CCL19-sorted mature dendritic cells have enhanced lymph node migratory capacity and function

No abstract available

A temperate former West Antarctic ice sheet suggested by an extensive zone of bed channels

Several recent studies predict that the West Antarctic Ice Sheet will become increasingly unstable under warmer conditions. Insights on such change can be assisted through investigations of the subglacial landscape, which contains imprints of former ice-sheet behavior. Here, we present radio-echo sounding data and satellite imagery revealing a series of ancient large sub-parallel subglacial bed channels preserved in the region between the Möller and Foundation Ice Streams, West Antarctica. We suggest that these newly recognized channels were formed by significant meltwater routed along the icesheet bed. The volume of water required is likely substantial and can most easily be explained by water generated at the ice surface. The Greenland Ice Sheet today exemplifies how significant seasonal surface melt can be transferred to the bed via englacial routing. For West Antarctica, the Pliocene (2.6–5.3 Ma) represents the most recent sustained period when temperatures could have been high enough to generate surface melt comparable to that of present-day Greenland. We propose, therefore, that a temperate ice sheet covered this location during Pliocene warm periods

Inland extent of the Weddell Sea Rift imaged by new aerogeophysical data

Peer reviewedPostprin

Resiliencia y metas académicas en estudiantes de secundaria de una institución pública de Trujillo

La investigación tuvo como objetivo principal establecer la relación que existe entre la resiliencia y las metas académicas en estudiantes de secundaria de una Institución Pública de Trujillo. El diseño de investigación fue no experimental, descriptivo correlacional; se trabajó con una muestra de 262 estudiantes de tercer, cuarto y quinto de secundaria de una Institución Pública de Trujillo. Los instrumentos que se utilizaron fueron: Escala de Resiliencia elaborado por Wagnild y Young, en la versión peruana elaborada por Novella en el año 2002 y adaptaba en Trujillo por Nunja en el año 2016, y el Cuestionario de Metas Académicas (C.M.A.) elaborado, por Hayamizu y Weiner en 1991, siendo traducida por Núñez y González en 1994, así también fue adaptada en la ciudad de Trujillo para esta investigación. Los resultados reflejaron que existe relación entre resiliencia y las metas académicas con una intensidad baja (Pearson= 253**; Spearman= 286**) a un 99% de significancia

Understanding the Interdependence of Penetration Depth and Deformation on Nanoindentation of Nanoporous Silver

International audienceA silver-based nanoporous material was produced by dealloying (selective chemical etching) of an Ag 38.75 Cu 38.75 Si 22.5 crystalline alloy. Composed of connected ligaments, this material was imaged using a scanning electron microscope (SEM) and focused ion-beam (FIB) scanning electron microscope tomography. Its mechanical behavior was evaluated using nanoindentation and found to be heterogeneous, with density variation over a length scale of a few tens of nanometers, similar to the indent size. This technique proved relevant to the investigation of a material's mechanical strength, as well as to how its behavior related to the material's microstructure. The hardness is recorded as a function of the indent depth and a phenomenological description based on strain gradient and densification kinetic was proposed to describe the resultant depth dependence

Antarctic ice sheet fertilises the Southern Ocean

Open access journalSouthern Ocean (SO) marine primary productivity (PP) is strongly influenced by the availability of iron in surface waters, which is thought to exert a significant control upon atmospheric CO2 concentrations on glacial/interglacial timescales. The zone bordering the Antarctic Ice Sheet exhibits high PP and seasonal plankton blooms in response to light and variations in iron availability. The sources of iron stimulating elevated SO PP are in debate. Established contributors include dust, coastal sediments/upwelling, icebergs and sea ice. Subglacial meltwater exported at the ice margin is a more recent suggestion, arising from intense iron cycling beneath the ice sheet. Icebergs and subglacial meltwater may supply a large amount of bioavailable iron to the SO, estimated in this study at 0.07-0.2 Tg yr-1. Here we apply the MIT global ocean model (Follows et al., 2007) to determine the potential impact of this level of iron export from the ice sheet upon SO PP. The export of iron from the ice sheet raises modelled SO PP by up to 40%, and provides one plausible explanation for seasonally very high in situ measurements of PP in the near-coastal zone. The impact on SO PP is greatest in coastal regions, which are also areas of high measured marine PP. These results suggest that the export of Antarctic runoff and icebergs may have an important impact on SO PP and should be included in future biogeochemical modelling.Philip Leverhulme PrizeLeverhulme Research FellowshipLeverhulme TrustRoyal Society Fellowship7th European Community Framework Programme - Marie Curie Intra European FellowshipNatural Environment Research Council (NERC

Diseño y desarrollo de un sistema portable de proximidad para invidentes que permite el uso de ambas manos

El presente trabajo de investigación tiene por objetivo diseñar y desarrollar un sistema portable de proximidad para invidentes que permite el uso de ambas manos, utilizando sensores de distancia por ultrasonido y un sistema de aviso por vibración, los cuales permiten a las personas invidentes alertar ante los obstáculos que existan en su desplazamiento. Adicionalmente, en este trabajo de investigación se muestra de forma general el modelamiento de las distintas variables asociadas a los elementos empleados en la construcción así mismo la implementación y construcción del prototipo como el desarrollo del hardware y software del prototipo. También se incluye simulaciones y pruebas de funcionamiento del sistema electrónico cuya implementación será un gorro visera, por última parte se tienen las conclusión y recomendaciones obtenidas tras el desarrollo del prototipo electrónico.Trabajo de investigaciónCampus Lima Centr

Sharing in the gig economy: from equitable work relations to exploitative HRM

PurposeThis paper aims to examine human resource management (HRM) in the gig economy through a moral economy lens and to uncover how sharing and firm ownership influences the (un)ethical use of HRM practices and worker treatment.Design/methodology/approachConceptual and empirical insights from contemporary HRM literature are synthesised through a systematic literature review to elucidate pressing challenges for research and practice.FindingsThe analysis reveals that the different ownership structures used by gig firms shape the nature and degree of sharing. The gig economy built on investor ownership leads to greater sharing with investors and tends to be more exploitative of workers, whereas platforms built on collaborative ownership engage in greater peer-to-peer sharing which is more equitable and leads to higher quality work relations and HRM.Practical implicationsThe closer an organisation's alignment with the more equitable/relational end of the gig economy spectrum, the better the work relations and HRM.Originality/valueA new integrated conceptual spectrum of sharing in the gig economy is advanced, which aids in understanding evolving developments in HRM theory and practice.</jats:sec