Numerical prediction of saturation in dual scale fibrous reinforcements during Liquid Composite Molding

This paper presents a fractional flow model based on two-phase flow, resin and air, through a porous medium to simulate numerically Liquid Composites Molding (LCM) processes. It allows predicting the formation, transport and compression of voids in the modeling of LCM. The equations are derived by combining Darcy’s law and mass conservation for each phase (resin/air). In the model, the relative permeability and capillary pressure depend on saturation. The resin is incompressible and the air slightly compressible. Introducing some simplifications, the fractional flow model consists of a saturation equation coupled with a pressure/velocity equation including the effects of air solubility and compressibility. The introduction of air compressibility in the pressure equation allows for the numerical prediction of the experimental behavior at low constant resin injection flow rate. A good agreement was obtained between the numerical prediction of saturation in a glass fiber reinforcement and the experimental observations during the filling of a test mold by Resin Transfer Molding (RTM). 2015 Elsevier Ltd. All rights reserved.The authors acknowledge financial support of the Spanish Government (Project DPI2013-44903-R-AR).Gascón Martínez, ML.; García Manrique, JA.; Lebel, F.; Ruiz, E.; Trochu, F. (2015). Numerical prediction of saturation in dual scale fibrous reinforcements during Liquid Composite Molding. Composites Part A: Applied Science and Manufacturing. 77:275-284. https://doi.org/10.1016/j.compositesa.2015.05.019S2752847

New discoveries of Middle Paleolithic human remains from the “Bau de l'Aubésier (Vaucluse, France)”

Excavations in Middle Paleolithic levels at the “Bau de l’Aubésier (Vaucluse)” during 2000 yielded a maxillary molar and a partial mandible from late Middle Pleistocene levels, plus a maxillary molar from the early Late Pleistocene. The Middle Pleistocene remains (Aubesier 10 and 11) have close morphological affinities to contemporaneous European human remains, and the Neandertal molar (Aubesier 12) falls well within Neandertal ranges of variation. The teeth are notable for a toothpick groove on Aubesier 10 and the large dental caries in Aubesier 12. The Aubesier 11 mandible exhibits extensive pathological alterations of the alveolar process, indicating serious impairment of mastication.Des fouilles dans les niveaux du Paléolithique moyen du Bau de l’Aubésier (Vaucluse) en 2000 ont livré une molaire supérieure et une grande partie d’une mandibule des niveaux du Pléistocène moyen tardif ainsi qu’une molaire supérieure du début du Pléistocène supérieure. Les restes du Pléistocène moyen (Aubésier 10 et 11) ont des affinités morphologiques avec les autres restes humains contemporaines d’Europe, et la molaire néandertalienne (Aubésier 12) est bien dans la variation des Néandertaliens. Sur Aubésier 10 se remarque un sulcus de cure-dent, ainsi qu’une grande carie dentaire sur Aubésier 12. La mandibule Aubésier 11 montre des altérations pathologiques au niveaux des alvéoles, ce qui indique une mastication difficile

Observational Learning During Simulation-Based Training in Arthroscopy: Is It Useful to Novices?

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.OBJECTIVE: Observing experts constitutes an important and common learning experience for surgical residents before operating under direct guidance. However, studies suggest that exclusively observing experts may induce suboptimal motor learning, and watching errors from non-experts performing simple motor tasks may generate better performance. We investigated whether observational learning is transferrable to arthroscopy learning using virtual reality (VR) simulation. SETTING/DESIGN: In our surgical simulation laboratory, we compared students learning basic skills on a VR arthroscopy simulator after watching an expert video demonstration of VR arthroscopy tasks or a non-expert video demonstration of the same tasks to a Control group without video demonstration. Ninety students in 3 observing groups (expert, non-expert, and Control) subsequently completed the same procedure on a VR arthroscopy simulator. We hypothesized the non-expert-watching group would outperform the expert-watching group, and both groups to outperform the Control group. We examined performance pretest, posttest, and 1 week later. PARTICIPANTS: Participants were recruited from the final year of medical school and the very early first year of surgical residency training programs (orthopaedic surgery, urology, plastic surgery, and general surgery) at Western University (Ontario, Canada). RESULTS: All participants improved their overall performance from pretest to retention (p < 0.001). At initial retention testing, non-expert-watching group outperformed the other groups in camera path length p < 0.05 and time to completion, p < 0.05, and both the expert/non-expert groups surpassed the Control group in camera path length (p < 0.05). CONCLUSION: We suggest that error-observation may contribute to skills improvement in the non-expert-watching group. Allowing novices to observe techniques/errors of other novices may assist internalization of specific movements/skills required for effective motor performances. This study highlights the potential effect of observational learning on surgical skills acquisition and offers preliminary evidence for peer-based practice (combined non-experts and experts) as a complementary surgical motor skills training strategy.This project was supported by a Physicians׳ Services Incorporated (PSI) Foundation, Canada grant. Funds were used to pay for salary and employee benefits (LvE). The PSI Foundation did not play a role in the investigation

