Development and parametric evaluation of the prototype 2 and 3 flash evaporators

Development of the Prototype 2 and 3 flash evaporator heat sinks which vaporize an expendable fluid to cool a heat transport fluid loop is reported. The units utilize Freon 21 as the heat transport fluid and water as the expendable fluid to meet the projected performance requirements of the space shuttle for both on-orbit and ascent/reentry operations. The evaporant is pulse-sprayed by on-off control onto heat transfer surfaces containing the transport fluid and exhausted to the vacuum environment through fixed area exhaust ducts

Observing workplace incivility towards women: The roles of target reactions, actor motives, and actor-target relationships

The current study conceptualized observer reactions to uncivil behavior towards women as an ethical behavior and examined three factors (target reaction, actor motive, and actor-target relationship) that influence these reactions. Two vignette studies with women and men undergraduate and graduate students in western Switzerland were conducted. Study 1 (N=148) was a written vignette study that assessed how the reaction of female targets to incivility and the motives of actors influenced observer reactions. Results showed that a female target's reaction influenced observers' evaluations of the harm caused by an uncivil incident, and that an actor's motive affected observers' assessments of the necessity to intervene. Study 2 (N=81) was a video vignette study that assessed the effects of the reactions by female targets to incivility and the relationship between the target and the actor on observer reactions.We found that female targets' reactions influenced observers' evaluations of harm and the perceived necessity to intervene. Furthermore, the effect of a female target's reaction on observers' evaluations of harm was moderated by the relationship between the actor and the target: a female target who laughed at the uncivil behavior was perceived as less harmed, when she and the actor had a personal relationship than when they had a professional relationship. When the female target reacted hurt or neutrally, actor-target relationship did not affect observers' evaluations of harm. We conclude by discussing the implications of our findings for theory and practice

Satellite power system: Concept development and evaluation program. Volume 3: Power transmission and reception. Technical summary and assessment

Efforts in the DOE/NASA concept development and evaluation program are discussed for the solar power satellite power transmission and reception system. A technical summary is provided together with a summary of system assessment activities. System options and system definition drivers are described. Major system assessment activities were in support of the reference system definition, solid state system studies, critical technology supporting investigations, and various system and subsystem tradeoffs. These activities are described together with reference system updates and alternative concepts for each of the subsystem areas. Conclusions reached as a result of the numerous analytical and experimental evaluations are presented. Remaining issues for a possible follow-on program are identified

Syntactic View of Sigma-Tau Generation of Permutations

We give a syntactic view of the Sawada-Williams $(\sigma,\tau)$-generation of permutations. The corresponding sequence of $\sigma-\tau$-operations, of length $n!-1$ is shown to be highly compressible: it has $O(n^2\log n)$ bit description. Using this compact description we design fast algorithms for ranking and unranking permutations.Comment: accepted on LATA201

Breeding limits foraging time : evidence of interrupted foraging response from body mass variation in a tropical environment

Funds were received from the Ubbo Emmius grant, Univ. of Groningen and also from the Univ. of St Andrews.Birds should store body reserves if starvation risk is anticipated; this is known as an ‘interrupted foraging response’. If foraging remains unrestricted, however, body mass should remain low to limit the predation risk that gaining and carrying body reserves entails. In temperate environments mass gain in female birds during breeding is often attributed to egg formation and mass loss after incubation to flight adaptation or the effect of reproductive workload, rather than as a result of an adaptive interrupted foraging response to the limited foraging time or unpredictable foraging conditions that breeding demands. In tropical environments, foraging conditions vary more within the breeding season than in temperate environments, and so studies in tropical environments are more suited to decouple the potentially confounded effects of increase in body reserves versus egg formation on the body mass of breeding birds. In this study, we test whether breeding results in an interrupted foraging response in a tropical savannah system using body mass data collected over a 15-year period from female Common Bulbuls Pycnonotus barbatus. This species breeds both in the wet and dry season, despite fewer resources being available in the dry season. Breeding stage predicted female body mass: body mass peaked abruptly during incubation, but was not closely associated with the egg-laying stage, and declined during brood rearing. Breeding females were heavier in the dry season than in the wet season. In the dry season, heavier birds were more likely to incubate eggs or brood chicks. These observations suggest that increased body reserves are required to buffer the consequence of limited foraging time or impoverished foraging conditions, which may be most pronounced during incubation and in the dry season, respectively. Such mass increases are consistent with an interrupted foraging response, which may apply to temperate zone birds experiencing foraging restrictions during breeding.PostprintPeer reviewe

