Combining Indexing Schemes to Accelerate Querying XML on Content and Structure

This paper presents the advantages of combining multiple document representation schemes for query processing of XML queries on content and structure. We show how extending the Text Region approach [2] with the main features of the Binary Relation approach developed in [8] leads to a considerable speed-up in the processing of the XPath location steps. We detail how, by using the combined scheme, we reduce the number of structural joins used to process the XPath steps, while simultaneously limiting the amount of memory usage. We discuss optimisation strategies enabled by the new `combined representation scheme'. Experiments comparing the efficiency of alternative query processing strategies on a subset of the queries used at INEX 2003 (the Initiative for the Evaluation of XML Retrieval [4]) demonstrate a favourable performance for the combined indexing scheme

XML and Context: Structural Features Relevant to Search Tasks

We describe ongoing research into the relationship between search tasks and information retrieval strategies with respect to the use of structural information. We define a classification of search tasks in structured document collections and analyse the relevance of different structural features regarding each of these tasks for the INEX collection. The results presented show important differences in relevance of different features such as size and type of the components regarding informational and resource tasks

La familia y el juego como estrategia de aprendizaje a distancia durante la pandemia del Covid-19 en México: Una propuesta desde la enseñanza universitaria en ciencias de la salud

The pandemic by Covid-19 has impacted the ways of learning, so that the sudden change from the face to face modality to distance education as a measure to precent contagion, it is a phenomenon that must be investigated to provide alternatives that support the learning process from home. The aims this present study are design, apply, evaluate and propose learnig strategies for students to reach their máximum potential through distance education during the pandemic. For it an educational action research was carried out with one hundred and twenty health science students (nursing and physioterapy) from the Universidad de Guadalajara, during March to October 2020. Distance learning strategies were carried because out to the suspension of face to face clases due to Covid-19, wich they were based on family participation and the insertion on the play in the learning activities of the medical etymologies course. The evaluation of the strategies was carried out by collecting the evidence of learning and a virtual self-evaluation questionnaire. It was found that including family and play in distance education helped mitigate the negative effects of confinement from the pandemic, wich has also strengthened the resilience of students.La pandemia por Covid-19 ha impactado las formas de aprender, por lo que el cambio repentino de la modalidad presencial a la educación a distancia como medida para prevenir contagios, es un fenómeno que debe ser investigado para brindar alternativas que apoyen el proceso de aprendizaje desde casa. La presente investigación tiene por objetivo diseñar, aplicar, evaluar y proponer estrategias de aprendizaje para que los estudiantes alcancen su máximo potencial por medio de la educación a distancia durante la pandemia. Para ello se llevó a cabo una investigación-acción educativa con ciento veinte estudiantes de ciencias de salud (enfermería y terapia física), de la Universidad de Guadalajara, durante los meses de marzo a octubre de 2020. Las estrategias de aprendizaje se aplicaron en la modalidad a distancia debido a la suspensión de clases presenciales por el Covid-19 y se basaron en la participación de la familia y la introducción del juego en las actividades de aprendizaje del curso de etimologías médicas. La evaluación de las estrategias se llevó a cabo mediante la recogida de las evidencias de los aprendizajes y un cuestionario virtual de autoevaluación de las mismas. Se encontró que incluir a la familia y el juego en la educación a distancia ayudó a mitigar los efectos negativos del confinamiento por la pandemia, lo cual, además ha fortalecido la resiliencia de los estudiantes

Taxonomic composition and substrate affinity of conspicuous marine macroalgae of the Parque Nacional Arrecifes de Cozumel, Quintana Roo, Mexico

