Mobile learning: benefits of augmented reality in geometry teaching

As a consequence of the technological advances and the widespread use of mobile devices to access information and communication in the last decades, mobile learning has become a spontaneous learning model, providing a more flexible and collaborative technology-based learning. Thus, mobile technologies can create new opportunities for enhancing the pupils’ learning experiences. This paper presents the development of a game to assist teaching and learning, aiming to help students acquire knowledge in the field of geometry. The game was intended to develop the following competences in primary school learners (8-10 years): a better visualization of geometric objects on a plane and in space; understanding of the properties of geometric solids; and familiarization with the vocabulary of geometry. Findings show that by using the game, students have improved around 35% the hits of correct responses to the classification and differentiation between edge, vertex and face in 3D solids.This research was supported by the Arts and Humanities Research Council Design Star CDT (AH/L503770/1), the Portuguese Foundation for Science and Technology (FCT) projects LARSyS (UID/EEA/50009/2013) and CIAC-Research Centre for Arts and Communication.info:eu-repo/semantics/publishedVersio

Assessing patterns of geographic dispersal of Gelidium sesquipedale (Rhodophyta) through RAPD differentiation of populations

Randomly amplified polymorphic DNAs (RAPDs) of bulked genomic DNA samples were used to analyse the genetic differentiation of Gelidium sesquipedale populations. They reflect the pat terns of gene flow, which in turn depend on the dispersal mechanisms of the species and on near-shore ocean currents. Fourteen populations were sampled from northern France to Morocco, covering the geographical distribution of the species. A single bulk DNA sample (from 15 individuals) was used in each population, under the assumption that the resulting patterns represent the populations' most common genetic features. To test this, we investigated the genetic variability among 5 bulk samples within a single population. Genetic distances among bulks were very low (average = 0.065) and were signifi- cantly lower than those observed between geographically separated populations (average = 0.241). Neighbour-joining analysis of the distance matrix of populations separated a well-supported group including populations of northern Spain and of northern France, and a less-supported group containing populations of northern Portugal. Multidimensional scaling of the genetic distance matrix revealed 2 isolated populations, Sao Rafael in southern Portugal and Algeciras in southern Spain. These patterns of genetic differentiation are discussed under the available data on the near-shore ocean currents. Results suggest that the genetic differentiation of G. sesquipedale populations may be used as a biological tracer of prevailing flows and barriers of the near-shore currents. A positive correlation between geographical and genetic distances of G. sesquipedale populations along the species geographical dis tribution was found, suggesting that a continuous transport of detached fronds and their reattachment to new substrate must be an effective dispersal mechanism of the species, sustaining the gene flow among populations

Hypophosphatemia As a Possible Biomarker for Epileptic Seizures at the Emergency Department

Introduction: Hypophosphatemia seems to be temporally associated with seizures, despite not being considered a trigger. We aimed to evaluate hypophosphatemia as a biomarker for seizures. Methods: Retrospective study, including all consecutive patients admitted at our central hospital's emergency department from 01/01-31/03/2021, screened as "altered consciousness/syncope" or "seizures", with available phosphate levels. Results: 277 patients included, mostly male (61.7%), mean age 64.3 years. Final diagnosis was "seizure" in 34.7% and "other diagnosis" in 65.3%. Patients with seizures were younger (p200U/L) was more frequent in the seizure group (p=0.04). Odds ratio (OR) of hypophosphatemia for seizures was 4.330 (CI 95% 2.170-8.640, p<0.001), persisting after correction for confounders. OR of hyperCK was 1.890 (CI 95% 1.060-3.371, p=0.03), losing significance when adjusted. Sensitivity was low for both. Hypophosphatemia was more specific (91.2% vs 79.9%). Conclusions: Our findings support hypophosphatemia as a seizure biomarker. More studies are needed.info:eu-repo/semantics/publishedVersio

Artificial reefs: from ecological processes to fishing enhancement tools

info:eu-repo/semantics/publishedVersio

Recycling of cellulases in lignocellulosic hydrolysates using alkaline elution

The recovery of cellulases from lignin, lignocellulosic hydrolysates and cellulose by alkaline washes at pH 9 and 10 was examined. The effect of the pH on the structural stability of purified Cel7A was analyzed by circular dichroism. Purified Cel7A showed conformational changes at pH 9 and 10 that were reversible at pH 4.8. Temperature influenced the enzymatic hydrolysis of wheat straw and may be critical for the efficiency of cellulase recycling from wheat straw hydrolysates. Operation at moderate temperatures (37 °C) resulted in a rate of saccharification 19% higher than that obtained at 50° C, improving cellulase recycling by 49%. Over 60% of the enzyme activity on the synthetic substrate 4-methylumbelliferyl-β-d-cellobioside (MUC) may be recovered by using a simple alkaline wash. This is thus a promising strategy for enzyme recycling that is simple to implement at industrial scale, economical and effective.The authors acknowledge funding through FP7 KACELLE (Kalundborg Cellulosic Ethanol) project for supporting his work. We also thank Dr. Mai Ostergaard Haven for critical reviewing of the manuscript and Dr. Jane Lindedam for supplying the lignin

