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Steroidogenesis-inducing protein: An enigmatic protein with multiple biological functions
Presented on October 9, 2008 from 11:00 AM – 12:00 PM in room L1205, Ford Environmental Science & Technology Building (ES&T) on the Georgia Tech campus.Runtime: 45:57 minutesSIP was isolated and characterized from human ovarian follicular fluid in our laboratory on the basis of its profound effects on steroid production in testicular, ovarian and adrenal cells. Later studies showed that SIP is also a potent mitogen and stimulated DNA synthesis in testicular Leydig cells, ovarian granulosa cells and in cell lines derived from ovarian epithelial carcinomas. Partial amino acid sequence analysis of this protein revealed that SIP is a novel protein which shows similarities with immunoglobulins and with a recently characterized DING family of proteins. Antibodies raised against specific SIP peptide blocked the activity of SIP on DNA synthesis and on steroid production in testicular cells. Using these antibodies we also determined the expression of SIP in different tissues and cell lines including prostate cancer cells. A SIP protein was detected in the rat testes, ovarian granulosa cells, ovarian epithelial cancer cell lines and in several prostate cancer cell lines. Furthermore, treatment with purified SIP resulted in induction of proliferation of prostate cancer cells similar to that seen in ovarian cancer cells and in other cell types. Based on these studies we hypothesize that SIP is produced by prostate cancer cells in the advanced stages of disease and serves as an autocrine regulator of cell proliferation in these cells. Furthermore, we hypothesize that SIP may exert its steroidogenic effects on these cells resulting in synthesis of steroids which may serve as ligands for AR and hence may lead to insensitivity to exogenous androgen
On Distribution Asset Management: Development of Replacement Strategies
Presented at IEEE PES PowerAfrica 2007 Conference and Exposition. ©2007 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Digital Object Identifier: 10.1109/PESAFR.2007.4498062The components of electricity networks are ageing. It is expected that within a horizon of 15 years, the performance will deteriorate significantly, while the costs for operating the networks will increase enormously. The main problem is that a significant part of the population of the assets is installed in the same period, resulting in a highly concentrated number of failures in a short time. The currently applied replacement strategy has to be revisited, in order to accommodate the effects of ageing assets: higher maintenance costs, high failure rates, and a steep increase of capital expenditure (CAPEX).The work reported here was supported by a large number of utilities in North America and the US Department of Energy under award number DE-FC02-04CH11237
Comparison of three Monte Carlo conformational search strategies for a proteinlike homopolymer model: Folding thermodynamics and identification of low-energy structures
©2000 American Institute of PhysicsThe electronic version of this article is the complete one and can be found online at: http://link.aip.org/link/?JCPSA6/113/5065/1DOI:10.1063/1.1289533Entropy sampling Monte Carlo, the replica method, and the classical Metropolis scheme were applied in numerical studies of the collapse transition in a simple face-centered cubic lattice polymer. The force field of the model consists of pairwise, contact-type, long-range interactions and a short-range potential based on the β -sheet definition assumed in the model. The ability to find the lowest energy conformation by various Monte Carlo methods and the computational cost associated with each was examined. It is shown that all of the methods generally provide the same picture of the collapse transition. However, the most complete thermodynamic description of the transition derives from the results of entropy sampling Monte Carlo simulations, but this is the most time-consuming method. The replica method is shown to be the most effective and efficient in searching for the lowest energy conformation. The possible consequences of these findings for the development of simulation strategies for the folding of model proteins are discussed briefly
Loss and heat generation in piezoelectric transducers
Issued as final reportUnited States. NavyUnited States. Naval Undersea Warfare Cente
Valence excitations in individual single-wall carbon nanotubes
©2002 American Institute of Physics. The electronic version of this article is the complete one and can be found online at: http://link.aip.org/link/?APPLAB/80/2982/1DOI:10.1063/1.1469685We report on measurements of the plasmon losses of individual single-wall carbon nanotubes by electron energy-loss spectroscopy in a high-resolution transmission electron microscope. The experimental data are compared to simulated excitation probabilities calculated using the hydrodynamic theory of the interaction between a probe electron and a two-dimensional quasifree electron gas confined on a cylindrical shell. Depending on the nanotube geometry, the first- or the second-order oscillation mode dominates the loss spectrum. The resonance energy of the dominant resonance mode is found to depend on the radius of the nanotube
