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Sample records for chile taxonomic covariation

  1. Phylogenetic evaluation of taxonomic definition of didelphid mouse opossum of the genus Thylamys from valleys of Coquimbo region, Chile.

    Science.gov (United States)

    Boric-Bargetto, Dusan; Zúñiga-Reinoso, Álvaro; Cancino, Ricardo A; González-Acuña, Daniel; Rodríguez-Serrano, Enrique; Palma, R Eduardo; Hernández, Cristián E

    2016-04-21

    Only two species of Didelphidae are currently recognized in Chile, the sister species Thylamys elegans, endemic of Mediterranean ecorregion and Thylamys pallidior, the inhabitant of the Puna and desert canyons. Three subspecies have been described for T. elegans: T. e. elegans, T. e. coquimbensis and T. e. soricinus. However, a recent study based on morphological analyses, synonymized T. elegans coquimbensis from the Coquimbo valleys (30-31° S) with T. pallidior and proposed that T. elegans and T. pallidior could be in sympatry at Coquimbo valleys between Fray Jorge (30°40'S) and Paiguano (30°02' S). We assess the current definition of T. e. coquimbensis and T. e. elegans, as well as this taxonomical conflict among the mouse opossums from the Coquimbo valleys through phylogenetic analyses of cytochrome b mitochondrial gene sequences. In this study, for the first time, we used specimens from the type localities of T. e. coquimbensis and T. e. elegans. In addition, we analyzed diagnostic cranial structures for this taxonomic revision. The results supported two allopatric clades, allowing us to keep the taxonomic definition of T. e. elegans and T. e. coquimbensis as phylogenetic reciprocal monophyletic clades and polyphyletic with T. pallidior. This result corroborates previous morphological analyses, which support that mouse opossums from the Coquimbo valleys are T. e. coquimbensis, thus extending its geographic distribution to the coast of Coquimbo and Atacama regions. We don´t have evidence for sympatric distribution between T. elegans and T. pallidior in the Coquimbo region.

  2. A taxonomic review of the Pterophoridae (Lepidoptera) from Argentina and Chile

    NARCIS (Netherlands)

    Gielis, C.

    1991-01-01

    The known species of Pterophoridae occurring in Argentina and Chile are reviewed. Nearly all the available type specimens of species occurring in the area have been examined and five new synonyms have been established. Some primary types are considered to be lost. In this paper three new genera and

  3. Chile.

    Science.gov (United States)

    1988-09-01

    Chile is a long (2650 miles), narrow (250 miles at widest point) country sandwiched between the Andes mountains and the Pacific. The northern desert is rich in copper and nitrates; the temperate middle region is agricultural and supports the major cities, including Santiago, the capital, and the port of Valparaiso; and the southern region is a cold and damp area of forests, grasslands, lakes, and fjords. The country is divided into 12 administrative regions. Chile's population of 12.5 million are mainly of Spanish or Indian descent or mestizos. Literacy is 92.3%, and the national language is Spanish. Infant mortality is 18.1/1000, and life expectancy is 68.2 years. 82% of the people are urban, and most are Roman Catholics. Chile was settled by the Spanish in 1541 and attached to the Viceroyalty of Peru. Independence was won in 1818 under the leadership of Bernardo O'Higgins. In the 1880s Chile extended its sovereignty over the Strait of Magellan in the south and areas of southern Peru and Bolivia in the north. An officially parliamentary government, elected by universal suffrage, drifted into oligarchy and finally into a military dictatorship under Carlos Ibanez in 1924. Constitutional government was restored in 1932. The Christian Democratic government of Eduardo Frei (1964-70) inaugurated major reforms, including land redistribution, education, and far-reaching social and economic policies. A Marxist government under Salvador Allende lasted from 1970 to 1973 when the present military government of General Pinochet Ugarte took power, overthrew Allende, abolished the Congress, and banned political parties. It has moved the country in the direction of a free market economy but at the cost of systematic violations of human rights. A new constitution was promulgated in 1981, and congressional elections have been scheduled for October, 1989. A "National Accord for Transition to Full Democracy" was mediated by the Catholic Church in 1985. The social reforms of the

  4. Taxonomy and biology of a new Oecophoridae (Lepidoptera from central Chile Taxonomía y biología de un nuevo Oecophoridae (Lepidoptera de Chile central

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    T. HEATH-OGDEN

    2001-09-01

    Full Text Available The adult, larva, and pupa of Afdera jimenae Ogden & Parra sp. nov. are described and illustrated. Larvae live in leaf litter throughout all instars and are generalists feeding upon the fallen leaves of a number of different plant species of sclerophyllous forests. Comments on morphological details and bionomics of this species are given. This is the second species of Afdera know for ChileSe describe e ilustra el adulto, larva y pupa de Afdera jimenae Ogden & Parra sp. nov. Los diferentes estados larvarios se encuentran en la hojarasca del bosque esclerófilo de la Península de Hualpén, alimentándose de hojas en descomposición de diferentes especies vegetales. Se entregan comentarios sobre detalles morfológicos y bionómicos de la especie. Esta es la segunda especie de Afdera descrita para Chile

  5. Taxonomic Treatment of Solanum Section Petota (Wild Potatoes) in Catálogo de Plantas Vasculares del Cono Sur (Argentina, Chile, Paraguay, Uruguay, y sur del Brasil)

    Science.gov (United States)

    Solanum section Petota (Solanaceae), which includes the cultivated potato (Solanum tuberosum) and its wild relatives, contains over 150 wild species distributed from the southwestern U.S.A. (38°N) to central Argentina and adjacent Chile (41°S). This catalog includes all species from the Southern Con...

  6. Claves para el reconocimiento taxonómico dentario en taxa del Superorden Squalomorphi de Chile (Chondrichthyes: Elasmobranchii Taxonomic dental keys for the Chilean taxa of the Superorder Squalomorphi (Chondricthyes: Elasmobranchii

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    Sylvia Sáez

    2010-01-01

    Full Text Available Se presenta una serie de claves para el reconocimiento dentario de diferentes taxa del Superorden Squalomorphi de Chile. Se seleccionaron características dentarias externas que permitan obtener una observación más expedita que conduzcan a un estudio más acabado, de la diagnosis de los diferentes taxa constituyentes de este grupo de peces, haciéndolas extensibles para estudios de piezas dentales fósiles.A series of taxonomic dental keys is presented for the Chilean taxa of the Superorder Squalomorphi. External dental characteristics were selected for easier observation, leading to more thorough studies. This allows diagnoses of the different taxa comprising this group of fishes and, moreover, can be extended to studies of fossil teeth.

  7. Claves taxonómicas para el reconocimiento dentario en taxa del superorden Rajomorphii de Chile (Chondrichthyes, Batoidea Taxonomic dental keys for the Chilean taxa of the superorder Rajomorphii (Chondrichthyes, Batoidea

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    Sylvia Sáez

    2012-07-01

    Full Text Available Se presenta claves taxonómicas basadas en características morfológicas dentarias externas e internas, que permiten el reconocimiento de cada orden, familia y género de los batoídeos conocidos en Chile. En algunos casos, como en las familias Rhinobatidae, Torpedinidae, Narcinidae, Myliobatidae, Mobulidae, Dasyatidae y Urotrygonidae, las claves permiten el reconocimiento específico pero, en otros casos, sólo se puede discriminar hasta género, dadas las limitaciones impuestas por los conocimientos existentes. Estas claves son una herramienta complementaria a la diagnosis de rayas y están orientadas al reconocimiento de fragmentos dentales, hallazgos paleontológicos de dientes así como para las piezas dentales asociadas con la mandíbula. De esta manera, se entrega un apoyo taxonómico nuevo con características dentales diferentes a las consideradas actualmente para este superorden.A series of keys with external and internal dental morphologic features for the identification of each order, family and genus of rays and skates of the batoids known in Chile, are presented. In the case of families Rhinobatidae, Torpedinidae, Narcinidae, Myliobatidae, Mobulidae, Dasyatidae and Urotrygonidae, an identification at the species level is possible. In other cases, due to limitations imposed by the existing knowledge, only discrimination up to genus is allowed. These keys are a complementary tool for the diagnosis of rays suitable for the identification of dental fragments, paleontological discoveries of teeth as well as for jaw teeth. This tool offers a novel taxonomic support, which includes dental features different from those considered nowadays for this superorder.

  8. La Familia Trochidae (Mollusca: Gastropoda en el norte de Chile: consideraciones ecológicas y taxonómicas The trochidae family (Mollusca : Gastropoda in northern Chile: taxonomic and ecological considerations

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    DAVID VELIZ

    2000-12-01

    Full Text Available Este estudio describe la diversidad, y la distribución latitudinal y batimétrica de los caracoles de la Familia Trochidae en el norte de Chile, mediante muestreos intermareales y submareales someros, realizados entre 1996 y 1999 entre Arica (18º S y Los Vilos (31º S, y de muestras de profundidad provenientes de la pesca de arrastre del camarón nylon, Heterocarpus reedi. En el norte de Chile, la Familia Trochidae está representada por cuatro géneros: Tegula y Diloma de distribución intermareal y submareal somero hasta los 20 m de profundidad, y Bathybembix y Calliostoma presentes en profundidades superiores a los 200 m. El género Tegula tiene seis especies (T. quadricostata, T. luctuosa, T. ignota, T. atra, T. tridentata y T. euryomphala distribuídas en sustratos rocosos intermareales y submarales someros. El género Diloma está representado por una especie, D. nigerrima, de distribución intermareal hasta pocos metros de profundidad. El género Calliostoma tiene dos especies C. chilena y C. delli, las que se distribuyen entre 200 y 750 m de profundidad. Finalmente, el género Bathybembix está representado por B. humboldti y B. macdonaldi distribuídas entre 200 y 1480 m de profundidad. Esta segregación batimétrica parece estar relacionada a las estrategias alimentarias de cada uno de los géneros de la familia Trochidae. Diloma y Tegula son herbívoros, las especies del género Bathybembix son alimentadoras de depósito y las de Calliostoma son carnívorasThis study reveals the diversity, and the bathimetric and latitudinal distribution of the snails of the Trochidae family members in northern Chile, throughout the analysis of all Trochidae gastropods entailed in intertidal and subtidal (from the `camarón naylon' fishery samples collected during 1996 and 1999 between Arica (ca 18º S and Los Vilos (ca 31º S. The Trochidae family in northern Chile have four genus: Tegula and Diloma that are distributed on intertidal and shallow

  9. La fauna de caprélidos (Crustacea: Amphipoda: Caprellidea de la costa de Coquimbo, centro-norte de Chile, con una clave taxonómica para la identificación de las especies The caprellid fauna (Crustacea: Amphipoda: Caprellidea from the coast of Coquimbo, Northern-central Chile, with a taxonomic key for species identification

    Directory of Open Access Journals (Sweden)

    JOSÉ M. GUERRA-GARCÍA

    2001-12-01

    difficult due to the high degree of intra-specific morphological variability and the fact that literature and specimens from Museums are not easily located. The objective of the present study was to provide the taxonomical tools to identify the most common caprellid species from northern-central Chile. Several habitats were examined (buoys, boulders, algal/seagrass beds and six caprellid species were found: Caprellina longicollis (Nicolet, 1849, Caprella equilibra Say, 1818, C. scaura Templeton, 1836, C. verrucosa Boeck, 1871; Deutella venenosa Mayer, 1890 and Paracaprella pusilla Mayer, 1890. Caprella scaura, C. verrucosa and D. venenosa were most abundant among algae, hydrozoans and bryozoans growing on buoys. Caprella equilibra, also present on buoys, was most abundant underneath boulders in exposed rocky intertidal zones, where additionally D. venenosa and P. pusilla were found. Caprella scaura was dominant in plant beds above sandy subtidal bottom, especially among the alga Gracilaria chilensis and the seagrass Heterozostera tasmanica, where it occurred together with Caprellina longicollis. Paracaprella pusilla represents a new citation for the pacific coasts of S-America, being a new record for Chile. The species D. venenosa, which was recorded for the first time since the original description by Mayer in the year 1890, is considered an endemic species from the central coast of Chile

  10. Preserving Chile

    OpenAIRE

    Brennand, Charlotte P.

    2010-01-01

    The best way to preserve chile depends on how you plan to use it and your available storage space. Frozen or canned chile is best for chile rellenos and salsas. Stews can use frozen, canned or dried chile. Dried chile has minimal storage requirements and is light-weight for taking on camping trips. Pickled chiles can be used on a relish plate or as an ingredient in other dishes.

  11. Estimating Cosmological Parameter Covariance

    CERN Document Server

    Taylor, Andy

    2014-01-01

    We investigate the bias and error in estimates of the cosmological parameter covariance matrix, due to sampling or modelling the data covariance matrix, for likelihood width and peak scatter estimators. We show that these estimators do not coincide unless the data covariance is exactly known. For sampled data covariances, with Gaussian distributed data and parameters, the parameter covariance matrix estimated from the width of the likelihood has a Wishart distribution, from which we derive the mean and covariance. This mean is biased and we propose an unbiased estimator of the parameter covariance matrix. Comparing our analytic results to a numerical Wishart sampler of the data covariance matrix we find excellent agreement. An accurate ansatz for the mean parameter covariance for the peak scatter estimator is found, and we fit its covariance to our numerical analysis. The mean is again biased and we propose an unbiased estimator for the peak parameter covariance. For sampled data covariances the width estimat...

  12. Manifestly covariant electromagnetism

    Energy Technology Data Exchange (ETDEWEB)

    Hillion, P. [Institut Henri Poincare' , Le Vesinet (France)

    1999-03-01

    The conventional relativistic formulation of electromagnetism is covariant under the full Lorentz group. But relativity requires covariance only under the proper Lorentz group and the authors present here the formalism covariant under the complex rotation group isomorphic to the proper Lorentz group. The authors discuss successively Maxwell's equations, constitutive relations and potential functions. A comparison is made with the usual formulation.

  13. Diversidad de la familia Carabidae (Coleoptera en Chile Diversity of the family Carabidae (Coleoptera in Chile

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    SERGIO ROIG-JUÑENT

    2001-09-01

    Full Text Available Carabidae constituye dentro de los coléopteros chilenos, la cuarta familia en importancia por su cantidad de especies. El presente trabajo incluye una breve compilación acerca de la historia de la familia y de las primeras expediciones realizadas en Chile. También se realizan comparaciones de la diversidad de carábidos chilenos con respecto a otros países y el Neotrópico. Para Chile, se conocen 21 tribus, con 95 géneros y 365 especies, que representan el 38,8, 28,8 y 7,9 % de la fauna del Neotrópico, respectivamente. Chile posee un bajo número de tribus comparado con otros países, sin embargo, constituye un área importante por la presencia de seis tribus relictuales, principalmente pangeicas o gondwánicas. Chile posee 18 géneros endémicos (18,5 % de su fauna de Carabidae, 28 cuya distribución está restringida a Chile y Argentina y seis restringidos a Chile, Argentina y Uruguay. La cantidad de especies presentes en Chile es inferior a la que poseen otros países de América del Sur, pero la cantidad de especies endémicas es muy alta (204 y representa el 55,8 % de su fauna de carábidos. El alto grado de endemismo que posee Chile con respecto a otros países de América del Sur puede deberse a su condición de aislamiento, siendo las barreras más importantes la región desértica del norte y la cordillera de Los Andes. Este hecho también se vislumbra por la ausencia de importantes tribus neotropicales como Galeritini, Scaritini y Brachinini. También se incluyen en este trabajo claves para la identificación de todas las tribus y géneros presentes en Chile, como así también una breve descripción acerca de la diversidad y ambientes en los que se encuentra cada géneroThe family Carabidae is the fourth largest Coleoptera family in Chile. The present work includes a brief compilation on the taxonomic history of the family and the first expeditions to Chile. In addition, knowledge of carabid diversity in Chile is compared with

  14. Some notes on taxonomic methodology

    NARCIS (Netherlands)

    Hammen, van der L.

    1986-01-01

    The present paper constitutes an introduction to taxonomic methodology. After an analysis of taxonomic practice, and a brief survey of kinds of attributes, the paper deals with observation, description, comparison, arrangement and classification, hypothesis construction, deduction, model, experiment

  15. Covariant Hamiltonian field theory

    CERN Document Server

    Giachetta, G; Sardanashvily, G

    1999-01-01

    We study the relationship between the equations of first order Lagrangian field theory on fiber bundles and the covariant Hamilton equations on the finite-dimensional polysymplectic phase space of covariant Hamiltonian field theory. The main peculiarity of these Hamilton equations lies in the fact that, for degenerate systems, they contain additional gauge fixing conditions. We develop the BRST extension of the covariant Hamiltonian formalism, characterized by a Lie superalgebra of BRST and anti-BRST symmetries.

  16. Registro nuevo de Amphipyrinae en Chile A new record of Amphipyrinae from Chile

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    Tania S. Olivares

    2006-12-01

    Full Text Available Se registra por primera vez en Chile la especie Agrotisia subhyalina Hampson, entre las latitudes 18° 29' S 70° 20' O hasta 29° 54' S 71° 16' O (I-IV regiones en Chile. Se redescriben los genitales del macho y de la hembra y se presentan algunos aspectos taxonómicos de la especie.The species Agrotisia subhyalina Hampson is recorded for the first time from Chile (18° 29' S 70° 20' W to 29° 54' S 71° 16' W, I to IV Chilean regions. Redescriptions of male and female are presented, along with some taxonomic aspects of the species.

  17. Taxonomic abstraction in psychobiology.

    Science.gov (United States)

    Evans, S H; Chafetz, M D; Gage, F H

    1984-10-01

    If a body of knowledge in a scientific discipline is to be extended beyond empirical observation and into the realm of laws and principles, one of the fundamental requirements is a taxonomy which supports the systematic integration of observations. Psychobiology benefits from taxonomies provided by biology and chemistry, which include not only object oriented taxonomies such as species or chemical elements, but also process oriented taxonomies, such as oxidation, metabolism, phototaxis, or predation. Psychobiology has yet to provide equivalent taxonomies for its behavioral observations, although the common use of terms such as fear, anger, arousal, stress, and memory might lead one to suppose that these are based on a well established taxonomy of behavioral measures. In this report the logical and quantitative requirements for treating behavioral measures in terms of taxonomic classes are reviewed. A sample of studies representing recent research in psychobiology was examined to assess interest in such a taxonomy and to identify elements of current practice which might contribute to its development. Recent practice displays some evidence of interest in behavioral classes, in choice of language, and in frequent use of multiple dependent measures. Multivariate methods, which might elicit from such data evidence contributing to the development of a taxonomy, are rarely used. Recommendations are given on some appropriate analytic methods for data resulting from current practice and for new exploratory paradigms which could aim directly at the establishment of taxonomic classes for behaviors.

  18. Covariance mapping techniques

    Science.gov (United States)

    Frasinski, Leszek J.

    2016-08-01

    Recent technological advances in the generation of intense femtosecond pulses have made covariance mapping an attractive analytical technique. The laser pulses available are so intense that often thousands of ionisation and Coulomb explosion events will occur within each pulse. To understand the physics of these processes the photoelectrons and photoions need to be correlated, and covariance mapping is well suited for operating at the high counting rates of these laser sources. Partial covariance is particularly useful in experiments with x-ray free electron lasers, because it is capable of suppressing pulse fluctuation effects. A variety of covariance mapping methods is described: simple, partial (single- and multi-parameter), sliced, contingent and multi-dimensional. The relationship to coincidence techniques is discussed. Covariance mapping has been used in many areas of science and technology: inner-shell excitation and Auger decay, multiphoton and multielectron ionisation, time-of-flight and angle-resolved spectrometry, infrared spectroscopy, nuclear magnetic resonance imaging, stimulated Raman scattering, directional gamma ray sensing, welding diagnostics and brain connectivity studies (connectomics). This review gives practical advice for implementing the technique and interpreting the results, including its limitations and instrumental constraints. It also summarises recent theoretical studies, highlights unsolved problems and outlines a personal view on the most promising research directions.

  19. Covariant Bardeen perturbation formalism

    Science.gov (United States)

    Vitenti, S. D. P.; Falciano, F. T.; Pinto-Neto, N.

    2014-05-01

    In a previous work we obtained a set of necessary conditions for the linear approximation in cosmology. Here we discuss the relations of this approach with the so-called covariant perturbations. It is often argued in the literature that one of the main advantages of the covariant approach to describe cosmological perturbations is that the Bardeen formalism is coordinate dependent. In this paper we will reformulate the Bardeen approach in a completely covariant manner. For that, we introduce the notion of pure and mixed tensors, which yields an adequate language to treat both perturbative approaches in a common framework. We then stress that in the referred covariant approach, one necessarily introduces an additional hypersurface choice to the problem. Using our mixed and pure tensors approach, we are able to construct a one-to-one map relating the usual gauge dependence of the Bardeen formalism with the hypersurface dependence inherent to the covariant approach. Finally, through the use of this map, we define full nonlinear tensors that at first order correspond to the three known gauge invariant variables Φ, Ψ and Ξ, which are simultaneously foliation and gauge invariant. We then stress that the use of the proposed mixed tensors allows one to construct simultaneously gauge and hypersurface invariant variables at any order.

  20. Covariant canonical quantization

    Energy Technology Data Exchange (ETDEWEB)

    Hippel, G.M. von [University of Regina, Department of Physics, Regina, Saskatchewan (Canada); Wohlfarth, M.N.R. [Universitaet Hamburg, Institut fuer Theoretische Physik, Hamburg (Germany)

    2006-09-15

    We present a manifestly covariant quantization procedure based on the de Donder-Weyl Hamiltonian formulation of classical field theory. This procedure agrees with conventional canonical quantization only if the parameter space is d=1 dimensional time. In d>1 quantization requires a fundamental length scale, and any bosonic field generates a spinorial wave function, leading to the purely quantum-theoretical emergence of spinors as a byproduct. We provide a probabilistic interpretation of the wave functions for the fields, and we apply the formalism to a number of simple examples. These show that covariant canonical quantization produces both the Klein-Gordon and the Dirac equation, while also predicting the existence of discrete towers of identically charged fermions with different masses. Covariant canonical quantization can thus be understood as a ''first'' or pre-quantization within the framework of conventional QFT. (orig.)

  1. Covariant canonical quantization

    CERN Document Server

    Von Hippel, G M; Hippel, Georg M. von; Wohlfarth, Mattias N.R.

    2006-01-01

    We present a manifestly covariant quantization procedure based on the de Donder-Weyl Hamiltonian formulation of classical field theory. Covariant canonical quantization agrees with conventional canonical quantization only if the parameter space is d=1 dimensional time. In d>1 quantization requires a fundamental length scale, and any bosonic field generates a spinorial wave function, leading to the purely quantum-theoretical emergence of spinors as a byproduct. We provide a probabilistic interpretation of the wave functions for the fields, and apply the formalism to a number of simple examples. These show that covariant canonical quantization produces both the Klein-Gordon and the Dirac equation, while also predicting the existence of discrete towers of identically charged fermions with different masses.

  2. Covariance Applications with Kiwi

    Science.gov (United States)

    Mattoon, C. M.; Brown, D.; Elliott, J. B.

    2012-05-01

    The Computational Nuclear Physics group at Lawrence Livermore National Laboratory (LLNL) is developing a new tool, named `Kiwi', that is intended as an interface between the covariance data increasingly available in major nuclear reaction libraries (including ENDF and ENDL) and large-scale Uncertainty Quantification (UQ) studies. Kiwi is designed to integrate smoothly into large UQ studies, using the covariance matrix to generate multiple variations of nuclear data. The code has been tested using critical assemblies as a test case, and is being integrated into LLNL's quality assurance and benchmarking for nuclear data.

  3. Covariance Applications with Kiwi

    Directory of Open Access Journals (Sweden)

    Elliott J.B.

    2012-05-01

    Full Text Available The Computational Nuclear Physics group at Lawrence Livermore National Laboratory (LLNL is developing a new tool, named ‘Kiwi’, that is intended as an interface between the covariance data increasingly available in major nuclear reaction libraries (including ENDF and ENDL and large-scale Uncertainty Quantification (UQ studies. Kiwi is designed to integrate smoothly into large UQ studies, using the covariance matrix to generate multiple variations of nuclear data. The code has been tested using critical assemblies as a test case, and is being integrated into LLNL's quality assurance and benchmarking for nuclear data.

  4. Chile: Its Conventional Threats

    Science.gov (United States)

    2005-03-18

    Bolivia’s gas to Mexico and North America. Chile’s President Lagos likewise invited Bolivia to construct a plant in Chile to facilitate gas production at...tdf.htm>. Internet. Accessed 30 October 2004. 20 21 BIBLIOGRAPHY Barros, Van Buren Mario. Historia Diplomatica de Chile . Santiago: Editorial Andres

  5. A Taxonomic Search Engine: Federating taxonomic databases using web services

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    Page Roderic DM

    2005-03-01

    Full Text Available Abstract Background The taxonomic name of an organism is a key link between different databases that store information on that organism. However, in the absence of a single, comprehensive database of organism names, individual databases lack an easy means of checking the correctness of a name. Furthermore, the same organism may have more than one name, and the same name may apply to more than one organism. Results The Taxonomic Search Engine (TSE is a web application written in PHP that queries multiple taxonomic databases (ITIS, Index Fungorum, IPNI, NCBI, and uBIO and summarises the results in a consistent format. It supports "drill-down" queries to retrieve a specific record. The TSE can optionally suggest alternative spellings the user can try. It also acts as a Life Science Identifier (LSID authority for the source taxonomic databases, providing globally unique identifiers (and associated metadata for each name. Conclusion The Taxonomic Search Engine is available at http://darwin.zoology.gla.ac.uk/~rpage/portal/ and provides a simple demonstration of the potential of the federated approach to providing access to taxonomic names.

  6. Using Analysis of Covariance (ANCOVA) with Fallible Covariates

    Science.gov (United States)

    Culpepper, Steven Andrew; Aguinis, Herman

    2011-01-01

    Analysis of covariance (ANCOVA) is used widely in psychological research implementing nonexperimental designs. However, when covariates are fallible (i.e., measured with error), which is the norm, researchers must choose from among 3 inadequate courses of action: (a) know that the assumption that covariates are perfectly reliable is violated but…

  7. Covariantly Quantum Galileon

    CERN Document Server

    Saltas, Ippocratis D

    2016-01-01

    We derive the 1-loop effective action of the cubic Galileon coupled to quantum-gravitational fluctuations in a background and gauge-independent manner, employing the covariant framework of DeWitt and Vilkovisky. Although the bare action respects shift symmetry, the coupling to gravity induces an effective mass to the scalar, of the order of the cosmological constant, as a direct result of the non-flat field-space metric, the latter ensuring the field-reparametrization invariance of the formalism. Within a gauge-invariant regularization scheme, we discover novel, gravitationally induced non-Galileon higher-derivative interactions in the effective action. These terms, previously unnoticed within standard, non-covariant frameworks, are not Planck suppressed. Unless tuned to be sub-dominant, their presence could have important implications for the classical and quantum phenomenology of the theory.

  8. Unidades fraseológicas de estructura "verbo + objeto directo" del ámbito semántico 'hablar' en el español popular e informal de Santiago de Chile. Propuesta de una taxonomía sintáctico-semántica (segunda parte (The 'verb + direct object' construction in the semantic field of the verb 'hablar' in informal Spanish of Santiago de Chile: a proposal for a syntactic-semantic taxonomy (second part

    Directory of Open Access Journals (Sweden)

    Mauricio Fuenzalida E.

    2007-12-01

    Full Text Available Se realiza en este trabajo la descripción y taxonomía de un puntual tipo de unidad fraseológica (UF, acotada sintáctica como semánticamente (la de función verbal, con estructura "verbo + objeto directo", con dos unidades lexemáticas distribuidas en tales funciones, y subordinable al ámbito semántico ‘decir’ o ‘hablar’. Concibiendo la aglutinación propia a la UF sobre la base de tres criterios (estadístico, funcional y semántico, es como se determinan sus diversas clases. Resulta singularmente enriquecido en nuestra gradación taxonómica el ámbito de la UF trasparente, y el de la UF de idiomaticidad parcial. Se redefinen y aplican con rigor y compatiblemente los conceptos de "colocación" y "discurso repetido" en nuestra categorización, reparando para ello en la construcción sintáctica que subyace en la UF y en la idiomaticidad léxica de los componentes considerados (verbo y objeto directo. (This study presents a description and taxonomy of a precise type of UF, syntactic as well as semantic (verbal function, with structure 'verb + direct object', two lexematic units distributed in such functions, and related to the semantic field ‘decir’ or ‘hablar’. Their diverse classes are determined considering their agglutination to the UF on the basis of three criteria: statistical, functional and semantic. Specially enriched in our taxonomic gradation is the field of transparent UF, and that of the partial idiomacy UF. The categorization used redefines and applies rigorously the concepts of 'collocation' and 'repeated discourse', considering the syntactic construction that underlies the UF and the lexical idiomacy of the components involved (verb and direct object.

  9. Unidades fraseológicas de estructura "verbo + objeto directo" del ámbito semántico 'hablar' en el español popular e informal de Santiago de Chile. Propuesta de una taxonomía sintáctico-semántica (primera parte (The 'verb + direct object' construction in the semantic field of the verb 'hablar' in informal Spanish of Santiago de Chile: a proposal for a syntactic-semantic taxonomy (first part

    Directory of Open Access Journals (Sweden)

    Mauricio Fuenzalida E.

    2007-06-01

    Full Text Available Se realiza en este trabajo la descripción y taxonomía de un puntual tipo de unidad fraseológica (UF, acotada sintáctica como semánticamente (la de función verbal, con estructura "verbo + objeto directo", con dos unidades lexemáticas distribuidas en tales funciones, y subordinable al ámbito semántico ‘decir’ o ‘hablar’. Concibiendo la aglutinación propia a la UF sobre la base de tres criterios (estadístico, funcional y semántico, es como se determinansus diversas clases. Resulta singularmente enriquecido en nuestra gradación taxonómica el ámbito de la UF trasparente, y el de la UF de idiomaticidad parcial. Se redefinen y aplican con rigor y compatiblemente los conceptos de "colocación" y "discurso repetido" en nuestra categorización, reparando para ello en la construcción sintáctica que subyace en la UF y en la idiomaticidad léxica de los componentes considerados (verbo y objeto directo. (This study presents a description and taxonomy of a precise type of UF, syntactic as well as semantic (verbal function, with structure 'verb + direct object', two lexematic units distributed in such functions, and related to the semantic field ‘decir’ or ‘hablar’. Their diverse classes are determined considering their agglutination to the UF on the basis of three criteria: statistical, functional and semantic. Specially enriched in our taxonomic gradation is the field of transparent UF, and that of the partial idiomacy UF. The categorization used redefines and applies rigorously the concepts of 'collocation' and 'repeated discourse', considering the syntactic construction that underlies the UF and the lexical idiomacy of thecomponents involved (verb and direct object.

  10. Stronger Ties With Chile

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chile was the first South American country to establish diplomatic relations with China. It was also the first Latin American country to support China’s entry into the WTO,recognize China’s full market

  11. Earth Observing System Covariance Realism

    Science.gov (United States)

    Zaidi, Waqar H.; Hejduk, Matthew D.

    2016-01-01

    The purpose of covariance realism is to properly size a primary object's covariance in order to add validity to the calculation of the probability of collision. The covariance realism technique in this paper consists of three parts: collection/calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics. An empirical cumulative distribution function (ECDF) Goodness-of-Fit (GOF) method is employed to determine if a covariance is properly sized by comparing the empirical distribution of Mahalanobis distance calculations to the hypothesized parent 3-DoF chi-squared distribution. To realistically size a covariance for collision probability calculations, this study uses a state noise compensation algorithm that adds process noise to the definitive epoch covariance to account for uncertainty in the force model. Process noise is added until the GOF tests pass a group significance level threshold. The results of this study indicate that when outliers attributed to persistently high or extreme levels of solar activity are removed, the aforementioned covariance realism compensation method produces a tuned covariance with up to 80 to 90% of the covariance propagation timespan passing (against a 60% minimum passing threshold) the GOF tests-a quite satisfactory and useful result.

  12. Universality of Covariance Matrices

    CERN Document Server

    Pillai, Natesh S

    2011-01-01

    We prove the universality of covariance matrices of the form $H_{N \\times N} = {1 \\over N} \\tp{X}X$ where $[X]_{M \\times N}$ is a rectangular matrix with independent real valued entries $[x_{ij}]$ satisfying $\\E \\,x_{ij} = 0$ and $\\E \\,x^2_{ij} = {1 \\over M}$, $N, M\\to \\infty$. Furthermore it is assumed that these entries have sub-exponential tails. We will study the asymptotics in the regime $N/M = d_N \\in (0,\\infty), \\lim_{N\\to \\infty}d_N \

  13. Covariant Magnetic Connection Hypersurfaces

    CERN Document Server

    Pegoraro, F

    2016-01-01

    In the single fluid, nonrelativistic, ideal-Magnetohydrodynamic (MHD) plasma description magnetic field lines play a fundamental role by defining dynamically preserved "magnetic connections" between plasma elements. Here we show how the concept of magnetic connection needs to be generalized in the case of a relativistic MHD description where we require covariance under arbitrary Lorentz transformations. This is performed by defining 2-D {\\it magnetic connection hypersurfaces} in the 4-D Minkowski space. This generalization accounts for the loss of simultaneity between spatially separated events in different frames and is expected to provide a powerful insight into the 4-D geometry of electromagnetic fields when ${\\bf E} \\cdot {\\bf B} = 0$.

  14. Covariant Projective Extensions

    Institute of Scientific and Technical Information of China (English)

    许天周; 梁洁

    2003-01-01

    @@ The theory of crossed products of C*-algebras by groups of automorphisms is a well-developed area of the theory of operator algebras. Given the importance and the success ofthat theory, it is natural to attempt to extend it to a more general situation by, for example,developing a theory of crossed products of C*-algebras by semigroups of automorphisms, or evenof endomorphisms. Indeed, in recent years a number of papers have appeared that are concernedwith such non-classicaltheories of covariance algebras, see, for instance [1-3].

  15. The Covariant Stark Effect

    CERN Document Server

    Land, M C

    2001-01-01

    This paper examines the Stark effect, as a first order perturbation of manifestly covariant hydrogen-like bound states. These bound states are solutions to a relativistic Schr\\"odinger equation with invariant evolution parameter, and represent mass eigenstates whose eigenvalues correspond to the well-known energy spectrum of the non-relativistic theory. In analogy to the nonrelativistic case, the off-diagonal perturbation leads to a lifting of the degeneracy in the mass spectrum. In the covariant case, not only do the spectral lines split, but they acquire an imaginary part which is lnear in the applied electric field, thus revealing induced bound state decay in first order perturbation theory. This imaginary part results from the coupling of the external field to the non-compact boost generator. In order to recover the conventional first order Stark splitting, we must include a scalar potential term. This term may be understood as a fifth gauge potential, which compensates for dependence of gauge transformat...

  16. Bayes linear covariance matrix adjustment

    CERN Document Server

    Wilkinson, Darren J

    1995-01-01

    In this thesis, a Bayes linear methodology for the adjustment of covariance matrices is presented and discussed. A geometric framework for quantifying uncertainties about covariance matrices is set up, and an inner-product for spaces of random matrices is motivated and constructed. The inner-product on this space captures aspects of our beliefs about the relationship between covariance matrices of interest to us, providing a structure rich enough for us to adjust beliefs about unknown matrices in the light of data such as sample covariance matrices, exploiting second-order exchangeability and related specifications to obtain representations allowing analysis. Adjustment is associated with orthogonal projection, and illustrated with examples of adjustments for some common problems. The problem of adjusting the covariance matrices underlying exchangeable random vectors is tackled and discussed. Learning about the covariance matrices associated with multivariate time series dynamic linear models is shown to be a...

  17. Covariant Macroscopic Quantum Geometry

    CERN Document Server

    Hogan, Craig J

    2012-01-01

    A covariant noncommutative algebra of position operators is presented, and interpreted as the macroscopic limit of a geometry that describes a collective quantum behavior of the positions of massive bodies in a flat emergent space-time. The commutator defines a quantum-geometrical relationship between world lines that depends on their separation and relative velocity, but on no other property of the bodies, and leads to a transverse uncertainty of the geometrical wave function that increases with separation. The number of geometrical degrees of freedom in a space-time volume scales holographically, as the surface area in Planck units. Ongoing branching of the wave function causes fluctuations in transverse position, shared coherently among bodies with similar trajectories. The theory can be tested using appropriately configured Michelson interferometers.

  18. Covariant holographic entanglement negativity

    CERN Document Server

    Chaturvedi, Pankaj; Sengupta, Gautam

    2016-01-01

    We conjecture a holographic prescription for the covariant entanglement negativity of $d$-dimensional conformal field theories dual to non static bulk $AdS_{d+1}$ gravitational configurations in the framework of the $AdS/CFT$ correspondence. Application of our conjecture to a $AdS_3/CFT_2$ scenario involving bulk rotating BTZ black holes exactly reproduces the entanglement negativity of the corresponding $(1+1)$ dimensional conformal field theories and precisely captures the distillable quantum entanglement. Interestingly our conjecture for the scenario involving dual bulk extremal rotating BTZ black holes also accurately leads to the entanglement negativity for the chiral half of the corresponding $(1+1)$ dimensional conformal field theory at zero temperature.

  19. Deriving covariant holographic entanglement

    Science.gov (United States)

    Dong, Xi; Lewkowycz, Aitor; Rangamani, Mukund

    2016-11-01

    We provide a gravitational argument in favour of the covariant holographic entanglement entropy proposal. In general time-dependent states, the proposal asserts that the entanglement entropy of a region in the boundary field theory is given by a quarter of the area of a bulk extremal surface in Planck units. The main element of our discussion is an implementation of an appropriate Schwinger-Keldysh contour to obtain the reduced density matrix (and its powers) of a given region, as is relevant for the replica construction. We map this contour into the bulk gravitational theory, and argue that the saddle point solutions of these replica geometries lead to a consistent prescription for computing the field theory Rényi entropies. In the limiting case where the replica index is taken to unity, a local analysis suffices to show that these saddles lead to the extremal surfaces of interest. We also comment on various properties of holographic entanglement that follow from this construction.

  20. Deriving covariant holographic entanglement

    CERN Document Server

    Dong, Xi; Rangamani, Mukund

    2016-01-01

    We provide a gravitational argument in favour of the covariant holographic entanglement entropy proposal. In general time-dependent states, the proposal asserts that the entanglement entropy of a region in the boundary field theory is given by a quarter of the area of a bulk extremal surface in Planck units. The main element of our discussion is an implementation of an appropriate Schwinger-Keldysh contour to obtain the reduced density matrix (and its powers) of a given region, as is relevant for the replica construction. We map this contour into the bulk gravitational theory, and argue that the saddle point solutions of these replica geometries lead to a consistent prescription for computing the field theory Renyi entropies. In the limiting case where the replica index is taken to unity, a local analysis suffices to show that these saddles lead to the extremal surfaces of interest. We also comment on various properties of holographic entanglement that follow from this construction.

  1. Covariant Residual Entropy

    CERN Document Server

    Hubeny, Veronika E

    2014-01-01

    A recently explored interesting quantity in AdS/CFT, dubbed 'residual entropy', characterizes the amount of collective ignorance associated with either boundary observers restricted to finite time duration, or bulk observers who lack access to a certain spacetime region. However, the previously-proposed expression for this quantity involving variation of boundary entanglement entropy (subsequently renamed to 'differential entropy') works only in a severely restrictive context. We explain the key limitations, arguing that in general, differential entropy does not correspond to residual entropy. Given that the concept of residual entropy as collective ignorance transcends these limitations, we identify two correspondingly robust, covariantly-defined constructs: a 'strip wedge' associated with boundary observers and a 'rim wedge' associated with bulk observers. These causal sets are well-defined in arbitrary time-dependent asymptotically AdS spacetimes in any number of dimensions. We discuss their relation, spec...

  2. Contributions to the mammalogy of Chile

    Science.gov (United States)

    Pine, Ronald H.; Miller, Sterling D.; Schamberger, Mel L.

    1979-01-01

    Collections of mammals were made during more than three years of biological investigations in Chile sponsored by the Corporación Nacional Forestal under the aegis of the Peace Corps (Smithsonian Environmental Program). Genera and species hitherto unreported for that country were taken and many useful data concerning distributional patterns of other (mostly little-known) species were gathered. These collections have also proved valuable in better understanding Chilean mammals from a taxonomic point of view and contribute knowledge of the species' natural history. Specimens are to be deposited in the (United States) National Museum of Natural History (USNM) or are to be retained by the Corporación Nacional Forestal, Avda, Bulnes 285, Depto. 401, Santiago. Numbers provided below are field numbers. A final division of specimens between the two institutions has not yet been made. A number of specimens reported here were not taken by Peace Corps personnel but have been obtained by the National Museum of Natural History from other sources. Specimens in the Field Museum of Natural History (FMNH) were used in making comparisons. Some of Fulk's (GWF) specimens are at Texas Tech University. Other are at the Servicio Agricola y Ganadero in Santiago (as are specimens of some introduced species taken by Schamberger). Reise's (DF) are at the Universidad de Chile-Concepción and in his personal collection.

  3. Chile's Madam President

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    After becoming the first female to win a presidential election in the socially conservative country, Chilean President-elect Michelle Bachelet created history again when unveiling a cabinet that was absolutely gender-balanced on January 30. Following similar breakthroughs of women politicians in Liberia and Germany, what happened in Chile is considered another case of women gaining power worldwide.

  4. Covariant representations of subproduct systems

    CERN Document Server

    Viselter, Ami

    2010-01-01

    A celebrated theorem of Pimsner states that a covariant representation $T$ of a $C^*$-correspondence $E$ extends to a $C^*$-representation of the Toeplitz algebra of $E$ if and only if $T$ is isometric. This paper is mainly concerned with finding conditions for a covariant representation of a \\emph{subproduct system} to extend to a $C^*$-representation of the Toeplitz algebra. This framework is much more general than the former. We are able to find sufficient conditions, and show that in important special cases, they are also necessary. Further results include the universality of the tensor algebra, dilations of completely contractive covariant representations, Wold decompositions and von Neumann inequalities.

  5. Metagenomic covariation along densely sampled environmental gradients in the Red Sea

    KAUST Repository

    Thompson, Luke R

    2016-07-15

    Oceanic microbial diversity covaries with physicochemical parameters. Temperature, for example, explains approximately half of global variation in surface taxonomic abundance. It is unknown, however, whether covariation patterns hold over narrower parameter gradients and spatial scales, and extending to mesopelagic depths. We collected and sequenced 45 epipelagic and mesopelagic microbial metagenomes on a meridional transect through the eastern Red Sea. We asked which environmental parameters explain the most variation in relative abundances of taxonomic groups, gene ortholog groups, and pathways—at a spatial scale of <2000 km, along narrow but well-defined latitudinal and depth-dependent gradients. We also asked how microbes are adapted to gradients and extremes in irradiance, temperature, salinity, and nutrients, examining the responses of individual gene ortholog groups to these parameters. Functional and taxonomic metrics were equally well explained (75–79%) by environmental parameters. However, only functional and not taxonomic covariation patterns were conserved when comparing with an intruding water mass with different physicochemical properties. Temperature explained the most variation in each metric, followed by nitrate, chlorophyll, phosphate, and salinity. That nitrate explained more variation than phosphate suggested nitrogen limitation, consistent with low surface N:P ratios. Covariation of gene ortholog groups with environmental parameters revealed patterns of functional adaptation to the challenging Red Sea environment: high irradiance, temperature, salinity, and low nutrients. Nutrient-acquisition gene ortholog groups were anti-correlated with concentrations of their respective nutrient species, recapturing trends previously observed across much larger distances and environmental gradients. This dataset of metagenomic covariation along densely sampled environmental gradients includes online data exploration supplements, serving as a community

  6. Exploring historical trends using taxonomic name metadata

    Directory of Open Access Journals (Sweden)

    Schenk Ryan

    2008-05-01

    Full Text Available Abstract Background Authority and year information have been attached to taxonomic names since Linnaean times. The systematic structure of taxonomic nomenclature facilitates the ability to develop tools that can be used to explore historical trends that may be associated with taxonomy. Results From the over 10.7 million taxonomic names that are part of the uBio system 4, approximately 3 million names were identified to have taxonomic authority information from the years 1750 to 2004. A pipe-delimited file was then generated, organized according to a Linnaean hierarchy and by years from 1750 to 2004, and imported into an Excel workbook. A series of macros were developed to create an Excel-based tool and a complementary Web site to explore the taxonomic data. A cursory and speculative analysis of the data reveals observable trends that may be attributable to significant events that are of both taxonomic (e.g., publishing of key monographs and societal importance (e.g., world wars. The findings also help quantify the number of taxonomic descriptions that may be made available through digitization initiatives. Conclusion Temporal organization of taxonomic data can be used to identify interesting biological epochs relative to historically significant events and ongoing efforts. We have developed an Excel workbook and complementary Web site that enables one to explore taxonomic trends for Linnaean taxonomic groupings, from Kingdoms to Families.

  7. General covariance in computational electrodynamics

    DEFF Research Database (Denmark)

    Shyroki, Dzmitry; Lægsgaard, Jesper; Bang, Ole;

    2007-01-01

    We advocate the generally covariant formulation of Maxwell equations as underpinning some recent advances in computational electrodynamics—in the dimensionality reduction for separable structures; in mesh truncation for finite-difference computations; and in adaptive coordinate mapping as opposed...

  8. Chile exploits LNG

    Energy Technology Data Exchange (ETDEWEB)

    1980-03-01

    Simultaneously with its exploitation of offshore hydrocarbon reservoirs Chile is developing the production and selling of LNG. Chile produces a large quantity of associated gas from its reservoirs at Megallanes and processes it at the Manantiales, Cullen and Posesion plants recovering propane, butane and natural gas liguids. The stripped gas is reinjected for pressure maintenance operations. With the completion of the LNG program full use of the gas will be achieved. It will totally meet the needs of combustible liquids for the central and northern parts of the country, a volume of 2200 million cu m/yr. For its treatment natural gas is sent through gas pipelines to the LNG plant at Cabo Negro. By means of a cooling process, the gas is cooled to -160 C where it becomes a liquid and its volume is reduced by a factor of 600. It is then stored in tanks at atmospheric pressure.

  9. Chile: segundo tiempo Chile: Half-time

    Directory of Open Access Journals (Sweden)

    ROBERT L FUNK

    2009-01-01

    Full Text Available El artículo examina el año político chileno, ofreciendo un análisis crítico del concepto de 'segundo tiempo' autoimpuesto por la presidenta Michelle Bachelet a comienzos del 2008. Resumiendo algunas de las políticas implementadas, el trabajo cuestiona si se logró marcar una linea y dejar atrás los dos primeros y difíciles años del cuarto gobierno de la Concertación. Analizando las medidas tomadas y las encuestas de opinión pública, se encuentra que el reenfoque de las prioridades del gobierno y una complicada coyuntura externa ayudó a levantar los niveles de apoyo de la presidenta y su gobierno.The article examines the political year in Chile, offering a critical analysis of the concept of 'Second Period' which President Michelle Bachelet defined at the beginning of 2008. Summarising some of the policies implemented, the piece asks whether the government was able to draw a line, leaving behind the first, difficult two years of the Concertación s fourth government. Analyzing the measures taken and public opinion polls, the paper finds that a re-focussing of the government's priorities together with a complicated external environment helped to raise support for the president as well as her government.

  10. Covariate-free and Covariate-dependent Reliability.

    Science.gov (United States)

    Bentler, Peter M

    2016-12-01

    Classical test theory reliability coefficients are said to be population specific. Reliability generalization, a meta-analysis method, is the main procedure for evaluating the stability of reliability coefficients across populations. A new approach is developed to evaluate the degree of invariance of reliability coefficients to population characteristics. Factor or common variance of a reliability measure is partitioned into parts that are, and are not, influenced by control variables, resulting in a partition of reliability into a covariate-dependent and a covariate-free part. The approach can be implemented in a single sample and can be applied to a variety of reliability coefficients.

  11. Levy Matrices and Financial Covariances

    Science.gov (United States)

    Burda, Zdzislaw; Jurkiewicz, Jerzy; Nowak, Maciej A.; Papp, Gabor; Zahed, Ismail

    2003-10-01

    In a given market, financial covariances capture the intra-stock correlations and can be used to address statistically the bulk nature of the market as a complex system. We provide a statistical analysis of three SP500 covariances with evidence for raw tail distributions. We study the stability of these tails against reshuffling for the SP500 data and show that the covariance with the strongest tails is robust, with a spectral density in remarkable agreement with random Lévy matrix theory. We study the inverse participation ratio for the three covariances. The strong localization observed at both ends of the spectral density is analogous to the localization exhibited in the random Lévy matrix ensemble. We discuss two competitive mechanisms responsible for the occurrence of an extensive and delocalized eigenvalue at the edge of the spectrum: (a) the Lévy character of the entries of the correlation matrix and (b) a sort of off-diagonal order induced by underlying inter-stock correlations. (b) can be destroyed by reshuffling, while (a) cannot. We show that the stocks with the largest scattering are the least susceptible to correlations, and likely candidates for the localized states. We introduce a simple model for price fluctuations which captures behavior of the SP500 covariances. It may be of importance for assets diversification.

  12. Primary Medical Care in Chile

    DEFF Research Database (Denmark)

    Scarpaci, Joseph L.

    Primary medical care in Chile: accessibility under military rule [Front Cover] [Front Matter] [Title Page] Contents Tables Figures Preface Chapter 1: Introduction Chapter 2: The Restructuring of Medical Care Financing in Chile Chapter 3: Inflation and Medical Care Accessibility Chapter 4: Help......-Seeking Behavior of the Urban Poor Chapter 5: Spatial Organization and Medical Care Accessibility Chapter 6: Conclusion...

  13. Covariance evaluation work at LANL

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Los Alamos National Laboratory; Talou, Patrick [Los Alamos National Laboratory; Young, Phillip [Los Alamos National Laboratory; Hale, Gerald [Los Alamos National Laboratory; Chadwick, M B [Los Alamos National Laboratory; Little, R C [Los Alamos National Laboratory

    2008-01-01

    Los Alamos evaluates covariances for nuclear data library, mainly for actinides above the resonance regions and light elements in the enUre energy range. We also develop techniques to evaluate the covariance data, like Bayesian and least-squares fitting methods, which are important to explore the uncertainty information on different types of physical quantities such as elastic scattering angular distribution, or prompt neutron fission spectra. This paper summarizes our current activities of the covariance evaluation work at LANL, including the actinide and light element data mainly for the criticality safety study and transmutation technology. The Bayesian method based on the Kalman filter technique, which combines uncertainties in the theoretical model and experimental data, is discussed.

  14. Szekeres models: a covariant approach

    CERN Document Server

    Apostolopoulos, Pantelis S

    2016-01-01

    We exploit the 1+1+2 formalism to covariantly describe the inhomogeneous and anisotropic Szekeres models. It is shown that an \\emph{average scale length} can be defined \\emph{covariantly} which satisfies a 2d equation of motion driven from the \\emph{effective gravitational mass} (EGM) contained in the dust cloud. The contributions to the EGM are encoded to the energy density of the dust fluid and the free gravitational field $E_{ab}$. In addition the notions of the Apparent and Absolute Apparent Horizons are briefly discussed and we give an alternative gauge-invariant form to define them in terms of the kinematical variables of the spacelike congruences. We argue that the proposed program can be used in order to express the Sachs optical equations in a covariant form and analyze the confrontation of a spatially inhomogeneous irrotational overdense fluid model with the observational data.

  15. Cosmic Censorship Conjecture revisited: Covariantly

    CERN Document Server

    Hamid, Aymen I M; Maharaj, Sunil D

    2014-01-01

    In this paper we study the dynamics of the trapped region using a frame independent semi-tetrad covariant formalism for general Locally Rotationally Symmetric (LRS) class II spacetimes. We covariantly prove some important geometrical results for the apparent horizon, and state the necessary and sufficient conditions for a singularity to be locally naked. These conditions bring out, for the first time in a quantitative and transparent manner, the importance of the Weyl curvature in deforming and delaying the trapped region during continual gravitational collapse, making the central singularity locally visible.

  16. Chile rural electrification cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Flowers, L. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-01

    The author describes a joint program to use renewables for rural electrification projects in Chile. The initial focus was in a limited part of the country, involving wind mapping, pilot project planning, training, and development of methodologies for comparative evaluations of resources. To this point three wind hybrid systems have been installed in one region, as a part of the regional private utility, and three additional projects are being designed. Additional resource assessment and training is ongoing. The author points out the difficulties in working with utilities, the importance of signed documentation, and the need to look at these programs as long term because of the time involved in introducing such new technologies.

  17. Biomasa en Chile

    OpenAIRE

    Nilsson Cifuentes, Gabriel; Rodríguez Monroy, Carlos

    2012-01-01

    El artículo presenta el desarrollo de la biomasa en Chile, dentro del complejo marco energético existente en el país, el cual, aún no logra potenciar e incentivar el desarrollo de energías renovables y depende fuertemente de los combustibles fósiles, acrecentando el riesgo latente de sufrir una crisis energética, en el mediano plazo, producto de la paulatina incorporación de nuevas centrales generadoras de energías, que satisfagan la creciente demanda energética pronosticada. Este ar...

  18. Chile: Transantiago recargado Chile: Transantiago Reloaded

    Directory of Open Access Journals (Sweden)

    RODRIGO MARDONES Z

    2008-01-01

    Full Text Available El 2007 fue el segundo año del gobierno de Michelle Bachelet. Se trató de un año sin elecciones; con un buen desempeño económico, a pesar de una inflación creciente en los últimos meses; y marcado por la discusión sobre escándalos de corrupción. Sin embargo, lo que más afectó al Gobierno fue la desastrosa puesta en marcha de la reforma al sistema de transporte público de la capital: Transantiago. Este puso un velo sobre los importantes avances en materias previsionales y educacionales, cuestionando no sólo la capacidad ejecutiva del Gobierno, sino que profundizando un flanco de indisciplina al interior de la coalición oficialista (Concertación; síntoma de su desgaste después de 17 años ocupando la Presidencia de Chile.The year 2007 was the second in Michelle Bachelet’s presidencial term. It was a year free of elections, exhibiting a fairly good economic performance, despite the high rate of inflation shown during the last months. Public discussion on corruption escandals was frequent; however, the most important issue was the disestrous beginning of the reform on the public transportation system of the country’s capital: Transantiago. This has placed a veil over the important achievements on the pension system and education, questioning not only the government’s capacity, but also opening and edge of indiscipline within the ruling coalition (Concertación, which is a symtom of its erosion after 17 years in the presidential office.

  19. [Taxonomic theory for non-classical systematics].

    Science.gov (United States)

    Pavlinov, I Ia

    2012-01-01

    Outlined briefly are basic principles of construing general taxonomic theory for biological systematics considered in the context of non-classical scientific paradigm. The necessity of such kind of theory is substantiated, and some key points of its elaboration are exposed: its interpretation as a framework concept for the partial taxonomic theories in various schools of systematics; elaboration of idea of cognitive situation including three interrelated components, namely subject, object, and epistemic ones; its construing as a content-wisely interpreted quasi-axiomatics, with strong structuring of its conceptual space including demarcation between axioms and inferring rules; its construing as a "conceptual pyramid" of concepts of various levels of generality; inclusion of a basic model into definition of the taxonomic system (classification) regulating its content. Two problems are indicated as fundamental: definition of taxonomic diversity as a subject domain for the systematics as a whole; definition of onto-epistemological status of taxonomic system (classification) in general and of taxa in particular.

  20. 27 CFR 9.154 - Chiles Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Chiles Valley. 9.154... Chiles Valley. (a) Name. The name of the viticultural area described in this section is “Chiles Valley.” (b) Approved maps. The appropriate maps for determining the boundary of the Chiles...

  1. Covariant description of isothermic surfaces

    CERN Document Server

    Tafel, Jacek

    2014-01-01

    We present a covariant formulation of the Gauss-Weingarten equations and the Gauss-Mainardi-Codazzi equations for surfaces in 3-dimensional curved spaces. We derive a coordinate invariant condition on the first and second fundamental form which is necessary and sufficient for the surface to be isothermic.

