311 research outputs found

    Franz Boas and the Columbian Field Museum

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    The Late Nineteenth Century was a period of major flux within the world of American anthropology. Two major centers of power had emerged within the nascent field. Federally sponsored anthropologists clashed with academic institutions, especially those associated with Harvard’s Frederic Ward Putnam. These two bodies found themselves at odds over methodological design and the theoretical frameworks supporting their research. These issues would span the breadth of anthropology as a field, but nowhere was it more visible than in the scope of museum studies. Public displays of anthropological thought were the most direct way that scholars were able to present their findings to the general public. The ideas that these displays conveyed would inform the nation’s public on the world around them, and their rightful place in it. Federal anthropologists and their subscription to Social Evolutionary theory painted all human societies as existing on the same linear quest towards an idealized civilization. Putnam and his followers believed that societies needed to be classified by the unique geographical and temporal spaces in which they occupied. The issues of museum management would come to a head in the months following the Chicago World’s Columbian Exhibition with the formation of the Columbian Field Museum. The newly established museum, and the city of Chicago itself, became a hotly contested center for both groups hoping to establish a cultural foothold in the heart of America. It is within this context that Franz Boas, a pivotal figure within anthropology, and his involvement in not only the museum but the larger debate as a whole is investigated. Through an analysis of Franz Boas’ early career, this paper explores the social, methodological, and racial divides that defined early American anthropology and its place within the Nation’s narrative

    Slow Equilibration between Spectroscopically Distinct Trap States in Reduced TiO\u3csub\u3e2\u3c/sub\u3e Nanoparticles

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    © 2017 American Chemical Society. Understanding the nature of charge carriers in nanoscale titanium dioxide is important for its use in solar energy conversion, photocatalysis, and other applications. UV-irradiation of aqueous, colloidal TiO2 nanoparticles in the presence of methanol gives highly reduced suspensions. Two distinct types of electron traps were observed and characterized by EPR and optical spectroscopies. The relative populations of the states depend on temperature, indicating a small energy difference, ΔH° = 3.0 ± 0.6 kcal/mol (130 ± 30 meV). Interconversion between the electron traps occurs slowly over the course of minutes to hours within the temperature range studied here, 0-50 °C. The slow time scale implies that interconversion involves changes in structure or stoichiometry, not just the movement of electrons. This occurrence of slow structural modification with changes in trap state occupancy is likely a general feature of reduced TiO2 systems at thermodynamic equilibria or photostationary states and should be considered in the design of TiO2-containing devices

    Effects of aging and dual tasking on step adjustments to perturbations in visually cued walking

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    Making step adjustments is an essential component of walking. However, the ability to make step adjustments may be compromised when the walker's attentional capacity is limited. This study compared the effects of aging and dual tasking on step adjustments in response to stepping-target perturbations during visually cued treadmill walking. Fifteen older adults (69.4 ± 5.0 years; mean ± SD) and fifteen young adults (25.4 ± 3.0 years) walked at a speed of 3 km/h on a treadmill. Both groups performed visually cued step adjustments in response to unpredictable shifts of projected stepping targets in forward (FW), backward (BW) or sideward (SW) directions, at different levels of task difficulty [which increased as the available response distance (ARD) decreased], and with and without dual tasking (auditory Stroop task). In both groups, step adjustments were smaller than required. For FW and BW shifts, older adults undershot more under dual-task conditions. For these shifts, ARD affected the age groups differentially. For SW shifts, larger errors were found for older adults, dual tasking and the most difficult ARD. Stroop task performance did not differ between groups in all conditions. Older adults have more difficulty than young adults to make corrective step adjustments while walking, especially under dual-tasking conditions. Furthermore, they seemed to prioritize the cognitive task over the step adjustment task, a strategy that may pose aging populations at a greater fall risk. For comparable task difficulty, the older adults performed considerably worse than the young adults, indicating a decreased ability to adjust steps under time pressure

    State of Vermont Health Care Financing Plan Beginning Calendar Year 2017 Analysis

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    This report, prepared for the Vermont Agency of Administration, details the costs and coverage of a single-payer system in Vermont, and explained that the state must develop new financing mechanisms that raise $1.6 billion to fund single-payer. It was produced in partnership with Wakely Consulting Group Inc. However, on December 17, 2014, Gov. Peter Shumlin announced that now is not the right time to overhaul health care financing and delivery in Vermont

    Governance in the Eurozone: A Strategic Relational Approach

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    Functional neuroimaging studies in adults show that aggression involves reduced brain communication between subcortical and cortical areas dedicated to motivation and control, respectively. Prior research indicates that sex steroid hormone production during adolescence negatively influences the rapid development of white matter connectivity between subcortical and cortical areas during adolescence and may potentiate aggression. Here, we tested this hypothesis in 258 participants between 8 and 25 years of age by using Diffusion Weighted Imaging to examine the microstructure of white matter connections within the fronto-temporal-subcortical network. Trait aggression was measured using the Buss Perry Aggression Questionnaire and testosterone and estradiol levels were measured in saliva. Results indicated that higher levels of testosterone were associated with less white matter integrity within the fronto-temporal-subcortical network (i.e., higher mean diffusivity [MD] longitudinal [LD], and radial diffusivity [RD]). Furthermore, lower fractional anisotropy and higher MD, LD, and RD values within this network increased expressive forms of aggression and reduced inhibited forms of aggression (hostility). Our study indicates higher levels of testosterone relating to lower quality of structural cortical-subcortical connectivity, arguably resulting in a shift from inhibited towards expressive forms of aggressio

