Predicting the consequences of species loss using size-structured biodiversity approaches.

Understanding the consequences of species loss in complex ecological communities is one of the great challenges in current biodiversity research. For a long time, this topic has been addressed by traditional biodiversity experiments. Most of these approaches treat species as trait-free, taxonomic units characterizing communities only by species number without accounting for species traits. However, extinctions do not occur at random as there is a clear correlation between extinction risk and species traits. In this review, we assume that large species will be most threatened by extinction and use novel allometric and size-spectrum concepts that include body mass as a primary species trait at the levels of populations and individuals, respectively, to re-assess three classic debates on the relationships between biodiversity and (i) food-web structural complexity, (ii) community dynamic stability, and (iii) ecosystem functioning. Contrasting current expectations, size-structured approaches suggest that the loss of large species, that typically exploit most resource species, may lead to future food webs that are less interwoven and more structured by chains of interactions and compartments. The disruption of natural body-mass distributions maintaining food-web stability may trigger avalanches of secondary extinctions and strong trophic cascades with expected knock-on effects on the functionality of the ecosystems. Therefore, we argue that it is crucial to take into account body size as a species trait when analysing the consequences of biodiversity loss for natural ecosystems. Applying size-structured approaches provides an integrative ecological concept that enables a better understanding of each species' unique role across communities and the causes and consequences of biodiversity loss

Helminth fauna of the black-necked swan Cygnus melancoryphus (Aves: Anatidae) from Carlos Anwandter Nature Sanctuary, Valdivia, Chile

Parasitological studies in Anseriformes from Chile are scarce, with only 2 studies in the black-necked swan Cygnus melancoryphus Molina, 1792. Thus, the aim of the present survey was to contribute with new parasitic records for this swan. Necropsy was performed in the digestive tract of 46 C. melancoryphus collected at the Carlos Anwandter Nature Sanctuary. All examined birds were parasitized with at least 1 helminth species. The identified species were: Capillaria sp., Epomidiostomum vogelsangi Travassos, 1937, Hymenolepididae gen. sp., Catatropis verrucosa (Frolich, 1789) Odhner, 1905 and Echinostoma revolutum Frolich, 1802 sensu lato. Catatropis verrucosa and E. revolutum 5.1. are new records for C. melancoryphus as well as for the Chilean helminth fauna. The nematodes registered a higher prevalence regarding the other helminths, probably because they have direct life cycles, facilitating their transmission to swans. The isolated cestodes and trematodes require invertebrates, tadpoles or fishes as intermediate hosts. However, C. melancoryphus, being a strictly herbivorous bird, is likely to consume these items accidentally. Finally, additional studies are necessary to assess the impact of these parasites on the health of this threatened swan in Chile

Science readiness of the Gemini MCAO system: GeMS

The Gemini Multi-Conjugate Adaptive Optics System (GeMS) began its on-sky commissioning in January 2011. The system provides high order wide-field corrections using a constellation of five Laser Guide Stars. In December 2011, commissioning culminated in images with a FWHM of 80±2mas at 1.65 microns (H band) over an 87 x 87 arcsecond field of view. The first images have already demonstrated the scientific potential of GeMS, and after more than a year of commissioning GeMS is finally close to completion and ready for science. This paper presents a general status of the GeMS project and summarizes the achievements made during more than a year of commissioning. The characterization of GeMS performance is presented in a companion paper: "GeMS on-sky results", Rigaut et al.1 Here we report on the sub-systems' performance, discuss current limitations and present proposed upgrades. The integration of GeMS into the observatory operational scheme is detailed. Finally, we present the plans for next year's operations with GeMS

Efficacy and safety of parecoxib in the treatment of acute renal colic: a randomized clinical trial

PURPOSE: Although nonselective nonsteroidal anti-inflammatory drugs (nsNSAIDs) and opioids are effective treatments for acute renal colic, they are associated with adverse events (AEs). As cyclooxygenase-2 selective NSAIDs may provide a safer alternative, we compared the efficacy and safety of parecoxib versus an nsNSAID in subjects with acute renal colic. MATERIALS AND METHODS: Phase IV., multicenter, double-blind, noninferiority, active-controlled study: 338 subjects with acute renal colic were randomized to parecoxib 40 mg i.v. plus placebo (n = 174) or ketoprofen 100 mg IV plus placebo (n = 164). 338 subjects with acute renal colic were randomized to parecoxib 40 mg IV (n = 174) or ketoprofen 100 mg IV(n = 164) plus placebo. Subjects were evaluated 15, 30, 45, 60, 90 and 120 minutes after treatment start and 24 hours after discharge. Primary endpoint was the mean pain intensity difference (PID) at 30 minutes by visual analog scale (VAS) (per-protocol population). An ANCOVA model was used with treatment group, country, and baseline score as covariates. Non-inferiority of parecoxib to ketoprofen was declared if the lower bound of the 95% confidence interval (CI) for the difference between the two groups excluded the pre-established margin of 10 mm for the primary endpoint. RESULTS: Baseline demographics were similar. The mean (SD) mPID30 min was 33.84 (24.61) and 35.16 (26.01) for parecoxib and ketoprofen, respectively. For treatment difference (parecoxib-ketoprofen) the lower bound of the 95% CI was 6.53. The mean change from baseline in VAS 30 minutes after study medication was ~43 mm; AEs were comparable between treatments. CONCLUSIONS: Parecoxib is as effective as ketoprofen in the treatment of pain due to acute renal colic, is well tolerated, and has a comparable safety profile

Differential biodiversity responses between kingdoms (plants, fungi, bacteria and metazoa) along an Alpine succession gradient

Biological diversities of multiple kingdoms potentially respond in similar ways to environmental changes. However, studies either compare details of microbial diversity across general vegetation or land use classes or relate details of plant community diversity with the extent of microbially governed soil processes, via physiological profiling. Here, we test the hypothesis of shared responses of plant and rhizosphere bacterial, fungal and metazoan biodiversities (especially across-habitat \u3b2-diversity patterns) along a disturbance gradient encompassing grazed to abandoned Alpine pasture, on acid soil in the European Central Alps. Rhizosphere biological diversity was inferred from eDNA fractions specific to bacteria, fungi and metazoans from contrasting plant habitats indicative of different disturbance levels. We found that soil \u3b2-diversity patterns were weakly correlated with plant diversity measures and similarly ordinated along an evident edaphic (pH, C:N, assimilable P) and disturbance gradient but, contrary to our hypothesis, did not demonstrate the same diversity patterns. While plant communities were well separated along the disturbance gradient, correlating with fungal diversity, the majority of bacterial taxa were shared between disturbance levels (75% of bacteria were ubiquitous, cf. 29% plant species). Metazoa exhibited an intermediate response, with communities at the lowest levels of disturbance partially overlapping. Thus, plant and soil biological diversities were only loosely dependent and did not exhibit strictly linked environmental responses. This probably reflects the different spatial scales of organisms (and their habitats) and capacity to invest resources in persistent multicellular tissues, suggesting that vegetation responses to environmental change are unreliable indicators of below-ground biodiversity responses