Detection of Phase Jumps of Free Core Nutation of the Earth and their Concurrence with Geomagnetic Jerks

We detected phase jumps of the Free Core Nutation (FCN) of the Earth directly from the analysis of the Very Long Baseline Interferometer (VLBI) observation of the Earth rotation for the period 1984-2003 by applying the Weighted Wavelet Z-Transform (WWZ) method and the Short-time Periodogram with the Gabor function (SPG) method. During the period, the FCN had two significant phase jumps in 1992 and 1998. These epochs coincide with the reported occurrence of geomagnetic jerks.Comment: 8 pages, 4 figure

Automated tracking and analysis of centrosomes in early Caenorhabditis elegans embryos

Motivation: The centrosome is a dynamic structure in animal cells that serves as a microtubule organizing center during mitosis and also regulates cell-cycle progression and sets polarity cues. Automated and reliable tracking of centrosomes is essential for genetic screens that study the process of centrosome assembly and maturation in the nematode Caenorhabditis elegans

The genus <i>Elaphomyces </i>(<i>Ascomycota</i>, <i>Eurotiales</i>):a ribosomal DNA-based phylogeny and revised systematics of European 'deer truffles'

Elaphomyces (‘deer truffles’) is one of the most important ectomycorrhizal fungal genera in temperate and subarctic forest ecosystems, but also one of the least documented in public databases. The current systematics are mainly based on macromorphology, and is not significantly different from that proposed by Vittadini (1831). Within the 49 species recognised worldwide, 23 were originally described from Europe and 17 of these were described before the 20th century. Moreover, very recent phylogenetic treatments of the genus are mainly based on a few extra-European species and most common European species are still poorly documented. Based on an extensive taxonomic sampling mainly made in the biogeographically rich Cantabrian area (Spain), complemented with collections from France, Greece, Italy, Norway, Portugal and Sweden, all currently recognized species in Europe have been sequenced at the ITS and 28S of the rDNA. Combined phylogenetic analyses yielded molecular support to sections Elaphomyces and Ceratogaster (here emended), while a third, basal lineage encompasses the sections Malacodermei and Ascoscleroderma as well as the tropical genus Pseudotulostoma. Species limits are discussed and some taxa formerly proposed as genuine species based on morphology and biogeography are re-evaluated as varieties or forms. Spore size and ornamentation, features of the peridial surface, structure of the peridium, and the presence of mycelium patches attached to the peridial surface emerge as the most significant systematic characters. Four new species: E. barrioi, E. quercicola, E. roseolus and E. violaceoniger, one new variety: E. papillatus var. sulphureopallidus, and two new forms: E. granulatus forma pallidosporus and E. anthracinus forma talosporus are introduced, as well as four new combinations in the genus: E. muricatus var. reticulatus, E. muricatus var. variegatus, E. papillatus var. striatosporus and E. morettii var. cantabricus. Lectotypes and epitypes are designated for most recognised species. For systematic purposes, new infrageneric taxa are introduced: E. sect. Ascoscleroderma stat. nov., E. subsect. Sclerodermei stat. nov., E. subsect. Maculati subsect. nov., E. subsect. Muricati subsect. nov., and E. subsect. Papillati subsect. nov. Lastly, E. laevigatus, E. sapidus, E. sulphureopallidus and E. trappei are excluded from the genus and referred to Rhizopogon roseolus, Astraeus sapidus comb. nov., Astraeus hygrometricus and Terfezia trappei comb. nov. (syn.: Terfezia cistophila), respectively

Spatial clustering in the ESO-Sculptor Survey: two-point correlation functions by galaxy type at redshifts 0.1 - 0.5

We calculate the spatial two-point auto and cross-correlation functions for the 765 galaxies with Rc<21.5 and 0.1<z<0.51 in the ESO-Sculptor survey, and explore the segregation effects among the populations of giant (early-type, late spiral) and dwarf (dE, dI) galaxies. At separation of 0.3 h^-1 Mpc, pairs of early-type galaxies dominate the clustering over all the other types of pairs. At intermediate scales, 0.3-5 h^-1 Mpc, mixed pairs of dwarf and giant galaxies contribute equally as pairs of giant galaxies, whereas the latter dominate at ~10 h^-1 Mpc. We detect the signature of the transition between the 1-halo and 2-halo regimes which is expected in the scenario of galaxy formation by hierarchical merging of dark matter halos. The early-type galaxies largely outdo the late spiral galaxies in their 1-halo component, whereas the 2-halo components of both giant populations are comparable. The dwarf galaxies have an intermediate 1-halo component between the 2 giant galaxy types, and their 2-halo component is weak and consistent with null clustering. The present analysis indicates that the early-type galaxies are preferentially located near the centers of the most massive halos, whereas late spiral galaxies tend to occupy their outskirts or the centers of less massive halos. This analysis also unveils new results on the spatial distribution of dwarf galaxies: at the scale at which they significantly cluster inside the halos (<0.3 h^-1 Mpc), they are poorly mixed with the late spiral galaxies, and appear preferentially as satellites of early-type galaxies.Comment: Astronomy & Astrophysics, in press. 29 pages, 15 color figures, 3 table

