Acoel flatworms are not Platyhelminthes: evidence from phylogenomics

Acoel flatworms are small marine worms traditionally considered to belong to the phylum Platyhelminthes. However, molecular phylogenetic analyses suggest that acoels are not members of Platyhelminthes, but are rather extant members of the earliest diverging Bilateria. This result has been called into question, under suspicions of a long branch attraction (LBA) artefact. Here we re-examine this problem through a phylogenomic approach using 68 different protein-coding genes from the acoel Convoluta pulchra and 51 metazoan species belonging to 15 different phyla. We employ a mixture model, named CAT, previously found to overcome LBA artefacts where classical models fail. Our results unequivocally show that acoels are not part of the classically defined Platyhelminthes, making the latter polyphyletic. Moreover, they indicate a deuterostome affinity for acoels, potentially as a sister group to all deuterostomes, to Xenoturbellida, to Ambulacraria, or even to chordates. However, the weak support found for most deuterostome nodes, together with the very fast evolutionary rate of the acoel Convoluta pulchra, call for more data from slowly evolving acoels (or from its sister-group, the Nemertodermatida) to solve this challenging phylogenetic problem.

HouSI: Heuristic for delimitation of housing submarkets and price homogeneous areas

This paper seeks to address the problem of the empirical identification of housing market segmentation,once we assume that submarkets exist. The typical difficulty in identifying housing submarkets when dealing with many locations is the vast number of potential solutions and, in such cases, the use of the Chow test for hedonic functions is not a practical solution. Here, we solve this problem by undertaking an identification process with a heuristic for spatially constrained clustering, the"Housing Submarket Identifier" (HouSI). The solution is applied to the housing market in the city of Barcelona (Spain), where we estimate a hedonic model for fifty thousand dwellings aggregated into ten groups. In order to determine the utility of the procedure we seek to verify whether the final solution provided by the heuristic is comparable with the division of the city into ten administrative districts.

Complete Analysis of Configuration Rules to Guarantee Reliable Network Security Policies

Peer-reviewed

Pose-based SLAM with probabilistic scan matching algorithm using a mechanical scanned imaging sonar

This paper proposes a pose-based algorithm to solve the full SLAM problem for an autonomous underwater vehicle (AUV), navigating in an unknown and possibly unstructured environment. The technique incorporate probabilistic scan matching with range scans gathered from a mechanical scanning imaging sonar (MSIS) and the robot dead-reckoning displacements estimated from a Doppler velocity log (DVL) and a motion reference unit (MRU). The proposed method utilizes two extended Kalman filters (EKF). The first, estimates the local path travelled by the robot while grabbing the scan as well as its uncertainty and provides position estimates for correcting the distortions that the vehicle motion produces in the acoustic images. The second is an augment state EKF that estimates and keeps the registered scans poses. The raw data from the sensors are processed and fused in-line. No priory structural information or initial pose are considered. The algorithm has been tested on an AUV guided along a 600 m path within a marina environment, showing the viability of the proposed approach

Accounting for adsorption and desorption in Lattice Boltzmann simulations

We report a Lattice-Boltzmann scheme that accounts for adsorption and desorption in the calculation of mesoscale dynamical properties of tracers in media of arbitrary complexity. Lattice Boltzmann simulations made it possible to solve numerically the coupled Navier-Stokes equations of fluid dynamics and Nernst-Planck equations of electrokinetics in complex, heterogeneous media. With the moment propagation scheme, it became possible to extract the effective diffusion and dispersion coefficients of tracers, or solutes, of any charge, e.g., in porous media. Nevertheless, the dynamical properties of tracers depend on the tracer-surface affinity, which is not purely electrostatic and also includes a species-specific contribution. In order to capture this important feature, we introduce specific adsorption and desorption processes in a lattice Boltzmann scheme through a modified moment propagation algorithm, in which tracers may adsorb and desorb from surfaces through kinetic reaction rates. The method is validated on exact results for pure diffusion and diffusion-advection in Poiseuille flows in a simple geometry. We finally illustrate the importance of taking such processes into account in the time-dependent diffusion coefficient in a more complex porous medium.

