Equinococosis neotropical en Cuniculus paca (Linnaeus 1766) y Dasypus novemcinctus (Linnaeus 1758), en la cuenca alta del Río Itaya, Perú

Echinococcus vogeli originates neotropical polychistic echinococcosis, an emerging zoonotic disease in tropical countries of Central and South America. Its life cycle is adapted to a mandatory relationship between the bush dog (Speothos venaticus) and one of its main prey, the paca (Cuniculus paca), which is, in turn, one of the most consumed species as a source of animal protein in the Peruvian Amazon. The aim of this work was to evaluate the frequency of E. vogeli in pacas hunted for personal consumption by inhabitants in the high basin of the Itaya River. During 2016-2017, subsistence hunters from the communities of Melitón Carbajal, Luz del Oriente, 28 de Enero and Nueva Villa Belén collected liver and lungs of 36 pacas and the liver of a nine-banded armadillo (Dasypus novemcinctus). These organs were analyzed by parasitological, including macroscopic, microscopic-morphometric analysis. The 13.5% (5/37) of the wild mammals collected (paca n=4; nine-banded armadillo n=1) presented polycystic masses in the liver, with rostral hooks of protocystic scolices compatible with E. vogeli. This work contributes to the ecoepidemiological knowledge of new records on the distribution of E. vogeli and confirms the first record of E. vogeli in the nine-banded armadillo in the Peruvian Amazon, reinforcing the need to raise awareness, prevent, monitor, control and expand the search for neotropical echinococcosis and other zoonoses in wildlife and human populations in coexistence, from the “One Health” approach.Echinococcus vogeli origina la Equinococosis Neotropical Poliquística, enfermedad zoonótica emergente en países tropicales de Centro y Sur América. Su ciclo natural está adaptado a una relación predador–presa representado principalmente por el perro de monte (Speothos venaticus) y el majaz (Cuniculus paca), que es una de las especies silvestres más consumidas en la Amazonia. El objetivo de este trabajo fue evaluar la frecuencia de E. vogeli en majaces cazados para consumo personal por pobladores de la cuenca alta del Río Itaya, en la Amazonía peruana. Durante el periodo 2016-2017, cazadores de subsistencia de las comunidades de Melitón Carbajal, Luz del Oriente, 28 de Enero y Nueva Villa Belén realizaron la colecta de hígados y pulmones de 36 majaces y el hígado de un armadillo de nueve bandas, (Dasypus novemcinctus). Se realizaron análisis parasitológicos, que incluyó descripciones macroscópicas, microscópicas y morfometría. El 13,5% (5/37) de los mamíferos silvestres colectados (majaz n=4; armadillo de nueve bandas n=1) presentaron masas poliquísticas en hígado, con ganchos rostelares de protoescólices compatibles con E. vogeli. Este trabajo aporta al conocimiento ecoepidemiológico de nuevos registros sobre la distribución de E. vogeli y confirma el primer registro de E. vogeli en armadillo de nueve bandas en la Amazonia peruana, reforzando la necesidad de concientizar, prevenir, monitorear, controlar y ampliar la búsqueda de la equinococosis neotropical y otras zoonosis en fauna silvestre y en poblaciones humanas en coexistencia, desde el enfoque de “Una Salud”

Recent developments in planet migration theory

Planetary migration is the process by which a forming planet undergoes a drift of its semi-major axis caused by the tidal interaction with its parent protoplanetary disc. One of the key quantities to assess the migration of embedded planets is the tidal torque between the disc and planet, which has two components: the Lindblad torque and the corotation torque. We review the latest results on both torque components for planets on circular orbits, with a special emphasis on the various processes that give rise to additional, large components of the corotation torque, and those contributing to the saturation of this torque. These additional components of the corotation torque could help address the shortcomings that have recently been exposed by models of planet population syntheses. We also review recent results concerning the migration of giant planets that carve gaps in the disc (type II migration) and the migration of sub-giant planets that open partial gaps in massive discs (type III migration).Comment: 52 pages, 18 figures. Review article to be published in "Tidal effects in Astronomy and Astrophysics", Lecture Notes in Physic

