7 research outputs found
Shifts in the source and composition of dissolved organic matter in southwest Greenland lakes along a regional hydro-climatic gradient
Dissolved organic matter (DOM) concentration and quality were examined from Arctic lakes located in three clusters across south-west (SW) Greenland, covering the regional climatic gradient: cool, wet coastal zone; dry inland interior; and cool, dry ice-marginal areas. We hypothesized that differences in mean annual precipitation between sites would result in a reduced hydrological connectivity between lakes and their catchments and that this concentrates degraded DOM. The DOM in the inland lake group was characterized by a lower aromaticity and molecular weight, a low soil-like fluorescence, and carbon stable isotope (δ13C-DOC) values enriched by ~2‰ relative to the coastal group. DOC-specific absorbance (SUVA254) and DOC-specific soil-like fluorescence (SUVFC1) revealed seasonal and climatic gradients across which DOM exhibited a dynamic we term “pulse-process”: Pulses of DOM exported from soils to lakes during snow and ice melt were followed by pulses of autochthonous DOM inputs (possibly from macrophytes), and their subsequent photochemical and microbial processing. These effects regulated the dynamics of DOM in the inland lakes and suggested that if circumpolar lakes currently situated in cool wetter climatic regimes with strong hydrological connectivity have reduced connectivity under a drier future climate, they may evolve toward an end‐point of large stocks of highly degraded DOC, equivalent to the inland lakes in the present study. The regional climatic gradient across SW Greenland and its influence on DOM properties in these lakes provide a model of possible future changes to lake C cycling in high-latitude systems where climatic changes are most pronounced
Genetic variation and exercise-induced muscle damage: implications for athletic performance, injury and ageing.
Prolonged unaccustomed exercise involving muscle lengthening (eccentric) actions can result in ultrastructural muscle disruption, impaired excitation-contraction coupling, inflammation and muscle protein degradation. This process is associated with delayed onset muscle soreness and is referred to as exercise-induced muscle damage. Although a certain amount of muscle damage may be necessary for adaptation to occur, excessive damage or inadequate recovery from exercise-induced muscle damage can increase injury risk, particularly in older individuals, who experience more damage and require longer to recover from muscle damaging exercise than younger adults. Furthermore, it is apparent that inter-individual variation exists in the response to exercise-induced muscle damage, and there is evidence that genetic variability may play a key role. Although this area of research is in its infancy, certain gene variations, or polymorphisms have been associated with exercise-induced muscle damage (i.e. individuals with certain genotypes experience greater muscle damage, and require longer recovery, following strenuous exercise). These polymorphisms include ACTN3 (R577X, rs1815739), TNF (-308 G>A, rs1800629), IL6 (-174 G>C, rs1800795), and IGF2 (ApaI, 17200 G>A, rs680). Knowing how someone is likely to respond to a particular type of exercise could help coaches/practitioners individualise the exercise training of their athletes/patients, thus maximising recovery and adaptation, while reducing overload-associated injury risk. The purpose of this review is to provide a critical analysis of the literature concerning gene polymorphisms associated with exercise-induced muscle damage, both in young and older individuals, and to highlight the potential mechanisms underpinning these associations, thus providing a better understanding of exercise-induced muscle damage
Subbo : Uthyrning av bostäder på nätet med fokus på tillgänglighet
Studies show that a majority of all web applications are not accessible for users with visual impairments and opinions differ on how much extra work is required in order to make a web application accessible for these users. Our purpose is investigating how a web application for housing rentals can be developed in order to be accessible for visually impaired users. We split our development into two iterations where the first one was about developing the web application without focus on accessibility. The goal of the second iteration was to achieve level AA according to the WCAG 2.1 guidelines developed by the World Wide Web Consortium (W3C). AA is the level that all web based information is recommended to achieve. During our accessibility work, text documentation for WCAG 2.1 was used along with three popular tools to identify accessibility issues and judge the accessibility level of the web application. After the second iteration, user tests were conducted with simulated visual impairments. The test persons carried out a number of tasks in our web application, both in a version with and one without our accessibility adjustments. The result of these tests as well as the achieved level of compliance with the WCAG 2.1 guidelines make up the basis of our results. After the accessibility work in the last iteration the web application achieves 48 out of 50 requirements to reach the level AA; unequivocally more than before the accessibility adjustments. Our user tests indicated clear improvements and the test persons experienced a higher degree of accessibility in the adjusted version of the web application. The study resulted in the conclusion that among other things the contrast between background and foreground, correct usage of heading elements, and logical tab order had an impact on how accessible the web applicationed was deemed to be
Design and performance of a dedicated coherent X-ray scanning diffraction instrument at beamline NanoMAX of MAX IV
The diffraction endstation of the NanoMAX beamline is designed to provide high-flux coherent X-ray nano-beams for experiments requiring many degrees of freedom for sample and detector. The endstation is equipped with high-efficiency Kirkpatrick–Baez mirror focusing optics and a two-circle goniometer supporting a positioning and scanning device, designed to carry a compact sample environment. A robot is used as a detector arm. The endstation, in continued development, has been in user operation since summer 2017.</jats:p
Design and performance of a dedicated coherent X-ray scanning diffraction instrument at beamline NanoMAX of MAX IV
The diffraction endstation of the NanoMAX beamline is designed to provide high-flux coherent X-ray nano-beams for experiments requiring many degrees of freedom for sample and detector. The endstation is equipped with high-efficiency Kirkpatrick-Baez mirror focusing optics and a two-circle goniometer supporting a positioning and scanning device, designed to carry a compact sample environment. A robot is used as a detector arm. The endstation, in continued development, has been in user operation since summer 2017