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We have investigated the case of a coronal mass ejection that was eroded by the fast wind of a coronal hole in the interplanetary medium. When a solar ejection takes place close to a coronal hole, the flux rope magnetic topology of the coronal mass ejection (CME) may become misshapen at 1 AU as a result of the interaction. Detailed analysis of this event reveals erosion of the interplanetary coronal mass ejection (ICME) magnetic field. In this communication, we study the photospheric magnetic roots of the coronal hole and the coronal mass ejection area with HMI/SDO magnetograms to define their magnetic characteristics.
Magnetic instability is a key consideration for filament eruptions and subsequent CMEs. In this contribution we are considering different magnetic conditions for active and non-active regions, such as coronal hole regions and quiet sun, and also active regions of a simple magnetic configuration. The aim is to assess magnetic instability through potential and non-potential field modelling and 3D evaluation of the magnetic decay index. Some eruptive examples from solar cycle 24 using HMI/SDO data are presented, complemented with observations of AIA/SDO.
Alcarreña is an endangered Spanish sheep breed (8 009 breeding animals) characterized by its adaptation to a particularly harsh environment and by having a sustainable pasture-based, small-scale, production model. The first objective of this study was to identify the technical-economic aspects of the Alcarreña farms, based on information obtained from surveys. The second objective was to quantify the influence of slaughter weight (12, 19 and 23 kg) on the sensory characteristics of the lamb meat. The mean age of the Alcarreña sheep farmers was lower than the average age of Spanish sheep farmers; however, generational renewal is not assured because most of the farmers’ children were still in school. Mean flock size was higher than the average Spanish sheep flock. Alcarreña sheep were reared under an extensive management system, grazed year-round and had a reproductive schedule of three lambings within 2 years. The carcass and meat qualities of the 12 and 19 kg lambs did not differ significantly, although the lightest lambs had the softest meat and the clearest subcutaneous fat. The most important differences between the lighter lambs and the 23-kg lambs were in meat and fat colour and lipid composition. Among the sensorial characteristics, the 19-kg lambs had the lowest meat fibrosity, and meat colour and slaughter weight were negatively correlated.
Using the computational advantages offered by the formulation of orbital problems with respect to the ideal frame, with or without regularization, we consider the multi–revolution methods to obtain numerically the short and long–term propagation of the resulting debris clouds after a breakup event of an operational satellite. The problem posed and solved in this form gives high efficiency. We think that software with these features will serve two purposes: it will support studies of the hazards of space debris for operational orbital space systems and also will help to create debris analysis programs more transferable and reliable.
Most research on interventions to counter stigma and discrimination has
focused on short-term outcomes and has been conducted in high-income
To synthesise what is known globally about effective interventions to
reduce mental illness-based stigma and discrimination, in relation first
to effectiveness in the medium and long term (minimum 4 weeks), and
second to interventions in low- and middle-income countries (LMICs).
We searched six databases from 1980 to 2013 and conducted a
multi-language Google search for quantitative studies addressing the
research questions. Effect sizes were calculated from eligible studies
where possible, and narrative syntheses conducted. Subgroup analysis
compared interventions with and without social contact.
Eighty studies (n = 422 653) were included in the
review. For studies with medium or long-term follow-up (72, of which 21
had calculable effect sizes) median standardised mean differences were
0.54 for knowledge and −0.26 for stigmatising attitudes. Those containing
social contact (direct or indirect) were not more effective than those
without. The 11 LMIC studies were all from middle-income countries.
Effect sizes were rarely calculable for behavioural outcomes or in LMIC
There is modest evidence for the effectiveness of anti-stigma
interventions beyond 4 weeks follow-up in terms of increasing knowledge
and reducing stigmatising attitudes. Evidence does not support the view
that social contact is the more effective type of intervention for
improving attitudes in the medium to long term. Methodologically strong
research is needed on which to base decisions on investment in
Reliability and degradation processes in broad-area InGaAs-AlGaAs strained quantum well (QW) lasers are under intensive investigation because these lasers are the key components for fiber lasers and amplifiers that have found both industrial and military applications in recent years. Unlike single-mode lasers that were developed for high reliability telecom applications, broad-area lasers were mainly targeted for applications that require less stringent reliability of the lasers until recently. Especially, the lack of field reliability data is a concern for satellite communication systems where high reliability is required of lasers for long-term duration. For our present study, we addressed this concern by performing long-term life-tests of broad-area InGaAs-AlGaAs strained QW lasers and also by studying mechanisms that are responsible for catastrophic degradation of the lasers.
Stegophorus macronectes (Johnston & Mawson, 1942) is a gastrointestinal parasite found in Antarctic seabirds. The original description of the species, which was based only on females, is poor and fragmented with some unclear diagnostic characters. This study provides new morphometric and molecular data on this previously poorly described parasite. Nuclear rDNA sequences (18S, 5.8S, 28S and internal transcribed spacer (ITS) regions) were isolated from S. macronectes specimens collected from the chinstrap penguin Pygoscelis antarctica Forster on Deception Island, Antarctica. Using 18S rDNA sequences, phylogenetic analyses (maximum likelihood, maximum parsimony and Bayesian inference) of the order Spirurida were performed to determine the phylogenetic location of this species. Primer pairs of the ITS regions were designed for genus-level identification of specimens, regardless of their cycle, as an alternative to coprological methods. The utility of this molecular method for identification of morphologically altered specimens is also discussed.
