Dynamic assessment of children with language impairments: A pilot study

This article describes the construction of a procedure for dynamic assessment of the expressive grammar of children already identified with language impairments. Few instruments exist for the dynamic assessment of language, and those that have been developed have been largely used to successfully differentiate language impaired from culturally different or typically developing populations. The emphasis in this study was on eliciting clinically useful information that may be used to inform intervention for children with specific language impairment (SLI). The method was piloted on three children with specific language impairments.The test—train—retest format made use of standardized administration of the CELF-3 (UK) before and after a designated training protocol. The training procedure required the children to formulate sentences from randomly presented words, assisted by mediation from the assessor. Results showed that the task used was valuable and appropriate for use as a dynamic measure, and elicited differentiated amounts of change in the children in response to the mediated training phase. Pre-test—post-test results were inconclusive, however, and the frameworks for summarizing information could benefit from revision

Application of small punch creep testing to a thermally sprayed CoNiCrAlY bond coat

High velocity oxy-fuel thermal spraying was used to prepare free-standing CoNiCrAlY (Co–31.7% Ni–20.8% Cr–8.1% Al–0.5% Y (wt%)) bond coat alloy samples approximately 0.5 mm thick. Creep tests were conducted at 750 °C on these samples using a small punch (SP) creep test method. The samples were characterised before and after creep testing using scanning electron microscopy with electron backscatter diffraction (EBSD). EBSD revealed a two phase fcc γ-Ni and bcc B2 β-NiAl microstructure with grain sizes ~1–2 μm for both phases, which did not change significantly following testing. The constant temperature SP test data were characterised by a minimum creep strain rate, View the MathML source, and a total time to failure, tf, at different applied stresses. The data are fitted to conventional power law equations with a stress exponent for creep close to 8 in the Norton power law and between 7 and 10 in the Monkman–Grant creep rupture law. Creep rupture was predominantly due to creep cavitation voids nucleating at both the γ–β interphase boundaries and the γ–γ grain boundaries leading to final failure by void linkage. However, rupture life was influenced by the quantity of oxide entrained in the coating during the spray deposition process

Atomic excitation during recollision-free ultrafast multi-electron tunnel ionization

Modern intense ultrafast pulsed lasers generate an electric field of sufficient strength to permit tunnel ionization of the valence electrons in atoms. This process is usually treated as a rapid succession of isolated events, in which the states of the remaining electrons are neglected. Such electronic interactions are predicted to be weak, the exception being recollision excitation and ionization caused by linearly-polarized radiation. In contrast, it has recently been suggested that intense field ionization may be accompanied by a two-stage `shake-up' reaction. Here we report a unique combination of experimental techniques that enables us to accurately measure the tunnel ionization probability for argon exposed to 50 femtosecond laser pulses. Most significantly for the current study, this measurement is independent of the optical focal geometry, equivalent to a homogenous electric field. Furthermore, circularly-polarized radiation negates recollision. The present measurements indicate that tunnel ionization results in simultaneous excitation of one or more remaining electrons through shake-up. From an atomic physics standpoint, it may be possible to induce ionization from specific states, and will influence the development of coherent attosecond XUV radiation sources. Such pulses have vital scientific and economic potential in areas such as high-resolution imaging of in-vivo cells and nanoscale XUV lithography.Comment: 17 pages, 4 figures, original format as accepted by Nature Physic