  2. Relativistic covariance of Ohm's law

    CERN Document Server

    Starke, R

    2014-01-01

    The derivation of relativistic generalizations of Ohm's law has been a long-term issue in theoretical physics with deep implications for the study of relativistic plasmas in astrophysics and cosmology. Here we propose an alternative route to this problem by introducing the most general Lorentz covariant first order response law, which is written in terms of the fundamental response tensor $\\chi^\\mu_{~\

  3. Fires in Chile

    Science.gov (United States)

    2002-01-01

    On February 5, 2002, the dense smoke from numerous forest fires stretched out over the Pacific Ocean about 400 miles south of Santiago, Chile. This true-color Moderate-resolution Imaging Spectroradiometer (MODIS) image shows the fires, which are located near the city of Temuco. The fires are indicated with red dots (boxes in the high-resolution imagery). The fires were burning near several national parks and nature reserves in an area of the Chilean Andes where tourism is very popular. Southeast of the fires, the vegetation along the banks of the Rio Negro in Argentina stands out in dark green. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  4. Eso's Situation in Chile

    Science.gov (United States)

    1995-02-01

    ESO, the European Southern Observatory, in reply to questions raised by the international media, as well as an ongoing debate about the so-called "Paranal case" in Chilean newspapers, would like to make a number of related observations concerning its status and continued operation in that country [1]. THE ESO OBSERVATORY SITES IN CHILE The European Southern Observatory, an international organisation established and supported by eight European countries, has been operating more than 30 years in the Republic of Chile. Here ESO maintains one of the world's prime astronomical observatories on the La Silla mountain in the southern part of the Atacama desert. This location is in the Fourth Chilean Region, some 600 km north of Santiago de Chile. In order to protect the La Silla site against dust and light pollution from possible future mining industries, roads and settlements, ESO early acquired the territory around this site. It totals about 825 sq. km and has effectively contributed to the preservation of its continued, excellent "astronomical" quality. Each year, more than 500 astronomers from European countries, Chile and elsewhere profit from this when they come to La Silla to observe with one or more of the 15 telescopes now located there. In 1987, the ESO Council [2] decided to embark upon one of the most prestigious and technologically advanced projects ever conceived in astronomy, the Very Large Telescope (VLT). It will consist of four interconnected 8.2-metre telescopes and will become the largest optical telescope in the world when it is ready. It is safe to predict that many exciting discoveries will be made with this instrument, and it will undoubtedly play a very important role in our exploration of the distant universe and its many mysteries during the coming decades. THE VLT AND PARANAL In order to find the best site for the VLT, ESO performed a thorough investigation of many possible mountain tops, both near La Silla and in Northern Chile. They showed

  5. Asteroid taxonomic signatures from photometric phase curves

    CERN Document Server

    Oszkiewicz, D A; Wasserman, L H; Muinonen, K; Penttilä, A; Pieniluoma, T; Trilling, D E; Thomas, C A

    2012-01-01

    We explore the correlation between an asteroid's taxonomy and photometric phase curve using the H, G12 photometric phase function, with the shape of the phase function described by the single parameter G12. We explore the usability of G12 in taxonomic classification for individual objects, asteroid families, and dynamical groups. We conclude that the mean values of G12 for the considered taxonomic complexes are statistically different, and also discuss the overall shape of the G12 distribution for each taxonomic complex. Based on the values of G12 for about half a million asteroids, we compute the probabilities of C, S, and X complex membership for each asteroid. For an individual asteroid, these probabilities are rather evenly distributed over all of the complexes, thus preventing meaningful classification. We then present and discuss the G12 distributions for asteroid families, and predict the taxonomic complex preponderance for asteroid families given the distribution of G12 in each family. For certain ast...

  6. Discrete Symmetries in Covariant LQG

    CERN Document Server

    Rovelli, Carlo

    2012-01-01

    We study time-reversal and parity ---on the physical manifold and in internal space--- in covariant loop gravity. We consider a minor modification of the Holst action which makes it transform coherently under such transformations. The classical theory is not affected but the quantum theory is slightly different. In particular, the simplicity constraints are slightly modified and this restricts orientation flips in a spinfoam to occur only across degenerate regions, thus reducing the sources of potential divergences.

  7. Phenotypic covariance at species’ borders

    Science.gov (United States)

    2013-01-01

    Background Understanding the evolution of species limits is important in ecology, evolution, and conservation biology. Despite its likely importance in the evolution of these limits, little is known about phenotypic covariance in geographically marginal populations, and the degree to which it constrains, or facilitates, responses to selection. We investigated phenotypic covariance in morphological traits at species’ borders by comparing phenotypic covariance matrices (P), including the degree of shared structure, the distribution of strengths of pair-wise correlations between traits, the degree of morphological integration of traits, and the ranks of matricies, between central and marginal populations of three species-pairs of coral reef fishes. Results Greater structural differences in P were observed between populations close to range margins and conspecific populations toward range centres, than between pairs of conspecific populations that were both more centrally located within their ranges. Approximately 80% of all pair-wise trait correlations within populations were greater in the north, but these differences were unrelated to the position of the sampled population with respect to the geographic range of the species. Conclusions Neither the degree of morphological integration, nor ranks of P, indicated greater evolutionary constraint at range edges. Characteristics of P observed here provide no support for constraint contributing to the formation of these species’ borders, but may instead reflect structural change in P caused by selection or drift, and their potential to evolve in the future. PMID:23714580

  8. Competing risks and time-dependent covariates

    DEFF Research Database (Denmark)

    Cortese, Giuliana; Andersen, Per K

    2010-01-01

    Time-dependent covariates are frequently encountered in regression analysis for event history data and competing risks. They are often essential predictors, which cannot be substituted by time-fixed covariates. This study briefly recalls the different types of time-dependent covariates...

  9. Covariance Evaluation Methodology for Neutron Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  10. complejidad en Chile

    Directory of Open Access Journals (Sweden)

    Miguel Alejandro Bustamante-Ubilla

    2015-01-01

    Full Text Available El presente estudio tiene por objetivo caracterizar el clima organizacional al interior de 2 hospitales dealta complejidad de Chile, determinando las dimensiones más y menos influyentes. Para su desarrollose aplicó un cuestionario que consta de 71 variables agrupadas en 14 dimensiones a una muestra de561 funcionarios. La interpretación de los resultados se realizó a través del análisis del valor prome-dio estandarizado y su confiabilidad ratificada mediante el alfa de Cronbach. A partir de lo anterior, sedeterminó que las dimensiones que influyen por encima del promedio fueron: identidad, motivaciónlaboral y responsabilidad; en tanto que las dimensiones que muestran un nivel de impacto por debajodel promedio resultaron ser: equipo y distribución de personas y material, administración del conflictoy comunicación.© 2015 Universidad ICESI. Publicado por Elsevier España, S.L.U. Este es un artículo Open Access bajo lalicencia CC BY (http://creativecommons.org/licenses/by/4.0/.

  11. [Chile: Standing up again].

    Science.gov (United States)

    Reyes B, Humberto

    2010-03-01

    One of the biggest earthquakes recorded in human history has recently devastated a large part of the Chilean territory and, followed by a Tsunami, destroyed cities, seaports, fishermen's coves, bridges, and countryside houses. This cataclysm affected a large proportion of our population, leaving homeless families, no working tools for work places, hospitals, schools, public buildings, museums. However, the loss of human Uves was small compared to similar disasters. It destroyed part of the national heritage as well as damaged people's living conditions. A national movement started immediately to help and recover, and international resources, both human and technological were also set in motion. As after previous earthquakes in Chile, young M.D.'s and medical students were organized in voluntary groups backed by institutions or by their own organizations and went from large cities as Santiago and others to provide medical and psychological care to those in most need. Young members and students of other health professions (nurses, physical therapists, etc.) were included in these groups or worked in their own ones. National and international experience indicates that the forthcoming months require special care of psychological reactions and sequel (posttraumatic stress symptoms) and health consequences after water pollution, restrictions in housing and deteriorated sanitary conditions. Nevertheless, our country will stand up once more.

  12. Country watch: Chile.

    Science.gov (United States)

    Montoya Leiva, M

    1996-01-01

    Servicio Paz y Justicia (SERPAJ) is a nongovernmental organization (NGO) established in Chile in 1977. It supports fundamental human dignity and rights by fighting discrimination and exclusion based upon individual differences. SERPAJ promotes training, organization, and the political participation of community members as part of the democratic process, working mainly with the at risk women, street children, and youth of Santiago's working-class neighborhoods. Groups participate in workshops and training courses on human rights and development, civic education, and methods of non-violent community action. In 1987, SERPAJ-Sur Oriente began to include the topic of sexuality and AIDS/STDs in courses training working-class women as community human rights agents. The NGO is therefore one of the first mainstream Chilean human rights organizations to incorporate HIV/AIDS issues. A basic facts brochure was developed, followed by a pilot education project developed in one neighborhood which was then systematically replicated in other neighborhoods. The comments of some people who have participated in SERPAJ workshops are presented.

  13. Converting Taxonomic Descriptions to New Digital Formats

    Directory of Open Access Journals (Sweden)

    Hong Cui

    2008-01-01

    Full Text Available Abstract.--The majority of taxonomic descriptions is currently in print format. The majority of digital descriptions are in formats such as DOC, HTML, or PDF and for human readers. These formats do not convey rich semantics in taxonomic descriptions for computer-aided process. Newer digital formats such as XML and RDF accommodate semantic annotations that allow computers to process the rich semantics on human's behalf, thus open up opportunities for a wide range of innovative usages of taxonomic descriptions, such as searching in more precise and flexible ways, integrating with gnomic and geographic information, generating taxonomic keys automatically, and text data mining and information visualization etc. This paper discusses the challenges in automated conversion of multiple collections of descriptions to XML format and reports an automated system, MARTT. MARTT is a machine-learning system that makes use of training examples to tag new descriptions into XML format. A number of utilities are implemented as solutions to the challenges. The utilities are used to reduce the effort for training example preparation, to facilitate the creation of a comprehensive schema, and to predict system performance on a new collection of descriptions. The system has been tested with several plant and alga taxonomic publications including Flora of China and Flora of North America.

  14. It Pays to Invest in Chile

    Institute of Scientific and Technical Information of China (English)

    Li Zhen

    2011-01-01

    @@ Chile is the first country to establish coopera-tive relations with China in South America, and also the first one to support China's ac-cession to the World Trade Organization.In 2005, Chile and China signed a free trade agreement.After that, China has become Chile's largest trad-ing partner, and Chile become China's second largest partner in South America.

  15. Modernitet og forbrugskultur i Chile

    DEFF Research Database (Denmark)

    Cristoffanini, Pablo Rolando

    2012-01-01

    I de sidste årtier er Chile blevet et egentligt forbrugersamfund. Udbredelsen af forbrugskulturen og forbrugerismen er centrale fænomener i chilenernes dagligliv og har nået et omfang, som har konsekvenser for de borgere, der ikke kan deltage fuldt ud heri, noget som er typisk for et samfund med en...... ujævn økonomisk udvikling og med store sociale forskelle. Denne proces er ikke et produkt af en stille, fredelig og naturlig samfundsudvikling, således som magteliten og de toneangivende intellektuelle i Chile har fremstillet det. Som jeg vil vise, er skabelsen af et egentlig forbrugssamfund knyttet til...... til i dag. Ifølge disse er Chile blevet et moderne samfund netop i kraft af, at Chile er et ægte forbrugersamfund med alt, hvad dette indebærer, såvel materielt som symbolsk. For det tredje er billedet af Chile som en ”supermoderne” nation i den latinamerikanske kontekst en udbredt forestilling hos...

  16. China and Chile Signing Free Trade Agreement

    Institute of Scientific and Technical Information of China (English)

    Shen; Danyang

    2005-01-01

      Mr. Bo Xilai, Minister of Commerce of China, and Mr.Walker, Foreign Minister of Chile, signed the China-Chile FTA on behalf of their respective government on November 18, 2005. Chinese President Hu Jintao and Chile President Lagos attended the signing ceremony, according to a press release on the website of Network Center of MOFCOM.……

  17. China and Chile Signing Free Trade Agreement

    Institute of Scientific and Technical Information of China (English)

    Shen Danyang

    2005-01-01

    @@ Mr. Bo Xilai, Minister of Commerce of China, and Mr.Walker, Foreign Minister of Chile, signed the China-Chile FTA on behalf of their respective government on November 18, 2005. Chinese President Hu Jintao and Chile President Lagos attended the signing ceremony, according to a press release on the website of Network Center of MOFCOM.

  18. Wildfires in Chile: A review

    Science.gov (United States)

    Úbeda, Xavier; Sarricolea, Pablo

    2016-11-01

    This paper reviews the literature examining the wildfire phenomenon in Chile. Since ancient times, Chile's wildfires have shaped the country's landscape, but today, as in many other parts of the world, the fire regime - pattern, frequency and intensity - has grown at an alarming rate. In 2014, > 8000 fires were responsible for burning c. 130,000 ha, making it the worst year in Chile's recent history. The reasons for this increase appear to be the increment in the area planted with flammable species; the rejection of these landscape modifications on the part of local communities that target these plantations in arson attacks; and, the adoption of intensive forest management practices resulting in the accumulation of a high fuel load. These trends have left many native species in a precarious situation and forest plantation companies under considerable financial pressure. An additional problem is posed by fires at the wildland urban interface (WUI), threatening those inhabitants that live in Chile's most heavily populated cities. The prevalence of natural fires in Chile; the relationship between certain plant species and fire in terms of seed germination strategies and plant adaptation; the relationship between fire and invasive species; and, the need for fire prevention systems and territorial plans that include fire risk assessments are some of the key aspects discussed in this article. Several of the questions raised will require further research, including just how fire-dependent the ecosystems in Chile are, how the forest at the WUI can be better managed to prevent human and material damage, and how best to address the social controversy that pits the Mapuche population against the timber companies.

  19. Chile Energy Policy Review 2009

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-22

    Since 1990, Chile has been the fastest growing economy in Latin America thanks to sound economic management and integration into the global economy. Chile can also be proud of its energy policy achievements. The pioneering privatisation and liberalisation of its electricity sector in the 1980s was the foundation for a competitive energy sector, which has sustained the rapid growth of the Chilean economy over the past two decades. Nonetheless, Chile faces the continuing challenge of finding additional energy supplies to fuel economic growth. Chile has limited fossil energy resources and depends on imports to meet three-quarters of its energy needs. The country's electricity sector has faced three periods of significant stress over the past decade. The last episode took place in 2007/2008, when the loss of natural gas imports from Argentina was further exacerbated by a drought in the central system, where hydropower normally accounts for over half of electricity generation. Drawing on the experience of IEA member countries, the Review assesses Chile's major energy challenges and provides recommendations. Six main themes emerge: the successful liberalisation of the power sector in the 1980s; the essential role played by the state in ensuring energy security; the re-formulation of Chile's long-term energy policy; the proposed reorganisation of the institutional framework; greater independence for the system operators; and the need for a clear framework of regulation so that long-term investment decisions integrate social and environmental costs. This publication is essential reading for all who are interested in Chilean energy issues and in learning about the important role sound energy policy can play in developing a nation's economic and social welfare.

  20. ISSUES IN NEUTRON CROSS SECTION COVARIANCES

    Energy Technology Data Exchange (ETDEWEB)

    Mattoon, C.M.; Oblozinsky,P.

    2010-04-30

    We review neutron cross section covariances in both the resonance and fast neutron regions with the goal to identify existing issues in evaluation methods and their impact on covariances. We also outline ideas for suitable covariance quality assurance procedures.We show that the topic of covariance data remains controversial, the evaluation methodologies are not fully established and covariances produced by different approaches have unacceptable spread. The main controversy is in very low uncertainties generated by rigorous evaluation methods and much larger uncertainties based on simple estimates from experimental data. Since the evaluators tend to trust the former, while the users tend to trust the latter, this controversy has considerable practical implications. Dedicated effort is needed to arrive at covariance evaluation methods that would resolve this issue and produce results accepted internationally both by evaluators and users.

  1. Covariant diagrams for one-loop matching

    CERN Document Server

    Zhang, Zhengkang

    2016-01-01

    We present a diagrammatic formulation of recently-revived covariant functional approaches to one-loop matching from an ultraviolet (UV) theory to a low-energy effective field theory. Various terms following from a covariant derivative expansion (CDE) are represented by diagrams which, unlike conventional Feynman diagrams, involve gauge-covariant quantities and are thus dubbed "covariant diagrams." The use of covariant diagrams helps organize and simplify one-loop matching calculations, which we illustrate with examples. Of particular interest is the derivation of UV model-independent universal results, which reduce matching calculations of specific UV models to applications of master formulas. We show how such derivation can be done in a more concise manner than the previous literature, and discuss how additional structures that are not directly captured by existing universal results, including mixed heavy-light loops, open covariant derivatives, and mixed statistics, can be easily accounted for.

  2. Parameter inference with estimated covariance matrices

    CERN Document Server

    Sellentin, Elena

    2015-01-01

    When inferring parameters from a Gaussian-distributed data set by computing a likelihood, a covariance matrix is needed that describes the data errors and their correlations. If the covariance matrix is not known a priori, it may be estimated and thereby becomes a random object with some intrinsic uncertainty itself. We show how to infer parameters in the presence of such an estimated covariance matrix, by marginalising over the true covariance matrix, conditioned on its estimated value. This leads to a likelihood function that is no longer Gaussian, but rather an adapted version of a multivariate $t$-distribution, which has the same numerical complexity as the multivariate Gaussian. As expected, marginalisation over the true covariance matrix improves inference when compared with Hartlap et al.'s method, which uses an unbiased estimate of the inverse covariance matrix but still assumes that the likelihood is Gaussian.

  3. Fourth Generation Warfare in Chile: Illicit Drug Trafficking Threats

    Science.gov (United States)

    2011-03-21

    Investigations Police of Chile (Policia de Investigaciones de Chile – PDI). Carabineros de Chile is the uniformed Chilean national police force created in...Chile also has an investigative police force, the Investigations Police of Chile (Policia de Investigaciones de Chile, PDI). This is the civil police... Investigaciones de Chile Homepage, http://www.investigaciones.cl/ (accessed February 20, 2011). 56 CONACE Homepage http://www.conacedrogas.cl/portal

  4. A review of the non-bulimulid terrestrial Mollusca from the Region of Atacama, northern Chile

    Science.gov (United States)

    Araya, Juan Francisco; Catalán, Ricardo

    2014-01-01

    Abstract Terrestrial mollusca are sparsely studied in Chile and, for the first time, a formal record of the diversity of land snails in northern Chile is reported. Coastal and desertic areas in the Region of Atacama, in the border of the Atacama desert and the Pacific Ocean, were surveyed with the aim to describe the presence and distribution of this poorly known fauna. Of the fourteen species recorded, the geographic distribution records for nine species are extended, and some taxa are recorded for the first time since their original descriptions. All, except one, of the fourteen terrestrial molluscan species occurring in the area are endemic to Chile; they are all terrestrial species, most of them have a restricted geographic distribution, and none of them is currently protected by law. The results reveal that the region of Atacama has one of the most diverse terrestrial snail biodiversity in Chile, ranking only after the Juan Fernandez Archipelago. Distribution records of all the studied species and a taxonomic key are also provided. PMID:24715800

  5. The shallow-water chitons (Mollusca, Polyplacophora of Caldera, Region of Atacama, northern Chile

    Directory of Open Access Journals (Sweden)

    Juan Francisco Araya

    2015-03-01

    Full Text Available The Molluscan species of the northern littoral of Chile have been sparsely studied. This work reviews for the first time the diversity of polyplacophoran molluscs around the port of Caldera, in the Region of Atacama (26°45’49”S; 70°45’17”W to 27°20’23”S; 70°56’46”W, northern Chile. Eleven species were found in this study: Acanthopleura echinata (Barnes, 1824; Callistochiton pulchellus (Gray, 1828; Calloplax vivipara (Plate, 1899, Chaetopleura peruviana (Lamarck, 1819; Chiton cumingsii Frembly, 1827; Chiton granosus Frembly, 1827; Chiton magnificus Deshayes, 1827; Enoplochiton niger (Barnes, 1824, Radsia barnesii (Gray, 1828, Tonicia atrata (G. B. Sowerby II, 1840 and Tonicia chilensis (Frembly, 1827. All of the species occurring in the area have distributions in the southeastern Pacific Ocean, from Ecuador to central Chile, and three of them are species endemic to the Chilean coasts (Calloplax vivipara, Radsia barnesii, and Tonicia atrata. This diversity of species is comparable to that of better surveyed faunas of central and southern Chile or Patagonia. Of the eleven species recorded, the geographic distribution records for Callistochiton pulchellus, Radsia barnesii and Tonicia atrata are extended, and Calloplax vivipara is found alive again after 40 years, filling a gap in its known distribution. Illustrations of living specimens in their habitat, distribution records and a taxonomic key for all the studied taxa are also provided.

  6. Women and Politics in Chile.

    Science.gov (United States)

    Kirkwood, Julieta

    1983-01-01

    Political parties in Chile of both the left and right have focused more on drawing women into their ideologies than on considering what political issues mean to women. A look at feminist thought shows how political life for women includes not only the traditional political arena but also domestic life. (IS)

  7. The biomethane potential in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Seiffert, M.; Miranda, J.A. [Institute for Energy and Environment gGmbH, German Biomass Research Centre, Torgauer Strasse 116, 04347 Leipzig (Germany); Kaltschmitt, M. [Institute for Energy and Environment gGmbH, German Biomass Research Centre, Torgauer Strasse 116, 04347 Leipzig (Germany); Institute of Environmental Technology and Energy Economics, Hamburg University of Technology, Eissendorfer Strasse 40, D-21073 Hamburg (Germany)

    2009-04-15

    Within the last decade natural gas gained considerable importance in Chile. The contribution of natural gas within the energy system will increase in the future by predicted 3.6% annually until the year 2015. Due to limited resources within its own country, the energy system of Chile depends on natural gas imports preferential from Argentina. Therefore, the aim of several stakeholders from policy and industry is to reduce the share of imported primary energy within the overall energy system. In order to reach this goal, the use of domestic resources and particularly the utilisation of biomass as one of the most important renewable sources of energy in Chile could play an important role. Against this background, the goal of this paper is the analysis of the technical potentials of biomethane as a substitute for natural gas. For the production of biomethane the anaerobic or bio-chemical (i.e. Biogas) as well as the thermo-chemical conversion pathways (i.e. Bio-SNG) are considered. The results of this analysis show that biomass converted to biomethane is a promising energy provision option for Chile and it contributes to the reduction of greenhouse gas emissions. (author)

  8. Selection of a taxonomic level for soil mapping using diversity and map purity indices: A case study from an Iranian arid region

    Science.gov (United States)

    Jafari, A.; Ayoubi, S.; Khademi, H.; Finke, P. A.; Toomanian, N.

    2013-11-01

    There is a growing demand for digital soil maps for environmental planning, modeling and management. If mapped soil classes are taken from a hierarchical taxonomic system, a question arises: which taxonomic level is most appropriate to be depicted on the map with a given sample size, available environmental covariates and the strength of predictive relations between covariates and the soil classes? Pedodiversity, the study and measurement of soil diversity, can be considered as a framework to analyze spatial patterns depicted on soil maps. This paper discusses the selection of the taxonomic level for soil mapping in an arid region in southeast Iran on the basis of (1) the purity of a digital soil class map derived from an artificial neural network (ANN) prediction method using environmental covariates and (2) pedodiversity indices of these soil maps. The prediction of soil classes and the calculation of diversity indices were carried out for taxonomic categories of order, suborder, great group, and subgroup. Using the feed forward back-propagation algorithm, three-layer ANNs with input, hidden and output layers were trained for soil class prediction at each category level. In most predictions, the combined use of terrain attributes and geomorphic surfaces provided the best results. When the taxonomic level changed from order to subgroup, the purity decreased, whereas the values of the diversity indices increased. The highest purity and lowest diversity are observed at the order level, indicating a good quality map in terms of its purity, but reflecting only little soil diversity, thus with a low usage potential. On the other hand, soil maps at the level of subgroup illustrate high diversity and low purity, so that the predicted map units are highly uncertain. This map is also inappropriate for users. We introduced an index combining the diversity and purity which indicated that the best taxonomic level for soil mapping in the study area is the great group, with

  9. COVARIATION BIAS AND THE RETURN OF FEAR

    NARCIS (Netherlands)

    de Jong, Peter; VANDENHOUT, MA; MERCKELBACH, H

    1995-01-01

    Several studies have indicated that phobic fear is accompanied by a covariation bias, i.e. that phobic Ss tend to overassociate fear relevant stimuli and aversive outcomes. Such a covariation bias seems to be a fairly direct and powerful way to confirm danger expectations and enhance fear. Therefore

  10. On the Origin of Gravitational Lorentz Covariance

    CERN Document Server

    Khoury, Justin; Tolley, Andrew J

    2013-01-01

    We provide evidence that general relativity is the unique spatially covariant effective field theory of the transverse, traceless graviton degrees of freedom. The Lorentz covariance of general relativity, having not been assumed in our analysis, is thus plausibly interpreted as an accidental or emergent symmetry of the gravitational sector.

  11. Covariant derivative of fermions and all that

    CERN Document Server

    Shapiro, Ilya L

    2016-01-01

    We present detailed pedagogical derivation of covariant derivative of fermions and some related expressions, including commutator of covariant derivatives and energy-momentum tensor of a free Dirac field. The text represents a part of the initial chapter of a one-semester course on semiclassical gravity.

  12. Covariance structure models of expectancy.

    Science.gov (United States)

    Henderson, M J; Goldman, M S; Coovert, M D; Carnevalla, N

    1994-05-01

    Antecedent variables under the broad categories of genetic, environmental and cultural influences have been linked to the risk for alcohol abuse. Such risk factors have not been shown to result in high correlations with alcohol consumption and leave unclear an understanding of the mechanism by which these variables lead to increased risk. This study employed covariance structure modeling to examine the mediational influence of stored information in memory about alcohol, alcohol expectancies in relation to two biologically and environmentally driven antecedent variables, family history of alcohol abuse and a sensation-seeking temperament in a college population. We also examined the effect of criterion contamination on the relationship between sensation-seeking and alcohol consumption. Results indicated that alcohol expectancy acts as a significant, partial mediator of the relationship between sensation-seeking and consumption, that family history of alcohol abuse is not related to drinking outcome and that overlap in items on sensation-seeking and alcohol consumption measures may falsely inflate their relationship.

  13. Acuicultura Insostenible en Chile (Unsustainable aquaculture in Chile

    Directory of Open Access Journals (Sweden)

    Sommer, Marcos

    2009-03-01

    Full Text Available ResumenLa acuicultura en Chile sólo será alternativa a la pesca si se consigue llevar su producción a parámetros de sostenibilidad, no solamente económica sino, fundamentalmente, ambiental. Con un esfuerzo dirigido hacia medidas legislativas y de control, e investigación aplicada, podríamos acercarnos a una acuicultura ambientalmente sostenible.

  14. Lactobacillus species: taxonomic complexity and controversial susceptibilities.

    Science.gov (United States)

    Goldstein, Ellie J C; Tyrrell, Kerin L; Citron, Diane M

    2015-05-15

    The genus Lactobacillus is a taxonomically complex and is composed of over 170 species that cannot be easily differentiated phenotypically and often require molecular identification. Although they are part of the normal human gastrointestinal and vaginal flora, they can also be occasional human pathogens. They are extensively used in a variety of commercial products including probiotics. Their antimicrobial susceptibilities are poorly defined in part because of their taxonomic complexity and are compounded by the different methods recommended by Clinical Laboratory Standards Institute and International Dairy Foundation. Their use as probiotics for prevention of Clostridium difficile infection is prevalent among consumers worldwide but raises the question of will the use of any concurrent antibiotic effect their ability to survive. Lactobacillus species are generally acid resistant and are able to survive ingestion. They are generally resistant to metronidazole, aminoglycosides and ciprofloxacin with L. acidophilus being susceptible to penicillin and vancomycin, whereas L. rhamnosus and L. casei are resistant to metronidazole and vancomycin.

  15. FANTOM: Functional and taxonomic analysis of metagenomes

    Directory of Open Access Journals (Sweden)

    Sanli Kemal

    2013-02-01

    Full Text Available Abstract Background Interpretation of quantitative metagenomics data is important for our understanding of ecosystem functioning and assessing differences between various environmental samples. There is a need for an easy to use tool to explore the often complex metagenomics data in taxonomic and functional context. Results Here we introduce FANTOM, a tool that allows for exploratory and comparative analysis of metagenomics abundance data integrated with metadata information and biological databases. Importantly, FANTOM can make use of any hierarchical database and it comes supplied with NCBI taxonomic hierarchies as well as KEGG Orthology, COG, PFAM and TIGRFAM databases. Conclusions The software is implemented in Python, is platform independent, and is available at http://www.sysbio.se/Fantom.

  16. A Falsification of the Citation Impediment in the Taxonomic Literature

    Science.gov (United States)

    Steiner, Florian M.; Pautasso, Marco; Zettel, Herbert; Moder, Karl; Arthofer, Wolfgang; Schlick-Steiner, Birgit C.

    2015-01-01

    Current science evaluation still relies on citation performance, despite criticisms of purely bibliometric research assessments. Biological taxonomy suffers from a drain of knowledge and manpower, with poor citation performance commonly held as one reason for this impediment. But is there really such a citation impediment in taxonomy? We compared the citation numbers of 306 taxonomic and 2291 non-taxonomic research articles (2009–2012) on mosses, orchids, ciliates, ants, and snakes, using Web of Science (WoS) and correcting for journal visibility. For three of the five taxa, significant differences were absent in citation numbers between taxonomic and non-taxonomic papers. This was also true for all taxa combined, although taxonomic papers received more citations than non-taxonomic ones. Our results show that, contrary to common belief, taxonomic contributions do not generally reduce a journal's citation performance and might even increase it. The scope of many journals rarely featuring taxonomy would allow editors to encourage a larger number of taxonomic submissions. Moreover, between 1993 and 2012, taxonomic publications accumulated faster than those from all biological fields. However, less than half of the taxonomic studies were published in journals in WoS. Thus, editors of highly visible journals inviting taxonomic contributions could benefit from taxonomy's strong momentum. The taxonomic output could increase even more than at its current growth rate if: (i) taxonomists currently publishing on other topics returned to taxonomy and (ii) non-taxonomists identifying the need for taxonomic acts started publishing these, possibly in collaboration with taxonomists. Finally, considering the high number of taxonomic papers attracted by the journal Zootaxa, we expect that the taxonomic community would indeed use increased chances of publishing in WoS indexed journals. We conclude that taxonomy's standing in the present citation-focused scientific landscape could

  17. The covariate-adjusted frequency plot.

    Science.gov (United States)

    Holling, Heinz; Böhning, Walailuck; Böhning, Dankmar; Formann, Anton K

    2016-04-01

    Count data arise in numerous fields of interest. Analysis of these data frequently require distributional assumptions. Although the graphical display of a fitted model is straightforward in the univariate scenario, this becomes more complex if covariate information needs to be included into the model. Stratification is one way to proceed, but has its limitations if the covariate has many levels or the number of covariates is large. The article suggests a marginal method which works even in the case that all possible covariate combinations are different (i.e. no covariate combination occurs more than once). For each covariate combination the fitted model value is computed and then summed over the entire data set. The technique is quite general and works with all count distributional models as well as with all forms of covariate modelling. The article provides illustrations of the method for various situations and also shows that the proposed estimator as well as the empirical count frequency are consistent with respect to the same parameter.

  18. Socialisme i Chile efter Pinochet

    DEFF Research Database (Denmark)

    Cristoffanini, Pablo Rolando

    2008-01-01

    Chile bliver ofte præsenteret som et paradigme for resten af det latinamerikanske kontinent: Et land med høj økonomisk vækst og politisk stabilitet. Landet har endda haft to socialistiske præsidenter siden 2000, den sidste den første kvindelige præsident. Succeshistorien har en bagside: De...... socialistiske regeringer har accepteret et begrænset demokrati og videreført en nyliberal økonomisk politik, der har bragt dem på konfrontationskurs med massebevægelserne og isoleret Chile fra de andre lande i regionen, der søger integration og gensidig støøte. Udgivelsesdato: Februar...

  19. Area Handbook Series: Chile: A Country Study

    Science.gov (United States)

    1982-05-01

    encomiendas , or trusteeships. Enco- menderos (those who received encomiendas ) in turn controlled the Indians. In Chile, however, there were too few...Indians to operate an encomienda system to support the many Spaniards who soon arrived-nor was there sufficient gold and silver for the Indians to pay...provided a con- 7 Chile: A Country Study venient rationale for capturing and enslaving Indians to fill the needs of the encomiendas in central Chile

  20. Forecasting Covariance Matrices: A Mixed Frequency Approach

    DEFF Research Database (Denmark)

    Halbleib, Roxana; Voev, Valeri

    This paper proposes a new method for forecasting covariance matrices of financial returns. The model mixes volatility forecasts from a dynamic model of daily realized volatilities estimated with high-frequency data with correlation forecasts based on daily data. This new approach allows...... for flexible dependence patterns for volatilities and correlations, and can be applied to covariance matrices of large dimensions. The separate modeling of volatility and correlation forecasts considerably reduces the estimation and measurement error implied by the joint estimation and modeling of covariance...... matrix dynamics. Our empirical results show that the new mixing approach provides superior forecasts compared to multivariate volatility specifications using single sources of information....

  1. Estimation of Low-Rank Covariance Function

    OpenAIRE

    Koltchinskii, Vladimir; Lounici, Karim; Tsybakov, Alexander B.

    2015-01-01

    We consider the problem of estimating a low rank covariance function $K(t,u)$ of a Gaussian process $S(t), t\\in [0,1]$ based on $n$ i.i.d. copies of $S$ observed in a white noise. We suggest a new estimation procedure adapting simultaneously to the low rank structure and the smoothness of the covariance function. The new procedure is based on nuclear norm penalization and exhibits superior performances as compared to the sample covariance function by a polynomial factor in the sample size $n$...

  2. Nuevas evidencias acerca de la presencia de Stegomastodon platensisStegomastodon platensis Ameghino, 1888, Proboscidea: Gomphotheriidae, en el Pleistoceno tardío de Chile central

    Directory of Open Access Journals (Sweden)

    Labarca, R.

    2016-06-01

    Full Text Available This paper contextualizes, describes and taxonomically assigned cranial and dental Gomphotheriidae materials from the El Trebal 1, late Pleistocene form central Chile. Starting from metric and morphological variables fossils are included in Stegomastodon platensisStegomastodon platensis. Taxonomic implications of this finding as well as some regional paleoenvironmental history are discussed.El presente trabajo contextualiza, describe, y asigna taxonómicamente los materiales craneales y dentales de Gomphotheriidae provenientes del sitio El Trebal 1, Pleistoceno tardío de Chile central. A partir de variables métricas y morfológicas los fósiles son incluidos en Stegomastodon platensisStegomastodon platensis. Se discuten las implicancias taxonómicas de este hallazgo así como algunos antecedentes paleoambientales regionales.

  3. Conformally covariant parametrizations for relativistic initial data

    Science.gov (United States)

    Delay, Erwann

    2017-01-01

    We revisit the Lichnerowicz-York method, and an alternative method of York, in order to obtain some conformally covariant systems. This type of parametrization is certainly more natural for non constant mean curvature initial data.

  4. Covariant Quantization with Extended BRST Symmetry

    CERN Document Server

    Geyer, B; Lavrov, P M

    1999-01-01

    A short rewiev of covariant quantization methods based on BRST-antiBRST symmetry is given. In particular problems of correct definition of Sp(2) symmetric quantization scheme known as triplectic quantization are considered.

  5. Functional CLT for sample covariance matrices

    CERN Document Server

    Bai, Zhidong; Zhou, Wang; 10.3150/10-BEJ250

    2010-01-01

    Using Bernstein polynomial approximations, we prove the central limit theorem for linear spectral statistics of sample covariance matrices, indexed by a set of functions with continuous fourth order derivatives on an open interval including $[(1-\\sqrt{y})^2,(1+\\sqrt{y})^2]$, the support of the Mar\\u{c}enko--Pastur law. We also derive the explicit expressions for asymptotic mean and covariance functions.

  6. Covariant Hamilton equations for field theory

    Energy Technology Data Exchange (ETDEWEB)

    Giachetta, Giovanni [Department of Mathematics and Physics, University of Camerino, Camerino (Italy); Mangiarotti, Luigi [Department of Mathematics and Physics, University of Camerino, Camerino (Italy)]. E-mail: mangiaro@camserv.unicam.it; Sardanashvily, Gennadi [Department of Theoretical Physics, Physics Faculty, Moscow State University, Moscow (Russian Federation)]. E-mail: sard@grav.phys.msu.su

    1999-09-24

    We study the relations between the equations of first-order Lagrangian field theory on fibre bundles and the covariant Hamilton equations on the finite-dimensional polysymplectic phase space of covariant Hamiltonian field theory. If a Lagrangian is hyperregular, these equations are equivalent. A degenerate Lagrangian requires a set of associated Hamiltonian forms in order to exhaust all solutions of the Euler-Lagrange equations. The case of quadratic degenerate Lagrangians is studied in detail. (author)

  7. Covariant action for type IIB supergravity

    Science.gov (United States)

    Sen, Ashoke

    2016-07-01

    Taking clues from the recent construction of the covariant action for type II and heterotic string field theories, we construct a manifestly Lorentz covariant action for type IIB supergravity, and discuss its gauge fixing maintaining manifest Lorentz invariance. The action contains a (non-gravitating) free 4-form field besides the usual fields of type IIB supergravity. This free field, being completely decoupled from the interacting sector, has no physical consequence.

  8. Economical Phase-Covariant Cloning of Qudits

    CERN Document Server

    Buscemi, F; Macchiavello, C; Buscemi, Francesco; Ariano, Giacomo Mauro D'; Macchiavello, Chiara

    2004-01-01

    We derive the optimal $N\\to M$ phase-covariant quantum cloning for equatorial states in dimension $d$ with $M=kd+N$, $k$ integer. The cloning maps are optimal for both global and single-qudit fidelity. The map is achieved by an ``economical'' cloning machine, which works without ancilla. The connection between optimal phase-covariant cloning and optimal multi-phase estimation is finally established.

  9. Covariate analysis of bivariate survival data

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, L.E.

    1992-01-01

    The methods developed are used to analyze the effects of covariates on bivariate survival data when censoring and ties are present. The proposed method provides models for bivariate survival data that include differential covariate effects and censored observations. The proposed models are based on an extension of the univariate Buckley-James estimators which replace censored data points by their expected values, conditional on the censoring time and the covariates. For the bivariate situation, it is necessary to determine the expectation of the failure times for one component conditional on the failure or censoring time of the other component. Two different methods have been developed to estimate these expectations. In the semiparametric approach these expectations are determined from a modification of Burke's estimate of the bivariate empirical survival function. In the parametric approach censored data points are also replaced by their conditional expected values where the expected values are determined from a specified parametric distribution. The model estimation will be based on the revised data set, comprised of uncensored components and expected values for the censored components. The variance-covariance matrix for the estimated covariate parameters has also been derived for both the semiparametric and parametric methods. Data from the Demographic and Health Survey was analyzed by these methods. The two outcome variables are post-partum amenorrhea and breastfeeding; education and parity were used as the covariates. Both the covariate parameter estimates and the variance-covariance estimates for the semiparametric and parametric models will be compared. In addition, a multivariate test statistic was used in the semiparametric model to examine contrasts. The significance of the statistic was determined from a bootstrap distribution of the test statistic.

  10. Representations of Inverse Covariances by Differential Operators

    Institute of Scientific and Technical Information of China (English)

    Qin XU

    2005-01-01

    In the cost function of three- or four-dimensional variational data assimilation, each term is weighted by the inverse of its associated error covariance matrix and the background error covariance matrix is usually much larger than the other covariance matrices. Although the background error covariances are traditionally normalized and parameterized by simple smooth homogeneous correlation functions, the covariance matrices constructed from these correlation functions are often too large to be inverted or even manipulated. It is thus desirable to find direct representations of the inverses of background errorcorrelations. This problem is studied in this paper. In particular, it is shown that the background term can be written into ∫ dx|Dv(x)|2, that is, a squared L2 norm of a vector differential operator D, called the D-operator, applied to the field of analysis increment v(x). For autoregressive correlation functions, the Doperators are of finite orders. For Gaussian correlation functions, the D-operators are of infinite order. For practical applications, the Gaussian D-operators must be truncated to finite orders. The truncation errors are found to be small even when the Gaussian D-operators are truncated to low orders. With a truncated D-operator, the background term can be easily constructed with neither inversion nor direct calculation of the covariance matrix. D-operators are also derived for non-Gaussian correlations and transformed into non-isotropic forms.

  11. Spatio-temporal modelling for assessing air pollution in Santiago de Chile

    Science.gov (United States)

    Nicolis, Orietta; Camaño, Christian; Mařın, Julio C.; Sahu, Sujit K.

    2017-01-01

    In this work, we propose a space-time approach for studying the PM2.5 concentration in the city of Santiago de Chile. In particular, we apply the autoregressive hierarchical model proposed by [1] using the PM2.5 observations collected by a monitoring network as a response variable and numerical weather forecasts from the Weather Research and Forecasting (WRF) model as covariate together with spatial and temporal (periodic) components. The approach is able to provide short-term spatio-temporal predictions of PM2.5 concentrations on a fine spatial grid (at 1km × 1km horizontal resolution.)

  12. Bacterial phospholipide antigens and their taxonomic significance.

    Science.gov (United States)

    Karalnik, B V; Razbash, M P; Akhmetova, E A

    1981-01-01

    The investigation of interrelationships between the phospholipides of various microorganisms (33 strains of corynebacteria, mycobacteria and staphylococci) using crossed antibody neutralization reactions with phospholipide antigenic erythrocyte diagnostic was used for the assessment of the degree of antigenic propinquity and antigenic differences between the phospholipides of bacteria of the same species, genus, and of different genera. The role of the determinants of the corresponding (their own) and "foreign" genera in the antigenic differences between the phospholipides of the microorganisms investigated was established. On the basis of the results obtained the conclusion has been drawn that the method of assessment of antigenic interrelationships between phospholipides can be used for the study of some taxonomic problems.

  13. Taxonomical developments in the family Polyomaviridae.

    Science.gov (United States)

    Johne, Reimar; Buck, Christopher B; Allander, Tobias; Atwood, Walter J; Garcea, Robert L; Imperiale, Michael J; Major, Eugene O; Ramqvist, Torbjorn; Norkin, Leonard C

    2011-09-01

    The Polyomaviridae Study Group of the International Committee on Taxonomy of Viruses (ICTV) has recommended several taxonomical revisions, as follows: The family Polyomaviridae, which is currently constituted as a single genus (Polyomavirus), will be comprised of three genera: two containing mammalian viruses and one containing avian viruses. The two mammalian genera will be designated Orthopolyomavirus and Wukipolyomavirus, and the avian genus will be named Avipolyomavirus. These genera will be created by the redistribution of species from the current single genus (Polyomavirus) and by the inclusion of several new species. In addition, the names of several species will be changed to reflect current usage.

  14. Rising Expectations in Brazil and Chile

    Science.gov (United States)

    Elacqua, Gregory; Alves, Fatima

    2014-01-01

    Two themes connect Brazil and Chile: one is economic success; the other is social unrest. Protests rocked cities across Brazil in June 2013, and in Chile, recent student protests turned violent. Yet living conditions in both nations are better now than they've ever been. Successful economic and social reforms over the last two decades have led to…

  15. Rising Expectations in Brazil and Chile

    Science.gov (United States)

    Elacqua, Gregory; Alves, Fatima

    2014-01-01

    Two themes connect Brazil and Chile: one is economic success; the other is social unrest. Protests rocked cities across Brazil in June 2013, and in Chile, recent student protests turned violent. Yet living conditions in both nations are better now than they've ever been. Successful economic and social reforms over the last two decades have…

  16. Revisión y estudio de los restos fósiles de mastodontes de Chile (Gomphotheriidae: Cuvieronius hyodon, Pleistoceno superior

    Directory of Open Access Journals (Sweden)

    Alberdi, M. T.

    2000-08-01

    Full Text Available Mastodont fossil remains from Chile are described and discussed from a taxonomic point of view. A single species must be considered: Cuvieronius hyodon (Fischer for the Late Pleistocene of Chile. Some of its characteristics are analyzed and compared with those of other mastodons from different localities in South America. Paleoecological considerations are revised and potential migration routes from the north, towards the Chilean territory, are also discussed.Se describen y sitúan taxonómicamente los restos de mastodontes de las localidades chilenas. Se identifica una sola forma: Cuvieronius hyodon (Fischer para el Pleistoceno superior en Chile. Se analizan sus características y se comparan con aquellas de mastodontes de otras localidades de América del Sur. Asimismo se revisan consideraciones de tipo paleoecológico, y se discuten sus probables vías de migración desde el norte hacia el territorio chileno.

  17. Rotational Study of Ambiguous Taxonomic Classified Asteroids

    Science.gov (United States)

    Linder, Tyler R.; Sanchez, Rick; Wuerker, Wolfgang; Clayson, Timothy; Giles, Tucker

    2017-01-01

    The Sloan Digital Sky Survey (SDSS) moving object catalog (MOC4) provided the largest ever catalog of asteroid spectrophotometry observations. Carvano et al. (2010), while analyzing MOC4, discovered that individual observations of asteroids which were observed multiple times did not classify into the same photometric-based taxonomic class. A small subset of those asteroids were classified as having both the presence and absence of a 1um silicate absorption feature. If these variations are linked to differences in surface mineralogy, the prevailing assumption that an asteroid’s surface composition is predominantly homogenous would need to be reexamined. Furthermore, our understanding of the evolution of the asteroid belt, as well as the linkage between certain asteroids and meteorite types may need to be modified.This research is an investigation to determine the rotational rates of these taxonomically ambiguous asteroids. Initial questions to be answered:Do these asteroids have unique or nonstandard rotational rates?Is there any evidence in their light curve to suggest an abnormality?Observations were taken using PROMPT6 a 0.41-m telescope apart of the SKYNET network at Cerro Tololo Inter-American Observatory (CTIO). Observations were calibrated and analyzed using Canopus software. Initial results will be presented at AAS.

  18. Accurate taxonomic assignment of short pyrosequencing reads.

    Science.gov (United States)

    Clemente, José C; Jansson, Jesper; Valiente, Gabriel

    2010-01-01

    Ambiguities in the taxonomy dependent assignment of pyrosequencing reads are usually resolved by mapping each read to the lowest common ancestor in a reference taxonomy of all those sequences that match the read. This conservative approach has the drawback of mapping a read to a possibly large clade that may also contain many sequences not matching the read. A more accurate taxonomic assignment of short reads can be made by mapping each read to the node in the reference taxonomy that provides the best precision and recall. We show that given a suffix array for the sequences in the reference taxonomy, a short read can be mapped to the node of the reference taxonomy with the best combined value of precision and recall in time linear in the size of the taxonomy subtree rooted at the lowest common ancestor of the matching sequences. An accurate taxonomic assignment of short reads can thus be made with about the same efficiency as when mapping each read to the lowest common ancestor of all matching sequences in a reference taxonomy. We demonstrate the effectiveness of our approach on several metagenomic datasets of marine and gut microbiota.

  19. Antarctica: Chile’s Claim,

    Science.gov (United States)

    1987-01-01

    any decree, war, or treaty. The report, Geographic and Hydrographic His- tory of the Kingdom of Chile, whose author was Gov- ernor Manuel Amat y...men include Lieu- tenants Ponce and Torrealba of the Chilean Army and Captain Ariel Gonzalez and Corporal Rojas of the Chilean Navy. The interest in...Land, 62 of, 28-30, 36-38, Aguirre Cerda, Pedro, 82, 76, 88 93,96 "stages of growth" of, Alderete, Jeronimo de, 91 31-32 Amat y Jumient, Manuel

  20. [Antimicrobial susceptibility in Chile 2012].

    Science.gov (United States)

    Cifuentes-D, Marcela; Silva, Francisco; García, Patricia; Bello, Helia; Briceño, Isabel; Calvo-A, Mario; Labarca, Jaime

    2014-04-01

    Bacteria antimicrobial resistance is an uncontrolled public health problem that progressively increases its magnitude and complexity. The Grupo Colaborativo de Resistencia, formed by a join of experts that represent 39 Chilean health institutions has been concerned with bacteria antimicrobial susceptibility in our country since 2008. In this document we present in vitro bacterial susceptibility accumulated during year 2012 belonging to 28 national health institutions that represent about 36% of hospital discharges in Chile. We consider of major importance to report periodically bacteria susceptibility so to keep the medical community updated to achieve target the empirical antimicrobial therapies and the control measures and prevention of the dissemination of multiresistant strains.

  1. Lorentz covariance of loop quantum gravity

    CERN Document Server

    Rovelli, Carlo

    2010-01-01

    The kinematics of loop gravity can be given a manifestly Lorentz-covariant formulation: the conventional SU(2)-spin-network Hilbert space can be mapped to a space K of SL(2,C) functions, where Lorentz covariance is manifest. K can be described in terms of a certain subset of the "projected" spin networks studied by Livine, Alexandrov and Dupuis. It is formed by SL(2,C) functions completely determined by their restriction on SU(2). These are square-integrable in the SU(2) scalar product, but not in the SL(2,C) one. Thus, SU(2)-spin-network states can be represented by Lorentz-covariant SL(2,C) functions, as two-component photons can be described in the Lorentz-covariant Gupta-Bleuler formalism. As shown by Wolfgang Wieland in a related paper, this manifestly Lorentz-covariant formulation can also be directly obtained from canonical quantization. We show that the spinfoam dynamics of loop quantum gravity is locally SL(2,C)-invariant in the bulk, and yields states that are preciseley in K on the boundary. This c...

  2. Wishart distributions for decomposable covariance graph models

    CERN Document Server

    Khare, Kshitij; 10.1214/10-AOS841

    2011-01-01

    Gaussian covariance graph models encode marginal independence among the components of a multivariate random vector by means of a graph $G$. These models are distinctly different from the traditional concentration graph models (often also referred to as Gaussian graphical models or covariance selection models) since the zeros in the parameter are now reflected in the covariance matrix $\\Sigma$, as compared to the concentration matrix $\\Omega =\\Sigma^{-1}$. The parameter space of interest for covariance graph models is the cone $P_G$ of positive definite matrices with fixed zeros corresponding to the missing edges of $G$. As in Letac and Massam [Ann. Statist. 35 (2007) 1278--1323], we consider the case where $G$ is decomposable. In this paper, we construct on the cone $P_G$ a family of Wishart distributions which serve a similar purpose in the covariance graph setting as those constructed by Letac and Massam [Ann. Statist. 35 (2007) 1278--1323] and Dawid and Lauritzen [Ann. Statist. 21 (1993) 1272--1317] do in ...

  3. Cross-covariance functions for multivariate geostatistics

    KAUST Repository

    Genton, Marc G.

    2015-05-01

    Continuously indexed datasets with multiple variables have become ubiquitous in the geophysical, ecological, environmental and climate sciences, and pose substantial analysis challenges to scientists and statisticians. For many years, scientists developed models that aimed at capturing the spatial behavior for an individual process; only within the last few decades has it become commonplace to model multiple processes jointly. The key difficulty is in specifying the cross-covariance function, that is, the function responsible for the relationship between distinct variables. Indeed, these cross-covariance functions must be chosen to be consistent with marginal covariance functions in such a way that the second-order structure always yields a nonnegative definite covariance matrix. We review the main approaches to building cross-covariance models, including the linear model of coregionalization, convolution methods, the multivariate Matérn and nonstationary and space-time extensions of these among others. We additionally cover specialized constructions, including those designed for asymmetry, compact support and spherical domains, with a review of physics-constrained models. We illustrate select models on a bivariate regional climate model output example for temperature and pressure, along with a bivariate minimum and maximum temperature observational dataset; we compare models by likelihood value as well as via cross-validation co-kriging studies. The article closes with a discussion of unsolved problems. © Institute of Mathematical Statistics, 2015.

  4. Activities on covariance estimation in Japanese Nuclear Data Committee

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Keiichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    Described are activities on covariance estimation in the Japanese Nuclear Data Committee. Covariances are obtained from measurements by using the least-squares methods. A simultaneous evaluation was performed to deduce covariances of fission cross sections of U and Pu isotopes. A code system, KALMAN, is used to estimate covariances of nuclear model calculations from uncertainties in model parameters. (author)

  5. Accurate covariance estimation of galaxy-galaxy weak lensing: limitations of jackknife covariance

    CERN Document Server

    Shirasaki, Masato; Miyatake, Hironao; Takahashi, Ryuichi; Hamana, Takashi; Nishimichi, Takahiro; Murata, Ryoma

    2016-01-01

    We develop a method to simulate galaxy-galaxy weak lensing by utilizing all-sky, light-cone simulations. We populate a real catalog of source galaxies into a light-cone simulation realization, simulate the lensing effect on each galaxy, and then identify lensing halos that are considered to host galaxies or clusters of interest. We use the mock catalog to study the error covariance matrix of galaxy-galaxy weak lensing and find that the super-sample covariance (SSC), which arises from density fluctuations with length scales comparable with or greater than a size of survey area, gives a dominant source of the sample variance. We then compare the full covariance with the jackknife (JK) covariance, the method that estimates the covariance from the resamples of the data itself. We show that, although the JK method gives an unbiased estimator of the covariance in the shot noise or Gaussian regime, it always over-estimates the true covariance in the sample variance regime, because the JK covariance turns out to be a...

  6. Progress on Nuclear Data Covariances: AFCI-1.2 Covariance Library

    Energy Technology Data Exchange (ETDEWEB)

    Oblozinsky,P.; Oblozinsky,P.; Mattoon,C.M.; Herman,M.; Mughabghab,S.F.; Pigni,M.T.; Talou,P.; Hale,G.M.; Kahler,A.C.; Kawano,T.; Little,R.C.; Young,P.G

    2009-09-28

    Improved neutron cross section covariances were produced for 110 materials including 12 light nuclei (coolants and moderators), 78 structural materials and fission products, and 20 actinides. Improved covariances were organized into AFCI-1.2 covariance library in 33-energy groups, from 10{sup -5} eV to 19.6 MeV. BNL contributed improved covariance data for the following materials: {sup 23}Na and {sup 55}Mn where more detailed evaluation was done; improvements in major structural materials {sup 52}Cr, {sup 56}Fe and {sup 58}Ni; improved estimates for remaining structural materials and fission products; improved covariances for 14 minor actinides, and estimates of mubar covariances for {sup 23}Na and {sup 56}Fe. LANL contributed improved covariance data for {sup 235}U and {sup 239}Pu including prompt neutron fission spectra and completely new evaluation for {sup 240}Pu. New R-matrix evaluation for {sup 16}O including mubar covariances is under completion. BNL assembled the library and performed basic testing using improved procedures including inspection of uncertainty and correlation plots for each material. The AFCI-1.2 library was released to ANL and INL in August 2009.

  7. A novel algorithm for establishing taxonomic relation of Chinese ontology

    Institute of Scientific and Technical Information of China (English)

    PEI Bing-zhen; CHEN Xiao-rong; HU Yi; LU Ru-zhan

    2009-01-01

    Both a general domain-independent bottom-up multi-level model and an algorithm for establishing the taxonomic relation of Chinese ontology are proposed. The model consists of extracting domain vocabularies and establishing taxonomic relation, with the consideration of characteristics unique to Chinese natural language. By establishing the semantic forests of domain vocabularies and then using the existing semantic dictionary or ma-chine-readable dictionary (MRD), the proposed algorithm can integrate these semantic forests together to estab-lish the taxonomic relation. Experimental results show that the proposed algorithm is feasible and effective in es-tablishing the integrated taxonomic relation among domain vocabularies and concepts.

  8. EL RACISMO AMBIENTAL EN CHILE

    Directory of Open Access Journals (Sweden)

    MATÍAS MEZA-LOPEHANDÍA

    2011-06-01

    Full Text Available El problema de la desigualdad en Chile ha sido abordado desde diferentes puntos de vista como la cuestión de la distribución de la riqueza o el acceso a los derechos sociales. Es este trabajo se observa el mismo problema pero desde la perspectiva recientemente esbozada por los movimientos sociales: la del racismo ambiental o la desigual distribución de los deshechos del desarrollo y el consumo. De esta manera se revisan sucintamente los principales conflictos que han surgido en el último tiempo a lo largo del país entre empresas públicas y privadas y comunidades locales y originarias. Así mismo se examinan las formas de organización que estas últimas han asumido y el estado actual de articulación entre ellas. De la revisión de la situación se concluye que estamos ante el surgimiento de un actor de nuevo tipo, que surge de las contradicciones del Chile neoliberal y que se diferencia del movimiento ecologista por vincular sus reivindicaciones a la defensa del territorio y al derecho a la autodeterminación de los pueblos.

  9. President of Chile at CERN

    CERN Multimedia

    2007-01-01

    The President of Chile, Michelle Bachelet, in the ATLAS cavern with, from left to right, Peter Jenni, ATLAS Spokesman, Vivian Heyl, CONICYT President, and Robert Aymar, CERN Director-General. Robert Aymar, CERN Director-General, and Vivian Heyl, CONICYT President, signing a cooperation agreement between CERN and Chile’s Comisión Nacional de Investigación Científica y Tecnológica (CONICYT).The President of Chile, Michelle Bachelet, paid a visit to CERN during her three-day tour of Switzerland. The charismatic Michelle Bachelet and her large delegation were greeted by the CERN Director-General and then taken to see the ATLAS experiment and the LHC. She also took time to meet the Chilean community working at CERN, comprising several physicists in the Theory Group and the ATLAS experiment. The meeting was followed by the signing of a cooperation agreement between CERN and Chile’s Comisión Nacional de Investigación Científi...