Use of Bichat"s buccal fat pad for the sealing of orosinusal communications. A presentation of 8 cases

Objectives: To determine the efficacy of the pediculate flap with the buccal fat pad in the sealing of orosinusal communications, describe the surgical technique used, and report the main complications. Patients and method: A retrospective study was made of 8 patients seen in the Service of Oral Surgery of the University of Barcelona Dental Clinic (Spain) for the treatment of orosinusal communications between the years 2007 and 2009. In all cases a pediculate flap with the buccal fat pad was used to solve the problem. Results: All of the orosinusal communications were successfully resolved with this technique. The immediate postoperative complications were pain (37.5%), inflammation (37.5%), edema (32.5%), trismus (37.5%), halitosis (14.3%), suppuration (12.5%) and rhinorrhea (12.5%). Conclusions: The use of Bichat"s buccal fat pad is not regarded as the technique of choice for sealing small to medium sized orosinusal communications. However, in the case of large communications, it is a good option, and the results obtained are optimum.

Shaping urban traffic patterns through congestion charging : What factors drive success or failure?

Congestion costs are emerging as one of the most important challenges faced by metropolitan planners and transport authorities in first world economies. In US these costs were as high as 78 million dollars in 2005 and are growing due to fast increases in travel delays. In order to solve the current and severe levels of congestion the US department of transportation have recently started a program to initiate congestion pricing in five metropolitan areas. In this context it is important to determine those factors helping its implementation and success, but also the problems or difficulties associated with charging projects. In this article we analyze worldwide experiences with urban road charging in order to extract interesting and helpful lessons for policy makers engaged in congestion pricing projects and for those interested in the introduction of traffic management tools to regulate the entrance to big cities.

Motorways, tolls and road safety. Evidence from European Panel Data

The use of tolls is being widespread around the world. Its ability to fund infrastructure projects and to solve budget constraints have been the main rationale behind its renewed interest. However, less attention has been payed to the safety effects derived from this policy in a moment of increasing concern on road fatalities. Pricing best infrastructures shifts some drivers onto worse alternative roads usually not prepared to receive high traffic in comparable safety standards. In this paper we provide evidence of the existence of this perverse consequence by using an international European panel in a two way fixed effects estimation.

Structure and dynamics of the membrane attaching nitric oxide transporter nitrophorin 7

Nitrophorins represent a unique class of heme proteins that are able to perform the delicate transportation and release of the free-radical gaseous messenger nitric oxide (NO) in a pH-triggered manner. Besides its ability to bind to phospholipid membranes, the N-terminus contains an additional Leu-Pro-Gly stretch, which is a unique sequence trait, and the heme cavity is significantly altered with respect to other nitrophorins. These distinctive features encouraged us to solve the X-ray crystallographic structures of NP7 at low and high pH and bound with different heme ligands (nitric oxide, histamine, imidazole). The overall fold of the lipocalin motif is well preserved in the different X-ray structures and resembles the fold of other nitrophorins. However, a chain-like arrangement in the crystal lattice due to a number of head-to-tail electrostatic stabilizing interactions is found in NP7. Furthermore, the X-ray structures also reveal ligand-dependent changes in the orientation of the heme, as well as in specific interactions between the A-B and G-H loops, which are considered to be relevant for the biological function of nitrophorins. Fast and ultrafast laser triggered ligand rebinding experiments demonstrate the pH-dependent ligand migration within the cavities and the exit route. Finally, the topological distribution of pockets located around the heme as well as from inner cavities present at the rear of the protein provides a distinctive feature in NP7, so that while a loop gated exit mechanism to the solvent has been proposed for most nitrophorins, a more complex mechanism that involves several interconnected gas hosting cavities is proposed for NP7.

