Stony Brook University

About: Stony Brook University is a education organization based out in Stony Brook, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 32534 authors who have published 68218 publications receiving 3035131 citations. The organization is also known as: State University of New York at Stony Brook & SUNY Stony Brook.

Efficient collision detection using bounding volume hierarchies of k-DOPs

Abstract: Collision detection is of paramount importance for many applications in computer graphics and visualization. Typically, the input to a collision detection algorithm is a large number of geometric objects comprising an environment, together with a set of objects moving within the environment. In addition to determining accurately the contacts that occur between pairs of objects, one needs also to do so at real-time rates. Applications such as haptic force feedback can require over 1000 collision queries per second. We develop and analyze a method, based on bounding-volume hierarchies, for efficient collision detection for objects moving within highly complex environments. Our choice of bounding volume is to use a discrete orientation polytope (k-DOP), a convex polytope whose facets are determined by halfspaces whose outward normals come from a small fixed set of k orientations. We compare a variety of methods for constructing hierarchies (BV-trees) of bounding k-DOPs. Further, we propose algorithms for maintaining an effective BV-tree of k-DOPs for moving objects, as they rotate, and for performing fast collision detection using BV-trees of the moving objects and of the environment. Our algorithms have been implemented and tested. We provide experimental evidence showing that our approach yields substantially faster collision detection than previous methods.

Long story short: the serotonin transporter in emotion regulation and social cognition.

Abstract: The gene encoding the serotonin transporter (5-HTT) contains a regulatory variation that has been associated with anxiety-related traits and susceptibility for depression. Here we highlight recent discoveries related to allelic variation of 5-HTT function with respect to emotion regulation and social behavior, drawing from an interdisciplinary perspective of behavioral genetics and cognitive neuroscience. Following a reductionistic path that leads from gene-behavior association studies to neuroimaging and epigenetic studies, we compare two models of 5-HTT-dependent modulation of brain activity and discuss the role of life stress experience in modifying 5-HTT function in the brain. Integration of these findings suggests that the impact of the 5-HTT gene on behavior is much broader than is commonly appreciated and may have a role in social cognition.

Use of adeno-associated virus as a general transduction vector for mammalian cells.

Abstract: Adeno-associated virus (AAV) is a human virus that can be propagated either as an integrated provirus or by lytic infection (Atchison et al. 1965; Hoggan et al. 1966, 1972). The ability to form a latent infection appears to be an integral part of the AAV life cycle. Except under special circumstances (Yacobson et al. 1987; Schlehofer et al. 1986; Yalkinoglu et al. 1988), AAV requires the presence of a helper virus to initiate a productive viral infection (Fig. 1). Members of either the herpes or adenovirus families can provide the necessary helper functions (Atchison et al. 1965; Melnick et al. 1965; Hoggan et al. 1966; Buller et al. 1981; McPherson et al. 1985) and vaccinia virus can provide at least partial helper function (Schlehofer et al. 1986). In the absence of a helper virus AAV produces no progeny virus, but instead integrates into a host chromosome (Hoggan et al. 1972; Berns et al. 1975; Handa et al. 1977; Cheung et al. 1980). With rare exceptions, AAV proviruses appear to be stable. However, if a cell line that is carrying an AAV provirus (Fig. 1) is subsequently superinfected with a helper virus, the AAV genome is excised and proceeds through a normal productive infection (Hoggan et al. 1972; Cheung et al. 1980). This ability to establish a latent infection which can later be rescued appears to be a mechanism for ensuring the survival of AAV in the absence of a helper virus. The unusual life cycle of AAV has led a number of parvovirus laboratories to explore the possibility of using AAV as a general mammalian transduction vector.

Effect of estrogen plus progestin on global cognitive function in postmenopausal women: the Women's Health Initiative Memory Study: a randomized controlled trial.

Abstract: ContextObservational studies have suggested that postmenopausal hormone treatment may improve cognitive function, but data from randomized clinical trials have been sparse and inconclusive The Women's Health Initiative Memory Study (WHIMS) is an ancillary study of the Women's Health Initiative (WHI) hormone therapy trials On July 8, 2002, the estrogen plus progestin therapy in the WHI trial was discontinued because of certain increased health risks for womenObjectiveTo determine whether estrogen plus progestin therapy protects global cognitive function in older postmenopausal womenDesign, Setting, and ParticipantsA randomized, double-blind, placebo-controlled clinical trial, WHIMS is an ancillary study of geographically diverse, community-dwelling women aged 65 years or older from 39 of 40 clinical centers within the WHI estrogen plus progestin trial that started in June 1995 Of 4894 eligible postmenopausal women aged 65 years or older and free of probable dementia at baseline, 4532 (926%) were enrolled in the estrogen plus progestin component of WHIMS A total of 4381 participants (967%) provided at least 1 valid cognitive function score between June 1995 and July 8, 2002InterventionsParticipants received either 1 daily tablet containing 0625 mg of conjugated equine estrogen with 25 mg of medroxyprogesterone acetate (n = 2145) or matching placebo (n = 2236)Main Outcome MeasureGlobal cognitive function measured annually with the Modified Mini-Mental State ExaminationResultsThe Modified Mini-Mental State Examination mean total scores in both groups increased slightly over time (mean follow-up of 42 years) Women in the estrogen plus progestin group had smaller average increases in total scores compared with women receiving placebo (P = 03), but these differences were not clinically important Removing women by censoring them after adjudicated dementia, mild cognitive impairment, or stroke, and nonadherence to study protocol, did not alter the findings Prior hormone therapy use and duration of prior use did not affect the interpretation of the results, nor did timing of prior hormone therapy initiation with respect to the final menstrual period More women in the estrogen plus progestin group had a substantial and clinically important decline (≥2 SDs) in Modified Mini-Mental State Examination total score (67%) compared with the placebo group (48%) (P = 008)ConclusionsAmong postmenopausal women aged 65 years or older, estrogen plus progestin did not improve cognitive function when compared with placebo While most women receiving estrogen plus progestin did not experience clinically relevant adverse effects on cognition compared with placebo, a small increased risk of clinically meaningful cognitive decline occurred in the estrogen plus progestin group

From Social to Political Identity: A Critical Examination of Social Identity Theory

Abstract: Interest in the concept of identity has grown exponentially within both the humanities and social sciences, but the discussion of identity has had less impact than might be expected on the quantitative study of political behavior in general and on political psychology more specifically. One of the approaches that holds the most promise for political psychologists is social identity theory, as reflected in the thinking of Henri Tajfel, John Turner, and colleagues. Although the theory addresses the kinds of problems of interest to political psychologists, it has had limited impact on political psychology because of social identity theorists' disinclination to examine the sources of social identity in a real world complicated by history and culture. In this review, four key issues are examined that hinder the successful application of social identity theory to political phenomena. These key issues are the existence of identity choice, the subjective meaning of identities, gradations in identity strength, and the considerable stability of many social and political identities.