Climatic specialisation: an explanation for the range size and distribution of bryophytes on a tropical island elevational gradient

Are species physiologically specialised to the specific climatic conditions in their habitats and can this explain their distributions? This thesis addresses this question using a very specific system: bryophytes on the elevational gradient of Piton des Neiges, Réunion Island. Bryophytes are expected to be specialised to fairly narrow conditions of drought, temperature and insolation, which restrict their geographic range. However, little is known about the mechanisms that connect bryophytes with climatic factors. In this thesis I test the idea of ecophysiological specialisation using reciprocal transplant experiments, along with direct laboratory measurements of species' responses to desiccation and temperature. In these experiments I use species restricted to low, mid or high elevation, as well as widespread species found along most of the gradient. The transplant experiment revealed a trend of upslope survival of restricted species, with species from all sites performing best at their elevation of origin and the site above, and badly at lower elevations. Despite macroclimate being found as an important factor shaping bryophyte range size and distribution, the effect of microhabitat could not be ignored. This was especially true for the widespread species, which showed a strong effect of microhabitat placement in the transplant experiment. Desiccation tolerance was found to increase with elevation in range-restricted species, but widespread species showed little difference in their sensitivity to desiccation, regardless of elevation of origin. Range-restricted species from low elevation were more sensitive to low temperatures and had higher optimum temperatures for photosynthesis than mid- and high-elevation species. Widespread species had narrower ranges of temperature tolerances than range-restricted species, and did not differ in their response to temperature, regardless of elevation of origin. The results of these experiments corresponded well with the climatic conditions that these species habitually experience – with extremes at the gradient peripheries and intermediate conditions in between. This thesis showed that specialisation to both macro- and microclimatic conditions can be attributed as a main driver of bryophyte range size and distribution on the elevational gradient of Piton des Neiges, Réunion Island. This research adds to the body of knowledge on the physiological responses of tropical bryophytes, which is important for species' distribution modelling. Furthermore, it provides insight into the factors that shape bryophyte distribution, critical for biodiversity management under climate change scenarios

Interpretive communities of resistance: Emerging counterpublics of immigration alarmism on social media

Debates over immigration have become a defining political cleavage closely related to moral values, perceptions of threat, and the rise of online anti-immigration networks and agitation. Based on in-depth interviews with immigration alarmists, this article discusses how the participants’ anti-immigration position is sanctioned in their everyday social networks and how they find alternative networks online for information, community, and support. This online community takes the form of an emerging counterpublic, characterized by active curation and different levels of participation aimed at optimizing the trade-offs between gaining visibility (moderation and mobilization) and creating an alternative moral community (a “safe space” for peers). Combining notions of interpretative communities of resistance with the theory of counterpublics, the study provides insight into the internal life and values of emerging anti-immigration online communities.Interpretive communities of resistance: Emerging counterpublics of immigration alarmism on social mediapublishedVersio

The Boosted DC Algorithm for Clustering with Constraints

This paper aims to investigate the effectiveness of the recently proposed Boosted Difference of Convex functions Algorithm (BDCA) when applied to clustering with constraints and set clustering with constraints problems. This is the first paper to apply BDCA to a problem with nonlinear constraints. We present the mathematical basis for the BDCA and Difference of Convex functions Algorithm (DCA), along with a penalty method based on distance functions. We then develop algorithms for solving these problems and computationally implement them, with publicly available implementations. We compare old examples and provide new experiments to test the algorithms. We find that the BDCA method converges in fewer iterations than the corresponding DCA-based method. In addition, BDCA yields faster CPU running-times in all tested problems

A comparison of three methods of Nitrogen analysis for feedstuffs

(South African J of Animal Science, 2000, 30, Supplement 1: 23

Open innovation in the public sector:A literature review on actors and boundaries

Open innovation (OI) is increasingly being adopted by city administrations and municipalities. However, the extent to which the public sector applies OI is yet unclear. Furthermore, studies in OI in public organizations has primarily focused on citizen inclusion and the barriers and drivers of attracting and engaging citizens and seldom considered other external actors, such as academia and other public organizations. Consequently, this study reviews the literature on OI in public organizations and applies the concept of organizational boundary to interpret the relationships among OI actors in the public sector. The review identifies that the maturity of OI in public organizations are low between all actors and these organizations differ to a great extent in terms of which aspects of organizational boundary are open. However, grand challenges and social innovation are exceptions demonstrating a high level of maturity. Furthermore, the use of intermediaries has the potential of opening all aspect of boundaries and hence achieving a high level of success. Finally, the framework presented in this review is used to suggest future research

