SLIDES: Why Public Lands? A Question Not Addressed 40 Years Ago

Presenter: Thomas Michael Power, Consulting Economist, Power Consulting; Research Professor and Professor Emeritus, Economics Department, University of Montana (Missoula, MT) 17 slide

SLIDES: Why Public Lands? A Question Not Addressed 40 Years Ago

Presenter: Thomas Michael Power, Consulting Economist, Power Consulting; Research Professor and Professor Emeritus, Economics Department, University of Montana (Missoula, MT) 17 slide

Le design pédagogique dans un contexte de bimodalisation de l'enseignement supérieur : une étude multicas

La présente recherche porte sur l’étude de l’apprentissage en ligne au niveau des établissements d’enseignement supérieur qui offrent à la fois des cours sur campus et à distance, en d’autres mots des établissements « bimodaux ». À travers une analyse des pratiques courantes en matière de design pédagogique dans le domaine de l’apprentissage en ligne et dix études de cas, cette recherche a visé le développement d’un modèle de design pédagogique adapté aux besoins et aux ressources du corps professoral d’une université bimodale.This dissertation deals with on-line learning in universities which offer courses both on campus and at a distance or, in other words, « dual-mode universities ». Based on an analysis of current instructional systems design practice as implemented in on-line learning and on ten case studies, the purpose of this dissertation was to develop an instructional systems design prototype adapted to needs and resources of faculty at a staff at a dual-mode university

On the theory of ambipolar diffusion, with applications to astrophysical jets

1 online resource (x, 67 p.) : illustrations (chiefly colour)Includes abstract and appendices.Includes bibliographical references (p. 65-67).Numerically simulated magnetohydrodynamical jets are not at all morphologically similar to most of those which are observed in nature. Jets in nature are actually quite morphologically similar to pure hydrodynamical simulations. However, it is well known that jets in nature are launched magnetically and likely transport dynamically important magnetic fields. Therefore, a gap seems to exist in the model of jets based upon a pure magnetohydrodynamical outflow. In this thesis, I show that the theory of ambipolar diffusion may provide a plausible solution to the morphology problem by running simulations which use the non-isothermal single fluid approximation of ambipolar diffusion. However, using resolution studies on the numerical simulations, I show that there exists a numerical instability caused by the single fluid approximation which produces unreliable results when applied to this problem. Accordingly, I develop a full non-isothermal two-fluid model of ambipolar diffusion from first principles and show that this reduces correctly to the single fluid model of ambipolar diffusion widely used in the literature. Suggestions on how this may be incorporated into a numerical model are then made

Survey of Obstetrician-Gynecologists in the United States About Toxoplasmosis

Background: Although the incidence of toxoplasmosis is low in the United States, up to 6000 congenital cases occur annually. In September 1998, the Centers for Disease Control and Prevention held a conference about toxoplasmosis; participants recommended a survey of the toxoplasmosis-related knowledge and practices of obstetrician-gynecologists and the development of professional educational materials for them. Methods: In the fall of 1999, surveys were mailed to a 2% random sample of American College of Obstetricians and Gynecologists (ACOG) members and to a demographically representative group of ACOGmembers known as the Collaborative Ambulatory Research Network (CARN). Responses were not significantly different for the random and CARN groups for most questions (p value shown when different). Results: Among 768 US practicing ACOG members surveyed, 364 (47%) responded. Seven per cent (CARN 10%, random 5%) had diagnosed one or more case(s) of acute toxoplasmosis in the past year. Respondents were well-informed about how to prevent toxoplasmosis. However, only 12% (CARN 11%, random 12%) indicated that a positive Toxoplasma IgM test might be a false–positive result, and only 11% (CARN 14%, random 9%) were aware that the Food and Drug Administration sent an advisory to all ACOG members in 1997 stating that some Toxoplasma IgM test kits have high false–positive rates. Most of those surveyed (CARN 70%, random 59%; X(2) p < 0.05) were opposed to universal screening of pregnant women. Conclusions: Many US obstetrician-gynecologists will encounter acute toxoplasmosis during their careers, but they are frequently uncertain about interpretation of the laboratory tests for the disease. Most would not recommend universal screening of pregnant women

CubeSat Single-Photon Detector Module for Performing In-Orbit Laser Annealing to Heal Radiation Damage

