Recent ASDEX Upgrade research in support of ITER and DEMO

Recent experiments on the ASDEX Upgrade tokamak aim at improving the physics base for ITER and DEMO to aid the machine design and prepare efficient operation. Type I edge localized mode (ELM) mitigation using resonant magnetic perturbations (RMPs) has been shown at low pedestal collisionality ( ν ∗ ped < 0 . 4 ) . In contrast to the previous high ν ∗ regime, suppression only occurs in a narrow RMP spectral window, indicating a resonant process, and a concomitant confinement drop is observed due to a reduction of pedestal top density and electron temperature. Strong evidence is found for the ion heat flux to be the decisive element for the L–H power threshold. A physics based scaling of the density at which the minimum P LH occurs indicates that ITER could take advantage of it to initiate H-mode at lower density than that of the final Q = 10 operational point. Core density fluctuation measurements resolved in radius and wave number show that an increase of R/L T e introduced by off-axis electron cyclotron resonance heating (ECRH) mainly increases the large scale fluctuations. The radial variation of the fluctuation level is in agreement with simulations using the GENE code. Fast particles are shown to undergo classical slowing down in the absence of large scale magnetohydrodynamic (MHD) events and for low heating power, but show signs of anomalous radial redistribution at large heating power, consistent with a broadened off-axis neutral beam current drive current profile under these conditions. Neoclassical tearing mode (NTM) suppression experiments using electron cyclotron current drive (ECCD) with feedback controlled deposition have allowed to test several control strategies for ITER, including automated control of (3,2) and (2,1) NTMs during a single discharge. Disruption mitigation studies using massive gas injection (MGI) can show an increased fuelling efficiency with high field side injection, but a saturation of the fuelling efficiency is observed at high injected mass as needed for runaway electron suppression. Large locked modes can significantly decrease the fuelling efficiency and increase the asymmetry of radiated power during MGI mitigation. Concerning power exhaust, the partially detached ITER divertor scenario has been demonstrated at P sep /R = 10 MW m − 1 in ASDEX Upgrade, with a peak time averaged target load around 5MWm − 2 , well consistent with the component limits for ITER. Developing this towards DEMO, full detachment was achieved at P sep /R = 7MWm − 1 and stationary discharges with core radiation fraction of the order of DEMO requirements (70% instead of the 30% needed for ITER) were demonstrated. Finally, it remains difficult to establish the standard ITER Q = 10 scenario at low q 95 = 3 in the all-tungsten (all-W) ASDEX Upgrade due to the observed poor confinement at low β N . This is mainly due to a degraded pedestal performance and hence investigations at shifting the operational point to higher β N by lowering the current have been started. At higher q 95 , pedestal performance can be recovered by seeding N 2 as well as CD 4 , which is interpreted as improved pedestal stability due to the decrease of bootstrap current with increasing Z eff . Concerning advanced scenarios, the upgrade of ECRH power has allowed experiments with central ctr-ECCD to modify the q -profile in improved H-mode scenarios, showing an increase in confinement at still good MHD stability with flat elevated q -profiles at values between 1.5 and 2.European Commission (EUROfusion 633053

On the Extreme Positive Feedback Star-Forming Mode from Massive and Compact Superstar Clusters

The force of gravity acting within the volume occupied by young, compact and massive superstar clusters, is here shown to drive in situ all the matter deposited by winds and supernovae into several generations of star formation. These events are promoted by radiative cooling which drains the thermal energy of the ejected gas causing its accumulation to then rapidly exceed the gravitational instability criterion. A detailed account of the integrated ionizing radiation and mechanical luminosity as a function of time is here shown to lead to a new stationary solution. In this, the mass deposition rate $\dot M$, instead of causing a wind as in the adiabatic solution, turns into a positive feedback star-forming mode equal to the star formation rate. Some of the implications of this extreme positive feedback mode are discussed.Comment: 4 pages, 4 figures, accepted for publication in The Astrophysical Journal Letter

