117,463 research outputs found
Personal Papers (MS 80-0002)
No full textLetter from Harris L. Kempner to Katie Fosdick briefly discussing how well the cocktail party went
Single phase energy minimizers for materials with nonlocal spatial dependence
No full textFosdick, Roger L.; Mason, Darren E.. (1994). Single phase energy minimizers for materials with nonlocal spatial dependence. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/2568
Reformation Instability in Elastic Solids
No full textThe reformation of a body fundamentally involves the mapping of one natural reference configuration of it into another natural reference configuration. The mass and the constitutive properties of the material remain unaltered, but the overall shape of the reference configuration generally changes. If, when a natural reference configuration is distorted, there is a portion of the boundary of the body that is displacement controlled, then a reformation of the body must be such that the original displacement controlled part of the boundary and its reformation are identical. In common applications that involve reformation, the remainder of the boundary is traction-free and a reformation essentially involves a change of the morphology of this traction-free surface. For example, undulations are often a characteristic feature of the reformation of a free, plane boundary surface. Reformations are a result of a material instability and they may associate with a chemically induced diffusive processes in which particles of the body move into preferred places. Fundamentally, a reformation is generated in response to the drive to lower the total stored energy of the body. In this work we are not concerned with the physical processes that take place during reformation, but rather we are concerned with characterizing the onset of the instability. We develop a variational characterization of the reformation instability for a nonlinear elastic body and we include the effect of surface energy. As an example, we consider the axial deformation of a circular cylinder and argue that small scale nano-wires, for which the diameter-to-length ratio is sufficiently small, are expected to be stable with respect to spatial variations when extended. Moreover, we observe that if the surfacial energy function is sufficiently convex at the undistorted state such wires may also be stable with respect to spatial variations when compressed. We then show that such small scale nano-wires are unstable with respect to reformation when either extended or compressed. © 2011 Springer Science+Business Media B.V
An analysis of the effect of contrasting theologies of preaching on the teaching of preaching in British institutions of higher learning
No full textThis study examines the efforts of British universities
and colleges to educate students for the ministry of
preaching. It evaluates the hypothesis that a preaching
lecturer's theology significantly influences his teaching,
both in its content and methodology.
A summary and comparison of seven twentieth century
theologies of preaching serves as the foundation for this
study. The research considered each theology as presented
by either its originator or a leading exponent: Harry
Emerson Fosdick, Rudolf Bultmann, Karl Barth, Paul Tillich,
D. Martyn Lloyd-Jones, James Stewart, and Karl Rahner.
Surveys completed by fifty-five lecturers in preaching
provided the second primary focus of research. These
surveys both described current practices in homiletical
education and offered a means of dividina the lecturers into
subgroups for purposes of comparing their teaching. In
order to evaluate the primary hypothesis that theology
exerts great influence on the teaching of preaching, the
study compares the teaching practices of theological
subgroupings of lecturers (each grouping matched with one of
the theologians mentioned above). Likewise, it compares the
teaching of other lecturer subaroupings formed on the basis
of contrasting institutional and denominational settings.
Institutional and denominational setting does affect
the teaching of preaching, but, as hypothesized, not to the
degree theology does. The manner in which a lecturer's
theology determines his teaching is most noticeable in
relation to three questions relating to teaching content:
(1) From what source(s) should preachers seek preaching
content? (2) On what basis should preachers select content
from their source(s)? (3) Once the content has been
determined, by what criteria should preachers prepare
material for delivery?
A comparison of contemporary preaching theologies (and
the resultant contrasts in homiletical education) bespeak
the rich breadth within the Western Christian tradition
Co-receptor (CD4/CD8) engagement enhances CD3-induced apoptosis in thymocytes. Implications for negative selection.
No full textCo-receptor (CD4/CD8) engagement enhances CD3-induced apoptosis in thymocytes. Implications for negative selection.
No full textMelt transport and magma accumulation in a migmatite-cored gneiss dome, Fosdick Mountains, West Antarctica.
