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Sustaining Argument: Centralizing the Role of the Writing Center in Program Assessment
In âWhy Assessment?â (2009), Gerald Graff argues that the critical conversations arising from regular program assessment are often as important as the actual findings themselves: outcomes assessment, he writes, is not only fundamental to measuring studentsâ performance, but potentially âtransformativeâ in terms of creating a recognizable dialogue about â and a more lively institutional culture of â good teaching (153). Agreeing with Graffâs claim, I argue that writing centers should take an active, if not central, role in the assessment of writing program outcomes by positioning themselves at the center of the evaluation process. My experiences as a writing center director involved in our universityâs less-than-three-year-old writing program assessment has led me to this conclusion.University Writing Cente
Cellular distribution of the prion protein in palatine tonsils of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni)
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) that affects members of the Cervidae family, including deer (Odocoileus spp.), elk (Cervus Canadensis spp.), and moose (Alces alces spp.). While CWD is a neurodegenerative disease, lymphoid accumulation of the abnormal isoform of the prion protein (PrPSc) is detectable early in the course of infection. It has been shown that a large portion of the PrPSc lymphoid accumulation in infected mule deer takes place on the surface of follicular dendritic cells (FDCs). In mice, FDC expression of PrPC has been shown to be essential for PrPSc accumulation. FDCs have been shown to normally express high levels of PrPC in mice and humans but this has not been examined in natural hosts for CWD. We used double immunofluorescent labeling and confocal microscopy to determine the PrPC expression characteristics of B and T lymphocytes as well as FDCs in palatine tonsils of CWD-negative mule deer and elk. We detected substantial PrPC colocalization with all cellular phenotypic markers used in this study, not just with FDC phenotypic markers
Nonparametric inference for competing risks current status data with continuous, discrete or grouped observation times
New methods and theory have recently been developed to nonparametrically
estimate cumulative incidence functions for competing risks survival data
subject to current status censoring. In particular, the limiting distribution
of the nonparametric maximum likelihood estimator and a simplified "naive
estimator" have been established under certain smoothness conditions. In this
paper, we establish the large-sample behavior of these estimators in two
additional models, namely when the observation time distribution has discrete
support and when the observation times are grouped. These asymptotic results
are applied to the construction of confidence intervals in the three different
models. The methods are illustrated on two data sets regarding the cumulative
incidence of (i) different types of menopause from a cross-sectional sample of
women in the United States and (ii) subtype-specific HIV infection from a
sero-prevalence study in injecting drug users in Thailand.Comment: 16 pages, 3 figure
A study of the relationship between the amount of parental reading to the student at home and the student\u27s second grade standardized reading achievement score
The purpose of this study was to investigate the relationship between the amount of time parents spent reading to their child at home and the child\u27 s second grade standardized reading achievement score. This study used a parental survey to question the parents of third grade students in an urban elementary school on their reading habits and those of the student.
Forty-eight parents (n=48) responded to the survey. The results were then analyzed to find the significance of a relationship. A Chi-square analysis indicated that there was no significant relationship between the amount of time a parent spends reading to a child and the child\u27s second grade standardized reading achievement score [Ď2 = 8.6, df = 5, p = .05]. Therefore, it was concluded that the amount of time spent reading to a child did not significantly increase the child\u27s second grade standardized reading test score
A Markov Chain Monte Carlo Algorithm for analysis of low signal-to-noise CMB data
We present a new Monte Carlo Markov Chain algorithm for CMB analysis in the
low signal-to-noise regime. This method builds on and complements the
previously described CMB Gibbs sampler, and effectively solves the low
signal-to-noise inefficiency problem of the direct Gibbs sampler. The new
algorithm is a simple Metropolis-Hastings sampler with a general proposal rule
for the power spectrum, C_l, followed by a particular deterministic rescaling
operation of the sky signal. The acceptance probability for this joint move
depends on the sky map only through the difference of chi-squared between the
original and proposed sky sample, which is close to unity in the low
signal-to-noise regime. The algorithm is completed by alternating this move
with a standard Gibbs move. Together, these two proposals constitute a
computationally efficient algorithm for mapping out the full joint CMB
posterior, both in the high and low signal-to-noise regimes.Comment: Submitted to Ap
Annotation of Heterogenous Media Using OntoMedia
While ontologies exist for the annotation of monomedia, interoperability between these schemes is an important issue. The OntoMedia ontology consists of a generic core, capable of representing a diverse range of media, as well as extension ontologies to focus on specific formats. This paper provides an overview of the OntoMedia ontologies, together with a detailed case study when applied to video, a scripted form, and an associated short story
Formation of Low Threshold Voltage Microlasers
Vertical cavity surface emitting lasers (VCSELs) with threshold voltages of 1.7V have been fabricated. The resistance-area product in these new vertical cavity lasers is comparable to that of edge-emitting lasers, and threshold currents as low as 3 mA have been measured. Molecular beam epitaxy was used to grow n-type mirrors, a quantum well active region, and a heavily Be-doped p-contact. After contact definition and alloying, passive high-reflectivity mirrors were deposited by reactive sputter deposition of SiO2/Si3N4 to complete the laser cavity