  10. TaxMan: a taxonomic database manager

    Directory of Open Access Journals (Sweden)

    Blaxter Mark

    2006-12-01

    Full Text Available Abstract Background Phylogenetic analysis of large, multiple-gene datasets, assembled from public sequence databases, is rapidly becoming a popular way to approach difficult phylogenetic problems. Supermatrices (concatenated multiple sequence alignments of multiple genes can yield more phylogenetic signal than individual genes. However, manually assembling such datasets for a large taxonomic group is time-consuming and error-prone. Additionally, sequence curation, alignment and assessment of the results of phylogenetic analysis are made particularly difficult by the potential for a given gene in a given species to be unrepresented, or to be represented by multiple or partial sequences. We have developed a software package, TaxMan, that largely automates the processes of sequence acquisition, consensus building, alignment and taxon selection to facilitate this type of phylogenetic study. Results TaxMan uses freely available tools to allow rapid assembly, storage and analysis of large, aligned DNA and protein sequence datasets for user-defined sets of species and genes. The user provides GenBank format files and a list of gene names and synonyms for the loci to analyse. Sequences are extracted from the GenBank files on the basis of annotation and sequence similarity. Consensus sequences are built automatically. Alignment is carried out (where possible, at the protein level and aligned sequences are stored in a database. TaxMan can automatically determine the best subset of taxa to examine phylogeny at a given taxonomic level. By using the stored aligned sequences, large concatenated multiple sequence alignments can be generated rapidly for a subset and output in analysis-ready file formats. Trees resulting from phylogenetic analysis can be stored and compared with a reference taxonomy. Conclusion TaxMan allows rapid automated assembly of a multigene datasets of aligned sequences for large taxonomic groups. By extracting sequences on the basis of

  11. Structural damage detection based on covariance of covariance matrix with general white noise excitation

    Science.gov (United States)

    Hui, Yi; Law, Siu Seong; Ku, Chiu Jen

    2017-02-01

    Covariance of the auto/cross-covariance matrix based method is studied for the damage identification of a structure with illustrations on its advantages and limitations. The original method is extended for structures under direct white noise excitations. The auto/cross-covariance function of the measured acceleration and its corresponding derivatives are formulated analytically, and the method is modified in two new strategies to enable successful identification with much fewer sensors. Numerical examples are adopted to illustrate the improved method, and the effects of sampling frequency and sampling duration are discussed. Results show that the covariance of covariance calculated from responses of higher order modes of a structure play an important role to the accurate identification of local damage in a structure.

  12. Covariant Lyapunov vectors for rigid disk systems.

    Science.gov (United States)

    Bosetti, Hadrien; Posch, Harald A

    2010-10-05

    We carry out extensive computer simulations to study the Lyapunov instability of a two-dimensional hard-disk system in a rectangular box with periodic boundary conditions. The system is large enough to allow the formation of Lyapunov modes parallel to the x-axis of the box. The Oseledec splitting into covariant subspaces of the tangent space is considered by computing the full set of covariant perturbation vectors co-moving with the flow in tangent space. These vectors are shown to be transversal, but generally not orthogonal to each other. Only the angle between covariant vectors associated with immediate adjacent Lyapunov exponents in the Lyapunov spectrum may become small, but the probability of this angle to vanish approaches zero. The stable and unstable manifolds are transverse to each other and the system is hyperbolic.

  13. Manifest Covariant Hamiltonian Theory of General Relativity

    CERN Document Server

    Cremaschini, Claudio

    2016-01-01

    The problem of formulating a manifest covariant Hamiltonian theory of General Relativity in the presence of source fields is addressed, by extending the so-called "DeDonder-Weyl" formalism to the treatment of classical fields in curved space-time. The theory is based on a synchronous variational principle for the Einstein equation, formulated in terms of superabundant variables. The technique permits one to determine the continuum covariant Hamiltonian structure associated with the Einstein equation. The corresponding continuum Poisson bracket representation is also determined. The theory relies on first-principles, in the sense that the conclusions are reached in the framework of a non-perturbative covariant approach, which allows one to preserve both the 4-scalar nature of Lagrangian and Hamiltonian densities as well as the gauge invariance property of the theory.

  14. A review of the non-bulimulid terrestrial Mollusca from the Region of Atacama, northern Chile

    Directory of Open Access Journals (Sweden)

    Juan Francisco Araya

    2014-04-01

    Full Text Available Terrestrial mollusca are sparsely studied in Chile and, for the first time, a formal record of the diversity of land snails in northern Chile is reported. Coastal and desertic areas in the Region of Atacama, in the border of the Atacama desert and the Pacific Ocean, were surveyed with the aim to describe the presence and distribution of this poorly known fauna. Of the fourteen species recorded, the geographic distribution records for nine species are extended, and some taxa are recorded for the first time since their original descriptions. All, except one, of the fourteen terrestrial molluscan species occurring in the area are endemic to Chile; they are all terrestrial species, most of them have a restricted geographic distribution, and none of them is currently protected by law. The results reveal that the region of Atacama has one of the most diverse terrestrial snail biodiversity in Chile, ranking only after the Juan Fernandez Archipelago. Distribution records of all the studied species and a taxonomic key are also provided.

  15. Notes on Cosmic Censorship Conjecture revisited: Covariantly

    CERN Document Server

    Hamid, Aymen I M; Maharaj, Sunil D

    2016-01-01

    In this paper we study the dynamics of the trapped region using a frame independent semi-tetrad covariant formalism for general Locally Rotationally Symmetric (LRS) class II spacetimes. We covariantly prove some important geometrical results for the apparent horizon, and state the necessary and sufficient conditions for a singularity to be locally naked. These conditions bring out, for the first time in a quantitative and transparent manner, the importance of the Weyl curvature in deforming and delaying the trapped region during continual gravitational collapse, making the central singularity locally visible.

  16. A covariant formulation of classical spinning particle

    CERN Document Server

    Cho, J H; Kim, J K; Jin-Ho Cho; Seungjoon Hyun; Jae-Kwan Kim

    1994-01-01

    Covariantly we reformulate the description of a spinning particle in terms of the which entails all possible constraints explicitly; all constraints can be obtained just from the Lagrangian. Furthermore, in this covariant reformulation, the Lorentz element is to be considered to evolve the momentum or spin component from an arbitrary fixed frame and not just from the particle rest frame. In distinction with the usual formulation, our system is directly comparable with the pseudo-classical formulation. We get a peculiar symmetry which resembles the supersymmetry of the pseudo-classical formulation.

  17. Flexible taxonomic assignment of ambiguous sequencing reads

    Directory of Open Access Journals (Sweden)

    Jansson Jesper

    2011-01-01

    Full Text Available Abstract Background To characterize the diversity of bacterial populations in metagenomic studies, sequencing reads need to be accurately assigned to taxonomic units in a given reference taxonomy. Reads that cannot be reliably assigned to a unique leaf in the taxonomy (ambiguous reads are typically assigned to the lowest common ancestor of the set of species that match it. This introduces a potentially severe error in the estimation of bacteria present in the sample due to false positives, since all species in the subtree rooted at the ancestor are implicitly assigned to the read even though many of them may not match it. Results We present a method that maps each read to a node in the taxonomy that minimizes a penalty score while balancing the relevance of precision and recall in the assignment through a parameter q. This mapping can be obtained in time linear in the number of matching sequences, because LCA queries to the reference taxonomy take constant time. When applied to six different metagenomic datasets, our algorithm produces different taxonomic distributions depending on whether coverage or precision is maximized. Including information on the quality of the reads reduces the number of unassigned reads but increases the number of ambiguous reads, stressing the relevance of our method. Finally, two measures of performance are described and results with a set of artificially generated datasets are discussed. Conclusions The assignment strategy of sequencing reads introduced in this paper is a versatile and a quick method to study bacterial communities. The bacterial composition of the analyzed samples can vary significantly depending on how ambiguous reads are assigned depending on the value of the q parameter. Validation of our results in an artificial dataset confirm that a combination of values of q produces the most accurate results.

  18. Global taxonomic diversity of living reptiles.

    Science.gov (United States)

    Pincheira-Donoso, Daniel; Bauer, Aaron M; Meiri, Shai; Uetz, Peter

    2013-01-01

    Reptiles are one of the most ecologically and evolutionarily remarkable groups of living organisms, having successfully colonized most of the planet, including the oceans and some of the harshest and more environmentally unstable ecosystems on earth. Here, based on a complete dataset of all the world's diversity of living reptiles, we analyse lineage taxonomic richness both within and among clades, at different levels of the phylogenetic hierarchy. We also analyse the historical tendencies in the descriptions of new reptile species from Linnaeus to March 2012. Although (non-avian) reptiles are the second most species-rich group of amniotes after birds, most of their diversity (96.3%) is concentrated in squamates (59% lizards, 35% snakes, and 2% amphisbaenians). In strong contrast, turtles (3.4%), crocodilians (0.3%), and tuataras (0.01%) are far less diverse. In terms of species discoveries, most turtles and crocodilians were described early, while descriptions of lizards, snakes and amphisbaenians are multimodal with respect to time. Lizard descriptions, in particular, have reached unprecedented levels during the last decade. Finally, despite such remarkably asymmetric distributions of reptile taxonomic diversity among groups, we found that the distributions of lineage richness are consistently right-skewed, with most clades (monophyletic families and genera) containing few lineages (monophyletic genera and species, respectively), while only a few have radiated greatly (notably the families Colubridae and Scincidae, and the lizard genera Anolis and Liolaemus). Therefore, such consistency in the frequency distribution of richness among clades and among phylogenetic levels suggests that the nature of reptile biodiversity is fundamentally fractal (i.e., it is scale invariant). We then compared current reptile diversity with the global reptile diversity and taxonomy known in 1980. Despite substantial differences in the taxonomies (relative to 2012), the patterns of

  19. Chile. A model mining country?; Chile. Ein Bergbau-Musterland?

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Sven [Projektbuero der Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR) und des chilenischen Geologie und Bergbaudienstes SERNAGEOMIN, Santiago de Chile (Chile). Projekt ' Grundlagen der Sanierung von Bergbaualtlasten in Chile' ; Dalheimer, Manfred [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany). Abt. Internationale Zusammenarbeit Amerika

    2009-03-19

    Chile is characterised economically and culturally by mining. The copper industry is highly important. In 2007 two thirds of export proceeds were generated solely by copper, copper concentrate and other minerals. With the increase in the price of raw materials since 2004 the state income rose considerably with the result that the national debt was offset. However, this increase was barely noticeable among the wider public. Further reasons for doubt with regards to the mining industry are that a new mining project generally not only creates jobs, but also changes local structures, competes with water utilisation and usually leaves contaminated sites. The responsible politicians and mining authorities are aware of these relationships and are drawing up corresponding laws and decrees. These include the Environmental Act, the bills for mine closures and the systematic redevelopment of old mining sites. At least voluntary commitments for current large-scale mining are in force until the bills are passed. (orig.)

  20. Chile: los mapuches y el Bicentenario Chile: Mapuches e do Bicentenario Chile: Mapuche and the Bicentennial

    Directory of Open Access Journals (Sweden)

    José Bengoa

    2011-12-01

    Full Text Available El Bicentenario de la República de Chile se conmemoró en el mes de septiembre del año 2010. Además de marcar un importante hito histórico, coincidió con un cambio político en el Gobierno del país, el que pasó de la Concertación de Partidos por la Democracia a la Alianza de partidos formada por la derecha chilena. Se cumplieron por tanto 20 años desde que en el año 1990 cambiara el Gobierno militar presidido por el general Pinochet. Ese largo tiempo, dos décadas, coincide con un período de políticas que el Estado ha implementado hacia los Pueblos Indígenas. El Proyecto “Conmemoraciones y Memorias Subalternas” ha realizado durante el año 2010 un conjunto de investigaciones de terreno y documentales tendientes a comprender del modo más objetivo y científico lo ocurrido en el período y por tanto la situación actual de las sociedades mapuches en sus complejas relaciones con la chilena.O Bicentenario da República do Chile comemorou-se no mês de Setembro do ano 2010. Junto com transformar-se num marco histórico, coincidiu com uma mudança política no Governo do país, que passou da Concertação de Partidos pela Democracia (centro-esquerda à Aliança de partidos formada pela direita chilena. Cumpriram-se por tanto 20 anos desde que em 1990 mudasse o Governo militar presidido pelo general Pinochet. Esse longo tempo, duas décadas, coincide com um período de políticas que o Estado implementou para com os Povos Indígenas. O Projeto “Comemorações e Memórias Subalternas” realizou durante o ano 2010 um conjunto de pesquisas de campo e documentais tendentes a compreender do modo mais objetivo e científico o ocorrido no período e, por tanto, a situação atual das sociedades mapuches em suas complexas relações com a chilena.The conmeration of the 200 years of the Independence of Chile was in September 2010. This year was also the political change from the Concertación de Partidos por la Democracia to the right

  1. Rodulfo Amando Philippi, el naturalista de mayor aporte al conocimiento taxonómico de la diversidad biológica de Chile

    Directory of Open Access Journals (Sweden)

    SERGIO A CASTRO

    2006-03-01

    Full Text Available Rodulfo Amando Philippi (1808-1904 es considerado uno de los naturalistas más influyentes en el desarrollo de las Ciencias Naturales en Chile. Entre las actividades científicas que desempeñó en el país está su dedicación al trabajo taxonómico y sistemático, que lo llevó a describir numerosas especies de plantas, animales y hongos. En este artículo se determina su contribución al conocimiento del patrimonio biológico de Chile, cuantificando el número y proporción de las especies actualmente válidas. De las especies descritas, 1.670 son consideradas válidas. Esta cifra equivale al 5,8 % de la diversidad biológica reconocida para Chile. Su mayor aporte se concentra en plantas vasculares, donde se encuentran vigentes 1.017 especies, que representan el 19 % de la flora vascular de Chile. Mención especial requiere el caso de algunos grupos, tales como anfibios, fasmatódeos, dermápteros y dípteros, cuya actual diversidad incluye 14, 30, 16 y 9 % de las especies de descritas por Philippi, respectivamente. De acuerdo a lo anterior y en comparación con otros taxónomos, Rodulfo Amando Philippi es el autor del mayor número de descripciones de especies válidas de la biota de ChileRodulfo Amando Philippi (1808-1904 is considered one of most influential in the development of natural sciences in Chile. Among his scientific endeavors, he contributed taxonomic descriptions of the biological diversity of Chile, encompassing organisms in three living kingdoms: plants, animals and fungi. In this article we examine his contribution to the knowledge of the biological wealth of Chile, quantifying the number and proportion of current valid species he described. Our findings indicate that Philippi described 1,670 valid species, equivalent to 5.8 % of the recognized biological diversity for Chile. His greatest contributions were in vascular plants with 1,017 species descriptions, which represent 19 % of the vascular flora of Chile. Special

  2. Global pedodiversity, taxonomic distance, and the World Reference Base

    NARCIS (Netherlands)

    Minasny, B.; McBratney, A.B.; Hartemink, A.E.

    2010-01-01

    This paper discusses the study of taxonomic distance and pedodiversity by (1) deriving taxonomic distances for the World Reference Base for Soil Resources (WRB), (2) calculating pedodiversity indices at the global scale using the soil map of the world at a scale 1:25M, and (3) comparing traditional

  3. Preschool Children's Taxonomic Knowledge of Animal Species

    Science.gov (United States)

    Allen, Michael

    2015-01-01

    Although taxonomic proficiency is a prerequisite for understanding ideas central to biology, previous research has established that learners frequently misclassify animals by not following the tenets of accepted taxonomic rubrics. This has immediate relevance with the recently revised English National Curriculum now requiring concepts of animal…

  4. Nuevos registros de Orchestoidea tuberculata Nicolet 1849 (Amphipoda, Talitridae, en la costa de Chile New records of Orchestoidea tuberculata Nicolet 1849 (Amphipoda, Talitridae, from the coast of Chile

    Directory of Open Access Journals (Sweden)

    Luisa Baessolo

    2010-08-01

    Full Text Available Se reportan nuevas localidades para el anfípodo talítrido Orchestoidea tuberculata Nicolet 1849 en playas arenosas de la costa Chilena, extendiéndose el límite sur de distribución de la especie hasta el mar interior de la región de Aysén. Además, se discute la necesidad de intensificar los estudios taxonómicos con el objeto de descartar la presencia de más de una especie en el género.We report new localities of the talitrid amphipod Orchestoidea tuberculata Nicolet 1849 in sand beaches from the Chilean coast, extending the southern distributional limit of the species to the inner sea of Aysen Region, Chile. Besides, we discuss the need for more taxonomic studies, to exclude the presence of more than one species in the genus.

  5. Molecular characterization of endophytic fungi associated with the roots of Chenopodium quinoa inhabiting the Atacama Desert, Chile.

    Science.gov (United States)

    González-Teuber, M; Vilo, C; Bascuñán-Godoy, L

    2017-03-01

    Plant roots can be highly colonized by fungal endophytes. This seems to be of particular importance for the survival of plants inhabiting stressful habitats. This study focused on the Identification of the fungal endophytic community associated with the roots of quinoa plants (Chenopodium quinoa) growing near the salt lakes of the Atacama Desert, Chile. One hundred endophytic fungi were isolated from healthy quinoa roots, and the internal transcribed spacer (ITS) region was sequenced for phylogenetic and taxonomic analysis. The isolates were classified into eleven genera and 21 distinct operational taxonomic units (OTUs). Despite a relatively high diversity of root endophytic fungi associated with quinoa plants, the fungal community was dominated by only the Ascomycota phyla. In addition, the most abundant genera were Penicillium, Phoma and Fusarium, which are common endophytes reported in plant roots. This study shows that roots of C. quinoa harbor a diverse group of endophytic fungi. Potential roles of these fungi in plant host tolerance to stressful conditions are discussed.

  6. Covariant Photon Quantization in the SME

    CERN Document Server

    Colladay, Don

    2013-01-01

    The Gupta Bleuler quantization procedure is applied to the SME photon sector. A direct application of the method to the massless case fails due to an unavoidable incompleteness in the polarization states. A mass term can be included into the photon lagrangian to rescue the quantization procedure and maintain covariance.

  7. Covariance of noncommutative Grassmann star product

    OpenAIRE

    Daoud, M.

    2004-01-01

    Using the Coherent states of many fermionic degrees of freedom labeled by Gra\\ss mann variables, we introduce the noncommutative (precisely non anticommutative) Gra\\ss mann star product. The covariance of star product under unitary transformations, particularly canonical ones, is studied. The super star product, based on supercoherent states of supersymmetric harmonic oscillator, is also considered.

  8. Covariant derivative expansion of the heat kernel

    Energy Technology Data Exchange (ETDEWEB)

    Salcedo, L.L. [Universidad de Granada, Departamento de Fisica Moderna, Granada (Spain)

    2004-11-01

    Using the technique of labeled operators, compact explicit expressions are given for all traced heat kernel coefficients containing zero, two, four and six covariant derivatives, and for diagonal coefficients with zero, two and four derivatives. The results apply to boundaryless flat space-times and arbitrary non-Abelian scalar and gauge background fields. (orig.)

  9. The Massless Spectrum of Covariant Superstrings

    CERN Document Server

    Grassi, P A; van Nieuwenhuizen, P

    2002-01-01

    We obtain the correct cohomology at any ghost number for the open and closed covariant superstring, quantized by an approach which we recently developed. We define physical states by the usual condition of BRST invariance and a new condition involving a new current which is related to a grading of the underlying affine Lie algebra.

  10. Optimal covariate designs theory and applications

    CERN Document Server

    Das, Premadhis; Mandal, Nripes Kumar; Sinha, Bikas Kumar

    2015-01-01

    This book primarily addresses the optimality aspects of covariate designs. A covariate model is a combination of ANOVA and regression models. Optimal estimation of the parameters of the model using a suitable choice of designs is of great importance; as such choices allow experimenters to extract maximum information for the unknown model parameters. The main emphasis of this monograph is to start with an assumed covariate model in combination with some standard ANOVA set-ups such as CRD, RBD, BIBD, GDD, BTIBD, BPEBD, cross-over, multi-factor, split-plot and strip-plot designs, treatment control designs, etc. and discuss the nature and availability of optimal covariate designs. In some situations, optimal estimations of both ANOVA and the regression parameters are provided. Global optimality and D-optimality criteria are mainly used in selecting the design. The standard optimality results of both discrete and continuous set-ups have been adapted, and several novel combinatorial techniques have been applied for...

  11. Approximate methods for derivation of covariance data

    Energy Technology Data Exchange (ETDEWEB)

    Tagesen, S. [Vienna Univ. (Austria). Inst. fuer Radiumforschung und Kernphysik; Larson, D.C. [Oak Ridge National Lab., TN (United States)

    1992-12-31

    Several approaches for the derivation of covariance information for evaluated nuclear data files (EFF2 and ENDF/B-VI) have been developed and used at IRK and ORNL respectively. Considerations, governing the choice of a distinct method depending on the quantity and quality of available data are presented, advantages/disadvantages are discussed and examples of results are given.

  12. Covariance of the selfdual vector model

    OpenAIRE

    2004-01-01

    The Poisson algebra between the fields involved in the vectorial selfdual action is obtained by means of the reduced action. The conserved charges associated with the invariance under the inhomogeneous Lorentz group are obtained and its action on the fields. The covariance of the theory is proved using the Schwinger-Dirac algebra. The spin of the excitations is discussed.

  13. EQUIVALENT MODELS IN COVARIANCE STRUCTURE-ANALYSIS

    NARCIS (Netherlands)

    LUIJBEN, TCW

    1991-01-01

    Defining equivalent models as those that reproduce the same set of covariance matrices, necessary and sufficient conditions are stated for the local equivalence of two expanded identified models M1 and M2 when fitting the more restricted model M0. Assuming several regularity conditions, the rank def

  14. Crecimiento pro pobre en Chile

    Directory of Open Access Journals (Sweden)

    Dante Contreras

    2008-01-01

    Full Text Available Con datos de panel para el periodo 1996-2001 y datos de corte transversal para 1990 y 2003, este artículo evalúa si el crecimiento en Chile ha sido “pro pobre”. Se emplean dos metodos: i se estima la “curva de incidencia del crecimiento” y luego se estima paramétrica y no paramétricamente la relación entre el ingreso per capita de los hogares en 1996 y el cambio en el ingreso de 1996-2001. Los resultados indican que el crecimiento ha incidido significativamente en la reducción de pobreza. Por otra parte, existe evidencia de convergencia para la mitad más pobre de la distribución de ingresos.

  15. Village microgrids: The Chile project

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, E.I.

    1997-12-01

    This paper describes a village application in Chile. The objective was to demonstrate the technical, economic and institutional viability of renewable energy for rural electrification, as well as to allow local partners to gain experience with hybrid/renewable technology, resource assessment, system siting and operation. A micro-grid system is viewed as a small village system, up to 1200 kWh/day load with a 50 kW peak load. It can consist of components of wind, photovoltaic, batteries, and conventional generators. It is usually associated with a single generator source, and uses batteries to cover light day time loads. This paper looks at the experiences learned from this project with regard to all of the facets of planning and installing this project.

  16. 2010 Chile Earthquake Aftershock Response

    Science.gov (United States)

    Barientos, Sergio

    2010-05-01

    The Mw=8.8 earthquake off the coast of Chile on 27 February 2010 is the 5th largest megathrust earthquake ever to be recorded and provides an unprecedented opportunity to advance our understanding of megathrust earthquakes and associated phenomena. The 2010 Chile earthquake ruptured the Concepcion-Constitucion segment of the Nazca/South America plate boundary, south of the Central Chile region and triggered a tsunami along the coast. Following the 2010 earthquake, a very energetic aftershock sequence is being observed in an area that is 600 km along strike from Valparaiso to 150 km south of Concepcion. Within the first three weeks there were over 260 aftershocks with magnitude 5.0 or greater and 18 with magnitude 6.0 or greater (NEIC, USGS). The Concepcion-Constitucion segment lies immediately north of the rupture zone associated with the great magnitude 9.5 Chile earthquake, and south of the 1906 and the 1985 Valparaiso earthquakes. The last great subduction earthquake in the region dates back to the February 1835 event described by Darwin (1871). Since 1835, part of the region was affected in the north by the Talca earthquake in December 1928, interpreted as a shallow dipping thrust event, and by the Chillan earthquake (Mw 7.9, January 1939), a slab-pull intermediate depth earthquake. For the last 30 years, geodetic studies in this area were consistent with a fully coupled elastic loading of the subduction interface at depth; this led to identify the area as a mature seismic gap with potential for an earthquake of magnitude of the order 8.5 or several earthquakes of lesser magnitude. What was less expected was the partial rupturing of the 1985 segment toward north. Today, the 2010 earthquake raises some disturbing questions: Why and how the rupture terminated where it did at the northern end? How did the 2010 earthquake load the adjacent segment to the north and did the 1985 earthquake only partially ruptured the plate interface leaving loaded asperities since

  17. Econometric analysis of realized covariation: high frequency based covariance, regression, and correlation in financial economics

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2004-01-01

    This paper analyses multivariate high frequency financial data using realized covariation. We provide a new asymptotic distribution theory for standard methods such as regression, correlation analysis, and covariance. It will be based on a fixed interval of time (e.g., a day or week), allowing...... the number of high frequency returns during this period to go to infinity. Our analysis allows us to study how high frequency correlations, regressions, and covariances change through time. In particular we provide confidence intervals for each of these quantities....

  18. Surface Observations from Punta Arenas, Chile

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface Observations from Punta Arenas, in extreme southern Chile. WMO station ID 85934. Period of record 1896-1954. The original forms were scanned at the Museo...

  19. 1960 Puerto Montt, Valdivia, Chile Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — On May 22, 1960, a Mw 9.5 earthquake, the largest earthquake ever instrumentally recorded, occurred in southern Chile. The series of earthquakes that followed...

  20. Unravelling Lorentz Covariance and the Spacetime Formalism

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2008-10-01

    Full Text Available We report the discovery of an exact mapping from Galilean time and space coordinates to Minkowski spacetime coordinates, showing that Lorentz covariance and the space-time construct are consistent with the existence of a dynamical 3-space, and absolute motion. We illustrate this mapping first with the standard theory of sound, as vibrations of a medium, which itself may be undergoing fluid motion, and which is covariant under Galilean coordinate transformations. By introducing a different non-physical class of space and time coordinates it may be cast into a form that is covariant under Lorentz transformations wherein the speed of sound is now the invariant speed. If this latter formalism were taken as fundamental and complete we would be lead to the introduction of a pseudo-Riemannian spacetime description of sound, with a metric characterised by an invariant speed of sound. This analysis is an allegory for the development of 20th century physics, but where the Lorentz covariant Maxwell equations were constructed first, and the Galilean form was later constructed by Hertz, but ignored. It is shown that the Lorentz covariance of the Maxwell equations only occurs because of the use of non-physical space and time coordinates. The use of this class of coordinates has confounded 20th century physics, and resulted in the existence of a allowing dynamical 3-space being overlooked. The discovery of the dynamics of this 3-space has lead to the derivation of an extended gravity theory as a quantum effect, and confirmed by numerous experiments and observations

  1. Unravelling Lorentz Covariance and the Spacetime Formalism

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2008-10-01

    Full Text Available We report the discovery of an exact mapping from Galilean time and space coordinates to Minkowski spacetime coordinates, showing that Lorentz covariance and the space- time construct are consistent with the existence of a dynamical 3-space, and “absolute motion”. We illustrate this mapping first with the standard theory of sound, as vibra- tions of a medium, which itself may be undergoing fluid motion, and which is covari- ant under Galilean coordinate transformations. By introducing a different non-physical class of space and time coordinates it may be cast into a form that is covariant under “Lorentz transformations” wherein the speed of sound is now the “invariant speed”. If this latter formalism were taken as fundamental and complete we would be lead to the introduction of a pseudo-Riemannian “spacetime” description of sound, with a metric characterised by an “invariant speed of sound”. This analysis is an allegory for the development of 20th century physics, but where the Lorentz covariant Maxwell equa- tions were constructed first, and the Galilean form was later constructed by Hertz, but ignored. It is shown that the Lorentz covariance of the Maxwell equations only occurs because of the use of non-physical space and time coordinates. The use of this class of coordinates has confounded 20th century physics, and resulted in the existence of a “flowing” dynamical 3-space being overlooked. The discovery of the dynamics of this 3-space has lead to the derivation of an extended gravity theory as a quantum effect, and confirmed by numerous experiments and observations

  2. Adjusting for covariate effects on classification accuracy using the covariate-adjusted receiver operating characteristic curve.

    Science.gov (United States)

    Janes, Holly; Pepe, Margaret S

    2009-06-01

    Recent scientific and technological innovations have produced an abundance of potential markers that are being investigated for their use in disease screening and diagnosis. In evaluating these markers, it is often necessary to account for covariates associated with the marker of interest. Covariates may include subject characteristics, expertise of the test operator, test procedures or aspects of specimen handling. In this paper, we propose the covariate-adjusted receiver operating characteristic curve, a measure of covariate-adjusted classification accuracy. Nonparametric and semiparametric estimators are proposed, asymptotic distribution theory is provided and finite sample performance is investigated. For illustration we characterize the age-adjusted discriminatory accuracy of prostate-specific antigen as a biomarker for prostate cancer.

  3. Stochastic Lipschitz continuity for high dimensional Lasso with multiple linear covariate structures or hidden linear covariates

    CERN Document Server

    Chi, Zhiyi

    2010-01-01

    Two extensions of generalized linear models are considered. In the first one, response variables depend on multiple linear combinations of covariates. In the second one, only response variables are observed while the linear covariates are missing. We derive stochastic Lipschitz continuity results for the loss functions involved in the regression problems and apply them to get bounds on estimation error for Lasso. Multivariate comparison results on Rademacher complexity are obtained as tools to establish the stochastic Lipschitz continuity results.

  4. Controlling the taxonomic variable: Taxonomic concept resolution for a southeastern United States herbarium portal

    Directory of Open Access Journals (Sweden)

    Nico Franz

    2016-09-01

    Full Text Available Overview. Taxonomic names are imperfect identifiers of specific and sometimes conflicting taxonomic perspectives in aggregated biodiversity data environments. The inherent ambiguities of names can be mitigated using syntactic and semantic conventions developed under the taxonomic concept approach. These include: (1 representation of taxonomic concept labels (TCLs: name sec. source to precisely identify name usages and meanings, (2 use of parent/child relationships to assemble separate taxonomic perspectives, and (3 expert provision of Region Connection Calculus articulations (RCC–5: congruence, [inverse] inclusion, overlap, exclusion that specify how data identified to different-sourced TCLs can be integrated. Application of these conventions greatly increases trust in biodiversity data networks, most of which promote unitary taxonomic 'syntheses' that obscure the actual diversity of expert-held views. Better design solutions allow users to control the taxonomic variable and thereby assess the robustness of their biological inferences under different perspectives. A unique constellation of prior efforts – including the powerful Symbiota collections software platform, the Euler/X multi-taxonomy alignment toolkit, and the "Weakley Flora" which entails 7,000 concepts and more than 75,000 RCC–5 articulations – provides the opportunity to build a first full-scale concept resolution service for SERNEC, the SouthEast Regional Network of Expertise and Collections, currently with 60 member herbaria and 2 million occurrence records. Intellectual merit. We have developed a multi-dimensional, step-wise plan to transition SERNEC's data culture from name- to concept-based practices. (1 We will engage SERNEC experts through annual, regional workshops and follow-up interactions that will foster buy-in and ultimately the completion of 12 community-identified use cases. (2. We will leverage RCC–5 data from the Weakley Flora and further development of

  5. Taxonomic status of Pelargonium reniforme Curt.

    Directory of Open Access Journals (Sweden)

    Janine E. Victor

    2014-07-01

    Full Text Available Background: Pelargonium reniforme Curt. is a morphologically variable species that many authors have attempted to split or combine. Confusion relating to the differences between the two subspecies currently included under P. reniforme has impeded attempts to assess their conservation status.  Pelargonium reniforme is closely related to  Pelargonium sidoides;  the two species are indistinguishable when not flowering and their distributions overlap in some areas.Objectives: With this study, we aimed to clarify the taxonomic status of the two subspecies of P. reniforme, which has relevance in terms of their conservation status.Method: Leaf shape, petiole length, internode length and flower colour were assessed by studying herbarium specimens of the two subspecies of  P. reniforme and specimens of P. sidoides. Living specimens of the two subspecies were also examined in their natural habitat.Results: The current investigation showed that the morphological characters used to distinguish the two subspecies of P. reniforme are too variable to separate them. Variation in some morphological characters may be related to environmental conditions.Conclusion: The recognition of the two subspecies of P. reniforme as distinct taxa is no longer justified.

  6. Karyomorphology of Taiwanese Begonia (Begoniaceae): taxonomic implications.

    Science.gov (United States)

    Oginuma, Kazuo; Peng, Ching-I

    2002-06-01

    The karyomorphology of all 14 species of Taiwanese Begonia was investigated to elucidate their chromosome features and chromosomal evolution. Among all species investigated, differences in chromosome features are found in: (1) chromosome number 2 n = 22, 26, 36, 38, 52, 60, 64, 82, and (2) frequencies of chromosomes with secondary, tertiary, and/or small constrictions of polyploids, ranging from 23% to 63%, which is higher than the expected value of about 9%. It is suggested that after polyploidization from the diploid species (i.e., 2 n = 22 and frequencies of chromosomes with secondary, tertiary, and/or small constrictions of polyploids of about 9%), chromosome translocations occurred, followed by a decrease in chromosome number, and subsequently stabilized genomes were formed in various species in Taiwan. The karyomorphological evidence also suggested that the chromosome morphology has evolved in parallel in the begonias belonging to different sections in Taiwan. The variation in chromosomal features is more complex than the variation in floral and fruit morphologies. Karyomorphological data also supports the recognition of five new species in Taiwan: Begonia bouffordii, B. chuyunshanensis, B. pinglinensis, B. tengchiana, and B. wutaiana. Based on detailed karyomorphological analyses, the taxonomic implications, speciation, and chromosomal evolution in Taiwanese Begoniaare discussed.

  7. Reference databases for taxonomic assignment in metagenomics.

    Science.gov (United States)

    Santamaria, Monica; Fosso, Bruno; Consiglio, Arianna; De Caro, Giorgio; Grillo, Giorgio; Licciulli, Flavio; Liuni, Sabino; Marzano, Marinella; Alonso-Alemany, Daniel; Valiente, Gabriel; Pesole, Graziano

    2012-11-01

    Metagenomics is providing an unprecedented access to the environmental microbial diversity. The amplicon-based metagenomics approach involves the PCR-targeted sequencing of a genetic locus fitting different features. Namely, it must be ubiquitous in the taxonomic range of interest, variable enough to discriminate between different species but flanked by highly conserved sequences, and of suitable size to be sequenced through next-generation platforms. The internal transcribed spacers 1 and 2 (ITS1 and ITS2) of the ribosomal DNA operon and one or more hyper-variable regions of 16S ribosomal RNA gene are typically used to identify fungal and bacterial species, respectively. In this context, reliable reference databases and taxonomies are crucial to assign amplicon sequence reads to the correct phylogenetic ranks. Several resources provide consistent phylogenetic classification of publicly available 16S ribosomal DNA sequences, whereas the state of ribosomal internal transcribed spacers reference databases is notably less advanced. In this review, we aim to give an overview of existing reference resources for both types of markers, highlighting strengths and possible shortcomings of their use for metagenomics purposes. Moreover, we present a new database, ITSoneDB, of well annotated and phylogenetically classified ITS1 sequences to be used as a reference collection in metagenomic studies of environmental fungal communities. ITSoneDB is available for download and browsing at http://itsonedb.ba.itb.cnr.it/.

  8. Taxonomic significance of trichomes micromorphology in cucurbits.

    Science.gov (United States)

    Ali, Mohammad Ajmal; Al-Hemaid, Fahad M A

    2011-01-01

    Studies on trichomes micromorphology using Scanning Electron Microscope (SEM) were undertaken in 23 species with one variety under 13 genera of the family Cucurbitaceae (viz., Benincasa hispida (Thunb.) Cogn., Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumis melo var. agrestis Naudin, Cucumis sativus L., Diplocyclos palmatus (L.) C. Jeffrey, Edgaria dargeelingensis C.B. Clarke, Gynostemma burmanicum King ex Chakr., Gynostemma pentaphyllum (Thunb.) Makino, Gynostemma pubescens (Gagnep.) C.Y. Wu, Hemsleya dipterygia Kuang & A.M. Lu, Lagenaria siceraria (Molina) Standl., Luffa acutangula (L.) Roxb., Luffa cylindrica M. Roem., Luffa echinata Roxb., Melothria heterophylla (Lour.) Cogn., Melothria leucocarpa (Blume) Cogn., Melothria maderspatana (L.) Cogn., Sechium edule (Jacq.) Sw., Thladiantha cordifolia (Blume) Cogn., Trichosanthes cucumerina L., T. cucumerina var. anguina (L.) Haines, Trichosanthes dioica Roxb., Trichosanthes lepiniana (Naudin) Cogn. and T. tricuspidata Lour.). The trichomes in the family Cucurbitaceae vary from unicellular to multicellular, conical to elongated, smooth to ridges, with or without flattened disk at base and cyctolithic appendages, thin to thick walled, curved at apices to blunt. Trichomes micromorphology in the family Cucurbitaceae was found significant taxonomically.

  9. Where Do Mexico and Chile Stand on Inclusive Education? Short Title: Inclusion in Mexico and Chile

    Science.gov (United States)

    García-Cedillo, Ismael; Romero-Contreras, Silvia; Ramos-Abadie, Liliana

    2015-01-01

    This paper discusses the background, current situation and challenges of educational integration and inclusive education in Mexico and Chile. These countries obtained similar low results on the academic achievement of their students (Mexico last and Chile second last) among OECD countries; and above average scores, among Latin-American countries.…

  10. Taxonomic indexing--extending the role of taxonomy.

    Science.gov (United States)

    Patterson, David J; Remsen, David; Marino, William A; Norton, Cathy

    2006-06-01

    Taxonomic indexing refers to a new array of taxonomically intelligent network services that use nomenclatural principles and elements of expert taxonomic knowledge to manage information about organisms. Taxonomic indexing was introduced to help manage the increasing amounts of digital information about biology. It has been designed to form a near basal layer in a layered cyberinfrastructure that deals with biological information. Taxonomic Indexing accommodates the special problems of using names of organisms to index biological material. It links alternative names for the same entity (reconciliation), and distinguishes between uses of the same name for different entities (disambiguation), and names are placed within an indefinite number of hierarchical schemes. In order to access all information on all organisms, Taxonomic indexing must be able to call on a registry of all names in all forms for all organisms. NameBank has been developed to meet that need. Taxonomic indexing is an area of informatics that overlaps with taxonomy, is dependent on the expert input of taxonomists, and reveals the relevance of the discipline to a wide audience.

  11. Healthcare Accessibility Shortfalls and Hospital Infrastructures in Chile

    Directory of Open Access Journals (Sweden)

    Stefano Mainardi

    2009-03-01

    Full Text Available To measure healthcare accessibility, a previous study formulated a stochastic cost frontier model, and applied it to distances of communal centres from nearest emergency hospitals in Chile. Based on a larger set of variables, this study re-estimates the distance threshold, and tests alternative specifications and distribution assumptions over the period 2000-05. Complementing the analysis, ordered probit regressions help examine the cross-commune allocation of hospitals with varying complexity of medical services. Thirdly, excess distance estimates are used with other covariates in tobit models of health sector infrastructure investments. Socio-economic, demographic and geophysical conditions, along with non-hospital healthcare facilities, explain spatial inequality of hospitals. Excess distances are robust to different model specifications and distribution assumptions, and do not appear to be compensated by standards of services of the nearest hospitals or new healthcare infrastructure and upgrading investments in support to the communes concerned. Communes with perceived inadequacy in timing of medical attention turn out to often register large location inefficiency too. For the most critical communal cases, the excess distance burden amounts.

  12. Covariant holography of a tachyonic accelerating universe

    Energy Technology Data Exchange (ETDEWEB)

    Rozas-Fernandez, Alberto [Consejo Superior de Investigaciones Cientificas, Instituto de Fisica Fundamental, Madrid (Spain); University of Portsmouth, Institute of Cosmology and Gravitation, Portsmouth (United Kingdom)

    2014-08-15

    We apply the holographic principle to a flat dark energy dominated Friedmann-Robertson-Walker spacetime filled with a tachyon scalar field with constant equation of state w = p/ρ, both for w > -1 and w < -1. By using a geometrical covariant procedure, which allows the construction of holographic hypersurfaces, we have obtained for each case the position of the preferred screen and have then compared these with those obtained by using the holographic dark energy model with the future event horizon as the infrared cutoff. In the phantom scenario, one of the two obtained holographic screens is placed on the big rip hypersurface, both for the covariant holographic formalism and the holographic phantom model. It is also analyzed whether the existence of these preferred screens allows a mathematically consistent formulation of fundamental theories based on the existence of an S-matrix at infinite distances. (orig.)

  13. Covariant holography of a tachyonic accelerating universe

    CERN Document Server

    Rozas-Fernández, Alberto

    2014-01-01

    We apply the holographic principle to a flat dark energy dominated Friedmann-Robertson-Walker spacetime filled with a tachyon scalar field with constant equation of state $w=p/\\rho$, both for $w>-1$ and $w<-1$. By using a geometrical covariant procedure, which allows the construction of holographic hypersurfaces, we have obtained for each case the position of the preferred screen and have then compared these with those obtained by using the holographic dark energy model with the future event horizon as the infrared cutoff. In the phantom scenario, one of the two obtained holographic screens is placed on the big rip hypersurface, both for the covariant holographic formalism and the holographic phantom model. It is also analysed whether the existence of these preferred screens allows a mathematically consistent formulation of fundamental theories based on the existence of a S matrix at infinite distances.

  14. Model selection for Poisson processes with covariates

    CERN Document Server

    Sart, Mathieu

    2011-01-01

    We observe $n$ inhomogeneous Poisson processes with covariates and aim at estimating their intensities. To handle this problem, we assume that the intensity of each Poisson process is of the form $s (\\cdot, x)$ where $x$ is the covariate and where $s$ is an unknown function. We propose a model selection approach where the models are used to approximate the multivariate function $s$. We show that our estimator satisfies an oracle-type inequality under very weak assumptions both on the intensities and the models. By using an Hellinger-type loss, we establish non-asymptotic risk bounds and specify them under various kind of assumptions on the target function $s$ such as being smooth or composite. Besides, we show that our estimation procedure is robust with respect to these assumptions.

  15. Errors on errors - Estimating cosmological parameter covariance

    CERN Document Server

    Joachimi, Benjamin

    2014-01-01

    Current and forthcoming cosmological data analyses share the challenge of huge datasets alongside increasingly tight requirements on the precision and accuracy of extracted cosmological parameters. The community is becoming increasingly aware that these requirements not only apply to the central values of parameters but, equally important, also to the error bars. Due to non-linear effects in the astrophysics, the instrument, and the analysis pipeline, data covariance matrices are usually not well known a priori and need to be estimated from the data itself, or from suites of large simulations. In either case, the finite number of realisations available to determine data covariances introduces significant biases and additional variance in the errors on cosmological parameters in a standard likelihood analysis. Here, we review recent work on quantifying these biases and additional variances and discuss approaches to remedy these effects.

  16. On covariance structure in noisy, big data

    Science.gov (United States)

    Paffenroth, Randy C.; Nong, Ryan; Du Toit, Philip C.

    2013-09-01

    Herein we describe theory and algorithms for detecting covariance structures in large, noisy data sets. Our work uses ideas from matrix completion and robust principal component analysis to detect the presence of low-rank covariance matrices, even when the data is noisy, distorted by large corruptions, and only partially observed. In fact, the ability to handle partial observations combined with ideas from randomized algorithms for matrix decomposition enables us to produce asymptotically fast algorithms. Herein we will provide numerical demonstrations of the methods and their convergence properties. While such methods have applicability to many problems, including mathematical finance, crime analysis, and other large-scale sensor fusion problems, our inspiration arises from applying these methods in the context of cyber network intrusion detection.

  17. Covariant Quantization of CPT-violating Photons

    CERN Document Server

    Colladay, D; Noordmans, J P; Potting, R

    2016-01-01

    We perform the covariant canonical quantization of the CPT- and Lorentz-symmetry-violating photon sector of the minimal Standard-Model Extension, which contains a general (timelike, lightlike, or spacelike) fixed background tensor $k_{AF}^\\mu$. Well-known stability issues, arising from complex-valued energy states, are solved by introducing a small photon mass, orders of magnitude below current experimental bounds. We explicitly construct a covariant basis of polarization vectors, in which the photon field can be expanded. We proceed to derive the Feynman propagator and show that the theory is microcausal. Despite the occurrence of negative energies and vacuum-Cherenkov radiation, we do not find any runaway stability issues, because the energy remains bounded from below. An important observation is that the ordering of the roots of the dispersion relations is the same in any observer frame, which allows for a frame-independent condition that selects the correct branch of the dispersion relation. This turns ou...

  18. Performance evaluation of sensor allocation algorithm based on covariance control

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The covariance control capability of sensor allocation algorithms based on covariance control strategy is an important index to evaluate the performance of these algorithms. Owing to lack of standard performance metric indices to evaluate covariance control capability, sensor allocation ratio, etc, there are no guides to follow in the design procedure of sensor allocation algorithm in practical applications. To meet these demands, three quantified performance metric indices are presented, which are average covariance misadjustment quantity (ACMQ), average sensor allocation ratio (ASAR) and matrix metric influence factor (MMIF), where ACMQ, ASAR and MMIF quantify the covariance control capability, the usage of sensor resources and the robustness of sensor allocation algorithm, respectively. Meanwhile, a covariance adaptive sensor allocation algorithm based on a new objective function is proposed to improve the covariance control capability of the algorithm based on information gain. The experiment results show that the proposed algorithm have the advantage over the preceding sensor allocation algorithm in covariance control capability and robustness.

  19. Symmetry and Covariance of Non-relativistic Quantum Mechanics

    OpenAIRE

    Omote, Minoru; kamefuchi, Susumu

    2000-01-01

    On the basis of a 5-dimensional form of space-time transformations non-relativistic quantum mechanics is reformulated in a manifestly covariant manner. The resulting covariance resembles that of the conventional relativistic quantum mechanics.

  20. Covariant quantization of the CBS superparticle

    Science.gov (United States)

    Grassi, P. A.; Policastro, G.; Porrati, M.

    2001-07-01

    The quantization of the Casalbuoni-Brink-Schwarz superparticle is performed in an explicitly covariant way using the antibracket formalism. Since an infinite number of ghost fields are required, within a suitable off-shell twistor-like formalism, we are able to fix the gauge of each ghost sector without modifying the physical content of the theory. The computation reveals that the antibracket cohomology contains only the physical degrees of freedom.

  1. Unbiased risk estimation method for covariance estimation

    CERN Document Server

    Lescornel, Hélène; Chabriac, Claudie

    2011-01-01

    We consider a model selection estimator of the covariance of a random process. Using the Unbiased Risk Estimation (URE) method, we build an estimator of the risk which allows to select an estimator in a collection of model. Then, we present an oracle inequality which ensures that the risk of the selected estimator is close to the risk of the oracle. Simulations show the efficiency of this methodology.

  2. Linear Covariance Analysis for a Lunar Lander

    Science.gov (United States)

    Jang, Jiann-Woei; Bhatt, Sagar; Fritz, Matthew; Woffinden, David; May, Darryl; Braden, Ellen; Hannan, Michael

    2017-01-01

    A next-generation lunar lander Guidance, Navigation, and Control (GNC) system, which includes a state-of-the-art optical sensor suite, is proposed in a concept design cycle. The design goal is to allow the lander to softly land within the prescribed landing precision. The achievement of this precision landing requirement depends on proper selection of the sensor suite. In this paper, a robust sensor selection procedure is demonstrated using a Linear Covariance (LinCov) analysis tool developed by Draper.

  3. Risk evaluation with enhaced covariance matrix

    CERN Document Server

    Urbanowicz, K; Richmond, P; Holyst, Janusz A.; Richmond, Peter; Urbanowicz, Krzysztof

    2006-01-01

    We propose a route for the evaluation of risk based on a transformation of the covariance matrix. The approach uses a `potential' or `objective' function. This allows us to rescale data from diferent assets (or sources) such that each set then has similar statistical properties in terms of their probability distributions. The method is tested using historical data from both the New York and Warsaw Stock Exchanges.

  4. Torsion and geometrostasis in covariant superstrings

    Energy Technology Data Exchange (ETDEWEB)

    Zachos, C.

    1985-01-01

    The covariant action for freely propagating heterotic superstrings consists of a metric and a torsion term with a special relative strength. It is shown that the strength for which torsion flattens the underlying 10-dimensional superspace geometry is precisely that which yields free oscillators on the light cone. This is in complete analogy with the geometrostasis of two-dimensional sigma-models with Wess-Zumino interactions. 13 refs.

  5. Twisted Covariant Noncommutative Self-dual Gravity

    CERN Document Server

    Estrada-Jimenez, S; Obregón, O; Ramírez, C

    2008-01-01

    A twisted covariant formulation of noncommutative self-dual gravity is presented. The recent formulation introduced by J. Wess and coworkers for constructing twisted Yang-Mills fields is used. It is shown that the noncommutative torsion is solved at any order of the $\\theta$-expansion in terms of the tetrad and the extra fields of the theory. In the process the first order expansion in $\\theta$ for the Pleba\\'nski action is explicitly obtained.

  6. Economical phase-covariant cloning with multiclones

    Institute of Scientific and Technical Information of China (English)

    Zhang Wen-Hai; Ye Liu

    2009-01-01

    This paper presents a very simple method to derive the explicit transformations of the optimal economical to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D'Ariano G M and Macchiavello C 2003 Phys. Rcv. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y,Lamata L et al,2007 Phys. Rev. Lett. 98 150502] in which M must be odd.

  7. Adaptive Covariance Estimation with model selection

    CERN Document Server

    Biscay, Rolando; Loubes, Jean-Michel

    2012-01-01

    We provide in this paper a fully adaptive penalized procedure to select a covariance among a collection of models observing i.i.d replications of the process at fixed observation points. For this we generalize previous results of Bigot and al. and propose to use a data driven penalty to obtain an oracle inequality for the estimator. We prove that this method is an extension to the matricial regression model of the work by Baraud.

  8. Superfield quantization in Sp(2) covariant formalism

    CERN Document Server

    Lavrov, P M

    2001-01-01

    The rules of the superfield Sp(2) covariant quantization of the arbitrary gauge theories for the case of the introduction of the gauging with the derivative equations for the gauge functional are generalized. The possibilities of realization of the expanded anti-brackets are considered and it is shown, that only one of the realizations is compatible with the transformations of the expanded BRST-symmetry in the form of super translations along the Grassmann superspace coordinates

  9. Covariant Calculus for Effective String Theories

    OpenAIRE

    Dass, N. D. Hari; Matlock, Peter

    2007-01-01

    A covariant calculus for the construction of effective string theories is developed. Effective string theory, describing quantum string-like excitations in arbitrary dimension, has in the past been constructed using the principles of conformal field theory, but not in a systematic way. Using the freedom of choice of field definition, a particular field definition is made in a systematic way to allow an explicit construction of effective string theories with manifest exact conformal symmetry. ...

  10. [Papillomavirus and cervical cancer in Chile].

    Science.gov (United States)

    O'Ryan, Miguel; Valenzuela, María Teresa

    2008-11-01

    Molecular, clinical and epidemiological studies have established beyond doubt that human papiloma viruses (HPV) cause cervical cancer. The virus is also associated with genital warts and other less common cancers in oropharynx, vulva, vagina and penis. Worldwide, VPH genotypes 16 and 18 are the most common high risk genotypes, detected in near 70% of women with cervical cancer. The discovery of a cause-effect relationship between several carcinogenic microorganisms and cancer open avenues for new diagnostic, treatment and prevention strategies. In this issue of Revista Médica de Chile, two papers on HPV are presented. Guzman and colleagues demonstrate that HPV can be detected in 66% to 77% of healthy male adolescents bypolymerase chain reaction and that positivity depends on the site of the penis that is sampled. These results support the role of male to female transmission of high risk HPVs in Chile and should lead to even more active educational campaigns. The second paper provides recommendations for HPV vaccine use in Chile, generated by the Immunization Advisory Committee of the Chilean Infectious Disease Society. To issue these recommendations, the Committee analyzes the epidemiological information available on HPV infection and cervical cancer in Chile, vaccine safety and effectiveness data, and describes cost-effectiveness studies. Taking into account that universal vaccination is controversial, the Committee favors vaccine use in Chile and it's incorporation into a national program. However, there is an indication that the country requires the implementation of an integrated surveillance approach including cross matching of data obtained from HPV genotype surveillance, monitoring of vaccination coverage, and surveillance of cervical cancer. The final decision of universal vaccine use in Chile should be based on a through analysis of information.ev Mid Chile

  11. How covariant is the galaxy luminosity function?

    CERN Document Server

    Smith, Robert E

    2012-01-01

    We investigate the error properties of certain galaxy luminosity function (GLF) estimators. Using a cluster expansion of the density field, we show how, for both volume and flux limited samples, the GLF estimates are covariant. The covariance matrix can be decomposed into three pieces: a diagonal term arising from Poisson noise; a sample variance term arising from large-scale structure in the survey volume; an occupancy covariance term arising due to galaxies of different luminosities inhabiting the same cluster. To evaluate the theory one needs: the mass function and bias of clusters, and the conditional luminosity function (CLF). We use a semi-analytic model (SAM) galaxy catalogue from the Millennium run N-body simulation and the CLF of Yang et al. (2003) to explore these effects. The GLF estimates from the SAM and the CLF qualitatively reproduce results from the 2dFGRS. We also measure the luminosity dependence of clustering in the SAM and find reasonable agreement with 2dFGRS results for bright galaxies. ...

  12. Development of covariance capabilities in EMPIRE code

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.; Pigni, M.T.; Oblozinsky, P.; Mughabghab, S.F.; Mattoon, C.M.; Capote, R.; Cho, Young-Sik; Trkov, A.

    2008-06-24

    The nuclear reaction code EMPIRE has been extended to provide evaluation capabilities for neutron cross section covariances in the thermal, resolved resonance, unresolved resonance and fast neutron regions. The Atlas of Neutron Resonances by Mughabghab is used as a primary source of information on uncertainties at low energies. Care is taken to ensure consistency among the resonance parameter uncertainties and those for thermal cross sections. The resulting resonance parameter covariances are formatted in the ENDF-6 File 32. In the fast neutron range our methodology is based on model calculations with the code EMPIRE combined with experimental data through several available approaches. The model-based covariances can be obtained using deterministic (Kalman) or stochastic (Monte Carlo) propagation of model parameter uncertainties. We show that these two procedures yield comparable results. The Kalman filter and/or the generalized least square fitting procedures are employed to incorporate experimental information. We compare the two approaches analyzing results for the major reaction channels on {sup 89}Y. We also discuss a long-standing issue of unreasonably low uncertainties and link it to the rigidity of the model.

  13. High-dimensional covariance estimation with high-dimensional data

    CERN Document Server

    Pourahmadi, Mohsen

    2013-01-01

    Methods for estimating sparse and large covariance matrices Covariance and correlation matrices play fundamental roles in every aspect of the analysis of multivariate data collected from a variety of fields including business and economics, health care, engineering, and environmental and physical sciences. High-Dimensional Covariance Estimation provides accessible and comprehensive coverage of the classical and modern approaches for estimating covariance matrices as well as their applications to the rapidly developing areas lying at the intersection of statistics and mac

  14. Genome-based Taxonomic Classification of Bacteroidetes

    Directory of Open Access Journals (Sweden)

    Richard L. Hahnke

    2016-12-01

    Full Text Available The bacterial phylum Bacteroidetes, characterized by a distinct gliding motility, occurs in a broad variety of ecosystems, habitats, life styles and physiologies. Accordingly, taxonomic classification of the phylum, based on a limited number of features, proved difficult and controversial in the past, for example, when decisions were based on unresolved phylogenetic trees of the 16S rRNA gene sequence. Here we use a large collection of type-strain genomes from Bacteroidetes and closely related phyla for assessing their taxonomy based on the principles of phylogenetic classification and trees inferred from genome-scale data. No significant conflict between 16S rRNA gene and whole-genome phylogenetic analysis is found, whereas many but not all of the involved taxa are supported as monophyletic groups, particularly in the genome-scale trees. Phenotypic and phylogenomic features support the separation of Balneolaceae as new phylum Balneolaeota from Rhodothermaeota and of Saprospiraceae as new class Saprospiria from Chitinophagia. Epilithonimonas is nested within the older genus Chryseobacterium and without significant phenotypic differences; thus merging the two genera is proposed. Similarly, Vitellibacter is proposed to be included in Aequorivita. Flexibacter is confirmed as being heterogeneous and dissected, yielding six distinct genera. Hallella seregens is a later heterotypic synonym of Prevotella dentalis. Compared to values directly calculated from genome sequences, the G+C content mentioned in many species descriptions is too imprecise; moreover, corrected G+C content values have a significantly better fit to the phylogeny. Corresponding emendations of species descriptions are provided where necessary. Whereas most observed conflict with the current classification of Bacteroidetes is already visible in 16S rRNA gene trees, as expected whole-genome phylogenies are much better resolved.

  15. Genome-Based Taxonomic Classification of Bacteroidetes.

    Science.gov (United States)

    Hahnke, Richard L; Meier-Kolthoff, Jan P; García-López, Marina; Mukherjee, Supratim; Huntemann, Marcel; Ivanova, Natalia N; Woyke, Tanja; Kyrpides, Nikos C; Klenk, Hans-Peter; Göker, Markus

    2016-01-01

    The bacterial phylum Bacteroidetes, characterized by a distinct gliding motility, occurs in a broad variety of ecosystems, habitats, life styles, and physiologies. Accordingly, taxonomic classification of the phylum, based on a limited number of features, proved difficult and controversial in the past, for example, when decisions were based on unresolved phylogenetic trees of the 16S rRNA gene sequence. Here we use a large collection of type-strain genomes from Bacteroidetes and closely related phyla for assessing their taxonomy based on the principles of phylogenetic classification and trees inferred from genome-scale data. No significant conflict between 16S rRNA gene and whole-genome phylogenetic analysis is found, whereas many but not all of the involved taxa are supported as monophyletic groups, particularly in the genome-scale trees. Phenotypic and phylogenomic features support the separation of Balneolaceae as new phylum Balneolaeota from Rhodothermaeota and of Saprospiraceae as new class Saprospiria from Chitinophagia. Epilithonimonas is nested within the older genus Chryseobacterium and without significant phenotypic differences; thus merging the two genera is proposed. Similarly, Vitellibacter is proposed to be included in Aequorivita. Flexibacter is confirmed as being heterogeneous and dissected, yielding six distinct genera. Hallella seregens is a later heterotypic synonym of Prevotella dentalis. Compared to values directly calculated from genome sequences, the G+C content mentioned in many species descriptions is too imprecise; moreover, corrected G+C content values have a significantly better fit to the phylogeny. Corresponding emendations of species descriptions are provided where necessary. Whereas most observed conflict with the current classification of Bacteroidetes is already visible in 16S rRNA gene trees, as expected whole-genome phylogenies are much better resolved.

