Digital Commons Network^™

Constraints On The Origin Of The Remarkable Lithium Abundance In The Halo Star Bd+23 3912, Jeremy R. King, Constantine P. Deliyannis, Ann Merchant Boesgaard

Publications

The Li abundance of the halo star BD+23 3912 ([Fe/H]=-1.5) lies a factor of 2 - 3 above the Spite plateau. This remarkable difference could reflect either less-than-average stellar Li depletion from a higher primordial Li abundance (as predicted by the Yale rotational stellar evolutionary models), which may have interesting implications for Big Bang nucleosynthesis, or the extraordinary action of Galactic Li production mechanisms. It is also possible that both processes have acted. We use our high resolution, high S/N Keck HIRES spectrum of BD+23 3912 to determine the s-process element abundances and 6Li/7Li ratio in this star. These values …

Stellar Oxygen Abundances.V.Abundances Of Two Hyades Dwarfs Derived From The 6300 Angstroms [Oi] Line, Jeremy R. King, Daniel D. Hiltgen

Publications

We present observations of the 6300 Å [O I] spectral region in two cool Hyades dwarfs, vB 79 and vB 25. We derive a mean iron abundance, [Fe/H]˜+0.11, in good agreement with recent analyses of F and G Hyades dwarfs. The O abundance derived from spectrum synthesis, [O/H]˜+0.15, is between the values deduced by Garcia Lopez et al. (1993, ApJ, 412, 173; [O/H]=-0.05 to -0.10) and King (1993, Ph. D. Dissertation, University of Hawaii; [O/H]=+0.26), who employed the 7774 Å O I triplet in hotter Hyades dwarfs. An accounting of differences between these two 7774 Å analyses is given. Our …

Galactic Evolution Of Silicon Isotopes: Applications To Presolar Sic Grains From Meteorites, F X. Timmes, Donald D. Clayton

Publications

We calculate and discuss the chemical evolution of the isotopic silicon abundances in the interstellar medium (ISM) at distances and times appropriate to the birth of the solar system. This has several objectives, some of which are related to anomalous silicon isotope ratios within presolar grains extracted from meteorites; namely: (1) What is the relative importance for silicon isotopic compositions in the bulk ISM of Type II supernovae, Type Ia supernovae, and AGB stars? (2) Are 29Si and 30Si primary or secondary nucleosynthesis products? (3) In what isotopic direction in a three-isotope plot do core-collapse supernovae of different mass move …

Implementing The Public Welfare Requirement In New Mexico's Water Code, Consuelo Bokum

Publications

Despite the fact that the New Mexico legislature added a public welfare criterion to the water code over 10 years ago, the State Engineer Office has not addressed the application of the criterion by regulation and has only addressed the public welfare briefly in a few decisions. There is almost no case law in New Mexico addressing this issue. More and more participants, however, are raising public welfare in water rights protests. This paper addresses how the public welfare criterion has developed in western water law and proposes an approach for use of the criterion in New Mexico.

A Role For A Rab4-Like Gtpase In Endocytosis And In Regulation Of Contractile Vacuole Structure And Function In Dictyostelium Discoideum, John Bush, Lesly A. Temesvari, Juan Rodriguez-Paris, Greg Buczynski, James Cardelli

Publications

The small Mr Rab4-like GTPase, RabD, localizes to the endosomal pathway and the contractile vacuole membrane system in Dictyostelium discoideum. Stably transformed cell lines overexpressing a dominant negative functioning RabD internalized fluid phase marker at 50% of the rate of wild-type cells. Mutant cells were also slower at recycling internalized fluid. Microscopic and biochemical approaches indicated that the transport of fluid to large postlysosome vacuoles was delayed in mutant cells, resulting in an accumulation in acidic smaller vesicles, probably lysosomes. Also, RabD N121I-expressing cell lines missorted a small but significant percentage of newly synthesized lysosomal alpha-mannosidase precursor polypeptides. However, the …