CD133 in brain tumor: the prognostic factor

CD133 has been shown to be an important stem cell factor that promotes glioma progression. However, the mechanism for CD133-mediated glioma progression has yet to be fully elucidated. In this study, we found that CD133 mRNA expression was a prognostic marker in three independent glioma patient cohorts, corroborating a putative role for CD133 in glioma progression. Importantly, we found that CD133 expression in glioma was highly correlated with the expression of HOX gene stem cell factors (HOXA5, HOXA7, HOXA10, HOXC4 and HOXC6). The expression of these HOX genes individually was significantly associated with survival. Interestingly, the prognostic significance of CD133 was dependent on the expression level of HOX genes, and vice versa. CD133 (p = 0.021) and HOXA7 (p = 0.001) were independent prognostic markers when the three glioma patient cohorts were combined (n = 231). Our results suggest that HOX genes may play a more important role in progression of glioma when CD133 expression is low. Furthermore, we showed that low-level expression of LIM2 in CD133-high glioma was associated with poorer survival, suggesting that LIM2 could be a therapeutic target for glioma expressing a high level of CD133. Connectivity mapping identified vinblastine and vincristine as agents that could reverse the CD133/HOX genes/LIM2-signature, and we confirmed this by in vitro analysis in glioma cell lines, demonstrating that CD133 and HOX genes were co-expressed and could be downregulated by vincristine. In conclusion, our data show that CD133 and HOX genes are important prognostic markers in glioma and shed light on possible treatment strategies for glioma expressing a high level of CD133

Quality of life and illness perception in working and sick-listed chronic RSI patients

OBJECTIVE: To study differences between working and sick-listed chronic repetitive strain injury (RSI) patients in the Netherlands with respect to indices of quality of life and illness perception. METHODS: In a cross-sectional design, one questionnaire was sent to all 3,250 members of the national RSI patient association. For descriptive purposes, demographics, work status and complaint-related variables such as severity, type, duration, and extent of complaints were asked for. Indices of quality of life were assessed through seven SF-36 subscales (physical (role) functioning, emotional role functioning, social functioning, pain, mental health and vitality). A work-ability estimate and VAS scales were used to assess complaint-related decrease in quality of life. Illness perception was assessed through the brief illness perception questionnaire (IPQ-B). Working patients and sick-listed patients were identified. Tests between the two independent groups were performed and P-values < 0.01 were considered significant. RESULTS: Data from 1,121 questionnaires were used. Two-thirds of the respondents worked and one-third were sick-listed. Average duration of complaints was over 5 years in both groups. The sick-listed patients reported significantly more severe and extensive complaints than did the working patients. In addition, sick-listed patients reported significantly poorer mental health, physical (role) functioning, emotional role functioning, pain, vitality, and work-ability. With respect to illness perception, both groups showed the same concerns about their complaints, but sick-listed patients had significantly more distorted perceptions in their emotional response, identity, treatment control, personal control, timeline, and life consequences. Complaint-related decrease in quality of life was 31% in the working patients and 49% in the sick-listed patients. CONCLUSION: The study found a greater number and severe complaints among sick-listed chronic RSI patients and a considerably decreased quality of life because of their complaints. These findings may allow for a better treatment focus in the futur

Auditory presentation and synchronization in Adobe Flash and HTML5/JavaScript Web experiments

Substantial recent research has examined the accuracy of presentation durations and response time measurements for visually presented stimuli in Web-based experiments, with a general conclusion that accuracy is acceptable for most kinds of experiments. However, many areas of behavioral research use auditory stimuli instead of, or in addition to, visual stimuli. Much less is known about auditory accuracy using standard Web-based testing procedures. We used a millisecond-accurate Black Box Toolkit to measure the actual durations of auditory stimuli and the synchronization of auditory and visual presentation onsets. We examined the distribution of timings for 100 presentations of auditory and visual stimuli across two computers with difference specs, three commonly used browsers, and code written in either Adobe Flash or JavaScript. We also examined different coding options for attempting to synchronize the auditory and visual onsets. Overall, we found that auditory durations were very consistent, but that the lags between visual and auditory onsets varied substantially across browsers and computer systems

