938 research outputs found
God\u27s missional Spirit : the acts and agency of the Holy Spirit in the missional life
https://place.asburyseminary.edu/ecommonsatsdissertations/2424/thumbnail.jp
Functional Aspects of Primate Grooming
Author Institution: Division of Biological Sciences, University of Michigan, Ann Arbor, and New York Zoological SocietyExperimental walks with a tame primate reveal that free living primates are likely to be subject to frequent infestation by ticks. Observations on the grooming behavior of mangabeys, red colobus and blue monkeys demonstrated that self grooming is primarily directed to parts of the body not subjected to allo-grooming, and that its role is a cursory brushing away of loose particles rather than a detailed cleansing. Allo-grooming is directed towards the detailed cleansing of the skin and fur, and is associated with frequent particle removal. Length of body fur has a considerable influence on the amount of grooming different parts of the body receive. I suggest that sexual dimorphism, age, sex and dominance status are important in determining rates of ectoparasite acquisition, and so the amount of grooming individuals need and receive
Induced Ge Spin Polarization at the Fe/Ge Interface
We report direct experimental evidence showing induced magnetic moments on Ge
at the interface in an Fe/Ge system. Details of the x-ray magnetic circular
dichroism and resonant magnetic scattering at the Ge L edge demonstrate the
presence of spin-polarized {\it s} states at the Fermi level, as well as {\it
d} character moments at higher energy, which are both oriented antiparallel to
the moment of the Fe layer. Use of the sum rules enables extraction of the L/S
ratio, which is zero for the {\it s} part and for the {\it d}
component. These results are consistent with layer-resolved electronic
structure calculations, which estimate the {\it s} and {\it d} components of
the Ge moment are anti-parallel to the Fe {\it 3d} moment and have a magnitude
of .Comment: 4 pages, 5 figures, submitted to Phys. Rev. Let
Five meter diameter conical furlable antenna
An investigation was made to demonstrate that a 5-meter-diameter, furlable, conical reflector antenna utilizing a line source feed can be fabricated utilizing composite materials and to prove that the antenna can function mechanically and electrically as prototype flight hardware. The design, analysis, and testing of the antenna are described. An RF efficiency of 55% at 8.5 GHz and a surface error of 0.64 mm rms were chosen as basic design requirements. Actual test measurements yielded an efficiency of 53% (49.77 dB gain) and a surface error of 0.61 mm rms. Atmospherically induced corrosion of the reflector mesh resulted in the RF performance degradation. An assessment of the antenna as compared to the current state of the art technology was made. This assessment included cost, surface accuracy and RF performance, structural and mechanical characteristics, and possible applications
Local Environment of Ferromagnetically Ordered Mn in Epitaxial InMnAs
The magnetic properties of the ferromagnetic semiconductor In0.98Mn0.02As
were characterized by x-ray absorption spectroscopy and x-ray magnetic circular
dichroism. The Mn exhibits an atomic-like L2,3 absorption spectrum that
indicates that the 3d states are highly localized. In addition, a large
dichroism at the Mn L2,3 edge was observed from 5-300 K at an applied field of
2T. A calculated spectrum assuming atomic Mn2+ yields the best agreement with
the experimental InMnAs spectrum. A comparison of the dichroism spectra of MnAs
and InMnAs show clear differences suggesting that the ferromagnetism observed
in InMnAs is not due to hexagonal MnAs clusters. The temperature dependence of
the dichroism indicates the presence of two ferromagnetic species, one with a
transition temperature of 30 K and another with a transition temperature in
excess of 300 K. The dichroism spectra are consistent with the assignment of
the low temperature species to random substitutional Mn and the high
temperature species to Mn near-neighbor pairs.Comment: 10 pages, 4 figures, accepted by Applied Physics Letter
Emergent properties hidden in plane view: Strong electronic correlations at oxide interfaces
Finding new collective electronic states in materials is one of the
fundamental goals of condensed matter physics. Atomic-scale superlattices
formed from transition metal oxides are a particularly appealing hunting ground
for new physics. In bulk form, transition metal oxides exhibit a remarkable
range of magnetic, superconducting, and multiferroic phases that are of great
scientific interest and are potentially capable of providing innovative energy,
security, electronics and medical technology platforms. In superlattices new
states may emerge at the interfaces where dissimilar materials meet.
Here we illustrate the essential features that make transition metal
oxide-based heterostructures an appealing discovery platform for emergent
properties with a few selected examples, showing how charge redistributes,
magnetism and orbital polarization arises and ferroelectric order emerges from
heterostructures comprised of oxide components with nominally contradictory
behavior with the aim providing insight into the creation and control of novel
behavior at oxide interfaces by suitable mechanical, electrical or optical
boundary conditions and excitations.Comment: 16 pages, 5 figure
- …