1,369 research outputs found
Underlying factors promoting nestedness of bird assemblages in cays of the Jardines de la Reina archipelago, Cuba
Factores subyacentes que promueven el anidamiento de ensamblajes de aves en cayos del archipiélago de los Jardines de la Reina, Cuba La evaluación de los factores asociados a los modelos de anidamiento se ha convertido en un aspecto esencial de los estudios sobre estructuración de comunidades. Los ensamblajes de aves del archipiélago de los Jardines de la Reina presentan una estructura anidada estable, aunque sus causas permanecen sin evaluar. Se elaboró una matriz de datos de presencia y ausencia a partir de un inventario de aves obtenido en 43 cayos de este archipiélago. Se calculó el anidamiento mediante el índice NODF basado en el relleno superpuesto y decreciente. La significación del anidamiento se evaluó mediante 1.000 iteraciones de cuatro modelos nulos. Las columnas de la matriz se reordenaron para evaluar siete factores que podrían estar relacionados con el anidamiento en las comunidades de aves. Los ensamblajes de aves presentaron un modelo de anidamiento significativo (67,93) y todos los factores contribuyeron (p < 0,01) a los modelos de anidamiento de las comunidades de aves. La diversidad de hábitats y el área y el perímetro de los cayos fueron los factores que más contribuyeron a la estructura anidada. El modelo de anidamiento de los ensamblajes de aves en los Jardines de la Reina podría estar causado por la interacción de la extinción selectiva y, en menor medida, por la colonización diferencial de especies.Factores subyacentes que promueven el anidamiento de ensamblajes de aves en cayos del archipiélago de los Jardines de la Reina, Cuba La evaluación de los factores asociados a los modelos de anidamiento se ha convertido en un aspecto esencial de los estudios sobre estructuración de comunidades. Los ensamblajes de aves del archipiélago de los Jardines de la Reina presentan una estructura anidada estable, aunque sus causas permanecen sin evaluar. Se elaboró una matriz de datos de presencia y ausencia a partir de un inventario de aves obtenido en 43 cayos de este archipiélago. Se calculó el anidamiento mediante el índice NODF basado en el relleno superpuesto y decreciente. La significación del anidamiento se evaluó mediante 1.000 iteraciones de cuatro modelos nulos. Las columnas de la matriz se reordenaron para evaluar siete factores que podrían estar relacionados con el anidamiento en las comunidades de aves. Los ensamblajes de aves presentaron un modelo de anidamiento significativo (67,93) y todos los factores contribuyeron (p < 0,01) a los modelos de anidamiento de las comunidades de aves. La diversidad de hábitats y el área y el perímetro de los cayos fueron los factores que más contribuyeron a la estructura anidada. El modelo de anidamiento de los ensamblajes de aves en los Jardines de la Reina podría estar causado por la interacción de la extinción selectiva y, en menor medida, por la colonización diferencial de especies.Assessing the factors associated with nestedness patterns is a crucial aspect in studies of community structure. Bird assemblages in the Jardines de la Reina archipelago have a stable nested structure but the underlying influences have not been evaluated. We constructed a presence–absence data matrix based on a bird inventory obtained from 43 cays of this archipelago. We calculated nestedness using the NODF metric based on the overlap and decreasing fill and evaluated its significance by running 1,000 iterations of four null models. The matrix columns were rearranged to evaluate seven factors possibly related to the nestedness of bird communities. Bird assemblages exhibited a significant nested pattern (67.93) and all factors contributed (p < 0.01) to the nestedness patterns of bird communities. Habitat diversity and cay area and perimeter were the factors that contributed most to the nested structure. The nestedness pattern in the bird assemblages of the Jardines de la Reina archipelago was potentially caused by the interaction of selective extinction and differential colonization of species, with the former having a more remarkable effect
Effects of migrations on the nestedness structure of bird assemblages in cays of the Jardines de la Reina archipelago, Cuba
Efecto de las migraciones sobre la estructura de anidamiento de los ensamblajes de aves en los cayos del archipiélago de los Jardines de la Reina, Cuba
