1,050 research outputs found
Fractal Topological Analysis for 2D Binary Digital Images
Fractal dimension is a powerful tool employed as a measurement of geometric aspects. In this work we
propose a method of topological fractal analysis for 2D binary digital images by using a graph-based topological
model of them, called Homological Spanning Forest (HSF, for short). Defined at interpixel level, this set of two
trees allows to topologically describe the (black and white) connected component distribution within the image
with regards to the relationship “to be surrounded by”. This distribution is condensed into a rooted tree, such that its
nodes are connected components determined by some special sub-trees of the previous HSF and the levels of the tree
specify the degree of nesting of each connected component. We ask for topological auto-similarity by comparing
this topological description of the whole image with a regular rooted tree pattern. Such an analysis can be used to
directly quantify some characteristics of biomedical images (e.g. cells samples or clinical images) that are not so
noticeable when using geometrical approaches.Ministerio de Economía y Competitividad TEC2016-77785-PMinisterio de Economía y Competitividad MTM2016-81030-
NGC 6705 a young -enhanced Open Cluster from OCCASO data
The stellar [/Fe] abundance is sometimes used as a proxy for stellar
age, following standard chemical evolution models for the Galaxy, as seen by
different observational results. In this work we show that the Open Cluster
NGC6705/M11 has a significant -enhancement [/Fe] dex,
despite its young age (300 Myr), challenging the current paradigm. We use
high resolution (R) high signal-to-noise (70) spectra of 8 Red
Clump stars, acquired within the OCCASO survey. We determine very accurate
chemical abundances of several elements, using an equivalent width
methodology (Si, Ca and Ti), and spectral synthesis fits (Mg and O). We obtain
[Si/Fe]=, [Mg/Fe]=, [O/Fe]=,
[Ca/Fe]= and [Ti/Fe]=. Our results place these
cluster within the group of young [/Fe]-enhanced field stars recently
found by several authors in the literature. The ages of our stars have an
uncertainty of around 50 Myr, much more precise than for field stars. By
integrating the cluster's orbit in several non-axisymmetric Galactic
potentials, we establish the M11's most likely birth radius to lie between
6.8-7.5 kpc from the Galactic center, not far from its current position. With
the robust Open Cluster age scale, our results prove that a moderate
[/Fe]-enhancement is no guarantee for a star to be old, and that not
all -enhanced stars can be explained with an evolved blue straggler
scenario. Based on our orbit calculations, we further argue against a Galactic
bar origin of M11.Comment: 10 pages, 6 figures, accepted in A&
Descripción de la cohorte PROCOAC (PROspective COhort of A Coruña): Cohorte prospectiva española para el estudio de la osteoartritis
[Abstract] Introduction and objective: The use of well characterized osteoarthritis (OA) cohorts is mandatory for the study and knowledge of this disease. Currently, there is no prospective cohort in this pathology in Spain. The objective of this work is to describe the first osteoarthritis cohort in Spain, PROCOAC (Cohort PROspectiva de A Coruña).
Methods: The Unit of Rheumatology of the University Hospital of A Coruña started a prospective follow-up study in 2006. The patient inclusion criteria were: I) Patients older than 55 years who underwent an abdominal x-ray to study both hips II) Patients diagnosed with radiographic hand OA according to ACR criteria III) Patients diagnosed with radiographic knee or hip OA according to ACR criteria. Follow-up was performed every two years collecting clinical, analytical, genetic and radiographic information.
Results: The cohort consists of 937 patients, 873 have radiographic knee OA, 783 hip OA and 679 hand OA. The mean age of the population is 63.9±8.9 years and the average BMI is 29.6±5.1. More than half of the population has high blood pressure and 17% diabetes. The predominant osteoarthritis in the hand is nodular (78.1%), followed by trapeziometacarpal (55.3%) and erosive (18.4%). Twenty-one point four percent and 43.1% are healthy at knee and hip level respectively; observing a grade 1 in 26% and 37%; a grade 2 in 26.7% and 11.5%; a grade 3 in 14.9% and 4%; and a grade 4 in 9.4% and 3.7% respectively. Of the population, 44.1% has only 1 joint affected, 39.9% has 2 and 13.4% has 3 joints affected. Age (OR=1.11; p<.001), BMI (OR=1.11; p=.002) and total WOMAC (OR=1.03; p=.005) are the only risk factors if we compare the involvement of a single location versus three. A discrepancy between pain and radiographic damage at the joint level was also detected in patients with KL≤2 grade, and therefore a significantly higher percentage of patients with knee OA experienced pain (66.1%) compared to patients with OA hip (21.1%) (p<.001).
Conclusions: The PROCOAC cohort is an instrument that allows studies of incidence and progression in hand, knee and hip OA; as well as determining factors that are associated with the different OA phenotypes.[Resumen] Introducción y objetivo. El uso de cohortes de Osteoartritis (OA) bien caracterizadas es obligatorio para estudiar y profundizar en el conocimiento en esta enfermedad. En España no existe actualmente ninguna cohorte prospectiva en esta patología; así el objetivo de este trabajo es describir la primera cohorte de Osteoartritis en España, la PROCOAC (PROspective COhort of A Coruña).
