2,204 research outputs found

    Optical Structural Health Monitoring Device

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    This non-destructive, optical fatigue detection and monitoring system relies on a small and unobtrusive light-scattering sensor that is installed on a component at the beginning of its life in order to periodically scan the component in situ. The method involves using a laser beam to scan the surface of the monitored component. The device scans a laser spot over a metal surface to which it is attached. As the laser beam scans the surface, disruptions in the surface cause increases in scattered light intensity. As the disruptions in the surface grow, they will cause the light to scatter more. Over time, the scattering intensities over the scanned line can be compared to detect changes in the metal surface to find cracks, crack precursors, or corrosion. This periodic monitoring of the surface can be used to indicate the degree of fatigue damage on a component and allow one to predict the remaining life and/or incipient mechanical failure of the monitored component. This wireless, compact device can operate for long periods under its own battery power and could one day use harvested power. The prototype device uses the popular open-source TinyOS operating system on an off-the-shelf Mica2 sensor mote, which allows wireless command and control through dynamically reconfigurable multi-node sensor networks. The small size and long life of this device could make it possible for the nodes to be installed and left in place over the course of years, and with wireless communication, data can be extracted from the nodes by operators without physical access to the devices. While a prototype has been demonstrated at the time of this reporting, further work is required in the system s development to take this technology into the field, especially to improve its power management and ruggedness. It should be possible to reduce the size and sensitivity as well. Establishment of better prognostic methods based on these data is also needed. The increase of surface roughness with fatigue is closely connected to the microstructure of the metal, and ongoing research is seeking to connect this observed evidence of the fatigue state with microstructural theories of fatigue evolution to allow more accurate prognosis of remaining component life. Plans are also being discussed for flight testing, perhaps on NASA s SOFIA platform

    Developing Age-Friendly Cities: An evidence-based evaluation tool

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    Recent years have seen a proliferation of initiatives aimed at enhancing the age-friendliness of urban settings. The World Health Organization's (WHO) global Age-Friendly Cities (AFC) programme has been central to these. Cities seeking to become more age-friendly need reliable ways of assessing their efforts. This article describes an evidence-based evaluation tool for age-friendly initiatives whose development was informed by fieldwork in Liverpool/UK. The tool complements existing assessment frameworks, including those provided by WHO, by paying particular attention to the structures and processes underlying age-friendly initiatives. It reflects the complexity of age-friendliness by reconciling a focus on breadth with detail and depth, and it allows for a highly accessible visual presentation of findings. Using selected examples from Liverpool, the article illustrates how the evaluation tool can be applied to guide policy and practice with an age-friendly focus in different urban contexts. Pilot testing in further settings is underway to refine the tool as a practical method for evaluation and for supporting city-level decision making. Key words: Age-Friendly City; evaluation tool; ageing; urbanisation; complex intervention

    Context-Specific Drinking and Social Anxiety: The Roles of Anticipatory Anxiety and Post-Event Processing

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    Individuals with clinically elevated social anxiety are especially vulnerable to alcohol-related problems, despite not drinking more than those with less anxiety. It is therefore important to identify contexts in which socially anxious persons drink more to inform intervention efforts. This study tested whether social anxiety was related to greater drinking before, during, or after a social event and whether such drinking was related to the psychosocial factors anticipatory anxiety or post-event processing (PEP; review of the social event). Among past-month drinkers, those with clinically elevated or higher social anxiety (HSA; n = 212) reported more anticipatory anxiety, more pre-event drinking to manage anxiety, and PEP than those with normative or lower social anxiety (LSA; n = 365). There was a significant indirect effect of social anxiety on pre-drinking via anticipatory anxiety. Social anxiety was related to more drinking during the event indirectly via the serial effects of anticipatory anxiety and pre-drinking. Unexpectedly, PEP did not mediate or moderate the relation between social anxiety and post-event drinking. In sum, anticipatory anxiety was related to more drinking before, during, and after a social event and HSA drinkers were especially vulnerable to drinking more to manage this anxiety, which increased drinking before and during the event. This effect was specific to anticipatory anxiety and not evident for another social anxiety-specific risk factor, PEP. Thus, anticipatory anxiety may be an important therapeutic target for drinkers generally and may be especially important among HSA drinkers

    Performance of Tall Fescue Varieties

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    The objective of the tall fescue breeding program is the development of varieties characterized by superior nutritive value (including reduced contents of perloline and loline alkaloids and the fungal endophyte, Epichloe typhina), palatability, disease resistance, and adaptation through the utilization of intergeneric and interspecific hybrid derivatives of ryegrass and tall fescue species. Varieties previously released from the breeding program were, Kentucky 31, Kenwell, and Kenhy. Johnstone tall fescue, developed cooperatively by the Kentucky Agricultural Experiment Station and USDA-ARS, was released March 1, 1982, as,a new variety. Johnstone is characterized as having low levels of perloline alkaloid and the fungal endophyte, Epichloe typhina, and improved forage quality during summer. It is expected that seed of Johnstone will be available commercially during 1984 or 1985