Overview of ASDEX Upgrade results

The ASDEX Upgrade (AUG) programme is directed towards physics input to critical elements of the ITER design and the preparation of ITER operation, as well as addressing physics issues for a future DEMO design. Since 2015, AUG is equipped with a new pair of 3-strap ICRF antennas, which were designed for a reduction of tungsten release during ICRF operation. As predicted, a factor two reduction on the ICRF-induced W plasma content could be achieved by the reduction of the sheath voltage at the antenna limiters via the compensation of the image currents of the central and side straps in the antenna frame. There are two main operational scenario lines in AUG. Experiments with low collisionality, which comprise current drive, ELM mitigation/suppression and fast ion physics, are mainly done with freshly boronized walls to reduce the tungsten influx at these high edge temperature conditions. Full ELM suppression and non-inductive operation up to a plasma current of Ip = 0.8 MA could be obtained at low plasma density. Plasma exhaust is studied under conditions of high neutral divertor pressure and separatrix electron density, where a fresh boronization is not required. Substantial progress could be achieved for the understanding of the confinement degradation by strong D puffing and the improvement with nitrogen or carbon seeding. Inward/outward shifts of the electron density profile relative to the temperature profile effect the edge stability via the pressure profile changes and lead to improved/decreased pedestal performance. Seeding and D gas puffing are found to effect the core fueling via changes in a region of high density on the high field side (HFSHD). The integration of all above mentioned operational scenarios will be feasible and naturally obtained in a large device where the edge is more opaque for neutrals and higher plasma temperatures provide a lower collisionality. The combination of exhaust control with pellet fueling has been successfully demonstrated. High divertor enrichment values of nitrogen EN 10 have been obtained during pellet injection, which is a prerequisite for the simultaneous achievement of good core plasma purity and high divertor radiation levels. Impurity accumulation observed in the all-metal AUG device caused by the strong neoclassical inward transport of tungsten in the pedestal is expected to be relieved by the higher neoclassical temperature screening in larger devices.European Commission (EUROfusion 633053

The impact of European Union austerity policy on women's work in Southern Europe

Contrary to consolidated economic theory principles, in Europe (but also in other world regions), austerity policy has been implemented instead of stimulus measures which have proven to be successful in crisis associated with credit crunch and insufficient demand. These policies cannot be only considered as an "austericide" due to ideological blindness. They also need to be considered as a strategy for imposing an economic and social reform which proved too difficult to be implemented in the years previous to the great recession. The ongoing fiscal contraction policies include the typical adjustment measures which are now driving the European economy towards a new type of insertion within the international economy. And as a consequence, they imply deep changes on the gender division of work deepening gender inequality. This article analyses the different effects of European Union austerity policy on women and men’s participation in the labour markets in two Southern European countries beaten by the Debt crisis: Spain and Italy. During the first part of this economics crisis, unemployment grew higher for men than for women, but in the second phase with the all sectors hit by the recession and the implementation of harsh austerity policies affecting public-sector jobs, women are also losing their jobs at the same rate than men. We have estimated labour supply models for individuals aged 25 to 54 living in couples with or without children by gender by using the EU-SILC 2011 micro data for Spain and Italy. The analysis carried out shows a strong countercyclical added-worker effect for women in response to transitory shocks in partner’s earnings, in contrast with a procyclical discouraged-worker effect for men. However though the added-worker effect prevails for women in Spain, in Italy still the discouraged worker effect dominates. The results show also a positive effect of the provision of childcare services on women’s labour supply. A cut in social and care services due to austerity promotion may turn the tendency to a decline in women’s participation and employment rates in the labour force with the subsequent loss of total well-being, due to gender differences in education performance, and especially of women’s well-being

1–42 b -Amyloid peptide requires PDK1/nPKC/Rac 1 pathway to induce neuronal death

1–42 b -Amyloid peptide requires PDK1/nPKC/Rac 1 pathway to induce neuronal death L Manterola 1,12 , M Hernando-Rodr ı ́ guez 2,12 , A Ruiz 3,4 , A Apraiz 5 , O Arrizabalaga 5 , L Vello ́ n 6 , E Alberdi 3,4 , F Cavaliere 3,4 , HM Lacerda 7 , S Jimenez 8,9 , LA Parada 10 , C Matute 3,4 and JL Zugaza 4,5,11 1–42 b -Amyloid (A b 1–42 ) peptide is a key molecule involved in the development of Alzheimer’s disease. Some of its effects are manifested at the neuronal morphological level. These morphological changes involve loss of neurites due to cytoskeleton alterations. However, the mechanism of A b 1–42 peptide activation of the neurodegenerative program is still poorly understood. Here, A b 1–42 peptide-induced transduction of cellular death signals through the phosphatidylinositol 3-kinase (PI3K)/ phosphoinositol-dependent kinase (PDK)/novel protein kinase C (nPKC)/Rac 1 axis is described. Furthermore, pharmacological inhibition of PDK1 and nPKC activities blocks Rac 1 activation and neuronal cell death. Our results provide insights into an unsuspected connection between PDK1, nPKCs and Rac 1 in the same signal-transduction pathway and points out nPKCs and Rac 1 as potential therapeutic targets to block the toxic effects of A b 1–42 peptide in neurons

Concentración de nutrientes en la escorrentía de diferentes predios del trópico enmendados con residuos animales bajo condiciones de lluvia natural.

