299 research outputs found
Observational effects of magnetism in O stars: surface nitrogen abundances
We investigate the surface nitrogen content of the six magnetic O stars known
to date as well as of the early B-type star tau Sco. We compare these
abundances to predictions of evolutionary models to isolate the effects of
magnetic field on the transport of elements in stellar interiors. We conduct a
quantitative spectroscopic analysis of the sample stars with state-of-the-art
atmosphere models. We rely on high signal-to-noise ratio, high resolution
optical spectra obtained with ESPADONS at CFHT and NARVAL at TBL. Atmosphere
models and synthetic spectra are computed with the code CMFGEN. Values of N/H
together with their uncertainties are determined and compared to predictions of
evolutionary models. We find that the magnetic stars can be divided into two
groups: one with stars displaying no N enrichment (one object); and one with
stars most likely showing extra N enrichment (5 objects). For one star (Theta1
Ori C) no robust conclusion can be drawn due to its young age. The star with no
N enrichment is the one with the weakest magnetic field, possibly of dynamo
origin. It might be a star having experienced strong magnetic braking under the
condition of solid body rotation, but its rotational velocity is still
relatively large. The five stars with high N content were probably slow
rotators on the zero age main sequence, but they have surface N/H typical of
normal O stars, indicating that the presence of a (probably fossil) magnetic
field leads to extra enrichment. These stars may have a strong differential
rotation inducing shear mixing. Our results should be viewed as a basis on
which new theoretical simulations can rely to better understand the effect of
magnetism on the evolution of massive stars.Comment: 14 pages, 6 figures. Accepted by A&
Connection of Dynamic Quality Modeling and Total Service Management in Railway Transport Operation
Improving the quality of transport services should be based on the procedure leading to the formation of future better services and define processes to ensure quality so that they comply with the requirements of the customers. The technology of transport and carriage process is one of the elements of the transport system, the quality of which can be influenced actively through the use of new advanced technology. This paper is focused on the new approach in designing the preparation of processes and services in accordance with customer''s needs. New software solution was created for the achievement of the complexity of the preparation, effective implementation and timely indication of any diversions from quality in railway transport. The principles of the dynamic quality modeling and total service management were used as an important support for new software in railway transport operation
Analyzing and Decoding Natural Reach-and-Grasp Actions Using Gel, Water and Dry EEG Systems
Reaching and grasping is an essential part of everybody’s life, it allows meaningful interaction with the environment and is key to independent lifestyle. Recent electroencephalogram (EEG)-based studies have already shown that neural correlates of natural reach-and-grasp actions can be identified in the EEG. However, it is still in question whether these results obtained in a laboratory environment can make the transition to mobile applicable EEG systems for home use. In the current study, we investigated whether EEG-based correlates of natural reach-and-grasp actions can be successfully identified and decoded using mobile EEG systems, namely the water-based EEG-VersatileTM system and the dry-electrodes EEG-HeroTM headset. In addition, we also analyzed gel-based recordings obtained in a laboratory environment (g.USBamp/g.Ladybird, gold standard), which followed the same experimental parameters. For each recording system, 15 study participants performed 80 self-initiated reach-and-grasp actions toward a glass (palmar grasp) and a spoon (lateral grasp). Our results confirmed that EEG-based correlates of reach-and-grasp actions can be successfully identified using these mobile systems. In a single-trial multiclass-based decoding approach, which incorporated both movement conditions and rest, we could show that the low frequency time domain (LFTD) correlates were also decodable. Grand average peak accuracy calculated on unseen test data yielded for the water-based electrode system 62.3% (9.2% STD), whereas for the dry-electrodes headset reached 56.4% (8% STD). For the gel-based electrode system 61.3% (8.6% STD) could be achieved. To foster and promote further investigations in the field of EEG-based movement decoding, as well as to allow the interested community to make their own conclusions, we provide all datasets publicly available in the BNCI Horizon 2020 database (http://bnci-horizon-2020.eu/database/data-sets)
Urbanismo neoliberal y fragmentación urbana: El caso de Zaragoza (España) en los primeros quince años del siglo XXI
El crecimiento del espacio urbano de Zaragoza durante los primeros quince años del siglo xxi se caracteriza por su fragmentación socioespacial a varias escalas, un rasgo significativo del urbanismo neoliberal. En esta ciudad se ha seguido un modelo que se compone por grandes fragmentos monofuncionales, no separados unos de otros, sino soldados al espacio urbano preexistente por las principales arterias de circulación; estas vías y otros obstáculos físicos o percibidos interrumpen la continuidad con el espacio consolidado, sobre todo para el movimiento de personas. No obstante este patrón permite la conexión de los nuevos espacios con el entorno urbano local, al mismo tiempo fomenta la segregación social e impulsa un modelo policéntrico basado en desplazamientos en automóvil privado.
