Star formation and spiral structure in M81

High resolution digitized images of M81 in the radio continuum, H alpha, H I, and I band are used to see how well various density wave models agree in detail with observations. It was found that the observed width of the nonthermal radio arms favors a cloudy version of a density wave model. The radial distribution of the set of giant radio H II regions disagrees with the simple expression of Shu and Visser for star formation by a density wave. The observed displacements of the giant radio H II regions from the spiral velocity shock indicate that some revisions in the details of the ballistic particle model of Leisawitz and Bash are necessary

Sheared Interpolation and Gradient Estimation for Real-Time Volume Renderings

In this paper we present a technique for the interactive control and display of static and dynamic 3D datasets. We describe novel ways of tri-linear interpolation and gradient estimation for a real-time volume rendering system, using coherency between rays. We show simulation results that compare the proposed methods to traditional algorithms and present them in the context of Cube-3, a special-purpose architecture capable of rendering 5123 16-bit per voxel datasets at over 20 frames per second.Engineering and Applied Science

Towards a Scalable Architecture for Real-Time Volume Rendering

In this paper we present our research eff orts towards a scalable volume rendering architecture for the real-time visualization of dynamically changing high-resolution datasets. Using a linearly skewed memory interleaving we were able to develop a parallel data ow model that leads to local, fixed-bandwidth interconnections between processing elements. This parallel dataflow model diff ers from previous work in that it requires no global communication of data except at the pixel level. Using this data ow model we are developing Cube-4, an architecture that is scalable to very high performances and allows for modular and extensible hardware implementations.Engineering and Applied Science

Modeling the Electromagnetic Radiation from Electrically Small Table-Top Products

It is noted that the most difficult radiated electromagnetic interference (EMI) problems with table-top products often occur at frequencies where the maximum dimensions of the product are much smaller than a wavelength. Electrically small table-top products tend to be much more efficient radiation sources than dipole source models would predict, and the radiation is generally much more difficult to contain than other types of EMI source models indicated. The ways in which electrically small sources radiate are investigated, and a technique for modeling electrically small table-top products that have power or signal cables is proposed. The end-driven wire model is a strategy for reducing the product to a form that is more readily analyzed. The results is a relatively simple configuration that includes only those parameters of the product that are of primary importance to the radiated EMI calculation

Mickey Donohue

https://digitalcommons.library.umaine.edu/mmb-vp/4533/thumbnail.jp

Distinguishing Between Animates And Inanimates: Not By Motion Alone

Martin E. P. Seligman, professor of psychology at the University of Pennsylvania, is one of the world\u27s leading authorities on learned helplessness and its relation to optimism and hope. This collection brings together eminent psychologists and professionals whose work has been greatly influenced by Seligman\u27s innovative work

A Lung Cancer Screening Personalized Decision-aid Improves Knowledge and Reduces Decisional Conflict Among a Diverse Population of Smokers at an Urban Academic Medical Center

Introduction: Few lung cancer screening decision aids have been tested in diverse populations. The study objective was to determine whether the online decision aid www.shouldiscreen.com impacts knowledge of and decisional conflict around lung cancer screening in a diverse population. Methods: Eligible patients had significant smoking histories, were at increased risk for lung cancer (ages 45-80, \u3e20 pack-years, smoking within last 15 years) and had no history of prior lung cancer or screening. Data was collected and analyzed in 2017. Results: 40 patients were enrolled: 80% were female, 62.5% black, 33% white, and 48% had a high school education or less. 80% were current smokers with a mean of 34 pack-years accumulated. 35% were eligible for screening by U.S. Preventive Services Task Force criteria. After reviewing the decision aid, knowledge increased in all categories including risk factors for lung cancer (3.58 to 4.30, p\u3c0.01), benefits of screening (1.58 to 2.30, p\u3c0.01), possible harms of screening (0.93 to 2.08, p\u3c0.01), and eligibility for screening (2.10 to 2.65, p\u3c0.01). Decisional conflict was reduced from 21.25 to 8.65 (p\u3c0.01). After use of the decision aid, more patients expressed a preference not to be screened for lung cancer, such that concordance with USPSTF guidelines decreased among those who were eligible to screen increased among those who did not yet meet eligibility criteria; however, this finding was not statistically significant. Conclusions: Even brief, unguided use of this web-based tool improved knowledge and reduced decisional conflict for a diverse group of smokers considering lung cancer screening

A composite reference section for terminal Proterozoic strata of southern Namibia

Integrated sequence stratigraphic and chemostratigraphic data yield a framework for correlations of stratigraphic units in the terminal Proterozoic to Cambrian Witvlei and Nama Groups of Namibia. Coupled with precise U-Pb zircon age constraints, these correlations make it possible to construct a composite reference section for use in calibrating terminal Proterozoic chronostratigraphy. The Namibian reference section starts with two distinct glacial horizons and extends up to within 1 million years of the Proterozoic-Cambrian boundary. The two glacial horizons may represent each of two distinct Varanger-age glaciations better known from the North Atlantic region. From the higher of the two glacial horizons up, the composite stratigraphy preserves one of the thickest and most complete available records of carbon-isotope variability in post-Varanger terminal Proterozoic seawater. Four carbon-isotope chemostratigraphic intervals are recognized: (1) a postglacial negative δ^(13)C excursion (Npg interval); (2) a rising interval (Pr interval) of increasing positive delta 13 C values; (3) a falling interval (Pf interval) characterized by decreasing positive δ^(13)C and culminating in near zero or negative values; and (4) an interval of moderately positive, relatively invariant δ^(13)C values (I interval) that extends up to the unconformity that contains the Proterozoic-Cambrian boundary. Each of these chemostratigraphic intervals can be recognized in widely separated correlative sections around the world. By comparing sediment accumulation rate in the radiometrically calibrated Namibian stratigraphy with sediment accumulation rates in correlative sections in Arctic Canada and Oman, a maximum age of 564 Ma is estimated for the end of the younger Varanger glaciation, 25 m.y. younger than previous estimates