  16. Earth Observation System Flight Dynamics System Covariance Realism

    Science.gov (United States)

    Zaidi, Waqar H.; Tracewell, David

    2016-01-01

    This presentation applies a covariance realism technique to the National Aeronautics and Space Administration (NASA) Earth Observation System (EOS) Aqua and Aura spacecraft based on inferential statistics. The technique consists of three parts: collection calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics.

  17. Helicobacter pylori infection in Chile.

    Science.gov (United States)

    Figueroa, G; Acuña, R; Troncoso, M; Portell, D P; Toledo, M S; Valenzuela, J

    1997-11-01

    This article summarizes studies designed to evaluate the role of Helicobacter pylori infection in Chile, described in 21 reports from nine centers in various Chilean regions published between 1985 and 1995. According to their data, H. pylori infection is quite frequent among patients with a variety of gastric conditions, including adults (43%-92%) and children (6%-100%). Levels of specific IgG antibodies to H. pylori are also elevated among patients with duodenal ulcers (100%) and gastritis (86%) as well as asymptomatic adults (75%). Combination therapy with three (but not two) drugs has been proved effective, with clinical improvement, ulcer cure, and H. pylori eradication occurring in well-controlled studies. Available evidence suggests that antibiotic resistance is not a major problem in treatment. The H. pylori reinfection rate is low (4.2% per year), suggesting that combination therapy with three drugs constitutes a cost-effective alternative for treating colonized symptomatic patients. Concurrent preliminary studies revealed that antibodies to VacA but not CagA proteins correlate with disease severity in Chilean patients. It can be concluded that local research assists local administrators of health resources to implement adequate policies to prevent, control, and treat H. pylori-related pathologies.

  18. Regulated electricity retailing in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Galetovic, Alexander, E-mail: alexander@galetovic.cl [Facultad de Ciencias Economicas y Empresariales, Universidad de los Andes, Santiago, Chile. Av. San Carlos de Apoquindo 2200, Las Condes, Santiago (Chile); Munoz, Cristian M., E-mail: cmunozm@aes.com [AES Gener and Departamento de Ingenieria Electrica, Universidad Catolica de Chile (Chile)

    2011-10-15

    While some countries have unbundled distribution and retailing, skeptics argue that the physical attributes of electricity make retailers redundant. Instead, it is claimed that passive pass through of wholesale prices plus regulated charges for transmission and distribution suffice for customers to benefit from competitive generation markets. We review the Chilean experience with regulated retailing and pass through of wholesale prices. We argue that when energy wholesale prices are volatile and prices are stabilized, distortions emerge. Regulated retailers gain little by mitigating or correcting them. On the contrary, sometimes price distortions increase their profits. We estimate the cost of three distortions that neither regulated retailers nor the regulator have shown any interest in correcting. - Highlights: > We review Chile's experience with regulated electricity retailing. > Distortions emerge when energy wholesale prices are volatile and prices stabilized. > Regulated retailers gain little by mitigating or correcting distortions. > Sometimes price distortions increase retailers' profits. > We estimate the cost of three distortions, which retailers have not corrected.

  19. The Revolutionary Left and Terrorist Violence in Chile.

    Science.gov (United States)

    1986-06-01

    Fraude Electoral Designada por la Facultad de Derecho de la Pontifica Universidad de Chile," in Libro Blanco del Cambio de Gobierno de Chile, Editorial...armed forces. Argentine police arrested Edgardo Enriquez, whom they deported to Chile. Humberto Sotomayor apparently left the movement, leaving Andres...often either deport them or sentence them to jail or internal -14- exile. The government seems able to capture the miristas who infiltrate into Chile

  20. [Beginning of the Microbiology education in Chile: formation centers].

    Science.gov (United States)

    Osorio, Carlos

    2015-08-01

    The first Chair of Microbiology in Chile was created in the School of Medicine of the Cañadilla at the University of Chile in 1892. Dr. Alejandro del Río Soto Aguilar was its first Professor. For almost three decades it was the only educational center for microbiologists in Chile. Among them were the first Professors of the new School of Medicine of the Catholic University of Chile and of the University of Concepción.

  1. Covariant Quantum Gravity with Continuous Quantum Geometry I: Covariant Hamiltonian Framework

    CERN Document Server

    Pilc, Marián

    2016-01-01

    The first part of the series is devoted to the formulation of the Einstein-Cartan Theory within the covariant hamiltonian framework. In the first section the general multisymplectic approach is revised and the notion of the d-jet bundles is introduced. Since the whole Standard Model Lagrangian (including gravity) can be written as the functional of the forms, the structure of the d-jet bundles is more appropriate for the covariant hamiltonian analysis than the standard jet bundle approach. The definition of the local covariant Poisson bracket on the space of covariant observables is recalled. The main goal of the work is to show that the gauge group of the Einstein-Cartan theory is given by the semidirect product of the local Lorentz group and the group of spacetime diffeomorphisms. Vanishing of the integral generators of the gauge group is equivalent to equations of motion of the Einstein-Cartan theory and the local covariant algebra generated by Noether's currents is closed Lie algebra.

  2. Los patelogastrópodos intermareales de Chile y Perú Intertidal limpets of Chile and Peru

    Directory of Open Access Journals (Sweden)

    CARMEN ESPOZ

    2004-06-01

    diversos del mundo. Más aún, esta variabilidad y flexibilidad pueden ser responsables de las confusiones taxonómicas que han rodeado a este conjunto faunísticoIn this study we present a classification system reflecting the phylogenetic relationships for the intertidal patellogastropods of Chile and Peru. We infer phylogenetic relationships between limpets species using DNA sequences from the 16S region of the mitochondrial genome. We include a comparative limpet study of: shell structure, color and morphological patterns of the shell, radular teeth and anatomy. Additionally, we provide information about the distribution and ecology for members of this group within the studied area. The results show a Chilean-Peruvian Lottiidae fauna consisting of at least nine species, which are grouped into a single monophyletic clade Scurria (S. variabilis, S. zebrina, S. viridula, S. plana, S. scurra, S. araucana, S. ceciliana and a non identificated species, and a "problematic taxon" preliminarily assigned to the genus Lottia (Lottia orbignyi. The group of species is present in the intertidal rocky shores between 5º S and 54º S, from the upper to the lower intertidal fringes, ranging from exposed to protected areas. The systematic outcome of this study suggests the synonymization of S. parasitica to S. variabilis, and of S. ceciliana to S. boehmita. According to our field results, the species S. variabilis shows at least three ecophenotypes: (1 on rocky substrates along the full geographic range, (2 on the shells of the key-hole limpets: Fissurella crassa and F. limbata mainly in central and south of Chile, and (3 on the chiton plates of Enoplochiton niger in the north of Chile and south of Perú. S. ceciliana is a species in which morphology and color patterns are highly variable. In general, this variability indicates that the Chilean-Peruvian limpet species are among the most complex and diverse limpet fauna in the world. This, may reflects the taxonomic confusion which has

  3. Developing green supply chain management strategies: A taxonomic approach

    OpenAIRE

    Michael Mutingi

    2013-01-01

    Purpose: The objective of this research is to explore the empirical green supply chain activities found in literature, and to develop a taxonomic framework that can be used for formulating appropriate strategies for green supply chains, based on characteristic dimensions for the green supply chain. Design/methodology/approach: The taxonomic framework is developed through (i) analysis of green supply chain activities found in existing empirical work or case studies recorded in literature, (ii)...

  4. 7 CFR 319.56-38 - Citrus from Chile.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Citrus from Chile. 319.56-38 Section 319.56-38... from Chile. Clementines (Citrus reticulata Blanco var. Clementine), mandarins (Citrus reticulata Blanco), and tangerines (Citrus reticulata Blanco) may be imported into the United States from Chile,...

  5. Taxonomic diversity and distinctness indices in assessment of weed communities

    Directory of Open Access Journals (Sweden)

    Magdalena Jastrzębska

    2012-12-01

    Full Text Available This paper contains an analysis of taxonomic weed biodiversity in the cultivation of spring barley in the period of 1990-2004, grown in crop rotation after potato with a 25% share of this cereal (potato - spring barley - field pea - winter triticale as well as in crop rotation with its 75% share (potato - spring barley - spring barley - spring barley in which barley was grown once and twice after the same barley crop. No weed control was used in the present experiment. Every year in the spring (at full emergence of the cereal crop and before harvest, the species composition and the numbers of individual weed species were determined, as well as weed biomass before harvest. On this basis, the taxonomic diversity and distinctness indices were calculated. Potato/barley crop rotation with a 25% share of this cereal and growing spring barley once and twice after the same barley crop did not differentiate taxonomic weed biodiversity. However, it was positively correlated with rainfall abundance during the growing season and negatively correlated with mean temperature. The taxonomic diversity indices were positively correlated with species richness and species diversity, whereas the taxonomic distinctness indices did not generally show any relationship with these measures. Spring barley grain yield did not depend on taxonomic biodiversity of weed communities.

  6. Expedition Atacama - project AMOS in Chile

    Science.gov (United States)

    Tóth, J.; Kaniansky, S.

    2016-01-01

    The Slovak Video Meteor Network operates since 2009 (Tóth et al., 2011). It currently consists of four semi-automated all-sky video cameras, developed at the Astronomical Observatory in Modra, Comenius University in Bratislava, Slovakia. Two new generations of AMOS (All-sky Meteor Orbit System) cameras operate fully automatically at the Canary Islands, Tenerife and La Palma, since March 2015 (Tóth et al., 2015). As a logical step, we plan to cover the southern hemisphere from Chile. We present observational experiences in meteor astronomy from the Atacama Desert and other astronomical sites in Chile. This summary of the observations lists meteor spectra records (26) between Nov.5-13, 2015 mostly Taurid meteors, single and double station meteors as well as the first light from the permanent AMOS stations in Chile.

  7. Distribution and habitat ecology of the sorediate species of Menegazzia (Parmeliaceae, lichenized Ascomycota in Chile Distribución y ecología de las especies sorediosas de Menegazzia (Parmeliaceae, Ascomycota liquenizado en Chile

    Directory of Open Access Journals (Sweden)

    JARLE W BJERKE

    2003-03-01

    Full Text Available ABSTRACT The taxonomy and ecology of the sorediate species of Menegazzia from the southernmost regions of Chile and Argentina and the South Atlantic Islands was recently published, only with sporadic reports from the more northern regions. In the present work the distribution patterns and habitat ecology of the sorediate species are discussed, with emphasis on the area north of 48º S. Eleven species are treated. Menegazzia subpertusa, an epiphyte of sclerophyll scrubs, is recorded from South America for the first time (Chile and Argentina. Menegazzia neozelandica has a disjunct distribution in Chile, with occurrences in Fray Jorge (Fourth Region of Chile and on Islas Juan Fernández, and along the coast south of latitude 38º S. Menegazzia kawesqarica and M. tenuis are most common in the southernmost part of Chile, but are also found at high altitudes at lower latitudes. Additional treated species are M. chrysogaster, M. fumarprotocetrarica, M. globulifera, M. magellanica, M. norsorediata, M. sanguinascens and M. wandae. Several of the sorediate species are early colonisers of newly developed substrates. They show variable occurrences along light and humidity gradients. Distribution maps and a revised key are presented.Recientemente se han publicado datos sobre la taxonomía y ecología de las especies sorediosas de Menegazzia representadas en las regiones más australes de Chile y Argentina e islas del Atlántico Sur, además de registros esporádicos en zonas ubicadas más al norte en Chile. En este trabajo se discuten los patrones de distribución y la ecología del hábitat de 11 especies sorediosas, con especial enfásis en aquellas que se desarrollan al norte de los 48º S. Menegazzia subpertusa, un epífito de arbustos esclerófilos, se registra por primera vez en América (Chile y Argentina. Menegazzia neozelandica tiene una distribución discontinua en Chile; ha sido recolectada en Fray Jorge (Cuarta Región de Chile, Islas Juan Fern

  8. Ecología y biodiversidad de vertebrados de Chile: Análisis comentado de la Zoología de Claude Gay Ecology and biodiversity of vertebrates in Chile: A commented analysis of the Zoology of Claude Gay

    Directory of Open Access Journals (Sweden)

    FABIAN M JAKSIC

    2010-01-01

    Full Text Available A partir de la revisión de la sección zoológica de la Historia Física y Política de Chile elaborada por Claude Gay, analizamos su contribución al conocimiento de los vertebrados chilenos. Esta sección incluyó la descripción de 483 especies distribuidas en 68 mamíferos, 259 aves, 31 reptiles, 16 anfibios y 109 peces; de ellas, 50 especies fueron descritas por primera vez para la ciencia, pero los análisis taxonómicos posteriores sinonimizaron cerca del 58 % de ellas, quedando como válidas solo 21 especies. Este valor implica que el 1.1 % de la fauna de vertebrados de Chile actualmente conocida (unas 1900 especies fue descrita por primera vez en dicha obra monumental.By reviewing the zoological section of the Historia Física y Política de Chile written by Claude Gay, we analyze his contributions to the understanding of the Chilean vertebrates, which included 483 species: 68 mammals, 259 birds, 31 reptiles, 16 amphibians, and 109 fishes. Gay documented 50 species as new taxa to science, but subsequent taxonomic analyses sinonimized 58 % of those species; thus currently only 21 species are recognized as valid. This means that 1.1 % of the Chilean vertebrates currently recognized were described in this monumental publication.

  9. DETERMINANTES DE LA LECTURA EN CHILE

    OpenAIRE

    2007-01-01

    Los lectores se forman principalmente leyendo libros. Numerosa evidencia muestra que en Chile los niveles de lectura son bajos, tanto en términos cuantitativos como cualitativos. Existe, además, un consenso respecto de la importancia de la habilidad y el hábito de lectura tanto para el individuo como para la sociedad y la economía. El presente trabajo tiene como objetivo analizar los factores que afectan el nivel de lectura de libros en Chile. Para ello, se revisa el rol que desempeña la l...

  10. Gallilei covariant quantum mechanics in electromagnetic fields

    Directory of Open Access Journals (Sweden)

    H. E. Wilhelm

    1985-01-01

    Full Text Available A formulation of the quantum mechanics of charged particles in time-dependent electromagnetic fields is presented, in which both the Schroedinger equation and wave equations for the electromagnetic potentials are Galilei covariant, it is shown that the Galilean relativity principle leads to the introduction of the electromagnetic substratum in which the matter and electromagnetic waves propagate. The electromagnetic substratum effects are quantitatively significant for quantum mechanics in reference frames, in which the substratum velocity w is in magnitude comparable with the velocity of light c. The electromagnetic substratum velocity w occurs explicitly in the wave equations for the electromagnetic potentials but not in the Schroedinger equation.

  11. Covariant harmonic oscillators and coupled harmonic oscillators

    Science.gov (United States)

    Han, Daesoo; Kim, Young S.; Noz, Marilyn E.

    1995-01-01

    It is shown that the system of two coupled harmonic oscillators shares the basic symmetry properties with the covariant harmonic oscillator formalism which provides a concise description of the basic features of relativistic hadronic features observed in high-energy laboratories. It is shown also that the coupled oscillator system has the SL(4,r) symmetry in classical mechanics, while the present formulation of quantum mechanics can accommodate only the Sp(4,r) portion of the SL(4,r) symmetry. The possible role of the SL(4,r) symmetry in quantum mechanics is discussed.

  12. Minimal covariant observables identifying all pure states

    Energy Technology Data Exchange (ETDEWEB)

    Carmeli, Claudio, E-mail: claudio.carmeli@gmail.com [D.I.M.E., Università di Genova, Via Cadorna 2, I-17100 Savona (Italy); I.N.F.N., Sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku (Finland); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); I.N.F.N., Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy)

    2013-09-02

    It has been recently shown by Heinosaari, Mazzarella and Wolf (2013) [1] that an observable that identifies all pure states of a d-dimensional quantum system has minimally 4d−4 outcomes or slightly less (the exact number depending on d). However, no simple construction of this type of minimal observable is known. We investigate covariant observables that identify all pure states and have minimal number of outcomes. It is shown that the existence of this kind of observables depends on the dimension of the Hilbert space.

  13. Spatiotemporal noise covariance estimation from limited empirical magnetoencephalographic data

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Sung C [MS-D454, Applied Modern Physics Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Plis, Sergey M [MS-D454, Applied Modern Physics Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Ranken, Doug M [MS-D454, Applied Modern Physics Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Schmidt, David M [MS-D454, Applied Modern Physics Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2006-11-07

    The performance of parametric magnetoencephalography (MEG) and electroencephalography (EEG) source localization approaches can be degraded by the use of poor background noise covariance estimates. In general, estimation of the noise covariance for spatiotemporal analysis is difficult mainly due to the limited noise information available. Furthermore, its estimation requires a large amount of storage and a one-time but very large (and sometimes intractable) calculation or its inverse. To overcome these difficulties, noise covariance models consisting of one pair or a sum of multi-pairs of Kronecker products of spatial covariance and temporal covariance have been proposed. However, these approaches cannot be applied when the noise information is very limited, i.e., the amount of noise information is less than the degrees of freedom of the noise covariance models. A common example of this is when only averaged noise data are available for a limited prestimulus region (typically at most a few hundred milliseconds duration). For such cases, a diagonal spatiotemporal noise covariance model consisting of sensor variances with no spatial or temporal correlation has been the common choice for spatiotemporal analysis. In this work, we propose a different noise covariance model which consists of diagonal spatial noise covariance and Toeplitz temporal noise covariance. It can easily be estimated from limited noise information, and no time-consuming optimization and data-processing are required. Thus, it can be used as an alternative choice when one-pair or multi-pair noise covariance models cannot be estimated due to lack of noise information. To verify its capability we used Bayesian inference dipole analysis and a number of simulated and empirical datasets. We compared this covariance model with other existing covariance models such as conventional diagonal covariance, one-pair and multi-pair noise covariance models, when noise information is sufficient to estimate them. We

  14. Covariant Entropy Bound and Padmanabhan's Emergent Paradigm

    CERN Document Server

    Hadi, H; Darabi, F

    2016-01-01

    The covariant entropy conjecture is invariant under time reversal and consequently its origin must be statistical rather than thermodynamical. This may impose a fundamental constraint on the number of degrees of freedom in nature. Indeed, the covariant entropy bound imposes an upper entropy bound for any physical system. Considering a cosmological system, we show that Padmanabhan's emergent paradigm, which indicates that the emergence of cosmic space is due to the discrepancy between the surface and bulk degrees of freedom, leads to a lower entropy bound. The lower and upper entropy bounds may coincide on the apparent horizon for the radiation field and dark energy with the equations of state $\\omega=\\frac{1}{3}$ and $\\omega=-1$, respectively. Moreover, the maximal entropy inside the apparent horizon occurs when it is filled completely by the radiation field or dark energy. It turns out that for dark energy case (pure de Sitter space)\\ the holographic principle is satisfied in the sense that the number of deg...

  15. Estimating the power spectrum covariance matrix with fewer mock samples

    CERN Document Server

    Pearson, David W

    2015-01-01

    The covariance matrices of power-spectrum (P(k)) measurements from galaxy surveys are difficult to compute theoretically. The current best practice is to estimate covariance matrices by computing a sample covariance of a large number of mock catalogues. The next generation of galaxy surveys will require thousands of large volume mocks to determine the covariance matrices to desired accuracy. The errors in the inverse covariance matrix are larger and scale with the number of P(k) bins, making the problem even more acute. We develop a method of estimating covariance matrices using a theoretically justified, few-parameter model, calibrated with mock catalogues. Using a set of 600 BOSS DR11 mock catalogues, we show that a seven parameter model is sufficient to fit the covariance matrix of BOSS DR11 P(k) measurements. The covariance computed with this method is better than the sample covariance at any number of mocks and only ~100 mocks are required for it to fully converge and the inverse covariance matrix conver...

  16. Republic of Chile : Country Procurement Assessment Report

    OpenAIRE

    World Bank

    2004-01-01

    Chile's public procurement system is considered generally free of corruption, supported by probity of the civil servants, decentralization, and good budgetary and control systems. However, it is affected by deficiencies that the government recognizes, and is taking action to overcome, particularly with respect to procurement of goods and services. There is no unified comprehensive, and pub...

  17. DEZVOLTAREA CONTEMPORANĂ A TURISMULUI DIN CHILE

    Directory of Open Access Journals (Sweden)

    Maria-Mihaela Győri

    2011-01-01

    Full Text Available The contemporary development of the Chilean Tourism sector is analyzed mainly on thebasis of data supplied by the National Service of Tourism in Chile. Figures on inboundtourism, domestic tourism, lodging, employment, receipts, as well as the existing structurewithin the sector, were taken into consideration for the investigated period of 1999-2006.

  18. Statistical analysis of wind energy in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Watts, David [Pontificia Universidad Catolica de Chile, Departamento de Ingenieria Electrica, Av. Vicuna Mackenna 4860, Macul, Santiago (Chile); The University of Wisconsin-Madison, 1415 Engineering Drive, WI-53706 (United States); Jara, Danilo [Pontificia Universidad Catolica de Chile, Departamento de Ingenieria Electrica, Av. Vicuna Mackenna 4860, Macul, Santiago (Chile)

    2011-05-15

    Bearing in mind the current and pressing need for an update of the existing Chilean power supply system - which has been remarkably influenced by new requirements - the search for new energy supply sources has become a top priority. The wind resource, vis-a-vis its associated mature technology features and its apparent availability throughout Chile, comes forward as a feasible option likely to play a more important role in any future national energy generation matrix. With a view to understanding the local wind resource, this document surveys a sample set of wind profiles available in the northern Chile area, thus becoming the first public survey of this kind. It also tackles theoretical energy production and capacity factors. Those became the basis of the wind modelling we undertook for Chile's participation in COP15. This paper shows wind generation is a suitable option for curbing down Greenhouse Gas Emissions (GHG) in Chile. (author)

  19. Upward trend for Chile; Andenstaat im Aufwind

    Energy Technology Data Exchange (ETDEWEB)

    Korneffel, Peter

    2010-03-15

    After an economic boom of 20 years, Chile may soon experience a change of paradigm in an economy based on renewable energy sources. Wind power is booming, and hydroelectric power is going strong as well. It will depend on the new government to see that the process of change continues. (orig.)

  20. Sistema de salud de Chile The health system of Chile

    Directory of Open Access Journals (Sweden)

    Víctor Becerril-Montekio

    2011-01-01

    Full Text Available En este trabajo se describe el sistema de salud de Chile, incluyendo su estructura, financiamiento, beneficiarios y recursos físicos, materiales y humanos de los que dispone. Este sistema está compuesto por dos sectores, público y privado. El sector público está formado por todos los organismos que constituyen el Sistema Nacional de Servicios de Salud y cubre aproximadamente a 70% de la población, incluyendo a los pobres del campo y las ciudades, la clase media baja y los jubilados, así como los profesionales y técnicos. El sector privado cubre aproximadamente a 17.5% de la población perteneciente a los grupos sociales de mayores ingresos. Un pequeño sector de la población, perteneciente a la clase alta, realiza pagos directos de bolsillo a proveedores privados de servicios de atención a la salud. Alrededor de 10% de la población está cubierta por otras agencias públicas, fundamentalmente los Servicios de Salud de las Fuerzas Armadas. Recientemente el sistema se reformó creando el Régimen General de Garantías en Salud, que establece un Sistema Universal con Garantías Explícitas que se tradujo, en 2005, en el Plan de Acceso Universal con Garantías Explícitas (AUGE, que garantiza el acceso oportuno a servicios de calidad para 56 problemas de salud, incluyendo cáncer en niños, cáncer de mama, trastornos isquémicos del corazón, VIH/SIDA y diabetes.This paper describes the Chilean health system, including its structure, financing, beneficiaries, and its physical, material and human resources. This system has two sectors, public and private. The public sector comprises all the organisms that constitute the National System of Health Services, which covers 70% of the population, including the rural and urban poor, the low middle-class, the retired, and the self-employed professionals and technicians.The private sector covers 17.5% of the population, mostly the upper middle-class and the high-income population. A small

  1. A dichotomous species of Codium (Bryopsidales, Chlorophyta is colonizing northern Chile Una especie dicotómica de Codium (Bryopsidales, Chlorophyta está colonizando el norte de Chile

    Directory of Open Access Journals (Sweden)

    ALEJANDRA GONZÁLEZ

    2004-06-01

    Full Text Available In late 2001 and early 2002, a dichotomous species of Codium appeared colonizing the low intertidal and shallow subtidal bottoms of Caldera Bay, northern Chile (27° 03’ S, 70° 51’ W. Due to the ecological and economic impact the species is having in Caldera Bay and its potential spread along the Chilean coastline, we studied the taxonomic identity of the species and examined its relationships with other dichotomous species of Codium reported for temperate Pacific South America. Morphological analyses suggest that the seaweeds from Caldera Bay belong to Codium fragile (Suringar Hariot. Not only is there strong agreement in internal and external morphological characters, but among all the species reported for Peru and Chile, this is the only one exhibiting utricles with rounded, apiculate tip terminating in a mucron. This species has a broad geographic distribution in temperate waters. In Chile it was known only from the coasts of Valdivia to the Straits of Magellan (39° 48’ S, 73° 26’ W to 53° 10’ S, 73° 49’ W. This is the first record of C. fragile in northern Chile, and this study discusses several alternative hypotheses for the presence of the species into this area. The morphological characteristics of the material collected in Caldera partially agree with diagnostic characters known for C. fragile subspecies tasmanicum and C. fragile subspecies tomentosoides. However, the rapid population spread of the species in northern Chile, and recent molecular analysis support the identification of this form as the invasive C. fragile subspecies tomentosoidesA fines de 2001 y principio de 2002, apareció en el norte de Chile una especie del género Codium, de morfología dicotómica, colonizando los niveles intermareales y submareales de la Bahía de Caldera (27° 03’ S, 70° 51’ O. Debido al impacto ecológico y económico que ha provocado esta especie en la Bahía de Caldera y a su dispersión potencial a lo largo de la costa de

  2. Party Change in Chile in Comparative Perspective

    Directory of Open Access Journals (Sweden)

    Alan Angell

    2003-01-01

    Full Text Available Abstract This article looks at the changes in party systems generally in modern democracies, and argues that many trends observed internationally - growing mistrust of parties, growing electoral de-alignment - are also observed in Chile. Hence any analysis of party change in Chile has to take into account what is happening in other countries with well-established party systems. The article argues that the comparison with the past tends to be limited to the exceptional 1964-1973 period and that a more extended analysis points to many continuities in the Chilean party system. Competing arguments over whether there is new party cleavage in Chile based on the opposition between support for authoritarianism or support for democracy are also examined*.Resumen Este artículo estudia los cambios generales en los sistemas de partidos en las democracias modernas y argumenta que muchas de las tendencias que se observan internacionalmente -como el aumento en la desconfianza en los partidos, o desalineaciones electorales cada vez mayores- también se observan en Chile. De esta forma, cualquier análisis de cambios en el sistema de partidos de Chile tiene que considerar lo que está sucediendo en otros países con sistemas de partidos bien establecidos. El artículo postula que la comparación del sistema de partidos chileno con el pasado reciente tiende a estar limitado al período excepcional 1964-1973 y que un análisis más extendido implicaría muchas más continuidades de las esperadas. También se cuestiona las nuevas discusiones sobre si existe o no una nueva fisura partidaria, basada en la oposición entre el apoyo y rechazo al sistema autoritario, o el apoyo a la democracia.

  3. Covariant non-commutative space–time

    Directory of Open Access Journals (Sweden)

    Jonathan J. Heckman

    2015-05-01

    Full Text Available We introduce a covariant non-commutative deformation of 3+1-dimensional conformal field theory. The deformation introduces a short-distance scale ℓp, and thus breaks scale invariance, but preserves all space–time isometries. The non-commutative algebra is defined on space–times with non-zero constant curvature, i.e. dS4 or AdS4. The construction makes essential use of the representation of CFT tensor operators as polynomials in an auxiliary polarization tensor. The polarization tensor takes active part in the non-commutative algebra, which for dS4 takes the form of so(5,1, while for AdS4 it assembles into so(4,2. The structure of the non-commutative correlation functions hints that the deformed theory contains gravitational interactions and a Regge-like trajectory of higher spin excitations.

  4. Supergeometry in locally covariant quantum field theory

    CERN Document Server

    Hack, Thomas-Paul; Schenkel, Alexander

    2015-01-01

    In this paper we analyze supergeometric locally covariant quantum field theories. We develop suitable categories SLoc of super-Cartan supermanifolds, which generalize Lorentz manifolds in ordinary quantum field theory, and show that, starting from a few representation theoretic and geometric data, one can construct a functor A : SLoc --> S*Alg to the category of super-*-algebras which can be interpreted as a non-interacting super-quantum field theory. This construction turns out to disregard supersymmetry transformations as the morphism sets in the above categories are too small. We then solve this problem by using techniques from enriched category theory, which allows us to replace the morphism sets by suitable morphism supersets that contain supersymmetry transformations as their higher superpoints. We construct super-quantum field theories in terms of enriched functors eA : eSLoc --> eS*Alg between the enriched categories and show that supersymmetry transformations are appropriately described within the en...

  5. Baryon Spectrum Analysis using Covariant Constraint Dynamics

    Science.gov (United States)

    Whitney, Joshua; Crater, Horace

    2012-03-01

    The energy spectrum of the baryons is determined by treating each of them as a three-body system with the interacting forces coming from a set of two-body potentials that depend on both the distance between the quarks and the spin and orbital angular momentum coupling terms. The Two Body Dirac equations of constraint dynamics derived by Crater and Van Alstine, matched with the quasipotential formalism of Todorov as the underlying two-body formalism are used, as well as the three-body constraint formalism of Sazdjian to integrate the three two-body equations into a single relativistically covariant three body equation for the bound state energies. The results are analyzed and compared to experiment using a best fit method and several different algorithms, including a gradient approach, and Monte Carlo method. Results for all well-known baryons are presented and compared to experiment, with good accuracy.

  6. Covariant Hyperbolization of Force-free Electrodynamics

    CERN Document Server

    Carrasco, Federico

    2016-01-01

    Force-Free Flectrodynamics (FFE) is a non-linear system of equations modeling the evolution of the electromagnetic field, in the presence of a magnetically dominated relativistic plasma. This configuration arises on several astrophysical scenarios, which represent exciting laboratories to understand physics in extreme regimes. We show that this system, when restricted to the correct constraint submanifold, is symmetric hyperbolic. In numerical applications is not feasible to keep the system in that submanifold, and so, it is necessary to analyze its structure first in the tangent space of that submanifold and then in a whole neighborhood of it. As already shown by Pfeiffer, a direct (or naive) formulation of this system (in the whole tangent space) results in a weakly hyperbolic system of evolution equations for which well-possednes for the initial value formulation does not follows. Using the generalized symmetric hyperbolic formalism due to Geroch, we introduce here a covariant hyperbolization for the FFE s...

  7. Multisymplectic formalism and the covariant phase

    CERN Document Server

    Hélein, Frédéric

    2011-01-01

    The formulation of a relativistic dynamical problem as a system of Hamilton equations by respecting the principles of Relativity is a delicate task, because in their classical form the Hamilton equations require the use of a time coordinate, which of course contradicts the Relativity. Two interesting solutions have been proposed during the last century: the covariant phase space and the multisymplectic formalism. These two approaches were inspired at the beginning by different points of view. However, as shown by works by Kijowski-Szczyrba, Forger-Romero and Vitagliano, a synthetic vision of the two theories leads probably to the most satisfactory answer to the basic question of understanding the Hamiltonian structure of relativistic fields theory.

  8. Holographic bound in covariant loop quantum gravity

    CERN Document Server

    Tamaki, Takashi

    2016-01-01

    We investigate puncture statistics based on the covariant area spectrum in loop quantum gravity. First, we consider Maxwell-Boltzmann statistics with a Gibbs factor for punctures. We establish formulae which relate physical quantities such as horizon area to the parameter characterizing holographic degrees of freedom. We also perform numerical calculations and obtain consistency with these formulae. These results tell us that the holographic bound is satisfied in the large area limit and correction term of the entropy-area law can be proportional to the logarithm of the horizon area. Second, we also consider Bose-Einstein statistics and show that the above formulae are also useful in this case. By applying the formulae, we can understand intrinsic features of Bose-Einstein condensate which corresponds to the case when the horizon area almost consists of punctures in the ground state. When this phenomena occurs, the area is approximately constant against the parameter characterizing the temperature. When this ...

  9. Covariant Lyapunov analysis of chaotic Kolmogorov flows.

    Science.gov (United States)

    Inubushi, Masanobu; Kobayashi, Miki U; Takehiro, Shin-ichi; Yamada, Michio

    2012-01-01

    Hyperbolicity is an important concept in dynamical system theory; however, we know little about the hyperbolicity of concrete physical systems including fluid motions governed by the Navier-Stokes equations. Here, we study numerically the hyperbolicity of the Navier-Stokes equation on a two-dimensional torus (Kolmogorov flows) using the method of covariant Lyapunov vectors developed by Ginelli et al. [Phys. Rev. Lett. 99, 130601 (2007)]. We calculate the angle between the local stable and unstable manifolds along an orbit of chaotic solution to evaluate the hyperbolicity. We find that the attractor of chaotic Kolmogorov flows is hyperbolic at small Reynolds numbers, but that smaller angles between the local stable and unstable manifolds are observed at larger Reynolds numbers, and the attractor appears to be nonhyperbolic at a certain Reynolds numbers. Also, we observed some relations between these hyperbolic properties and physical properties such as time correlation of the vorticity and the energy dissipation rate.

  10. Flavour Covariant Formalism for Resonant Leptogenesis

    CERN Document Server

    Dev, P S Bhupal; Pilaftsis, Apostolos; Teresi, Daniele

    2014-01-01

    We present a fully flavour-covariant formalism for transport phenomena and apply it to study the flavour-dynamics of Resonant Leptogenesis (RL). We show that this formalism provides a complete and unified description of RL, consistently accounting for three distinct physical phenomena: (i) resonant mixing and (ii) coherent oscillations between different heavy-neutrino flavours, as well as (iii) quantum decoherence effects in the charged-lepton sector. We describe the necessary emergence of higher-rank tensors in flavour space, arising from the unitarity cuts of partial self-energies. Finally, we illustrate the importance of this formalism within a minimal Resonant $\\tau$-Genesis model by showing that, with the inclusion of all flavour effects in a consistent way, the final lepton asymmetry can be enhanced by up to an order of magnitude, when compared to previous partially flavour-dependent treatments.

  11. Universal Gravitation as Lorentz-covariant Dynamics

    CERN Document Server

    Kauffmann, Steven Kenneth

    2014-01-01

    Einstein's equivalence principle implies that the acceleration of a particle in a "specified" gravitational field is independent of its mass. While this is certainly true to great accuracy for bodies we observe in the Earth's gravitational field, a hypothetical body of mass comparable to the Earth's would perceptibly cause the Earth to fall toward it, which would feed back into the strength as a function of time of the Earth's gravitational field affecting that body. In short, Einstein's equivalence principle isn't exact, but is an approximation that ignores recoil of the "specified" gravitational field, which sheds light on why general relativity has no clearly delineated native embodiment of conserved four-momentum. Einstein's 1905 relativity of course doesn't have the inexactitudes he unwittingly built into GR, so it is natural to explore a Lorentz-covariant gravitational theory patterned directly on electromagnetism, wherein a system's zero-divergence overall stress-energy, including all gravitational fee...

  12. On the Validity of Covariate Adjustment for Estimating Causal Effects

    CERN Document Server

    Shpitser, Ilya; Robins, James M

    2012-01-01

    Identifying effects of actions (treatments) on outcome variables from observational data and causal assumptions is a fundamental problem in causal inference. This identification is made difficult by the presence of confounders which can be related to both treatment and outcome variables. Confounders are often handled, both in theory and in practice, by adjusting for covariates, in other words considering outcomes conditioned on treatment and covariate values, weighed by probability of observing those covariate values. In this paper, we give a complete graphical criterion for covariate adjustment, which we term the adjustment criterion, and derive some interesting corollaries of the completeness of this criterion.

  13. Kriging approach for the experimental cross-section covariances estimation

    Directory of Open Access Journals (Sweden)

    Garlaud A.

    2013-03-01

    Full Text Available In the classical use of a generalized χ2 to determine the evaluated cross section uncertainty, we need the covariance matrix of the experimental cross sections. The usual propagation error method to estimate the covariances is hardly usable and the lack of data prevents from using the direct empirical estimator. We propose in this paper to apply the kriging method which allows to estimate the covariances via the distances between the points and with some assumptions on the covariance matrix structure. All the results are illustrated with the 2555Mn nucleus measurements.

  14. Baryon Wave Functions in Covariant Relativistic Quark Models

    CERN Document Server

    Dillig, M

    2002-01-01

    We derive covariant baryon wave functions for arbitrary Lorentz boosts. Modeling baryons as quark-diquark systems, we reduce their manifestly covariant Bethe-Salpeter equation to a covariant 3-dimensional form by projecting on the relative quark-diquark energy. Guided by a phenomenological multigluon exchange representation of a covariant confining kernel, we derive for practical applications explicit solutions for harmonic confinement and for the MIT Bag Model. We briefly comment on the interplay of boosts and center-of-mass corrections in relativistic quark models.

  15. Relativistic Covariance and Quark-Diquark Wave Functions

    CERN Document Server

    Dillig, M

    2006-01-01

    We derive covariant wave functions for hadrons composed of two constituents for arbitrary Lorentz boosts. Focussing explicitly on baryons as quark-diquark systems, we reduce their manifestly covariant Bethe-Salpeter equation to covariant 3-dimensional forms by projecting on the relative quark-diquark energy. Guided by a phenomenological multi gluon exchange representation of covariant confining kernels, we derive explicit solutions for harmonic confinement and for the MIT Bag Model. We briefly sketch implications of breaking the spherical symmetry of the ground state and the transition from the instant form to the light cone via the infinite momentum frame.

  16. A taxonomic study of Bali and Lombok Begonia (Begoniaceae

    Directory of Open Access Journals (Sweden)

    Deden Girmansyah

    2009-12-01

    Full Text Available GIRMANSYAH, DEDEN. 2009. A taxonomic study of Bali and Lombok Begonia (Begoniaceae. Reinwardtia 12(5: 419–434. — A taxonomic study of Bali and Lombok Begonia was based on an investigation of morphological characters from 60 specimens in Herbarium Bogoriense. This study shows that there are 8 species that can be recognized: three species already in the genus (Begonia coriacea, B. longifolia, and B. tenuifolia and five new (Begonia baliensis, B. lempuyangensis, B. pseudomuricata, B. multibracteata, and B. lombokensis.

  17. Methods for estimation of covariance matrices and covariance components for the Hanford Waste Vitrification Plant Process

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, M.F.; Piepel, G.F.; Simpson, D.B.

    1996-03-01

    The high-level waste (HLW) vitrification plant at the Hanford Site was being designed to transuranic and high-level radioactive waste in borosilicate class. Each batch of plant feed material must meet certain requirements related to plant performance, and the resulting class must meet requirements imposed by the Waste Acceptance Product Specifications. Properties of a process batch and the resultlng glass are largely determined by the composition of the feed material. Empirical models are being developed to estimate some property values from data on feed composition. Methods for checking and documenting compliance with feed and glass requirements must account for various types of uncertainties. This document focuses on the estimation. manipulation, and consequences of composition uncertainty, i.e., the uncertainty inherent in estimates of feed or glass composition. Three components of composition uncertainty will play a role in estimating and checking feed and glass properties: batch-to-batch variability, within-batch uncertainty, and analytical uncertainty. In this document, composition uncertainty and its components are treated in terms of variances and variance components or univariate situations, covariance matrices and covariance components for multivariate situations. The importance of variance and covariance components stems from their crucial role in properly estimating uncertainty In values calculated from a set of observations on a process batch. Two general types of methods for estimating uncertainty are discussed: (1) methods based on data, and (2) methods based on knowledge, assumptions, and opinions about the vitrification process. Data-based methods for estimating variances and covariance matrices are well known. Several types of data-based methods exist for estimation of variance components; those based on the statistical method analysis of variance are discussed, as are the strengths and weaknesses of this approach.

  18. Covariant Spectator Theory: Foundations and Applications A Mini-Review of the Covariant Spectator Theory

    Energy Technology Data Exchange (ETDEWEB)

    Alfred Stadler, Franz Gross

    2010-10-01

    We provide a short overview of the Covariant Spectator Theory and its applications. The basic ideas are introduced through the example of a {phi}{sup 4}-type theory. High-precision models of the two-nucleon interaction are presented and the results of their use in calculations of properties of the two- and three-nucleon systems are discussed. A short summary of applications of this framework to other few-body systems is also presented.

  19. How General Relativity and Lorentz Covariance Arise from the Spatially Covariant Effective Field Theory of the Transverse, Traceless Graviton

    CERN Document Server

    Khoury, Justin; Tolley, Andrew J

    2014-01-01

    Traditional derivations of general relativity from the graviton degrees of freedom assume space-time Lorentz covariance as an axiom. In this essay, we survey recent evidence that general relativity is the unique spatially-covariant effective field theory of the transverse, traceless graviton degrees of freedom. The Lorentz covariance of general relativity, having not been assumed in our analysis, is thus plausibly interpreted as an accidental or emergent symmetry of the gravitational sector. From this point of view, Lorentz covariance is a necessary feature of low-energy graviton dynamics, not a property of space-time. This result has revolutionary implications for fundamental physics.

  20. Covariant and quasi-covariant quantum dynamics in Robertson-Walker space-times

    CERN Document Server

    Buchholz, D; Summers, S J; Buchholz, Detlev; Mund, Jens; Summers, Stephen J.

    2002-01-01

    We propose a canonical description of the dynamics of quantum systems on a class of Robertson-Walker space-times. We show that the worldline of an observer in such space-times determines a unique orbit in the local conformal group SO(4,1) of the space-time and that this orbit determines a unique transport on the space-time. For a quantum system on the space-time modeled by a net of local algebras, the associated dynamics is expressed via a suitable family of ``propagators''. In the best of situations, this dynamics is covariant, but more typically the dynamics will be ``quasi-covariant'' in a sense we make precise. We then show by using our technique of ``transplanting'' states and nets of local algebras from de Sitter space to Robertson-Walker space that there exist quantum systems on Robertson-Walker spaces with quasi-covariant dynamics. The transplanted state is locally passive, in an appropriate sense, with respect to this dynamics.

  1. A taxonomic revision of Germainia (Andropogoneae: Poaceae) in Thailand

    NARCIS (Netherlands)

    Teerawatananon, A.; Sungkaew, S.; Boontia, V.; Hodkinson, T.R.

    2012-01-01

    A taxonomic revision of the genus Germainia (Andropogoneae, Poaceae) in Thailand is presented based on herbarium and field studies, including evidence from morphology, habitats and geographical distribution. Six of the nine recognized Germainia species are found in Thailand. We include a key to the

  2. Developing green supply chain management strategies: A taxonomic approach

    Directory of Open Access Journals (Sweden)

    Michael Mutingi

    2013-06-01

    Full Text Available Purpose: The objective of this research is to explore the empirical green supply chain activities found in literature, and to develop a taxonomic framework that can be used for formulating appropriate strategies for green supply chains, based on characteristic dimensions for the green supply chain. Design/methodology/approach: The taxonomic framework is developed through (i analysis of green supply chain activities found in existing empirical work or case studies recorded in literature, (ii identification of key dimensions that influence green supply chain management strategies, and (iii development of a taxonomic scheme for selecting or developing green strategies. Findings: The paper finds that this study yielded: a set of three characteristic dimensions that influence strategic green supply chain management, and a guided structured approach selecting appropriate green strategies, providing managerial insights. Research limitations/implications: This paper shows that future work includes development of specific performance management indices according to the taxonomy of green strategies developed in this study. Practical implications: This research provided a practical guided approach that enhances appropriate formulation of green strategies for green supply chain management, while providing sound managerial insights for the supply chain decision maker. The choice of supply chain strategy directly impacts the overall environmental, economic and operations performance of the supply chain. Originality/value: This study presents to supply chain decision makers a new taxonomic framework that simplifies and enhances the formulation of green strategies, and to researchers a comparative understanding of various strategies applicable to green supply chains.

  3. A synopsis of taxonomic changes in Aporosa Blume (Euphorbiaceae)

    NARCIS (Netherlands)

    Schot, Anne M.

    1995-01-01

    Some major nomenclatural and taxonomic changes in Aporosa Blume are treated, i.e., the spelling of the genus name, some new combinations, and descriptions of four new species of from West Malesia, six from New Guinea, and two new varieties from West Malesia. Notes on a number of often misunderstood

  4. WEVOTE: Weighted Voting Taxonomic Identification Method of Microbial Sequences

    Science.gov (United States)

    Metwally, Ahmed A.; Dai, Yang; Finn, Patricia W.; Perkins, David L.

    2016-01-01

    Background Metagenome shotgun sequencing presents opportunities to identify organisms that may prevent or promote disease. The analysis of sample diversity is achieved by taxonomic identification of metagenomic reads followed by generating an abundance profile. Numerous tools have been developed based on different design principles. Tools achieving high precision can lack sensitivity in some applications. Conversely, tools with high sensitivity can suffer from low precision and require long computation time. Methods In this paper, we present WEVOTE (WEighted VOting Taxonomic idEntification), a method that classifies metagenome shotgun sequencing DNA reads based on an ensemble of existing methods using k-mer-based, marker-based, and naive-similarity based approaches. Our evaluation on fourteen benchmarking datasets shows that WEVOTE improves the classification precision by reducing false positive annotations while preserving a high level of sensitivity. Conclusions WEVOTE is an efficient and automated tool that combines multiple individual taxonomic identification methods to produce more precise and sensitive microbial profiles. WEVOTE is developed primarily to identify reads generated by MetaGenome Shotgun sequencing. It is expandable and has the potential to incorporate additional tools to produce a more accurate taxonomic profile. WEVOTE was implemented using C++ and shell scripting and is available at www.github.com/aametwally/WEVOTE. PMID:27683082

  5. Taxonomía de la literatura oral kuna

    OpenAIRE

    Prestán, Arnulfo

    2016-01-01

    El presente trabajo trata de descifrar, grosso modo, la taxonomía de la literatura oral kuna denominada ikar que significa tratado o camino y se especifica anteponiendo un sustantivo, por ejemplo, pap ikar que significa tratado de Dios; ina ikar, tratado de medicina, etc.

  6. Effects of land use on taxonomic and functional diversity

    DEFF Research Database (Denmark)

    Hevia, Violeta; Carmona, Carlos P.; Azcárate, Francisco M.;

    2016-01-01

    Land-use change is the major driver of biodiversity loss. However, taxonomic diversity (TD) and functional diversity (FD) might respond differently to land-use change, and this response might also vary depending on the biotic group being analysed. In this study, we compare the TD and FD of four...

  7. Thermoluminescence properties of Chile Guajillo (paprika) Mexicano

    Energy Technology Data Exchange (ETDEWEB)

    Kitis, G. [Nuclear Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)]. E-mail: gkitis@auth.gr; Cruz Zaragoza, E. [Institute of Nuclear Science, UNAM, PO Box 70-753, Mexico DF (Mexico); Furetta, C. [Physics Department, University La Sapienza, P.le A. Moro 2. 00187 Rome (Italy)

    2005-08-01

    The thermoluminescence properties of the inorganic dust extracted from the Chile Guajillo (paprika) Mexicano, were studied in order to verify the possibility of using the TL technique to discriminate between irradiated and non irradiated peppers. The inorganic dust was found to consist of quartz 60%, albite (NaAlSi{sub 3}O{sub 8}) 30%, and ortose (KAlSi{sub 3}O{sub 8}) 10%. Its thermoluminescence dose response covers the wide dose range of 1Gy-10kGy, which was attributed mainly to feldspars. Its high sensitivity and its stability over 10 irradiation-readout cycles allow the application of a single grain-single aliquot regeneration dosimetry in Chile Guajillo (paprika). Evaluations based on trapping parameters show that thermal fading at room temperature for glow-peaks above 180 deg.. C, is not a problem in the dosimetry of paprika.

  8. Metagenomic analysis exploring taxonomic and functional diversity of soil microbial communities in Chilean vineyards and surrounding native forests

    Science.gov (United States)

    2017-01-01

    Mediterranean biomes are biodiversity hotspots, and vineyards are important components of the Mediterranean landscape. Over the last few decades, the amount of land occupied by vineyards has augmented rapidly, thereby increasing threats to Mediterranean ecosystems. Land use change and agricultural management have important effects on soil biodiversity, because they change the physical and chemical properties of soil. These changes may also have consequences on wine production considering that soil is a key component of terroir. Here, we describe the taxonomic diversity and metabolic functions of bacterial and fungal communities present in forest and vineyard soils in Chile. To accomplish this goal, we collected soil samples from organic vineyards in central Chile and employed a shotgun metagenomic approach to sequence the microbial DNA. Additionally, we studied the surrounding native forest to obtain a baseline of the soil conditions in the area prior to the establishment of the vineyard. Our metagenomic analyses revealed that both habitats shared most of the soil microbial species. The most abundant genera in the two habitats were the bacteria Candidatus Solibacter and Bradyrhizobium and the fungus Gibberella. Our results suggest that the soil microbial communities are similar in these forests and vineyards. Therefore, we hypothesize that native forests surrounding the vineyards may be acting as a microbial reservoir buffering the effects of the land conversion. Regarding the metabolic diversity, we found that genes pertaining to the metabolism of amino acids, fatty acids, and nucleotides as well as genes involved in secondary metabolism were enriched in forest soils. On the other hand, genes related to miscellaneous functions were more abundant in vineyard soils. These results suggest that the metabolic function of microbes found in these habitats differs, though differences are not related to taxonomy. Finally, we propose that the implementation of

  9. On the bilinear covariants associated to mass dimension one spinors

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.M.H. da; Villalobos, C.H.C.; Rogerio, R.J.B. [DFQ, UNESP, Guaratingueta, SP (Brazil); Scatena, E. [Universidade Federal de Santa Catarina-CEE, Blumenau, SC (Brazil)

    2016-10-15

    In this paper we approach the issue of Clifford algebra basis deformation, allowing for bilinear covariants associated to Elko spinors which satisfy the Fierz-Pauli-Kofink identities. We present a complete analysis of covariance, taking into account the involved dual structure associated to Elko spinors. Moreover, the possible generalizations to the recently presented new dual structure are performed. (orig.)

  10. On the bilinear covariants associated to mass dimension one spinors

    CERN Document Server

    da Silva, J M Hoff; Rogerio, R J Bueno; Scatena, E

    2016-01-01

    In this paper we approach the issue of Clifford algebra basis deformation, allowing for bilinear covariants associated to Elko spinors which satisfy the Fierz-Pauli-Kofink identities. We present a complete analysis of covariance, taking into account the involved dual structure associated to Elko. Moreover, the possible generalizations to the recently presented new dual structure are performed.

  11. A pure S-wave covariant model for the nucleon

    CERN Document Server

    Gross, F; Peña, M T; Gross, Franz

    2006-01-01

    Using the manifestly covariant spectator theory, and modeling the nucleon as a system of three constituent quarks with their own electromagnetic structure, we show that all four nucleon electromagnetic form factors can be very well described by a manifestly covariant nucleon wave function with zero orbital angular momentum.

  12. Covariation Is a Poor Measure of Molecular Coevolution.

    Science.gov (United States)

    Talavera, David; Lovell, Simon C; Whelan, Simon

    2015-09-01

    Recent developments in the analysis of amino acid covariation are leading to breakthroughs in protein structure prediction, protein design, and prediction of the interactome. It is assumed that observed patterns of covariation are caused by molecular coevolution, where substitutions at one site affect the evolutionary forces acting at neighboring sites. Our theoretical and empirical results cast doubt on this assumption. We demonstrate that the strongest coevolutionary signal is a decrease in evolutionary rate and that unfeasibly long times are required to produce coordinated substitutions. We find that covarying substitutions are mostly found on different branches of the phylogenetic tree, indicating that they are independent events that may or may not be attributable to coevolution. These observations undermine the hypothesis that molecular coevolution is the primary cause of the covariation signal. In contrast, we find that the pairs of residues with the strongest covariation signal tend to have low evolutionary rates, and that it is this low rate that gives rise to the covariation signal. Slowly evolving residue pairs are disproportionately located in the protein's core, which explains covariation methods' ability to detect pairs of residues that are close in three dimensions. These observations lead us to propose the "coevolution paradox": The strength of coevolution required to cause coordinated changes means the evolutionary rate is so low that such changes are highly unlikely to occur. As modern covariation methods may lead to breakthroughs in structural genomics, it is critical to recognize their biases and limitations.

  13. Validity of covariance models for the analysis of geographical variation

    DEFF Research Database (Denmark)

    Guillot, Gilles; Schilling, Rene L.; Porcu, Emilio

    2014-01-01

    1. Due to the availability of large molecular data-sets, covariance models are increasingly used to describe the structure of genetic variation as an alternative to more heavily parametrised biological models. 2. We focus here on a class of parametric covariance models that received sustained...

  14. Perturbative approach to covariance matrix of the matter power spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, Irshad [Fermilab; Seljak, Uros [UC, Berkeley, Astron. Dept.; Vlah, Zvonimir [Stanford U., ITP

    2016-06-30

    We evaluate the covariance matrix of the matter power spectrum using perturbation theory up to dominant terms at 1-loop order and compare it to numerical simulations. We decompose the covariance matrix into the disconnected (Gaussian) part, trispectrum from the modes outside the survey (beat coupling or super-sample variance), and trispectrum from the modes inside the survey, and show how the different components contribute to the overall covariance matrix. We find the agreement with the simulations is at a 10\\% level up to $k \\sim 1 h {\\rm Mpc^{-1}}$. We show that all the connected components are dominated by the large-scale modes ($k<0.1 h {\\rm Mpc^{-1}}$), regardless of the value of the wavevectors $k,\\, k'$ of the covariance matrix, suggesting that one must be careful in applying the jackknife or bootstrap methods to the covariance matrix. We perform an eigenmode decomposition of the connected part of the covariance matrix, showing that at higher $k$ it is dominated by a single eigenmode. The full covariance matrix can be approximated as the disconnected part only, with the connected part being treated as an external nuisance parameter with a known scale dependence, and a known prior on its variance for a given survey volume. Finally, we provide a prescription for how to evaluate the covariance matrix from small box simulations without the need to simulate large volumes.

  15. Theory of Covariance Equivalent ARMAV Models of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Andersen, P.; Brincker, Rune; Kirkegaard, Poul Henning

    In this paper the theoretical background for using covariance equivalent ARMAV models in modal analysis is discussed. It is shown how to obtain a covariance equivalent ARMA model for a univariate linear second order continuous-time system excited by Gaussian white noise. This result is generalize...

  16. Theory of Covariance Equivalent ARMAV Models of Civil Engineering Structures

    DEFF Research Database (Denmark)

    Andersen, P.; Brincker, Rune; Kirkegaard, Poul Henning

    1996-01-01

    In this paper the theoretical background for using covariance equivalent ARMAV models in modal analysis is discussed. It is shown how to obtain a covariance equivalent ARMA model for a univariate linear second order continous-time system excited by Gaussian white noise. This result is generalized...

  17. Soviet Policy in Cuba and Chile.

    Science.gov (United States)

    1980-05-06

    document dated June 30, 1973, instructing all Communist Party members in Santiago to secure arms and to evacuate the upper class barrio alto in case of...loans. (Other reports indicated a figure of $100 million.) It was also announced in Santiago that the Soviet Union had granted $108 million for long-term...Chile at Rojo, Santiago : Universidad Tecnica del Estado, 1971. See also Luis Corvalan, El Camino de Victoria, Santiago : Impresova Horizonte, 1971, pp

  18. Volby v Chile 2009

    OpenAIRE

    2010-01-01

    Twenty years has passed from dissolution of authoritarian regime of Augusto Pinochet and in the presidential election 2009/2010 in Chile the right-wing candidate won. The era of continuous government of centre-leftist coalition, that administrated country from the period of transition, was ended off. The thesis focuses on the analysis of presidential and parliamentary elections, in the first place on the question what was the matter of triumph of the opposite candidate in the presidential ele...

  19. Tackling Social Exclusion: Evidence from Chile

    OpenAIRE

    2014-01-01

    This paper studies an innovative welfare program in Chile that combines a period of frequent home visits to households in extreme poverty, with guaranteed access to social services. Program impacts are identified using a regression discontinuity design, exploring the fact that program eligibility is a discontinuous function of an index of family income and assets. The analysis finds strong and lasting impacts of the program on the take-up of subsidies and employment services. These impacts ar...

