Potential field interpretation of the Baie Verte Peninsula, Newfoundland, utilizing constraints from Lithoprobe East Seismic line 89-13

An understanding of the geological setting of the Baic Verte Peninsula of Newfoundland is central to many interpretations of the Canadian Appalachians. In this paper we present an interpretation of the magnetic and gravity data for the area utilizing constraints from Lithoprobe Vibroscis line 89-13 which traverses the peninsula. The potential field data were processed using a number of techniques to provide shaded relief and other maps providing information on the depth of the sources. Density and magnetic susceptibility data were used in modelling the gravity and magnetic responses for two profiles, one the Lithoprobe line 89-13, and the other a profile farther north. The reflection seismic section was used to constrain the modelling. The Baie Verte Line is interpreted to be confined to the upper few kilometers of the crust. A prominent feature on the seismic section, and its corresponding step on the gravity and magnetic profiles, is interpreted to be the subsurface westward edge of a wedge of intact ophiolitic crust found on the eastern part of the peninsula. This feature is traced away from the seismic line by utilizing its potential field signature. The modelling and processing suggest that the potential field signatures can all be explained by sources in the upper 10 km of the crust, a conclusion consistent with earlier interpretations which were based on potential field data alone. RÉSUMÉ La compréhension du contexte géologique de la péninsule de Baie Verte de Terre-neuve est un élément crucial pour plusieurs interprétations des Appalaches canadiennes. Dans cet article, nous présentons une interprétation des données magnetiques et gravimetriques pour la région en utilisant des éléments provenant de la ligne de Vibroscis de Lithoprobe 89-13 qui traverse la péninsule. Les données du champ potentiel furent traitées en utilisant un certain nombre de techniques pour créer des reliefs ombragés et d'autres cartes fournissant de l'information sur la profondeur des sources. Les données de densité et de susceptibilité magnétique furent utilisés pour la modélisation des réponses gravimétriques et magnétiques pour deux sections, l'une étant la ligne Lithoprobe 89-13, et L'autre étant située plus au nord. La coupe de sismique réflexion fut utilisée pour priéiser le modéle. La ligne de Baie Verte est interpretée comme étant restreinle aux quelques kilomètres supérieurs de la croûte. Un dement important de la coupe sismique, et une variation y correspondent sur les profits gravimétriques et magnétiques, est interprété comme étant la marge occidental enfouie d'un biseau dc croute ophiolitique intacte qui se retrouve sur la partie est de la péninsule. Cet élément est suivi à distance du profit sismique en utilisant sa signature en champ potentiel. La modélisation et le traitement suggèrent que les signatures en champ potentiel peuvent toutes être expliquées par des sources dans les 10 km supérieurs de la croûte, une conclusion en accord avée les interprétations anteriéures qui étaient fondées uniquement sur les données du champ potentiel. [Traduit par la rédaction

A multi-disciplinary commentary on preclinical research to investigate vascular contributions to dementia

Although dementia research has been dominated by Alzheimer's disease (AD), most dementia in older people is now recognised to be due to mixed pathologies, usually combining vascular and AD brain pathology. Vascular cognitive impairment (VCI), which encompasses vascular dementia (VaD) is the second most common type of dementia. Models of VCI have been delayed by limited understanding of the underlying aetiology and pathogenesis. This review by a multidisciplinary, diverse (in terms of sex, geography and career stage), cross-institute team provides a perspective on limitations to current VCI models and recommendations for improving translation and reproducibility. We discuss reproducibility, clinical features of VCI and corresponding assessments in models, human pathology, bioinformatics approaches, and data sharing. We offer recommendations for future research, particularly focusing on small vessel disease as a main underpinning disorder

A Multi-disciplinary Commentary on Preclinical Research to investigate Vascular Contributions to Dementia

Although dementia research has been dominated by Alzheimer's disease (AD), most dementia in older people is now recognised to be due to mixed pathologies, usually combining vascular and AD brain pathology. Vascular cognitive impairment (VCI), which encompasses vascular dementia (VaD) is the second most common type of dementia. Models of VCI have been delayed by limited understanding of the underlying aetiology and pathogenesis. This review by a multidisciplinary, diverse (in terms of sex, geography and career stage), cross-institute team provides a perspective on limitations to current VCI models and recommendations for improving translation and reproducibility. We discuss reproducibility, clinical features of VCI and corresponding assessments in models, human pathology, bioinformatics approaches, and data sharing. We offer recommendations for future research, particularly focusing on small vessel disease as a main underpinning disorder.</p