Antecedentes y Objetivos: Los arrecifes del Parque Nacional Arrecifes de Cozumel constituyen una de las principales formaciones arrecifales de México. Sin embargo, actualmente, son prácticamente inexistentes los estudios ficoflorísticos que permiten detectar cambios en la composición ficoflorística o su afinidad por algún sustrato. Por lo tanto, nuestro objetivo fue determinar la composición taxonómica de macroalgas marinas presentes en el Parque Nacional Arrecifes de Cozumel, así como realizar sus descripciones morfológicas y análisis de afinidad con el sustrato que colonizan. Métodos: Los muestreos se realizaron en octubre y noviembre de 2018 en 14 arrecifes del Parque Nacional Arrecifes de Cozumel, mediante buceo autónomo. Se realizaron observaciones morfo-anatómicas utilizando tanto microscopios ópticos como estereoscópicos. La determinación taxonómica se realizó a partir de literatura especializada. Resultados clave: Se determinaron 42 taxa: cinco Ochrophyta, 12 Rhodophyta y 25 Chlorophyta. La familia mejor representada para Ochrophyta fue Dictyotaceae; para Rhodophyta, Ceramiaceae y Rhodomelaceae; y para Chlorophyta, Halimedaceae. Se describen nuevos registros para el Parque Nacional Arrecifes de Cozumel incluyendo a Lobophora guadeloupensis como nuevo registro para México. Adicionalmente, se identificaron cuatro diferentes sustratos para las algas: psamofítico (33%), epilítico (32%), epizoico (19%) y epífito (16%). Los arrecifes más diversos fueron La Francesa (LF) y Santa Rosa (SR), y los menos diversos fueron Chankanaab (CK) y Tormentos (TM). Conclusiones: Aunque muchos de los registros previos en el área fueron confirmados en el presente estudio, la presencia de 18 nuevos registros reveló, por un lado, la falta de monitoreos constantes de la riqueza algal de la región, y, por otro lado, la necesidad de contar con descripciones morfológicas o referencias fotográficas que permitan contrastar los registros previos con los actuales. Dada la importancia del Parque Nacional Arrecifes de Cozumel, nuestros resultados, además de ofrecer información actualizada, representan un punto de partida para estudios en biología de la conservación.Background and Aims: The reefs of the Parque Nacional Arrecifes de Cozumel constitute one of the main reef formations in Mexico. However, up to date phycofloristic studies that allow detecting changes in the phycofloristic composition or its affinity for some substrates are practically non-existent. Our aim was to determine the taxonomic composition of marine macroalgae present in the Parque Nacional Arrecifes de Cozumel, as well as realize their morphological descriptions and an analysis of their affinity with the substrate they colonize. Methods: The sampling was carried out in October and November 2018 by autonomous diving in 14 reefs of the Parque Nacional Arrecifes de Cozumel. Morphological observations were made using optical and stereoscopic microscopes. The taxonomic determination was made using specialized literature. Key results: Fourty-two taxa were determined: five Ochrophyta, 12 Rhodophyta and 25 Chlorophyta. The best-represented family for Ochrophyta was Dictyotaceae; for Rhodophyta, Ceramiaceae and Rhodomelaceae; and for Chlorophyta, Halimedaceae. New records for the Parque Nacional Arrecifes de Cozumel are described, including Lobophora guadeloupensis as a new record for Mexico. Additionally, four different substrates for the algae were identified: psammophytic (33%), epilithic (32%), epizoic (19%) and epiphytic (16%). The most diverse reefs were La Francesa (LF) and Santa Rosa (SR), whereas the least diverse were Chankanaab (CK) and Tormentos (TM). Conclusions: Although many of the previous records in the area were confirmed in the present study, the presence of 18 new records revealed, on the one hand, the lack of constant monitoring of the algal richness of the region, and on the other hand, the need for morphological descriptions or photographic references that allow contrasting the previous records with the current ones. Given the importance of the Parque Nacional Arrecifes de Cozumel, our results, in addition to offering updated information, represent a starting point for studies in conservation biology

Structural features in content oriented XML retrieval

The structural features of XML components are an extra source of information that should be used in a content-oriented retrieval task on this type of documents. In this paper we explore one of the structural features from the INEX collection that could be used in content-oriented search. We analyse the gain this knowledge could add to the performance of an information retrieval system and present a first approach on how this structural information could be extracted from a relevance feedback process to be used as priors in a language modelling framework

Comparative digital study of two cranial rotation methods of the proximal fragment on the center of rotation of angulation-based leveling osteotomy planning with different tibial distal anatomical axes

