Search results for "83"
showing 10 items of 1276 documents
Chasing the Origin of Viruses: Capsid-Forming Genes as a Life-Saving Preadaptation within a Community of Early Replicators
2015
Virus capsids mediate the transfer of viral genetic information from one cell to another, thus the origin of the first viruses arguably coincides with the origin of the viral capsid. Capsid genes are evolutionarily ancient and their emergence potentially predated even the origin of first free-living cells. But does the origin of the capsid coincide with the origin of viruses, or is it possible that capsid-like functionalities emerged before the appearance of true viral entities? We set to investigate this question by using a computational simulator comprising primitive replicators and replication parasites within a compartment matrix. We observe that systems with no horizontal gene transfer…
Interactions among bacterial strains and fluke genotypes shape virulence of co-infection.
2015
Most studies of virulence of infection focus on pairwise host–parasite interactions. However, hosts are almost universally co-infected by several parasite strains and/or genotypes of the same or different species. While theory predicts that co-infection favours more virulent parasite genotypes through intensified competition for host resources, knowledge of the effects of genotype by genotype (G × G) interactions between unrelated parasite species on virulence of co-infection is limited. Here, we tested such a relationship by challenging rainbow trout with replicated bacterial strains and fluke genotypes both singly and in all possible pairwise combinations. We found that virulence (host mo…
Et introduksjonskurs til GeoGebra : en designstudie av introduksjonskurset med fokus på å lære å bruke i 1T i videregående skole
2016
Masteroppgave matematikkdidaktikk – Universitetet i Agder 2016 As a teacher, I have observed over the past years a change in focus on the use of tools in the teaching of mathematics. Starting in spring 2015 the use of digital tools by students will be a requirement in the examinations in mathematics at high school level. This means that teachers must be even more aware of how we can best help our students to master the use of such tools while refining their understanding of mathematics. The aim of my study was to find a way to introduce GeoGebra (a mathematical tool with options for dynamic geometry, for plotting functions, and for CAS) to students in grade 11. The introduction should be su…
Conceptualizing Core Aspects on Circular Economy in Cities
2021
Currently, there are many different interpretations in the literature of what a circular economy is and how it functions. As cities are still facing challenges to become fully sustainable, the need for a comprehensive analysis of how the circular economy can be implemented in urban areas is increasing. This article aims at outlining circular cities by their key characteristics and to further explore and provide a framework for fostering circularity at the city level. In order to achieve this goal, we performed a systematic review and analyzed key papers published in the field of circular economy to determine how circular economy practices form circular cities. We discovered that cities play…
Sustainable Infrastructure Projects: Systemic versus Traditional Delivery Models
2021
Sustainability involves multiple environmental, technical, social and economic factors, and such complex analysis requires systemic solutions. Delivery models are key to achieving system benefits and enhancing sustainable development in infrastructure investments. They define the phases of a project, incentive structures, risk sharing and the relationships among the actors in it. They are usually developed early in the project and determine the project dynamics and outcomes. We compared traditional delivery models with systemic ones. We identified and illustrated elements that differ between them through two cases. The contribution is an increased understanding of how systemic infrastructur…
Ecosystem Services at the Archipelago Sea Biosphere Reserve in Finland: A Visitor Perspective
2019
The United Nations Educational, Scientific and Cultural Organization&rsquo
Development of environmental health competencies through compulsory education. A polyhedral approach based on the SDGs
2020
This paper focuses on the competencies in environmental health acquired by students during compulsory education. Questionnaires addressing environmental health problems were completed by 923 students of primary and secondary schools from five different Spanish regions. The results for five challenging situations related to hunger, consumerism, climate change, pollution in the cities and allergies are analysed according to the internal coherence of each sub-competency, i.e., addressing knowledge, skills and attitudes towards these topics. Our results show that problems related to air and water pollution were the most commonly described by the students. Focusing on competency achievement, the…
German Marathon Runners' Opinions on and Willingness to Pay for Environmental Sustainability
2021
Research on sustainability and/in sport and, specifically, on the ecological aspects of participatory sporting events is still very scarce despite the recognition these topics have received by actors like, for instance, the European Commission and the United Nations. Against this backdrop, this paper sheds light on a field that is virtually uncharted in academic research, which is the environmental attitudes and willingness to pay for environmental sustainability of participants in participatory sporting events in Europe. In collaboration with the organizer of the Frankfurt Marathon, a study was conducted with a specific focus on German (speaking) marathon runners. In total 1764 data sets w…
Model to Assess the Quality of Magmatic Rocks for Reliable and Sustainable Constructions
2017
Geomechanical assessment of rocks requires knowledge of phenomena that occur under the influence of internal and external factors at a macroscopic or microscopic scale, when rocks are submitted to different actions. To elucidate the quantitative and qualitative geomechanical behavior of rocks, knowing their geological and physical–mechanical characteristics becomes an imperative. Mineralogical, petrographical and chemical analyses provided an opportunity to identify 15 types of igneous rocks (gabbro, diabases, granites, diorites, rhyolites, andesites, and basalts), divided into plutonic and volcanic rocks. In turn, these have been grouped into acidic, neutral (intermediate) and basic magmat…
Measuring Sustainability with Unweighted TOPSIS: An Application to Sustainable Tourism in Spain
2021
The measurement of sustainability is complex due to its multiple dimensions of different relative importance and different natures. From the perspective of sustainability, three types of tourism can be established: traditional tourism, sustainable tourism, and sustainable impact tourism. In the context of multiple-criteria decision analysis, this paper presents a flexible method for assess and rank decision alternatives based on their sustainability. The proposal does not require the relative importance of each criterion to be precisely assigned beforehand, which reduces the subjectivity of the decision making and yields results that can be of interest for decision makers. To show the diffe…