63 research outputs found

    Small Area Estimation of Latent Economic Well-being

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    © The Author(s) 2019. Small area estimation (SAE) plays a crucial role in the social sciences due to the growing need for reliable and accurate estimates for small domains. In the study of well-being, for example, policy makers need detailed information about the geographical distribution of a range of social indicators. We investigate data dimensionality reduction using factor analysis models and implement SAE on the factor scores under the empirical best linear unbiased prediction approach. We contrast this approach with the standard approach of providing a dashboard of indicators or a weighted average of indicators at the local level. We demonstrate the approach in a simulation study and a real data application based on the European Union Statistics for Income and Living Conditions for the municipalities of Tuscany

    The MOBILIZE Boston Study: Design and methods of a prospective cohort study of novel risk factors for falls in an older population

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    <p>Abstract</p> <p>Background</p> <p>Falls are the sixth leading cause of death in elderly people in the U.S. Despite progress in understanding risk factors for falls, many suspected risk factors have not been adequately studied. Putative risk factors for falls such as pain, reductions in cerebral blood flow, somatosensory deficits, and foot disorders are poorly understood, in part because they pose measurement challenges, particularly for large observational studies.</p> <p>Methods</p> <p>The MOBILIZE Boston Study (MBS), an NIA-funded Program Project, is a prospective cohort study of a unique set of risk factors for falls in seniors in the Boston area. Using a door-to-door population-based recruitment, we have enrolled 765 persons aged 70 and older. The baseline assessment was conducted in 2 segments: a 3-hour home interview followed within 4 weeks by a 3-hour clinic examination. Measures included pain, cerebral hemodynamics, and foot disorders as well as established fall risk factors. For the falls follow-up, participants return fall calendar postcards to the research center at the end of each month. Reports of falls are followed-up with a telephone interview to assess circumstances and consequences of each fall. A second assessment is performed 18 months following baseline.</p> <p>Results</p> <p>Of the 2382 who met all eligibility criteria at the door, 1616 (67.8%) agreed to participate and were referred to the research center for further screening. The primary reason for ineligibility was inability to communicate in English. Results from the first 600 participants showed that participants are largely representative of seniors in the Boston area in terms of age, sex, race and Hispanic ethnicity. The average age of study participants was 77.9 years (s.d. 5.5) and nearly two-thirds were women. The study cohort was 78% white and 17% black. Many participants (39%) reported having fallen at least once in the year before baseline.</p> <p>Conclusion</p> <p>Our results demonstrate the feasibility of conducting comprehensive assessments, including rigorous physiologic measurements, in a diverse population of older adults to study non-traditional risk factors for falls and disability. The MBS will provide an important new data resource for examining novel risk factors for falls and mobility problems in the older population.</p

    Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

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    We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

    Blindness and Visual Impairment in an American Urban Population: The Baltimore Eye Survey

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    Data on the prevalence of blindness and visual impairment in multiracial urban populations of the United States are not readily available. The Baltimore Eye Survey was designed to address this lack of information and provide estimates of prevalence in age-race subgroups that had not been well studied in the past. A population-based sample of 5300 blacks and whites from east Baltimore, Md, received an ophthalmologic screening examination that included detailed visual acuity measurements. Blacks had, on average, a twofold excess prevalence of blindness and visual impairment than whites, irrespective of definition. Rates rose dramatically with age for all definitions of vision loss, but there was no difference in prevalence by sex. More than 50% of subjects improved their presenting vision after refractive correction, with 7.5% improving three or more lines. Rates in Baltimore are as high or higher than those reported from previous studies. National projections indicate that greater than 3 million persons are visually impaired, 890 000 of whom are bilaterally blind by US definitions. © 1990, American Medical Association. All rights reserved

    Racial Variations in the Prevalence of Primary Open-angle Glaucoma: The Baltimore Eye Survey

