Research reports: 1987 NASA/ASEE Summer Faculty Fellowship Program

For the 23rd consecutive year, a NASA/ASEE Summer Faculty Fellowship Program was conducted at the Marshall Space Flight Center (MSFC). The program was conducted by the University of Alabama in Huntsville and MSFC during the period 1 June to 7 August 1987. Operated under the auspices of the American Society for Engineering Education, the MSFC program, as well as those at other NASA Centers, was sponsored by the Office of University Affairs, NASA Headquarters, Washington, D.C. The basic objectives of the program are: (1) to further the professional knowledge of qualified engineering and science faculty members; (2) to stimulate an exchange of ideas between participants and NASA; (3) to enrich and refresh the research and teaching activities of the participant's institutions; and (4) to contribute to the research objectives of the NASA Centers. This document is a compilation of Fellow's reports on their research during the Summer of 1987

Phase I Cultural Resources Investigations at Justiceburg Resevoir on the Double Mountain Fork of the Brazos River, Garza and Kent Counties, Texas Volume II

The prehistoric site descriptions are divided into three sections: Garza County, Kent County, and Isolated Finds. All sites are described fully in a telegraphic format in order to conserve space. The descriptions are organized by county in alphabetical order and in numerical order of site within each county. Information for each site 1s organized into six headings: location, description, features, cultural materials observed/collected, shovel test data, and assessment/recommendations. The determination of the percentage of the site remaining intact is based on in-field observations of the postulated original areal extent of the site versus what is still potentially intact. Assessments are based on each site\u27s individual merits and are stated in terms of eligibility for listing on the National Register of Historic Places. These assessments were made by the Project Archeologist and the Principal Investigator based on a site-by-site review. Two categories of eligibility include: potentially eligible (sites with excellent to unknown research potential) , and not eligible (sites with little or no further research potential). Research potential is derived from each site I s potential to contribute to the resolution of the questions posed in the Research Design (Chapter 5). While most of the research potential categories are reasonably clear, the unknown category should be more fully explained. Sites with unknown potential are those that are buried, lack exposed features, and failed to yield temporally or functionally diagnostic materials. The unknownII designation refers to the inability (based on extant data) to specify which research questions a site may appropriately address rather than a lack of any research potential. Assessments also may refer to exotics. This term is used to identify materials or artifacts that were imported into the local area. Included are such items as obsidian, Alibates agate, Tecovas jasper, and nonlocal ceramics. Recommendations are provided on the basis of each site\u27s assessment. These do not consider the suggested sampling strategy described in Chapter 13, Recommendations/Treatment Plan. Isolated Finds were thoroughly documented in the field and were assigned trinomial site numbers to facilitate record Jceeping; however, they are not felt to be worthy of extended descriptions for reporting purposes. Therefore, this category of sites is treated in highly abbreviated form in a separate section following the site descriptions. Information provided for Isolated Finds includes: site number, location, landform, elevation, area, description, and material type. Isolated finds are defined as any single surface artifact or feature with no associated materials or features, or surface sites with a density of cultural materials less than one item in 20 rna. These finds generally are highly disturbed, redeposited, or lack intact context. No shovel testing was done at Isolated Finds, except at sites 41GR411, 41GR482, 41GRS19, 41GRS32, 41KT46, and 41KT71, where all tests excavated were negative. Only three of these Isolated Finds are dated. These sites are considered to retain little interpretive value beyond the survey level, and none require further work. Because of this, Isolated Finds are not considered eligible for listing on the National Register of Historic Places. Finally, abbreviations are used throughout the site descriptions. Those referring to roads, distances, elevations, and cardinal directions are self-explanatory. However, two others require explanation. GRC refers to Grand River Consultants, Inc., a firm located in Grand River, Colorado, which performed limited archeological survey at Justiceburg in 1982. NRHP refers to the National Register of Historic Places; this phrase is abbreviated to save space since it must be used in the assessments of each individual site

A Synthetic Form of Frizzled 8-Associated Antiproliferative Factor Enhances p53 Stability through USP2a and MDM2

