On the design of an adjustable high precision latching hinge

The design and test details of a high precision hinge and locking mechanism created principally in support of the Lockheed space deployable Flexrib Parabolic Antenna concept are presented. These developed improvements in the detail design of ultra-precise rib hinge and contour adjustment mechanisms will allow radio frequency antenna reflectors to expand into the 15-50 meter diameter size class and to support the .013 mm. deployment repeatability tolerance required to support the 12+ GHz frequency range

Developing Teacher Literacy in Appalachian Contexts: Or How I Went South and Learned a New Way of Being in the World

To become literate when we move from one part of the country to another with significant cultural differences, our first task is to learn the new culture so we can more effectively work with our colleagues and our students. When I moved from Bay City, MI, to Morehead, KY, there were many customs I needed to learn. Fortunately, what I learned helped me to cherish both my new colleagues and students

The Monotypic North American Subgenus Larandrena of Andrena (\u3ci\u3eHymenoptera: Apoidea\u3c/i\u3e)

Larandrena contains a single species, A. miserabilis Cresson. This small, common Andrena is found throughout most of the United States and southern Canada in the spring. The subgeneric position, nomenclature, redescription. variation, notes on the biology, parasites, range, seasonal activity and plant host records are included. A. rniserabilis is thought to be an important pollinator of fruit trees

Review of \u3ci\u3eThe Explorers\u27 Texas: The Animals They Found\u3c/i\u3e by Del Weniger

As a mammalogist residing in central Texas, I often try to imagine the great diversity and abundance of mammals present in this state prior to western settlement. There are of course legendary accounts in Texas history and folklore of some of the larger mammals, such as buffalo, bears, and wolves, but I know of no book that systematically recounts the historical distribution, abundance, and behavior of what was once an amazing collection of mammals. Del Weniger\u27s study takes its place as such a unique and well-researched account. This is the second volume of his research, the first covering The Land and Waters. Although subtitled The Animals They Found, the coverage is exclusively mammalian (volumes three and four will cover birds and plants, respectively)

The Evolution of Social and Reproductive Monogamy in Peromyscus, Evidence from \u3cem\u3ePeromyscus californicus\u3c/em\u3e (the California Mouse)

The genus Peromyscus (deer mice) is an attractive group in which to study the evolution of social and mating behaviours. This genus includes over 50 species (Carleton, 1989) that are widely distributed across North and Central America from coast to coast and from the northern subarctic to Panama (Kirkland & Layne, 1989). The diversity in body sizes among Peromyscus ranges from 13 to 77 g (Millar, 1989) and exceeds that of most other genera. Phylogenetic relationships among species of Peromyscus are relatively well understood (Stangl & Baker, 1984), although the systematics of Peromyscus is an active area of study (e.g., Rogers & Engstrom, 1992; Bradley et al., 2000). Most relevant to this chapter, populations and species of Peromyscus exhibit a variety of social behaviours and mating systems (Wolff, 1989), with social monogamy, and particularly reproductive monogamy, being relatively rare. Since monogamy is rare among Peromyscus, those Peromyscus species that exhibit monogamous behaviours may reveal important factors in the evolution of the genus. One of the best studied monogamous species within the genus is P. californicus (California mouse). Association patterns, biparental care, and mating exclusivity indicate that this species is socially and reproductively monogamous, and I will begin by reviewing these elements. Furthermore, recent field experiments demonstrate that male care is critical for offspring survival and is the salient feature of monogamy in this species. I will then review the ecology of female and male home range use and spatial organization and paternal care in other Peromyscus species

Ahead of his time: Joseph Grinnell, natural history, and inclusion and equity in STEM

Joseph Grinnell designed the Natural History of the Vertebrates (NHV) course at the Museum of Vertebrate Zoology, University of California at Berkeley, over 100 years ago and the course has changed little over these years. In this essay, I connect modern pedagogical and cognitive understandings of what we know leads to success among students to the course. This analysis reveals that the course continues to be successful because it has all the elements of a student-centered, active-learning class that leads to better cognitive gains, better retention, and importantly, proportionately better gains for students from underserved populations. This study will be important for advocates of teaching natural history in biology curriculum. Joseph Grinnell diseñó el curso de Historia Natural de los Vertebrados (NHV) en el Museum of Vertebrate Zoology, Universidad de California en Berkeley, hace más de 100 años y el curso ha cambiado poco durante estos años. En este ensayo, conecto la comprensión pedagógica y cognitiva moderna de lo que sabemos que conduce al éxito entre los estudiantes del curso. Este análisis revela que el curso continúa siendo exitoso porque tiene todos los elementos de una clase de aprendizaje activo centrada en el estudiante que conduce a mejores ganancias cognitivas, mejor retención y, lo que es más importante, proporcionalmente mejores ganancias para los estudiantes de poblaciones desatendidas. Este estudio será importante para los defensores de la enseñanza de la historia natural en el plan de estudios de biología