A System for In-Flight Determination of Lunar Orbit Injection Conditions

This paper is based on vork accomplished by the Douglas Missile and Space Systems Division under Contracts NAS7-380 and NAST-53T for the Goddard Space Flight Center, National Aeronautics and Space Administration, Greenbelt, Maryland

Impact and Casualty Prediction for Malfunctioning Multi-Stage Vehicles

Presented is a rather general explanation of an automated method for determining, by Monte Carlo techniques, the probabilities of impacting populated land masses and causing a casualty when a malfunctioning multi-stage vehicle deviates from its normal instantaneous earth impact pattern. The generation of this data is explained through the use of illustrative material which describes the necessary flow of information and computational operations. The economic advantages of the method discussed are compared, in terms of manpower, computer time, and total elapsed time requirements,with those of a forerunning method used to generate such data

Lessons Learned from Positon-Electron Project Low Level RF and Longitudinal Feedback

The PEP-II B-Factory collider ended the final phase of operation at nearly twice the design current and 4X the design luminosity. To highlight the evolution from the original conceptual design through to the 1.2E34 final machine we choose one example each from the broadband feedback and from the LLRF system. They illustrate the original design estimation missed some very significant details, and how in the course of PEP-II operation unexpected difficulties led to significant insights and new approaches which allowed higher machine performance. We present valuable ”lessons learned” which are of interest to designers of next generation feedback and impedance controlled LLRF systems

Is residents’ satisfaction with life a precursor to experiencing emotional solidarity with tourists?

In an effort to explore additional variables as antecedents of emotional solidarity, satisfaction with life (SWL) was considered in this study. More specifically, the research question posed in this paper is, can Deiner et al.’s (1985) Satisfaction with Life Scale (SWLS) significantly predict the three factors of the Emotional Solidarity Scale (ESS): welcoming nature, emotional closeness, and sympathetic understanding? Reliabilities were strong for all four measures. SWLS significantly predicted all three emotional solidarity factors, albeit only explaining a modest degree of variance in each of the dependent variables. Practical implications are discussed

Short versus long silver nanowires: a comparison of in vivo pulmonary effects post instillation.

BackgroundSilver nanowires (Ag NWs) are increasingly being used to produce touchscreens for smart phones and computers. When applied in a thin film over a plastic substrate, Ag NWs create a transparent, highly-conductive network of fibers enabling the touch interface between consumers and their electronics. Large-scale application methods utilize techniques whereby Ag NW suspensions are deposited onto substrates via droplets. Aerosolized droplets increase risk of occupational Ag NW exposure. Currently, there are few published studies on Ag NW exposure-related health effects. Concerns have risen about the potential for greater toxicity from exposure to high-aspect ratio nanomaterials compared to their non-fibrous counterparts. This study examines whether Ag NWs of varying lengths affect biological responses and silver distribution within the lungs at different time-points.MethodsTwo different sizes of Ag NWs (2 μm [S-Ag NWs] and 20 μm [L-Ag NWs]) were tested. Male, Sprague-Dawley rats were intratracheally instilled with Ag NWs (0, 0.1, 0.5, or 1.0 mg/kg). Broncho-alveolar lavage fluid (BALF) and lung tissues were obtained at 1, 7, and 21 days post exposure for analysis of BAL total cells, cell differentials, and total protein as well as tissue pathology and silver distribution.Results and conclusionsThe two highest doses produced significant increases in BAL endpoints. At Day 1, Ag NWs increased total cells, inflammatory polymorphonuclear cells (PMNs), and total protein. PMNs persisted for both Ag NW types at Day 7, though not significantly so, and by Day 21, PMNs appeared in line with sham control values. Striking histopathological features associated with Ag NWs included 1) a strong influx of eosinophils at Days 1 and 7; and 2) formation of Langhans and foreign body giant cells at Days 7 and 21. Epithelial sloughing in the terminal bronchioles (TB) and cellular exudate in alveolar regions were also common. By Day 21, Ag NWs were primarily enclosed in granulomas or surrounded by numerous macrophages in the TB-alveolar duct junction. These findings suggest short and long Ag NWs produce pulmonary toxicity; thus, further research into exposure-related health effects and possible exposure scenarios are necessary to ensure human safety as Ag NW demand increases

