4,504 research outputs found
On wild extensions of a p-adic field
In this paper we consider the problem of classifying the isomorphism classes
of extensions of degree pk of a p-adic field, restricting to the case of
extensions without intermediate fields. We establish a correspondence between
the isomorphism classes of these extensions and some Kummer extensions of a
suitable field F containing K. We then describe such classes in terms of the
representations of Gal(F/K). Finally, for k = 2 and for each possible Galois
group G, we count the number of isomorphism classes of the extensions whose
normal closure has a Galois group isomorphic to G. As a byproduct, we get the
total number of isomorphism classes
Component-Resolved in Vitro Diagnosis in Peach-Allergic Patients
BACKGROUND: The in vitro diagnosis of pollen-related food allergy presents low specifi city and reproducibility with many conventional extracts. This can be improved using natural purifi ed allergens, recombinant purifi ed allergens, or both. OBJECTIVE: We compared specifi c immunoglobulin (Ig) E determination (sIgE), the basophil activation test (BAT), the histamine release test (HRT), and the cellular allergen stimulation test (CAST) using natural and recombinant allergens in the diagnosis of peach allergy. METHODS: Thirty-two peach allergic patients were studied. Skin prick tests were performed with commercial peach and extract with Mal d 1, nPru p 3, and profi lin (nPho d 2). sIgE, BAT, CAST, and HRT were determined using rPru p 3, rMal d 3, rBet v 1, rMal d 1, and rMal d 4. RESULTS: Agreement between the techniques was good with all the allergens, except HRT with rMal d 1 and rMal d 4. With rPru p 3, sIgE, CAST, BAT, and HRT showed sensitivity values of 88%, 81%, 72%, and 69% and specifi city values of 100%, 93%, 97%, and 83%, respectively. In patients with systemic symptoms or contact urticaria, the values were 100%, 85%, 81%, and 81%. In patients with oral allergy syndrome, sensitivity to profi lins or homologues of Bet v 1 was detected in 100% of the cases by all the techniques, except by HRT with rMal d 1, which detected 66% of the cases. CONCLUSIONS: The use of single allergens in the in vitro diagnosis of peach allergy by specifi c IgE determination, BAT, and CAST offers high specifi city and sensitivity, with better results than the HRT
INDIGO : better geomagnetic observatories where we need them
The INDIGO project aims to improve the global coverage of digital observatories by deploying digital magnetometer systems in:
i) Observatories where existing analog recording equipment is in need of upgrading.
ii) Newly established digital observatories.
iii) Existing digital observatories for the purpose of quality control and redundancy.
In implementing the project and selecting suitable sites, special attention is paid to parts of the Earth devoid of magnetic observatories, increasing the reliability and long-term operation of existing observatories and cost-effective use of local resources.
The Poster reviews the current status of the project. We examine the different steps and initiatives taken since the initiation of INDIGO in 2004 and assess their effectiveness in achieving progress towards our aims of improving global coverage and enhanced data quality
Design of Force Fields from Data at Finite Temperature
We investigate the problem of how to obtain the force field between atoms of
an experimentally determined structure. We show how this problem can be
efficiently solved, even at finite temperature, where the position of the atoms
differs substantially from the ground state. We apply our method to systems
modeling proteins and demonstrate that the correct potentials can be recovered
even in the presence of thermal noise.Comment: 10 pages, 1 postcript figure, Late
Deuteration as an evolutionary tracer in massive-star formation
Theory predicts, and observations confirm, that the column density ratio of a
molecule containing D to its counterpart containing H can be used as an
evolutionary tracer in the low-mass star formation process. Since it remains
unclear if the high-mass star formation process is a scaled-up version of the
low-mass one, we investigated whether the relation between deuteration and
evolution can be applied to the high-mass regime. With the IRAM-30m telescope,
we observed rotational transitions of N2D+ and N2H+ and derived the deuterated
fraction in 27 cores within massive star-forming regions understood to
represent different evolutionary stages of the massive-star formation process.