  20. High-dimensional covariance matrix estimation in approximate factor models

    CERN Document Server

    Fan, Jianqing; Mincheva, Martina; 10.1214/11-AOS944

    2012-01-01

    The variance--covariance matrix plays a central role in the inferential theories of high-dimensional factor models in finance and economics. Popular regularization methods of directly exploiting sparsity are not directly applicable to many financial problems. Classical methods of estimating the covariance matrices are based on the strict factor models, assuming independent idiosyncratic components. This assumption, however, is restrictive in practical applications. By assuming sparse error covariance matrix, we allow the presence of the cross-sectional correlation even after taking out common factors, and it enables us to combine the merits of both methods. We estimate the sparse covariance using the adaptive thresholding technique as in Cai and Liu [J. Amer. Statist. Assoc. 106 (2011) 672--684], taking into account the fact that direct observations of the idiosyncratic components are unavailable. The impact of high dimensionality on the covariance matrix estimation based on the factor structure is then studi...

  1. Newton law in covariant unimodular $F(R)$ gravity

    CERN Document Server

    Nojiri, S; Oikonomou, V K

    2016-01-01

    We propose a covariant ghost-free unimodular $F(R)$ gravity theory, which contains a three-form field and study its structure using the analogy of the proposed theory with a quantum system which describes a charged particle in uniform magnetic field. Newton's law in non-covariant unimodular $F(R)$ gravity as well as in unimodular Einstein gravity is derived and it is shown to be just the same as in General Relativity. The derivation of Newton's law in covariant unimodular $F(R)$ gravity shows that it is modified precisely in the same way as in the ordinary $F(R)$ theory. We also demonstrate that the cosmology of a Friedmann-Robertson-Walker background, is equivalent in the non-covariant and covariant formulations of unimodular $F(R)$ theory.

  2. Gaussian covariance matrices for anisotropic galaxy clustering measurements

    CERN Document Server

    Grieb, Jan Niklas; Salazar-Albornoz, Salvador; Vecchia, Claudio dalla

    2015-01-01

    Measurements of the redshift-space galaxy clustering have been a prolific source of cosmological information in recent years. In the era of precision cosmology, accurate covariance estimates are an essential step for the validation of galaxy clustering models of the redshift-space two-point statistics. For cases where only a limited set of simulations is available, assessing the data covariance is not possible or only leads to a noisy estimate. Also, relying on simulated realisations of the survey data means that tests of the cosmology dependence of the covariance are expensive. With these two points in mind, this work aims at presenting a simple theoretical model for the linear covariance of anisotropic galaxy clustering observations with synthetic catalogues. Considering the Legendre moments (`multipoles') of the two-point statistics and projections into wide bins of the line-of-sight parameter (`clustering wedges'), we describe the modelling of the covariance for these anisotropic clustering measurements f...

  3. The epidemiology of tuberculosis in Chile.

    Science.gov (United States)

    1985-01-01

    Chile's tuberculosis morbidity notification statistics suggest that there has been a 3% average annual decrease in tuberculosis cases in the last 5 years (1978-82). In addition, over the period 1974-83, there was a 50% decline in the number of deaths from tuberculosis. In 1982, there were 6941 recorded cases of tuberculosis in Chile, only 6.5% of which involved children under 15 years of age; in that same year, there were 984 deaths from tuberculosis, 14.4% of which occurred in children. The majority of cases reported (78%) involve pulmonary tuberculosis. Over 90% of children under 15 years of age are covered by Bacille Calmette-Guerin (BCG) vaccination. This was achieved by immunizing 91% of all newborns, 83% of children in their first year of school, and 98% of those in their final year. Laboratories capable of case-finding now cover 95% of Chile's total area. Since 1975, an average of 47 bacilloscopies have been performed per 1000 consultations. Abandonment of treatment has been reduced to 12% and fewer than 20% of cases require hospitalization. Finally, the introduction of shortened rifampicin treatment has reduced the case-fatality rate from 6% to 3%.

  4. Into the Bulk: A Covariant Approach

    CERN Document Server

    Engelhardt, Netta

    2016-01-01

    I propose a general, covariant way of defining when one region is "deeper in the bulk" than another. This definition is formulated outside of an event horizon (or in the absence thereof) in generic geometries; it may be applied to both points and surfaces, and may be used to compare the depth of bulk points or surfaces relative to a particular boundary subregion or relative to the entire boundary. Using the recently proposed "lightcone cut" formalism, the comparative depth between two bulk points can be determined from the singularity structure of Lorentzian correlators in the dual field theory. I prove that, by this definition, causal wedges of progressively larger regions probe monotonically deeper in the bulk. The definition furthermore matches expectations in pure AdS and in static AdS black holes with isotropic spatial slices, where a well-defined holographic coordinate exists. In terms of holographic RG flow, this new definition of bulk depth makes contact with coarse-graining over both large distances ...

  5. Historical Hamiltonian Dynamics: symplectic and covariant

    CERN Document Server

    Lachieze-Rey, M

    2016-01-01

    This paper presents a "historical" formalism for dynamical systems, in its Hamiltonian version (Lagrangian version was presented in a previous paper). It is universal, in the sense that it applies equally well to time dynamics and to field theories on space-time. It is based on the notion of (Hamiltonian) histories, which are sections of the (extended) phase space bundle. It is developed in the space of sections, in contradistinction with the usual formalism which works in the bundle manifold. In field theories, the formalism remains covariant and does not require a spitting of space-time. It considers space-time exactly in the same manner than time in usual dynamics, both being particular cases of the evolution domain. It applies without modification when the histories (the fields) are forms rather than scalar functions, like in electromagnetism or in tetrad general relativity. We develop a differential calculus in the infinite dimensional space of histories. It admits a (generalized) symplectic form which d...

  6. CMB lens sample covariance and consistency relations

    Science.gov (United States)

    Motloch, Pavel; Hu, Wayne; Benoit-Lévy, Aurélien

    2017-02-01

    Gravitational lensing information from the two and higher point statistics of the cosmic microwave background (CMB) temperature and polarization fields are intrinsically correlated because they are lensed by the same realization of structure between last scattering and observation. Using an analytic model for lens sample covariance, we show that there is one mode, separately measurable in the lensed CMB power spectra and lensing reconstruction, that carries most of this correlation. Once these measurements become lens sample variance dominated, this mode should provide a useful consistency check between the observables that is largely free of sampling and cosmological parameter errors. Violations of consistency could indicate systematic errors in the data and lens reconstruction or new physics at last scattering, any of which could bias cosmological inferences and delensing for gravitational waves. A second mode provides a weaker consistency check for a spatially flat universe. Our analysis isolates the additional information supplied by lensing in a model-independent manner but is also useful for understanding and forecasting CMB cosmological parameter errors in the extended Λ cold dark matter parameter space of dark energy, curvature, and massive neutrinos. We introduce and test a simple but accurate forecasting technique for this purpose that neither double counts lensing information nor neglects lensing in the observables.

  7. General Covariance from the Quantum Renormalization Group

    CERN Document Server

    Shyam, Vasudev

    2016-01-01

    The Quantum renormalization group (QRG) is a realisation of holography through a coarse graining prescription that maps the beta functions of a quantum field theory thought to live on the `boundary' of some space to holographic actions in the `bulk' of this space. A consistency condition will be proposed that translates into general covariance of the gravitational theory in the $D + 1$ dimensional bulk. This emerges from the application of the QRG on a planar matrix field theory living on the $D$ dimensional boundary. This will be a particular form of the Wess--Zumino consistency condition that the generating functional of the boundary theory needs to satisfy. In the bulk, this condition forces the Poisson bracket algebra of the scalar and vector constraints of the dual gravitational theory to close in a very specific manner, namely, the manner in which the corresponding constraints of general relativity do. A number of features of the gravitational theory will be fixed as a consequence of this form of the Po...

  8. New covariant Lagrange formulation for field theories

    CERN Document Server

    Ootsuka, T

    2012-01-01

    A novel approach for Lagrange formulation for field theories is proposed in terms of Kawaguchi geometry (areal metric space). On the extended configuration space M for classical field theory composed of spacetime and field configuration space, one can define a geometrical structure called Kawaguchi areal metric K from the field Lagrangian and (M,K) can be regarded as Kawaguchi manifold. The geometrical action functional is given by K and the dynamics of field is determined by covariant Euler-Lagrange equation derived from the variational principle of the action. The solution to the equation becomes a minimal hypersurface on (M,K) which has the same dimension as spacetime. We propose that this hypersurface is what we should regard as our real spacetime manifold, while the usual way to understand spacetime is to consider it as the parameter spacetime (base manifold) of a fibre bundle. In this way, the dynamics of field and spacetime structure is unified by Kawaguchi geometry. The theory has the property of stro...

  9. Schwinger mechanism in linear covariant gauges

    CERN Document Server

    Aguilar, A C; Papavassiliou, J

    2016-01-01

    In this work we explore the applicability of a special gluon mass generating mechanism in the context of the linear covariant gauges. In particular, the implementation of the Schwinger mechanism in pure Yang-Mills theories hinges crucially on the inclusion of massless bound-state excitations in the fundamental nonperturbative vertices of the theory. The dynamical formation of such excitations is controlled by a homogeneous linear Bethe-Salpeter equation, whose nontrivial solutions have been studied only in the Landau gauge. Here, the form of this integral equation is derived for general values of the gauge-fixing parameter, under a number of simplifying assumptions that reduce the degree of technical complexity. The kernel of this equation consists of fully-dressed gluon propagators, for which recent lattice data are used as input, and of three-gluon vertices dressed by a single form factor, which is modelled by means of certain physically motivated Ans\\"atze. The gauge-dependent terms contributing to this ke...

  10. A fully covariant description of CMB anisotropies

    CERN Document Server

    Dunsby, P K S

    1997-01-01

    Starting from the exact non-linear description of matter and radiation, a fully covariant and gauge-invariant formula for the observed temperature anisotropy of the cosmic microwave background (CBR) radiation, expressed in terms of the electric ($E_{ab}$) and magnetic ($H_{ab}$) parts of the Weyl tensor, is obtained by integrating photon geodesics from last scattering to the point of observation today. This improves and extends earlier work by Russ et al where a similar formula was obtained by taking first order variations of the redshift. In the case of scalar (density) perturbations, $E_{ab}$ is related to the harmonic components of the gravitational potential $\\Phi_k$ and the usual dominant Sachs-Wolfe contribution $\\delta T_R/\\bar{T}_R\\sim\\Phi_k$ to the temperature anisotropy is recovered, together with contributions due to the time variation of the potential (Rees-Sciama effect), entropy and velocity perturbations at last scattering and a pressure suppression term important in low density universes. We a...

  11. Covariance and objectivity in mechanics and turbulence

    CERN Document Server

    Frewer, Michael

    2016-01-01

    Form-invariance (covariance) and frame-indifference (objectivity) are two notions in classical continuum mechanics which have attracted much attention and controversy over the past decades. Particularly in turbulence modelling it seems that there still is a need for clarification. The aim and purpose of this study is fourfold: (i) To achieve consensus in general on definitions and principles when trying to establish an invariant theory for modelling constitutive structures and dynamic processes in mechanics, where special focus is put on the principle of Material Frame-Indifference (MFI). (ii) To show that in constitutive modelling MFI can only be regarded as an approximation that needs to be reduced to a weaker statement when trying to advance it to an axiom of nature. (iii) To convince that in dynamical modelling, as in turbulence, MFI may not be utilized as a modelling guideline, not even in an approximative sense. Instead, its reduced form has to be supplemented by a second, independent axiom that include...

  12. Frame Indifferent (Truly Covariant) Formulation of Electrodynamics

    Science.gov (United States)

    Christov, Christo

    2010-10-01

    The Electromagnetic field is considered from the point of view of mechanics of continuum. It is shown that Maxwell's equations are mathematically strict corollaries form the equation of motions of an elastic incompressible liquid. If the concept of frame-indifference (material invariance) is applied to the model of elastic liquid, then the partial time derivatives have to be replaced by the convective time derivative in the momentum equations, and by the Oldroyd upper-convected derivative in the constitutive relation. The convective/convected terms involve the velocity at a point of the field, and as a result, when deriving the Maxwell form of the equations, one arrives at equations which contain both the terms of Maxwell's equation and the so-called laws of motional EMF: Faraday's, Oersted--Ampere's, and the Lorentz-force law. Thus a unification of the electromagnetism is achieved. Since the new model is frame indifferent, it is truly covariant in the sense that the governing system is invariant when changing to a coordinate frame that can accelerate or even deform in time.

  13. Comparison between covariant and orthogonal Lyapunov vectors.

    Science.gov (United States)

    Yang, Hong-liu; Radons, Günter

    2010-10-01

    Two sets of vectors, covariant Lyapunov vectors (CLVs) and orthogonal Lyapunov vectors (OLVs), are currently used to characterize the linear stability of chaotic systems. A comparison is made to show their similarity and difference, especially with respect to the influence on hydrodynamic Lyapunov modes (HLMs). Our numerical simulations show that in both Hamiltonian and dissipative systems HLMs formerly detected via OLVs survive if CLVs are used instead. Moreover, the previous classification of two universality classes works for CLVs as well, i.e., the dispersion relation is linear for Hamiltonian systems and quadratic for dissipative systems, respectively. The significance of HLMs changes in different ways for Hamiltonian and dissipative systems with the replacement of OLVs with CLVs. For general dissipative systems with nonhyperbolic dynamics the long-wavelength structure in Lyapunov vectors corresponding to near-zero Lyapunov exponents is strongly reduced if CLVs are used instead, whereas for highly hyperbolic dissipative systems the significance of HLMs is nearly identical for CLVs and OLVs. In contrast the HLM significance of Hamiltonian systems is always comparable for CLVs and OLVs irrespective of hyperbolicity. We also find that in Hamiltonian systems different symmetry relations between conjugate pairs are observed for CLVs and OLVs. Especially, CLVs in a conjugate pair are statistically indistinguishable in consequence of the microreversibility of Hamiltonian systems. Transformation properties of Lyapunov exponents, CLVs, and hyperbolicity under changes of coordinate are discussed in appendices.

  14. IMPROVED COVARIANCE DRIVEN BLIND SUBSPACE IDENTIFICATION METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhiyi; FAN Jiangling; HUA Hongxing

    2006-01-01

    An improved covariance driven subspace identification method is presented to identify the weakly excited modes. In this method, the traditional Hankel matrix is replaced by a reformed one to enhance the identifiability of weak characteristics. The robustness of eigenparameter estimation to noise contamination is reinforced by the improved Hankel matrix. In combination with component energy index (CEI) which indicates the vibration intensity of signal components, an alternative stabilization diagram is adopted to effectively separate spurious and physical modes. Simulation of a vibration system of multiple-degree-of-freedom and experiment of a frame structure subject to wind excitation are presented to demonstrate the improvement of the proposed blind method. The performance of this blind method is assessed in terms of its capability in extracting the weak modes as well as the accuracy of estimated parameters. The results have shown that the proposed blind method gives a better estimation of the weak modes from response signals of small signal to noise ratio (SNR)and gives a reliable separation of spurious and physical estimates.

  15. Perú-Chile: imágenes mutuas (Perú-Chile: mutual images

    Directory of Open Access Journals (Sweden)

    Álvaro González Riesle

    2014-06-01

    Full Text Available RESUMEN: A partir de los enfoques sobe Expansionismo-Revanchismo de Elizondo y las Imágenes en Espejo de Scott, se analizaron los contenidos de blogs referentes a imágenes mutuas entre Perú y Chile, comprendidos a partir de la fecha (16-01-2008 de presentación por parte del Perú de la Demanda ante el Tribunal de la Haya para la solución del Diferendo Limítrofe con Chile, hasta el 30-03-2011. Se han registrado intensas y variadas manifestaciones de hostilidad mutua, que respaldan la vigencia de la dinámica Expansionismo-Revanchismo en las imágenes mutuas entre Chile y Perú en los blogs analizados. Paralelamente, se detectaron contenidos correspondientes a actitudes integracionistas entre ambos países. Los resultados fundamentan la utilidad del enfoque de las Imágenes en Espejo como instrumento para el análisis de contenido de blogs portadores de mensajes de hostilidad e integración entre ambos países. Se propone una estrategia psicosocial binacional para desactivar la dinámica Expansionismo- revanchismo que contribuiría a producir catastróficas consecuencias para las generaciones actuales y futuras de ambos países; y, promover la integración fronteriza entre Tacna (Perú y Arica (Chile. ABSTRACT: The contents of blogs relating to mutual images between Peru and Chile were analyzed from the approaches about Expansionism – Revanchism of Elizondo, and The images on the mirror of Scott, included the date of the presentation (January 16th, 2008 by Peru of the demand before the International Court of Justice at the Hague for the solution of the border dispute with Chile until March 30th, 2011. There have been intense and varied manifestations of mutual hostility that support the validity of Expansionism-Revanchism dynamics in the mutual images between Chile and Peru in the analyzed blogs. At the same time, it was detected content corresponding to integrationist attitudes between the two countries. The results underlie the utility

  16. Schwinger mechanism in linear covariant gauges

    Science.gov (United States)

    Aguilar, A. C.; Binosi, D.; Papavassiliou, J.

    2017-02-01

    In this work we explore the applicability of a special gluon mass generating mechanism in the context of the linear covariant gauges. In particular, the implementation of the Schwinger mechanism in pure Yang-Mills theories hinges crucially on the inclusion of massless bound-state excitations in the fundamental nonperturbative vertices of the theory. The dynamical formation of such excitations is controlled by a homogeneous linear Bethe-Salpeter equation, whose nontrivial solutions have been studied only in the Landau gauge. Here, the form of this integral equation is derived for general values of the gauge-fixing parameter, under a number of simplifying assumptions that reduce the degree of technical complexity. The kernel of this equation consists of fully dressed gluon propagators, for which recent lattice data are used as input, and of three-gluon vertices dressed by a single form factor, which is modeled by means of certain physically motivated Ansätze. The gauge-dependent terms contributing to this kernel impose considerable restrictions on the infrared behavior of the vertex form factor; specifically, only infrared finite Ansätze are compatible with the existence of nontrivial solutions. When such Ansätze are employed, the numerical study of the integral equation reveals a continuity in the type of solutions as one varies the gauge-fixing parameter, indicating a smooth departure from the Landau gauge. Instead, the logarithmically divergent form factor displaying the characteristic "zero crossing," while perfectly consistent in the Landau gauge, has to undergo a dramatic qualitative transformation away from it, in order to yield acceptable solutions. The possible implications of these results are briefly discussed.

  17. Recurrence Analysis of Eddy Covariance Fluxes

    Science.gov (United States)

    Lange, Holger; Flach, Milan; Foken, Thomas; Hauhs, Michael

    2015-04-01

    The eddy covariance (EC) method is one key method to quantify fluxes in biogeochemical cycles in general, and carbon and energy transport across the vegetation-atmosphere boundary layer in particular. EC data from the worldwide net of flux towers (Fluxnet) have also been used to validate biogeochemical models. The high resolution data are usually obtained at 20 Hz sampling rate but are affected by missing values and other restrictions. In this contribution, we investigate the nonlinear dynamics of EC fluxes using Recurrence Analysis (RA). High resolution data from the site DE-Bay (Waldstein-Weidenbrunnen) and fluxes calculated at half-hourly resolution from eight locations (part of the La Thuile dataset) provide a set of very long time series to analyze. After careful quality assessment and Fluxnet standard gapfilling pretreatment, we calculate properties and indicators of the recurrent structure based both on Recurrence Plots as well as Recurrence Networks. Time series of RA measures obtained from windows moving along the time axis are presented. Their interpretation is guided by three different questions: (1) Is RA able to discern periods where the (atmospheric) conditions are particularly suitable to obtain reliable EC fluxes? (2) Is RA capable to detect dynamical transitions (different behavior) beyond those obvious from visual inspection? (3) Does RA contribute to an understanding of the nonlinear synchronization between EC fluxes and atmospheric parameters, which is crucial for both improving carbon flux models as well for reliable interpolation of gaps? (4) Is RA able to recommend an optimal time resolution for measuring EC data and for analyzing EC fluxes? (5) Is it possible to detect non-trivial periodicities with a global RA? We will demonstrate that the answers to all five questions is affirmative, and that RA provides insights into EC dynamics not easily obtained otherwise.

  18. Perturbative approach to covariance matrix of the matter power spectrum

    Science.gov (United States)

    Mohammed, Irshad; Seljak, Uroš; Vlah, Zvonimir

    2017-04-01

    We evaluate the covariance matrix of the matter power spectrum using perturbation theory up to dominant terms at 1-loop order and compare it to numerical simulations. We decompose the covariance matrix into the disconnected (Gaussian) part, trispectrum from the modes outside the survey (supersample variance) and trispectrum from the modes inside the survey, and show how the different components contribute to the overall covariance matrix. We find the agreement with the simulations is at a 10 per cent level up to k ∼ 1 h Mpc-1. We show that all the connected components are dominated by the large-scale modes (k methods to the covariance matrix. We perform an eigenmode decomposition of the connected part of the covariance matrix, showing that at higher k, it is dominated by a single eigenmode. The full covariance matrix can be approximated as the disconnected part only, with the connected part being treated as an external nuisance parameter with a known scale dependence, and a known prior on its variance for a given survey volume. Finally, we provide a prescription for how to evaluate the covariance matrix from small box simulations without the need to simulate large volumes.

  19. Quantification of Covariance in Tropical Cyclone Activity across Teleconnected Basins

    Science.gov (United States)

    Tolwinski-Ward, S. E.; Wang, D.

    2015-12-01

    Rigorous statistical quantification of natural hazard covariance across regions has important implications for risk management, and is also of fundamental scientific interest. We present a multivariate Bayesian Poisson regression model for inferring the covariance in tropical cyclone (TC) counts across multiple ocean basins and across Saffir-Simpson intensity categories. Such covariability results from the influence of large-scale modes of climate variability on local environments that can alternately suppress or enhance TC genesis and intensification, and our model also simultaneously quantifies the covariance of TC counts with various climatic modes in order to deduce the source of inter-basin TC covariability. The model explicitly treats the time-dependent uncertainty in observed maximum sustained wind data, and hence the nominal intensity category of each TC. Differences in annual TC counts as measured by different agencies are also formally addressed. The probabilistic output of the model can be probed for probabilistic answers to such questions as: - Does the relationship between different categories of TCs differ statistically by basin? - Which climatic predictors have significant relationships with TC activity in each basin? - Are the relationships between counts in different basins conditionally independent given the climatic predictors, or are there other factors at play affecting inter-basin covariability? - How can a portfolio of insured property be optimized across space to minimize risk? Although we present results of our model applied to TCs, the framework is generalizable to covariance estimation between multivariate counts of natural hazards across regions and/or across peril types.

  20. Generalized linear models with coarsened covariates: a practical Bayesian approach.

    Science.gov (United States)

    Johnson, Timothy R; Wiest, Michelle M

    2014-06-01

    Coarsened covariates are a common and sometimes unavoidable phenomenon encountered in statistical modeling. Covariates are coarsened when their values or categories have been grouped. This may be done to protect privacy or to simplify data collection or analysis when researchers are not aware of their drawbacks. Analyses with coarsened covariates based on ad hoc methods can compromise the validity of inferences. One valid method for accounting for a coarsened covariate is to use a marginal likelihood derived by summing or integrating over the unknown realizations of the covariate. However, algorithms for estimation based on this approach can be tedious to program and can be computationally expensive. These are significant obstacles to their use in practice. To overcome these limitations, we show that when expressed as a Bayesian probability model, a generalized linear model with a coarsened covariate can be posed as a tractable missing data problem where the missing data are due to censoring. We also show that this model is amenable to widely available general-purpose software for simulation-based inference for Bayesian probability models, providing researchers a very practical approach for dealing with coarsened covariates.

  1. Presencia de Hippidion y Equus (Amerhippus (Mammalia, Perissodactyla y su distribución en el Pleistoceno superior de Chile

    Directory of Open Access Journals (Sweden)

    Frassinetti, D.

    2000-12-01

    Full Text Available Fossil remains belonging to Equidae fram Chilean localities are described and taxonomically determined. Equus (Amerhippus and Hippidion species are identified; its geographic distribution in Chile and relations with others South American Equidae are given; a Late Pleistocene age is regarded for them. Stratigraphic and paleoecological considerations are also included.Se describen y sitúan taxonómicamente los restos de équidos de las localidades chilenas. Se identifican distintas especies de Equus (Amerhippus e Hippidion, señalando su distribución geográfica y relaciones con otros équidos sudamericanos, además de referirlos al Pleistoceno superior. Se analiza su situación estratigráfica así como consideraciones de tipo paleoecológico.

  2. Does taxonomic diversity in indicator groups influence their effectiveness in identifying priority areas for species conservation?

    DEFF Research Database (Denmark)

    Bladt, Jesper Stentoft; Larsen, Frank Wugt; Rahbek, Carsten

    2008-01-01

    the taxonomic diversity in species indicator groups influence their effectiveness in the identification of priority areas for species conservation. We tested whether indicator groups comprising a higher taxonomic diversity (i.e. indicator groups consisting of species from many different taxonomic groups...

  3. Bayes linear covariance matrix adjustment for multivariate dynamic linear models

    CERN Document Server

    Wilkinson, Darren J

    2008-01-01

    A methodology is developed for the adjustment of the covariance matrices underlying a multivariate constant time series dynamic linear model. The covariance matrices are embedded in a distribution-free inner-product space of matrix objects which facilitates such adjustment. This approach helps to make the analysis simple, tractable and robust. To illustrate the methods, a simple model is developed for a time series representing sales of certain brands of a product from a cash-and-carry depot. The covariance structure underlying the model is revised, and the benefits of this revision on first order inferences are then examined.

  4. Reality conditions for Ashtekar gravity from Lorentz-covariant formulation

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrov, Sergei [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Postbus 80.195, 3508 TD Utrecht (Netherlands)

    2006-03-21

    We study the limit of the Lorentz-covariant canonical formulation where the Immirzi parameter approaches {beta} = i. We show that, formulated in terms of a shifted spacetime connection, which also plays a crucial role in the covariant quantization, the limit is smooth and reproduces the canonical structure of the self-dual Ashtekar gravity. The reality conditions of Ashtekar gravity can be incorporated by means of the Dirac brackets derived from the covariant formulation and defined on an extended phase space which involves, besides the self-dual variables, also their anti-self-dual counterparts.

  5. Poincaré covariance of relativistic quantum position

    CERN Document Server

    Farkas, S; Weiner, M D; Farkas, Sz.

    2002-01-01

    A great number of problems of relativistic position in quantum mechanics are due to the use of coordinates which are not inherent objects of spacetime, cause unnecessary complications and can lead to misconceptions. We apply a coordinate-free approach to rule out such problems. Thus it will be clear, for example, that the Lorentz covariance of position, required usually on the analogy of Lorentz covariance of spacetime coordinates, is not well posed and we show that in a right setting the Newton--Wigner position is Poincar\\'e covariant, in contradiction with the usual assertions.

  6. Covariate-adjusted measures of discrimination for survival data

    DEFF Research Database (Denmark)

    White, Ian R; Rapsomaniki, Eleni; Frikke-Schmidt, Ruth

    2015-01-01

    MOTIVATION: Discrimination statistics describe the ability of a survival model to assign higher risks to individuals who experience earlier events: examples are Harrell's C-index and Royston and Sauerbrei's D, which we call the D-index. Prognostic covariates whose distributions are controlled...... by the study design (e.g. age and sex) influence discrimination and can make it difficult to compare model discrimination between studies. Although covariate adjustment is a standard procedure for quantifying disease-risk factor associations, there are no covariate adjustment methods for discrimination...

  7. Quantifying the taxonomic diversity in real species communities

    CERN Document Server

    Cartozo, C Caretta; Ricotta, C; Barthelemy, M; Caldarelli, G

    2008-01-01

    We analyze several florae (collections of plant species populating specific areas) in different geographic and climatic regions. For every list of species we produce a taxonomic classification tree and we consider its statistical properties. We find that regardless of the geographical location, the climate and the environment all species collections have universal statistical properties that we show to be also robust in time. We then compare observed data sets with simulated communities obtained by randomly sampling a large pool of species from all over the world. We find differences in the behavior of the statistical properties of the corresponding taxonomic trees. Our results suggest that it is possible to distinguish quantitatively real species assemblages from random collections and thus demonstrate the existence of correlations between species.

  8. Quantifying the taxonomic diversity in real species communities

    Energy Technology Data Exchange (ETDEWEB)

    Cartozo, Cecile Caretta [Laboratoire de Biophysique Statistique, ITP-FSB, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Garlaschelli, Diego [Department of Physics, University of Siena, Via Roma 56, 53100 Siena (Italy); Ricotta, Carlo [Department of Plant Biology, University of Rome ' La Sapienza' , Piazzale Aldo Moro 5, 00185 Rome (Italy); Barthelemy, Marc [School of Informatics and Biocomplexity Center, Indiana University, Eigenmann Hall, 1900 East Tenth Street, Bloomington, IN 47406 (United States); Caldarelli, Guido [INFM-CNR Centro SMC Department of Physics, University of Rome ' La Sapienza' , Piazzale Aldo Moro 5, 00185 Rome (Italy)], E-mail: cecile.carettacartozo@epfl.ch, E-mail: garlaschelli@unisi.it, E-mail: carlo.ricotta@uniroma1.it, E-mail: mbarthel@indiana.edu, E-mail: guido.caldarelli@roma1.infn.it

    2008-06-06

    We analyze several florae (collections of plant species populating specific areas) in different geographic and climatic regions. For every list of species we produce a taxonomic classification tree and we consider its statistical properties. We find that regardless of the geographical location, the climate and the environment all species collections have universal statistical properties that we show to be also robust in time. We then compare observed data sets with simulated communities obtained by randomly sampling a large pool of species from all over the world. We find differences in the behavior of the statistical properties of the corresponding taxonomic trees. Our results suggest that it is possible to distinguish quantitatively real species assemblages from random collections and thus demonstrate the existence of correlations between species.

  9. Chile: Una Vision Politica, Economica y Social (Chile: A Political, Economic, and Social View).

    Science.gov (United States)

    Cortes-Hwang, Adriana

    1972-01-01

    This address seeks to explain in brief the historical background and political, economic, and social conditions leading to the democratic election of a Marxist president in Chile. A historical sketch of Chilean government from independence in 1810 is provided with a description of the situation just before Salvador Allende's election in 1969. Some…

  10. Chile, Latin America, and the Asia-Pacific Region

    Directory of Open Access Journals (Sweden)

    Manfred Wilhelmy

    2005-01-01

    Full Text Available Text of a presentation in the Colloquium Chile and the World, organized by the Princeton University Program in Latin American Studies, May 6, 2005, in honor of Professor Paul E.Sigmund. The views expressed have not been reviewed or endorsed by the Chile Pacific Foundation. Manfred Wilhelmy holds a Ph.D. in Politics (1973 from Princeton University

  11. Critical Perspectives on Adolescent Vocational Guidance in Chile

    Science.gov (United States)

    McWhirter, Ellen Hawley; McWhirter, Benedict T.

    2012-01-01

    In this article, the lens of critical psychology is applied to adolescent career development and vocational guidance in Chile. The authors describe and critique the status of adolescent vocational guidance in Chile, the reproduction of extant social inequities in Chilean education, and offer recommendations for enhancing vocational guidance…

  12. Honors in Chile: New Engagements in the Higher Education System

    Science.gov (United States)

    Skewes, Juan Carlos; Sampaio, Carlos Alberto Cioce; Conway, Frederick J.

    2012-01-01

    Honors programs are rare in Latin America, and in Chile they were unknown before 2003. At the Universidad Austral de Chile, an interdisciplinary group of scholars linked to environmental studies put forward a pilot project for implementing a new experience in higher education. Challenged by an educational environment where (i) apathy and…

  13. Data on taxonomic status and phylogenetic relationship of tits

    Directory of Open Access Journals (Sweden)

    Xue-Juan Li

    2017-02-01

    Full Text Available The data in this paper are related to the research article entitled “Taxonomic status and phylogenetic relationship of tits based on mitogenomes and nuclear segments” (X.J. Li et al., 2016 [1]. The mitochondrial genomes and nuclear segments of tits were sequenced to analyze mitochondrial characteristics and phylogeny. In the data, the analyzed results are presented. The data holds the resulting files of mitochondrial characteristics, heterogeneity, best schemes, and trees.

  14. Data on taxonomic status and phylogenetic relationship of tits.

    Science.gov (United States)

    Li, Xue-Juan; Lin, Li-Liang; Cui, Ai-Ming; Bai, Jie; Wang, Xiao-Yang; Xin, Chao; Zhang, Zhen; Yang, Chao; Gao, Rui-Rui; Huang, Yuan; Lei, Fu-Min

    2017-02-01

    The data in this paper are related to the research article entitled "Taxonomic status and phylogenetic relationship of tits based on mitogenomes and nuclear segments" (X.J. Li et al., 2016) [1]. The mitochondrial genomes and nuclear segments of tits were sequenced to analyze mitochondrial characteristics and phylogeny. In the data, the analyzed results are presented. The data holds the resulting files of mitochondrial characteristics, heterogeneity, best schemes, and trees.

  15. Insights from Zootaxa on potential trends in zoological taxonomic activity

    Directory of Open Access Journals (Sweden)

    Dubois Alain

    2011-03-01

    Full Text Available Abstract Background An opinion currently shared by taxonomists and non taxonomists alike is that the work of inventorying biodiversity is unbalanced: firstly, in favour of countries in which taxonomy has been studied for a long time, and, secondly, in favour of vertebrates. In the current context of threats of species extinction, access for taxonomists to biological material and information becomes crucial if the scientific community really aims at a better knowledge of biological diversity before it is severely and irreversibly impoverished. We performed an analysis of 748 papers published in Zootaxa in 2006 and 2007, as well as 434 questionnaires sent to their authors to test these opinions. A generalization of these results to zoological taxonomy as a whole is discussed. Discussion We found that the disequilibrium is not exactly what it usually considered to be. The USA, China and Brazil are currently the three leading countries in zoological taxonomy. Each of them presents, however, a different pattern. Taxonomists from Asia and South America are younger and mainly work in universities, not museums. A bias in favour of vertebrates still exists if we refer to the effort invested in each group to produce taxonomic data, but not to the number of papers. Finally, we insist on the idea that "describing a species" is very different from "knowing a species". Summary The taxonomic involvement of a country, in terms of manpower and funding, appears to be a key factor in the development of fruitful taxonomic research. This message seems to have been understood by the countries that recently decided to increase considerably their taxonomic involvement. It still has to be received by those who did not.

  16. Taxonomic notes on Amblycerus Thunberg, 1815 (Coleoptera: Bruchidae)

    OpenAIRE

    Kingsolver, John M.; Cibele S. Ribeiro-Costa

    2011-01-01

    The following changes in nomenclature of some species of Amblyeems Thunberg, 1815, are proposed: A) Elevated to new taxonomic status- A. insuturatus (pic, 1902) from (Spennophagus subflavidus var.insuturatus); A. luteolineatus (pic, 1929) from (Spennophagus luteonotatus var .luteolineatus);A. paulonotatus (pic, 1906) from (Spennophagus luteonotatus var.paulonotatus). B) New synonymy-A. dispar(Sharp, 1885)(=Spermophagus longissimus Pic, 1902; =S. earyoborifonnis Pic, 1910; =S. guyanensis Pic, ...

  17. Covariance of metabolic and hemostatic risk indicators in men and women

    NARCIS (Netherlands)

    Riese, H; Vrijkotte, TGM; Meijer, P; Kluft, C; de Geus, Eco J.

    2001-01-01

    Background and objective: Multivariate analyses on clusters of metabolic and hemostatic risk indicators implicitly assume good test-retest reliability of these variables, substantial covariance among the various indicators, stability of covariance structure over time, and comparable covariance struc

  18. China and Chile Are to Be Free-Trade Partners

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ In line with the words "We hope that Chile's Next Partner is China", Chile is believed to choose China as the new negotiation party of Free Trade Agreements after signing respectively free trade agreements with Canada, the United States, EU and ROK. On January 24, Chile's trade delegation composed of 20 members led by Kaiross Feirch, the Head of economy general department of the Ministry of Foreign Affairs paid the first visit to China to launch first five-day round of mutual trade negotiation.Kaiross Feirch, the Head of economy general department of the Ministry of Foreign Affairs of Chile and Barbirlo Kafuleirla, Chile's Ambassador to China received special visit of reporters about this round.

  19. Marine Biodiversity in Juan Fernandez and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Directory of Open Access Journals (Sweden)

    Alan M Friedlander

    Full Text Available The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA, in Desventuradas, the laminarian kelp (Eisenia cokeri, which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC, in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  20. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Science.gov (United States)

    Friedlander, Alan M; Ballesteros, Enric; Caselle, Jennifer E; Gaymer, Carlos F; Palma, Alvaro T; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

    2016-01-01

    The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  1. Surface composition and taxonomic classification of a group of near-Earth and Mars-crossing asteroids

    CERN Document Server

    Sanchez, Juan A; Reddy, Vishnu; Nathues, Andreas

    2013-01-01

    In the past, constraining the surface composition of near-Earth asteroids (NEAs) has been difficult due to the lack of high quality near-IR spectral data (0.7-2.5 microns) that contain mineralogically diagnostic absorption bands. Here we present visible (0.43-0.95 microns) and near-infrared (0.7-2.5 microns) spectra of nine NEAs and five Mars-crossing asteroids (MCs). The studied NEAs are: 4055 Magellan, 19764 (2000 NF5), 89830 (2002 CE), 138404 (2000 HA24), 143381 (2003 BC21), 159609 (2002 AQ3), 164121 (2003 YT1), 241662 (2000 KO44) and 2007 ML13. The studied MCs are: 1656 Suomi, 2577 Litva, 5407 (1992 AX), 22449 Ottijeff and 47035 (1998 WS). The observations were conducted with the NTT at La Silla, Chile, the 2.2 m telescope at Calar Alto, Spain, and the IRTF on Mauna Kea, Hawai'i. The taxonomic classification (Bus system) of asteroids showed that all observed MC asteroids belong to the S-complex, including the S, Sr and Sl classes. Seven of the NEAs belong to the S-complex, including the S, Sa, Sk and Sl c...

  2. Differences in sperm ultrastructure between Mytilus chilensis and Mytilus galloprovincialis (Bivalvia, Mytilidae: could be used as a taxonomic trait?

    Directory of Open Access Journals (Sweden)

    Pablo A Oyarzún

    2014-03-01

    Full Text Available The sperm ultrastructure has been used to solve several systematic and phylogenetic problems in marine invertebrates. The sperm ultrastructure of the Chilean mussel Mytilus chilensis and Mytilus galloprovincialis corresponds to the ect-aquasperm type. Sperm from both taxa measured 55-60 μm between head (acrosome + nucleus, midpiece (only 5 mitochondria and the flagellum which in its end piece has a smaller diameter tail. The differences between both taxa are clearly shown, in the structure of the acrosome and nucleus. Therefore, according to our results and those reported in the literature, we indicate that Chilean native mussel sperm is different from other species of the Mytilus complex (M. trossulus, M. galloprovincialis and M. edulis. These differences in sperm ultrastructure found in M. chilensis, are another trait that can be used to validate the taxonomic status of the species. Differences in sperm morphology are related with reproductive isolation, and probably will be useful to understand future data on speciation. Finally, we discussed the finding that Mytilus galloprovincialis sperm from Chile have an acrosome notoriously smaller than those reported for specimens from Europe and Africa, though they have a great similarity with specimens from Japan, as reported in the literature.

  3. La atencion preescolar en Chile: desafios para la redemocratizacion (Preschool Care in Chile: Challenges for Redemocratization. Discussion Paper No. 13).

    Science.gov (United States)

    Filp, Johanna; Undurrage, Consuelo

    This paper examines the current status of programs for preschool children in Chile. Section 1 of the paper provides an overview of the situation of preschool children in Chile. The country's population includes more than 1.6 million children between the ages of 0 and 5 years 11 months, and in urban areas, 18.4 percent of children between the ages…

  4. Estudio del campo ocupacional del traductor en Santiago de Chile (A Study of Opportunities for Professional Translators in Santiago, Chile).

    Science.gov (United States)

    Cabrera, Ileana; And Others

    A study of translation as a profession in Chile covered two areas: a diagnostic study of the real need for literary, scientific, and technical translations, and a followup study of graduates of the translation degree program at the Catholic Pontifical University of Chile (Santiago). The analysis considered the relationship between the need for…

  5. The bispectrum covariance beyond Gaussianity: A log-normal approach

    CERN Document Server

    Martin, Sandra; Simon, Patrick

    2011-01-01

    To investigate and specify the statistical properties of cosmological fields with particular attention to possible non-Gaussian features, accurate formulae for the bispectrum and the bispectrum covariance are required. The bispectrum is the lowest-order statistic providing an estimate for non-Gaussianities of a distribution, and the bispectrum covariance depicts the errors of the bispectrum measurement and their correlation on different scales. Currently, there do exist fitting formulae for the bispectrum and an analytical expression for the bispectrum covariance, but the former is not very accurate and the latter contains several intricate terms and only one of them can be readily evaluated from the power spectrum of the studied field. Neglecting all higher-order terms results in the Gaussian approximation of the bispectrum covariance. We study the range of validity of this Gaussian approximation for two-dimensional non-Gaussian random fields. For this purpose, we simulate Gaussian and non-Gaussian random fi...

  6. AFCI-2.0 Neutron Cross Section Covariance Library

    Energy Technology Data Exchange (ETDEWEB)

    Herman, M.; Herman, M; Oblozinsky, P.; Mattoon, C.M.; Pigni, M.; Hoblit, S.; Mughabghab, S.F.; Sonzogni, A.; Talou, P.; Chadwick, M.B.; Hale, G.M.; Kahler, A.C.; Kawano, T.; Little, R.C.; Yount, P.G.

    2011-03-01

    The cross section covariance library has been under development by BNL-LANL collaborative effort over the last three years. The project builds on two covariance libraries developed earlier, with considerable input from BNL and LANL. In 2006, international effort under WPEC Subgroup 26 produced BOLNA covariance library by putting together data, often preliminary, from various sources for most important materials for nuclear reactor technology. This was followed in 2007 by collaborative effort of four US national laboratories to produce covariances, often of modest quality - hence the name low-fidelity, for virtually complete set of materials included in ENDF/B-VII.0. The present project is focusing on covariances of 4-5 major reaction channels for 110 materials of importance for power reactors. The work started under Global Nuclear Energy Partnership (GNEP) in 2008, which changed to Advanced Fuel Cycle Initiative (AFCI) in 2009. With the 2011 release the name has changed to the Covariance Multigroup Matrix for Advanced Reactor Applications (COMMARA) version 2.0. The primary purpose of the library is to provide covariances for AFCI data adjustment project, which is focusing on the needs of fast advanced burner reactors. Responsibility of BNL was defined as developing covariances for structural materials and fission products, management of the library and coordination of the work; LANL responsibility was defined as covariances for light nuclei and actinides. The COMMARA-2.0 covariance library has been developed by BNL-LANL collaboration for Advanced Fuel Cycle Initiative applications over the period of three years, 2008-2010. It contains covariances for 110 materials relevant to fast reactor R&D. The library is to be used together with the ENDF/B-VII.0 central values of the latest official release of US files of evaluated neutron cross sections. COMMARA-2.0 library contains neutron cross section covariances for 12 light nuclei (coolants and moderators), 78 structural

  7. Group Lasso estimation of high-dimensional covariance matrices

    CERN Document Server

    Bigot, Jérémie; Loubes, Jean-Michel; Alvarez, Lilian Muniz

    2010-01-01

    In this paper, we consider the Group Lasso estimator of the covariance matrix of a stochastic process corrupted by an additive noise. We propose to estimate the covariance matrix in a high-dimensional setting under the assumption that the process has a sparse representation in a large dictionary of basis functions. Using a matrix regression model, we propose a new methodology for high-dimensional covariance matrix estimation based on empirical contrast regularization by a group Lasso penalty. Using such a penalty, the method selects a sparse set of basis functions in the dictionary used to approximate the process, leading to an approximation of the covariance matrix into a low dimensional space. Consistency of the estimator is studied in Frobenius and operator norms and an application to sparse PCA is proposed.

  8. Progress of Covariance Evaluation at the China Nuclear Data Center

    Energy Technology Data Exchange (ETDEWEB)

    Xu, R., E-mail: xuruirui@ciae.ac.cn [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Zhang, Q. [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Shanxi Normal University, Linfen, Shanxi Province 041004 (China); Zhang, Y.; Liu, T.; Ge, Z.; Lu, H.; Sun, Z.; Yu, B. [China Nuclear Data Center, P.O. Box, 275(41), Beijing 102413 (China); Tang, G. [Peking University, Beijing 100871 (China)

    2015-01-15

    Covariance evaluations at the China Nuclear Data Center focus on the cross sections of structural materials and actinides in the fast neutron energy range. In addition to the well-known Least-squares approach, a method based on the analysis of the sources of experimental uncertainties is especially introduced to generate a covariance matrix for a particular reaction for which multiple measurements are available. The scheme of the covariance evaluation flow is presented, and an example of n+{sup 90}Zr is given to illuminate the whole procedure. It is proven that the accuracy of measurements can be properly incorporated into the covariance and the long-standing small uncertainty problem can be avoided.

  9. Electron localization functions and local measures of the covariance

    Indian Academy of Sciences (India)

    Paul W Ayers

    2005-09-01

    The electron localization measure proposed by Becke and Edgecombe is shown to be related to the covariance of the electron pair distribution. Just as with the electron localization function, the local covariance does not seem to be, in and of itself, a useful quantity for elucidating shell structure. A function of the local covariance, however, is useful for this purpose. A different function, based on the hyperbolic tangent, is proposed to elucidate the shell structure encapsulated by the local covariance; this function also seems to work better for the electron localization measure of Becke and Edgecombe. In addition, we propose a different measure for the electron localization that incorporates both the electron localization measure of Becke and Edgecombe and the Laplacian of the electron density; preliminary indications are that this measure is especially good at elucidating the shell structure in valence regions. Methods for evaluating electron localization functions directly from the electron density, without recourse to the Kohn-Sham orbitals, are discussed.

  10. Lorentz Covariant Canonical Symplectic Algorithms for Dynamics of Charged Particles

    CERN Document Server

    Wang, Yulei; Qin, Hong

    2016-01-01

    In this paper, the Lorentz covariance of algorithms is introduced. Under Lorentz transformation, both the form and performance of a Lorentz covariant algorithm are invariant. To acquire the advantages of symplectic algorithms and Lorentz covariance, a general procedure for constructing Lorentz covariant canonical symplectic algorithms (LCCSA) is provided, based on which an explicit LCCSA for dynamics of relativistic charged particles is built. LCCSA possesses Lorentz invariance as well as long-term numerical accuracy and stability, due to the preservation of discrete symplectic structure and Lorentz symmetry of the system. For situations with time-dependent electromagnetic fields, which is difficult to handle in traditional construction procedures of symplectic algorithms, LCCSA provides a perfect explicit canonical symplectic solution by implementing the discretization in 4-spacetime. We also show that LCCSA has built-in energy-based adaptive time steps, which can optimize the computation performance when th...

  11. Trouble shooting for covariance fitting in highly correlated data

    CERN Document Server

    Yoon, Boram; Lee, Weonjong; Jung, Chulwoo

    2011-01-01

    We report a possible solution to the trouble that the covariance fitting fails when the data is highly correlated and the covariance matrix has small eigenvalues. As an example, we choose the data analysis of highly correlated $B_K$ data on the basis of the SU(2) staggered chiral perturbation theory. Basically, the essence of the problem is that we do not have an accurate fitting function so that we cannot fit the highly correlated and precise data. When some eigenvalues of the covariance matrix are small, even a tiny error of fitting function can produce large chi-square and spoil the fitting procedure. We have applied a number of prescriptions available in the market such as diagonal approximation and cutoff method. In addition, we present a new method, the eigenmode shift method which fine-tunes the fitting function while keeping the covariance matrix untouched.

  12. Covariance fitting of highly correlated $B_K$ data

    CERN Document Server

    Yoon, Boram; Jung, Chulwoo; Lee, Weonjong

    2011-01-01

    We present the reason why we use the diagonal approximation (uncorrelated fitting) when we perform the data analysis of highly correlated $B_K$ data on the basis of the SU(2) staggered chiral perturbation theory. Basically, the essence of the problem is that we do not have enough statistics to determine the small eigenvalues of the covariance matrix with a high precision. As a result, we have the smallest eigenvalue, which is smaller than the statistical error of the covariance matrix, corresponding to an unphysical eigenmode. We have applied a number of prescriptions available in the market such as the cutoff method and modified covariance matrix method. It turns out that the cutoff method is not a good prescription and the modified covariance matrix method is an even worse one. The diagonal approximation turns out to be a good prescription if the data points are somehow correlated and the statistics are relatively poor.

  13. The Death of Socialism in Chile

    Science.gov (United States)

    1992-06-05

    him to return. During his absence Chile was ruled by a junta lead by General Carlos Ibanez del Campo . Welcomed back in March 1925, Alessandri kept...dictatorship of Colonel (later General) Carlos Ibanez del Campo in 1931-32. The first two were the product of divisions within the political community; the last...the Investigaciones detachment, and tanks were lined up in front of the palace. At 1:30 P.M. shortly after the Air Force bombed the presidential palace

  14. Pobreza Multidimensional en Chile: 1990-2009

    OpenAIRE

    Claudia Sanhueza; Angela Denis; Francisca Gallegos

    2010-01-01

    Este trabajo presenta una propuesta de medición multidimensional de la pobreza para Chile. Siguiendo el enfoque conceptual de Amartya Sen, pobreza no es meramente insuficiencia de ingresos, sino se define como privación de capacidades para la realización de funcionamientos valiosos en la vida. Medimos carencias individuales en tres grupos de la población: niños, población económicamente activa y adultos mayores, y en cinco dimensiones: educación, salud, vivienda, empleo e ingresos. La justifi...

  15. EFECTOS DEL EMBARAZO ADOLESCENTE EN CHILE

    OpenAIRE

    LOYOLA HEUFEMANN, AMANDA

    2014-01-01

    Los efectos del embarazo adolescente en Chile han sido poco estudiados aun cuando existe diversa literatura para el resto del mundo, en especial para países desarrollados. Este trabajo estima el efecto del embarazo adolescente sobre la asistencia o completitud de la educación secundaria, años de escolaridad y participación laboral. Usando datos de corte transversal del a˜no 2012 y un enfoque de variable instrumental a trav´es del uso de la entrega comunal de la píldora anticoncept...

  16. Recent IBA setup improvements in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, P.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile)]. E-mail: pmiranda@fisica.ciencias.uchile.cl; Chesta, M.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Cancino, S.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Morales, J.R. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Dinator, M.I. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Wachter, J.A. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Tenreiro, C. [Facultad de Ingenieria, Campus Curico, Universidad de Talca (Chile)

    2006-07-15

    This paper describes the main characteristics of the ion beam facility based on a 3.75 MeV Van de Graaff accelerator model KN3750 of HVE at University of Chile. Recent setup improvements on three beam lines available, one dedicated for PIXE analyzes, one designed for RBS-PESA analyzes and a multipurpose vacuum chamber, as well as beam energy calibration experiments of the accelerator will be summarized. Current research activities are focused on the application of the different IBA techniques for the material, biological and environmental analysis. In addition, nuclear activation analysis and the study of nuclear reactions of astrophysical interest has begun to be developed as basic research.

  17. The genus Callophyllis (Kallymeniaceae, Rhodophyta from the central-south Chilean coast (33° to 41° S, with the description of two new species El género Callophyllis (Kallymeniaceae, Rhodophyta de la costa central y sur de Chile (33° a 41° S, con la descripción de dos nuevas especies

    Directory of Open Access Journals (Sweden)

    NATALIA ARAKAKI

    2011-12-01

    Full Text Available The taxonomic status of the species in the genus Callophyllis Kützing (Kallymeniaceae, Rhodophyta from central-south Chile (33° to 41° S is examined on the basis of morphological and molecular evidence. Of the four species originally cited for central Chile, C. variegata, C. pinnata, C. atrosanguinea and C. laciniata, only the presence of C. variegata has been confirmed in this study. C. pinnata reported from Chile is found to be different from C. pinnata described from California, and it is here newly described as C. concepcionensis sp. nov. C. atrosanguinea from southern Chile (including C. linguata from the Antarctic Peninsula is distinct from the species called C. atrosanguinea from central-south Chile, the latter which is here described as C. macrostiolata sp. nov. C. variegata, C. concepcionensis and C. macrostiolata are distinguished from one another by their external habit, the nature and distribution of their cystocarps, and the female reproductive morphology. Comparative rbcL sequence analysis corroborates the distinction of these taxa from central-south Chile and their relationships to other species worldwide.Se examina el estatus taxonómico de las especies del género Callophyllis Kützing (Kallymeniaceae, Rhodophyta de la costa centro-sur de Chile (33° a 41° S en base a caracteres morfológicos y moleculares. De las cuatro especies citadas para Chile central, C. variegata, C. pinnata, C. atrosanguinea y C. laciniata, solo la presencia de C. variegata ha sido confirmada en este estudio. C. pinnata de Chile muestra diferencias con C. pinnata descrita para California y con el resto de las especies de Callophyllis hasta ahora conocidas, constituyendo así una nueva especie, C. concepcionensis sp. nov. C. atrosanguinea del sur de Chile (incluyendo C. linguata de la Península Antártica muestra diferencias con la especie llamada C. atrosanguinea de la costa centro-sur de Chile, esta última especie es descrita como C. macrostiolata

  18. Web Tool for Constructing a Covariance Matrix from EXFOR Uncertainties

    Directory of Open Access Journals (Sweden)

    Zerkin V.

    2012-05-01

    Full Text Available The experimental nuclear reaction database EXFOR contains almost no covariance data because most experimentalists provide experimental data only with uncertainties. With the tool described here a user can construct an experimental covariance matrix from uncertainties using general assumptions when uncertainty information given in EXFOR is poor (or even absent. The tool is publically available in the IAEA EXFOR Web retrieval system [1].

  19. Comparison of Methods for Handling Missing Covariate Data

    OpenAIRE

    Johansson, Åsa M.; Karlsson, Mats O

    2013-01-01

    Missing covariate data is a common problem in nonlinear mixed effects modelling of clinical data. The aim of this study was to implement and compare methods for handling missing covariate data in nonlinear mixed effects modelling under different missing data mechanisms. Simulations generated data for 200 individuals with a 50% difference in clearance between males and females. Three different types of missing data mechanisms were simulated and information about sex was missing for 50% of the ...

  20. A Generalized Autocovariance Least-Squares Method for Covariance Estimation

    DEFF Research Database (Denmark)

    Åkesson, Bernt Magnus; Jørgensen, John Bagterp; Poulsen, Niels Kjølstad;

    2007-01-01

    A generalization of the autocovariance least- squares method for estimating noise covariances is presented. The method can estimate mutually correlated system and sensor noise and can be used with both the predicting and the filtering form of the Kalman filter.......A generalization of the autocovariance least- squares method for estimating noise covariances is presented. The method can estimate mutually correlated system and sensor noise and can be used with both the predicting and the filtering form of the Kalman filter....

  1. High-dimensional covariance matrix estimation with missing observations

    OpenAIRE

    Lounici, Karim

    2014-01-01

    In this paper, we study the problem of high-dimensional covariance matrix estimation with missing observations. We propose a simple procedure computationally tractable in high-dimension and that does not require imputation of the missing data. We establish non-asymptotic sparsity oracle inequalities for the estimation of the covariance matrix involving the Frobenius and the spectral norms which are valid for any setting of the sample size, probability of a missing observation and the dimensio...

  2. Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence

    Science.gov (United States)

    Colihueque, Nelson; Gantz, Alberto; Rau, Jaime Ricardo; Parraguez, Margarita

    2015-01-01

    Abstract In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy. PMID:26668551

  3. Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence.

    Science.gov (United States)

    Colihueque, Nelson; Gantz, Alberto; Rau, Jaime Ricardo; Parraguez, Margarita

    2015-01-01

    In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy.

  4. 75 FR 10846 - The Chile Fund, Inc., et al.; Notice of Application

    Science.gov (United States)

    2010-03-09

    ... COMMISSION The Chile Fund, Inc., et al.; Notice of Application March 2, 2010. AGENCY: Securities and Exchange.... Applicants: The Chile Fund, Inc. (``Chile Fund''), Aberdeen Australia Equity Fund (``Australia Fund,'' together with the Chile Fund, the ``Current Funds''), Aberdeen Asset Management Asia Limited...

  5. Gaussian covariance matrices for anisotropic galaxy clustering measurements

    Science.gov (United States)

    Grieb, Jan Niklas; Sánchez, Ariel G.; Salazar-Albornoz, Salvador; Dalla Vecchia, Claudio

    2016-04-01

    Measurements of the redshift-space galaxy clustering have been a prolific source of cosmological information in recent years. Accurate covariance estimates are an essential step for the validation of galaxy clustering models of the redshift-space two-point statistics. Usually, only a limited set of accurate N-body simulations is available. Thus, assessing the data covariance is not possible or only leads to a noisy estimate. Further, relying on simulated realizations of the survey data means that tests of the cosmology dependence of the covariance are expensive. With these points in mind, this work presents a simple theoretical model for the linear covariance of anisotropic galaxy clustering observations with synthetic catalogues. Considering the Legendre moments (`multipoles') of the two-point statistics and projections into wide bins of the line-of-sight parameter (`clustering wedges'), we describe the modelling of the covariance for these anisotropic clustering measurements for galaxy samples with a trivial geometry in the case of a Gaussian approximation of the clustering likelihood. As main result of this paper, we give the explicit formulae for Fourier and configuration space covariance matrices. To validate our model, we create synthetic halo occupation distribution galaxy catalogues by populating the haloes of an ensemble of large-volume N-body simulations. Using linear and non-linear input power spectra, we find very good agreement between the model predictions and the measurements on the synthetic catalogues in the quasi-linear regime.

