A method to determine the impact of reduced visual function on nodule detection performance

Purpose: In this study we aim to validate a method to assess the impact of reduced visual function and observer performance concurrently with a nodule detection task. Materials and methods: Three consultant radiologists completed a nodule detection task under three conditions: without visual defocus (0.00 Dioptres; D), and with two different magnitudes of visual defocus ( 1.00 D and 2.00 D). Defocus was applied with lenses and visual function was assessed prior to each image evaluation. Observers evaluated the same cases on each occasion; this comprised of 50 abnormal cases containing 1e4 simulated nodules (5, 8, 10 and 12 mm spherical diameter, 100 HU) placed within a phantom, and 25 normal cases (images containing no nodules). Data was collected under the free-response paradigm and analysed using Rjafroc. A difference in nodule detection performance would be considered significant at p < 0.05. Results: All observers had acceptable visual function prior to beginning the nodule detection task. Visual acuity was reduced to an unacceptable level for two observers when defocussed to 1.00 D and for one observer when defocussed to 2.00 D. Stereoacuity was unacceptable for one observer when defocussed to 2.00 D. Despite unsatisfactory visual function in the presence of defocus we were unable to find a statistically significant difference in nodule detection performance (F(2,4) 1⁄4 3.55, p 1⁄4 0.130). Conclusion: A method to assess visual function and observer performance is proposed. In this pilot evaluation we were unable to detect any difference in nodule detection performance when using lenses to reduce visual function

Variability of fusion vergence measurements in heterophoria

Purpose: The aims of this study were to compare fusional vergence measurements between orthophoria, esophoria, and exophoria, and to determine the strength of correlations between fusional convergence and divergence and angle of deviation. Methods and materials: A cross-sectional study was performed in children with best-corrected visual acuity of 0.0 LogMAR in either eye, compensated heterophoria within 10 prism diopters (PD), full ocular rotations, presence of fusional vergence, and stereopsis (60 seconds of arc or better). Fusional amplitudes were compared between orthophoric and heterophoric children. The fusion reserve ratio was determined as compensating vergence divided by alternating cover test. Results: Five hundred and thirty children (7.66±1.20 years) were recruited to this study. The most common heterophoria was exophoria (n=181, 34.2% for near; n=20, 3.8% for distance). Exophoric children had significant lower mean positive fusional vergences (exophoria-orthophoria: P=0.003; exophoria-esophoria: P=0.035) for near (19.54±5.23 base-out) compared with children with orthophoria (20.48±4.83 base-out) and esophoria (22.27±5.60 base-out). Smaller convergence fusion amplitudes were associated with larger angles of deviation at near (rs=-0.115; P=0.008) and lower fusion reserve ratios were associated with larger angles of deviation at distance (rs=-0.848; P<0.001) and at near (rs=-0.770; P<0.001). Conclusions: Exophoric children have reduced convergence break points when compared with orthophoric and esophoric children. Vergence measurements, taking into consideration the baseline heterophoria, give important information about the ability of the patient to increase their vergence demand and maintain ocular alignment

COVID-19 in Two Children with New-Onset Diabetes: Case Reports

Delayed diagnosis, low socioeconomic status and infection have been associated with diabetic ketoacidosis (DKA) at type 1 diabetes mellitus presentation. A teenager from a low socioeconomic status family, with longstanding weight loss, polyphagia, polyuria, vomiting and abdominal pain, attended the emergency department, also complaining of anosmia and odynophagia. He was diagnosed with COVID-19 and new-onset DKA. The second child had 2 weeks of diabetes symptoms and was admitted with new-onset mild DKA. SARS-CoV-2 RT-PCR test was positive, although asymptomatic. Persistent hyperglycaemia with high insulin requirements was a common feature to both patients. Both cases support that SARS-CoV-2 may have an association with rapidly increasing insulin daily needs. In case one, not only fear of COVID-19 delayed hospital attendance but also the setting of a low socioeconomic status family appears to have enhanced the risk for late diagnosis and challenging disease management.info:eu-repo/semantics/publishedVersio

Rendimiento escolar y tipos de errores en la lectura en los niños con alteraciones de la función visual

