Search

This study analyzes the effect of text-inserted questions and post-text-reading questions, i.e., questions timing, on students’ processing and learning when studying challenging texts. Seventy-six freshmen read two science texts and answered ten adjunct questions with the text available, being tested on learning 5 days afterwards. Questions were presented either after reading the whole text or inserted in the text after reading the relevant information. Online processing data were recorded while reading and searching the texts, and measures of processing strategies (i.e., paraphrases, elaborations) while answering the questions were collected. Compared to students in the post-reading condition, those in the inserted condition spent more time reading the text initially, were more efficient at searching for information in the text, and produced more accurate elaborations, all of which may explain why answering inserted questions in an available text were more effective in terms of learning than answering post-reading questions. Limitations and educational implications of these results are also discussed.

Introduction. Students often answer questions from available expository texts for assessment and learning purposes. These activities require readers to activate not only meaning-making processes (e.g., paraphrases or elaborations), but also metacognitive operations (e.g., monitoring readers’ own comprehension or self-regulating reading behaviors) in order to successfully use textual information to meet the task demands. The aim of the study was to explore the meaning-making processes readers activate while answering questions and using textual information at hand, and how they monitor and control the processing of these tasks. Method. Forty eighth graders read two expository texts and answered ten multiple-choice comprehension questions per text. For each question, participants were forced to select the relevant pieces of textual information to provide the correct answer. Further, participants thought aloud in one of the texts, whereas they performed the task in silence in the other. This reading scenario served to collect valuable data on the reader’s question-answering process. The task was administered individually on a computer-based environment, which allowed recording the students’ reading behavior online. Results. Results showed processing differences between the two recursive steps of question-answering. While reading the question readers mainly restated information and focused on monitoring the comprehension of the questions and their correspondence with the alternatives. However, they tended to paraphrase and assess textual relevance when searching the text. The study also reveals that think-aloud methodology affected these processes and outcomes differently. Discussion and Conclusion. This study advances on our knowledge of cognitive and metacognitive processes involved in answering questions from an available text, a task extensively used to measure reading literacy skills as well as for learning purposes in academic settings. It shows how readers activate meaning-making processes while reading questions and searching the text for task-relevant information, and how they monitor the question-answering process. The study also reveals that think-aloud methodology may affect these processes differently. Apart from advancing our theoretical knowledge, our study also has important practical applications for the assessment of reading literacy skills.

Entre los múltiples residuos generados por la producción cafetera destaca la pulpa o cereza del fruto, la cual es responsable por cerca del 30% del peso en base seca del total del grano. La pulpa del café ofrece diferentes compuestos químicos de alto interés para la industria alimenticia y farmacéutica, donde destacan los compuestos fenólicos disponibles en esta, en especial los Ácidos Clorogénico, Cafeico, Ferúlico y Cumárico. Se realizó una extracción de los compuestos fenólicos por medio de una percolación en un equipo Soxhlet para evaluar el impacto del tipo de solvente, el tiempo de extracción y la relación de pulpa:solvente en el contenido de fenoles totales (TPC) del extracto. Se caracterizó el TPC de los 30 extractos realizados usando el método de Folin-Ciocalteu usando Ácido Gálico para la curva de calibración. Se encontró una influencia significativa en el TPC de cada extracto por el tipo de solvente utilizado en la extracción, mientras que los otros dos factores no fueron estadísticamente significativos. Se obtuvo un rendimiento máximo de de contenido de polifenoles por gramo de pulpa usado en la extracción utilizando Etanol al 95% de pureza. Se discute una oportunidad industrial en la extracción de los mencionados compuestos de la pulpa de café, donde los rendimientos alcanzados ofrecen un valor agregado al residuo, pudiendo beneficiar a la agroindustria cafetera con ingresos adicionales para los caficultores.

