Continuous assessment activities - correlation with final exam grades and effect on final grades. A business studies experience

In this paper we analyze the partial grades – of continuous assessment activities including the final exam – and the final grades – computed as a weighted average of partial grades – for nine subjects taught in the third year of Business Administration Degree. On one hand, results show that there is a significant positive correlation between the grades of continuous assessment activities (excluded the final exam) and final exam in seven subjects. On the other hand, overall we find that students’ grades in continuous assessment activities (excluded the final exam) help in the improvement of their final grades (i.e., students’ final grades exceed the grades that they would obtain by only taking into account their final exam grades). The results are consistent when the analysis is carried out over each subject area as well as over the grades of the students who registered for the nine subjects.

Revisión sistemática de la producción española sobre rendimiento académico entre 1980 y 2011

El bajo rendimiento académico sigue siendo un problema de investigación de gran impacto social. Sin embargo, los resultados científicos no están teniendo repercusión en la mejora, ni en las políticas educativas. En este trabajo nos propusimos identificar, ordenar, analizar y extraer conclusiones sobre la producción española sobre rendimiento académico, con el fin de visualizarla y derivar problemas futuros objeto de investigación. Para ello se llevó a cabo un estudio de revisión en seis etapas, en el que se combinaron procedimientos metodológicos de investigación de síntesis y de investigación bibliométrica. Se identificaron las publicaciones en cuatro bases de datos españolas; posteriormente se analizaron y codificaron los datos extraídos alrededor de nueve indicadores: título, año, tipo de documento, editorial, autor, número autores, institución, comunidad autónoma y tema. Los resultados muestran una producción constante y creciente (1595 referencias), pero dispersa, tanto por el inmenso número de autores que publican, la mayoría con un solo trabajo, como por los lugares donde publican. Las temáticas más tratadas se refieren en primer lugar a modelos explicativos, diagnóstico y tratamiento; en segundo lugar se abordan los factores y variables determinantes del bajo y alto rendimiento académico; en tercer lugar se desarrollan estudios sobre legislación y de otras variables psicológicas y educativas en relación con el rendimiento. Este estudio supone una aproximación sintetizada de la producción sobre rendimiento académico en España, y un primer paso para investigaciones de síntesis posteriores, que nos permitan identificar buenas prácticas para el ejercicio de “prácticas basadas en la evidencia”, y otros problemas de investigación.

Social networks applied to training

In this article, we address the importance and relevance that social networks exhibit in their use as an educational resource.  This relevance relies in the possibility of implementing new learning resources or increasing the level of the participant's connectivity, as well as developing learning communities.  Also, the risk entailed from their use is discussed, especially for the students that have a low technological education or those having excessive confidence on the media.  It is important to highlight that the educational use of social networks is not a simple extension or translation of the student's habitual, recreational use, but that it implies an important change in the roles given to teachers as well as learners; from accommodative learning environments that only encourage memorization to other environments that demand an active, reflective, collaborative and proactive attitude, that require the development/acquisition of technological as well as social abilities, aptitudes and values.  It is also important to highlight that a correct implementation and adequate use will not only foment formal learning, but also informal and non-formal learning.

Mole-rats from higher altitudes have greater thermoregulatory capabilities

Subterranean mammals (those that live and forage underground) inhabit a challenging microenvironment, with high levels of carbon dioxide and low levels of oxygen. Consequently, they have evolved specialised morphological and physiological adaptations. For small mammals that inhabit high altitudes, the effects of cold are compounded by low oxygen partial pressures. Hence, subterranean mammals living at high altitudes are faced with a uniquely demanding physiological environment, which presumably necessitates additional physiological adjustments. We examined the thermoregulatory capabilities of two populations of Lesotho mole-rat Cryptomys hottentotus mahali that inhabit a 'low' (1600 in) and a 'high' (3200 m) altitude. Mole-rats from the high altitude had a lower temperature of the lower critical point, a broader thermoneutral zone, a lower thermal conductance and greater regulatory non-shivering thermogenesis than animals from the lower altitude. However, minimum resting metabolic rate values were not significantly different between the populations and were low compared with allometric predictions. We suggest that thermoregulatory costs may in part be met by animals maintaining a low resting metabolic rate. High-altitude animals may adjust to their cooler, more oxygen-deficient environment by having an increased non-shivering thermogenesis whilst maintaining low thermal conductance. (c) 2006 Elsevier Inc. All rights reserved.