Se desarrolló un estudio descriptivo con el objetivo de evaluar el rendimiento escolar así como tipos de errores en la lectura en niños con alteraciones de la función visual. En el estudio participaron 672 niños del Municipio de Lisboa (7.69±1.19 años): grupo de control (función visual normal=562) y grupo experimental (alteraciones da función visual=110). Se cuestionaron 34 profesores acerca del rendimiento escolar y lectura a través de un cuestionario validado (α=0,91). Para la evaluación en la lectura se empleó la prueba de lectura de 34 palabras sueltas. Los niños con la función visual alterada mostraron niveles más bajos de rendimiento escolar. Estaban en el nivel "negativo" del 10,9% de los niños con la función visual alterada y sólo del 5,3% de los niños con la función visual normal. Estos niños comenten más errores en la lectura (p<0,001) con un mayor número de no palabras (3,09±5,20) en comparación con los niños con la función visual normal (1,44±3,09). Comenten también más omisiones y adiciones de letras y confusiones de grafema, teniendo dificultades en el análisis global de la palabra. Se propone un modelo de orientación para los profesores

Therapeutic Approach to Parapneumonic Effusions and Empyemas

Face à inexistência de uma metodologia única e consensual na abordagem terapêutica dos derrames pleurais parapneumónicos e empiemas, os autores propõem um protocolo de orientação, que resultou da reflexão baseada na sua experiência e na bibliografia mais recente

Clear-water scour at comparatively large cylindrical piers

New long-duration clear-water scour data were collected at single cylindrical piers with the objective of investigating the effect of sediment coarseness, Dp=D50 (Dp = pier diameter; D50 = median grain size) on the equilibrium scour depth and improving the scour depth time evolution modeling by making use of the exponential function suggested in the literature. Experiments were carried out for the flow intensity close to the threshold condition of initiation of sediment motion, imposing wide changes of sediment coarseness and flow shallowness, d=Dp (d = approach flow depth). The effect of sediment coarseness on the equilibrium scour depth was identified; existing predictors were modified to incorporate this effect for U=Uc ≈ 1.0; Dp=D50 > ≈60 and d=Dp ≥ 0.5; the complete characterization of a known scour depth time evolution model was achieved for U=Uc ≈ 1.0, 60 < Dp=D50 < 500 and 0.5 ≤ d=Dp ≤ 5.0

A Retrospective Study of Orthoptic Students’ and Teaching Experience with the Introduction of Technology Promoting a Blended Learning Environment

Purpose: Evaluation of the students’ experience and academic achievements following the introduction of online learning. Methods and materials: In 2011, online learning activities were introduced in the teaching of the Research in Orthoptics module for final year undergraduate orthoptic students. The online learning activities were created and delivered in Moodle; an open-source online learning platform. Students from the academic year groups of 2012–13, 2013–14 and 2016–17 completed an online questionnaire. The questionnaire was divided into 6 categories (relevance, reflection, interactivity, tutor support, peer support and interpretation) with 4 questions within each category. A 5-point Likert scale was used to score each question. The sum of answers within each category ranged from 4 (negative perception) to 20 (positive perception). Student performance was assessed using the marks retrospectively for 2 years before online learning was introduced and when online learning was included. Results: Forty-two students replied to the questionnaire with a mean age of 23.0 ± 2.3 years (range 21–32). There were 38 females (90.5%) and 4 males (9.5%). Combining the 3 academic cohorts there was a significant difference between the 6 categories of the questionnaire (p < 0.0001). Three categories obtained the same high median score of 16: relevance (range 9–20), reflection (range 11–20) and tutor support (range 12–20). Peer support resulted in the lowest median score of 13. Separation of the three academic year cohorts’ revealed significant differences for tutor support (p = 0.03). The score increased from 16 in 2012–13 and 2013–14 to 18 in 2016–17. Significant differences were found between the marks for the cohorts from 2009–10 to 2016–17 (F7,245 = 5.07: p < 0.0001). The mean mark for year group 2009–2010 was significantly less compared to 2012–13 (p < 0.0001), 2014–15 (p = 0.01) and 2015–16 (p = 0.02) and year group 2011–12’s mark significantly less than 2012/13 (p = 0.001). Conclusions: Including online learning in the research module had a positive impact on the student experience, although more work needs to be done to improve peer support. Marks obtained by the orthoptic students have improved since the introduction of online learning suggesting that a mixture of teaching and learning methods is beneficial for students. However, more work needs to be done to provide teacher assistance in the design of online learning and blended learning approach

