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Mdm2 and MdmX are related proteins serving in the form of the Mdm2 homodimer or Mdm2/MdmX heterodimer as an E3 ubiquitin ligase for the tumor suppressor p53. The dimerization is required for the E3 activity and is mediated by the conserved RING domains present in both proteins, but only the RING domain of Mdm2 can form homodimers efficiently. We performed a systematic mutational analysis of human Mdm2, exchanging parts of the RING with the corresponding MdmX sequence, to identify the molecular determinants of this difference. Mdm2 can also promote MdmX degradation, and we identified several mutations blocking it. They were located mainly at the Mdm2/E2 interface and did not disrupt the MdmX-Mdm2 interaction. Surprisingly, some mutations of the Mdm2/E2 interface inhibited MdmX degradation, which is mediated by the Mdm2/MdmX heterodimer, but did not affect p53 degradation, mediated by the Mdm2 homodimer. Only one mutant, replacing a conserved cysteine 449 with asparagine (C449N), disrupted the ability of Mdm2 to dimerize with MdmX. When we introduced the cysteine residue into the corresponding site in MdmX, the RING domain became capable of forming dimers with other MdmX molecules in vivo , suggesting that one conserved amino acid residue in the RINGs of Mdm2 and MdmX could serve as the determinant of the differential ability of these domains to form dimers and their E3 activity. In immunoprecipitations, however, the homodimerization of MdmX could be observed only when the asparagine residue was replaced with cysteine in both RINGs. This result suggested that heterocomplexes consisting of one mutated MdmX RING with cysteine and one wild-type MdmX RING with asparagine might be less stable, despite being readily detectable in the cell-based assay. Moreover, Mdm2 C449N blocked Mdm2-MdmX heterodimerization but did not disrupt the ability of Mdm2 homodimer to promote p53 degradation, suggesting that the effect of the conserved cysteine and asparagine residues on dimerization was context-specific. Collectively, our results indicate that the effects of individual exchanges of conserved residues between Mdm2 and MdmX RING domains might be context-specific, supporting the hypothesis that Mdm2 RING homodimers and Mdm2-MdmX heterodimers may not be entirely structurally equivalent, despite their apparent similarity. [ABSTRACT FROM AUTHOR]

Highlights • Individual differences influence driving aggression. • Driving aggression causes accidents, unnecessary injury, and death. • Psychopathy, physical aggression, and impeded progress predict unsafe driving. • Personality’s influence on angry driving is fully mediated via aggression. • Driving instruction should include managing progress impedance-related anger. Abstract The present study tested the role of Dark Triad traits (DT; narcissism, psychopathy, and Machiavellianism) as potential contributors to self-reported aggressive driving alongside driving anger, general aggression, impulsiveness, and attributions of malign driving intent. Members of the general community (N = 168) completed an online survey battery measuring these characteristics, and a proxy measure of aggressive driving. Regression analyses revealed that psychopathy, a history of physical aggression towards others, and the “progress impeded” aspect of driving anger, accounted for 50.8% of the variance in self-reported aggressive driving behaviours. The remaining variables were not significant. A structural equation model found all measures fitted into a single model in which impulsivity and the DT predicted general aggression, general aggression fully mediated the effect of the DT on driving anger, and general aggression and progress impedance predicted self-reported aggressive driving (GFI = 0.925). These results indicate tendencies toward expressing aggression physically, frustration at goals being impeded, and a callous, impulsive nature can predispose an individual to aggressive driving behaviours. Implications of these findings and recommendations for research are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Bayesian structural equation modeling (BSEM) was used to investigate the latent structure of the Differential Ability Scales—Second Edition core battery using the standardization sample normative data for ages 7–17. Results revealed plausibility of a three‐factor model, consistent with publisher theory, expressed as either a higher‐order (HO) or a bifactor (BF) model. The results also revealed an alternative structure with the best model fit, a two‐factor BF model with Matrices (MA) and Sequential and Quantitative Reasoning (SQ) loading on g only with no respective group factor loading. This was only the second study to use BSEM to investigate the structure of a commercial ability test and the first to use a large normative sample and the specification of both approximate zero cross‐loadings and correlated residual terms. It is believed that the results produced from the current study will advance the field's understanding of not only the factor structure of the DAS‐II core battery but also the potential utility of BSEM in psychometric investigations of intelligence test structures. [ABSTRACT FROM AUTHOR]

In this work, we consider the Lamé system in 3-dimension bounded domain with distributed delay term. We prove, under some appropriate assumptions, that this system is well-posed and stable. Furthermore, the asymptotic stability is given by using an appropriate Lyapunov functional. [ABSTRACT FROM AUTHOR]