Modeling and Simulation of Longitudinal Dynamics for LER-HER PEP II Rings

A time domain modeling and simulation tool for beam-cavity interactions in LER and HER rings at PEP II are presented. The motivation for this tool is to explore the stability margins and performance limits of PEP II RF systems at higher currents and upgraded RF configurations. It also serves as test bed for new control algorithms and can define the ultimate limits of the architecture. The time domain program captures the dynamical behavior of the beam-cavity interaction based on a reduced model. The ring current is represented by macro-bunches. Multiple RF station in the ring are represented via one or two macro-cavities. Each macro-cavity captures the overall behavior of all the 2 or 4 cavity RF station. Station models include nonlinear elements in the klystron and signal processing. This allows modeling the principal longitudinal impedance control loops interacting with the longitudinal beam model. Validation of simulation tool is in progress by comparing the measured growth rates for both LER and HER rings with simulation results. The simulated behavior of both machines at high currents are presented comparing different control strategies and the effect of non-linear klystrons in the growth rates

Blindness Due to Polymicrogyria and Asymmetrical Dilation of the Lateral Ventricles in Standard Poodles

Polymicrogyria and asymmetric dilation of the lateral ventricles were seen in related Standard poodles that had cortical blindness. Three of the affected dogs also had gait and postural abnormalities, and one of these had seizures.Two of the affected dogs were littermates. Thorough ophthalmologic and neurologic examinations (including electroretinography, electromyography, cerebrospinal fluid analysis, plain radiographs, and computerized tomography scans) revealed no significant abnormalities outside of the brain that would account for the blindness. Computerized tomography scans in three dogs demonstrated bilateral dilation of the lateral ventricles which was more severe in the right. All dogs were necropsied between 5 and 9 months of age and had strikingly similar brain abnormalities. Numerous small irregular gyri with shallow sulci covered the middle and caudal dorsal and lateral cerebral cortex. The bony ridges of the inner calvaria in this area conformed to the underlying microgyral pattern. The lateral ventricles were asymmetrically dilated with the right more severely affected, particularly in the occipital area, and the cortical grey and white matter, including the corpus callosum, were thinned in these areas. The third and fourth ventricles and mesencephalic aqueduct were normal. Histologically, there was thinning and simplification of the cortical grey matter with an increased density of medium to large neurons. The corona radiata and subcortical white matter were also thinner than normal with no evidence of demyelination of astrocytic scarring. This congenital anomaly of the visual cortex causing blindness in the Standard Poodle appears to be inherited as an autosomal recessive trait

Survey of attitudes toward performing and reflecting on required team service-learning (SASL): psychometric data and reliability/validity for healthcare professions students in preclinical courses

PurposePreviously we assessed healthcare professional students’ feelings about team-based learning, implicit bias, and service to the community using an in-house paper survey. In this study, we determined whether this survey is a reliable and valid measure of prospective medical students’ attitudes toward required service-learning in an Immunology course. To our knowledge, no published questionnaire has been shown to be dependable and useful for measuring such attitudes using only eight survey items.MethodsFifty-eight prospective medical students in Colorado (CO) and 15 in Utah (UT) completed the same Immunology course using remote technology. In addition to the usual course content, students were required to write critical reflections on required team service-learning. On the last day of class, they completed the survey of attitudes toward service-learning (SASL).ResultsData analyses found Cronbach’s alpha values of 0.84 and 0.85 for the surveys of UT and CO students, respectively. Factor analysis of CO student data revealed only one Eigenvalue greater than one (3.95) justifying retention of a single factor termed “attitudes toward required service-learning.” In addition, CO students’ attitudes toward community service were highly positive, while UT students’ attitudes were nearer neutral (p < 0.0001).ConclusionOur factor analysis and good Cronbach’s alpha values support the conclusion that the SASL was a reliable measure of prospective medical students’ attitudes toward required team service-learning for an Immunology course. Moreover, we used the SASL to distinguish these attitudes in CO versus UT students, and, thus, the SASL appears to be a valid measure of this difference. Calculation of similarly good Cronbach’s alpha values – for a predecessor of the SASL among pharmacy, masters, and medical students at another institution – indicates that the SASL may be useful more widely. However, the reliability and validity of the SASL needs to be demonstrated more rigorously for other healthcare students at different universities