1,196 research outputs found

    Isaac Hall to Susan Kean, December 13, 1793

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    Isaac Hall to Susan Kean. A receipt for Susan Kean from a wholesale linen drapers merchant on Market Street in Philadelphia.https://digitalcommons.kean.edu/lhc_1790s/1500/thumbnail.jp

    Stress accumulation versus shape flattening in frustrated, warped-jigsaw particle assemblies

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    Geometrically frustrated assembly has emerged as an attractive paradigm for understanding and engineering assemblies with self-limiting, finite equilibrium dimensions. We propose and study a novel 2D particle based on a so-called "warped jigsaw" (WJ) shape design: directional bonds in a tapered particle favor curvature along multi-particle rows that frustrate 2D lattice order. We investigate how large-scale intra-assembly stress gradients emerge from the microscopic properties of the particles using a combination of numerical simulation and continuum elasticity. WJ particles can favor anisotropic ribbon assemblies, whose lateral width may be self-limiting depending on the relative strength of cohesive to elastic forces in the assembly, which we show to be controlled by the range of interactions and degree of shape misfit. The upper limits of self-limited size are controlled by the crossover between two elastic modes in assembly: the accumulation of shear with increasing width at small widths giving way to unbending of preferred row curvature, permitting assembly to grow to unlimited sizes. We show that the stiffness controlling distinct elastic modes is governed by combination and placement of repulsive and attractive binding regions, providing a means to extend the range of accumulating stress to sizes that are far in excess of the single particle size, which we corroborate via numerical studies of discrete particles of variable interactions. Lastly, we relate the ground-state energetics of the model to lower and upper limits on equilibrium assembly size control set by the fluctuations of width along the ribbon boundary.Comment: 18 pages, 9 figures, 2 appendice

    The urban garden : Port Alliance, Texas

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1990.Includes bibliographical references (p. 171-175).This thesis focuses on of three urban parks; Central Park i n New York , the Fens to Franklin Park in Boston, and Rock Creek Park in washington, designed by Frederick Law Olmsted and the growth of the cities around them. Imbedded in the histories of the parks and their cities are strategies for the development of a new town on the plains of north Texas around an airport named Alliance. A regional park system organized along the creek bottoms and flood plains surrounding Alliance can be a strong organizing element for growth in the last undeveloped quadrant of the Dallas-Fort Worth area. Not unlike the area around Alliance, Olmsted's parks were in the path of urban growth , yet each of the parks has been bounded by a diverse range of built response s from the cities that now surround them. This thesis examines the evolution of the urban edge where Olmsted's parks and their cities meet. The built domain that bounds the parks is called the Urban Garden. The Urban Garden i s a metaphorical set of ideas about how the urban edge of the city and the park interact. The variations in the Urban Gardens of New York, Boston, and Washington provide vivid examples of how cities build at the edge of urban parks. These variations of the urban edge suggest some possible futures for the parks and the city that will develop around Alliance.by Isaac Hall Manning.M.S

    Observation and properties of X(3872) at DO.

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    Abstract not available

    Predictors of Venous Thromboembolism in Patients with Advanced Common Solid Cancers

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    There is uncertainty about risk heterogeneity for venous thromboembolism (VTE) in older patients with advanced cancer and whether patients can be stratified according to VTE risk. We performed a retrospective cohort study of the linked Medicare-Surveillance, Epidemiology, and End Results cancer registry in older patients with advanced cancer of lung, breast, colon, prostate, or pancreas diagnosed between 1995–1999. We used survival analysis with demographics, comorbidities, and tumor characteristics/treatment as independent variables. Outcome was VTE diagnosed at least one month after cancer diagnosis. VTE rate was highest in the first year (3.4%). Compared to prostate cancer (1.4 VTEs/100 person-years), there was marked variability in VTE risk (hazard ratio (HR) for male-colon cancer 3.73 (95% CI 2.1–6.62), female-colon cancer HR 6.6 (3.83–11.38), up to female-pancreas cancer HR 21.57 (12.21–38.09). Stage IV cancer and chemotherapy resulted in higher risk (HRs 1.75 (1.44–2.12) and 1.31 (1.0–1.57), resp.). Stratifying the cohort by cancer type and stage using recursive partitioning analysis yielded five groups of VTE rates (nonlocalized prostate cancer 1.4 VTEs/100 person-years, to nonlocalized pancreatic cancer 17.4 VTEs/100 patient-years). In a high-risk population with advanced cancer, substantial variability in VTE risk exists, with notable differences according to cancer type and stage

    The Paleozoic Mount Carlton deposit, Bowen Basin, Northeast Australia: shallow high-sulfidation epithermal Au-Ag-Cu mineralization formed during rifting

