Search results for "Linea"
showing 10 items of 7724 documents
Parabolic equations with nonlinear singularities
2011
Abstract We show the existence of positive solutions u ∈ L 2 ( 0 , T ; H 0 1 ( Ω ) ) for nonlinear parabolic problems with singular lower order terms of the asymptote-type. More precisely, we shall consider both semilinear problems whose model is { u t − Δ u + u 1 − u = f ( x , t ) in Ω × ( 0 , T ) , u ( x , 0 ) = u 0 ( x ) in Ω , u ( x , t ) = 0 on ∂ Ω × ( 0 , T ) , and quasilinear problems having natural growth with respect to the gradient, whose model is { u t − Δ u + ∣ ∇ u ∣ 2 u γ = f ( x , t ) in Ω × ( 0 , T ) , u ( x , 0 ) = u 0 ( x ) in Ω , u ( x , t ) = 0 on ∂ Ω × ( 0 , T ) , with γ > 0 . Moreover, we prove a comparison principle and, as an application, we study the asymptotic behav…
Manifestaciones orales de la enfermedad por depósito lineal de IgA
2004
La enfermedad por depósito lineal de IgA o enfermedad IgA lineal (EAL) es un proceso mucocutaneo crónico e infrecuente de origen autoinmune, caracterizado por depósitos lineales de IgA a lo largo de la membrana basal. En la mayor parte de los casos, junto a las lesiones cutáneas, aparecen lesiones orales y en otras mucosas. Se han descrito casos en los que la afectación se limitaba a la mucosa oral. Por ello es importante el conocimiento de esta patología a la hora de establecer el diagnóstico diferencial de las enfermedades mucocutaneas ampollares. En esta revisión se analizan los principales aspectos clinicopatológicos de esta enfermedad, haciendo un hincapié especial en las manifestacion…
On the accuracy of three statistical softwares
2005
In this paper we compare the accuracy of three packages that are commonly used for statistical calculations: Excel of Microsoft, version XP Edition 2003, Statistica of Statsoft, version 6, and R, an open-source free software, available on the web, version 1.9.0. To assess the accuracy of each software in different statistical areas, we are going to use benchmarks expressly developed for this aim. The obtained results show a superiority of R in comparison with the other two softwares.
Study of supersymmetric signals with R-parity violation in ATLAS at LHC
2013
219 páginas. Tesis Doctoral del Departamento de Física Atómica, Molecular y Nuclear, de la Universidad de Valencia.
Über gemischte bindungen in der IV. hauptgruppe
1987
Abstract Reaction of Ph3SnLi with Ph2SiCl2 or Ph2GeCl2 at −78°C in THF yields (Ph3Sn)2SiPh2 (1) and (Ph3Sn)2GePh2 (2). The crystal structure of 1 (R = 0.075) exhibits SnSi distances of 257.2(4) and 257.9(5) pm, an SnSiSn angle of 118.5(2)°, and a central C3SnSiC2SnC3 molecular skeleton with symmetry close to C2. The geminal NMR coupling 2J(119Sn ⋯ 119Sn) in 1, and in a tri-, tetra- and pentastannane series shows a linear correlation to their respective non-bonded d(Sn ⋯ Sn) distances (I(t-Bu2Sn)4I: 20 Hz/496 pm; 1: 724 Hz/443 pm).
Authentication of the protected designation of origin horchata de Valencia through the chemometric treatment of mineral content
2010
Spanish horchata de chufa samples were authenticated based on the determination of mineral elements by inductively coupled plasma atomic emission spectrometry (ICP-OES) combined with different chemometric methods. The ability of multivariate analysis, such as principle components analysis (PCA), classification and regression trees (CARTs) and discriminant analysis (DA) were evaluated in order to achieve a correct sample classification. It was possible to clearly differentiate homemade and long-life commercial samples by all three methods and CART and DA provided an excellent tool to establish the growth origin of the tiger nuts. CART analysis employed the concentration of Mg to discriminate…
Global linear feedback control for the generalized Lorenz system
2006
Abstract In this paper we show how the chaotic behavior of the Chen system can be controlled via feedback technique. We design both a nonlinear feedback controller and a linear one which globally regulate the closed-loop system states to a given point. We finally show that our approach works also for the whole family of the generalized Lorenz system.
L'arbre de la vie a-t-il une structure fractale?
1999
Abstract We analyse the time sequences of major evolutionary leaps at various scales, from the scale of the global tree of life, to the scales of orders and families such as sauropod dinosaurs, North American fossil Equidae, rodents, and primates including the Hominidae. In each case we find that these data are consistent with a log- periodic law to high level of statistical significance. Such a law is characterized by a critical epoch of convergence Tc specific to the lineage under consideration and that can be interpreted as the end of that lineage's capacity to evolve.
Complete phylogeny and historical biogeography of true rosefinches (Aves:Carpodacus)
2013
True rosefinches (Aves: Carpodacus) are restricted to Eurasia, and 19 out of 25 species occur in the Sino-Himalayas, making this the likely centre of origin. To test this hypothesis, suggested species splits had to be evaluated and potential further cryptic diversity unravelled. A taxon-complete dated molecular phylogeny was reconstructed using maximum-likelihood and Bayesian methods. Maximum-parsimony and likelihood approaches were applied to deduce ancestral areas. Rosefinches, including the widespread Carpodacus erythrinus (Pallas, 1770), originated in south-west China (and the Himalayas) 14 Mya, and gave rise to a smaller clade consisting of C. erythrinus, Haematospiza sipahi (Hodgson, …
The CD38-Positive and CD38-Negative Subsets of CD34(high)-Positive Primary Acute Myeloid Leukemia Blasts Differ Considerably in the Expression of Imm…
2008
Abstract Acute myeloid leukemia (AML) is thought to arise from a rare putative ‘leukemic stem cell’ that is capable of self-renewal and formation of leukemic blasts. Serial xenotransplantation studies in immunodeficient mice have shown that this leukemia-initiating cell resides at very low numbers within CD34(high)-positive CD38-negative AML cells. Thus, immunotherapeutic approaches successfully eradicating this cell compartment should result in cure from disease. The objective of our study was to characterize the immune phenotype of the CD38-negative and CD38-positive subsets of primary CD34(high)-positive AML blasts ex vivo. We obtained therapeutic leukapheresis products from 17 AML patie…