3,775 research outputs found

    Origin Gaps and the Eternal Sunshine of the Second-Order Pendulum

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    The rich experiences of an intentional, goal-oriented life emerge, in an unpredictable fashion, from the basic laws of physics. Here I argue that this unpredictability is no mirage: there are true gaps between life and non-life, mind and mindlessness, and even between functional societies and groups of Hobbesian individuals. These gaps, I suggest, emerge from the mathematics of self-reference, and the logical barriers to prediction that self-referring systems present. Still, a mathematical truth does not imply a physical one: the universe need not have made self-reference possible. It did, and the question then is how. In the second half of this essay, I show how a basic move in physics, known as renormalization, transforms the "forgetful" second-order equations of fundamental physics into a rich, self-referential world that makes possible the major transitions we care so much about. While the universe runs in assembly code, the coarse-grained version runs in LISP, and it is from that the world of aim and intention grows.Comment: FQXI Prize Essay 2017. 18 pages, including afterword on Ostrogradsky's Theorem and an exchange with John Bova, Dresden Craig, and Paul Livingsto

    Meningeal carcinomatosis diagnosed during stroke evaluation in the emergency department

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    A 70-year-old female presented to the emergency department with a 3-day history of intermittent dysphasia and right facial droop. Computed tomography (CT) and magnetic resonance imaging (MRI) were obtained, and the patient was found to have meningeal carcinomatosis, also known as leptomeningeal metastases. Meningeal carcinomatosis is a rare metastatic complication of some solid tumors and hematopoietic neoplasms, and has a median survival rate of 2.4 months. The role of the emergency physician is to appropriately diagnose this condition, treat emergent side effects, provide symptomatic relief, and ensure multi-disciplinary management

    Comprehensive User Engagement Sites (CUES) in Philadelphia: A Constructive Proposal

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    This paper is a study about Philadelphia’s comprehensive user engagement sites (CUESs) as the authors address and examine issues related to the upcoming implementation of a CUES while seeking solutions for its disputed questions and plans. Beginning with the federal drug schedules, the authors visit some of the medical and public health issues vis-à-vis safe injection facilities (SIFs). Insite, a successful Canadian SIF, has been thoroughly researched as it represents a paradigm for which a Philadelphia CUES can expand upon. Also, the existing criticisms against SIFs are revisited while critically unpackaged and responded to in favor of the establishment. In the main section, the authors propose the layout and services of the upcoming CUES, much of which would be in congruent to Vancouver’s Insite. On the other hand, the CUES would be distinct from Insite, as the authors emphasize, in that it will offer an information center run by individuals in recovery and place additional emphasis on early education for young healthcare professionals by providing them a platform to work at the site. The paper will also briefly investigate the implementation of a CUES site under an ethical scope of the Harm Reduction Theory. Lastly, the authors recommend some strategic plans that the Philadelphia City government may consider employing at this crucial stage

    The impact of security bollards on evacuation flow

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    Individual bollard and bollard arrays (BA) have become a common design of Vehicle Security Barriers surrounding crowded spaces, in particular busy rail and underground stations, airports and many key commercial and public buildings. While guidance on the general installation of BA is available this earlier advice did not take into consideration the potential impact a BA may have on pedestrian flow during emergency evacuation. To address this issue, FSEG in collaboration with the CPNI and DfT investigated the potential impact that security bollards may have on evacuation flows through a series of full-scale experiments. In total 50 trials were conducted over three days on two weekends in March 2013. The experiment for each unique trial set up was repeated three times in order to ensure that the collected data was repeatable and representative of the trial conditions. The trials took place in the Queen Anne Courtyard of the University of Greenwich. Some 630 participants were recruited to take part in the trials, of which 458 actually participated. The trials were designed to capture the conditions produced as the population left a simulated station exit: at the point of exit (Exit flow trials) and when this population is incident upon the BA (BA flow trials). These trials were designed to control a number of key parameters in order to explore two specific questions: How does BA stand-off distance impact exit flow? And how does the BA impact flow passing through the BA? A key finding from these trials is that if the BA stand-off distance is greater than 3m there is not expected to be any adverse impact on exit flow due to the presence of the BA. However, it is essential that the BA is sufficiently wide so that it does not restrict the natural diffusion of the crowd as it exits

    Maternal obesity is associated with the formation of small dense LDL and hypoadiponectinemia in the third trimester

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    Context: Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL). Hypothesis: In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase. Design: Women (n = 55) of body mass index of 18–46 kg/m2 were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally. Setting: Women were recruited at hospital antenatal appointments, and study visits were in a clinical research suite. Outcome Measures: Plasma concentrations of lipids, triglyceride-rich lipoproteins, lipoprotein lipase mass, estradiol, steroid hormone binding globulin, insulin, glucose, leptin, and adiponectin were determined. Results: Obese women commenced pregnancy with higher plasma triglyceride, reached the same maximum, and then returned to higher postnatal levels than normal-weight women. Estradiol response to pregnancy (trimester 1–3 incremental area under the curve) was positively associated with plasma triglyceride response (r2 adjusted 25%, P < .001). In the third trimester, the proportion of small, dense LDL was 2-fold higher in obese women than normal-weight women [mean (SD) 40.7 (18.8) vs 21.9 (10.9)%, P = .014], and 35% of obese, 14% of overweight, and none of the normal-weight women displayed an atherogenic LDL subfraction phenotype. The small, dense LDL mass response to pregnancy was inversely associated with adiponectin response (17%, P = .013). Conclusions: Maternal obesity is associated with an atherogenic LDL subfraction phenotype and may provide a mechanistic link to poor vascular function and adverse pregnancy outcome

    The role of T helper type 17 cells in inflammatory arthritis

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    While T cells have been implicated in the pathogenesis of inflammatory arthritis for more than three decades, the focus on the T helper type 17 (Th17) subset of CD4 T cells and their secreted cytokines, such as interleukin (IL)-17, is much more recent. Proinflammatory actions of IL-17 were first identified in the 1990s, but the delineation of a distinct Th17 subset in late 2005 has sparked great interest in the role of these cells in a broad range of immune-mediated diseases. This review summarizes current understanding of the role of Th17 cells and their products in both animal models of inflammatory arthritis and human immune-driven arthritides.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75449/1/j.1365-2249.2009.04016.x.pd

    Disconnected Young People in New York City: Crisis and Opportunity

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    Commissioned by JobsFirstNYC, this report examines what is known about New York City's disconnected youth -- 16 to 24 year-olds who are not working and not in school. The report explores the roots of disconnection and identifies five priority populations of young people who are at high risk of becoming disconnected. It presents information about specific areas of the city with high concentrations of disconnected young people and summarizes a number of promising strategies for reclaiming this important human resource
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