Trophonella (Gastropoda: Muricidae), a New Genus from Antarctic Waters, with the Description of a New Species

The new genus Trophonella is described from the outer shelf and upper continental slope of Antarcticaand islands within the Antarctic Convergence. Four previously known species that had been attributed to the genusTrophon (Trophon scotianus Powell, 1951; T. echinolamellatus Powell, 1951; T. enderbyensis Powell, 1958; and T.eversoni Houart, 1997) are included in Trophonella, as is one new species (Trophonella rugosolamellata) describedherein. Trophonella resembles Trophon in gross shell morphology: the members of both genera have large, globoseshells, paucispiral protoconchs, prominent axial lamellae, and short siphonal canals. Trophonella differs fromTrophon in having shells with evenly rounded whorls that lack a well-defined shoulder; rachidian teeth withdistinctive, broadly triangular central cusps, but that lack the marginal cusps of Trophon; characteristic sphericalaccessory salivary glands; and a circumpapillar fold on the penis that is absent in Trophon. Relationships of thegenera Trophon and Trophonella, as well as of the subfamily Trophoninae are reexamined by supplementing the datamatrix of Kool (1993b, Table 3) with data for additional taxa. Results support the segregation of Trophonella fromTrophon at the generic level. Based on the relationships of the type species of their respective nominotypical genera,Trophoninae is either the sister taxon of a narrowly circumscribed Ocenebrinae, or both are part of a larger clade. Abetter resolved phylogeny containing a much broader sampling of the more than 50 genus-level taxa that have beenattributed to these two subfamilies will be required in order to delineate more precisely the membership of the cladeand to identify its diagnostic synapomorphies.Fil: Harasewych, M. G.. National Museum of Natural History; Estados UnidosFil: Pastorino, Roberto Santiago Guido. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentin

Test of a simple and flexible molecule model for alpha-, beta- and gamma-S8 crystals

S8 is the most stable compound of elemental sulfur in solid and liquid phases, at ambient pressure and below 400K. Three crystalline phases of S8 have been clearly identified in this range of thermodynamic parameters, although no calculation of its phase diagram has been performed yet. alpha- and gamma-S8 are orientationally ordered crystals while beta-S8 is measured as orientationally disordered. In this paper we analyze the phase diagram of S8 crystals, as given by a simple and flexible molecule model, via a series of molecular dynamics (MD) simulations. The calculations are performed in the constant pressure- constant temperature ensemble, using an algorithm that is able to reproduce structural phase transitions.Comment: RevTex,7 pages, 5 figures,to appear in J. Chem. Phy

Toward an anisotropic atom-atom model for the crystalline phases of the molecular S8 compound

We analize two anisotropic atom-atom models used to describe the crystalline alpha,beta and gamma phases of S8 crystals, the most stable compound of elemental sulfur in solid phases, at ambient pressure and T<=400 K. The calculations are performed via a series of classical molecular dynamics (MD) simulations, with flexible molecular models and using a constant pressure-constant temperature algorithm for the numerical simulations. All intramolecular modes that mix with lattice modes, and are therefore relevant on the onset of structural phase transitions, are taken into account. Comparisons with experimental data and previous results obtained with an isotropic atom-atom molecular model are also performed.Comment: Major changes, new simulations and figures added, revtex4, to appear in J. Chem. Phy

Cyclic motion and inversion of surface flow direction in a dense polymer brush under shear

Using molecular simulations, we study the properties of a polymer brush in contact with an explicit solvent under Couette and Poiseuille flow. The solvent is comprised of chemically identical chains. We present evidence that individual, unentangled chains in the dense brush exhibit cyclic, tumbling motion and non-Gaussian fluctuations of the molecular orientations similar to the behaviour of isolated tethered chains in shear flow. The collective molecular motion gives rise to an inversion of hydrodynamic flow direction in the vicinity of the brush-coated surface. Utilising Couette and Poiseuille flow, we investigate to what extend the effect of a brush-coated surface can be described by a Navier slip condition.Comment: 6 pages, 6 figures, submitted for publicatio

Static and dynamic properties of the interface between a polymer brush and a melt of identical chains

Molecular dynamics simulations of a short-chain polymer melt between two brush-covered surfaces under shear have been performed. The end-grafted polymers which constitute the brush have the same chemical properties as the free chains in the melt and provide a soft deformable substrate. Polymer chains are described by a coarse-grained bead-spring model with Lennard-Jones interactions between the beads and a FENE potential between nearest neighbors along the backbone of the chains. The grafting density of the brush layer offers a way of controlling the behavior of the surface without altering the molecular interactions. We perform equilibrium and non-equilibrium Molecular Dynamics simulations at constant temperature and volume using the Dissipative Particle Dynamics thermostat. The equilibrium density profiles and the behavior under shear are studied as well as the interdigitation of the melt into the brush, the orientation on different length scales (bond vectors, radius of gyration, and end-to-end vector) of free and grafted chains, and velocity profiles. The viscosity and slippage at the interface are calculated as functions of grafting density and shear velocity.Comment: 12 pages, submitted to J Chem Phy