Mathematical modelling of antimicrobial resistance in agricultural waste highlights importance of gene transfer rate

Antimicrobial resistance is of global concern. Most antimicrobial use is in agriculture; manures and slurry are especially important because they contain a mix of bacteria, including potential pathogens, antimicrobial resistance genes and antimicrobials. In many countries, manures and slurry are stored, especially over winter, before spreading onto fields as organic fertilizer. Thus these are a potential location for gene exchange and selection for resistance. We develop and analyze a mathematical model to quantify the spread of antimicrobial resistance in stored agricultural waste. We use parameters from a slurry tank on a UK dairy farm as an exemplar. We show that the spread of resistance depends in a subtle way on the rates of gene transfer and antibiotic inflow. If the gene transfer rate is high, then its reduction controls resistance, while cutting antibiotic inflow has little impact. If the gene transfer rate is low, then reducing antibiotic inflow controls resistance. Reducing length of storage can also control spread of resistance. Bacterial growth rate, fitness costs of carrying antimicrobial resistance and proportion of resistant bacteria in animal faeces have little impact on spread of resistance. Therefore effective treatment strategies depend critically on knowledge of gene transfer rates

Statistical characteristics of formation and evolution of structure in the universe

An approximate statistical description of the formation and evolution of structure of the universe based on the Zel'dovich theory of gravitational instability is proposed. It is found that the evolution of DM structure shows features of self-similarity and the main structure characteristics can be expressed through the parameters of initial power spectrum and cosmological model. For the CDM-like power spectrum and suitable parameters of the cosmological model the effective matter compression reaches the observed scales $R_{wall}\sim$20 -- 25$h^{-1}$Mpc with the typical mean separation of wall-like elements $D_{SLSS}\sim$50 -- 70$h^{-1}$Mpc. This description can be directly applied to the deep pencil beam galactic surveys and absorption spectra of quasars. For larger 3D catalogs and simulations it can be applied to results obtained with the core-sampling analysis. It is shown that the interaction of large and small scale perturbations modulates the creation rate of early Zel'dovich pancakes and generates bias on the SLSS scale. For suitable parameters of the cosmological model and reheating process this bias can essentially improve the characteristics of simulated structure of the universe. The models with $0.3\leq \Omega_m \leq 0.5$ give the best description of the observed structure parameters. The influence of low mass "warm" dark matter particles, such as a massive neutrino, will extend the acceptable range of $\Omega_m$ and $h$.Comment: 20pages, 7 figures, MNRAS in pres

Comparison between a new multiplex electrochemiluminescence assay and the WHO reference enzyme-linked immunosorbent assay to measure serum antibodies against pneumococcal serotype-specific polysaccharides

BACKGROUND: Two electrochemiluminescence (ECL) assays were developed which, together, can simultaneously measure serum antibodies against pneumococcal capsular polysaccharides (PnPS) for 17 serotypes. The assays were validated for the 13 PnPS included in the 13-valent pneumococcal conjugate vaccine (PCV13). As recommended by the World Health Organization (WHO), we compared the ECL assays with the WHO reference enzyme-linked immunosorbent assay (ELISA) and derived a threshold corresponding to the 0.35 µg/mL threshold established for the WHO reference ELISA for the non-inferiority comparison and licensure of new PCVs against invasive pneumococcal disease. METHODS: A panel of 452 serum samples from children vaccinated with one of the three licensed PCVs was assessed with the ECL assays and the WHO reference ELISA. The ECL assay threshold for the aggregated seven PnPS included in the 7-valent PCV (PCV7) and serotype-specific thresholds were determined using a receiver operating characteristics (ROC) curve-based approach and Deming regression. To evaluate concordance between the ECL assays and the WHO reference ELISA, serostatus agreement rates between both assays and geometric means of the ratios (GMRs) of concentrations obtained with both assays were calculated. RESULTS: The thresholds for the seven aggregated PCV7 serotypes obtained with the ROC curve-based approach and Deming regression approximated 0.35 µg/mL (0.38 and 0.34 µg/mL, respectively). Individual thresholds for the PCV13 serotypes ranged between 0.24 and 0.51 µg/mL across both approaches. Serostatus agreement rates using a 0.35 µg/mL threshold for both assays were ≥86.9% for all PCV13 serotypes. GMRs ranged between 0.85 and 1.25 for 11/13 serotypes and were <1.29 for the two remaining serotypes. CONCLUSION: The ECL assays were comparable to the WHO reference ELISA and offer a sensitive, time- and serum volume-saving method to quantify serotype-specific anti-PnPS antibodies in pediatric sera. A 0.35 µg/mL threshold will be used for each PCV13 serotype to assess PCV immunogenicity in clinical trials