Cognitive emotion regulation questionnaire: Psychometric properties of the Tunisian version.

OBJECTIVES: This study investigated the psychometric properties of the Cognitive Emotion Regulation Questionnaire in a Tunisian Arabic-Speaking population. METHOD: The CERQ original version was translated and back-translated and then administrated to 360 participants. Afterwards, using the explanatory and confirmatory factor analysis, we studied the latent factor structure for CERQ. The internal consistency of the subscales was assessed by Cronbach's alfa coefficients, and the test-retest and interscale reliability were assessed with Pearson correlations. The criterion validity was also examined using correlations between the CERQ subscales and both the Beck Depression Inventory (BDI) and State-Trait Anxiety Inventory (STAI) scales at first evaluation and at a one year follow-up. RESULTS: The Tunisian version was quite satisfactory with the nine-factor structure, as in the original CERQ. Moreover, all validity and reliability measures were comparable to the original CERQ. CONCLUSION: The present study is the first work devoted to a Tunisian adaptation of the CERQ. Our findings highlight that the Tunisian version is both reliable and valid for the measurement of cognitive emotion regulation strategies.

Gestural apraxia.

Gestural apraxia was first described in 1905 by Hugo Karl Liepmann. While his description is still used, the actual terms are often confusing. The cognitive approach using models proposes thinking of the condition in terms of production and conceptual knowledge. The underlying cognitive processes are still being debated, as are also the optimal ways to assess them. Several neuroimaging studies have revealed the involvement of a left-lateralized frontoparietal network, with preferential activation of the superior parietal lobe, intraparietal sulcus and inferior parietal cortex. The presence of apraxia after a stroke is prevalent, and the incidence is sufficient to propose rehabilitation.

Infrared Plasmonics with Conductive Ternary Nitrides.

Conductive transition metal nitrides are emerging as promising alternative plasmonic materials that are refractory and CMOS-compatible. In this work, we show that ternary transition metal nitrides of the B1 structure and consisting of a combination of group-IVb transition metal, such as Ti or Zr, and group III (Sc, Y, Al) or group II (Mg, Ca) elements can have tunable plasmonic activity in the infrared range in contrast to Ta-based ternary nitrides, which exhibit plasmonic performance in the visible and UV ranges. We consider the intrinsic quality factors of surface plasmon polariton for the ternary nitrides, and we calculate the dispersion of surface plasmon polariton and the field enhancement at the vicinity of nitride/silica interfaces. Based on these calculations, it is shown that among these nitrides the most promising are TixSc1-xN and TixMg1-xN. In particular, TixSc1-xN can have plasmonic activity in the usual telecom bands at 850, 1300, and 1550 nm. Still, these nitrides exhibit substantial electronic losses mostly due to fine crystalline grains that deteriorate the plasmonic field enhancement. This unequivocally calls for improved growth processes that would enable the fabrication of such ternary nitrides of high crystallinity.

[Eating behavior in pediatric obesity: Of the advantages of combining the neurobiological and neuropsychological approaches]. / Comportement alimentaire de l'enfant et de l'adolescent souffrant d'obésité : intérêt d'un couplage des approches neurobiologique et neuropsychologique.

Obesity is currently considered a major public health concern, as shown by the growing number of people with excess weight, alarmingly in infants, and despite medical care. Many studies have underlined the reasons for medical care failure caused by an inability to sustain a resistant behavior towards palatable food (high sugar and fat content). Hence, previous research has highlighted connections between excessive eating behavior and the activity of neurotransmitters in brain areas involved in affective behavior and the reward circuit. Reduction of the dopaminergic activity in the prefrontal orbital and limbic cortex may raise the question of executive skills, which play a major role in social adaptation and behavior control. These findings remind us of the need to grasp environmental and behavioral factors to better identify cognitive and affective profiles and improve childhood obesity treatment.

Discrepancy between social and nonsocial decision-making under uncertainty following prefrontal lobe damage: the impact of an interactionist approach.

