rwg: An assessment of within-group interrater agreement.

F. L. Schmidt and J. E. Hunter (1989) critiqued the within-group interrater reliability statistic (rwg) described by L. R. James et al (1984). S. W. Kozlowski and K. Hattrup (1992) responded to the Schmidt and Hunter critique and argued that rwg is a suitable index of interrater agreement. This article focuses on the interpretation of rwg as a measure of agreement among judges' ratings of a single target. A new derivation of rwg is given that underscores this interpretation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of ketotifen on human lymphocytes in vitro and in vivo

The effects of the antiasthmatic drug ketotifen (CAS 34580-13-7) on human mononuclear leukocytes were studied in vitro and in vivo. In vitro ketotifen concentration-dependently inhibited mitogen-stimulated lymphocyte proliferation. High ketotifen concentrations also inhibited T-lymphocyte mitogen- and adenosine triphosphate stimulated increases in intracellular Ca2+ in lymphocytes and the U937 human monocyte precursor cell line, respectively; this involved inhibition of both Ca2+ influx and intracellular mobilization. In in vivo experiments, treatment of healthy volunteers with 1 mg ketotifen b.i.d. for 7 d did not alter the number or subset composition of circulating lymphocytes. Moreover, the mitogen-stimulated in vitro proliferation of lymphocytes obtained before and after ketotifen treatment in vivo was similar. It is concluded that high ketotifen concentrations can inhibit the activation of resting lymphocytes in vitro but standard ketotifen treatment does not notably affect the number of function of circulating lymphocytes in vivo.     

Forced oscillations in an exothermic chemical reaction

We study non-linear behaviour in a model chemical reaction scheme (proposed by Sal?nikov), in which a single chemical species undergoes a two-stage, first-order decay process. The second stage is exothermic and has a temperature-dependent rate, and as a result, spontaneous oscillations in the temperature and the concentration of an intermediate chemical are known to be possible. An additional oscillation is imposed on the system by varying the ambient temperature in a sinusoidal manner. Primary resonance occurs when the forcing frequency coincides with the frequency of the natural oscillations in this scheme and an infinite sequence of super-and subharmonic resonances is also present. Chaos is possible for appropriate parameter values and may result either from the Feigenbaum period-doubling cascade, or else as a result of the Ruelle-Takens approach through quasi-periodicity.     

Brainstem auditory evoked responses in patients with tinnitus

Brainstem auditory evoked responses of 355 patients with uni- or bilateral tinnitus were recorded in order to evaluate the effect of tinnitus on the central auditory system. The amplitudes of waves I, III and V and the latencies of each wave and interpeak latencies were compared to those of a group of 129 controls with normal hearing. The study of the control group initially identified a certain number of concurrent parameters. The brainstem evoked responses of men and women evolved differently from the age of 30 years, latencies of I-III and I-V in men lengthening with age and those of women tending to shorten. The patient groups were therefore compared to a control group of the same sex ratio or of the same sex, half being between 30 and 56 years of age. The tinnitus patients were divided into three groups according to the side affected by tinnitus. Latencies and amplitudes in these groups differed significantly from those of the control group. In order to eliminate hearing loss, the most difficult concurrent factor and almost always associated with tinnitus, the results of individuals with symmetrical hearing loss were compared to those of the control group. Tinnitus was always associated with significant lengthening of 0-I and I-V latencies on the tinnitus-affected side, with a significant reduction in amplitudes of waves I and III, and sometimes of wave V, particularly in the group with left-sided tinnitus. Comparison of tinnitus patients with symmetrical and asymmetrical hearing by sex showed that tinnitus patients of all groups had lengthening of right and left 0-I latencies, apart from the women in the group with right-sided tinnitus, and significant reduction in amplitudes of waves I and III in women and of left III only in men. When hearing loss was asymmetrical and on the tinnitus-affected side, there was also lengthening of 0-I latencies on the tinnitus-affected side in both sexes and of ipsi- and contralateral I-V latencies in women. Right- and left-sided tinnitus was associated with additional differences between the three groups. Correlation coefficient study confirmed that 0-I, I- III and I-V latencies were independent of the mean degree of deafness, deafness at high frequencies and at frequencies around the tinnitus, up to a threshold of hearing loss of 40 dB, above which 0-I and 0-V lengthened in addition to tinnitus. On the other hand, whatever the frequency, tinnitus involved significant lengthening of wave I latencies and modification of the previously recorded amplitudes. Two groups of tinnitus patients could be distinguished: the first, with symmetrical hearing loss, with symmetrical normal latencies, apart from 0-I latencies and the amplitude of the wave on the tinnitus side, and the second with hearing loss predominant on the tinnitus-affected side, with different latencies on each side, 0-I being shorter on the unaffected side, I-III and I-V being lengthened on the unaffected side and 0-I being lengthened on the tinnitus-affected side. Moreover, as disturbances of brainstem evoked responses caused by tinnitus particularly affected waves I and III, the hypothesis of possible involvement of the efferent systems could be proposed.     

