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The Composition Of Normative Groups And Diagnostic Decision Making: Shooting Ourselves In The Foot
Purpose: The normative group of a norm-referenced test is intended to provide a basis for interpreting test scores. However, the composition of the normative group may facilitate or impede different types of diagnostic interpretations. This article considers who should be included in a normative sample and how-this decision must be made relative to the purpose for which a test is intended. Method: The way in which the composition of the normative sample affects classification accuracy is demonstrated through a test review followed by a simulation study. The test review examined the descriptions of the normative group in a sample of 32 child language tests. The mean performance reported in the test manual for the sample of language impaired children was compared with the sample's norms, which either included or excluded children with language impairment. For the simulation, 2 contrasting normative procedures were modeled. The first procedure included a mixed group of representative cases (language impaired and normal cases). The second procedure excluded the language impaired cases from the norm. Results: Both the data obtained from test manuals and the data simulation based on population characteristics supported our claim that use of mixed normative groups decreases the ability to accurately identify language impairment. Tests that used mixed norms had smaller differences between the normative and language impaired groups in comparison with tests that excluded children with impairment within the normative sample. The simulation demonstrated mixed norms that lowered the group mean and increased the standard deviation, resulting in decreased classification accuracy. Conclusions: When the purpose of testing is to identify children with impaired language skills, including children with language impairment in the normative sample can reduce identification accuracy.Communication Sciences and Disorder
Construction and Calibration of a Streaked Optical Spectrometer for Shock Temperature
Here we describe the implementation and calibration of a streaked visible
spectrometer (SVS) for optical pyrometry and emission/absorption spectroscopy
on light gas gun platforms in the UC Davis Shock Compression Laboratory. The
diagnostic consists of an optical streak camera coupled to a spectrometer to
provide temporally and spectrally-resolved records of visible emission from
dynamically-compressed materials. Fiber optic coupling to the sample enables a
small diagnostic footprint on the target face and flexibility of operation on
multiple launch systems without the need for open optics. We present the
details of calibration (time, wavelength and spectral radiance) for absolute
temperature determination and present benchmark measurements of system
performance.Comment: 6 pages, 3 figures Davies, E., et al. (accepted). In J. Lane, T.
Germann, and M. Armstrong (Eds.), 21st Biennial APS Conference on Shock
Compression of Condensed Matter (SCCM19). AIP Publishin
Nonlinear dynamics of mode-locking optical fiber ring lasers
We consider a model of a mode-locked fiber ring laser for which the evolution of a propagating pulse in a birefringent optical fiber is periodically perturbed by rotation of the polarization state owing to the presence of a passive polarizer. The stable modes of operation of this laser that correspond to pulse trains with uniform amplitudes are fully classified. Four parameters, i.e., polarization, phase, amplitude, and chirp, are essential for an understanding of the resultant pulse-train uniformity. A reduced set of four coupled nonlinear differential equations that describe the leading-order pulse dynamics is found by use of the variational nature of the governing equations. Pulse-train uniformity is achieved in three parameter regimes in which the amplitude and the chirp decouple from the polarization and the phase. Alignment of the polarizer either near the slow or the fast axis of the fiber is sufficient to establish this stable mode locking
Examination of Factors Influencing Crop Insurance Purchase Decisions of Illinois Farmers
Farm Management, Risk and Uncertainty,
Crop Insurance Purchase Decisions: A Study of Northern Illinois Farmers
When selecting crop insurance coverage, farmers must consider multiple factors. The importance associated with factors that are considered when making crop insurance decisions varies among individual farmers. As available crop insurance options increase, selecting the appropriate coverage becomes a more complicated process. The prevalence of crop insurance participation and the existence of multiple selection criteria also makes understanding participant decisions more difficult. This paper provides findings of a mail survey conducted among farmers in northern Illinois. Mainly, this paper examines factors influencing farmers’ crop insurance purchase decisions, types of coverage purchased, and farmers’ risk attitudes.Crop Production/Industries,
Ethanol Marketing and Input Procurement Practices of U.S. Ethanol Producers: 2008 Survey Results
A mail survey was used to collect information about input procurement and ethanol and co-product marketing practices from 60 U.S. ethanol production facilities. Data were used to answer questions about the conduct or behavior of ethanol producers. It was anticipated that firm conduct or behavior would be fairly homogeneous because the ethanol industry was in Stage II of the industry life-cycle, and societal support for ethanol production resulted in large volumes of publicly available information about technology and markets. Age of facility, size of facility, and type of ownership jointly explained a limited number of differences in responses across ethanol facilities, thus supporting the concept of fairly homogeneous conduct or behavior.entry timing, ethanol, farmer-owned cooperatives, industry life-cycle, Agribusiness, Resource /Energy Economics and Policy, Q11, Q42,
Short term doxycycline treatment induces sustained improvement in myocardial infarction border zone contractility.