Excessive nutrient losses from agricultural soils represent a major source of surface water contamination. In this study we quantified concentrations of total Kjeldahl nitrogen (TKN), dissolved and total phosphorus (DP,TP), and dissolved organic carbon (DOC) in runoff from two animal farm operations of Puerto Rico. The farms, one dairy and one poultry, represented typical conditions (i.e., topography, ecological zone, management system) of these production systems.Two fields were selected for the runoff studies on each farm, and two runoff collectors were installed in each field. Runoff samples were collected under natural rainfall conditions. The average phosphorus concentration in runoff from the poultry fields (5.87 mg TP/L, 4.82 mg DP/L) was significantly greater than that observed from the dairy fields (2.29 mg TP/L, 1.79 mg DP/L). Dissolved phosphorus concentrations represented more than 90% of the total P concentrations on both farms, a situation that may exacerbate the impact on receiving water bodies. Average DP concentrations exceeded 1 mg/L, a limit proposed for the regulation of runoff P concentrations from agricultural lands, in 70% of the runoff events at the dairy farm, and 100% of the events at the poultry farm. The magnitude of the nutrient concentrations on both farms was significantly affected by the time lapse between the manure applications and the first precipitation event. Nutrient concentrations in runoff samples were also significantly affected by rainfall depth.La pérdida excesiva de nutrientes de suelos agrícolas representa una fuente primaria de contaminación de los cuerpos de agua. En este estudio se cuantificaron las concentraciones de nitrógeno total Kjeldahl (NTK), fósforo total y disuelto (PD, PT), y carbón orgánico disuelto (COD) en la escorrentía de dos fincas productoras de animales de Puerto Rico. Las fincas, una vaquería y una avícola, son representativas de las condiciones típicas (i.e., topografía, zona ecológica, sistema de manejo) de estos sistemas de producción. En cada finca se seleccionaron dos predios para estudios de escorrentía y en cada predio se instalaron dos fraccionadores de escorrentía. Se recolectaron muestras de escorrentía generadas por eventos de lluvia natural. La concentración promedio de fósforo en la escorrentía de los predios avícolas (5.87 mg TP/L, 4.82 mg PD/L) fue significativamente mayor que la observada en los predios de la vaquería (2.29 mg PT/L, 1.79 mg PD/L). La concentración de PD representó cerca del 90% de la concentración de PT observada en ambas fincas, situación que puede agravar el impacto en las aguas circundantes. La concentración de PD promedio excedió 1 mg/L, límite propuesto para controlar la escorrentía de fósforo de predios agrícolas, en 70% de los eventos de escorrentía en el caso de la vaquería y en un 100% de los casos en la finca avícola. La magnitud de las concentraciones en ambas fincas se afectó significativamente por el lapso de tiempo transcurrido entre la aplicación de los residuos orgánicos y el primer evento de lluvia. La concentración de nutrientes en la escorrentía también se afectó significativamente con la profundidad de la lámina de lluvia

Endemic Species of the Family Poaceae in Chile: Taxonomy, Distribution, and Conservation

Due to its geographic isolation, Chile is a biogeographic island which harbors a high percentage of endemism. More than 50% of the native vascular flora is endemic and more than 60% lives in Central Chile, included in the Chilean Biodiversity Hotspot. Endemic are species with a geographic distribution restricted to a single area and could be especially vulnerable. For these reasons, updated lists of endemic species are necessary. Based on a databases, the study of specimens from two Chilean herbaria and the available literature, we present an updated list of grasses endemic to Chile indicating for each taxon the scientific accepted name, common names, type, life cycle, flowering period, distribution, conservation status, bibliographic references and representative specimen. Seventy-one species (19.9% of the native grass species) were classified as endemic. Most species occur along the Chilean hotspot of biodiversity, mainly in the Mediterranean region of the hotspot. One species (Podophorus bromoides) is extinct, three species are critically endangered, two species are endangered, one species is vulnerable, and one species is near threatened. The conservation status of most species (89%) needs to be evaluated. Most of the threatened species are endemic to the Juan Fernández Archipelago

Optical spectroscopy of the microquasar GRS 1758-258: a possible intermediate mass system?

Context. GRS 1758-258 is one of two prototypical microquasars towards the Galactic Center direction discovered almost a quarter of a century ago. The system remains poorly studied in the optical domain due to its counterpart being a very faint and absorbed target in a crowded region of the sky. Aims. Our aim is to investigate GRS 1758-258 in order to shed light on the nature of the stellar binary components. In particular, the main physical parameters of the donor star, such as the mass or the spectral type, are not yet well constrained. Methods. GRS 1758-258 has remained so far elusive to optical spectroscopy owing to its observational difficulties. Here, we use this traditional tool of stellar astronomy at low spectral resolution with a 10 m class telescope and a long slit spectrograph. Results. An improved spectrum is obtained as compared to previous work. The quality of the data does not allow the detection of emission or absorption features but, nevertheless, we manage to partially achieve our aims comparing the de-reddened continuum with the spectral energy distribution expected from an irradiated disc model and different donor star templates. Conclusions. We tentatively propose that GRS 1758-258 does not host a giant star companion. Instead, a main sequence star with mid-A spectral type appears to better agree with our data. The main impacts of this finding are the possibility that we are dealing with an intermediate mass system and, in this case, the prediction of an orbital period significantly shorter than previously proposed.Comment: 5 pages, 6 figures, accepted for publication in A&