5,417 research outputs found
Characterization of silicon dioxide for a capacitance-type meteoroid penetration detector
Fabrication and testing of large area metal oxide silicon capacitors for micrometeoroid counting in spac
The development of radiation resistant insulating layers for planar silicon technology, 29 May 1968 - 28 June 1969
Ion implantation method for improving radiation resistance of thermal oxides on silico
Approach range and velocity determination using laser sensors and retroreflector targets
Rockwell International is conducting an ongoing program to develop Laser Docking Sensors (LDS) that provide high performance and high intrinsic value while meeting all mission objectives. These LDS systems are now being required to aid future spacecraft docking, station keeping, and berthing/capture systems. Improved automated tracking, rendezvous, soft docking, and capture will be required in the construction and support of SSF and future orbiting platforms. The development of a practical LDS requires an easy-to-operate, low-cost, compact system. A wide range of options for laser range detection equipment, ranging from commercial technology to specialized military systems, was evaluated. This evaluation focused on both direct applicability of existing systems and usability of specific technologies contained in these systems. From these efforts it was determined that a new approach provided the greatest promise of fulfilling all mission requirements at the lowest life-cycle cost
Particulate and aerosol detector
A device is described for counting aerosols and sorting them according to either size, mass or energy. The component parts are an accelerator, a capacitor sensor and a readout. The accelerator is a means for accelerating the aerosols toward the face of the capacitor sensor with such force that they partially penetrate the capacitor sensor, momentarily discharging it. The readout device is a means for counting the number of discharges of the capacitor sensor and measuring the amplitudes of these different discharges. The aerosols are accelerated by the accelerator in the direction of the metal layer with such force that they penetrate the metal and damage the oxide layers, thereby allowing the electrical charge on the capacitor to discharge through the damaged region. Each incident aerosol initiates a discharge path through the capacitor in such a fashion as to vaporize the conducting path. Once the discharge action is complete, the low resistance path no longer exists between the two capacitor plates and the capacitor is again able to accept a charge. The active area of the capacitor is reduced in size by the damaged area each time a discharge occurs
Daily Sleep Quality is Associated with Daily Cognition in Late-Life
Background: Older adults often face sleep disturbance or cognitive decline that goes beyond the scope of normal aging. The present study examined the relationship between self-reported sleep quality and self-reported daytime attention in a community-dwelling sample of older men at the between-persons and within-persons levels of association.
Methods: Thirty-eight participants (M age =75.36 years, SD age =7.51 years, range=66-90 years) completed a twice-daily sleep diary for one week. Sleep quality and attention were assessed using a single-item 0-10 rating scales from the morning diary (“How was the quality of your sleep last night?”) and from the evening diary (“How was your attention today?”). A two-level multilevel model was parameterized with days nested within individuals to examine whether nightly sleep quality predicts an individual’s daily attention rating.
Results: A multilevel model predicting self-reported attention revealed (1) older individuals who reported better sleep quality reported having better daily attention [Beta=0.64, t(248.15)=10.12, p\u3c0.001] and (2) following a day of above-average sleep quality, older individuals experienced above-average attention [Beta=0.16, t(259.79)=2.75, p=.006].
Conclusion: Not only was overall sleep quality associated with self-reported attention, but a good night\u27s sleep was associated with better self-reported next-day attention. Results point to the potential importance of fluctuations in sleep quality for daytime functioning. Interventions aimed at improving nightly sleep consistency may be worth exploring as methods to improve daytime cognitive functioning in older adults.
Support: This work was supported by the Sleep Research Society Foundation/Jazz Pharmaceuticals (001JP13, PI: Dzierzewski) and by the National Institute on Aging of the National Institutes of Health under Award Number K23AG049955 (PI: Dzierzewski), and National Heart Lung and Blood Institute at the National Institutes of Health under award number K24HL143055 (PI: Martin). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the Department of Veterans Affairs.https://scholarscompass.vcu.edu/gradposters/1089/thumbnail.jp
Non-invasive Measures of Core Temperature versus Ingestible Thermistor during Exercise in the Heat
International Journal of Exercise Science 10(2): 225-233, 2017 The accuracy of core temperature (Tc) thermometry from temporal, tympanic, and oral thermometry devices has been variable during exercise in a hot, humid environment. The purpose of the present study was to cross-validate temporal, two tympanic devices, and oral devices compared to an ingestible thermistor during exercise in a hot, humid environment. Fourteen young, active adults (6 women) completed a graded exercise test until voluntary exhaustion in an environmental chamber (35.5 ± 0.6 °C, 53.9 ± 5.8 % RH). There was no statistical difference in mean temperature between tympanic device 1 and pill-based core temperature (PBTc) measurements across all time points and were positively correlated (0.357; P\u3c0.001). Temperatures of tympanic device 2 were statistically higher than PBTc (37.8 ± 0.7 ºC vs. 37.6 ± 1.0 ºC; respectfully) (P=0.008). At all time points, temperatures for the second tympanic device and PBTc were positively correlated (0.192; P=0.043). Temporal and PBTc values did not differ across time points and were positively correlated (0.262; P=0.005) across all time points. Mean oral temperature was significantly less than mean PBTc across all time points. (37.0 ± 0.4 ºC vs. 37.6 ± 1.0 ºC, respectively) (P\u3c0.001). Across all time points, oral and PBTc were positively correlated (0.262; P=0.010). Tympanic and temporal devices can reflect Tc while exercising in a hot, humid environment. However, care should be taken when selecting the tympanic or temporal measurement device and validation is advised prior to heat illness mitigation in the field
The Environmental Effects of Uranium Exploration and Mining
Uranium exploration and mining is increasing as the Nation\u27s demand for energy grows. The environmental impacts associated with this exploration and mining are not severe and compare favorably with impacts from the production of other energy resources
The influence of space radiation upon the MOS micrometeoroid capacitor detector Final report, 17 Jul. 1970 - 16 Feb. 1971
Possible electron irradiated failure modes of MOS micrometeoroid capacitor detector
Ichnology of the Palaeogene Richmond Formation of eastern Jamaica - the final chapter?
Previously unrecorded ichnotaxa from the Palaeogene Richmond Formation of eastern Jamaica, namely Cos-morhaphe cf. gracilis, Helminthoida crassa, Paleodictyon? isp. and Taenidium cameronensis, are described. The ichnotaxa are assigned to a previously defined deep-water Scolicia ichnocoenosis characteristic of turbidilic strata. The general exclusion of graphoglyptids in these strata is believed to reflect a combination of the relatively shallow-water depths in which the turbidilic strata accumulated, the abundant organic matter available for biological consumption, and the existence of fluctuating dysaerobic/anoxic and oxygenated conditions at, or immediately below, the sediment-water interface.
RÉSUMÉ
Les ichnofossiles auparavant non enregistrés provenant de la Formation paleogène de Richmond de Test de la Jamaique, soil Cosmorhaphe cf. gracilis, Helminthoida crassa, Paleodictyon? isp. et Taenidium cameronensis, sont décrits. Ces ichnofossiles sont assigned à l’assemblage d'eau profonde Scolicia anterieurement défini, caractérislique des strates de turbidites. L'absence générate de graphoglyplides dans ces couches est considérée comme refletant une combinaison de la faible profondeur relative à laquelle les strates de turbidites se sont accumulées, l'abondance de matière organique disponible pour la consommation biologique et l’existence de conditions anoxiques et oxygénées fluctuantes è l'interface eau-sédiment ou immédiatement en-dessous.
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