991 research outputs found

    Learning environments matter: Identifying influences on the motivation to learn science

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    In the light of the poor academic achievement in science by secondary school students in South Africa, students’ motivation for science learning should be enhanced. It is argued that this can only be achieved with insight into which motivational factors to target, with due consideration of the diversity in schools. The study therefore explored the impact of six motivational factors for science learning in a sample of 380 Grade Nine boys and girls from three racial groups, in both public and independent schools. The students completed the Student Motivation for Science Learning questionnaire. Significant differences were identified between different groups and school types. The study is important for identifying the key role of achievement goals, science learning values and science self-efficacies. The main finding emphasises the significant role played by science teachers in motivating students for science in terms of the learning environments that they create. This has important implications for future research, aimed at a better understanding of these environments. Such insights are needed to promote scientific literacy among the school students, and so contribute to the improvement of science achievement in South Africa.Keywords: achievement goals; gender and racial group influences on motivation to learn science; influence of school; learning environment; mastery goals; motivation to learn science; science learning values; self-efficac

    De casus Tiel-Passewaaij

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    Roymans, N.G.A.M. [Promotor]Derks, A.M.J. [Copromotor

    Macular Pigment Distribution as Prognostic Marker for Disease Progression in Macular Telangiectasia Type 2

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    PURPOSE To evaluate macular pigment distribution pattern as a prognostic marker for disease progression in patients with macular telangiectasia type 2 (MacTel). DESIGN Retrospective cohort study. METHODS In this single-center study, 90 eyes of 47 patients were analyzed. Macular pigment optical density (MPOD) was measured with dual-wavelength fundus autofluorescence. Eyes were graded into MPOD distribution classes 1 to 3 with increasing loss of macular pigment and grading was performed masked by 2 independent graders. Best-corrected visual acuity, reading acuity, total scotoma size in fundus-controlled perimetry (microperimetry), and break of the ellipsoid zone (EZ) in optical coherence tomography (en face measurement) were defined as functional and morphologic outcome parameters and evaluated at baseline and after 60 months. RESULTS After a mean review period of 59.6 months (±standard deviation 5.2 months), no change between MPOD classes was observed compared to baseline. Morphologic and functional deficits were limited to the area of MPOD loss. At last follow-up, a significant mean decrease of visual acuity and reading acuity as well as a significant mean increase of scotoma size and EZ break were observed in eyes assigned to MPOD classes 2 and 3, while outcome parameters remained stable in eyes of class 1. CONCLUSIONS The results indicate that MPOD and its distribution may serve as a prognostic marker for disease progression and functional impairment in patients with MacTel

    Identifying Advantages and Disadvantages of Variable Rate Irrigation – An Updated Review

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    Variable rate irrigation (VRI) sprinklers on mechanical move irrigation systems (center pivot or lateral move) have been commercially available since 2004. Although the number of VRI, zone or individual sprinkler, systems adopted to date is lower than expected there is a continued interest to harness this technology, especially when climate variability, regulatory nutrient management, water conservation policies, and declining water for agriculture compound the challenges involved for irrigated crop production. This article reviews the potential advantages and potential disadvantages of VRI technology for moving sprinklers, provides updated examples on such aspects, suggests a protocol for designing and implementing VRI technology and reports on the recent advancements. The advantages of VRI technology are demonstrated in the areas of agronomic improvement, greater economic returns, environmental protection and risk management, while the main drawbacks to VRI technology include the complexity to successfully implement the technology and the lack of evidence that it assures better performance in net profit or water savings. Although advances have been made in VRI technologies, its penetration into the market will continue to depend on tangible and perceived benefits by producers

    Stereoscopic Vision in Macular Telangiectasia Type 2

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    PURPOSE: To investigate stereoscopic vision in patients with macular telangiectasia type 2 and correlate a paracentral sensitivity loss to reduced stereoscopic function. METHODS: In a prospective single-center study, 50 patients with macular telangiectasia type 2 and 25 age-matched controls were investigated. Stereoscopic function was evaluated with Lang I, Titmus and TNO-test. Sensitivity of the central 16° was tested using fundus-controlled perimetry (microperimetry). Functional loss was quantified as depth, size and localization of scotomata. RESULTS: Both Titmus and TNO-test revealed significantly reduced stereoscopic vision in patients compared to controls (both, p<0.0001). This applied even to patients with only relative or monocular paracentral scotomata. A strong correlation was observed for reduced stereoscopic vision with horizontal scotoma size and with the distance of scotomata from the foveal center. CONCLUSIONS: The results indicate that stereoscopic vision is impaired early in patients with MacTel type 2. A paracentral sensitivity loss, even if mild and limited to one eye, may considerably interfere with stereoscopic function despite normal visual acuity. Projection of paracentral scotomata within the patient`s central visual field plays an important role in stereoscopic vision and should be considered when interpreting stereoscopic test results

    Quantification of Retinal and Choriocapillaris Perfusion in Different Stages of Macular Telangiectasia Type 2