Semantic Segmentation of Remote-Sensing Images Through Fully Convolutional Neural Networks and Hierarchical Probabilistic Graphical Models

Deep learning (DL) is currently the dominant approach to image classification and segmentation, but the performances of DL methods are remarkably influenced by the quantity and quality of the ground truth (GT) used for training. In this article, a DL method is presented to deal with the semantic segmentation of very-high-resolution (VHR) remote-sensing data in the case of scarce GT. The main idea is to combine a specific type of deep convolutional neural networks (CNNs), namely fully convolutional networks (FCNs), with probabilistic graphical models (PGMs). Our method takes advantage of the intrinsic multiscale behavior of FCNs to deal with multiscale data representations and to connect them to a hierarchical Markov model (e.g., making use of a quadtree). As a consequence, the spatial information present in the data is better exploited, allowing a reduced sensitivity to GT incompleteness to be obtained. The marginal posterior mode (MPM) criterion is used for inference in the proposed framework. To assess the capabilities of the proposed method, the experimental validation is conducted with the ISPRS 2D Semantic Labeling Challenge datasets on the cities of Vaihingen and Potsdam, with some modifications to simulate the spatially sparse GTs that are common in real remote-sensing applications. The results are quite significant, as the proposed approach exhibits a higher producer accuracy than the standard FCNs considered and especially mitigates the impact of scarce GTs on minority classes and small spatial details

Hierarchical Probabilistic Graphical Models and Deep Convolutional Neural Networks for Remote Sensing Image Classification

The method presented in this paper for semantic segmentation of multiresolution remote sensing images involves convolutional neural networks (CNNs), in particular fully convolutional networks (FCNs), and hierarchical probabilistic graphical models (PGMs). These approaches are combined to overcome the limitations in classification accuracy of CNNs for small or non-exhaustive ground truth (GT) datasets. Hierarchical PGMs, e.g., hierarchical Markov random fields (MRFs), are structured output learning models that exploit information contained at different image scales. This perfectly matches the intrinsically multiscale behavior of the processes of a CNN (e.g., pooling layers). The framework consists of a hierarchical MRF on a quadtree and a planar Markov model on each layer, modeling the interactions among pixels and accounting for both the multiscale and the spatial-contextual information. The marginal posterior mode criterion is used for inference. The adopted FCN is the U-Net and the experimental validation is conducted on the ISPRS 2D Semantic Labeling Challenge Vaihingen dataset, with some modifications to approach the case of scarce GTs and to assess the classification accuracy of the proposed technique. The proposed framework attains a higher recall compared to the considered FCNs, progressively more relevant as the training set is further from the ideal case of exhaustive GTs

PERSONALITY AND SOCIALITY IN CAPTIVE ANIMALS: IMPLICATIONS FOR MANAGEMENT

Personality and sociality in captive animals: implications for management Dr. Giovanni Quintavalle Pastorino Matr. n. R10497 ABSTRACT Interactions that animals experience can have a significant influence on their health and welfare. These interactions can occur between animals themselves, but also between animals and keepers, and animals and the public. Human and non-human animals come into contact with each other in a variety of settings, and wherever there is contact there is the opportunity for interaction to take place. Interaction with companion animals are well known, but human\u2013animal interaction (HAR) (Hosey, 2008) also occurs in the context of farms (Hemsworth and Gonyou, 1997; Hemsworth, 2003), laboratories (Chang and Hart, 2002), zoos (Kreger and Mench, 1995) and even the wild (e.g. Cassini, 2001). This PhD proposes an articulated monitoring scheme to record animal-human interactions and animal-animal interactions in selected zoos and farms. This was accompanied by a survey of animal personality in several institutions in the UK and Italy for welfare, husbandry, breeding programs and reintroduction purposes. The methodological approach was based on direct monitoring of animal behaviour, videos of keeper-animal interactions and animal personality questionnaires completed by experienced keepers and animal handlers. The goal of this project is to create a network between zoos to explore the aforementioned interactions to produce husbandry protocols and explore personality and behavioural traits in multiple species. We present data regarding African lions, Asiatic lion, Sumatran tigers, Brown bears and sloth bears (ZSL London and Whipsnade zoo) interactions with humans and conspecifics and personality profiles from five different dairy cattle breeds. This data is collected across a broad range of environmental conditions and outlines the monitoring protocols developed to collect this data. The data show the great adaptability of these species to ex situ environments, low or absent negative impact of visitors\u2019 presence and the relevance of individual personality in these interactions

