Brown University

About: Brown University is a education organization based out in Providence, Rhode Island, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 35778 authors who have published 90896 publications receiving 4471489 citations. The organization is also known as: brown.edu & Brown.

Delayed reward discounting and addictive behavior: a meta-analysis

Abstract: Rationale Delayed reward discounting (DRD) is a behavioral economic index of impulsivity and numerous studies have examined DRD in relation to addictive behavior. To synthesize the findings across the literature, the current review is a meta-analysis of studies comparing DRD between criterion groups exhibiting addictive behavior and control groups.

A threatening intellectual environment: why females are susceptible to experiencing problem-solving deficits in the presence of males.

Abstract: Does placing females in environments in which they have contact with males cause deficits in their problem-solving perfor- mance? Is a situational cue, such as gender composition, sufficient for creating a threatening intellectual environment for females—an en- vironment that elicits performance-impinging stereotypes? Two stud- ies explored these questions. Participants completed a difficult math or verbal test in 3-person groups, each of which included 2 additional people of the same sex as the participant (same-sex condition) or of the opposite sex (minority condition). Female participants in the mi- nority condition experienced performance deficits in the math test only, whereas males performed equally well on the math test in the two conditions. Further investigation showed that females' deficits were proportional to the number of males in their group. Even females who were placed in a mixed-sex majority condition (2 females and 1 male) experienced moderate but significant deficits. Findings are dis- cussed in relation to theories of distinctiveness, stereotype threat, and tokenism. Females currently are a small minority of students and researchers in the natural and physical sciences. A recent National Science Foun- dation (1996) report showed that females constitute 35% of under- graduate students enrolled in physics, math, and computer science classes; 16% of undergraduate students enrolled in engineering classes; and less than 10% of graduate students in physics and engi- neering. Moreover, this report showed that females suffer from higher attrition rates in their academic careers than do males, so that by the time women reach the workplace, they occupy only 22% of jobs in mathematical and scientific domains. Does females' problem-solving performance diminish when they are placed in an environment in which males outnumber them? If so, are such performance deficits specifically linked to domains that are associated with negative ste- reotypes about females' intellectual capacity? Examining these ques- tions can inform theories of how social stereotypes affect the intellectual processing of individuals who are the targets of these stereotypes, as well as educational practice.

Smart Cities: Quality of Life, Productivity, and the Growth Effects of Human Capital

Abstract: From 1940 to 1990, a 10 percent increase in a metropolitan area's concentration of college-educated residents was associated with a .8 percent increase in subsequent employment growth. Instrumental variables estimates support a causal relationship between college graduates and employment growth, but show no evidence of an effect of high school graduates. Using data on growth in wages, rents and house values, I calibrate a neoclassical city growth model and find that roughly 60 percent of the employment growth effect of college graduates is due to enhanced productivity growth, the rest being caused by growth in the quality of life. This finding contrasts with the common argument that human capital generates employment growth in urban areas solely through changes in productivity.

The Fusiform Face Area is Part of a Network that Processes Faces at the Individual Level

Abstract: According to modular models of cortical organization, many areas of the extrastriate cortex are dedicated to object categories. These models often assume an early processing stage for the detection of category membership. Can functional imaging isolate areas responsible for detection of members of a category, such as faces or letters? We consider whether responses in three different areas (two selective for faces and one selective for letters) support category detection. Activity in these areas habituates to the repeated presentation of one exemplar more than to the presentation of different exemplars of the same category, but only for the category for which the area is selective. Thus, these areas appear to play computational roles more complex than detection, processing stimuli at the individual level. Drawing from prior work, we suggest that face-selective areas may be involved in the perception of faces at the individual level, whereas letter-selective regions may be tuning themselves to font information in order to recognize letters more efficiently.

Localized necking in thin sheets

Abstract: B y using a simplified constitutive model of a pointed vertex on subsequent yield loci, namely, such that the equations of deformation-theory of rigid-plastic solids apply for fully-active stress increments, the onset of localized necking under biaxial stretching has been predicted. The predictions agree reasonably well with reported experimental observations. Since localized necking under biaxial stretching of a uniform and homogeneous sheet is impossible when flow theories of plasticity with smooth yield-loci are used, this result supports the hypothesis of vertex-formation on the yield locus under continued plastic flow. The implications of this conclusion with respect to the study of the inception of ductile fracture in solids, viewed as a material instability, may be far-reaching. Still, explanations based on a smooth yield-locus but small initial inhomogeneities cannot be ruled out, and both initial imperfections and yield-vertex effects may contribute in general to localization instabilities.