297 research outputs found

    Stratospheric constituent measurements using UV solar occultation technique

    Get PDF
    The photochemistry of the stratospheric ozone layer was studied as the result of predictions that trace amounts of pollutants can significantly affect the layer. One of the key species in the determination of the effects of these pollutants is the OH radical. A balloon flight was made to determine whether data on atmospheric OH could be obtained from lower resolution solar spectra obtained from high altitude during sunset

    Mining frequent itemsets a perspective from operations research

    Get PDF
    Many papers on frequent itemsets have been published. Besides some contests in this field were held. In the majority of the papers the focus is on speed. Ad hoc algorithms and datastructures were introduced. In this paper we put most of the algorithms in one framework, using classical Operations Research paradigms such as backtracking, depth-first and breadth-first search, and branch-and-bound. Moreover we present experimental results where the different algorithms are implemented under similar designs

    Soundscape Optimization in Nursing Homes Through Raising Awareness in Nursing Staff With MoSART+

    Get PDF
    Introduction: Soundscapes in nursing homes are often suboptimal for residents. This can cause them feeling anxious and unsafe, or develop behavioral and psychological problems. Residents with dementia cannot adapt nursing home environments to their needs due to cognitive and physical limitations. It is up to the staff of psycho-geriatric wards to improve the soundscape. We evaluated the effect of the sound awareness intervention Mobile Soundscape Appraisal and Recording Technology (MoSART+) on soundscapes in nursing homes. Methods: The MoSART+ intervention was carried out in four nursing homes and took three months in each home. The MoSART+ intervention involved training ambassadors, assessing the soundscape with the MoSART application by the nursing staff to raise their sound awareness on random time points, discussing the measurements, and implementing micro-interventions. Soundscapes were assessed from 0 to 100 on four attributes: pleasantness, eventfulness, complexity, and range of affordances. Based on these scores, soundscapes were classified in four dimensions: calm, lively, boring, and chaotic. Nursing staff graded the environment on a scale of 0 to 10. T-test and Z-tests were used to analyze data. Results: Staff recorded 1882 measurements with the MoSART app. "People," "music, TV, and radio," and "machines and appliances" were the most prevalent sound sources before and after the implementation of micro-interventions. Post-implementation of micro-interventions, soundscapes were pleasant (median 69.0; IQR 54.0-81.0), of low complexity (33.0; 18.0-47.0), uneventful (27.0; 14.0-46.5), and gave moderate affordances (50.0; 35.0-67.0). Changes in attributes were statistically significant (p < 0.01). The proportion of the dimension calm increased (z = 12.7, p < 0.01), the proportion of chaotic decreased (z = 15.0, p < 0.01), and the proportion of lively decreased not statically significant (z = 0.68, p = 0.79). The proportion of boring was unchanged. The proportion of grades ≥6 increased after implementation of the micro-interventions (z = 15.3, p < 0.01). The micro-interventions focused on removing or reducing disturbing sounds and were unique for each nursing home. Discussion: The MoSART+ intervention resulted in a statistically significantly improvement of soundscapes, and more favorable evaluations of the nursing staff. The intervention empowered staff to adapt soundscapes. Nursing homes can improve soundscapes by raising sound awareness among staff. Trial Registration: Netherlands National Trial Register (NL6831)

    Sounds in nursing homes and their effect on health in dementia:A systematic review

    Get PDF
    OBJECTIVES: Nursing home residents with dementia are sensitive to detrimental auditory environments. This paper presents the first literature review of empirical research investigating (1) the (perceived) intensity and sources of sounds in nursing homes, and (2) the influence of sounds on health of residents with dementia and staff. DESIGN: A systematic review was conducted in PubMed, Web of Science and Scopus. Study quality was assessed with the Mixed Methods Appraisal Tool. We used a narrative approach to present the results. RESULTS: We included 35 studies. Nine studies investigated sound intensity and reported high noise intensity with an average of 55-68 dB(A) (during daytime). In four studies about sound sources, human voices and electronic devices were the most dominant sources. Five cross-sectional studies focused on music interventions and reported positives effects on agitated behaviors. Four randomized controlled trials tested noise reduction as part of an intervention. In two studies, high-intensity sounds were associated with decreased nighttime sleep and increased agitation. The third study found an association between music and less agitation compared to other stimuli. The fourth study did not find an effect of noise on agitation. Two studies reported that a noisy environment had negative effects on staff. CONCLUSIONS: The need for appropriate auditory environments that are responsive to residents' cognitive abilities and functioning is not yet recognized widely. Future research needs to place greater emphasis on intervention-based and longitudinal study design

    Unraveling the Magnetic Signal of Individual Grains in a Hawaiian Lava Using Micromagnetic Tomography

    Get PDF
    Micromagnetic Tomography (MMT) is a new technique that allows the determination of magnetic moments of individual grains in volcanic rocks. Current MMT studies either showed that it is possible to obtain magnetic moments of relatively small numbers of grains in ideal sample material or provided important theoretical advances in MMT inversion theory and/or its statistical framework. Here, we present a large-scale application of MMT on a sample from the 1907-flow from Hawaii's Kilauea volcano producing magnetic moments of 1,646 grains. We produced 261,305 magnetic moments in total for these 1,646 grains, an increase of three orders of magnitude compared to earlier studies to assess the robustness of the MMT results, and a major step toward the number of grains that is necessary for paleomagnetic applications of MMT. Furthermore, we show that the recently proposed signal strength ratio is a powerful tool to scrutinize and select MMT results. Despite this progress, still only relatively large iron-oxide grains with diameters >1.5–2 μm can be reliably resolved, impeding a reliable paleomagnetic interpretation. To determine the magnetic moments of smaller (<1 μm) grains that may exhibit pseudo-single domain behavior and are therefore better paleomagnetic recorders, the resolution of the microcomputed tomography and magnetic scans necessary for MMT must be improved. Therefore, it is necessary to reduce the sample size in future MMT studies. Nevertheless, our study is an important step toward making MMT a useful paleomagnetic and rock-magnetic technique
    corecore