Teachers' acceptance and use of an educational portal

In this study, teachers' acceptance and use of an educational portal is assessed based on data from two sources: usage data (number of logins, downloads, uploads, reactions and pages viewed) and an online acceptance questionnaire. The usage data is extracted on two occasions from the portal's database: at survey completion (T1) and twenty-two months later (T2). Framework for this study is C-TAM-TPB (Combined Technology Acceptance Model and Theory of Planned Behavior). 919 usable responses from teachers are obtained. Based on the observed use data at T1, four types of portal users are distinguished: ‘new’ (N = 37), ‘light’ (N = 641), ‘medium’ (N = 201), and ‘heavy’ (N = 40). Path analyses show that all predictor variables in C-TAM-TPB influence teachers' portal acceptance, but their significance level varies depending on the user type. The strongest predictors of behavioral intention to use the portal are attitude (‘new’) and perceived usefulness (‘light’, ‘medium’ and ‘heavy’), with variance explained ranging from .39 (‘medium’) to .71 (‘heavy’). The observed use data show that the portal is primarily used to search for and download material, rather than for sharing material or information. The use data at T2 show that teachers become more efficient in their search behavior and that the majority of the teachers use the portal more frequently. Guidelines are proposed to policymakers and school boards aiming to introduce a similar technology to teachers.     

Efficacy and onset of action of fluticasone propionate aqueous nasal spray on nasal symptoms, eosinophil count, and mediator release after nasal allergen challenge in patients with seasonal allergic rhinitis

In order to determine if peripheral blood stem cells (PBSC) collected after priming with G-CSF in AML in first complete remission (CR) can be used for autologous transplantation and to evaluate the efficacy of early intensification therapy as in vivo purging, we studied 35 consecutive patients with AML in first CR. After standard induction and consolidation chemotherapy, 24 of them were treated with one (10 patients) or two (14 patients) cycles of high-dose cytarabine plus etoposide prior to PBSC collection. G-CSF was used as the priming agent. Of the 35 patients scheduled for peripheral blood stem cell transplantation (PBSCT), three relapsed before transplantation, and the 32 remaining underwent PBSCT. High-dose therapy consisted of either total body irradiation plus cyclophosphamide or busulphan plus cyclophosphamide. The median number of CD34+ cells infused was 3.24 x 10(6)/kg (range 0.15-14). The median times to reach a PMN count of 0.5 x 10(9)/l and a platelet count of 50 x 10(9)/l were 12 (8-28) and 30 (11-345) days, respectively. There was no transplant-related mortality. Twelve patients relapsed between 2 and 21 months post-PBSCT. With a median follow-up of 28 months, actuarial disease-free survival (DFS) is 52.41 +/- 9% in the intent-to-treat group and 57.4 +/- 9.8% in patients who underwent PBSCT. The probability of DFS is significantly higher for patients who receive early intensification therapy prior to both PBSC collection and PBSCT as compared with patients that do not: 68.8 +/- 10.27% vs 35.5 +/- 12.6%, P = 0.0418. These results indicate the feasibility of PBSCT in AML using G-CSF-mobilized PBSC. The use of intensification treatment as 'purging in vivo' prior both to collection of PBSC and PBSCT significantly reduces the risk of relapse in this group of patients.     

Improving accuracy in detecting acoustic onsets.

In current cognitive psychology, naming latencies are commonly measured by electronic voice keys that detect when sound exceeds a certain amplitude threshold. However, recent research (e.g., K. Rastle & M. H. Davis, 2002) has shown that these devices are particularly inaccurate in precisely detecting acoustic onsets. In this article, the authors discuss the various problems and solutions that have been put forward with respect to this issue and show that classical voice keys may trigger several tens of milliseconds later than acoustic onset. The authors argue that a solution to this problem may come from voice keys that use a combination of analogue and digital noise (nonspeech sound) detection. It is shown that the acoustic onsets detected by such a device are only a few milliseconds delayed and correlate highly (up to .99) with reaction time values obtained by visual waveform inspection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Leaving the third dimension: no measurable evidence for cognitive aftereffects of stereoscopic 3D movies

Stereoscopic 3D (S‐3D) is becoming an increasingly important display technology. Parallel to this, concern about the potential negative effects of exposure to S‐3D movies has been growing. Some manufacturers place disclaimers on their TVs advising people to limit the time they watch S‐3D. However, surprisingly little experimental research has been conducted estimating the genuineness of these concerns. Therefore, an experiment was designed to assess the potential impact of viewing an S‐3D movie on visual, spatial, and general attention performance. To mimic the real‐world experience of watching a movie in the living room, participants (N = 61) watched a full movie in either 2D or S‐3D. Our results do not show evidence for cognitive aftereffects of S‐3D movies. A second experiment (N = 32) that focused on possible aftereffects on visual attention also failed to find reliable effects. We therefore conclude that cognitive functioning is not altered by watching an S‐3D movie, at least not to an extent that is measurable through well‐established cognitive tasks.     