Recently emerging evidence suggests that the dominant structural model of mental abilities-the Cattell-Horn-Carroll (CHC) model-may not adequately account for observed scores for mental abilities batteries, leading scholars to call into question the model's validity. Establishing the robustness of these findings is important since CHC is the foundation for several contemporary mental abilities test batteries, such as the Woodcock-Johnson III (WJ-III). Using confirmatory factor analysis, we investigated CHC's robustness across 4 archival samples of mental abilities test battery data, including the WJ-III, the Kaufman Adolescent & Adult Intelligence Test (KAIT), the Kaufman Assessment Battery for Children (KABC), and the Differential Ability Scales (DAS). We computed omega hierarchical (ωH) and omega subscale (ωS) coefficients for g and the broad factors, which estimated the relationship of composite scores to g and the broad factors, respectively. Across all 4 samples, we found strong evidence for a general ability, g. We additionally found evidence for 3 to 9 residualized, orthogonal broad abilities existing independently of g, many of which also explained reliable variance in test battery scores that cannot be accounted for by g alone. The reliabilities of these broad factors, however, were less than desirable (i.e., <.80) and achieving desirable reliabilities would be practically infeasible (e.g., requiring excessively large numbers of subtests). Our results, and those of CHC critics, are wholly consistent with Carroll's model. Essentially, both g and orthogonal broad abilities are required to explain variance in mental abilities test battery scores, which is consistent with Carroll but not Cattell-Horn. (PsycINFO Database Record [ABSTRACT FROM AUTHOR]

The present study examined the factor structure of the Differential Ability Scales-Second Edition (DAS-II; Elliott, 2007a) standardization sample using exploratory factor analyses, multiple factor extraction criteria, and hierarchical exploratory factor analyses (Schmid & Leiman, 1957) not included in the DAS-II Introductory and Technical Handbook (Elliott, 2007b). Exploratory factor analyses with multiple factor extraction criteria and hierarchical analyses with the Schmid and Leiman (1957) procedure were conducted with the 3 DAS-II standardization samples (Lower Early Years [Ages 2:6-3:5], Upper Early Years [Ages 3:6-6:11], School-Age [Ages 7:0-17:11]). All factor extraction criteria suggested 1 factor despite the author and publisher recommended and promoted 2 (Ages 2:6-3:5) or 3 (Ages 3:6-6:11, Ages 7:0-17:11) factors. Results indicated that most DAS-II subtests were properly associated with the theoretically proposed first-order factors. Hierarchical exploratory analyses with the Schmid and Leiman procedure, however, found that the hierarchical g factor accounted for large portions of total and common variance, while the 2 or 3 first-order factors accounted for small portions of total and common variance. It was concluded that the DAS-II provides strong measurement of general intelligence but clinical interpretation should be primarily at that level. (PsycINFO Database Record [ABSTRACT FROM AUTHOR]

The Test of Visuospatial Construction (TVSC), a measure of visuoconstruction that does not rely on upper extremity motor response or written production, was administered to extremely low birth weight (ELBW), late preterm (LPT), and term participants at preschool (n = 355) and kindergarten (n = 265) ages. TVSC showed statistically significant weak-to-moderate positive correlations (age 3:r = .118–.303; age 6:r = .138–.348) with Developmental VMI, Differential Ability Scales-II Copying, Matrices, and Pattern Construction subtests, Baron-Hopkins Board Test, and the Purdue Pegboard. One-way ANOVA indicated ELBW performed worse than Term (p = .044) on visuospatial construction at age 3 with a small-to-medium effect size (d = −0.43). No other statistically significant differences were found at age 3 on the TVSC (ELBW/LPT:p = .608,d = −0.17; LPT/Term:p = .116,d = −0.31). At age 6, ELBW participants performed worse than LPT participants (p = .027) and Term participants (p = .012); LPT participants did not differ from Term participants. Small effect sizes at age 3 (ELBW < LPT,d = −0.17; ELBW < Term,d = −0.43) were notably larger at age 6 (ELBW < LPT,d = −0.42; ELBW < Term,d = −0.53). Important practical differences showing LPT participants performed below Term participants (d = −0.31) at age 3 were no longer evident at age 6 (d = −0.097). These findings provide preliminary evidence of TVSC validity supporting its use to detect neuropsychological impairment and to recommend appropriate interventions in young preterm children. [ABSTRACT FROM PUBLISHER]

Estimates of intelligence in young children with neurodevelopmental disorders are critical for making diagnoses, in characterizing symptoms of disorders, and in predicting future outcomes. The limitations of standardized testing for children with developmental delay or cognitive impairment are well known: Tests do not exist that provide developmentally appropriate material along with norms that extend to the lower reaches of ability. Two commonly used and interchanged instruments are the Mullen Scales of Early Learning (MSEL), a test of developmental level, and the Differential Ability Scales, second edition (DAS-II), a more traditional cognitive test. We evaluated the correspondence of contemporaneous MSEL and the DAS-II scores in a mixed sample of children aged 2–10 years with autism spectrum disorder (ASD), non-ASD developmental delays, and typically developing children across the full spectrum of cognitive ability. Consistent with published data on the original DAS and the MSEL, scores on the DAS-II and MSEL were highly correlated. However, curve estimation revealed large mean differences that varied as a function of the child’s cognitive ability level. We conclude that interchanging MSEL and DAS-II scores without regard to the discrepancy in scores may produce misleading results in both cross-sectional and longitudinal studies of children with and without ASD, and, thus, this practice should be implemented with caution. [ABSTRACT FROM PUBLISHER]