Deficits in decision-making are thought to contribute significantly to socio-behavioral impairments of patients with frontal lobe damage. The purpose of this study was to test the hypothesis of whether the inappropriate social behavior of patients with frontal lesions can be viewed as the product of a general failure of decision-making ability or as the result of socio-cognitive impairment. We studied a group of patients with prefrontal lesions (FL patients, n = 15) and a group of matched healthy controls (n = 30) on the Iowa Gambling task (IGT) of nonsocial decision-making, environmental dependency phenomena (EDP) during social interaction, and the "reading the mind in the eyes" and "character intention task" of theory of mind (TOM) tasks. The FL patients were impaired in both TOM and EDP protocols but, surprisingly, they behaved appropriately in the IGT. In addition, FL patients with EDP did not differ in executive functioning, IGT and TOM measures from those who did not demonstrate these behavioral disorders. The right orbitofrontal cortex was associated with social decision-making deficits. By adopting an interactionist approach, this study raises the possibility of identifying components of social and nonsocial decision-making, which could be helpful in understanding the behavioral disorders of FL patients.

First-principles phase diagram calculations for the rocksalt-structure quasibinary systems TiN-ZrN, TiN-HfN and ZrN-HfN.

We have studied the phase equilibria of three ceramic quasibinary systems Ti1-x Zr x N, Ti1-x Hf x N and Zr1-x Hf x N (0 ⩽ x ⩽ 1) with density functional theory, cluster expansion and Monte Carlo simulations. We predict consolute temperatures (T C), at which miscibility gaps close, for Ti1-x Zr x N to be 1400 K, for Ti1-x Hf x N to be 700 K, and below 200 K for Zr1-x Hf x N. The asymmetry of the formation energy ΔE f(x) is greater for Ti1-x Hf x N than Ti1-x Zr x N, with less solubility on the smaller cation TiN-side, and similar asymmetries were predicted for the corresponding phase diagrams. We also analyzed different energetic contributions: ΔE f of the random solid solutions were decomposed into a volume change term, [Formula: see text], and a chemical exchange and relaxation term, [Formula: see text]. These two energies partially cancel one another. We conclude that [Formula: see text] influences the magnitude of T C and [Formula: see text] influences the asymmetry of ΔE f(x) and phase boundaries. We also conclude that the absence of experimentally observed phase separation in Ti1-x Zr x N and Ti1-x Hf x N is due to slow kinetics at low temperatures. In addition, elastic constants and mechanical properties of the random solid solutions were studied with the special quasirandom solution approach. Monotonic trends, in the composition dependence, of shear-related mechanical properties, such as Vickers hardness between 18 to 23 GPa, were predicted. Trends for Ti1-x Zr x N and Ti1-x Hf x N exhibit down-bowing (convexity). It shows that mixing nitrides of same group transition metals does not lead to hardness increase from an electronic origin, but through solution hardening mechanism. The mixed thin films show consistency and stability with little phase separation, making them desirable coating choices.

Within-population Y-linked genetic variation for lifespan in Drosophila melanogaster.

The view that the Y chromosome is of little importance for phenotypic evolution stems from early studies of Drosophila melanogaster. This species' Y chromosome contains only 13 protein-coding genes, is almost entirely heterochromatic and is not necessary for male viability. Population genetic theory further suggests that non-neutral variation can only be maintained at the Y chromosome under special circumstances. Yet, recent studies suggest that the D. melanogaster Y chromosome trans-regulates hundreds to thousands of X and autosomal genes. This finding suggests that the Y chromosome may play a far more active role in adaptive evolution than has previously been assumed. To evaluate the potential for the Y chromosome to contribute to phenotypic evolution from standing genetic variation, we test for Y-linked variation in lifespan within a population of D. melanogaster. Assessing variation for lifespan provides a powerful test because lifespan (i) shows sexual dimorphism, which the Y is primarily predicted to contribute to, (ii) is influenced by many genes, which provides the Y with many potential regulatory targets and (iii) is sensitive to heterochromatin remodelling, a mechanism through which the Y chromosome is believed to regulate gene expression. Our results show a small but significant effect of the Y chromosome and thus suggest that the Y chromosome has the potential to respond to selection from standing genetic variation. Despite its small effect size, Y-linked variation may still be important, in particular when evolution of sexual dimorphism is genetically constrained elsewhere in the genome.

