The intriguing role of spanish language vocabulary knowledge in predicting English reading comprehension.

This study explored a holistic model of English reading comprehension among a sample of 135 Spanish-English bilingual Latina and Latino 4th-grade students This model took into account Spanish language reading skills and language of initial literacy instruction. Controlling for language of instruction, English decoding skill, and English oral language proficiency, the authors explored the effects of Spanish language alphabetic knowledge, fluency, vocabulary knowledge, and listening comprehension on English reading comprehension. Results revealed a significant main effect for Spanish vocabulary knowledge and an interaction between Spanish vocabulary and English fluency, such that faster English readers benefited more from Spanish vocabulary knowledge than their less fluent counterparts. This study demonstrates the existence of literary skills transfer from the 1st to the 2nd language, as well as limits on such transfer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Simon effect with and without awareness of the accessory stimulus.

The authors investigated whether a Simon effect could be observed in an accessory-stimulus Simon task when participants were unaware of the task-irrelevant accessory cue. In Experiment 1A a central visual target was accompanied by a suprathreshold visual lateral cue. A regular Simon effect (i.e., faster cue-response corresponding reaction times [RTs]) was found. Experiment 1B demonstrated that this effect cannot be attributed to perceptual grouping of the target and cue. Experiments 2A, 2B, and 2C showed a reverse Simon effect (i.e., faster noncorresponding RTs) when participants were not aware of the cue. In this condition, the Simon effect would occur relative to the reorientation of attention from the cue, which would initially capture attention, toward the target. This conclusion is supported by the results of Experiments 3A and 3B, in which the reorientation of attention was induced by having the target flash after its onset. With suprathreshold cues either a reverse or regular Simon effect was observed by using a 100-ms or ≥200-ms onset flashing interval, respectively, whereas with subthreshold cues a reverse Simon effect was found irrespective of the interval length. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A super-peer model for resource discovery services in large-scale Grids

As deployed Grids increase from tens to thousands of nodes, peer-to-peer (P2P) techniques and protocols can be used to implement scalable services and applications. The super-peer model is a novel approach that helps the convergence of P2P models and Grid environments and can be used to deploy a P2P information service in Grids. A super-peer serves a single physical organization in a Grid, and manages metadata associated to the resources provided by the nodes of that organization. Super-peers connect to each other to form a peer network at a higher level. This paper examines how the super-peer model can handle membership management and resource discovery services in a multi-organizational Grid. A simulation analysis evaluates the performance of a resource discovery protocol; simulation results can be used to tune protocol parameters in order to increase search efficiency.     

Quantitative Assessment of a Peer-to-peer Cooperative Infrastructure Using Stochastic Well-Formed Nets

Traditional support tools for software engineers, normally based on a client-server architecture, are unsuitable to deal with the new issues emerging from the current (and future) cooperative work scenarios (where connectivity is intrinsically transient, the number of interacting partners dynamically changes, etc.). This paper presents a quantitative assessment of a fully decentralized, peer-to-peer, cooperative infrastructure. Stochastic Well-Formed Nets (SWNs) modelling the new peer-to-peer architecture, and a traditional (client-server) one, are developed and analysed: we used SWNs for their ability to directly exploit the symmetries intrinsically present in the modelled systems, thus greatly reducing the complexity of the analysis. The main goal is to compare the impact of the two alternative protocols on the collaborative work. Together with the performance figures of interest, methodological issues concerning the choice of the most appropriate model abstraction level, the adoption of a compositional modelling approach, and the management of the model complexity are also discussed.     

CAD tools for aesthetic engineering

The role of computers and of computer-aided design tools for the creation of geometrical shapes that will be judged primarily by aesthetic considerations is reviewed. Examples are the procedural generation of abstract geometrical sculpture or the shape optimization of constrained curves and surfaces with some global ‘cost’ functional. Different possibilities for such ‘beauty functionals’ are discussed. Moreover, rapid prototyping tools based on layered manufacturing now add a new dimension to the visualization of emerging designs. Finally, true interactivity of the CAD tools allows a more effective exploration of larger parts of the design space and can thereby result in an actual amplification of the creative process.     