A low-temperature plasma (LTP) was used as an ionization source for differential ion mobility spectrometry (DMS) for the first time. This ionization source enhances the potential of DMS as a miniaturized system for on-site rapid monitoring. The effects of experimental parameters (e.g., discharge/carrier gas composition and flow rate, applied voltage) on the analysis of model aromatic compounds were investigated and discussed. It was found that the nature of reactant ion positive (RIP) is dependent on the discharge/ carrier gas composition. The best response to the analyte was achieved when pure nitrogen was used as the discharge/carrier gas. The ability to perform analysis with zero helium consumption is especially attractive in view of the potential application of LTP-DMS for online (and on-site) monitoring. Analytical performance was determined with six environmentally relevant model compounds (benzene, toluene, ethylbenzene, pxylene, 1,2,4-trimethylbenzene, and naphthalene) using LTP and directly compared to APPI and APCI (63Ni) ionization sources. When LTP was coupled to DMS, calculated LOD values were found to be in the range of 35-257 ng L-1 (concentration in the carrier gas). These values are competitive with those calculated for two DMS equipped with traditional ionization sources (APPI, 63Ni). The obtained results are promising enough to ensure the potential of LTP as ionization source for DMS. [ABSTRACT FROM AUTHOR]

Extant data suggest that the cognitive profiles of individuals with ASD may be characterized by variability, particularly in terms of verbal intellectual functioning (VIQ) and non-verbal intellectual functioning (NVIQ) discrepancies. The Differential Ability Scales, Second Edition (DAS-II) has limited data available on its use with youth with ASD. The current study examined data from 2,110 youth with ASD in order to characterize performance on the DAS-II and to investigate potential discrepancies between VIQ and NVIQ. A larger proportion of individuals in the ASD sample had significant discrepancies between VIQ and NVIQ when compared to the normative sample [early years sample χ (2) = 38.36; p < .001; school age sample χ (2) = 13.48; p < .01]. Clinical and research implications are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] We analyzed the associations of SES and cognitive enrichment with cognitive performance among children from an advantaged and a disadvantaged population. [•] Individual SES was associated with cognitive performance within advantaged and disadvantaged populations. [•] Child enrichment was associated with better cognitive performance and attenuated the SES influence. [Copyright &y& Elsevier]

Decades of research have examined the neurocognitive mechanisms of cognitive control, but the motivational factors underlying task selection and performance remain to be elucidated. We recently proposed that anterior cingulate cortex (ACC) utilizes reward prediction error signals carried by the midbrain dopamine system to learn the value of tasks according to the principles of hierarchical reinforcement learning. According to this position, disruption of the ACC-dopamine interface can disrupt the selection and execution of extended, task-related behaviors. To investigate this issue, we recorded the event-related brain potential (ERP) from children with attention deficit hyperactivity disorder (ADHD), which is strongly associated with ACC-dopamine dysfunction, and from typically developing children while they navigated a simple 'virtual T-maze' to find rewards. Depending on the condition, the feedback stimuli on each trial indicated that the children earned or failed to earn either money or points. We found that the reward positivity, an ERP component proposed to index the impact of dopamine-related reward signals on ACC, was significantly larger with money feedback than with points feedback for the children with ADHD, but not for the typically developing children. These results suggest that disruption of the ACC-dopamine interface may underlie the impairments in motivational control observed in childhood ADHD. [ABSTRACT FROM AUTHOR]

Growing evidence suggests that positive affect and reward have differential effects on cognitive control. So far, however, these effects have never been studied together. Here, the authors present one behavioral study investigating the influences of positive affect and reward (contingent and noncontingent) on proactive control. A modified version of the AX-continuous performance task, which has repeatedly been shown to be sensitive to reward and affect manipulations, was used. In a first phase, two experimental groups received either neutral or positive affective pictures before every trial. In a second phase, the two halves of a given affect group additionally received, respectively, performance-contingent or random rewards. The results replicated the typical affect effect, in terms of reduced proactive control under positive as compared to neutral affect. Also, the typical reward effects associated with increased proactive control were replicated. Most interestingly, performance-contingent reward counteracted the positive affect effect, whereas random reward mirrored that effect. In sum, this study provides first evidence that performance-contingent reward, on the one hand, and positive affect and performance-noncontingent reward, on the other hand, have oppositional effects on cognitive control: Only performance-contingent reward showed a motivational effect in terms of a strategy shift toward increased proactive control, whereas positive affect alone and performance-noncontingent reward reduced proactive control. Moreover, the integrative design of this study revealed the vulnerability of positive affect effects to motivational manipulations. The results are discussed with respect to current neuroscientific theories of the effects of dopamine on affect, reward, and cognitive control. [ABSTRACT FROM AUTHOR]

