Dynamics of Void and its Shape in Redshift Space

We investigate the dynamics of a single spherical void embedded in a Friedmann-Lema\^itre universe, and analyze the void shape in the redshift space. We find that the void in the redshift space appears as an ellipse shape elongated in the direction of the line of sight (i.e., an opposite deformation to the Kaiser effect). Applying this result to observed void candidates at the redshift z~1-2, it may provide us with a new method to evaluate the cosmological parameters, in particular the value of a cosmological constant.Comment: 19 pages, 11 figure

Evaluating the approximation of the affinity laws and improving the efficiency estimate for variable speed pumps

Affinity laws relate to the characteristics of pumps operating at different speeds, and in a water distribution context, are usually used to predict the pump curve of variable speed pumps (VSPs). VSPs can adjust the pump curve to meet the network requirements more efficiently with resultant savings of energy. The estimation of the effectiveness of a VSP is based on hydraulic simulations, in which the behavior of VSPs is described using the affinity laws. The affinity laws, however, contain approximations because they do not take into account factors that do not scale with velocity. In particular, the approximation inherent in the affinity law that computes power and efficiency can produce a misleading result, especially for small-size pumps. The research reported in this paper estimates the error in efficiency for a wide range of pump sizes and tests the use of a previously proposed formula as an alternative to the affinity law. Results show that a better estimation can be achieved for the efficiency of small- and medium-size pumps. Moreover the formula can be easily implemented in hydraulic solvers. © 2013 American Society of Civil Engineers.Angus R. Simpson and Angela March

PHYMYCO-DB: A curated database for analyses of fungal diversity and evolution.

International audienceBackground: In environmental sequencing studies, fungi can be identified based on nucleic acid sequences, using either highly variable sequences as species barcodes or conserved sequences containing a high-quality phylogenetic signal. For the latter, identification relies on phylogenetic analyses and the adoption of the phylogenetic species concept. Such analysis requires that the reference sequences are well identified and deposited in public-access databases. However, many entries in the public sequence databases are problematic in terms of quality and reliability and these data require screening to ensure correct phylogenetic interpretation. Methods and Principal Findings: To facilitate phylogenetic inferences and phylogenetic assignment, we introduce a fungal sequence database. The database PHYMYCO-DB comprises fungal sequences from GenBank that have been filtered to satisfy stringent sequence quality criteria. For the first release, two widely used molecular taxonomic markers were chosen: the nuclear SSU rRNA and EF1-a gene sequences. Following the automatic extraction and filtration, a manual curation is performed to remove problematic sequences while preserving relevant sequences useful for phylogenetic studies. As a result of curation, ,20% of the automatically filtered sequences have been removed from the database. To demonstrate how PHYMYCO-DB can be employed, we test a set of environmental Chytridiomycota sequences obtained from deep sea samples. Conclusion: PHYMYCO-DB offers the tools necessary to: (i) extract high quality fungal sequences for each of the 5 fungal phyla, at all taxonomic levels, (ii) extract already performed alignments, to act as 'reference alignments', (iii) launch alignments of personal sequences along with stored data. A total of 9120 SSU rRNA and 672 EF1-a high-quality fungal sequences are now available. The PHYMYCO-DB is accessible through the URL http://phymycodb.genouest.org/

Selection and characterization of the probiotic potential of some lactic acid bacteria isolated from infant feces

Abstrac

Redshift of the Einstein Ring in MG1549+305

A deep spectrum taken with the Echelle Spectrograph and Imager (ESI) at the Keck II Telescope as part of the Lenses Structure and Dynamics (LSD) Survey reveals the redshifts of the extremely red source of the radio Einstein Ring in the gravitational lens system MG1549+305 ($z_{\rm s}=1.170\pm 0.001$) and an intermediate redshift lensed spiral galaxy ($z_{\rm G2}=0.604\pm 0.001$). The source redshift allows us to determine the mass of the SB0 lens galaxy enclosed by the Einstein Radius (R_{\rm E}=1\farcs15\pm0\farcs05) $M_{\rm E}$$\equiv$$M(<R_{\rm E}) = 8.4\pm0.7\times 10^{10} h_{65}^{-1}$ M$_\odot$. This corresponds to a Singular Isothermal Ellipsoid (SIE) velocity dispersion $\sigma_{\rm SIE}=214\pm5$ \kms, in good agreement with the measured stellar velocity dispersion $\sigma=227\pm18$ \kms (Leh\'ar et al. 1996). The mass-to-light ratio within the Einstein Radius ($\sim$1.4 effective radii) is $10\pm1 h_{65}$ \mlu. This is only marginally larger than typical stellar mass-to-light ratios of local early-type galaxies, indicating that dark matter is not likely to be dominant inside the Einstein Radius.Comment: 4 pages, 3 figures, accepted for publication in MNRA