La hipótesis del subgrupo anidado plantea que, en biotas fragmentadas, las especies de los sitios empobrecidos constituyen subconjuntos no aleatorios de las especies de los sitios con mayor riqueza. El efecto de las migraciónones sobre estos modelos aún no ha sido abordado plenamente. Se compararon los estados fenológico de la comunidad durante las migraciones primaveral y otoñal. Se recogieron datos sobre las presencias y ausencias de las especies de aves en 43 cayos del archipiélago de los Jardines de la Reina. Luego se construyeron dos matrices de incidencia para los periodos otoñal y primaveral. El grado de anidamiento de las matrices se calculó mediante el índice de anidamiento basado en el relleno superpuesto y decreciente, y se evaluó su significación mediante 1.000 réplicas de cuatro modelos nulos. Los ensamblajes de aves presentaron un mayor número de especies en el periodo otoñal (67) que en el primaveral (51). También manifestaron un modelo de anidamiento significativo y estable, que fue ligeramente mayor durante el periodo primaveral. Así, las fluctuaciones estacionales debidas a los movimientos migratorios prácticamente no alteraron la estructura anidada de los ensamblajes de aves.The nested subset hypothesis states that species in fragmented, less species–rich biotas are non–random subsets of those inhabiting richer sites. The effect of migration on these models has not been yet fully addressed. We compared the phenological stages of the community during the spring and fall migrations. Presence–absence data of bird species occurring at 43 cays of the Jardines de la Reina archipelago was compiled and two incidence matrices were built for fall and spring periods. The degree of nestedness was estimated based on the overlap and decreasing fill, and its significance was assessed by means of 1,000 replicates of four null models. Bird assemblages showed a higher number of species during fall (67) than they did in spring (51). They also showed a significant and stable pattern of nestedness, although this was slightly higher in spring. Seasonal fluctuations caused by migratory movements thus barely affected the nested structure of bird assemblages.Efecto de las migraciones sobre la estructura de anidamiento de los ensamblajes de aves en los cayos del archipiélago de los Jardines de la Reina, Cuba
La hipótesis del subgrupo anidado plantea que, en biotas fragmentadas, las especies de los sitios empobrecidos constituyen subconjuntos no aleatorios de las especies de los sitios con mayor riqueza. El efecto de las migraciónones sobre estos modelos aún no ha sido abordado plenamente. Se compararon los estados fenológico de la comunidad durante las migraciones primaveral y otoñal. Se recogieron datos sobre las presencias y ausencias de las especies de aves en 43 cayos del archipiélago de los Jardines de la Reina. Luego se construyeron dos matrices de incidencia para los periodos otoñal y primaveral. El grado de anidamiento de las matrices se calculó mediante el índice de anidamiento basado en el relleno superpuesto y decreciente, y se evaluó su significación mediante 1.000 réplicas de cuatro modelos nulos. Los ensamblajes de aves presentaron un mayor número de especies en el periodo otoñal (67) que en el primaveral (51). También manifestaron un modelo de anidamiento significativo y estable, que fue ligeramente mayor durante el periodo primaveral. Así, las fluctuaciones estacionales debidas a los movimientos migratorios prácticamente no alteraron la estructura anidada de los ensamblajes de aves
Omacetaxine may have a role in chronic myeloid leukaemia eradication through downregulation of Mcl-1 and induction of apoptosis in stem/progenitor cells
Chronic myeloid leukaemia (CML) is maintained by a rare population of tyrosine kinase inhibitor (TKI)-insensitive malignant stem cells. Our long-term aim is to find a BcrAbl-independent drug that can be combined with a TKI to improve overall disease response in chronic-phase CML. Omacetaxine mepesuccinate, a first in class cetaxine, has been evaluated by clinical trials in TKI-insensitive/resistant CML. Omacetaxine inhibits synthesis of anti-apoptotic proteins of the Bcl-2 family, including (myeloid cell leukaemia) Mcl-1, leading to cell death. Omacetaxine effectively induced apoptosis in primary CML stem cells (CD34<sup>+</sup>38<sup>lo</sup>) by downregulation of Mcl-1 protein. In contrast to our previous findings with TKIs, omacetaxine did not accumulate undivided cells <i>in vitro</i>. Furthermore, the functionality of surviving stem cells following omacetaxine exposure was significantly reduced in a dose-dependant manner, as determined by colony forming cell and the more stringent long-term culture initiating cell colony assays. This stem cell-directed activity was not limited to CML stem cells as both normal and non-CML CD34<sup>+</sup> cells were sensitive to inhibition. Thus, although omacetaxine is not leukaemia stem cell specific, its ability to induce apoptosis of leukaemic stem cells distinguishes it from TKIs and creates the potential for a curative strategy for persistent disease
Assessing an E- learning and B- Learning Model: a Study of Perceived Satisfaction
Comunicação apresentada na 7ª Conferência ICERI, 17-19 novembro de 2014, Sevilha, Espanh
Adnexal Torsion
Adnexal torsion is a rare event whose diagnosis requires a high degree of suspicion since its presentation is clinical and laboratory nonspecific. Ultrasound constitute the first-line exam in the imaging evaluation and timely surgical treatment, with
detorsion, is mandatory to allow the preservation of the structures involved. The effectiveness of preventive measures of
recurrence is yet to be determined.
