Peer-tutoring: Applied behavior analysis working in the classroom.

Schools often use peer-tutoring as a corrective program for students who are experiencing difficulties academically. Given appropriate behavioral structure, peer-tutoring can become a powerful classwide instructional intervention. An historical perspective on the use of students as teachers for their peers is given in this selective literature review. Also, information on the efficacy of considering behavioral function and structure and data addressing ecobehavioral variables to establish a productive learning environment are provided. The authors emphasize infusing peer-tutoring programs with applied behavior analysis techniques to increase the academic success of large numbers of students cost effectively. Peer-tutoring programs are considered to be a way for applied behavior analysts to gain greater access to American school learning environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prenatal diagnostic testing for familial dysautonomia using linked genetic markers

Familial dysautonomia (FD), a recessively inherited disease, has been mapped to chromosome 9q31. Highly polymorphic dinucleotide repeat markers flanking the genetic locus and at the same genetic location have been identified. We describe the prenatal diagnosis of FD using linkage and linkage disequilibrium analyses with these markers. Twelve families were analysed for informativeness and of these, seven went on to have prenatal testing (a total of eight fetuses tested). All of these fetuses were predicted to be heterozygous unaffected (FD carriers). Seven fetuses have come to term and are normal. In the absence of a recombinant proband, a panel of three proximal and three distal markers is sufficient to provide informative flanking markers and an 87-96 per cent likelihood of a highly predictive test. In an additional family at 1:4 risk for FD, no DNA was available from the propositus. This family was analysed using linkage disequilibrium to the #18 allele of the tightly linked marker D9S58 in conjunction with linkage analysis using data from two unaffected children. Prenatal diagnosis in this family indicated an affected fetus.     

Cannabidiol and (-)Delta9-tetrahydrocannabinol are neuroprotective antioxidants

The neuroprotective actions of cannabidiol and other cannabinoids were examined in rat cortical neuron cultures exposed to toxic levels of the excitatory neurotransmitter glutamate. Glutamate toxicity was reduced by both cannabidiol, a nonpsychoactive constituent of marijuana, and the psychotropic cannabinoid (-)Delta9-tetrahydrocannabinol (THC). Cannabinoids protected equally well against neurotoxicity mediated by N-methyl-D-aspartate receptors, 2-amino-3-(4-butyl-3-hydroxyisoxazol-5-yl)propionic acid receptors, or kainate receptors. N-methyl-D-aspartate receptor-induced toxicity has been shown to be calcium dependent; this study demonstrates that 2-amino-3-(4-butyl-3-hydroxyisoxazol-5-yl)propionic acid/kainate receptor-type neurotoxicity is also calcium-dependent, partly mediated by voltage sensitive calcium channels. The neuroprotection observed with cannabidiol and THC was unaffected by cannabinoid receptor antagonist, indicating it to be cannabinoid receptor independent. Previous studies have shown that glutamate toxicity may be prevented by antioxidants. Cannabidiol, THC and several synthetic cannabinoids all were demonstrated to be antioxidants by cyclic voltametry. Cannabidiol and THC also were shown to prevent hydroperoxide-induced oxidative damage as well as or better than other antioxidants in a chemical (Fenton reaction) system and neuronal cultures. Cannabidiol was more protective against glutamate neurotoxicity than either ascorbate or alpha-tocopherol, indicating it to be a potent antioxidant. These data also suggest that the naturally occurring, nonpsychotropic cannabinoid, cannabidiol, may be a potentially useful therapeutic agent for the treatment of oxidative neurological disorders such as cerebral ischemia.     

Topographic profiling and refractive-index analysis by use of differential interference contrast with bright-field intensity and atomic force imaging

A methodology is described for phase restoration of an object function from differential interference contrast (DIC) images. The methodology involves collecting a set of DIC images in the same plane with different bias retardation between the two illuminating light components produced by a Wollaston prism. These images, together with one conventional bright-field image, allows for reduction of the phase deconvolution restoration problem from a highly complex nonlinear mathematical formulation to a set of linear equations that can be applied to resolve the phase for images with a relatively large number of pixels. Additionally, under certain conditions, an on-line atomic force imaging system that does not interfere with the standard DIC illumination modes resolves uncertainties in large topographical variations that generally lead to a basic problem in DIC imaging, i.e., phase unwrapping. Furthermore, the availability of confocal detection allows for a three-dimensional reconstruction with high accuracy of the refractive-index measurement of the object that is to be imaged. This has been applied to reconstruction of the refractive index of an arrayed waveguide in a region in which a defect in the sample is present. The results of this paper highlight the synergism of far-field microscopies integrated with scanned probe microscopies and restoration algorithms for phase reconstruction.     

