Synergy and Group Size in Microbial Cooperation

Microbes produce many molecules that are important for their growth and development, and the consumption of these secretions by nonproducers has recently become an important paradigm in microbial social evolution. Though the production of these public goods molecules has been studied intensely, little is known of how the benefits accrued and costs incurred depend on the quantity of public good molecules produced. We focus here on the relationship between the shape of the benefit curve and cellular density with a model assuming three types of benefit functions: diminishing, accelerating, and sigmoidal (accelerating then diminishing). We classify the latter two as being synergistic and argue that sigmoidal curves are common in microbial systems. Synergistic benefit curves interact with group sizes to give very different expected evolutionary dynamics. In particular, we show that whether or not and to what extent microbes evolve to produce public goods depends strongly on group size. We show that synergy can create an “evolutionary trap” which can stymie the establishment and maintenance of cooperation. By allowing density dependent regulation of production (quorum sensing), we show how this trap may be avoided. We discuss the implications of our results for experimental design

Heat loss prediction of a confined premixed jet flame using a conjugate heat transfer approach

The presented work addresses the investigation of the heat loss of a confined turbulent jet flame in a lab-scale combustor using a conjugate-heat transfer approach and large-eddy simulation. The analysis includes the assessment of the principal mechanisms of heat transfer in this combustion chamber: radiation, convection and conduction of heat over walls. A staggered approach is used to couple the reactive flow field to the heat conduction through the solid and both domains are solved using two implementations of the same code. Numerical results are compared against experimental data and an assessment of thermal boundary conditions to improve the prediction of the reactive flow field is given.The research leading to these results has received funding through the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme (FP7, 2007–2013) under the Grant agreement No. FP7-290042 for the project COPA-GT as well as the European Union’s Horizon 2020 Programme (2014–2020) and from Brazilian Ministry of Science, Technology and Innovation through Rede Nacional de Pesquisa (RNP) under the HPC4E Project, Grant agreement No. 689772. The authors thankfully acknowledge the computer resources, technical expertise and assistance provided by the Red Española de Supercomputación (RES). Finally, the authors would like to thank O. Lammel for the useful discussions and kindly providing the data for the comparison.Peer ReviewedPostprint (published version

The monomial representations of the Clifford group

We show that the Clifford group - the normaliser of the Weyl-Heisenberg group - can be represented by monomial phase-permutation matrices if and only if the dimension is a square number. This simplifies expressions for SIC vectors, and has other applications to SICs and to Mutually Unbiased Bases. Exact solutions for SICs in dimension 16 are presented for the first time.Comment: Additional author and exact solutions to the SIC problem in dimension 16 adde

FUSE Detection of Galactic OVI Emission in the Halo above the Perseus Arm

Background observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) toward l=95.4, b=36.1 show OVI 1032,1038 in emission. This sight line probes a region of stronger-than-average soft X-ray emission in the direction of high-velocity cloud Complex C above a part of the disk where Halpha filaments rise into the halo. The OVI intensities, 1600+/-300 ph/s/cm^2/sr (1032A) and 800+/-300 ph/s/cm^2/sr (1038A), are the lowest detected in emission in the Milky Way to date. A second sight line nearby (l=99.3, b=43.3) also shows OVI 1032 emission, but with too low a signal-to-noise ratio to obtain reliable measurements. The measured intensities, velocities, and FWHMs of the OVI doublet and the CII* line at 1037A are consistent with a model in which the observed emission is produced in the Galactic halo by hot gas ejected by supernovae in the Perseus arm. An association of the observed gas with Complex C appears unlikely.Comment: accepted for publication in ApJL, 11 pages including 3 figure

Subduction megathrust creep governed by pressure solution and frictional-viscous flow

Subduction megathrust slip speeds range from slow creep at plate convergence rates (centimetres per year) to seismic slip rates (metres per second) in the largest earthquakes on Earth. The deformation mechanisms controlling whether fast slip or slow creep occurs, however, remain unclear. Here, we present evidence that pressure solution creep (fluid-assisted stress driven mass transfer) is an important deformation mechanism in megathrust faults. We quantify megathrust strength using a laboratory-constrained microphysical model for fault friction, involving viscous pressure solution and frictional sliding. We find that at plate-boundary deformation rates, aseismic, frictional–viscous flow is the preferred deformation mechanism at temperatures above 100 °C. The model thus predicts aseismic creep at temperatures much cooler than the onset of crystal plasticity, unless a boundary condition changes. Within this model framework, earthquakes may nucleate when a local increase in strain rate triggers velocity-weakening slip, and we speculate that slip area and event magnitude increase with increasing spacing of strong, topographically derived irregularities in the subduction interface

