93 research outputs found

    Individual variation in the antisnake behavior of California ground squirrels (Spermophilus beecheyi)

    Get PDF
    California ground squirrels (Spermophilus beecheyi) have evolved behavioral defenses against their two predators, the northern Pacific rattlesnake (Crotalus viridis oreganus) and Pacific gopher snake (Pituophis melanoleucus catenifer). Two studies were used to examine individual variation in antisnake behavior as it might be affected by selection operating on arousability, fearfulness, and aggressiveness. In Study 1 the behavioral consistency of two litters of lab-reared juveniles was examined at two age periods during encounters with a caged gopher snake and domestic cat. Close-range investigation and tail flagging appeared to be governed by short-term motivational states that were not strongly correlated across age. Age correlations revealed that individual tendencies to throw substrate were relatively consistent for the snake and even more so for the cat. In Study 2, wild-caught adults were obtained from five sites where rattlesnakes and gopher snakes were abundant and from five sites where these snakes were rare or absent. Squirrels in a seminatural laboratory setting were given balanced presentations of a caged rattlesnake and gopher snake separated by 5 days. Snakes were recognized by all squirrels as potentially dangerous, irrespective of experience, age, and selective regime. Substrate throwing also was positively correlated for the two snakes in both groups of adults, indicating that level of aggressiveness is a consistent component of temperament not specific to species of snakes. Physiological arousal was not correlated strongly for the two snakes, but it was significantly lower in squirrels from sites where snakes were abundant. This suggests some specialization to reduce anxiety that possibly enhances tactical decision making

    Italian good practice recommendations on management of persons with Long-COVID

    Get PDF
    A significant number of people, following acute SARS-CoV-2 infection, report persistent symptoms or new symptoms that are sustained over time, often affecting different body systems. This condition, commonly referred to as Long-COVID, requires a complex clinical management. In Italy new health facilities specifically dedicated to the diagnosis and care of Long-COVID were implemented. However, the activity of these clinical centers is highly heterogeneous, with wide variation in the type of services provided, specialistic expertise and, ultimately, in the clinical care provided. Recommendations for a uniform management of Long-COVID were therefore needed. Professionals from different disciplines (including general practitioners, specialists in respiratory diseases, infectious diseases, internal medicine, geriatrics, cardiology, neurology, pediatrics, and odontostomatology) were invited to participate, together with a patient representative, in a multidisciplinary Panel appointed to draft Good Practices on clinical management of Long-COVID. The Panel, after extensive literature review, issued recommendations on 3 thematic areas: access to Long-COVID services, clinical evaluation, and organization of the services. The Panel highlighted the importance of providing integrated multidisciplinary care in the management of patients after SARS-CoV-2 infection, and agreed that a multidisciplinary service, one-stop clinic approach could avoid multiple referrals and reduce the number of appointments. In areas where multidisciplinary services are not available, services may be provided through integrated and coordinated primary, community, rehabilitation and mental health services. Management should be adapted according to the patient's needs and should promptly address possible life-threatening complications. The present recommendations could provide guidance and support in standardizing the care provided to Long-COVID patients

    Preventing Surge Snowball in Large-Scale Multi-Staged Natural Gas Compression Facilities

    No full text
    The study and the relevant dynamic simulations of a natural gas compressor train under surge conditions, which represent the major upset unsteady states, are presented and discussed. The study is aimed at improving the control scheme in order to prevent not only the arising of surge at the single compressor scale, but also the kind of snowball surge that propagates along the compressor train. The plant-wide control technique here proposed is functional to detect and adjust unsafe operating regimes for high-pressure compressors, which are energy-consuming items and for which, due to the required power, the lifecycle in-service costs may be comparable with the initial capital costs. An Acid Gas Injection (AGI) unit, which is operating in Middle East, is considered and a comparison of a dynamic simulation with and without plant-wide control improvements is proposed
    • …
    corecore