The cost-effectiveness of the RSI QuickScan intervention programme for computer workers: Results of an economic evaluation alongside a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>The costs of arm, shoulder and neck symptoms are high. In order to decrease these costs employers implement interventions aimed at reducing these symptoms. One frequently used intervention is the RSI QuickScan intervention programme. It establishes a risk profile of the target population and subsequently advises interventions following a decision tree based on that risk profile. The purpose of this study was to perform an economic evaluation, from both the societal and companies' perspective, of the RSI QuickScan intervention programme for computer workers. In this study, effectiveness was defined at three levels: exposure to risk factors, prevalence of arm, shoulder and neck symptoms, and days of sick leave.</p> <p>Methods</p> <p>The economic evaluation was conducted alongside a randomised controlled trial (RCT). Participating computer workers from 7 companies (N = 638) were assigned to either the intervention group (N = 320) or the usual care group (N = 318) by means of cluster randomisation (N = 50). The intervention consisted of a tailor-made programme, based on a previously established risk profile. At baseline, 6 and 12 month follow-up, the participants completed the RSI QuickScan questionnaire. Analyses to estimate the effect of the intervention were done according to the intention-to-treat principle. To compare costs between groups, confidence intervals for cost differences were computed by bias-corrected and accelerated bootstrapping.</p> <p>Results</p> <p>The mean intervention costs, paid by the employer, were 59 euro per participant in the intervention and 28 euro in the usual care group. Mean total health care and non-health care costs per participant were 108 euro in both groups. As to the cost-effectiveness, improvement in received information on healthy computer use as well as in their work posture and movement was observed at higher costs. With regard to the other risk factors, symptoms and sick leave, only small and non-significant effects were found.</p> <p>Conclusions</p> <p>In this study, the RSI QuickScan intervention programme did not prove to be cost-effective from the both the societal and companies' perspective and, therefore, this study does not provide a financial reason for implementing this intervention. However, with a relatively small investment, the programme did increase the number of workers who received information on healthy computer use and improved their work posture and movement.</p> <p>Trial registration</p> <p>Trial registration number: NTR1117</p

The continuum of spreading depolarizations in acute cortical lesion development: Examining Leão's legacy.

A modern understanding of how cerebral cortical lesions develop after acute brain injury is based on Aristides Leão's historic discoveries of spreading depression and asphyxial/anoxic depolarization. Treated as separate entities for decades, we now appreciate that these events define a continuum of spreading mass depolarizations, a concept that is central to understanding their pathologic effects. Within minutes of acute severe ischemia, the onset of persistent depolarization triggers the breakdown of ion homeostasis and development of cytotoxic edema. These persistent changes are diagnosed as diffusion restriction in magnetic resonance imaging and define the ischemic core. In delayed lesion growth, transient spreading depolarizations arise spontaneously in the ischemic penumbra and induce further persistent depolarization and excitotoxic damage, progressively expanding the ischemic core. The causal role of these waves in lesion development has been proven by real-time monitoring of electrophysiology, blood flow, and cytotoxic edema. The spreading depolarization continuum further applies to other models of acute cortical lesions, suggesting that it is a universal principle of cortical lesion development. These pathophysiologic concepts establish a working hypothesis for translation to human disease, where complex patterns of depolarizations are observed in acute brain injury and appear to mediate and signal ongoing secondary damage

Incidence and prevalence of upper-extremity musculoskeletal disorders. A systematic appraisal of the literature

BACKGROUND: A systematic appraisal of the worldwide incidence and prevalence rates of UEDs available in scientific literature was executed to gauge the range of these estimates in various countries and to determine whether the rates are increasing in time. METHODS: Studies that recruited at least 500 people, collected data by using questionnaires, interviews and/or physical examinations, and reported incidence or prevalence rates of the whole upper-extremity including neck, were included. RESULTS: No studies were found with regard to the incidence of UEDs and 13 studies that reported prevalence rates of UEDs were included. The point prevalence ranged from 1.6–53%; the 12-months prevalence ranged from 2.3–41%. One study reported on the lifetime prevalence (29%). We did not find evidence of a clear increasing or decreasing pattern over time. The case definitions for UEDs used in the studies, differed enormously. Therefore, it was not possible to pool the data. CONCLUSION: There are substantial differences in reported prevalence rates on UEDs. Main reason for this is the absence of a universally accepted way of labelling or defining UEDs. If we want to make progress in this field, the first requirement is to agree on unambiguous terminology and classification of EUDs