28 research outputs found
Upper limits for PH3 and H2S in Titan's Atmosphere from Cassini CIRS
We have searched for the presence of simple P and S-bearing molecules in
Titan's atmosphere, by looking for the characteristic signatures of phosphine
and hydrogen sulfide in infrared spectra obtained by Cassini CIRS. As a result
we have placed the first upper limits on the stratospheric abundances, which
are 1 ppb (PH3) and 330 ppb (H2S), at the 2-sigma significance level.Comment: 12 pages text, 1 table, 2 figure
Photochemical Haze Formation in the Atmospheres of Super-Earths and Mini-Neptunes
UV (ultraviolet) radiation can induce photochemical processes in the atmospheres of exoplanet and produce haze particles. Recent transmission spectra of super-Earths and mini-Neptunes have demonstrated the possibility that exoplanets have haze/cloud layers at high altitudes in their atmospheres. Haze particles play an important role in planetary atmospheres because they affect the chemistry, dynamics, and radiation flux in planetary atmospheres, and may provide a source of organic material to the surface which may impact the origin or evolution of life. However, very little information is known about photochemical processes in cool, high-metallicity exoplanetary atmospheres. We present here photochemical haze formation in laboratory simulation experiments with UV radiation; we explored temperatures ranging from 300 to 600 degrees Kelvin and a range of atmospheric metallicities (100 times, 1000 times, and 10000 times solar metallicity). We find that photochemical hazes are generated in all simulated atmospheres, but the haze production rates appear to be temperature dependent: the particles produced in each metallicity group decrease as the temperature increases. The images taken with an atomic force microscope (AFM) show that the particle size (15 nanometers to 190 nanometers) varies with temperature and metallicity. Our results provide useful laboratory data on the photochemical haze formation and particle properties, which can serve as critical inputs for exoplanet atmosphere modeling, and guide future observations of exoplanets with the Transiting Exoplanet Survey Satellite (TESS), the James Webb Space Telescope (JWST), and the Wide-Field Infrared Survey Telescope (WFIRST)
Roles of NMDA and dopamine in food-foraging decision-making strategies of rats in the social setting
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Neural network based system for damage identification and location in structural and mechanical systems
This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Recent advances in wireless, remotely monitored data acquisition systems coupled with the development of vibration-based damage detection algorithms make the possibility of self- or remotely-monitored structures and mechanical systems appear to be within the capabilities of current technology. However, before such a system can be relied upon to perform this monitoring, the variability of the vibration properties that are the basis for the damage detection algorithm must be understood and quantified. This understanding is necessary so that the artificial intelligence/expert system that is employed to discriminate when changes in modal properties are indicative of damage will not yield false indications of damage. To this end, this project has focused on developing statistical methods for quantifying variability in identified vibration proper ties of structural and mechanical systems
Variation in care practices across pediatric acute care cardiology units: Results of the Pediatric Acute Care Cardiology Collaborative (PAC(3)) hospital survey
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Intensive Care Unit and Acute Care Unit Length of Stay After Congenital Heart Surgery
BackgroundPostoperative length of stay (LOS) is an important quality metric and is known to vary widely across hospitals after congenital heart surgery. Whether this variability is explained by factors associated with the intensive care unit (ICU) or acute care unit (ACU) remains unclear. We evaluated the relationship between ICU and ACU LOS and the impact of ACU characteristics on postoperative LOS.MethodsHospitalizations for congenital heart surgery within the Pediatric Cardiac Critical Care Consortium (PC4) registry (August 2014 to February 2018) were included. Models were developed for ICU, ACU, and postoperative LOS by adjusting for differences in case-mix across hospitals. PC4 hospitals participating in the Pediatric Acute Care Cardiology Collaborative (PAC3) were also surveyed on ACU organizational factors and practice patterns.ResultsOverall, 19,674 hospitalizations across 27 hospitals were included. There was significant variation in ICU and ACU LOS. Postperative LOS appeared to be most closely related to ICU LOS; 75% (6 of 8) of hospitals with shorter than expected postoperative LOS also had shorter than expected ICU LOS. A clear relationship between postoperative and ACU LOS was not observed. Hospitals with an ACU able to provide higher-acuity care as indexed according to the PAC3 survey were more likely to have shorter postoperative LOS (P < .01).ConclusionsFor hospitals that achieve shorter than expected postoperative LOS after congenital heart surgery, ICU LOS appears to be the primary driver. Higher-acuity resources in the ACU may be an important factor facilitating earlier transfer from the ICU. These data are key to informing quality improvement initiatives geared toward reducing postoperative LOS
Der Einfluss moderner Geraetegenerationen der Informations- und Kommunikationstechnik auf den Energieverbrauch in Deutschland bis zum Jahr 2010 - Moeglichkeiten zur Erhoehung der Energieeffizienz und zur Energieeinsparung in diesen Bereichen Abschlussbericht. Kurzfassung des Abschlussberichts. Summary of the final report. Anhang zum Abschlussbericht
Fuer das Jahr 2001 wurde in dieser Untersuchung ein den IuK-Endgeraeten in Haushalten und Bueros und der zugehoerigen Infrastruktur zuzurechnender Strombedarf in Hoehe von 38 TWh ermittelt. Dies entspricht einem Anteil von knapp 8% am gesamten Stromverbrauch der Endverbrauchssektoren in Deutschland (AGEB 2002). Rund 50% des Strombedarfs entfallen dabei auf die Haushalts-Endgeraete, weitere gut 20% auf die Buero-Endgeraete, die restlichen rund 30% auf die dafuer erforderliche Infrastruktur. Bis 2010 wird mit einem deutlichen Anstieg des Strombedarfs um 45% auf 55,4 TWh gerechnet, der vor allem durch die zunehmende Bedeutung der IuK-Infrastruktur verursacht wird. Da die meisten der im Bestand deutlich wachsenden Geraete und Anlagen der IuK-Infrastruktur wie Server oder Mobilfunkanlagen dauerhaft in Betrieb sind, faellt damit auch der Verbrauchszuwachs im Normalbetrieb am staerksten aus. Der Verbrauch im Bereitschaftsbetrieb zeigt vor allem bis Mitte des Jahrzehnts noch eine steigende Tendenz, waehrend er im Schein-Aus-Zustand ruecklaeufig ist. Dies ist allerdings weniger auf Effizienzanstrengungen als auf eine erwartete Substitution des Schein-Aus- durch den Bereitschaftsbetrieb (insbesondere bei Fernsehern) zurueckzufuehren. (orig.)For 2001, this study ascertained an electricity demand of 38 TWh for ICT end-use appliances in households and offices and their associated infrastructure. This corresponds to a share of almost 8% of the total electricity consumption of final consumption sectors in Germany (AGEB 2002). About 50% of the power demand are accounted for by household end-use appliances, a further 20% by office end-use appliances, the remaining 30% by the infrastructure required. A clear increase in the power demand by 45% up to 55.4 TWh is anticipated up to 2010 which is primarily caused by the increasing significance of ICT infrastructure. The stock of appliances and systems of ICT infrastructure will grow noticeably and since these devices, such as servers or mobile communications systems, are continuously operated, the consumption growth in normal mode is the strongest. The consumption in standby mode shows an increasing tendency, most notably up to the middle of the decade, whereas it decreases in off-mode. However, this has less to do with efforts for greater efficiency and more to do with the expected substitution of the off- by the standby mode (especially in televisions). (orig.)Published in 4 volumesSIGLEAvailable from TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Wirtschaft und Arbeit (BMWA), Berlin (Germany)DEGerman