The airborne lava-seawater interaction plume at Kilauea Volcano, Hawaii

Petrology igneous metamorphic and volcanic studies; medm0

Consistent modeling of the geodetic precession in Earth rotation

A highly precise model for the motion of a rigid Earth is indispensable to reveal the effects of non-rigidity in the rotation of the Earth from observations. To meet the accuracy goal of modern theories of Earth rotation of 1 microarcsecond (muas) it is clear, that for such a model also relativistic effects have to be taken into account. The largest of these effects is the so called geodetic precession. In this paper we will describe this effect and the standard procedure to deal with it in modeling Earth rotation up to now. With our relativistic model of Earth rotation Klioner et al. (2001) we are able to give a consistent post-Newtonian treatment of the rotational motion of a rigid Earth in the framework of General Relativity. Using this model we show that the currently applied standard treatment of geodetic precession is not correct. The inconsistency of the standard treatment leads to errors in all modern theories of Earth rotation with a magnitude of up to 200 muas for a time span of one century.Comment: 6 pages, 4 figures, 1 table, published in the Proceedings of the VII Hotine-Marussi Symposium, Chapter 4

Extracting information from S-curves of language change

It is well accepted that adoption of innovations are described by S-curves (slow start, accelerating period, and slow end). In this paper, we analyze how much information on the dynamics of innovation spreading can be obtained from a quantitative description of S-curves. We focus on the adoption of linguistic innovations for which detailed databases of written texts from the last 200 years allow for an unprecedented statistical precision. Combining data analysis with simulations of simple models (e.g., the Bass dynamics on complex networks) we identify signatures of endogenous and exogenous factors in the S-curves of adoption. We propose a measure to quantify the strength of these factors and three different methods to estimate it from S-curves. We obtain cases in which the exogenous factors are dominant (in the adoption of German orthographic reforms and of one irregular verb) and cases in which endogenous factors are dominant (in the adoption of conventions for romanization of Russian names and in the regularization of most studied verbs). These results show that the shape of S-curve is not universal and contains information on the adoption mechanism. (published at "J. R. Soc. Interface, vol. 11, no. 101, (2014) 1044"; DOI: http://dx.doi.org/10.1098/rsif.2014.1044)Comment: 9 pages, 5 figures, Supplementary Material is available at http://dx.doi.org/10.6084/m9.figshare.122178

A Fourier transform spectrometer for visible and near ultra-violet measurements of atmospheric absorption

The development of a prototype, ground-based, Sun-pointed Michelson interferometric spectrometer is described. Its intended use is to measure the atmospheric amount of various gases which absorb in the near-infrared, visible, and near-ultraviolet portions of the electromagnetic spectrum. Preliminary spectra which contain the alpha, 0.8 micrometer, and rho sigma tau water vapor absorption bands in the near-infrared are presented to indicate the present capability of the system. Ultimately, the spectrometer can be used to explore the feasible applications of Fourier transform spectroscopy in the ultraviolet where grating spectrometers were used exclusively

Bubble wall perturbations coupled with gravitational waves

We study a coupled system of gravitational waves and a domain wall which is the boundary of a vacuum bubble in de Sitter spacetime. To treat the system, we use the metric junction formalism of Israel. We show that the dynamical degree of the bubble wall is lost and the bubble wall can oscillate only while the gravitational waves go across it. It means that the gravitational backreaction on the motion of the bubble wall can not be ignored.Comment: 23 pages with 3 eps figure

A new method of alpha ray measurement using a Quadrupole Mass Spectrometer

We propose a new method of alpha($\alpha$)-ray measurement that detects helium atoms with a Quadrupole Mass Spectrometer(QMS). A demonstration is undertaken with a plastic-covered $^{241}$Am $\alpha$-emitting source to detect $\alpha$-rays stopped in the capsule. We successfully detect helium atoms that diffuse out of the capsule by accumulating them for one to 20 hours in a closed chamber. The detected amount is found to be proportional to the accumulation time. Our method is applicable to probe $\alpha$-emitting radioactivity in bulk material.Comment: 8 pages, 6 figure

The Undefeatable Opponent: How the Effective Administration of Water Is an Exception to Predeprivation Hearings Ordinarily Required by Due Process in \u3ci\u3eKeating v. Neb. Pub. Power District\u3c/i\u3e, 660 F.3d 1014 (8th Cir. 2011)

“Whiskey is for drinking, water is for fighting over.”1 [1. Famously attributed to author Mark Twain, but never authenticated.] But what happens when the only opponent is the rightful owner? With closing notices in hand, Gerard Keating and his neighbors asked themselves that same question. The Nebraska Department of Natural Resources issued closing notices to Keating and many other appropriators in Holt County, Nebraska, when stream flow in the Niobrara Watershed had become insufficient to satisfy the water needs of all surrounding appropriators. Instead of taking advantage of the postdeprivation hearing offered by the Department of Natural Resources, Keating and the other appropriators filed suit, claiming that Nebraska’s established water administration system violated their due process rights. Ultimately, the Eighth Circuit Court of Appeals found no due process violation of the appropriators’ rights, simply because the appropriators do not have a property interest in the waters of the state, which includes the Niobrara Watershed. To clarify the arguments discussed in Keating, this Note first provides an overview of Nebraska water administration, followed by a discussion of the property rights vested in public waters. This Note then analyzes the impracticality of predeprivation hearings for water administration, the state’s interest in quick administration of water use, and the challenge of providing sufficient due process while also preserving the water administration system. This Note then provides an overview of Keating and related case law. Thereafter, there is a discussion of the United States Supreme Court decisions which have ruled that a predeprivation hearing is necessary, and why those situations are inapplicable to the administration of water use. This discussion also describes established exceptions to the predeprivation hearing requirement and how Nebraska’s appropriation system does not violate due process. Finally, this Note concludes with how Keating’s and other similarly situated plaintiffs’ challenges to the water administration system are a result of misplaced expectations in appropriation permits and the minimal property rights held therein