The 9be Abundances Of Alpha Centauri A And B And The Sun: Implications For Stellar Evolution And Mixing, Jeremy R. King, Constantine P. Deliyannis, Ann Merchant Boesgaard

Publications

We present high-resolution, high signal-to-noise ratio spectra, obtained at the Cerro Tololo Inter-American Observatory 4 m telescope, of the Be II 3131 Å region in the metal-rich solar analog α Centauri A and its companion α Centauri B. Be abundances are derived relative to the Sun in a consistent fashion via spectrum synthesis. For α Cen A, we find [Be/H] = +0.20 ± 0.15, where the error reflects random uncertainties at the 1 σ confidence level; systematic errors of ~0.1 dex are also possible. The analysis of α Cen B is more uncertain since inadequacies in the line list, which …

Omaha's Public Libraries, Center For Public Affairs Research (Cpar)

Publications

The Omaha Public Library began as a subscription library in 1872. The "library" was located in a rented room on 14th Street between Douglas and Dodge with a collection of 2,600 donated books. The Library Association charged an annual fee of $3.00 for membership. In 1877 the State Legislature approved an act allowing the establishment of "free public libraries and reading rooms." That same year the Omaha City Council established the Omaha Public Library at the urging of the Omaha Library Association. The Library opened with a budget of$1,274.80, a librarian, and nine appointed directors, the precursor of the Library …

The Double Infared Source Toward The Soft Gamma-Ray Repeater Sgr 1900+14, F. J. Vrba, C. B. Luginbuhl, K. C. Hurley, P. Li, S. R. Kulkarni, M. H. Van Kerkwuk, Dieter H. Hartmann, L. E. Campusano, M. J. Graham, R. G. Clowes

Publications

We report the results of an extensive set of optical and near-infrared photometry and spectroscopy of the double infrared source reported by Hartmann et al. (1995) as a potential counterpart for the Galatic soft gamma-ray repeater SGR 1900 + 14. These objects are found to be variable but otherwise normal M5 supergiant stars at a distance of ~ 12-15 kpc and extinguised by Av ~ 19.2 mag, primarily by the general interstellar medium. We argue that the supergiants are likely gravitationally bround. These stars are positionally coincident with both quiescent X-ray and IRAS sources, suggestive of a yet-undetected third component …

The Angular Power Spectrum Of Batse 3b Gamma-Ray Bursts, Max Tegmark, Dieter H. Hartmann, Michael S. Briggs, Charles A. Meegan

Publications

We compute the angular power spectrum C1 from the BATSE 3B catalog of 1122 gamma-ray burts and find no evidence of clustering on any scale. These constraints bridge the entire range from samall scales (which probe source clustering and burst repetition) to the largest scales (which constrain possible anisotropies from the Galactic hal or from nearby cosmological large-scale structures). We develop an analysis tecnique that takes the angular position errors into account. For specific clustering or repetition models, strong upper limits can be obtained down to scales l ~ 30, corresponding to abou couple of degrees on the sky. The …

The Gamma-Ray Burst Rate At High Photon Energies, Karl Mannheim, Dieter H. Hartmann, Burkhardt Funk

Publications

Some gamma-ray burst (GRB) spectra exhibit high energy tails with the highest photon energy detected at 18 GeV. The spectral slope of the high-energy tails is suffieniently flat in vF, to consider the possibility of their dectection at still higher energies. We calculate how many bursts can resonably be expected above a given energy threshold for a cosmological distribution of bursts satisfying the observed apparent birghtness distribution. The crucial point is that the gamma-ray absorption by pair production in the intergalactic diffuse radiation field climinates burts from beyond the gamma-ray horizion, thus drastically reducing the number of bursts at high …

Prepayment Pitfalls, Roger Bernhardt

Publications

This article discusses prepayment dangers in California.

