Analysis of star pair latitudes

Star pair latitude observations forming the basis for the pole positions reported by the International Polar Motion Service (IPMS) are processed to produce a mean pole position. However, the time series of raw observations contains high frequency information which is lost in the calculation of the mean pole. Analysis of 2931 star pair observations reveals a possible large excitation at one cycle per solar day. The average power level in the frequency band of the tesseral tides is seen to be high, although the peaks do not occur at the expected tidal frequencies

On Cellular Algebras with Jucys Murphy Elements

We study analogues of Jucys-Murphy elements in cellular algebras arising from repeated Jones basic constructions. Examples include Brauer and BMW algebras and their cyclotomic analogues.Comment: Improved and reorganized exposition. Some new result

Syntactic Topic Models

The syntactic topic model (STM) is a Bayesian nonparametric model of language that discovers latent distributions of words (topics) that are both semantically and syntactically coherent. The STM models dependency parsed corpora where sentences are grouped into documents. It assumes that each word is drawn from a latent topic chosen by combining document-level features and the local syntactic context. Each document has a distribution over latent topics, as in topic models, which provides the semantic consistency. Each element in the dependency parse tree also has a distribution over the topics of its children, as in latent-state syntax models, which provides the syntactic consistency. These distributions are convolved so that the topic of each word is likely under both its document and syntactic context. We derive a fast posterior inference algorithm based on variational methods. We report qualitative and quantitative studies on both synthetic data and hand-parsed documents. We show that the STM is a more predictive model of language than current models based only on syntax or only on topics

Summary of recent investigations of inlet flow distortion effect on engine stability

A review is presented of recent experimental results, analytical procedures and test techniques employed to evaluate the effects of inlet flow distortion on the stability characteristics of representative afterburning turbofan and turbojet compression systems. Circumferential distortions of pressure and temperature, separately and in combination are considered. Resulting engine sensitivity measurements are compared with predictions based on simplified parallel compressor models and with several distortion descriptor parameters

An Experiment in the Teaching of Industrial Physics

While we as teachers of engineering physics comparing ourselves with ourselves and grading objective tests of many types and stripes are inclined to think that our teaching and student product are satisfactory, there may be criteria which our instruction is not meeting. Impressed with this possibility I have made an analysis of my findings obtained from interviews with my own students, deans of engineering schools and engineers in the practice of their profession. The results of these studies are definite and specific

Polar motion spectra based upon Doppler IPMS and BIH data

In comparing polar motion spectra, an oscillation was found at 1.3 cpy which might be due to an Eulerian motion of the solid inner core. An extended 15-year data set was filtered and analyzed to yield a Chandler peak with a period 430.8 solar days and a full width at half-maximum of 0.7 days (Q-600). The data was reanalyzed in overlapping 3-year segments and indicates that the excitation of the Chandler wobble is a discrete process and that periods as long as three years occur in which the driving mechanism is essentially quiescent

Analysis of daily latitude variations

The daily latitude measurements of the International polar motion service are analyzed. The results indicate that the annual polar oscillation is probably due to local phenomena with amplitudes varying from 0.05 to 0.15 min. Within the resolution of the residuals (150 cm), there is no indication of the sharp changes which might be associated with earthquake effects. Then, applying Schuster's test to a periodogram of the residuals indicates that there are probably several processes occurring at amplitudes between 0.007 and 0.03 min whose solution awaits a more precise measurement technique

CaM KK Mediates MDM2 Activation in LNCaP Cells

Abstract Agonists and hormones that cause an influx of calcium in LNCaP prostate cancer cells activate the calcium/calmodulin-dependent protein kinase (CaM Kinase) pathway and AKT phosphorylation. CaM KK and AKT are essential for promoting LNCaP cell survival. AKT phosphorylation of MDM2 protein may negatively regulate the tumor suppressor protein, p53. CaM KK and AKT have yet to be demonstrated as upstream regulators of MDM2 and p53 in LNCaP cells. Our goals were to examine the ability of carbachol and testosterone to stimulate MDM2 phosphorylation, its association with p53, and whether CaM KK is upstream of MDM2. Stimulation of LNCaP cells with carbachol increased MDM2 phosphorylation that was blocked by the CaM KK inhibitor, STO-609 as well as the AKT inhibitor, AKT-X. Similarly, testosterone also increased MDM2 phosphorylation through CaM KK and AKT. The requirement for CaM KK upstream of MDM2 was also examined using siRNA knockdown of CaM KK. Carbachol treatment of cells triggered phosphorylation of MDM2 that was blocked in cells transfected with siRNA against CaM KK. To assess the biochemical significance of signaling through CaM KK and MDM2 in LNCaP cells we assayed MDM2 association with p53. Carbachol stimulated MDM2 association with p53 in a manner that was dependent upon CaM KK. Our results suggest that carbachol treatment of LNCaP cells promoted phosphorylation of MDM2 and its association with p53 through CaM KK

An information theory approach to the density of the earth

Information theory can develop a technique which takes experimentally determined numbers and produces a uniquely specified best density model satisfying those numbers. A model was generated using five numerical parameters: the mass of the earth, its moment of inertia, three zero-node torsional normal modes (L = 2, 8, 26). In order to determine the stability of the solution, six additional densities were generated, in each of which the period of one of the three normal modes was increased or decreased by one standard deviation. The superposition of the seven models is shown. It indicates that current knowledge of the torsional modes is sufficient to specify the density in the upper mantle but that the lower mantle and core will require smaller standard deviations before they can be accurately specified