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.

Toxicity testing in the 21st century: a vision and a strategy

Abstract: With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U.S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal usage by transitioning from current expensive and lengthy in vivo testing with qualitative endpoints to in vitro toxicity pathway assays on human cells or cell lines using robotic high-throughput screening with mechanistic quantitative parameters. Risk assessment in the exposed human population would focus on avoiding significant perturbations in these toxicity pathways. Computational systems biology models would be implemented to determine the dose-response models of perturbations of pathway function. Extrapolation of in vitro results to in vivo human blood and tissue concentrations would be based on pharmacokinetic models for the given exposure condition. This practice would enhance human relevance of test results, and would cover several test agents, compared to traditional toxicological testing strategies. As all the tools that are necessary to implement the vision are currently available or in an advanced stage of development, the key prerequisites to achieving this paradigm shift are a commitment to change in the scientific community, which could be facilitated by a broad discussion of the vision, and obtaining necessary resources to enhance current knowledge of pathway perturbations and pathway assays in humans and to implement computational systems biology models. Implementation of these strategies would result in a new toxicity testing paradigm firmly based on human biology.

Seven-year wilkinson microwave anisotropy probe (wmap *) observations: sky maps, systematic errors, and basic results

Abstract: New full-sky temperature and polarization maps based on seven years of data from WMAP are presented. The new results are consistent with previous results, but have improved due to reduced noise from the additional integration time, improved knowledge of the instrument performance, and improved data analysis procedures. The improvements are described in detail. The seven-year data set is well fit by a minimal six-parameter flat ?CDM model. The parameters for this model, using the WMAP data in conjunction with baryon acoustic oscillation data from the Sloan Digital Sky Survey and priors on H 0 from Hubble Space Telescope observations, are ? b h 2 = 0.02260 ? 0.00053, ? c h 2 = 0.1123 ? 0.0035, ?? = 0.728+0.015 ?0.016, ns = 0.963 ? 0.012, ? = 0.087 ? 0.014, and ?8 = 0.809 ? 0.024 (68% CL uncertainties). The temperature power spectrum signal-to-noise ratio per multipole is greater that unity for multipoles ? 919, allowing a robust measurement of the third acoustic peak. This measurement results in improved constraints on the matter density, ? m h 2 = 0.1334+0.0056 ?0.0055, and the epoch of matter-radiation equality, z eq = 3196+134 ?133, using WMAP data alone. The new WMAP data, when combined with smaller angular scale microwave background anisotropy data, result in a 3? detection of the abundance of primordial helium, Y He = 0.326 ? 0.075. When combined with additional external data sets, the WMAP data also yield better determinations of the total mass of neutrinos, ?m ? ? 0.58 eV(95%CL), and the effective number of neutrino species, N eff = 4.34+0.86 ?0.88. The power-law index of the primordial power spectrum is now determined to be ns = 0.963 ? 0.012, excluding the Harrison-Zel'dovich-Peebles spectrum by >3?. These new WMAP measurements provide important tests of big bang cosmology.

Neurodevelopmental and growth impairment among extremely low-birth-weight infants with neonatal infection.

Abstract: ContextNeonatal infections are frequent complications of extremely low-birth-weight (ELBW) infants receiving intensive care.ObjectiveTo determine if neonatal infections in ELBW infants are associated with increased risks of adverse neurodevelopmental and growth sequelae in early childhood.Design, Setting, and ParticipantsInfants weighing 401 to 1000 g at birth (born in 1993-2001) were enrolled in a prospectively collected very low-birth-weight registry at academic medical centers participating in the National Institute of Child Health and Human Development Neonatal Research Network. Neurodevelopmental and growth outcomes were assessed at a comprehensive follow-up visit at 18 to 22 months of corrected gestational age and compared by infection group. Eighty percent of survivors completed the follow-up visit and 6093 infants were studied. Registry data were used to classify infants by type of infection: uninfected (n = 2161), clinical infection alone (n = 1538), sepsis (n = 1922), sepsis and necrotizing enterocolitis (n = 279), or meningitis with or without sepsis (n = 193).Main Outcome MeasuresCognitive and neuromotor development, neurologic status, vision and hearing, and growth (weight, length, and head circumference) were assessed at follow-up.ResultsThe majority of ELBW survivors (65%) had at least 1 infection during their hospitalization after birth. Compared with uninfected infants, those in each of the 4 infection groups were significantly more likely to have adverse neurodevelopmental outcomes at follow-up, including cerebral palsy (range of significant odds ratios [ORs], 1.4-1.7), low Bayley Scales of Infant Development II scores on the mental development index (ORs, 1.3-1.6) and psychomotor development index (ORs, 1.5-2.4), and vision impairment (ORs, 1.3-2.2). Infection in the neonatal period was also associated with impaired head growth, a known predictor of poor neurodevelopmental outcome.ConclusionsThis large cohort study suggests that neonatal infections among ELBW infants are associated with poor neurodevelopmental and growth outcomes in early childhood. Additional studies are needed to elucidate the pathogenesis of brain injury in infants with infection so that novel interventions to improve these outcomes can be explored.

E‐Government and the Transformation of Service Delivery and Citizen Attitudes

Abstract: The impact of new technology on public-sector service delivery and citizens' attitudes about government has long been debated by political observers. This article assesses the consequences ofe-government for service delivery, democratic responsiveness, and public attitudes over the last three years. Research examines the content of e-government to investigate whether it is taking advantage of the interactive features of the World Wide Web to improve service delivery, democratic responsiveness, and public outreach. In addition, a national public opinion survey examines the ability of e-government to influence citizens' views about government and their confidence in the effectiveness of service delivery. Using both Web site content as well as public assessments, I argue that, in some respects, the e-government revolution has fallen short of its potential to transform service delivery and public trust in government. It does, however, have the possibility of enhancing democratic responsiveness and boosting beliefs that government is effective.