168 research outputs found
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Some Perspectives on the Banking Environment: 1988-1992
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The Texas Economy: Financing Availability
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Five Strategies for Teaching Vocabulary As a Process
Building vocabulary is an important component of any reading program; it is a crucial comprehension skill. In fact, Davis (1968), in an analysis of comprehension skills, found word knowledge to be the key factor in comprehension. However, vocabulary has often been relegated to a secondary position in the scheme of language development, and no real systematic program for vocabulary building in reading or language arts course really exists (0\u27 Rourke, 1974). Additionally, the approaches to vocabulary study have long emphasized product over process (Brooks, 1986). Students have been presented with long lists of often unrelated terms that they could study and memorize for a test only to purposefully forget them following the quiz. Yet, readers need to expand their vocabulary range, and speakers require an ever increasing number of specific terms to communicate fully and effectively at various levels. How then does the teacher incorporate vocabulary study into the classroom? A few process oriented strategies seem to be the answer for meaningful vocabulary development and retention. In this paper, five strategies for vocabulary as a process are provided
Optical properties monitor: Experiment definition phase
The stability of materials used in the space environment will continue to be a limiting technology for space missions. The Optical Properties Monitor (OPM) Experiment provides a comprehensive space research program to study the effects of the space environment-both natural and induced-on optical, thermal and space power materials. The OPM Experiment was selected for definition under the NASA/OAST In-Space Technology Experiment Program. The results of the OPM Definition Phase are presented. The OPM Experiment will expose selected materials to the space environment and measure the effects with in-space optical measurements. In-space measurements include total hemispherical reflectance total integrated scatter and VUV reflectance/transmittance. The in-space measurements will be augmented with extensive pre- and post-flight sample measurements to determine other optical, mechanical, electrical, chemical or surface effects of space exposure. Environmental monitors will provide the amount and time history of the sample exposure to solar irradiation, atomic oxygen and molecular contamination
Alignment Test Results of the JWST Pathfinder Telescope Mirrors in the Cryogenic Environment
After integration of the Optical Telescope Element (OTE) to the Integrated Science Instrument Module (ISIM) to become the OTIS, the James Webb Space Telescope OTIS is tested at NASAs Johnson Space Center (JSC) in the cryogenic vacuum Chamber A for alignment and optical performance. The alignment of the mirrors comprises a sequence of steps as follows: The mirrors are coarsely aligned using photogrammetry cameras with reflective targets attached to the sides of the mirrors. Then a multi-wavelength interferometer is aligned to the 18-segment primary mirror using cameras at the center of curvature to align reflected light from the segments and using fiducials at the edge of the primary mirror. Once the interferometer is aligned, the 18 primary mirror segments are then adjusted to optimize wavefront error of the aggregate mirror. This process phases the piston and tilt positions of all the mirror segments. An optical fiber placed at the Cassegrain focus of the telescope then emits light towards the secondary mirror to create a collimated beam emitting from the primary mirror. Portions of the collimated beam are retro-reflected from flat mirrors at the top of the chamber to pass through the telescope to the SI detector. The image on the detector is used for fine alignment of the secondary mirror and a check of the primary mirror alignment using many of the same analysis techniques used in the on-orbit alignment. The entire process was practiced and evaluated in 2015 at cryogenic temperature with the Pathfinder telescope
Experience of unpleasant sensations in the mouth after injection of saline from prefilled syringes
Background
Nurses at The Norwegian Radium Hospital have reported that some patients notice an unpleasant smell or taste in accordance with flushing of intravenous lines with commercially available prefilled syringes. We have conducted a study in healthy volunteers to investigate the occurrence, consistency and intensity of this phenomenon.
Methods
A randomised, blinded, crossover study comparing commercial available prefilled saline 9 mg/ml syringes to saline 9 mg/ml for injection in polyethylene package was performed in 10 healthy volunteers. The volunteers were given intravenous injections of varying volume and speed. Data were analysed using descriptive statistics, and also Wilcoxon Signed Rank Test to compare groups.
Results
After intravenous injection, 2 of 15 recordings demonstrated any sensation of smell or taste after injection of saline from polyethylene package, while 14 of 15 recordings noted a sensation after injection of saline from prefilled syringes. The intensity of the unpleasant sensation was rated significantly higher after injection of saline from prefilled syringes compared to saline from polyethylene (p = 0.001).
Conclusions
Injection of saline from prefilled syringes in healthy volunteers resulted in an experience of bad taste or smell. It is important that nurses and health workers are aware of the phenomenon as described in this article in order to choose the preferred product for a given patient
Performance of the Center-Of-Curvature Optical Assembly During Cryogenic Testing of the James Webb Space Telescope
The James Webb Space Telescope (JWST) primary mirror (PM) is 6.6 meters in diameter and consists of 18 hexagonal segments, each 1.5 meters point-to-point. Each segment has a 6 degree-of-freedom hexapod actuation system and a radius-of-curvature (ROC) actuation system. The full telescope was tested at its cryogenic operating temperature at Johnson Space Center (JSC) in 2017. This testing included center-of-curvature measurements of the PM wavefront error using the Center-of-Curvature Optical Assembly (COCOA), along with the Absolute Distance Meter Assembly (ADMA). The COCOA included an interferometer, a reflective null, an interferometer-null calibration system, coarse and fine alignment systems, and two displacement measuring interferometer systems. A multiple-wavelength interferometer was used to enable alignment and phasing of the PM segments. By combining measurements at two laser wavelengths, synthetic wavelengths up to 15 millimeters could be achieved, allowing mirror segments with millimeter-level piston errors to be phased to the nanometer level. The ADMA was used to measure and set the spacing between the PM and the focus of the COCOA null (i.e., the PM center-of-curvature) for determination of the ROC. This paper describes the COCOA, the PM test setup, the testing performed, the test results, and the performance of the COCOA in aligning & phasing the PM segments and measuring the final PM wavefront error
Strategies to prevent central line-associated bloodstream infections in acute-care hospitals: 2022 Update.
Strategies to prevent central line-associated bloodstream infections in acute-care hospitals: 2022 Update
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