Variability of operator performance in remote-sensing image interpretation: the importance of human and external factors

This study tackles a common, yet underrated problem in remote-sensing image analysis: the fact that human interpretation is highly variable among different operators. Despite current technological advancements, human perception and interpretation are still vital components of the map-making process. Consequently, human errors can considerably bias both mapping and modelling results. In our study, we present a web-based tool to quantify operator variability and to identify the human and external factors affecting this variability. Human operators were given a series of images and were asked to hand-digitize different point, line, and polygon objects. The quantification of performance variability was achieved using both thematic and positional accuracy measures. Subsequently, a series of questions related to demographics, experience, and personality were asked, and the answers were also quantified. Correlation and regression analysis was then used to explain the variability in operator performance. From our study, we conclude that: (1) humans were seldom perfect in visual interpretation; (2) some geographic objects were more complex to accurately digitize than others; (3) there was a high degree of variability among image interpreters when hand-digitizing the same objects; and (4) operator performance was mainly determined by demographic, non-cognitive, and cognitive personality factors, whereas external and technical factors influenced operator performance to a lesser extent. Finally, the results also indicated a gradual decline in performance over time, mimicking classical mental fatigue effects.     

Translation and Associative Priming With Cross-Lingual Pseudohomophones: Evidence for Nonselective Phonological Activation in Bilinguals.

Using a lexical-decision task performed by Dutch-English bilinguals, the author showed that the recognition of visually presented first language (L1; e.g., touw) and second language (L2; e.g., back) targets is facilitated by L2 and L1 masked primes, respectively, which are pseudohomophones (roap and ruch) of the target's translation equivalent (rope and rug). Moreover, recognition of L2 targets (e.g., church) was also facilitated by L1 pseudohomophones (pous) of related words (paus [pope]). Contrastingly, no priming was observed for L1 targets (e.g., been [leg]) and L2 pseudohomophone associative primes (knea). Finally, the author found that an L2 target word (e.g., corner) is facilitated by a more frequent L2 (intralingual) homophone (e.g., hook) of its L1 translation equivalent (hoek). These findings strongly suggest language-independent activation of phonological representations in bilinguals and are compatible with the temporal delay assumption of the bilingual interactive activation plus model (A. Dijkstra & W. Van Heuven, 2002). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Order or disorder? Impaired Hebb learning in dyslexia.

The present study offers an integrative account proposing that dyslexia and its various associated cognitive impairments reflect an underlying deficit in the long-term learning of serial-order information, here operationalized as Hebb repetition learning. In nondyslexic individuals, improved immediate serial recall is typically observed when one particular sequence of items is repeated across an experimental session, a phenomenon known as the Hebb repetition effect. Starting from the critical observation that individuals with dyslexia seem to be selectively impaired in cognitive tasks that involve processing of serial order, the present study is the first to test and confirm the hypothesis that the Hebb repetition effect is affected in dyslexia, even for nonverbal modalities. We present a theoretical framework in which the Hebb repetition effect is assumed to be a laboratory analogue of naturalistic word learning, on the basis of which we argue that dyslexia is characterized by an impairment of serial-order learning that affects language learning and processing. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Assessment of neovascular permeability in a pancreatic tumor model using dynamic contrast-enhanced (DCE) MRI with contrast agents of different molecular weights

Object  

We evaluated the relationship of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)-derived pharmacokinetic parameters and contrast agents with different molecular weights (MW) in a pancreatic tumor mouse model.     

Viewing the Viewers: Viewing Behaviors by Children and Adults During Television Programs and Commercials

Videotapes of in-home television viewing of 50 individuals in five age groups (2-, 5-, 8-, and 12-year-olds, and adults), recorded over a 10-day period, revealed that 46% of time with television was spent in some activity instead of or in addition to looking at the TV. Social interaction was the most common nonviewing activity for all viewers, followed by playing and eating for children and reading for adults. Women were more likely than all other groups to do chores. Nonviewing behaviors occurred most often during programming that attracted less visual attention, particularly ads. Except for 2-year-olds, children's attention dropped during ads to a greater extent than did that of adults. The findings have implications for theories of television use and impact including uses and gratifications, displacement, and formal feature theory.