[EN] Plum pox virus(PPV) is the causal agent of sharka, the most devastating virus disease ofPrunusspecies. PPV is transmitted by vegetative propagation, particularly by grafting, as well as by aphid species in a nonpersistent manner. The objective of this paper was to evaluate the prevalence and diversity of PPV-vector aphid species in representative European areas of prunus cultivation. Four experimental nursery plots were established in Skierniewice (Poland), Liria (Spain), Plovdiv (Bulgaria) and Bistrita (Romania). Aphid population was weekly monitored using the sticky shoot method in spring and/or autumn in each nursery plot. Furthermore, we estimated the relative efficiency factor for the main PPV-vector aphid species using bibliographic and reference data. Aphid diversity in each nursery plot was assessed using the Shannon index and the number of estimated aphid species was calculated by the rarefaction method. The highest diversity of aphid species population was reported in Plovdiv in spring while the lowest diversity was found in Liria in spring. A cluster analysis based on Morisita-Horn similarity index was performed to study the differences in species composition between the four nursery plots and seasons. Aphid population was clearly grouped by location and season. Results showedAphis spiraecolaandHyalopterus prunicomplex were typically spring aphid species, whileAnoecia corniandRhopalosiphum padidominated autumn catch. Regarding PPV-vector aphid species present in nursery plots,A. spiraecolawas the most prevalent PPV-vector aphid species in Liria and in Bistrita, showing a high relative efficiency factor of PPV transmission (0.91). Consequently,A. spiraecolashould be considered a key actor in the spread of PPV in these regions.Hyalopterus prunicomplex was the most prevalent PPV-vector aphid species in Skierniewice and Plovdiv, showing a very low relative efficiency factor of PPV transmission (0.09). Therefore, the role ofH. prunicomplex in spread of PPV in these regions can be considered negligible. Furthermore, we statistically demonstrated that the presence of specific PPV-vector aphid species is associated with the spread of the disease, whereas the biodiversity of aphid species population does not affect the spread of PPV. Finally, the advantages of the use of vector pressure index in the management of sharka disease are discussed., The research leading to these results were funded by the EU Seventh Framework Programme (FP7/2007-2013), SharCo project grant no. 204429 and by grants from the Spanish Ministry of Science and Education (MEC, AGL2009-07531 and INIA RTA2005-00190). Authors thank I. Baias, S. Sabin (SCDP, Bistrita), B. Tamargo and J. Micó (Cooperativa Vinícola, Líria) for technical assistance in the experimental plots, Viveros Orero and Agromillora Iberia for providing the certified rootstock plants. E. Vidal was recipient of a grant from the Spanish Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA).

EnglishTeachers usually assign text comprehension activities to their students and provide them with feedback on the correctness of their answers for learning purposes. In traditional classrooms, teachers have little to no chance to delivering individual feedback in an adapted and timely manner. Digital environments overcome these limitations. Computer-based systems provide researchers and practitioners the opportunity to trace the student’s actions while performing tasks and transform data into individualized feedback messages immediately. Elaborated Feedback (EF) has proven to be more effective than mere corrective feedback, such as Knowledge-of-Response feedback (KR, e.g., Correct/Incorrect) or Knowledge-of-Correct-Response feedback (KCR, e.g., The correct response is X). EF may include additional information, such as monitoring hints, feedback about the student’s accuracy to assess textual relevance, or inference prompts. When performing question-answering tasks, students are expected to deploy both comprehension and specific reading skills (e.g., searching the text for task-relevant information). This work examines recent research recording online measurements on how students perform question-answering tasks and react to different forms of EF on their question-answering process. Overall, it suggests that computer-based EF may enhance both comprehension performance outcomes and text processing strategies, although students often pay more attention to the corrective part of feedback messages than to the additional information of EF, and they rarely engage in processing feedback deeply. Theoretical and practical contributions are discussed. francaisLes enseignants proposent habituellement des activites de comprehension de texte a leurs eleves et leur fournissent, a des fins d’apprentissage, une retroaction visant l’exactitude de leurs reponses. Dans les classes traditionnelles, les enseignants n’ont que peu d’opportunite pour fournir une retroaction individuelle adaptee. Les environnements numeriques surmontent ces limites. Les systemes informatises donnent aux chercheurs et aux praticiens l’occasion de retracer les actions de l’eleve qui execute les tâches et de transformer immediatement les donnees en messages de retroaction personnalises. La retroaction elaboree (RE) s’est averee plus efficace que la simple retroaction corrective, telle la retroaction sur la connaissance de la reponse (CR, par ex. Correct/Incorrect) ou la retroaction sur la connaissance de la reponse correcte (CRC, par ex. La bonne reponse est X). RE peut inclure des informations supplementaires, telles que des indices de suivi, des commentaires sur la precision de l’eleve pour evaluer la pertinence du texte, ou des invites d’inference. Lorsqu’ils repondent a des questions, les eleves doivent faire preuve a la fois de comprehension et d’aptitudes particulieres a la lecture (par ex. rechercher dans le texte de l’information pertinente). Cet article examine des recherches recentes qui enregistrent des mesures en ligne sur la facon dont les etudiants effectuent des tâches de questions-reponses et reagissent a differentes formes de RE sur leur processus de questions-reponses. Les resultats obtenus suggerent que la RE assistee par ordinateur peut ameliorer a la fois les resultats de comprehension et les strategies de traitement de texte, bien que les eleves accordent souvent plus d’attention a la partie corrective des messages de feedback qu’aux informations complementaires de la RE ; ils s’engagent par ailleurs rarement dans un traitement approfondi du feedback. Les contributions theoriques et pratiques presentees sont discutees.

