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Proton conducting graft copolymers with tunable length and density of phosphonated side chains for fuel cell membranes

Polysulfones functionalized with highly phosphonated poly(pentafluorostyrene) side chains of different length were synthesized applying controlled polymerization and modification methods. The graft copolymers' thermal properties were evaluated by differential scanning calorimetry and thermal gravimetrical analyses. The proton conductivity of membrane prepared from the graft copolymer with the shor

Dvärgagen återupptäckt i Sverige efter 63 år som utgången.

Cyperus fuscus was thought to be extinct in Sweden until it was rediscovered at Lake Vombsjön, Skåne, after 63 years in 2013. The species also occurred at the lake 2014—2021, but in very variable numbers. The variation depended largely on the water level during late summer. Favourable conditions in form of low levels in late summer have also occurred prior to 2013, though less frequently than in rCyperus fuscus was rediscovered at Lake Vombsjön in Skåne, southernmost Sweden, in 2013. The species occurred there between 1945 and 1950, which was the latest Swedish record except for a casual occurrence in a plant nursery. The comeback was spectacular with 2770 individuals counted along 4.7 km of the shore. In 2013, the water level was exceptionally low for technical reasons, with up to 100 m o

Does inbreeding promote evolutionary reduction of flower size? Experimental evidence from Crepis tectorum (Asteraceae).

• Premise of the study: Small, autogamous flowers have evolved repeatedly in the plant kingdom. While much attention has focused on the mechanisms that promote the shift to autogamy, there is still a paucity of information on the factors that underlie the reduction of flower size so prevalent in selfing lineages. In this study of Crepis tectorum, I examine the role of inbreeding, acting alone or t

Government Effectiveness and Regional Variation in Informal Employment

Abstract in UndeterminedThis article analyses the role of government effectiveness in the determination of informal employment. A theoretical model is developed, in which local governance and worker skill level are assumed to influence the decision of the worker whether to seek employment in the formal or informal sectors. The model is assessed empirically using data from Brazil, where almost half

Factors of importance for maintaining work as perceived by men with arthritis

OBJECTIVE: Employment rates are significantly lower among individuals with arthritis compared to a general population. There is, however, limited research about how men with arthritis perceive their ability to maintain working. The aim of this study was thus to explore their perception of this. PARTICIPANTS: Nine employed men with arthritis were purposively sampled. METHODS: Interviews were perfor

Distortional hardening plasticity model for paperboard

A distortional hardening elasto-plastic model at finite strains suitable for modeling of orthotropic materials is presented. As a prototype material, paperboard is considered. An in-plane model is established. The model developed is motivated from non-proportional loading tests on paperboard where the paperboard is pre-strained in one direction and then loaded in the perpendicular direction. A sof

The anomalous hyperfine structure of Al II

The hyperfine structure of a large number of transitions in Al II cannot be described using A and B hyperfine constants and the hyperfine structure is therefore said to be anomalous. In this paper, we have studied the hyperfine structure of a few transitions in Al II, 3s5s(3)S-3s5p(3)P, 3s4d(3)D-3s5p(3)P and 3s5p(3)P-3s5d(3)D, by combining theory and experiment. It is shown that the anomalous hype

Blood Velocity Estimation Using Ultrasound and Spectral Iterative Adaptive Approaches

This paper proposes two novel iterative data-adaptive spectral estimation techniques for blood velocity estimation using medical ultrasound scanners. The techniques make no assumption on the sampling pattern of the emissions or the depth samples, allowing for duplex mode transmissions where B-mode images are interleaved with the Doppler emissions. Furthermore, the techniques are shown, using both

Propagating Surface Plasmon Induced Photon Emission from Quantum Dots.

We investigate the interaction between propagating surface plasmons in silver nanowires and excitons generated in quantum dots. We show propagating surface plasmons can excite excitons, which results in quantum dot emission. In this process, the energy is directly transferred from the propagating surface plasmons to the excitons without converting to photons. Furthermore, we demonstrate the revers

Fibromodulin and Dystrophin in Atherosclerosis: Novel roles for extracellular matrix in plaque development

Popular Abstract in Swedish Fibromodulin och dystrofin i ateroskleros; en populärvetenskaplig sammanfattning VAD ÄR ATEROSKLEROS? Ateroskleros – det man tidigare kallade för åderförkalkning – är grundorsaken till hjärtinfarkt, stroke och kärlkramp. Ett aterosklerosplack är en förträngning i ett blodkärl, ofta vid en förgrening där blodflödet är turbulent. Placket börjar ofta växa redan i unga år Cardiovascular disease represents nearly half the cases of noncommunicable diseases worldwide and is the leading global cause of death. The main underlying cause is atherosclerosis, and in atherosclerotic plaque progression the structure, composition and integrity of a dynamic extracellular matrix (ECM) is one very important factor. This thesis discusses the importance of the connection between th

Endwall heat transfer and aerodynamic performance of bowed outlet guide vanes (OGVs) with on- and off-design conditions

In this study, numerical simulations are conducted to investigate the effects of bowed outlet guide vanes (OGVs) on endwall heat transfer and aerodynamic performance. Both on- and off-design conditions are studied. For bowed vanes, the bowed angle varies from 10 degrees to 40 degrees and the normalized bowed height ranges from 0.1 to 0.3. Results are included for Nusselt number distributions on th

Use of geoinformatics for inter-basin water transfer assessment

Fresh water availability and demand are unevenly distributed both temporally and geographically. Furthermore, the availability of fresh water has remained more or less constant, while the demand for clean water is steadily increasing. With demand surpassing supply, an integrated water resource management approach is required to ensure even distribution of potable water to all levels of society whi

Phenotypic and functional analysis of the mesenchymal stromal cell compartment in the thymus

T cells are key cellular components of the adaptive immune system that play a critical role in our defense against pathogens and cancer but also contribute to pathology in the setting of chronic inflammation and autoimmunity. The thymus constitutes the body's major T cell production site, where bone marrow-derived progenitors migrate in a co-ordinated fashion through anatomically distinct cortical

Governance approaches that can be used to implement sustainability criteria

Implementation of sustainability criteria, both in legal frameworks and voluntary sustainability standards, is an urgent and important issue. In the article, three less state-centric governance approaches and their capacity to be used to implement sustainability criteria have been investigated. The chosen approaches are good governance, multi-level governance and selfgovernance. Their potential st

Genetic variants on chromosome 5p12 are associated with risk of breast cancer in African American women: the Black Women's Health Study

Two single nucleotide polymorphisms (SNPs), rs4415084, and rs10941679 on chromosome 5p12 were associated with risk of breast cancer in a recent genome-wide association study (GWAS) of women of European ancestry. Both SNPs are located in a large high-LD region and the causal variant(s) are still unknown. We conducted a nested case-control study in a cohort of African American women to replicate and

Stroke genetics: a review and update.

Stroke genetics includes several topics of clinical interest, including (1) molecular genetic variations affecting risk of monogenic stroke syndromes; (2) molecular genetic variations affecting risk of common stroke syndromes, sometimes with specific effects on risk of specific main types of stroke or subtypes of ischemic and hemorrhagic stroke; (3) genetics of conditions associated with stroke ri