Convection without eddy viscosity: An attempt to model the interiors of giant planets

In the theory of hydrostatic quasi-geostrophic flow in the Earth's atmosphere the principal results do not depend on the eddy viscosity. This contrasts with published theories of convection in deep rotating fluid spheres, where the wavelength of the fastest growing disturbance varies as E sup 1/3, where E, the Ekman number, is proportional to the eddy viscosity. A new theory of quasi-columnar motions in stably stratified fluid spheres attempts to capture the luck of the meteorologists. The theory allows one to investigate the stability of barotropic and baroclinic zonal flows that extend into the planetary interior. It is hypothesized that the internal heat Jupiter and Saturn comes out not radially but on sloping surfaces defined by the internal entropy distribution. To test the hypothesis one searches for basic states in which the wavelength of the fastest-growing disturbance remains finite as E tends to zero, and is which the heat flux vector is radially outward and poleward

Lunar studies

Two research projects to classify lunar photographic images are reported. The feasibility of using polarimetry to study large scale features on the moon was investigated. A system was built that measured polarization by subtracting two film images taken through perpendicular Polaroid filters, however, no new boundaries were discovered in the pictures which are not already discernable in ordinary photographs. The present status and equipment of a microfiche library system which would allow easy access to selected lunar photographs from all space missions is also reported

Science support for the Earth radiation budget sensor on the Nimbus-7 spacecraft

Experimental data supporting the Earth radiation budget sensor on the Nimbus 7 Satellite is given. The data deals with the empirical relations between radiative flux, cloudiness, and other meteorological parameters; response of a zonal climate ice sheet model to the orbital perturbations during the quaternary ice ages; and a simple parameterization for ice sheet ablation rate

Thermal balance of the atmospheres of Jupiter and Uranus

Two-dimensional, radiative-convective-dynamical models of the visible atmospheres of Jupiter and Uranus are presented. Zonally-averaged temperatures and heat fluxes are calculated numerically as functions of pressure and latitude. In addition to radiative heat fluxes, the dynamical heat flux due to large-scale baroclinic eddies is included and is parametrized using a mixing length theory which gives heat fluxes similar to those of Stone. The results for Jupiter indicate that the internal heat flow is non-uniform in latitude and nearly balances the net radiative flux leaving the atmosphere. The thermal emission is found to be uniform in latitude in agreement with Pioneer and Voyager observations. Baroclinic eddies are calculated to transport only a small amount of the meridional heat flow necessary to account for the uniformity of thermal emission with latitude. The bulk of the meridional heat transfer is found to occur very deep in the stable interior of Jupiter as originally proposed by Ingersoll and Porco. The relative importance of baroclinic eddies vs. internal heat flow in the thermal balance of Uranus depends on the ratio of emitted thermal power to absorbed solar power. The thermal balance of Uranus is compared to that of Jupiter for different values of this ratio

Comments on "Evidence for the distribution of angular velocity inside the sun and stars."

I want to discuss the question of whether the oblateness measurements that Dicke and Goldenberg [1967] made do indicate that the core of the sun is rotating rapidly, or whether there is an equally attractive alternate possibility. Dicke and Goldenberg looked at the shape of the sun in visible light, and there are really three ways that the sun might look oblate in visible light. The first possibility is that the equipotentials. gravitational plus centrifugal. are oblate, which would be the case if the interior of the sun were rotating rapidly. The second and third are variations of the possibility that the solar equator is somehow hotter than the poles. If the equator were hotter, it would also be brighter, and this might be confused with an oblateness because of the limitations of seeing in the earth's atmosphere

Novel Therapeutic Strategies for Treatment of Castration-Resistant Prostate Cancer

Prostate cancer (PCa) remains the most commonly diagnosed solid tumor and is the third leading cause of cancer-related death in United States men. While androgen deprivation therapy is the current standard-of-care treatment for metastatic PCa, most patients eventually relapse and develop castration-resistant (CR) tumors, for which there is currently no effective treatment. Therefore, synthesis of novel therapeutic agents and identification of alternative target proteins are necessary to improve treatment. Herein, I investigate the efficacy of novel imidazopyridine and statin derivatives as alternative therapeutic compounds. These molecules not only inhibit androgen receptor signaling, but also block activation of the AKT axis, a mechanism of androgen independence. Furthermore, I investigate the role of p66Shc, a 66 kDa Src and collagen homologue oxidase, in the mechanism of PCa metastatic progression. p66Shc is elevated in clinical PCa as well as multiple PCa cell lines which correspond with advanced CR PCa. Additionally, p66Shc has been demonstrated to promote proliferation in PCa cell lines via generation of reactive oxygen species (ROS). This study is the first to demonstrate p66Shc also regulates PCa cell migration through ROS production and identifies key ROS-sensitive proteins pivotal to its mechanism. Understanding how p66Shc promotes migration may lead to the identification of alternative therapeutic targets for suppression of CR PCa metastatic activity. Overall, this study seeks to support future efforts to generate therapeutic compounds for treatment of metastatic CR PCa

