3,201 research outputs found

    American Pie: The Politics of Food in the 21st Century

    Get PDF
    American Pie: The Politics of Food in the 21st Century In light of the increasing interest in food studies at Penn and in Philadelphia, Penn Libraries is sponsoring the Muriel Pfaelzer Bodek Public Affairs Lecture Series focusing on food policy in the 21st century. The speakers, experts in their fields, address issues relating to global food security, sustainable agriculture, and food waste in America. Wednesday, April 11, 2012: Jonathan Bloom, The Food Not Eaten : Jonathan Bloom, journalist and author of American Wasteland: How America Throws Away Nearly Half of Its Food (and What We Can Do About It) (2010), speaks on how much food we waste, where and why we squander so much, the ethical, environmental, and economic impact of our actions, and, most importantly, how we can minimize waste. Thursday, April 19, 2012: Alan M. Kelly, Global Food Security: A 21st Century Challenge Dr. Alan M. Kelly, Dean Emeritus and Professor of Veterinary Medicine, University of Pennsylvania, speaks on the challenges faced by agriculture as it expands production to meet society\u27s growing needs while conserving the environment, controlling the spread of infectious diseases, and accommodating to the vagaries of climate change. Tuesday, April 24, 2012: John E. Ikerd, The Future of Food: Sustainable Agriculture is not Optional Dr. John E. Ikerd, Professor Emeritus of Agricultural Economics, University of Missouri, and author of Sustainable Capitalism: A Matter of Common Sense and Small Farms are Real Farms: Sustaining People Through Agriculture, will speak on the need for sustainable agriculture, the challenges facing the movement, and the development of a new and better paradigm. To download podcasts of these lectures, choose one of the additional files below. Lectures by Jonathan Bloom and Alan Kelly are available for download in audio-only (.mp3) and as audio with image (.m4v) versions. To view the event announcement, select Download button at upper right

    OPTIC: Orbiting Plutonian Topographic Image Craft Proposal for an Unmanned Mission to Pluto

    Get PDF
    The proposal for an unmanned probe to Pluto is presented and described. The Orbiting Plutonian Topographic Image Craft's (OPTIC's) trip will take twenty years and after its arrival, will begin its data collection which includes image and radar mapping, surface spectral analysis, and magnetospheric studies. This probe's design was developed based on the request for proposal of an unmanned probe to Pluto requirements. The distinct problems which an orbiter causes for each subsystem of the craft are discussed. The final design revolved around two important factors: (1) the ability to collect and return the maximum quantity of information on the Plutonian system; and (2) the weight limitations which the choice of an orbiting craft implied. The velocity requirements of this type of mission severely limited the weight available for mission execution-owing to the large portion of overall weight required as fuel to fly the craft with present technology. The topics covered include: (1) scientific instrumentation; (2) mission management; (3) power and propulsion; (4) attitude and articulation control; (5) structural subsystems; and (6) command, control, and communication

    OCEANIC FLUXES FROM PROGLACIAL AND DEGLACIAL WATERSHEDS IN WESTERN GREENLAND

    Get PDF
    Weathering in western Greenland occurs in two distinct environments: proglacial watersheds that extend from the margin of the Greenland Ice Sheet (GIS) and derive water from ice melt, and deglacial watersheds that develop on terrains unconnected to the GIS and derive water from annual precipitation. Proglacial and deglacial watersheds currently provide equal amounts of runoff in western Greenland. These watersheds may contribute different solute fluxes to the oceans depending on exposure age, climate, and weathering environment. We test this hypothesis by comparing chemical compositions of streams in four deglacial watersheds (Sisimiut, Nerumaq, Qorlortoq, Kangerlussuaq) and one proglacial watershed (Watson River Akuliarusiarsuup Kuua River; AKR) along a ~160 km transect from the coast to the GIS. Recent work found that weathering reactions in the deglacial watersheds shift from being dominated by carbonate dissolution inland to sulfide oxidation near the coast. Silicate weathering, based on increased Si, Na and K concentrations, is a minor source of solutes to deglacial streams and is less extensive near the GIS than the coast, where older moraines experience greater precipitation. In general, specific conductivity (SpC: 48-301 μS/cm) and pH (7.0-8.2) increase inland as precipitation decreases and fresh mineral surfaces become more common. The AKR, in contrast, has lower average SpC (11.9 uS/cm) and pH (6.86) than the deglacial streams. Low SpC reflects dilution by ice melt and short residence time of water in the subglacial system. Proglacial flow is enriched in Si compared to deglacial flow particularly near headwaters, indicating higher silicate weathering rates in the pro- and sub-glacial systems. Low pH values indicate: 1) equilibration with atmospheric CO2 in the supraglacial system near headwaters, and 2) acid production generated by sulfide oxidation in the hyporheic zone identified by elevated SO4 concentrations. However, Ca, Mg and HCO3 are the dominant ions over the length of the AKR indicating that dissolution of carbonate is the predominant form of weathering. Our results indicate the two types of watersheds provide distinct fluxes of solutes to the oceans that are likely to change as ice sheets retreat and advance with changing climate

