The normal and parametric resonances of a framed structure under periodic excitation: An alternative explanation of “snake-like” vibration of Volgograd Bridge

We study the linear stability of two superposed layers of viscous, immiscible fluids of diﬀerent densities. The whole system is subject to horizontal quasi-periodic oscillation with two incommensurates frequencies ω1 and ω2. The spectral method and Floquet’s theory combined with Runge-Kutta method are used to solve numericelly the linear problem. We analyse the influence of the frequencies ratio$ \omega = {{{\omega _1}} \over {{\omega _2}}} $, on the mariginal stability. The numerical solution shows that the quasi-periodic excitation has a stabilizing or a destabilizing eﬀect on the Kelvin-Helmholtz instability as well as in the parametric resonances depending on the frequency ratio and the amplitudes ratio $ \alpha = {{{\alpha _2}} \over {{\alpha _1}}} $.

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Association of pituitary adenoma with neuronal christoma: A TEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016889x ◽

1994 ◽

Vol 52 ◽

pp. 232-233

Author(s):

Eva Horvath ◽

Kalman Kovacs ◽

B. W. Scheithauer ◽

R. V. Lloyd ◽

H. S. Smyth

Keyword(s):

Growth Hormone ◽

Pituitary Adenoma ◽

Pituitary Tumor ◽

Nervous Tissue ◽

Alternative Explanation ◽

Growth Hormone Releasing Hormone ◽

Cell Hyperplasia ◽

Releasing Hormone ◽

Secretory Neurons

The association of a pituitary adenoma with nervous tissue consisting of neuron-like cells and neuropil is a rare abnormality. In the majority of cases, the pituitary tumor is a chromophobic adenoma, accompanied by acromegaly. Histology reveals widely variable proportions of endocrine and nervous tissue in alternating or intermingled patterns. The lesion is perceived as a composite one consisting of two histogenetically distinct parts. It has been suggested that the neuronal component, morphologically similar to secretory neurons of the hypothalamus, may initiate adenoma formation by releasing stimulatory substances. Immunoreactivity for growth hormone releasing hormone (GRH) in the neuronal component of some cases supported this view, whereas other findings such as consistent lack of growth hormone (GH) cell hyperplasia in the lesions called for alternative explanation.Fifteen tumors consisting of a pituitary adenoma and a neuronal component have been collected over a 20 yr. period. Acromegaly was present in 11 patients, was equivocal in one, and absent in 3.

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Attitude Accessibility as an Alternative Explanation for How Inoculation Confers Resistance

Communication Monographs ◽

10.1080/03637750302474 ◽

2003 ◽

Vol 70 (1) ◽

pp. 1-1 ◽

Cited By ~ 15

Author(s):

Michael Pfau ◽

David Roskos-Ewoldsen ◽

Michelle Wood ◽

Suya Yin ◽

Jaeho Cho ◽

...

Keyword(s):

Alternative Explanation ◽

Attitude Accessibility

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Does the Name-Race Implicit Association Test Measure Racial Prejudice?

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000093 ◽

2011 ◽

Vol 58 (4) ◽

pp. 271-277 ◽

Cited By ~ 26

Author(s):

Don van Ravenzwaaij ◽

Han L. J. van der Maas ◽

Eric-Jan Wagenmakers

Keyword(s):

Diffusion Model ◽

Implicit Association Test ◽

Alternative Explanation ◽

Group Membership ◽

Racial Prejudice ◽

Decision Time ◽

Association Test ◽

Implicit Association ◽

Model Decomposition ◽

Test Measure

Research using the Implicit Association Test (IAT) has shown that names labeled as Caucasian elicit more positive associations than names labeled as non-Caucasian. One interpretation of this result is that the IAT measures latent racial prejudice. An alternative explanation is that the result is due to differences in in-group/out-group membership. In this study, we conducted three different IATs: one with same-race Dutch names versus racially charged Moroccan names; one with same-race Dutch names versus racially neutral Finnish names; and one with Moroccan names versus Finnish names. Results showed equivalent effects for the Dutch-Moroccan and Dutch-Finnish IATs, but no effect for the Finnish-Moroccan IAT. This suggests that the name-race IAT-effect is not due to racial prejudice. A diffusion model decomposition indicated that the IAT-effects were caused by changes in speed of information accumulation, response conservativeness, and non-decision time.

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