Overview Of Results From 1994 & 1995 School-Based Decision Making Surveys, Jane Clark Lindle, Bruce S. Gale, Brenda Curry-White

Publications

The 1994 and 1995 School-Based Decision Making (SBDM) Surveys were conducted in the fall of each of those years for the Study of Education Policy. This report compares the 1994 and 1995 responses to three questions: (1) What do people think of the effectiveness of SBDM? (2) Who is involved in the SBDM decisions? and (3) What are councils doing? The discussion focuses on school and district effectiveness, the barriers to SBDM, SBDM trainers' network, parent involvement, efforts to involve minorities and women, council productivity, improvement strategies, and the budget process. Findings show that most people rate SBDM as good …

The Metallicity Dependence Of The Stellar Luminosity And Initial Mass Functions: Hst Observations Of Open And Globular Clusters, Ted Von Hippel, Gerard Gilmore, Nial R. Tanvir, David Robinson, Derek H.P. Jones

Publications

Using HST and the WFPC2 we have acquired very deep V- and I-band photometry of stars in NGC 2420 and NGC 2477 to study cluster luminosity functions at approximately solar metallicity. We have determined these cluster luminosity functions down to MI = 10.5 (0.2 M⊙) and find that the luminosity function of NGC 2420 turns over at MI ≈ 9.0, and possibly stops altogether by MI ≈ 9.5. The luminosity function of NGC 2477 may flatten at MI ≥ 9.5. We compare our open cluster luminosity functions to the solar neighborhood field star luminosity function of Kroupa, Tout \& Gilmore …

The Production Of 44ti And 60co In Supernovae, F. X. Timmes, S. E. Woosley, Dieter H. Hartmann, R. D. Hoffman

Publications

The production of the radioactive isotopes 44Ti and 60Co in all types of supernovae is examined and compared to observational constraints inculding Galactic gamma-ray surveys, measurements of the diffuse 511 keV radiation, gamma-ray observations of Cas A, the late-time light curve of SN 1987A, and isotopic anomalies found in silicon carbide grains in meteorities. The (revished) line flux from 44Ti decay in the Cas A supernova remnant reported by COMPTEL on the Compton Gamma Ray Observatory is near the upper bound expected from our models. The necessary concurrent ejection of 56Ni would also imply that Cas A was a brighter …

Involvement Of The Vacuolar Proton-Translocating Atpase In Multiple Steps Of The Endo-Lysosomal System And In The Contractile Vacuole System Of Dictyostelium Discoideum, Lesly A. Temesvari, Juan M. Rodriguez-Paris, John M. Bush, Linyi Zhang, James A. Cardelli

Publications

We have investigated the effects of Concanamycin A (CMA), a specific inhibitor of vacuolar type H(+)-ATPases, on acidification and function of the endo-lysosomal and contractile vacuole (CV) systems of D. discoideum. This drug inhibited acidification and increased the pH of endo-lysosomal vesicles both in vivo and in vitro in a dose dependent manner. Treatment also inhibited endocytosis and exocytosis of fluid phase, and phagocytosis of latex beads. This report also confirms our previous conclusions (Cardelli et al. (1989) J. Biol. Chem. 264, 3454–3463) that maintenance of acidic pH in lumenal compartments is required for efficient processing and targeting of a …

A Possible X-Ray Counterpart To Sgr 1900+14, K. Hurley, P. Li, F. Vrba, C. Luginbuhl, Dieter H. Hartmann, C. Kouvelioutou, C. Meegan, G. Fishman, S. Kulkarni, D. Frail

Publications

The location of the soft gamma repeater SGR 1900ϩ14 was recently reduced to two 15 arcmin2 alternate error boxes by the network synthesis method. We have used the ROSAT High Resolution Imager to observe the error box that is closest to the supernova remnant G42.8ϩ0.6. A quiescent, steady, point X-ray source was found at ␣(2000) ϭ 19h07m14!15, ␦(2000) ϭ 9Њ19Ј19"06, whose unabsorbed flux is 3 ϫ 10Ϫ12 ergs cmϪ2 sϪ1. Its position is also consistent with a peculiar double infrared source described in a companion paper. We have also examined this region using the VLA,1 and have obtained upper limits …