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    Mount Carlton is a Paleozoic high-sulfidation epithermal deposit located in the northern segment of the Bowen Basin, northeast Queensland, Australia. The deposit is hosted in Early Permian volcanic and sedimentary rocks, and an open-pit mining operation includes the Au-rich V2 pit in the northeast and the Ag-rich A39 pit in the southwest. Mineralization at Mt. Carlton occurred during active rifting, partly contemporaneously with the deposition of volcanic sediments in localized half-graben and graben basins. Steep normal faults and fracture networks related to the rifting acted as fluid conduits and localized cores of silicic alteration. The silicic cores transition outward to zones of quartz-alunite alteration, which are, in turn, enveloped by a zone of quartz-dickite-kaolinite alteration. Epithermal mineralization at Mt. Carlton developed in three stages: Cu-Au-Ag mineralization dominated by enargite was overprinted by Zn-Pb-Au-Ag mineralization dominated by sphalerite, which, in turn, was overprinted by Cu-Au-Ag mineralization dominated by tennantite. Proximal Au-Cu mineralization in the V2 pit occurs in networks of steep faults associated with veins and hydrothermal breccias within a massive rhyodacite porphyry. Three distinct ore zones (Eastern, Western, and Link) are aligned, en echelon, along a broadly E trending corridor. The Western ore zone continues along ~600-m strike length to the southwest into the A39 pit, and it shows a metal zonation, from proximal to distal, of Au-Cu → Cu-Zn-Pb-Ag → Ag-Pb-(Cu) → Ag. Distal Ag mineralization in the A39 pit is concentrated in a volcanolacustrine sedimentary sequence that overlies the rhyodacite porphyry. It occurs in a stratabound position oriented parallel to primary sedimentary layering and locally exhibits synsedimentary ore textures. Such textures are interpreted to have formed as mineralizing fluids discharged into what most likely were lakes developed within localized rift basins, at the same time that the volcanolacustrine sediments were deposited. At depth, equivalent ore textures were produced within open spaces in the structural roots of the rift basins. 40Ar/39Ar dating of hydrothermal alunite yielded an age range of 284 ± 7 to 277 ± 7 Ma, which links the formation of the Mt. Carlton deposit to the Early Permian back-arc rifting stage in the Bowen Basin. Prolonged extension provided rapid burial of the deposit beneath a postmineralization, volcanosedimentary cover, which was essential for the exceptional preservation of Mt. Carlton. The same extension caused displacement of the rock pile along a series of shallowly dipping detachment faults and segmentation and rotation of the ore zones across steeply dipping normal faults. This deformation would have displaced any underlying porphyry mineralization relative to the current location of Mt. Carlton

    Open and Equitable Scholarly Communications: Creating a More Inclusive Future

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    For many years, the academic and research library workforce has worked to accelerate the transition to more open and equitable systems of scholarship. While significant progress has been made, barriers remain. The Association of College and Research Libraries (ACRL) seeks to stimulate further advances through this action- oriented research agenda, which is designed to provide practical, actionable information for academic librarians; include the perspectives of historically underrepresented communities in order to expand the profession’s understanding of research environments and scholarly communication systems; and point librarians and other scholars toward important research questions to investigate. This report represents a yearlong process of reviewing the scholarly and practice-based literature to take into account established investigation coupled with extensive public consultation to identify the major problems facing the academic library community. Through interviews, focus groups, workshops, and an online survey, over 1,000 members of the ACRL community offered their thoughts and expertise to shape this research agenda. Incorporating guidance and input from ACRL’s Research and Scholarly Environment Committee and an advisory panel, this document recommends ways to make the scholarly communications and research environment more open, inclusive, and equitable

    Examining the effects of the COVID-19 pandemic on community engagement for people with mobility disabilities

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    Background The COVID-19 pandemic and subsequent mandates upended community participation in the United States. People with disabilities were often more vulnerable to the adverse effects of the pandemic. Some areas of community participation affected for this population include employment, access to transportation, and social engagement and connection to others. Objectives The purpose of this study was to explore the effects of the COVID-19 pandemic for people with mobility disabilities across a variety of topics related to community engagement including social interactions with family and friends, and access to caregivers, groceries, transportation, and employment. Methods A survey was administered to participants with mobility disabilities (N = 39). Participants were asked to elaborate on topic areas that they identified as being affected by the COVID-19 pandemic. Data analysis included descriptive statistics and a content analysis in search of themes from open-ended responses. Results Results indicate that access to family and friends was the most negatively affected topic related to participation, followed by access to food and groceries, transportation, employment, living independently, caring for others, and participating in the community in general. In response to these pandemic-related challenges, participants reported utilizing technology to connect with others and to get essential items delivered. Conclusions Findings from this rapid research emphasize the need for emergency preparedness strategies, accessible and reliable resources related to technology use (e.g., Internet), and continued access to services for people with disabilities to maintain various aspects of community participation throughout the COVID-19 pandemic and in the future
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