Introdução: a atresia de vias biliares (AVB) é uma patologia pediátrica rara, mas é a principal causa de transplante hepático em crianças, se não revertida com a realização da portoenterostomia em Y-de-Roux (cirurgia de Kasai) em tempo adequado. Nota-se tendência de atraso do procedimento cirúrgico em todo o Brasil, sendo necessária investigação de sua causa. Objetivo: determinar o perfil epidemiológico do paciente com AVB e avaliar a atenção em saúde voltada para este em hospital terciário. Método: foi realizado um estudo descritivo, retrospectivo, transversal, a partir de prontuários dos pacientes com diagnóstico de AVB acompanhados em hospital terciário entre 1996 e 2015. Resultados: dos 72 pacientes da amostra inicial, somente 52 pacientes tiveram prontuários completamente disponibilizados pelo arquivo do hospital. Dentre os 26 pacientes incluídos, a média de idade à admissão foi de 87,9 dias (± 57,9), com realização de ultrassonografia (USG) em 24 casos e necessidade de repetição do exame em 10. A cirurgia de Kasai foi realizada em 50% dos pacientes, sendo 38,4% antes dos 60 dias de vida. Dos pacientes operados tardiamente, 25% foram transplantados e 50% foram a óbito, enquanto que, entre os 4 operados em tempo hábil, somente um foi transplantado e não houve óbitos. Conclusão: as dificuldades diagnósticas, em especial, falha de suspeição de AVB, na atenção básica ou terciária, além de um percentual de 41,6% de USG com resultados falso-negativos retardaram o momento cirúrgico, confirmando o pior desfecho do paciente operado tardiamente.

Introdução: Ao final de 2019, vários casos de infecção respiratórias de origem desconhecida surgiram na cidade de Wuhan, China, causando preocupação na comunidade científica e na população, devido a sua rápida transmissão e alto grau de mortalidade nos grupos de risco. Meses depois, a Organização Mundial de Saúde declarou o surto como emergência de saúde pública, denominando de novo coronavírus (SARS-Cov-2), conhecida mundialmente como COVID-19. Devido ao cenário imposto pelo coronavírus, ocorreu uma grande procura por estratégias farmacoterapêuticas, porém, até o momento, ainda não há protocolos estabelecidos para esta patologia. Dentre os fármacos com crescentes taxas de automedicação destaca-se a ivermectina, um agente antiparasitário que embora estudos demonstrem sua atividade in vitro, impedindo a replicação viral do SARS-Cov-2, a dose necessária para alcançar atividade antiviral em humanos é mais de cem vezes a dose usual, podendo causar efeitos tóxicos se usado de forma irracional. Objetivos: Avaliar os riscos potenciais associados ao uso indiscriminado de ivermectina na pandemia da COVID-19. Materiais e métodos: Realizou-se uma revisão de literatura de caráter descritivo nas bases de dados: SciELO, PubMed e BVS. Utilizou-se os descritores: Ivermectina “ivermectin”, COVID-19 e Uso indiscriminado “indiscriminate use” sendo combinados pelo operador booleano “AND”. Selecionou-se artigos entre os anos de 2020 e 2021, dentro dos idiomas inglês e português, de caráter descritivo, exploratório ou experimental, com conteúdo relativo ao objetivo do estudo. Estudos que não se enquadravam nesses critérios foram excluídos. Encontrou-se 426 (quatrocentos e vinte e seis) artigos sobre a temática, mas, após aplicação dos critérios de exclusão restaram-se apenas 16 artigos. Resultados: Foi possível observar que a utilização de ivermectina, de forma indiscriminada, pode causar diversos problemas, dentre os quais destacam-se: resistência bacteriana e parasitária, distúrbios gastrointestinais, fraqueza muscular, hipotensão, taquicardia e hepatite medicamentosa em pacientes com COVID-19. Conclusão: Apesar deste fármaco ocasionar diversos efeitos adversos, ainda é necessário que novos estudos acerca da avaliação da ivermectina como agente antiviral e seu efeito na COVID-19 sejam realizados pois, o mesmo, em estudos in vitro, foi capaz de impedir a replicação viral do novo coronavírus. Entretanto, ainda não existem evidências fortes acerca de seu efeito para esta patologia.