Confirmatory factor analysis of the WAIS–III standardization data.

Confirmatory factor analyses with the standardization data of the Wechsler Adult Intelligence Scale–Third Edition (Wechsler, 1997a) compared 6 models with 1 to 4 factors for 11- and 13-subtest versions of the test. Three factors usually fit the data better than 2 factors, but 2-factor models were more parsimonious. A 2-factor model with a Verbal Comprehension factor (Vocabulary, Similarities, Information, and Comprehension) was as good as and sometimes better than the 2-factor model defined by the traditional separation of Verbal and Performance subtests. For 3-factor models, alternative specifications of processing speed subtests on either the Perceptual Organization or Freedom From Distractibility factor were comparable, and specifying a 4th factor for Digit Symbol and Symbol Search had little advantage in comparison with 3-factor models with correlated errors for the 2 subtests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An approximate analysis of a starting process of a current sourceparallel inverter with a high-Q induction heating load

An approximate analysis of the start-up process of a resonant loaded current source parallel inverter is presented. The proposed approach may be applied to inverters whose industrial applications are induction heating and metal melting installations. To estimate the eigenvalues of the third-order set of differential equations, the iteration method has been used. By using the arrived at formulas it is possible to select inverter thyristors that meet the inverter start-up characteristics. The approximate formula's accuracy was estimated by computer-aided analysis. It is shown that at the inverter starting process the turn-off angle changing may be of two kinds: monotonous or oscillating. Regions of inverter parameters that cause one or the other of these two processes are determined. When the changing of the turn-off angle is monotonous, the achieved approximate formulas can be used. The analysis of the oscillating process was performed by applying the experimental design theory statistical methods to the computer-simulation results and the approximate formulas for the oscillating region were also obtained. Two examples of the inverter design procedure and thyristor choosing techniques are given. Finally, an experimental verification of the calculation results is performed     

Changing patterns of cutaneous leishmaniasis in Israel and neighbouring territories

The most frequent form of cutaneous leishmaniasis (CL) in Israel and the neighbouring territories is due to Leishmania major, which is endemic mainly in the Jordan Valley and in the Rift Valley. CL due to L. tropica is much less common, and in the past only sporadic cases have been reported. In this study we present data obtained during the years 1988-1992 regarding CL in the area. Our clinic has diagnosed a total of 371 leishmaniasis cases, most of whom acquired the infection in the Jordan Valley, mainly during June and July. About one-third of the patients had single lesions, and one-third more than 5 lesions. We also describe an outbreak of leishmaniasis in Kfar Adumim, a village 15 km east of Jerusalem, where leishmaniasis was previously unknown. Parasites were characterized by the polymerase chain reaction and by immunostaining, and found to be both L. tropica and L. major. The localization of the homes of the affected people on a slope where hyraxes were abundant suggests that these animals might have been involved in the transmission of L. tropica in this area.     

Indicine-N-oxide: the antitumor principle of Heliotropium indicum

Extracts of Heliotropium indicum Linn. (Boraginaceae) showed significant activity in several experimental tumor systems. The active principle is isolated and shown to be the N-oxide of the alkaloid, indicine, previously isolated from this plant. Supporting structural data and anti-tumor data are provided.     

Memory: When less is more.

Loss of memory for the characteristics of stimuli (i.e., forgetting of stimulus attributes) can lead to increases in behavior, a consequence quite different from the impairments associated with the forgetting of responses. Evidence from animal and human research for the forgetting of stimuli as a distinct memory principle is presented, and the methodological and conceptual implications of this pervasive type of memory loss are considered. Malleability of eyewitness memory, cognitive confusions, sleeper and familiarity effects, and temporal distortions in inferences and attributions are among the varied behavioral phenomena that can be accounted for in terms of forgetting of stimulus attributes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-validation of predicted Wechsler Memory Scale—Revised scores.

Equations for prorating the Wechsler Memory Scale—Revised General Memory (GM) and Delayed Recall (DR) index scores (J. L. Woodard & B. N. Axelrod,1995) were confirmed in a new clinical sample of 258 patients. Raw score results for Logical Memory, Visual Reproduction, and Verbal Paired Associates were entered into the prediction equations. Predicted GM and DR scores fell within 6 points of obtained scores for 94% and 97% of the sample, respectively. A multiple regression analysis yielded multiple R–2 of .976 and .984 for GM and DR, respectively. In addition, the unstandardized regression weights were virtually identical to those initially presented by Woodard and Axelrod. These prediction equations for the GM and DR summary scores have validity for patient samples similar to those of the present study. (PsycINFO Database Record (c) 2011 APA, all rights reserved)