The center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) technique was developed for cranial cruciate ligament (CrCL) rupture treatment, aiming to modify the mechanical-anatomical angle (AMA), which is described as a predictive risk factor for the disease and is recommended to be taken into consideration when one is choosing a surgical procedure for tibial plateau slope alteration. Identifying a tibial distal anatomical axis (DAA) is essential in CBLO surgical planning and measuring AMA amplitude. The aim of this study was: to evaluate two methods of cranial rotation of the proximal fragment using four different tibial distal anatomical axes for digital planning on the CBLO technique, comparing its effectiveness in achieving the desired tibial plateau angle (TPAd) and closing the AMA angle. Tibial measurements were made with the vPOP pro software using 30 mediolateral radiographs of canine stifles. The DAA described by four authors was used based on the amount of Rotation completed (Rc) for each. The rotation methods evaluated were: 1) commercial CBLO table (RT) and 2) overlapping the tip of the intercondylar eminence with the corresponding DAA line (RE). The TPAd to be obtained was fixed at 10°, and the final AMA to be achieved at 0°. The mean values and standard deviations of the final TPA and final AMA with the rotation method were TPA(RT)f(%TPAd), TPA(RE)f(%TPAd), AMA(RT)f(%AMAzero), AMA(RE)f(%AMAzero). The results of each author were Hulse 10.0 ± 0.3(46.6%), 9.9 ± 0.1(60%), 0.3 ± 0.3(33.3%), 0.3 ± 0.3(13.3%), Osmond 10.1 ± 0.2(75%), 10,1 ± 0.2(83.3%), 0.4 ± 0.4(33.3%), 0.4 ± 0.3(8,3%), Miles 10.0 ± 0.1(66.6%), 10.0 ± 0.1(75%), 0.2 ± 0.1(16.6%), 0.2 ± 0.1(8.3%), Tudury 9.6 ± 0.6(31.2%), 9.5 ± 0.2(31.2%), 1.0 ± 0.7(18.7%), 1.0 ± 0.6(12.5%), respectively. The initially described RT obtained a higher percentage of AMA at zero degrees. Therefore, the RE method is discarded for use as an alternative to CBLO planning.A técnica da osteotomia de nivelamento baseada no centro de rotação de angulação (CORA) chamada CBLO foi desenvolvida para o tratamento da ruptura do ligamento cruzado cranial (RLCCr), visando modificar o ângulo mecânico-anatômico (AMA), o qual é descrito como fator de risco preditivo para a doença e é recomendado que seja levado em consideração na escolha do procedimento cirúrgico para alteração da inclinação do platô tibial. A identificação de um eixo anatômico distal da tíbia (EAD) é um passo fundamental no planejamento cirúrgico da CBLO e para avaliar a amplitude do AMA. O objetivo deste estudo foi: avaliar dois métodos de rotação craniana do fragmento proximal utilizando quatro eixos anatômicos distais tibiais diferentes para o planejamento digital da técnica CBLO, comparando sua eficácia para atingir o ângulo do platô tibial desejado (TPAd) e no fechamento do AMA. As medidas tibiais foram feitas no software vPOP pro usando 30 radiografias medio-laterais de joelhos caninos. Foi utilizado o EAD descrito por quatro autores diferentes, baseada na quantidade de Rotação concluída (Rc) para cada um deles. Os métodos de rotação avaliados foram: 1) tabela comercial de CBLO (RT) e 2) sobreposição da ponta da eminência intercondilar com a linha EAD correspondente (RE). O TPAd a ser obtido foi fixado em 10° e o AMA final a ser alcançado em 0º. A média e o desvio padrão do TPA final e AMA final com o método de rotação: TPA(RT)f(%TPAd), TPA(RE)f(%TPAd), AMA(RT)f(%AMAzero), AMA(RE)f(%AMAzero) e o resultado de cada autor foram Hulse 10,0 ± 0,3(46,6%), 9,9 ± 0,1(60%), 0,3 ± 0,3(33,3%), 0,3 ± 0,3(13,3%), Osmond 10,1 ± 0,2(75%), 10,1 ± 0,2(83,3%), 0,4 ± 0,4(33,3%), 0,4 ± 0,3(8,3%), Miles 10,0 ± 0,1(66,6%), 10,0 ± 0,1(75%), 0,2 ± 0,1(16,6%), 0,2 ± 0,1(8,3%), Tudury 9,6 ± 0,6(31,2%), 9,5 ± 0,2(31,2%), 1,0 ± 0,7(18,7%), 1,0 ± 0,6(12,5%) respectivamente. O RT inicialmente descrito obteve um percentual maior de AMA em zero graus, portanto, o método RE é descartado para utilizá-lo como alternativa no planejamento CBLO