266 research outputs found
Issues in Evaluating Health Department Web-Based Data Query Systems: Working Papers
Compiles papers on conceptual and methodological topics to consider in evaluating state health department systems that provide aggregate data online, such as taxonomy, logic models, indicators, and design. Includes surveys and examples of evaluations
Whatâs the Story Here? How Catholic University Leaders are Making Sense of Undocumented Student Access.
This study examines how leaders make sense of an unsettled, contemporary issue facing
higher education. It deepens our understanding of how stories may operate in the process of
sensemaking, which has been described as âthe experience of being thrown into an ongoing,
unknowable, unpredictable streaming of experience in search of answers to the question, âWhat's
the story?ââ (Weick, 2008, para. 1). Sensemaking is a powerful tool for understanding how
people engage volatile issues.
The study addresses two research questions: How are Catholic university leaders making
sense of undocumented student access? and What role do stories play in the sensemaking of
these leaders? Situating the study in Catholic higher education, with its own unique historyâ
serving as a vehicle for assimilation into American society, especially for immigrantsâallows us
to explore the spiritual and religious values that operate differently within this sector than
elsewhere in U.S. higher education. That the issue remains unsettled in policy and practice
highlights the effects of volatility on sensemaking.
To learn more about how leaders respond to the challenge of this situation, I conducted
55 interviews in 12 Catholic universities in regions of the U.S. with relatively high
undocumented populations. I find that identity, social context, extracted cues, and stories play
especially important roles in leader sensemaking. Leaders engaged in âconstructing Catholic
identity,â a process of reflection upon the espoused mission values in their institutions which led
to the decision to admit undocumented students. Because of the volatility of undocumented
access and leadersâ fear of negative consequences resulting from engaging the issue, leaders
employed numerous behaviors to manage their commitment (Salancik, 1977). This resulted in
strategic ambiguity that provided some protection for leaders; it also led to communication
breakdowns in universities and the alienation of important institutional leaders.
Canonical stories played an important role in sensemaking, as leaders referred to
âcommunity narrativesâ and âdominant cultural narrativesâ (Rappaport, 2000), often alluding to
them in shorthand. Because their meaning is shared among group members, canonical stories
were especially useful as leaders reflected on the link between institutional histories and
charisms and the decision to admit undocumented students.PhDHigher EducationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111516/1/djpcsc_1.pd
The Dynamics of Rayleigh-Taylor Stable and Unstable Contact Discontinuities with Anisotropic Thermal Conduction
We study the effects of anisotropic thermal conduction along magnetic field
lines on an accelerated contact discontinuity in a weakly collisional plasma.
We first perform a linear stability analysis similar to that used to derive the
Rayleigh-Taylor instability (RTI) dispersion relation. We find that anisotropic
conduction is only important for compressible modes, as incompressible modes
are isothermal. Modes grow faster in the presence of anisotropic conduction,
but growth rates do not change by more than a factor of order unity. We next
run fully non-linear numerical simulations of a contact discontinuity with
anisotropic conduction. The non-linear evolution can be thought of as a
superposition of three physical effects: temperature diffusion due to vertical
conduction, the RTI, and the heat flux driven buoyancy instability (HBI). In
simulations with RTI-stable contact discontinuities, the temperature
discontinuity spreads due to vertical heat conduction. This occurs even for
initially horizontal magnetic fields due to the initial vertical velocity
perturbation and numerical mixing across the interface. The HBI slows this
temperature diffusion by reorienting initially vertical magnetic field lines to
a more horizontal geometry. In simulations with RTI-unstable contact
discontinuities, the dynamics are initially governed by temperature diffusion,
but the RTI becomes increasingly important at late times. We discuss the
possible application of these results to supernova remnants, solar prominences,
and cold fronts in galaxy clusters.Comment: 18 pages, 15 figures, submitted to MNRA
In Vitro Assay for Phototoxic Chemicals
The photosensitizing potential of chemicals known to produce photosensitivity in humans was compared to chemicals not considered to be photosensitizers in an in vitro assay. The assay involved exposure of human lymphoid cells to UVA (320â400 nm), and in some cases UVB (280-320 nm) radiation, in the presence of the chemicals and the assessment of phototoxicity as measured by the incorporation of 3[H]-thymidine into nuclear DNA. All known photosensitizers tested were found to be phototoxic, while the nonphotosensitizing agents, with the exception of retinoic acid, were not phototoxic. Peripheral blood mononuclear cells were compared to a T lymphoblastoid cell line as target cells; the latter were superior in terms of convenience, cost and reproducibility of results. This test system has potential as a predictive assay for detecting additional phototoxic chemicals
Chemical Study of the Interstitial Water Dissolved Organic Matter and Gases in Lake Erie, Cleveland Harbor, and Hamilton Harbour Bottom Sediments - Composition and Fluxes to Overlying Waters
The research on which this report is based was financed in part by the U.S. Department
of the Interior, as authorized by the Water Research and Development Act of 1978
(P.L. 95-467).(print) iv, 167, [45] p. : ill., maps ; 29 cm.FINAL REPORT FOR OWRT GRANT A-O59-OHIOItem lacks publication date. Issue date supplied from hand-written year on coverIntroduction -- The Study Area -- Methods and Materials -- Results -- Discussion -- Conclusions -- Selected Bibliographic References -- Tables 1-32 -- Figures 1-36 -- Appendi
Distribution of O-Acetylated Sialic Acids among Target Host Tissues for Influenza Virus.
