Although working memory (WM) figures centrally in many theories of second language (L2) proficiency development and processing, some have argued that the importance of WM is overstated (e.g., Juffs,
...Transactions of the Philological Society, 102
, 199–225,
2004
). Despite many studies over the past two decades, the literature lacks a quantitative synthesis of the extant results. In this article, we report a meta-analysis of data from 79 samples involving 3,707 participants providing 748 effect sizes. The results indicate that WM is positively associated with both L2 processing and proficiency outcomes, with an estimated population effect size (
ρ
) of .255. In additional analyses, we assessed whether the WM–criterion relationship was modulated by potential covariates identified in the literature search (i.e., participant characteristics, WM measure features, criterion measure factors, and publication status). The results of the covariate analyses indicated larger effect sizes for the executive control (vs. storage) component of WM, and for verbal (vs. nonverbal) measures of WM. Minimal publication bias was detected, suggesting that WM has a robust, positive relationship with L2 outcomes. We discuss the implications of these results for models of WM and theories of L2 processing and L2 proficiency development.
Abstract
Objectives
To report methods and findings of 2 autopsies with molecular evaluation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive individuals.
Methods
Postmortem ...examination was completed following Centers for Disease Control and Prevention public guidelines. Numerous formalin-fixed paraffin-embedded (FFPE) tissue types from each case were surveyed for SARS-CoV-2 RNA by quantitative reverse transcription polymerase chain reaction (qRT-PCR). SARS-CoV-2 viral genome was sequenced by next-generation sequencing (NGS) from FFPE lung tissue blocks.
Results
Postmortem examinations revealed diffuse alveolar damage, while no viral-associated hepatic, cardiac, or renal damage was observed. Viral RNA was detected in lungs, bronchi, lymph nodes, and spleen in both cases using qRT-PCR method. RNA sequencing using NGS in case 1 revealed mutations most consistent with Western European Clade A2a with ORF1a L3606F mutation.
Conclusions
SARS-CoV-2 testing and viral sequencing can be performed from FFPE tissue. Detection and sequencing of SARS-CoV-2 in combination with morphological findings from postmortem tissue examination can aid in gaining a better understanding of the virus’s pathophysiologic effects on human health.
An experimental program to demonstrate a novel phase-space manipulation in which the horizontal and longitudinal emittances of a particle beam are exchanged has been completed at the Fermilab A0 ...Photoinjector. A new beam line, consisting of a TM(110) deflecting mode cavity flanked by two horizontally dispersive doglegs has been installed. We report on the first direct observation of transverse and longitudinal emittance exchange.
The Target Absorbers for Neutrals (TANs) represent one of the most radioactive regions in the Large Hadron Collider. Seven 40cm long fused silica rods with different dopant specifications, ...manufactured by Heraeus, were irradiated in one of the TANs located around the ATLAS experiment by the Beam RAte of Neutrals (BRAN) detector group. This campaign took place during Run 2 p＋p data taking, which occurred between 2016 and 2018. This paper reports a complete characterization of optical transmission per unit length of irradiated fused silica materials as a function of wavelength (240 nm–1500 nm), dose (up to 18 MGy), and level of OH and H2 dopants introduced in the manufacturing process. The dose delivered to the rods was estimated using Monte Carlo simulations performed by the CERN FLUKA team.
This paper describes the design and simulation of a proof-of-concept octupole lattice at the University of Maryland Electron Ring (UMER). This experiment tests the feasibility of nonlinear integrable ...optics, a novel technique that is expected to mitigate resonant beam loss and enable low-loss high-intensity beam transport in rings. Integrable lattices with large amplitude-dependent tune spreads, created by nonlinear focusing elements, are proposed to damp beam response to resonant driving perturbations while maintaining large dynamic aperture. At UMER, a lattice with a single octupole insert is designed to test the predictions of this theory. The planned experiment employs a low-current high-emittance beam with low space charge tune shift (∼0.005) to probe the dynamics of a lattice with large externally-induced tune spread. Design studies show that a lattice composed of a 25-cm octupole insert and existing UMER optics can induce a tune spread of∼0.13. Stable transport is observed in PIC simulation for many turns at space charge tune spread 0.008. A maximum spread ofΔν=0.11(rms 0.015) is observed for modest octupole strength (peak50T/m3). A simplified model of the system explores beam sensitivity to steering and focusing errors. Results suggest that control of orbit distortion to<0.2mmwithin the insert region is essential. However, we see only weak dependence on deviations of lattice phase advance (≤0.1rad.) from the invariant-conserving condition.
