695 research outputs found

    On the determination of near body orbits using mass concentration models

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    Mathematical model for near-body orbit calculation using mass concentration, perturbation theory, nonlinear equations, geopotentials, and least squares metho

    Magnitude, Trends, and Ecology of Juvenile Arrests in Tulsa, Oklahoma : a Longitudinal Study, 1970 Through 1989

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    I worked for two years as a volunteer juvenile counselor for the Comanche County Juvenile Bureau in Lawton, Oklahoma while attending Cameron University for my undergraduate degree. During that time I worked with teenage prostitutes, drug dealers, boys accused of rape, runaways, youths who just skipped school and many other youths. Each and every youth was different, but all were searching for something. I saw boys and girls who desperately wanted to be loved, and who were willing to go to any lengths to find it. The most difficult part for me was seeing these youngsters being hardened and turning cold towards the world around them and to life itself. Prior to this experience I assumed that juvenile delinquency was always something done by "bad" kids. I thought only the poor, abused and neglected would commit illegal acts. Children who had nothing were the ones who would steal, commit murder and harm the lives and property of others. I had the notion that most of our American society has; that is, the "bad people" are the source of the "bad behavior" in society. This view changed during the spring of 1987. I was setting around a campfire with those young adults who were there with me because of the things they had done. I was the counselor trying to help a group of youths sort out their lives, trying to help them find some meaning, some hope for the future, and some purpose for their lives right then. What happened was a change in me. Most of the youths there that night never came back through the Juvenile Bureau. Others we continued to see on a regular basis. But I realized for the first time that juvenile delinquency is much more than "bad kids committing crimes." What I saw in those young people was a reflection of myself; and I didn't consider my self a "bad person." I was no different. I committed some of the same crimes they did while I was growing up, but was not detected, apprehended, or became officially identified as a delinquent. From this interest I entered the graduate program in Sociology and selected as my thesis topic, "The Magnitude, Trends, and Ecology of Juvenile Arrests in Tulsa, Oklahoma." This study has been an attempt to investigate the magnitudes, trends, and ecology of Juvenile Delinquency in Tulsa, Oklahoma from 1970 through 1989. This project has examined the theoretical concept of high delinquency areas; it has identified clusters and patterns of juvenile arrests; and an analysis of the trends and magnitude of juvenile arrests has been done.Sociolog

    Appreciation of entertainment

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    The purpose of this article is to examine the experience of appreciation to media entertainment as a unique audience response that can be differentiated from enjoyment. To those ends, the first section provides a conceptualization of appreciation in which we outline how we are using the term and how it is distinct from questions of emotional valence. The second section discusses the types of entertainment portrayals and depictions that we believe are most likely to elicit feelings of appreciation. Here, we suggest that appreciation is most evident for meaningful portrayals that focus on human virtue and that inspire audiences to contemplate questions concerning life’s purpose. In the final section we consider the affective and cognitive components of appreciation, arguing that mixed-affective responses (rather than bi-polar conceptualizations of affective valence) better capture the experience of appreciation and its accompanying feelings states such as inspiration, awe, and tenderness

    The removal of thermally aged films of triacylglycerides by surfactant solutions

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    Thermal ageing of triacylglycerides (TAG) at high temperatures produces films which resist removal using aqueous surfactant solutions. We used a mass loss method to investigate the removal of thermally aged TAG films from hard surfaces using aqueous solutions of surfactants of different charge types. It was found that cationic surfactants are most effective at high pH, whereas anionics are most effective at low pH and a non-ionic surfactant is most effective at intermediate pH. We showed that the TAG film removal process occurs in several stages. In the first ‘‘lag phase’’ no TAG removal occurs; the surfactant first partitions into the thermally aged film. In the second stage, the TAG film containing surfactant was removed by solubilisation into micelles in the aqueous solution. The effects of pH and surfactant charge on the TAG removal process correlate with the effects of these variables on the extent of surfactant partitioning to the TAG film and on the maximum extent of TAG solubilisation within the micelles. Additionally, we showed how the TAG removal is enhanced by the addition of amphiphilic additives such as alcohols which act as co-surfactants. The study demonstrates that aqueous surfactant solutions provide a viable and more benign alternative to current methods for the removal of thermally aged TAG films

    Interactions of ingested food, beverage, and tobacco components involving human cytochrome P4501A2, 2A6, 2E1, and 3A4 enzymes.

