Fabrication of experimental three-meter space telescope primary and secondary mirror support structure

The fabrication of prototype titanium alloy primary and secondary mirror support structures for a proposed experimental three-meter space telescope is discussed. The structure was fabricated entirely of Ti-6Al-4V tubing and plate. Fabrication included the development of procedures including welding, forming, and machining. Most of the structures was fabricated by gas-shielding tungsten-arc (GTA) welding with several major components fabricated by high frequency resistance (HFR) welding

Welding of commercial base plates is investigated

Investigation of aluminum alloy welds reveals that the combinations of metallic elements with hydrogen are not capable of producing weld porosity themselves, rather they tend to increase the amount of porosity only in the presence of arc contamination by water vapor

Flowers and Spiders in Spatial Stimulus-Response Compatibility: Does Affective Valence Influence Selection of Task-Sets or Selection of Responses?

The present study examined the effect of stimulus valence on two levels of selection in the cognitive system, selection of a task-set and selection of a response. In the first experiment, participants performed a spatial compatibility task (pressing left and right keys according to the locations of stimuli) in which stimulus-response mappings were determined by stimulus valence. There was a standard spatial stimulus-response compatibility (SRC) effect for positive stimuli (flowers) and a reversed SRC effect for negative stimuli (spiders), but the same data could be interpreted as showing faster responses when positive and negative stimuli were assigned to compatible and incompatible mappings, respectively, than when the assignment was opposite. Experiment 2 disentangled these interpretations, showing that valence did not influence a spatial SRC effect (Simon effect) when task-set retrieval was unnecessary. Experiments 3 and 4 replaced keypress responses with joystick deflections that afforded approach/avoidance action coding. Stimulus valence modulated the Simon effect (but did not reverse it) when the valence was task-relevant (Experiment 3) as well as when it was task-irrelevant (Experiment 4). Therefore, stimulus valence influences task-set selection and response selection, but the influence on the latter is limited to conditions where responses afford approach/avoidance action coding

Analysis of socio-cultural factors affecting the establishment of a cross-cultural Christian leadership education program in Mexico City

An educational program, or school is a social system defined by norms, values, status and goals (Banks & Banks, 1989). Analyzing socio-cultural factors affecting program development is a preliminary step to assisting in the establishment of a cross-cultural Christian leadership education program in Mexico City. Six categories of socio-cultural factors were derived. They are the following: 1) Community relations issues; 2) Sociological issues; 3) Educational process issues; 4) Attitudinal issues; 5) Administrative issues; and, 6) Mexican governmental and legal issues. Data from interviews and a resulting survey instrument distributed to 53 administrators, professors, students, lay persons and mission directors produced these selected findings and suggestions: Category I: Mexico City's evangelicals favor additional leadership program development. Problems of evangelical acceptance do exist. Category II: Ministry opportunities exist for men and for women. Educating higher SES groups may result in broader ministry opportunities than educating lower SES groups. Leadership education is expressed as the area of greatest ministry need. Category III: The educational program should adapt to Mexican preferred learning styles. Preferred teacher roles are: friendly research guides, not information providers who must discipline a lot. Preferred teaching methods are: student-active, not traditional methods: memorization, dictation and others. Students should acquire attitudinal and cognitive skills. Category IV: North American educators are accepted, but should learn Spanish well. Temperament and cultural differences exist between Mexicans and North Americans. Category V: A dormitory-style program may be beneficial: Mexican students may prefer relational learning styles. Location should be easily accessible by public transportation. Category VI: Mexican law permits, but restricts religious activity. Religious organizations may not own or administrate real estate. Ministers must be Mexican by birth, and forfeit certain civil and political rights

The construction of identities in narratives about serious leisure occupations

Engagement in occupation contributes to the shaping of identity throughout the human life. The act of telling about such engagement involves interaction based on symbolic meaning; the speaker constructing an identity by conveying how the occupation is personally meaningful. This study explored meaning in narratives told by people who engage in serious leisure occupations. A total of 78 narratives were extracted from interviews with 17 people who invest considerable time and other resources into their leisure. Analysis focused on the content, structure and performance of each narrative in order to explore meaning. The meanings were organised into a framework based around three dimensions: the located self, the active self and the changing self. Each dimension has facets that the individual might emphasise, constructing a unique identity. The framework offers a structured basis for conceptualising how occupation contributes to the shaping of the internalised self and the socially situated identity

Challenging Social Cognition Models of Adherence:Cycles of Discourse, Historical Bodies, and Interactional Order

Attempts to model individual beliefs as a means of predicting how people follow clinical advice have dominated adherence research, but with limited success. In this article, we challenge assumptions underlying this individualistic philosophy and propose an alternative formulation of context and its relationship with individual actions related to illness. Borrowing from Scollon and Scollon’s three elements of social action – “historical body,” “interaction order,” and “discourses in place” – we construct an alternative set of research methods and demonstrate their application with an example of a person talking about asthma management. We argue that talk- or illness-related behavior, both viewed as forms of social action, manifest themselves as an intersection of cycles of discourse, shifting as individuals move through these cycles across time and space. We finish by discussing how these dynamics of social action can be studied and how clinicians might use this understanding when negotiating treatment with patients

Migrant care workers at the intersection of rural belonging in small English communities

Shortage of staff in the private care sector brought migrant participants of this study to rural communities in northwest England. The care workers, fourteen highly skilled first-generation migrants, described experiences of feeling unsettled, despite residing in these communities for an average of nine years. Social divisions, such as their race, ethnicity, and gender, intersected in rural England to create an overwhelming, at times, feeling of being othered. We use intersectionality as a framework to examine the advantageous and disadvantageous positionings of migrant workers, alongside their strategies of resistance and adaptation, filling in the gaps that acculturation theory glosses over

The timescale of early land plant evolution

Establishing the timescale of early land plant evolution is essential for testing hypotheses on the coevolution of land plants and Earth's System. The sparseness of early land plant megafossils and stratigraphic controls on their distribution make the fossil record an unreliable guide, leaving only the molecular clock. However, the application of molecular clock methodology is challenged by the current impasse in attempts to resolve the evolutionary relationships among the living bryophytes and tracheophytes. Here, we establish a timescale for early land plant evolution that integrates over topological uncertainty by exploring the impact of competing hypotheses on bryophyte-tracheophyte relationships, among other variables, on divergence time estimation. We codify 37 fossil calibrations for Viridiplantae following best practice. We apply these calibrations in a Bayesian relaxed molecular clock analysis of a phylogenomic dataset encompassing the diversity of Embryophyta and their relatives within Viridiplantae. Topology and dataset sizes have little impact on age estimates, with greater differences among alternative clock models and calibration strategies. For all analyses, a Cambrian origin of Embryophyta is recovered with highest probability. The estimated ages for crown tracheophytes range from Late Ordovician to late Silurian. This timescale implies an early establishment of terrestrial ecosystems by land plants that is in close accord with recent estimates for the origin of terrestrial animal lineages. Biogeochemical models that are constrained by the fossil record of early land plants, or attempt to explain their impact, must consider the implications of a much earlier, middle Cambrian-Early Ordovician, origin