A note on 3-state systems

D.M. Malon (ibid., vol. 38, p.275-6, Aug. 1989) points out a pitfall of certain reliability problems pertaining to systems of three-state devices. The inference to be drawn from his observation is that special care should be used in describing such systems and in specifying exactly what constitutes success and failure. The present authors (ibid., vol.37, p.388-94, Oct. 1988) have modeled systems that can be represented by a network with designated source and sink; the reliability problem they treated is described by the following two system failures: (1) the system fails (short) if there is a path of short-failed components joining the source and the sink; (2) the system fails (open) if every path joining the source and sink includes an open-failed component. The systems they modeled are therefore somewhat more general then the array structures treated by B.W. Jenney and D.J. Sherwin (ibid., vol.R-35, p.532-8, Dec. 1986). But since the two failure-modes are mutually exclusive, the pitfall that Malon describes does not affect the former. Jenney and Sherwin's difficulties do not arise because of the generality of the systems; rather, they appear in some of the more general reliability measures (such as j-out-of-m requirements) used on the sp-arrays and ps-arrays     

Primary- and secondary-control strategies in later life: Predicting hospital outcomes in men and women.

Community-dwelling individuals (n = 143, 73-98 years old) were assessed to consider if their use of task-specific control strategies predicted hospital outcomes in the subsequent 2 years. The authors were interested in whether men and women facing health-induced task restrictions benefited equally from the use of primary- and secondary-control strategies. Gender interacted with primary-control strategies; men's more frequent use of these proactive strategies generally related to fewer hospital admissions. Gender also interacted with secondary-control strategies; women's more frequent use of compensatory (self-protective) strategies corresponded to fewer hospital admissions and shorter hospital stay durations. Taken together, our findings suggest that men benefit by adopting certain primary-control strategies and women benefit by adopting certain compensatory secondary-control strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Investigation of the construct validity of a self-report measure of goal commitment.

The purpose of this research was to develop an efficient, construct-valid measure of goal commitment. Drawing from a set of 9 unidimensional items, a 4-item unidimensional scale was developed that exhibited a .71 internal consistency estimate of reliability. This scale showed statistically significant relationships with 3 alternative measures of the same construct: force to attain the goal, self-set goal–assigned-goal discrepancy, and actual goal change. With respect to other constructs in the goal commitment nomological net, the results indicated that the scale was consistently related to performance. Moreover, the pattern of the results with expected antecedents such as goal publicness, monetary incentives, need for achievement, locus of control, and task involvement were statistically significant and in the predicted direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Microtox Toxicity Test Results for Water Samples from the Detroit River

The toxicities of over 70 water samples from the Detroit River between Lake St. Clair and the western basin of Lake Erie to the bioluminescent Photobacterium phosphoreum were determined with the Microtox toxicity analyzer. The samples were analyzed in the field within a few hours of collection and again several weeks later in the laboratory. After the storage, the samples were fractionated by distillation under vacuum. This process yielded three fractions of each sample of which the first fraction, enriched in some of the volatile contaminants, and the third fraction, containing the non-volatile compounds, were analyzed. High toxicities were found for several of the original samples and also for the first and third fractions of some concentrated samples. Testing of samples with this system provided a general overview of acute toxicity and may be useful for the quick recognition of contamination hotspots.     

An archival prospective study of mental health and longevity.

The relationship between mental health status and longevity was examined in an archival prospective cohort study (N?=?1,103) derived from work begun by Lewis Terman in the 1920s. Degree of psychological maladjustment, cumulatively rated by Terman and his colleagues as of 1950, was found to be related to higher risk of all-cause mortality over a 4-decade follow-up period. The differences among causes of death were nonsignificant, but there was some indication that mental health problems were more strongly related to deaths from injury and cardiovascular disease. The overall relationship was significant for men but weaker for women. The effect was not substantially mediated by alcohol consumption, obesity, or cigarette smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance posting, goal setting, and activity-contingent praise as applied to a university hockey team.

Rate of legal body checking (hit rate) was targeted for change for each of two consecutive seasons for a university hockey team that had a chronic losing record. Following baseline recording (A), the interventions of publicly posted individual feedback (B), goal setting (C), and praise (D) were successively introduced "on-the-baseline" using a components-analysis research strategy. An analogous design and procedure was used the following season, with the exception that more intensive training was given to the coach on the delivery of praise. Overall, the mean hit rate increased 82% (excluding the highly talented senior players who initiated the first project application) and 141% (no exclusions), respectively, for the 2 years. Moreover, with the single exception of the praise treatment of the first year, increments in hit rate occurred with the onset and tenure of each intervention (most ps?     

Oxidation of sulfur components in diesel fuel using Fe-TAML catalysts and hydrogen peroxide

Dibenzothiophene-derivatives are catalytically oxidized to their corresponding sulfone product in homogeneous and two-liquid phase systems by H₂O₂ with an iron containing tetraamidomacrocyclic ligand (TAML) catalyst, Fe-TAML^®. The reaction medium is slightly caustic, pH 8, and uses t-BuOH as a co-solvent for solubilizing the dibenzothiophene starting compounds and their oxidation products. Fe-TAML^® catalyst concentrations are in the low micromolar range. H₂O₂ consumption is nearly stoichiometric (two-equivalents) in homogeneous conditions and only slightly less efficient under two-liquid phase conditions. The catalytic process when applied to a sample of commercial diesel fuel occurs under mild conditions with respect to temperature (50 °C), pressure (1 atm), and time (3 h), to remove greater than 75% of the total sulfur content of the fuel after secondary treatment with silica. Both alkyl-benzothiophenes and alkyl-dibenzothiophenes compounds in the diesel fuel were oxidized by the Fe-TAML^®/H₂O₂ system which facilitated their adsorption onto the silica. The mild reaction conditions result in no detectable over-oxidation of alkyl-dibenzothiophenes.     

Perceptual units in the acquisition of visual categories.

A series of experiments provided evidence that the representational structure of categories comprising dot patterns is based on pattern parts and pattern configuration rather than on pattern elements. Similarity judgments and postacquisition classification data could not be explained in terms of element-level perceptual units, even for categories of dot patterns with 7 of their 8 dots in the exact same relative location. The importance of higher order perceptual units was indicated by evidence that long-term retention of information specific to previously learned category exemplars, which is typical of natural objects, can also be obtained for artificial dot patterns, providing their structure reflects perceptual characteristics identified in Tversky and Hemenway's (1984) study of natural objects: Members of the same category had to be perceptually distinctive at the pattern configuration level and perceptually similar at the level of pattern parts. The level of within-category similarity for a set of categories (relative to between-categories similarity) did not predict whether item-specific information would be retained; long-term retention appears to require both within-category similarity and dissimilarity, but at different levels of perceptual structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Friends' and classmates' interactions on academic tasks.

As they worked on two academic tasks, pairs of friends and pairs of other classmates were observed to determine the effects of existing social relationships on interactions during cooperative learning. A total of 130 third graders and seventh graders were paired either with a close friend or with another classmate who was not a close friend. Each pair of students was videotaped, first, as they discussed topics from social studies texts and, second, as they took turns asking each other questions about the topics. Measures of the content of the students' conversations and of interactional processes (e.g., agreements and disagreements) showed no significant differences between friends' and other classmates' interactions. On a posttask questionnaire, however, the pairs of friends said that they engaged in more academic and nonacademic activities outside the experimental setting than did the pairs of other classmates. The implications of the results for the assignment of students to cooperative learning groups are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)