Lack of parvalbumin in mice leads to behavioral deficits relevant to all human autism core symptoms and related neural morphofunctional abnormalities.

Gene mutations and gene copy number variants are associated with autism spectrum disorders (ASDs). Affected gene products are often part of signaling networks implicated in synapse formation and/or function leading to alterations in the excitation/inhibition (E/I) balance. Although the network of parvalbumin (PV)-expressing interneurons has gained particular attention in ASD, little is known on PV's putative role with respect to ASD. Genetic mouse models represent powerful translational tools for studying the role of genetic and neurobiological factors underlying ASD. Here, we report that PV knockout mice (PV(-/-)) display behavioral phenotypes with relevance to all three core symptoms present in human ASD patients: abnormal reciprocal social interactions, impairments in communication and repetitive and stereotyped patterns of behavior. PV-depleted mice also showed several signs of ASD-associated comorbidities, such as reduced pain sensitivity and startle responses yet increased seizure susceptibility, whereas no evidence for behavioral phenotypes with relevance to anxiety, depression and schizophrenia was obtained. Reduced social interactions and communication were also observed in heterozygous (PV(+/-)) mice characterized by lower PV expression levels, indicating that merely a decrease in PV levels might be sufficient to elicit core ASD-like deficits. Structural magnetic resonance imaging measurements in PV(-/-) and PV(+/-) mice further revealed ASD-associated developmental neuroanatomical changes, including transient cortical hypertrophy and cerebellar hypoplasia. Electrophysiological experiments finally demonstrated that the E/I balance in these mice is altered by modification of both inhibitory and excitatory synaptic transmission. On the basis of the reported changes in PV expression patterns in several, mostly genetic rodent models of ASD, we propose that in these models downregulation of PV might represent one of the points of convergence, thus providing a common link between apparently unrelated ASD-associated synapse structure/function phenotypes.

Assessment of everyday executive functioning in children with frontal or temporal epilepsies.

Executive functions are particularly vulnerable in case of brain disruption during childhood, when the brain is not fully mature. Some studies showed impairments of executive functions in children with epilepsy, but only a few of them investigated the impact of executive dysfunctions on daily life. The aim of this study was to understand the everyday executive functioning of children with epilepsy both at home and in school. We administered the Behavior Rating Inventory of Executive Function to parents and teachers of 53 children (7-16 years of age) with structural epilepsies or epilepsies of unknown cause of temporal lobe (n=25) or frontal lobe (n=28). The results indicated a global executive impairment in the whole group of patients, compared with normative data, with no difference between the group with temporal lobe epilepsy (TLE) and that with frontal lobe epilepsy (FLE), except for monitor domain, which seemed more frequently impaired in the group with FLE. Congruence between parent and teacher ratings was found. The frequency of seizures was not related to executive dysfunction, whereas the number of antiepileptic drugs tended to positively correlate with working memory impairment. Onset of epilepsy at a younger age was also related to more executive difficulties but only according to teacher ratings. Lastly, duration of epilepsy was strongly associated with executive deficits reported in the context of school. Our results support the executive dysfunction hypothesis in daily life of children with structural focal epilepsy or focal epilepsy of unknown cause and are consistent with the early brain vulnerability hypothesis currently prevalent in the context of child neuropsychology. The BRIEF appears to be a clinically useful tool for assessing executive function impairment in this clinical population.

Structural, mechanical and electronic properties of 3d transition metal nitrides in cubic zincblende, rocksalt and cesium chloride structures: a first-principles investigation.

