Preliminary design study of a regenerative life support system information management and display system

The instrumentation requirements for a regenerative life support systems were studied to provide the earliest possible indication of a malfunction that will permit degradation of the environment. Four categories of parameters were investigated: environmental parameters that directly and immediately influence the health and safety of the cabin crew; subsystems' inputs to the cabin that directly maintain the cabin environmental parameters; indications for maintenance or repair; and parameters useful as diagnostic indicators. A data averager concept is introduced which provides a moving average of parameter values that is not influenced by spurious changes, and is convenient for detecting parameter rates of change. A system is included to provide alarms at preselected parameter levels

Altitude characteristics of selected air quality analyzers

The effects of altitude (pressure) on the operation and sensitivity of various air quality analyzers frequently flown on aircraft were analyzed. Two ozone analyzers were studied at altitudes from 600 to 7500 m and a nitrogen oxides chemiluminescence detector and a sulfur dioxide flame photometric detector were studied at altitudes from 600 to 3000 m. Calibration curves for altitude corrections to the sensitivity of the instruments are presented along with discussion of observed instrument behavior

Stimulus-dependent effects on tactile spatial acuity

BACKGROUND: Previous studies have shown that spatio-tactile acuity is influenced by the clarity of the cortical response in primary somatosensory cortex (SI). Stimulus characteristics such as frequency, amplitude, and location of tactile stimuli presented to the skin have been shown to have a significant effect on the response in SI. The present study observes the effect of changing stimulus parameters of 25 Hz sinusoidal vertical skin displacement stimulation ("flutter") on a human subject's ability to discriminate between two adjacent or near-adjacent skin sites. Based on results obtained from recent neurophysiological studies of the SI response to different conditions of vibrotactile stimulation, we predicted that the addition of 200 Hz vibration to the same site that a two-point flutter stimulus was delivered on the skin would improve a subject's spatio-tactile acuity over that measured with flutter alone. Additionally, similar neurophysiological studies predict that the presence of either a 25 Hz flutter or 200 Hz vibration stimulus on the unattended hand (on the opposite side of the body from the site of two-point limen testing – the condition of bilateral stimulation – which has been shown to evoke less SI cortical activity than the contralateral-only stimulus condition) would decrease a subject's ability to discriminate between two points on the skin. RESULTS: A Bekesy tracking method was employed to track a subject's ability to discriminate between two-point stimuli delivered to the skin. The distance between the two points of stimulation was varied on a trial-by-trial basis, and several different stimulus conditions were examined: (1) The "control" condition, in which 25 Hz flutter stimuli were delivered simultaneously to the two points on the skin of the attended hand, (2) the "complex" condition, in which a combination of 25 Hz flutter and 200 Hz vibration stimuli were delivered to the two points on the attended hand, and (3) a "bilateral" condition, in which 25 Hz flutter was delivered to the two points on the attended hand and a second stimulus (either flutter or vibration) was delivered to the unattended hand. The two-point limen was reduced (i.e., spatial acuity was improved) under the complex stimulus condition when compared to the control stimulus condition. Specifically, whereas adding vibration to the unilateral two-point flutter stimulus improved spatial acuity by 20 to 25%, the two-point limen was not significantly affected by substantial changes in stimulus amplitude (between 100 – 200 μm). In contrast, simultaneous stimulation of the unattended hand (contralateral to the attended site), impaired spatial acuity by 20% with flutter stimulation and by 30% with vibration stimulation. CONCLUSION: It was found that the addition of 200 Hz vibration to a two-point 25 Hz flutter stimulus significantly improved a subject's ability to discriminate between two points on the skin. Since previous studies showed that 200 Hz vibration preferentially evokes activity in cortical area SII and reduces or inhibits the spatial extent of activity in SI in the same hemisphere, the findings in this paper raise the possibility that although SI activity plays a major role in two-point discrimination on the skin, influences relayed to SI from SII in the same hemisphere may contribute importantly to SI's ability to differentially respond to stimuli applied to closely spaced skin points on the same side of the body midline