Decreased contractility in the non-ischemic border zone surrounding a MI is in part due to degradation of cardiomyocyte sarcomeric components by intracellular matrix metalloproteinase-2 (MMP-2). We recently reported that MMP-2 levels were increased in the border zone after a MI and that treatment with doxycycline for two weeks after MI was associated with normalization of MMP-2 levels and improvement in ex-vivo contractile protein developed force in the myocardial border zone. The purpose of the current study was to determine if there is a sustained effect of short term treatment with doxycycline (Dox) on border zone function in a large animal model of antero-apical myocardial infarction (MI). Antero-apical MI was created in 14 sheep. Seven sheep received doxycycline 0.8 mg/kg/hr IV for two weeks. Cardiac MRI was performed two weeks before, and then two and six weeks after MI. Two sheep died prior to MRI at six weeks from surgical/anesthesia-related causes. The remaining 12 sheep completed the protocol. Doxycycline induced a sustained reduction in intracellular MMP-2 by Western blot (3649±643 MI+Dox vs 9236±114 MI relative intensity; p = 0.0009), an improvement in ex-vivo contractility (65.3±2.0 MI+Dox vs 39.7±0.8 MI mN/mm2; p<0.0001) and an increase in ventricular wall thickness at end-systole 1.0 cm from the infarct edge (12.4±0.6 MI+Dox vs 10.0±0.5 MI mm; p = 0.0095). Administration of doxycycline for a limited two week period is associated with a sustained improvement in ex-vivo contractility and an increase in wall thickness at end-systole in the border zone six weeks after MI. These findings were associated with a reduction in intracellular MMP-2 activity
Pathogen propagation in cultured three-dimensional tissue mass
A process for propagating a pathogen in a three-dimensional tissue mass cultured at microgravity conditions in a culture vessel containing culture media and a culture matrix is provided. The three-dimensional tissue mass is inoculated with a pathogen and pathogen replication in the cells of the tissue mass achieved
Deprivation, Violence, and Identities: Mapping Contemporary World Conflicts
The University Archives has determined that this item is of continuing value to OSU's history.With the collapse of the Soviet Union, many anticipated the advent of a “new world order” of global
capitalism, or even an “end to history,” implying that conflicts based on ideology and competing
national interests and identities would lose their political relevance in the post-Cold War era. Quite to
the contrary, the 1990s saw an upwelling of ethnic and religious violence in locations as disparate as the
former Yugoslavia, Central Africa, South Asia, and the Middle East. Prior to the events of 9/11, the
structure of international relations had still made it possible to imagine that such conflicts had local roots
and were thus exclusively of regional consequence. The events of 9/11, however, rendered undeniable
the global significance of local ethnic and religious-based differences. It is now an inescapable
conclusion that social identities are everywhere threatened from within by local and ethnic formations,
conditioned in their response by the prerogatives and ambitions of the state and its actors, and
transformed from without by the global flows of capital, popular culture, and transnational ideologies
and populations. As features of the contemporary world, deprivation, violence, and identities are but the
local manifestations of the conflict between global systems of thought, power, and authority.Ohio State University. Center for African StudiesOhio State University. Office of International AffiarsOhio State University. East Asian Studies CenterOhio State University. Center for Slavic and East European StudiesOhio State University. Middle East Studies CenterOhio State University. Office of International Affairs. Clusters of Interdisciplinary Research on International Themes (CIRIT)Ohio State University. Center for Latin American StudiesOhio State University. Mershon Center for International Security StudiesEvent webpage, event summar
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