4,044 research outputs found

    Compounded Disadvantage: Race, Incarceration, and Wage Growth

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    Based on 14-year panel data on ex-prisoners, this paper reports the impact of incarceration on future job prospects. Black men, in addition to facing greater risk of ending up in prison, are more negatively affected by imprisonment than white men. The expansion of the U.S. criminal justice system is therefore responsible for compounding the disadvantages of African Americans

    LoCoH: nonparameteric kernel methods for constructing home ranges and utilization distributions.

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    Parametric kernel methods currently dominate the literature regarding the construction of animal home ranges (HRs) and utilization distributions (UDs). These methods frequently fail to capture the kinds of hard boundaries common to many natural systems. Recently a local convex hull (LoCoH) nonparametric kernel method, which generalizes the minimum convex polygon (MCP) method, was shown to be more appropriate than parametric kernel methods for constructing HRs and UDs, because of its ability to identify hard boundaries (e.g., rivers, cliff edges) and convergence to the true distribution as sample size increases. Here we extend the LoCoH in two ways: "fixed sphere-of-influence," or r-LoCoH (kernels constructed from all points within a fixed radius r of each reference point), and an "adaptive sphere-of-influence," or a-LoCoH (kernels constructed from all points within a radius a such that the distances of all points within the radius to the reference point sum to a value less than or equal to a), and compare them to the original "fixed-number-of-points," or k-LoCoH (all kernels constructed from k-1 nearest neighbors of root points). We also compare these nonparametric LoCoH to parametric kernel methods using manufactured data and data collected from GPS collars on African buffalo in the Kruger National Park, South Africa. Our results demonstrate that LoCoH methods are superior to parametric kernel methods in estimating areas used by animals, excluding unused areas (holes) and, generally, in constructing UDs and HRs arising from the movement of animals influenced by hard boundaries and irregular structures (e.g., rocky outcrops). We also demonstrate that a-LoCoH is generally superior to k- and r-LoCoH (with software for all three methods available at http://locoh.cnr.berkeley.edu)

    Long-term sedimentary recycling of rare sulphur isotope anomalies

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    The accumulation of substantial quantities of O_2 in the atmosphere has come to control the chemistry and ecological structure of Earth’s surface. Non-mass-dependent (NMD) sulphur isotope anomalies in the rock record are the central tool used to reconstruct the redox history of the early atmosphere. The generation and initial delivery of these anomalies to marine sediments requires low partial pressures of atmospheric O_2 (PO_2; refs 2, 3), and the disappearance of NMD anomalies from the rock record 2.32 billion years ago is thought to have signalled a departure from persistently low atmospheric oxygen levels (less than about 10^(−5) times the present atmospheric level) during approximately the first two billion years of Earth’s history. Here we present a model study designed to describe the long-term surface recycling of crustal NMD anomalies, and show that the record of this geochemical signal is likely to display a ‘crustal memory effect’ following increases in atmospheric PO_2 above this threshold. Once NMD anomalies have been buried in the upper crust they are extremely resistant to removal, and can be erased only through successive cycles of weathering, dilution and burial on an oxygenated Earth surface. This recycling results in the residual incorporation of NMD anomalies into the sedimentary record long after synchronous atmospheric generation of the isotopic signal has ceased, with dynamic and measurable signals probably surviving for as long as 10–100 million years subsequent to an increase in atmospheric PO_2 to more than 10^(−5) times the present atmospheric level. Our results can reconcile geochemical evidence for oxygen production and transient accumulation with the maintenance of NMD anomalies on the early Earth, and suggest that future work should investigate the notion that temporally continuous generation of new NMD sulphur isotope anomalies in the atmosphere was likely to have ceased long before their ultimate disappearance from the rock record

    The Use of CFSE-like Dyes for Measuring Lymphocyte Proliferation : Experimental Considerations and Biological Variables

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    The measurement of CFSE dilution by flow cytometry is a powerful experimental tool to measure lymphocyte proliferation. CFSE fluorescence precisely halves after each cell division in a highly predictable manner and is thus highly amenable to mathematical modelling. However, there are several biological and experimental conditions that can affect the quality of the proliferation data generated, which may be important to consider when modelling dye dilution data sets. Here we overview several of these variables including the type of fluorescent dye used to monitor cell division, dye labelling methodology, lymphocyte subset differences, in vitro versus in vivo experimental assays, cell autofluorescence, and dye transfer between cells.This work was supported by a Project Grant to BQ and CP and a Program Grant to CP from the National Health and Medical Research Council (NHMRC) of Australia

    Which interventions increase hearing protection behaviors during noisy recreational activities? A systematic review