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    Human cytochrome P450 (P450) enzymes are involved in the oxidation of natural products found in foods, beverages, and tobacco products and their catalytic activities can also be modulated by components of the materials. The microsomal activation of aflatoxin B1 to the exo-8,9-epoxide is stimulated by flavone and 7,8-benzoflavone, and attenuated by the flavonoid naringenin, a major component of grapefruit. P4502E1 has been demonstrated to play a potentially major role in the activation of a number of very low-molecular weight cancer suspects, including ethyl carbamate (urethan), which is present in alcoholic beverages and particularly stone brandies. The enzyme (P4502E1) is also known to be inducible by ethanol. Tobacco contains a large number of potential carcinogens. In human liver microsomes a significant role for P4501A2 can be demonstrated in the activation of cigarette smoke condensate. Some of the genotoxicity may be due to arylamines. P4501A2 is also inhibited by components of crude cigarette smoke condensate. The tobacco-specific nitrosamines are activated by a number of P450 enzymes. Of those known to be present in human liver, P4501A2, 2A6, and 2E1 can activate these nitrosamines to genotoxic products

    The z=0.54 LoBAL Quasar SDSS J085053.12+445122.5: II. The Nature of Partial Covering in the Broad-Absorption-Line Outflow

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    It has been known for 20 years that the absorbing gas in broad absorption line quasars does not completely cover the continuum emission region, and that partial covering must be accounted for to accurately measure the column density of the outflowing gas. However, the nature of partial covering itself is not understood. Extrapolation of the SimBAL spectral synthesis model of the HST COS UV spectrum from SDSS J0850+4451 reported by Leighly et al. 2018 to non-simultaneous rest-frame optical and near-infrared spectra reveals evidence that the covering fraction has wavelength dependence, and is a factor of 2.5 times higher in the UV than in the optical and near-infrared bands. The difference in covering fraction can be explained if the outflow consists of clumps that are small and either structured or clustered relative to the projected size of the UV continuum emission region, and have a more diffuse distribution on size scales comparable to the near-infrared continuum emission region size. The lower covering fraction over the larger physical area results in a reduction of the measured total column density by a factor of 1.6 compared with the UV-only solution. This experiment demonstrates that we can compare rest-frame UV and near-infrared absorption lines, specifically HeI*10830, to place constraints on the uniformity of absorption gas in broad absorbing line quasars.Comment: Revised version after responding to referee repor

    Orion Crew Exploration Vehicle Launch Abort System Guidance and Control Analysis Overview

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    Aborts during the critical ascent flight phase require the design and operation of Orion Crew Exploration Vehicle (CEV) systems to escape from the Crew Launch Vehicle (CLV) and return the crew safely to the Earth. To accomplish this requirement of continuous abort coverage, CEV ascent abort modes are being designed and analyzed to accommodate the velocity, altitude, atmospheric, and vehicle configuration changes that occur during ascent. Aborts from the launch pad to early in the flight of the CLV second stage are performed using the Launch Abort System (LAS). During this type of abort, the LAS Abort Motor is used to pull the Crew Module (CM) safely away from the CLV and Service Module (SM). LAS abort guidance and control studies and design trades are being conducted so that more informed decisions can be made regarding the vehicle abort requirements, design, and operation. This paper presents an overview of the Orion CEV, an overview of the LAS ascent abort mode, and a summary of key LAS abort analysis methods and results

    Inspiration on Social Media: Applying an Entertainment Perspective to Longitudinally Explore Mental Health and Well-Being

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    The conditions under which social media use impacts well-being and mental health are complex. The current 10-day longitudinal quasi-experiment (student sample, N = 111) applied an entertainment theory lens to explore the effects of active posting and engaging with hedonic or inspiring Facebook content (vs. passive browsing) on young people’s eudaimonic well-being (levels of connectedness to humanity, love, compassion, presence of meaning) and mental health (anxiety and depressive symptoms). The results provide tentative evidence that finding and sharing inspiring content to a Facebook group increased love and compassion toward others over time. It also led to more compassion at the end of the study compared to participants who shared hedonic content. Although we did not find an increase in connectedness and meaningfulness over time for participants sharing content that they found inspiring, the latter also did not take away from those experiences, regardless of how they used it. Similarly, no decrease—but also no increase—in anxiety and depressive symptoms were found over time, regardless of condition. The study stresses the importance of better understanding the content young adults engage with on social media for their mental health and well-being

    Road Network Simulation Using FLAME GPU

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    Demand for high performance road network simulation is increasing due to the need for improved traffic management to cope with the globally increasing number of road vehicles and the poor capacity utilisation of existing infrastructure. This paper demonstrates FLAME GPU as a suitable Agent Based Simulation environment for road network simulations, capable of coping with the increasing demands on road network simulation. Gipps’ car following model is implemented and used to demonstrate the performance of simulation as the problem size is scaled. The performance of message communication techniques has been evaluated to give insight into the impact of runtime generated data structures to improve agent communication performance. A custom visualisation is demonstrated for FLAME GPU simulations and the techniques used are described
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