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Title:
Examining Item Parameter Drift as a Source of Construct Shift
Description:
Item parameter drift (IPD) is defined as differential change in item parameters or ability estimates over time or testing occasions. Unlike previous IPD studies that have focused on change in item parameters over time, this study examined IPD to detect change in item parameters (construct shift) between grade levels within a single time point. Data for this study come from the Minnesota Student Survey (MSS). Hierarchical general linear modeling (HGLM) framework was used for examining IPD in the items of “being bullied” and “school climate” scales from the MSS. Results indicated that almost all of the items drift across grade levels (6th, 9th, and 12th). This suggests that being bullied and school climate constructs are not invariant across grade levels.
Author/Creators:
Okan Bulut
Title:
marino_angela_201802_MFA.pdf
Description:
Author/Creators:
Angela Marino
Title:
Giant cabbages in the flowerbed at Bear Lodge, Fairbanks, Alaska
Description:
Because of the 24 hour sunlight, plants in Fairbanks grow very large. These cabbages were in one of the flower beds at the Bear Lodge.
Author/Creators:
Campbell, Sandy
Title:
Toward a Theory of Library and Information Science
Description:
The present inquiry addresses the problem of an adequate definition of the domain of library and information science. Such a definition must be formulated according to the rigor of logic, for it is patent that mapping out a scholarly domain is more than an act of self-evident discovery. Discourse about a domain does not arrange itself in social reality; it must be rendered explicit. Concepts must be expressed as a system of linguistic terms. Such a terminological system is a necessary condition for the development among a community of researchers and practitioners of a consensus on the fundamental problems posed in their inquiry and service activities. Without this consensus in the community, progress in conceptualization is impeded, and so knowledge cannot advance. The present research applies logical and conceptual analysis to the task of defining the domain of library and information science. First, extant definitions are examined from the literature (in English, to 1981) and their diverse usage of terms is set forth. Basic concepts are identified and for each basic concept the synonymous terms are brought together. In this way a typology of generic definitions is developed. Then, the logical adequacy of each generic definition is considered. The analysis reveals a profound depth of confusion, disagreement, contradiction, and inconsistency over the past 100 years about the proper characterization of the domain. More than 1,500 definitions of it are documented here, and they contain over 340 synonymous, quasi-synonymous, and pseudo-synonymOus terms purporting to capture its essence. Nowhere are the flawed claims more apparent than in the efforts to tease apart a domain of information science (itself only one among many fuzzy terms) from that of library science. The dissertation then introduces the S1GGS metatheory, an extension of general system theory, as a way of enhancing domain conceptualization. In this enhancement, library and information science is taken to be a system of human social practice in which one person facilitates access to selected cultural objects on behalf of another person who is seeking access to them. The practice so characterized is the 'symbolic culture accessing system'. The present work argues that this conception provides a more adequate and more powerful description of the domain than those definitions so far posited. As such, it constitutes a rudimentary descriptive theory of library and information science and so holds some promise of focusing the community's long-awaited consensus.
Author/Creators:
Alvin M. Schrader
Title:
thesis ERA A. Marino.pdf
Description:
Author/Creators:
Angela Marino
Title:
Mechanics of an elastic solid reinforced with bidirectional fiber in finite plane elastostatics: complete analysis
Description:
A continuum-based model is presented for the mechanics of bidirectional composites subjected to finite plane deformations. This is framed in the development of a constitutive relation within which the constraint of material incompressibility is augmented. The elastic resistance of the fibers is accounted for directly via the computation of variational derivatives along the lengths of bidirectional fibers. The equilibrium equation and necessary boundary conditions are derived by virtue of the principles of virtual work statement. A rigorous derivation of the corresponding linear theory is developed and used to obtain a complete analytical solution for small deformations superposed on large. The proposed model can serve as an alternative 2D Cosserat theory of nonlinear elasticity.
Author/Creators:
Mahdi Zeidi
Title:
Troponin degradation products: more specific marker for myocardial infarction
Description:
Introduction Myocardial infarction (MI) is the death of cardiac muscle in the setting of severe ischemia (lack of oxygen and nutrient supply). Assay of serum troponin I (TnI) is the biochemical gold standard for detecting MI. With the development of high sensitivity assays, TnI is being detected in milder conditions such as reversible tachycardia or myocardial ischemia in the absence of radiologic evidence for infarct. Different types of MI are classified clinically: type 1 MI being the classic “heart attack” where the irreversible infarct necessitates a timely intervention. In contrast, type 2 MI is precipitated by a physiologic stressor (e.g. tachyarrhythmia, sepsis, or anemia) that causes ischemia in vulnerable regions of the heart. It is very important to differentiate irreversible infarct from reversible ischemia with a novel biomarker because the treatments are very different. Rationale While the mechanisms leading to TnI release are poorly understood, it is generally accepted that intracellular proteases are differentially activated in ischemia and in cell death. Cardiac TnI has intrinsically disordered N- and C-terminal ends that are exposed and vulnerable to proteolytic digestion. TnI proteolysis products may be more rational and specific markers for irreversible cardiomyocyte death than its total level in the blood. Methods We collected blood samples from 29 hospitalised patients with elevated cTnI. We quantitated proteolytic degradation using sandwich ELISAs to specifically detect the N-terminal, core, or C-terminal regions of TnI using commercial antibodies (M18, MF4, and 560, respectively). Results We observed a wide variation in the degree of proteolytic degradation of TnI across the patients’ samples. Interestingly, degradation of TnI at both N- and C-termini in type 1 MI samples was detected. However, the C-terminus degradation was more robust, consistent and proportional to the severity of the infarct. On the other hand, there was less degradation observed in type 2 MI samples, indicating that TnI is released in a more intact form. Conclusions Proteolytic degradation of TnI at its C-terminus is a more specific marker for clinically significant MI than total TnI level. Making a distinction between intact and degraded forms of TnI may be useful for identifying patients with focal infarct in need of urgent revascularization and monitoring intracellular proteolysis as a possible target for therapeutic intervention.
