2,753 research outputs found
Role of functionally dominant species in varying environmental regimes: evidence for the performance-enhancing effect of biodiversity
Background Theory suggests that biodiversity can act as a buffer against disturbances and environmental variability via two major mechanisms: Firstly, a stabilising effect by decreasing the temporal variance in ecosystem functioning due to compensatory processes; and secondly, a performance enhancing effect by raising the level of community response through the selection of better performing species. Empirical evidence for the stabilizing effect of biodiversity is readily available, whereas experimental confirmation of the performance-enhancing effect of biodiversity is sparse. Results Here, we test the effect of different environmental regimes (constant versus fluctuating temperature) on bacterial biodiversity-ecosystem functioning relations. We show that positive effects of species richness on ecosystem functioning are enhanced by stronger temperature fluctuations due to the increased performance of individual species. Conclusions Our results provide evidence for the performance enhancing effect and suggest that selection towards functionally dominant species is likely to benefit the maintenance of ecosystem functioning under more variable conditions
A meta analysis of effectiveness of E interventions to reduce alcohol consumption in college and university students
Objective: To evaluate the effectiveness and moderators of E-Interventions versus assessment only (AO) controls in the reduction of alcoholic drinks per week (DPW) in university students.
Study design and methods: Cochrane library, CINAEL, ERIC, MEDLINE, PsycINFO, PubMed, and Web of Science were searched up to June 2017. Studies were included if they were: an RCT, assessed the effectiveness of E-Interventions at reducing DPW, and employed university/college students. 23 studies (N = 7,614) were included and quality was assessed using the JADAD scale.
Results: Weighted mean effect sizes were calculated using random-effects models. These showed a small, significant effect of E-Interventions at reducing the number of alcoholic DPW. Moderator analysis found a significant advantage for web-based personalised feedback interventions compared to other E-Interventions.
Conclusions: E-Interventions show a small, significant effect at reducing mean alcoholic DPW. Personalised feedback E-Interventions showed the strongest effect
Dynamical phase transition of a 1D transport process including death
Motivated by biological aspects related to fungus growth, we consider the
competition of growth and corrosion. We study a modification of the totally
asymmetric exclusion process, including the probabilities of injection
and death of the last particle . The system presents a phase transition
at , where the average position of the last particle
grows as . For , a non equilibrium stationary state
exists while for the asymptotic state presents a low density
and max current phases. We discuss the scaling of the density and current
profiles for parallel and sequential updates.Comment: 4 pages, 5 figure
An outside-inside view of exclusive practice within an inclusive mainstream school
This article is a reflection on a sabbatical experience in a mainstream school where an inclusive ethos underpinned the curriculum and environmental approaches for all children. The period as Acting Head teacher raised some challenges for me in reconciling inclusion for all children and the exclusive nature of some professional and physical spaces available to the community of adults working in the school. It has highlighted some development opportunities for the senior management of the school and its governing body
Social partners’ bargaining strategies in Germany and Spain after the introduction of the Euro: a morphogenetic perspective on corporate agency
This article addresses how far wage imbalances in the Eurozone can be imputable to intentional agency by collective bargaining organisations. Using Archer’s morphogenetic approach, we explain the agentic role of social partners in core (Germany) and periphery (Spain) cases, in relation with the respective collective bargaining regimes. We show that the capacity of macro- and meso-level organisations to effect wage-setting practices can be constrained inadvertently by contextual influences with morphostatic properties, generating constrained modes of corporate agency. Yet wage moderation is best understood as a form of agency itself, functioning ‘by being’ rather than ‘doing’, which over time can become more innovative. We contrast this finding with the less constrained capacity of more institutionalized corporate agents, such as transnational business corporations and central state agencies
Decay of the Relative Error in the Formation of Acoustic Bullets
In a previous paper, the authors showed how to construct certain solutions of the acoustic and electromagnetic wave equations in three dimensions, which are constrained asymptotically to a narrow conical sector of an outgoing spherical shell, i.e., which behave like “bullets.” In this paper, it is shownthat, in the acoustic case, the magnitude of the relative error between the true solution and its asymptotic form decays in time according to an inverse square root law. Read More: https://epubs.siam.org/doi/10.1137/015302
Tracked vehicle effects on vegetation and soil characteristics
A 3-year experiment to evaluate tracked vehicle effects on vegetation and soil characteristics was established on the Gilbert C. Grafton South State Military Reservation (CGS) in North Dakota. Study objectives were to evaluate the effects of 3 tracked vehicle use intensity treatments on plant species cover and frequency, and soil compaction. The 3 treatments evaluated include heavy use (74 passes), moderate use (37 passes) and no use. The moderate use treatment represents a typical use of 1 battalion unit at CGS with the heavy use treatment classified as 2 battalion units. This land area comprised a 50 by 150 meter block subdivided into three, 50 by 50 meter blocks. Each 50 by 50 meter block was subdivided into three, 16.7 by 50 meter blocks with each block treated with 1 of the 3 treatments. Soil bulk density increased (P \u3c 0.05) on the moderate and heavy use treatments in the 0 to 15, 30 to 45, and 45 to 60 cm soil depths. Kentucky bluegrass (Poa pratensis L.) cover (P \u3c 0.05) decreased in 1996 on both the moderate and heavy use treatments but was not (P \u3e 0.05) different among all treatments in 1997. The tracked vehicle use on the heavy and moderate treatments did not change species composition or litter amounts after 2 years; however, bulk density and bare ground increased on both treatments in 1996 and 1997.
