578 research outputs found
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The Use of Unprocessed Cotton Gin Trash by Growing and Fattening Steers
This item is part of the Agricultural Experiment Station archive. It was digitized from a physical copy provided by the University Libraries at the University of Arizona. For more information, please email CALS Publications at [email protected]
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Case Studies V: Fish Migration River: Monitoring Plan after Construction
Stability of Localized Wave Fronts in Bistable Systems
Localized wave fronts are a fundamental feature of biological systems from cell biology to ecology. Here, we study a broad class of bistable models subject to self-activation, degradation, and spatially inhomogeneous activating agents. We determine the conditions under which wave-front localization is possible and analyze the stability thereof with respect to extrinsic perturbations and internal noise. It is found that stability is enhanced upon regulating a positional signal and, surprisingly, also for a low degree of binding cooperativity. We further show a contrasting impact of self-activation to the stability of these two sources of destabilization. DOI: 10.1103/PhysRevLett.110.03810
Anticipation of distress after discontinuation of mechanical ventilation in the ICU at the end of life
Background: A considerable number of patients admitted to the intensive care unit (ICU) die following withdrawal of mechanical ventilation. After discontinuation of ventilation without proper preparation, excessive respiratory secretion is common, resulting in a 'death rattle'. Post-extubation stridor can give rise to the relatives' perception that the patient is choking and suffering. Existing protocols lack adequate anticipatory preparation to respond to all distressing symptoms. Methods: We analyzed existing treatment strategies in distressing symptoms after discontinuation of mechanical ventilation. Conclusion: The actual period of discontinuation of mechanical ventilation can be very short, but thoughtful anticipation of distressing symptoms takes time. There is an ethical responsibility to anticipate and treat (iatrogenic) symptoms such as pain, dyspnea-associated respiratory distress, anxiety, delirium, post-extubation stridor, and excessive broncho-pulmonary secretions. This makes withdrawal of mechanical ventilation in ICU patients a thoughtful process, taking palliative actions instead of fast terminal actions. We developed a flowchart covering all possible distressi
Observational signatures of a kink-unstable coronal flux rope using Hinode/EIS
The signatures of energy release and energy transport for a kink-unstable coronal flux rope are investigated via forward modelling. Synthetic intensity and Doppler maps are generated from a 3D numerical simulation. The CHIANTI database is used to compute intensities for three Hinode/EIS emission lines that cover the thermal range of the loop. The intensities and Doppler velocities at simulation resolution are spatially degraded to the Hinode/EIS pixel size (1′′), convolved using a Gaussian point-spread function (3′′), and exposed for a characteristic time of 50 seconds. The synthetic images generated for rasters (moving slit) and sit-and-stare stationary slit) are analysed to find the signatures of the twisted flux and the associated instability. We find that there are several qualities of a kink-unstable coronal flux rope that can be detected observationally using Hinode/EIS, namely the growth of the loop radius, the increase in intensity towards the radial edge of the loop, and the Doppler velocity following an internal twisted magnetic field line. However, EIS cannot resolve the small, transient features present in the simulation, such as sites of small-scale reconnection (e.g. nanoflares)
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Do silver eel find their way along sluices and pumping stations in highly regulated water systems
In order to quantify abundance, to study migration behaviour and to evaluate passage success along a 26 long canal (North Sea Canal) in the Netherlands, a telemetry experiment was carried out by tagging 2630 silver eel (Anguilla anguilla).
A network of 64 VEMCO receivers was used to detect movement of silver eel tagged with V9 (n=280), V9P (n=50) acoustics transmitters and 32mm HDX PITtag. In addition, 2300 silver eel were tagged with 32mm HDX pittags for mark recapture purposes and fish pass evaluation. Fisherman along the canal were equipped with manual PITtag readers in case of a recapture during (commercial) fisheries.
Within this study eleven locations were selected to evaluate escapement from of freshwater polder systems into the canal and eventually towards the North Sea. Individual variation in observed patterns was large and not all routes were efficient in terms of energy used. Some eel swam up and down the canal before reaching the sea, while others (groups) did not succeed in escaping at all, showing a large barrier effect. Also, some eel swam back towards the polder using sluices and eel seemed to prefer the main water flow instead of a fish passage along a pumping station or migration facilities in sluices. Successful escapement showed part of the silver eel were detected in the Lifewatch network along the Belgian coast. Based on recapture assessment at least 110.000 silver eel successfully migrated along the sluices of Ijmuiden.
This research was funded by a unique collaboration of different water boards and partners along the canal
International Space Station Major Constituent Analyzer On-Orbit Performance
The Major Constituent Analyzer (MCA) is an integral part of the International Space Station (ISS) Environmental Control and Life Support System (ECLSS). The MCA is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor. These gases are sampled continuously and automatically in all United States On-Orbit Segment (USOS) modules via the Sample Distribution System (SDS). The MCA is the primary tool for management of atmosphere constituents and is therefore critical for ensuring a habitable ISS environment during both nominal ISS operations and campout EVA preparation in the Airlock. The MCA has been in operation in the US Destiny Laboratory Module for over 10 years, and a second MCA has been delivered to the ISS for Node 3 operation. This paper discusses the performance of the MCA over the two past year, with particular attention to lessons learned regarding the operational life of critical components. Recent data have helped drive design upgrades for a new set of orbit-replaceable units (ORUs) currently in production. Several ORU upgrades are expected to increase expected lifetimes and reliability
Tuinarcheologisch onderzoek in de binnentuin van het kasteel van Gaasbeek te Lennik (Vl.- Brabant). Eindverslag van een opgraving vanuit wetenschappelijke vraagstelling
De opgraving met wetenschappelijke vraagstelling in de in de late 19de eeuw aangelegde neorenaissance binnentuin van het kasteel van Gaasbeek had tot doel na te gaan of er nog sporen aanwezig waren van de oorspronkelijke aanleg. Hiervoor werden in samenspraak met collegas vijf werkputjes op cruciale plaatsen uitgezet en opgegraven en gerichte onderzoeksvragen opgesteld
International Space Station Major Constituent Analyzer On-Orbit Performance
The Major Constituent Analyzer is a mass spectrometer based system that measures the major atmospheric constituents on the International Space Station. A number of limited-life components require periodic change-out, including the ORU 02 analyzer and the ORU 08 Verification Gas Assembly. Improvements to ion pump operation and ion source tuning have improved lifetime performance of the current ORU 02 design. The most recent ORU 02 analyzer assemblies, as well as ORU 08, have operated nominally. For ORU 02, the ion source filaments and ion pump lifetime continue to be key determinants of MCA performance and logistical support. Monitoring several key parameters provides the capacity to monitor ORU health and properly anticipate end of life
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