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The Kwakiutl totem pole and its symbolic value
The antiquity of the Northwest Coast Indian pole is the subject
of a great deal of controversy. A few viewpoints referring to that
topic are given. The symbolic value of the Kwakiutl totem pole is
examined with respect to art, style and culture; more generally
"primitive" art is considered as being completely integrated with the
major aspects of human existence. Theories concerning totemism are
described here and totemism among the Kwakiutl is examined with respect
to the social structure, mythology, the poles, and their interrelationships
Dielectric Function Tensor (1.5 eV to 9.0 eV), Anisotropy, and Band to Band Transitions of Monoclinic \u3cem\u3eÎČ\u3c/em\u3e-(Al\u3cem\u3e\u3csub\u3ex\u3c/sub\u3e\u3c/em\u3eGa\u3csub\u3e1â\u3cem\u3ex\u3c/em\u3e\u3c/sub\u3e)\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e (x †0.21) Films
A set of monoclinic ÎČ-(AlxGa1âx)2O3 films coherently grown by plasma-assisted molecular beam epitaxy onto (010)-oriented ÎČ-Ga2O3 substrates for compositions x †0.21 is investigated by generalized spectroscopic ellipsometry at room temperature in the spectral range of 1.5 eVâ9.0 eV. We present the composition dependence of the excitonic and band to band transition energy parameters using a previously described eigendielectric summation approach for ÎČ-Ga2O3 from the study by Mock et al. All energies shift to a shorter wavelength with the increasing Al content in accordance with the much larger fundamental band to band transition energies of Al2O3 regardless of crystal symmetry. The observed increase in the lowest band to band transition energy is in excellent agreement with recent theoretical predictions. The most important observation is that charge confinement in heterostructures will strongly depend on the growth condition due to the strongly anisotropic properties of the band to band transitions
An Essential Role for Interleukin 10 in the Function of Regulatory T Cells That Inhibit Intestinal Inflammation
A T helper cell type 1âmediated colitis develops in severe combined immunodeficient mice after transfer of CD45RBhigh CD4+ T cells and can be prevented by cotransfer of the CD45RBlow subset. The immune-suppressive activities of the CD45RBlow T cell population can be reversed in vivo by administration of an anti-transforming growth factor ÎČ antibody. Here we show that interleukin (IL)-10 is an essential mediator of the regulatory functions of the CD45RBlow population. This population isolated from IL-10âdeficient (IL-10â/â) mice was unable to protect from colitis and when transferred alone to immune-deficient recipients induced colitis. Treatment with an antiâmurine IL-10 receptor monoclonal antibody abrogated inhibition of colitis mediated by wild-type (WT) CD45RBlow CD4+ cells, suggesting that IL-10 was necessary for the effector function of the regulatory T cell population. Inhibition of colitis by WT regulatory T cells was not dependent on IL-10 production by progeny of the CD45RBhigh CD4+ cells, as CD45RBlow CD4+ cells from WT mice were able to inhibit colitis induced by IL-10â/â CD45RBhigh CD4+ cells. These findings provide the first clear evidence that IL-10 plays a nonredundant role in the functioning of regulatory T cells that control inflammatory responses towards intestinal antigens
Manual of Experimental Muscle Flap and Organ Transplantation Models in the Rat
No abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38478/1/12_ftp.pd
Role of defects in ultra-high gain in fast planar tin gallium oxide UV-C photodetector by MBE
We report ultra-high responsivity of epitaxial (SnxGa1-x)2O3 (TGO) Schottky UV-C photodetectors and experimentally identified the source of gain as deep-level defects, supported by first principles calculations. Epitaxial TGO films were grown by plasma-assisted molecular beam epitaxy on (-201) oriented n-type ÎČ-Ga2O3 substrates. Fabricated vertical Schottky devices exhibited peak responsivities as high as 3.5Ă104 A/W at -5V applied bias under 250nm illumination with sharp cutoff shorter than 280nm and fast rise/fall time in milliseconds order. Hyperspectral imaging cathodoluminescence (CL) spectra were examined to find the mid-bandgap defects, the source of this high gain. Irrespective of different tin mole fractions, the TGO epilayer exhibited extra CL peaks at the green band (2.20 eV) not seen in ÎČ-Ga2O3 along with enhancement of the blue emission-band (2.64 eV) and suppression of the UV emission-band. Based on hybrid functional calculations of the optical emission expected for defects involving Sn in ÎČ-Ga2O3, VGaâSn complexes are proposed as potential defect origins of the observed green and blue emission-bands. Such complexes behave as acceptors that can efficiently trap photogenerated holes and are predicted to be predominantly responsible for the ultra-high photoconductive gain in the Sn-alloyed Ga2O3 devices by means of thermionic emission and electron tunneling. Regenerating the VGaâSn defect complexes by optimizing the growth techniques, we have demonstrated a planar Schottky UV-C photodetector of the highest peak responsivity
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