Fractional isoperimetric Noether's theorem in the Riemann-Liouville sense

We prove Noether-type theorems for fractional isoperimetric variational problems with Riemann-Liouville derivatives. Both Lagrangian and Hamiltonian formulations are obtained. Illustrative examples, in the fractional context of the calculus of variations, are discussed.Comment: Submitted 12-Oct-2012; revised 05-Jan-2013; accepted 23-Jan-2013; for publication in Reports on Mathematical Physics. arXiv admin note: substantial text overlap with arXiv:1001.450

Fractional Noether's theorem in the Riesz-Caputo sense

We prove a Noether's theorem for fractional variational problems with Riesz-Caputo derivatives. Both Lagrangian and Hamiltonian formulations are obtained. Illustrative examples in the fractional context of the calculus of variations and optimal control are given.Comment: Accepted (25/Jan/2010) for publication in Applied Mathematics and Computatio

A Formulation of Noether's Theorem for Fractional Problems of the Calculus of Variations

Fractional (or non-integer) differentiation is an important concept both from theoretical and applicational points of view. The study of problems of the calculus of variations with fractional derivatives is a rather recent subject, the main result being the fractional necessary optimality condition of Euler-Lagrange obtained in 2002. Here we use the notion of Euler-Lagrange fractional extremal to prove a Noether-type theorem. For that we propose a generalization of the classical concept of conservation law, introducing an appropriate fractional operator.Comment: Accepted for publication in the Journal of Mathematical Analysis and Application

Noether's theorem for non-smooth extremals of variational problems with time delay

We obtain a non-smooth extension of Noether's symmetry theorem for variational problems with delayed arguments. The result is proved to be valid in the class of Lipschitz functions, as long as the delayed Euler-Lagrange extremals are restricted to those that satisfy the DuBois-Reymond necessary optimality condition. The important case of delayed variational problems with higher order derivatives is considered as well. © 2013 Taylor & Francis

Esquistossomose: reprodução e expansão da endemia no Estado de Pernambuco no Brasil Schistosomiasis: reproduction and expansion of the endemic region in Brazil

A esquistossomose continua a ser um problema de saúde pública no Nordeste do Brasil embora o emprego, em larga escala, da quimioterapia venha sendo apontado como um dos fatores responsáveis pela redução das formas graves. O Estado de Pernambuco vem apresentando taxas crescentes de infecção humana para esquistossomose com perfil epidemiológico de prevalências crônicas (até 80%) na região rural e casos recentes de infecção aguda no litoral. Discute-se a reprodução e expansão da esquistossomose a partir de uma concepção estrutural e histórica de causas, onde se inserem fatores não só de ordem biológica mas também sociais, políticos e culturais que vêm contribuindo para a formação dos quadros endêmicos: a forma de ocupação e do uso da terra, desemprego, desnutrição, migração e outros. Questionam-se as crescentes dificuldades para o controle da doença e o papel da investigação epidemiológica na compreensão da essência social do processo saúde/doença.<br>Schistosomiasis mansoni can be considered an important public health problem in Northeastern Brazil, in spite of the reduction in the prevalence of the hepatosplenic clinical forms which have been attributed to the large scale use of chemotherapy in this country. However, the rise in the prevalence rates and the spread of this endemic disease to new areas show that schistosomiasis is assuming its must cruel expression: less lethal but more greatly incapacitating in terms of irreversible physical and moral damage to human beings. The state of Pernambuco presents growing rates for schistosomiasis infection in humans. The epidemiological profile of this disease displays high and consistent prevalence rates (up to 80%) in rural areas, and new cases of acute infection on the coast, where schistosomiasis has recently been introduced. The reproduction and expansion of this endemic disease can be better understood on the basic of a conception of structural and historical causation. The disease construction process should be reconstructed in the light of biological as well as the social, political and cultural factors which are jointly responsible for the present endemic situation. Within that frame work, the historical and socio-economic features that interact with the parasite and give rise to the present proportions of the schistosomiasis epidemic in Pernambuco are discussed. The mode of occupation and use of the land, unemployment, under-nutrition, migration, etc., raise the question of the growing difficulties confronting the control of the disease, both in rural areas where populations are extremely mobile as well as in the poorly organized urban population. Epidemiological investigation is fulfithing its role in its attenpts to understand the complex relationships of an intrinsecally social nature of the health/disease process between health problems and the quality of life for the purpose of producing consistent disease control models

SDSS-III : massive spectroscopic surveys of the distant universe, the Milk Way, and extra-solar planetary systems

Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS Data Release 8 (DR8), which was made public in 2011 January and includes SDSS-I and SDSS-II images and spectra reprocessed with the latest pipelines and calibrations produced for the SDSS-III investigations. This paper presents an overview of the four surveys that comprise SDSS-III. The Baryon Oscillation Spectroscopic Survey will measure redshifts of 1.5 million massive galaxies and Lyα forest spectra of 150,000 quasars, using the baryon acoustic oscillation feature of large-scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z < 0.7 and at z ≈ 2.5. SEGUE- 2, an already completed SDSS-III survey that is the continuation of the SDSS-II Sloan Extension for Galactic Understanding and Exploration (SEGUE), measured medium-resolution (R = λ/Δλ ≈ 1800) optical spectra of 118,000 stars in a variety of target categories, probing chemical evolution, stellar kinematics and substructure, and the mass profile of the dark matter halo from the solar neighborhood to distances of 100 kpc. APOGEE, the Apache Point Observatory Galactic Evolution Experiment, will obtain high-resolution (R ≈ 30,000), high signal-to-noise ratio (S/N 100 per resolution element), H-band (1.51μm < λ < 1.70μm) spectra of 105 evolved, late-type stars, measuring separate abundances for ∼15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. The Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10–40ms−1, ∼24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of 2011 January, SDSS-III has obtained spectra of more than 240,000 galaxies, 29,000 z 2.2 quasars, and 140,000 stars, including 74,000 velocity measurements of 2580 stars for MARVELS

The BINGO project - II. Instrument description

International audienceContext. The measurement of diffuse 21-cm radiation from the hyperfine transition of neutral hydrogen (H I signal) in different redshifts is an important tool for modern cosmology. However, detecting this faint signal with non-cryogenic receivers in single-dish telescopes is a challenging task. The BINGO (Baryon Acoustic Oscillations from Integrated Neutral Gas Observations) radio telescope is an instrument designed to detect baryonic acoustic oscillations (BAOs) in the cosmological H I signal, in the redshift interval 0.127 ≤ z ≤ 0.449.Aims. This paper describes the BINGO radio telescope, including the current status of the optics, receiver, observational strategy, calibration, and the site.Methods. BINGO has been carefully designed to minimize systematics, being a transit instrument with no moving dishes and 28 horns operating in the frequency range 980 ≤ ν ≤ 1260 MHz. Comprehensive laboratory tests were conducted for many of the BINGO subsystems and the prototypes of the receiver chain, horn, polarizer, magic tees, and transitions have been successfully tested between 2018–2020. The survey was designed to cover ∼13% of the sky, with the primary mirror pointing at declination δ = −15°. The telescope will see an instantaneous declination strip of 14.75°.Results. The results of the prototype tests closely meet those obtained during the modeling process, suggesting BINGO will perform according to our expectations. After one year of observations with a 60% duty cycle and 28 horns, BINGO should achieve an expected sensitivity of 102 μK per 9.33 MHz frequency channel, one polarization, and be able to measure the H I power spectrum in a competitive time frame.Key words: instrumentation: detectors / methods: observationa