Background: To assess insight in a large sample of patients with schizophrenia and to study its relationship with set shifting as an executive function. Methods: The insight of a sample of 161 clinically stable, community-dwelling patients with schizophrenia was evaluated by means of the Scale to Assess Unawareness of Mental Disorder (SUMD). Set shifting was measured using the Trail-Making Test time required to complete part B minus the time required to complete part A (TMT B-A). Linear regression analyses were performed to investigate the relationships of TMT B-A with different dimensions of general insight. Results: Regression analyses revealed a significant association between TMT B-A and two of the SUMD general components: 'awareness of mental disorder' and 'awareness of the efficacy of treatment'. The 'awareness of social consequences' component was not significantly associated with set shifting. Conclusions: Our results show a significant relation between set shifting and insight, but not in the same manner for the different components of the SUMD general score. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Analyzing examinees' responses using cognitive diagnostic models (CDMs) has the advantage of providing diagnostic information. To ensure the validity of the results from these models, differential item functioning (DIF) in CDMs needs to be investigated. In this article, the Wald test is proposed to examine DIF in the context of CDMs. This study explored the effectiveness of the Wald test in detecting both uniform and nonuniform DIF in the DINA model through a simulation study. Results of this study suggest that for relatively discriminating items, the Wald test had Type I error rates close to the nominal level. Moreover, its viability was underscored by the medium to high power rates for most investigated DIF types when DIF size was large. Furthermore, the performance of the Wald test in detecting uniform DIF was compared to that of the traditional Mantel-Haenszel (MH) and SIBTEST procedures. The results of the comparison study showed that the Wald test was comparable to or outperformed the MH and SIBTEST procedures. Finally, the strengths and limitations of the proposed method and suggestions for future studies are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] CD56dim positive NK-cells, CD4+ and CD8+ subsets of activated T-cells were recognized by ficolin-1. [•] Neither NKT-cells, CD56bright positive NK-cells, B-cells nor resting T-cell were recognized by ficolin-1. [•] Interaction occurred through the pathogen-recognition domain of ficolin-1. [•] Ficolin-1 binds to living cells. [•] Sialic acid on the lymphocyte surface was the putative ligand for ficolin-1. [ABSTRACT FROM AUTHOR]

Highlights: [•] There are no significant differences in average scores between the Leiter-R and DAS-II. [•] ∼25% of children had meaningful intra-individual differences (>1SD) in assessments. [•] Differences in cognitive ability classification did occur in a subset. [•] Hearing loss severity did not contribute to IQ scores on scores or score differences. [•] Verbal IQ tests are often auditorily administered highlighting importance of nonverbal tests. [Copyright &y& Elsevier]

For some authors, the human sensitivity to numerosities would be grounded in our ability to process non-numerical magnitudes. In the present study, the developmental relationships between non numerical and numerical magnitude processing are examined in people with Williams syndrome (WS), a genetic disorder known to associate visuo-spatial and math learning disabilities. Twenty patients with WS and 40 typically developing children matched on verbal or non-verbal abilities were administered three comparison tasks in which they had to compare numerosities, lengths or durations. Participants with WS showed lower acuity (manifested by a higher Weber fraction) than their verbal matched peers when processing numerical and spatial but not temporal magnitudes, indicating that they do not present a domain-general dysfunction of all magnitude processing. Conversely, they do not differ from non-verbal matched participants in any of the three tasks. Finally, correlational analyses revealed that non-numerical and numerical acuity indexes were both related to the first mathematical acquisitions but not with later arithmetical skills. [ABSTRACT FROM AUTHOR]

The linear loadings of intelligence test composite scores on a general factor (g) have been investigated recently in factor analytic studies. Spearman's law of diminishing returns (SLODR), however, implies that the g loadings of test scores likely decrease in magnitude as g increases, or they are nonlinear. The purpose of this study was to (a) investigate whether the g loadings of composite scores from the Differential Ability Scales (2nd ed.) (DAS-II, C. D. Elliott, 2007a, Differential Ability Scales (2nd ed.). San Antonio, TX: Pearson) were nonlinear and (b) if they were nonlinear, to compare them with linear g loadings to demonstrate how SLODR alters the interpretation of these loadings. Linear and nonlinear confirmatory factor analysis (CFA) models were used to model Nonverbal Reasoning, Verbal Ability, Visual Spatial Ability, Working Memory, and Processing Speed composite scores in four age groups (5-6, 7-8, 9-13, and 14-17) from the DAS-II norming sample. The nonlinear CFA models provided better fit to the data than did the linear models. In support of SLODR, estimates obtained from the nonlinear CFAs indicated that g loadings decreased as g level increased. The nonlinear portion for the nonverbal reasoning loading, however, was not statistically significant across the age groups. Knowledge of general ability level informs composite score interpretation because g is less likely to produce differences, or is measured less, in those scores at higher g levels. One implication is that it may be more important to examine the pattern of specific abilities at higher general ability levels. [ABSTRACT FROM AUTHOR]

