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Do Gamma-Ray Bursts Originate From An Extended Galactic Halo Of High-Velocity Neutron Stars?, Dieter H. Hartmann, Lawrence E. Brown, Lih-Sin The, Eric V. Linder, Vahé Petrosian, George R. Blumenthal, Kevin C. Hurley

Publications

The γ-ray burst brightness distribution in inhomogeneous and the distribution on the sky is nearly isotropic. These features argue against an association with γ-ray bursts with those Galactic objects that are known to exhibit a strong concentration toward the Galactic center or plane. The observed statistical properties indicate a cosmological origin. Circumstantial evidence suggests that neutron stars are involved in the burst phenomenon. HEre we consdier Population II neutron stars in an extended Galatic Halo (EGH) as an alternative to cosmological scenaries. The BATSE data indicate a small deviation from isotropy near the 2 σ level of statistical significance. If …

Smm Observations Of Gamma-Ray Transients. 2: A Search For Gamma-Ray Lines Between 400 And 600 Kev From The Crab Nebula, Michael J. Harris, Gerald H. Share, Mark D. Leising

Publications

We have search spectra obtained by the Solar Maximum Mission Gamma-Ray Spectrometer during 1981-1988 for evidence of transient gamma-ray lines from the Crab Nebula which have been reported by previous experiments at energies 400-460 keV and 539 keV. We find no evidence for significant emission in any of these lines on time scales between aproximately 1 day and approximately 1 yr. Our 3 sigma upper limits on the transient flux during 1 d intervals are approximately equal to 2.2 x 10-3 photons/sq cm/s for narrow lines at any energy, and approximately equal to 2.9 x 10-3 photons/sq cm/s for the …

Proliferating Dendritic Cell Progenitors In Human Blood, Nikolaus Romani, Stefan Gruner, Daniela Brang

Publications

CD34⁺cells in human cord blood and marrow are known to give rise to dendritic cells (DC), as well as to other myeloid lineages. CD34⁺cells are rare in adult blood, however, making it difficult to use CD34 + ceils to ascertain if DC progenitors are present in the circulation and if blood can be a starting point to obtain large numbers of these immunostimulatory antigenpresenting cells for clinical studies. A systematic search for DC progenitors was therefore carried out in several contexts. In each case, we looked initially for the distinctive proliferating aggregates that were described previously …

Influenza Virus-Infected Dendritic Cells Stimulate Strong Proliferative And Cytolytic Responses From Human Cd8+ T Cells, Nina Bhardwaj, Armin Bender, Noemi Gonzalez

Publications

Antigen-specific, CD8+, cytolytic T lymphocytes (CTLs) could potentially provide resistance to several infectious and malignant diseases. However, the cellular requirements for the generation of specific CTLs in human lymphocyte cultures are not well defined, and repetitive stimulation with antigen is often required. We find that strong CD8+ CTL responses to influenza virus can be generated from freshly isolated blood T cells, as long as dendritic cells are used as antigen presenting cells (APCs). Small numbers of dendritic cells (APC:T cell ratio of 1:50-1:100) induce these CTL responses from most donors in 7 d of culture, but monocytes are weak or …

The Tissue Distribution Of The B7-2 Costimulator In Mice: Abundant Expression On Dendritic Cells In Situ And During Maturation In Vitro, Kayo Inaba, Margit D. Witmer-Pack, Muneo M. Inaba

Publications

B7-2 is a recently discovered, second ligand for the CTLA-4/CD28, T cell signaling system. Using the GL-1 rat monoclonal antibody (mAb), we monitored expression of B7-2 on mouse leukocytes with an emphasis on dendritic cells. By cytofluorography, little or no B7-2 was detected on most cell types isolated from spleen, thymus, peritoneal cavity, skin, marrow, and blood. However, expression of B7-2 could be upregulated in culture. In the case of epidermal and spleen dendritic cells, which become highly immunostimulatory for T cells during a short period of culture, the upregulation of B7-2 was dramatic and did not require added stimuli. …

Zanvil Alexander Cohn 1926-1993, Ralph M. Steinman, Carol L. Moberg

Publications

Zanvil Alexander Cohn, an editor of this Journal since 1973, died suddenly on June 28, 1993. Cohn is best known as the father of the current era of macrophage biology. Many of his scientific accomplishments are recounted here, beginning with seminal studies on the granules of phagocytes that were performed with his close colleague and former editor of thisJournaI, James Hirsch. Cohn and Hirsch identified the granules as lysosomes that discharged their contents of digestive enzymes into vacuoles containing phagocytosed microbes. These findings were part of the formative era of cell biology and initiated the modern study of endocytosis and …

Property Taxes, School Equalization And Business Location In South Carolina, 1994, Holley Hewitt Ulbrich

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No abstract provided.