Electrical properties of cork and derivates

The electrical properties of natural cork, commercial cork agglomerates (for floor and wall covering) and a composite of cork/TetraPak® were studied. The composite was developed at LNEG/Portugal and is made of recycled cork and TetraPak® containers. Measurements of isothermal charge and discharge currents (ICC/IDC) and dielectric relaxation spectroscopy (DRS) were made. The isothermal currents characteristics and the samples electrical conductivity were investigated under different conditions (electric field, temperature and measuring atmosphere). Dielectric relaxation spectroscopy was used to quantify the changes in the permittivity with the samples conditioning. Both experimental techniques showed the strong influence of water content on the electrical properties of cork and its derivatives

Can heart tissue fatty acid profile be used as a tool to discriminate sea lamprey (Petromyzon marinus, L.) populations in several Portuguese river basins?

This study proposes to evaluate the use of heart tissue fatty acid signature and multivariate analysis of fatty acid profile as a possible discriminating tool for sea lamprey P. marinus populations sampled in Portuguese river basins. Local fisherman collected adult sea lampreys in eight Portuguese river basins (Minho, Lima, Cávado, Douro, Vouga, Mondego, Tagus and Guadiana) at the beginning of their spawning migration. Heart total lipid extraction was obtained by accelerated solvent extraction (ASE) and FAMEs were prepared by transesterification with methanol-boron trifluoride and analysed by GC. FAMEs were identified by comparison of their retention times with known standards chromatographed in identical gas chromatography conditions. The fatty acid profile of the heart tissue varied among the individuals of the different river basins. In order to identify which fatty acid contributed most to the differences between river basins heart tissue, MDA was employed. The MDA proved to be statistically significant and the overall corrected classification rate estimated from cross-validation procedure was 86.2%. Although in the case of the individuals of Tagus and Guadiana 100% and 94.7 % of subjects were correctly classified, respectively, there are always a few individuals of the other 5 watersheds that have characteristics identical to those observed in these two river basins.The results are discussed in terms of fatty acid origin and hypothesis concerning the migratory behavior that could lead to these results. The fatty acid profile of heart is considered more stable than other organs, but it still exhibits some variability. This study seems to point out the potential for fatty acid compositions to discriminate sea lampreys from Portuguese river basins, which are probably related with environmental variables that they may have been exposed during early stages of their life cycle

Assessment of microbiota present on a Portuguese historical stone convent using high-throughput sequencing approaches

The study performed on the stone materials from the Convent of Christ revealed the presence of a complex microbial ecosystem, emphasizing the determinant role of microorganisms on the biodecay of this built cultural heritage. In this case study, the presence of Rubrobacter sp., Arthrobacter sp., Roseomonas sp., and Marinobacter sp. seems to be responsible for colored stains and biofilm formation while Ulocladium sp., Cladosporium sp., and Dirina sp. may be related to structural damages. The implementation of high-throughput sequencing approaches on the Convent of Christ's biodecay assessment allowed us to explore, compare, and characterize the microbial communities, overcoming the limitations of culture-dependent techniques, which only identify the cultivable population. The application of these different tools and insights gave us a panoramic view of the microbiota thriving on the Convent of Christ and signalize the main biodeteriogenic agents acting on the biodecay of stone materials. This finding highlighted the importance of performing metagenomic studies due to the improvements and the reduced amount of sample DNA needed, promoting a deeper and more detailed knowledge of the microbiota present on these dynamic repositories that support microbial life. This will further enable us to perform prospective studies in quarry and applied stone context, monitoring biogenic and nonbiogenic agents, and also to define long-term mitigation strategies to prevent biodegradation/biodeterioration processes