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We present a generic algorithm for numbering and then efficiently iterating over the data values attached to an extruded mesh. An extruded mesh is formed by replicating an existing mesh, assumed to be unstructured, to form layers of prismatic cells. Applications of extruded meshes include, but are not limited to, the representation of 3D high aspect ratio domains employed by geophysical finite element simulations. These meshes are structured in the extruded direction. The algorithm presented here exploits this structure to avoid the performance penalty traditionally associated with unstructured meshes. We evaluate the implementation of this algorithm in the Firedrake finite element system on a range of low compute intensity operations which constitute worst cases for data layout performance exploration. The experiments show that having structure along the extruded direction enables the cost of the indirect data accesses to be amortized after 10-20 layers as long as the underlying mesh is well-ordered. We characterise the resulting spatial and temporal reuse in a representative set of both continuous-Galerkin and discontinuous-Galerkin discretisations. On meshes with realistic numbers of layers the performance achieved is between 70% and 90% of a theoretical hardware-specific limit., Bibliography fixes, 23 pages

Visual understanding of 3-D environments in real time, at low power, is a huge computational challenge. Often referred to as simultaneous localization and mapping (SLAM), it is central to applications spanning domestic and industrial robotics, autonomous vehicles, and virtual and augmented reality. This paper describes the results of a major research effort to assemble the algorithms, architectures, tools, and systems software needed to enable delivery of SLAM, by supporting applications specialists in selecting and configuring the appropriate algorithm and the appropriate hardware, and compilation pathway, to meet their performance, accuracy, and energy consumption goals. The major contributions we present are: 1) tools and methodology for systematic quantitative evaluation of SLAM algorithms; 2) automated, machine-learning-guided exploration of the algorithmic and implementation design space with respect to multiple objectives; 3) end-to-end simulation tools to enable optimization of heterogeneous, accelerated architectures for the specific algorithmic requirements of the various SLAM algorithmic approaches; and 4) tools for delivering, where appropriate, accelerated, adaptive SLAM solutions in a managed, JIT-compiled, adaptive runtime context.

Objective: The present study aimed at exploring the prevalence of Internet Addiction (IA) amongst a group of high-school students living in Southern Italy. Method: 560 hundred students of both sexes of a “Liceo Classico” who volenteered for the study were included. They completed a smaller version of a specific questionnaire for IA developed by us. Results: 500, out of the total of 560 questionnaires that were returned, were correctly completed and could be analyzed. The main findings were that almost all students used the smartphone to access Internet. About 16% of them used it for a time ranging between 90 and 120 minutes a day, and the remaining less than one hour. The most used applications were Facebook and Whatsup. Fifty percent of the students owned a videogame console, and dedicated less than two hours a day on videogames. The ensuing data were presented to the students and a debate was promoted amongst them. Conclusions: Internet and related technology are now part of the everyday life especially of adolescents. The benefits and limits of them should be underlined. On the same time, an incresead awareness on the possibility of developing an excessive use until a real addiction should be promoted amongst younger generations.

International audience; Linear features are commonly found on small bodies and can have a geomorphic or tectonic origin. Generally, these features are studied by means of morphological analyses. Here we propose a spectroscopic analyses of linear features of different asteroids visited by space missions, in order to search for correspondence between spectral properties and origin of linear features.

to be published in IEEE xplore; International audience

Secondo le tesi più aggiornate di pedagogia durante ogni svolgimento didattico si trasforma non solo la base discente, ma anche il corpo docente. Ma se nel corso di ogni processo di istruzione si registra sempre un spostamento, sia pure minimo, nelle convinzioni di chi insegna e si utilizza la prova di apprendimento per aggiustare il tiro in vista di futuri impegni, in questo caso l’obbligo di aggiornamento della docenza appare ineludibile. Questo è il messaggio più forte di questa esperienza.

