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Ecological rarity, characterized by low abundance or limited distribution, is typical of most species, yet our understanding of what factors contribute to the persistence of rare species remains limited. Consequently, little is also known about whether rare species might respond differently than common species to direct (e.g., abiotic) and indirect (e.g., biotic) effects of climate change. We investigated the effects of warming and exclusion of large herbivores on 14 tundra taxa, three of which were common and 11 of which were rare, at an inland, low-arctic study site near Kangerlussuaq, Greenland. Across all taxa, pooled commonness was reduced by experimental warming, and more strongly under herbivore exclusion than under herbivory. However, taxon-specific analyses revealed that although warming elicited variable effects on commonness, herbivore exclusion disproportionately reduced the commonness of rare taxa. Over the 15-year duration of the experiment, we also observed trends in commonness and rarity under all treatments through time. Sitewide commonness increased for two common taxa, the deciduous shrubs Betula nana and Salix glauca, and declined in six other taxa, all of which were rare. Rates of increase or decline in commonness (i.e., temporal trends over the duration of the experiment) were strongly related to baseline commonness of taxa early in the experiment under all treatments except warming with grazing. Hence, commonness itself may be a strong predictor of species' responses to climate change in the arctic tundra biome, but large herbivores may mediate such responses in rare taxa, perhaps facilitating their persistence.

The objective of this study was to determine the long-term water sorption, solubility and hygroscopic expansion of resin composites with and without incorporated short fibers. Three resin composites incorporating fibers were examined: everX Posterior (EVX), NovoPro Universal (NPU) and NovoPro Flow (NPF). Four Particulate filled composites were used as controls: Filtek bulk Fill (FBF), Filtek one bulkfill (FBO), Filtek Supreme XTE (XTE), and Filtek Supreme Flow (XTEF). For sorption and solubility measurements, specimens were immersed in water for140 days, weighed at intervals, then dried for a further 42 days at 37±1°C. Laser micrometer measured diametral expansion. XTEF exhibited the highest sorption. The solubility range was between -1.4 to 4.1 μg/mm; XTEF had the highest solubility, with EVX demonstrating negative solubility. Hygroscopic expansion ranged between 1.4% for hydroxyapatite fiber reinforced composite (NPU) and 2.2% for E-glass fiber reinforced composite (EVX). A nano-fiber containing composite (NPU) had the most favorable outcomes compared to a range of composites. [ABSTRACT FROM AUTHOR]

There is a common belief that eating patterns acquired during childhood shape them throughout adulthood. However, studies reveal that they can change. This paper explores this contradiction based on interviews with thirty-one people in Scotland. Viewing eating as a social practice, we adopt the lifecourse approach to demonstrate that there is evidence of both continuity and change in eating patterns over time. The concept of dys-appearance reveals why eating patterns are more likely to be revised and when these changes may be reflexively informed by dietary guidelines. This paper reveals that eating patterns acquired in childhood can shape them throughout the lifecourse and be resistant to attempts by others to change them. However, eating patterns may be more likely to change if the impetus for change originates within the individual and revisions are more likely to be informed by dietary guidelines when individuals view their eating patterns as problematic. Thus, this paper not only provides insight into the contradiction highlighted above, but also demonstrates the utility of viewing eating patterns as a social practice whilst illustrating the importance of individual agency in the reproduction of eating patterns, contributes to the sociology of the lifecourse and extends the application of dys-appearance. [ABSTRACT FROM AUTHOR]

Purpose: Habitual intense exercise may increase the incidence of upper respiratory symptoms (URS) in elite athletes. This study investigated whether immune gene expression could identify gene markers that discriminate athletes with a higher prevalence of URS. Methods: This cross-sectional analysis of elite Australian athletes from various sports investigated whether athletes retrospectively reporting URS for two days or more in a month (n=38), had an altered immune gene expression profile compared with asymptomatic athletes (n=33). Peripheral blood samples were collected during Olympic selection events with corresponding URS data collected for the one-month period before sampling. Digital immune gene expression analysis was undertaken using the NanoString PanCancer Immune Profiling panel. Results: Fifty immune genes were differentially expressed between the groups (p<0.05) and approximately 78% of these genes were more highly expressed in athletes reporting URS. Many of these genes were interferon-stimulated genes or genes involved in the Jak/Stat signalling pathway. Only interferon alpha inducible protein 27 (IFI27), an interferon stimulated gene involved in viral response, remained significantly higher in athletes reporting URS (log2 fold-difference=2.49, odds ratio 1.02 per unit increase; p<0.01) post-adjustment and discriminated athletes reporting URS from asymptomatic athletes with 78% accuracy. Conclusion: Expression of IFI27 could differentiate athletes reporting URS from asymptomatic athletes, a gene that is upregulated in the immune response to viral infection. Upregulation of viral signalling pathways provides novel information on the potential aetiology of URS in elite Olympic athletes. [ABSTRACT FROM AUTHOR]

The rationale leading to the present generation of resin composites is surveyed. There are many sub-classes such as flowable materials with specialized clinical indications. But a simplistic categorization of resin-composite materials is inappropriate. It is better to appreciate the factors that have driven recent developments. These include the search for low shrinkage composites and for greater depth of cure. Other necessary features are good handling behavior and sufficient strength for load-bearing situations. The esthetic challenge is for materials with superior and life-like optical properties and it is important to identify products that are good in every critical property. Nanotechnology has led to certain improvements, but the possibilities and limitations of nanoparticles must be appreciated. In all these developments, the structure and properties of the host tissues are a challenge and inspiration. Thus materials that can emulate the features of enamel and dentin are the goal of biomimetic design. [ABSTRACT FROM AUTHOR]