Microsatellites reveal high population viscosity and limited dispersal in the ant Formica paralugubris

We used microsatellites to study the fine-scale genetic structure of a highly polygynous and largely uni-colonial population of the ant Formica paralugubris. Genetic data indicate that long-distance gene flow between established nests is limited and new queens are primarily recruited from within their natal nest. Most matings occur between nestmates and are random at this level. In the center of the study area, budding and permanent connections between nests result in strong population viscosity, with close nests being more similar generically than distant nests. In contrast, nests located outside of this supercolony show no isolation by distance, suggesting that they have been initiated by queens that participated in mating flights rather than by budding from nearby nests in our sample population. Recruitment of nestmates as new reproductive individuals and population viscosity in the supercolony increase genetic differentiation between nests. This in turn inflates relatedness estimates among worker nestmates (r = 0.17) above what is due to close pedigree links. Local spatial genetic differentiation may favor the maintenance of altruism when workers raise queens that will disperse on foot and compete with less related queens from neighboring nests or disperse on the wing and compete with unrelated queens.

The place preference task: a new tool for studying the relation between behavior and place cell activity in rats

This study describes a task that combines random searching with goal directed navigation. The testing was conducted on a circular elevated open field (80 cm in diameter), with an unmarked target area (20 cm in diameter) in the center of 1 of the 4 quadrants. Whenever the rat entered the target area, the computerized tracking system released a pellet to a random point on the open field. Rats were able to learn the task under light and in total darkness, and on a stable or a rotating arena. Visual information was important in light, but idiothetic information became crucial in darkness. Learning of a new position was quicker under light than in total darkness on a rotating arena. The place preference task should make it possible to study place cells (PCs) when the rats use an allothetic (room frame) or idiothetic (arena frame) representation of space and to compare the behavioral response with the PCs' activity.

A pseudo-spectral method for the simulation of poro-elastic seismic wave propagation in 2D polar coordinates using domain decomposition

We present a novel numerical approach for the comprehensive, flexible, and accurate simulation of poro-elastic wave propagation in 2D polar coordinates. An important application of this method and its extensions will be the modeling of complex seismic wave phenomena in fluid-filled boreholes, which represents a major, and as of yet largely unresolved, computational problem in exploration geophysics. In view of this, we consider a numerical mesh, which can be arbitrarily heterogeneous, consisting of two or more concentric rings representing the fluid in the center and the surrounding porous medium. The spatial discretization is based on a Chebyshev expansion in the radial direction and a Fourier expansion in the azimuthal direction and a Runge-Kutta integration scheme for the time evolution. A domain decomposition method is used to match the fluid-solid boundary conditions based on the method of characteristics. This multi-domain approach allows for significant reductions of the number of grid points in the azimuthal direction for the inner grid domain and thus for corresponding increases of the time step and enhancements of computational efficiency. The viability and accuracy of the proposed method has been rigorously tested and verified through comparisons with analytical solutions as well as with the results obtained with a corresponding, previously published, and independently bench-marked solution for 2D Cartesian coordinates. Finally, the proposed numerical solution also satisfies the reciprocity theorem, which indicates that the inherent singularity associated with the origin of the polar coordinate system is adequately handled.

The benefits of limited feedback in organizations

In most firms, managers periodically assess workers' performance. Evidence suggeststhat managers withhold information during these reviews, and some observersargue that this necessarily reduces surplus. This paper assesses the validity of thisargument when workers have career concerns. Disclosure has two effects: it exposesthe worker to uncertainty about future effort levels, but allows him to use current effortto influence his employer's beliefs about future effort. The surplus-maximizingdisclosure policy reveals output realizations in the center of the distribution, butnot in the tails. Thus, it is efficient for firms to reveal some but not all performanceinformation.