Material y métodos. El Servicio de Reumatología del Hospital Universitario de A Coruña inició un estudio de seguimiento prospectivo en el año 2006. Los criterios de inclusión fueron: I) Pacientes mayores de 55 años a los que se les realizó una radiografía abdominal que permitiese estudiar ambas caderas II) Pacientes diagnosticados de OA radiográfica de mano según los criterios ACR III) Pacientes diagnosticados de OA radiográfica de rodilla y/o cadera según los criterios ACR. Se realizó seguimiento cada dos años recogiendo información clínica, analítica, genética y radiográfica.
Resultados. La cohorte consta de 937 individuos, 873 tienen OA radiográfica de rodilla, 783 de cadera y 679 de mano. La edad media de la población es 63,9 ± 8,9 años y el IMC promedio de 29,6 ± 5,1. Más de la mitad de la población tiene hipertensión arterial y el 17% diabetes. La osteoartritis predominate en la mano es la nodular (78,1%), seguida de la rizartrosis (55,3%) y la erosiva (18,4%). El 21,4% y el 43,1% son sanos a nivel de rodilla y cadera respectivamente; observando un grado 1 en el 26% y 37%; un grado 2 en el 26,7% y 11,5%; un grado 3 en el 14,9% y 4%; y un grado 4 en el 9,4% y 3,7% respectivamente. El 44,1% de la población tiene 1 articulación afectada, el 39,9% tiene 2 y el 13,4% tiene 3 articulaciones afectadas. La edad (OR = 1,11; p < 0,001), el IMC (OR = 1,11; p = 0,002) y el WOMAC total (OR = 1,03; p = 0,005) son los únicos factores de riesgo si comparamos la afectación de una sola ubicación frente a tres. También se detectó una discrepancia entre el dolor y el daño radiográfico a nivel articular en pacientes con grado KL ≤ 2, de modo que un porcentaje significativamente mayor de pacientes con OA de rodilla experimentaron dolor (66,1%) en comparación con pacientes con OA de cadera (21,1%) (p < 0,001).
Conclusión. La cohorte PROCOAC es un instrumento que permite realizar estudios de incidencia y pro-gresión en la osteoartritis de mano, rodilla y cadera, así como conocer factores que se asocian con losdiferentes fenotipos de osteoartritis
Promiscuous mismatch extension by human DNA polymerase lambda
DNA polymerase lambda (Pol λ) is one of several DNA polymerases suggested to participate in base excision repair (BER), in repair of broken DNA ends and in translesion synthesis. It has been proposed that the nature of the DNA intermediates partly determines which polymerase is used for a particular repair reaction. To test this hypothesis, here we examine the ability of human Pol λ to extend mismatched primer-termini, either on ‘open’ template-primer substrates, or on its preferred substrate, a 1 nt gapped-DNA molecule having a 5′-phosphate. Interestingly, Pol λ extended mismatches with an average efficiency of ≈10−2 relative to matched base pairs. The match and mismatch extension catalytic efficiencies obtained on gapped molecules were ≈260-fold higher than on template-primer molecules. A crystal structure of Pol λ in complex with a single-nucleotide gap containing a dG·dGMP mismatch at the primer-terminus (2.40 Å) suggests that, at least for certain mispairs, Pol λ is unable to differentiate between matched and mismatched termini during the DNA binding step, thus accounting for the relatively high efficiency of mismatch extension. This property of Pol λ suggests a potential role as a ‘mismatch extender’ during non-homologous end joining (NHEJ), and possibly during translesion synthesis
The state of the art in integrating machine learning into visual analytics
Visual analytics systems combine machine learning or other analytic techniques with interactive data visualization to promote sensemaking and analytical reasoning. It is through such techniques that people can make sense of large, complex data. While progress has been made, the tactful combination of machine learning and data visualization is still under-explored. This state-of-the-art report presents a summary of the progress that has been made by highlighting and synthesizing select research advances. Further, it presents opportunities and challenges to enhance the synergy between machine learning and visual analytics for impactful future research directions
Swine enteric colibacillosis in Spain: pathogenic potential of mcr-1 ST10 and ST131 E. coli Isolates
This is a wide epidemiological study of 499 E. coli isolates recovered from 179 outbreaks of enteric colibacillosis from pig production farms in Spain during a period of 10 years. Most samples were of diarrheagenic cases occurred during the post-wean period (PWD) which showed to be significantly associated with ETEC (67%) followed by aEPEC (21.7%). On the contrary, aEPEC was more prevalent (60.3%) among diarrheas of suckling piglets, followed by ETEC (38.8%). STEC/ETEC or STEC were recovered in 11.3 and 0.9% of PWD and neonatal diarrhea, respectively. Detection of the F4 colonization factor was not significantly different between isolates recovered from neonatal pigs and those recovered post wean (40.5 versus 27.7%) while F18 was only present among PWD isolates (51.5% of ETEC, STEC, and STEC/ETEC isolates). We also found a high prevalence of resistance to colistin related to the presence of the mcr-1 gene (25.6% of the diarreagenic isolates). The characterization of 65 representative mcr-1 isolates