Silicon-based single-photon avalanche photodiodes (SPADs), widely considered for satellite-based quantum communications, suffer a constant increase of dark count rate (DCR) from radiation-induced proton displacement damage in their active areas. When this accumulated damage causes the DCR to exceed a certain threshold (for example, 10,000 counts per second), the SPADs become unreliable for quantum communications, limiting mission lifetime. Previous ground experiments showed that radiation-induced DCR of synthetically irradiated SPADs could be significantly improved by high-power laser annealing, a localized heating of SPADs’ active areas using a focused laser beam. The next step is therefore to demonstrate realtime laser annealing on constantly irradiated SPADs in actual low-Earth-orbit is viable. To facilitate this study, the University of Waterloo team built a miniaturized software controllable SPAD module as part of the annealing payload on CAPSat (Cool Annealing Payload Satellite), a 3U CubeSat satellite developed by a team from the University of Illinois Urbana-Champaign. We present the concept of in-orbit laser annealing and the electronic platform of the SPAD module containing four detectors supporting thermal and laser annealing and detector characterization. The CAPSat, launched and deployed in a low-Earth orbit at 400 km altitude from the International Space Station in October 2021, was intended to assess the viability of this approach before incorporating SPADs in future quantum satellite missions, especially in quantum receivers

Midlife and Late-Life Vascular Risk Factors and White Matter Microstructural Integrity: The Atherosclerosis Risk in Communities Neurocognitive Study.

BACKGROUND: Diffusion tensor imaging measures of white matter (WM) microstructural integrity appear to provide earlier indication of WM injury than WM hyperintensities; however, risk factors for poor WM microstructural integrity have not been established. Our study quantifies the association between vascular risk factors in midlife and late life with measures of late-life WM microstructural integrity. METHODS AND RESULTS: We used data from 1851 participants in ARIC (Atherosclerosis Risk in Communities Study) who completed 3-T magnetic resonance imaging, including diffusion tensor imaging, as part of the ARIC Neurocognitive Study (ARIC-NCS). We quantified the association among lipids, glucose, and blood pressure from the baseline ARIC visit (1987-1989, ages 44-65, midlife) and visit 5 of ARIC (2011-2013, ages 67-90, late life, concurrent with ARIC-NCS) with regional and overall WM mean diffusivity and fractional anisotropy obtained at ARIC visit 5 for ARIC participants. We also considered whether these associations were independent of or modified by WM hyperintensity volumes. We found that elevated blood pressure in midlife and late life and elevated glucose in midlife, but not late life, were associated with worse late-life WM microstructural integrity. These associations were independent of the degree of WM hyperintensity, and the association between glucose and WM microstructural integrity appeared stronger for those with the least WM hyperintensity. There was little support for an adverse association between lipids and WM microstructural integrity. CONCLUSIONS: Hypertension in both midlife and late life and elevated glucose in midlife are related to worse WM microstructural integrity in late life

Development of an Ion Thruster and Power Processor for New Millennium's Deep Space 1 Mission

The NASA Solar Electric Propulsion Technology Applications Readiness Program (NSTAR) will provide a single-string primary propulsion system to NASA's New Millennium Deep Space 1 Mission which will perform comet and asteroid flybys in the years 1999 and 2000. The propulsion system includes a 30-cm diameter ion thruster, a xenon feed system, a power processing unit, and a digital control and interface unit. A total of four engineering model ion thrusters, three breadboard power processors, and a controller have been built, integrated, and tested. An extensive set of development tests has been completed along with thruster design verification tests of 2000 h and 1000 h. An 8000 h Life Demonstration Test is ongoing and has successfully demonstrated more than 6000 h of operation. In situ measurements of accelerator grid wear are consistent with grid lifetimes well in excess of the 12,000 h qualification test requirement. Flight hardware is now being assembled in preparation for integration, functional, and acceptance tests

The Role of Vector Trait Variation in Vector-Borne Disease Dynamics

Many important endemic and emerging diseases are transmitted by vectors that are biting arthropods. The functional traits of vectors can affect pathogen transmission rates directly and also through their effect on vector population dynamics. Increasing empirical evidence shows that vector traits vary significantly across individuals, populations, and environmental conditions, and at time scales relevant to disease transmission dynamics. Here, we review empirical evidence for variation in vector traits and how this trait variation is currently incorporated into mathematical models of vector-borne disease transmission. We argue that mechanistically incorporating trait variation into these models, by explicitly capturing its effects on vector fitness and abundance, can improve the reliability of their predictions in a changing world. We provide a conceptual framework for incorporating trait variation into vector-borne disease transmission models, and highlight key empirical and theoretical challenges. This framework provides a means to conceptualize how traits can be incorporated in vector borne disease systems, and identifies key areas in which trait variation can be explored. Determining when and to what extent it is important to incorporate trait variation into vector borne disease models remains an important, outstanding question