Spin-dependent structure functions g^1\hat g_1 and g^2\hat g_2 for inclusive spin-half baryon production in electron-positron annihilation

Two spin-dependent structure functions $\hat g_1$ and $\hat g_2$ for the inclusive spin-half baryon production in electron-positron annihilation are studied in the context of QCD factorization as well as in the naive quark parton model. As a result, it is found that the sum of $\hat g_1$ and $\hat g_2$ is related to $\hat h_1$ and $\hat g_T$, two quark fragmentation functions defined by Jaffe and Ji. In connection with the measurement of quark fragmentation functions, the possible phenomenological consequences are discussed.Comment: RevTex, four Ps figures, to appear in Phys. Rev.

Master crossover functions for the one-component fluid "subclass"

Introducing three well-defined dimensionless numbers, we establish the link between the scale dilatation method able to estimate master (i.e. unique) singular behaviors of the one-component fluid "subclass" and the universal crossover functions recently estimated [Garrabos and Bervillier, Phys. Rev. E 74, 021113 (2006)] from the bounded results of the massive renormalization scheme applied to the..

Ontology in Coq for a Guided Message Composition

International audienceNatural language generation is based on messages that represent meanings , and goals that are the usual starting points for communicate. How to help people to provide this conceptual input or, in other words, how to communicate thoughts to the computer? In order to express something, one needs to have something to express as an idea, a thought or a concept. The question is how to represent this. In 2009, Michael Zock, Paul Sabatier and Line Jakubiec-Jamet suggested the building of a resource composed of a linguistically motivated ontology, a dictionary and a graph generator. The ontology guides the user to choose among a set of concepts (or words) to build the message from; the dictionary provides knowledge of how to link the chosen elements to yield a message (compositional rules); the graph generator displays the output in visual form (message graph representing the user's input). While the goal of the ontology is to generate (or analyse) sentences and to guide message composition (what to say), the graph's function is to show at an intermediate level the result of the encoding process. The Illico system already proposes a way to help a user for generating (or analyzing) sentences and guiding their composition. Another system, the Drill Tutor, is an exercise generator whose goal is to help people to become fluent in a foreign language. It helps people (users have to make choices from the interface in order to build their messages) to produce a sentence expressing a message from an idea (or a concept) to its linguistic realization (or a correct sentence given in a foreign language). These two systems led us to consider the representation of the conceptual information into a symbolic language; this representation is encoded in a logic system in order to automatically check conceptual well-formedness of messages. This logic system is the Coq system used here only for its high level language. Coq is based on a typed λ-calculus. It is used for analysing conceptual input interpreted as types and also for specifying general definitions representing messages. These definitions are typed and they will be instanciated for type-checking the conceptual well-formedness of messages. 2 Line Jakubiec-Jame

Sources of variation in developmental language disorders: evidence from eye-tracking studies of sentence production

Skilled sentence production involves distinct stages of message conceptualization (deciding what to talk about) and message formulation (deciding how to talk about it). Eye-movement paradigms provide a mechanism for observing how speakers accomplish these aspects of production in real time. These methods have recently been applied to children with autism spectrum disorder (ASD) and specific language impairment (LI) in an effort to reveal qualitative differences between groups in sentence production processes. Findings support a multiple-deficit account in which language production is influenced not only by lexical and syntactic constraints, but also by variation in attention control, inhibition and social competence. Thus, children with ASD are especially vulnerable to atypical patterns of visual inspection and verbal utterance. The potential to influence attentional focus and prime appropriate language structures are considered as a mechanism for facilitating language adaptation and learning