We describe the preliminary design of a magnetograph and visible-light imager instrument to study the solar dynamo processes through observations of the solar surface magnetic field distribution. The instrument will provide measurements of the vector magnetic field and of the line-of-sight velocity in the solar photosphere. As the magnetic field anchored at the solar surface produces most of the structures and energetic events in the upper solar atmosphere and significantly influences the heliosphere, the development of this instrument plays an important role in reaching the scientific goals of The Atmospheric and Space Science Coordination (CEA) at the Brazilian National Institute for Space Research (INPE). In particular, the CEA's space weather program will benefit most from the development of this technology. We expect that this project will be the starting point to establish a strong research program on Solar Physics in Brazil. Our main aim is acquiring progressively the know-how to build state-of-the-art solar vector magnetograph and visible-light imagers for space-based platforms to contribute to the efforts of the solar-terrestrial physics community to address the main unanswered questions on how our nearby Star works.
Flux emergence phenomena are relevant at different temporal and spatial scales. We have studied a flux emergence region underneath a filament. This filament elevated itself smoothly, and the associated CME reached the Earth. In this study we investigate the size and the amount of flux in the emergence event. The flux emergence site appeared just beneath a filament. The emergence acquired a size of 24 Mm in half a day. The unsigned magnetic flux density from LOS-magnetograms was around 1 kG at its maximum. The transverse field as well as the filament eruption were also analysed.
This article reviews the potential of graphene and related two-dimensional (2D) materials for applications in micro- and nanoelectronics. In addition to graphene, special emphasis is placed on transition metal dichalcogenides (TMDs). First, we discuss potential solutions for application-scale material growth, in particular chemical vapor deposition. We describe challenges for electrical contacts and dielectric interfaces with 2D materials. The device-related sections in this review first weigh the pros and cons of semi-metal graphene as a field-effect transistor (FET) channel material for logic and radio frequency applications. This is followed by an introduction to alternate graphene switch concepts that utilize the particular properties of the material, namely tunnel FETs, vertical devices, and bilayer pseudospin FETs. The final section is dedicated to semiconducting TMDs and their integration in FETs using the examples of n-type molybdenum disulfide (MoS2) and p-type tungsten diselenide (WSe2).
There is little information on the population status of the ocelot Leopardus pardalis in Mexico. In the Sierra Abra-Tanchipa Biosphere Reserve, in San Luis Potosí, ocelots are affected by habitat loss and fragmentation as a result of increased agricultural development. We used photographic identification in camera-trapping capture–recapture surveys to determine population abundance and density during the dry season and subsequent early and late humid seasons during April 2011–March 2012. We recorded 80 photographs of 15 individuals (10 males, one female, and four of undetermined sex) in 7,786 camera-days. Abundance was estimated using a closed capture heterogeneity model, yielding an estimated population of 9 ± SE 3 in the dry season and 21 ± SE 8 and 15 ± SE 5 during the subsequent early and late humid seasons, respectively. Spatially explicit density estimates were 0.04 and 0.03–0.18 individuals per km2 for the dry and humid seasons, respectively, and were similar (P > 0.612) among seasons. Peaks in ocelot activity occurred during 20.00–04.00. We conclude that the ocelots of the Sierra Abra-Tanchipa Reserve have a low population density and may face geographical and biological isolation as a result of habitat conversion. Continued monitoring and improved understanding of the movements and habitat preferences of ocelots are necessary to ensure their continued persistence, and connectivity between this population and others in north-east Mexico.
We present preliminary results of a 3D MHD simulation of the convective envelope of the giant star Pollux for which the rotation period and the magnetic field intensity have been measured from spectroscopic and spectropolarimetric observations. This giant is one of the first single giants with a detected magnetic field, and the one with the weakest field so far. Our aim is to understand the development and the action of the dynamo in its extended convective envelope.
The Patagonian Batholith was formed by numerous plutonic events that took place between the Jurassic and the Miocene. North of 47° S, the youngest plutons occupy the axial zone adjacent to the Liquiñe-Ofqui Fault Zone, which is a major intra-arc strike-slip fault system active since the Miocene. The Queulat Complex, located at 44° 30′ S, includes two Miocene plutonic units: the Early Miocene Queulat diorite (QD) and the Late Miocene Puerto Cisnes granite (PCG). The QD includes hornblende + clinopyroxene diorites and tonalites, whereas the PCG includes slightly peraluminous garnet ± sillimanite granites and granodiorites.
