Countermeasures for night work performance deficits: The effect of napping or caffeine on continuous performance at night

Napping and caffeine consumption, two common strategies for improving alertness and performance on the night shift, were investigated in two separate studies. Performance was measured with a simulated assembly line task (SALT) during a single night work shift. Both strategies proved beneficial. Performance and subjective alertness were improved following either a 2.3-h evening nap or ingestion of caffeine (4 mg/kg) prior to the work shift. The effects were noted particularly at the trough of circadian alertness. Although neither napping nor caffeine countered the strong circadian influence on performance and alertness in the early morning hours, both strategies attenuated their sharp decline. Further research is required to determine the generalizability of these findings beyond a single night shift and in different populations of workers, such as older age groups, or chronic caffeine users.     

Akinetic model of population dynamics

The relations between fertility, mortality, growth rate and age distribution in closed populations have been derived by means of a set of differential equations based on the well known theory of chemical kinetics. The classical relations for stable populations are easily obtained in this model by simple algebraic manipulations. A rough but useful further simplification is to divide the population into three groups—pre-reproductive, reproductive, and post-reproductive. For this three-group model simple algebraic expressions connect fertility, mortality, growth rate and the fractions of the population in each group. Although the relations obtained are not precise, they serve to illustrate simply and directly the interactions among the basic population variables.     

Finding a routine that works: A mixed methods study of foster parents

Although it is well established that daily routines are important for family well‐being, very little research has been done on how foster parents establish and integrate new foster children into family routines. We used a mixed‐methods, cross‐sectional design, focused on qualitative results to explore how foster parents utilize routines. Twenty‐three foster parents were recruited from a private child welfare agency in a large city in the United States. Surveys were administered to obtain demographic information, overall home atmosphere, and the importance and prevalence of different routines, including mealtimes and sleep schedules. Nine foster parents received a semistructured interview with open‐ended questions. Foster parents reported that routines such as bedtimes, mealtimes, chores, and homework were essential to family well‐being. Because both parents and children had to adjust to living together in an intimate family environment, it was important to establish routines quickly. Foster parents modified routines depending on their child's needs. Along with typical family routines, foster parents reported additional tasks, such as visits with biological parents, meetings with caseworkers, and trainings that affected their family schedule. Results imply that training foster care workers and foster parents about routines can engender stability and emotional belonging for children.     

Stretching the Truth: Elastic Justification and Motivated Communication of Uncertain Information

Although both cognitive and motivational factors can influence the communication of uncertain information, most of the work investigating the communication of uncertainty has focused on cognitive factors. In this article, we demonstrate that motivational factors influence the communication of private, uncertain information and we describe the relationship between elasticity (i.e. uncertainty and vagueness) and motivated communication. We report results from four experiments that demonstrate that motivated communication is not purely opportunistic. The values people report are constrained by the elasticity of private information even when the costs and benefits of misrepresenting information are held constant. Perceptions of justifiability mediate the relationship between elasticity and motivated communication, and we explain our results in terms of the self-justification process.