48ca Production In Matter Expanding From High Temperature And Density, B S. Meyer, Tracy D. Krishnan, Donald D. Clayton

Publications

We calculate with a large nuclear reaction network the nuclear dynamics associated with the expansions and cooling of initially hot and dense matter. We study matter with neutron excess near that of 48Ca, because one objective is to clarify the nucleosynthesis of that abundant neutron-rich nucleus, whose origin has been enigmatic. Expecting that supernovae provide the site of its origin, we take initial temperatures near T9 = 10 but survey a wide range of initial densities, corresponding to a wide range in initial entropies. The highest entropies are probably associated with winds from newborn neutron stars in Type II collapse …

Wisdom Across The Atlantic: North America And The European Experience, Paul S. Kibel

Publications

No abstract provided.

The Wisdom Of Teacher Involvement In School-Linked Social Services, Jane Clark Lindle

Publications

Recently, school-linked services phenomena have been examined through various implementation strategies. Most discussions are divided over issues such as points of deliver, institutional or agency territoriality, as well as financing and payment schemes. This debate focuses on the less well examined concern over the role of classroom teachers in school-linked service delivery.

Food Dispersion And Foraging Energetics: A Mechanistic Synthesis For Field Studies Of Avian Benthivores, James R. Lovvorn, Michael P. Gillingham

Publications

Much effort has focused on modeling and measuring the energy costs of free existence and the foraging strategies of animals. However, few studies have quantitatively linked these approaches to the patch structure of foods in the field. We developed an individual—based model that relates field measurements of the dispersion of benthic foods to search costs and foraging profitability of diving ducks. On Lake Mattamuskeet, North Carolina, Canvasback ducks (Aythya valisineria) eat only the belowground winter buds of the submerged plant Vallisneria americana. We measured and modeled the patch structure of winter buds at the level of potential …

Examination Of The Endosomal And Lysosomal Pathways In Dictyostelium Discoideum Myosin I Mutants, Lesly A. Temesvari, John M. Bush, Michelle D. Peterson, Kristine D. Novak, Margaret A. Titus, James A. Cardelli

Publications

The role of myosin Is in endosomal trafficking and the lysosomal system was investigated in a Dictyostelium discoideum myosin I double mutant myoB-/C-, that has been previously shown to exhibit defects in fluid-phase endocytosis during growth in suspension culture (Novak et al., 1995). Various properties of the endosomal pathway in the myoB-/C- double mutant as well as in the myoB- and myoC- single mutants, including intravesicular pH, and intracellular retention time and exocytosis of a fluid phase marker, were found to be indistinguishable from wild-type parental cells. The intimate connection between the contractile vacuole complex and the endocytic pathway in …

Main Sequence Masses And Radii From Gravitational Redshifts, Ted Von Hippel

Publications

Modern instrumentation makes it possible to measure the mass to radius ratio for main sequence stars in open clusters from gravitational redshifts. For stars where independent information is available for either the mass or the radius, this application of general relativity directly determines the other quantity. Applicable examples are: 1) measuring the radii of solar metallicity main sequence stars for which the mass - luminosity relation is well known, 2) measuring the radii for stars where model atmospheres can be used to determine the surface gravity (the mass to radius squared ratio), 3) refining the mass - radius relation for …

Book Review, Lakshman D. Guruswamy

Publications

No abstract provided.

