2,162 research outputs found
Asymptotic normality for the counting process of weak records and \delta-records in discrete models
Let be a sequence of independent and identically distributed
random variables, taking non-negative integer values, and call a
-record if , where is an
integer constant. We use martingale arguments to show that the counting process
of -records among the first observations, suitably centered and
scaled, is asymptotically normally distributed for . In particular,
taking we obtain a central limit theorem for the number of weak
records.Comment: Published at http://dx.doi.org/10.3150/07-BEJ6027 in the Bernoulli
(http://isi.cbs.nl/bernoulli/) by the International Statistical
Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm
Necrópolis de incineración y arquitectura funeraria en el noreste de la Península Ibérica durante el Bronce Final y la Primera Edad del Hierro
En este artículo presentamos un estado de la cuestión sobre las necrópolis de incineración del Bronce Final y Primera Edad del Hierro en el noreste peninsular. Para ello, analizamos el ritual funerario, la organización interna de las necrópolis y muy especialmente su arquitectura funeraria para, en base a ella, caracterizar el proceso de regionalización que se observa en el territorio.In this paper we evaluate the present knowledge on cremation cemeteries from the Late Bronze and Early Iron Age periods in the Northeast of the Iberian Peninsula. We analyze the funerary rites as well as the internal organization of the necropolis paying special attention to the funerary architecture. Our main goal is to characterize the regionalism observed in the territory
Reflexiones sobre la contribución del Tribunal Penal Internacional para la antigua Yugoslavia al desarrollo del Derecho Internaciona Humanitario
Understanding the impact of line-of-sight in the ergodic spectral efficiency of cellular networks
In this paper we investigate the impact of lineof-sight (LoS) condition in the ergodic spectral efficiency of cellular networks. To achieve this goal, we have considered the kappa-mu shadowed model, which is a general model that provides an excellent fit to a wide set of propagation conditions. To overcome the mathematical complexity of the analysis, we have split the analysis between large and small-scale effects. Building on the proposed framework, we study a number of scenarios that range from heavily-fluctuating LoS to deterministic-LoS. Finally, we shed light on the interplay between fading severity and spectral efficiency by means of the amount of fading.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Comensalitat durant el bronze final i la primera edat del ferro al paratge arqueològic de Can Roqueta: anàlisi dels dipòsits relacionats amb el consum en contextos domèstics i funeraris
La reconstrucció de les pautes de consum d"aliments durant el bronze final i la primera edat de ferro, tant si són de caire domèstic com si no, passa per un anàlisi exhaustiu de les diferents dades arqueològiques. En primer lloc, tenim els espais destinats al consum. Les circumstàncies pròpies del registre arqueològic a Catalunya durant aquests períodes fa que, depèn del territori, aquest nivell d"anàlisi sigui més o menys evident. Així, en territoris on existeix una tradició arquitectònica en pedra i, fins i tot, dissenys urbanístics ben definits (entorn del Segre i l"Ebre), aquest problema resulta relativament fàcil de tractar en funció de la conservació de la resta d"elements i la particularitat de les estructures analitzades. Això ha permès caracteritzar certes pràctiques.de consum diferenciades del que podria ser propi d"un àmbit domèstic en jaciments com Barranc de Gàfols (habitacions 1 y 2), la Moleta del Remei (habitació 7), Tossal Redó (habitació 1), San Cristóbal (habitació 2), Sant Jaume Mas d"en Serrà (habitacions 3 i 4), l"edifici de Turó del Calvari de Vilalba dels Arcs o Genó (habitació 2) (Lucas 1989; López Cachero 1998; Sanmartí et al. 2000; Fatás 2004-05; Garcia 2005; Sardà 2008). Aquesta situació contrasta amb el que passa a la resta del litoral català on les estructures negatives són pràcticament l"única evidència del poblament existent i on resulta molt complicat, fins i tot, la documentació de qualsevol espai habitacional que ens permeti avançar en aquesta direcció
Functional Value of Amaranth as Applied to Sports Nutrition
Amaranth can be beneficial to health and sports, with multiple applications owing to varied concentration of phytochemical; the concentration of these compounds depends on the part or by-product employed. For example, as a food supplement, amaranth oil (rich in squalene) can exert cardiovascular properties, while amaranth extract (rich in nitrites) can increase nitric oxide production (therefore improving endurance performance). On the other hand, as a functional ingredient, its gluten-free flours (containing fibre) can act as probiotics, whereas its proteins (with a peculiar amino acid profile) support muscle recovery. The few clinical results with athletic population suggest it can contribute to improved aerobic metabolism, but there is insufficient clinical data to draw any conclusion. Further research warrants elucidation of amaranth phytochemicals as promising ergogenic aids in sports by high-quality human clinical trials with both standardised products and ingredients in athletic population
School leadership. A review of current research perspectives