Geometry, petrology and growth of a shallow crustal laccolith : the Torres del Paine Mafic Complex (Patagonia)

1. ABSTRACTS - RÉSUMÉSSCIENTIFIC ABSTRACT - ENGLISH VERSIONGeometry, petrology and growth of a shallow crustal laccolith: the Torres del Paine Mafi c Complex (Patagonia)The Torres del Paine intrusive complex (TPIC) is a composite mafic-granitic intrusion, ~70km2, belonging to a chain of isolated Miocene plutons in southern Patagonia. Their position is intermediate between the Mesozoic-Cenozoic calc-alkaline subduction related Patagonian batholith in the West and the late Cenozoic alkaline basaltic back-arc related plateau lavas in the East. The Torres del Paine complex formed during an important reconfiguration of the Patagonian geodynamic setting, with a migration of magmatism from the arc to the back-arc, possibly related to the Chile ridge subductionThe complex intruded the flysch of the Cretaceous Cerro Toro and Punta Barrosa Formations during the Miocene, creating a well-defined narrow contact aureole of 200-400 m width.In its eastern part, the Torres del Paine intrusive complex is a laccolith, composed of a succession of hornblende-gabbro to diorite sills at its base, with a total thickness of ~250m, showing brittle contacts with the overlying granitic sills, that form spectacular cliffs of more than 1000m. This laccolith is connected, in the western part, to its feeding system, with vertical alternating sheets of layered gabbronorite and Hbl-gabbro, surrounded and percolated by diorites. ID-TIMS U-Pb on zircons on feeder zone (FZ) gab- bros yield 12.593±0.009Ma and 12.587±0.009Ma, which is identifcal within error to the oldest granite dated so far by Michel et al. (2008). In contrast, the laccolith mafic complex is younger than than the youngest granite (12.50±0.02Ma), and has been emplaced from 12.472±0.009Ma to 12.431 ±0.006Ma, by under-accretion beneath the youngest granite at the interface with previously emplaced mafic sills.The gabbronorite crystallization sequence in the feeder zone is dominated by olivine, plagioclase, clinopyroxene and orthopyroxene, while amphibole forms late interstitial crystals. The crystallization sequence is identical in Hornblende-gabbro from the feeder zone, with higher modal hornblende. Gabbronorite and Hornblende-gabbro both display distinct Eu and Sr positive anomalies. In the laccolith, a lower Hornblende-gabbro crystallized in sills and evolved to a high alkali shoshonitic series. The Al203, Ti02, Na20, K20, Ba and Sr composition of these gabbros is highly variable and increases up to ~50wt% Si02. The lower hornblende-gabbro is characterized by kaersutite anhedral cores with inclusions of olivine, clino- and orthopyroxene and rare apatite and An70 plagioclase. Trace element modelling indicates that hornblende and clinopyroxene are in equilibrium with a liquid whose composition is similar to late basaltic trachyandesitic dikes that cut the complex. The matrix in the lower hornblende gabbro is composed of normally zoned oligoclase, Magnesio-hornblende, biotite, ilmenite and rare quartz and potassium feldspar. This assemblage crystallized in-situ from a Ba and Sr-depleted melts. In contrast, the upper Hbl-gabbro is high-K calc-alkaline. Poikilitic pargasite cores have inclusions of euhedral An70 plagioclase inclusions, and contain occasionally clinopyroxene, olivine and orthopyroxene. The matrix composition is identical to the lower hornblende-gabbro and similar to the diorite. Diorite bulk rock compositions show the same mineralogy but different modal proportions relative to hornblende-gabbrosThe Torres del Paine Intrusive Complex isotopic composition is 87Sr/86Sr=0.704, 143Nd/144Nd=0.5127, 206Pb/204Pb=18.70 and 207Pb/204Pb=15.65. Differentiated dioritic and granitic units may be linked to the gabbroic cumulates series, with 20-50% trapped interstitial