We present a case of a 67-year-old man who was an active smoker, with a clinical history of ischaemic cardiopathy, hypertension, who presented to the emergency room with hoarseness of voice of 2 ...weeks duration. No other neurological or cardiorespiratory symptoms were found. Physical examination revealed an aortic regurgitation murmur with radial pulse difference between the upper limbs and femoral pulse difference on lower limbs. Laryngoscopy examination revealed a left vocal cord paralysis in the paramedian position, without signs of malignancy. Thoracoabdominal CT angiography was performed to rule out an aortic dissection. CT revealed a dissection in the descending thoracic aortic arch and abdominal aorta. Cardiovascular surgery was consulted and decided to place endoprosthesis at the thoracic and abdominal aortic area. Hoarseness eventually resolved during the following weeks. Ortner’s syndrome is described as hoarseness of voice caused by compression of the left recurrent laryngeal nerve of cardiovascular origin.
Gaia broad band photometry Jordi, C.; Gebran, M.; Carrasco, J. M. ...
Astronomy and astrophysics (Berlin),
11/2010, Letnik:
523
Journal Article
Recenzirano
Odprti dostop
Aims. The scientific community needs to be prepared to analyse the data from Gaia, one of the most ambitious ESA space missions, which is to be launched in 2012. The purpose of this paper is to ...provide data and tools to predict how Gaia photometry is expected to be. To do so, we provide relationships among colours involving Gaia magnitudes (white light G, blue GBP, red GRP and GRVS bands) and colours from other commonly used photometric systems (Johnson-Cousins, Sloan Digital Sky Survey, Hipparcos and Tycho). Methods. The most up-to-date information from industrial partners has been used to define the nominal passbands, and based on the BaSeL3.1 stellar spectral energy distribution library, relationships were obtained for stars with different reddening values, ranges of temperatures, surface gravities and metallicities. Results. The transformations involving Gaia and Johnson-Cousins V − IC and Sloan DSS g − z colours have the lowest residuals. A polynomial expression for the relation between the effective temperature and the colour GBP − GRP was derived for stars with Teff ≥ 4500 K. For stars with Teff < 4500 K, dispersions exist in gravity and metallicity for each absorption value in g − r and r − i. Transformations involving two Johnson or two Sloan DSS colours yield lower residuals than using only one colour. We also computed several ratios of total-to-selective absorption including absorption AG in the G band and colour excess E(GBP–GRP) for our sample stars. A relationship involving AG / AV and the intrinsic (V − IC) colour is provided. The derived Gaia passbands have been used to compute tracks and isochrones using the Padova and BASTI models. Finally, the performances of the predicted Gaia magnitudes have been estimated according to the magnitude and the celestial coordinates of the star. Conclusions. The provided dependencies among colours can be used for planning scientific exploitation of Gaia data, performing simulations of the Gaia-like sky, planning ground-based complementary observations and for building catalogues with auxiliary data for the Gaia data processing and validation.
This paper presents a study of susceptibility to hydrogen embrittlement of API 5L X80 steel welded joints by SMAW and GTAW processes. By varying the consumables used and the use of the same interpass ...temperature three different welded joints were obtained. Tests of hydrogen embrittlement susceptibility were performed according to ASTM G129-2006 with an aqueous solution (Solution A - TM0177/2005 NACE) sodium thiosulfate (Na sub(2)S sub(2)O sub(3)) replacing the bubbling of H sub(2)S. From the elongation values was observed that the joint obtained in all welding conditions showed susceptibility to hydrogen embrittlement, which was determined by the elongation ratio. The joints that showed higher levels of hardness showed higher susceptibility to hydrogen embrittlement. The joints obtained with higher welding speeds for the same amount of heat input presented a reduction in the rate of hydrogen embrittlement. All joints tested in solution showed fracture surfaces with quasi cleavage zones.
The purpose of this study is to compare the suitability of five laboratory methods for predicting the ash sintering occurring during the combustion of biomass. The studied methods have been the ...following: fusibility under DIN norms, measurement of the compression strength of ash pellet previously heated at different temperatures, manual disintegration of biomass ash obtained at different temperatures, relation alkaline earth oxides to alkaline oxides, and representation in a ternary phase diagram SiO
2–CaO–K
2O. The two last theoretical methods are based on the analysis of biomass ash elements.
The ash sintering behaviour results obtained with these methods for different biomasses have been compared with the ash sintering results obtained in combustion tests of the same biomasses in a 1
MWth bubbling fluidised bed combustion (BFBC) pilot plant, with silica as initial bed material.
The compression method does not predict adequately the ash sintering behaviour of woody fuels and other biomasses with a lower content in alkaline elements. The disintegration and fusibility methods predict with success the sintering behaviour of most of the tested biomasses. Both theoretical methods have been less reliable to predict the ash sintering behaviour than disintegration and fusibility test methods.
