Event related potentials reveal that increasing perceptual load leads to increased responses for target stimuli and decreased responses for irrelevant stimuli

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Is the Optimal Implementation Inefficient? Elementarily Not

Sharing graphs are a local and asynchronous implementation of lambda-calculus beta-reduction (or linear logic proof-net cut-elimination) that avoids useless duplications. Empirical benchmarks suggest that they are one of the most efficient machineries, when one wants to fully exploit the higher-order features of lambda-calculus. However, we still lack confirming grounds with theoretical solidity to dispel uncertainties about the adoption of sharing graphs. Aiming at analysing in detail the worst-case overhead cost of sharing operators, we restrict to the case of elementary and light linear logic, two subsystems with bounded computational complexity of multiplicative exponential linear logic. In these two cases, the bookkeeping component is unnecessary, and sharing graphs are simplified to the so-called "abstract algorithm". By a modular cost comparison over a syntactical simulation, we prove that the overhead of shared reductions is quadratically bounded to cost of the naive implementation, i.e. proof-net reduction. This result generalises and strengthens a previous complexity result, and implies that the price of sharing is negligible, if compared to the obtainable benefits on reductions requiring a large amount of duplication

Nuclear Magnetic Resonance and Molecular Dynamics Simulation of the Interaction between Recognition Protein H7 of the Novel Influenza Virus H7N9 and Glycan Cell Surface Receptors

Avian influenza A viruses, which can also propagate between humans, present serious pandemic threats, particularly in Asia. The specificity (selectivity) of interactions between the recognition protein hemagglutinin (HA) of the virus capsid and the glycoconjugates of host cells also contributes to the efficient spread of the virus by aerosol between humans. Some avian origin viruses, such as H1N1 (South Carolina 1918), have improved their selectivity for human receptors by mutation in the HA receptor binding site, to generate pandemic viruses. Molecular details and dynamics of glycan–HA interactions are of interest, both in predicting the pandemic potential of a new emerging strain and in searching for new antiviral drugs. Two complementary techniques, ¹H saturation transfer difference (¹H STD) nuclear magnetic resonance and molecular dynamics (MD) simulation, were applied to analyze the interaction of the new H7 (A/Anhui/1/13 H7N9) with LSTa [Neu5Ac α(2→3) Gal β(1→3) GlcNAc β(1→3) Gal β(1→4) Glc] and LSTc [Neu5Ac α(2→6) Gal β(1→4) GlcNAc β(1→3) Gal β(1→4) Glc] pentasaccharides, models of avian and human receptor glycans. Their interactions with H7 were analyzed for the first time using ¹H STD and MD, revealing structural and dynamic behavior that could not be obtained from crystal structures, and contributing to glycan–HA specificity. This highlighted aspects that could affect glycan–HA recognition, including the mutation H7 G228S, which increases H2 and H3 specificity for the human receptor. Finally, interactions between LSTc and H7 were compared with those between LSTc and H1 of H1N1 (South Carolina 1918), contributing to our understanding of the recognition ability of HAs

Human (α2→6) and Avian (α2→3) Sialylated Receptors of Influenza A Virus Show Distinct Conformations and Dynamics in Solution

Differential interactions between influenza A virus protein hemagglutinin (HA) and α2→3 (avian) or α2→6 (human) sialylated glycan receptors play an important role in governing host specificity and adaptation of the virus. Previous analysis of HA–glycan interactions with trisaccharides showed that, in addition to the terminal sialic acid linkage, the conformation and topology of the glycans, while they are bound to HA, are key factors in regulating these interactions. Here, the solution conformation and dynamics of two representative avian and human glycan pentasaccharide receptors [LSTa, Neu5Ac-α(2→3)-Gal-β(1→3)-GlcNAc-β(1→3)-Gal-β(1→4)-Glc; LSTc, (Neu5Ac-α(2→6)-Gal-β(1→4)-GlcNAc-β(1→3)-Gal-β(1→4)-Glc] have been explored using nuclear magnetic resonance and molecular dynamics simulation. Analyses demonstrate that, in solution, human and avian receptors sample distinct conformations, topologies, and dynamics. These unique features of avian and human receptors in solution could represent distinct molecular characteristics for recognition by HA, thereby providing the HA–glycan interaction specificity in influenza.Finlombardia SPAConselho Nacional de Pesquisas (Brazil)National Institutes of Health (U.S.) (R37 GM057073-13)Singapore. National Research Foundation (Singapore-MIT Alliance for Research and Technology