No full textUniversity of Minnesota Ph.D. dissertation. July 2009. Major: Geology. Advisors: Christian Teyssier, Donna L. Whitney. 1 computer file (PDF); x, 233 pages, Ill maps (some col.)Expansive cliff-face exposures in the Fosdick Mountains (Antarctica) migmatite-cored gneiss dome enabled the documentation of suprasolidus deformation and melt migration structures in middle to lower crustal rocks at a scale significant for continental differentiation and crustal flow. Using field relations, U-Pb geochronology, and argon thermochronology, work in the Fosdick dome has examined the role of oblique deformation in the flow of partially molten crust, the internal segregation and emplacement of granite, and the relation between oblique detachment systems and exhumation of migmatite terrains.
The Fosdick dome developed in the mid-Cretaceous during oblique plate convergence along the East Gondwana margin of Marie Byrd Land-New Zealand. Structures and fabrics in the dome record the middle to lower crustal response to intracontinental crustal extension and a transition from wrench to transtension associated with development of the West Antarctic Rift System. In the mid-Cretaceous, the dome was constructed and exhumed within a dilation zone that developed along an inferred, crustal-scale, dextral strike-slip fault owing to contrasting competency of granodiorite and metasedimentary gneiss. The pressure gradients created by the opening of the dilation zone induced melt migration into the low-pressure region, forming migmatites and leucogranite sheets. The opening of the dilation zone, influx of melt, and the accumulation of leucogranite sheets initiated movement on the dextral normal oblique South Fosdick Detachment zone, which led to cooling and exhumation of the dome.
Mid-crustal migmatites and granites comprise the Fosdick dome. Residual metatexitic paragneiss, metatexitic orthogneiss units, and diatexite migmatites form an ~5 km thick section that partially preserves the lithologic heterogeneities developed in the Paleozoic. An ~2 km thick subhorizontal leucogranite sheeted complex was emplaced above the migmatites. The leucogranite sheets grade into, and syntectonically intrude, a km thick metatexitic migmatite unit that preserves solid-state fabrics related to the South Fosdick Detachment zone. Interconnected leucosome and leucogranite networks are the remnant pathways of a polyphase permeability network that allowed the transport of melt through, and the accumulation of magma in, the crustal layer of the Fosdick dome.
In the Fosdick dome, lineations and fold axes record a stretching axis oriented 235 ± 5. Steep foliation domains that host granite and leucosome strike NE-SW. These foliations are crosscut and folded by subhorizontal foliation domains that strike ENE-WSW and also host granite and leucosome. The stretching axis of 055-235 is oblique to the strike of the bounding strike-slip fault, oriented 100-280, and the long axis of the dome, oriented 080-260. Solid-state structures in the detachment zone that trend NE-SW and record top-to-the-SW motion are overprinted by brittle structures that record N-S stretching, consistent with N-S stretching brittle structures in the hanging wall rocks. These fabrics and structures record a transition from wrench deformation to extension-dominated transtension within the Fosdick dome related to oblique plate convergence along the East Gondwana margin and development of the West Antarctic Rift System.
U-Pb SHRIMP zircon ages of leucosome and granite indicate a 15 myr period of suprasolidus deformation between ca. 117-102 Ma. Steep foliation domains host an older group of leucosome and granite with ages between ca. 117-115 Ma, whereas subhorizontal foliation domains and the detachment zone host younger leucosome and granite with ages between ca. 109-102 Ma. These ages suggest the transition from wrench to extension-dominated transtension and detachment development occurred within 6 myr. Steep domains preserve steep former melt pathways that are relatively minor in abundance, and this may indicate melt transport through the crustal level of the Fosdick dome during wrench. Subhorizontal domains host thick and laterally extensive leucogranitic sheets, possibly suggesting magma accumulation during extension-dominated transtension.
U-Pb SHRIMP zircon and titanite ages on discordant felsic and mafic dikes and 40Ar/39Ar biotite and amphibole cooling ages record cooling between ca. 101-97 Ma, suggesting rapid cooling of the Fosdick migmatites and granites. Rotation of the strain field that created a pressure gradient for the accumulation of magma and initiation of detachment-related exhumation is inferred to have caused rapid cooling of the rocks in the Fosdick dome.McFadden, Rory. (2009). Melt transport and magma accumulation in a migmatite-cored gneiss dome, Fosdick Mountains, West Antarctica.. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/53724
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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