Huddling in groups leads to daily energy savings in free-living African Four-Striped Grass Mice, Rhabdomys pumilio

1. Free-living animals make complex decisions associated with optimizing energy and nutrient intake. In environments where ambient temperatures fall below the thermoneutral zone, homeotherms must choose whether or not to forage, how long and what to forage for, and whether or not to perform activities that conserve energy.

Seasonal energetics of the Hottentot golden mole at 1500m altitude

Winter is an energetically stressful period for small mammals as increasing demands for thermoregulation are often coupled with shortages of food supply. In sub-tropical savannah, Hottentot golden moles (Ambysomus hottentottus longiceps) forage throughout the year and for lone periods of each day. This may enable them to acquire sufficient resources from an insectivorous prey base that is both widely dispersed and energetically costly to obtain. However, they also inhabit much cooler regions; how their energy budgets are managed in these areas is unknown. We measured the daily energy expenditure (DEE), resting metabolic rate (RMR) and water turnover (WTO) of free-living golden moles during both winter and summer at high altitude (1500 m). We used measurements of deuterium dilution to estimate body fat during these two periods. DEE, WTO and body mass did not differ significantly between seasons. However, RMR values were higher during the winter than the summer and, in the latter case were also lower than allometric predictions. Body fat was also higher during the winter. Calculations show that during the winter they may restrict activity to shorter, more intense periods. This, together with an increase in thermal insulation, might enable them to survive the cold. (c) 2005 Elsevier Inc. All rights reserved.

"Bobok" y "Pedro Páramo", dos narraciones sobre muertos

El presente estudio realiza un análisis comparativo entre la novela del mexicano Juan Rulfo, Pedro Páramo (1955), y un cuento del escritor ruso Dostoievski que trata también el tema del Más allá, titulado Bobok (1873). Paralelamente, se trabaja con la posibilidad de que el relato ruso hubiese podido ser una más de las fuentes literarias de la novela mexicana, y se trata de determinar las posibles conexiones -directas o indirectas- entre las dos obras. Ambas son puestas en común por su género literario, y a partir de ahí se estudian los elementos constitutivos que tienen en común, sus afinidades y divergencias más llamativas.

Burrow architecture and digging activity in the Cape dune mole rat

While females are traditionally thought to invest more time and energy into parental care than males, males often invest more resources into searching and displaying for mates, obtaining mates and in male-male conflict. Solitary subterranean mammals perform these activities in a particularly challenging niche, necessitating energetically expensive burrowing to both search for mates and forage for food. This restriction presumably affects males more than females as the former are thought to dig longer tunnels that cover greater distances to search for females. We excavated burrow systems of male and female Cape dune mole rats Bathyergus suillus the, largest truly subterranean mammal, to investigate whether male burrows differ from those of females in ways that reflect mate searching by males. We consider burrow architecture (length, internal dimensions, fractal dimension of tunnel systems, number of nesting chambers and mole mounds on the surface) in relation to mating strategy. Males excavated significantly longer burrow systems with higher fractal dimensions and larger burrow areas than females. Male burrow systems were also significantly farther from one another than females were from other females' burrow systems. However, no sex differences were evident in tunnel cross-sectional area, mass of soil excavated per mound, number of mounds produced per unit burrow length or mass of soil excavated per burrow system. Hence, while males may use their habitat differently from females, they do not appear to differ in the dimensions of the tunnels they create. Thus, exploration and use of the habitat differs between the sexes, which may be a consequence of sex differences in mating behaviour and greater demands for food.

