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Evaluation of Ulva lactuca hydrolysates as a feedstock for clostridial fermentations to produce 1,2-propanediol
(2026-03-26) Ingvadóttir, Eva María; Scully, Sean Michael; Örlygsson, Jóhann; Faculty of Natural Resource Sciences
Macroalgae are an abundant and underutilized renewable feedstock that can be exploited for the production of various low- and high-value biomolecules. The study herein describes a mild acid and base process to hydrolyze the green macroalgae Ulva lactuca into simpler, fermentable carbohydrates, with an emphasis on rhamnose. Hydrolysis experiments involving up to 5% v/v sulfuric acid and 5% w/v sodium hydroxide at temperatures between 25 and 100 °C demonstrated that the highest recovery of fermentable carbohydrates was generally obtained using 2.5% v/v sulfuric acid at 75 °C. Two Clostridium species ( Clostridium strain AK1 isolated from SW Iceland, and Clostridium beijerinckii strain DSM 791) were used to ferment L-rhamnose to 1,2-propanediol, both as a single substrate and as part of macroalgal hydrolysates. Additionally, the impact of culture conditions (pH and initial substrate concentration) on rhamnose fermentation was investigated in batch culture for both strains. Generally, pH did not influence the production of 1,2-propanediol and both strains partially degraded rhamnose at very low (10 mM) initial substrate concentrations. A kinetic investigation of rhamnose utilization using strain AK1 showed that the pentose is degraded much slower as compared with glucose with 1,2-propanediol production lagging and reaching a maximum concentration of 7.7 mM. When Clostridium strain AK1 was cultivated on U. lactuca hydrolysates and non-pretreated U. lactuca , the maximum yields were 7.9 mM 1,2-propanediol. This is the first report of the production of 1,2-propanediol from macroalgal biomass using a moderately thermophilic Clostridia.
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Réttur til réttargæslumanns : Þjóna skilyrðin vilja löggjafans?
(2024-03) Antonsdóttir, Júlí Ósk; Lagadeild
Victims' rights are in the spotlight these days. This article deals with victims of crime and their right to have a designated or appointed legal aid to protect their interests during the handling of a case concerning a crime against them. It will discuss the conditions set by law for the nomination and appointment of a legal aid and how the courts have interpreted the conditions in case law and why it is necessary to change the conditions to better ensure the interests of victims of crime and especially victims of domestic violence.
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Decarbonising Road Freight Transport in Iceland : A Feasibility Assessment Under Harsh Climate Conditions in Remote Regions
(2025-02) Villar, Albert Alonso; Stefánsson, Hlynur; Ásgeirsson, Eyjólfur Ingi; Kristjánsson, Ragnar; Department of Engineering
Background: The decarbonisation of road freight transport is a multifaceted challenge, which involves technical, economic, social, and infrastructural considerations. Heavy-Duty Vehicles (HDVs), responsible for 40% of the emission in the transport sector, operate across diverse and demanding applications and are heavily reliant on fossil diesel, making their decarbonisation complex. While existing literature has largely focused on addressing a specific aspect of the HDV transition, such as greenhouse gas emissions (GHG) analysis, technical assessments of a limited range of powertrains and configurations, or isolated evaluations of infrastructure requirements, these studies often overlook the well-to-wheel nature of the decarbonisation challenge. In Iceland, the complexity of this challenge is further expanded by the harsh climate conditions, sparse population, and ageing infrastructure. While Iceland’s abundant renewable energy presents an opportunity to transition away from fossil fuels in the freight sector, the transition demands a comprehensive understanding of the technical feasibility and infrastructure requirements. Aim: This thesis begins with a comprehensive evaluation of alternative fuel powertrains to identify the most favourable solution to decarbonise road freight transport in Iceland. Based on this initial assessment, the thesis focuses on Battery-Electric Trucks (BETs) as the most promising solution to achieve the decarbonisation goals, conducting a detailed assessment of the feasibility and implications of HDV electrification in Iceland. This research addresses the unique challenges posed by Iceland’s Arctic-like climate and remoteness, seeking to bridge the existing gaps by integrating multiple dimensions of the transition using real-life data, including detailed vehicle energy performance assessments under adverse conditions, optimal charging network design, and impact of charging loads on the power grid. Overall, the main goal of this thesis is to answer the question “Are BETs a feasible option to decarbonise the road freight transport sector in Iceland?”