In this paper, in addition to a literature review, the authors present a new imaging finding and propose a flowchart for
therapeutic decision
Psychological effects of gamified didactics with exergames in Physical Education at primary schools: Results from a natural experiment
The physical effects of exergaming have been proven, but less is known about the psychological effects in elementary schools that make exergames an effective educational tool. The application of gamification to education is still an emerging practice that has been barely studied. The aim of this study was to analyse the effects of a gamified exergaming intervention in Physical Education classes in primary schools on psychological variables like motivation, flow, basic psychological needs and academic performance. A natural experiment with a non-randomised controlled design was run. The participants were recruited from four schools (n = 417), and received traditional didactic intervention or a gamified exergaming intervention. Both lasted 1 month. The results showed better positive gamified exergaming effects on basic psychological needs, academic performance and some flow dimensions. No interaction effects were found in intrinsic motivation, external regulation and amotivation, although specific improvements in the gamified exergaming group are discussed. The Mechanics-Dynamics-Aesthetics gamification model and the Just Dance Now exergame may be resources capable of producing positive psychological effects on school-based Physical Education
Transport mechanism of macromolecules on hydrophilic bio-polymeric matrices : diffusion of protein-based compounds from chitosan films
The transport mechanism of protein-based bioactive compounds (a peptide fraction from whey protein concentrate, glycomacropeptide and lactoferrin), from chitosan films to liquid medium, was studied. Mathematical models were used to discuss the transport mechanism. Data from release experiments was successfully described by a model which accounts for both Fick and Case II transport – the linear superimposition model. Results show that the mechanism of transport and the effect of temperature and peptide type could be related with physical properties of chitosan films where the tested bioactive compounds were incorporated. The approach presented here allows interpretation of the phenomena involved in mass transport in the systems studied and, once extended to other systems, may contribute to an understanding of transport in hydrophilic bio-polymeric matrices.This work was supported by Fundacao para a Ciencia e a Tecnologia through project PTDC/AGR/ALI/67194/2006. Authors Ana C. Pinheiro, Ana I. Bourbon and Mafalda A.C. Quintas gratefully acknowledge their Grants SFRH/BD/48120/2008, SFRH/BD/73178/2010 and SFRH/BPD/41715/2007, respectively
Information system for tablet identification (ISTI)
Poster presented at the 4th International Congress of CiiEM - "Health, Well-being and Ageing in the XXI Century. 2-5 June 2019, Campus Egas Moniz, Monte de Caparica, PortugalN/
Positive attitudes towards racquet sport of primary school teachers
The aim of this study was to know the attitudes towards racquet sports in Spanish primary school teachers. Eighty one teachers from Zaragoza participated in this study, filling out the scale Positive attitudes towards racquet sport of the validated Table Tennis Attitudes Questionnaire. The internal consistency of this scale was measured with the Cronbach alpha coefficient. The results indicate Md=2.19 (SD=0.38) in this scale. The 27.2% of the teachers have never done one training course of this kind of sports, being the badminton the most studied sport. However, the teachers have mainly badminton teaching material. This study shows which is the prevalence of the racquet sports in the teacher programs. Statistically significant relationships were found between the studies of the teachers or the kind of the school, and the attitudes towards racquet sport. The results of this study suggest us that there have to be more educative programs to implementation racquet sports
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