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

Substantial increases in healthcare students’ state empathy scores owing to participation in a single improvisation session

Purpose: To determine whether the 12-item state empathy scale could be modified reliably to measure empathy in healthcare professions students and to detect changes in their empathy owing to a single improvisation (improv) session. Methods: Three cohorts of students from two healthcare professions programs (total = 165 students) participated in an improv session. During the session, one of the researchers (BS) tasked the students with several improv activities. Participants’ self-reported state empathy scores were assessed at three time points (pre-improv, post-improv, and end of semester) using revised, in-class paper versions of the State Empathy Scale. Results: The exploratory factor analysis revealed a single factor solution for the revised scale, justifying the creation of an overall state empathy score from the questionnaire. Cronbach’s alpha reliability values averaged 0.87. Students’ mean empathy scores were higher directly after the improv session than directly prior to the session (p \u3c 0.0001; effect size = r = 0.67, 0.55, and 0.79 for cohorts 1, 2, and 3, respectively). Conclusions: These findings show that a single one- or two-hour improv session can foster substantial increases in healthcare professional students’ state empathy for one another. Greater healthcare professional empathy and compassion foster better healthcare team cooperation and patient outcomes, so healthcare professionals and their students should engage in such empathy-enhancing activities at regular intervals throughout their training and careers

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

Measurements and Analysis of Longitudinal HOM Driven Coupled Bunch Modes in PEP-II Rings

The growth rates of the longitudinal higher-order impedance-driven beam modes have greatly increased since the initial PEP-II design and commissioning. This increase is attributed to the addition of 6 1.2MW RF stations with 8 accelerating cavities in the HER and 2 1.2MW RF stations with 4 accelerating cavities in the LER, which allowed operations at twice the design current and almost four times the luminosity. As a result, the damping requirements for the longitudinal feedback have greatly increased since the design, and the feedback filters and control schemes have evolved during PEP-II operations. In this paper, growth and damping rate data for the higher-order mode (HOM) driven coupled-bunch modes are presented from various PEP-II runs and are compared with historical estimates during commissioning. The effect of noise in the feedback processing channel is also studied. Both the stability and performance limits of the system are analyzed

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