    Caucasian Infants’ Attentional Orienting to Own- and Other-Race Faces

    Get PDF
    Infants show preferential attention toward faces and detect faces embedded within complex naturalistic scenes. Newborn infants are insensitive to race, but rapidly develop differential processing of own- and other-race faces. In the present study, we investigated the development of attentional orienting toward own- and other-race faces embedded within naturalistic scenes. Infants aged six-, nine- and twelve-months did not show differences in the speed of orienting to own- and other race faces, but other-race faces held infants’ visual attention for longer. We also found a clear developmental progression in attentional capture and holding, with older infants orienting to faces faster and fixating them for longer. Results are interpreted within the context of the two-process model of face processing

    Hydrologic exchange and chemical weathering in a proglacial watershed near Kangerlussuaq, west Greenland

    Get PDF
    The exchange of proglacial river water with active layer pore water could alter water chemical compositions in glacial outwash plains and oceanic solute fluxes. To evaluate effects of this exchange, we sampled Watson River and adjacent pore water during the 2013 melt season at two sandurs in western Greenland; one in Sandflugtdalen and the other near the confluence with Søndre Strømfjord. We measured temperature, specific conductivity, and head gradients between the river and bank over a week-long period at Sandflugtdalen, as well as sediment hydraulic conductivity and chemical compositions of waters from both sites. Specific conductivity of pore water is four to ten times greater than river water as solutes are concentrated from weathering reactions, cryoconcentration, and evaporation. Pore water compositions are predominantly altered by carbonate dissolution and sulfide mineral oxidation. High concentrations of HCO3 and SO4 result from solute recycling and dissolution of secondary Ca-Mg carbonate/sulfate salts initially formed by near-surface evaporation in the summer and at depth by freeze-in of the active layer and cryoconcentration in the winter. High hydraulic conductivity (10−5 to 10−4 m/s) and diurnal fluctuations of river stage during our study caused exchange of river and pore water immediately adjacent to the river channel, with a net loss of river water to the bank. Pore water \u3e6 m from the river continuously flowed away from the river. Approximately 1–8% of the river discharge through the Sandflugtdalen was lost to the river bank during our 6.75 day study based on calculations using Darcy’s Law. Although not sampled, some of this water should discharge to the river during low river stage early and late in the melt season. Elevated pore water solute concentrations in sandurs and water exchange at diurnal and seasonal frequency should impact fluxes of solutes to the ocean, although understanding the magnitude of this effect will require long-term evaluation throughout the melt season

    The ecology of peer review: Person-centred, strength-based, and self-determination perspectives

    Get PDF
    The peer-review system, commonly considered critical for research integrity and rigour, has been criticised for being slow, exclusionary and exploitive. Concerns include the high profits of academic publishers as well as the growing number of insecurely employed academic staff who report high levels of stress and burnout. The consequence has been a decline in willing reviewers, publication delays, and potential damage to the career trajectories of early career researchers and PhD candidates at institutions that rely on metrics of academic impact as measures of academic performance. Rather than overhaul the system and undermine current benefits, this critical review adopts an ecological lens to posit an approach that is humanistic, transparent, and above all things, kind. This approach frames an applied perspective on how to improve peer-review moving forward
    • …
    corecore