257 research outputs found
Salient features of contextual interference and knowledge of results
The current study investigated the relationship between the contextual interference effect and knowledge of results manipulations. Specifically, three variations of a relative timing task were presented in either a blocked or random schedule, and participants were either required to error estimate or given no instruction concerning estimation. A 2 (Acquisition Context) x 2 (Error Estimation Frequency) ANOVA was used to analyze absolute error (AE), variable error (VE) and a relative timing measure (AE(prop.)). The main effects that there was a blocked advantage during retention. In addition, a 100% estimation advantage existed for AE and VE, but was not present for AE(prop.). These results indicate that the relative difficulty of the task may have been too high to produce a random group advantage and that error estimation of relative timing may have been too much for the participant to process. In conclusion, it was proposed that the two factors may interact, but relative difficulty of the task needs to be taken into account
REM4j - A framework for measuring the reverse engineering capability of UML CASE tools
Reverse Engineering is becoming increasingly important
in the software development world today as many organizations
are battling to understand and maintain old legacy
systems. Today’s software engineers have inherited these
legacy systems which they may know little about yet have to
maintain, extend and improve. Currently there is no framework
or strategy that an organisation can use to determine
which UML CASE tool to use. This paper sets down such a
framework, to allow organisations to base their tool choice
on this reliable framework.
We present the REM4j tool, an automated tool, for
benchmarking UML CASE tools, we then use REM4j to
carry out one such evaluation with eleven UML CASE tools.
This framework allows us to reach a conclusion as to which
is the most accurate and reliable UML CASE tool
Development and Implementation of an Integrated Science Course for Elementary Education Majors
Currently the scientific community is trying to increase the general population’s knowledge of science. These efforts stem from the fact that the citizenry needs a better understanding of scientific knowledge to make informed decisions on many issues of current concern. The problem of scientific illiteracy begins in grade school and can be traced to inadequate exposure to science and scientific thinking during the preparation of K–8 teachers. Typically preservice elementary teachers are required to take only one or two disconnected science courses to obtain their teaching certificates. Also, introductory science courses are often large and impersonal, with the result that while students pass the courses, they may learn very little and retain even less
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Effector memory differentiation increases detection of replication-competent HIV-l in resting CD4+ T cells from virally suppressed individuals.
Studies have demonstrated that intensive ART alone is not capable of eradicating HIV-1, as the virus rebounds within a few weeks upon treatment interruption. Viral rebound may be induced from several cellular subsets; however, the majority of proviral DNA has been found in antigen experienced resting CD4+ T cells. To achieve a cure for HIV-1, eradication strategies depend upon both understanding mechanisms that drive HIV-1 persistence as well as sensitive assays to measure the frequency of infected cells after therapeutic interventions. Assays such as the quantitative viral outgrowth assay (QVOA) measure HIV-1 persistence during ART by ex vivo activation of resting CD4+ T cells to induce latency reversal; however, recent studies have shown that only a fraction of replication-competent viruses are inducible by primary mitogen stimulation. Previous studies have shown a correlation between the acquisition of effector memory phenotype and HIV-1 latency reversal in quiescent CD4+ T cell subsets that harbor the reservoir. Here, we apply our mechanistic understanding that differentiation into effector memory CD4+ T cells more effectively promotes HIV-1 latency reversal to significantly improve proviral measurements in the QVOA, termed differentiation QVOA (dQVOA), which reveals a significantly higher frequency of the inducible HIV-1 replication-competent reservoir in resting CD4+ T cells
Endocrine responses to overreaching before and after 1 year of weightlifting
This is the publisher's version, also found at http://ehis.ebscohost.com/ehost/external?sid=c58e4c93-cdad-411e-8971-ff871436da4b%40sessionmgr14&vid=3&hid=1
Prostate cancer assessment using MR elastography of fresh prostatectomy specimens at 9.4 T
Purpose: Despite its success in the assessment of prostate cancer (PCa), in vivo multiparametric MRI has limitations such as interobserver variability and low specificity. Several MRI methods, among them MR elastography, are currently being discussed as candidates for supplementing conventional multiparametric MRI. This study aims to investigate the detection of PCa in fresh ex vivo human prostatectomy specimens using MR elastography.
