Age of second language acquisition affects nonverbal conflict processing in children : an fMRI study

Background: In their daily communication, bilinguals switch between two languages, a process that involves the selection of a target language and minimization of interference from a nontarget language. Previous studies have uncovered the neural structure in bilinguals and the activation patterns associated with performing verbal conflict tasks. One question that remains, however is whether this extra verbal switching affects brain function during nonverbal conflict tasks. Methods: In this study, we have used fMRI to investigate the impact of bilingualism in children performing two nonverbal tasks involving stimulus-stimulus and stimulus-response conflicts. Three groups of 8-11-year-old children - bilinguals from birth (2L1), second language learners (L2L), and a control group of monolinguals (1L1) - were scanned while performing a color Simon and a numerical Stroop task. Reaction times and accuracy were logged. Results: Compared to monolingual controls, bilingual children showed higher behavioral congruency effect of these tasks, which is matched by the recruitment of brain regions that are generally used in general cognitive control, language processing or to solve language conflict situations in bilinguals (caudate nucleus, posterior cingulate gyrus, STG, precuneus). Further, the activation of these areas was found to be higher in 2L1 compared to L2L. Conclusion: The coupling of longer reaction times to the recruitment of extra language-related brain areas supports the hypothesis that when dealing with language conflicts the specialization of bilinguals hampers the way they can process with nonverbal conflicts, at least at early stages in life

The Negativity Bias Predicts Response Rate To Behavioral Activation For Depression

Background and Objectives: This treatment study investigated the extent to which asymmetric dimensions of affective responding, specifically the positivity offset and the negativity bias, at pretreatment altered the rate of response to Behavioral Activation treatment for depression. Method: Forty-one depressed participants were enrolled into 16 weekly sessions of BA. An additional 36 lifetime healthy participants were evaluated prospectively for 16 weeks to compare affective responding between healthy and remitted patients at post-treatment. All participants were assessed at Weeks 0, 8 and 16 using repeated measures, involving a structured clinical interview for DSM-IV Axis I disorders, questionnaires, and a computerized task designed to measure affective responses to unpleasant, neutral, and pleasant images. Results: The negativity bias at pre-treatment predicted the rate of response to BA, while the positivity offset did not. Limitations: Only one treatment condition was used in this study and untreated depressed participants were not enrolled, limiting our ability to compare the effect of BA. Conclusions: Baseline negativity bias may serve as a signal for patients to engage in and benefit from the goal-directed BA strategies, thereby accelerating rate of response

Frequency drives lexical access in reading but not in speaking: the frequency-lag hypothesis

To contrast mechanisms of lexical access in production versus comprehension we compared the effects of word frequency (high, low), context (none, low constraint, high constraint), and level of English proficiency (monolingual, Spanish-English bilingual, Dutch-English bilingual) on picture naming, lexical decision, and eye fixation times. Semantic constraint effects were larger in production than in reading. Frequency effects were larger in production than in reading without constraining context but larger in reading than in production with constraining context. Bilingual disadvantages were modulated by frequency in production but not in eye fixation times, were not smaller in low-constraint contexts, and were reduced by high-constraint contexts only in production and only at the lowest level of English proficiency. These results challenge existing accounts of bilingual disadvantages and reveal fundamentally different processes during lexical access across modalities, entailing a primarily semantically driven search in production but a frequency-driven search in comprehension. The apparently more interactive process in production than comprehension could simply reflect a greater number of frequency-sensitive processing stages in production

The academic game: Compliance and resistance in universities

This article draws on the sociology of Bourdieu to explore how academics respond to managerialist imperatives. Bourdieu’s metaphor of the game is applied to a case study of a regional Australian university, which underwent significant changes in 2007, the most notable being the introduction of performance appraisals. In-depth interviews (N=20) reveal evidence of symbolic violence: staff compliance with and complicity in the changes. This is evident in the way that the interviewees, mostly early career academics, chose to play the game by concentrating their efforts on increasing their capital within the new order. To further support this argument, signs of resistance to the new regime were explored. Findings show that vocal resistance was sparse with silence, neglect and exit being the more realistic options. The article concludes that it is academics’ illusio, their unwavering commitment to the game, which neutralizes resistance by pitting colleagues against each other