On the design of efficient ATM routing schemes

In this paper we deal with the problem of designing virtual path layouts in ATM networks when the hop-count is given and the load has to be minimized. We first prove a lower bound for networks with arbitrary topology and arbitrary set of connection requests. This result is then applied to derive lower bounds for the following settings: (i) one-to-all (one node has to be connected to all other nodes of the network) in arbitrary networks; (ii) all-to-all (each node has to be connected to all other nodes in the network) in several classes of networks, including planar and k-separable networks and networks of bounded genus. We finally study the all-to-all setting on two-dimensional meshes and we design a virtual path layout for this problem. When the hop-count and the network degree are bounded by constants, our results show that the upper bounds proposed in this paper for the one-to-all problem in arbitrary networks and for the all-to-all problem in two-dimensional mesh networks are asymptotically optimal. Moreover, the general lower bound shows that the algorithm proposed in Gerstel (Ph.D. Thesis, Technion-Haifa, Israel, 1995) for the all-to-all problem in k-separable networks is also asymptotically optimal. The upper bound for mesh networks also shows that the lower bound presented in this paper for the all-to-all problem in planar networks is asymptotically tight.     

Normal Fluid Velocity Profile and Transition from T-1 to T-2 State of Superfluid Turbulence

It has been known for many years that in a circular counterflow pipe there exist two different states of turbulence of helium II: the T-1 state, which appears at low values of heat flux, and the T-2 state, which appears suddenly at higher heat flux and is characterized by a much higher density of quantized vortex lines. Until now the nature of the two turbulent states has been a mystery. To understand this problem we have addressed the issue of the velocity profile of the normal fluid and its stability. The computed critical heat flux of the transition from the T-1 state to the T-2 state is found to be in good agreement with the observations. The result indicates that in the T-1 state the superfluid is turbulent but the normal fluid is still laminar. The T-1 to T-2 transition corresponds to the onset of normal fluid turbulence.     

Fasting and post-methionine load homocyst(e)ine values are correlated with microalbuminuria and could contribute to worsening vascular damage in non-insulin-dependent diabetes mellitus patients

The study aim was to assess the relationship between homocyst(e)inemia and microalbuminuria in non-insulin-dependent diabetes mellitus (NIDDM) patients. The study was performed on 33 NIDDM patients (16 males and 17 females), and 16 healthy control subjects (seven males and nine females). Plasma fasting and post-methionine load homocyst(e)ine (tHcy), together with other parameters that could modify tHcy levels, were assessed. There were no significant differences between NIDDM patients and controls for fasting tHcy (8.12 +/- 3.17 v 7.19 +/- 2.40 micromol/L) and post-methionine load tHcy (26.51 +/- 11.50 v 25.06 +/- 10.76 micromol/L). Moreover, there was a significant correlation between urinary albumin excretion (UAE) and fasting tHcy (r = .340, P = .05) and post-methionine load tHcy (r = .502, P = .004) in NIDDM patients. Fasting tHcy was correlated both with post-methionine load tHcy (r = .429, P = .01) and with vitamin B12 (r = -.349, P = .04) in NIDDM patients. Microalbuminuric NIDDM patients had higher fasting tHcy (9.05 +/- 3.83 micromol/L) than normoalbuminurics (7.12 +/- 1.95 micromol/L). In addition, NIDDM patients with complications presented higher fasting tHcy values than the group without complications (9.61 +/- 3.34 v 6.53 +/- 2.09 micromol/L, Kolmogorov-Smirnov two-sample test for nonparametric data [KS] = 1.794, P = .003), without any other significant differences in the parameters considered. tHcy could be an important risk factor worsening the prognosis in NIDDM patients, especially microalbuminuric patients. Microalbuminuric NIDDM patients could be particularly prone to hyperhomocyst(e)inemia, probably due to endothelial or renal dysfunction with a reduction in the scavenging of tHcy.     

Superfluid Helium Between Rotating Cylinders

The isotopic ordering of H2–D2 mixtures adsorbed at low temperature on graphite in the monolayer range is measured by small angle neutron scattering (SANS). We show that below 8 K, solid mixtures exhibit isotopic clustering at large density (monolayer completion) and a tendency towards the formation of ordered compounds for smaller density (near the commensurate structure).