melt, through fractionation of olivine-bearing gabbronorite or hornblende-gabbro fractionation The relative homogeneity of the isotopic compositions indicate that only small amounts of assimilation occurred. Two-pyroxenes thermometry, clinopyroxene barometry and amphibole-plagioclase thermometry was used to estimate pressure and temperature conditions. The early fractionation of ultramafic cumulates occurs at mid to lower crustal conditions, at temperatures exceeding 900°C. In contrast, the TPIC emplacement conditions have been estimated to ~0.7±0.5kbar and 790±60°C.Based on field and microtextural observations and geochemical modelling, fractionation of basaltic-trachyandesitic liquids at intermediate to lower crustal levels, has led to the formation of the Torres del Paine granites. Repetitive replenishment of basaltic trachy- andesitic liquid in crustal reservoirs led to mixed magmas that will ascend via the feeder zone, and crystallize into a laccolith, in the form of successive dioritic and gabbroic sills. Dynamic fractionation during emplacement concentrated hornblende rich cumulates in the center of individual sills. Variable degrees.of post-emplacement compaction led to the expulsion of felsic liquids that preferentially concentrated at the top of the sills. Incremental sills amalgamation of the entire Torres del Paine Intrusive Complex has lasted for ~160ka.RESUME SCIENTIFIQUE - VERSION FRANÇAISEGéométrie, pétrologie et croissance d'un laccolite peu profond : Le complexe ma- fique du Torres del Paine (Patagonie)Le Complexe Intrusif du Torres del Paine (CITP) est une intrusion bimodale, d'environ 70km2, appartenant à une chaîne de plutons Miocènes isolés, dans le sud de la Patago-nie. Leur position est intermédiaire entre le batholite patagonien calco-alcalin, à l'Ouest, mis en place au Mesozoïque-Cenozoïque dans un contexte de subduction, et les basal-tes andésitiques et trachybasaltes alcalins de plateau, plus jeune, à l'Est, lié à l'ouverture d'un arrière-arc.A son extrémité Est, le CITP est une succession de sills de gabbro à Hbl et de diorite, sur une épaisseur de ~250m, avec des évidences de mélange. Les contacts avec les sills de granite au-dessus, formant des parois de plus de 1000m, sont cassants. Ce laccolite est connecté, dans sa partie Ouest, à une zone d'alimentation, avec des intrusions sub-ver- ticales de gabbronorite litée et de gabbro à Hbl, en alternance. Celles-ci sont traversées et entourées par des diorites. Les zircons des gabbros de la zone d'alimentation, datés par ID-TIMS, ont cristallisés à 12.593±0.009Ma et 12.587±0.009Ma, ce qui correspond au plus vieux granite daté à ce jour par Michel et al. (2008). A l'inverse, les roches manques du laccolite se sont mises en place entre 12.472±0.009Ma et 12.431 ±0.006Ma, par sous-plaquage successifs à l'interface avec le granite le plus jeune daté à ce jour (12.50±0.02Ma).La séquence de cristallisation des gabbronorites est dominée par Ol, Plg, Cpx et Opx, alors que la Hbl est un cristal interstitiel. Elle est identique dans les gabbros à Hbl de la zone d'alimentation, avec ~30%vol de Hbl. Les gabbros de la zone d'alimentation montrent des anomalies positives en Eu et Sr distinctes. Dans le laccolite, le gabbro à Hbl inférieur évolue le long d'une série shoshonitique, riche en éléments incompatibles. Sa concentration en Al203, Ti02, Na20, K20, Ba et Sr est très variable et augmente rapide-ment jusqu'à ~50wt% Si02. Il est caractérisé par la présence de coeurs résorbés de kaer- sutite, entourés de Bt, et contenant des inclusions d'OI, Cpx et Opx, ou alors d'Ap et de rares Plg (An70). Hbl et Cpx ont cristallisés à partir d'un liquide de composition similaire aux dykes trachy-andesite basaltique du CITP. La matrice, cristallisée in-situ à partir d'un liquide pauvre en Ba et Sr, est composée d'oligoclase zoné de façon simple, de