Biodiversité végétale et vitesse de la régénération de la forêt classée de Sanaimbo (Côte d’Ivoire)

Nous analysons l’impact de l’agriculture traditionnelle sur la diversité végétale dans une forêt semi-décidue afrotropicale non soumise à des perturbations naturelles majeures. Les assemblages d’espèces et les attributs structurels de la diversité sont décrits le long d’une chronoséquence sur 30 ans de champs abandonnés, comparativement aux communautés de forêts « primaires » et de forêts coupées sélectivement. Seulement 6,3% des espèces inventoriées dans les forêts anciennes n’ont pas été observées dans les jachères, alors que 12,3% des espèces sont propres aux jachères. Lorsque la forêt ancienne sur sol ferrallitique est prise comme référence, les analyses de régression linéaire montrent que cette forêt peut recouvrer la structure et la fonction au cours de la quatrième décennie de recolonisation, et la composition spécifique une décennie plus tard. L’invasion précoce des champs par Chromolaena odorata (L.) R. King & H. Robinson. ne semble pas altérer durablement la succession secondaire. Les espèces s’assemblent en communautés végétales discrètes le long du gradient successionnel, en fonction de leurs exigences en lumière, suggérant une partition des niches écologiques.Mots clés : Biodiversité végétale, successions secondaires, indices de diversit

Pre- and post-operative gait analysis for evaluation of neck pain in chronic whiplash

<p>Abstract</p> <p>Introduction</p> <p>Chronic neck pain after whiplash is notoriously refractory to conservative treatment, and positive radiological findings to explain the symptoms are scarce. The apparent disproportionality between subjective complaints and objective findings is significant for the planning of treatment, impairment ratings, and judicial questions on causation. However, failure to identify a symptom's focal origin with routine imaging studies does not invalidate the symptom per se. It is therefore of a general interest both to develop effective therapeutic strategies in chronic whiplash, and to establish techniques for objectively evaluation of treatment outcomes.</p> <p>Methods</p> <p>Twelve patients with chronic neck pain after whiplash underwent pre- and postoperative computerized 3D gait analysis.</p> <p>Results</p> <p>Significant improvement was found in all gait parameters, cervical range-of-motion, and self reported pain (VAS).</p> <p>Conclusion</p> <p>Chronic neck pain is associated with abnormal cervical spine motion and gait patterns. 3D gait analysis is a useful instrument to assess the outcome of treatment for neck pain.</p

Perancangan Corporate Identity PT 21 Express Sebagai Upaya Meningkatkan Brand Awareness

PT. Globalindo 21 Express is one of the shipping service provider with nationwide scale. As a service provider of parcel and document delivery services, PT. 21 Express has a much larger competitors and first foray in this business. Along with the development of the times, the human need to send goods from one place to another place higher. This express PT.21 a forum for addressing the issue. but lately more and more emerging company engaged in the delivery of services to accommodate those needs. Thus it is necessary to have the strength of the company PT.21 express to be able to compete in this global era. The era where business growth faster delivery services are spread all over the country

Global Mangrove Watch:Updated 2010 Mangrove Forest Extent (v2.5)

This study presents an updated global mangrove forest baseline for 2010: Global Mangrove Watch (GMW) v2.5. The previous GMW maps (v2.0) of the mangrove extent are currently considered the most comprehensive available global products, however areas were identified as missing or poorly mapped. Therefore, this study has updated the 2010 baseline map to increase the mapping quality and completeness of the mangrove extent. This revision resulted in an additional 2660 km2 of mangroves being mapped yielding a revised global mangrove extent for 2010 of some 140,260 km2. The overall map accuracy was estimated to be 95.1% with a 95th confidence interval of 93.8–96.5%, as assessed using 50,750 reference points located across 60 globally distributed sites. Of these 60 validation sites, 26 were located in areas that were remapped to produce the v2.5 map and the overall accuracy for these was found to have increased from 82.6% (95th confidence interval: 80.1–84.9) for the v2.0 map to 95.0% (95th confidence interval: 93.7–96.4) for the v2.5 map. Overall, the improved GMW v2.5 map provides a more robust product to support the conservation and sustainable use of mangroves globall