Developing a Procedure to Model the Establishment of Instructional Control

In a recent paper, we suggested that an agreed account of the referential properties of rules and instructions has yet to be developed (O’Hora & Barnes-Holmes, 2001). In order to address this fundamental issue, procedures are required that establish referential or 'specifying' properties in previously neutral stimuli. The present report summarizes the rationale for this research and outlines procedures that we are currently developing

The differential regulation of Lck kinase phosphorylation sites by CD45 is critical for T cell receptor signaling responses

SummaryThe molecular mechanisms whereby the CD45 tyrosine phosphatase (PTPase) regulates T cell receptor (TCR) signaling responses remain to be elucidated. To investigate this question, we have reconstituted CD45 (encoded by Ptprc)-deficient mice, which display severe defects in thymic development, with five different expression levels of transgenic CD45RO, or with mutant PTPase null or PTPase-low CD45R0. Whereas CD45 PTPase activity was absolutely required for the reconstitution of thymic development, only 3% of wild-type CD45 activity restored T cell numbers and normal cytotoxic T cell responses. Lowering the CD45 expression increased CD4 lineage commitment. Peripheral T cells with very low activity of CD45 phosphatase displayed reduced TCR signaling, whereas intermediate activity caused hyperactivation of CD4+ and CD8+ T cells. These results are explained by a rheostat mechanism whereby CD45 differentially regulates the negatively acting pTyr-505 and positively acting pTyr-394 p56lck tyrosine kinase phosphorylation sites. We propose that high wild-type CD45 expression is necessary to dephosphorylate p56lck pTyr-394, suppressing CD4 T+ cell lineage commitment and hyperactivity

Relational frame theory: A new paradigm for the analysis of social behavior

Recent developments in the analysis of derived relational responding, under the rubric of relational frame theory, have brought several complex language and cognitive phenomena within the empirical reach of the experimental analysis of behavior. The current paper provides an outline of relational frame theory as a new approach to the analysis of language, cognition, and complex behavior more generally. Relational frame theory, it is argued, also provides a suitable paradigm for the analysis of a wide variety of social behavior that is mediated by language. Recent empirical evidence and theoretical interpretations are provided in support of the relational frame approach to social behavior

Modified Medical Research Council scale vs Baseline Dyspnea Index to evaluate dyspnea in chronic obstructive pulmonary disease

International audienceBackground: Assessment of dyspnea in COPD patients relies in clinical practice on the modified Medical Research Council (mMRC) scale, whereas the Baseline Dyspnea Index (BDI) is mainly used in clinical trials. Little is known on the correspondence between the two methods. Methods: Cross-sectional analysis was carried out on data from the French COPD cohort Initiatives BPCO. Dyspnea was assessed by the mMRC scale and the BDI. Spirometry, plethysmography, Hospital Anxiety-Depression Scale, St George's Respiratory Questionnaire, exacerbation rates, and physician-diagnosed comorbidities were obtained. Correlations between mMRC and BDI scores were assessed using Spearman's correlation coefficient. An ordinal response model was used to examine the contribution of clinical data and lung function parameters to mMRC and BDI scores. Results: Data are given as median (interquartile ranges, [IQR]). Two-hundred thirty-nine COPD subjects were analyzed (men 78%, age 65.0 years [57.0; 73.0], forced expiratory volume in 1 second [FEV1] 48% predicted [34; 67]). The mMRC grade and BDI score were, respectively, 1 [1-3] and 6 [4-8]. Both BDI and mMRC scores were significantly correlated at the group level (rho = -0.67; P < 0.0001), but analysis of individual data revealed a large scatter of BDI scores for any given mMRC grade. In multivariate analysis, both mMRC grade and BDI score were independently associated with lower FEV1% pred, higher exacerbation rate, obesity, depression, heart failure, and hyperinflation, as assessed by the inspiratory capacity/total lung capacity ratio. The mMRC dyspnea grade was also associated with the thromboembolic history and low body mass index. Conclusion: Dyspnea is a complex symptom with multiple determinants in COPD patients. Although related to similar factors (including hyperinflation, depression, and heart failure), BDI and mMRC scores likely explore differently the dyspnea intensity in COPD patients and are clearly not interchangeable