Justice For The Sea Turtle: Marine Conservation And The Court Of International Trade, Paul S. Kibel

Publications

On April 10, 1996, the United States Court of International Trade (CIT) issued a landmark decision in Earth Island Institute v. Christopher. In this case, the CIT ordered the U.S. State, Commerce, and Treasury Departments to block the importation of shrimp from all nations that had not adopted adequate policies to protect sea turtles. Worldwide, over one hundred thousand sea turtles are killed each year as a result of shrimp-harvesting operations: the turtles drown trying to escape the shrimp nets. The CIT based its ruling on an interpretation of a 1989 amendment to the federal Endangered Species Act (ESA), § …

Reconstructing The Marketplace: The International Timber Trade And Forest Protection, Paul S. Kibel

Publications

This Article proposes a new international regime to help recapture the lost value of native forests and promote global forest protection - the General Agreement on the Timber Trade.

Part I outlines the essential differences between native forest conservation and industrial forestry. Part II chronicles the ecological, social, and economic losses resulting from the destruction of native forests. Part Ill reveals the national and international components of the timber trade, and demonstrates how these components contribute to unsustainable logging practices. Part IV assesses the effectiveness of prior and ongoing international efforts to reform the global timber trade and promote sustainable …

Legal Developments In The First Half Of The United Nations Decade Of International Law, Sompong Sucharitkul

Publications

The time has come for us in the Northwest region, as well as in the larger Asian Pacific region, to take stock of the progress made up to this point in the various activities and undertakings of States and International Organizations including Non-Governmental Organizations as part and parcel of the world community. It is not the purpose of this brief report to give a detailed comprehensive and analytical survey of all the achievements, of all the activities in progress and the failures and disappointments that we as members of the international community have encountered over the past five years. That …

Through The Looking Glass: Recent Developments In Affirmative Action, Kathleen Morris

Publications

The year 1995 saw three major developments that threaten the future of voluntary affirmative action programs in California and nationwide. On June 12, the U.S. Supreme Court in Adarand Constructors, Inc. v. Pena, held that voluntary federal affirmative action programs should be subject to the same "strict scrutiny" reserved for all other racial classifications. The following month, the Regents of the University of California voted to abolish the use of race and gender as factors in admissions and hiring in the University of California system. Finally, last year the so-called "California Civil Rights Initiative" ("CCRI") was presented to the …

An Argument For Universal Pediatric Hiv Testing, Counseling And Treatment, Colin Crawford

Publications

This symposium was called to address constitutional concerns raised by the controversy over the issue of mandatory pediatric testing, counseling and treatment for the human immuno-deficiency virus (HIV). In due course, I will turn to those concerns,' and explain my view that the need to test and treat newborns for HIV constitutes a medical emergency that overrides the most serious constitutional concerns. However, before doing so, it is helpful to put the debate in perspective, to explain what, in ABC's view, the controversy is really all about, and to indicate why our organization has so strenuously advocated mandatory pediatric HIV …

Analyzing Evidence Of Environmental Justice: A Suggestion For Professor Been, Colin Crawford

Publications

One effect of the environmental justice movement has been to draw attention to the prejudices inherent in some modem environmental policies. These prejudices are most apparent when analyzing the location of hazardous waste facilities throughout the country. Several recent environmental justice studies have debated whether the location of these facilities has a direct correlation to the percentage of minorities in the surrounding areas.

This article critiques some of the methodology of these recent studies, most notably that of Professor Vicki Been, to determine the rationale governing the placement of hazardous waste facilities. Furthermore, this article suggests that researchers should expand …

Changing Positions And Entrenched Polemics: A Brief History Of The Association To Benefit Children's Views On Pediatric Hiv Testing, Counseling, And Care, Colin Crawford

Publications

In my remarks today, I intend to do three things. First, I want to document the trajectory of the Association to Benefit Children's (ABC) approach to this issue, which was considerably more layered and nuanced than often characterized by the press and, certainly, by our most virulent opponents. Second, I aim to offer some reflections as to why the debate became as acrimonious as it did, and how that impeded resolution of this issue satisfactory to the widest possible number of people. Third, I hope that these reflections will provide a basis for some suggestions as to how future debate …