Giant Planet Formation and Migration

© 2018, The Author(s). Planets form in circumstellar discs around young stars. Starting with sub-micron sized dust particles, giant planet formation is all about growing 14 orders of magnitude in size. It has become increasingly clear over the past decades that during all stages of giant planet formation, the building blocks are extremely mobile and can change their semimajor axis by substantial amounts. In this chapter, we aim to give a basic overview of the physical processes thought to govern giant planet formation and migration, and to highlight possible links to water delivery.S.-J. Paardekooper is supported by a Royal Society University Research Fellowship. A. Johansen is supported by the Knut and Alice Wallenberg Foundation, the Swedish Research Council (grant 2014-5775) and the European Research Council (ERC Starting Grant 278675-PEBBLE2PLANET)

The Theory of Brown Dwarfs and Extrasolar Giant Planets

Straddling the traditional realms of the planets and the stars, objects below the edge of the main sequence have such unique properties, and are being discovered in such quantities, that one can rightly claim that a new field at the interface of planetary science and and astronomy is being born. In this review, we explore the essential elements of the theory of brown dwarfs and giant planets, as well as of the new spectroscopic classes L and T. To this end, we describe their evolution, spectra, atmospheric compositions, chemistry, physics, and nuclear phases and explain the basic systematics of substellar-mass objects across three orders of magnitude in both mass and age and a factor of 30 in effective temperature. Moreover, we discuss the distinctive features of those extrasolar giant planets that are irradiated by a central primary, in particular their reflection spectra, albedos, and transits. Aspects of the latest theory of Jupiter and Saturn are also presented. Throughout, we highlight the effects of condensates, clouds, molecular abundances, and molecular/atomic opacities in brown dwarf and giant planet atmospheres and summarize the resulting spectral diagnostics. Where possible, the theory is put in its current observational context.Comment: 67 pages (including 36 figures), RMP RevTeX LaTeX, accepted for publication in the Reviews of Modern Physics. 30 figures are color. Most of the figures are in GIF format to reduce the overall size. The full version with figures can also be found at: http://jupiter.as.arizona.edu/~burrows/papers/rm

Association of Immunosuppression and Human Immunodeficiency Virus (HIV) Viremia with Anal Cancer Risk in Persons Living with HIV in the United States and Canada

Background: People living with human immunodeficiency virus (HIV; PLWH) have a markedly elevated anal cancer risk, largely due to loss of immunoregulatory control of oncogenic human papillomavirus infection. To better understand anal cancer development and prevention, we determined whether recent, past, cumulative, or nadir/peak CD4+ T-cell count (CD4) and/or HIV-1 RNA level (HIV RNA) best predict anal cancer risk. Methods: We studied 102 777 PLWH during 1996-2014 from 21 cohorts participating in the North American AIDS Cohort Collaboration on Research and Design. Using demographics-adjusted, cohort-stratified Cox models, we assessed associations between anal cancer risk and various time-updated CD4 and HIV RNA measures, including cumulative and nadir/peak measures during prespecified moving time windows. We compared models using the Akaike information criterion. Results: Cumulative and nadir/peak CD4 or HIV RNA measures from approximately 8.5 to 4.5 years in the past were generally better predictors for anal cancer risk than their corresponding more recent measures. However, the best model included CD4 nadir (ie, the lowest CD4) from approximately 8.5 years to 6 months in the past (hazard ratio [HR] for <50 vs ≥500 cells/μL, 13.4; 95% confidence interval [CI], 3.5-51.0) and proportion of time CD4 <200 cells/μL from approximately 8.5 to 4.5 years in the past (a cumulative measure; HR for 100% vs 0%, 3.1; 95% CI, 1.5-6.6). Conclusions: Our results are consistent with anal cancer promotion by severe, prolonged HIV-induced immunosuppression. Nadir and cumulative CD4 may represent useful markers for identifying PLWH at higher anal cancer risk