  6. Computational protein design quantifies structural constraints on amino acid covariation.

    Directory of Open Access Journals (Sweden)

    Noah Ollikainen

    Full Text Available Amino acid covariation, where the identities of amino acids at different sequence positions are correlated, is a hallmark of naturally occurring proteins. This covariation can arise from multiple factors, including selective pressures for maintaining protein structure, requirements imposed by a specific function, or from phylogenetic sampling bias. Here we employed flexible backbone computational protein design to quantify the extent to which protein structure has constrained amino acid covariation for 40 diverse protein domains. We find significant similarities between the amino acid covariation in alignments of natural protein sequences and sequences optimized for their structures by computational protein design methods. These results indicate that the structural constraints imposed by protein architecture play a dominant role in shaping amino acid covariation and that computational protein design methods can capture these effects. We also find that the similarity between natural and designed covariation is sensitive to the magnitude and mechanism of backbone flexibility used in computational protein design. Our results thus highlight the necessity of including backbone flexibility to correctly model precise details of correlated amino acid changes and give insights into the pressures underlying these correlations.

  7. Perturbative approach to covariance matrix of the matter power spectrum

    CERN Document Server

    Mohammed, Irshad; Vlah, Zvonimir

    2016-01-01

    We evaluate the covariance matrix of the matter power spectrum using perturbation theory up to dominant terms at 1-loop order and compare it to numerical simulations. We decompose the covariance matrix into the disconnected (Gaussian) part, trispectrum from the modes outside the survey (beat coupling or super-sample variance), and trispectrum from the modes inside the survey, and show how the different components contribute to the overall covariance matrix. We find the agreement with the simulations is at a 10\\% level up to $k \\sim 1 h {\\rm Mpc^{-1}}$. We show that all the connected components are dominated by the large-scale modes ($k<0.1 h {\\rm Mpc^{-1}}$), regardless of the value of the wavevectors $k,\\, k'$ of the covariance matrix, suggesting that one must be careful in applying the jackknife or bootstrap methods to the covariance matrix. We perform an eigenmode decomposition of the connected part of the covariance matrix, showing that at higher $k$ it is dominated by a single eigenmode. The full cova...

  8. The Performance Analysis Based on SAR Sample Covariance Matrix

    Directory of Open Access Journals (Sweden)

    Esra Erten

    2012-03-01

    Full Text Available Multi-channel systems appear in several fields of application in science. In the Synthetic Aperture Radar (SAR context, multi-channel systems may refer to different domains, as multi-polarization, multi-interferometric or multi-temporal data, or even a combination of them. Due to the inherent speckle phenomenon present in SAR images, the statistical description of the data is almost mandatory for its utilization. The complex images acquired over natural media present in general zero-mean circular Gaussian characteristics. In this case, second order statistics as the multi-channel covariance matrix fully describe the data. For practical situations however, the covariance matrix has to be estimated using a limited number of samples, and this sample covariance matrix follow the complex Wishart distribution. In this context, the eigendecomposition of the multi-channel covariance matrix has been shown in different areas of high relevance regarding the physical properties of the imaged scene. Specifically, the maximum eigenvalue of the covariance matrix has been frequently used in different applications as target or change detection, estimation of the dominant scattering mechanism in polarimetric data, moving target indication, etc. In this paper, the statistical behavior of the maximum eigenvalue derived from the eigendecomposition of the sample multi-channel covariance matrix in terms of multi-channel SAR images is simplified for SAR community. Validation is performed against simulated data and examples of estimation and detection problems using the analytical expressions are as well given.

  9. [Clinical research XIX. From clinical judgment to analysis of covariance].

    Science.gov (United States)

    Pérez-Rodríguez, Marcela; Palacios-Cruz, Lino; Moreno, Jorge; Rivas-Ruiz, Rodolfo; Talavera, Juan O

    2014-01-01

    The analysis of covariance (ANCOVA) is based on the general linear models. This technique involves a regression model, often multiple, in which the outcome is presented as a continuous variable, the independent variables are qualitative or are introduced into the model as dummy or dichotomous variables, and factors for which adjustment is required (covariates) can be in any measurement level (i.e. nominal, ordinal or continuous). The maneuvers can be entered into the model as 1) fixed effects, or 2) random effects. The difference between fixed effects and random effects depends on the type of information we want from the analysis of the effects. ANCOVA effect separates the independent variables from the effect of co-variables, i.e., corrects the dependent variable eliminating the influence of covariates, given that these variables change in conjunction with maneuvers or treatments, affecting the outcome variable. ANCOVA should be done only if it meets three assumptions: 1) the relationship between the covariate and the outcome is linear, 2) there is homogeneity of slopes, and 3) the covariate and the independent variable are independent from each other.

  10. Covariance fitting of highly-correlated data in lattice QCD

    Science.gov (United States)

    Yoon, Boram; Jang, Yong-Chull; Jung, Chulwoo; Lee, Weonjong

    2013-07-01

    We address a frequently-asked question on the covariance fitting of highly-correlated data such as our B K data based on the SU(2) staggered chiral perturbation theory. Basically, the essence of the problem is that we do not have a fitting function accurate enough to fit extremely precise data. When eigenvalues of the covariance matrix are small, even a tiny error in the fitting function yields a large chi-square value and spoils the fitting procedure. We have applied a number of prescriptions available in the market, such as the cut-off method, modified covariance matrix method, and Bayesian method. We also propose a brand new method, the eigenmode shift (ES) method, which allows a full covariance fitting without modifying the covariance matrix at all. We provide a pedagogical example of data analysis in which the cut-off method manifestly fails in fitting, but the rest work well. In our case of the B K fitting, the diagonal approximation, the cut-off method, the ES method, and the Bayesian method work reasonably well in an engineering sense. However, interpreting the meaning of χ 2 is easier in the case of the ES method and the Bayesian method in a theoretical sense aesthetically. Hence, the ES method can be a useful alternative optional tool to check the systematic error caused by the covariance fitting procedure.

  11. [Reflections about the historical development of biomedical sciences in Chile and the role of Revista Médica de Chile: an homage on 130-years old].

    Science.gov (United States)

    Vargas Fernández, Luis

    2002-12-01

    When Revista Médica de Chile turns to be 130 years old, the author reflects about the difficulties that scientific and technological creativity faces in Chile, considering that there was a 70 years gap between its historical origin in Chile compared to developed countries. The scientific progress erases the boundaries between Biomedicine and science and technology. This progress has resulted in an improvement in the quality of scientific publications in Revista Medica de Chile. The editorial work has also contributed to this improvement. Revista Medica de Chile has obtained international recognition and stands in a good position as a medical journal in Latin America and Chile.

  12. Silencio y memoria: Nocturno de Chile

    Directory of Open Access Journals (Sweden)

    Pedro Iniesta Ruiz

    2016-12-01

    Full Text Available El presente estudio, sostenido por el Trabajo de Fin de Grado Representación y ficción: Nocturno de Chile y Sostiene Pereira (2015, se introduce en la construcción literaria articulada en la obra Nocturno de Chile, de Roberto Bolaño, examinando y evaluando sus fronteras, fronteras que resultan tan movedizas como las de cualquier construcción inserta en el marco de la ficción. Las implicaciones históricas y políticas del relato hacen que su impronta testimonial cobre una fuerza inusitada, y nociones como la memoria, la violencia o el silencio ayudan a vertebrar una obra de arte verbal que logra, en el decurso de su propia narración, asediar al lector con las angustiosas imágenes de un pasado hecho presente en el camino de un tiempo político que se subyuga a la propia creación artística.

  13. [The Vida Chile program: results and challenges with health promotion policy in Chile, 1998-2006].

    Science.gov (United States)

    Salinas, Judith; Cancino, Anselmo; Pezoa, Sergio; Salamanca, Fernando; Soto, Marina

    2007-01-01

    The Government of Chile has placed a high priority on health promotion. This is evident in the advances made through its National Plan for Health Promotion (Plan Nacional de Promoción de la Salud) and the Vida Chile National Council for Health Promotion (Consejo Nacional para la Promoción de la Salud Vida Chile). Chaired by the minister of health, Vida Chile is made up of 28 public and private institutions from around the country. Vida Chile has a network of local councils that have been established in the country's comunas (communes, or local-level divisions of the country's provinces) and that include government officials and representatives of local societal and community organizations and private businesses. This report details the methods used to evaluate the National Plan as well as provides a preliminary assessment of the technical and financial results for the 1998-2006 period. Coverage indicators (number of participants; number of accredited health-promoting schools, workplaces, and universities; and number of health promotion events) and the extent of strategy implementation were used to measure the success of the program. Health promotion activities grew markedly during this period. Among the notable accomplishments were the following four: (1) 98% of the communes now have their own community health promotion plan and intersectoral Vida Chile committee to implement the plan, (2) there has been an increase in societal and community groups involved in the health promotion strategies, (3) 34% of the primary and secondary schools have become accredited health-promoting schools, and (4) approximately 20% of the total population benefited directly from community-health-plan activities in 2006. The average per capita cost of the community health plans' activities in 2006 was US$ 6.60. The two most important factors that facilitated the operation of the local health promotion plans were participation by community and societal groups and having an adequate

  14. ESO and Chile: 10 Years of Productive Scientific Collaboration

    Science.gov (United States)

    2006-06-01

    ESO and the Government of Chile launched today the book "10 Years Exploring the Universe", written by the beneficiaries of the ESO-Chile Joint Committee. This annual fund provides grants for individual Chilean scientists, research infrastructures, scientific congresses, workshops for science teachers and astronomy outreach programmes for the public. In a ceremony held in Santiago on 19 June 2006, the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) and the Chilean Ministry of Foreign Affairs marked the 10th Anniversary of the Supplementary Agreement, which granted to Chilean astronomers up to 10 percent of the total observing time on ESO telescopes. This agreement also established an annual fund for the development of astronomy, managed by the so-called "ESO-Chile Joint Committee". ESO PR Photo 21/06 ESO PR Photo 21/06 Ten Years ESO-Chile Agreement Ceremony The celebration event was hosted by ESO Director General, Dr. Catherine Cesarsky, and the Director of Special Policy for the Chilean Ministry of Foreign Affairs, Ambassador Luis Winter. "ESO's commitment is, and always will be, to promote astronomy and scientific knowledge in the country hosting our observatories", said ESO Director General, Dr. Catherine Cesarsky. "We hope Chile and Europe will continue with great achievements in this fascinating joint adventure, the exploration of the universe." On behalf of the Government of Chile, Ambassador Luis Winter outlined the historical importance of the Supplementary Agreement, ratified by the Chilean Congress in 1996. "Such is the magnitude of ESO-Chile Joint Committee that, only in 2005, this annual fund represented 8 percent of all financing sources for Chilean astronomy, including those from Government and universities", Ambassador Winter said. The ESO Representative and Head of Science in Chile, Dr. Felix Mirabel, and the appointed Chilean astronomer for the ESO-Chile Joint Committee, Dr. Leonardo Bronfman, also took part in the

  15. Species delimitation in taxonomically difficult fungi: the case of Hymenogaster.

    Directory of Open Access Journals (Sweden)

    Benjamin Stielow

    Full Text Available BACKGROUND: False truffles are ecologically important as mycorrhizal partners of trees and evolutionarily highly interesting as the result of a shift from epigeous mushroom-like to underground fruiting bodies. Since its first description by Vittadini in 1831, inappropriate species concepts in the highly diverse false truffle genus Hymenogaster has led to continued confusion, caused by a large variety of prevailing taxonomical opinions. METHODOLOGY: In this study, we reconsidered the species delimitations in Hymenogaster based on a comprehensive collection of Central European taxa comprising more than 140 fruiting bodies from 20 years of field work. The ITS rDNA sequence dataset was subjected to phylogenetic analysis as well as clustering optimization using OPTSIL software. CONCLUSIONS: Among distinct species concepts from the literature used to create reference partitions for clustering optimization, the broadest concept resulted in the highest agreement with the ITS data. Our results indicate a highly variable morphology of H. citrinus and H. griseus, most likely linked to environmental influences on the phenology (maturity, habitat, soil type and growing season. In particular, taxa described in the 19(th century frequently appear as conspecific. Conversely, H. niveus appears as species complex comprising seven cryptic species with almost identical macro- and micromorphology. H. intermedius and H. huthii are described as novel species, each of which with a distinct morphology intermediate between two species complexes. A revised taxonomy for one of the most taxonomically difficult genera of Basidiomycetes is proposed, including an updated identification key. The (semi-automated selection among species concepts used here is of importance for the revision of taxonomically problematic organism groups in general.

  16. Taxonomic and thematic organisation of proper name conceptual knowledge.

    Science.gov (United States)

    Crutch, Sebastian J; Warrington, Elizabeth K

    2011-01-01

    We report the investigation of the organisation of proper names in two aphasic patients (NBC and FBI). The performance of both patients on spoken word to written word matching tasks was inconsistent, affected by presentation rate and semantic relatedness of the competing responses, all hallmarks of a refractory semantic access dysphasia. In a series of experiments we explored the semantic relatedness effects within their proper name vocabulary, including brand names and person names. First we demonstrated the interaction between very fine grain organisation and personal experience, with one patient with a special interest in the cinema demonstrating higher error rates when identifying the names of actors working in a similar film genre (e.g., action movies: Arnold Schwarzenegger, Bruce Willis, Sylvester Stallone, Mel Gibson) than those working in different genres (e.g., Arnold Schwarzenegger, Gregory Peck, Robin Williams, Gene Kelly). Second we compared directly two potential principles of semantic organisation - taxonomic and thematic. Furthermore we considered these principles of organisation in the context of the individuals' personal knowledge base. We selected topics matching the interests and experience of each patient, namely cinema and literature (NBC) and naval history (FBI). The stimulus items were arranged in taxonomic arrays (e.g., Jane Austen, Emily Bronte, Agatha Christie), thematic arrays (e.g., Jane Austen, Pride and Prejudice, Mr Darcy), and unrelated arrays (e.g., Jane Austen, Wuthering Heights, Hercule Poirot). We documented that different patterns of taxonomic and thematic organisation were constrained by whether the individual has limited knowledge, moderate knowledge or detailed knowledge of a particular vocabulary. It is suggested that moderate proper name knowledge is primarily organised by taxonomy whereas extensive experience results in a more detailed knowledge base in which theme is a powerful organising principle.

  17. Taxonomic and Thematic Organisation of Proper Name Conceptual Knowledge

    Directory of Open Access Journals (Sweden)

    Sebastian J. Crutch

    2011-01-01

    Full Text Available We report the investigation of the organisation of proper names in two aphasic patients (NBC and FBI. The performance of both patients on spoken word to written word matching tasks was inconsistent, affected by presentation rate and semantic relatedness of the competing responses, all hallmarks of a refractory semantic access dysphasia. In a series of experiments we explored the semantic relatedness effects within their proper name vocabulary, including brand names and person names. First we demonstrated the interaction between very fine grain organisation and personal experience, with one patient with a special interest in the cinema demonstrating higher error rates when identifying the names of actors working in a similar film genre (e.g. action movies: Arnold Schwarzenegger, Bruce Willis, Sylvester Stallone, Mel Gibson than those working in different genres (e.g. Arnold Schwarzenegger, Gregory Peck, Robin Williams, Gene Kelly. Second we compared directly two potential principles of semantic organisation – taxonomic and thematic. Furthermore we considered these principles of organisation in the context of the individuals' personal knowledge base. We selected topics matching the interests and experience of each patient, namely cinema and literature (NBC and naval history (FBI. The stimulus items were arranged in taxonomic arrays (e.g. Jane Austen, Emily Bronte, Agatha Christie, thematic arrays (e.g. Jane Austen, Pride and Prejudice, Mr Darcy, and unrelated arrays (e.g. Jane Austen, Wuthering Heights, Hercule Poirot. We documented that different patterns of taxonomic and thematic organisation were constrained by whether the individual has limited knowledge, moderate knowledge or detailed knowledge of a particular vocabulary. It is suggested that moderate proper name knowledge is primarily organised by taxonomy whereas extensive experience results in a more detailed knowledge base in which theme is a powerful organising principle.

  18. Taxonomic information exchange and copyright: the Plazi approach

    Directory of Open Access Journals (Sweden)

    Egloff Willi

    2009-03-01

    Full Text Available Abstract Background A large part of our knowledge on the world's species is recorded in the corpus of biodiversity literature with well over hundred million pages, and is represented in natural history collections estimated at 2 – 3 billion specimens. But this body of knowledge is almost entirely in paper-print form and is not directly accessible through the Internet. For the digitization of this literature, new territories have to be chartered in the fields of technical, legal and social issues that presently impede its advance. The taxonomic literature seems especially destined for such a transformation. Discussion Plazi was founded as an association with the primary goal of transforming both the printed and, more recently, "born-digital" taxonomic literature into semantically enabled, enhanced documents. This includes the creation of a test body of literature, an XML schema modeling its logic content (TaxonX, the development of a mark-up editor (GoldenGATE allowing also the enhancement of documents with links to external resources via Life Science Identifiers (LSID, a repository for publications and issuance of bibliographic identifiers, a dedicated server to serve the marked up content (the Plazi Search and Retrieval Server, SRS and semantic tools to mine information. Plazi's workflow is designed to respect copyright protection and achieves extraction by observing exceptions and limitations existent in international copyright law. Conclusion The information found in Plazi's databases – taxonomic treatments as well as the metadata of the publications – are in the public domain and can therefore be used for further scientific research without any restriction, whether or not contained in copyrighted publications.

  19. Partial migration in fishes: definitions, methodologies and taxonomic distribution

    DEFF Research Database (Denmark)

    Chapman, B B; Skov, C; Hulthén, K

    2012-01-01

    published. In addition, previous work and synthesis has been hampered by a varied lexicon associated with this phenomenon in fishes. In this review, definitions and important concepts in partial migration research are discussed, and a classification system of the different forms of partial migration...... in fishes introduced. Next, a detailed taxonomic overview of partial migration in this group is considered. Finally, methodological approaches that ichthyologists can use to study this fascinating phenomenon are reviewed. Partial migration is more widespread amongst fishes than previously thought, and given...

  20. Susceptibility of Haemophilus aegyptius to trooleandomycin: lack of taxonomic value.

    Science.gov (United States)

    Martel, A Y; Sottnek, F O; Thomas, M L; Albritton, W L

    1986-04-01

    Two hundred and nine strains of Haemophilus influenzae and Haemophilus aegyptius were screened for trooleandomycin susceptibility. Four strains were shown to be sensitive to the drug. Of these four, two were Haemophilus aegyptius (ATCC 11116, NCTC 8134), and the other two were Haemophilus influenzae biotype I (1-605) and IV (80-212. One strain of Haemophilus aegyptius (NCTC 8135) was resistant to trooleandomycin. Restriction enzyme assays and DNA homology were carried out to establish relationships between the strains. It is concluded that trooleandomycin susceptibility has no taxonomic value to differentiate between Haemophilus aegyptius and biotype III Haemophilus influenzae.

  1. Taxonomic review of the Neotropical genus Neopachylus (Arachnida, Opiliones, Gonyleptidae

    Directory of Open Access Journals (Sweden)

    Vivian Moreira Montemor

    2015-03-01

    Full Text Available A taxonomic review of the genus Neopachylus Roewer, 1913 together with keys to the species for both males and females are presented. Gephyropachylus marginatus Mello-Leitão, 1931 is considered a junior subjective synonym of Neopachylus serrinha Soares & Soares, 1947, and Huralvius incertus Mello-Leitão, 1935 is considered a synonym of Neopachylus nebulosus (Mello-Leitão, 1936. This genus is restricted to southern Brazil, occurring in states of Paraná, Santa Catarina and Rio Grande do Sul.

  2. El Parque Portal Bicentenario en Santiago de Chile / Portal Bicentennial Park in Santiago de Chile

    Directory of Open Access Journals (Sweden)

    Beach Lobos, Myriam;

    2007-06-01

    Full Text Available Se presenta los principios que orientaron el diseño del Parque Portal Bicentenario, un parque de 50 hás. que será el eje principal de la nueva urbanización “Ciudad Parque Bicentenario”, actualmente en construcción en los terrenos del ex aeropuerto de Los Cerrillos en Santiago de Chile.The following text was submitted to the Architecture Competition together with the project drawings. It presents the principles that leaded the design. The 123 acres park will be the main axis of a new urban development in Santiago “Ciudad Parque Bicentenario” at present under construction on the area occupied by the former Cerrillos Airport, Santiago de Chile.

  3. An Empirical State Error Covariance Matrix for Batch State Estimation

    Science.gov (United States)

    Frisbee, Joseph H., Jr.

    2011-01-01

    State estimation techniques serve effectively to provide mean state estimates. However, the state error covariance matrices provided as part of these techniques suffer from some degree of lack of confidence in their ability to adequately describe the uncertainty in the estimated states. A specific problem with the traditional form of state error covariance matrices is that they represent only a mapping of the assumed observation error characteristics into the state space. Any errors that arise from other sources (environment modeling, precision, etc.) are not directly represented in a traditional, theoretical state error covariance matrix. Consider that an actual observation contains only measurement error and that an estimated observation contains all other errors, known and unknown. It then follows that a measurement residual (the difference between expected and observed measurements) contains all errors for that measurement. Therefore, a direct and appropriate inclusion of the actual measurement residuals in the state error covariance matrix will result in an empirical state error covariance matrix. This empirical state error covariance matrix will fully account for the error in the state estimate. By way of a literal reinterpretation of the equations involved in the weighted least squares estimation algorithm, it is possible to arrive at an appropriate, and formally correct, empirical state error covariance matrix. The first specific step of the method is to use the average form of the weighted measurement residual variance performance index rather than its usual total weighted residual form. Next it is helpful to interpret the solution to the normal equations as the average of a collection of sample vectors drawn from a hypothetical parent population. From here, using a standard statistical analysis approach, it directly follows as to how to determine the standard empirical state error covariance matrix. This matrix will contain the total uncertainty in the

  4. Covariate-adjusted confidence interval for the intraclass correlation coefficient.

    Science.gov (United States)

    Shoukri, Mohamed M; Donner, Allan; El-Dali, Abdelmoneim

    2013-09-01

    A crucial step in designing a new study is to estimate the required sample size. For a design involving cluster sampling, the appropriate sample size depends on the so-called design effect, which is a function of the average cluster size and the intracluster correlation coefficient (ICC). It is well-known that under the framework of hierarchical and generalized linear models, a reduction in residual error may be achieved by including risk factors as covariates. In this paper we show that the covariate design, indicating whether the covariates are measured at the cluster level or at the within-cluster subject level affects the estimation of the ICC, and hence the design effect. Therefore, the distinction between these two types of covariates should be made at the design stage. In this paper we use the nested-bootstrap method to assess the accuracy of the estimated ICC for continuous and binary response variables under different covariate structures. The codes of two SAS macros are made available by the authors for interested readers to facilitate the construction of confidence intervals for the ICC. Moreover, using Monte Carlo simulations we evaluate the relative efficiency of the estimators and evaluate the accuracy of the coverage probabilities of a 95% confidence interval on the population ICC. The methodology is illustrated using a published data set of blood pressure measurements taken on family members.

  5. A simple procedure for the comparison of covariance matrices

    Directory of Open Access Journals (Sweden)

    Garcia Carlos

    2012-11-01

    Full Text Available Abstract Background Comparing the covariation patterns of populations or species is a basic step in the evolutionary analysis of quantitative traits. Here I propose a new, simple method to make this comparison in two population samples that is based on comparing the variance explained in each sample by the eigenvectors of its own covariance matrix with that explained by the covariance matrix eigenvectors of the other sample. The rationale of this procedure is that the matrix eigenvectors of two similar samples would explain similar amounts of variance in the two samples. I use computer simulation and morphological covariance matrices from the two morphs in a marine snail hybrid zone to show how the proposed procedure can be used to measure the contribution of the matrices orientation and shape to the overall differentiation. Results I show how this procedure can detect even modest differences between matrices calculated with moderately sized samples, and how it can be used as the basis for more detailed analyses of the nature of these differences. Conclusions The new procedure constitutes a useful resource for the comparison of covariance matrices. It could fill the gap between procedures resulting in a single, overall measure of differentiation, and analytical methods based on multiple model comparison not providing such a measure.

  6. Newton law in covariant unimodular F(R) gravity

    Science.gov (United States)

    Nojiri, S.; Odintsov, S. D.; Oikonomou, V. K.

    2016-09-01

    We investigate the Newton law in the unimodular F(R) gravity. In the standard F(R) gravity, due to the extra scalar mode, there often appear the large corrections to the Newton law and such models are excluded by the experiments and/or the observations. In the unimodular F(R) gravity, however, the extra scalar mode become not to be dynamical due to the unimodular constraint and there is not any correction to the Newton law. Even in the unimodular Einstein gravity, the Newton law is reproduced but the mechanism is a little bit different from that in the unimodular F(R) gravity. We also investigate the unimodular F(R) gravity in the covariant formulation. In the covariant formulation, we include the three-form field. We show that the three-form field could not have any unwanted property, like ghost nor correction to the Newton law. In the covariant formulation, however, the above extra scalar mode becomes dynamical and could give a correction to the Newton law. We also show that there are no difference in the Friedmann-Robertson-Walker (FRW) dynamics in the non-covariant and covariant formulation.

  7. Covariant Lyapunov vectors of chaotic Rayleigh-Bénard convection.

    Science.gov (United States)

    Xu, M; Paul, M R

    2016-06-01

    We explore numerically the high-dimensional spatiotemporal chaos of Rayleigh-Bénard convection using covariant Lyapunov vectors. We integrate the three-dimensional and time-dependent Boussinesq equations for a convection layer in a shallow square box geometry with an aspect ratio of 16 for very long times and for a range of Rayleigh numbers. We simultaneously integrate many copies of the tangent space equations in order to compute the covariant Lyapunov vectors. The dynamics explored has fractal dimensions of 20≲D_{λ}≲50, and we compute on the order of 150 covariant Lyapunov vectors. We use the covariant Lyapunov vectors to quantify the degree of hyperbolicity of the dynamics and the degree of Oseledets splitting and to explore the temporal and spatial dynamics of the Lyapunov vectors. Our results indicate that the chaotic dynamics of Rayleigh-Bénard convection is nonhyperbolic for all of the Rayleigh numbers we have explored. Our results yield that the entire spectrum of covariant Lyapunov vectors that we have computed are tangled as indicated by near tangencies with neighboring vectors. A closer look at the spatiotemporal features of the Lyapunov vectors suggests contributions from structures at two different length scales with differing amounts of localization.

  8. What are the living conditions and health status of those who don’t report their migration status? a population-based study in Chile

    Directory of Open Access Journals (Sweden)

    Cabieses Baltica

    2012-11-01

    Full Text Available Abstract Background Undocumented immigrants are likely to be missing from population databases, making it impossible to identify an accurate sampling frame in migration research. No population-based data has been collected in Chile regarding the living conditions and health status of undocumented immigrants. However, the CASEN survey (Caracterizacion Socio- Economica Nacional asked about migration status in Chile for the first time in 2006 and provides an opportunity to set the base for future analysis of available migration data. We explored the living conditions and health of self-reported immigrants and respondents who preferred not to report their migration status in this survey. Methods Cross-sectional secondary analysis of CASEN survey in Chile in 2006. Outcomes: any disability, illness/accident, hospitalization/surgery, cancer/chronic condition (all binary variables; and the number of medical/emergency attentions received (count variables. Covariates: Demographics (age, sex, marital status, urban/rural, ethnicity, socioeconomic status (education level, employment status and household income, and material standard of living (overcrowding, sanitation, housing quality. Weighted regression models were estimated for each health outcome, crude and adjusted by sets of covariates, in STATA 10.0. Results About 1% of the total sample reported being immigrants and 0.7% preferred not to report their migration status (Migration Status - Missing Values; MS-MV. The MS-MV lived in more deprived conditions and reported a higher rate of health problems than immigrants. Some gender differences were observed by health status among immigrants and the MS-MV but they were not statistically significant. Regressions indicated that age, sex, SES and material factors consistently affected MS-MVs’ chance of presenting poor health and these patterns were different to those found among immigrants. Great heterogeneity in both the MS-MV and the immigrants, as

  9. Assessing environmental drivers of microbial communities in estuarine soils of the Aconcagua River in Central Chile.

    Science.gov (United States)

    Fuentes, Sebastián; Ding, Guo-Chun; Cárdenas, Franco; Smalla, Kornelia; Seeger, Michael

    2015-10-01

    Aconcagua River basin (Central Chile) harbors diverse economic activities such as agriculture, mining and a crude oil refinery. The aim of this study was to assess environmental drivers of microbial communities in Aconcagua River estuarine soils, which may be influenced by anthropogenic activities taking place upstream and by natural processes such as tides and flood runoffs. Physicochemical parameters were measured in floodplain soils along the estuary. Bacteria, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Pseudomonas, Bacillus and Fungi were studied by DGGE fingerprinting of 16S rRNA gene and ribosomal ITS-1 amplified from community DNA. Correlations between environment and communities were assessed by distance-based redundancy analysis. Mainly hydrocarbons, pH and the composed variable copper/arsenic/calcium but in less extent nitrogen and organic matter/phosphorous/magnesium correlated with community structures at different taxonomic levels. Aromatic hydrocarbons degradation potential by bacterial community was studied. Polycyclic aromatic hydrocarbon ring-hydroxylating dioxygenases genes were detected only at upstream sites. Naphthalene dioxygenase ndo genes were heterogeneously distributed along estuary, and related to Pseudomonas, Delftia, Comamonas and Ralstonia. IncP-1 plasmids were mainly present at downstream sites, whereas IncP-7 and IncP-9 plasmids showed a heterogeneous distribution. This study strongly suggests that pH, copper, arsenic and hydrocarbons are main drivers of microbial communities in Aconcagua River estuarine soils.

  10. Phylogenetic analysis and taxonomic revision of Physodactylinae (Coleoptera, Elateridae

    Directory of Open Access Journals (Sweden)

    Simone Policena Rosa

    2014-01-01

    Full Text Available A phylogeny based on male morphological characters and taxonomic revision of the Physodactylinae genera are presented. The phylogenetic analysis based on 66 male characters resulted in the polyphyly of Physodactylinae which comprises four independent lineages. Oligostethius and Idiotropia from Africa were found to be sister groups. Teslasena from Brazil was corroborated as belonging to Cardiophorinae clade. The South American genera Physodactylus and Dactylophysus were found to be sister groups and phylogenetically related to Heterocrepidius species. The Oriental Toxognathus resulted as sister group of that clade plus (Dicrepidius ramicornis (Lissomus sp, Physorhynus erythrocephalus. Taxonomic revisions include diagnoses and redescriptions of genera and distributional records and illustrations of species. Key to species of Teslasena, Toxognathus, Dactylophysus and Physodactylus are also provided. Teslasena lucasi is synonymized with T. femoralis. A new species of Dactylophysus is described, D. hirtus sp. nov., and lectotypes are designated to non-conspecific D. mendax sensu Fleutiaux and Heterocrepidius mendax Candèze. Physodactylus niger is removed from synonymy under P. oberthuri; P. carreti is synonymized with P. niger; P. obesus and P. testaceus are synonymized with P. sulcatus. Nine new species are described in Physodactylus: P. asper sp. nov., P. brunneus sp. nov., P. chassaini sp. nov., P. flavifrons sp. nov., P. girardi sp. nov., P. gounellei sp. nov., P. latithorax sp. nov., P. patens sp. nov. and P. tuberculatus sp. nov.

  11. Taxonomic revision and phylogenetic analyses of rubber powdery mildew fungi.

    Science.gov (United States)

    Liyanage, K K; Khan, Sehroon; Brooks, Siraprapa; Mortimer, Peter E; Karunarathna, Samantha C; Xu, Jianchu; Hyde, Kevin D

    2017-02-09

    Powdery mildew is a fungal disease that infects a wide range of plants, including rubber trees, which results in a reduction of latex yields of up to 45%. The causal agent of powdery mildew of rubber was first described as Oidium heveae, but later morpho-molecular research suggested that in the past, O. heveae has been confused with Erysiphe quercicola. However, it is still under debate whether the causal agent should be classified as a species of the genus Erysiphe emend. or Golovinomyces and Podosphaera, respectively. Therefore, the aim of this study was to undertake the morpho-molecular characterization of powdery mildew species associated with rubber trees, thus resolving these taxonomic issues. Morphological observation under light and scanning electron microscopes (SEM) clearly identified two morphotypes of the rubber powdery mildew. With the support of morphological and phylogenetic data, one of the two morphotypes was identified as the asexual morph of E. quercicola, while the second morphotype is still insufficiently known and according to the morphological results obtained we assume that it might belong to the genus Golovinomyces. More collections and additional molecular data are required for final conclusions regarding the exact taxonomic position of the second morphotype of rubber powdery mildew and its relation to the name O. heveae. The haplotype analysis identified eight haplotype groups of E. quercicola indicating the high genetic diversity of the species.

  12. TRANSPARENCIA Y LEYES SECRETAS EN CHILE

    Directory of Open Access Journals (Sweden)

    Pablo Contreras V.

    2010-01-01

    Full Text Available El autor analiza el problema de constitucionalidad de las leyes secretas en Chile, en razón de las modificaciones introducidas a la Constitución en el 2005. Primero, describe brevemente el fundamento sobre la publicidad de la ley en el Estado Democrático. Luego, se analiza el nuevo principio constitucional de publicidad establecido en el artículo 8º de la Constitución. Adicionalmente, se examina la constitucionalidad de las leyes secretas desde dos puntos de vista: confrontando la compatibilidad con el principio general de transparencia -como base de la institucionalidad- y analizando la afectación en el contenido esencial del derecho fundamental de acceso a la información pública.

  13. Three halls for music performance in Chile

    Science.gov (United States)

    Delannoy, Jaime; Heuffemann, Carolina; Ramirez, Daniel; Galvez, Fernando

    2002-11-01

    The primary purpose of this work was to investigate about the present acoustic conditions of used architectonic spaces in Santiago of Chile for orchestras of classic music performance. The studied halls were three: Aula Magna Universidad de Santiago, Teatro Municipal de Nunoa, and Teatro Baquedano. The used methodology was based on studies made by L. Beranek, M. Barron, among others, in concert halls worldwide. As it guides, for the measurement procedure, physical parameters RT, EDT, C50, C80, LF, BR, G, U50 were evaluated according to norm ISO 3382. On the other hand, it has been defined, to proposal way, a questionnaire of subjective valuation directed to musicians, specialized conductors, and listeners.

  14. A DRONE FLIGHT OVER PARANAL, CHILE

    CERN Document Server

    2016-01-01

    Aerial clip (shot using a drone and a Go pro) describing ESO's astronomical observatory facilities in the Atacama desert, Northern Chile. Locations covered by the drone flight include Cerro Paranal, with the Residencia (external and internal views) and the Very Large Telescope facility on Cerro Paranal, from above and with a peek into Unit Telescope 1 and its 8,2 m diameter mirror; final image on Cerro Armazones, the site chosen for building ESO's next telescope, the E-ELT (European Extremely Large Telescope). With a 39-metre main mirror, it will be the largest optical/near-infrared telescope in the world. The Argentinian Codillera with the Llullaillaco volcano are visible in the background.

  15. Sobre lectura y escritura en Chile

    Directory of Open Access Journals (Sweden)

    Grínor Rojo

    2011-11-01

    Full Text Available Los estudios de los últimos años realizados en Chile sobre lectura, competencia de lectura y lectura de noticias sobre política, revelan valores negativos que rondan el 50. Estos datos, a los que se suman los cuarenta millones de analfabetos en América Latina, están en la base del rechazo en este artículo de la afirmación de la muerte del libro y de la frívola fe en el reemplazo del libro por el uso de las tecnologías de la información y la comunicación (llenar de computadoras las escuelas, insistiendo en cambio en atender seriamente a los lazos entre razón, libro y lectura en el desarrollo individual y de la sociedad

  16. Sobre lectura y escritura en Chile

    OpenAIRE

    Grínor Rojo

    2011-01-01

    Los estudios de los últimos años realizados en Chile sobre lectura, competencia de lectura y lectura de noticias sobre política, revelan valores negativos que rondan el 50. Estos datos, a los que se suman los cuarenta millones de analfabetos en América Latina, están en la base del rechazo en este artículo de la afirmación de la muerte del libro y de la frívola fe en el reemplazo del libro por el uso de las tecnologías de la información y la comunicación (llenar de computadoras las escuelas), ...

  17. Los valores del urbanismo en Chile

    Directory of Open Access Journals (Sweden)

    Waldo López Moya

    2015-04-01

    Full Text Available En el mes de junio de 2004 fue presentado al Senado de Chile un proyecto de ley destinado a modificar la Ley General de Urbanismo y Construcciones (LGUC, con el fin de adecuarla para permitir la formación y edificación de «áreas urbanas condicionadas» (AUC. Esto es, conjuntos residenciales urbanos, construidos fuera del límite urbano convencional. Unos, en áreas rurales ubicadas inmediatamente adyacentes al mismo, llamadas «áreas de extensión urbana condicionada» (AEUC, y otros, ubicados en áreas rurales segregadas, denominadas «áreas de desarrollo urbano condicionado» (ADUC.

  18. Improving the effectiveness of rural development policy in Chile

    NARCIS (Netherlands)

    Carter Leal, L.M.

    2016-01-01

    In Chile, agriculture remains a key economic factor for rural development. Accordingly, the Chilean government, through the Agricultural Development Institute (INDAP), provides financial support for fostering entrepreneurship among small farmers to enable them to become more competitive in global ma

  19. Femtosecond Studies Of Coulomb Explosion Utilizing Covariance Mapping

    CERN Document Server

    Card, D A

    2000-01-01

    The studies presented herein elucidate details of the Coulomb explosion event initiated through the interaction of molecular clusters with an intense femtosecond laser beam (≥1 PW/cm2). Clusters studied include ammonia, titanium-hydrocarbon, pyridine, and 7-azaindole. Covariance analysis is presented as a general technique to study the dynamical processes in clusters and to discern whether the fragmentation channels are competitive. Positive covariance determinations identify concerted processes such as the concomitant explosion of protonated cluster ions of asymmetrical size. Anti- covariance mapping is exploited to distinguish competitive reaction channels such as the production of highly charged nitrogen atoms formed at the expense of the protonated members of a cluster ion ensemble. This technique is exemplified in each cluster system studied. Kinetic energy analyses, from experiment and simulation, are presented to fully understand the Coulomb explosion event. A cutoff study strongly suggests that...

  20. Data Covariances from R-Matrix Analyses of Light Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Hale, G.M., E-mail: ghale@lanl.gov; Paris, M.W.

    2015-01-15

    After first reviewing the parametric description of light-element reactions in multichannel systems using R-matrix theory and features of the general LANL R-matrix analysis code EDA, we describe how its chi-square minimization procedure gives parameter covariances. This information is used, together with analytically calculated sensitivity derivatives, to obtain cross section covariances for all reactions included in the analysis by first-order error propagation. Examples are given of the covariances obtained for systems with few resonances ({sup 5}He) and with many resonances ({sup 13}C ). We discuss the prevalent problem of this method leading to cross section uncertainty estimates that are unreasonably small for large data sets. The answer to this problem appears to be using parameter confidence intervals in place of standard errors.

  1. Full covariance of CMB and lensing reconstruction power spectra

    CERN Document Server

    Peloton, Julien; Lewis, Antony; Carron, Julien; Zahn, Oliver

    2016-01-01

    CMB and lensing reconstruction power spectra are powerful probes of cosmology. However they are correlated, since the CMB power spectra are lensed and the lensing reconstruction is constructed using CMB multipoles. We perform a full analysis of the auto- and cross-covariances, including polarization power spectra and minimum variance lensing estimators, and compare with simulations of idealized future CMB-S4 observations. Covariances sourced by fluctuations in the unlensed CMB and instrumental noise can largely be removed by using a realization-dependent subtraction of lensing reconstruction noise, leaving a relatively simple covariance model that is dominated by lensing-induced terms and well described by a small number of principal components. The correlations between the CMB and lensing power spectra will be detectable at the level of $\\sim 5\\sigma$ for a CMB-S4 mission, and neglecting those could underestimate some parameter error bars by several tens of percent. However we found that the inclusion of ext...

  2. Adaptive Covariance Inflation in a Multi-Resolution Assimilation Scheme

    Science.gov (United States)

    Hickmann, K. S.; Godinez, H. C.

    2015-12-01

    When forecasts are performed using modern data assimilation methods observation and model error can be scaledependent. During data assimilation the blending of error across scales can result in model divergence since largeerrors at one scale can be propagated across scales during the analysis step. Wavelet based multi-resolution analysiscan be used to separate scales in model and observations during the application of an ensemble Kalman filter. However,this separation is done at the cost of implementing an ensemble Kalman filter at each scale. This presents problemswhen tuning the covariance inflation parameter at each scale. We present a method to adaptively tune a scale dependentcovariance inflation vector based on balancing the covariance of the innovation and the covariance of observations ofthe ensemble. Our methods are demonstrated on a one dimensional Kuramoto-Sivashinsky (K-S) model known todemonstrate non-linear interactions between scales.

  3. Flavour Covariant Transport Equations: an Application to Resonant Leptogenesis

    CERN Document Server

    Dev, P S Bhupal; Pilaftsis, Apostolos; Teresi, Daniele

    2014-01-01

    We present a fully flavour-covariant formalism for transport phenomena, by deriving Markovian master equations that describe the time-evolution of particle number densities in a statistical ensemble with arbitrary flavour content. As an application of this general formalism, we study flavour effects in a scenario of resonant leptogenesis (RL) and obtain the flavour-covariant evolution equations for heavy-neutrino and lepton number densities. This provides a complete and unified description of RL, capturing three relevant physical phenomena: (i) the resonant mixing between the heavy-neutrino states, (ii) coherent oscillations between different heavy-neutrino flavours, and (iii) quantum decoherence effects in the charged-lepton sector. To illustrate the importance of this formalism, we numerically solve the flavour-covariant rate equations for a minimal RL model and show that the total lepton asymmetry can be enhanced up to one order of magnitude, as compared to that obtained from flavour-diagonal or partially ...

  4. Residual noise covariance for Planck low-resolution data analysis

    CERN Document Server

    Keskitalo, R; Cabella, P; Kisner, T; Poutanen, T; Stompor, R; Bartlett, J G; Borrill, J; Cantalupo, C; De Gasperis, G; De Rosa, A; de Troia, G; Eriksen, H K; Finelli, F; Górski, K M; Gruppuso, A; Hivon, E; Jaffe, A; Keihanen, E; Kurki-Suonio, H; Lawrence, C R; Natoli, P; Paci, F; Polenta, G; Rocha, G

    2009-01-01

    Aims: Develop and validate tools to estimate residual noise covariance in Planck frequency maps. Quantify signal error effects and compare different techniques to produce low-resolution maps. Methods: We derive analytical estimates of covariance of the residual noise contained in low-resolution maps produced using a number of map-making approaches. We test these analytical predictions using Monte Carlo simulations and their impact on angular power spectrum estimation. We use simulations to quantify the level of signal errors incurred in different resolution downgrading schemes considered in this work. Results: We find an excellent agreement between the optimal residual noise covariance matrices and Monte Carlo noise maps. For destriping map-makers, the extent of agreement is dictated by the knee frequency of the correlated noise component and the chosen baseline offset length. The significance of signal striping is shown to be insignificant when properly dealt with. In map resolution downgrading, we find that...

  5. Galaxy-galaxy lensing estimators and their covariance properties

    CERN Document Server

    Singh, Sukhdeep; Seljak, Uroš; Slosar, Anže; Gonzalez, Jose Vazquez

    2016-01-01

    We study the covariance properties of real space correlation function estimators -- primarily galaxy-shear correlations, or galaxy-galaxy lensing -- using SDSS data for both shear catalogs and lenses (specifically the BOSS LOWZ sample). Using mock catalogs of lenses and sources, we disentangle the various contributions to the covariance matrix and compare them with a simple analytical model. We show that not subtracting the lensing measurement around random points from the measurement around the lens sample is equivalent to performing the measurement using the density field instead of the over-density field, and that this leads to a significant error increase due to an additional term in the covariance. Therefore, this subtraction should be performed regardless of its beneficial effects on systematics. Comparing the error estimates from data and mocks for estimators that involve the over-density, we find that the errors are dominated by the shape noise and lens clustering, that empirically estimated covarianc...

  6. Neutron Cross Section Covariances for Structural Materials and Fission Products

    Science.gov (United States)

    Hoblit, S.; Cho, Y.-S.; Herman, M.; Mattoon, C. M.; Mughabghab, S. F.; Obložinský, P.; Pigni, M. T.; Sonzogni, A. A.

    2011-12-01

    We describe neutron cross section covariances for 78 structural materials and fission products produced for the new US evaluated nuclear reaction library ENDF/B-VII.1. Neutron incident energies cover full range from 10 eV to 20 MeV and covariances are primarily provided for capture, elastic and inelastic scattering as well as (n,2n). The list of materials follows priorities defined by the Advanced Fuel Cycle Initiative, the major application being data adjustment for advanced fast reactor systems. Thus, in addition to 28 structural materials and 49 fission products, the list includes also 23Na which is important fast reactor coolant. Due to extensive amount of materials, we adopted a variety of methodologies depending on the priority of a specific material. In the resolved resonance region we primarily used resonance parameter uncertainties given in Atlas of Neutron Resonances and either applied the kernel approximation to propagate these uncertainties into cross section uncertainties or resorted to simplified estimates based on integral quantities. For several priority materials we adopted MF32 covariances produced by SAMMY at ORNL, modified by us by adding MF33 covariances to account for systematic uncertainties. In the fast neutron region we resorted to three methods. The most sophisticated was EMPIRE-KALMAN method which combines experimental data from EXFOR library with nuclear reaction modeling and least-squares fitting. The two other methods used simplified estimates, either based on the propagation of nuclear reaction model parameter uncertainties or on a dispersion analysis of central cross section values in recent evaluated data files. All covariances were subject to quality assurance procedures adopted recently by CSEWG. In addition, tools were developed to allow inspection of processed covariances and computed integral quantities, and for comparing these values to data from the Atlas and the astrophysics database KADoNiS.

  7. Neutron Cross Section Covariances for Structural Materials and Fission Products

    Energy Technology Data Exchange (ETDEWEB)

    Hoblit, S.; Hoblit,S.; Cho,Y.-S.; Herman,M.; Mattoon,C.M.; Mughabghab,S.F.; Oblozinsky,P.; Pigni,M.T.; Sonzogni,A.A.

    2011-12-01

    We describe neutron cross section covariances for 78 structural materials and fission products produced for the new US evaluated nuclear reaction library ENDF/B-VII.1. Neutron incident energies cover full range from 10{sup -5} eV to 20 MeV and covariances are primarily provided for capture, elastic and inelastic scattering as well as (n,2n). The list of materials follows priorities defined by the Advanced Fuel Cycle Initiative, the major application being data adjustment for advanced fast reactor systems. Thus, in addition to 28 structural materials and 49 fission products, the list includes also {sup 23}Na which is important fast reactor coolant. Due to extensive amount of materials, we adopted a variety of methodologies depending on the priority of a specific material. In the resolved resonance region we primarily used resonance parameter uncertainties given in Atlas of Neutron Resonances and either applied the kernel approximation to propagate these uncertainties into cross section uncertainties or resorted to simplified estimates based on integral quantities. For several priority materials we adopted MF32 covariances produced by SAMMY at ORNL, modified by us by adding MF33 covariances to account for systematic uncertainties. In the fast neutron region we resorted to three methods. The most sophisticated was EMPIRE-KALMAN method which combines experimental data from EXFOR library with nuclear reaction modeling and least-squares fitting. The two other methods used simplified estimates, either based on the propagation of nuclear reaction model parameter uncertainties or on a dispersion analysis of central cross section values in recent evaluated data files. All covariances were subject to quality assurance procedures adopted recently by CSEWG. In addition, tools were developed to allow inspection of processed covariances and computed integral quantities, and for comparing these values to data from the Atlas and the astrophysics database KADoNiS.

  8. Chile: Political and Economic Conditions and U.S. Relations

    Science.gov (United States)

    2009-01-12

    Chile: Country Report,” Economist Intelligence Unit, December 2008. 32 Eva Vergara, “Bachelet Crea Comisión para Enfrenter Desempleo por Crisis...sexual and labor exploitation. The U.S. Department of State’s 2008 Trafficking in Persons (TIP) Report states that Chile does not fully comply with the...minimum standards for the elimination of trafficking because it’s statutory framework does not specifically prohibit labor trafficking. However

  9. Wirtschaftliche Stellung deutscher Unternehmen in Chile: Ergebnisse einer empirischen Analyse

    OpenAIRE

    Kassai, László B.

    2014-01-01

    Die Abschätzung der wirtschaftlichen Bedeutung deutscher Unternehmen in Chile anhand der Auswertung von 14 schriftlichen Interviews mit deutschen Tochtergesellschaften im Jahre 1987 ist der Inhalt dieses Beitrages. Die Einordnung erfolgt vor dem Hintergrund sowohl der wirtschaftlichen Situation der ganzen Region (Lateinamerika) als auch der industriellen Entwicklung in Chile bis 1987. Die Analyse kommt zum Schluß, daß die im Durchschnitt lang ansässigen Unternehmen a) eine rege Innovations...

  10. A scale invariant covariance structure on jet space

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2005-01-01

    This paper considers scale invariance of statistical image models. We study statistical scale invariance of the covariance structure of jet space under scale space blurring and derive the necessary structure and conditions of the jet covariance matrix in order for it to be scale invariant. As part...... of the derivation, we introduce a blurring operator At that acts on jet space contrary to doing spatial filtering and a scaling operator Ss. The stochastic Brownian image model is an example of a class of functions which are scale invariant with respect to the operators At and Ss. This paper also includes empirical...

  11. Neutron Resonance Parameters and Covariance Matrix of 239Pu

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, Herve [ORNL; Leal, Luiz C [ORNL; Larson, Nancy M [ORNL

    2008-08-01

    In order to obtain the resonance parameters in a single energy range and the corresponding covariance matrix, a reevaluation of 239Pu was performed with the code SAMMY. The most recent experimental data were analyzed or reanalyzed in the energy range thermal to 2.5 keV. The normalization of the fission cross section data was reconsidered by taking into account the most recent measurements of Weston et al. and Wagemans et al. A full resonance parameter covariance matrix was generated. The method used to obtain realistic uncertainties on the average cross section calculated by SAMMY or other processing codes was examined.

  12. Some Algorithms for the Conditional Mean Vector and Covariance Matrix

    Directory of Open Access Journals (Sweden)

    John F. Monahan

    2006-08-01

    Full Text Available We consider here the problem of computing the mean vector and covariance matrix for a conditional normal distribution, considering especially a sequence of problems where the conditioning variables are changing. The sweep operator provides one simple general approach that is easy to implement and update. A second, more goal-oriented general method avoids explicit computation of the vector and matrix, while enabling easy evaluation of the conditional density for likelihood computation or easy generation from the conditional distribution. The covariance structure that arises from the special case of an ARMA(p, q time series can be exploited for substantial improvements in computational efficiency.

  13. A Blind Detection Algorithm Utilizing Statistical Covariance in Cognitive Radio

    Directory of Open Access Journals (Sweden)

    Yingxue Li

    2012-11-01

    Full Text Available As the expression of performance parameters are obtained using asymptotic method in most blind covariance detection algorithm, the paper presented a new blind detection algorithm using cholesky factorization. Utilizing random matrix theory, we derived the performance parameters using non-asymptotic method. The proposed method overcomes the noise uncertainty problem and performs well without any information about the channel, primary user and noise. Numerical simulation results demonstrate that the performance parameters expressions are correct and the new detector outperforms the other blind covariance detectors.

  14. On spectral distribution of high dimensional covariation matrices

    DEFF Research Database (Denmark)

    Heinrich, Claudio; Podolskij, Mark

    In this paper we present the asymptotic theory for spectral distributions of high dimensional covariation matrices of Brownian diffusions. More specifically, we consider N-dimensional Itô integrals with time varying matrix-valued integrands. We observe n equidistant high frequency data points...... of the underlying Brownian diffusion and we assume that N/n -> c in (0,oo). We show that under a certain mixed spectral moment condition the spectral distribution of the empirical covariation matrix converges in distribution almost surely. Our proof relies on method of moments and applications of graph theory....

  15. Positive semidefinite integrated covariance estimation, factorizations and asynchronicity

    DEFF Research Database (Denmark)

    Sauri, Orimar; Lunde, Asger; Laurent, Sébastien;

    2017-01-01

    An estimator of the ex-post covariation of log-prices under asynchronicity and microstructure noise is proposed. It uses the Cholesky factorization of the covariance matrix in order to exploit the heterogeneity in trading intensities to estimate the different parameters sequentially with as many...... observations as possible. The estimator is positive semidefinite by construction. We derive asymptotic results and confirm their good finite sample properties by means of a Monte Carlo simulation. In the application we forecast portfolio Value-at-Risk and sector risk exposures for a portfolio of 52 stocks. We...

  16. The covariant electromagnetic Casimir effect for real conducting spherical shells

    CERN Document Server

    Razmi, H

    2016-01-01

    Using the covariant electromagnetic Casimir effect (previously introduced for real conducting cylindrical shells [1]), the Casimir force experienced by a spherical shell, under Dirichlet boundary condition, is calculated. The renormalization procedure is based on the plasma cut-off frequency for real conductors. The real case of a gold (silver) sphere is considered and the corresponding electromagnetic Casimir force is computed. In the covariant approach, there isn't any decomposition of fields to TE and TM modes; thus, we do not need to consider the Neumann boundary condition in parallel to the Dirichlet problem and then add their corresponding results.

  17. On Variance and Covariance for Bounded Linear Operators

    Institute of Scientific and Technical Information of China (English)

    Chia Shiang LIN

    2001-01-01

    In this paper we initiate a study of covariance and variance for two operators on a Hilbert space, proving that the c-v (covariance-variance) inequality holds, which is equivalent to the CauchySchwarz inequality. As for applications of the c-v inequality we prove uniformly the Bernstein-type incqualities and equalities, and show the generalized Heinz-Kato-Furuta-type inequalities and equalities,from which a generalization and sharpening of Reid's inequality is obtained. We show that every operator can be expressed as a p-hyponormal-type, and a hyponornal-type operator. Finally, some new characterizations of the Furuta inequality are given.

  18. Estimating surface fluxes using eddy covariance and numerical ogive optimization

    DEFF Research Database (Denmark)

    Sievers, J.; Papakyriakou, T.; Larsen, Søren Ejling;

    2015-01-01

    Estimating representative surface fluxes using eddy covariance leads invariably to questions concerning inclusion or exclusion of low-frequency flux contributions. For studies where fluxes are linked to local physical parameters and up-scaled through numerical modelling efforts, low-frequency con......Estimating representative surface fluxes using eddy covariance leads invariably to questions concerning inclusion or exclusion of low-frequency flux contributions. For studies where fluxes are linked to local physical parameters and up-scaled through numerical modelling efforts, low...

  19. High-dimensional covariance matrix estimation with missing observations

    CERN Document Server

    Lounici, Karim

    2012-01-01

    In this paper, we study the problem of high-dimensional approximately low-rank covariance matrix estimation with missing observations. We propose a simple procedure computationally tractable in high-dimension and that does not require imputation of the missing data. We establish non-asymptotic sparsity oracle inequalities for the estimation of the covariance matrix with the Frobenius and spectral norms, valid for any setting of the sample size and the dimension of the observations. We further establish minimax lower bounds showing that our rates are minimax optimal up to a logarithmic factor.

  20. Glycosides from Marine Sponges (Porifera, Demospongiae: Structures, Taxonomical Distribution, Biological Activities and Biological Roles

    Directory of Open Access Journals (Sweden)

    Valentin A. Stonik

    2012-08-01

    Full Text Available Literature data about glycosides from sponges (Porifera, Demospongiae are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed.

  1. Glycosides from marine sponges (Porifera, Demospongiae): structures, taxonomical distribution, biological activities and biological roles.

    Science.gov (United States)

    Kalinin, Vladimir I; Ivanchina, Natalia V; Krasokhin, Vladimir B; Makarieva, Tatyana N; Stonik, Valentin A

    2012-08-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed.

  2. Covariant Spectator Theory of heavy-light and heavy mesons and the predictive power of covariant interaction kernels

    CERN Document Server

    Leitão, Sofia; Peña, M T; Biernat, Elmar P

    2016-01-01

    The Covariant Spectator Theory (CST) is used to calculate the mass spectrum and vertex functions of heavy-light and heavy mesons in Minkowski space. The covariant kernel contains Lorentz scalar, pseudoscalar, and vector contributions. The numerical calculations are performed in momentum space, where special care is taken to treat the strong singularities present in the confining kernel. The observed meson spectrum is very well reproduced after fitting a small number of model parameters. Remarkably, a fit to a few pseudoscalar meson states only, which are insensitive to spin-orbit and tensor forces and do not allow to separate the spin-spin from the central interaction, leads to essentially the same model parameters as a more general fit. This demonstrates that the covariance of the chosen interaction kernel is responsible for the very accurate prediction of the spin-dependent quark-antiquark interactions.