Determination of total non-sulphonated aromatic amines in soft drinks and hard candies by reduction and derivatization followed by high-performance liquid chromatography.

Utilizing elements of methodology developed previously for food colours, total free and bound non-sulphonated aromatic amines (NSAA) were determined in commercial samples of soft drink beverages and hard candies. Bound amines in the samples were reduced using sodium dithionite, then total NSAA were extracted into chlorofom, transferred to aqueous acid solution and diazotized with sodium nitrite before coupling with 2-naphthol-3,6-disulphonic acid, disodium salt (R-salt). The coloured derivatives were analysed using reversed-phase ion pair high-performance liquid chromatography (HPLC) and an absorbance detector set at 512 nm. Solid phase extraction cartridges were utilized for extraction and clean-up of the food colours present in the sample, and the concentration of each dye was determined quantitatively using HPLC and absorbance detector wavelengths of 426, 516 or 625 nm. Levels of total NSAA were compatible with those observed previously in food colours. Commercial soft drinks were found to contain (expressed in terms of total free plus bound NSAA in the beverage) 0.19-12.6 ng/ml of aniline, 0.83-8.25 ng/ml 1-naphthylamine and 0.62-1.12 ng/ml 2-naphthylamine. Levels of 0.66-9.15 ng/g of aniline and 2.48-10.6 ng/g 1-naphthylamine were found in commercial samples of hard candies. Bound NSAA in hard candies appeared to survive the manufacturing process. Recoveries averaged 96.9% for tartrazine and 89.6-97.2% for the bound amines when hard candies were prepared in the laboratory.     

Early childhood education for at-risk four-year-olds? Yes.

Extends E. F. Zigler's (see record 1987-23352-001) discussion of early childhood education, concluding, contrary to Zigler, that early childhood education for at-risk children is a positive step in helping them resist the harmful effects of poverty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Life stress and adjustment: Effects of life events experienced by young adolescents and their parents.

A longitudinal design was used to test the effects of life events experienced by young adolescents and their parents. The criteria were the adolescents' depression, anxiety, and self-esteem. The longitudinal analysis revealed a significant effect for the adolescents' controllable, but not uncontrollable, negative events. However, causal analyses revealed that this effect was the result of the significant relation between initial adjustment and the subsequent occurrence of controllable life stress (e.g., school suspension). The longitudinal analysis also revealed the stress-protective role of positive events, but only with respect to girls' self-esteem. There was no longitudinal support for the role of the parents' negative life events. These findings do not support the etiological importance of an accumulation of relatively discrete negative events experienced by early adolescents and their parents, but they do suggest the need (a) to conceptualize (controllable) life stress as a dependent variable in future research on developmental psychopathology; (b) to examine gender differences in early adolescent life stress; and (c) to develop more sophisticated measures of family life stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing the power of linkage detection by the transmission disequilibrium test and the identity-by-descent test

The purpose of this study was to identify new trends in the changing indications for penetrating keratoplasty. We retrospectively reviewed the clinical and pathologic diagnoses of 1,104 corneal buttons that had been submitted to the Estelle Doheny Eye Pathology Laboratory, Los Angeles, during the 5-year period 1989-1993. The leading indications, in order of decreasing frequency, were pseudophakic corneal edema (24.8%), regrafts (21.3%), scarring with or without chronic inflammation (11.1%), keratoconus (7.1%), aphakic corneal edema (6.4%), and ulcerative conditions (5.8%). The incidence of pseudophakic corneal edema remained stable over the study period and was actually surpassed by regraft in the last year of the study. Although pseudophakic corneal edema remains the predominant indication for penetrating keratoplasty, our findings suggest that its occurrence rate has begun to level off.