Sialic acids (Sias) are important glycans displayed on the cells and tissues of many different animals and are frequent targets for binding and modification by pathogens, including influenza viruses. Influenza virus hemagglutinins bind Sias during the infection of their normal hosts, while the encoded neuraminidases and/or esterases remove or modify the Sia to allow virion release or to prevent rebinding. Sias naturally occur in a variety of modified forms, and modified Sias can alter influenza virus host tropisms through their altered interactions with the viral glycoproteins. However, the distribution of modified Sia forms and their effects on pathogen-host interactions are still poorly understood. Here we used probes developed from viral Sia-binding proteins to detect O-acetylated (4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl) Sias displayed on the tissues of some natural or experimental hosts for influenza viruses. These modified Sias showed highly variable displays between the hosts and tissues examined. The 9-O-acetyl (and 7,9-) modified Sia forms were found on cells and tissues of many hosts, including mice, humans, ferrets, guinea pigs, pigs, horses, dogs, as well as in those of ducks and embryonated chicken egg tissues and membranes, although in variable amounts. The 4-O-acetyl Sias were found in the respiratory tissues of fewer animals, being primarily displayed in the horse and guinea pig, but were not detected in humans or pigs. The results suggest that these Sia variants may influence virus tropisms by altering and selecting their cell interactions. IMPORTANCE Sialic acids (Sias) are key glycans that control or modulate many normal cell and tissue functions while also interacting with a variety of pathogens, including many different viruses. Sias are naturally displayed in a variety of different forms, with modifications at several positions that can alter their functional interactions with pathogens. In addition, Sias are often modified or removed by enzymes such as host or pathogen esterases or sialidases (neuraminidases), and Sia modifications can alter those enzymatic activities to impact pathogen infections. Sia chemical diversity in different hosts and tissues likely alters the pathogen-host interactions and influences the outcome of infection. Here we explored the display of 4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl modified Sia forms in some target tissues for influenza virus infection in mice, humans, birds, guinea pigs, ferrets, swine, horses, and dogs, which encompass many natural and laboratory hosts of those viruses
Microwave and Millimeter Wave Techniques
Contains reports on two research project.Joint Services Electronics Program (Contract DAABO7-76-C-1400
Very Shallow Water Bathymetry Retrieval from Hyperspectral Imagery at the Virginia Coast Reserve (VCR\u2707) Multi-Sensor Campaign
A number of institutions, including the Naval Research Laboratory (NRL), have developed look up tables for remote retrieval of bathymetry and in-water optical properties from hyperspectral imagery (HSI) [6]. For bathymetry retrieval, the lower limit is the very shallow water case (here defined as \u3c 2m), a depth zone which is not well resolved by many existing bathymetric LIDAR sensors, such as SHOALS [4]. The ability to rapidly model these shallow water depths from HSI directly has potential benefits for combined HSI/LIDAR systems such as the Compact Hydrographic Airborne Rapid Total Survey (CHARTS) [10]. In this study, we focused on the validation of a near infra-red feature, corresponding to a local minimum in absorption (and therefore a local peak in reflectance), which can be correlated directly to bathymetry with a high degree of confidence. Compared to other VNIR wavelengths, this particular near-IR feature corresponds to a peak in the correlation with depth in this very shallow water regime, and this is a spectral range where reflectance depends primarily on water depth (water absorption) and bottom type, with suspended constituents playing a secondary role
Use of Fatty Acid Analysis to Determine Dispersal of Caspian Terns in the Columbia River Basin, U.S.A.
Lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. In populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. Within the Columbia River Basin (Washington, U.S.A.), avian predators forage at dams because dams tend to reduce rates of emigration of juvenile salmonids (Oncorhynchus spp.), artificially concentrating these prey. We used differences in fatty acid profiles between Caspian Terns (Hydroprogne caspia) at coastal and inland breeding colonies and terns culled by a lethal control program at a mid-Columbia River dam to infer dispersal patterns. We modeled the rate of loss of fatty acid biomarkers, which are fatty acids that can be traced to a single prey species or groups of species, to infer whether and when terns foraging at dams had emigrated from the coast. Nonmetric multidimensional scaling showed that coastal terns had high levels of C20 and C22 monounsaturated fatty acids, whereas fatty acids of inland breeders were high in C18:3n3, C20:4n6, and C22:5n3. Models of the rate of loss of fatty acid showed that approximately 60% of the terns collected at Rock Island Dam were unlikely to have bred successfully at local (inland) sites, suggesting that terns foraging at dams come from an extensive area. Fatty acid biomarkers may provide accurate information about patterns of dispersal in animal populations and may be extremely valuable in cases where populations differ demonstrably in prey base
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