Hemispheric specialization for speech in language-disordered children

The present experiment addressed the hypothesis that children with language disorders may have atypical patterns of hemispheric asymmetry of function. Ten children with various language disorders and 10 normal controls were given a 480 trial consonant-vowel dichotic listening test to obtain a measure of speech laterization. The data were analyzed in terms of performance as a function of whether the two dichotic inputs shared a phonetic feature (voice or place), in addition to percent correct for each ear. Group analysis of the data revealed no significant differences between the experimental children and the controls with respect to the magnitude of the right ear advantage or the effect of shared phonetic features, although the experimental children reported significantly fewer syllables overall. An analysis of the performance of individual children, however, showed that the size of the ear asymmetry was inversely related to severity of linguistic impairment.     

Motor effects of cholinergic stimulation of the globus pallidus in rats.

Forty-seven rats were cannulated permanently in either the globus pallidus or neostriatum and subsequently injected with carbachol, scopolamine, or carbachol plus scopolamine. The injection of carbachol (1 mug) into the globus pallidus produced transient hyperkinetic phasic dyskinesias (84%) followed in some cases by ipsilateral circling (47%) associated with hypertonic contralateral hind limbs. This condition progressed in some rats to a cataleptic state (42%). The injection of scopolamine (50 mug) or scopolamine (50mug) plus carbachol (1 mug) into the pallidum produced ipsilateral circling associated with hypotonia of the contralateral hind limb in a few rats. No hyperkinetic dyskinesias nor catalepsy were produced by these injections. The injection of carbachol (1 mug) into the neostriatum produced hyperkinetic dyskinesias (86%) of long duration, minimal circling (both directions) (10%), and catalepsy (29%). These effects were blocked by the addition of 50 mug of scopolamine to the carbachol injection. Scopolamine (50-100 mug) alone produced no effects after injection into the caudate/putamen. Saline injections in the neostriatum or globus pallidus produced no motor disturbance.     

Estimating Intervention Effectiveness: Synthetic Projection of Field Evaluation Results

In a 46-site, 5-year high-risk youth substance abuse prevention evaluation, effect sizes were adjusted using a meta-analytic regression technique to project potential effectiveness under more optimal research and implementation conditions. Adjusting effect size estimates to control for the impact of comparison group prevention exposure, service intensity, and coherent program implementation raised the mean effectiveness estimate from near zero (.02, SD = .21) to .24 (SD = .18). This finding suggests that adolescent prevention programs can have significant positive effects under optimal, yet obtainable conditions.Editors’ Strategic Implications: The authors present a meta-analytic technique that promises to be an important tool for understanding what works in multi-site community-based prevention settings. Researchers will find this to be a creative approach to model the “noise’’ in implementation that may often overshadow the potential impact of prevention programs.     

Ageisms

In this paper some very fundamental attitudes we have and assumptions we make in the US about persons, what they owe and what they are owed, are scrutinized and found to be indefensibly ageist. It is argued that these assumptions and the attitudes they engender are supported by logically and ethically suspect methods and conclusions. These errors are summarized and some remedial steps by which we might better protect against such illicit and unwarranted methods and conclusions in the future are suggested.     

Use and Abuse of Bioethics: Integrity and Professional Standing

This paper sets out to examine the integrity and professional standing of Bioethics. It argues that professions have certain responsibilities that start with setting criteria for and credentialing those that have met the criteria and goes on to ultimately have social responsibilities to the community. As it now stands we claim that Bioethics—while it certainly has achieved some progress in the way medicine has developed—has failed to become a profession and has to a large extent failed in its social responsibility. We feel that Bioethics has to define itself, set criteria for membership in the profession, police itself and—above all—meet its social responsibility to become a profession meriting that name.     

Detection of Mature Collagen in Human Dental Enamel

Mature dental enamel is the most mineralized of all mammalian tissues and considered to be free of collagen. Hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) are two nonreducible cross-links of mature collagen. Hydroxyproline (Hyp) is an amino acid that is believed to be indicative of the presence of collagen. We set out to assess the concentrations of Hyp, HP, and LP in dental enamel and dentin (control) to clarify whether there was minor collagen content in dental enamel. We studied 17.53 g of enamel and 22.12 g of dentin gained from 120 extracted human teeth. Enamel and dentin (control) were separated with a diamond dental drill under microscopic control by wasting a margin of enamel (Ca. 2 mm) at the dentin-enamel border. Collagen alpha-chains were analyzed by Sodium dodecylsulfate-polyacrylamide gel (SDS-PAGE) after decalcification and collagen extraction. Concentrations of HP and LP where measured by using high-performance liquid chromatography (HPLC). Hyp was analyzed by a spectrophotometric method. The pooled probe of enamel contained 0.23 mug/g of Hyp. This concentration was 49 times lower than that in dentin. Concentrations of HP and LP in enamel were 0.07 nmol/g and 0.02 nmol/g, respectively being 605.57 (HP) and 251.50 (LP) times lower in enamel as compared to dentin. Collagen type I was found in enamel; collagen types I and V were found in dentin samples. In reports of many studies and textbooks, collagen is considered to be completely absorbed in the course of the mineralization and maturation of dental enamel. We show that this is not the case. However, the concentration of collagen in enamel was considerably lower as compared to that in dentin.     

Gelpermeationschromatographie. 1. Mitt. Die trennung oligomerer modellsubstanzen aus diphenylcarbonat und 4.4′-dihydroxy-diphenyl-2.2′-propan (bisphenol A)

Separation of mixtures of model oligomers of diphenylcarbonate and 4.4′-dihydroxy-diphenyl-2.2′-propane (bisphenol A) have been attempted by gelpermeation chromatography with Sephadex gels (LH-20). Measurements of distribution coefficients(K_d-values) show that for substances with phenol endgroups, the coefficients are higher than that expected from their molecular weight, the reason for which may be adsorption effect on the column material. Bisphenol A has a particularly high distribution coefficient. Its separation from other substances is theoretically and experimentally investigated. Thus a new method for quantitative determination of bisphenol A is found.