Scaturito da un programma internazionale di collaborazione universitaria, il libro indaga sui modi di progettare e recuperare in maniera sostenibile luoghi speciali attraverso osservazioni e scelte fatte lungo un cammino. Renata Valente sviluppa il tema della percorrenza e della lettura attraverso le componenti ambientali, presentando la ricerca su gli spazi tra zone notevoli, mediante la teoria dell’ascolto e dell’osservazione. Partendo da una ricognizione critica dei movimenti di pensiero e delle linee di ricerca internazionale, documenta lo stato dell’arte della riflessione scientifica sul concetto di pedonabilità e sulle categorie di esigenze ad essa collegate, includendo una trattazione sulla tradizione del progetto delle greenways. Salvatore Cozzolino delinea possibili occasioni di riqualificazione dell’ambiente lavorando sul limite dell’impossibile negli interstizi urbani, dimostrando come gli esempi di alcuni progetti iconici esprimano con chiarezza le teorie espresse con la passione del fervente professionista. Lucio Nardi descrive in maniera anticonvenzionale il tragitto che lo ha portato dalla Germania al lavoro comune, lo sfalsamento delle sue destinazioni e le conseguenze indotte. Il “Tentativo sul luogo”, titolo derivato dalla serie di “tentativi” di Peter Handke, considera i punti di vista dai quali studiare il rapporto tra progetto d’architettura e luogo. Nella conversazione con i designer della planimetria di Berlin am Meer, oltre al legame negato e desiderato tra Berlino ed il mare, tratta delle voci dei passi perduti, per concludersi con le voci delle nazionalità diverse che si confrontano sul proprio concetto di mediterraneo. Considerando le diverse provenienze di formazione degli autori, questo libro testimonia l’utilità dello sforzo di trovare codici di scambio disciplinare per arricchire la complessità e la profondità della propria ricerca. Il progetto ambientale si nutre di tale complessità per definizione scientifica e caratterizzazione culturale.

Channel widening taking place during large flood events can be substantial in mountain rivers, with consequent great potential damages to infrastructures and buildings. The purpose of this work is twofold: i) to provide a quantitative assessment of geomorphic effects of an extreme flood event (recurrence interval > 100 years); ii) to test on this study case a new hydromorphological methodological framework (IDRAIM) developed to guide river corridor planning and management. As to the first objective, field surveys were integrated with remote sensing, GIS and statistical analyses for a flood event occurred in 2011 in Northwestern Italy. Channel widening ratios (width after / width before the flood) were calculated and then correlated with different controlling factors, and envelope relationships were then obtained. The tool of the IDRAIM framework used for the second objective was the Event Dynamics Classification (EDC) applied to selected study reaches, whose widening ratios turned out to correspond well with the EDC classes. Based on the results obtained, a practical procedure for predicting the expected widening is finally proposed.

A high-magnitude flash flood, which took place on 25 October 2011 in the Magra River catchment (1717km2), central-northern Italy, is used to illustrate some aspects of the geomorphic response to the flood. An overall methodological framework is described for using interlinked observations and analyses of the geomorphic impacts of an extreme event. The following methods and analyses were carried out: (i) hydrological and hydraulic analysis of the event; (ii) sediment delivery by event landslide mapping; (iii) identification and estimation of wood recruitment, deposition, and budgeting; (iv) interpretation of morphological processes by analysing fluvial deposits; (v) remote sensing and geographic information system (GIS) analysis of channel width changes. In response to the high-magnitude hydrological event, a large number of landslides occurred, consisting of earth flows, soil slips, and translational slides, and a large quantity of wood was recruited, in most part deriving from floodplain erosion caused by bank retreat and channel widening. The most important impact of the flood event within the valley floor was an impressive widening of the overall channel bed and the reactivation of wide portions of the pre-event floodplain. Along the investigated (unconfined or partly confined) streams (total investigated length of 93.5 km), the channel width after the flood was up to about 20 times the channel width before the event. The study has shown that a synergic use of different methods and types of evidence provides fundamental information for characterizing and understanding the geomorphic effects of intense flood events. The prediction of geomorphic response to a flood event is still challenging and many limitations exist; however a robust geomorphological analysis can contribute to the identification of the most critical reaches.

The research objective for Deliverable 2.1 is to develop a process-based, multi-scale, hierarchical framework to support river managers in assessing the hydromorphological character of rivers, exploring the causes of hydromorphological problems, and devising sustainable management solutions. Part 2 of Deliverable 2.1 provides fuller details concerning some specific topics outlined in Part 1.

