30 research outputs found

    Shape-shifting and pushing against the odds: staff perceptions of the experiences of first generation students in South Africa and the UK

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    The principles of diversity and inclusion are valued across the higher education sector, but the ways in which these principles are translated into pedagogic practice are not always evident. Students who are first in their family to attend university continue to report barriers to full participation in university life. They are more likely to leave their studies early, and to achieve lower grades in their final qualifications, than students whose families have previous experience of higher education. The purpose of this study was to explore whether a mismatch between staff perceptions and students’ experiences might be a possible contributor to these disparities. The study explored and compared staff discourses about the experiences of first generation students at two universities, one in the United Kingdom (UK), and the other in South Africa (SA). One-to-one interviews were carried out with 40 staff members (20 at each institution) to explore their views about first generation students. The results showed that staff were well aware of challenges faced by first generation students; however, they were unsure of their roles in relation to shaping an inclusive environment, and tended not to consider how to use the assets that they believed first generation students bring with them to higher education. This paper explores these staff discourses; and considers proposals for challenging commonly-voiced assumptions about students and university life in a broader context of diversity and inclusive teaching practice

    Rapportages op grond van de Europese Vogelrichtlijn en Habitatrichtlijn : evaluatie rapportageperiode 2007-2012 en aanbevelingen voor de periode 2013-2018

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    In dit rapport wordt op grond van een evaluatie van de afgelopen rapportageperiode (2007-2012) een advies gegeven aan het Ministerie van Economische zaken hoe te anticiperen op de volgende rapportageperiode (2013-2018). Dit betreft de rapportages op grond van de Europese Vogelrichtlijn en Habitatrichtlijn, en specifiek de rapportageonderdelen waar ecologische kennis en informatie voor vereist is. Aanbevelingen worden gedaan voor het rapportageproces (proces), de beschikbaarheid en kwaliteit van data, informatie en kennis (inhoud) en de technische voorzieningen om het rapportageproces te ondersteunen (techniek). Beweegredenen om de desbetreffende aanbevelingen door te voeren, zijn het verhogen van de efficiency van het rapportageproces, de doorwerking van beleid en de kwaliteit van de beleidsinformatie

    Multi-species population indices for sets of species including rare, disappearing or newly occurring species

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    NI is funded by Natural Environment Research Council award NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability.Multi-species indices (MSI) are widely used as ecological indicators and as instruments to inform environmental policies. Many of these indices combine species-specific estimates of relative population sizes using the geometric mean. Because the geometric mean is not defined when values of zero occur, usually only commoner species are included in MSIs and zero values are replaced by a small non-zero value. The latter can exhibit an arbitrary influence on the geometric mean MSI. Here, we show how the compound Poisson and the negative binomial model can be used in such cases to obtain an MSI that has similar features to the geometric mean, including weighting halving and doubling of a species’ population equally. In contrast to the geometric mean, these two statistical models can handle zero values in population sizes and thus accommodate newly occurring and temporarily or permanently disappearing species in the MSI. We compare the MSIs obtained by the two statistical models with the geometric mean MSI and measure sensitivity to changes in evenness and to population trends in rare and abundant species. Additionally, we outline sources of uncertainty and discuss how to measure them. We found that, in contrast to the geometric mean and the negative binomial MSI, the compound Poisson MSI is less sensitive to changes in evenness when total abundance is constant. Further, we found that the compound Poisson model can be influenced more than the other two methods by trends of species showing a low interannual variance. The negative binomial MSI is less sensitive to trends in rare species compared with the other two methods, and similarly sensitive to trends in abundant species as the geometric mean. While the two new MSIs have the advantage that they are not arbitrarily influenced by rare, newly appearing and disappearing species, both do not weight all species equally. We recommend replacing the geometric mean MSI with either compound Poisson or negative binomial when there are species with a population size of zero in some years having a strong influence on the geometric mean MSI. Further, we recommend providing additional information alongside the MSIs. For example, it is particularly important to give an evenness index in addition to the compound Poisson MSI and to indicate the number of disappearing and newly occurring species alongside the negative binomial MSI.Publisher PDFPeer reviewe

    Viability of meta-populations of wetland birds in a fragmented landscape: Testing the key-patch approach

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    The key patch approach assumes that metapopulations in fragmented landscapes are likely to be viable with at least one "key" sub-population that is sufficiently large to ensure re-colonization of surrounding minor habitat patches. It is based on a minimum viable number of breeding pairs and within-breeding season dispersal distance, linked to size of the animal and longevity. It was tested using census data of 15 wetland bird species (bearded tit, bluethroat, great reed warbler, sedge warbler, Savi's warbler, grasshopper warbler, spotted crake, water rail, common snipe, common teal, garganey, little bittern, night heron, great bittern and marsh harrier) in 14 wetland complexes of variable size (3-55 k