Author/Creators:
Somaya Zahran
Title:
Proteolytic Digestion of Serum Cardiac Troponin I as Marker of Ischemic Severity
Description:
Background: The serum troponin assay is the biochemical gold standard for detecting myocardial infarction (MI). A major diagnostic issue is that some believe troponin levels can rise with reversible injury, in the absence of radiologically detectable infarct. Hypothesis: Because cell death activates intracellular proteases, troponin released by irreversible infarct will be more proteolyzed than that released by milder processes. Our goal was to quantify proteolytic digestion of cardiac troponin I in patients with varying degrees of myocardial injury. Methods: Serum or plasma samples from 29 patients with cardiac troponin I elevations were analyzed for proteolytic degradation, using 3 different sandwich ELISAs designed to specifically detect the N-terminal, core, or C-terminal regions of cardiac troponin I. Results: As predicted, the degree of proteolytic digestion increased with increasing severity of injury, as estimated by the total troponin level, and this trend was more pronounced for C-terminal (vs N-terminal) degradation. The highest degree of proteolytic digestion was observed in patients with ST-elevation MI; the least, in type 2 MI (supply–demand ischemia rather than acute thrombus formation). Conclusions: The proteolytic degradation pattern of cardiac troponin I may be a better indicator of clinically significant MI than total serum troponin level. Distinguishing between intact and degraded forms of troponin may be useful for (a) identifying those patients with clinically significant infarct in need of revascularization, (b) monitoring intracellular proteolysis as a possible target for therapeutic intervention, and (c) providing an impetus for standardizing the epitopes used in the troponin I assay
Author/Creators:
Somaya Zahran
Title:
Places, names, and linked data modelling
Description:
Linked data aims to represent and disambiguate discrete entities with unique identifiers, but the relationships between places and their names are not always straightforward. This brief presentation describes certain issues encountered when modelling places in linked data, and proposes technological and philosophical approaches that merit further exploration.
Author/Creators:
Huck, John
Title:
Fountainhead Antique Auto Museum, Fairbanks, Alaska
Description:
The Fountainhead Antique Auto Museum, contains a world-class collection of antique automobiles and machinery. In this image a steel-wheeled traction engine sits outside of the museum building. The collection is complemented by a collection of period fashion clothing. Individual pieces of clothing are exhibited alongside cars of the appropriate time period. The collection was created as a tourist attraction. A few of the cars and garments have Alaskan provenance, but most of the objects in the collections were acquired elsewhere, many from the lower 48 States, transported to Fairbanks.
Author/Creators:
Campbell, Sandy
Title:
Pink Cadillac with Texas longhorn hood ornament
Description:
This pink Cadillac was parked in front of a Fred Meyer store in Fairbanks, Alaska. The hood ornament, which spans the width of the car, is a pair of Texas Longhorn horns joined together with studded leather strips and fine rope. The horns are mounted on a piece of painted wood, centered on the hood, towards the front, above the Cadillac symbol. The horns are fairly flat and point down at the tips. In this particular form of automobile decoration, the horns are more often mounted pointing up. The car has a yellow and black Alaska license plate.
Author/Creators:
Campbell, Sandy
Title:
Wander Lake in the Wedgewood Wildlife Sanctuary, Fairbanks, Alaska
Description:
Wander Lake is within the 75 acre Wedgewood Wildlife Sanctuary. There are several hiking trails in the Sanctuary, including one that loops around the lake.
Author/Creators:
Campbell, Sandy
Title:
Door handles with paw prints at the Bear Lodge in Fairbanks, Alaska
Description:
At the Bear Lodge in Fairbanks, Alaska, are cast metal rectangles with bear paw prints on them. They are mounted on metal rails cast to look like tree branches.
Author/Creators:
Campbell, Sandy
Title:
Data associated with Grant et al (MER) "Suspended sediment causes feeding current arrests in the glass sponge Aphrocallistes vastus"
Description:
Bottom-contact trawling generates large, moving clouds of suspended sediments that can alter the behaviour of organisms adjacent to trawl paths. While increased suspended sediment concentrations (SSCs) are known to cause glass sponges to arrest filtration in lab studies, the response of sponges to sediment in situ is not yet known. Here we describe arrest behaviours in response to increased SSCs recorded from the glass sponge Aphrocallistes vastus at the Fraser Ridge sponge reef in the Strait of Georgia, British Columbia, Canada. We identified 23 arrests of the sponges’ feeding current during experimental disturbances that raised SSC to between 10 and 80 mg l-1. Single arrests lasted 4.25 ± 1.3 min (± SD) and were characterized by a 2 cm s-1 reduction in feeding current lasting 0.5 - 3 min (mean 1.91 ± 0.97 min, n = 19). In comparison, coughing arrests varied in length (31 ± 22.89 min) and lasted 4 - 15 min (10.46 ± 5.26 min, n = 4). Coughing arrests showed a distinctive on/off pattern as sponge filtration returned to normal excurrent velocities, distinguishing them from single arrests. The onset of both arrest types was correlated with elevated SSCs (r = -0.83 to -0.92). Natural SSCs at the reef averaged 4.4 mg l-1 and were correlated with tidal flow (r = 0.86 and 0.89). The combined data provide evidence that suspended sediments can stop glass sponge feeding in situ even at SSCs below those known to be generated by trawling.
Author/Creators:
Nathan Grant

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