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    Objective.—To compare the prevalence of primary open-angle glaucoma between black and white Americans. Design, Setting, and Participants.—The design was a population-based prevalence survey of a noninstitutionalized black and white population aged 40 years or older from the eastern and southeastern health districts of Baltimore, Md. A multistage random sampling strategy was used to identify 7104 eligible participants, of whom 5308 (2395 blacks, 2913 whites) received an ophthalmologic screening examination. Those with abnormalities were referred for definitive diagnostic evaluation. Main Outcome Measure.—Primary open-angle glaucoma was defined based on evidence of glaucomatous optic nerve damage, including abnormal visual fields and/or severe optic disc cupping, and was independent of intraocular pressure. Main Results.—Age-adjusted prevalence rates for primary open-angle glaucoma were four to five times higher in blacks as compared with whites. Rates among blacks ranged from 1.23% in those aged 40 through 49 years to 11.26% in those 80 years or older, whereas rates for whites ranged from 0.92% to 2.16%, respectively. There was no difference in rates of primary open-angle glaucoma between men and women for either blacks or whites in this population. Based on these data, an estimated 1.6 million persons aged 40 years or older in the United States have primary open-angle glaucoma. Conclusions.—Black Americans are at higher risk of primary open-angle glaucoma than their white neighbors. This may reflect an underlying genetic susceptibility to this disease and indicates that additional efforts are needed to identify and treat this sight-threatening disorder in high-risk communities. © 1991, American Medical Association. All rights reserved

    Electrical stimulation promotes motoneuron regeneration without increasing its speed or conditioning the neuron

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    Motoneurons reinnervate the distal stump at variable rates after peripheral nerve transection and suture. In the rat femoral nerve model, reinnervation is already substantial 3 weeks after repair, but is not completed for an additional 7 weeks. However, this “staggered regeneration ” can be temporally compressed by application of 20 Hz electrical stimulation to the nerve for 1 hr. The present experiments explore two possible mechanisms for this stimulation effect: (1) synchronization of distal stump reinnervation and (2) enhancement of regeneration speed. The first possibility was investigated by labeling all motoneurons that have crossed the repair at intervals from 4 d to 4 weeks after rat femoral nerve transection and suture. Although many axons did not cross until 3–4 weeks after routine repair, stimulation significantly increased the number crossing at 4 and 7 d, with only a few crossing after 2 weeks. Regeneration speed was studied by radioisotope labeling of transported proteins and by anterograde labeling of regenerating axons, and was not altered by stimulation. Attempts to condition the neuron by stimulating the femoral nerve 1 week before injury were also without effect. Electrical stimulation thus promotes the onset of motor axon regeneration without increasing its speed. This finding suggests a combined approach to improving the outcome of nerve repair, beginning with stimulation to recruit all motoneurons across the repair, followed by other treatments to speed and prolong axonal elongation. Key words: electrical stimulation; peripheral nerve; anterograde tracing; BDNF; conditioning; neurobiotin In the mid-eighteenth century, electrical stimulation became a popular treatment for disorders of the nervous system (Du Bois

    A Bunyamwera Virus Minireplicon System in Mosquito Cells

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    Artificial minigenomes are powerful tools for studying the replication and transcription of negative-strand RNA viruses. Bunyamwera virus (BUN; genus Orthobunyavirus, family Bunyaviridae) is an arbovirus that shows fundamental biological differences when replicating in mammalian versus mosquito cells. To study BUN RNA synthesis in mosquito cells, we developed a bacteriophage T7 RNA polymerase-based minireplicon system similar to that described previously for mammalian cells. An Aedes albopictus C6/36-derived mosquito cell line stably expressing T7 RNA polymerase was established. Viral proteins and artificial minigenomes (containing Renilla luciferase as a reporter) were transcribed and expressed in these cells from transfected T7 promoter-containing plasmids. Transcription of the minigenome required two viral proteins, the nucleocapsid protein N and the RNA-dependent RNA polymerase L, a situation similar to that in mammalian cells. However, unlike the situation in mammalian cells, the viral polymerase was not inhibited by the viral nonstructural protein NSs. We also report that promoter strength is different for vertebrate versus invertebrate cells. The development of this system opens the way for a detailed comparison of bunyavirus replication in cells of disparate phylogeny
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