    Jasmonic Acid-Induced Changes in Brassica oleracea Affect Oviposition Preference of Two Specialist Herbivores

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    Jasmonic acid (JA) is a key hormone involved in plant defense responses. The effect of JA treatment of cabbage plants on their acceptability for oviposition by two species of cabbage white butterflies, Pieris rapae and P. brassicae, was investigated. Both butterfly species laid fewer eggs on leaves of JA-treated plants compared to control plants. We show that this is due to processes in the plant after JA treatment rather than an effect of JA itself. The oviposition preference for control plants is adaptive, as development time from larval hatch until pupation of P. rapae caterpillars was longer on JA-treated plants. Total glucosinolate content in leaf surface extracts was similar for control and treated plants; however, two of the five glucosinolates were present in lower amounts in leaf surface extracts of JA-treated plants. When the butterflies were offered a choice between the purified glucosinolate fraction isolated from leaf surface extracts of JA-treated plants and that from control plants, they did not discriminate. Changes in leaf surface glucosinolate profile, therefore, do not seem to explain the change in oviposition preference of the butterflies after JA treatment, suggesting that as yet unknown infochemicals are involved

    The effect of nutrients on pyrrolizidine alkaloids in Senecio plants and their interactions with herbivores and pathogens

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    The aim of this review is to combine the knowledge of studies on effects of nutrients on pyrrolizidine alkaloids (PAs) in Senecio with those studies of effects of PAs on herbivores and pathogens in order to predict the effects that nutrients may have on herbivores and pathogens via changes in PAs. We discuss whether these predictions match with the outcome of studies where the effect of nutrients on herbivores and insects were measured. PA concentrations in S. jacobaea, S. vulgaris and S. aquaticus were mostly reduced by NPK fertilization, with genotype-specific effects occurring. Plant organs varied in their response to increased fertilization; PA concentrations in flowers remained constant, while shoot and roots were mostly negatively affected. Biomass change is probably largely responsible for the change in concentrations. Nutrients affect both the variety and the levels of PAs in the plant. The reduced PA concentrations after NPK fertilization was expected to benefit herbivores, but no or negative responses from insect herbivores were observed. Apparently other changes in the plant after fertilization are overriding the effect of PAs. Pathogens do seem to benefit from the lower PA concentrations after fertilization; they were more detrimental to fertilized plants than to unfertilized control plants. Future studies should include the effect of each element of nutrients separately and in combinations in order to gain more insight in the effect of specific nutrients on PA content in Senecio plants

    Isozymvariatie bij de soort Agrostis stolonifera L.

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    In vier, in hun milieu contrasterende populaties van Agrostis stolonifera L. werd de isozymvariatie voor zes enzymsystemen (GPI, EST, PGM, 6—PGD, ADH, IDH) bepaald. Het aantal verschillende isozymfenotypen in de vier populaties bleek groot te zijn. Slechts Ă©Ă©n van de 127 gevonden fenotypen kwam in twee populaties voor. Alle andere fenotypen kwamen hooguit in Ă©Ă©n van de populaties voor. Er is geen relatie gevonden tussen milieufactoren en isozymvariatie, wat aangeeft dat de onderzochte enzymsystemen selectief neutraal zijn. De polymorfie-indices waren in de vier populaties ongeveer even groot. Het aantal verschillende isozymfenotypen was in Ă©Ă©n populatie veel lager dan in de andere drie. De oorzaak hiervan is waarschijnlijk de sterkere kloonvorming in die populatie. Deze geringe mate van genetische variatieals gevolg van kloonvorming kan gedeeltelijk gecompenseerd worden door genetische variatie (in de vorm van p1odie-verschil1eh) binnen klonen. Ook temporele isozymvariatie kwam aan het licht. De ADH-fenotypen bleken bij de tweede electroforese meestal anders te zijn dan bij de eerste electroforese. De meest waarschijnlijke verklaring hiervoor is verandering van de ADH-expressie onder invloed van het milieu in de kas waarin de planten groeiden. Een mechanisme waardoor ook isozymvariatie binnen klonen en binnen individuele planten mogelijk is wordt besproken.

    Towards a new generation of breeding bird Atlases: annual Atlases based on site-occupancy models

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    Site-occupancy models which take into account detection probability of species have promising applications for Atlas work. These models enable to estimate the ‘true’ state of occupancy in sites even if sites differ in observation effort. Data collected with different field methods and opportunistic data collected without standardized field methods may be used together to derive reliable inferences on species distribution, colonisation and extinction. This may lead to a new generation of atlases with annual distribution maps on the internet. We emphasize the remarkable perspectives of these models and discuss some problems that need to be solved
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