9 research outputs found

    A hazai vasúti csendes folyosók várható hatása a zajterhelés alakulására

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    SURFACE LAYER’S SOUND SPEED PROFILES: CLIMATOLOGICAL ANALYSIS AND APPLICATION FOR THE CNOSSOS-EU NOISE MODEL

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    Noise pollution and exposure are important environmental issues that need to be investigated and regulated. To do this,we need to know about micrometeorology to figure out how noise travels from the source to the receiver. Accordingly, the sound propagation part of the common noise assessment methods (CNOSSOS-EU) developed by the European Commission for different sources of noise needs detailed meteorological databases. Using data from the SYNOP stations maintained by the Hungarian Meteorological Service (HMS) and the ERA5 meteorological reanalysis database, the standard noise propagation conditions are determined. The primary objective of this study is to ascertain the probability distribution of stability classes for a variety of source-receiver orientations, utilizing either 25 or 2 stability classes, and several different aggregation levels. Relative frequencies and year-to-year variability have been calculated for favourable noise propagation conditions where the sound speed profile grows with height (downward refraction condition) and unfavourable noise propagation conditions where the sound speed profile constant or decreases with height (so-called homogeneous conditions). Favourable noise propagation occurs in approximately one-third of cases during the daytime while in approximately two-third of cases during the evening and night-time where the noise exposure is increasing. Furthermore, using the SoundPLANnoise software, sound propagation model calculations were performed on a study area near Budapest, using different values of parameter pf describing the probability of occurrence of favourable conditions on sound propagation during different periods of the day. This area is crossed by Highway 4, which is a major road according to the 49/2002 EU Directive, as it has more than three million vehicles passing on the examined section every year. The results show considerable deviations in annual average A-weighted sound levels calculated using different versions of parameter pf. The largest difference between the A-weighted sound levels calculated with the highest and lowest generated annual pf values was 1.65 dB(A); 1.42 dB(A) and 0.75 dB(A) for day, evening and night periods, respectively.&nbsp

    A magyarországi akusztikai járműkategóriák megfeleltetése a CNOSSOS-EU módszer járműosztályainak

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    A közúti stratégiai zajtérképek előállítása során a hazai forgalomszámlálási gyakorlat nem teszi lehetővé a „szóló nehéz tehergépkocsi”, valamint a „motorkerékpár és segédmotoros kerékpár” forgalmi kategóriába tartozó járművek egyértelmű besorolását a CNOSSOS-EU módszer járműosztályaiba. Eltérő besorolási változatok zajkibocsátásra gyakorolt hatását elemezve előbbi kategóriára általánosan, utóbbira pedig a belterületi útszakaszokra vonatkozóan igazoltuk a probléma akusztikai relevanciáját

    Frontiers in pruritus research: scratching the brain for more effective itch therapy

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    This Review highlights selected frontiers in pruritus research and focuses on recently attained insights into the neurophysiological, neuroimmunological, and neuroendocrine mechanisms underlying skin-derived itch (pruritogenic pruritus), which may affect future antipruritic strategies. Special attention is paid to newly identified itch-specific neuronal pathways in the spinothalamic tract that are distinct from pain pathways and to CNS regions that process peripheral pruritogenic stimuli. In addition, the relation between itch and pain is discussed, with emphasis on how the intimate contacts between these closely related yet distinct sensory phenomena may be exploited therapeutically. Furthermore, newly identified or unduly neglected intracutaneous itch mediators (e.g., endovanilloids, proteases, cannabinoids, opioids, neurotrophins, and cytokines) and relevant receptors (e.g., vanilloid receptor channels and proteinase-activated, cannabinoid, opioid, cytokine, and new histamine receptors) are discussed. In summarizing promising new avenues for managing itch more effectively, we advocate therapeutic approaches that strive for the combination of peripherally active antiinflammatory agents with drugs that counteract chronic central itch sensitization

    Frontiers in pruritus research: scratching brain for more effective itch therapy

    No full text
    This Review highlights selected frontiers in pruritus research and focuses on recently attained insights into the neurophysiological, neuroimmunological, and neuroendocrine mechanisms underlying skin-derived itch (pruritogenic pruritus), which may affect future antipruritic strategies. Special attention is paid to newly identified itch-specific neuronal pathways in the spinothalamic tract that are distinct from pain pathways and to CNS regions that process peripheral pruritogenic stimuli. In addition, the relation between itch and pain is discussed, with emphasis on how the intimate contacts between these closely related yet distinct sensory phenomena may be exploited therapeutically. Furthermore, newly identified or unduly neglected intracutaneous itch mediators (e.g., endovanilloids, proteases, cannabinoids, opioids, neurotrophins, and cytokines) and relevant receptors (e.g., vanilloid receptor channels and proteinase-activated, cannabinoid, opioid, cytokine, and new histamine receptors) are discussed. In summarizing promising new avenues for managing itch more effectively, we advocate therapeutic approaches that strive for the combination of peripherally active antiinflammatory agents with drugs that counteract chronic central itch sensitization. The study of pruritus in a nutshell Itching (pruritus) is perhaps the most common symptom associated with numerous skin diseases and can be a lead symptom of extracutaneous disease (e.g., malignancy, infection, and metabolic disorders) (1, S1). However, despite approximately a century of pruritus research (2, S2, S3), there is no generally accepted therapy for the treatment of itch, and many mysteries, misconceptions, and controversies still haunt this rather neglected, yet clinically important and scientifically fascinating, niche in the life sciences (3, 4, 5). It is the brain that itches, not the skin Pruritus causes the desire to scratch the skin and is experienced as a sensation arising in the skin. However, like all other skin sensations, itch, strictly speaking, is an extracutaneous event - a product of CNS activities. The intense itch we feel after an insect bite, in a patch of atopic eczema, during an episode of food-induced urticaria, or in association with diabetes, uremia, or scabies mite infection (S1) represents a neuronal projection of a centrally formed sensation into defined regions of the integument (localized pruritus) or into large territories of our body surface (generalized pruritus). Interestingly, our individual reception of and emotional response to itch strongly depends on its exact quality: while a tickling sensation usually is experienced as pleasurable, persistent itch is an annoying or even torturous sensation (S4). While one is tempted to interpret this as indicating a distinct molecular and/or structural basis of these different itch qualities, it has proven excruciatingly difficult to identify their molecular, structural, and neurophysiological differences (ref. 1; see below). As pruritus can arise from localized or systemic, peripheral or central stimuli, it is useful to differentiate between its different types. One recent classification system suggests distinctions be made among neurogenic (arising from neurophysiological dysfunction, e.g., due to cholestasis or psychotropic medication), neuropathic (due to a primary neurological disorder), psychiatric (e.g., parasitophobia), and pruritogenic pruritus (arising from skin diseases) (3, 6). This Review discusses only the latter, most frequent type of pruritus, which requires the involvement and activity of cutaneous sensory neurons that transmit the "itchy" signals via dorsal root ganglia and the spinal cord to the CNS. Current concepts of itch pathways underlying pruritogenic pruritus and of CNS regions involved in itch processing are summarized in Scratching highlights the close relation of pain and itch Both pain and itch can be reduced by soft rubbing, which activates fast-conducting, low-threshold nerve fibers (7). However, the most characteristic response to itching is the scratch reflex: a more or less voluntary, often subconscious motoric activity to counteract the itch by slightly painful stimuli. This itch reduction is based on a spinal antagonism between pain- and itch-processing neurons (8). This illustrates a therapeutically exploitable, key concept in contemporary pruritus research: itch appears to be under tonic inhibitory control of pain-related signal
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