Domo Hogar, Automatització de l'habitatge

En aquest projecte crearem un sistema per automatitzar els diferents dispositius que podem trobar en una casa. En primer lloc dissenyarem el hardware que serà el sistema nerviós des del que controlarem els dispositius a través del port USB d’un ordinador. Aquest sistema nerviós serà el punt d’interconnexió entre els dispositius de la casa i l’ordinador central que els controlarà. A nivell de hardware, a més a més del mòdul d’entrades i sortides d’interconnexió amb els dispositius que hem esmentat, ens trobem amb la necessitat d’instal•lar un ordinador central i diferents aparells repartits per la casa per poder realitzar les nostres necessitats (accions dels diferents dispositius) des de qualsevol punt de la casa. Amb aquests requeriments haurem d’estudiar les diferents possibilitats per fer el nostre sistema el màxim d’eficaç possible. Finalitzat l’estudi del hardware necessari pel nostre projecte, el següent pas és dissenyar el software. Aquest software serà l’aplicació encarregada de controlar tot el maquinari que hem dissenyat anteriorment i rebrà el nom de DOMO HOGAR. Aquest estarà format per dos programes diferents, DOMO HOGAR SERVER i DOMO HOGAR TERMINAL, cadascun d’ells amb unes funcions específiques. DOMO HOGAR SERVER serà l’aplicació que residirà a l’ordinador central i que permetrà a l’administrador gestionar totes les parts de les que forma part el nostre sistema: dispositius, tasques, pre-condicions, etc... També des d’aquesta aplicació editarem el panell tàctil que mostrarem des dels diferents terminals de l’habitatge. Per últim, aquesta aplicació també s’encarregarà de resoldre les peticions que farem, tant de l’ordinador central com dels terminals, i gestionar les diferents sortides en funció de l’acció a realitzar. Paral•lelament ens trobarem l’aplicació DOMO HOGAR TERMINAL que residirà en cada un dels terminals que hi hagi a la casa. Aquesta aplicació s’inicialitzarà llegint la configuració del panell tàctil de la base de dades de l’aplicació servidor resident a l’ordinador central i reconstruint una rèplica d’aquest panell tàctil. Finalment des d’aquesta aplicació terminal podrem donar ordres que seran emmagatzemades a la llista de tasques pendents de l’ordinador central perquè les resolgui des de l’aplicació del servidor. DOMO HOGAR ha estat creat per facilitar i confortar la vida quotidiana de les persones agilitzant el nostre dia a dia i permetent-nos invertir el nostre temps en les coses realment importants.

Projecte P.I.T.O.S (Projecte d'informació telefònica d'orientació al S.A.T)

JCM és una empresa dedicada al disseny de sistemes de control d’accés. Disposa d’uns equips elèctrics amb molts paràmetres configurables, així es poden utilitzar en molts tipus d’instal•lació. Aquets paràmetres són configurables pels clients. JCM, disposa d’un servei d’atenció telefònica (SAT), que intenta donar solucions a tots els problemes que puguin sorgir als clients. Sovint, no poden donar suport als dubtes dels clients per culpa de la poca informació que reben a través del client. L'objectiu del projecte és resoldre el problema de falta d'informació i mala comunicació per millorar la qualitat del servei que ofereix el SAT. La solució, no ha d’alterar el cost de producció del producte. S’ha de tenir en compte també que els equips poden estar instal•lats en qualsevol part del món i que només es poden utilitzar recursos de fàcil accés per tots els clients. Per complir amb aquests objectius, emetrem un missatge, a través del brunzidor del equip, amb la informació de configuració de l'equip. Aquest missatge viatjarà a través de la xarxa telefònica fins al SAT. Un cop allà, el descodificarem i n'enviarem les dades a un PC perquè pugui presentar les dades sobre la configuració de una forma clara pel SAT.

Experimental analysis of optimization techniques on the road passenger transportation problem

Analyzing the state of the art in a given field in order to tackle a new problem is always a mandatory task. Literature provides surveys based on summaries of previous studies, which are often based on theoretical descriptions of the methods. An engineer, however, requires some evidence from experimental evaluations in order to make the appropriate decision when selecting a technique for a problem. This is what we have done in this paper: experimentally analyzed a set of representative state-of-the-art techniques in the problem we are dealing with, namely, the road passenger transportation problem. This is an optimization problem in which drivers should be assigned to transport services, fulfilling some constraints and minimizing some function cost. The experimental results have provided us with good knowledge of the properties of several methods, such as modeling expressiveness, anytime behavior, computational time, memory requirements, parameters, and free downloadable tools. Based on our experience, we are able to choose a technique to solve our problem. We hope that this analysis is also helpful for other engineers facing a similar problem