Search results for "heterogeneity"
showing 10 items of 402 documents
Homozygous familial hypercholesterolaemia: new insights and guidance for clinicians to improve detection and clinical management. A position paper fr…
2014
Item does not contain fulltext AIMS: Homozygous familial hypercholesterolaemia (HoFH) is a rare life-threatening condition characterized by markedly elevated circulating levels of low-density lipoprotein cholesterol (LDL-C) and accelerated, premature atherosclerotic cardiovascular disease (ACVD). Given recent insights into the heterogeneity of genetic defects and clinical phenotype of HoFH, and the availability of new therapeutic options, this Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society (EAS) critically reviewed available data with the aim of providing clinical guidance for the recognition and management of HoFH. METHODS AND RESULTS: Early diagn…
Hydration dependent dynamics in sol-gel encapsulated myoglobin.
2008
In this work we study the effect of hydration on the dynamics of a protein in confined geometry, i.e. encapsulated in a porous silica matrix. Using elastic neutron scattering we investigate the temperature dependence of the mean square displacements of non-exchangeable hydrogen atoms of sol-gel encapsulated met-myoglobin. The study is extended to samples at 0.2, 0.3 and 0.5 g water/g protein fractions and comparison is made with met-myoglobin powders at the same average hydration and with a dry powder sample. Elastic data are analysed using a model of dynamical heterogeneity to take into account deviations of elastic intensity from gaussian behaviour in a large momentum transfer range and r…
Hydrology is reflected in the functioning and community composition of methanotrophs in the littoral wetland of a boreal lake
2010
In lake ecosystems a major proportion of methane (CH4) emissions originate from the littoral zone, which can have a great spatial variability in hydrology, soil quality and vegetation. Hitherto, spatial heterogeneity and the effects it has on functioning and diversity of methanotrophs in littoral wetlands have been poorly understood. A diagnostic microarray based on the particulate methane monooxygenase gene coupled with geostatistics was used to analyse spatial patterns of methanotrophs in the littoral wetland of a eutrophic boreal lake (Lake Kevaton, Eastern Finland). The wetland had a hydrology gradient with a mean water table varying from −8 to −25 cm. The wettest area, comprising the h…
CEFLES2: The remote sensing component to quantify photosynthetic efficiency from the leaf to the region by measuring sun-induced fluorescence in the …
2009
The CEFLES2 campaign during the Carbo Europe Regional Experiment Strategy was designed to provide simultaneous airborne measurements of solar induced fluorescence and CO<sub>2</sub> fluxes. It was combined with extensive ground-based quantification of leaf- and canopy-level processes in support of ESA's Candidate Earth Explorer Mission of the "Fluorescence Explorer" (FLEX). The aim of this campaign was to test if fluorescence signal detected from an airborne platform can be used to improve estimates of plant mediated exchange on the mesoscale. Canopy fluorescence was quantified from four airborne platforms using a combination of novel sensors: (i) the prototype ai…
TNFA promoter polymorphisms and narcolepsy
2003
Narcolepsy is a debilitating sleep disorder that affects up to 0.05% of individuals in Caucasian populations. It is highly associated with the HLA-DR2 group antigen or the HLA-DRB1*1501-DQB1*0602 haplotype, respectively. However, the HLA association by itself cannot sufficiently explain the increased risk to family members, as HLA-DR2 is quite common in the general population and most people harboring the respective genotype do not develop any symptoms of narcolepsy. Situated in the HLA class II region, the TNFA gene is translated into the pro-inflammatory cytokine TNF-alpha. TNFA promoter polymorphisms have been linked to several inflammatory and autoimmune diseases. We analyzed three SNP …
Self-Organization Pathways and Spatial Heterogeneity in Insulin Amyloid Fibril Formation
2009
At high temperature and low pH, the protein hormone insulin is highly prone to form amyloid fibrils, and for this reason it is widely used as a model system to study fibril formation mechanisms. In this work, we focused on insulin aggregation mechanisms occurring in HCl solutions (pH 1.6) at 60 degrees C. By means of in situ Thioflavin T (ThT) staining, the kinetics profiles were characterized as a function of the protein concentration, and two concurrent aggregation pathways were pointed out, being concentration dependent. In correspondence to these pathways, different morphologies of self-assembled protein molecules were detected by atomic force microscopy images also evidencing the prese…
Heterogeneity of traditional and digital media use among older adults : A six-country comparison
2021
The concept of aged heterogeneity has been associated with older adults' ability to adapt to the digital age without a systematic empirical analysis. We analyse retired adults' (aged 62 or more) use of traditional media and their digital equivalents in six countries. First, we ask whether heterogeneity in traditional and digital media use increases with age. Second, we study to what extent gender is related to this heterogeneity, and third, the country differences in the heterogeneity of media use in later life. We analyse the 2018 data (N = 5865) of the ‘Older audiences in the digital media environment’ survey using zero-inflated negative binomial models. The results provide partial suppor…
Carry a big stick, or no stick at all: Punishment and endowment heterogeneity in the trust game
2016
AbstractWe investigate the effect of costly punishment in a trust game with endowment heterogeneity. Our findings indicate that the difference between the investor and the allocator’s initial endowments determines the effect of punishment on trust and trustworthiness. Punishment fosters trust only when the investor is wealthier than the allocator. Otherwise, punishment fails to promote trusting behavior. As for trustworthiness, the effect is just the opposite. The higher the difference between the investor and the allocator’s initial endowments, the less willing allocators are to pay back. We discuss the consistency of our findings with social preference models (like inequality aversion, re…
Heterogeneity at the glass transition: what do we know?
2002
We critically discuss the information that can be obtained from experiments with respect to the existence, the life time, and the length scale of dynamical heterogeneity in glass-forming liquids. The ability to select a dynamically distinguishable subensemble and observe its return to the full equilibrium ensemble is illustrated by examples from multi-dimensional NMR. We also discuss non-resonant hole burning spectroscopy as an example for which two separate time scales are involved.
Spatial correlations of mobility and immobility in a glass-forming Lennard-Jones liquid
1998
Using extensive molecular dynamics simulations of an equilibrium, glass-forming Lennard-Jones mixture, we characterize in detail the local atomic motions. We show that spatial correlations exist among particles undergoing extremely large (``mobile'') or extremely small (``immobile'') displacements over a suitably chosen time interval. The immobile particles form the cores of relatively compact clusters, while the mobile particles move cooperatively and form quasi-one-dimensional, stringlike clusters. The strength and length scale of the correlations between mobile particles are found to grow strongly with decreasing temperature, and the mean cluster size appears to diverge near the mode-cou…