Neurobehavioral factors associated with referral for learning problems in a community sample: evidence for an adaptational model for learning disorders

We evaluated community general education (CGE; n = 178), community special education (CSE; n = 30) and hospital-referred (HR, n = 145) children (ages 7-6 to 11-11) prospectively over a 2-year period. During this period, 17 CGE children were referred for evaluation (community referred; CR). Prior to referral, CR children performed more poorly than community-nonreferred (CNR) children on cognitive ability, academic achievement, attention problems, and information processing. CR group performance was equivalent to that of CSE and HR groups, but HR children showed poorer academic achievement. Referred children performed more poorly on all measures than nonreferred, whether they met formal diagnostic criteria for a learning disorder or not. Learning disorders may be better conceptualized as a context-dependent problem of functional adaptation than as a disability analogous to physical disabilities, raising questions about the validity of using psychometric test scores as the criterion for identification.     

Imbalanced expression of mitogen-activated protein kinase phosphatase-1 and phosphorylated extracellular signal-regulated kinases in lung squamous cell carcinoma

Objective  

Mitogen-activated protein kinases (MAPKs) are correlated with a more malignant phenotype in many cancers. This study was designed to evaluate the predictive value of the expression of MAPK phosphatase-1 (MKP-1) and phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK_1/2), as the key regulatory mechanism of the MAPKs, in lung squamous cell carcinoma (SCC).     

Science Letters： A TOM1 homologue is required for multiplication of Tobacco mosaic virus in Nicotiana benthamiana

The AtTOM1 gene ofArabidopsis thaliana had been shown to be essential for the efficient multiplication of Tobacco mosaic virus （TMV） in A. thaliana. In this study, we cloned an AtTOM1-like gene from Nicotiana benthamiana named as NbTOM1. Sequence alignment showed that NbTOM1 is closely related to AtTOM1 homologues of N. tabacum and Lycopersicon esculentum with 97.2% and 92.6% nucleotide sequence identities, respectively. Silencing of NbTOM1 by a modified viral satellite DNA-based vector resulted in complete inhibition of the multiplication of TMV in N. benthamiana. The result suggests that inhibition of NbTOM1 via RNA silencing is a potentially useful method for generating TMV-resistant plants.     

A prospective investigation of appraisals as mediators of the link between interparental conflict and child adjustment

This longitudinal study tested the role of children's appraisals of threat and self-blame as mediators of the association between interparental conflict and child adjustment in a sample of 298 Welsh children ages 11 to 12 years. Exposure to higher levels of interparental conflict at Time 1 predicted greater perceived threat and self-blame at Time 2, after accounting for the effects of Time 1 adjustment and appraisals on later appraisals. Perceived threat in turn was associated with increased internalizing problems at Tune 2, and self-blame was associated with higher externalizing problems. The pattern of results was largely consistent for child and parent reports of conflict and for boys and girls, though some gender differences were found in associations between appraisals and adjustment.     

Changes in inhibition during differential eyeblink conditioning with increased training

Three experiments examined inhibitory learning in rats, using Pavlovian and differential inhibitory eyeblink conditioning procedures. Experiment 1 was designed to compare summation and retardation effects following Pavlovian conditioned inhibition (A1/XA) or differential inhibition (A1/X) training using auditory and visual conditioned stimuli (CSs). After ten 100-trial sessions of training, both Pavlovian conditioned inhibition and differential inhibition produced a retardation effect. However, a summation effect was obtained only for rats given Pavlovian conditioned inhibition training. Experiment 2 showed that increasing differential inhibition training to twenty 100-trial sessions produced summation and retardation effects. In Experiment 3, rats were trained with either ten or twenty 100-trial sessions of intramodal inhibitory training with two tone CSs (2 kHz vs. 8 kHz). Summation and retardation effects were obtained after only 20 sessions of differential conditioning. The findings indicate that extensive training is needed to establish conditioned inhibition with intermodal or intramodal differential conditioning.     

Item difficulty in the evaluation of computer-based instruction: an example from neuroanatomy

This article reports large item effects in a study of computer-based learning of neuroanatomy. Outcome measures of the efficiency of learning, transfer of learning, and generalization of knowledge diverged by a wide margin across test items, with certain sets of items emerging as particularly difficult to master. In addition, the outcomes of comparisons between instructional methods changed with the difficulty of the items to be learned. More challenging items better differentiated between instructional methods. This set of results is important for two reasons. First, it suggests that instruction may be more efficient if sets of consistently difficult items are the targets of instructional methods particularly suited to them. Second, there is wide variation in the published literature regarding the outcomes of empirical evaluations of computer-based instruction. As a consequence, many questions arise as to the factors that may affect such evaluations. The present article demonstrates that the level of challenge in the material that is presented to learners is an important factor to consider in the evaluation of a computer-based instructional system.     

Child care research: an editorial perspective

The goals of Child Development's new From Another Perspective format are discussed, and an overview of the content of the inaugural From Another Perspective collection on child care effects is provided. The two lead articles suggest, respectively, that long hours in child care are related to children's later behavior problems and that child care may be physiologically challenging for young children. Commentaries focus on the need to examine a range of additional factors before drawing definitive conclusions about cause and effect. Among the issues discussed in the commentaries are the need to account for context, individual differences among children, and methodological challenges. The introductory editorial also overviews policy implications and directions for future research.