The practice of 'doing' evaluation: Lessons learned from nine complex intervention trials in action

Background: There is increasing recognition among trialists of the challenges in understanding how particular 'real-life' contexts influence the delivery and receipt of complex health interventions. Evaluations of interventions to change health worker and/or patient behaviours in health service settings exemplify these challenges. When interpreting evaluation data, deviation from intended intervention implementation is accounted for through process evaluations of fidelity, reach, and intensity. However, no such systematic approach has been proposed to account for the way evaluation activities may deviate in practice from assumptions made when data are interpreted.Methods: A collective case study was conducted to explore experiences of undertaking evaluation activities in the real-life contexts of nine complex intervention trials seeking to improve appropriate diagnosis and treatment of malaria in varied health service settings. Multiple sources of data were used, including in-depth interviews with investigators, participant-observation of studies, and rounds of discussion and reflection.Results and discussion: From our experiences of the realities of conducting these evaluations, we identified six key 'lessons learned' about ways to become aware of and manage aspects of the fabric of trials involving the interface of researchers, fieldworkers, participants and data collection tools that may affect the intended production of data and interpretation of findings. These lessons included: foster a shared understanding across the study team of how individual practices contribute to the study goals; promote and facilitate within-team communications for ongoing reflection on the progress of the evaluation; establish processes for ongoing collaboration and dialogue between sub-study teams; the importance of a field research coordinator bridging everyday project management with scientific oversight; collect and review reflective field notes on the progress of the evaluation to aid interpretation of outcomes; and these approaches should help the identification of and reflection on possible overlaps between the evaluation and intervention.Conclusion: The lessons we have drawn point to the principle of reflexivity that, we argue, needs to become part of standard practice in the conduct of evaluations of complex interventions to promote more meaningful interpretations of the effects of an intervention and to better inform future implementation and decision-making. © 2014 Reynolds et al.; licensee BioMed Central Ltd

An avian survey conducted at five water sources within the northern Chihuahuan Desert on Indio Mountains Research Station, Texas

The objective of this study was to conduct an avian survey of five water sources (four ephemeral former cattle tanks and one perennial spring), determine how many species inhabit or use Indio Mountains Research Station, and show a hierarchal similarity between the survey sites. This survey was conducted in a Chihuahuan Desert scrub landscape on Indio Mountains Research Station (IMRS) in Hudspeth County, Texas. There have been no previous formal studies of the avifauna at IMRS. All species accounts or sightings have been from casual sightings. Eighty-five avian species were recorded during this project bringing the total of avian species observed on IMRS to 141 species. Rattlesnake Tank recorded the highest number of species with 60 and Squaw Spring the low with 47. Rattlesnake Tank and Mesquite Tank were the highest in similarity sharing 87% of their species. Squaw Spring was hypothesized to have had the highest number of species and be the outlier in similarity. This was rejected as it was grouped with Pirtle Tank in similarity and had the lowest number of species observed

Mechanics of elastomeric molecular composites

\u3cp\u3eA classic paradigm of soft and extensible polymer materials is the difficulty of combining reversible elasticity with high fracture toughness, in particular for moduli above 1 MPa. Our recent discovery of multiple network acrylic elastomers opened a pathway to obtain precisely such a combination. We show here that they can be seen as true molecular composites with a well–cross-linked network acting as a percolating filler embedded in an extensible matrix, so that the stress–strain curves of a family of molecular composite materials made with different volume fractions of the same cross-linked network can be renormalized into a master curve. For low volume fractions (&lt;3%) of cross-linked network, we demonstrate with mechanoluminescence experiments that the elastomer undergoes a strong localized softening due to scission of covalent bonds followed by a stable necking process, a phenomenon never observed before in elastomers. The quantification of the emitted luminescence shows that the damage in the material occurs in two steps, with a first step where random bond breakage occurs in the material accompanied by a moderate level of dissipated energy and a second step where a moderate level of more localized bond scission leads to a much larger level of dissipated energy. This combined use of mechanical macroscopic testing and molecular bond scission data provides unprecedented insight on how tough soft materials can damage and fail.\u3c/p\u3