    Behavioral Economic Measurement of Cigarette Demand: A Descriptive Review of Published Approaches to the Cigarette Purchase Task

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    The cigarette purchase task (CPT) is a behavioral economic method for assessing demand for cigarettes. Growing interest in behavioral correlates of tobacco use in clinical and general populations as well as empirical efforts to inform policy has seen an increase in published articles employing the CPT. Accordingly, an examination of the published methods and procedures for obtaining these behavioral economic metrics is timely. The purpose of this investigation was to provide a review of published approaches to using the CPT. We searched specific Boolean operators ([“behavioral economic” AND “purchase task”] OR [“demand” AND “cigarette”]) and identified 49 empirical articles published through the year 2018 that reported administering a CPT. Articles were coded for participant characteristics (e.g., sample size, population type, age), CPT task structure (e.g., price framing, number and sequence of prices; vignettes, contextual factors), and data analytic approach (e.g., method of generating indices of cigarette demand). Results of this review indicate no standard approach to administering the CPT and underscore the need for replicability of these behavioral economic measures for the purpose of guiding clinical and policy decisions

    A Cautionary Tale: MARVELS Brown Dwarf Candidate Reveals Itself To Be A Very Long Period, Highly Eccentric Spectroscopic Stellar Binary

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    We report the discovery of a highly eccentric, double-lined spectroscopic binary star system (TYC 3010-1494-1), comprising two solar-type stars that we had initially identified as a single star with a brown dwarf companion. At the moderate resolving power of the MARVELS spectrograph and the spectrographs used for subsequent radial-velocity (RV) measurements (R ~ <30,000), this particular stellar binary mimics a single-lined binary with an RV signal that would be induced by a brown dwarf companion (Msin(i)~50 M_Jup) to a solar-type primary. At least three properties of this system allow it to masquerade as a single star with a very low-mass companion: its large eccentricity (e~0.8), its relatively long period (P~238 days), and the approximately perpendicular orientation of the semi-major axis with respect to the line of sight (omega~189 degrees). As a result of these properties, for ~95% of the orbit the two sets of stellar spectral lines are completely blended, and the RV measurements based on centroiding on the apparently single-lined spectrum is very well fit by an orbit solution indicative of a brown dwarf companion on a more circular orbit (e~0.3). Only during the ~5% of the orbit near periastron passage does the true, double-lined nature and large RV amplitude of ~15 km/s reveal itself. The discovery of this binary system is an important lesson for RV surveys searching for substellar companions; at a given resolution and observing cadence, a survey will be susceptible to these kinds of astrophysical false positives for a range of orbital parameters. Finally, for surveys like MARVELS that lack the resolution for a useful line bisector analysis, it is imperative to monitor the peak of the cross-correlation function for suspicious changes in width or shape, so that such false positives can be flagged during the candidate vetting process.Comment: 16 pages, 11 figures, 6 table

    Neuropsychological effects of chronic low-dose exposure to polychlorinated biphenyls (PCBs): A cross-sectional study

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    BACKGROUND: Exposure to indoor air of private or public buildings contaminated with polychlorinated biphenyls (PCBs) has raised health concerns in long-term users. This exploratory neuropsychological group study investigated the potential adverse effects of chronic low-dose exposure to specific air-borne low chlorinated PCBs on well-being and behavioral measures in adult humans. METHODS: Thirty employees exposed to indoor air contaminated with PCBs from elastic sealants in a school building were compared to 30 non-exposed controls matched for education and age, controlling for gender (age range 37–61 years). PCB exposure was verified by external exposure data and biological monitoring (PCB 28, 101, 138, 153, 180). Subjective complaints, learning and memory, executive function, and visual-spatial function was assessed by standardized neuropsychological testing. Since exposure status depended on the use of contaminated rooms, an objectively exposed subgroup (N = 16; PCB 28 = 0.20 μg/l; weighted exposure duration 17.9 ± 7 years) was identified and compared with 16 paired controls. RESULTS: Blood analyses indicated a moderate exposure effect size (d) relative to expected background exposure for total PCB (4.45 ± 2.44 μg/l; d = 0.4). A significant exposure effect was found for the low chlorinated PCBs 28 (0.28 ± 0.25 μg/l; d = 1.5) and 101 (0.07 ± 0.09 μg/l; d = 0.7). Although no neuropsychological effects exceeded the adjusted significance level, estimation statistics showed elevated effect sizes for several variables. The objectively exposed subgroup showed a trend towards increased subjective attentional and emotional complaints (tiredness and slowing of practical activities, emotional state) as well as attenuated attentional performance (response shifting and alertness in a cued reaction task). CONCLUSION: Chronic inhalation of low chlorinated PCBs that involved elevated blood levels was associated with a subtle attenuation of emotional well-being and attentional function. Extended research is needed to replicate the potential long-term low PCB effects in a larger sample
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