This paper considers the impact of random machine breakdowns on the classical Economic Production Quantity (EPQ) model for a product subject to exponential decay and under a no-resumption (NR) inventory control policy. A product is manufactured in batches on a machine that is subject to random breakdowns in order to meet a constant demand over an infinite planning horizon. The product is assume...

This article argues that a significant shift is taking place in the sociological study of religion, and seeks to outline its main features. In order to do so it returns to Stephen Warner’s classic article of 1993 which drew a contrast between ‘old’ and ‘new’ paradigms in the sociology of religion. It develops Warner’s analysis by setting these paradigms in their European and American contexts r...

The Chilean government commissioned a quasi-experimental study with a pre-/postintervention design that had two general aims: (a) to assess infants' psychoaffective developmental levels (pre-intervention phase) and (b) to evaluate whether an intervention based on the promotion of socioemotional development modifies the infant's psychoaffective development. Sixty-two institutionalized infants an...

Pollinator decline has been linked to landscape change, through both habitat fragmentation and the loss of habitat suitable for the pollinators to live within. One method for exploring why landscape change should affect pollinator populations is to combine individual-level behavioural ecological techniques with larger-scale landscape ecology. A modelling framework is described that uses spatial...

Although vocabulary tests are generally considered interchangeable, regardless of format, different tests can have different relations to age and to other cognitive abilities. In this study, 4 vocabulary test formats were examined: multiple-choice synonyms, multiple-choice antonyms, produce the definition, and picture identification. Results indicated that, although they form a single coherent ...

The number of adults aged 65 years and older is increasing rapidly, creating public health challenges. We used data from the 1995 and 2005 national surveys of Midlife in the United States (MIDUS) to compare changes in mental well-being of participants (n = 1007) of 3 age cohorts (ages 45-54 years, 55-64 years, and 65-74 years in 1995). Older adults experienced a slight decline in mental well-be...

Cryptic evolution has been defined as adaptive evolutionary change being masked by concurrent environmental change. Empirical studies of cryptic evolution have usually invoked a changing climate and/or increasing population density as the form of detrimental environmental change experienced by a population undergoing cryptic evolution. However, Fisher (1958) emphasized that evolutionary change ...

We develop a dynamic structural model to examine the e¤ects of di¤ering beliefs of the manager and outsider investors regarding the pro…tability of a …rm’s projects and managershareholder agency con‡icts on its capital structure. The manager receives dynamic incentives through explicit contracts with shareholders whose implementation through …nancial securities leads to a dynamic capital struct...

Earlier studies have revealed age-dependent differences in perception by dynamic touch. In the present study, we examined whether the capacity to learn deteriorates with aging. Adopting an ecological approach to learning, the authors examined the process of attunement--that is, the changes in what informational variable is exploited. Young and elderly adults were trained to perceive the lengths...