Atomic Details of the Interactions of Glycosaminoglycans with Amyloid-β Fibrils

The amyloid plaques associated with Alzheimer's disease (AD) comprise fibrillar amyloid-β (Aβ) peptides as well as non-protein factors including glycosaminoglycan (GAG) polysaccharides. GAGs affect the kinetics and pathway of Aβ self-assembly and can impede fibril clearance; thus, they may be accessory molecules in AD. Here we report the first high-resolution details of GAG-Aβ fibril interactions from the perspective of the saccharide. Binding analysis indicated that the GAG proxy heparin has a remarkably high affinity for Aβ fibrils with 3-fold cross-sectional symmetry (3Q). Chemical synthesis of a uniformly 13C-labeled octasaccharide heparin analogue enabled magic-angle spinning solid-state NMR of the GAG bound to 3Q fibrils, and measurements of dynamics revealed a tight complex in which all saccharide residues are restrained without undergoing substantial conformational changes. Intramolecular 13C-15N dipolar dephasing is consistent with close (<5 Å) contact between GAG anomeric position(s) and one or more histidine residues in the fibrils. These data provide a detailed model for the interaction between 3Q-seeded Aβ40 fibrils and a major non-protein component of AD plaques, and they reveal that GAG-amyloid interactions display a range of affinities that critically depend on the precise details of the fibril architecture

L’organisation du temps libre : les foyers du soldat en Italie

L’Italie entre en guerre le 24 mai 1915, presque dix mois après les autres puissances. Auparavant, ni l’armée ni l’État n’étudient un éventuel plan d’action pour le temps libre des combattants. Si les autorités civiles et militaires étaient pleinement convaincues que la guerre serait de courte durée, la principale raison de cette carence trouve son origine dans la traditionnelle passivité des pouvoirs publics en matière d’assistance aux classes défavorisées, y compris concernant leur temps li..

PALEOBIOLOGY FROM MUSEUM COLLECTIONS: COMPARING HISTORICAL AND NOVEL DATA ON UPPER MIOCENE MOLLUSCS OF THE LIVORNO HILLS

The upper Miocene mollusc collection from Monti Livornesi, Italy, collected more than a century ago, is confronted with new collections coming from the same localities of Popogna and Quarata. The study concerns the comparison of abundance data of three distinct fossil assemblages from the three vertically-stacked stratigraphic units called Luppiano, Rosignano and Raquese, of upper Tortonian-early Messinian age. Literature and museological data allowed to attribute most museum specimens to one and only one fossil assemblage. Museum collections preserve roughly the same dominant species, with similar ranks as the new quantitative field collections. Significant differences are however evident in the Luppiano assemblage from brackish-water, shallow subtidal bottoms, because new samples yield many species of small size, some of which with high dominance, that are completely lacking in museum collections, suggesting a bias due to size sorting and hinting at the overwhelming contribution of small-sized species to global mollusc diversity. On the other hand the Raquese assemblage, from an open marine shelf setting, can be similarly interpreted from the study of either the museum of new collection, yielding a similar species list and rank. The Rosignano mollusc assemblage, from a bioclastic bottom near a coral patch reef and characterised by fossils with a distinct taphonomic signature, is insufficiently represented in both historical and new collections. The systematics of the three assemblages are revised. The study contributes to the growing literature on museum “dark data” by showing that museum collections may yield abundance data significant for paleobiological analysis

Wheat Grain Composition, Dough Rheology and Bread Quality as Affected by Nitrogen and Sulfur Fertilization and Seeding Density

Flour from old varieties are usually considered very weak flours, and thus difficult to use in breadmaking especially when processed as Italian \u201cTipo 2\u201d flour. Hence, the aim of our study was to understand if agronomic treatments can be used to improve flour processability and the quality of three old wheat varieties. An experimental strip-plot scheme was used: three old wheat varieties (Andriolo, Sieve, Verna), two seeding densities, three levels of nitrogen fertilization (N35, N80, and N135), and two levels of foliar sulfur fertilization. Analyzed parameters related to kernel composition, dough rheology and bread quality. Sulfur and nitrogen treatments significantly affected protein composition and dough alveograph strength, which increased by about 34% with nitrogen fertilization, and by about 14% with the sulfur treatment. However, only nitrogen fertilization affected bread characteristics. Crumb density significantly decreased from N35 to N135, while springiness and cohesiveness increased. On the other hand, sulfur did not improve breads. This highlight the importance of performing breadmaking tests in addition to the rheological determinations. The poor technological performance of old wheat flours can be improved with agronomical treatments designed to obtain higher-quality bread

Planck LFI – Test Report on the TMH/TQL (QM and FM) by Using A Known Signal Tests Data

Version 1.2 provided as reference document for the Planck SGS Implementation Review (2006)This document describes methods, test procedures and results of the validation of TMH/TQL by using a signal generator. The Flight Model (FM) version of the TMH/TQL includes only bug fixes to the Qualification Model version (found during the QM testing) and a change in the interpretation of the tertiary header of the scientific telemetry packets, due to a modification in the header structure performed by Laben (Alcatel Alenia Space - Milan) in June 2006. Note that the data set acquired to perform the described test is always applied before any release of Operational Model, to validate its correct telemetry handling