Maintaining ecosystem resilience: functional responses of tree cavity nesters to logging in temperate forests of the Americas

Logging often reduces taxonomic diversity in forest communities, but little is known about how this biodiversity loss affects the resilience of ecosystem functions. We examined how partial logging and clearcutting of temperate forests influenced functional diversity of birds that nest in tree cavities. We used point-counts in a before-after-control-impact design to examine the effects of logging on the value, range, and density of functional traits in bird communities in Canada (21 species) and Chile (16 species). Clearcutting, but not partial logging, reduced diversity in both systems. The effect was much more pronounced in Chile, where logging operations removed critical nesting resources (large decaying trees), than in Canada, where decaying aspen Populus tremuloides were retained on site. In Chile, logging was accompanied by declines in species richness, functional richness (amount of functional niche occupied by species), community-weighted body mass (average mass, weighted by species densities), and functional divergence (degree of maximization of divergence in occupied functional niche). In Canada, clearcutting did not affect species richness but nevertheless reduced functional richness and community-weighted body mass. Although some cavity-nesting birds can persist under intensive logging operations, their ecosystem functions may be severely compromised unless future nest trees can be retained on logged sites.Fil: Ibarra, José Tomás. University of British Columbia; Canadá. Pontificia Universidad Católica de Chile; ChileFil: Martin, Michaela. University of British Columbia; CanadáFil: Cockle, Kristina Louise. University of British Columbia; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Martin, Kathy. University of British Columbia; Canad

Prescription Opioid Fatalities: Examining Why the Healer Could be the Culprit

© 2018, Springer International Publishing AG, part of Springer Nature. Prescription opioid use has increased rapidly in developed countries, as have fatalities and other related adverse events. This review examines the intrinsic characteristics of opioids, including their mechanisms of action and pharmacokinetic and pharmacodynamic properties, to determine how the use of a regonised pharmacological remedy for a medically confirmed ailment could result in an accidental fatality. Opioids trigger biological processes that inhibit their own therapeutic effect. Prolonged use of opioids can result in activation of pronociceptive systems, leading to opioid-induced hyperalgesia and tolerance, while opioid metabolites can antagonise the antinociceptive action of the parent drug, also leading to opioid-induced hyperalgesia and tolerance. Pain stimulates respiration and counteracts the respiratory depression effect of opioids. Analgesia from opioids leads to loss of this protective mechanism, leading to increased risk of death due to respiratory failure. Increased patient counseling during opioid prescribing and dispensing, and limiting prescription to short-term use in non-malignant pain, may decrease the adverse effects of opioids. The vast majority of patients who unintentionally experience serious adverse events from pharmaceutical opioids do not start out as drug seekers. Even opioid use within prescribing guidelines can place some patients at risk of death and may prevent patients from seeking help for prescription opioid dependence