OBJETIVO: Avaliar os aspectos epidemiológicos e a assistência pré e pós-natal de pacientes tratados com hérnia diafragmática congênita (HDC) em um hospital terciário no nordeste do Brasil. MÉTODOS: Foi realizado um estudo descritivo, retrospectivo do tipo corte transversal através da análise dos prontuários dos pacientes com diagnóstico de HDC no período entre janeiro de 2008 a dezembro de 2017. Foram estudados aspectos relacionados ao pré-natal, ao puerpério imediato e ao período pós-natal, observando as taxas de sobrevida, características da hérnia e do tratamento da patologia. O estudo se desenvolveu através do preenchimento de formulários de acordo com os dados colhidos nos prontuários desses pacientes e de suas genitoras. RESULTADOS: Entre os 54 pacientes analisados, 64,8% foram diagnosticados no período pré-natal. 38% apresentavam a falha no lado esquerdo do diafragma e 50% dos pacientes tinham registro de fígado intratorácico. 63% dos pacientes foram submetidos à correção cirúrgica. 53,7% dos portadores de hérnia diafragmática congênita evoluíram para óbito. CONCLUSÃO: Observou-se uma elevada taxa de mortalidade entre os pacientes, principalmente daqueles que são portadores de outras malformações além da hérnia diafragmática congênita, sendo necessário investigar e avaliar a presença das mesmas durante o pré-natal e no período pós-natal.

The goal of this study was to examine how students process formative feedback that included corrective and elaborative information in online question-answering tasks. Skilled and less-skilled comprehenders in grade 8 read texts and answered comprehension questions. Prior to responding, students were asked to select the textual information relevant to answer each question. Students received formative feedback that included information about the answer correctness and an elaborative message, either automatically delivered or optionally accessed. Students’ actions, as well as verbal protocols during feedback processing, were recorded. The results showed that: (a) students paid more attention to the answer correctness than to elaborative feedback messages; (b) students paid more attention to feedback information after failure than after success; (c) students actively monitored the accuracy of their responses; and (d) differences between skilled and less-skilled comprehenders in processing feedback were very limited. Theoretical and practical implications of these results are discussed.

Within the context of finite-time thermodynamics several regimes of performance have been used to study the well known Curzon-Ahlborn (CA) heat engine model [1-5]. Also the optimal performance and the effects on environment are studied to find the best approximation with real heat engines. In this work we present a model of an arrangement in series of irreversible Carnot heat engines, which consist of k reservoirs connected in series, this heat engine model is working under three different regime of performance: maximum power output, maximum ecological function [6] and maximum efficient power [7]. At first we used three reservoirs, and we calculated its efficiency. For the case of maximum power output we calculated the efficiency for the case of the generalizing of k reservoirs, and we get an efficiency expression similar to the one of Curzon-Ahlborn, the irreversibilities are taken into account by irreversibility parameter R. Finally we present the comparison of the efficiencies obtained under three differents regimes of performance.