The growth of urban space of Zaragoza during the first fifteen years of the 21st century is characterized by its socio-spatial fragmentation at several scales, a significant feature of the neoliberal urbanism. The growth model of the city is composed of large monofunctional urban fragments attached to the existing urban space by the main traffic routes. These ways and other physical or perceived obstacles interrupt the continuity with the consolidated urban space, especially for the movement of people. Nevertheless, this pattern allows the connection of the new spaces with the local urban environment but, at the same time, promotes the social segregation and fosters a polycentric functional model based on travel by private car
Location of franchises and large retail chains following the Great Recession. The case of the city of Zaragoza (Spain)
The current retail activity model is rapidly evolving, in order to adapt to consumer changes. For a long time, shopping centres have stood out as the most attractive model. However, the implementation of franchises and large commercial chains in cities is transforming the uses of urban space and configuring new spatial relationships. The city of Saragossa serves as a case study
Moregrasp: Restoration of Upper Limb Function in Individuals with High Spinal Cord Injury by Multimodal Neuroprostheses for Interaction in Daily Activities
The aim of the MoreGrasp project is to develop a noninvasive, multimodal user interface including a brain-computer interface (BCI) for intuitive control of a grasp neuroprosthesis to support individuals with high spinal cord injury (SCI) in everyday activities. We describe the current state of the project, including the EEG system, preliminary results of natural movements decoding in people with SCI, the new electrode concept for the grasp neuroprosthesis, the shared control architecture behind the system and the implementation of a user-centered design
Psychometric properties of the Spanish Revised Short-Form of the Eysenck Personality Profiler – EPP-SFr
Compliant Substrates Enhance Macrophage Cytokine Release and NLRP3 Inflammasome Formation During Their Pro-Inflammatory Response
Immune cells process a myriad of biochemical signals but their function and behavior are also determined by mechanical cues. Macrophages are no exception to this. Being present in all types of tissues, macrophages are exposed to environments of varying stiffness, which can be further altered under pathological conditions. While it is becoming increasingly clear that macrophages are mechanosensitive, it remains poorly understood how mechanical cues modulate their inflammatory response. Here we report that substrate stiffness influences the expression of pro-inflammatory genes and the formation of the NLRP3 inflammasome, leading to changes in the secreted protein levels of the cytokines IL-1β and IL-6. Using polyacrylamide hydrogels of tunable elastic moduli between 0.2 and 33.1 kPa, we found that bone marrow-derived macrophages adopted a less spread and rounder morphology on compliant compared to stiff substrates. Upon LPS priming, the expression levels of the gene encoding for TNF-α were higher on more compliant hydrogels. When additionally stimulating macrophages with the ionophore nigericin, we observed an enhanced formation of the NLRP3 inflammasome, increased levels of cell death, and higher secreted protein levels of IL-1β and IL-6 on compliant substrates. The upregulation of inflammasome formation on compliant substrates was not primarily attributed to the decreased cell spreading, since spatially confining cells on micropatterns led to a reduction of inflammasome-positive cells compared to well-spread cells. Finally, interfering with actomyosin contractility diminished the differences in inflammasome formation between compliant and stiff substrates. In summary, we show that substrate stiffness modulates the pro-inflammatory response of macrophages, that the NLRP3 inflammasome is one of the components affected by macrophage mechanosensing, and a role for actomyosin contractility in this mechanosensory response. Thus, our results contribute to a better understanding of how microenvironment stiffness affects macrophage behavior, which might be relevant in diseases where tissue stiffness is altered and might potentially provide a basis for new strategies to modulate inflammatory responses
Concurrencia en torno a la planificación estratégica urbana. Análisis, aprendizajes y sinergias de la estrategia Zaragoza +20
Este trabajo analiza la Estrategia Zaragoza +20, marco de planificación estratégica que contiene las directrices para la intervención en la ciudad de Zaragoza (España) y su entorno metropolitano en los próximos años. En el contexto de la Planificación Estratégica Urbana, se describen los antecedentes y se revisa críticamente la metodología y enfoques empleados para la formulación del plan. La Estrategia se alinea con las principales agendas urbanas nacionales e internacionales, lo que supone uno de los primeros ejemplos en la planificación de las ciudades españolas..
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