Se establecio un experimento de 3 aiios en la Reservacion Militar Estatal Gilbert C. Grafon (CGS) de North Dakota para evaluar los efectos del paso de vehaiculos militares en la vegetacion y suelo. Los objetivos del estudio fueron evaluar los efectos de 3 intensidades de paso de vehaiculos militares en la cobertura y frecuencia de especies vegetales y la compactacion del suelo. Los 3 tratamientos evaluados fueron: uso alto (74 pasos), uso moderado (37 pasos) y sin uso. El uso moderado representa el uso taipico de una unidad de batallon en el CGS y el tratamiento de uso alto representa el paso de dos unidades de batallon. El aea experimental fue un bloque de 50 x 150 m dividido en tres bloques, cada bloque de 50 x 50 m se subdividido en 3 bloques de 16.7 x 50 m y en cada uno de estos bloque se aplico uno de los tratamientos. La densidad aparente del suelo a las profundidades de 0-15, 30-45 y 45-60 cm aumento (P \u3c 0.05) en los tratamientos de uso moderado y alto. En 1996, la cobertura del zacate Kentucky bluegrass (Poa pratensis L.) disminuyo (P \u3c 0 .05) en los tratamientos de uso moderado y alto, pero en 1997 la cobertura de esta especie no difirio entre tratamientos (P \u3e 0.05). Despues de 2 anios, el uso moderado y alto de vehaiculos militares no cambio la composicion de especies ni la cantidad de mantillo; sin embargo, la densidad aparente y el suelo desnudo aumento en ambos tratamientos en 1996 y 1997
Changing assessment practice in engineering: how can understanding lecturer perspectives help?
Assessment in engineering disciplines is typically oriented to demonstrating competence in specific tasks. Even where assessments are intended to have a formative component, little priority may be given to feedback. Engineering departments are often criticized, by their students and by external quality reviewers, for paying insufficient attention to formative assessment. The e3an project set out to build a question bank of peer-reviewed questions for use within electrical and electronic engineering. As a part of this process, a number of engineers from disparate institutions were required to work together in teams, designing a range of assessments for their subject specialisms. The project team observed that lecturers were especially keen to develop formative assessment but that their understanding of what might be required varied considerably. This paper describes the various ways in which the processes of the project have engaged lecturers in actively identifying and developing their conceptions of teaching, learning and assessment in their subject. It reports on an interview study that was conducted with a selection of participants. It is concluded that lecturers' reflections on and understanding of assessment are closely related to the nature of the subject domain and that it is essential when attempting to improve assessment practice to start from the perspective of lecturers in the discipline
‘You see similarities more than differences after a while’. Communities of Practice in European industrial relations. The case of the hospital European Sectoral Social Dialogue
This article looks at the hospital European Sectoral Social Dialogue Committee (SSDC) through a Community of Practice (CoP) theoretical lens. Based on a 2-year project, qualitative in-depth interviews at the European level and in five Member states, and participant observation of the hospital SSDC, we propose a shift from traditional institutional and resource-based accounts and provide a learning and knowledge-focused understanding of this specific area of European industrial relations. Interpreting the SSDCs as a CoP sheds new light on the role of power relations, participation and informal activities among members and on how they work together; this, we find, can alert those interested in more effective functioning of the European Sectoral Social Dialogue on how to strengthen this supra-national level of industrial relations
Institutions or resources and capabilities? Explaining engagement in European sectoral social dialogue
We analyse social partner engagement in European sectoral social dialogue, testing two prominent theories to disentangle sector and country dynamics: institutional and resources and capabilities theories. While institutional theory accounted for certain social partner preferences, resources and capability theory proved stronger in predicting participation and provided insight into regulatory preferences. We conclude that resources and capability theory better explains our case, associating it with weaknesses of transnational governance. Specifically, limited incentives for participation mean that social partners with fewer resources forego participation, entailing pre-eminence of social partners with greater resources and hindering outcomes reflecting national institutional influences
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