  3. Covariant Spectator Theory of heavy-light and heavy mesons and the predictive power of covariant interaction kernels

    Science.gov (United States)

    Leitão, Sofia; Stadler, Alfred; Peña, M. T.; Biernat, Elmar P.

    2017-01-01

    The Covariant Spectator Theory (CST) is used to calculate the mass spectrum and vertex functions of heavy-light and heavy mesons in Minkowski space. The covariant kernel contains Lorentz scalar, pseudoscalar, and vector contributions. The numerical calculations are performed in momentum space, where special care is taken to treat the strong singularities present in the confining kernel. The observed meson spectrum is very well reproduced after fitting a small number of model parameters. Remarkably, a fit to a few pseudoscalar meson states only, which are insensitive to spin-orbit and tensor forces and do not allow to separate the spin-spin from the central interaction, leads to essentially the same model parameters as a more general fit. This demonstrates that the covariance of the chosen interaction kernel is responsible for the very accurate prediction of the spin-dependent quark-antiquark interactions.

  4. An Empirical State Error Covariance Matrix Orbit Determination Example

    Science.gov (United States)

    Frisbee, Joseph H., Jr.

    2015-01-01

    State estimation techniques serve effectively to provide mean state estimates. However, the state error covariance matrices provided as part of these techniques suffer from some degree of lack of confidence in their ability to adequately describe the uncertainty in the estimated states. A specific problem with the traditional form of state error covariance matrices is that they represent only a mapping of the assumed observation error characteristics into the state space. Any errors that arise from other sources (environment modeling, precision, etc.) are not directly represented in a traditional, theoretical state error covariance matrix. First, consider that an actual observation contains only measurement error and that an estimated observation contains all other errors, known and unknown. Then it follows that a measurement residual (the difference between expected and observed measurements) contains all errors for that measurement. Therefore, a direct and appropriate inclusion of the actual measurement residuals in the state error covariance matrix of the estimate will result in an empirical state error covariance matrix. This empirical state error covariance matrix will fully include all of the errors in the state estimate. The empirical error covariance matrix is determined from a literal reinterpretation of the equations involved in the weighted least squares estimation algorithm. It is a formally correct, empirical state error covariance matrix obtained through use of the average form of the weighted measurement residual variance performance index rather than the usual total weighted residual form. Based on its formulation, this matrix will contain the total uncertainty in the state estimate, regardless as to the source of the uncertainty and whether the source is anticipated or not. It is expected that the empirical error covariance matrix will give a better, statistical representation of the state error in poorly modeled systems or when sensor performance

  5. Estimation of water requirements and Kc values of 'Thompson Seedless' table grapes grown in the overhead trellis system, using the Eddy covariance method

    Directory of Open Access Journals (Sweden)

    Paulina Villagra

    2014-04-01

    Full Text Available Crop evapotranspiration (ETc is essential for irrigation scheduling. The amount of water consumed can be estimated by multiplying the reference evapotranspiration (ET0 by a crop coefficient (Kc; the value of Kc is usually obtained from FAO Paper nr 56. In table grapes (Vitis vinifera L., Kc are obtained from experiments in vines trained on trellis systems; however in Chile, the most used is the overhead trellis system (parronal. Therefore, the objective was to determine water requirements and Kc values of a table grape orchard cv. Thompson Seedless trained on an overhead trellis system in Calle Larga (32°52'40" S, 70°37'45" W, 795 m a.s.l., Aconcagua Valley, Chile, using the Eddy covariance method. During the 2008/2009 and 2009/2010 seasons, the instruments required for ET0 and ETc measurement were installed on a 4 m tower above the soil (2 m above vine canopy. The ET0 was estimated according to the FAO Penman-Monteith equation and ETc by the Eddy covariance method. The Kc was obtained by ratio between ETc and ET0. The maximum ETc was 7 mm d-1 and total water consumption was 810 mm. The season maximum Kc value of 1.2 was obtained near harvest during the first season, and 20 d before veraison in the second season. The Kc increased linearly with the percentage of intercepted solar radiation (IRS by the vine canopy at noon, suggesting that an equation to convert the IRS to Kc is more useful than Kc tabulated according to phenology. The equation obtained in this experiment was Kc = 0.012 IRS - 0.1029, R² = 0.85.

  6. Taxonomic Study of the Genus Abundisporus in Korea.

    Science.gov (United States)

    Jargalmaa, Suldbold; Park, Myung Soo; Park, Jae Young; Fong, Jonathan J; Jang, Yeongseon; Lim, Young Woon

    2015-09-01

    The polypore genus Abundisporus Ryvarden is characterized by resupinate to pileate fruitbodies with a purplish brown hymenophore, slightly thick-walled, pale yellowish and non-dextrinoid basidiospores, and causing white rot. A purple color hymenophore, an easily observable and striking character, was considered the main distinctive feature at the generic level within polypores. However, due to highly similar basidiocarp features, species identification within these purple polypores is particularly difficult. Three species of purple colored polypores have been reported in Korea (Abundisporus fuscopurpureus, A. pubertatis, and Fomitopsis rosea). Based on morphological re-examination, ecological information, and sequence analysis of the internal transcribed spacer, we showed that previous classification was incorrect and there is only one species (A. pubertatis) in Korea. We provide a detailed description of A. pubertatis in Korea, as well as a taxonomic key to distinguish wood rot fungi with a purple hymenophore.

  7. Flora of the city of Podgorica, Montenegro: Taxonomic analysis

    Directory of Open Access Journals (Sweden)

    Stešević Danijela

    2008-01-01

    Full Text Available In this paper we present the taxonomic segment of a floristic study undertaken in the city of Podgorica in the period of 2002-2007. The check-list of spontaneously growing vascular plants includes 1227 species and subspecies belonging to 545 genera and 118 families. The dominant families are Poaceae (11.7%, asteraceae (11.2% and Fabaceae (9.2%. The most abundant genera are Trifolium (2.1%, Euphorbia (1.5%, Carex (1.5%, Bromus (1.3% and Vicia (1.2%. Analysis of the flora of Podgorica in comparison with some other european cities showed that the flora of Podgorica is most similar to that of Rome (Q/S= 0,7.

  8. Fast and sensitive taxonomic classification for metagenomics with Kaiju

    DEFF Research Database (Denmark)

    Menzel, Peter; Ng, Kim Lee; Krogh, Anders

    2016-01-01

    The constantly decreasing cost and increasing output of current sequencing technologies enable large scale metagenomic studies of microbial communities from diverse habitats. Therefore, fast and accurate methods for taxonomic classification are needed, which can operate on increasingly larger...... datasets and reference databases. Recently, several fast metagenomic classifiers have been developed, which are based on comparison of genomic k-mers. However, nucleotide comparison using a fixed k-mer length often lacks the sensitivity to overcome the evolutionary distance between sampled species...... and genomes in the reference database. Here, we present the novel metagenome classifier Kaiju for fast assignment of reads to taxa. Kaiju finds maximum exact matches on the protein-level using the Borrows-Wheeler transform, and can optionally allow amino acid substitutions in the search using a greedy...

  9. Spectral Density of Sample Covariance Matrices of Colored Noise

    CERN Document Server

    Dolezal, Emil

    2008-01-01

    We study the dependence of the spectral density of the covariance matrix ensemble on the power spectrum of the underlying multivariate signal. The white noise signal leads to the celebrated Marchenko-Pastur formula. We demonstrate results for some colored noise signals.

  10. Eddy covariance based methane flux in Sundarbans mangroves, India

    Indian Academy of Sciences (India)

    Chandra Shekhar Jha; Suraj Reddy Rodda; Kiran Chand Thumaty; A K Raha; V K Dadhwal

    2014-07-01

    We report the initial results of the methane flux measured using eddy covariance method during summer months from the world’s largest mangrove ecosystem, Sundarbans of India. Mangrove ecosystems are known sources for methane (CH4) having very high global warming potential. In order to quantify the methane flux in mangroves, an eddy covariance flux tower was recently erected in the largest unpolluted and undisturbed mangrove ecosystem in Sundarbans (India). The tower is equipped with eddy covariance flux tower instruments to continuously measure methane fluxes besides the mass and energy fluxes. This paper presents the preliminary results of methane flux variations during summer months (i.e., April and May 2012) in Sundarbans mangrove ecosystem. The mean concentrations of CH4 emission over the study period was 1682 ± 956 ppb. The measured CH4 fluxes computed from eddy covariance technique showed that the study area acts as a net source for CH4 with daily mean flux of 150.22 ± 248.87 mg m−2 day−1. The methane emission as well as its flux showed very high variability diurnally. Though the environmental conditions controlling methane emission is not yet fully understood, an attempt has been made in the present study to analyse the relationships of methane efflux with tidal activity. This present study is part of Indian Space Research Organisation–Geosphere Biosphere Program (ISRO–GBP) initiative under ‘National Carbon Project’.

  11. High-dimensional Sparse Inverse Covariance Estimation using Greedy Methods

    CERN Document Server

    Johnson, Christopher C; Ravikumar, Pradeep

    2011-01-01

    In this paper we consider the task of estimating the non-zero pattern of the sparse inverse covariance matrix of a zero-mean Gaussian random vector from a set of iid samples. Note that this is also equivalent to recovering the underlying graph structure of a sparse Gaussian Markov Random Field (GMRF). We present two novel greedy approaches to solving this problem. The first estimates the non-zero covariates of the overall inverse covariance matrix using a series of global forward and backward greedy steps. The second estimates the neighborhood of each node in the graph separately, again using greedy forward and backward steps, and combines the intermediate neighborhoods to form an overall estimate. The principal contribution of this paper is a rigorous analysis of the sparsistency, or consistency in recovering the sparsity pattern of the inverse covariance matrix. Surprisingly, we show that both the local and global greedy methods learn the full structure of the model with high probability given just $O(d\\log...

  12. On a new normalization for tractor covariant derivatives

    CERN Document Server

    Hammerl, Matthias; Soucek, Vladimir; Silhan, Josef

    2010-01-01

    A regular normal parabolic geometry of type $G/P$ on a manifold $M$ gives rise to sequences $D_i$ of invariant differential operators, known as the curved version of the BGG resolution. These sequences are constructed from the normal covariant derivative $\

  13. Leading order covariant chiral nucleon-nucleon interaction

    CERN Document Server

    Ren, Xiu-Lei; Geng, Li-Sheng; Long, Bing-Wei; Ring, Peter; Meng, Jie

    2016-01-01

    Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the strong need for a covariant chiral force in relativistic nuclear structure studies, we develop a new covariant scheme to construct the nucleon-nucleon interaction in the framework of chiral effective field theory. The chiral interaction is formulated up to leading order with a covariant power counting and a Lorentz invariant chiral Lagrangian. We find that the covariant scheme induces all the six invariant spin operators needed to describe the nuclear force, which are also helpful to achieve cutoff independence for certain partial waves. A detailed investigation of the partial wave potentials shows a better description of the scattering phase shifts with low angular momenta than the leading order Weinberg approach. Particularly, the description of the $^1S_0$, $^3P_0$, and $^1P_1$ partial waves is similar to that of the next-to-leading order Weinberg approach. Our study shows that the relativistic fr...

  14. Modeling the Conditional Covariance between Stock and Bond Returns

    NARCIS (Netherlands)

    P. de Goeij (Peter); W.A. Marquering (Wessel)

    2002-01-01

    textabstractTo analyze the intertemporal interaction between the stock and bond market returns, we allow the conditional covariance matrix to vary over time according to a multivariate GARCH model similar to Bollerslev, Engle and Wooldridge (1988). We extend the model such that it allows for asymmet

  15. Covariate-adjusted measures of discrimination for survival data

    NARCIS (Netherlands)

    White, Ian R.; Rapsomaniki, Eleni; Wannamethee, S. G.; Morris, R. W.; Willeit, J.; Willeit, P.; Santer, P.; Kiechl, S.; Wald, N.; Ebrahim, S.; Lawlor, D. A.; Gallacher, J.; Yarnell, J. W G; Ben-Shlomo, Y.; Casiglia, E.; Tikhonoff, V.; Sutherland, S. E.; Nietert, P. J.; Keil, J. E.; Bachman, D. L.; Psaty, B. M.; Cushman, M.; Nordestgaard, B. G.; Tybjærg-Hansen, A.; Frikke-Schmidt, R.; Giampaoli, S.; Palmieri, L.; Panico, S.; Pilotto, L.; Vanuzzo, D.; Simons, L. A.; Friedlander, Y.; McCallum, J.; Price, J. F.; McLachlan, S.; Taylor, J. O.; Guralnik, J. M.; Wallace, R. B.; Kohout, F. J.; Cornoni-Huntley, J. C.; Guralnik, J. M.; Blazer, D. G.; Guralnik, J. M.; Phillips, C. L.; Phillips, C. L.; Guralnik, J. M.; Wareham, N. J.; Khaw, K. T.; Brenner, H.; Schöttker, B.; Müller, H. T.; Rothenbacher, D.; Nissinen, A.; Donfrancesco, C.; Giampaoli, S.; Harald, K.; Jousilahti, P. R.; Vartiainen, E.; Salomaa, V.; D'Agostino, R. B.; Wolf, P. A.; Vasan, R. S.; Daimon, M.; Oizumi, T.; Kayama, T.; Kato, T.; Chetrit, A.; Dankner, R.; Lubin, F.; Welin, L.; Svärdsudd, K.; Eriksson, H.; Lappas, G.; Lissner, L.; Mehlig, K.; Björkelund, C.; Nagel, D.; Kiyohara, Y.; Arima, H.; Ninomiya, T.; Hata, J.; Rodriguez, B.; Dekker, J. M.; Nijpels, G.; Stehouwer, C. D A; Iso, H.; Kitamura, A.; Yamagishi, K.; Noda, H.; Goldbourt, U.; Kauhanen, J.; Salonen, J. T.; Tuomainen, T. P.; Meade, T. W.; DeStavola, B. L.; Blokstra, A.; Verschuren, W. M M; Cushman, M.; de Boer, I. H.; Folsom, A. R.; Psaty, B. M.; Koenig, W.; Meisinger, C.; Peters, A.; Verschuren, W. M M; Bueno-de-Mesquita, H. B.; Blokstra, A.; Rosengren, A.; Wilhelmsen, L.; Lappas, G.; Kuller, L. H.; Grandits, G.; Cooper, J. A.; Bauer, K. A.; Davidson, K. W.; Kirkland, S.; Shaffer, J. A.; Shimbo, D.; Kitamura, A.; Iso, H.; Sato, S.; Dullaart, R. P F; Bakker, S. J L; Gansevoort, R. T.; Ducimetiere, P.; Amouyel, P.; Arveiler, D.; Evans, A.; Ferrières, J.; Schulte, H.; Assmann, G.; Jukema, J. W.; Westendorp, R. G J; Sattar, N.; Cantin, B.; Lamarche, B.; Després, J. P.; Wingard, D. L.; Daniels, L. B.; Gudnason, V.; Aspelund, T.; Trevisan, M.; Hofman, A.; Franco, O. H.; Tunstall-Pedoe, H.; Tavendale, R.; Lowe, G. D O; Woodward, M.; Howard, W. J.; Howard, B. V.; Zhang, Y.; Best, L. G.; Umans, J.; Ben-Shlomo, Y.; Davey-Smith, G.; Onat, A.; Nakagawa, H.; Sakurai, M.; Nakamura, K.; Morikawa, Y.; Njølstad, I.; Mathiesen, E. B.; Wilsgaard, T.; Sundström, J.; Gaziano, J. M.; Ridker, P. M.; Marmot, M.; Clarke, R.; Collins, R.; Fletcher, A.; Brunner, E.; Shipley, M.; Kivimaki, M.; Ridker, P. M.; Buring, J.; Rifai, N.; Cook, N.; Ford, I.; Robertson, M.; Marín Ibañez, A.; Feskens, E. J M; Geleijnse, J. M.

    2015-01-01

    Motivation: Discrimination statistics describe the ability of a survival model to assign higher risks to individuals who experience earlier events: examples are Harrell's C-index and Royston and Sauerbrei's D, which we call the D-index. Prognostic covariates whose distributions are controlled by the

  16. Efficient retrieval of landscape Hessian: forced optimal covariance adaptive learning.

    Science.gov (United States)

    Shir, Ofer M; Roslund, Jonathan; Whitley, Darrell; Rabitz, Herschel

    2014-06-01

    Knowledge of the Hessian matrix at the landscape optimum of a controlled physical observable offers valuable information about the system robustness to control noise. The Hessian can also assist in physical landscape characterization, which is of particular interest in quantum system control experiments. The recently developed landscape theoretical analysis motivated the compilation of an automated method to learn the Hessian matrix about the global optimum without derivative measurements from noisy data. The current study introduces the forced optimal covariance adaptive learning (FOCAL) technique for this purpose. FOCAL relies on the covariance matrix adaptation evolution strategy (CMA-ES) that exploits covariance information amongst the control variables by means of principal component analysis. The FOCAL technique is designed to operate with experimental optimization, generally involving continuous high-dimensional search landscapes (≳30) with large Hessian condition numbers (≳10^{4}). This paper introduces the theoretical foundations of the inverse relationship between the covariance learned by the evolution strategy and the actual Hessian matrix of the landscape. FOCAL is presented and demonstrated to retrieve the Hessian matrix with high fidelity on both model landscapes and quantum control experiments, which are observed to possess nonseparable, nonquadratic search landscapes. The recovered Hessian forms were corroborated by physical knowledge of the systems. The implications of FOCAL extend beyond the investigated studies to potentially cover other physically motivated multivariate landscapes.

  17. Covariance matrices for use in criticality safety predictability studies

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H.; Larson, N.M.; Leal, L.C.

    1997-09-01

    Criticality predictability applications require as input the best available information on fissile and other nuclides. In recent years important work has been performed in the analysis of neutron transmission and cross-section data for fissile nuclei in the resonance region by using the computer code SAMMY. The code uses Bayes method (a form of generalized least squares) for sequential analyses of several sets of experimental data. Values for Reich-Moore resonance parameters, their covariances, and the derivatives with respect to the adjusted parameters (data sensitivities) are obtained. In general, the parameter file contains several thousand values and the dimension of the covariance matrices is correspondingly large. These matrices are not reported in the current evaluated data files due to their large dimensions and to the inadequacy of the file formats. The present work has two goals: the first is to calculate the covariances of group-averaged cross sections from the covariance files generated by SAMMY, because these can be more readily utilized in criticality predictability calculations. The second goal is to propose a more practical interface between SAMMY and the evaluated files. Examples are given for {sup 235}U in the popular 199- and 238-group structures, using the latest ORNL evaluation of the {sup 235}U resonance parameters.

  18. Covariance, correlation matrix, and the multiscale community structure of networks.

    Science.gov (United States)

    Shen, Hua-Wei; Cheng, Xue-Qi; Fang, Bin-Xing

    2010-07-01

    Empirical studies show that real world networks often exhibit multiple scales of topological descriptions. However, it is still an open problem how to identify the intrinsic multiple scales of networks. In this paper, we consider detecting the multiscale community structure of network from the perspective of dimension reduction. According to this perspective, a covariance matrix of network is defined to uncover the multiscale community structure through the translation and rotation transformations. It is proved that the covariance matrix is the unbiased version of the well-known modularity matrix. We then point out that the translation and rotation transformations fail to deal with the heterogeneous network, which is very common in nature and society. To address this problem, a correlation matrix is proposed through introducing the rescaling transformation into the covariance matrix. Extensive tests on real world and artificial networks demonstrate that the correlation matrix significantly outperforms the covariance matrix, identically the modularity matrix, as regards identifying the multiscale community structure of network. This work provides a novel perspective to the identification of community structure and thus various dimension reduction methods might be used for the identification of community structure. Through introducing the correlation matrix, we further conclude that the rescaling transformation is crucial to identify the multiscale community structure of network, as well as the translation and rotation transformations.

  19. Source Coding in Networks with Covariance Distortion Constraints

    DEFF Research Database (Denmark)

    Zahedi, Adel; Østergaard, Jan; Jensen, Søren Holdt;

    2016-01-01

    We consider a source coding problem with a network scenario in mind, and formulate it as a remote vector Gaussian Wyner-Ziv problem under covariance matrix distortions. We define a notion of minimum for two positive-definite matrices based on which we derive an explicit formula for the rate...

  20. Experimental Uncertainty and Covariance Information in EXFOR Library

    Directory of Open Access Journals (Sweden)

    Schillebeeckx P.

    2012-05-01

    Full Text Available Compilation of experimental uncertainty and covariance information in the EXFOR Library is discussed. Following the presentation of a brief history of information provided in the EXFOR Library, the current EXFOR Formats and their limitations are reviewed. Proposed extensions for neutron-induced reaction cross sections in the fast neutron region and resonance region are also presented.

  1. A Superfield Formalism of osp(1,2) Covariant Quantization

    CERN Document Server

    Lavrov, P M

    2001-01-01

    We propose a superfield description of osp(1,2) covariant quantization by extending the set of admissibility conditions for the quantum action. We realize a superfield form of the generating equations, specify the vacuum functional and obtain the corresponding transformations of extended BRST symmetry.

  2. Equivalence between the Covariant and Bardeen Perturbation Formalisms

    CERN Document Server

    Vitenti, S D P; Pinto-Neto, N

    2013-01-01

    In a previous work we obtained a set of necessary conditions for the linear approximation in cosmology. Here we discuss the relations of this approach with the so called covariant perturbations. It is often argued in the literature that one of the main advantages of the covariant approach to describe the cosmological perturbations is that the Bardeen formalism is coordinate dependent. In this paper we will reformulate the Bardeen approach in a completely covariant manner. For that, we introduce the notion of pure and mixed tensors that yields an adequate language to treat both perturbative approaches in a common framework. Additionally, we define full non-linear tensors that at first order correspond to the three known gauge invariant variables $\\Phi$, $\\Psi$ and $\\Xi$. We also stress that in the referred covariant approach one necessarily introduces an additional hyper-surface choice to the problem, and the same tensor combinations above at first order are also hyper-surface invariant making the gauge invari...

  3. Hawking Radiation from Plane Symmetric Black Hole Covariant Anomaly

    Institute of Scientific and Technical Information of China (English)

    ZENG Xiao-Xiong; HAN Yi-Wen; YANG Shu-Zheng

    2009-01-01

    Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result shows that Hawking radiation from the non-spherical symmetric black holes also can be derived from the viewpoint of anomaly.

  4. Treatment decisions based on scalar and functional baseline covariates.

    Science.gov (United States)

    Ciarleglio, Adam; Petkova, Eva; Ogden, R Todd; Tarpey, Thaddeus

    2015-12-01

    The amount and complexity of patient-level data being collected in randomized-controlled trials offer both opportunities and challenges for developing personalized rules for assigning treatment for a given disease or ailment. For example, trials examining treatments for major depressive disorder are not only collecting typical baseline data such as age, gender, or scores on various tests, but also data that measure the structure and function of the brain such as images from magnetic resonance imaging (MRI), functional MRI (fMRI), or electroencephalography (EEG). These latter types of data have an inherent structure and may be considered as functional data. We propose an approach that uses baseline covariates, both scalars and functions, to aid in the selection of an optimal treatment. In addition to providing information on which treatment should be selected for a new patient, the estimated regime has the potential to provide insight into the relationship between treatment response and the set of baseline covariates. Our approach can be viewed as an extension of "advantage learning" to include both scalar and functional covariates. We describe our method and how to implement it using existing software. Empirical performance of our method is evaluated with simulated data in a variety of settings and also applied to data arising from a study of patients with major depressive disorder from whom baseline scalar covariates as well as functional data from EEG are available.

  5. Unified Approach to Universal Cloning and Phase-Covariant Cloning

    OpenAIRE

    Hu, Jia-Zhong; Yu, Zong-Wen; Wang, Xiang-Bin

    2008-01-01

    We analyze the problem of approximate quantum cloning when the quantum state is between two latitudes on the Bloch's sphere. We present an analytical formula for the optimized 1-to-2 cloning. The formula unifies the universal quantum cloning (UQCM) and the phase covariant quantum cloning.

  6. A New Test for a Normal Covariance Matrix

    Institute of Scientific and Technical Information of China (English)

    禹建奇

    2015-01-01

    The problem of testing the normal covariance matrix equal to a specified matrix is considered.A new Chi-Square test statistic is derived for multivariate normal population.Unlike the likelihood ratio test,the new test is an exact one.

  7. Covariation of Color and Luminance Facilitate Object Individuation in Infancy

    Science.gov (United States)

    Woods, Rebecca J.; Wilcox, Teresa

    2010-01-01

    The ability to individuate objects is one of our most fundamental cognitive capacities. Recent research has revealed that when objects vary in color or luminance alone, infants fail to individuate those objects until 11.5 months. However, color and luminance frequently covary in the natural environment, thus providing a more salient and reliable…

  8. Effect on Prediction when Modeling Covariates in Bayesian Nonparametric Models.

    Science.gov (United States)

    Cruz-Marcelo, Alejandro; Rosner, Gary L; Müller, Peter; Stewart, Clinton F

    2013-04-01

    In biomedical research, it is often of interest to characterize biologic processes giving rise to observations and to make predictions of future observations. Bayesian nonparametric methods provide a means for carrying out Bayesian inference making as few assumptions about restrictive parametric models as possible. There are several proposals in the literature for extending Bayesian nonparametric models to include dependence on covariates. Limited attention, however, has been directed to the following two aspects. In this article, we examine the effect on fitting and predictive performance of incorporating covariates in a class of Bayesian nonparametric models by one of two primary ways: either in the weights or in the locations of a discrete random probability measure. We show that different strategies for incorporating continuous covariates in Bayesian nonparametric models can result in big differences when used for prediction, even though they lead to otherwise similar posterior inferences. When one needs the predictive density, as in optimal design, and this density is a mixture, it is better to make the weights depend on the covariates. We demonstrate these points via a simulated data example and in an application in which one wants to determine the optimal dose of an anticancer drug used in pediatric oncology.

  9. Is Homo sapiens polytypic? Human taxonomic diversity and its implications.

    Science.gov (United States)

    Woodley, Michael A

    2010-01-01

    The term race is a traditional synonym for subspecies, however it is frequently asserted that Homo sapiens is monotypic and that what are termed races are nothing more than biological illusions. In this manuscript a case is made for the hypothesis that H. sapiens is polytypic, and in this way is no different from other species exhibiting similar levels of genetic and morphological diversity. First it is demonstrated that the four major definitions of race/subspecies can be shown to be synonymous within the context of the framework of race as a correlation structure of traits. Next the issue of taxonomic classification is considered where it is demonstrated that H. sapiens possesses high levels morphological diversity, genetic heterozygosity and differentiation (F(ST)) compared to many species that are acknowledged to be polytypic with respect to subspecies. Racial variation is then evaluated in light of the phylogenetic species concept, where it is suggested that the least inclusive monophyletic units exist below the level of species within H. sapiens indicating the existence of a number of potential human phylogenetic species; and the biological species concept, where it is determined that racial variation is too small to represent differentiation at the level of biological species. Finally the implications of this are discussed in the context of anthropology where an accurate picture of the sequence and timing of events during the evolution of human taxa are required for a complete picture of human evolution, and medicine, where a greater appreciation of the role played by human taxonomic differences in disease susceptibility and treatment responsiveness will save lives in the future.

  10. Some asymptotic properties of kriging when the covariance function is misspecified

    Energy Technology Data Exchange (ETDEWEB)

    Stein, M.L.; Handcock, M.S.

    1989-02-01

    The impact of using an incorrect covariance function of kriging predictors is investigated. Results of Stein (1988) show that the impact on the kriging predictor from not using the correct covariance function is asymptotically negligible as the number of observations increases if the covariance function used is compatible with the actual covariance function on the region of interest R. The definition and some properties of compatibility of covariance functions are given. The compatibility of generalized covariances also is defined. Compatibility supports the intuitively sensible concept that usually only the behavior near the origin of the covariance function is critical for purposes of kriging. However, the commonly used spherical covariance function is an exception: observations at a distance near the range of a spherical covariance function can have a nonnegligible effect on kriging predictors for three-dimensional processes. Finally, a comparison is made with the perturbation approach of Diamond and Armstrong (1984) and some observations of Warnes (1986) are clarified.

  11. Genetic composition of Mytilus species in mussel populations from southern Chile Composición genética de especies de Mytilus en poblaciones de mejillón del sur de Chile

    Directory of Open Access Journals (Sweden)

    María Angélica Larraín

    2012-11-01

    Full Text Available Mussels are one of the most cultivated and commercialized bivalves worldwide and in southern Chile its culture represent an important economic activity. The species identification within the Mytilus genera, by morphological features, is unreliable, so we used a polymorphism RFLP in the gene encoding the polyphenolic adhesive protein as a species-specific genetic marker to describe Mytilus species diversity in southern Chile, and evaluate possible applications in traceability, food quality and safety. Using Me 15-16 marker most mussels were M. chilensis, finding no other pure individuals; however, putative hybrids of M. chilensis x M. trossulus and M. chilensis x M. galloprovincialis were detected. There was no evidence of M. edulis. The presence of the M. trossulus allele, faraway from its distribution area, demands further analysis with different genetic markers to allow a better understanding of its origin. In addition, the correspondence between markers that distinguishes northern from southern hemisphere M. galloprovincialis, with those who discriminates between M. chilensis and M. galloprovincialis would contribute to the taxonomic status of Chilean blue mussels. In Chile, the genetic composition of Mytilus indicates that geographical origin of mussels and its traceability cannot be established merely from the identification of the species. The use of other markers would be required.Los mejillones son una de las especies de bivalvos más cultivadas y comercializadas, en el sur de Chile donde su cultivo representa una actividad económica importante. La identificación de la especie dentro del género Mytilus, basada en las características morfológicas no es confiable por lo que se utilizó un polimorfismo RFLP en el gen que codifica la proteína adhesiva polifenólica como marcador genético específico de la especie para describir la diversidad de especies Mytilus en el sur de Chile, y evaluar posibles aplicaciones en trazabilidad

  12. La Medialuna: un edificio para Chile/The Crescent, a building for Chile

    Directory of Open Access Journals (Sweden)

    Moreira Recchione, Alberto

    2007-12-01

    Full Text Available Se refiere los antecedentes históricos sobre la escuela ecuestre de la jineta y su introducción en las faenas agrícola-ganaderas chilenas. Se reseña el nacimiento del rodeo como deporte nacional chileno y los requerimientos del complejo espacio de la “fiesta del rodeo”: un problema arquitectónico y también urbanístico./ The equestrian school of "La Jineta" in Chile, and the architecture for the national holiday of "rodeo."

  13. Assessing spatial covariance among time series of abundance.

    Science.gov (United States)

    Jorgensen, Jeffrey C; Ward, Eric J; Scheuerell, Mark D; Zabel, Richard W

    2016-04-01

    For species of conservation concern, an essential part of the recovery planning process is identifying discrete population units and their location with respect to one another. A common feature among geographically proximate populations is that the number of organisms tends to covary through time as a consequence of similar responses to exogenous influences. In turn, high covariation among populations can threaten the persistence of the larger metapopulation. Historically, explorations of the covariance in population size of species with many (>10) time series have been computationally difficult. Here, we illustrate how dynamic factor analysis (DFA) can be used to characterize diversity among time series of population abundances and the degree to which all populations can be represented by a few common signals. Our application focuses on anadromous Chinook salmon (Oncorhynchus tshawytscha), a species listed under the US Endangered Species Act, that is impacted by a variety of natural and anthropogenic factors. Specifically, we fit DFA models to 24 time series of population abundance and used model selection to identify the minimum number of latent variables that explained the most temporal variation after accounting for the effects of environmental covariates. We found support for grouping the time series according to 5 common latent variables. The top model included two covariates: the Pacific Decadal Oscillation in spring and summer. The assignment of populations to the latent variables matched the currently established population structure at a broad spatial scale. At a finer scale, there was more population grouping complexity. Some relatively distant populations were grouped together, and some relatively close populations - considered to be more aligned with each other - were more associated with populations further away. These coarse- and fine-grained examinations of spatial structure are important because they reveal different structural patterns not evident

  14. Residual noise covariance for Planck low-resolution data analysis

    Science.gov (United States)

    Keskitalo, R.; Ashdown, M. A. J.; Cabella, P.; Kisner, T.; Poutanen, T.; Stompor, R.; Bartlett, J. G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; de Rosa, A.; de Troia, G.; Eriksen, H. K.; Finelli, F.; Górski, K. M.; Gruppuso, A.; Hivon, E.; Jaffe, A.; Keihänen, E.; Kurki-Suonio, H.; Lawrence, C. R.; Natoli, P.; Paci, F.; Polenta, G.; Rocha, G.

    2010-11-01

    Aims: We develop and validate tools for estimating residual noise covariance in Planck frequency maps, we also quantify signal error effects and compare different techniques to produce low-resolution maps. Methods: We derived analytical estimates of covariance of the residual noise contained in low-resolution maps produced using a number of mapmaking approaches. We tested these analytical predictions using both Monte Carlo simulations and by applying them to angular power spectrum estimation. We used simulations to quantify the level of signal errors incurred in the different resolution downgrading schemes considered in this work. Results: We find excellent agreement between the optimal residual noise covariance matrices and Monte Carlo noise maps. For destriping mapmakers, the extent of agreement is dictated by the knee frequency of the correlated noise component and the chosen baseline offset length. Signal striping is shown to be insignificant when properly dealt with. In map resolution downgrading, we find that a carefully selected window function is required to reduce aliasing to the subpercent level at multipoles, ℓ > 2Nside, where Nside is the HEALPix resolution parameter. We show that, for a polarization measurement, reliable characterization of the residual noise is required to draw reliable constraints on large-scale anisotropy. Conclusions: Methods presented and tested in this paper allow for production of low-resolution maps with both controlled sky signal error level and a reliable estimate of covariance of the residual noise. We have also presented a method for smoothing the residual noise covariance matrices to describe the noise correlations in smoothed, bandwidth-limited maps.

  15. Taxonomic history and invasion biology of two Phyllonorycter leaf miners (Lepidoptera: Gracillariidae) with links to taxonomic and molecular datasets.

    Science.gov (United States)

    De Prins, Jurate; De Prins, Willy; De Coninck, Eliane; Kawahara, Akito Y; Milton, Megan A; Hebert, Paul D N

    2013-01-01

    This paper deals with two European species, Phyllonorycter mespilella (Hübner, 1805) and P. trifasciella (Haworth, 1828), that have colonized the subtropical Canary Islands. The Rosaceae leaf miner, P. mespilella, is recorded for the first time from Lanzarote and La Palma, while the Caprifoliaceae leaf miner, P. trifasciella, is recorded from Tenerife. We present the diagnoses of these species based on morphology, a preliminary DNA barcode (COI) library of congeneric and con-familial species, and discuss the taxonomic position of the colonizers within the blancardella and trifasciella species groups. The recent intensification of anthropogenic disturbance likely accounts for their range expansion, an event that may impact the relict flora present on the Canary Islands.

  16. Taxonomic Organization Scaffolds Young Children's Learning from Storybooks: A Design Experiment

    Science.gov (United States)

    Kaefer, Tanya; Pinkham, Ashley M.; Neuman, Susan B.

    2010-01-01

    The purpose of this design experiment was to research, test and iteratively design a set of taxonomically-organized storybooks that served to scaffold young children's word learning and concept development. Specifically, Phase 1 of the design experiment asked: (1) What are the effects of taxonomic organization on children's ability to acquire…

  17. Taxonomic and ecological notes on Buenia affinis Iljin 1930 (Pisces: Gobiidae)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, F.; Giacobbe, S.; Salpietro, L. [S. Agata, Messina, Univ. (Italy). Facolta` di Scienze. Dipt. di Biologia Animale ed Ecologia Marina

    1996-12-31

    Taxonomic and ecological notes on Buenia affinis Iljin 1930 (Pisces: Gobiidae). A population of the rare Teleost Buenia affinis Iljin 1930 has been sampled in a brackish pool along the Sicilian Tyrrhenic coastline. A description of the taxonomic features as well as first observations on the ecology of the species are given in detail.

  18. NODC Standard Product: NODC Taxonomic Code on CD-ROM (NODC Accession 0050418)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The content of the NODC Taxonomic Code, Version 8 CD-ROM (CD-ROM NODC-68) distributed by NODC is archived in this accession. Version 7 of the NODC Taxonomic Code...

  19. Taxonomic status of the roses (Rosa) described by S.G. Dimitrov from Bulgaria

    DEFF Research Database (Denmark)

    Zielinski, J.; Petrova, A; Tan, Kit

    2004-01-01

    The original herbarium vouchers for six species of Rosa (Rosaceae) described by S. G. Dimitrov from Bulgaria are taxonomically evaluated. Two species (R. balcanica, R. orphei) are considered hybrids, four other names (R. bulgarica, R. parilica, R. pontica and R. rhodopaea) are taxonomic synonyms...

  20. Polysemy and the Taxonomic Constraint: Children's Representation of Words That Label Multiple Kinds

    Science.gov (United States)

    Srinivasan, Mahesh; Snedeker, Jesse

    2014-01-01

    How do children resolve the problem of indeterminacy when learning a new word? By one account, children adopt a "taxonomic assumption" and expect the word to denote only members of a particular taxonomic category. According to one version of this constraint, young children should represent polysemous words that label multiple kinds--for…

  1. Social Networks and Political Parties in Chile

    Directory of Open Access Journals (Sweden)

    Adler Lomnitz, Larissa

    2002-09-01

    Full Text Available This paper describes the origin and evolution of two Chilean political parties (the Radical Party and the Christian Democrat Party through the analysis of the social networks that originated and composed them. The aim of this study is to propose a model of national political cultures on the basis of the structure of social networks related to power and of the symbol system, which legitimizes it. The structure of social networks, horizontal and vertical, are based on reciprocal or redistributive forms of exchange, on what is being exchanged and on the articulation between networks. In every society there are symmetrical and asymmetrical exchanges, which produce horizontal and vertical networks. These networks interact among themselves to form the social fabric. The dominance of some over others and how they combine, delineate the character of the political culture (authoritarian vs. egalitarian. Chile is a multiparty country within which there are cohorts of horizontal groups of friends, who informally exercise a central control over their members and create invisible boundaries setting them apart from others, in which leadership is under constrains. The result is both a strong presidential system based on an almost fanatic legitimacy, combined with factionalism and a strong parliamentary system.

  2. Macroeconomic fluctuations and bank behavior in Chile

    Directory of Open Access Journals (Sweden)

    Jorge E. Restrepo

    2008-03-01

    Full Text Available The purpose of this study is to analyze bank behavior in Chile over time, looking at how their balance sheets and performance move both in the short and long run, and how they react to macroeconomic shocks. The evolution of banking aggregates over an 18 year period (1989-2006, using quarterly data is examined. Techniques common in the real business cycle literature are applied to establish empirical patterns. Robustness tests using several filters are performed. The effects of macro shocks on banking variables are analyzed, both by means of an event study, and by estimating impulse responses with VARs. The results show that credit lags the cycle, demand deposits lead it, both being procyclical, while the capital adequacy ratio (CAR is countercyclical. In addition, a shock to interest rates reduces loans (total, commercial, consumption, and increases non performing loans (NPL and the capital adequacy ratio (CAR. A shock to GDP growth has a positive effect on loans, return over equity (ROE, and a negative impact on NPL and CAR.

  3. Financiamiento Solidario para Vivienda en Chile

    Directory of Open Access Journals (Sweden)

    Mauricio Rojas Mujica

    2007-01-01

    Full Text Available El Programa de Desarrollo Solidario (PDS del Banco del Desarrollo consiste en brindar apoyo financiero y formativo a mujeres de escasos recursos a lo largo de todo Chile, a través de un crédito solidario, sin ningún otro tipo de garantía que la confianza, la responsabilidad y la solidaridad. En este Programa se trabaja con grupos de al menos 8 mujeres de muy escasos recursos que no tienen acceso al sistema bancario tradicional por no contar con ingresos demostrables ni estables. El apoyo financiero se canaliza a través de créditos solidarios. El apoyo formativo consiste en un trabajo en forma previa al otorgamiento de los créditos y luego un seguimiento periódico del grupo, durante todo el periodo de reembolso del crédito. A la fecha, han participado en este programa más de 10.000 mujeres, estimándose que más de 6.000 de ellas han dedicado estos préstamos al mejoramiento de la calidad de su vivienda, movilizando en forma directa más de 2 millones de dólares.

  4. [Nutritive value of shellfish consumed in Chile].

    Science.gov (United States)

    Pak, N; Vera, G; Araya, H

    1985-03-01

    The purpose of the present study was to determine the protein quality and digestibility of shellfish commonly consumed in Chile, and to estimate its contribution to the protein needs of the Chilean population. The shellfish studied were chorito (Mytilus edulis chilensis), macha (Mesodesma donacium), loco (Concholepas concholepas), cholga (Aulacomya ater), erizo (Loxechinus albus) and almeja (no specific variety). The NPU method was used to determine protein quality. The percentage of protein adequacy for adult rations was calculated according to FAO/WHO 1973. The contribution of shellfish to the protein availability according to the family income of the Santiago population, was also calculated. Most of the shellfish presented NPU values of about 70; the lowest values were found for loco (54.9) and macha (63.3). The apparent and true digestibility gave an average of 83.6 and 90.4, respectively. The percentage of protein adequacy of habitual rations ranged between 27% (erizo) and 58% (loco). The availability of shellfish protein in relation to total protein increased from 0.4 to 2.5% when income increased. It is concluded therefore, that shellfish protein is, in general, of good quality. Nevertheless, it might be considered of poor influence insofar as fulfilling the protein needs of the population studied, whatever its socioeconomic level.

  5. Selective extinction drives taxonomic and functional alpha and beta diversities in island bird assemblages.

    Science.gov (United States)

    Si, Xingfeng; Baselga, Andrés; Leprieur, Fabien; Song, Xiao; Ding, Ping

    2016-03-01

    Taxonomic diversity considers all species being equally different from each other and thus disregards species' different ecological functions. Exploring taxonomic and functional aspects of biodiversity simultaneously can better understand the processes of community assembly. We analysed taxonomic and functional alpha and beta diversities of breeding bird assemblages on land-bridge islands in the Thousand Island Lake, China. Given the high dispersal ability of most birds at this spatial scale (several kilometres), we predicted (i) selective extinction driving alpha and beta diversities after the creation of land-bridge islands of varying area and (ii) low taxonomic and functional beta diversities that were not correlated to spatial distance. Breeding birds were surveyed on 37 islands annually from 2007 to 2014. We decomposed beta diversity of breeding birds into spatial turnover and nestedness-resultant components, and related taxonomic and functional diversities to island area and isolation using power regression models (for alpha diversity) and multiple regression models on distance matrices (for beta diversity). We then ran simulations to assess the strength of the correlations between taxonomic and functional diversities. Results revealed that both taxonomic and functional alpha diversities increased with island area. The taxonomic nestedness-resultant and turnover components increased and decreased with difference in area, respectively, but functional counterparts did not. Isolation played a minor role in explaining alpha- and beta-diversity patterns. By partitioning beta diversity, we found low levels of overall taxonomic and functional beta diversities. The functional nestedness-resultant component dominated overall functional beta diversity, whereas taxonomic turnover was the dominant component for taxonomic beta diversity. The simulation showed that functional alpha and beta diversities were significantly correlated with taxonomic diversities, and the

  6. Taxonomía de Pacientes con Diabetes Tipo 2 Basada en sus Representaciones de Enfermedad Taxonomy of Patients With Type 2 Diabetes Based on Their Illness Representations

    Directory of Open Access Journals (Sweden)

    Constanza J Letelier

    2011-11-01

    Full Text Available Se estableció una taxonomía de personas con diabetes tipo 2 basada en sus representaciones de enfermedad. Para ello se realizó un análisis de conglomerados con las respuestas de una muestra de conveniencia de 103 adultos de atención primaria de salud de la zona central de Chile, los que completaron la escala IPQ-R. Este análisis arrojó 3 grupos de pacientes, denominados Preocupado, Desesperanzado y Negador. El primero confía en los procedimientos para atenuar los efectos de la enfermedad. El segundo manifiesta una baja creencia acerca de la posibilidad de controlarla. El tercero no la considera como una enfermedad crónica. Los grupos fueron comparados en respuesta emocional, intención de adherir, percepción de necesidad y preocupación por el tratamiento, para complementar el procedimiento de análisis de conglomerado, utilizando ANOVA o Chi cuadrado. Consistente con sus perfiles, presentan diferencias significativas en sus respuestas emocionales, creencias acerca de los medicamentos, intención de adherir, tiempo de tratamiento, edad y educación. Se discute la utilidad de estas taxonomías para el tratamiento diferencial de los pacientes.A taxonomy of patients with type 2 diabetes based on their illness representations was developed. To do this a cluster analysis was conducted, using the responses of a convenience sample of 103 adults from primary health care in central Chile, who completed the IPQ-R scale. This analysis lead to 3 groups of patients labeled Preoccupied, Hopeless, and Deniers. The first relies on procedures to mitigate the effects of the disease. The second shows a low belief about the possibility to control the disease. The third does not consider diabetes as a chronic disease. The groups were compared on emotional response, intention to adhere, perception of need and concern about the treatment, to complement the cluster analysis procedure, using ANOVA or chi-square. Consistent with their profiles, the groups

  7. Geographic variation in diversity of wave exposed rocky intertidal communities along central Chile Variación geográfica de la biodiversidad en hábitats intermareales rocosos de Chile central

    Directory of Open Access Journals (Sweden)

    BERNARDO R BROITMAN

    2011-03-01

    Full Text Available Along the coast of central Chile, geographic trends of diversity have been inferred from literature compilations and museum collections based on species range limits for some taxonomic groups. However, spatially-intensive field-based assessments of macrobenthic species richness are largely missing. Over the course of a multiyear study (1998-2005, we characterized latitudinal patterns of rocky intertidal diversity at 18 sites along the coast of central Chile (29-36° S. At each site, the number of sessile and mobile macrobenthic species was quantified in 0.25 m² quadrats. Two estimators of local (alpha diversity were used: observed local species richness, calculated from the asymptote of a species-rarefaction curve, and the Chao2 index, which takes into account the effect of rare species on estimates of local richness. We identified a total of 71 species belonging to 66 genera for a total of 86 taxa. The most diverse groups were herbivorous mollusks (27 taxa and macroalgae (43 taxa. Diversity showed a complex spatial pattern with areas of high species richness interspersed with areas of low richness. In accordance with previous work, we found no trend in the number of herbivorous mollusks and an inverse and significant latitudinal gradient in the number of algal species. Our results highlight the need for taxonomically diverse assessments of biodiversity of the dominant taxa that conform intertidal communities.A lo largo de la costa de Chile central, los patrones geográficos de diversidad han sido inferidos a partir de revisiones literarias y colecciones de museos para algunos grupos taxonómicos. Sin embargo, aun no contamos con una evaluación integral, y en terreno, de la riqueza de especies macrobentónicas intermareales. En un estudio de largo plazo conducido entre 1998 y 2005 caracterizamos los patrones latitudinales en la biodiversidad del intermareal rocoso en 18 sitios a lo largo de la costa de Chile central (29-36° S. En cada sitio

  8. [Mental health in Chile and Finland: Challenges and lessons].

    Science.gov (United States)

    Retamal C, Pedro; Markkula, Niina; Peña, Sebastián

    2016-07-01

    This article analyses and compares the epidemiology of mental disorders and relevant public policies in Chile and Finland. In Chile, a specific mental health law is still lacking. While both countries highlight the role of primary care, Finland places more emphasis on participation and recovery of service users. Comprehensive mental health policies from Finland, such as a successful suicide prevention program, are presented. Both countries have similar prevalence of mental disorders, high alcohol consumption and high suicide rates. In Chile, the percentage of total disease burden due to psychiatric disorders is 13% and in Finland 14%. However, the resources to address these issues are very different. Finland spends 4.5% of its health budget on mental health, while in Chile the percentage is 2.2%. This results in differences in human resources and service provision. Finland has five times more psychiatric outpatient visits, four times more psychiatrists, triple antidepressant use and twice more clinical guidelines for different psychiatric conditions. In conclusion, both countries have similar challenges but differing realities. This may help to identify gaps and potential solutions for public health challenges in Chile. Finland’s experience demonstrates the importance of political will and long-term vision in the construction of mental health policies.

  9. [The evolution theory in the medical sciences in Chile].

    Science.gov (United States)

    Cruz-Coke, R

    1994-02-01

    The evolutionist ideas of Lamarck, Darwin and Haeckel entered the country through the arrival of their books. "On the origin of Species" arrived in Chile in 1869. The most outstanding immigrant european physicians that discussed these ideas were Rodulfo A Phillippi (1808-1904) and Juan José Brunner (1825-1899). Both discussed Darwin's ideas in their books and conferences as academics of the Faculty of Medicine of the University of Chile. The first Chilean physicians that read and discussed the validity of evolution theory were Adolfo Valderrama (1834-1902) and Pedro Candia Salgado. Both wrote articles about this matter in Revista Médica de Chile in 1872 and 1874. The professor of general biology, Juan Noé Crevani, italian physician and zoologist that arrived in Chile in 1912, was the first to teach directly the concepts of the evolution theory until his death in 1947. Professor Noé founded the great biological school of the twentieth century in Chile and his disciples introduced the concepts of Mendelian theory and neodarwinism in the decade of fifties. The theory of evolution was taught as a chapter of general biology in the Faculty of Medicine between 1913 and 1947, but its practical applications to medicine were introduced with the birth of medical genetics in the decade of fifties and the foundation of Chilean Genetics society in 1964, under the direction of professors Danko Brncic and Gustavo Hoecker, both awarded with the National Sciences Prize.

  10. Anseriform brain and its parts versus taxonomic and ecological categories.

    Science.gov (United States)

    Kalisińska, Elzbieta

    2005-01-01

    The size of the brain and its macro-anatomical parts in 206 birds representing 19 anseriform species and 4 tribes (Anserini, Anatini, Aythyini and Mergini) was the subject of a comparative analysis. The comparisons involved two aspects: taxonomic (differences among species within tribes and differences among tribes) and ecological (diet composition: vegetation, invertebrates, or fish and the foraging mode: browsing, dabbling, shallow diving, and deep diving). The relative size of the encephalon (E) and its parts (optic tectum, OT; cerebellum, C; brain stem, BS; hemispheres, H) were described using appropriate indices. Five of them, called the cerebral-body indices (E/BW, OT/BW, C/BW, BS/BW, H/BW), involved a ratio between the weight of E or its parts and that of the body (BW). Four intracerebral indices (OT/E, C/E, BS/E, H/E) and allometric equations were used as well. Almost all the indices showed a high intraspecific variability within the Anserini and Mergini; on the other hand, the intracerebral indices did not differ between the species of the Anatini and Aythyini (except for OT/E in the Aythyini). Between-tribe differences were reflected in all 9 indices. The birds feeding on different diets were found to differ in their OT/E and H/E. The herbivorous anserifom OT/E was clearly lower than that of those birds feeding on invertebrates and fish. The highest OT/E was that of the piscivorous birds. In terms of foraging mode, significant differences were revealed in 7 out of the 9 indices used (differences in OT/BW and C/BW proved non-significant). OT/E of the browsing birds was clearly lower than that of the deep diving ducks; BS/E of the browsers was much lower than that of the dabbling and shallow diving ducks. Geese and swans (browsers) showed much higher H/E compared to the deep diving sea ducks. The latter revealed the highest C/E, but significant differences were detected only in comparison with C/E of the shallow diving ducks. The taxonomic (among tribes

  11. 75 FR 19658 - Preserved Mushrooms From Chile, China, India, and Indonesia; Determinations

    Science.gov (United States)

    2010-04-15

    ... (Second Review)] Preserved Mushrooms From Chile, China, India, and Indonesia; Determinations On the basis...)), that revocation of the antidumping duty orders on preserved mushrooms from Chile, China, India, and... (April 2010), entitled Preserved Mushrooms from Chile, China, India, and Indonesia: Investigation...

  12. 76 FR 65933 - Importation of Fresh Baby Kiwi From Chile Under a Systems Approach

    Science.gov (United States)

    2011-10-25

    ... Health Inspection Service 7 CFR Part 319 RIN 0579-AD37 Importation of Fresh Baby Kiwi From Chile Under a... United States of baby kiwi fruit from Chile, subject to a systems approach. Under this systems approach... baby kiwi from Chile using mitigation measures other than fumigation with methyl bromide....

  13. 75 FR 32901 - Notice of Determination of Pest-Free Areas in the Republic of Chile

    Science.gov (United States)

    2010-06-10

    ... Chile AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Notice. SUMMARY: We are advising the public that we are recognizing an additional area of the Republic of Chile as a pest-free area for... the documentation submitted by the Republic of Chile, which we made available to the public review...

  14. CHILE: An Evidence-Based Preschool Intervention for Obesity Prevention in Head Start

    Science.gov (United States)

    Davis, Sally M.; Sanders, Sarah G.; FitzGerald, Courtney A.; Keane, Patricia C.; Canaca, Glenda F.; Volker-Rector, Renee

    2013-01-01

    Background: Obesity is a major concern among American Indians and Hispanics. The Child Health Initiative for Lifelong Eating and Exercise (CHILE) is an evidence-based intervention to prevent obesity in children enrolled in 16 Head Start (HS) Centers in rural communities. The design and implementation of CHILE are described. Methods: CHILE uses a…

  15. 7 CFR 319.56-23 - Apricots, nectarines, peaches, plumcot, and plums from Chile.

    Science.gov (United States)

    2010-01-01

    ... Chile. 319.56-23 Section 319.56-23 Agriculture Regulations of the Department of Agriculture (Continued... and Vegetables § 319.56-23 Apricots, nectarines, peaches, plumcot, and plums from Chile. (a... from Chile in accordance with this section and all other applicable provisions of this subpart. 3 3...

  16. 19 CFR 10.490 - Goods re-entered after repair or alteration in Chile.

    Science.gov (United States)

    2010-04-01

    ... Chile. 10.490 Section 10.490 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... States-Chile Free Trade Agreement Goods Returned After Repair Or Alteration § 10.490 Goods re-entered after repair or alteration in Chile. (a) General. This section sets forth the rules which apply...

  17. 75 FR 22369 - Certain Preserved Mushrooms From Chile, India, Indonesia, and the People's Republic of China...

    Science.gov (United States)

    2010-04-28

    ... International Trade Administration Certain Preserved Mushrooms From Chile, India, Indonesia, and the People's... antidumping duty orders on certain preserved mushrooms (mushrooms) from Chile, India, Indonesia, and the... reviews of the antidumping duty orders on mushrooms from Chile, India, Indonesia, and the PRC, pursuant...

  18. 75 FR 3756 - Preserved Mushrooms from Chile, China, India, and Indonesia

    Science.gov (United States)

    2010-01-22

    ... TRADE COMMISSION Preserved Mushrooms from Chile, China, India, and Indonesia AGENCY: United States... duty orders on preserved mushrooms from Chile, China, India, and Indonesia. SUMMARY: The Commission... orders on preserved mushrooms from Chile, China, India, and Indonesia would be likely to lead...

  19. 77 FR 12903 - Suggestions for Environmental Cooperation Pursuant to the United States-Chile Environmental...

    Science.gov (United States)

    2012-03-02

    ... Suggestions for Environmental Cooperation Pursuant to the United States-Chile Environmental Cooperation Agreement ACTION: Notice of preparation of the 2012-2014 U.S.-Chile Environmental Cooperation Work Program... suggestions regarding items for inclusion in a new work program for implementing the U.S.-Chile...

  20. Global recoverable reserve estimation by covariance matching constrained kriging

    Energy Technology Data Exchange (ETDEWEB)

    Tercan, A.E. [Hacettepe University, Ankara (Turkey). Dept. of Mining Engineering

    2004-10-01

    A central problem in mining practice is estimation of global recoverable reserves, i.e., recovered tonnage and mean quality varying with cut-off value over the whole deposit. This article describes the application of covariance matching constrained kriging to the estimation of the global recoverable reserves in a lignite deposit in Turkey. Thickness and calorific value are the variables used in this study. The deposit is divided into 180 panels with 200 m x 200 m size and the mean calorific value of the panels is estimated by covariance matching constrained kriging. Quality tonnage curve is constructed based on the estimated mean values. For comparison, quality tonnage curve from ordinary kriging is also provided.

  1. Markov modulated Poisson process models incorporating covariates for rainfall intensity.

    Science.gov (United States)

    Thayakaran, R; Ramesh, N I

    2013-01-01

    Time series of rainfall bucket tip times at the Beaufort Park station, Bracknell, in the UK are modelled by a class of Markov modulated Poisson processes (MMPP) which may be thought of as a generalization of the Poisson process. Our main focus in this paper is to investigate the effects of including covariate information into the MMPP model framework on statistical properties. In particular, we look at three types of time-varying covariates namely temperature, sea level pressure, and relative humidity that are thought to be affecting the rainfall arrival process. Maximum likelihood estimation is used to obtain the parameter estimates, and likelihood ratio tests are employed in model comparison. Simulated data from the fitted model are used to make statistical inferences about the accumulated rainfall in the discrete time interval. Variability of the daily Poisson arrival rates is studied.