Methods: Fourteen fresh prostate specimens from men with clinically significant PCa without formalin fixation or prior radiation therapy were examined by MR elastography at 500 Hz immediately after radical prostatectomy in a 9.4T preclinical scanner. Specimens were divided into 12 segments for both calculation of storage modulus (G ' in kilopascals) and pathology (Gleason score) as reference standard. Sensitivity, specificity, and area under the receiver operating characteristic curve were calculated to assess PCa detection.
Results: The mean G ' and SD were as follows: all segments, 8.74 ± 5.26 kPa; healthy segments, 5.44 ± 4.40 kPa; and cancerous segments, 10.84 ± 4.65 kPa. The difference between healthy and cancerous segments was significant with P ≤ .001. Diagnostic performance assessed with the Youden index was as follows: sensitivity, 69%; specificity, 79%; area under the curve, 0.81; and cutoff, 10.67 kPa.
Conclusion: Our results suggest that prostate MR elastography has the potential to improve diagnostic performance of multiparametric MRI, especially regarding its 2 major limitations: interobserver variability and low specificity. Particularly the high value for specificity in PCa detection is a stimulating result and encourages further investigation of this method
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Filtered Rayleigh scattering diagnostic for multi-parameter thermal-fluids measurements : LDRD final report.
Simulation-based life-cycle-engineering and the ASCI program have resulted in models of unprecedented size and fidelity. The validation of these models requires high-resolution, multi-parameter diagnostics. Within the thermal-fluids disciplines, the need for detailed, high-fidelity measurements exceeds the limits of current engineering sciences capabilities and severely tests the state of the art. The focus of this LDRD is the development and application of filtered Rayleigh scattering (FRS) for high-resolution, nonintrusive measurement of gas-phase velocity and temperature. With FRS, the flow is laser-illuminated and Rayleigh scattering from naturally occurring sources is detected through a molecular filter. The filtered transmission may be interpreted to yield point or planar measurements of three-component velocities and/or thermodynamic state. Different experimental configurations may be employed to obtain compromises between spatial resolution, time resolution, and the quantity of simultaneously measured flow variables. In this report, we present the results of a three-year LDRD-funded effort to develop FRS combustion thermometry and Aerosciences velocity measurement systems. The working principles and details of our FRS opto-electronic system are presented in detail. For combustion thermometry we present 2-D, spatially correlated FRS results from nonsooting premixed and diffusion flames and from a sooting premixed flame. The FRS-measured temperatures are accurate to within {+-}50 K (3%) in a premixed CH4-air flame and within {+-}100 K for a vortex-strained diluted CH4-air diffusion flame where the FRS technique is severely tested by large variation in scattering cross section. In the diffusion flame work, FRS has been combined with Raman imaging of the CH4 fuel molecule to correct for the local light scattering properties of the combustion gases. To our knowledge, this is the first extension of FRS to nonpremixed combustion and the first use of joint FRS-Raman imaging. FRS has been applied to a sooting C2H4-air flame and combined with LII to assess the upper sooting limit where FRS may be utilized. The results from this sooting flame show FRS temperatures has potential for quantitative temperature imaging for soot volume fractions of order 0.1 ppm. FRS velocity measurements have been performed in a Mach 3.7 overexpanded nitrogen jet. The FRS results are in good agreement with expected velocities as predicted by inviscid analysis of the jet flowfield. We have constructed a second FRS opto-electronic system for measurements at Sandia's hypersonic wind tunnel. The details of this second FRS system are provided here. This facility is currently being used for velocity characterization of these production hypersonic facilities
Validating Health Impact Assessment: Prediction is difficult (especially about the future)
Health Impact Assessment (HIA) has been recommended as a means of estimating how policies, programmes and projects may impact on public health, and on health inequalities. This paper considers the difference between predicting health impacts, and measuring those impacts. It draws upon a case study of the building of a new hypermarket in a deprived area of Glasgow, which offered an opportunity to reflect on the issue of the predictive validity of HIA, and to consider the difference between potential and actual impacts. We found that the actual impacts of the new hypermarket on diet differed from that which would have been predicted based on previous studies. Furthermore they challenge current received wisdom about the impact of food retail outlets in poorer areas. These results are relevant to the validity of HIA as a process and emphasise the importance of further research on the predictive validity of HIA, which should help improve its value to decision-makers
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