Cloud water interception and resilience of tropical montane bryophytes to climate change in cloud forests of La Reunion

Tropical montane cloud forests (TMCFs) are characterized by frequent cloud immersion, host a high diversity of global biodiversity and provide vital ecosystem services to insular populations. Climate change on islands, is expected to both raise the cloud height base as a result of temperature increase and to increase the frequency of extreme events like drought. Bryophytes contribute a significant biomass in these systems yet the role of cloud water and the resilience of bryophytes to drought in island TMCFs is still poorly known. In La Reunion, we implemented a novel method to follow cloud water interception by bryophytes in the TMCF using in situlysimeters. We showed that two abundant TMCF liverworts possess an excellent ability to intercept and store cloud water, and that stored water fluctuated according to climatic conditions. In order to better understand the ecophysiology of TMCF bryophytes, we examined chlorophyll fluorescence, under laboratory conditions, for 16 bryophyte species in response to dehydration and rehydration. This was accompanied by measurements of water retention capacity and relative water content of each species. Highest Water Retention Capacity and Relative Water Content were recorded for Sphagnumsp ( 2174 %: 91,37 %) and Anthocerossp ( 1540 %; 7815 %). Dry down curves showed that species with high water storage capacity are favored by maintaining longer optimal photosynthetic activity. After one week of desiccation, half of the species could recover 50 % of their optimal photosynthetic activity within 24 h of rehydration. Most species, after 7 weeks of desiccation, could not recover their original photosynthetic activity after rehydration. These experiments highlight the presence of various strategies for managing desiccation by TMCF bryophytes at the microhabitat level. Bryophytes inhabiting the TMCF, exhibit a strong strategy in either tolerance or drought avoidance or a combination of both strategies, indicating a better adaptation to drought than expected. However, impact of repetitive drought on the physiology of the TMCF species remains unknown. The multiplicity of responses recorded for TMCF bryophytes regarding their physiology and life forms indicate that climate change will have distinct impacts on species

Contesting the Mainstream:Understanding Alternative News Media and Its Contribution to Diversity

In this introduction to the special issue Contesting the Mainstream: Understanding Alternative News Media, we discuss how and to what extent alternative news media contribute to news diversity. We elaborate on the concept of diversity, the democratic role of media, and the normative implications of alternative media in the wider media sphere. Based on the articles published in this special issue, that offer new and revealing empirical insights into a wide range of alternative media sites and their practices, from Europe, Asia, the Middle East, North America, and Latin America, we argue that it becomes increasingly clear that awareness about normative positions within alternative media research is imperative. This is because an appreciation of the normative purpose of alternative media guides our ability to understand their role in society. The necessity for thinking through such positions is particularly exemplified by the most radical alternative media actors, and how they are debated and studied in different political systems

Open Polar – a global open access portal to research on the polar regions

Poster presentation at the Svalbard Science Conference 2021, Fornebu, 02.11.21 - 03.11.21, arranged by Research Council of Norway. https://www.forskningsradet.no/en/svalbard-science-forum/ssf-tools-and-funding-schemes/svalbard-science-conference/. Research activities and research output, in general, have increased, and keep increasing vastly, and so too is research on the polar regions including Svalbard in the Arctic. Major commercial publishers have built subscription-based services which present research literature for a fee. As Open Science and open access to literature and data is gaining momentum, there is a distinct need for powerful discovery tools that can harvest and present research literature and datasets in open access form - free of charge. Moreover, sharing of underlying data in open access form is becoming the new norm. So, to integrate research papers and datasets in the same search, helps speed up the discovery processes as well as fostering the transparency of research, and minimize duplication of fieldwork and experiments. Open Polar (https://openpolar.no/) is developed by UiT The Arctic University of Norway, and is a free to use discovery tool for open access publications and research data specifically targeting research output on the polar regions, across all subject areas, and irrespective of where the research originates. Through a carefully designed algorithm, Open Polar is extracting metadata (including URL to the landing page of the full text) from more than 4600 sources worldwide and making these accessible through a user-friendly search service - including an option to search via geolocations on a map, and with systematic search features. The algorithm used picks up relevant research located in the most remote content providers and sources. Thus, searching in Open Polar will result in records purely of relevance to the polar regions. In this contribution, we will present the many advantageous features of Open Polar, and show how Open Polar is supporting Open Science and research integrity-enhancing procedures, by enabling search and access to research data as well as research papers