Frizzled 8-associated Antiproliferative Factor (APF) is a sialoglycopeptide urinary biomarker of interstitial cystitis/painful bladder syndrome (IC/PBS), a chronic condition of unknown etiology with variable symptoms that generally include pelvic and/or perineal pain, urinary frequency, and urgency. We previously reported that native human APF suppresses the proliferation of normal bladder epithelial cells through a mechanism that involves increased levels of p53. The goal of this study was to delineate the regulatory mechanism whereby p53 expression is regulated by APF. Two APF-responsive cell lines (T24 bladder carcinoma cells and the immortalized human bladder epithelial cell line, TRT-HU1) were treated with asialo-APF (as-APF), a chemically synthesized form of APF. Biochemical analysis revealed that as-APF increased p53 levels in two ways: by decreasing ubiquitin specific protease 2a (USP2a) expression leading to enhanced ubiquitination of murine double minute 2 E3 ubiquitin ligase (MDM2), and by suppressing association of p53 with MDM2, thus impairing p53 ubiquitination. Biological responses to as-APF were suppressed by increased expression of wild type, but not mutant USP2a, which enhanced cell growth via upregulation of a cell cycle mediator, cyclin D1, at both transcription and protein levels. Consistent with this, gene silencing of USP2a with siRNA arrested cell proliferation. Our findings suggest that APF upregulates cellular p53 levels via functional attenuation of the USP2a-MDM2 pathway, resulting in p53 accumulation and growth arrest. These data also imply that targeting USP2a, MDM2, p53 and/or complex formation by these molecules may be relevant in the development of novel therapeutic approaches to IC/PBS

A 490 GHz planar circuit balanced Nb-Al2_\mathbf{2}O3_{\mathbf{3}}-Nb quasiparticle mixer for radio astronomy: Application to quantitative local oscillator noise determination

This article presents a heterodyne experiment which uses a 380-520 GHz planar circuit balanced Nb-$\mathrm{Al_2O_3}$-Nb superconductor-insulator-superconductor (SIS) quasiparticle mixer with 4-8 GHz instantaneous intermediate frequency (IF) bandwidth to quantitatively determine local oscillator (LO) noise. A balanced mixer is a unique tool to separate noise at the mixer's LO port from other noise sources. This is not possible in single-ended mixers. The antisymmetric IV characteristic of a SIS mixer further helps to simplify the measurements. The double-sideband receiver sensitivity of the balanced mixer is 2-4 times the quantum noise limit $h\nu/k_B$ over the measured frequencies with a maximum LO noise rejection of 15 dB. This work presents independent measurements with three different LO sources that produce the reference frequency but also an amount of near-carrier noise power which is quantified in the experiment as a function of the LO and IF frequency in terms of an equivalent noise temperature $T_{LO}$. In a second experiment we use only one of two SIS mixers of the balanced mixer chip, in order to verify the influence of near-carrier LO noise power on a single-ended heterodyne mixer measurement. We find an IF frequency dependence of near-carrier LO noise power. The frequency-resolved IF noise temperature slope is flat or slightly negative for the single-ended mixer. This is in contrast to the IF slope of the balanced mixer itself which is positive due to the expected IF roll-off of the mixer. This indicates a higher noise level closer to the LO's carrier frequency. Our findings imply that near-carrier LO noise has the largest impact on the sensitivity of a receiver system which uses mixers with a low IF band, for example superconducting hot-electron bolometer (HEB) mixers.Comment: 13 pages, 8 figures, 2 tables, see manuscript for complete abstrac

Modularity and community detection in bipartite networks

The modularity of a network quantifies the extent, relative to a null model network, to which vertices cluster into community groups. We define a null model appropriate for bipartite networks, and use it to define a bipartite modularity. The bipartite modularity is presented in terms of a modularity matrix B; some key properties of the eigenspectrum of B are identified and used to describe an algorithm for identifying modules in bipartite networks. The algorithm is based on the idea that the modules in the two parts of the network are dependent, with each part mutually being used to induce the vertices for the other part into the modules. We apply the algorithm to real-world network data, showing that the algorithm successfully identifies the modular structure of bipartite networks.Comment: RevTex 4, 11 pages, 3 figures, 1 table; modest extensions to conten

Phase-based video motion processing

We introduce a technique to manipulate small movements in videos based on an analysis of motion in complex-valued image pyramids. Phase variations of the coefficients of a complex-valued steerable pyramid over time correspond to motion, and can be temporally processed and amplified to reveal imperceptible motions, or attenuated to remove distracting changes. This processing does not involve the computation of optical flow, and in comparison to the previous Eulerian Video Magnification method it supports larger amplification factors and is significantly less sensitive to noise. These improved capabilities broaden the set of applications for motion processing in videos. We demonstrate the advantages of this approach on synthetic and natural video sequences, and explore applications in scientific analysis, visualization and video enhancement.Shell ResearchUnited States. Defense Advanced Research Projects Agency. Soldier Centric Imaging via Computational CamerasNational Science Foundation (U.S.) (CGV-1111415)Cognex CorporationMicrosoft Research (PhD Fellowship)American Society for Engineering Education. National Defense Science and Engineering Graduate Fellowshi

