9 research outputs found
TNOs are cool: a survey of the transneptunian region
Over one thousand objects have so far been discovered orbiting beyond Neptune. These trans-Neptunian objects (TNOs) represent the primitive remnants of the planetesimal disk from which the planets formed and are perhaps analogous to the unseen dust parent-bodies in debris disks observed around other main-sequence stars. The dynamical and physical properties of these bodies provide unique and important constraints on formation and evolution models of the Solar System. While the dynamical architecture in this region (also known as the Kuiper Belt) is becoming relatively clear, the physical properties of the objects are still largely unexplored. In particular, fundamental parameters such as size, albedo, density and thermal properties are difficult to measure. Measurements of thermal emission, which peaks at far-IR wavelengths, offer the best means available to determine the physical properties. While Spitzer has provided some results, notably revealing a large albedo diversity in this population, the increased sensitivity of Herschel and its superior wavelength coverage should permit profound advances in the field. Within our accepted project we propose to perform radiometric measurements of 139 objects, including 25 known multiple systems. When combined with measurements of the dust population beyond Neptune (e.g. from the New Horizons mission to Pluto), our results will provide a benchmark for understanding the Solar debris disk, and extra-solar ones as well
Response of the beetle Hylastinus obscurus Marsham (Coleoptera : Scolytidae) to red clover (Trifolium pratense L.) volatiles in a laboratory olfactometer
Ramirez, C.C. Centro de InvestigaciĂłn en BiotecnologĂa Silvoagropecuaria, Instituto de BiologĂa Vegetal y BiotecnologĂa. Universidad de Talca,Talca, Chile.The response of field-collected Hylastinus obscurus Marsham (Coleoptera: Scolytidae) to volatiles from Trifolium pratense L. of different ages was studied in a four-arm olfactometer. Volatiles from 1.5-, 2-, and 2.5-yr-old plants were more attractive than volatiles from 1-, 3-, and 3.5-yr-old plants. Two-year-old plants were preferred during winter, spring, and summer. One-year-old plants were not preferred in their early stages, but preference increased as they aged. Volatiles from 3-yr-old plants were never preferred. The essential oils obtained from 2-yr-old T pratense elicited an attraction response from H. obscurus. Beetle response is discussed in relation to host-locating behavior
Pneumoperitoneum Post-Fluoroscopic Percutaneous Gastrojejunostomy Insertion: Computed Tomography and Clinical Evaluation
Stochastic Modeling of Multiwavelength Variability of the Classical BL Lac Object OJ 287 on Timescales Ranging from Decades to Hours
We present the results of our power spectral density analysis for the BL Lac object OJ 287, utilizing the Fermi-LAT survey at high-energy Îł-rays, Swift-XRT in X-rays, several ground-based telescopes and the Kepler satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time autoregressive moving average (CARMA) processes. Owing to the inclusion of the Kepler data, we were able to construct for the first time the optical variability power spectrum of a blazar without any gaps across âŒ6 dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the Îł-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the Fermi-LAT data, corresponding to âŒ150 days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise. © 2018. The American Astronomical Society. All rights reserved.
Acute heart failure congestion and perfusion status â impact of the clinical classification on in-hospital and long-term outcomes; insights from the ESC-EORP-HFA Heart Failure Long-Term Registry
Aims: Classification of acute heart failure (AHF) patients into four clinical profiles defined by evidence of congestion and perfusion is advocated by the 2016 European Society of Cardiology (ESC)guidelines. Based on the ESC-EORP-HFA Heart Failure Long-Term Registry, we compared differences in baseline characteristics, in-hospital management and outcomes among congestion/perfusion profiles using this classification. Methods and results: We included 7865 AHF patients classified at admission as: âdry-warmâ (9.9%), âwet-warmâ (69.9%), âwet-coldâ (19.8%) and âdry-coldâ (0.4%). These groups differed significantly in terms of baseline characteristics, in-hospital management and outcomes. In-hospital mortality was 2.0% in âdry-warmâ, 3.8% in âwet-warmâ, 9.1% in âdry-coldâ and 12.1% in âwet-coldâ patients. Based on clinical classification at admission, the adjusted hazard ratios (95% confidence interval) for 1-year mortality were: âwet-warmâ vs. âdry-warmâ 1.78 (1.43â2.21) and âwet-coldâ vs. âwet-warmâ 1.33 (1.19â1.48). For profiles resulting from discharge classification, the adjusted hazard ratios (95% confidence interval) for 1-year mortality were: âwet-warmâ vs. âdry-warmâ 1.46 (1.31â1.63) and âwet-coldâ vs. âwet-warmâ 2.20 (1.89â2.56). Among patients discharged alive, 30.9% had residual congestion, and these patients had higher 1-year mortality compared to patients discharged without congestion (28.0 vs. 18.5%). Tricuspid regurgitation, diabetes, anaemia and high New York Heart Association class were independently associated with higher risk of congestion at discharge, while beta-blockers at admission, de novo heart failure, or any cardiovascular procedure during hospitalization were associated with lower risk of residual congestion. Conclusion: Classification based on congestion/perfusion status provides clinically relevant information at hospital admission and discharge. A better understanding of the clinical course of the two entities could play an important role towards the implementation of targeted strategies that may improve outcomes. © 2019 The Authors. European Journal of Heart Failure © 2019 European Society of Cardiolog