Synaptic transmission depends on the matching and alignment of presynaptically released transmitters and postsynaptic neurotrans-mitter receptors. Neuroligin (NL) and Neurexin (Nrxn) proteins are frans-synaptic adhesion molecules that are important in validation and maturation of specific synapses. NL isoforms NL1 and NL2 have specific functional roles in excitatory and inhibitory synapses, respectively, but the molecular basis behind this distinction is still unclear. We show here that the extracellular domain of NL2 confers its unique ability to enhance inhibitory synaptic function when overexpressed in rat hippocampal pyramidal neurons, whereas NL1 normally only promotes excitatory synapses. This specificity is conferred by presynaptic Nrxn isoforms, as NL1 can also induce functional inhibitory synapse connections when the presynaptic interneurons ectopically express an Nrxn isoform that binds to NL1. Our results indicate that trans-synaptic interaction with differentially expressed presynaptic Nrxns underlies the distinct functions of NL1 and NL2, and is sufficient to induce functional inhibitory synapse formation. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: The aims for this study were to determine the prevalence of sleep-bruxism among young children, explore child behavior problems that may be associated with sleep-bruxism, and identify relations among sleep-bruxism, health problems, and neurocognitive performance. Methods: The current study was a retrospective analysis of parent report surveys, and behavioral and neurocognitive assessments. Parents of 1953 preschool and 2888 first grade children indicated their child’s frequency of bruxism during sleep. A subsample of preschool children (n =249) had additional behavioral, as well as neurocognitive assessments. Among the subsample, parents also reported on their child’s health, and completed the Child Behavioral Checklist; children were administered the Differential Ability Scales, and Pre-Reading Abilities subtests of the Developmental Neuropsychological Assessment. Results: 36.8% of preschoolers and 49.6% of first graders were reported to brux ⩾1time per week. Among the preschool subsample, bruxing was independently associated with increased internalizing behaviors (β =.17). Bruxism was also associated with increased health problems (β =.19), and increased health problems were associated with decreased neurocognitive performance (β =.22). Conclusions: The prevalence of sleep-bruxism was high. A dynamic and potentially clinically relevant relation exists among sleep-bruxism, internalizing behaviors, health, and neurocognition. Pediatric sleep-bruxism may serve as a sentinel marker for possible adverse health conditions, and signal a need for early intervention. These results support the need for an interdisciplinary approach to pediatric sleep medicine, dentistry, and psychology. [Copyright &y& Elsevier]

With a sample of 194 adults, approximately half of which were involuntarily unemployed, the present study explored (a) how calling related to core self-evaluations and life satisfaction, (b) whether core self-evaluations mediated the relation of calling to life satisfaction, and (c) how these relations differed for employed/voluntarily unemployed and involuntarily unemployed adults. Mediation analyses among the three variables were tested for each group. For both groups, calling was a significant, moderate predictor of core self-evaluations. Further, core self-evaluations was found to fully mediate in the link between calling and life satisfaction among the involuntarily unemployed group and partially mediate this relation among the employed/voluntarily unemployed group. The results of the present study suggest that higher levels of calling (regardless of employment status) relates to life satisfaction via a more positive sense of self. For the employed/voluntarily unemployed group, there may be benefits of a calling beyond positive self-evaluations. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Tissue factor (TF), the primary initiator of coagulation in vivo, plays a major role in both thrombosis and hemostasis. The expression of TF in monocytes is well documented, but its presence in other blood cells has been disputed, possibly due to methodological variations among different studies. Materials and methods: We studied TF expression on platelets, monocytes, lymphocytes and microparticles (MPs) by flow cytometry (FCM) with five commercially available mouse anti-human TF antibodies (HTF-1, TF9-10H10, CLB/TF-5, VIC7 and VD8). The ability of different TF antibodies to inhibit cell surface TF activity was explored by incubating LPS-stimulated monocytes and MPs derived from LPS-stimulated monocytes (MMPs) with TF antibodies followed by measuring TF activity. Results: HTF-1 detected TF only on LPS-stimulated monocytes, whereas, TF9-10H10 and VD8 detected TF associated with MPs and MMPs in addition to LPS stimulated monocytes. Surprisingly, CLB/TF-5 and VIC7 detected TF on platelets, monocytes even under unstimulated conditions, in addition to MPs and MMPs. CLB/TF-5 also detected TF on unstimulated lymphocytes. Inhibitory studies showed that at a final concentration of 10μg/mL, HTF-1, CLB/TF-5 and VD8 inhibited monocyte TF activity by 81-84% and MMP TF activity by 92-96%; whereas TF9-10H10 had no inhibitory effect on TF activity in monocytes and MMPs. Conclusions: Our results suggest non-specific binding by the CLB/TF-5 and VIC7 antibodies in a FCM test system and explain at least some of the reports on TF presence in blood cells, particularly TF associated with platelets and MPs. TF9-10H10 and VD8 are more suitable to detect TF on MPs by FCM. [Copyright &y& Elsevier]

Spearman's law of diminishing returns (SLODR) refers to the diminishing influence of g at higher g levels. In this study, we used factor mixture modeling to investigate SLODR in the Differential Ability Scales--2nd Edition (DAS-II). Evidence of SLODR was found. The mean and covariance structure among DAS-II subtests were best described by a 2-class confirmatory factor model with class-specific g means, Gf-specific variance (although evidence was mixed), g variance, and subtest residual variance. Higher levels of g were characterized by less g factor variance, and standardized g loadings decreased at higher ability levels. Interpretative weight of IQ composite and subtest scores may depend on the level of g. [ABSTRACT FROM AUTHOR]

Abstract: Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these differences across age. Most broad abilities showed mean differences across the sexes, and all such differences varied across ages. Girls showed an advantage on the processing speed (Gs) first-order residual factor. Girls also showed advantages at some ages on free-recall memory, a narrow ability of long term retrieval (Glr). Boys showed a developmentally-related advantage on a visual–spatial ability (Gv) first-order residual factor, depending on age. Younger girls showed an advantage on short-term memory (Gsm). No statistically significant sex differences were shown on the latent comprehension-knowledge (Gc) factor, or on a second-order, latent g factor. Boys showed larger variances for several broad abilities, some substantial, but those differences were not statistically significant. [Copyright &y& Elsevier]