We report systematic results from ab initio calculations with density functional theory on three cubic structures, zincblende (zb), rocksalt (rs) and cesium chloride (cc), of the ten 3d transition metal nitrides. We computed lattice constants, elastic constants, their derived moduli and ratios that characterize mechanical properties. Experimental measurements exist in the literature of lattice constants for rs-ScN, rs-TiN and rs-VN and of elastic constants for rs-TiN and rs-VN, all of which are in good agreement with our computational results. Similarly, computed Vickers hardness (HV) values for rs-TiN and rs-VN are consistent with earlier experimental results. Several trends were observed in our rich data set of 30 compounds. All nitrides, except for zb-CrN, rs-MnN, rs-FeN, cc-ScN, cc-CrN, cc-NiN and cc-ZnN, were found to be mechanically stable. A clear correlation in the atomic density with the bulk modulus (B) was observed with maximum values of B around FeN, MnN and CrN. The shear modulus, Young's modulus, HV and indicators of brittleness showed similar trends and all showed maxima for cc-VN. The calculated value of HV for cc-VN was about 30 GPa, while the next highest values were for rs-ScN and rs-TiN, about 24 GPa. A relation (H(V) is proportional to θ(D)(2)) between HV and Debye temperature (θD) was investigated and verified for each structure type. A tendency for anti-correlation of the elastic constant C44, which strongly influences stability and hardness, with the number of electronic states around the Fermi energy was observed.

Cognitive inhibition and quality of life in schizophrenia: a pilot study.

AIM: To compare cognitive inhibition and quality of life in patients with schizophrenia and healthy controls. METHODS: Ten patients with schizophrenia were compared to 10 healthy controls, matched for age, sex, and educational level. Cognitive inhibition was examined by: 1) access to relevant information (Reading with distraction task), 2) suppression of no longer relevant information (Trail Making Test), and 3) restraint of cognitive resources to relevant information (Stroop Test, Hayling Sentence Completion Test, Go/No-Go Test). Montgomery Asberg Depression Rating Scale, Positive and Negative Syndrome Scale, and Schizophrenia-Quality of Life scale (S-QoL) were also used. RESULTS: Patients with schizophrenia showed a significant impairment in the suppression function of cognitive inhibition only, in comparison to the control group. Their access and restraint functions of cognitive inhibition were preserved. No relationship between quality of life and cognitive inhibition was found in patients with schizophrenia. CONCLUSIONS: During the stabilization phase of schizophrenia, the ability to inhibit neutral information access to working memory, and to restrain and suppress irrelevant information may not impair the patient's capacity to respond adequately to stressful situations, and thus would do not impact their quality of life.

Control of neuronal excitability by calcium binding proteins: a new mathematical model for striatal fast-spiking interneurons.

Calcium binding proteins, such as parvalbumin (PV), are abundantly expressed in distinctive patterns in the central nervous system but their physiological function remains poorly understood. Notably, at the level of the striatum, where PV is only expressed in the fast-spiking (FS) interneurons. FS interneurons form an inhibitory network modulating the output of the striatum by synchronizing medium-sized spiny neurons (MSN). So far the existing conductance-based computational models for FS neurons did not allow the study of the coupling between PV concentration and electrical activity. In the present paper, we propose a new mathematical model for the striatal FS interneurons that includes apamin-sensitive small conductance Ca(2+)-dependent K(+) channels (SK) and the presence of a calcium buffer. Our results show that a variation in the concentration of PV can modulate substantially the intrinsic excitability of the FS interneurons and therefore may be involved in the information processing at the striatal level.

Deficit of cognitive inhibition in depressed elderly: a neurocognitive marker of suicidal risk.

BACKGROUND: Cognitive deficits, in relation to ventral and dorsal prefrontal cortex dysfunctions, have been associated with a higher risk of suicidal acts in young adult patients. Although a public health concern, much less is known about the neurocognitive basis of suicidal behavior in elderly. Here, we aimed at assessing alterations in cognitive inhibition, a suspected major mechanism of the suicidal vulnerability, in suicidal depressed elderly. METHODS: We compared 20 currently depressed patients, aged 65 and older who recently attempted suicide to 20 elderly subjects with a current depression but no personal history of suicide attempt and 20 elderly controls. Using an extensive neuropsychological battery, we particularly examined different aspects of cognitive inhibition: access to relevant information (using the Reading with distraction task), suppression of no longer relevant information (Trail Making Test, Rule Shift Cards), and restraint of cognitive resources to relevant information (Stroop test, Hayling Sentence Completion test, Go/No-Go). RESULTS: After adjustment for age, intensity of depression, Mini-Mental State Examination score and speed of information processing, suicidal depressed elderly showed significant impairments in all 3 domains of cognitive inhibition in comparison to both control groups. LIMITATIONS: Our results need replication in a larger sample size. CONCLUSIONS: Our study suggests that the inability to inhibit neutral information access to working memory, restrain and delete irrelevant information may impair the patient's capacity to respond adequately to stressful situations subsequently leading to an increased risk of suicidal behavior during late-life depression. Interventions may be developed to specifically target cognitive impairment in the prevention of suicide in depressed elderly.