The Target Absorbers for Neutrals (TANs) are located in a high intensity radiation environment inside the tunnel of the Large Hadron Collider (LHC). TANs are positioned about 140 m downstream from ...the beam interaction points. Seven 40-cm long fused silica rods with different dopant specifications were irradiated in the TAN by the Beam RAte of Neutrals (BRAN) detector group duringp+pdata taking from 2016 to 2018 at the LHC. The peak dose delivered to the fused silica rods was 18 MGy. We report measurements of theNa22activation of the fused silica rods carried out at the University of Illinois at Urbana-Champaign and Argonne National Laboratory. At the end of the irradiation campaign, the maximumNa22activity observed wasA=21kBq/cm3corresponding to a density,ρ=2.5×1012/cm3, ofNa22 nuclei. fluka Monte Carlo simulations have been performed by the CERN fluka team to estimateNa22activities for the irradiated BRAN rod samples. The simulations reproduce theNa22activity profile measured along the rods, with a 35% underestimation of the experimental measurement results.
The Target Absorbers for Neutrals (TANs) are located in a high intensity radiation environment inside the tunnel of the Large Hadron Collider (LHC). TANs are positioned about 140 m downstream from ...the beam interaction points. Seven 40-cm long fused silica rods with different dopant specifications were irradiated in the TAN by the Beam RAte of Neutrals (BRAN) detector group during p+p data taking from 2016 to 2018 at the LHC. The peak dose delivered to the fused silica rods was 18 MGy. We report measurements of the ^{22}Na activation of the fused silica rods carried out at the University of Illinois at Urbana-Champaign and Argonne National Laboratory. At the end of the irradiation campaign, the maximum ^{22}Na activity observed was A=21 kBq/cm^{3} corresponding to a density, ρ=2.5×10^{12}/cm^{3}, of ^{22}Na nuclei. fluka Monte Carlo simulations have been performed by the CERN fluka team to estimate ^{22}Na activities for the irradiated BRAN rod samples. The simulations reproduce the ^{22}Na activity profile measured along the rods, with a 35% underestimation of the experimental measurement results.
In the task-switching paradigm, the latency switch-cost score—
the difference in mean reaction time between switch and nonswitch trials
—is the traditional measure of task-switching ability. However, ...this score does not reflect accuracy, where switch costs may also emerge. In two experiments that varied in response deadlines (unlimited vs. limited time), we evaluated the measurement properties of two traditional switch-cost scoring methods (the latency switch-cost score and the accuracy switch-cost score) and three alternatives (a rate residual score, a bin score, and an inverse efficiency score). Scores from the rate residual, bin score, and inverse efficiency methods had comparable reliability for latency switch-cost scores without response deadlines but were more reliable than latency switch-cost scores when higher error rates were induced with a response deadline. All three alternative scoring methods appropriately accounted for differences in accuracy switch costs when higher error rates were induced, whereas pure latency switch-cost scores did not. Critically, only the rate residual and bin score methods were more valid indicators of task-switching ability; they demonstrated stronger relationships with performance on an independent measure of executive functioning (the antisaccade analogue task), and they allowed the detection of larger effect sizes when examining within-task congruency effects. All of the three alternative scoring methods provide researchers with a better measure of task-switching ability than do traditional scoring methods, because they each simultaneously account for latency and accuracy costs. Overall, the three alternative scoring methods were all superior to the traditional latency switch-cost scoring method, but the strongest methods were the rate residual and bin score methods.
The University of Maryland Electron Ring Program Kishek, R.A.; Beaudoin, B.L.; Bernal, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2014, Letnik:
733
Journal Article
Recenzirano
The University of Maryland Electron Ring (UMER) is a unique machine that uses scaled electron beams at nonrelativistic energies (10keV) to inexpensively model GeV beams of heavy ions over long path ...lengths (kilometers of transport distance). The UMER beam parameters correspond to space charge tune depressions, at injection, adjustable in the range of 0.14–0.85. Although a ring, many of the intense beam studies on UMER are applicable to linacs. This paper reviews the UMER program, which contains experimental, computational, and theoretical components. We outline the research areas of interest, recent accomplishments, and future plans, emphasizing the relevance to heavy ion drivers. Specific topics include longitudinal induction focusing and beam manipulations; generation and propagation of space charge waves, including large-amplitude solitons; bunch end interpenetration and observation of a multi-stream instability; beam halo studies; and diagnostic development.
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