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    From Springer Nature via Jisc Publications RouterHistory: received 2020-02-10, accepted 2020-08-19, registration 2020-08-20, pub-electronic 2020-09-13, online 2020-09-13, collection 2020-12Publication status: PublishedFunder: Manchester Biomedical Research Centre; doi: http://dx.doi.org/10.13039/100014653; Grant(s): N/AAbstract: Background: Hearing loss and tinnitus are global concerns that can be reduced through hearing protection behaviors (e.g., earplug use). Little is known about the effectiveness of interventions to increase hearing protection use in recreational domains. For the first time we review systematically the effectiveness of such interventions. Methods: Systematic searches of nine databases, as well as grey literature and hand-searching, were conducted. Any study design was included if it assessed quantitatively a purposeful attempt to increase hearing protection in recreational settings. Studies were excluded if they assessed noise exposure from occupational sources and headphones/earphones, as these have been reviewed elsewhere. PROSPERO protocol: CRD42018098573. Results: Eight studies were retrieved following the screening of 1908 articles. Two pretest-posttest studies detected a small to medium effect (d ≥ 0·3 ≤ 0·5), one a small effect (d ~ =0·2) and two no real effect. Three posttest experimental studies detected small to medium effects (d ≥ 0·3 ≤ 0·5). Studies were rated as “poor quality” and 17 out of a possible 93 behavior change techniques were coded, with the majority targeting the intervention function ‘education’. Conclusions: Hearing loss and tinnitus due to recreational noise exposure are major public health concerns yet very few studies have examined preventive interventions. The present systematic review sets the agenda for the future development and testing of evidence-based interventions designed to prevent future hearing loss and tinnitus caused by noise in recreational settings, by recommending systematic approaches to intervention design, and implementation of intervention functions beyond education, such as incentivization, enablement and modeling

    Method and Apparatus for Non-Destructive Evaluation of Materials

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    Methods and apparatus for characterizing composite materials for manufacturing quality assurance (QA), periodic inspection during the useful life, or for forensic analysis/material testing. System are provided that relate eddy-current sensor responses to the fiber layup of a composite structure, the presence of impact damage on a composite structure with or without a metal liner, volumetric stress within the composite, fiber tow density, and other NDE inspection requirements. Also provided are systems that determine electromagnetic material properties and material dimensions of composite materials from capacitive sensor inspection measurements. These properties are related to the presence of buried defects in non-conductive composite materials, moisture ingress, aging of the material due to service or environmental/thermal exposure, or changes in manufacturing quality

    Mineral Acquisition from Clay by Budongo Forest Chimpanzees

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    Chimpanzees of the Sonso community, Budongo Forest, Uganda were observed eating clay and drinking clay-water from waterholes. We show that clay, clay-rich water, and clay obtained with leaf sponges, provide a range of minerals in different concentrations. The presence of aluminium in the clay consumed indicates that it takes the form of kaolinite. We discuss the contribution of clay geophagy to the mineral intake of the Sonso chimpanzees and show that clay eaten using leaf sponges is particularly rich in minerals. We show that termite mound soil, also regularly consumed, is rich in minerals. We discuss the frequency of clay and termite soil geophagy in the context of the disappearance from Budongo Forest of a formerly rich source of minerals, the decaying pith of Raphia farinifera palms

    Method and Apparatus for Non-Destructive Evaluation of Materials

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    Methods and apparatus for characterizing composite materials for manufacturing quality assurance (QA), periodic inspection during the useful life, or for forensic analysis/material testing. System are provided that relate eddy-current sensor responses to the fiber layup of a composite structure, the presence of impact damage on a composite structure with or without a metal liner, volumetric stress within the composite, fiber tow density, and other NDE inspection requirements. Also provided are systems that determine electromagnetic material properties and material dimensions of composite materials from capacitive sensor inspection measurements. These properties are related to the presence of buried defects in non-conductive composite materials, moisture ingress, aging of the material due to service or environmental/thermal exposure, or changes in manufacturing quality

    Response to Questions in the First White Paper, \u27Modernizing the Communications Act\u27

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    The House Energy and Commerce Committee has begun a process to review and update the Communications Act of 1934, last revised in any material way in 1996. As the Committee begins the review process, this paper responds to questions posed by the Committee that all relate, in fundamental ways, to the question: What should a modern Communications Act look like? The Response advocates a clean slate approach under which the regulatory silos that characterize the current statute would be eliminated, along with almost all of the ubiquitous \u27public interest\u27 delegation of authority found throughout the Communications Act. The replacement regime would have at its core a new competition-based standard that, except in limited circumstances, would require that the FCC\u27s regulatory activities be tied to findings of consumer harm resulting from lack of sufficient competition. The FCC\u27s authority to adopt broad anticipatory rules on an ex ante basis would be substantially circumscribed, and the agency would be required to rely more heavily than is presently the case on ex post adjudication of individual complaints alleging specific abuses of market power and consumer harm. Some aspects of the FCC\u27s current jurisdiction, such as privacy and data security regulation, might be transferred to the FTC in light of the FTC\u27s institutional competence in these areas

    Response to Questions in the First White Paper, \u27Modernizing the Communications Act\u27

    Get PDF
    The House Energy and Commerce Committee has begun a process to review and update the Communications Act of 1934, last revised in any material way in 1996. As the Committee begins the review process, this paper responds to questions posed by the Committee that all relate, in fundamental ways, to the question: What should a modern Communications Act look like? The Response advocates a clean slate approach under which the regulatory silos that characterize the current statute would be eliminated, along with almost all of the ubiquitous \u27public interest\u27 delegation of authority found throughout the Communications Act. The replacement regime would have at its core a new competition-based standard that, except in limited circumstances, would require that the FCC\u27s regulatory activities be tied to findings of consumer harm resulting from lack of sufficient competition. The FCC\u27s authority to adopt broad anticipatory rules on an ex ante basis would be substantially circumscribed, and the agency would be required to rely more heavily than is presently the case on ex post adjudication of individual complaints alleging specific abuses of market power and consumer harm. Some aspects of the FCC\u27s current jurisdiction, such as privacy and data security regulation, might be transferred to the FTC in light of the FTC\u27s institutional competence in these areas
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