USING BILINGUAL BOOKS TO ENHANCE LITERACY AROUND THE WORLD

This paper focuses on approaches and practices for developing biliteracy and bilingualism across diverse international settings. The authors present a framework for why bilingual books can be used to develop both native language and second or other languages through reading and writing activities. Bilingual books and a basic taxonomy of types of bilingual books are described. A rationale for their use is provided in that bilingual books provide linguistic resources such as vocabulary development for students to develop across two languages (Ernst-Slavit&Mulhern, 2003) while also fostering awareness of cultural and social awareness (e.g, Botelho& Rudman, 2009). The authors provide specific examples of both linguistic and cultural support. Specific activities that promote bilingualism and biculturalism as an aim include read-aloud, shared reading, and writing instruction which can incorporate the use of student-created books in both languages. These student-written bilingual texts can draw on local cultural and linguistic practices in their composition (e.g., Dworin, 2006). Finally, the authors conclude with ways that cross-age reading and family involvement can support bilingual development by using bilingual books

Towards Establishing Age-Related Cortical Plasticity on the Basis of Somatosensation.

Age-related somatosensory processing appears to remain intact where tasks engage centrally- as opposed to peripherally-mediated mechanisms. This distinction suggests that insight into alterations in neural plasticity could be derived via metrics of vibrotactile performance. Such an approach could be used to support the early detection of global changes in brain health but current evidence is limited. Knowledge of the precise conditions in which older adults are expected to sustain somatosensory performance is largely unknown. For this purpose, the study aimed to characterize age-related performance on tactile detection and discrimination-based tests. Accordingly, a group of young and older adult participants took part in simple reaction time and amplitude discrimination tasks. Participants' ability to distinguish between stimuli on the basis of amplitude was assessed with and without dual-site adaptation, which has been proposed to refine cortical responses and improve behavioral performance. The results show that while older adults exhibited significantly prolonged (p < .001, d = 1.116) and more variable (p = .022, d = 0.578) information processing speed compared to young adults, they were able to achieve similar scores in baseline discrimination (p = .179, d = 0.336). We also report, for the first time, that older adults displayed similar performance improvements to young adults, under conditions of dual-site adaptation (p = .948, d = 0.016). The findings support the argument that centrally-mediated mechanisms remain intact in the ageing population. Accordingly, dual-site adaptation data provide compelling new evidence of somatosensation in ageing that will contribute towards the development of an assessment tool to ascertain pre-clinical, age-related changes in the status of cortical function

In situ sensors for measurements in the global trosposphere

Current techniques available for the in situ measurement of ambient trace gas species, particulate composition, and particulate size distribution are reviewed. The operational specifications of the various techniques are described. Most of the techniques described are those that have been used in airborne applications or show promise of being adaptable to airborne applications. Some of the instruments described are specialty items that are not commercially-available. In situ measurement techniques for several meteorological parameters important in the study of the distribution and transport of ambient air pollutants are discussed. Some remote measurement techniques for meteorological parameters are also discussed. State-of-the-art measurement capabilities are compared with a list of capabilities and specifications desired by NASA for ambient measurements in the global troposphere

The 1979 Southeastern Virginia Urban Plume Study (SEV-UPS): Surface and airborne studies

The operation of two surface monitoring stations (one in downtown Norfolk, Virginia, one south of the city near the Great Dismal Swamp) and the collection of 40 hours of airborne measurements is described. Surface site measurements of ozone, oxides of nitrogen, sulfur dioxide, temperature, dew point, b sub seat, and condensation nuclei were made. Instrument calibrations, quality assurance audits, and preliminary data analysis in support of the Urban Plume Study were also made. The air pollution problems that were addressed are discussed. Data handling procedures followed for the surface stations are presented. The operation of the aircraft sampling platform is described. Aircraft sampling procedures are discussed. A preliminary descriptive analysis of the aircraft data is given along with data or plots for surface sites, airborne studies, hydrocarbon species, and instrument performance audits. Several of the aircraft flights clearly show the presence of an urban ozone plume downwind of Norfolk in the direction of the mean wind flow