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    Purpose: To quantify the retinal and choriocapillaris perfusion in different disease stages of macular telangiectasia type 2 (MacTel) using optical coherence tomography-angiography (OCT-A). / Methods: We examined 76 eyes of 76 patients and 24 eyes of 24 age-related controls. Participants underwent multimodal imaging, including OCT and OCT-A. Patients' eyes were divided into three groups considering predefined criteria from funduscopy, OCT, and fluorescein angiography, thus reflecting the disease severity (“early,” “advanced,” and “neovascular”). Quantitative analyses of vessel density (VD), skeleton density (SD), and fractal dimension (FD) were conducted in the superficial and deep retinal plexus and in the avascular layer. The choriocapillaris was analyzed for mean signal intensity and percentage of nondetectable perfused choriocapillaris-area (PNPA). / Results: The deep retinal plexus showed a progressive decrease of mean VD, SD, and FD in the temporal parafovea in all disease stages. In the superficial layer, VD, SD, and FD were significantly decreased in the temporal parafovea of advanced and neovascular stages, while these parameters did not differ from controls in early stages. In MacTel, signals of blood flow were also detectable at the level of the avascular layer and showed a significant increase with disease progression. The choriocapillaris in MacTel showed a significant increase of mean PNPA and a decrease of mean signal intensity in comparison to controls. These findings were consistent in all disease stages. / Conclusions: Quantitative OCT-A data show a progressive rarefication of the retinal microvasculature in MacTel. We propose an altered choriocapillaris perfusion as a possibly early alteration of the disease

    Providing care for older adults in the Emergency Department: expert clinical recommendations from the European Task Force on Geriatric Emergency Medicine

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    Cures agudes; Medicina d'urgències; GeriatriaCuidados agudos; Medicina de urgencias; GeriatríaAcute care; Emergency medicine; GeriatricsPurpose: Despite the rapidly expanding knowledge in the field of Geriatric Emergency Medicine in Europe, widespread implementation of change is still lacking. Many opportunities in everyday clinical care are missed to improve care for this susceptible and growing patient group. The aim was to develop expert clinical recommendations on Geriatric Emergency Medicine to be disseminated across Europe. Methods: A group of multi-disciplinary experts in the field of Geriatric Emergency Medicine in Europe was assembled. Using a modified Delphi procedure, a prioritized list of topics related to Geriatric Emergency Medicine was created. Next, a multi-disciplinary group of nurses, geriatricians and emergency physicians performed a review of recent guidelines and literature to create recommendations. These recommendations were voted upon by a group of experts and placed on visually attractive posters. The expert group identified the following eight subject areas to develop expert recommendations on: Comprehensive Geriatric Assessment in the Emergency Department (ED), age/frailty adjusted risk stratification, delirium and cognitive impairment, medication reviews in the ED for older adults, family involvement, ED environment, silver trauma, end of life care in the acute setting. Results: Eight posters with expert clinical recommendations on the most important topics in Geriatric Emergency Medicine are now available through https://posters.geriemeurope.eu/ . Conclusion: Expert clinical recommendations for Geriatric Emergency Medicine may help to improve care for older patients in the Emergency Department and are ready for dissemination across Europe

    Regional variation in the pronunciation of /s/ in the Dutch language area

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    Theoretical and Experimental Linguistic

    Alcohol Policies and Alcoholic Cirrhosis Mortality in the United States

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    Introduction Stronger alcohol policies predict decreased alcohol consumption and binge drinking in the United States. We examined the relation- ship between the strength of states’ alcohol policies and alcoholic cirrhosis mortality rates. Methods We used the Alcohol Policy Scale (APS), a validated assessment of policies of the 50 US states and Washington DC, to quantify the efficacy and implementation of 29 policies. State APS scores (the- oretical range, 0–100) for each year from 1999 through 2008 were compared with age-adjusted alcoholic cirrhosis death rates that oc- curred 3 years later. We used Poisson regression accounting for state-level clustering and adjusting for race/ethnicity, college edu- cation, insurance status, household income, religiosity, policing rates, and urbanization. Results Age-adjusted alcoholic cirrhosis mortality rates varied signific- antly across states; they were highest among males, among resid- ents in states in the West census region, and in states with a high proportion of American Indians/Alaska Natives (AI/ANs). Higher APS scores were associated with lower mortality rates among fe- males (adjusted incidence rate ratio [IRR], 0.91 per 10-point in- crease in APS score; 95% confidence interval [95% CI], 0.84–0.99) but not among males (adjusted IRR, 0.97; 95% CI, 0.90–1.04). Among non-AI/AN decedents, higher APS scores were also associated with lower alcoholic cirrhosis mortality rates among both sexes combined (adjusted IRR, 0.89; 95% CI, 0.82–0.97). Policies were more strongly associated with lower mortality rates among those living in the Northeast and West census regions than in other regions. Conclusions Stronger alcohol policy environments are associated with lower al- coholic cirrhosis mortality rates. Future studies should identify un- derlying reasons for racial/ethnic and regional differences in this relationship

    New HARPS and FEROS observations of GJ1046

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    In this paper we present new precise Doppler data of GJ1046 taken between November 2005 and July 2018 with the HARPS and the FEROS high-resolution spectographs. In addition, we provide a new stellar mass estimate of GJ1046 and we update the orbital parameters of the GJ1046 system. These new data and analysis could be used together with the GAIA epoch astrometry, when available, for braking the sini\sin i degeneracy and revealing the true mass of the GJ1046 system.Comment: 2 pages, 1 figure, 1 table with RV data (available only in the Astro-PH version of the paper), Accepted by RNAA
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