Assessing estuarine environmental quality using fish-based indices: Performance evaluation under climatic instability

http://www.sciencedirect.com/science/article/B6V6N-4TFDY7X-2/2/c9f9bbc565621cbb798d6d663e74a8f

Carbon dots from tryptophan doped glucose for peroxynitrite sensing

Tryptophan doped carbon dots (Trp-CD) were microwave synthesized. The optimum conditions of synthesizing of the Trp-CD were established by response surface multivariate optimization methodologies and were the following: 2.5 g of glucose and 300 mg of tryptophan diluted in 15 mL of water exposed for 5 min to a microwave radiation of 700 W. Trp-CD have an average size of 20 nm, were fluorescent with a quantum yield of 12.4% and the presence of peroxynitrite anion (ONOO−) provokes quenching of the fluorescence. The evaluated analytical methodology for ONOO− detection shows a linear response range from 5 to 25 μM with a limit of detection of 1.5 μM and quantification of 4.9 μM. The capability of the ONOO− quantification was evaluated in standard solutions and in fortified serum samples

Efeito das condições de cura no comportamento da resistência à compressão em resíduos de cerâmica ativados por álcali

The industrial sector is responsible for the generation of a large amount of solid waste, of which some is partially recycled, but the majority is deposited in landfills or landfills causing various negative impacts on the environment. Alkaline cements are attracting growing interest for their potential to allow the industry to operate within the constraints imposed on CO2 emissions. The objective of this research was to know the effect of different curing conditions on the compressive strength behavior of alkaline activated ceramic residues. As a result, it was determined that an alkali-activated matrix is significantly influenced when cured at a temperature of 70 ° C, reaching, at 90 days of age, a compressive strength of up to 39.3 MPa in contrast to 27.08 MPa. when curing was carried out in environmental conditions of 20 ° C (± 0.5 ° C) and 60% (± 5%) of relative humidity (RH). This work was complemented with a microstructural analysis that included Scanning Electron Microscopy (SEM) and X-ray Energy Dispersion Analyzer (EDX).El sector industrial es responsable de la generación de una gran cantidad de residuos sólidos, de los cuales algunos son parcialmente reciclados, pero la mayoría son depositados en vertederos o rellenos sanitarios provocando diversos impactos negativos en el medio ambiente. Los cementos alcalinos están atrayendo un interés creciente por su potencial para permitir que la industria opere dentro de las limitaciones impuestas a las emisiones de CO2. La presente investigación tuvo como objetivo conocer el efecto de diferentes condiciones de curado sobre el comportamiento de resistencia a compresión de los residuos cerámicos activados alcalinamente. Como resultado se determinó que una matriz álcali-activada es significativamente influenciada cuando se cura con una temperatura de 70°C alcanzando, a los 90 días de edad, una resistencia a la compresión de hasta 39,3 MPa en contraste con 27,08 MPa cuando el curado se realizó en condiciones ambientales de 20°C (± 0,5 ° C) y 60% (± 5%) de humedad relativa (RH). Este trabajo se complementó con un análisis microestructural que incluyó Microscopía electrónica de barrido (SEM) y Analizador de dispersión de energía de rayos X (EDX).O setor industrial é responsável pela geração de grande quantidade de resíduos sólidos, alguns deles parcialmente reciclados, mas a maior parte é depositada em aterros ou aterros sanitários causando diversos impactos negativos ao meio ambiente. Os cimentos alcalinos estão atraindo cada vez mais interesse por seu potencial de permitir que a indústria opere dentro das restrições impostas às emissões de CO2. O objetivo desta pesquisa foi conhecer o efeito de diferentes condições de cura no comportamento da resistência à compressão de resíduos cerâmicos alcalinos ativados. Como resultado, determinou-se que uma matriz alcalina ativada é significativamente influenciada quando curada a uma temperatura de 70 ° C, atingindo, aos 90 dias de idade, uma resistência à compressão de até 39,3 MPa em contraste com 27,08 MPa. quando a cura foi realizada em condições ambientais de 20 ° C (± 0,5 ° C) e 60% (± 5%) de umidade relativa (UR). Este trabalho foi complementado com uma análise microestrutural que incluiu Microscopia Eletrônica de Varredura (MEV) e Analisador de Dispersão de Energia de Raios-X (EDX)

Interceptação da radiação fotossinteticamente ativa e índice de área foliar da cana-de-açúcar irrigada em Juazeiro, Bahia.

Este estudo teve o objetivo de analisar a sazonalidade da radiação fotossinteticamente ativa e sua fração interceptada pela cana-de-açúcar irrigada sob as condições climáticas do Submédio do Vale São Francisco