Mg-Hbl, Bt, llm ainsi que de rares Qtz et KF. Le gabbro à Hbl supérieur, quant à lui, appartient à une suite chimique calco-alcaline riche en K. Des coeurs poecilitiques de pargasite con-tiennent de nombreuses inclusions de Plg (An70) automorphe, ainsi que des Ol, Cpx et Opx. La composition de la matrice est identique à celle des gabbros à Hbl inférieurs et toutes deux sont similaires à la minéralogie des diorites. Les analyses sur roches totales de diorites montrent la même variabilité que celles de gabbros à Hbl, mais avec une ten-eur en Si02 plus élevée.La composition isotopique des liquides primitifs du CITP a été mesurée à 87Sr/86Sr=0.704, 143Nd/144Nd=0.5127, 206Pb/204Pb=18.70 et 207Pb/204Pb=15.65. Les granites et diorites différenciés peuvent être reliés à des cumulais gabbronoritiques (F=0.74 pour les granites et F=1-0.5 pour les diorites) et gabbroïques à Hbl (fractionnement supplémentaire pour les granites, avec F=0.3). La cristallisation de 20 à 50%vol de liquide interstitiel piégé dans les gabbros du CITP explique leur signature géochimique. Seules de faibles quantités de croûte continentale ont été assimilées. La température et la pression de fractionnement ont été estimées, sur la base des thermobaromètres Opx-Cpx, Hbl-Plg et Cpx, à plus de 900°C et une profondeur correspondant à la croûte inférieure-moyenne. A l'inverse, les conditions de cristallisation de la matrice des gabbros et diorites du laccolite ont été estimées à 790±60°C et ~0.7±0.5kbar.Je propose que les liquides felsiques du CITP se soient formés par cristallisation frac-tionnée en profondeur des assemblages minéralogiques observés dans les gabbros du CITP, à partir d'un liquide trachy-andesite basaltique. La percolation de magma dans les cristaux accumulés permet la remontée du mélange à travers la zone d'alimentation, vers le laccolite, où des sills se mettent en place successivement. L'amalgamation de sills dans le CITP a duré ~160ka.Le CITP s'est formé durant une reconfiguration importante du contexte géodynamique en Patagonie, avec un changement du magmatisme d'arc vers un volcanisme d'arrière- arc. Ce changement est certainement lié à la subduction de la ride du Chili.RESUME GRAND PUBLIC - VERSION FRANÇAISEGéométrie, pétrologie et croissance d'une chambre magmatique peu profonde : Le complexe mafique du Torres del Paine (Patagonie)Le pourtour de l'Océan Pacifique est caractérisé par une zone de convergence de plaques tectoniques, appelée zone de subduction, avec le plongement de croûte océa-nique sous les Andes dans le cas de la Patagonie. De nombreux volcans y sont associés, formant la ceinture de feu. Mais seuls quelques pourcents de tout le magma traversant la croûte terrestre parviennent à la surface et la majeure partie cristallise en profondeur, dans des chambres magmatiques. Quelles est leur forme, croissance, cristallisation et durée de vie ? Le complexe magmatique du Torres del Paine représente l'un des meilleurs endroits au monde pour répondre à ces questions. Il se situe au sud de la Patagonie, formant un massif de 70km2. Des réponses peuvent être trouvées à différentes échelles, variant de la montagne à des minéraux de quelques 1000ème de millimètres.Il est possible de distinguer trois types de roches : des gabbros et des diorites sur une épaisseur de 250m, surmontées par des parois de granite de plus de 1000m. Les contacts entre ces roches sont tous horizontaux. Entre granites et gabbro-diorite, le contact est net, indiquant que le second magma s'est mis en place au contact avec un magma plus ancien, totalement solidifié. Entre gabbros et diorites, les contacts sont diffus, souvent non-linéaires, indiquant à l'inverse la mise en contact de magmas encore partiellement liquides. Dans la partie Ouest de cette chambre magmatique, les contacts entre roches sont verticaux. Il s'agit certainement du lieu de remplissage de