Automated sample-processing and titration system for determining uranium in nuclear materials

The system is designed for accurate, precise, and selective determination of from 10 to 180 mg of uranium in 2 to 12 cm/sup 3/ of solution. Samples, standards, and their solutions are handled on a weight basis. These weights, together with their appropriate identification numbers, are stored in computer memory and are used automatically in the assay calculations after each titration. The measurement technique (controlled-current coulometry) is based on the Davies-Gray and New Brunswick Laboratory method, in which U(VI) is reduced to U(IV) in strong H/sub 3/PO/sub 4/, followed by titration of the U(IV) with electrogenerated V(V). Solution pretreatment and titration are automatic. The analyzer is able to process 44 samples per loading of the sample changer, at a rate of 4 to 9 samples per hour. The system includes a comprehensive fault-monitoring system that detects analytical errors, guards against abnormal conditions which might cause errors, and prevents unsafe operation. A detailed description of the system, information on the reliability of the component subsystems, and a summary of its evaluation by the New Brunswick Laboratory are presented

Too Masculine, Too Bad Effects of Communion on Leaders’ Promotion of Cooperation

This study challenges researchers and practitioners in the field of leadership to consider communion as a relevant variable for (male) leadership effectiveness. We suggest that communal traits influence the ability of male leaders to engender cooperation and that this effect is stronger in male-dominated contexts. We argue that this is because relevant traits and leadership behaviors that underscore a sense of community are associated with stereotypically feminine roles and identity. In a series of three studies, experimental as well as survey-based, using Spanish, Dutch, and American samples, we examined such gendered construction of male leadership and its effects on cooperation. Among others, results are discussed in terms of how stereotypically masculine constructions of male leadership may create barriers to effective leadership

Reading Your Counterpart: The Benefit of Emotion Recognition Accuracy for Effectiveness in Negotiation

10.1007/s10919-007-0033-7Journal of Nonverbal Behavior314205-22

Enhancing preschoolers' executive functions through embedding cognitive activities in shared book reading

Given evidence that early executive functioning sets the stage for a broad range of subsequent outcomes, researchers have sought to identify ways to foster these cognitive capacities. An increasingly common approach involves computerized ‘brain training’ programs, yet there are questions about whether these are well suited for fostering the early development of executive functions (EFs). The current series of studies sought to design, develop, and provide evidence for the efficacy of embedding cognitive activities in a commonplace activity – shared reading of a children’s book. The book, Quincey Quokka’s Quest, required children to control their thinking and behaviour to help the story’s main character through a series of obstacles. The first study investigated effects of reading with embedded cognitive activities in individual and group contexts on young children’s executive functions (EFs). The second study compared reading with embedded cognitive activities against a more-active control condition (dialogic reading) that similarly engaged children in the reading process yet lacked clear engagement of EFs. The third study sought to investigate whether the effect of reading the story with embedded EF activities changed across differing doses of the intervention and whether effects persisted 2 months post-intervention. Findings provide converging evidence of intervention effects on working memory and shifting in as little as 3 weeks (compared to more traditional reading) and maintenance of these gains 2 months later. This suggests the efficacy of embedding cognitive activities in the context of everyday activities, thereby extending the range of users and contexts in which this approach can be used

Transient and sustained incentive effects on electrophysiological indices of cognitive control in younger and older adults

Preparing for upcoming events, separating task-relevant from task-irrelevant information and efficiently responding to stimuli all require cognitive control. The adaptive recruitment of cognitive control depends on activity in the dopaminergic reward system as well as the frontoparietal control network. In healthy aging, dopaminergic neuromodulation is reduced, resulting in altered incentive-based recruitment of control mechanisms. In the present study, younger adults (18–28 years) and healthy older adults (66–89 years) completed an incentivized flanker task that included gain, loss, and neutral trials. Event-related potentials (ERPs) were recorded at the time of incentive cue and target presentation. We examined the contingent negative variation (CNV), implicated in stimulus anticipation and response preparation, as well as the P3, which is involved in the evaluation of visual stimuli. Both younger and older adults showed transient incentive-based modulation of CNV. Critically, cue-locked and target-locked P3s were influenced by transient and sustained effects of incentives in younger adults, while such modulation was limited to a sustained effect of gain incentives on cue-P3 in older adults. Overall, these findings are in line with an age-related reduction in the flexible recruitment of preparatory and target-related cognitive control processes in the presence of motivational incentives

Beyond quantitative and qualitative traits: three telling cases in the life sciences

This paper challenges the common assumption that some phenotypic traits are quantitative while others are qualitative. The distinction between these two kinds of traits is widely influential in biological and biomedical research as well as in scientific education and communication. This is probably due to both historical and epistemological reasons. However, the quantitative/qualitative distinction involves a variety of simplifications on the genetic causes of phenotypic variability and on the development of complex traits. Here, I examine three cases from the life sciences that show inconsistencies in the distinction: Mendelian traits (dwarfism and pigmentation in plant and animal models), Mendelian diseases (phenylketonuria), and polygenic mental disorders (schizophrenia). I show that these traits can be framed both quantitatively and qualitatively depending, for instance, on the methods through which they are investigated and on specific epistemic purposes (e.g., clinical diagnosis versus causal explanation). This suggests that the received view of quantitative and qualitative traits has a limited heuristic power—limited to some local contexts or to the specific methodologies adopted. Throughout the paper, I provide directions for framing phenotypes beyond the quantitative/qualitative distinction. I conclude by pointing at the necessity of developing a principled characterisation of what phenotypic traits, in general, are