. Method: To achieve our goal, this thesis first evaluates the technical, environmental, and economic feasibility of multiple powertrain options in Iceland, including BET, hydrogen fuel cell (FCV), and other alternative fuels. This analysis is carried out using AFLEET and GREET databases to assess the HDV life cycle emissions and total cost of ownership (TCO), as well as considering factors like energy security and local fuel production capacity. Subsequent studies focus specifically on battery-electric powertrains, assessing their performance using detailed vehicle energy consumption models (FASTSim) to account for adverse climate and freight conditions. Additionally, a novel methodology for planning fast-charging infrastructure is proposed, which incorporates a non-linear charging optimisation framework to determine the magnitude of charging loads from battery-electric trucks and locate power demand points from fast-charging stations along Iceland’s main freight routes. Finally, PyPSA is used to conduct power flow simulations to evaluate the effects of charging loads from battery-electric trucks on the national grid and identify potential bottlenecks in the infrastructure. This integrative methodology provides a comprehensive understanding of the technical feasibility, infrastructure requirements, and systemic impacts of freight transport electrification. Results: The findings indicate that battery-electric trucks offer significant environmental and economic advantages, despite the limitations of current battery technology. Hydrogen and compressed natural gas are promising alternatives for regional trucks but are constrained by high life cycle costs and insufficient feedstock availability. The battery-electric truck performance analysis reveals a range reduction of 41–47% under challenging conditions, emphasising the necessity of on-route charging for full fleet electrification. The proposed charging infrastructure planning methodology highlights that larger batteries and higher charging rates can minimise routing delays, while power flow simulations indicate that the additional charging loads can cause localised grid bottlenecks, particularly in remote regions like the Westfjords. Conclusion: Overall, the outcomes of this thesis emphasise the feasibility of electrifying road freight transport in Iceland, although strategic planning will be required to mitigate grid constraints, especially in the Westfjords and other vulnerable areas. By integrating technical, economic, and environmental assessments, this thesis provides a holistic framework for guiding road freight electrification in Iceland and similar regions. The findings contribute to advancing sustainable freight transport while offering a scalable approach for other similar challenging contexts globally.
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Áföll, vald, samskipti: Upplifun prédikarans á átakatímum í ljósi prédikunarfræði.
(University of Iceland, School of Humanities, Faculty of Theology and Religious Studies, 2026-03-12) Jörgensson Berndsen, Fritz Már; Dr. Sigríður Guðmarsdóttir og Dr. Pétur Pétursson; Guðfræði- og trúarbragðafræðideild (HÍ); Hugvísindasvið (HÍ)
Prédikunarfræði (e. homiletics) snerist löngum um undirbúning prédikunar, flutning hennar og miðlun. Á síðari árum hafa prédikunarfræðingar beint sjónum sínum að reynslu prédikarans sjálfs. Í ritgerðinni sem hér er sett fram er fengist við þau áhrif sem sjónarhóll og upplifanir prédikara hafa á prédikun. Samfélagslegar aðstæður áheyrenda eru einnig lykilþáttur í prédikunarfræðilegri umfjöllun ritgerðarinnar þar sem færð eru rök fyrir því að prédikunarfræðingar hafi almennt ekki gefið nægjanlegan gaum að þeim samfélagslegu áföllum er prédikarar og áheyrendur hafa upplifað. Tímabilið frá lokum 20. aldar til upphafs 21. aldar voru átakatímar fyrir þjóðkirkjuna sem þurfti að fást við mál er ollu henni og þjónum hennar vandræðum. Málin sem valin voru eru ferns konar og byggja sögulega greiningu ritgerðarinnar. Ein hjúskaparlög og kirkjuleg hjónavígsla hinsegin fólks olli deilum í samfélaginu og innan þjóðkirkjunnar. Næst kemur hið svokallaða biskupsmál er hófst árið 1996 þegar tvær konur ásökuðu þáverandi biskup Ólaf Skúlason um kynferðisbrot. Þá má nefna Kristnitökuhátíð á Þingvöllum sem var gagnrýnd vegna náins samstarfs þjóðkirkjunnar við Alþingi og valdamenn í stjórnmálum. Að lokum er fjallað um efnahagshrunið á Íslandi árið 2008 sem var einstakur viðburður sem leiddi af sér samfélagslegt áfall. Áskoranir átakatímabilsins fyrir, í og eftir hrun höfðu áhrif á hina evangelísk-lúthersku þjóðkirkju á Íslandi sem glímdi á þessu tímabili við ýmsar áskoranir af félagslegum toga. Höfundur rannsakar áhrif prédikunar á þessu tímabili og greinir áhrif þessa átakatímabils á prédikara og prédikun þeirra. Í ljósi prédikunarfræða má álykta að atburðir sem þessir geti haft áhrif á hvort tveggja, prédikara og áheyrendur þeirra. Átakatímabil vísar hér til samfélagslegra og stofnanatengdra umbreytinga sem höfðu áhrif á íslenskt samfélag, þjóðkirkju og prédikun presta á tímabilinu 1995-2015. Rannsóknarspurning ritgerðarinnar er: Hver er upplifun presta á Íslandi af því að prédika á átakatímum í aðstæðum hruns og áfalla? Ein af hinum stóru áskorunum ritgerðarinnar lýtur að áhrifum ólíkra tegunda valds og mögulegum áhrifum valdastöðu og misbeitingar valds á prédikun. Þessir þættir verða rannsakaðir út frá kenningum um áfallatengda prédikun. Aðrar kenningar sem ritgerðin byggir á lúta að tungutaki og samskiptum í prédikun. Í