Ante el fracaso –o los efectos muy limitados- de muchas de las reformas externas intentadas en las últimas décadas, el liderazgo educativo es percibido como un elemento clave para generar mejora desde abajo, creando condiciones institucionales que hagan más eficaces las organizaciones escolares. A partir de una revisión de la literatura internacional actual, este artículo se propone delimitar algunos de los enfoques relevantes de la investigación sobre liderazgo educativo. Particularmente, nos centramos en tres grandes dimensiones actuales de la investigación sobre el liderazgo: el liderazgo pedagógico o para el aprendizaje, el liderazgo distribuido y el liderazgo para la justicia social. A su vez, estas dimensiones constituyen el interés principal de cada uno de los tres proyectos “vivos” del Plan Nacional de I+D+i que dirigen respectivamente los autores del artículo. La comprensión actual del liderazgo se aleja de la visión del director como único agente con poder, para adoptar una perspectiva distribuida o compartida. A su vez, se busca un liderazgo pedagógico capaz de incidir en la mejora de los aprendizajes, creando condiciones para que el profesorado pueda hacerlo mejor. Y también, por último, un liderazgo para la justicia social, que asegure una buena educación a todos los alumnos, desde una perspectiva inclusiva y equitativa. Con el propósito de mantener conectadas dichas perspectivas, los autores del artículo han formado recientemente la “Red de Investigación sobre Liderazgo y Mejora Educativa (RILME)”.As most of top-bottom educational reforms have proved very limited impact on school improvement, educational leadership is increasingly perceived as the key factor to promote such improvement, facilitating the conditions that can lead us towards more successful schools. Departing from a review of the current international literature, this paper suggests and discusses three of the relevant focus of the research about educational leadership, including: leadership for learning, distributed leadership, and leadership for social justice. Such dimensions are respectively the core interest of each of the three current research projects (funded by the National R&D&I Plan) led by the authors of the paper. On the one hand, the current understanding of leadership is far from the vision of the principal as the only agent that exerts power and influence in the school and close to a shared o distributed perspective. On the other hand, only instructional leadership will be capable to improve learning, building conditions for teachers to improve their teaching. Finally, schools need a leadership for social justice in order to ensure a good education to all students, from an inclusive and equitable perspective. Bearing in mind the purpose of getting connected such perspectives, the authors of the article have recently launched the “Network of Research on Leadership and School Improvement”
Effect of ß-cyclodextrin on phospholipids and cholesterol of the milk fat globule membrane
The aim of this study was to evaluate the effect of ß-cyclodextrin (ß-CD) on phospholipids and cholesterol in raw pasteurized milk with the purpuse on removal cholesterol from the milk fat. Total phospholipids decrease slightly in ß-CD treated milk but were not signinificantly affected by the effect of the ß-CD. ß-CD is an effective oligosacharide for cholesterol removal from milk with more than 97% of reduction and does not affect significantly the individual phospholipids (phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, phosphatidylinositol and phosphatidylserina) of the milk fat globule membrane.The authors thanks to the Ministry of Economy and Competitiveness from Spain (grant number AGL-2011-26713).Peer Reviewe
On the origin of the jet-like radio/X-ray morphology of G290.1-0.8
The origin and evolution of supernova remnants of the mixed-morphology class
is not well understood. Several remnants present distorted radio or X-ray
shells with jet-like structures. G290.1-0.8 (MSH 11-61A) belongs to this class.
We aim to investigate the nature of this supernova remnant in order to unveil
the origin of its particular morphology. We based our work on the study of the
X-ray emitting plasma properties and the conditions imposed by the cold
interstellar medium where the remnant expanded. We use archival radio, HI line
data and X-ray observations from XMM-Newton and Chandra observatories, to study
G290.1-0.8 and its surrounding medium. Spatially resolved spectral analysis and
mean photon energy maps are used to obtain physical and geometrical parameters
of the source. Radio continuum and HI line maps give crucial information to
understand the radio/X-ray morphology. The X-ray images show that the remnant
presents two opposite symmetric bright spots on a symmetry axis running towards
the NW-SE direction. Spectral analysis and mean photon energy maps confirm that
the physical conditions of the emitting plasma are not homogeneous throughout
the remnant. In fact, both bright spots have higher temperatures than the rest
of the plasma and its constituents have not reached ionization equilibrium yet.
HI line data reveal low density tube-like structures aligned along the same
direction. This evidence supports the idea that the particular X-ray morphology
observed is a direct consequence of the structure of the interstellar medium
where the remnant evolved. However, the possibility that an undetected
point-like object, as a neutron star, exists within the remnant and contributes
to the X-ray emission cannot be discarded. Finally, we suggest that a supernova
explosion due to the collapse of a high-mass star with a strong bipolar wind
can explain the supernova remnant morphology.Comment: 8 pages, 6 figures. Accepted for publication in A&
Capacity Limits of Spectrum-Sharing in Hoyt (Nakagami-q) Fading Channels
A channel capacity analysis is presented in this work for a spectrum-sharing cognitive radio link in which the fading experienced by the signal is modeled with the Hoyt (Nakagami-q) distribution. Based on a novel formulation of the squared Hoyt distribution derived by the authors, simple expressions for the capacity of the secondary link in a number of scenarios of interest are derived, which are given in terms of easy-to-compute finite-range integrals of elementary functions. The effect of fading severity in the secondary transmitter-primary receiver (ST-PR) and secondary transmitter-secondary receiver (ST-SR) links, and the impact of different antenna gains on the system performance are analyzed. We show that in the presence of severe fading for the ST-PR link, the capacity of the ST-SR link is increased.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. MINECO. Fondos FEDER. European Union Marie-Curie COFUND U-mobility program
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