O compósito cerâmico Al2 O3 -YAG possui alta resistência à corrosão e à fluência em ambientes agressivos, o que permite vislumbrar aplicações bastante atrativas, tais como aletas de motores a jato e de turbinas a gás. Esse compósito também apresenta elevada dureza e alta resistência à abrasão, possibilitando o seu emprego em blindagens balísticas. Uma de suas rotas de produção é por meio da sinterização de pós de Al2 O3 e Y2 O3 ou YAG. Neste estudo, os pós-precursores de Al2 O3 e YAG foram sinterizados em presença de fase líquida, com uso de Nb2 O5 como aditivo de sinteriza- ção. O objetivo desta pesquisa foi analisar o comportamento das propriedades físicas e morfológicas, desse produto final. Os pós foram cominuídos em moinho de bolas planetário por 4h, secados em estufa a 120°C por 48h, desaglomerados e peneirados. A mistura obtida foi, em seguida, compactada a 70 MPa, por 20s e os corpos verdes produzidos foram sinterizados a 1450°C por 180min. Os materiais sinterizados foram caracterizados por difração de Raios X (DRX) com a determina- ção semiquantitativa de fases pelo Método de Rietveld, Microscopia Eletrônica de Varredura (MEV) com avalia- ção por Espectrometria de Dispersão de Energia (EDS), densidade e porosidade. A densidade medida, de 64%, revelou que a densificação completa não foi atingida e que ainda são necessários ajustes nas condições de sinterização.

One of the main objectives of violin acoustics is a detailed analysis of the vibration state of the instrument, the source of its sound. The goal of this work was to extend a straightforward technique, naked-eye and non-destructive, to detect details of violin vibrations: laser streak patterns. Essentially, the experimental set-up only requires harmonically driving a violin in resonance, illuminating its surface with a handheld laser, and focusing on the speckle plane. The streak patterns obtained from signature modes of the violin revealed details hardly available using other real-time techniques. For example, results showed the behavior of the island —the area between the f-holes— changing from rigid rocking in CBR to bending motion in B 1 - and B 1 + ; in fact, the high sensitivity of the streak patterns even allowed detecting specific areas with major deflections on the island: the soundpost side in B 1 - , and the bassbar side in B 1 + . Therefore, employing streak patterns as a tool for real-time analysis of violins is encouraged not only for researchers but also for violin makers.

Internet-based reading involves integration and evaluation of information from different sources and different formats, but also requires fluent navigation skills for adequate comprehension. The effects of linguistic (word decoding and comprehension-based print reading) and non-cognitive factors (reading frequency and self-efficacy) have extensively been studied for print reading; we know very little about their role in Internet reading, which is our focus in this study. 558 students from grades 7 to 10 performed a set of comprehension-based Internet reading tasks on a computer, while their navigation and comprehension scores were recorded. They were also assessed on print reading literacy, word decoding, Internet reading frequency and self-efficacy. Multiple regression analyses suggest that navigation skills increase proportionally with grade level and that print reading literacy and comprehension-based Internet reading share common processes. Moreover, the positive effect of navigation efficiency on Internet comprehension increases in higher grade levels. Finally, reading frequency of the Internet for informational purposes predicts Internet comprehension scores, and self-efficacy predicts more persistent and quicker navigation.

We conducted two experiments to analyze how text availability and question format affect readers’ processes and performance on measures of expository text reading comprehension. Junior high school students read expository texts and answered both multiple choice and open-ended questions on a computer that recorded reading times and readers’ actions with Read&Answer software. The results showed that readers reread prior text segments during initial reading of the text more often when they knew that the text would be unavailable when answering questions than when they knew that the text would be available. In addition, readers made more search decisions in the text- available condition when answering open-ended questions than when answering multiple-choice questions. Regarding performance, we repeatedly found an interaction effect between availability and question format: text availability benefited the open-ended but not the multiple-choice format. We concluded that the two availability conditions are useful in assessing different discourse processes. We discuss theoretical and practical implications for the development of models of reading and new ways to assess reading literacy skills that emphasize purposeful reading.

Direct systems to process samples allow high-throughput testing or identification of Citrus tristeza virus (CTV) by the sensitive real-time reverse transcription coupled to polymerase chain reaction (RT-PCR) neither with extract preparation nor nucleic acid purification. Immobilized CTV targets are amplified from fresh sections of plant tissues or squashes of fresh or already caught vectors onto paper, nitrocellulose, or positively charged nylon membranes. The printed or squashed support can be stored or mailed at room temperature. These validated user-friendly methods are recommended by IPPC-FAO standard for CTV diagnosis, detection, and identification. The methods are safe, not under current quarantine regulations because they do not involve any risk of introduction of exotic CTV isolates or vectors and are discrete and useful for epidemiological studies or screening for large-scale analyses. In this chapter, tissue-printing and squashing capture methods for direct sample preparation without extract preparation or nucleic acid extraction and purification were coupled with validated real-time RT-PCR detection protocols based on TaqMan chemistry for CTV detection.