Saturn's aurora observed by the Cassini camera at visible wavelengths

The first observations of Saturn's visible-wavelength aurora were made by the Cassini camera. The aurora was observed between 2006 and 2013 in the northern and southern hemispheres. The color of the aurora changes from pink at a few hundred km above the horizon to purple at 1000-1500 km above the horizon. The spectrum observed in 9 filters spanning wavelengths from 250 nm to 1000 nm has a prominent H-alpha line and roughly agrees with laboratory simulated auroras. Auroras in both hemispheres vary dramatically with longitude. Auroras form bright arcs between 70 and 80 degree latitude north and between 65 and 80 degree latitude south, which sometimes spiral around the pole, and sometimes form double arcs. A large 10,000-km-scale longitudinal brightness structure persists for more than 100 hours. This structure rotates approximately together with Saturn. On top of the large steady structure, the auroras brighten suddenly on the timescales of a few minutes. These brightenings repeat with a period of about 1 hour. Smaller, 1000-km-scale structures may move faster or lag behind Saturn's rotation on timescales of tens of minutes. The persistence of nearly-corotating large bright longitudinal structure in the auroral oval seen in two movies spanning 8 and 11 rotations gives an estimate on the period of 10.65 $\pm$0.15 h for 2009 in the northern oval and 10.8$\pm$ 0.1 h for 2012 in the southern oval. The 2009 north aurora period is close to the north branch of Saturn Kilometric Radiation (SKR) detected at that time.Comment: 39 pages, 8 figures, 1 table, 6 supplementary movies, accepted to Icaru

Lunar and planetary studies

This grant supports the core program in planetary astronomy at Caltech. The research includes observations in the IR, sub-mm, mm and cm wavelengths at national and Caltech observatories with a strong emphasis on integrating the observations with spacecraft data and with models of atmospheric structure, dynamics and chemistry. Muhleman's group made extensive observations of Saturn, Uranus and Neptune which are being interpreted in terms of deep atmospheric structures which are obvious in the 2 and 6 cm maps of Saturn and Uranus. The microwave measurements are one of the few sources of information below the 2 bar level. Goldreich is investigating the dynamics of narrow rings with postdoctoral fellow, Pierre-Yves Longaretti. Their work has focused on the role of collisional stresses on the precession of the rings, since the Voyager radio science results imply that the previous model based on the ring's self-gravity is not the entire story. In addition Borderies, Goldreich and Tremaine have completed an investigation of the dynamics of the Encke division in Saturn's A ring

High Water Marks

Incentive fees for money managers are frequently accompanied by high-water mark provisions that condition the payment of the performance fee upon exceeding the previously achieved maximum share value. In this paper, we show that hedge fund performance fees are valuable to money managers, and conversely, represent a claim on a significant proportion of investor wealth. The high-water mark provisions in these contracts limit the value of the performance fees. We provide a closed-form solution to the cost of the high-water mark contract under certain conditions. Our results provide a framework for valuation of a hedge fund management company.

Is the Supply of Mathematics and Science Teachers Sufficient?

This study seeks to empirically ground the debate over mathematics/science teacher shortages, and evaluate the extent to which there is, or is not, a sufficient supply of teachers in these fields. Our analyses of nationally representative data from multiple sources show that mathematics and science are the most difficult-to-staff fields, but the factors behind these problems are complex. There are multiple sources of new teachers; those with education degrees are a minor source compared to those with degrees in mathematics and science, and the reserve pool. Over the past two decades, graduation requirements, student course taking, and teacher retirements have all increased for mathematics and science, yet the new supply has more than kept pace. However, when preretirement teacher attrition is factored in, there is a much tighter balance between supply and demand. Unlike fields such as English, for mathematics/science there is not a large cushion of new supply relative to losses—resulting in staffing problems in schools with higher turnover