Random pressure excitation of shells and statistical dependence effect of normal mode response

Structural stability of shells - random pressure excitation and statistical dependence of normal mode respons

Methods of Smile: A Science Seminar Course in Deliberate Education

Oregon State University’s Science and Math Investigative Learning Experiences (SMILE) Program is an enrichment program for minority and underrepresented K-12 students. Through an eight-year iterative process, SMILE has developed and refined a science seminar course that allows undergraduate and master’s degree students to explore science enrichment for youth. Students enrolled in the course are engaged in teaching and learning as a community of learners with a focus on service learning. The intended audience for the course is those students who are interested in working in educational settings with youth—as classroom teachers, science/mathematics professionals engaged in precollege outreach, and the like. The actual audience, though quite broad, represents those students who want to be better prepared as effective science educators in their various career roles. This article provides the context for the course, defines and examines deliberate education as illustrated by the structure and activities of the Methods of SMILE seminar course, highlights the elements of an effective community of learners as demonstrated through it, details the specific strategies and activities of it, and summarizes the next steps in identifying its impact in transforming the participants’ college experiences

Nanotechnology and cancer

The biological picture of cancer is rapidly advancing from models built from phenomenological descriptions to network models derived from systems biology, which can capture the evolving pathophysiology of the disease at the molecular level. The translation of this (still academic) picture into a clinically relevant framework can be enabling for the war on cancer, but it is a scientific and technological challenge. In this review, we discuss emerging in vitro diagnostic technologies and therapeutic approaches that are being developed to handle this challenge. Our discussion of in vitro diagnostics is guided by the theme of making large numbers of measurements accurately, sensitively, and at very low cost. We discuss diagnostic approaches based on microfluidics and nanotechnology. We then review the current state of the art of nanoparticle-based therapeutics that have reached the clinic. The goal of the presentation is to identify nanotherapeutic strategies that are designed to increase efficacy while simultaneously minimizing the toxic side effects commonly associated with cancer chemotherapies

Accuracy of the Kirchoff formula in determining acoustic shielding with the use of a flat plate

It has been suggested that if jet engines of aircraft were placed at above the wing instead of below it, the wing would provide a partial shielding of the noise generated by the engines relative to observers on the ground. The shielding effects of an idealized three-dimensional barrier in the presence of an idealized engine noise source was predicted by the Kirchoff formula. Based on the good agreement between experimental measurements and the numerical results of the current study, it was concluded that the Kirchoff approximation provides a good qualitative estimate of the acoustic shielding of a point source by a rectangular flat plate for measurements taken in the far field of the flat plate at frequencies ranging from 1 kHz to 20 kHz. At frequencies greater than 4 kHz the Kirchoff approximation provides accurate quantitative predictions of acoustic shielding

Integrity bases for local invariants of composite quantum systems

Unitary group branchings appropriate to the calculation of local invariants of density matrices of composite quantum systems are formulated using the method of $S$-function plethysms. From this, the generating function for the number of invariants at each degree in the density matrix can be computed. For the case of two two-level systems the generating function is $F(q) = 1 + q + 4q^{2} + 6 q^{3} + 16 q^{4} + 23 q^{5} + 52 q^{6} + 77 q^{7} + 150 q^{8} + 224 q^{9} + 396 q^{10} + 583 q^{11}+ O(q^{12})$. Factorisation of such series leads in principle to the identification of an integrity basis of algebraically independent invariants. This note replaces Appendix B of our paper\cite{us} J Phys {\bf A33} (2000) 1895-1914 (\texttt{quant-ph/0001076}) which is incorrect.Comment: Latex, 4 pages, correcting Appendix B of quant-ph/0001076 Error in $F(q)$ corrected and conclusions modified accordingl

Stellar ultraviolet colors and interstellar extinction

A sample of celescope results is studied. Most of the sample stars belong to the Orion and Vela regions. Stars with visual excess E(B-V) less than 0.05 are selected in order to derive relationships of intrinsic color index versus spectral type. The resulting intrinsic color-color relations are compared with existing blanketed and unblanketed model calculations. Finally, the preceding intrinsic relations are utilized to derive some results on interstellar extinction. Owing to the rather large scatter in the celescope data, the Vela stars give the more significant results because their visible excess E(B-V) is, in general, larger than that for the Orion stars

Cosmic Strings, Zero Modes and SUSY breaking in Nonabelian N=1 Gauge Theories

We investigate the microphysics of cosmic strings in Nonabelian gauge theories with N=1 supersymmetry. We give the vortex solutions in a specific example and demonstrate that fermionic superconductivity arises because of the couplings and interactions dictated by supersymmetry. We then use supersymmetry transformations to obtain the relevant fermionic zero modes and investigate the role of soft supersymmetry breaking on the existence and properties of the superconducting strings.Comment: 12 pages, RevTex, submitted to Phys. Rev.

Bones, Bombs and Break Points: The Geography of Economic Activity

We consider the distribution of economic activity within a country in light of three leading theories - increasing returns, random growth, and locational fundamentals. To do so, we examine the distribution of regional population in Japan from the Stone Age to the modern era. We also consider the Allied bombing of Japanese cities in WWII as a shock to relative city sizes. Our results support a hybrid theory in which locational fundamentals establish the spatial pattern of relative regional densities, but increasing returns may help to determine the degree of spatial differentiation. One implication of these results is that even large temporary shocks to urban areas have no long-run impact on city size.

Do Factor Endowments Matter for North-North Trade?

The dominant paradigm of world trade patterns posits two principal features. Trade between North and South arises due to traditional comparative advantage, largely determined by differences in endowment patterns. Trade within the North, much of it intra-industry trade, is based on economies of scale and product differentiation. The paradigm specifically denies an important role for endowment differences in determining North-North trade. This paper provides the first sound empirical examination of this question. We demonstrate that trade in factor services among countries of the North is systematically related to endowment differences and large in economic magnitude. Intra-industry trade, rather than being a puzzle for a factor endowments theory, is instead the conduit for a great deal of this factor service trade.