Managing Svalbard Tourism: Inconsistencies and Conflicts of Interest

The Svalbard Archipelago has experienced a rapid increase in tourism-related activities over the past few decades. The Norwegian Government’s ambition to develop the Archipelago’s tourism industry offers multiple socio-economic opportunities. The development and scope of these tourism activities is affected by a complex governance system that entails strict environmental regulation and preparedness considerations. To understand the balance of goals across the national and international policy levels, we have mapped, reviewed, and analyzed the national and international regulations and agreements that affect tourism activities on Svalbard. The document analysis reveals the framework of natural and environmental consideration, access to areas and passage, requirements for organized outdoor activities, and regulatory tools. We discovered conflicts and internal inconsistencies in the way that Svalbard tourism has developed. It has been shaped by both economic growth and environmental preservation, without any specific business development objectives and goals or acceptable limits of environmental and social change in place. For tourism stakeholders, this might complicate any rational assessment of the balance between economic development and environmental status. The challenges we have identified are specific to Svalbard, but are likely to be similar in many other Arctic locations involved in tourism

Six simple guidelines for introducing new genera of fungi

We formulate five guidelines for introducing new genera, plus one recommendation how to publish the results of scientific research. We recommend that reviewers and editors adhere to these guidelines. We propose that the underlying research is solid, and that the results and the final solutions are properly discussed. The six criteria are: (1) all genera that are recognized should be monophyletic; (2) the coverage of the phylogenetic tree should be wide in number of species, geographic coverage, and type species of the genera under study; (3) the branching of the phylogenetic trees has to have sufficient statistical support; (4) different options for the translation of the phylogenetic tree into a formal classification should be discussed and the final decision justified; (5) the phylogenetic evidence should be based on more than one gene; and (6) all supporting evidence and background information should be included in the publication in which the new taxa are proposed, and this publication should be peer-reviewed

Coproductive capacities: rethinking science-governance relations in a diverse world

Tackling major environmental change issues requires effective partnerships between science and governance, but relatively little work in this area has examined the diversity of settings from which such partnerships may, or may not, emerge. In this special feature we draw on experiences from around the world to demonstrate and investigate the consequences of diverse capacities and capabilities in bringing science and governance together. We propose the concept of coproductive capacities as a useful new lens through which to examine these relations. Coproductive capacity is “the combination of scientific resources and governance capability that shapes the extent to which a society, at various levels, can operationalize relationships between scientific and public, private, and civil society institutions and actors to effect scientifically-informed social change.” This recasts the relationships between science and society from notions of “gaps” to notions of interconnectedness and interplay (coproduction); alongside the societal foundations that shape what is or is not possible in that dynamic connection (capacities). The articles in this special feature apply this concept to reveal social, political, and institutional conditions that both support and inhibit high-quality environmental governance as global issues are tackled in particular places. Across these articles we suggest that five themes emerge as important to understanding coproductive capacity: history, experience, and perceptions; quality of relationships (especially in suboptimal settings); disjunct across scales; power, interests, and legitimacy; and alternative pathways for environmental governance. Taking a coproductive capacities perspective can help us identify which interventions may best enable scientifically informed, but locally sensitive approaches to environmental governance

Sequential generation of olfactory bulb glutamatergic neurons by Neurog2-expressing precursor cells

<p>Abstract</p> <p>Background</p> <p>While the diversity and spatio-temporal origin of olfactory bulb (OB) GABAergic interneurons has been studied in detail, much less is known about the subtypes of glutamatergic OB interneurons.</p> <p>Results</p> <p>We studied the temporal generation and diversity of Neurog2-positive precursor progeny using an inducible genetic fate mapping approach. We show that all subtypes of glutamatergic neurons derive from Neurog2 positive progenitors during development of the OB. Projection neurons, that is, mitral and tufted cells, are produced at early embryonic stages, while a heterogeneous population of glutamatergic juxtaglomerular neurons are generated at later embryonic as well as at perinatal stages. While most juxtaglomerular neurons express the T-Box protein Tbr2, those generated later also express Tbr1. Based on morphological features, these juxtaglomerular cells can be identified as tufted interneurons and short axon cells, respectively. Finally, targeted electroporation experiments provide evidence that while the majority of OB glutamatergic neurons are generated from intrabulbar progenitors, a small portion of them originate from extrabulbar regions at perinatal ages.</p> <p>Conclusions</p> <p>We provide the first comprehensive analysis of the temporal and spatial generation of OB glutamatergic neurons and identify distinct populations of juxtaglomerular interneurons that differ in their antigenic properties and time of origin.</p