Social Cognition in Neurodevelopmental Disorders and Epilepsy

Introduction: The purpose of our study was to perform a comparative analysis of social cognition in children and adolescents with epilepsy, autism spectrum disorder (ASD), specific learning disorder (SLD) and in typical development (TD) controls. The secondary aim was to relate social cognition to some clinical and demographic characteristics. Methods: Our work is a transversal observational study. The recruits were 179 children and adolescents aged between 6 and 18 years diagnosed with epilepsy, ASD, or SLD and 32 subjects with TD. All the participants underwent neuropsychological assessment of Emotion Recognition (ER) and Theory of Mind (ToM) skills. Results: All three clinical groups performed significantly worse than controls in ER and ToM. The ASD group achieved significantly lower performance than the other groups; however, the scores of SLD and epilepsy groups were comparable. The ER performances are related to non-verbal intelligence only in the group with epilepsy. Conclusion: Children and adolescents with focal epilepsy, SLD, or ASD may present a deficit of varying extent in emotion recognition and ToM, compared with TD peers. These difficulties are more pronounced in individuals with ASD, but impairment worthy of clinical attention also emerges in individuals with SLD and epilepsy

Variación genética de poblaciones naturales de Ciprés de la Cordillera con regímenes de precipitación contrastados, en la eficiencia del uso del agua de plántulas, a través de la discriminación isotópica del carbono

Water-use efficiency (WUE) is a physiological parameter that plays a significant role in the evolutionary dynamics of many forest tree species. It can be estimated indirectly through carbon isotope discrimination (Δ). In general, plants of more arid origins have lower values of Δ. In order to study the degree of genetic control of this parameter and the genetic variation in Δ of Patagonian Cypress seedlings, three Argentinean natural populations chosen to represent two contrasting precipitation regimes were sampled in a common garden trial. The dry situation was represented by two neighboring marginal forest patches from the steppe, while the humid condition was represented by a population with 1,200 mm higher mean annual precipitation. Height (H) and Δ were measured in 246 five-year-old seedlings from 41 open-pollinated families. The factor ‘family’ had a significant effect on both variables; however heritability for Δ was found not to be significant in two out of the three populations. This could be explained by low sample size in one of them and by a real evolutionary effect in the other. An inverse association between H and Δ was verified, which is interpreted as evidence of an adaptation process at the intra-population level. The studied populations were not shown to discriminate carbon isotopes differently; hence evidence of adaptation to current environmental conditions could not be obtained. On the other hand, the arid populations proved to be quite different in terms of genetic variation, which seems to be the consequence of genetic drift and isolation.La eficiencia en el uso del agua es un parámetro fisiológico que desempeña un rol significativo en la dinámica evolutiva de muchas especies forestales. Puede estimarse indirectamente a través de la discriminación isotópica del carbono (Δ). En general, las plantas de orígenes más áridos tienen valores de Δ más bajos. Con el propósito de estudiar el grado de control genético de Δ y la variación genética en este parámetro en plántulas de Ciprés de la Cordillera, tres poblaciones naturales elegidas para representar dos regímenes de precipitación contrastados fueron muestreadas en un ensayo de ambiente común. La condición árida estuvo representada por dos fragmentos de bosque esteparios marginales, vecinos entre sí, mientras que la condición húmeda fue representada por una población con una precipitación media anual 1.200 mm superior a la de las áridas. Se midió altura total (H) y Δ en 246 plántulas de 5 años de edad correspondientes a 41 familias de polinización abierta. El factor ‘familia’ tuvo un efecto significativo en ambas variables; sin embargo, la heredabilidad para Δ no resultó significativa en dos de las tres poblaciones. En una de ellas esto podría explicarse por el restringido tamaño muestreal, mientras que en la otra por un verdadero efecto evolutivo. Asimismo se verificó una asociación inversa entre H y Δ, la cual es interpretada como evidencia de un proceso de adaptación a nivel intra-poblacional. No se observó que las poblaciones estudiadas discriminaran los isótopos del carbono de un modo diferencial, y por lo tanto no se obtuvieron evidencias de adaptación a las condiciones ambientales actuales. Por otro lado, las poblaciones áridas probaron ser muy diferentes entre sí en términos de variación genética, lo que parece ser la consecuencia de deriva y aislamiento genéticos