Difficulty of elderly SCI subjects to translate motor recovery -"body function"- into activity of daily living

The objective of this retrospective analysis was to determine whether outcome of body functions and activities as well as length of stay of inpatient rehabilitation is related to age in patients with traumatic spinal cord injury (SCI). Data were collected from a European network of 17 SCI rehabilitation centers (EM-SCI) and 237 traumatic SCI subjects were included. Assessments were performed at one, six and twelve months after SCI. The measures analyzed were: motor score according to the American Spinal Injury Association, Spinal Cord Independence Measure (SCIM), gait speed and length of stay. Correlation analysis was applied to quantify the association between age and change in the outcome measures. A positive relationship was found between age and neurological recovery in both the first and second 6 month- period of assessment. A negative relationship was found between age and change in SCIM in the second six month period after SCI. A negative relationship between age and gait speed was observed in the first half year. Length of stay was not associated with age. It is concluded that age is an important determining factor for functional outcome after SCI and that elderly patients have difficulties in translating an improvement in neurological outcome into functional changes. Therefore, rehabilitation approaches should focus on functional training in elderly subjects

Localized cytokine responses to total knee arthroplasty and total knee revision complications

Background The study of localized immune-related factors has proven beneficial for a variety of conditions, and one area of interest in the field of orthopaedics is the impact of implants and localized infections on immune response. Several cytokines have shown increased systemic concentrations (in serum/plasma) in response to implants and infection, but tissue-level cytokines have not been investigated as thoroughly. Methods This exploratory study investigated tissue-level cytokines in a cohort of patients (N = 17) in response to total knee arthroplasty and total knee revision to better understand the immune response to implants and localized infection (e.g., prosthetic joint infection). The overall goal of this study was to provide insight into the localized cytokine response of tissues and identify tissue-level markers specific to inflammation caused by implants vs. inflammation caused by infection. Tissues were collected across several anatomical locations and assayed with a panel of 20 human inflammatory cytokines to understand spatial differences in cytokine levels. Results In this study, six cytokines were elevated in implanted joints, as compared to native joints: IL-10, IL-12p70, IL-13, IL-17A, IL-4, and TNF-α (p \u3c 0.05). Seven cytokines showed infection-dependent increases in localized tissues: IL-1α, IL-1β, IL-6, IL-8, MCP-1, MIP-1α, and MIP-1β (p \u3c 0.05). Conclusions This study demonstrated that differences exist in tissue-level cytokines in response to presence of implant, and some cytokines were specifically elevated for infection; these responses may be informative of overall tissue health. These results highlight the utility of investigating localized cytokine concentrations to offer novel insights for total knee arthroplasty and total knee revision procedures, as well as their complications. Ultimately, this information could provide additional, quantitative measurements of tissue to aid clinical decision making and patient treatment options

Encircling an Exceptional Point

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP) is encircled. An EP is a parameter setting where the two eigenvalues and the corresponding eigenvectors of the Hamiltonian coalesce. We show that it can be encircled on a path along which the eigenvectors remain approximately real and discuss a microwave cavity experiment, where such an encircling of an EP was realized. Since the wavefunctions remain approximately real, they could be reconstructed from the nodal lines of the recorded spatial intensity distributions of the electric fields inside the resonator. We measured the geometric phases that occur when an EP is encircled four times and thus confirmed that for our system an EP is a branch point of fourth order.Comment: RevTex 4.0, four eps-figures (low resolution

First Experimental Observation of Superscars in a Pseudointegrable Barrier Billiard

With a perturbation body technique intensity distributions of the electric field strength in a flat microwave billiard with a barrier inside up to mode numbers as large as about 700 were measured. A method for the reconstruction of the amplitudes and phases of the electric field strength from those intensity distributions has been developed. Recently predicted superscars have been identified experimentally and - using the well known analogy between the electric field strength and the quantum mechanical wave function in a two-dimensional microwave billiard - their properties determined.Comment: 4 pages, 5 .eps figure

Generalized Killing equations and Taub-NUT spinning space

The generalized Killing equations for the configuration space of spinning particles (spinning space) are analysed. Simple solutions of the homogeneous part of these equations are expressed in terms of Killing-Yano tensors. The general results are applied to the case of the four-dimensional euclidean Taub-NUT manifold.Comment: 10 pages, late