Modeling Scramjet Supersonic Combustion Via Eddy Dissipation Model

Scramjet technology has gained considerable interest in multi-stage to orbit design concepts due to its reusability and high specific impulse at high-Mach regimes. The aim of the present work is to introduce Reynolds Averaged Navier-Stokes CFD calculations in the design phase of scramjet vehicles and increase the fidelity of engine performance assessment. The turbulence-chemistry interaction is described by the Eddy Dissipation Model (EDM) introduced by Magnussen and Hjertager, which assumes that turbulent motions and not chemistry is the main driver in the rate of combustion. The use of the EDM is explored by application to three hydrogen fueled scramjet test cases. The model requires constants to be prescribed, which have found to be case dependent. Optimal values for the cases simulated are discussed along with appropriateness of the model for general design simulations. The advantage in computational cost is demonstrated by comparison with a no-model finite-rate chemistry approach

Initialization and Ensemble Generation for Decadal Climate Predictions: A Comparison of Different Methods

Five initialization and ensemble generation methods are investigated with respect to their impact on the prediction skill of the German decadal prediction system “Mittelfristige Klimaprognose” (MiKlip). Among the tested methods, three tackle aspects of model‐consistent initialization using the ensemble Kalman filter, the filtered anomaly initialization, and the initialization method by partially coupled spin‐up (MODINI). The remaining two methods alter the ensemble generation: the ensemble dispersion filter corrects each ensemble member with the ensemble mean during model integration. And the bred vectors perturb the climate state using the fastest growing modes. The new methods are compared against the latest MiKlip system in the low‐resolution configuration (Preop‐LR), which uses lagging the climate state by a few days for ensemble generation and nudging toward ocean and atmosphere reanalyses for initialization. Results show that the tested methods provide an added value for the prediction skill as compared to Preop‐LR in that they improve prediction skill over the eastern and central Pacific and different regions in the North Atlantic Ocean. In this respect, the ensemble Kalman filter and filtered anomaly initialization show the most distinct improvements over Preop‐LR for surface temperatures and upper ocean heat content, followed by the bred vectors, the ensemble dispersion filter, and MODINI. However, no single method exists that is superior to the others with respect to all metrics considered. In particular, all methods affect the Atlantic Meridional Overturning Circulation in different ways, both with respect to the basin‐wide long‐term mean and variability and with respect to the temporal evolution at the 26° N latitude

Development of Casbar: a Two-phase Flow Code for the Interior Ballistics Problem

Accurate modelling of gun interior ballistic processes aids in the design and analysis of guns and their propelling charges. Presently, the most accurate modelling of the interior ballistics problem is provided by two-phase, multidimensional computational fluid dynamics (CFD) codes. We present our development of a CFD code, Casbar, which solves a two-phase (gas/particulate) flow problem in axisymmetric geometries. Our model is based on the governing equations for two-phase flow derived from separated flow theory. A finite-volume discretisation of the governing equations is used. The resulting set of equations is solved with a timestep-splitting approach based on the separation of various physical processes. We also present the modelling for the component physics such as propellant combustion and interphase drag. In addition, the solver includes the motion of the projectile and its influence on the flow dynamics. The capabilities of the code are demonstrated with some verification exercises

Twice The Negativity Bias And Half The Positivity Offset: Evaluative Responses To Emotional Information In Depression

Background and objectives: Humans have the dual capacity to assign a slightly pleasant valence to neutral stimuli (the positivity offset) to encourage approach behaviors, as well as to assign a higher negative valence to unpleasant images relative to the positive valence to equally arousing and extreme pleasant images (the negativity bias) to facilitate defensive strategies. We conducted an experimental psychopathology study to examine the extent to which the negativity bias and the positivity offset differ in participants with and without major depression. Method: Forty-one depressed and thirty-six healthy participants were evaluated using a structured clinical interview for DSM-IV Axis I disorders, questionnaires, and a computerized task designed to measure implicit affective responses to unpleasant, neutral, and pleasant stimuli. Results: The negativity bias was significantly higher and the positivity offset was significantly lower in depressed relative to healthy participants. Limitations: Entry criteria enrolling medication-free participants with minimal DSM-IV comorbidity may limit generalizability of the findings. Conclusions: This study advances our understanding of the positive and negative valence systems in depression, highlighting the irregularities in the positive valence system