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Artikel i Nationalencyklopedin

Solid oxide fuel cells (SOFCs) produce electricity with high electrical efficiency and fuel flexibility without pollution, for example, CO2, NOx, SOx, and particles. Still, numerous issues hindered the large-scale commercialization of fuel cell at a large scale, such as fuel storage, mechanical failure, catalytic degradation, electrode poisoning from fuel and air, for example, lifetime in relation

Efficient and robust control strategies can greatly contribute to the reliability of fuel cell systems, and a stable output voltage is a key criterion for evaluating a fuel cell system's reliability as a power source. In this study, a polymer electrolyte fuel cell (PEFC) system model is developed, and its performances under different operating conditions are studied. Then two different novel contr

Applying pre-processing and geometric transformation, for the generalization of building blocks, can lead to spatial conflicts which are mainly resolved by displacement. However, the conflicts may not be resolved, due to the insufficient space for displacement or the existence of other objects that prevent displacement. This article proposes a novel model combining building block displacement and

Across the world, children are forced to leave their homes for far-flung destinations. This global phenomenon has particular impact in Europe, where there are now more child refugees than since World War II. Education plays an important role for children with extraordinary experiences seeking to build meaningful lives in their new context. This article offers a new theoretical approach to underpin

Binas surrande är en viktig komponent för känslan av sommar. Men, förutom många hyllmeter av litteratur om några vanliga arter av honungsbi och humlor, vet vi än idag förvånansvärt lite om många av de tjugofem tusen arter vi kallar bin. Vissa humlor överlever Grönlands minusgrader och hårda vindbyar, medan de i Amazonas snarare älskar skogens höga temperatur och fuktighet. Vissa arter bor i stora The buzzing flight of bees is a popular summer hit. Yet, outside of a few familiar species of honeybees and bumblebees, these fantastic little creatures are still mostly unknown. With about twenty-five thousand species, bees are a very diverse group. They can be found in drastically different habitats. For example, some kinds of bumblebees endure the freezing temperatures and windswept tundra of G

The paper analyzes the need for structural change in the Haitian economy, an economy where the majority make their living in agriculture – a sector characterized by a severe erosion problem. It is argued that tourism does not offer any solution, other than possibly in the long run. The only alternative is export-based industrialization, since Haiti is a small and poor country. Its comparative adva

John Maynard Keynes became world famous with the publication of The Economic Consequences of the Peace in 1919, a harsh critique of the Versailles peace treaty. As a consequence, Keynes was nominated by German professors in economics for the Nobel Peace Prize three years in a row, 1922, 1923 and 1924. Because Keynes was put on the shortlist of candidates, he was evaluated in an advisory report in

Purpose: Predictive biomarkers are needed to aid the individualization of radiotherapy (RT) in breast cancer. Cancer-associated fibroblasts have been implicated in tumor radioresistance and can be identified by platelet-derived growth factor receptor-beta (PDGFRb). This study aims to analyze how PDGFRb expression affects RT benefit in a large randomized RT trial. Methods: PDGFRb was assessed by im

We report here the complete genome sequence and characterization of Yersinia bacteriophage vB_YenP_ϕ80-18. ϕ80-18 was isolated in 1991 using a Y. enterocolitica serotype O:8 strain 8081 as a host from a sewage sample in Turku, Finland, and based on its morphological and genomic features is classified as a podovirus. The genome is 42 kb in size and has 325 bp direct terminal repeats characteristic

The bacteriophage vB_YecM-φR1-37 (φR1-37) is a lytic yersiniophage that can propagate naturally in different Yersinia species carrying the correct lipopolysaccharide receptor. This large-tailed phage has deoxyuridine (dU) instead of thymidine in its DNA. In this study, we determined the genomic sequence of phage φR1-37, mapped parts of the phage transcriptome, characterized the phage particle prot

Despite continued efforts by educators, UN declarations and numerous international agreements, progress is still limited in handling major global challenges such as ecosystem collapse, accelerating climate change, poverty, and inequity. The capacity to collaborate globally on addressing these issues remains weak. This historical review of research on global learning for sustainable development (GL

Young birds in cold environments face a range of age-specific thermal challenges. Studying the thermal biology of young birds throughout ontogeny may further our understanding of how such challenges are met. We investigated how age and environmental parameters influenced surface temperature gradients across various body regions of wandering albatross (Diomedea exulans) chicks on Bird Island, South

Volatiles are of key importance for host-plant recognition in insects. In the pollination system of Lithophragma flowers and Greya moths, moths are highly specialized on Lithophragma, in which they oviposit and thereby pollinate the flowers. Floral volatiles in Lithophragma are highly variable between species and populations, and moths prefer to oviposit into Lithophragma flowers from populations

Control theory is emerging as a source of solutions for many problems in the computing systems domain, and in particular for resource allocation. However, the techniques proposed to date in the literature, do not successfully address the difficulty of devising allocation schemes that are general enough, provide stability guarantees, and can be parametrised and managed by system administrators, or