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Leadership for Social Justice for Immigrant Students and Their Families in Icelandic Schools
(University of Iceland, School of Education, Faculty of Education and Diversity, 2026) Svavarsson, Helgi Þorbjörn; Börkur Hansen; Faculty of Education and Diversity (UI); Deild menntunar og margbreytileika (HÍ); School of Education (UI); Menntavísindasvið (HÍ)
In recent decades, Iceland has undergone significant demographic changes because of increased immigration. The population of Iceland has transitioned from being primarily homogeneous to being multicultural, characterized by diverse languages, customs, and cultural norms. These developments have had a broad impact across all sectors of society, particularly the school system, which has had to adapt to this new reality. Previous research has indicated that despite positive intentions and changes in legislation and curricula, students from immigrant backgrounds do not enjoy the same opportunities as their native peers. They experience higher dropout rates and disadvantages in academic achievement and access to learning opportunities. This doctoral project focuses on leadership in preschools, compulsory schools, and upper-secondary schools with a high proportion of immigrant students that have demonstrated success in advancing social justice. The study aims to highlight the experiences and perspectives of school leaders to identify leadership practices that contribute to the success of these schools. The guiding research question is: What leadership practices can be identified as influential in advancing and sustaining social justice for immigrant students and their families within school communities? Building on critical realism and critical leadership theory, the study employs a multiple case study approach. Data were collected through semi structured interviews with school principals and key staff working with immigrant students in nine schools, three at each educational level. Additional interviews were conducted with preschool parents and compulsory school teachers. The research builds on four publications: three articles and one book chapter. Together, the four publications explore how school leaders in Iceland navigate the interplay between societal structures and leadership agency to promote and sustain social justice for immigrant students. Data were analyzed using framework analysis with different theoretical frameworks applied according to the content of each article, and retroduction analysis to identify underlying forces that promote or hinder social justice. The findings from the four publications are synthesized and examined through the lens of Woods’s (2016) trialectic framework, which is grounded in Archer’s (2003) theory of the interplay between cultural, social, and institutional structures and agency and how these elements influence and shape one another. Woods further distinguished agency into two dimensions: person (individual characteristics) and practice (actions), which together create conditions and possibilities for the leader’s capacity to influence the structures. The study highlights the tension between structural conditions, leadership characteristics, and leadership practices and how they interact to either promote or hinder social justice. The findings indicate that democratic values, ideals of equality, and high levels of societal trust support inclusive leadership, whereas stereotypes about the “normal” student, monolingualism, policy ambiguity, lack of funding, marginalized multicultural teacher education, and negative views of immigrant students function as structural barriers to social justice leadership. The school leaders in this study responded to these barriers by drawing on four core strengths: a strong commitment to social justice, high expectations for all students, an activist mindset, and a pragmatic approach to constraints. Consequently, they worked toward a shared vision by building trust, enhancing staff knowledge and competence in multicultural matters, and creating inclusive learning environments. They employed strategic planning and distributed leadership to engage the school community and address inequities by implementing changes in work practices that reflect student diversity, thereby promoting greater social justice. However, in many cases, this leadership appeared to be highly context-dependent and reliant on individual actors. Moreover, there was a notable lack of formal institutionalization of these practices within the schools’ policies and culture, reducing the likelihood that social justice efforts would be sustained over time. The value of this study lies in its overview of the relationship between societal structures and the promotion of social justice in schools. It highlights the challenges these structures present for school leaders in their efforts to enhance the social and academic positions of immigrant students. This study is part of the Nordic research project Learning Spaces for Inclusion and Social Justice (2013–2015) and is based on empirical data collected during that time. Although the data are not recent, they offer valuable insight into the interaction between structures and agency and into leadership practices within this context, emphasizing the need for further research. Moreover, the findings have practical implications for leadership development and education policy in multicultural contexts.
Verk
Valorization of pulp and viscera from hybrid sorubim and pacu by production of protein concentrate using alkaline solubilization
(2025-03) Azambuja, Suéllen Patrícia Held; Nascimento, Kauyse Matos; Cortez-Vega, William Renzo; Cavenaghi-Altemio, Angela Dulce; Gelinski, Jane Mary Lafayette Neves; Fonseca, Gustavo Graciano; Faculty of Natural Resource Sciences
Fish protein concentration (FPC) by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials. The aim of this work was to evaluate the influence of different processes (decanting/sieving or centrifugation), reagents (sodium bicarbonate or sodium hydroxide) and washing cycles (1–4) on the quality of protein concentrates obtained from mechanically separated meat (MSM) and viscera of hybrid sorubim (Pseudoplatystoma reticulatum × P. corruscans) and pacu (Piaractus mesopotamicus) fishes. The protein concentrate was obtained by washing the viscera or MSM during up to four cycles (4:1 solution:meat ratio). In each cycle, the liquid waste and fat were removed by decanting/sieving or centrifugation. Moisture, crude protein, crude fat and crude ash contents were determined after each washing cycle. The moisture and protein contents increased immediately after the first washing up to 77.88% (dry basis). The lipid content decreased with the cycles down to 2.99% (dry basis). Higher FPC yield was obtained for MSM during the centrifugation process compared to the decantation/sieving process. Two weight yields above 100% were found in procedures with NaHCO3 and MSM of hybrid sorubim and pacu, probably due to the larger capacity of gel formation during protein concentration. Differences related to the fish species were more evident than the processes and utilized reagents.