la chambre magmatique.Lors du refroidissement d'un magma, différents cristaux vont se former. Leur stabilité et leur composition varient en fonction de la pression, de la température ou de la chimie du magma. La séquence de cristallisation peut être définie sur la base d'observations microscopiques et de la composition chimique des minéraux. Différents gabbros sont ainsi distingués : le gabbro à la base est riche en hornblende, d'une taille de ~5mm, sans inclusion de plagioclase mais avec des cristaux d'olivine, clinopyroxene et orthopyroxene inclus ; le gabbro supérieur est lui-aussi riche en hornblende (~5mm), avec les mêmes inclusions additionnées de plagioclase. Ces cristaux se sont formés à une température supérieure à 900°C et une profondeur correspondant à la croûte moyenne ou inférieure. Les minéraux plus fin, se trouvant hors des cristaux de hornblende des deux gabbros, sont similaires à ceux des diorites : plagioclase, biotite, hornblende, apatite, quartz et feldspath alcalin. Ces minéraux sont caractéristiques des granites. Ils ont cristallisé à ~790°C et ~2km de profondeur.La cristallisation des minéraux et leur extraction du magma par gravité provoque un changement progressif de la composition de ce dernier. Ainsi, après extraction d'olivine et d'orthopyroxene riches en Mg, de clinopyroxene riche en Ca, de plagioclase riche en Ca et Al et d'hornblende riche en Ca, Al et Mg, le liquide final sera appauvri en ces élé-ments. Un lien peut ainsi être proposé entre les diorites dont la composition est proche du liquide de départ, les granites dont la composition est similaire au liquide final, et les gabbros dont la minéralogie correspond aux minéraux extraits.L'utilisation de zircons, un minéral riche en U dont les atomes se transforment en Pb par décomposition radioactive au cours de millions d'années, permet de dater le refroidissement des roches qui les contiennent. Ainsi, il a été observé que les roches de la zone d'alimentation, à l'Ouest du complexe magmatique, ont cristallisés il y a 12.59±0.01 Ma, en même temps que les granites les plus vieux, se trouvant au sommet de la chambre magmatique, datés par Michel et al. (2008). Les deux roches pourraient donc avoir la même origine. A l'inverse, les gabbros et diorites de la chambre magmatique ont cristallisé entre 12.47±0.01Ma et 12.43±0.01Ma, les roches les plus vieilles étant à la base.En comparant la composition des roches du Torres del Paine avec celles d'autres en-tités géologiques de Patagonie, les causes du magmatisme peuvent être recherchées. A l'Ouest, on trouve en effet des intrusions granitiques, plus anciennes, caractéristiques de zones de convergence de plaque tectonique, alors qu'à l'Est, des laves basaltiques plus jeunes sont caractéristiques d'une dynamique d'extension. Sur la base des compositions chimiques des roches de ces différentes entités, l'évolution progressive de l'une à l'autre a pu être démontrée. Elle est certainement due à l'arrivée d'une dorsale océanique (zone d'extension crustale et de création de croûte océanique par la remontée de magma) dans la zone de subduction, le long des Andes.Je propose que, dans un premier temps, des magmas granitiques sont remontés dans la chambre magmatique, laissant d'importants volumes de cristaux dans la croûte pro-fonde. Dans un second épisode, les cristaux formés en profondeur ont été transportés à travers la croûte continentale, suite au mélange avec un nouveau magma injecté. Ces magmas chargés de cristaux ont traversé la zone d'alimentation avant de s'injecter dans la chambre magmatique. Différents puises ont été distingués, injectés dans la chambre magmatique du sommet à la base concernant les granites, puis à la base du granite le plus jeune pour les gabbros et diorites. Le complexe magmatique du Torres del Paine s'est construit sur une période totale de 160'000±20'000 ans.