showed that all were phenotypically resistant to colistin (>2 μg/ml), and most (61 of 65) multidrug-resistant (MDR). Six ETEC and one STEC mcr-1 isolates were also carriers of ESBL genes. In addition, other seven mcr-1 isolates harbored mcr-4 (three ETEC) and mcr-5 (two ETEC and two aEPEC) genes. In the phylogenetic analysis of the 65 mcr-1 diarrheagenic isolates we found that more than 50% (38 out of 65) belonged to A-ST10 Cplx and from those, 29 isolates showed the clonotype CH11-24. In this study, we also recovered 18 ST131 isolates including seven mcr-1 carriers. To the best of our knowledge, this would be the first report of ST131 mcr-1 isolation in pigs. Worryingly, the swine mcr-1 ST131 carriers also showed MDR, including to trimethoprim-sulfamethoxazole, tobramycin, gentamicin and ciprofloxacin. In the PFGE-macrorestriction comparison of clinical swine and human ST131, we found high similarities (≥85%) between two pig and two human ST131 isolates of virotype D5. Acquisition of mcr-1 by this specific clone means an increased risk due to its special feature of congregating virulence and resistance traits, together with its spread capability. Here we show a potential zoonotic swine source of ST131This study was supported by projects AGL2016-79343-R from the Agencia Estatal de Investigación (AEI, Spain) and FEDER; PI16/01477 from Plan Estatal de I C D C I 2013–2016, Instituto de Salud Carlos III (ISCIII), Subdirección General de Evaluación y Fomento de la Investigación, and FEDER; CN2012/303 andED431C 2017/57 from the Consellería de Cultura, Educación e Ordenación Universitaria (Xunta de Galicia), and FEDER
IG-M acknowledges the Conselleria de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia for his grant (Ref. ED481A-2015/149) “Axudas de apoio á etapa predoutoral do Plan galego de investigación, innovación e crecemento 2011-2015S
Effects of A Concentrate Rich in Agro-Industrial By-Products on Productivity Results, Carcass Characteristics and Meat Quality Traits of Finishing Heifers
Finishing diets in intensive beef production systems are mainly based on cereals, which does not take advantage of the capacity of the ruminant digestive system to digest fibrous feeds, cannot be considered sustainable and does not contribute to the circular bioeconomy. Our aim was to investigate the effects of an alternative concentrate rich in agro-industrial by-products for finishing crossbred Limousine heifers. Four pens with 12 heifers and four pens with 13 heifers were randomly allocated to one of two treatments: control (CON), a commercial concentrate with a 43.3% cereal composition, and alternative (ALT), a concentrate with a composition of 26% cereals and up to 73.5% agro-industrial by-products. Growth performance data were collected along the 91 days of the experimental period. Carcass characteristics were collected after slaughter and 24 h later. Vacuum-packaged samples from longissimus muscle were aged for 7, 21 or 28 days to study meat quality traits. Feed intake was higher and feed conversion rate was lower in the ALT treatment, but no differences were found in average daily gain and feeding costs. Treatment had no effects on any of the measured carcass traits (grading, hot and cold carcass weight, dressing out, chilling losses, subcutaneous fat depth, pH, temperature and lean and fat colour) nor on the meat quality traits (drip loss, cooking loss, shear force, oxidative stability, chromatic indices and pigment contents). Ageing time decreased drip loss and shear force, increased lightness and did not affect redness or surface colour stability. In conclusion, feeding crossbred Limousine heifers a finishing diet rich in agro-industrial by-products did not have any negative effects on performance, carcass and meat quality traits, which might be considered positive from the point of view of sustainability of beef production. Under the conditions assayed, ageing for 21 and 28 days improved tenderness of meat, without detrimental effects on oxidative stability or traits related to visual acceptability
Oscillatory Modes of a Prominence-PCTR-Corona Slab Model
Oscillations of magnetic structures in the solar corona have often been
interpreted in terms of magnetohydrodynamic waves. We study the adiabatic
magnetoacoustic modes of a prominence plasma slab with a uniform longitudinal
magnetic field, surrounded by a prominence-corona transition region (PCTR) and
a coronal medium. Considering linear small-amplitude oscillations, the
dispersion relation for the magnetoacoustic slow and fast modes is deduced
assuming evanescent-like perturbations in the coronal medium. In the system
without PCTR, a classification of the oscillatory modes according to the
polarisation of their eigenfunctions is made in order to distinguish modes with
fast-like or slow-like properties. Internal and external slow modes are
governed by the prominence and coronal properties respectively, and fast modes
are mostly dominated by prominence conditions for the observed wavelengths. In
addition, the inclusion of an isothermal PCTR does not substantially influence
the mode frequencies, but new solutions (PCTR slow modes) are present.Comment: Accepted for publication in Solar Physic
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