The purpose of this study was to investigate the g loadings and specific effects of the core and diagnostic composite scores from the Differential Abilities Scales, Second Edition (DAS-II; Elliott, 2007a). Scores from a subset of the DAS-II standardization sample for ages 3:6 to 17:11 were submitted to principal factor analysis. Four composites, Nonverbal Reasoning Ability, Verbal Ability, Spatial Ability, and Working Memory, appear to be primarily measures of the general factor across most age levels. In contrast, Processing Speed appears to primarily be a measure of a specific ability or specific abilities across age levels. A secondary analysis revealed that averaging subtest g loadings produced downwardly biased values for composites, that the Spearman (1927) formula for determining the g loading of a composite produced upwardly biased values, and that averaging subtest specific effects produced upwardly biased values for composites. [ABSTRACT FROM AUTHOR]

Investigations of differential item functioning (DIF) have been conducted mostly on ability tests and have found little evidence of easily interpretable differences across various demographic subgroups. In this study, we examined the degree to which DIF in biographical data items referencing academically relevant background, experiences, and interests was related to differences in judgments about access to these experiences by members of different gender and race subgroups. DIF in the location parameter was significantly related (r = -.51, p < .01) to gender differences in perceived accessibility to experience. No significant relationships with accessibility were observed for DIF in the slope parameter across gender groups or for the slope and location parameters associated with DIF across Black and White groups. Practical implications for use of biodata and theoretical implications for DIF research are discussed. [ABSTRACT FROM AUTHOR]

The recently published second edition of the Differential Abilities Scale (DAS-II) is designed to measure multiple broad and general abilities from Cattell–Horn–Carroll (CHC) theory. Although the technical manual presents information supporting the test's structure, additional research is needed to determine the constructs measured by the test and the consistency of measurement across ages. The purposes of this research were to determine whether the DAS-II measures the CHC abilities it is designed to measure and whether it does so consistently across the 4 to 17 year age span. We analyzed competing higher-order CFA models using 800 participants, ages 5 through 8, from the DAS-II standardization. The final validation model from this series of analyses tested for factor invariance across the 4 to 17 year age span by using a reference variable approach. Our findings supported the DAS-II's intended structure, with minor exceptions. Findings also supported the invariance of the DAS-II CHC model across the 4 to 17 year age span, again with minor exceptions. Despite the use of different tests at different ages, the DAS-II measures a consistent set of CHC abilities across the ages: g, Gc, Gf, Gv, Gsm, Gs, and a narrow Glr ability; psychologists should interpret the DAS-II as measuring these abilities. © 2010 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

This study investigated the effects of broad cognitive abilities derived from the Cattell–Horn–Carroll (CHC) taxonomy, together with the effect of the general factor (g), on Wechsler Individual Achievement Test, Second Edition (WIAT-II) reading achievement. Structural equation modeling (SEM) and commonality analyses were applied to the Differential Ability Scales, Second Edition (DAS-II) standardization and clinical sample data. All seven DAS-II CHC broad cognitive abilities were shown to have significant effects on one or more WIAT-II reading domains with different patterns found across typical, poor reader, and reading specific learning disability (SLD) groups. In the SEM analyses, the general factor g had only indirect effects on reading achievement variance. In the commonality analyses, after the effects of the seven CHC factors had been accounted for, the six-factor commonality—which could be considered an alternative measure of global intelligence—accounted for only 1%–2% of reading measure variance. For children who are having difficulties with reading skill acquisition, the data suggest that primary emphasis on g will result in a major loss of DAS-II predictive validity. Results emphasize the importance of having a comprehensive cognitive assessment with the DAS-II in the evaluation of reading competency and disability. Links between CHC broad ability factors and neuropsychological constructs may provide a promising foundation for developing specific cognitive, academic, and behavioral interventions for children with reading SLD. © 2010 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Despite growing interest in the role of personality in the prediction of aggression, few studies have taken a comprehensive approach to the issue. To assess effects of personality on aggression, we compared measures of the Five-Factor Model (FFM), behavioral inhibition/activation, and impulsivity traits across conditions (Equal or Differential ability to harm). Participants (N =137) competed in an aggression task wherein they received shocks and were able to shock their opponent who they believed had either identical or higher shocks at his/her disposal. Across conditions, FFM Antagonism, and Drive predicted aggression, whereas Extraversion was related to aggression only for men in the Differential condition. Surprisingly, the impulsivity traits and Neuroticism were largely unrelated to aggression. The importance of trait perspectives to understanding aggression is discussed. [Copyright &y& Elsevier]

Differential Item Functioning (DIF) is a widely used term in test development literature. It is very important to analyze test's data for DIF because It is a serious threat to validity. If the same data matrix was transposed, similar analysis can be carried for Differential Person Functioning (DPF). The purpose of this paper is to introduce and encourage the use of DPF analysis in tests of emotional or cognitive intelligence as a diagnostic approach through two examples illustrating the presence of DPF. [ABSTRACT FROM AUTHOR]