Verk
Development and characterization of fish nuggets obtained from mechanically separated meat of spotted sorubim
(2026-01-22) Cavenaghi-Altemio, Angela Dulce; Fonseca, Gustavo Graciano; Faculty of Natural Resource Sciences
The fish industry has recently sought to diversify its product offerings to meet high consumer demand beyond just fresh fish. The use of mechanically separated fish meat (MSM) enables the production of various products, including breaded items. This study aimed to develop fish nuggets using MSM from spotted sorubim (Pseudoplatystoma corruscans) as the primary raw material, utilizing various formulations, and to evaluate the pH, shear force, microbiological safety, and sensory attributes of the developed products . The varying ingredients (4%) were bamboo fibre (F1 ), collagen fibre (F2 ), and textured soy protein (F3 ). The average pH of 6.5 showed no statistical difference between formulations (p > 0 .05), indicating that the varying ingredients did not affect this parameter. However, shear force varied significantly (p < 0.05), with the highest value of 8 .82 N observed for F3 . Sensory analysis revealed no significant differences (p > 0.05) between formulations for most attributes, except for taste, where F1 scored higher than F2 and F3 . The acceptance index was above 80% for all formulations . F1 showed the highest “certainly would purchase” response at 26.7%. Both F1 and F3 had a combined acceptance rate of 60% for “certainly and probably would purchase”, while F2 had a 50% acceptance rate. The results suggest that taste plays a crucial role in the sensory acceptance of the nuggets, with bamboo fibre positively enhancing flavour.
Verk
Nitroxide- and trityl-based polarizing agents for MAS-DNP: Synthesis, mechanistic insights, and applications
(University of Iceland, School of Engineering and Natural Sciences, Faculty of Physical Sciences, 2026-09-14) Chatterjee, Satyaki; Snorri Þór Sigurðsson; Faculty of Physical Sciences (UI); Raunvísindadeild (HÍ); School of Engineering and Natural Sciences (UI); Verkfræði- og náttúruvísindasvið (HÍ)
Dynamic nuclear polarization (DNP) is a powerful technique for enhancing the sensitivity of nuclear magnetic resonance (NMR) spectroscopy, enabling the investigation of complex materials and biological systems that are otherwise difficult to analyze. In magic-angle spinning (MAS) under solid-state NMR, the cross-effect mechanism employs biradical polarizing agents to transfer electron polarization to surrounding nuclei. However, many polarizing agents remain difficult to synthesize, often suffer from limited aqueous solubility, and the factors governing polarization transfer are not entirely understood. This thesis describes the design, synthesis, and mechanistic investigation of nitroxide- and trityl-based polarizing agents for MAS-DNP. A high-yielding and step-efficient molecular scaffold, AsymPol-Ester, was synthesized as a versatile precursor for developing watersoluble AsymPol-derivatives of both ionic and non-ionic character, functionalized with carboxylate, phosphate, and glucosamine groups. These derivatives were obtained up to seven-fold higher overall yields than previous analogues while maintaining comparable DNP performance. Systematic structural modifications of AsymPols including linker geometry, conformational flexibility and deuteration revealed that DNP efficiency is not only influenced by electron-spin interactions but also by electron-electron coupling. For trityl-nitroxide biradicals, adding spirocycles on nitroxide reduced DNP sensitivity, that benefit bis-nitroxides, unexpectedly revealed a distinct polarization transfer mechanism in trityl-nitroxide biradicals. Further, nuclear-nuclear double resonance (NUDOR) experiments demonstrated that polarization transfer in trityl-nitroxide biradicals is strongly influenced by the large difference in electron-relaxation rates between the two radicals, in contrast to bisnitroxides where electron-electron coupling governs polarization transfer. In addition, tritylnitroxide derivative, TritylTEMPO-X, with six-fold higher aqueous solubility than PyrroTriPol, was synthesized. Finally, application-specific nitroxide radicals were developed for site-directed spin-labeling of biomolecules for local DNP enhancement, and mono-radicals for incorporation into mesoporous organosilica materials.
Verk
How different life-history strategies respond to changing environments : A multi-decadal study of groundfish communities
(2025-12) Sólmundsson, Jón; Sigurðsson, Ólafur; Jónsdóttir, Ingibjörg G.; Jónsson, Steingrímur; Faculty of Natural Resource Sciences
In recent decades, climate variability has led to significant shifts in the distribution and prevalence of various fish species in the North Atlantic. These changes are well documented for several groundfish species within the zoogeographical transition waters surrounding Iceland, coinciding with variations in seawater temperature. This study analyses groundfish assemblage structure through the frameworks of life-history theory and biogeography. Utilizing annual bottom trawl survey data from 1987 to 2024, groundfish species in the continental shelf waters around Iceland were categorized into three primary life-history strategies: periodic, opportunistic, and equilibrium, based on their life-history traits. Over the study period, these strategies demonstrated distinct responses to environmental changes, influenced by the biogeography of the species. Increased water temperatures were accompanied by an influx of Atlantic and Boreal species, while species richness for Arctic fish remained similar or decreased. Boreal periodic species emerged as the most prominent in Icelandic waters, maintaining long-term stability in abundance and distribution. However, environmental conditions in recent decades have favoured southerly warmer-water (Atlantic) species across life-history strategies, while most Arctic species have experienced declining abundance trends. Opportunistic strategists exhibited the most pronounced temporal changes during the warming period.

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