NSDL EduPak: An Open Source Education Repository Solution
4th International Conference on Open RepositoriesThis presentation was part of the session : Conference PostersEducational organizations and institutions focused on establishing specialized digital collections, conducting educational research, or providing students, teachers and instructors with discipline-oriented pedagogical products and tools require basic technology to begin building educational digital repositories. To help meet these needs, the National Science Digital Library (NSDL) has announced the release of NSDL EduPak. Specifically designed for education, NSDL EduPak packages technology for digital storage, access, and workflow into a convenient bundle. This poster reviews three core EduPak components with examples of how they are used by education communities.National Science Foundatio
Student Project: International Offset for Space - Offsets Enable Planetary Probe Technology Exchanges Internationally
This presentation was part of the session : Poster SessionsSixth International Planetary Probe WorkshopOffset or industrial participation is a practice that is part of many large international transactions. In the event of a large international transaction involving the purchase of a product (e.g.: equipment or services), the company selling the product, is typically required to compensate the purchasing country for a perceived loss to the economy of the purchasing country. This compensation is called offset. Other terms for offset include industrial participation or industrial cooperation, and there are others. Offset is a legal or formal requirement for many large sales by companies to most foreign governments. Exceptions include the United States and Japan which have other methods of getting the compensation for perceived loss to their economies. Over the past 25 years, the number of countries practicing offset in international sales have increased tenfold to over 150 countries. As estimated by offset associations (i.e.: GOCA, DMA, etc.) offset accounts for 10% to 15% of world trade, which translates to about 1 trillion dollars in world trade per year.
Offset has great potential to be used for interplanetary probe applications.
Help fund joint interplanetary probe missions between countries.
Provide launch services.
Stimulate research and development of sensors within universities.
Increased international collaboration between seller and buyer countries.
Build stronger bonds within the international scientific community.
This is a student project. Our objective is to promote the use of international offset to further the development of interplanetary probe missions.NASA, Ames Research Center ; Alliance of Commercial Enterprises and Education for Space ; San Jose State Universit
A Value Proposition for Lunar Architectures Utilizing Propellant Re-supply Capabilities
58th International Astronautical Congress September 2007, Hyderabad, India.The NASA Exploration Systems Architecture Study (ESAS)ⁱⁱ produced a transportation
architecture for returning humans to the moon affordably and safely while using commercial
services for tasks such as cargo delivery to low earth orbit (LEO). Another potential utilization
of commercial services is the delivery of cryogenic propellants to LEO for use in lunar
exploration activities. With in-space propellant re-supply available, there is the potential to
increase the payload that can be delivered to the lunar surface, increase lunar mission
durations, and enable a wider range of lunar missions. The addition of on-orbit propellant resupply
would have far-reaching effects on the entire exploration architecture. Currently 70% of
the weight delivered to LEO by the cargo launch vehicle is propellant needed for the TLI burn.
This is a considerable burden and significantly limits the design freedom of the architecture.
The ability of commercial providers to deliver cryogenic propellants to LEO may provide for a
less expensive and better performing lunar architecture
Nanopropeller arrays of zinc oxide
©2004 American Institute of Physics. The electronic version of this article is the complete one and can be found online at: http://link.aip.org/link/?APPLAB/84/2883/1DOI:10.1063/1.1702137Polar surface dominated ZnO nanopropeller arrays were synthesized by a two-step high temperature solid-vapor deposition process. The axis of the nanopropellers is a straight nanowire along the c axis and enclosed by {20} surfaces, which grew first; the sixfold symmetric nanoblades are later formed along the crystallographic equivalent a axes (20) perpendicular to the nanowire; and the array is formed by epitaxial growth of nanoblades on the nanowire. The top surface of the nanoblade is the Zn terminated +c plane, showing surface steps and possible secondary growth of nanowires due to higher self-catalytic activity, while the back surface is the oxygen-terminated –c plane, which is smooth and inert