The left-right dimension in Latin America

We present voters' self-placement and 68 political party locations on the left-right dimension in 17 Latin American countries. Innovative calculations are based on data from Latinobarometer annual surveys from 1995 to 2002. Our preliminary analysis of the results suggests that most Latin American voters are relatively highly ideological and rather consistently located on the left-right dimension, but they have very high levels of political alienation regarding the party system. Both voters' self-placement and the corresponding party locations are presently highly polarized between the center and the right, with a significant weakness of leftist or broadly appealing 'populist' positions.

Orientation Center Newsletter, Vol. 28, no. 1, Summer 2008

The Orientation Center newsletter is produced three times a year, and includes articles written by students, staff, and former students. It also contains news about what is happening to other students who have been in the Center.

Constant fluctuating asymmetry but not directional asymmetry along the geographic distribution of Drosophila antonietae (Diptera, Drosophilidae)

ABSTRACT The population dynamics of a species tends to change from the core to the periphery of its distribution. Therefore, one could expect peripheral populations to be subject to a higher level of stress than more central populations (the center–periphery hypothesis) and consequently should present a higher level of fluctuating asymmetry. To test these predictions we study asymmetry in wing shape of five populations of Drosophila antonietae collected throughout the distribution of the species using fluctuating asymmetry as a proxy for developmental instability. More specifically, we addressed the following questions: (1) what types of asymmetry occur in populations of D. antonietae? (2) Does the level of fluctuating asymmetry vary among populations? (3) Does peripheral populations have a higher fluctuating asymmetry level than central populations? We used 12 anatomical landmarks to quantify patterns of asymmetry in wing shape in five populations of D. antonietae within the framework of geometric morphometrics. Net asymmetry – a composite measure of directional asymmetry + fluctuating asymmetry – varied significantly among populations. However, once net asymmetry of each population is decomposed into directional asymmetry and fluctuating asymmetry, most of the variation in asymmetry was explained by directional asymmetry alone, suggesting that populations of D. antonietae have the same magnitude of fluctuating asymmetry throughout the geographical distribution of the species. We hypothesize that larval development in rotting cladodes might play an important role in explaining our results. In addition, our study underscores the importance of understanding the interplay between the biology of a species and its geographical patterns of asymmetry.

Orientation Center Newsletter, Vol. 28, no. 2, November-December 2008

The Orientation Center newsletter is produced three times a year, and includes articles written by students, staff, and former students. It also contains news about what is happening to other students who have been in the Center.

Anomalous Proper-Motions in the Cygnus Super Bubble Region

In an analysis of proper motions of O and B stars contained the Input Catalogue for Hipparcos, we have found a clear deviation from the expected pattern of systematic motions which can be readily identified with the associations Cygnus OB1 and Cygnus OB9, located near de the edge of the Cygnus Superbubble. Teha anomalous motions are directed outwards from the center of the Superbubble, which is coincident with tha association Cygnus OB2. This seems to support the hypothesis of a strong stellar and supernova activity in Cygnus 0B2 giving rise to the Superbubble and, by means of gravitational instabilities in its boundaries, to Cygnus 0B1 and Cygnus OB9. New uvby-beta aperture photometry of selected O and B stars in the area of Cygnus OB1 and Cygnus OB9 is also presented and analyzed in this paper.

Measurements of the bulk and interfacial velocity profiles in oscillating Newtonian and Maxwellian fluids

We present the dynamic velocity profiles of a Newtonian fluid (glycerol) and a viscoelastic Maxwell fluid (CPyCl-NaSal in water) driven by an oscillating pressure gradient in a vertical cylindrical pipe. The frequency range explored has been chosen to include the first three resonance peaks of the dynamic permeability of the viscoelastic-fluid¿pipe system. Three different optical measurement techniques have been employed. Laser Doppler anemometry has been used to measure the magnitude of the velocity at the center of the liquid column. Particle image velocimetry and optical deflectometry are used to determine the velocity profiles at the bulk of the liquid column and at the liquid-air interface respectively. The velocity measurements in the bulk are in good agreement with the theoretical predictions of a linear theory. The results, however, show dramatic differences in the dynamic behavior of Newtonian and viscoelastic fluids, and demonstrate the importance of resonance phenomena in viscoelastic fluid flows, biofluids in particular, in confined geometries.

Retrospective feasibility study of simultaneous integrated boost in cervical cancer using Tomotherapy: the impact of organ motion and tumor regression.

