Using Full Information When Computing Modes of Post-Newtonian Waveforms From Inspiralling Compact Binaries in Circular Orbit

The increasing sophistication and accuracy of numerical simulations of compact binaries (especially binary black holes) presents the opportunity to test the regime in which post-Newtonian (PN) predictions for the emitted gravitational waves are accurate. In order to confront numerical results with those of post-Newtonian theory, it is convenient to compare multipolar decompositions of the two waveforms. It is pointed out here that the individual modes can be computed to higher post-Newtonian order by examining the radiative multipole moments of the system, rather than by decomposing the 2.5PN polarization waveforms. In particular, the dominant (l = 2, m = 2) mode can be computed to 3PN order. Individual modes are computed to as high a post-Newtonian order as possible given previous post-Newtonian results.Comment: 15 page

Suspensions of supracolloidal magnetic polymers: self-assembly properties from computer simulations

We study self-assembly in suspensions of supracolloidal polymer-like structures made of crosslinked magnetic particles. Inspired by self-assembly motifs observed for dipolar hard spheres, we focus on four different topologies of the polymer-like structures: linear chains, rings, Y-shaped and X-shaped polymers. We show how the presence of the crosslinkers, the number of beads in the polymer and the magnetic interparticle interaction affect the structure of the suspension. It turns out that for the same set of parameters, the rings are the least active in assembling larger structures, whereas the system of Y- and especially X-like magnetic polymers tend to form very large loose aggregates

土地家屋調査士のための法律学（1） : 土地家屋調査士の業務

１連載開始に際して　　２「弁護士」型業務の獲得　　３認定土地家屋調査士　　４調査士志望者の減

Large-scale distribution of microbial and viral populations in the South Atlantic Ocean

Viruses are abundant, diverse and dynamic compo-nents of the marine environments and play a signi?-cant role in the ocean biogeochemical cycles. Toassess potential variations in the relation betweenviruses and microbes in different geographic regionsand depths, viral and microbial abundance and pro-duction were determined throughout the watercolumn along a latitudinal transect in the South Atlan-tic Ocean. Path analysis was used to examine therelationships between several abiotic and bioticparameters and the different microbial and viral popu-lations distinguished by ?ow cytometry.The depth-integrated contribution of microbial andviral abundance to the total microbial and viralbiomass differed signi?cantly among the differentprovinces. Additionally, the virus-to-microbe ratioincreased with depth and decreased laterally towardsthe more productive regions. Our data revealed thatthe abundance of phytoplankton and microbes is themain controlling factor of the viral populations in theeuphotic and mesopelagic layers, whereas in thebathypelagic realm, viral abundance was only weaklyrelated to the biotic and abiotic variables. The relativecontribution of the three viral populations distin-guished by ?ow cytometry showed a clear geographi-cal pattern throughout the water column, suggestingthat these populations are composed of distinct tax

Advanced interferometric techniques for high resolution bathymetry

International audienceCurrent high-resolution side scan and multibeam sonars produce very large data sets. However, conventional interferometry-based bathymetry algorithms underestimate the potential information of such soundings, generally because they use small baselines to avoid phase ambiguity. Moreover, these algorithms limit the triangulation capabilities of multibeam echosounders to the detection of one sample per beam, i.e., the zero-phase instant. In this paper we argue that the correlation between signals plays a very important role in the exploration of a remotely observed scene. In the case of multibeam sonars, capabilities can be improved by using the interferometric signal as a continuous quantity. This allows consideration of many more useful soundings per beam and enriches understanding of the environment. To this end, continuous interferometry detection is compared here, from a statistical perspective, first with conventional interferometry-based algorithms and then with high-resolution methods, such as the Multiple Signal Classification (MUSIC) algorithm. We demonstrate that a well-designed interferometry algorithm based on a coherence error model and an optimal array configuration permits a reduction in the number of beam formings (and therefore the computational cost) and an improvement in target detection (such as ship mooring cables or masts). A possible interferometry processing algorithm based on the complex correlation between received signals is tested on both sidescan sonars and multibeam echosounders and shows promising results for detection of small in-water targets

Indirect interactions of membrane-adsorbed cylinders

Biological and biomimetic membranes often contain aggregates of embedded or adsorbed macromolecules. In this article, the indirect interactions of cylindrical objects adhering to a planar membrane are considered theoretically. The adhesion of the cylinders causes a local perturbation of the equilibrium membrane shape, which leads to membrane-mediated interactions. For a planar membrane under lateral tension, the interaction is repulsive for a pair of cylinders adhering to the same side of the membrane, and attractive for cylinders adhering at opposite membrane sides. For a membrane in an external harmonic potential, the interaction of adsorbed cylinders is always attractive and increases if forces perpendicular to the membrane act on the cylinders.Comment: 9 pages, 8 figures; typos correcte

Lower prokaryotic leucine incorporation rates under in situ pressure than under decompressed conditions in the deep north Atlantic

