23,762 research outputs found
Scintillation detector for carbon-14
Detector consists of plastic, cylindrical double-wall scintillation cell, which is filled with gas to be analyzed. Thin, inner cell wall is isolated optically from outer (guard) scintillator wall by evaporated-aluminum coating. Bonding technique provides mechanical support to cell wall when device is exposed to high temperatures
Development of S-13G-type coatings as engineering materials Final report, 1 Sep. 1966 - 31 Aug. 1968
S-13G type thermal control coatings for space application
Stratospheric CCN sampling program
Two one liter grab samples of stratospheric aerosol were returned from each of six U-2 sampling missions. Cloud condensation nuclei (CCN) spectra from each sample were obtained. Interest was centered on the effects of volcanic activity. Spurious particle generation was found to be a serious problem in container 9 LFT and a much smaller problem in container 9 RT. Initial studies of an option for improved sample containers and values were completed. A CCN spectrometer, able to operate at an internal pressure of 300 mb, was designed
Development of space stable thermal control coatings Triannual report, Mar. 1 - Jul. 31, 1967
Ultraviolet irradiation effects on space stable thermal control zinc coating
The behavior of several white pigments as determined by in situ reflectance measurements of irradiated specimens
Reflectance measurements of irradiated specimens of zinc oxide and zinc orthotitanate white pigment material
Design, fabrication and delivery of a prototype saturator for ACPL
The design configuration and performance characteristics of a saturator developed to provide ground-based simulation for some of the experiments for ACPL-1 first flights of Spacelab are described, some difficulties encountered with the apparatus are discussed, and recommendations concerning testing of this type of instrument are presented. The saturators provide a means of accurately fixing the water vapor mixing ratio of an aerosol sample. Dew point temperatures from almost freezing to ambient room temperatures can be attained with high precision. The instruments can accommodate aerosol flow rates approaching 1000 cc/s. Provisions were made to inject aerosols upstream of these saturators, although downstream injection can be accomplished as well. A device of this type will be used in the ACPL-1 to condition various aerosols delivered concurrently to a CFD, expansion chamber, and static diffusion chamber used in zero gravity cloud-forming experiments. The saturator was designed to meet the requirements projected for the flight instrument
Characterization of Bose-Hubbard Models with Quantum Non-demolition Measurements
We propose a scheme for the detection of quantum phase transitions in the 1D
Bose-Hubbard (BH) and 1D Extended Bose-Hubbard (EBH) models, using the
non-demolition measurement technique of quantum polarization spectroscopy. We
use collective measurements of the effective total angular momentum of a
particular spatial mode to characterise the Mott insulator to superfluid phase
transition in the BH model, and the transition to a density wave state in the
EBH model. We extend the application of collective measurements to the ground
states at various deformations of a super-lattice potential.Comment: 8 pages, 9 figures; published version in PRA, Editors' Suggestio
When is parenteral nutrition indicated in the hospitalized, acutely ill patient?
PURPOSE OF REVIEW
The current review discusses current practices regarding appropriate indications for parenteral nutrition in acutely ill hospitalized patients. We address-specific indications for parenteral nutrition in the perioperative period, and in inflammatory bowel disease, oncology, hepatobiliary, critical care and end-stage renal disease patients.
RECENT FINDINGS
Acutely ill hospitalized patients can develop intestinal failure requiring parenteral nutrition. Recent studies have provided insight into the main indications. The most common indications for inpatient parenteral nutrition include postsurgical complications, including prolonged ileus, sepsis, fistula and leaks, and bowel obstruction, predominantly malignant. Severe or complicated inflammatory bowel disease and cancer treatment-related mucosal enteropathies (mucositis, enterocolitis, gut graft-versus-host disease) are the next commonest indications. Less frequent indications are primary motility disorders and inability to secure enteral access for enteral nutrition. Gastrointestinal failure of the intensive care patient is a separate entity resulting from multiple mechanisms, including an enteropathy and dysmotility.
SUMMARY
Despite the wider availability of nutrition support teams, use of parenteral nutrition is not without risk. The risks and benefits of parenteral nutrition in the acute setting need to be carefully considered even when it is indicated
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