samtímanum verða samskipti prédikara við áheyrendur stöðugt flóknari, rétt eins og aðferðir til miðlunar á prédikun. Umræða í prédikunarfræði tengd hugmyndum úr síðnýlenduhyggju (e. postcolonialism) um áföll og vald hefur haft þau áhrif að nýjar rannsóknir á birtingarmyndum þessara þátta hafa fengið aukið rými. Ritgerðin byggir á eigindlegri viðtalsrannsókn þar sem tekin voru viðtöl við átta starfandi presta innan þjóðkirkjunnar um reynslu þeirra og upplifanir í samfélagslegu áfalli efnahagshrunsins. Viðtölin eru síðan greind og túlkuð út frá áðurnefndum kenningum. Viðmælendur rannsóknarinnar, rétt eins og áheyrendur þeirra, þurftu að fást við afleiðingar áfalla í eigin lífi, starfi og prédikun. Rætt er um mál sem tengjast lykilhugtökum ritgerðarinnar og prédikun tengda þeim. Þar ber á góma málefni á borð við traust, sjálfsmat presta, texta, tungutak, túlkun, samfélagsleg álitamál og áfallaaðstæður. Niðurstöður ritgerðarinnar benda til þess að átakatíminn ásamt samfélagslegu áfalli hruntímans hafi haft mikil áhrif á prédikara og áheyrendur þeirra. Í niðurstöðunum er að finna samsvörun við aðrar rannsóknir á reynslu prédikara af samfélagslegum áföllum. Nýsköpun þessarar ritgerðar felst í því að rannsaka reynslu íslenskra presta á umbrotatímum í sögu íslensks samfélags og þjóðkirkju.
Verk
Manifestations of inequality among adolescents in Bissau, Guinea-Bissau
(University of Iceland, School of Social Sciences, Faculty of Sociology, Anthropology and Folkloristics, 2026) N´dure Baboudóttir, Fatou; Geir Gunnlaugsson; Félagsfræði-, mannfræði- og þjóðfræðideild (HÍ); Faculty of Sociology, Anthropology and Folkloristics (UI); Félagsvísindasvið (HÍ); School of Social Sciences (UI)
Introduction. In low-income countries, particularly in sub-Saharan Africa, adolescents (aged 10–19 years) are a rapidly growing demographic; however, their needs beyond sexual and reproductive health remain under-researched. This article-based thesis explores, through five peer-reviewed publications, the manifestations of inequality among adolescents in Bissau, the capital of Guinea-Bissau, a low-income and fragile state in West Africa. Guided by the theoretical framework of social determinants of health and childhood and youth studies, it examines how structural conditions impact adolescents' life experiences and how they navigate the challenges they face. Aims. The overall aim of the research is to describe, analyse, and synthesise the manifestations of inequality in the lives of adolescents in Bissau. The specific aims are to explore (1) the social determinants of adolescents’ unequal access to education and use of digital technologies (Papers I–II and IV); (2) adolescents’ understanding of inequality in their daily lives and during global health crises (Papers III–V); and (3) adolescents’ responses to challenges in their everyday lives and during global health crises (Papers III– V). Methodology. Data collection is based on a multi-phase, mixed-methods approach in which quantitative methodology informs the qualitative component. The quantitative aspect consists of a Planet Youth survey questionnaire conducted among 2,039 school-attending adolescents (aged 14–19) in 12 public and four private schools in Bissau, analysing the determinants of educational and digital access. The results informed the qualitative component of the research, which included semi-structured interviews, focus group sessions, and a participatory photovoice project to explore adolescents' daily experiences across different socioeconomic backgrounds and during the COVID-19 pandemic. Results. Findings reveal deep-seated inequalities. Access to education is starkly divided, with parental education and family income being the strongest determinants for enrolment in private schools, which offer more educational stability compared to resource-poor public schools, plagued by strikes and teacher absenteeism. Furthermore, access to computers and the internet is limited, disadvantaging girls and public-school students. The COVID-19 pandemic exposed the global digital divide; school closures led to a universal loss of education in both public and private schools, with no remote learning provided or other support. Some adolescents reported hunger and a lack of food security, underscoring local inequality. Through the photovoice project, they insightfully outlined structural inequalities in their daily lives. Despite these barriers, the adolescents demonstrated remarkable determination, empathy, and strong aspirations for the future, proposing practical solutions to the challenges they face. Conclusions. Adolescents in Bissau confront systemic and interconnected inequalities in their daily lives. Their experiences necessitate integrated, equity-focused interventions targeting the socioeconomic determinants of health. By centring adolescents’ perspectives, the findings underscore the necessity of a child rights-based approach that institutionalises youth participation in policy and decision-making. The results highlight the importance of recognising adolescents as active agents in achieving sustainable development and a more equitable future for the next generation in Guinea-Bissau, with potential implications elsewhere.

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