Detection of pulsed gamma rays above 100 GeV from the Crab pulsar.

We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.

A contribution to the study of environmental dependency phenomena: the social hypothesis.

Environmental dependency phenomena refer to the symptoms initially described by Lhermitte (1983, 1984) under the terms of "utilization behavior" and "imitation behavior". These clinical signs are linked to essential notions such as free-will and human autonomy, and seem to be specific of the frontal pathology. Surprisingly, few studies have addressed these symptoms and inconsistent definitions are available. To investigate the theoretical and clinical definitions of environmental dependency phenomena, three groups of neurological patients (n=60) with frontal, subcortical, and posterior brain lesions were compared. Clinically, our findings help to rehabilitate the definitions of Lhermitte (1983, 1984) and challenge the classical interpretation in terms of an executive control deficit. The frontal specificity of the disorders and the lack of relation between executive/behavioral deficits were supported. The right orbitofrontal cortex seems particularly involved in environmental dependency. These results offer some evidences for differentiate two historical concepts of neuropsychology, namely the "frontal" and "dysexecutive" syndromes. A new interpretation of environmental dependency phenomena is provided which could be helpful to orient the neuropsychology of frontal syndrome.

Selective assembly of multi-component nanosprings and nanorods.

This communication proposes a new approach to create complex hierarchical nano-to-meso-scale architectures based on the use of biological connector molecules to direct the assembly of uniquely shaped multi-component nanostructures fabricated using glancing angle deposition (GLAD). Multiple sets of 50-nm-wide and 150 to 650-nm-tall Si-Cr/Au multi-stack zigzag nanosprings and nanorods are grown by GLAD on Si substrates. Nanorods, chosen for selective assembly, are detached from the substrate, suspended in an aqueous solution, and their surfaces are selectively functionalized by attaching biotin and streptavidin connector-molecules to the Au-regions. Successive mixing of different suspensions leads to the end-to-end assembly of long and short nanorods. This technique provides the path to build hybrid nano-architectures including nano-honeycombs, nanoladders, and 3D nanorod networks, comprised of controlled material combinations.

Utilization behavior: clinical and theoretical approaches.

Lhermitte (1983) coined the term "utilization behavior" (UB) to define a neurobehavioral syndrome in which the visuo-tactile presentation of objects compels patients to grasp and use them, despite the fact that they have not been instructed to do so. The author suggested that UB was the consequence of frontal lobe damage. Thereafter, Shallice, Burgess, Schon, and Baxter (1989) questioned Lhermitte's (1983) procedure for eliciting UB, putting forward an alternative research methodology that led to differentiate two forms of UB: "induced" and "incidental." To date, there has been no direct comparison between these two procedures, nor have any other methodologies been used to explore this clinical sign, which is related to fundamental concepts such as free will and human autonomy. We investigated UB in 70 subjects (25 patients with frontal lobe lesions, 10 patients with posterior brain damage and 35 control subjects) using the methodologies of Lhermitte (1983) and Shallice et al. (1989), as well as an original "verbal generation" procedure. Our results show that the verbal generation procedure reveals UB efficiently and that elicitation of this sign appears to be directly linked to the content of the task. We discuss the interpretation of UB in terms of an executive control deficit.

Radio imaging of the very-high-energy gamma-ray emission region in the central engine of a radio galaxy.

The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.