Effects of patch size and number within a simple model of patchy colloids

We report on a computer simulation and integral equation study of a simple model of patchy spheres, each of whose surfaces is decorated with two opposite attractive caps, as a function of the fraction $\chi$ of covered attractive surface. The simple model explored --- the two-patch Kern-Frenkel model --- interpolates between a square-well and a hard-sphere potential on changing the coverage $\chi$. We show that integral equation theory provides quantitative predictions in the entire explored region of temperatures and densities from the square-well limit $\chi = 1.0$ down to $\chi \approx 0.6$. For smaller $\chi$, good numerical convergence of the equations is achieved only at temperatures larger than the gas-liquid critical point, where however integral equation theory provides a complete description of the angular dependence. These results are contrasted with those for the one-patch case. We investigate the remaining region of coverage via numerical simulation and show how the gas-liquid critical point moves to smaller densities and temperatures on decreasing $\chi$. Below $\chi \approx 0.3$, crystallization prevents the possibility of observing the evolution of the line of critical points, providing the angular analog of the disappearance of the liquid as an equilibrium phase on decreasing the range for spherical potentials. Finally, we show that the stable ordered phase evolves on decreasing $\chi$ from a three-dimensional crystal of interconnected planes to a two-dimensional independent-planes structure to a one-dimensional fluid of chains when the one-bond-per-patch limit is eventually reached.Comment: 26 pages, 11 figures, J. Chem. Phys. in pres

Models linking production and comprehension

To what extent are linguistic representations shared between production and comprehension? What is the nature of the links between production and comprehension processes? In this chapter, we provide an introduction to those models that incorporate explicit assumptions about the degree of sharing and review some supporting evidence. We show that full sharing of representations is uncontroversial only for semantics and syntax, while there is mixed evidence over the degree of overlapping at the level of phonological and phonetic representations. We then propose a taxonomy of production‐comprehension links, ranging from long‐term to fast‐acting. To conclude, we advocate more explicit theorizing about the relationship between language production and language comprehension

Gravity‐induced density and concentration profiles in binary mixtures near gas–liquid critical lines

We have calculated gravity‐induced density and concentration gradients using scaled equations of state fashioned after that of Leung and Griffiths for binary mixtures near gas–liquid critical lines. The mixtures considered here are those of helium‐3 and helium‐4 and of carbon dioxide and ethane. Our calculations show that the density profiles for both mixtures in any proportion of the components are similar to those of pure fluids. The concentration gradients in the helium mixture have the same appearance as the density gradients. In the carbon dioxide–ethane system, however, the form of the concentration profile varies greatly, depending on the overall composition. Moreover, the temperature at which a mixture separates into two phases is slightly different from that expected for the mixture in the absence of gravity. We have also examined the case where a mixture is subjected to a large gravitational field such as can be generated in a centrifuge and found that, although the density gradient in all the mixtures is like that in pure fluids, the concentration gradients in the mixtures of carbon dioxide and ethane have complex features related to the presence of critical azeotropy

Notch1 Sigaling in Pyramidal Neurons regulates Synaptic Connectivity and Experience-Dependant Modifications of acuity in the Visual Cortex

How the visual cortex responds to specific stimuli is strongly influenced by visual experience during development. Monocular deprivation, for example, changes the likelihood of neurons in the visual cortex to respond to input from the deprived eye and reduces its visual acuity. Because these functional changes are accompanied by extensive reorganization of neurite morphology and dendritic spine turnover, genes regulating neuronal morphology are likely to be involved in visual plasticity. In recent years, Notch1 has been shown to mediate contact inhibition of neurite outgrowth in postmitotic neurons and implicated in the pathogenesis of various degenerative diseases of the CNS. Here, we provide the first evidence for the involvement of neuronal Notch1 signaling in synaptic morphology and plasticity in the visual cortex. By making use of the Cre/Lox system, we expressed an active form of Notch1 in cortical pyramidal neurons several weeks after birth. We show that neuronal Notch1 signals reduce dendritic spine and filopodia densities in a cell-autonomous manner and limit long-term potentiation in the visual cortex. After monocular deprivation, these effects of Notch1 activity predominantly affect responses to visual stimuli with higher spatial frequencies. This results in an enhanced effect of monocular deprivation on visual acuity. Copyright © 2008 Society for Neuroscience

Middle Convolution and Harnad Duality

We interpret the additive middle convolution operation in terms of the Harnad duality, and as an application, generalize the operation to have a multi-parameter and act on irregular singular systems.Comment: 50 pages; v2: Submitted version once revised according to referees' comment