    Extended H? emission line sources from UWISH2

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    We present the extended source catalogue for the UKIRT Wide Field Infrared Survey for H2 (UWISH2). The survey is unbiased along the inner Galactic Plane from l ? 357° to l ? 65° and |b| ? 1.5° and covers 209 deg2. A further 42.0 and 35.5 deg2 of high dust column density regions have been targeted in Cygnus and Auriga. We have identified 33 200 individual extended H2 features. They have been classified to be associated with about 700 groups of jets and outflows, 284 individual (candidate) planetary nebulae, 30 supernova remnants and about 1300 photodissociation regions. We find a clear decline of star formation activity (traced by H2 emission from jets and photodissociation regions) with increasing distance from the Galactic Centre. About 60 per cent of the detected candidate planetary nebulae have no known counterpart and 25 per cent of all supernova remnants have detectable H2 emission associated with them

    Punctate vascular expression1 is a novel maize gene required for leaf pattern formation that functions downstream of the trans-acting small interfering RNA pathway

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    The maize (Zea mays) gene RAGGED SEEDLING2-R (RGD2-R) encodes an ARGONAUTE7-like protein required for the biogenesis of trans-acting small interfering RNA, which regulates the accumulation of AUXIN RESPONSE FACTOR3A transcripts in shoots. Although dorsiventral polarity is established in the narrow and cylindrical leaves of rgd2-R mutant plants, swapping of adaxial/abaxial epidermal identity occurs and suggests a model wherein RGD2 is required to coordinate dorsiventral and mediolateral patterning in maize leaves. Laser microdissection-microarray analyses of the rgd2-R mutant shoot apical meristem identified a novel gene, PUNCTATE VASCULAR EXPRESSION1 (PVE1), that is down-regulated in rgd2-R mutant apices. Transcripts of PVE1 provide an early molecular marker for vascular morphogenesis. Reverse genetic analyses suggest that PVE1 functions during vascular development and in mediolateral and dorsiventral patterning of maize leaves. Molecular genetic analyses of PVE1 and of rgd2-R;pve1-M2 double mutants suggest a model wherein PVE1 functions downstream of RGD2 in a pathway that intersects and interacts with the trans-acting small interfering RNA pathway

    Performance of Tall Fescue Varieties [1984]

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    The objective of the tall fescue breeding program is the development of varieties characterized by superior nutritive value (including reduced contents of perloline and loline alkaloids and the fungal endophyte, Epichloe typhina, (Acremonium coenophialum), palatability, disease resistance, and adaptation through the utilization of intergeneric and interspecific hybrid derivatives of ryegtass and tall fescue species. Varieties previously released from the breeding program were Kentucky 31, Kenwell; and Kenhy. Johnstone tall fescue, developed cooperatively by the Kentucky Agricultural Experiment Station and USDA-ARS, was released March 1, 1982, as a new variety. Johnstone is characterized as having low levels of perloline alkaloid and the fungal endophyte; Acremonium coenophialum, and improved forage quality during summer. It is expected that seed of Johnstone will be available commercially during 1985, and a good supply should be available for spring and summer 1986 planting

    Using a Modified \u3ci\u3eIn-Vitro\u3c/i\u3e Procedure to Measure Corn Bran Buoyancy

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    An in vitro procedure was modified to estimate rumen buoyancy of corn bran and fiber types. Inoculum was obtained from two beef heifers and mixed with McDougall’s buffer then distributed to the in vitro tubes for 30 hours incubation at 100 °F. Fibrous material formed a matte layer which was measured to describe buoyancy. Tubes contained 6g of a feedlot-type diet with 7.5% fiber type (alfalfa hay, grass hay, corn silage, or corn stalks), with no replacement or 25% replacement of the remaining corn with corn bran. Buoyancy declined over time. Alfalfa hay had the most positive effect on buoyancy of corn bran. This new method offers promise for describing rumen buoyancy

    Differential electrophysiological response during rest, self-referential, and non-self-referential tasks in human posteromedial cortex

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    The electrophysiological basis for higher brain activity during rest and internally directed cognition within the human default mode network (DMN) remains largely unknown. Here we use intracranial recordings in the human posteromedial cortex (PMC), a core node within the DMN, during conditions of cued rest, autobiographical judgments, and arithmetic processing. We found a heterogeneous profile of PMC responses in functional, spatial, and temporal domains. Although the majority of PMC sites showed increased broad gamma band activity (30-180 Hz) during rest, some PMC sites, proximal to the retrosplenial cortex, responded selectively to autobiographical stimuli. However, no site responded to both conditions, even though they were located within the boundaries of the DMN identified with resting-state functional imaging and similarly deactivated during arithmetic processing. These findings, which provide electrophysiological evidence for heterogeneity within the core of the DMN, will have important implications for neuroimaging studies of the DMN
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