Eleven mineral Ar–Ar ages and three apatite fission track ages were obtained from the Queulat Complex and surrounding host rocks. Hornblende and biotite Ar–Ar ages of c. 16-18 Ma and 9-10 Ma, respectively, were obtained for the QD. The youngest ages of the QD are similar to the age of emplacement of the PCG as previously determined. Ar–Ar ages for muscovites and biotites of 6·6 ± 0·3 Ma and 5·6 ± 0·1 Ma, respectively, were obtained for the PCG. Biotites and muscovites from mylonites and pelitic hornfelses adjacent to the PCG yielded Ar—Ar ages between 5·1 Ma and 5·5 Ma. The apatite fission track ages of the QD and PCG overlap within the error margin (2•2 ± 1·1-3·3 ± 1·4 Ma).
The Al-in-hornblende geobarometer yielded pressures for the QD emplacement equivalent to depths in the 19-24 km range, which is substantially higher than the 10 km depth estimated previously for the PCG emplacement. Exhumation rates (v) up to 2·0mm/yr were calculated for the time elapsed between the QD and PCG emplacements. A v value of 1·0mm/yr was calculated for the PCG subsequent to its emplacement. Using the silica—Ca-tschermak-anorthite geobarometer, we estimate the QD magma generation to be at c. 33 km, which is similar to the current crustal thickness. Melting of mafic and metapelitic lower crust was possible at > 30km depth during a period when v was between 1·0mm/yr and 2·0mm/yr.
One of the major threats to biodiversity involves biological invasions with direct consequences on the stability of ecosystems. In this context, the role of parasites is not negligible as it may enhance the success of invaders. The red-eared slider, Trachemys scripta elegans, has been globally considered among the worst invasive species. Since its introduction through the pet trade, T. s. elegans is now widespread and represents a threat for indigenous species. Because T. s. elegans coexists with Emys orbicularis and Mauremys leprosa in Europe, it has been suggested it may compete with the native turtle species and transmit pathogens. We examined parasite transfer from American captive to the two native species that co-exist in artificial pools of a Turtle Farm in France. As model parasite species we used platyhelminth worms of the family Polystomatidae (Monogenea) because polystomes have been described from American turtles in their native range. Phylogenetic relationships among polystomes parasitizing chelonian host species that are geographically widespread show patterns of diversification more complex than expected. Using DNA barcoding to identify species from adult and/or polystome eggs, several cases of host switching from exotic to indigenous individuals were illustrated, corroborating that parasite transmission is important when considering the pet trade and in reintroduction programmes to reinforce wild populations of indigenous species.
The magnetic and structural properties of sol-gel derived organic/inorganic nanocomposites doped with Fe(II), Fe(III), Nd(III) and Eu (III) ions are discussed. These hybrids consist of poly(oxyethylene)-based chains grafted onto siloxane nanodomains by urea cross-linkages. Small angle X-ray scattering data show the presence of spatial correlations of siloxane domains embedded in the polymer matrix. The magnetic properties of rare-earth doped samples are determined by single ion crystal-field-splitted levels (Eu3+ J=0; Nd3+ J=9/2) and the small thermal irreversibility is mainly associated to structural effects. Fe2+-doped samples behave as simple paramagnet with residual antiferromagnetic interactions. Fe3+-doped hybrids are much more complex, with magnetic hysterisis, exchange anisotropy and thermal irreversibility at low temperatures. Néel temperatures increase up to 14K for the highest (∼5.5%) Fe3+ mass concentration.
Trend analyses of precipitation and fog frequency, and energy balance measurements over typical examples of forest and grassland were made in the central mountain region of the State of Veracruz in eastern Mexico to examine the possibility of meso-scale climate change. It was hypothesized that changes in precipitation and fog frequency with elevation would reflect changes in the position of the lifting condensation level (LCL) and that these could be either positive or negative, depending on site elevation. The energy balance measurements were made to quantify the changes in sensible heat flux – considered the main driving force of cloud lifting – associated with the conversion of forest to pasture. In conclusion, the observed negative tendencies in dry-season precipitation (February) and overall fog frequency at lower elevations, as well as the positive tendencies seen at intermediate and higher elevations, are in line with a postulated shift in the LCL that may have been brought about by the increase in post-forest sensible heat fluxes.
The Grandes Montañas region in the State of Veracruz in eastern Mexico is part of the mountain system where the eastern end of the Eje Neovolcanico and the Sierra Madre Oriental meet. One of the main features of this region is an extremely steep topographic gradient, ranging from sea level to more than 5500 m.a.s.l., over a horizontal distance of less than 100 km. The associated climatic gradients enable the occurrence of highly diverse plant communities, ranging from relatively wet montane coniferous and cloud-affected forests to (semi-)arid vegetation types (Gómez-Pompa, 1978; Barradas, 1983).
The Sunrise balloon-borne solar observatory consists of a 1m aperture Gregory telescope, a UV filter imager, an imaging vector polarimeter, an image stabilization system and further infrastructure. The first science flight of Sunrise yielded high-quality data that reveal the structure, dynamics and evolution of solar convection, oscillations and magnetic fields at a resolution of around 100 km in the quiet Sun. Here we describe very briefly the mission and the first results obtained from the Sunrise data, which include a number of discoveries.