Neolithic, Chalcolithic and Bronze Age anthropogenic cave sediments from three caves from northern Spain have been palaeomagnetically investigated. 662 oriented specimens corresponding to 39 burning ...events (ash–carbonaceous couplets) from the three sites with an average of 16 samples per fire were collected. 26 new archaeomagnetic directions have been obtained for the time period ranging from 5500 to 2000 yr cal. BC. These results represent the oldest archaeomagnetic directions obtained from burnt archaeological materials throughout all Western Europe. Magnetisation is carried by pseudo-single domain low-coercivity ferromagnetic minerals (magnetite, magnetite with no significant isomorphous substitution and/or maghaemite). Rock-magnetic experiments indicate a thermoremanent origin of the magnetisation although a thermochemical magnetisation cannot be excluded. Combination of the new data presented here and the recent updated Bulgarian database allows us to propose the first European palaeosecular variation (PSV) curve for the Neolithic. A bootstrap method was applied for the curve construction using penalised cubic B-splines in time. The new palaeosecular variation curve is well constrained from 6000 BC to 3700 BC, the period with the highest density of data, showing a declination maximum around 4700 BC and a minimum in inclination at 4300 BC, which are not recorded by the recent global CALS10K.1b and regional SCHA.DIF.8K models due to the use of lake sediment data. Dating resolution by using the proposed PSV curve oscillates from approximately ±30 yr to ±200 yr for the period 6000 to 1000 yr BC, reaching similar resolution as radiocarbon dating. Considering the good preservation, age-control and widespread occurrence of burnt archaeological materials across Southern Europe, they represent a new source of data for geomagnetic field modelling, as well as for archaeomagnetic dating.
•Discovery of a new geomagnetic field recorder: anthropogenic cave sediments.•Oldest archaeomagnetic directions for Western Europe (26 new data; 5500–2000 BC).•First European directional secular variation curve for the Neolithic based on archaeomagnetic data.•This new dating curve for the moment has dating resolution as precise as radiocarbon.•Future use of these materials in archaeomagnetism will increase the accuracy of this dating technique.
The
k nearest neighbor (
k-
NN) classifier has been a widely used nonparametric technique in Pattern Recognition, because of its simplicity and good performance. In order to decide the class of a new ...prototype, the
k-
NN classifier performs an exhaustive comparison between the prototype to classify and the prototypes in the training set
T. However, when
T is large, the exhaustive comparison is expensive. For this reason, many fast
k-
NN classifiers have been developed, some of them are based on a tree structure, which is created during a preprocessing phase using the prototypes in
T. Then, in a search phase, the tree is traversed to find the nearest neighbor. The speed up is obtained, while the exploration of some parts of the tree is avoided using pruning rules which are usually based on the triangle inequality. However, in soft sciences as Medicine, Geology, Sociology, etc., the prototypes are usually described by numerical and categorical attributes (mixed data), and sometimes the comparison function for computing the similarity between prototypes does not satisfy metric properties. Therefore, in this work an approximate fast
k most similar neighbor classifier, for mixed data and similarity functions that do not satisfy metric properties, based on a tree structure (Tree
k-
MSN) is proposed. Some experiments with synthetic and real data are presented.
Abstract
The metal phytoextraction potential of three legumes belonging to different genera has been studied under greenhouse conditions. Legumes accumulate As and metals mainly in roots, although ...translocation to shoot is observed. Alfalfa did accumulate the highest concentrations of As and metals in shoots and aerial biomass was less affected by the toxic elements, indicating its good behaviour in phytoextraction. Clover accumulated less metal, but showed larger biomass. EDTA addition enhanced Pb phytoextraction up to levels similar to those described for plants proposed in phytoremediation. The regulation of O-acetylserine (thiol)lyase from legumes under metal stress has been analysed to test the possibility of establishing a possible correlation between the expression of OASTL in the presence of the metals and the metal accumulation in legume plant tissues. Cd and Pb(EDTA) produce the strongest increases of OASTL activity, with the higher enhancement seen in roots, in parallel with the higher metal accumulation. Arsenic produced an increase of root enzyme activity, whereas Cu produced a decrease, mainly in shoots. Western blots using antibodies against an A. THALIANA cytosolic OAS‐TL recognised up to five protein bands in crude extracts from LOTUS and clover. A low molecular weight isoform of 32 kDa was induced in the presence of Cd and Pb. A partial RT‐PCR sequence from clover has been obtained, showing 86 - 97 % identity with other described OASTLs. The PCR fragment has been used to analyse OASTL mRNA levels of legumes under metal stress. OASTL transcripts were increased by As, Cd, and Pb, especially in roots, where metal accumulation was maximal, while Cu produced a decrease in the transcript levels.
Even though research has been conducted on the employment integration at blind people, studies have failed to consider what teachers think and know about their blind students’ difficulties entering ...the workforce after completing their education. The aim of this qualitative study was to understand the subjective theories of six teachers from a school in La Serena, Chile. In-depth interviews were used to collect data, which were subsequently studied using grounded theory coding procedures and subjective theory content analysis. The main finding of this study was that participants regarded the inadequate education of blind people as the key reason for their employment difficulties. This study can provide valuable information for policymakers focusing on visual impairment.
Negative interactions between guanacos Lama guanicoe and ranchers have recently intensified in central Chile because guanacos are perceived to be competing with livestock for pasture resources. We ...examined this conservation conflict with a novel approach that considers ranchers' subjective theories, to better understand the origins of the conflict and to identify effective conservation measures based on the participants' explanations. Our findings indicate that ranchers see the source of the current problem in a shift towards increasingly arid conditions associated with climate change. We suggest the ranchers’ perceived problems are not only caused by interspecific resource competition arising from this climatic shift, but also by reported difficulties in negotiating with governmental institutions. This study adds to knowledge of human–wildlife interactions by exploring a further dimension of the complex ecological and social interactions taking place on livestock farms. We recommend identifying effective, acceptable solutions by considering and understanding the everyday knowledge of the conflict's protagonists and their potential for change.
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