Research Reports: 1988 NASA/ASEE Summer Faculty Fellowship Program

The basic objectives are to further the professional knowledge of qualified engineering and science faculty members; to stimulate an exchange of ideas between participants and NASA: to enrich and refresh the research and teaching activities of the participants' institutions; and to contribute to the research objectives of the NASA centers. Topics addressed include: cryogenics; thunderstorm simulation; computer techniques; computer assisted instruction; system analysis weather forecasting; rocket engine design; crystal growth; control systems design; turbine pumps for the Space Shuttle Main engine; electron mobility; heat transfer predictions; rotor dynamics; mathematical models; computational fluid dynamics; and structural analysis

Globular Cluster and Galaxy Formation: M31, the Milky Way and Implications for Globular Cluster Systems of Spiral Galaxies

The globular cluster (GC) systems of the Milky Way and of our neighboring spiral galaxy, M31, comprise 2 distinct entities, differing in 3 respects. 1. M31 has young GCs, ages from ~100 Myr to 5 Gyr old, as well as old globular clusters. No such young GCs are known in the Milky Way. 2. We confirm that the oldest M31 GCs have much higher nitrogen abundances than do Galactic GCs at equivalent metallicities. 3. Morrison et al. found M31 has a subcomponent of GCs that follow closely the disk rotation curve of M31. Such a GC system in our own Galaxy has yet to be found. These data are interpreted in terms of the hierarchical-clustering-merging (HCM) paradigm for galaxy formation. We infer that M31 has absorbed more of its dwarf systems than has the Milky Way. This inference has 3 implications: 1. All spiral galaxies likely differ in their GC properties, depending on how many companions each galaxy has, and when the parent galaxy absorbs them. The the Milky Way ties down one end of this spectrum, as almost all of its GCs were absorbed 10-12 Gyr ago. 2. It suggests that young GCs are preferentially formed in the dwarf companions of parent galaxies, and then absorbed by the parent galaxy during mergers. 3. Young GCs seen in tidally-interacting galaxies might come from dwarf companions of these galaxies, rather than be made a-new in the tidal interaction. There is no ready explanation for the marked difference in nitrogen abundance for old M31 GCs relative to the oldest Galactic GCs. The predictions made by Li & Burstein regarding the origin of nitrogen abundance in globular clusters are consistent with what is found for the old M31 GCs compared to that for the two 5 Gyr-old M31 GCs.Comment: to be published in ApJ, Oct 2004; 13 pages of text, 2 tables, 7 postscript figure

Next nearest neighbour Ising models on random graphs

This paper develops results for the next nearest neighbour Ising model on random graphs. Besides being an essential ingredient in classic models for frustrated systems, second neighbour interactions interactions arise naturally in several applications such as the colour diversity problem and graphical games. We demonstrate ensembles of random graphs, including regular connectivity graphs, that have a periodic variation of free energy, with either the ratio of nearest to next nearest couplings, or the mean number of nearest neighbours. When the coupling ratio is integer paramagnetic phases can be found at zero temperature. This is shown to be related to the locked or unlocked nature of the interactions. For anti-ferromagnetic couplings, spin glass phases are demonstrated at low temperature. The interaction structure is formulated as a factor graph, the solution on a tree is developed. The replica symmetric and energetic one-step replica symmetry breaking solution is developed using the cavity method. We calculate within these frameworks the phase diagram and demonstrate the existence of dynamical transitions at zero temperature for cases of anti-ferromagnetic coupling on regular and inhomogeneous random graphs.Comment: 55 pages, 15 figures, version 2 with minor revisions, to be published J. Stat. Mec

Electronic band structure and carrier effective mass in calcium aluminates

First-principles electronic band structure investigations of five compounds of the CaO-Al2O3 family, 3CaO.Al2O3, 12CaO.7Al2O3, CaO.Al2O3, CaO.2Al2O3 and CaO.6Al2O3, as well as CaO and alpha-, theta- and kappa-Al2O3 are performed. We find that the conduction band in the complex oxides is formed from the oxygen antibonding p-states and, although the band gap in Al2O3 is almost twice larger than in CaO, the s-states of both cations. Such a hybrid nature of the conduction band leads to isotropic electron effective masses which are nearly the same for all compounds investigated. This insensitivity of the effective mass to variations in the composition and structure suggests that upon a proper degenerate doping, both amorphous and crystalline phases of the materials will possess mobile extra electrons