Global coverage of cetacean line-transect surveys : status quo, data gaps and future challenges
Knowledge of abundance, trends and distribution of cetacean populations is needed to inform marine conservation efforts, ecosystem models and spatial planning. We compiled a geo-spatial database of published data on cetacean abundance from dedicated visual line-transect surveys and encoded >1100 abundance estimates for 47 species from 430 surveys conducted worldwide from 1975-2005. Our subsequent analyses revealed large spatial, temporal and taxonomic variability and gaps in survey coverage. With the exception of Antarctic waters, survey coverage was biased toward the northern hemisphere, especially US and northern European waters. Overall, <25% of the worldâs ocean surface was surveyed and only 6% had been covered frequently enough (⼠5 times) to allow trend estimation. Almost half the global survey effort, defined as total area (km2) covered by all survey study areas across time, was concentrated in the Eastern Tropical Pacific (ETP). Neither the number of surveys conducted nor the survey effort had increased in recent years. Across species, an average of 10% of a speciesâ predicted range had been covered by at least one survey, but there was considerable variation among species. With the exception of three delphinid species, <1% of all speciesâ ranges had been covered frequently enough for trend analysis. We use a data-rich species, sperm whale, as an example to illustrate the challenges of using available data from line-transect surveys for the detection of trends or for spatial planning. Finally, we propose and contrast several field and analytical methods to fill in data gaps to improve future cetacean conservation management efforts.Publisher PDFPeer reviewe
Understanding prejudice and discrimination : heterosexuals' motivations for engaging in homonegativity directed toward gay men
To date, little research has documented the prevalence of anti-gay behaviours on Canadian university campuses or directly explored heterosexual menâs and womenâs self-reported reasons for holding negative attitudes toward gay men and engaging in anti-gay behaviours. Consequently, the purpose of the current study was to: (1) assess the prevalence of anti-gay attitudes and behaviours on a Canadian university campus using the Attitudes Toward Gay Men Scale (ATG) and the Self-Report Behaviour Scale â Revised (SBS-R); (2) describe heterosexual menâs and womenâs lived experiences as perpetrators of homonegativity; and (3) explore how heterosexuals find meaning in their homonegativity within personal and social contexts. A mixed-methods approach was used wherein a quantitative questionnaire was administered to 286 university students in the first phase of the study. The majority of the participants scored below the midpoint of the ATG and they most often reported engaging in subtle behaviours directed toward gay men. In the second, qualitative phase of the study, open-ended interviews were conducted with eight individuals (four men and four women) who held negative attitudes toward gay men and had engaged in anti-gay behaviours. The interviews were analyzed using Interpretative Phenomenological Analysis. The participantsâ lived experiences of homonegativity were primarily characterized by their feelings of discomfort upon observing gay men display affection and their perceptions that gay men are feminine. For the most part, participants used their religious beliefs, negative affective reactions toward homosexuality, and their beliefs that homosexuality is wrong and unnatural to understand their homonegativity. Further, the participants indicated that they had only engaged in subtle anti-gay behaviours, such as joke-telling, social distancing, or avoidance. Many of the participants were concerned about being perceived as prejudiced and, consequently, monitored the behaviours they directed toward gay men. Limitations of the study and directions for future research concerning anti-gay behaviours are also presented
CMB likelihood approximation by a Gaussianized Blackwell-Rao estimator
We introduce a new CMB temperature likelihood approximation called the
Gaussianized Blackwell-Rao (GBR) estimator. This estimator is derived by
transforming the observed marginal power spectrum distributions obtained by the
CMB Gibbs sampler into standard univariate Gaussians, and then approximate
their joint transformed distribution by a multivariate Gaussian. The method is
exact for full-sky coverage and uniform noise, and an excellent approximation
for sky cuts and scanning patterns relevant for modern satellite experiments
such as WMAP and Planck. A single evaluation of this estimator between l=2 and
200 takes ~0.2 CPU milliseconds, while for comparison, a single pixel space
likelihood evaluation between l=2 and 30 for a map with ~2500 pixels requires
~20 seconds. We apply this tool to the 5-year WMAP temperature data, and
re-estimate the angular temperature power spectrum, , and likelihood,
L(C_l), for l<=200, and derive new cosmological parameters for the standard
six-parameter LambdaCDM model. Our spectrum is in excellent agreement with the
official WMAP spectrum, but we find slight differences in the derived
cosmological parameters. Most importantly, the spectral index of scalar
perturbations is n_s=0.973 +/- 0.014, 1.9 sigma away from unity and 0.6 sigma
higher than the official WMAP result, n_s = 0.965 +/- 0.014. This suggests that
an exact likelihood treatment is required to higher l's than previously
believed, reinforcing and extending our conclusions from the 3-year WMAP
analysis. In that case, we found that the sub-optimal likelihood approximation
adopted between l=12 and 30 by the WMAP team biased n_s low by 0.4 sigma, while
here we find that the same approximation between l=30 and 200 introduces a bias
of 0.6 sigma in n_s.Comment: 10 pages, 7 figures, submitted to Ap
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