Journal Of The Community Development Society Vol. 25, No. 02, Center For Public Affairs Research (Cpar)

Publications

For more than twenty-five years, the journal of the Community Development Society has disseminated information on the theory, research, and practice of community development. Biannual publications have contained the most relevant materials that add to our knowledge of community development. While much of the material in the Journal articles has been derived from generally accepted principles, concepts, or practices of community development, from time to time a few of the articles may have attempted to dramatically extend current thinking. We learn by challenging what has been accepted. For generations the social sciences have advanced using some modification of this learning …

Journal Of The Community Development Society Vol. 25, No. 01, Center For Public Affairs Research (Cpar)

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25th Anniversary Issue: What We Have Learned

Thinking Like A Lawyer, Emily Calhoun

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No abstract provided.

The Forgotten Link: Control In Section 482, Wayne M. Gazur

Publications

The foundation of international taxable income allocations between related parties is formed by the imposition of an arm's length standard. The presence of "control" over a person invokes this measure. The author examines the implications of control presented by continuing developments in the global business environment, including the rise of cooperative interfirm arrangements.

Values, Pierre Schlag

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No abstract provided.

A Case Of Clothing And Smell Obsession In A Bisexual Adult Woman, Marianne Wesson

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No abstract provided.

Intersubject Variability Of Real-Ear Sound Pressure Level: Conventional And Insert Earphones, Michael Valente, Lisa G. Potts, L. Maureen Valente, William Vass, Joel Goebel

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No abstract provided.

Eastern Airlines: The Rise And Fall Of "The Wings Of Man", Benjamin H. Troemel Jr., James T. Schultz, Marian C. Schultz

Publications

This paper examines the rise and fall of Eastern Airlines from 1928 to 1991. lt outlines the carrier's development under a succession of leaders and discusses the major events of each leader's reign. From a small contract mail carrier known as Pitcairn Aviation, Eastern grew to become one of the largest airlines in the free world. But after 26 years of growth and prosperity under the leadership of Eddie Rickenbacker, the airline began to stumble in the early 1960s. Frank Lorenzo took the reins in 1986 and began selling the carrier's assets while attempting to destroy the unions. After a …

Chaos And The Law Of Borrowed Servant: An Argument For Consistency, J. Dennis Hynes

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No abstract provided.

Voice In Government: The People, Emily Calhoun

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No abstract provided.

The Untermensch As Ubermensch, Paul Campos

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No abstract provided.

The Effects Of Temperature And Daylength On The Rosa Polyphenism In The Buckeye Butterfly, Precis Coenia (Lepidoptera: Nymphalidae), Kelly C. Smith

Publications

In North Carolina, Precis coenia that emerge during the Summer months exhibit a ventral hindwing (VHW) with well-defined reddish-brown and brown pattern elements on a light tan background. During late Summer and early Fall, however, individuals begin to appear with poorly defined or obscured pattern elements on a dark reddish-brown background. The present study shows that the Fall (rosa) color morph can be induced by either low rearing temperatures or short daylengths. The effect of such conditions seems to be cumulative throughout the larval life, although animals are much more sensitive during the last 24 hours of larval …

Behavioral Effects Of Tyrosine During Sustained Wakefulness, D. L. Wiegmann, D. F. Neri, R. R. Stanny, S. A. Shappell, A. H. Mccardie, D. L. Mckay

Publications

The fatigue and cognitive performance deficits associated with sleep loss and stress, like that experienced during sustained flight operations and nighttime flying, have motivated the search for effective nonpharmacological countermeasures. The behavioral effects of the potential countermeasure tyrosine, an amino-acid precursor to dopamine and norepinephrine, were examined during an episode of continuous nighttime work involving one night's sleep loss. Volunteers performed nine iterations of a battery of cognitive and subjective tasks for approximately 13 h, beginning at 1930 and ending at 0820 the following morning. Subjects remained awake throughout the day on which the experiment began and were awake for …

On 26al And Other Short-Lived Interstellar Radioactivity, Dieter H. Hartmann, Donald D. Clayton, Mark D. Leising

Publications

Several authors have shown that massive stars exploding at a rate of about three per century can account for a large portion, if not all, of the observed interstellar 26Al. In a separate argument using models of Galatic chemical evolution, Clayton (1984) showed that the 26Al/27Al production ratio was not large enough to maintain enought 26Al in the Galactic disk gas of ~ 10^10 M⊙ having solar composition. We present a resolution of those conflicting arguments. A past history of Galactic infall growing the Galatic disk so dilutes the stable 27Al concentration that the two approaches can be brought into …

On Al-26 And Other Short-Lived Interstellar Radioactivity, Mark D. Leising, Donald D. Clayton, Dieter H. Hartmann