Tracking leatherback turtles (Dermochelys coriacea) during consecutive inter-nesting intervals: Further support for direct transmitter attachment

Over recent years there have been substantial efforts to record and interpret the post-nesting movements of leatherback turtles (Dermochelys coriacea) breeding in tropical regions. Less well documented are the movements undertaken by individual turtles during the breeding season itself, or more specifically between sequential nesting events. Such movements are of interest for two reasons: (1) gravid female leatherbacks may range extensively into the territorial waters and nesting beaches of neighbouring countries, raising questions for conservationists and population ecologists; and (2) the magnitude of movements themselves help elucidate underlying reproductive strategies (e.g. whether to rest near to the nesting or forage extensively). Here, satellite relay data loggers are used (SRDLs) to detail the movements and behaviour of two female leatherback turtles throughout three consecutive inter-nesting intervals in the Commonwealth of Dominica, West Indies. Both near-shore residence and extensive inter-nesting movements were recorded, contrasting previous studies, with movements away from the nesting beach increasing towards the end of the nesting season. Using this behavioural study as a backdrop, the suitability of attaching satellite transmitters directly to the carapace was additionally explored as an alternative approach to conventional harness deployments. Specifically, the principal aims were to (1) gather empirical data on speed of travel and (2) assess dive performance (aerobic dive limit) to enable comparisons with turtles previously fitted with harnesses elsewhere in the Caribbean (n = 6 turtles; Grenada, WI). This produced mixed results with animals bearing directly attached transmitters travelling significantly faster (55.21 km day(-1): SD 6.68) than harnessed individuals (39.80 km day(-1); SD 6.19); whilst no discernable difference in dive performance could be found between the two groups of study animals. (C) 2009 Elsevier B.V. All rights reserved.

Exploitation of intertidal Zostera species by Brent geese (Branta bernicla hrota): Why dig for your dinner?

Exploitation of intertidal Zostera spp by Pale-bellied Brent geese Branta bernicla hrota in Strangford Lough, Co. Down, was studied with respect to feeding method employed, plant parts exploited, the quality of the forage, and assimilation efficiency. Most Brent geese feeding activity involved digging behaviour, which, along with faecal analyses, indicated that birds were exploiting above (shoot) and below ground portions (rhizome) of the food plant. Nutritional information indicated that while rhizome was lower in overall energy, it contained more accessible energy in the form of water soluble carbohydrate and was lower in indigestible fibre than shoot. Feeding experiments indicated that Brent geese feeding on whole plants of Zostera noltii achieved 43% assimilation efficiency. Dig feeding of intertidal Zostera spp by Brent geese is likely to significantly increase the amount and quality of the forage available. Why dig feeding is not employed on all intertidal systems, and its potential effects on the food plants are discussed.

Emergence time and foraging activity in Pallas' mastiff bat, Molossus molossus (Chiroptera: Molossidae) in relation to sunset/sunrise and phase of the moon

The decision on when to emerge from the safety of a roost and forage for prey is thought to be a result of the trade off between peak insect abundance and predation pressure for bats. In this study we show that the velvety free-tailed bat Molossus molossus emerges just after sunset and just before sunrise for very short foraging bouts (average 82.2 min foraging per night). Contrary to previous studies, bats remain inactive in their roost between activity patterns. Activity was measured over two complete lunar cycles and there was no indication that phase of the moon had an influence on emergence time or the numbers of bats that emerged from the roost. This data suggests that M. molossus represents an example of an aerial hawking bat whose foraging behaviour is in fact adapted to the compromise between the need to exploit highest prey availability and the need to avoid predation.