Background. In preschool and primary education, pupils differ in many abilities and competences (giftedness). Yet mainstream educational practice seems rather homogeneous in providing age-based or grade—class subject matter approaches. Aims. To clarify whether pupils scoring initially at high ability level do develop and attain differently at school with respect to language and arithmetic compared with those displaying other initial ability levels. To investigate whether specific individual, family, or educational variables covary with the attainment of these different types of pupils in school. Samples. Data from the large-scale PRIMA cohort study including a total of 8,258 Grades 2 and 4 pupils from 438 primary schools in The Netherlands. Methods. Secondary analyses were carried out to construct gain scores for both language and arithmetic proficiency and a number of behavioural, attitudinal, family, and educational characteristics. The pupils were grouped into four different ability categories (highly able, able, above average, average or below average). Further analyses used Pearson correlations and analyses of variance both between- and within-ability categories. Cross-validation was done by introducing a cohort of younger pupils in preschool and grouping both cohorts into decile groups based on initial ability in language and arithmetic. Results. Highly able pupils generally decreased in attainment in both language and arithmetic, whereas pupils in average and below-average groups improved their language and arithmetic scores. Only with highly able pupils were some educational characteristics correlated with the pupils' development in achievement, behaviour, and attitudes. Conclusions. Preschool and primary education should better match pupils' differences in abilities and competences from their start in preschool to improve their functioning, learning processes, and outcomes. Recommendations for educational improvement strategies are presented at the end of the article. [ABSTRACT FROM AUTHOR]

Using data from the PISA 2006 field trial, Rasch item response models are used to demonstrate that extreme response tendency was exhibited differentially across culturally distinct countries when answering Likert type attitude items. A single attitude scale is examined across eight culturally distinct countries in this paper. Two avenues to ameliorate this tendency are explored: first using dichotomous variants of the items, and second incorporating the country specific response tendency into the Rasch item response model. Analysis of the item variants reveals similar scale outcomes and correlations with achievement but preference for the Likert variant when test information is considered. A hierarchical analysis using facet models reveals that the data fit significantly better in a model that incorporates an interaction effect between the country and the item delta parameters. The implications for reporting attitudes measured with Likert items across cultures are outlined. [ABSTRACT FROM AUTHOR]

Oshima, Raju, Flowers, and Slinde (1998) described procedures for identifying sources of differential functioning for dichotomous data using differential bundle functioning (DBF) derived from the differential functioning of items and test (DFIT) framework (Raju, van der Linden, & Fleer, 1995). The purpose of this study was to extend the procedures for dichotomous DBF to the polytomous case and to illustrate how DBF analysis can be conducted with polytomous scoring, common to psychological and educational rating scales. The data set used was parent and teacher ratings of child problem behaviors. Three group contrasts (teacher vs. parent, boy vs. girl, and random groups) and two bundle organizing principles (subscale designation and random selection) were used for the DBF analysis. Interpretations of bundle indexes in the context of child problem behaviors were presented. [ABSTRACT FROM AUTHOR]

This study examined the underlying constructs measured by the Differential Ability Scales (DAS; C.D. Elliott, 1990a) as they relate to the Cattell-Horn-Carroll (CHC) Theory (K.S. McGrew, 1997) of cognitive abilities. The DAS and Woodcock-Johnson Tests of Cognitive Abilities (WJ-III COG; R.W. Woodcock, K.S. McGrew, & N. Mather, 2001) were administered to 131 children in grades 3 through 5 who took part in a concurrent validity study included in the Woodcock-Johnson Tests of Cognitive Abilities, Third Edition, technical manual (K.S. McGrew & R.W. Woodcock, 2001). Confirmatory factor analyses using maximum likelihood estimation were conducted with the AMOS 5.0 (J.L. Arbuckle, 2001) statistical program to evaluate three models of increasing complexity, to compare how well each fit the data set, and to identify the one that best described the underlying constructs measured by the DAS. Results suggested that the synthesized Three-Stratum CHC Model provided the most parsimonious representation among the three models tested. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 119–138, 2007. [ABSTRACT FROM AUTHOR]

We examined the association of proximal and distal training gain to subsequent menial status ratings in 302 participants (M = 76.62 years) trained on inductive reasoning or spatial orientation in the Seattle Longitudinal Study. Only training effects on reasoning ability were predictive of menial status group membership. Participants subsequently rated as probably demented did not significantly differ from nondemented participants in magnitude of reasoning training gain 14 years prior to assessment, but they did 7 years prior to status ratings. Proximal training gain 1 year prior to assessment was 0.40 SD for nondemented participants, compared with 0.25 and 0.10 SD for at-risk and probably demented participants, respectively. The combination of reasoning ability training and increased proximal training gain on reasoning ability was associated with a decreased likelihood of being rated as probably demented. [ABSTRACT FROM AUTHOR]

The present study was designed as an initial exploration of the relationship between global cognitive functioning and organizational and accuracy scores on the Rey-Osterrieth Complex Figure (ROCF) in a sample of children and adolescents. The relationship between ROCF accuracy scores at Copy and Delay as well as Organization and the Differential Ability Scales (DAS) was examined. Results indicate moderate correlations between Copy and Delay ROCF scores and various DAS indicators of nonverbal problem solving and visuospatial processing. Contrary to expectations, organizational scores were not significantly correlated with any of the DAS subscales or composite scales. Although further research is needed to explore the validity of this organizational scoring scheme with younger patients, these findings suggest that organization of the ROCF may be generally unrelated to global measures of cognitive ability or may assess processes associated with executive functioning untapped by the DAS. [ABSTRACT FROM AUTHOR]

The article discusses various issues related to Differential item functioning (DIF) detection and interpretation in large-scale science assessments. DIF analyses area routine part of the development of large-scale assessments. Less common are studies to understand the potential sources of DIF. The goals of this study were (a) to identify gender DIF in a large-scale science assessment and (b) to look for trends in the DIF and non-DIF items due to content, cognitive demands, item type, item text, and visual-spatial or reference factors.