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Several authors have shown that massive stars exploding at a rate of about three per century can account for a large portion, if not all, of the observed interstellar Al-26. In a separate argument using models of Galactic chemical evolution, Clayton (1984) showed that the Al-26/Al-27 production ratio was not large enough to maintain enough Al-26 in the Galactic disk gas of about 10 exp 10 solar masses having solar composition. We present a resolution of those conflicting arguments. A past history of Galactic infall growing the Galactic disk so dilutes the stable Al-27 concentration that the two approaches can …

Gamma-Ray Constraints On Supernova Nucleosynthesis, Mark D. Leising

Publications

Gamma-ray spectroscopy holds great promise for probing nucleosynthesis in individual supernova explosions via short-lived radioactivity, and for measuring current global Galactic supernova nucleosynthesis with longer-lived radioactivity. It was somewhat surprising that the former case was realized first for a Type II supernova, when both Co-56 and Co-57 were detected in SN 1987A. These provide unprecedented constraints on models of Type II explosions and nucleosynthesis. Live Al-26 in the Galaxy might come from Type II supernovae, and if it is eventually shown to be so, can constrain massive star evolution, supernova nucleosynthesis, and the Galactic Type II supernova rate. Type Ia …

Inhomogenous Chemical Evolution Of The Galactic Disk, Donald D. Clayton, Guy Malinie, Dieter H. Hartmann, Grant J. Mathews

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No abstract provided.

Gravity Wave-Driven Fluctuations In The O2 Atmospheric (0-1) Nightglow From An Extended, Dissipative Emission Region, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid

Publications

The wave-driven fluctuations in the O2(0-1) atmospheric nightglow is modeled and the parameter (eta) is calculated using a model that accounts for either three-body recombination of atomic oxygen atoms alone to form the O2(b exp 1 Sigma(g)(+)) state directly, or by the further inclusion of the process that allows the formation of the O2(c exp 1 Sigma(u)(-)) intermediate state. The calculations are performed for a latitude of 18 deg N and for the months of March and June. The general results, which display how (eta) varies with wave period, horizontal wavelength, season, and chemical scheme, show that for given values …

The Effects Of Luminance Boundaries On Color Perception, Richard E. Kronauer, Charles F. Stromeyer Iii, Alex Chaparro

Publications

The luminance and red-green chromatic detection mechanisms respond to, respectively, the sum and difference of the long-wave (L) and middle-wave (M) zone contrast signals. The most-detectable stimulus is not a small patch of luminance drifting grating, as suggested by others, but rather a small, foveal red-green chromatic flash. Even at the smallest test size examined, 2.3' diameter, the red-green mechanism i~s more sensitive than the luminance mechanism, which has profound implication for visual physiology. When a suprathreshold luminance flash (a pedestal) occurs coincidentally with a red-green chromatic flash, detection of color is facilitated ~2-fold, regardless of spot size, as shown …

An Alternative Representation Of The Ice Canopy For Calculating Microwave Brightness Temperatures Over A Thunderstorm, Bradley M. Muller, Henry E. Fuelberg, Eric A. Smith

Publications

Passive microwave brightness temperatures (T(B)'s) at 92 and 183 GHz from an aircraft thunderstorm overflight are compared with values calculated from radar-derived hydrometeor profiles and a modified proximity sounding. Two methods for modeling particles in the ice canopy are contrasted. The first is a ''traditional'' approach employing Marshall-Palmer ice spheres. The second, or ''alternative,'' method partitions 20% of the ice water content into a Marshall-Palmer component for graupel and hail, and 80% into a modified gamma spherical particle size distribution function representing ice crystals.

Results from the alternative approach are superior to those from the traditional method in the anvil …

Uaa Student Showcase Journal: Recognizing Excellence (Spring, 1993), N/A N/A

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No abstract provided.

Uaa Student Showcase Journal: Recognizing Excellence (Summer 1993), N/A N/A

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No abstract provided.

Smm Observations Of Gamma-Ray Transients. I. A Search For Variable Emission At Mev Energies From Five Galactic And Extragalactic Sources, Mark D. Leising, M J. Harris, G H. Share, J E. Grove

Publications

Transient emission at energies near 1 MeV has been reported by previous experiments on time scales of weeks to months from the Galactic center, the Crab Nebula, and Cyg X-1, and on shorter time-scales from NGC 4151 and Cen A. The spectra of these events fall into two broad classes: a broad line-like feature centered near 1 MeV, and continuum emission (or a very broad feature) extending from ˜600 keV up to several MeV. These features have been interpreted theoretically in terms of emission from hot pair-dominated plasmas, which may be the necessary positron source implied by reports of narrow …