential mobility spectrometry is a powerful tool used in a rapidly growing number and variety of applications for detection and characterization of gas-phase ions. In this paper a comprehensive ...mathematical model of the apparatus implementing the differential mobility spectrometry method is described. For completeness the mathematical theory of the method is provided. The model focuses on the analytical parameters of the differential mobility spectrometry instrument. The influence of instrumental parameters (carrier gas flow rate, separating field amplitude and waveform, filter gap size and geometry) and ion properties (diffusion, mobility and electric field mobility dependence) on the spectral peak characteristics (position, height and width) is examined. Both planar and coaxial instruments are covered in the same mathematical model. The model is extensively validated using published and our own experimental data. Proposed model is demonstrated to be in a good quantitative agreement with experimental data. This model explains all observed phenomena and predicts new ones such as high field focusing.
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