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31.
P Gennis L Miller EJ Gallagher J Giglio W Carter N Nathanson 《Canadian Metallurgical Quarterly》1996,3(6):568-573
Thirty-five male patients, aged 34-79 yr, with definite rheumatoid arthritis (RA) were recruited from out-patient clinics and randomized to receive monthly injections of testosterone enanthate 250 mg or placebo as an adjunct therapy for 9 months. Endpoints included disease activity parameters and bone mineral density (BMD). At baseline, there were negative correlations between the ESR and serum testosterone (r = -0.42, P < 0.01) and BMD (hip, r = -0.65, P < 0.01). A total of 29.6% of all patients had at least one vertebral fracture, most having multiple fractures. Back pain, however, was not more prevalent in fracture patients (55% vs 50%). Disease activity was significantly higher in the fracture group (joint score P < 0.05, rheumatoid factor P < 0.01). Thirty patients completed the trial, 15 receiving testosterone and 15 receiving placebo. There were significant rises in serum testosterone, dihydrotestosterone and oestradiol in the treatment group. There was no significant effect of treatment on disease activity overall, five patients receiving testosterone underwent a "flare'. Differences in mean BMD following testosterone or placebo were non-significant (spine: +1.2% vs -1.1%; femur: -0.3% vs +0.3%). There was no suggestion of a positive effect of testosterone on disease activity in men with RA. 相似文献
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One of congress’ goals for 2007 was for 80% of all tax and informational returns to be filed electronically. However, to date
that lofty goal has fallen well short. This research proposes a model of e-filing adoption. To test the model a survey is
administered to 260 participants. The instrument assesses citizen perceptions of trust, risk and optimism bias. Structural
equation modeling is used to evaluate the relationships between these three concepts and intention to use. The results indicate
that trust of the Internet, trust of the e-filer, perceived risk and optimism bias all have an impact on intention to use
e-filing. Implications for practice and research are discussed. 相似文献
34.
Christian Collberg Andrew Huntwork Edward Carter Gregg Townsend Michael Stepp 《Information and Software Technology》2009,51(1):56-67
This paper presents an implementation of the watermarking method proposed by Venkatesan et al. in their paper [R. Venkatesan, V. Vazirani, S. Sinha, A graph theoretic approach to software watermarking, in: Fourth International Information Hiding Workshop, Pittsburgh, PA, 2001]. An executable program is marked by the addition of code for which the topology of the control-flow graph encodes a watermark. We discuss issues that were identified during construction of an actual implementation that operates on Java bytecode. We present two algorithms for splitting a watermark number into a redundant set of pieces and an algorithm for turning a watermark number into a control-flow graph. We measure the size and time overhead of watermarking, and evaluate the algorithm against a variety of attacks. 相似文献
35.
Gregory D. Larosiliere Lemuria D. Carter 《Journal of Computer Information Systems》2016,56(4):271-279
E-Government diffusion is of interest to both researchers and practitioners. The purpose of this study is to investigate electronic government maturity and its determinants. We use the Fit-Viability Framework to assess e-Government Maturity in diverse countries. We empirically test the impact of task-technology fit (TTF) and viability on e-government maturity at the country level. The results of partial least squares (PLS) analysis indicate that TTF characteristics along with a country’s viable resources and level of e-government development have a significant impact on e-government maturity. Implications for research and practice are discussed. 相似文献
36.
Jason M. Harley Cassia K. Carter Niki Papaionnou François Bouchet Ronald S. Landis Roger Azevedo Lana Karabachian 《User Modeling and User-Adapted Interaction》2016,26(2-3):177-219
The current study examined the relationships between learners’ (\(N = 123\)) personality traits, the emotions they typically experience while studying (trait studying emotions), and the emotions they reported experiencing as a result of interacting with four pedagogical agents (agent-directed emotions) in MetaTutor, an advanced multi-agent learning environment. Overall, significant relationships between a subset of trait emotions (trait anger, trait anxiety) and personality traits (agreeableness, conscientiousness, and neuroticism) were found for four agent-directed emotions (enjoyment, pride, boredom, and neutral) though the relationships differed between pedagogical agents. These results demonstrate that some trait emotions and personality traits can be used to predict learners’ emotions directed toward specific pedagogical agents (with different roles). Results provide suggestions for adapting pedagogical agents to support learners’ (with certain characteristics; e.g., high in neuroticism or agreeableness) experience of adaptive emotions (e.g., enjoyment) and minimize their experience on non-adaptive emotions (e.g., boredom). Such an approach presents a scalable and easily implementable method for creating emotionally-adaptive, agent-based learning environments, and improving learner-pedagogical agent interactions in order to support learning. 相似文献
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The beam radius along a focused, unapertured Gaussian beam was measured and used to calculate the dependence of the geometrical Fresnel number on the effective Fresnel number of the beam as it emerged from the focusing lens. The resulting data clearly demonstrate a focal shift away from the focal plane given by geometrical optics. The data agree very well with a theory due to Carter. This theory indicates that a significant focal shift occurs in these beams if the focusing lens is placed within the near field of the focal plane. 相似文献
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Nanoparticles and nanoparticle-based devices are of interest in numerous industrial applications due to their unique and often
advantageous properties. However, a major obstacle to the full exploitation of nanoscale materials is the lack of production
processes that yield specific materials reproducibly. A fundamental understanding of nanoparticle formation in candidate production
systems is critical to achieving both product specificity and uniformity. The present work uses observations from transmission
electron microscopy to elucidate the formation processes occurring for silicon and titanium nanoparticles produced from a
thermal plasma process. The structure, chemistry, and defect morphology of the nanoparticles are consistent with a rapid cooling
and crystallization from a liquid droplet. The observation of surface faceting on some nanoparticles suggests a transition
between different crystalline growth regimes. 相似文献