This paper describes the procedures that can be used by school professionals to translate the directions of a test from one language (English) to another (Spanish). The procedures were then applied to the translation of four nonverbal Differential Ability Scale subtests into Spanish. The translation of these directions is provided in an appendix. The performance of a referred population of 97 Spanish speaking children, who were given the translated directions, mirrors that of children in the DAS standardization sample. Evidence from internal validity coefficients, concurrent validity coefficients, and construct validity suggests that the DAS nonverbal subtests can be translated and yield information comparable to non-translation. The translation provided makes possible a more standard administration of this test to Spanish-speaking children. [ABSTRACT FROM AUTHOR]

Asserts that credibility researchers have been too concerned with factor analyses of semantic differential scales. Aspects of factor analysis of credibility; Scale selection and factor naming; Overuse of the semantic differential.

Recognition tests are ubiquitous in the study of cognition. A simple index of recognition with desirable properties is the proportion R of targets preferred to distractors. The estimation of R by either a rating or a ranking method is straightforward. No distributional assumptions are involved. Three experiments are described in which estimates derived by the two methods were found to be close. The rating method is potentially subject to a bias. A preliminary account is given of calculations which suggest that the bias is small provided at least four rating categories are used. [ABSTRACT FROM AUTHOR]

The article presents a study which sought to relate scores obtained early in high school, the Differential Aptitude Tests (DAT), with the later academic success in college. The study has noted that the scores on the DAT obtained at the high school freshman level offer the high school counselor useful information in assessing the advisability of higher education for the student. It has showed that certain of the tests, specially those involving verbal and numerical skills, were better predictors of college success than others. This study approaches the problem of prediction of general college success and success in different college curricula longitudinally.

The differential allocation hypothesis predicts increased investment in offspring when females mate with high-quality males. Few studies have tested whether investment varies with mate relatedness, despite evidence that non-additive gene action influences mate and offspring genetic quality. We tested whether female lekking lance-tailed manakins (Chiroxiphia lanceolata) adjust offspring sex and egg volume in response to mate attractiveness (annual reproductive success, ARS), heterozygosity and relatedness. Across 968 offspring, the probability of being male decreased with increasing parental relatedness but not father ARS or heterozygosity. This correlation tended to diminish with increasing lay-date. Across 162 offspring, egg volume correlated negatively with parental relatedness and varied with lay-date, but was unrelated to father ARS or heterozygosity. Offspring sex and egg size were unrelated to maternal age. Comparisons of maternal half-siblings in broods with no mortality produced similar results, indicating differential allocation rather than covariation between female quality and relatedness or sex-specific inbreeding depression in survival. As males suffer greater inbreeding depression, overproducing females after mating with related males may reduce fitness costs of inbreeding in a system with no inbreeding avoidance, while biasing the sex of outbred offspring towards males may maximize fitness via increased mating success of outbred sons. [ABSTRACT FROM AUTHOR]

Background:The phenomenon of change blindness may reflect the failure to detect the presence of change or the absence of change. Although performing the latter is considered more difficult than the former, the differential functioning of retrieval/comparison processing that leads to differences between the detection of the presence and the absence of change has not been clarified. This study aimed to fill this research gap by comparing performance in the detection of the presence and the absence of a change in one item among a set of items. Methodology/Principal Findings:Twenty subjects performed two types of change detection tasks, the first task was detection of one changed item among a set of unchanged items (detection of the presence of a change) and the other was the detection of one unchanged item among a set of changed items (detection of the absence of a change). The ANOVA results for the percentage of correct responses and signal detection measurement of A’ values regarding change detection and the pattern of the results indicate that the subjects found (1) detection of the presence of change less difficult than detection of the absence of change (2), rejection of the presence of change less difficult than acceptance of the presence of change, and (3) rejection of the absence of change as difficult as acceptance of the absence of change. Conclusions/Significance:Retrieval/comparison processing for the detection of the presence of change differs from that for the absence of change, likely because the retrieval/comparison process appears aimed at determining whether an item has changed but not whether an item appears the same as it had previously. This conclusion suggests the existence of an identification process that recognizes each item as the same as that observed previously that exists apart from the mechanism underlying retrieval/comparison processing. [ABSTRACT FROM AUTHOR]

The article provides information on the testing method used by schools and educators to accurately assess the intelligence of children with physical disabilities, visual impairments and aphasic children in the U.S. The author mentioned nonverbal psychological or intelligence quotient (IQ) test, designed to evaluate cognitive ability without the need to assess language understanding and ability. The most common test used in nonverbal IQ is the Differential Abilities Scales while the more appropriate measure of nonverbal intelligence is the Comprehensive Test of Nonverbal Intelligence (CTONI). According to the author, these methods of standardized testing are ineffective in accurately assessing cognitive levels in children with physical and cognitive disabilities