EGU General Assembly 2011, 3-8 Abril 2011, Viena (Austria)

Background: Glutamine and proline are metabolized the liver and may collaborate on its regeneration. Parenteral nutrition (PN) containing either glutamine or proline was given to partially hepatectomized rats. The total RNA content and growth factor gene expression in hepatic remnants was measured, to determine the effects of these amino acid supplementation on the expression ofgrowth factors during liver regeneration. Methods: Wistar rats nourished (HN) and malnourished (HM) were hepatectomized and divided in two groups: 20 receiving PN enriched with Alanyl-Glutamine (HN-Gln and HM-Gln) and 20 PN enriched with proline+alanine (HN-Pro and HM-Pro). The control groups comprised 7 nourished (CN) and 7 malnourished (CM) rats that didn't undergo surgery. Growth factor and thymidine kinase mRNA levels were measured by RT-PCR. Results: In nourished rats, total hepatic RNA levels were lower in the HN-Gln and HN-Pro groups (0.75 and 0.63 μg/mg tissue, respectively) than in control group (1.67 μg/mg tissue) (P < 0.05). In malnourished rats, total hepatic RNA content was higher in the HM-Pro group than HN-Pro, HM-Gln, and CM (3.18 vs. 0.63, 0.93 and 1.10 μg/mg, respectively; P < 0.05). Hepatocyte growth factor mRNA was more abundant in the HM-Gln group when compared to CM (0.31 vs. 0.23 arbitrary units) and also in HM-Pro in relation to HM-Gln, HN-Pro, and CM(0.46 vs. 0.33 and 0.23, respectively, P < 0.05). Conclusions: Proline or glutamine supplementation in malnourished rats improves total RNA content in the remnant hepatic tissue. Amino acids administration increased HGF gene expression after partial hepatectomy in malnourished rats, with a greater effect of proline than glutamine. Introducción: La glutamina y la prolina de metabolizan en el hígado y pueden contribuir a la regeneración de este. Se administró nutrición parenteral con glutamina o prolina a ratas sometidas a hepatectomía parcial. Se midieron el contenido de ARN total así como la expresión genética del factor de crecimiento en el tejido hepático remanente, con el objetivo de determinar los efectos que provocaban estos aminoácidos en la expresión genética de factores de crecimiento durante el proceso de regeneración del hígado. Métodos: ratas macho Wistar nutridas (HN) y desnutridas (HM) se sometieron a hepatectomía parcial y se dividieron en dos grupos: 20 recibieron nutrición parenteral enriquecida con Alanil-Glutamina (HN-Gln y HM-Gln) y 20 nutrición parenteral enriquecida con prolina+alanina (HNPro y HM-Pro). Los grupos de control estaban formados por 7 ratas nutridas (CN) y 7 desnutridas (CM) que no se sometieron a la cirugía. Los niveles de factor de crecimiento y timidina quinasa mRNA se midieron por RT-PCR. Resultados: En las ratas nutridas, lo niveles de ARN hepático total fueron inferiores en los grupos que recibieron HNGln y HN-Pro (0,75 y 0,63 mg/mg tejido, respectivamente) que en el grupo control (1,67 mg/mg tejido) (P < 0,05). En las ratas desnutridas, el contenido total de ARN hepático fue superior en el grupo que recibió HM-Pro que el que recibió HN-Pro, HM-Gln y CM (3,18 vs 0,63, 0,93 y 1,10 mg/mg, respectivamente; P < 0,05). El mRNA del factor de crecimiento de hepatocitos fue más abundante en el grupo que recibió HM-Gln con respecto a CM (0,31 vs 0,23 unidades arbitrarias), así como en HM-Pro con relación a HM-Gln, HN-Pro y CM (0,46 vs 0,33 y 0,23, respectivamente, P < 0,05). Discusión: La suplementación de prolina o glutamina en ratas macho desnutridas mejora el contenido total de ARN en el tejido hepático remanente. Al administrarse aminoácidos aumentó la expresión genética del HGF tras someter las ratas desnutridas a una hepatectomía parcial, obteniéndose un resultado mejor con prolina que con glutamina.