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Biomedical subjects

L Mann

Publications and source records attributed to L Mann.

At least 55 records · Page 3Linked to original sources

A micromethod for the analysis of zinc in plasma or serum by atomic absorption spectrophotometry using graphite furnace.

A micromethod is described for the analysis of zinc in plasma or serum by electrothermal atomisation and graphite furnace utilising less than 20 microliters sample volume. The sample matrix introduced an error when aqueous standards were used. Therefore standards were made up in serum which had been treated with Chelex 100 to remove as much zinc as possible. The residual zinc (less than 0.125 mg/l) was determined by flame analysis using the method of additions and each standard assigned a value equal to the sum of the residual zinc and the amount added. Furnace analyses using standards made up in Chelex-treated serum compared favourably with flame analyses over the whole range, and recovery experiments gave 98 +/- 2% of the expected value with 95 +/- 6% recovery of the added zinc. The within-batch coefficient of variation was 2.5%, day-to-day variation 5.6%. The mean concentration of zinc in paired samples of plasma and serum from 50 adults analysed by flame with viscosity-matched aqueous standards were: plasma (mean +/- SD) 0.821 +/- 0.085 mg/l; serum 0.821 +/- 0.07 mg/l. The same samples were analysed in the graphite furnace using serum standards, and the results were: plasma 0.812 +/- 0.082 mg/l; serum 0.815 +/- 0.08 mg/l. In contrast to earlier reports we were unable to demonstrate a significant difference between plasma and serum zinc concentration in the paired samples.

Adult↗

The baiting crowd in episodes of threatened suicide.

This study examines 21 cases in which crowds were present when a disturbed person threatened to jump off a building, bridge, or tower. Baiting or jeering occurred in 10 of the cases. Analysis of newspaper accounts of the episodes suggests several deindividuation factors that might contribute to the baiting phenomenon: membership in a large crowd, the cover of nighttime, and physical distance between crowd and victim (all factors associated with anonymity). The baiting phenomenon was also associated with warm temperatures and long duration of episode. These factors suggest leads for more systematic investigation.

Humans↗

Emergency decision making: a theoretical analysis of responses to disaster warnings.

This article presents a theoretical model of emergency decision making that focuses on the decision maker's answers to basic questions evoked by warnings or signs of danger. Effective emergency decisions are most likely to be made, according to the theory, when a vigilant coping pattern is dominant, which requires that the following four mediating conditions are met: 1) awareness of serious risks if no protective action is taken; 2) awareness of serious risks if any of the salient protective actions is taken; 3) moderate or high degree of hope that a search for information and advice will lead to a better (i.e., less risky) solution; and 4) belief that there is sufficient time to search and deliberate before any serious threat will materialize. When one or another of these conditions is not met, a defective coping pattern, such as defensive avoidance or hypervigilance, will be dominant, which generally leads to maladaptive actions. In addition to suggesting new interventions for facilitating adaptive behavior in emergencies, the theoretical model provides a basis for integrating disparate findings from psychological research on the effects of warnings and confrontations with danger.

Adaptation, Psychological↗

Discriminators of clinically defined emotional maladjustment. Predictive validity of the Behavior Problem Checklist and Devereux scales.

From a population of 130 boys between 7 and 14 years of age who had been clinically diagnosed as aggressive, hyperactive, or withdrawn, 32, 31, and 32 Ss, respectively, were randomly selected. All Ss were rated on the Behavior Problem Checklist (BPC) and the Devereux Elementary School Behavior rating scales (DESB) during the 1971-72 academic year. A descriptive intercorrelation matrix was generated for the 4 BPC scales and the 14 DESB scales. Three stepwise discriminant analyses were run: (a) BPC scales only, (b) DESB scales only, and (c) BPC and DESB scales combined. In terms of statistical and practical considerations, the four BPC subscales by themselves attained the optimal predictive accuracy (65%, or 62 of 95 children correctly identified).

Adolescent↗