554 research outputs found

    Vulnerability Due to Nocturnal Tornadoes

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    This study investigates the human vulnerability caused by tornadoes that occurred between sunset and sunrise from 1880 to 2007. Nocturnal tornadoes are theorized to enhance vulnerability because they are difficult to spot and occur when the public tends to be asleep and in weak building structures. Results illustrate that the nocturnal tornado death rate over the past century has not shared the same pace of decline as those events transpiring during the daytime. From 1950 to 2005, a mere 27.3% of tornadoes were nocturnal, yet 39.3% of tornado fatalities and 42.1% of killer tornado events occurred at night. Tornadoes during the overnight period (local midnight to sunrise) are 2.5 times as likely to kill as those occurring during the daytime hours. It is argued that a core reason why the national tornado fatality toll has not continued to decrease in the past few decades is due to the vulnerability to these nocturnal events. This vulnerability is magnified when other factors such as escalating mobile (or “manufactured”) home stock and an increasing and spreading population are realized. Unlike other structure types that show no robust demarcation between nocturnal and daytime fatalities, nearly 61% of fatalities in mobile homes take place at night revealing this housing stock’s distinct nocturnal tornado vulnerability. Further, spatial analysis illustrates that the American South’s high nocturnal tornado risk is an important factor leading to the region’s high fatality rate. The investigation emphasizes a potential break in the tornado warning dissemination system utilized currently in the United States

    Using a Kinect Interface to Develop an Interactive 3D Tabletop Display

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    Since the release of the motion picture ’Minority Report’ in 2002, which depicts Tom Cruise interacting with a video display using only hand gestures, there has been a significant interest in the development of intelligent display technology, that users are able to interact with using gestures. In the real world it is common place for us to use gestures and body language to re-enforce our communication. It therefore becomes very natural for us to want to interact with our virtual media in the same way. Traditional methods for pose recognition involve using cameras to track the position of the user. However this can be very challenging to complete acurately in a variety of environments where camera can become occluded or the lighting conditions can change. In this research we prototyped a 3D tabletop display and explored the Kinect game controller as a possible solution to tracking the pose and gesture of a user whilst interacting with our display

    An examination of NMDA receptor contribution to conditioned responding evoked by the conditional stimulus effects of nicotine

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    Rationale—Research using a drug discriminated goal-tracking (DGT) task showed that the Nmethyl- D-aspartate (NMDA) channel blocker MK-801 (dizocilpine) reduced the nicotine-evoked conditioned response (CR). Objectives—Given the unknown mechanism of the effect, Experiment 1 replicated the MK-801 results and included tests with NMDA receptor ligands. Experiments 2a and 2b tested whether MK-801 pretreatment blocked DGT via a state-dependency effect. Methods—In Experiment 1, adult male Sprague–Dawley rats received intermittent access to liquid sucrose following nicotine (0.4 mg base/kg); no sucrose was delivered on intermixed saline sessions. Conditioning was indicated by increased anticipatory dipper entries (goal-tracking) on nicotine compared to saline sessions. Antagonism and/or substitution tests were conducted with MK-801, phencyclidine, CGP 39551, d-CPPene (SDZ EAA 494), Ro 25,6981, L-701,324, ACPC, and NMDA. In Experiment 2a, rats received nicotine and sucrose on every session—no intermixed saline sessions without sucrose. Tests combined MK-801 or the non-competitive nicotinic acetylcholine receptor antagonist, mecamylamine with either nicotine or saline. Experiment 2b had sucrose delivered on saline sessions and no sucrose on intermixed nicotine sessions followed by MK-801 antagonism tests of the saline CS. Results—MK-801 and phencyclidine dose-dependently attenuated the CR in Experiment 1. Ro-25,6981 enhanced the CR, but did not substitute for nicotine. Other ligands showed inconsistent effects. In Experiment 2a, MK-801 pretreatment reduced goal-tracking when given before nicotine and saline test sessions; mecamylamine pretreatment had no effect. In Experiment 2b, MK-801 dose-dependently attenuated the saline-evoked CR. Conclusions—Combined, the results suggest that MK-801 blocks discriminated goal-tracking by virtue of state-changing properties

    An examination of NMDA receptor contribution to conditioned responding evoked by the conditional stimulus effects of nicotine

    Get PDF
    Rationale—Research using a drug discriminated goal-tracking (DGT) task showed that the Nmethyl- D-aspartate (NMDA) channel blocker MK-801 (dizocilpine) reduced the nicotine-evoked conditioned response (CR). Objectives—Given the unknown mechanism of the effect, Experiment 1 replicated the MK-801 results and included tests with NMDA receptor ligands. Experiments 2a and 2b tested whether MK-801 pretreatment blocked DGT via a state-dependency effect. Methods—In Experiment 1, adult male Sprague–Dawley rats received intermittent access to liquid sucrose following nicotine (0.4 mg base/kg); no sucrose was delivered on intermixed saline sessions. Conditioning was indicated by increased anticipatory dipper entries (goal-tracking) on nicotine compared to saline sessions. Antagonism and/or substitution tests were conducted with MK-801, phencyclidine, CGP 39551, d-CPPene (SDZ EAA 494), Ro 25,6981, L-701,324, ACPC, and NMDA. In Experiment 2a, rats received nicotine and sucrose on every session—no intermixed saline sessions without sucrose. Tests combined MK-801 or the non-competitive nicotinic acetylcholine receptor antagonist, mecamylamine with either nicotine or saline. Experiment 2b had sucrose delivered on saline sessions and no sucrose on intermixed nicotine sessions followed by MK-801 antagonism tests of the saline CS. Results—MK-801 and phencyclidine dose-dependently attenuated the CR in Experiment 1. Ro-25,6981 enhanced the CR, but did not substitute for nicotine. Other ligands showed inconsistent effects. In Experiment 2a, MK-801 pretreatment reduced goal-tracking when given before nicotine and saline test sessions; mecamylamine pretreatment had no effect. In Experiment 2b, MK-801 dose-dependently attenuated the saline-evoked CR. Conclusions—Combined, the results suggest that MK-801 blocks discriminated goal-tracking by virtue of state-changing properties

    Low delta-T syndrome in cooling systems:A systematic review of the signs, symptoms, and causes

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    Return water temperature and flow rate are indicators of the energy efficiency of chilled water systems. Since the late 1980s, the return water temperature has deviated from the designed value, resulting in an increased flow rate. Such deviations have been recognized as a persistent ‘disease’ named low delta-T syndrome. Based on a medical approach, this study aimed to categorise the key signs and symptoms, and causes to classify low delta-T syndrome into subclasses with individual properties; to connect individual causes to the subclasses; and to identify disagreements on individual causes. Through a systematic review of the literature, over 190 papers published since the late 1980s were identified and studied. By combining different return water temperature profiles and flow rates, low delta-T syndrome was classified into four subclasses with severities ranging from 1 (mild) to 4 (extreme). These subclasses were described with 12 signs and symptoms, each characterised by 19 (from a total of 52) individual or combined causes, to provide an improved overview and a fundamental basis for developing treatments. A fundamental analysis of low delta-T syndrome on a cooling coil revealed that cooling coils with a high chilled water temperature difference and a high chilled water supply temperature at design conditions have a higher risk of developing it. This literature review provides an improved understanding of as well as considerations regarding how to prevent, resolve, mitigate, and handle low delta-T syndrome during design and operation
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