Structured Deformations of Continua: Theory and Applications

The scope of this contribution is to present an overview of the theory of structured deformations of continua, together with some applications. Structured deformations aim at being a unified theory in which elastic and plastic behaviours, as well as fractures and defects can be described in a single setting. Since its introduction in the scientific community of rational mechanicists (Del Piero-Owen, ARMA 1993), the theory has been put in the framework of variational calculus (Choksi-Fonseca, ARMA 1997), thus allowing for solution of problems via energy minimization. Some background, three problems and a discussion on future directions are presented.Comment: 11 pages, 1 figure, 1 diagram. Submitted to the Proceedings volume of the conference CoMFoS1

Habitat Season, and Vocal Behaviour of Nocturnal Birds in a Neotropical Dry Forest

TITLE: Habitat, Season, and Vocal Behaviour of Nocturnal Birds in a Neotropical Dry Forest AUTHORS: Begin-Dyck HR, Owen K, Mennill DJ ABSTRACT: Earth is currently experiencing an alarming rate of global species extinction caused by several factors, most notably habitat loss. One habitat type that has faced considerable loss is Neotropical dry forest. These forests are threatened by multiple anthropogenic influences, including cattle ranching and climate change. To better understand the impacts of these threats on tropical dry forests, we can characterize the relationship between the behaviour of the species they contain and the condition of the habitat itself. Overall there has been a bias towards studying diurnal species, partly because visual detection is easier in the daytime. Therefore, nocturnal species are often overlooked. Bioacoustic approaches provide an effective way to study vocalizations of animals, especially for nocturnal animals that are difficult to detect under the cover of darkness. The goal of our investigation is to assess if the vocal behaviour of nocturnal birds in dry forest habitat is affected by seasonal variations and forest complexity using bioacoustic methods. Our study site, Sector Santa Rosa of the Guanacaste Conservation Area, is a mosaic of regenerating dry forest sites. Recordings were collected there using autonomous recording units during both dry and wet seasons. We annotated recordings from 20 dry forest sites, and identified species that vocalize between dusk and dawn at each site and for each season. Our preliminary findings suggest there is variation in the number of species that make nocturnal vocalizations, including some which are considered diurnal. Future research should focus on the reasons why these diurnal species are vocalizing at night. Our research will further our understanding of the vocal behaviour of nocturnal birds in tropical dry forest sites, one of Earth’s most endangered ecosystems. KEYWORDS: Bioacoustics, Tropical ecology, Dry forest, Nocturnal species, Avian researc

Advantages of Ion Mobility Coupled with HPLC/UPLC

Ion mobility is a new separation technique that can be coupled with high performance liquid chromatography (HPLC) or ultra-performance liquid chromatography (UPLC). Variances in cross-sectional ionic areas of different molecules create differential speeds through a gas allowing for millisecond separations. Combining ion mobility with both liquid chromatography and mass spectrometry with fragmentation, separations can be achieved on the second (HPLC), millisecond (ion mobility), and microsecond (mass spectrometry) timescales. This orthogonal separation greatly cleans up mass spectral data of co-eluting peaks from the liquid chromatography and adds to the descriptive data of each ion. With descriptive data such as retention time, cross-sectional area, m/z ratio, and mass spectral fragmentation, many options become available for analytical analysis. Options ranging from descriptive data collation into instrument libraries to sensitivity enhancement for trace analysis will be explored in this chapter along with the description of different forms of ion mobility

Comparison of four (11)C-labeled PET ligands to quantify translocator protein 18 kDa (TSPO) in human brain: (R)-PK11195, PBR28, DPA-713, and ER176-based on recent publications that measured specific-to-non-displaceable ratios.

Translocator protein (TSPO) is a biomarker for detecting neuroinflammation by PET. (11)C-(R)-PK11195 has been used to image TSPO since the 1980s. Here, we compared the utility of four (11)C-labeled ligands-(R)-PK11195, PBR28, DPA-713, and ER176-to quantify TSPO in healthy humans. For all of these ligands, BP ND (specific-to-non-displaceable ratio of distribution volumes) was measured by partially blocking specific binding with XNBD173 administration. In high-affinity binders, DPA-713 showed the highest BP ND of 7.3 followed by ER176 (4.2), PBR28 (1.2), and PK11195 (0.8). Only ER176 allows the inclusion of low-affinity binders because of little influence of radiometabolites and high BP ND. If inclusion of all three genotypes is important for study logistics, ER176 is the best of these four radioligands for studying neuroinflammation

A randomised feasibility study to investigate the impact of education and the addition of prompts on the sedentary behaviour of office workers

Abstract Background Office workers have been identified as being at risk of accumulating high amounts of sedentary time in prolonged events during work hours, which has been associated with increased risk of a number of long-term health conditions. There is some evidence that providing advice to stand at regular intervals during the working day, and using computer-based prompts, can reduce sedentary behaviour in office workers. However, evidence of effectiveness, feasibility and acceptability for these types of intervention is currently limited. Methods A 2-arm, parallel group, cluster-randomised feasibility trial to assess the acceptability of prompts to break up sedentary behaviour was conducted with office workers in a commercial bank (n = 21). Participants were assigned to an education only group (EG) or prompt and education group (PG). Both groups received education on reducing and breaking up sitting at work, and the PG also received hourly prompts, delivered by Microsoft Outlook over 10 weeks, reminding them to stand. Objective measurements of sedentary behaviour were made using activPAL monitors worn at three time points: baseline, in the last 2 weeks of the intervention period and 12 weeks after the intervention. Focus groups were conducted to explore the acceptability of the intervention and the motivations and barriers to changing sedentary behaviour. Results Randomly generated, customised prompts, delivered by Microsoft Outlook, with messages about breaking up sitting, proved to be a feasible and acceptable way of delivering prompts to office workers. Participants in both groups reduced their sitting, but changes were not maintained at follow-up. The education session seemed to increase outcome expectations of the benefits of changing sedentary behaviour and promote self-regulation of behaviour in some participants. However, low self-efficacy and a desire to conform to cultural norms were barriers to changing behaviour. Conclusions Prompts delivered by Microsoft Outlook were a feasible, low-cost way of prompting office workers to break up their sedentary behaviour, although further research is needed to determine whether this has an additional impact on sedentary behaviour, to education alone. The role of cultural norms, and promoting self-efficacy, should be considered in the design of future interventions. Trial registration This study was registered retrospectively as a clinical trial on ClinicalTrials.gov (ID no. NCT02609282 ) on 23 March 2015