BACKGROUND: Whole pelvis intensity modulated radiotherapy (IMRT) is increasingly being used to treat cervical cancer aiming to reduce side effects. Encouraged by this, some groups have proposed the use of simultaneous integrated boost (SIB) to target the tumor, either to get a higher tumoricidal effect or to replace brachytherapy. Nevertheless, physiological organ movement and rapid tumor regression throughout treatment might substantially reduce any benefit of this approach. PURPOSE: To evaluate the clinical target volume - simultaneous integrated boost (CTV-SIB) regression and motion during chemo-radiotherapy (CRT) for cervical cancer, and to monitor treatment progress dosimetrically and volumetrically to ensure treatment goals are met. METHODS AND MATERIALS: Ten patients treated with standard doses of CRT and brachytherapy were retrospectively re-planned using a helical Tomotherapy - SIB technique for the hypothetical scenario of this feasibility study. Target and organs at risk (OAR) were contoured on deformable fused planning-computed tomography and megavoltage computed tomography images. The CTV-SIB volume regression was determined. The center of mass (CM) was used to evaluate the degree of motion. The Dice's similarity coefficient (DSC) was used to assess the spatial overlap of CTV-SIBs between scans. A cumulative dose-volume histogram modeled estimated delivered doses. RESULTS: The CTV-SIB relative reduction was between 31 and 70%. The mean maximum CM change was 12.5, 9, and 3 mm in the superior-inferior, antero-posterior, and right-left dimensions, respectively. The CTV-SIB-DSC approached 1 in the first week of treatment, indicating almost perfect overlap. CTV-SIB-DSC regressed linearly during therapy, and by the end of treatment was 0.5, indicating 50% discordance. Two patients received less than 95% of the prescribed dose. Much higher doses to the OAR were observed. A multiple regression analysis showed a significant interaction between CTV-SIB reduction and OAR dose increase. CONCLUSIONS: The CTV-SIB had important regression and motion during CRT, receiving lower therapeutic doses than expected. The OAR had unpredictable shifts and received higher doses. The use of SIB without frequent adaptation of the treatment plan exposes cervical cancer patients to an unpredictable risk of under-dosing the target and/or overdosing adjacent critical structures. In that scenario, brachytherapy continues to be the gold standard approach.

Le diabète de type 2 est-il uniquement une affaire d'hyperglycémie? Entre science, humanisme et economie [Type 2 diabetes, is it just a case of hyperglycemia? Confusion between the interests of science, humanity and the economy]

The recommendations for the treatment of type 2 diabetic patients are often centered on the glycemia. These clinical trials based on this approach show only a beneficial effects on the prevention of microangiopathy. The coronary artery disease which is the main cause of mortality among these patients, is not reduced. These data should be interpreted with a systemic prospect. The diabetes vascular complications have multifactorial causes and these clinical trials are motivated for the promotion of hypoglycemic agents. Fortunately, the STENO study offers another glance on the treatment of the diabetes, associating multirisk approach and patients' accompaniment. It obliges to have a critical glance on the research often moved by economic issues and gives to the center a humanistic approach based on the therapeutic relation.

Primordial neurosecretory apparatus identified in the choanoflagellate Monosiga brevicollis.

SNARE protein-driven secretion of neurotransmitters from synaptic vesicles is at the center of neuronal communication. In the absence of the cytosolic protein Munc18-1, synaptic secretion comes to a halt. Although it is believed that Munc18-1 orchestrates SNARE complexes, its mode of action is still a matter of debate. In particular, it has been challenging to clarify the role of a tight Munc18/syntaxin 1 complex, because this interaction interferes strongly with syntaxin's ability to form a SNARE complex. In this complex, two regions of syntaxin, the N-peptide and the remainder in closed conformation, bind to Munc18 simultaneously. Until now, this binary complex has been reported for neuronal tissues only, leading to the hypothesis that it might be a specialization of the neuronal secretion apparatus. Here we aimed, by comparing the core secretion machinery of the unicellular choanoflagellate Monosiga brevicollis with that of animals, to reconstruct the ancestral function of the Munc18/syntaxin1 complex. We found that the Munc18/syntaxin 1 complex from M. brevicollis is structurally and functionally highly similar to the vertebrate complex, suggesting that it constitutes a fundamental step in the reaction pathway toward SNARE assembly. We thus propose that the primordial secretion machinery of the common ancestor of choanoflagellates and animals has been co-opted for synaptic roles during the rise of animals.

The effect of lattice defects on Hele-Shaw flow over an etched lattice

We examine the patterns formed by injecting nitrogen gas into the center of a horizontal, radial Hele-Shaw cell filled with paraffin oil. We use smooth plates and etched plates with lattices having different amounts of defects (010 %). In all cases, a quantitative measure of the pattern ramification shows a regular trend with injection rate and cell gap, such that the dimensionless perimeter scales with the dimensionless time. By adding defects to the lattice, we observe increased branching in the pattern morphologies. However, even in this case, the scaling behavior persists. Only the prefactor of the scaling function shows a dependence on the defect density. For different lattice defect densities, we examine the nature of the different morphology phases.