Comunicación oralProkaryotic activity and community composition is highly depth-stratified in the oceanic water column reflecting the increasing recalcitrance of dissolved organic matter and decreasing temperature with depth. The role of increasing hydrostatic pressure in controlling deep ocean microbial activity is less well-studied. To determine the influence in hydrostatic pressure on heterotrophic microbial activity, an in situ incubator was deployed in the North Atlantic Ocean at a depth between 500 to 2000 m. The in situ incubator was programmed to collect and incubate prokaryotes under the water after adding 3H-leucine and to fix a certain volume of the incubated samples at specific time intervals (3 to 10 h depending on the depth). Prokaryotic leucine incorporation obtained under in situ pressure conditions was generally lower than that on decompressed samples incubated on board. Ratios of in situ prokaryotic leucine incorporation to decompressed conditions decreased with increasing depth. Our results suggest that bulk heterotrophic prokaryotic production in the deep sea might be lower than expected

Optimal detection of burst events in gravitational wave interferometric observatories

We consider the problem of detecting a burst signal of unknown shape. We introduce a statistic which generalizes the excess power statistic proposed by Flanagan and Hughes and extended by Anderson et al. The statistic we propose is shown to be optimal for arbitrary noise spectral characteristic, under the two hypotheses that the noise is Gaussian, and that the prior for the signal is uniform. The statistic derivation is based on the assumption that a signal affects only affects N samples in the data stream, but that no other information is a priori available, and that the value of the signal at each sample can be arbitrary. We show that the proposed statistic can be implemented combining standard time-series analysis tools which can be efficiently implemented, and the resulting computational cost is still compatible with an on-line analysis of interferometric data. We generalize this version of an excess power statistic to the multiple detector case, also including the effect of correlated noise. We give full details about the implementation of the algorithm, both for the single and the multiple detector case, and we discuss exact and approximate forms, depending on the specific characteristics of the noise and on the assumed length of the burst event. As a example, we show what would be the sensitivity of the network of interferometers to a delta-function burst.Comment: 21 pages, 5 figures in 3 groups. Submitted for publication to Phys.Rev.D. A Mathematica notebook is available at http://www.ligo.caltech.edu/~avicere/nda/burst/Burst.nb which allows to reproduce the numerical results of the pape

A device for assesing microbial activity under ambient hydrostatic pressure: The in situ microbial incubator (ISMI)

Research articleMicrobes in the dark ocean are exposed to hydrostatic pressure increasing with depth. Activity rate measurements and biomass production of dark ocean microbes are, however, almost exclusively performed under atmospheric pressure conditions due to technical constraints of sampling equipment maintaining in situ pressure conditions. To evaluate the microbial activity under in situ hydrostatic pressure, we designed and thoroughly tested an in situ microbial incubator (ISMI). The ISMI allows autonomously collecting and incubating seawater at depth, injection of substrate and fixation of the samples after a preprogramed incubation time. The performance of the ISMI was tested in a high-pressure tank and in several field campaigns under ambient hydrostatic pressure by measuring prokaryotic bulk 3H-leucine incorporation rates. Overall, prokaryotic leucine incorporation rates were lower at in situ pressure conditions than under to depressurized conditions reaching only about 50% of the heterotrophic microbial activity measured under depressurized conditions in bathypelagic waters in the North Atlantic Ocean off the northwestern Iberian Peninsula. Our results show that the ISMI is a valuable tool to reliably determine the metabolic activity of deep-sea microbes at in situ hydrostatic pressure conditions. Hence, we advocate that deep-sea biogeochemical and microbial rate measurements should be performed under in situ pressure conditions to obtain a more realistic view on deep-sea biotic processes.IEO-CSIC, FWF, KAKENHI, ERC and GAI

Changes in bacterial activity and community composition in response to water mass mixing

PosterMixing zones and boundaries between different water masses are "hot spots" of marine biodiversity and activity. We aimed to investigate the effects of water mass mixing in the dark-ocean microbial communities by collecting and incubating natural bacterial communities from the Mediterranean Water (MW; at 1000 m depth), the Subpolar Modal Water (SPMW, 500m) and the Labrador Sea Water (LSW, 1800 m), and comparing them with artificially mixed communities. Mixing experiment 1 consisted of incubating at in sity conditions the original LSW and MW communities, plus a mixture of both (MIX1, dilution 1:1), whereas the Mixing experiment 2 included the original prokaryotic communities from SPMW and MW and a mixture of both (MIX2, dilution 1:1). Bacterial abundance and activity was monitored every 24 h over 8 days, while bacterial community composition and DOM characterization were assessed at the beginning (day 0), middle (day 4) and at the end of the experiment (day 8). Live prokaryotic cell abundance was higher in the MIX1 and MIX2 treatments as compared to the original communities. Moreover, MIX bacteria showed slightly higher leucine incorporation rates than MW or LSW. These metabolic responses were accompanied by changes in the optical properties of DOM, suggesting a change in the dynamics of the organic matter. Taken together, our results indicate differences in the bio-reactvity of the organic matter after mixing as compared to the original water masses that could influence the composition and activity of the bacterial community