Results. Our results clearly indicate that the abundance of N2D+ is higher at
the pre-stellar/cluster stage, then drops during the formation of the
protostellar object(s) as in the low-mass regime, remaining relatively constant
during the ultra-compact HII region phase. The objects with the highest
fractional abundance of N2D+ are starless cores with properties very similar to
typical pre-stellar cores of lower mass. The abundance of N2D+ is lower in
objects with higher gas temperatures as in the low-mass case but does not seem
to depend on gas turbulence. Our results indicate that the N2D+-to-N2H+ column
density ratio can be used as an evolutionary indicator in both low- and
high-mass star formation, and that the physical conditions influencing the
abundance of deuterated species likely evolve similarly during the processes
that lead to the formation of both low- and high-mass stars.Comment: Accepted by A&AL, 4 pages, 2 figures, 2 appendices (one for Tables,
one for additional figures
The GUAPOS project: G31.41+0.31 Unbiased ALMA sPectral Observational Survey. IV. Phosphorus-bearing molecules and their relation with shock tracers
The astrochemistry of the important biogenic element phosphorus (P) is still
poorly understood, but observational evidence indicates that P-bearing
molecules are likely associated with shocks. We study P-bearing molecules, as
well as some shock tracers, towards one of the chemically richest hot molecular
core, G31.41+0.31, in the framework of the project "G31.41+0.31 Unbiased ALMA
sPectral Observational Survey" (GUAPOS), observed with the Atacama Large
Millimeter Array (ALMA). We have observed the molecules PN, PO, SO, SO2, SiO,
and SiS, through their rotational lines in the spectral range 84.05-115.91 GHz,
covered by the GUAPOS project. PN is clearly detected while PO is tentatively
detected. The PN emission arises from two regions southwest of the hot core
peak, "1" and "2", and is undetected or tentatively detected towards the hot
core peak. the PN and SiO lines are very similar both in spatial emission
morphology and spectral shape. Region "1" is in part overlapping with the hot
core and it is warmer than region "2", which is well separated from the hot
core and located along the outflows identified in previous studies. The column
density ratio SiO/PN remains constant in regions "1" and "2", while SO/PN,
SiS/PN, and SO2/PN decrease by about an order of magnitude from region "1" to
region "2", indicating that SiO and PN have a common origin even in regions
with different physical conditions. Our study firmly confirms previous
observational evidence that PN emission is tightly associated with SiO and it
is likely a product of shock-chemistry, as the lack of a clear detection of PN
towards the hot-core allows to rule out relevant formation pathways in hot gas.
We propose the PN emitting region "2" as a new astrophysical laboratory for
shock-chemistry studiesComment: 15 pages, 11 figures, accepted for publication in A&
Modelling the mid-late Holocene evolution of the Huelva Estuary and its human colonization, South-Western Spain
The major changes that occurred in the southwestern estuaries of the Spanish Atlantic coast during the last 6500 yr BP were
simultaneous to human settlement and therefore the understanding of their coastal evolution will help interpreting human patterns in
these areas. The study of the morpho-sedimentary features of new outcrops appearing in the middle sector of Saltés Island (Huelva
Estuary, Spain) has been used to develop a model to understand the complex evolution of sand barriers than can be applied to
similar inlets along the Atlantic Iberian coast.
The first human settlements (6000–4000 yr BP) in the early Huelva Estuary (Tinto and Odiel rivers) were located in the ancient coastal
banks or in the nearby hills. From 4000 yr BP onwards, the estuarine sediments started to emerge as sand barriers and chenier plains,
prograding towards the mouth. As the littoral strands stabilized morphologically, they were colonized by human settlements in successive
periods, the oldest inland (Almendral) and more recent outward (Cascajera). The study of the upper sedimentary layers of La Cascajera
barrier display a tempestitic sequence of landward progradational washover-fans. The calibrated and modelled AMS dates in marine shells
provide a storminess time range between the second half of first century BCE and the entire first century CE.
Sedimentary records are useful to evaluate environmental changes, either from natural or anthropogenic causes, such as global and
climate change. The interrelationship between the archaeological findings (mainly salting fish factories and old ports) and the morpho sedimentary evolution at the mouth of the Tinto and Odiel rivers allows us to highlight not only the Huelva Estuary's dynamics evolution,
but also the possible regional patterns of human habitation from the beginning of the present sea-level highstand (middle Holocene).Ministerio de Economía y Competitividad CGL2010-15810/BTEEuropean Union (UE) EU Excellence Project of the Andalusia Board SEJ-477
The materials production and processing facility at the Spanish National Centre for fusion technologies (TechnoFusión)
Proceedings of : The 26th Symposium of Fusion Technology (SOFT-26), Porto (Portugal),- 27 september - 1 october 2010.In response to the urgent request from the EU Fusion Program, a new facility (TechnoFusion) for research and development of fusion materials has been planned with support from the Regional Government of Madrid and the Ministry of Science and Innovation of Spain. TechnoFusion, the National Centre for Fusion Technologies, aims screening different technologies relevant for ITER and DEMO environments while promoting the contribution of international companies and research groups into the Fusion Programme. For this purpose, the centre will be provided with a large number of unique facilities for the manufacture, testing (a triple-beam multi-ion irradiation, a plasma-wall interaction device, a remote handling for under ionizing radiation testing) and analysis of critical fusion materials. Particularly, the objectives, semi-industrial scale capabilities and present status of the TechnoFusion Materials Production and Processing (MPP) facility are presented. Previous studies revealed that the MPP facility will be a very promising infrastructure for the development of new materials and prototypes demanded by the fusion technology and therefore some of them will be here briefly summarized.This work has been supported by Madrid Community through
the project TECHNOFUSION (S2009/ENE/1679).Publicad
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