University of Rochester

About: University of Rochester is a education organization based out in Rochester, New York, United States. It is known for research contribution in the topics: Population & Laser. The organization has 63915 authors who have published 112762 publications receiving 5484122 citations. The organization is also known as: Rochester University.

Deictic Codes for the Embodiment of Cognition

Abstract: To describe phenomena that occur at different time scales, computational models of the brain necessarily must incorporate different levels of abstraction. We argue that at time scales of approximately one-third of a second, orienting movements of the body play a crucial role in cognition and form a useful computational level, termed the embodiment level. At this level, the constraints of the body determine the nature of cognitive operations, since the natural sequentiality of body movements can be matched to the natural computational economies of sequential decision systems. The way this is done is through a system of implicit reference termed deictic, whereby pointing movements are used to bind objects in the world to cognitive programs. We show how deictic bindings enable the solution of natural tasks and argue that one of the central features of cognition, working memory, can be related to moment-by-moment dispositions of body features such as eye movements and hand movements.

Information Aggregation, Rationality, and the Condorcet Jury Theorem

Abstract: The Condorcet Jury Theorem states that majorities are more likely than any single individual to select the "better" of two alternatives when there exists uncertainty about which of the two alternatives is in fact preferred Most extant proofs of this theorem implicitly make the behavioral assumption that individuals vote "sincerely" in the collective decision making, a seemingly innocuous assumption, given that individuals are taken to possess a common preference for selecting the better alternative However, in the model analyzed here we find that sincere behavior by all individuals is not rational even when individuals have such a common preference In particular, sincere voting does not constitute a Nash equilibrium A satisfactory rational choice foundation for the claim that majorities invariably "do better" than individuals, therefore, has yet to be derived

The Hierarchical Model of Approach-Avoidance Motivation

Abstract: Approach motivation is the energization of behavior by, or the direction of behavior toward, positive stimuli (objects, events, possibilities), whereas avoidance motivation is the energization of behavior by, or the direction of behavior away from, negative stimuli (objects, events, possibilities). In this article, I provide a brief overview of this distinction between approach and avoidance motivation. In addition, I provide a brief overview of a model of motivation in which this approach-avoidance distinction plays an integral role—the hierarchical model of approach-avoidance motivation.

Service, value networks and learning

Abstract: Both supply chain management (SCM) and marketing in general have been moving from models and purposes narrowly focused on goods to more general models and purposes associated with partnerships, value networks, service provision, and value creation. Some of this movement has been captured in what has become known as service–dominant (S–D) logic. This article applies S–D logic to thinking about SCM in terms of service provision, in which goods are seen as service distribution or provisioning mechanisms, explores and elaborates on the concept of a value network, and develops a model of the firm as an essential service provisioning agent in a complex and adaptive value network. Research and managerial opportunities are also explored.

Relationship of serum sex steroid levels and bone turnover markers with bone mineral density in men and women: A key role for bioavailable estrogen

Abstract: Estrogen (E) deficiency associated with the menopause is the major cause of bone loss in aging women. However, men also lose significant amounts of bone with age, but they do not have the equivalent of menopause, and serum total testosterone (T) and E levels decline only marginally with age in men. Thus, it has been difficult to attribute bone loss in aging men to either T or E deficiency. Here, we show in a population-based, age-stratified sample of 346 men, aged 23-90 yr, that serum total T and E (estradiol plus estrone) levels decreased over the life span by 30% and 12%, respectively, but bioavailable (or nonsex hormone-binding globulin-bound) T and E levels decreased by 64% and 47%, respectively. In these men and in a parallel cohort of 304 women, aged 21-94 yr, serum PTH increased 84% and 64% over the life span, and urinary N-telopeptide of type I collagen (NTx) excretion, a bone resorption marker, increased 77% and 80% between age 50-85 yr in the men and women, respectively. By univariate analyses, serum bioavailable T and E levels correlated positively with bone mineral density (BMD) at the total body, spine, proximal femur, and distal radius and negatively with urinary NTx excretion in men and women. Urinary NTx excretion was also negatively associated with BMD in both sexes. By multivariate analyses, however, serum bioavailable E level was the consistent independent predictor of BMD in both men and postmenopausal women. Thus, bioavailable E levels decline significantly with age and are important predictors of BMD in men as well as women. These studies suggest that in contrast to traditional belief, age-related bone loss may be the result of E deficiency not just in postmenopausal women, but also in men.