573 research outputs found

    Large time wellposdness to the 3-D Capillary-Gravity Waves in the long wave regime

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    In the regime of weakly transverse long waves, given long-wave initial data, we prove that the nondimensionalized water wave system in an infinite strip under influence of gravity and surface tension on the upper free interface has a unique solution on [0,{T}/\eps] for some \eps independent of constant T.T. We shall prove in the subsequent paper \cite{MZZ2} that on the same time interval, these solutions can be accurately approximated by sums of solutions of two decoupled Kadomtsev-Petviashvili (KP) equations.Comment: Split the original paper(The long wave approximation to the 3-D capillary-gravity waves) into two parts, this is the first on

    Linear Estimation of Location and Scale Parameters Using Partial Maxima

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    Consider an i.i.d. sample X^*_1,X^*_2,...,X^*_n from a location-scale family, and assume that the only available observations consist of the partial maxima (or minima)sequence, X^*_{1:1},X^*_{2:2},...,X^*_{n:n}, where X^*_{j:j}=max{X^*_1,...,X^*_j}. This kind of truncation appears in several circumstances, including best performances in athletics events. In the case of partial maxima, the form of the BLUEs (best linear unbiased estimators) is quite similar to the form of the well-known Lloyd's (1952, Least-squares estimation of location and scale parameters using order statistics, Biometrika, vol. 39, pp. 88-95) BLUEs, based on (the sufficient sample of) order statistics, but, in contrast to the classical case, their consistency is no longer obvious. The present paper is mainly concerned with the scale parameter, showing that the variance of the partial maxima BLUE is at most of order O(1/log n), for a wide class of distributions.Comment: This article is devoted to the memory of my six-years-old, little daughter, Dionyssia, who leaved us on August 25, 2010, at Cephalonia isl. (26 pages, to appear in Metrika

    Large time existence for 3D water-waves and asymptotics

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    We rigorously justify in 3D the main asymptotic models used in coastal oceanography, including: shallow-water equations, Boussinesq systems, Kadomtsev-Petviashvili (KP) approximation, Green-Naghdi equations, Serre approximation and full-dispersion model. We first introduce a ``variable'' nondimensionalized version of the water-waves equations which vary from shallow to deep water, and which involves four dimensionless parameters. Using a nonlocal energy adapted to the equations, we can prove a well-posedness theorem, uniformly with respect to all the parameters. Its validity ranges therefore from shallow to deep-water, from small to large surface and bottom variations, and from fully to weakly transverse waves. The physical regimes corresponding to the aforementioned models can therefore be studied as particular cases; it turns out that the existence time and the energy bounds given by the theorem are always those needed to justify the asymptotic models. We can therefore derive and justify them in a systematic way.Comment: Revised version of arXiv:math.AP/0702015 (notations simplified and remarks added) To appear in Inventione

    Near-complete genome sequencing of swine vesicular disease virus using the Roche GS FLX sequencing platform

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    Swine vesicular disease virus (SVDV) is an enterovirus that is both genetically and antigenically closely related to human coxsackievirus B5 within the Picornaviridae family. SVDV is the causative agent of a highly contagious (though rarely fatal) vesicular disease in pigs. We report a rapid method that is suitable for sequencing the complete protein-encoding sequences of SVDV isolates in which the RNA is relatively intact. The approach couples a single PCR amplification reaction, using only a single PCR primer set to amplify the near-complete SVDV genome, with deep-sequencing using a small fraction of the capacity of a Roche GS FLX sequencing platform. Sequences were initially verified through one of two criteria; either a match between a de novo assembly and a reference mapping, or a match between all of five different reference mappings performed against a fixed set of starting reference genomes with significant genetic distances within the same species of viruses. All reference mappings used an iterative method to avoid bias. Further verification was achieved through phylogenetic analysis against published SVDV genomes and additional Enterovirus B sequences. This approach allows high confidence in the obtained consensus sequences, as well as provides sufficiently high and evenly dispersed sequence coverage to allow future studies of intra-host variation

    The Value of Protocol Biopsies to Identify Patients With De Novo Donorâ Specific Antibody at High Risk for Allograft Loss

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137430/1/ajt14161_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137430/2/ajt14161-sup-0001-TableS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137430/3/ajt14161.pd

    Divergent drivers of leaf trait variation within species, among species, and among functional groups

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    Understanding variation in leaf functional traits—including rates of photosynthesis and respiration and concentrations of nitrogen and phosphorus—is a fundamental challenge in plant ecophysiology. When expressed per unit leaf area, these traits typically increase with leaf mass per area (LMA) within species but are roughly independent of LMA across the global flora. LMA is determined by mass components with different biological functions, including photosynthetic mass that largely determines metabolic rates and contains most nitrogen and phosphorus, and structural mass that affects toughness and leaf lifespan (LL). A possible explanation for the contrasting trait relationships is that most LMA variation within species is associated with variation in photosynthetic mass, whereas most LMA variation across the global flora is associated with variation in structural mass. This hypothesis leads to the predictions that (i) gas exchange rates and nutrient concentrations per unit leaf area should increase strongly with LMA across species assemblages with low LL variance but should increase weakly with LMA across species assemblages with high LL variance and that (ii) controlling for LL variation should increase the strength of the above LMA relationships. We present analyses of intra- and interspecific trait variation from three tropical forest sites and interspecific analyses within functional groups in a global dataset that are consistent with the above predictions. Our analysis suggests that the qualitatively different trait relationships exhibited by different leaf assemblages can be understood by considering the degree to which photosynthetic and structural mass components contribute to LMA variation in a given assemblage

    A Rigorous Justification of the Modulation Approximation to the 2D Full Water Wave Problem

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    We consider the 2D inviscid incompressible irrotational infinite depth water wave problem neglecting surface tension. Given wave packet initial data, we show that the modulation of the solution is a profile traveling at group velocity and governed by a focusing cubic nonlinear Schrodinger equation, with rigorous error estimates in Sobolev spaces. As a consequence, we establish existence of solutions of the water wave problem in Sobolev spaces for times in the NLS regime provided the initial data is suitably close to a wave packet of sufficiently small amplitude in Sobolev spaces

    Palcayaco watershed management through environmental zoning in Huancavelica, Peru

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    The technical and integrated participation of the population in environmental zoning and soil and water conservation techniques and management is a sustainable alternative for watershed management. The objective of the research was to develop an environmental zoning map for the Palcayaco watershed in Huancavelica, Peru (from its socioeconomic aspects to its technical recommendations). The research work was deductive, where all the necessary data were delimited, described, inventoried, recapitulated and extracted to describe the morphometric parameters, biophysical and socioeconomic situation, environmental zoning and techniques for soil and water conservation. Results: the watershed was perennial, an average slope of 29.65%, a time of concentration of 180.6 min and a balanced hypsometric curve type (B). It also had low population density, unpaved roads, scarce basic services, and poor education and health services infrastructure. The watershed presented different ecoregions, life zones, climatic classification and altitudinal sector, current land use for agricultural, livestock and silvopastoral production, steep type, forest pasture use and protection capacity. The conflict area was in good use, and economic-ecological zoning was in protection, conservation, recovery, water, productive, and urban-industrial. The environmental zoning designed for the Palcayaco watershed preserved the most important natural resources for rural communities, improving their biophysical and socioeconomic status. Through soil and water conservation techniques and management, it will prevent the degradation of the watershed for a better and sustainable future.             
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