Education, intellectual development, and relational frame theory

There is now considerable evidence to support the Relational Frame Theory (RFT) position that arbitrarily applicable relational responding or relational framing is the core behavior that characterizes human language and cognition across contexts. The capacity to frame relationally correlates with linguistic and cognitive performance more generally and specifically with measures of both intellectual ability and educational attainment. It makes sense therefore, that, by training relational framing, intellectual performance and educational attainment can be enhanced. The current chapter reviews current research in support of this exciting proposition

Comparing the effects of an acute bout of physical exercise with an acute bout of interactive mental and physical exercise on electrophysiology and executive functioning in younger and older adults

Background Physical exercise has been shown to improve cognitive and neural functioning in older adults. Aims and methods The current study compared the effects of an acute bout of physical exercise with a bout of interactive mental and physical exercise (i.e., “exergaming”) on executive (Stroop) task performance and event-related potential (ERP) amplitudes in younger and older adults. Results Results revealed enhanced executive task performance in younger and older adults after exercise, with no differences in performance between exercise conditions. Stroop (RT) performance in older adults improved more than in younger adults from pre- to post-exercise. A significant increase in EEG amplitude from pre- to post-exercise was found at the Cz site from 320 to 700 ms post-stimulus for both younger and older adults, with older adults demonstrating a larger Stroop interference effect. While younger adults exhibited overall greater EEG amplitudes than older adults, they showed no differences between congruent and incongruent trials (i.e., minimal interference). Compared to peers with higher BMI (body mass index), older adults with lower BMI showed a greater reduction in Stroop interference effects from pre- to post-exercise. Discussion and conclusions The beneficial effects of an acute bout of physical exercise on cognitive and neural functioning in younger and older adults were confirmed, with no difference between standard exercise and exergaming. Findings suggest that BMI, sometimes used as a proxy for fitness level, may modulate benefits that older adults derive from an acute bout of exercise. Findings have implications for future research that seeks to investigate unique effects of exergaming when compared to standard physical exercise

Heat transport by turbulent Rayleigh-B\'enard convection for $\Pra\ \simeq 0.8and and 3\times 10^{12} \alt \Ra\ \alt 10^{15}:Aspectratio: Aspect ratio \Gamma = 0.50$

We report experimental results for heat-transport measurements, in the form of the Nusselt number \Nu, by turbulent Rayleigh-B\'enard convection in a cylindrical sample of aspect ratio $\Gamma \equiv D/L = 0.50$ ($D = 1.12$ m is the diameter and $L = 2.24$ m the height). The measurements were made using sulfur hexafluoride at pressures up to 19 bars as the fluid. They are for the Rayleigh-number range 3\times 10^{12} \alt \Ra \alt 10^{15} and for Prandtl numbers \Pra\ between 0.79 and 0.86. For \Ra < \Ra^*_1 \simeq 1.4\times 10^{13} we find \Nu = N_0 \Ra^{\gamma_{eff}} with $\gamma_{eff} = 0.312 \pm 0.002$, consistent with classical turbulent Rayleigh-B\'enard convection in a system with laminar boundary layers below the top and above the bottom plate. For \Ra^*_1 < \Ra < \Ra^*_2 (with \Ra^*_2 \simeq 5\times 10^{14}) $\gamma_{eff}$ gradually increases up to $0.37\pm 0.01$. We argue that above \Ra^*_2 the system is in the ultimate state of convection where the boundary layers, both thermal and kinetic, are also turbulent. Several previous measurements for $\Gamma = 0.50$ are re-examined and compared with the present results.Comment: 44 pages, 18 figures, submitted to NJ