Single-objective versus multiobjective optimization of water distribution systems accounting for greenhouse gas emissions by carbon pricing

Previous research has demonstrated that there are significant trade-offs between the competing objectives of minimizing costs and greenhouse gas (GHG) emissions for water distribution system (WDS) optimization. However, upon introduction of an emission trading scheme, GHG emissions are likely to be priced at a particular level. Thus, a monetary value can be assigned to GHG emissions, enabling a single-objective optimization approach to be used. This raises the question of whether the introduction of carbon pricing under an emission trading scheme will make the use of a multiobjective optimization approach obsolete or whether such an approach can provide additional insights that are useful in a decision-making context. In this paper, the above questions are explored via two case studies. The optimization results obtained for the two case studies using both single-objective and multiobjective approaches are analyzed. The analyses show that the single-objective approach results in a loss of trade-off information between the two objectives. In contrast, the multiobjective approach provides decision makers with more insight into the trade-offs between the two objectives. As a result, a multiobjective approach is recommended for the optimization of WDSs accounting for GHG emissions when considering carbon pricing. © 2010 ASCE.Wenyan Wu, Holger R. Maier, and Angus R. Simpso

The amplitude of mass fluctuations and mass density of the Universe constrained by strong gravitational lensing

We investigate the linear amplitude of mass fluctuations in the universe, $\sigma_8$, and the present mass density parameter of the Universe, $\Omega_\mathrm{m}$, from the statistical strong gravitational lensing. We use the two populations of lens halos model with fixed cooling mass scale M_\mathrm{c}=3\times 10^{13}h^{-1}M_{\sun} to match the observed lensing probabilities, and leave $\sigma_8$ or $\Omega_\mathrm{m}$ as a free parameter to be constrained by data. Another varying parameter is the equation of state of dark energy $\omega$, and its typical values of -1, -2/3, -1/2 and -1/3 are investigated. We find that $\sigma_8$ is degenerate with $\Omega_\mathrm{m}$ in a way similar to that suggested by present day cluster abundance as well as cosmic shear lensing measurements: $\sigma_8\Omega_\mathrm{m}^{0.6}\approx 0.33$ (Bahcall & Bode\cite{bahcall03a} and references therein). However, both $\sigma_8\leq 0.7$ and $\Omega_\mathrm{m}\leq 0.2$ can be safely ruled out, the best value is when $\sigma_8=1.0$, $\Omega_\mathrm{m}=0.3$ and $\omega=-1$. This result is different from that obtained by Bahcall & Bode (\cite{bahcall03a}), who gives $\sigma_8 =0.98\pm 0.1$ and $\Omega_m =0.17\pm 0.05$. For $\sigma_8=1.0$, higher value of $\Omega_\mathrm{m}=0.35$ requires $\omega=-2/3$ and $\Omega_\mathrm{m}=0.40$ requires $\omega=-1/2$.Comment: 9 pages, 4 figures, references update

К проблеме социальной эффективности инноваций в профессиональном образовании

Movile Cave, Romania, is an unusual underground ecosystem that has been sealed off from the outside world for several million years and is sustained by non-phototrophic carbon fixation. Methane and sulfur-oxidising bacteria are the main primary producers, supporting a complex food web that includes bacteria, fungi and cave-adapted invertebrates. A range of methylotrophic bacteria in Movile Cave grow on one-carbon compounds including methylated amines, which are produced via decomposition of organic-rich microbial mats. The role of methylated amines as a carbon and nitrogen source for bacteria in Movile Cave was investigated using a combination of cultivation studies and DNA stable isotope probing (DNA-SIP) using 13C-monomethylamine (MMA). Two newly developed primer sets targeting the gene for gamma-glutamylmethylamide synthetase (gmaS), the first enzyme of the recently-discovered indirect MMA-oxidation pathway, were applied in functional gene probing. SIP experiments revealed that the obligate methylotroph Methylotenera mobilis is one of the dominant MMA utilisers in the cave. DNA-SIP experiments also showed that a new facultative methylotroph isolated in this study, Catellibacterium sp. LW-1 is probably one of the most active MMA utilisers in Movile Cave. Methylated amines were also used as a nitrogen source by a wide range of non-methylotrophic bacteria in Movile Cave. PCR-based screening of bacterial isolates suggested that the indirect MMA-oxidation pathway involving GMA and N-methylglutamate is widespread among both methylotrophic and non-methylotrophic MMA utilisers from the cave