  2. Sparse Inverse Covariance Selection via Alternating Linearization Methods

    CERN Document Server

    Scheinberg, Katya; Goldfarb, Donald

    2010-01-01

    Gaussian graphical models are of great interest in statistical learning. Because the conditional independencies between different nodes correspond to zero entries in the inverse covariance matrix of the Gaussian distribution, one can learn the structure of the graph by estimating a sparse inverse covariance matrix from sample data, by solving a convex maximum likelihood problem with an $\\ell_1$-regularization term. In this paper, we propose a first-order method based on an alternating linearization technique that exploits the problem's special structure; in particular, the subproblems solved in each iteration have closed-form solutions. Moreover, our algorithm obtains an $\\epsilon$-optimal solution in $O(1/\\epsilon)$ iterations. Numerical experiments on both synthetic and real data from gene association networks show that a practical version of this algorithm outperforms other competitive algorithms.

  3. Estimating surface fluxes using eddy covariance and numerical ogive optimization

    DEFF Research Database (Denmark)

    Sievers, J.; Papakyriakou, T.; Larsen, Søren Ejling

    2015-01-01

    Estimating representative surface fluxes using eddy covariance leads invariably to questions concerning inclusion or exclusion of low-frequency flux contributions. For studies where fluxes are linked to local physical parameters and up-scaled through numerical modelling efforts, low-frequency con......Estimating representative surface fluxes using eddy covariance leads invariably to questions concerning inclusion or exclusion of low-frequency flux contributions. For studies where fluxes are linked to local physical parameters and up-scaled through numerical modelling efforts, low......-frequency contributions interfere with our ability to isolate local biogeochemical processes of interest, as represented by turbulent fluxes. No method currently exists to disentangle low-frequency contributions on flux estimates. Here, we present a novel comprehensive numerical scheme to identify and separate out low...

  4. Modeling corporate defaults: Poisson autoregressions with exogenous covariates (PARX)

    DEFF Research Database (Denmark)

    Agosto, Arianna; Cavaliere, Guiseppe; Kristensen, Dennis;

    in the analysis of the asympotic properties of the maximum-likelihood estimators of the models. The PARX class of models is used to analyse the time series properties of monthly corporate defaults in the US in the period 1982-2011 using financial and economic variables as exogeneous covariates. Results show......We develop a class of Poisson autoregressive models with additional covariates (PARX) that can be used to model and forecast time series of counts. We establish the time series properties of the models, including conditions for stationarity and existence of moments. These results are in turn used...... that our model is able to capture the time series dynamics of corporate defaults well, including the well-known default counts clustering found in data. Moreover, we find that while in general current defaults do indeed affect the probability of other firms defaulting in the future, in recent years...

  5. Multigroup covariance matrices for fast-reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.D. III; Broadhead, B.L.

    1981-04-01

    This report presents the multigroup covariance matrices based on the ENDF/B-V nuclear data evaluations. The materials and reactions have been chosen according to the specifications of ORNL-5517. Several cross section covariances, other than those specified by that report, are included due to the derived nature of the uncertainty files in ENDF/B-V. The materials represented are Ni, Cr, /sup 16/O, /sup 12/C, Fe, Na, /sup 235/U, /sup 238/U, /sup 239/Pu, /sup 240/Pu, /sup 241/Pu, and /sup 10/B (present due to its correlation to /sup 238/U). The data have been originally processed into a 52-group energy structure by PUFF-II and subsequently collapsed to smaller subgroup strutures. The results are illustrated in 52-group correlation matrix plots and tabulated into thirteen groups for convenience.

  6. Covariance in models of loop quantum gravity: Spherical symmetry

    CERN Document Server

    Bojowald, Martin; Reyes, Juan D

    2015-01-01

    Spherically symmetric models of loop quantum gravity have been studied recently by different methods that aim to deal with structure functions in the usual constraint algebra of gravitational systems. As noticed by Gambini and Pullin, a linear redefinition of the constraints (with phase-space dependent coefficients) can be used to eliminate structure functions, even Abelianizing the more-difficult part of the constraint algebra. The Abelianized constraints can then easily be quantized or modified by putative quantum effects. As pointed out here, however, the method does not automatically provide a covariant quantization, defined as an anomaly-free quantum theory with a classical limit in which the usual (off-shell) gauge structure of hypersurface deformations in space-time appears. The holonomy-modified vacuum theory based on Abelianization is covariant in this sense, but matter theories with local degrees of freedom are not. Detailed demonstrations of these statements show complete agreement with results of ...

  7. Noise Covariance Properties in Dual-Tree Wavelet Decompositions

    CERN Document Server

    Chaux, Caroline; Duval, Laurent; 10.1109/TIT.2007.909104

    2011-01-01

    Dual-tree wavelet decompositions have recently gained much popularity, mainly due to their ability to provide an accurate directional analysis of images combined with a reduced redundancy. When the decomposition of a random process is performed -- which occurs in particular when an additive noise is corrupting the signal to be analyzed -- it is useful to characterize the statistical properties of the dual-tree wavelet coefficients of this process. As dual-tree decompositions constitute overcomplete frame expansions, correlation structures are introduced among the coefficients, even when a white noise is analyzed. In this paper, we show that it is possible to provide an accurate description of the covariance properties of the dual-tree coefficients of a wide-sense stationary process. The expressions of the (cross-)covariance sequences of the coefficients are derived in the one and two-dimensional cases. Asymptotic results are also provided, allowing to predict the behaviour of the second-order moments for larg...

  8. Transformation rule for covariance matrices under Bell-like detections

    CERN Document Server

    Spedalieri, Gaetana; Pirandola, Stefano

    2013-01-01

    Starting from the transformation rule of a covariance matrix under homodyne detections, we can easily derive a formula for the transformation of a covariance matrix of (n+2) bosonic modes under Bell-like detections, where the last two modes are combined in an arbitrary beam splitter (i.e., with arbitrary transmissivity) and then homodyned. This formula can be specialized to describe the standard Bell detection and the heterodyne measurement, which are exploited in many contexts, including protocols of quantum teleportation, entanglement swapping and quantum cryptography. Our general formula can be adopted to study these protocols in the presence of experimental imperfections or asymmetric setups, e.g., deriving from the use of unbalanced beam splitters.

  9. Deformed Covariant Quantum Phase Spaces as Hopf Algebroids

    CERN Document Server

    Lukierski, Jerzy

    2015-01-01

    We consider the general D=4 (10+10)-dimensional kappa-deformed quantum phase space as given by Heisenberg double \\mathcal{H} of D=4 kappa-deformed Poincare-Hopf algebra H. The standard (4+4) -dimensional kappa - deformed covariant quantum phase space spanned by kappa - deformed Minkowski coordinates and commuting momenta generators ({x}_{\\mu },{p}_{\\mu }) is obtained as the subalgebra of \\mathcal{H}. We study further the property that Heisenberg double defines particular quantum spaces with Hopf algebroid structure. We calculate by using purely algebraic methods the explicite Hopf algebroid structure of standard kappa - deformed quantum covariant phase space in Majid-Ruegg bicrossproduct basis. The coproducts for Hopf algebroids are not unique, determined modulo the coproduct gauge freedom. Finally we consider the interpretation of the algebraic description of quantum phase spaces as Hopf bialgebroids.

  10. Batalin-Vilkovisky formalism in locally covariant field theory

    CERN Document Server

    Rejzner, Katarzyna

    2011-01-01

    The present work contains a complete formulation of the Batalin-Vilkovisky (BV) formalism in the framework of locally covariant field theory. In the first part of the thesis the classical theory is investigated with a particular focus on the infinite dimensional character of the underlying structures. It is shown that the use of infinite dimensional differential geometry allows for a conceptually clear and elegant formulation. The construction of the BV complex is performed in a fully covariant way and we also generalize the BV framework to a more abstract level, using functors and natural transformations. In this setting we construct the BV complex for classical gravity. This allows us to give a homological interpretation to the notion of diffeomorphism invariant physical quantities in general relativity. The second part of the thesis concerns the quantum theory. We provide a framework for the BV quantization that doesn't rely on the path integral formalism, but is completely formulated within perturbative a...

  11. The Unexpected Awakening of Chaitén Volcano, Chile

    Science.gov (United States)

    Carn, Simon A.; Pallister, John S.; Lara, Luis; Ewert, John W.; Watt, Sebastian; Prata, Alfred J.; Thomas, Ronald J.; Villarosa, Gustavo

    2009-06-01

    On 2 May 2008, a large eruption began unexpectedly at the inconspicuous Chaitén volcano in Chile's southern volcanic zone. Ash columns abruptly jetted from the volcano into the stratosphere, followed by lava dome effusion and continuous low-altitude ash plumes [Lara, 2009]. Apocalyptic photographs of eruption plumes suffused with lightning were circulated globally. Effects of the eruption were extensive. Floods and lahars inundated the town of Chaitén, and its 4625 residents were evacuated. Widespread ashfall and drifting ash clouds closed regional airports and cancelled hundreds of domestic flights in Argentina and Chile and numerous international flights [Guffanti et al., 2008]. Ash heavily affected the aquaculture industry in the nearby Gulf of Corcovado, curtailed ecotourism, and closed regional nature preserves. To better prepare for future eruptions, the Chilean government has boosted support for monitoring and hazard mitigation at Chaitén and at 42 other highly hazardous, active volcanoes in Chile.

  12. Desigualdad Geográfica en Chile

    Directory of Open Access Journals (Sweden)

    Claudio A. Agostini

    2007-03-01

    Full Text Available Despite success in reducing poverty over the last twenty years, inequality in Chile has remained virtually unchanged, making Chile one of the least equal countries in the world. High levels of inequality have been shown to hamper further reductions in poverty as well as economic growth and local inequality has been shown to affect such outcomes as violence and health. The study of inequality at the local level is thus crucial for understanding the economic well-being of a country. Local measures of inequality have been difficult to obtain, but recent theoretical advances have enabled the combination of survey and census data to obtain estimators of inequality that are robust at disaggregated geographic levels. In this paper, we employ this methodology to produce consistent estimators of inequality for every county in Chile. We find a great deal of variation in inequality, with countylevel Gini coefficients ranging from 0.41 to 0.63.

  13. Globalization, Inequality, and Transnational Activism: A Case Study on Chile

    Directory of Open Access Journals (Sweden)

    Moctezuma Garcia

    2013-09-01

    Full Text Available Globalization has transformed how states are governed through a neoliberal economic approach that reinforces an unregulated capitalist market. An emphasis on Chile is important because it was the first state in Latin America to apply neoliberalism and has been hailed as a prime example for other developing states to integrate similar strategies to strengthen the local economy. However, inequality continues to persist despite economic gains. A combination of historical struggles affecting victims of the Pinochet era and present struggles with poverty, have resulted in a constant conflict between the power elite and the rest of society. Social movements in Chile have played a pivotal role in raising international awareness and pressuring the local government to protect the rights of highly vulnerable populations. A focus on transnational activism provides an effective medium for local and international advocates to work together toward holding Chile accountable for addressing social disparities.

  14. The Unexpected Awakening of Chaitén Volcano, Chile

    Science.gov (United States)

    Carn, Simon A.; Zogorski, John S.; Lara, Luis; Ewert, John W.; Watt, Sebastian; Prata, Alfred J.; Thomas, Ronald J.; Villarosa, Gustavo

    2009-01-01

    On 2 May 2008, a large eruption began unexpectedly at the inconspicuous Chaitén volcano in Chile's southern volcanic zone. Ash columns abruptly jetted from the volcano into the stratosphere, followed by lava dome effusion and continuous low-altitude ash plumes [Lara, 2009]. Apocalyptic photographs of eruption plumes suffused with lightning were circulated globally. Effects of the eruption were extensive. Floods and lahars inundated the town of Chaitén, and its 4625 residents were evacuated. Widespread ashfall and drifting ash clouds closed regional airports and cancelled hundreds of domestic flights in Argentina and Chile and numerous international flights [Guffanti et al., 2008]. Ash heavily affected the aquaculture industry in the nearby Gulf of Corcovado, curtailed ecotourism, and closed regional nature preserves. To better prepare for future eruptions, the Chilean government has boosted support for monitoring and hazard mitigation at Chaitén and at 42 other highly hazardous, active volcanoes in Chile.

  15. Covariant GNS Representation for C*-Dynamical Systems

    CERN Document Server

    Pandiscia, Carlo

    2012-01-01

    We extend the covariant GNS representation of Niculescu, Str\\"oh and Zsid\\'o for C*-dynamical systems with time-evolution of the system (dynamics) a homomorphism of C*-algebras, to any dynamical systems, where the dynamics is an unital completely positive map. We give also an overview on its application to the reversible dilation theory as formulated by B. Kummerer.

  16. Flavour covariant transport equations: An application to resonant leptogenesis

    Directory of Open Access Journals (Sweden)

    P.S. Bhupal Dev

    2014-09-01

    Full Text Available We present a fully flavour-covariant formalism for transport phenomena, by deriving Markovian master equations that describe the time-evolution of particle number densities in a statistical ensemble with arbitrary flavour content. As an application of this general formalism, we study flavour effects in a scenario of resonant leptogenesis (RL and obtain the flavour-covariant evolution equations for heavy-neutrino and lepton number densities. This provides a complete and unified description of RL, capturing three distinct physical phenomena: (i the resonant mixing between the heavy-neutrino states, (ii coherent oscillations between different heavy-neutrino flavours, and (iii quantum decoherence effects in the charged-lepton sector. To illustrate the importance of this formalism, we numerically solve the flavour-covariant rate equations for a minimal RL model and show that the total lepton asymmetry can be enhanced by up to one order of magnitude, as compared to that obtained from flavour-diagonal or partially flavour off-diagonal rate equations. Thus, the viable RL model parameter space is enlarged, thereby enhancing further the prospects of probing a common origin of neutrino masses and the baryon asymmetry in the Universe at the LHC, as well as in low-energy experiments searching for lepton flavour and number violation. The key new ingredients in our flavour-covariant formalism are rank-4 rate tensors, which are required for the consistency of our flavour-mixing treatment, as shown by an explicit calculation of the relevant transition amplitudes by generalizing the optical theorem. We also provide a geometric and physical interpretation of the heavy-neutrino degeneracy limits in the minimal RL scenario. Finally, we comment on the consistency of various suggested forms for the heavy-neutrino self-energy regulator in the lepton-number conserving limit.

  17. Covariant Quantization of the Brink-Schwarz Superparticle

    CERN Document Server

    Grassi, P A; Porrati, Massimo

    2001-01-01

    The quantization of the Brink-Schwarz-Casalbuoni superparticle is performed in an explicitly covariant way using the antibracket formalism. Since an infinite number of ghost fields are required, within a suitable off-shell twistor-like formalism, we are able to fix the gauge of each ghost sector without modifying the physical content of the theory. The computation reveals that the antibracket cohomology contains only the physical degrees of freedom.

  18. Collective Flow of A Hyperons within Covariant Kaon Dynamics

    Institute of Scientific and Technical Information of China (English)

    XING Yong-Zhong; ZHU Yu-Lan; WANG Yan-Yan; ZHENG Yu-Ming

    2011-01-01

    @@ The collective flow of ∧ hyperons produced in association with positively charged kaon mesons in nuclear reactions at SIS energies is studied using the quantum molecular dynamics(QMD)model within covariant kaon dynamics Our calculation indicates that both the directed and differential directed flows of ∧s are almost in agreement with the experimental data.This suggest that the covariant kaon dynamics based on the chiral mean field approximation can not only explain the collective flow of kaon mesons,but also give reasonable results for the collective flow of ∧ hyperons at SIS energies.The final-state interaction of ∧ hyperons with dense nuclear matter enhances their directed flow and improves the agreement of their differential directed flow with the experimental data.The influence of the interaction on the ∧ collective flow is more appreciable at large rapidity or transverse momentum region.%The collective How of A hyperons produced in association with positively charged kaon mesons in nuclear reactions at SIS energies is studied using the quantum molecular dynamics (QMD) model within covariant kaon dynamics. Our calculation indicates that both the directed and differential directed Sows of As are almost in agreement with the experimental data. This suggest that the covariant kaon dynamics based on the chiral mean Geld approximation can not only explain the collective flow of kaon mesons, but also give reasonable results for the collective How of A hyperons at SIS energies. The Hnal-state interaction of A hyperons with dense nuclear matter enhances their directed How and improves the agreement of their differential directed How with the experimental data. The influence of the interaction on the A collective How is more appreciable at iarge rapidity or transverse momentum region.

  19. Covariance in models of loop quantum gravity: Gowdy systems

    CERN Document Server

    Bojowald, Martin

    2015-01-01

    Recent results in the construction of anomaly-free models of loop quantum gravity have shown obstacles when local physical degrees of freedom are present. Here, a set of no-go properties is derived in polarized Gowdy models, raising the question whether these systems can be covariant beyond a background treatment. As a side product, it is shown that normal deformations in classical polarized Gowdy models can be Abelianized.

  20. Dunkl Operators as Covariant Derivatives in a Quantum Principal Bundle

    OpenAIRE

    Micho Đurđevich; Stephen Bruce Sontz

    2011-01-01

    A quantum principal bundle is constructed for every Coxeter group acting on a finite-dimensional Euclidean space $E$, and then a connection is also defined on this bundle. The covariant derivatives associated to this connection are the Dunkl operators, originally introduced as part of a program to generalize harmonic analysis in Euclidean spaces. This gives us a new, geometric way of viewing the Dunkl operators. In particular, we present a new proof of the commutativity of these operators amo...

  1. Higher covariant derivative regulators and non-multiplicative renormalization

    Energy Technology Data Exchange (ETDEWEB)

    Martin, C.P. [Universidad Autonoma de Madrid (Spain). Dept. de Fisica Teorica; Ruiz Ruiz, F. [Nationaal Inst. voor Kernfysica en Hoge-Energiefysica (NIKHEF), Amsterdam (Netherlands). Sectie H

    1994-12-31

    The renormalization algorithm based on regularization methods with two regulators is analyzed by means of explicit computations. We show in particular that regularization by higher covariant derivative terms can be complemented with dimensional regularization to obtain a consistent renormalized 4-dimensional Yang-Mills theory at the one-loop level. This shows that hybrid regularization methods can be applied not only to finite theories, like e.g. Chern-Simons, but also to divergent theories. (orig.).

  2. The Photon Wavefunction: a covariant formulation and equivalence with QED

    OpenAIRE

    Tamburini, Fabrizio; Vicino, Denise

    2008-01-01

    We discuss the limits of the photon wavefunction (PWF) formalism, which is experiencing a revival in these days from the new practical applications in photonics and quantum optics. We build a Dirac-like equation for the PWF written in a manifestly covariant form and show that, in presence of charged matter fields, it reproduces the standard formulation of (classical) Electrodinamics. This shows the inconsistency of the attempts to construct a quantum theory of interacting photons, based on th...

  3. Testing the Equality of Covariance Operators in Functional Samples

    CERN Document Server

    Fremdt, Stefan; Kokoszka, Piotr; Steinebach, Josef G

    2011-01-01

    We propose a robust test for the equality of the covariance structures in two functional samples. The test statistic has a chi-square asymptotic distribution with a known number of degrees of freedom, which depends on the level of dimension reduction needed to represent the data. Detailed analysis of the asymptotic properties is developed. Finite sample performance is examined by a simulation study and an application to egg-laying curves of fruit flies.

  4. Hydrodynamic Covariant Symplectic Structure from Bilinear Hamiltonian Functions

    Directory of Open Access Journals (Sweden)

    Capozziello S.

    2005-07-01

    Full Text Available Starting from generic bilinear Hamiltonians, constructed by covariant vector, bivector or tensor fields, it is possible to derive a general symplectic structure which leads to holonomic and anholonomic formulations of Hamilton equations of motion directly related to a hydrodynamic picture. This feature is gauge free and it seems a deep link common to all interactions, electromagnetism and gravity included. This scheme could lead toward a full canonical quantization.

  5. Do Time-Varying Covariances, Volatility Comovement and Spillover Matter?

    OpenAIRE

    Lakshmi Balasubramanyan

    2005-01-01

    Financial markets and their respective assets are so intertwined; analyzing any single market in isolation ignores important information. We investigate whether time varying volatility comovement and spillover impact the true variance-covariance matrix under a time-varying correlation set up. Statistically significant volatility spillover and comovement between US, UK and Japan is found. To demonstrate the importance of modelling volatility comovement and spillover, we look at a simple portfo...

  6. Spin Structure Functions in a Covariant Spectator Quark Model

    Energy Technology Data Exchange (ETDEWEB)

    G. Ramalho, Franz Gross and M. T. Peña

    2010-12-01

    We apply the covariant spectator quark–diquark model, already probed in the description of the nucleon elastic form factors, to the calculation of the deep inelastic scattering (DIS) spin-independent and spin-dependent structure functions of the nucleon. The nucleon wave function is given by a combination of quark–diquark orbital states, corresponding to S, D and P-waves. A simple form for the quark distribution function associated to the P and D waves is tested.

  7. Threshold regression for survival data with time-varying covariates.

    Science.gov (United States)

    Lee, Mei-Ling Ting; Whitmore, G A; Rosner, Bernard A

    2010-03-30

    Time-to-event data with time-varying covariates pose an interesting challenge for statistical modeling and inference, especially where the data require a regression structure but are not consistent with the proportional hazard assumption. Threshold regression (TR) is a relatively new methodology based on the concept that degradation or deterioration of a subject's health follows a stochastic process and failure occurs when the process first reaches a failure state or threshold (a first-hitting-time). Survival data with time-varying covariates consist of sequential observations on the level of degradation and/or on covariates of the subject, prior to the occurrence of the failure event. Encounters with this type of data structure abound in practical settings for survival analysis and there is a pressing need for simple regression methods to handle the longitudinal aspect of the data. Using a Markov property to decompose a longitudinal record into a series of single records is one strategy for dealing with this type of data. This study looks at the theoretical conditions for which this Markov approach is valid. The approach is called threshold regression with Markov decomposition or Markov TR for short. A number of important special cases, such as data with unevenly spaced time points and competing risks as stopping modes, are discussed. We show that a proportional hazards regression model with time-varying covariates is consistent with the Markov TR model. The Markov TR procedure is illustrated by a case application to a study of lung cancer risk. The procedure is also shown to be consistent with the use of an alternative time scale. Finally, we present the connection of the procedure to the concept of a collapsible survival model.

  8. Biogeografía marina de Chile continental Marine biogeography of continental Chile

    Directory of Open Access Journals (Sweden)

    PATRICIO A. CAMUS

    2001-09-01

    Full Text Available Por casi un siglo, varios autores han analizado los patrones de distribución de la fauna y flora marina del Pacífico de Sudamérica y de la costa de Chile en particular, con el propósito de establecer el número de las unidades biogeográficas presentes. Si bien los patrones generales actuales son relativamente bien conocidos, la mayoría de los estudios se ha enfocado en las discontinuidades distribucionales y en propuestas de clasificación más que en los factores y procesos dinámicos que han formado las unidades espaciales identificadas. Aun en el caso de las clasificaciones, las conclusiones publicadas se basan principalmente en el análisis de uno o pocos grupos seleccionados, y presentan diferencias importantes en los criterios de selección de los grupos, el número de especies involucrado y la metodología usada. Por otra parte, las discrepancias entre estudios específicos tienden a obscurecer un fenómeno relevante y de mayor escala como es la dinámica de las biotas, uno de los aspectos biogeográficos menos conocidos en Chile. En tal contexto, este trabajo presenta una revisión de literatura sobre la biogeografía marina de Chile y sus aspectos asociados, con los siguientes objetivos: (a resumir las características oceanográficas, climáticas y geomorfológicas de la costa continental de Chile; (b discutir 27 clasificaciones biogeográficas publicadas para la costa chilena, analizando los criterios y procedimientos usados por los autores, sus conclusiones principales, y la concordancia entre los estudios; (c evaluar los procesos dispersivos y vicariantes asociados a los desplazamientos y modificaciones de las biotas de la región, en función de los antecedentes disponibles sobre las condiciones existentes y los principales eventos ocurridos durante los períodos Terciario y Cuaternario; y (d proponer un escenario de cambio biogeográfico basado en determinantes históricas y su influencia en la formación, carácter y din

  9. Covariant density functional theory: Reexamining the structure of superheavy nuclei

    CERN Document Server

    Agbemava, S E; Nakatsukasa, T; Ring, P

    2015-01-01

    A systematic investigation of even-even superheavy elements in the region of proton numbers $100 \\leq Z \\leq 130$ and in the region of neutron numbers from the proton-drip line up to neutron number $N=196$ is presented. For this study we use five most up-to-date covariant energy density functionals of different types, with a non-linear meson coupling, with density dependent meson couplings, and with density-dependent zero-range interactions. Pairing correlations are treated within relativistic Hartree-Bogoliubov (RHB) theory based on an effective separable particle-particle interaction of finite range and deformation effects are taken into account. This allows us to assess the spread of theoretical predictions within the present covariant models for the binding energies, deformation parameters, shell structures and $\\alpha$-decay half-lives. Contrary to the previous studies in covariant density functional theory, it was found that the impact of $N=172$ spherical shell gap on the structure of superheavy elemen...

  10. Allometric covariation: a hallmark behavior of plants and leaves.

    Science.gov (United States)

    Price, Charles A; Weitz, Joshua S

    2012-03-01

    Size is one of the most important axes of variation among plants. As such, plant biologists have long searched for unifying principles that can explain how matter and energy flux and organ partitioning scale with plant size. Several recent models have proposed a universal biophysical basis for numerous scaling phenomena in plants based on vascular network geometry. Here, we review statistical analyses of several large-scale plant datasets that demonstrate that a true hallmark of plant form variability is systematic covariation among traits. This covariation is constrained by allometries that combine and trade off with one another, rather than any single universal allometric scaling exponent for a trait or suite of traits. Further, we show that covariation can be successfully modeled using network approaches that allow for species-specific designs in plants and geometric approaches that constrain relationships among economic traits in leaves. Finally, we report large-scale efforts utilizing semi-automated software tools that quantify physical networks and can inform our attempts to link vascular network structure to plant form and function. Collectively, this work highlights how the linking of morphology, biomass partitioning and the structure of physical distribution networks can improve our empirical and theoretical understanding of important drivers of plant functional diversity.

  11. MIMO Radar Transmit Beampattern Design Without Synthesising the Covariance Matrix

    KAUST Repository

    Ahmed, Sajid

    2013-10-28

    Compared to phased-array, multiple-input multiple-output (MIMO) radars provide more degrees-offreedom (DOF) that can be exploited for improved spatial resolution, better parametric identifiability, lower side-lobe levels at the transmitter/receiver, and design variety of transmit beampatterns. The design of the transmit beampattern generally requires the waveforms to have arbitrary auto- and crosscorrelation properties. The generation of such waveforms is a two step complicated process. In the first step a waveform covariance matrix is synthesised, which is a constrained optimisation problem. In the second step, to realise this covariance matrix actual waveforms are designed, which is also a constrained optimisation problem. Our proposed scheme converts this two step constrained optimisation problem into a one step unconstrained optimisation problem. In the proposed scheme, in contrast to synthesising the covariance matrix for the desired beampattern, nT independent finite-alphabet constantenvelope waveforms are generated and pre-processed, with weight matrix W, before transmitting from the antennas. In this work, two weight matrices are proposed that can be easily optimised for the desired symmetric and non-symmetric beampatterns and guarantee equal average power transmission from each antenna. Simulation results validate our claims.

  12. Resting-state brain organization revealed by functional covariance networks.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Zhang

    Full Text Available BACKGROUND: Brain network studies using techniques of intrinsic connectivity network based on fMRI time series (TS-ICN and structural covariance network (SCN have mapped out functional and structural organization of human brain at respective time scales. However, there lacks a meso-time-scale network to bridge the ICN and SCN and get insights of brain functional organization. METHODOLOGY AND PRINCIPAL FINDINGS: We proposed a functional covariance network (FCN method by measuring the covariance of amplitude of low-frequency fluctuations (ALFF in BOLD signals across subjects, and compared the patterns of ALFF-FCNs with the TS-ICNs and SCNs by mapping the brain networks of default network, task-positive network and sensory networks. We demonstrated large overlap among FCNs, ICNs and SCNs and modular nature in FCNs and ICNs by using conjunctional analysis. Most interestingly, FCN analysis showed a network dichotomy consisting of anti-correlated high-level cognitive system and low-level perceptive system, which is a novel finding different from the ICN dichotomy consisting of the default-mode network and the task-positive network. CONCLUSION: The current study proposed an ALFF-FCN approach to measure the interregional correlation of brain activity responding to short periods of state, and revealed novel organization patterns of resting-state brain activity from an intermediate time scale.

  13. Bilinear covariants and spinor fields duality in quantum Clifford algebras

    Energy Technology Data Exchange (ETDEWEB)

    Abłamowicz, Rafał, E-mail: rablamowicz@tntech.edu [Department of Mathematics, Box 5054, Tennessee Technological University, Cookeville, Tennessee 38505 (United States); Gonçalves, Icaro, E-mail: icaro.goncalves@ufabc.edu.br [Instituto de Matemática e Estatística, Universidade de São Paulo, Rua do Matão, 1010, 05508-090, São Paulo, SP (Brazil); Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, 09210-170 Santo André, SP (Brazil); Rocha, Roldão da, E-mail: roldao.rocha@ufabc.edu.br [Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, 09210-170 Santo André, SP (Brazil); International School for Advanced Studies (SISSA), Via Bonomea 265, 34136 Trieste (Italy)

    2014-10-15

    Classification of quantum spinor fields according to quantum bilinear covariants is introduced in a context of quantum Clifford algebras on Minkowski spacetime. Once the bilinear covariants are expressed in terms of algebraic spinor fields, the duality between spinor and quantum spinor fields can be discussed. Thus, by endowing the underlying spacetime with an arbitrary bilinear form with an antisymmetric part in addition to a symmetric spacetime metric, quantum algebraic spinor fields and deformed bilinear covariants can be constructed. They are thus compared to the classical (non quantum) ones. Classes of quantum spinor fields classes are introduced and compared with Lounesto's spinor field classification. A physical interpretation of the deformed parts and the underlying Z-grading is proposed. The existence of an arbitrary bilinear form endowing the spacetime already has been explored in the literature in the context of quantum gravity [S. W. Hawking, “The unpredictability of quantum gravity,” Commun. Math. Phys. 87, 395 (1982)]. Here, it is shown further to play a prominent role in the structure of Dirac, Weyl, and Majorana spinor fields, besides the most general flagpoles and flag-dipoles. We introduce a new duality between the standard and the quantum spinor fields, by showing that when Clifford algebras over vector spaces endowed with an arbitrary bilinear form are taken into account, a mixture among the classes does occur. Consequently, novel features regarding the spinor fields can be derived.

  14. Fractal Video Coding Using Fast Normalized Covariance Based Similarity Measure

    Directory of Open Access Journals (Sweden)

    Ravindra E. Chaudhari

    2016-01-01

    Full Text Available Fast normalized covariance based similarity measure for fractal video compression with quadtree partitioning is proposed in this paper. To increase the speed of fractal encoding, a simplified expression of covariance between range and overlapped domain blocks within a search window is implemented in frequency domain. All the covariance coefficients are normalized by using standard deviation of overlapped domain blocks and these are efficiently calculated in one computation by using two different approaches, namely, FFT based and sum table based. Results of these two approaches are compared and they are almost equal to each other in all aspects, except the memory requirement. Based on proposed simplified similarity measure, gray level transformation parameters are computationally modified and isometry transformations are performed using rotation/reflection properties of IFFT. Quadtree decompositions are used for the partitions of larger size of range block, that is, 16 × 16, which is based on target level of motion compensated prediction error. Experimental result shows that proposed method can increase the encoding speed and compression ratio by 66.49% and 9.58%, respectively, as compared to NHEXS method with increase in PSNR by 0.41 dB. Compared to H.264, proposed method can save 20% of compression time with marginal variation in PSNR and compression ratio.

  15. Full covariance of CMB and lensing reconstruction power spectra

    Science.gov (United States)

    Peloton, Julien; Schmittfull, Marcel; Lewis, Antony; Carron, Julien; Zahn, Oliver

    2017-02-01

    CMB and lensing reconstruction power spectra are powerful probes of cosmology. However, they are correlated, since the CMB power spectra are lensed, and the lensing reconstruction is constructed using CMB multipoles. We perform a full analysis of the auto- and cross-covariances, including polarization power spectra and minimum-variance lensing estimators, and compare with simulations of idealized future CMB-S4 observations. Covariances sourced by fluctuations in the unlensed CMB and instrumental noise can largely be removed by using a realization-dependent subtraction of lensing reconstruction noise, leaving a relatively simple covariance model that is dominated by lensing-induced terms and well described by a small number of principal components. The correlations between the CMB and lensing power spectra will be detectable at the level of ˜5 σ for a CMB-S4 mission, and neglecting them could underestimate some parameter error bars by several tens of percent. However, we found that the inclusion of external priors or data sets to estimate parameter error bars can make the impact of the correlations almost negligible.

  16. A Covariant model for the nucleon and the $\\Delta$

    CERN Document Server

    Ramalho, G; Gross, Franz

    2008-01-01

    The covariant spectator formalism is used to model the nucleon and the $\\Delta$(1232) as a system of three constituent quarks with their own electromagnetic structure. The definition of the ``fixed-axis'' polarization states for the diquark emitted from the initial state vertex and absorbed into the final state vertex is discussed. The helicity sum over those states is evaluated and seen to be covariant. Using this approach, all four electromagnetic form factors of the nucleon, together with the {\\it magnetic} form factor, $G_M^*$, for the $\\gamma N \\to \\Delta$ transition, can be described using manifestly covariant nucleon and $\\Delta$ wave functions with {\\it zero} orbital angular momentum $L$, but a successful description of $G_M^*$ near $Q^2=0$ requires the addition of a pion cloud term not included in the class of valence quark models considered here. We also show that the pure $S$-wave model gives electric, $G_E^*$, and coulomb, $G^*_C$, transition form factors that are identically zero, showing that th...

  17. Spatial implications of covariate adjustment on patterns of risk

    DEFF Research Database (Denmark)

    Sabel, Clive Eric; Wilson, Jeff Gaines; Kingham, Simon

    2007-01-01

    Epidemiological studies that examine the relationship between environmental exposures and health often address other determinants of health that may influence the relationship being studied by adjusting for these factors as covariates. While disease surveillance methods routinely control for cova......Epidemiological studies that examine the relationship between environmental exposures and health often address other determinants of health that may influence the relationship being studied by adjusting for these factors as covariates. While disease surveillance methods routinely control......), then for a deprivation index, and finally for both PM10 and deprivation. Spatial patterns of risk, disease clusters and cold and hot spots were generated using a spatial scan statistic and a Getis-Ord Gi* statistic. In all disease groups tested (except the control disease), adjustment for chronic PM10 exposure...... area to a mixed residential/industrial area, possibly introducing new environmental exposures. Researchers should be aware of the potential spatial effects inherent in adjusting for covariates when considering study design and interpreting results. © 2007 Elsevier Ltd. All rights reserved....

  18. The epidermis in Passerina/ (Thymelaeaceae: structure, function and taxonomic significance

    Directory of Open Access Journals (Sweden)

    C. L. Bredenkamp

    2000-12-01

    Full Text Available Epidermal features were studied in all 17 species of Passerina, a genus endemic to southern Africa. Leaves in Passerina are inversely ericoid, the adaxial surface concave and the abaxial surface convex. Leaves are inversely dorsiventral and epistomatic. The adaxial epidermis is villous, with unicellular, uniseriate trichomes and relatively small thin-walled cells, promoting flexibility of leaf margins owing to turgor changes. In common with many other Thymelaeaceae, abaxial epidermal cells are large and tanniniferous with mucilaginous cell walls. The cuticle is adaxially thin, but abaxially well devel­oped, probably enabling the leaf to restrict water loss and to tolerate high light intensity and UV-B radiation. Epicuticular waxes, present in all species, comprise both soft and plate waxes. Epidermal structure proves to be taxonomically impor­tant at family, genus and species levels. Interspecific differences include arrangement of stomata and presence or absence of abaxial epidermal hair. Other diagnostic characters of the abaxial epidermal cells are arrangement,size and shape, cutic- ular ornamentation and presence or absence of wax platelets. Two groups of species on the basis of abaxial epidermal cell orientation are recognised. Many leaf epidermal features in Passerina are interpreted as structural adaptations to the Mediterranean climate of the Cape.

  19. PAMPATHERIIDAE (XENARTHRA, CINGULATA FROM TARIJA VALLEY, BOLIVIA: A TAXONOMIC UPDATE

    Directory of Open Access Journals (Sweden)

    SANTIAGO RODRIGUEZ-BUALÓ

    2014-07-01

    Full Text Available Pampatheriidae (Middle Miocene-late Pleistocene constitutes an extinct clade of Cingulata widely dispersed in South America, entering in Central and North America during the Great American Biotic Interchange. In the Pleistocene of South America, two genera are recorded: Pampatherium (with three species and Holmesina (with six species. In the Pleistocene palaeofauna of Tarija Valley (Bolivia one of the most conspicuous recorded taxa are the Cingulata, including Pampatheriidae. Until this contribution, all the remains were classified as P. typum and Pampatherium sp. Here we present a modern taxonomic revision of the Pampatheriidae of the Tarija Valley, based on previous collected and published material together with new materials obtained from fieldwork carried out during 2011-2013. The evidence indicates that a single species of Pampatheriidae is present in the Tarija Valley ( Pampatherium humboldtii , whereas the presence of P.  typum in discarded. From a chrono-stratigraphic point of view, the biochron of this species is restricted to the late Pleistocene. This supports previous hypothesis on the age of the sediments of Tarija Valley (Tolomosa Formation.

  20. Karyotypes of parasitic Hymenoptera: Diversity, evolution and taxonomic significance

    Institute of Scientific and Technical Information of China (English)

    VLADIMIR E. GOKHMAN

    2006-01-01

    Haploid chromosome numbers (n) of parasitic Hymenoptera (= traditional Parasitica + Chrysidoidea) vary from 2 to 23. However, this range can be subdivided into three intervals with n = 14-23 (less derived parasitic wasps, e.g., some Ichneumonidae and Braconidae as well as Gasteruptiidae), 8-13 (many other parasitic Hymenoptera) and 2-7(Dryinidae, the majority of Chalcidoidea and some advanced Braconidae, e.g. Aphidiinae).The symmetric karyotype with a relatively high chromosome number (n = 14-17) and the prevalence of biarmed chromosomes must be considered as a groundplan feature of parasitic Hymenoptera. Independent reductions of chromosome numbers (n ≤ 10-11) occurred in some groups of the superfamily Ichneumonoidea as well as in the common ancestor of the Proctotrupoidea sensu lato, Ceraphronoidea, Cynipoidea and Chalcidoidea. Further multiple decreases in chromosome numbers (n ≤ 4-6) took place in some Braconidae, various lineages of the superfamily Chalcidoidea as well as in the family Dryinidae. Two main trends prevailed in the karyotype evolution of parasitic wasps: the reduction of chromosome numbers (mainly due to tandem fusions and less frequently due to centric ones) and karyotypic dissymmetrization (through an increase in size differentiation of chromosomes and/or in the share of acrocentrics in a chromosome set). Although karyotypic features of parasitic Hymenoptera can be used for solving taxonomic problems at various levels, this method is the most effective at the species level.

  1. Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

    Energy Technology Data Exchange (ETDEWEB)

    Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-06-01

    The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

  2. Taxonomic status of the Columbia duskysnail (Truncatelloidea, Amnicolidae, Colligyrus

    Directory of Open Access Journals (Sweden)

    Hsiu-Ping Liu

    2015-07-01

    Full Text Available Undescribed freshwater snails (Amnicolidae: Colligyrus from the Mount Hood region (northwestern United States identified as a new species (commonly known as the Columbia duskysnail in grey literature have been provided federal protection under the “survey and manage” provisions of the Northwest Forest Plan and have been placed on conservation watch lists. However, there are no published studies of the identity of these snails aside from a molecular phylogenetic analysis which delineated a close relationship between the single sampled population and C. greggi, which is distributed more than 750 km to the east of the Mount Hood area. Here we examine the taxonomic status of the Columbia duskysnail based on additional molecular sampling of mitochondrial DNA sequences (COI and morphological evidence. We found that the Columbia duskysnail is not a monophyletic group and forms a strongly supported clade with C. greggi. The COI divergence between these broadly disjunct groups (2.1% was somewhat larger than that within C. greggi (1.0% but considerably less than that among the three currently recognized species of Colligyrus (8.7–12.1%. Additionally we found that the Columbia duskysnail and C. greggi cannot be consistently differentiated by previously reported diagnostic characters (size and shape of shell spire, pigmentation of body and penis and are closely similar in other aspects of morphology. Based on these results we conclude that the Columbia duskysnail is conspecific with C. greggi.

  3. Taxonomic review of the Sebastes pachycephalus complex (Scorpaeniformes: Scorpaenidae).

    Science.gov (United States)

    Kai, Yoshiaki; Nakabo, Tetsuji

    2013-01-01

    A taxonomic review of the Sebastes pachycephalus complex established the existence of two valid species, S. pachycephalus and S. nudus. Similarities between them include: cranium armed dorsally with robust preocular, supraocular, postocular, and parietal spines; interorbital space concave; lower jaw lacking scales, shorter than upper jaw; thickened rays in ventral half of pectoral fin; dorsal fin usually with 13 spines and 12 soft-rays; pored lateral line scales 27-35 (usually 29-33). However, S. pachycephalus is distinguishable from the latter in having minute scales below the entire dorsal-fin spine base (vs. lacking minute scales below first to fifth or variously to the posteriormost spine in the latter), dark spots scattered on the dorsal, anal and caudal fins (vs. no distinct dark spots), and lacking distinct colored markings on the dorsum (vs. yellow or reddish-brown markings present). Although both species occur off the southern Korean Peninsula and in the Bohai and Yellow Seas, in Japanese waters, the former is distributed from northern Honshu Is. southward to southern Kyushu Is., whereas the latter extends from southern Hokkaido southward along the Pacific coast of Japan to Kanagawa, and along the Sea of Japan coast to northern Kyushu Is., including the Seto Inland Sea. Sebastes nigricaus, S. nigricans, and S. latus are confirmed as junior synonyms of S. pachycephalus, and S. chalcogrammus as junior synonym of S. nudus, based on the examination of type specimens.

  4. Biodiscovery from rare actinomycetes: an eco-taxonomical perspective.

    Science.gov (United States)

    Kurtböke, D I

    2012-03-01

    Microbial natural products, in particular, the ones produced by the members of the order Actinomycetales, will continue to represent an important route to the discovery of novel classes of bioactive compounds. As a result, the search for and discovery of lesser-known and/or novel actinomycetes is of significant interest to the industry due to a growing need for the development of new and potent therapeutic agents, mainly against drug resistant bacteria. Current advancements in genomics and metagenomics are adding strength to the target-directed search for detection and isolation of bioactive actinomycetes. New discoveries, however, will only stem from a sound understanding and interpretation of knowledge derived from conventional studies conducted since the discovery of streptomycin, on the ecology, taxonomy, physiology and metabolism of actinomycetes, and from a combination of this knowledge with currently available and continuously advancing molecular tools. Such a powerful information platform will then inevitably reveal the whereabouts, taxonomical and chemical identities of previously undetected bioactive actinomycetes including novel species of streptomycetes as potential producers of novel drug candidates.

  5. Taxonomic Significance of ISTR to Discriminate Species in Agavaceae

    Directory of Open Access Journals (Sweden)

    Martha I. Torres-Moran

    2008-01-01

    Full Text Available Family Agavaceae is endemic of American Continent. From the around 300 species recognized in this family, 217 occur in Mexico. Relevant ethnobotanic relationships among Agavaceae and the several native human cultures of the American Continent have been established since prehispanic times. Agave is one of the most important genus in that family due to its great diversity and abundance, mainly in arid and semiarid regions of Mexico. In this country, near to 15 species of Agave are used to elaborate alcoholic beverages. Agave tequilana weber var. azul is indubitable the most important of them because is the raw material to elaborate a particular worldly famous class of mescal, named tequila. Agave salmiana, A. maximiliana and A. durangensis are species less famous than A. tequilana, but they also have a high quality and level of carbohydrates and in fact, support local mescal industries. In these last species several taxonomic controversies exist concerning their specific delimitation. In this study the molecular characterization of eight species of Agavaceae using ISTR was performed in order to determine the significance of these markers for discriminating among specific taxa. The results suggest that these molecular markers are worthy to typify species of Agavaceae and detect intrapopulation variability.

  6. Fast and sensitive taxonomic classification for metagenomics with Kaiju.

    Science.gov (United States)

    Menzel, Peter; Ng, Kim Lee; Krogh, Anders

    2016-04-13

    Metagenomics emerged as an important field of research not only in microbial ecology but also for human health and disease, and metagenomic studies are performed on increasingly larger scales. While recent taxonomic classification programs achieve high speed by comparing genomic k-mers, they often lack sensitivity for overcoming evolutionary divergence, so that large fractions of the metagenomic reads remain unclassified. Here we present the novel metagenome classifier Kaiju, which finds maximum (in-)exact matches on the protein-level using the Burrows-Wheeler transform. We show in a genome exclusion benchmark that Kaiju classifies reads with higher sensitivity and similar precision compared with current k-mer-based classifiers, especially in genera that are underrepresented in reference databases. We also demonstrate that Kaiju classifies up to 10 times more reads in real metagenomes. Kaiju can process millions of reads per minute and can run on a standard PC. Source code and web server are available at http://kaiju.binf.ku.dk.

  7. Marine actinomycetes from Madeira Archipelago preliminary taxonomic studies

    Directory of Open Access Journals (Sweden)

    Ilda Santos Sanches

    2014-06-01

    Full Text Available The oceans cover 70 % of the Earth´s surface and harbor most of the planet´s biodiversity. However the microbiological component of this diversity remains relatively unexplored. Marine actinomycetes, are a robust resource of chemically prolific novelty. Producing structurally unique biological active secondary metabolites, generating a valuable source for innovative biotechnology and drug discovery[1,2]. As a consequence, the ecological role of actinomycetes and their marine ecosystems may no longer be neglected. It is crucial to move our research efforts into ocean regions for which we know little or nothing about the indigenous microbial diversity. The Portuguese Archipelago, Madeira is located in the Macaronesian Atlantic region, emerging from the African tectonic plate, found in the extreme south of the Tore-Madeira ridge, has a unique biogeography and biodiversity. These distinctive characteristics combined with the fact that Madeira have never been explored, as far as indigenous marine actinomycetes are concerned, makes it from the scientific point of view, the perfect target for our studies. From 662 marine sediment samples collected along Madeira Archipelago (Figure 1 during June of 2012, covering depths from 10-1310 m, a total of 421 actinomycete strains were isolated. In a previous study, an assemblage of 82 strains was selected for taxonomic identification, having into account representative morphological diversity characteristics of the actinomycetes, isolated from Madeira Archipelago. Based on 16S rRNA gene sequencing, it was observed that the genera Streptomyces, Micromonospora and Salinispora were predominant, 81% [3]. Additionally, in a recent study, our team selected 168 strains with Salinispora look-alike morphological features. From these 28 strains were identified as belonging to the seawater-obligate marine actinomycete genus Salinispora. Representing the first report of Salinispora spp. in the Macaronesian Atlantic Ocean

  8. Analysis and projections of physics in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Leopoldo; Zambra, Marcelo [Comision Chilena de EnergIa Nuclear, Casilla 188D, Santiago (Chile); Loewe, Marcelo [Pontificia Universidad Catolica de Chile, Facultad de Fisica, Av. Vicuna Mackenna 4860, Santiago (Chile); Gutierrez, Gonzalo; Molina, Mario [Universidad de Chile, Facultad de Ciencias, Las Palmeras 3425, Nunoa, Santiago (Chile); Barra, Felipe; Lund, Fernando [Universidad de Chile, Facultad de Ciencias Fisicas y Matematicas, Av. Blanco Encalada 2008, Santiago (Chile); Saavedra, Carlos [Universidad de Conception, Departamento de Fisica, Esteban Iturra S/N, Barrio Universitario, Conception (Chile); Haberle, Patricio [Universidad Tecnica Federico Santa MarIa, Departamento de Fisica, Av. Espana 1680, Valparaiso (Chile)], E-mail: lsoto@cchen.cl

    2008-11-01

    In the present work, an assessment of the Physics research capacity in Chile is presented. For this, the period between 2000 and June 2005 has been studied. In this period almost 200 physicists have contributed to scientific production in terms of ISI publications. Amongst these 200, {approx}160 correspond to theoretical physicists and only {approx}40 to experimental physicists; {approx}178 are men and only {approx}22 are women. A more detailed analysis shows that {approx}160 physicists have at least one appearance in ISI publications per year considering the last 3 years. Ten years ago, a similar criteria (at least one appearance per year in ISI articles, considering mobile three-year periods), the number of active physicists in the Chilean community was estimated at 70. Therefore, the Chilean active physicists' community has doubled in 10 years. There exist 20 centres in which scientific research is developed: 18 university centres, a government institute and a private institute. As regards scientific productivity, both as related to disciplines or research areas, and well as in relation to research centres, it is found that, generally, scientific production, in a particular area in Physics or in a research centre, is directly related to the number of corresponding researchers; that is to say, the percentage of the national productivity in an area or research centre corresponds to its share in the total number of physicists in the country. A geographical analysis shows that 50% of the productivity corresponds to Santiago and 50% to the rest of the country. The impact of the different funds for research is assessed, also: FONDECYT, Presidential Chairs and large projects and centres of excellence. According to Physics researchers opinion, Fondo Nacional de Ciencia y TecnologIa (FONDECYT, National Fund fro Science and Technology) has become the best instrument to support researchi activities in Chile. However, the amount of projects awarded has practically not

  9. Algorithm-Eigenvalue Estimation of Hyperspectral Wishart Covariance Matrices from a Limited Number of Samples

    Science.gov (United States)

    2015-03-01

    ALGORITHM—EIGENVALUE ESTIMATION OF HYPERSPECTRAL WISHART COVARIANCE MATRICES FROM A LIMITED NUMBER OF SAMPLES ECBC-TN-067 Avishai Ben-David...Estimation of Hyperspectral Wishart Covariance Matrices from a Limited Number of Samples 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...covariance matrices and to recompute a revised covariance matrix from the eigenvalues. The MATLAB function is an implementation of the procedure developed

  10. Large-scale portfolios using realized covariance matrix: evidence from the Japanese stock market

    OpenAIRE

    Masato Ubukata

    2009-01-01

    The objective of this paper is to examine effects of realized covariance matrix estimators based on intraday returns on large-scale minimum-variance equity portfolio optimization. We empirically assess out-of-sample performance of portfolios with different covariance matrix estimators: the realized covariance matrix estimators and Bayesian shrinkage estimators based on the past monthly and daily returns. The main results are: (1) the realized covariance matrix estimators using the past intrad...

  11. The Seismogenic Coupling Zone in Central Chile - Amphibious Experiments SPOC (Subduction Processes Off Chile)

    Science.gov (United States)

    Krawczyk, C. M.; Stiller, M.; Mechie, J.; Lueth, S.; Wigger, P.; Oncken, O.; Reichert, C.; Bataille, K.

    2003-12-01

    Nearly all interplate megathrust earthquakes occur in the seismogenic coupling zone between converging plates. In the area of the 1960 Chile earthquake (Mw = 9.5), we aim at a quantitative understanding of the seismicity and its relation to processes operating at depth and at the surface. As a first step, the offshore experiment SPOC with RV SONNE was combined with an onshore-offshore, active-passive seismic experiment between 36\\deg and 39\\deg S, crossing the rupture area of the 1960 Chile earthquake. The campaign comprised: (1) a 2-D wide-angle component recording chemical shots and airgun pulses along three consecutive E-W onshore profiles; (2) a seismic reflection experiment in the onshore-offshore transition; and (3) a 3-D component which recorded both active and passive sources. Offshore, the upper plate is split into many segments with pronounced forearc basins and a narrow accretionary wedge. A thick subduction channel seems to cause a non-frontally accreting subduction mode. Along the westernmost part of the southernmost E-W refraction seismic line, the profile spread of the active reflection seismic survey at 38\\deg 15' S was 54 km long, and also recorded the airgun shots of the marine profile with the first 18 km of its spread. Different mainly eastward dipping reflection bands are observed. Between 5-25 km depth the internal structure of the Palaeozoic accretionary wedge is described. Reflections between 16-42 km correlate with Wadati-Benioff seismicity and are interpreted as imaging the top of the downgoing plate. In the central part of the profile a break in reflectivity located below the axis of the coastal cordillera more or less coincides with the intersection between the oceanic plate and the continental Moho. This break in reflectivity also approximately correlates with the downdip end of the seismogenic plate interface as defined by geodetic modelling. These new seismic data provide the geometry of the subduction zone in the area, and hence

  12. [Measles: the disease, epidemiology, history and vaccination programs in Chile].

    Science.gov (United States)

    Delpiano, Luis; Astroza, Leonor; Toro, Jorge

    2015-08-01

    Measles, one of most important inmuno-preventable diseases, remains as a worldwide concern issue with an important morbidity and mortality. Particularly in the America region declared free of measles in 2010 by WHO, they still appear imported cases that origin outbreaks of variable magnitude in susceptible subjects usually none vaccinated which is the current situation in Santiago, the capital city of Chile. In this review we present characteristics of the etiological agent, the disease, epidemiological aspects with national historical focus, impact of immunization programs and outbreaks in Chile, in order to contribute to knowledge and management of this always present public health problem.

  13. MORTALIDAD POR ABORTO EN CHILE: ANALISIS EPIDEMIOLOGICO 1985-2000

    OpenAIRE

    Szot M,Jorge; Moreno W,Cristina

    2003-01-01

    El aborto, por su contribución a la mortalidad materna, ha sido tradicionalmente un problema de salud pública en América Latina y en Chile. En la actualidad, si bien es cierto la mortalidad por esta causa ha disminuido, la cantidad de abortos realizados permanece alta. Por este motivo, se ha querido efectuar una caracterización desde la perspectiva epidemiológica de la mortalidad por aborto ocurrido en Chile entre 1985 y 2000. Los resultados confirman la baja en la mortalidad durante el perío...

  14. ADAPTACION DE ESPECIES DE BAMBU DE CLIMA TEMPLADO EN CHILE

    OpenAIRE

    CAMPOS ROASIO, JORGE NELSON

    2005-01-01

    Hasta la fecha no se había estudiado la posibilidad de adaptar especies exóticas de las mejores especies de bambú, a las condiciones agroclimáticas de Chile con fines industriales. Sólo había pequeñas muestras de adaptación de algunas especies, las que fueron traídas a Chile básicamente con fines ornamentales. Considerando estos antecedentes y la existencia a nivel mundial de más de 1.300 especies, algunas de las cuales se desarrollan en climas templados, se desarrolló el proyecto “Adap...

  15. Chile: Political and Economic Conditions and U.S. Relations

    Science.gov (United States)

    2010-09-22

    9 Julieta Palma and Raúl Urzúa, Anti-Poverty Policies and Citizenry: The "Chile Solidario" Experience, United Nations Educational, Scientific and...heavy machinery, oil , aircraft, electrical machinery, and motor vehicles. In 2009, the United States was Chile’s top source of imports and the second...45% to 67% of the total supply between 1990 and 2006. Chile now imports about 99% of its crude oil , 72% of its natural gas, and 92% of its coal.79

  16. Chile: Inauguración de la universidad Alberto Hurtado.

    Directory of Open Access Journals (Sweden)

    Fernando Montes SJ.

    1998-03-01

    Full Text Available El 20 de octubre de 1997, se inauguró en Santiago de chile la Universidad Alberto Hurtado, dirigida por la Compañía de Jesús. En esa ocasión, su Rector, Fernando Montes S.J, pronunció su discurso inaugural en presencia del presidente chileno Eduardo Frei, del expresidente Patricio Alwing y de unas mil personas, entre senadores, diputados, figuras políticas, académicas y religiosas de Chile. Encuentro produce aquí el texto completo del discurso del Padre Montes S. J.

  17. Lorentz covariant field theory on noncommutative spacetime based on DFR algebra

    CERN Document Server

    Okumura, Y

    2003-01-01

    Lorentz covariance is the fundamental principle of every relativistic field theory which insures consistent physical descriptions. Even if the space-time is noncommutative, field theories on it should keep Lorentz covariance. In this letter, it is shown that the field theory on noncommutative spacetime is Lorentz covariant if the noncommutativity emerges from the algebra of spacetime operators described by Doplicher, Fredenhagen and Roberts.

  18. Conditioning of the stationary kriging matrices for some well-known covariance models

    Energy Technology Data Exchange (ETDEWEB)

    Posa, D. (IRMA-CNR, Bari (Italy))

    1989-10-01

    In this paper, the condition number of the stationary kriging matrix is studied for some well-known covariance models. Indeed, the robustness of the kriging weights is strongly affected by this measure. Such an analysis can justify the choice of a covariance function among other admissible models which could fit a given experimental covariance equally well.

  19. Improving on the empirical covariance matrix using truncated PCA with white noise residuals

    CERN Document Server

    Jewson, S

    2005-01-01

    The empirical covariance matrix is not necessarily the best estimator for the population covariance matrix: we describe a simple method which gives better estimates in two examples. The method models the covariance matrix using truncated PCA with white noise residuals. Jack-knife cross-validation is used to find the truncation that maximises the out-of-sample likelihood score.

  20. Electromagnetic Radiation and Equation of Motion for Really Shaped Particle -- New Covariant Formulation

    CERN Document Server

    Klacka, J

    2001-01-01

    Relativistically covariant form of equation of motion for real particle (body) under the action of electromagnetic radiation is derived. Equation of motion in the proper frame of the particle uses the radiation pressure cross section 3 $\\times$ 3 matrix. Obtained covariant equation of motion is compared with another covariant equation of motion which was presented more than one year ago.