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Autoimmune inflammatory arthritides (AIA), such as psoriatic arthritis and rheumatoid arthritis, are chronic systemic conditions that affect multiple joints of the body. Recently, total-body (TB) PET/CT scanners exhibiting superior technical characteristics (total-body coverage, geometric sensitivity) that could benefit AIA evaluation, compared with conventional PET/CT systems, have become available. The objectives of this work were to assess the performance of an ultra-low-dose, 18F-FDG TB PET/CT acquisition protocol for evaluating systemic joint involvement in AIA and to report the association of TB PET/CT measures with joint-by-joint rheumatologic examination and standardized rheumatologic outcome measures. Methods: Thirty participants (24 with AIA and 6 with osteoarthritis) were prospectively enrolled in this single-center, observational study. All participants underwent a TB PET/CT scan for 20 min starting at 40 min after intravenous injection of 78.1 ± 4.7 MBq of 18F-FDG. Qualitative and quantitative evaluation of 18F-FDG uptake and joint involvement were performed from the resulting images and compared with the rheumatologic assessments. Results: TB PET/CT enabled the visualization of 18F-FDG uptake at joints of the entire body, including those of the hands and feet, in a single bed position, and in the same phase of radiotracer uptake. A range of pathologies consistent with AIA (and non-AIA in the osteoarthritis group) were visualized, and the feasibility of extracting PET measures from joints examined by rheumatologic assessments was demonstrated. Of 1,997 evaluable joints, there was concordance between TB PET qualitative assessments and joint-by-joint rheumatologic evaluation in the AIA and non-AIA cohorts for 69.9% and 91.1% joints, respectively, and an additional 20.1% and 8.8% joints, respectively, deemed negative on rheumatologic examination showed PET positivity. On the other hand, 10.0% and 0% joints in the AIA and non-AIA cohorts, respectively, were positive on rheumatologic evaluation but negative on TB PET. Quantitative measures from TB PET in the AIA cohort demonstrated a moderate-to-strong correlation (Spearman ρ = 0.53-0.70, P

The availability of suitable substrate for settlement can alter the behaviour of larvae of benthic marine invertebrates and consequently their settlement patterns. We tested the effect of the background substrate of a site (rocky vs sediment) on recruitment of invertebrates settling into standardized cobble-filled collectors deployed at shallow subtidal sites in the south-western Bay of Fundy, Canada, in 2009 and 2010. The assemblage of invertebrates that settled into the collectors differed significantly in both abundance and species composition between 'paired sites' ([almost equal to]0.003-0.009 km.sup.2 in area and 345-861 m apart) with rocky vs sediment background substrate, and markedly less so between paired sites comprised of rocky bottom. Species that are known to be rock-dwelling recruited in greater abundance to cobble-filled collectors at rocky sites, while those known to be sediment-dwelling recruited more to cobble-filled collectors at sediment sites. At the smaller spatial scale of patches of sediment within one site (14-107 m apart), differences in abundance but not species composition were detected between collectors on the two types of background substrate. This study supports the idea that larvae of some species of marine invertebrates respond to substrate at a larger spatial scale than their immediate location of settlement. Electronic supplementary material The online version of this article (doi:10.1007/s00227-015-2717-6) contains supplementary material, which is available to authorized users., Author(s): Lauren M. Ellis[sup.1] , Heather L. Hunt[sup.1] , Remy Rochette[sup.1] Author Affiliations: (1) Department of Biology, University of New Brunswick, PO Box 5050, E2L 4L5, Saint John, NB, Canada [...]

The authors examined the impact of pharmaceutical companies' advertisements on college students' perceptions of depression and concomitant treatment with antidepressants among 13 male and 31 female undergraduates from a midwestern university. The students were randomly assigned to groups that read either pharmaceutical company advertisements or scientific information about depression and its treatment. The analysis revealed that 40% of the women in the advertisement condition as opposed to 1 woman (6%) in the scientific condition rated themselves as having mild, moderate, or severe depression on the Beck Depression Inventory, second edition. Women in the advertisement condition were significantly more likely to believe that depression required treatment with antidepressant medication and were more willing than women in the scientific condition to suggest antidepressant treatment to others.