The prediction of intake potential and organic matter digestibility of grass silages by near infrared spectroscopy analysis of undried samples

A study was undertaken to examine a range of sample preparation and near infrared reflectance spectroscopy (NIPS) methodologies, using undried samples, for predicting organic matter digestibility (OMD g kg(-1)) and ad libitum intake (g kg(-1) W-0.75) of grass silages. A total of eight sample preparation/NIRS scanning methods were examined involving three extents of silage comminution, two liquid extracts and scanning via either external probe (1100-2200 nm) or internal cell (1100-2500 nm). The spectral data (log 1/R) for each of the eight methods were examined by three regression techniques each with a range of data transformations. The 136 silages used in the study were obtained from farms across Northern Ireland, over a two year period, and had in vivo OMD (sheep) and ad libitum intake (cattle) determined under uniform conditions. In the comparisons of the eight sample preparation/scanning methods, and the differing mathematical treatments of the spectral data, the sample population was divided into calibration (n = 91) and validation (n = 45) sets. The standard error of performance (SEP) on the validation set was used in comparisons of prediction accuracy. Across all 8 sample preparation/scanning methods, the modified partial least squares (MPLS) technique, generally minimized SEP's for both OMD and intake. The accuracy of prediction also increased with degree of comminution of the forage and with scanning by internal cell rather than external probe. The system providing the lowest SEP used the MPLS regression technique on spectra from the finely milled material scanned through the internal cell. This resulted in SEP and R-2 (variance accounted for in validation set) values of 24 (g/kg OM) and 0.88 (OMD) and 5.37 (g/kg W-0.75) and 0.77 (intake) respectively. These data indicate that with appropriate techniques NIRS scanning of undried samples of grass silage can produce predictions of intake and digestibility with accuracies similar to those achieved previously using NIRS with dried samples. (C) 1998 Elsevier Science B.V.

Arsenic residues in predatory birds from an area of Britain with naturally and anthropogenically elevated arsenic levels

Birds of prey forage over large areas and so might be expected to accumulate contaminants which are elevated but heterogeneously distributed in the general environment. The aim of this study was to test the hypothesis that arsenic levels in raptors from a region with elevated environmental arsenic concentrations were higher than those in birds from an uncontaminated part of Britain. Arsenic concentrations in the liver, kidney and muscle of kestrels, Falco tinnunculus, sparrowhawks, Accipiter nisus, and barn owls, Tyto alba, from south-west (SW) England, an area with naturally and anthropogenically (through mining) elevated environmental arsenic concentrations, were compared with those in birds from SW Scotland, where no such geochemical anomaly exists. Arsenic residues in kestrels from SW England were approximately three times greater than those in birds from SW Scotland for the three tissue types analysed. This was not the case for the other species in which arsenic residues were similar in birds from both regions. It is suggested that differences between species in both diet and arsenic metabolism could explain why kestrels have elevated arsenic tissue burdens in response to general environmental contamination but sparrowhawks and barn owls do not.

Range expansion and comparative habitat use of insular, congeneric lagomorphs: invasive European hares Lepus europaeus and endemic Irish hares Lepus timidus hibernicus

The European hare (Lepus europaeus) has declined throughout its native range but invaded numerous regions where it has negatively impacted native wildlife. In southern Sweden, it replaces the native mountain hare (L. timidus) through competition and hybridisation. We investigated temporal change in the invasive range of the European hare in Ireland, and compared its habitat use with the endemic Irish hare (L. timidus hibernicus). The range of the European hare was three times larger and its core range twice as large in 2012–2013 than in 2005. Its rate of radial range expansion was 0.73 km year−1 with its introduction estimated to have occurred ca. 1970. Both species utilised improved and rough grasslands and exhibited markedly similar regression coefficients with almost every land cover variable examined. Irish hares were associated with low fibre and high sugar content grass (good quality grazing) whilst the invader had a greater tolerance for low quality forage. European hares were associated with habitat patch edge density, suggesting it may be more suited to using hedgerows as diurnal resting sites than the Irish hare. Consequently, the invader had a wider niche breadth than the native but their niche overlap was virtually complete. Given the impact of the European hare on native species elsewhere, and its apparent pre-adaption for improved grasslands interspersed with arable land (a habitat that covers 70 % of Ireland), its establishment and range expansion poses a significant threat to the ecological security of the endemic Irish hare, particularly given their ecological similarities.