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    New secondary batteries utilizing electronically conductive polymer cathodes

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    The objectives are to optimize the transport rates in electronically conductive polypyrrole films by controlling the morphology of the film and to assess the utility of these films as cathodes in a lithium/polypyrrole secondary battery. During this research period, a better understanding was gained of the fundamental electrochemical switching processes within the polypyrrole film. Three publications were submitted based on the work completed

    The systemic environment: at the interface of aging and adult neurogenesis.

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    Aging results in impaired neurogenesis in the two neurogenic niches of the adult mammalian brain, the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle. While significant work has characterized intrinsic cellular changes that contribute to this decline, it is increasingly apparent that the systemic environment also represents a critical driver of brain aging. Indeed, emerging studies utilizing the model of heterochronic parabiosis have revealed that immune-related molecular and cellular changes in the aging systemic environment negatively regulate adult neurogenesis. Interestingly, these studies have also demonstrated that age-related decline in neurogenesis can be ameliorated by exposure to the young systemic environment. While this burgeoning field of research is increasingly garnering interest, as yet, the precise mechanisms driving either the pro-aging effects of aged blood or the rejuvenating effects of young blood remain to be thoroughly defined. Here, we review how age-related changes in blood, blood-borne factors, and peripheral immune cells contribute to the age-related decline in adult neurogenesis in the mammalian brain, and posit both direct neural stem cell and indirect neurogenic niche-mediated mechanisms

    Designing an interactive multimedia instructional environment: the civil war interactive

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    This article describes the rationales behind the design decisions made in creating The Civil War Interactive, an interactive multimedia instructional product based on Ken Burns''s film series The Civil War

    Period derivative of the M15 X-ray Binary AC211/X2127+119

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    We have combined Rossi X-ray Timing Explorer observations of X2127+119, the low-mass X-ray binary in the globular cluster M15, with archival X-ray lightcurves to study the stability of the 17.1 hr orbital period. We find that the data cannot be fit by the Ilovaisky (1993) ephemeris, and requires either a 7sigma change to the period or a period derivative Pdot/P~9x10e-7 per year. Given its remarkably low L_X/L_opt such a Pdot lends support to models that require super-Eddington mass transfer in a q~1 binary.Comment: 11 pages, 3 figures, to be published in New Astronom

    The Greater Boston Housing Report Card 2015: The Housing Cost Conundrum

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    Why has housing supply not kept up with housing demand? This is the question we decided to finally tackle head-on in this edition of the "Greater Boston Housing Report Card" by undertaking an in-depth study of detailed housing cost data that we have collected from housing agencies and developers. The answer to our question is an unsettling one. We have failed to meet housing production targets because there is no way to do so given the high cost of producing housing for working and middle-income households. In part, this is because of the extreme barriers to new construction, especially in the form of severely restrictive zoning at the local level across much of Massachusetts.Solving this problem of insufficient housing supply will require a battery of new approaches to zoning and construction techniques -- something that has eluded developers and policymakers alike. We suggest in these pages some new approaches to increase housing supply

    The Formation of Brown Dwarfs: Observations

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    We review the current state of observational work on the formation of brown dwarfs, focusing on their initial mass function, velocity and spatial distributions at birth, multiplicity, accretion, and circumstellar disks. The available measurements of these various properties are consistent with a common formation mechanism for brown dwarfs and stars. In particular, the existence of widely separated binary brown dwarfs and a probable isolated proto-brown dwarf indicate that some substellar objects are able to form in the same manner as stars through unperturbed cloud fragmentation. Additional mechanisms such as ejection and photoevaporation may play a role in the birth of some brown dwarfs, but there is no observational evidence to date to suggest that they are the key elements that make it possible for substellar bodies to form.Comment: Protostars and Planets V, in pres
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