Research was conducted to examine the ion-molecule chemistry of boron trifluoride using electron impact ionization of molecular clusters. Time-of-flight mass spectrometry was used to analyze the resulting ion distribution. Results based on the ab initio modeling of the ions show that mass distribution is the result of reactions in and fragmentation of the clusters. Findings demonstrate that mass spectrometry is an efficient probe of ion-molecule chemistry within ionized clusters.

Predation is potentially an influential source of early post-settlement mortality of benthic marine invertebrates, but previous studies demonstrate conflicting results. We investigated the effect of large predators on developing subtidal invertebrate communities in cobble-filled collectors in the southwest Bay of Fundy, Canada. Two predation treatments (exclusion of predators ≥ 7 mm body width or full access for predators < 50 mm) were used to test the effect of large predators, and a partial-cage control tested for caging artefacts. Despite a reduction in the abundance and biomass of large predators, multivariate analyses indicated no effect of predator exclusion on the composition of the prey and micropredator communities. Results indicated that the largest differences were between the predator-access treatment and the other two treatments, which was potentially influenced by the caging material. There were significant but weak positive correlations between the micropredator and the other two communities. Previous studies indicate that at low predation intensity, as seemed to be the case here, other factors may play a stronger role in controlling recruit abundance. Predation control probably varies spatially and temporally, and the influence of large predators was not likely the driving force for early post-settlement mortality in the invertebrate communities measured in this study. [ABSTRACT FROM AUTHOR]

Soft-shell clams (Mya arenaria) can serve important ecological roles in intertidal mudflats and are an important economic and recreational resource in the northwestern Atlantic. However, environmental factors affecting newly-settled and juvenile clam abundances within a given settlement season remain uncertain. We conducted a field study assessing relationships between juvenile soft-shell clam abundance and spatial, temporal, and environmental variables in coastal mudflats of the northern shore of the Bay of Fundy. Sediment pH and low-tide water temperature (tide pools) were monitored in situ on a biweekly–monthly basis over the course of the M. arenaria settlement season in 2012 at four study sites to quantify diel variation in sediment pH and temperature. Core samples were also collected to quantify M. arenaria (<6 mm) abundance. Sea-surface and air temperature, and in situ sediment pH and water temperature were then used to predict clam abundance. Sediment pH was spatially and temporally variable, while in situ temperature was stable and declined over the sampling season. Akaike’s information criterion model selection indicated that models incorporating site, date, and air temperature best predicted 2012 recruitment patterns in linear models when all variables were included. When only environmental variables were included, the best linear model included minimum air temperature and sediment pH. When data were averaged across dates for each site to remove potential temporal effects, mean clam abundance displayed a significant positive relationship with sediment pH and sediment grain size, but not minimum air temperature. The results of this study suggest that sediment pH and/or sediment grain size may influence within-season juvenile soft-shell clam abundances across mudflats in the Bay of Fundy. Field experiments at the same (or similar) sites are now needed to confirm the mechanism driving the observed relationships. [ABSTRACT FROM AUTHOR]

While ocean acidification (OA) effects on marine organisms are well documented, impacts of sediment acidification on infaunal organisms are relatively understudied. Here we synthesize CO 2 -driven sediment acidification effects on infaunal marine bivalves. While sediment carbonate system conditions can already exceed near-future OA projections, sediments can become even more acidic as overlying seawater pH decreases. Evidence suggests that infaunal bivalves experience shell dissolution, more lesions, and increased mortality in more acidic sediments; effects on heavy metal accumulation appear complex and uncertain. Infaunal bivalves can avoid negative functional consequences of sediment acidification by reducing burrowing and increasing dispersal in more acidic sediments, irrespective of species or life stage; elevated temperature may compromise this avoidance behaviour. The combined effects of sediment acidification and other environmental stressors are virtually unknown. While it is evident that sediment acidification can impact infaunal marine bivalves, more research is needed to confidently predict effects under future ocean conditions. [ABSTRACT FROM AUTHOR]