675 research outputs found

    Evaluation of denoising strategies to address motion-correlated artifacts in resting-state functional magnetic resonance imaging data from the human connectome roject

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    Like all resting-state functional connectivity data, the data from the Human Connectome Project (HCP) are adversely affected by structured noise artifacts arising from head motion and physiological processes. Functional connectivity estimates (Pearson's correlation coefficients) were inflated for high-motion time points and for high-motion participants. This inflation occurred across the brain, suggesting the presence of globally distributed artifacts. The degree of inflation was further increased for connections between nearby regions compared with distant regions, suggesting the presence of distance-dependent spatially specific artifacts. We evaluated several denoising methods: censoring high-motion time points, motion regression, the FMRIB independent component analysis-based X-noiseifier (FIX), and mean grayordinate time series regression (MGTR; as a proxy for global signal regression). The results suggest that FIX denoising reduced both types of artifacts, but left substantial global artifacts behind. MGTR significantly reduced global artifacts, but left substantial spatially specific artifacts behind. Censoring high-motion time points resulted in a small reduction of distance-dependent and global artifacts, eliminating neither type. All denoising strategies left differences between high- and low-motion participants, but only MGTR substantially reduced those differences. Ultimately, functional connectivity estimates from HCP data showed spatially specific and globally distributed artifacts, and the most effective approach to address both types of motion-correlated artifacts was a combination of FIX and MGTR

    Movements and habitat use of native and invasive piscivorous fishes in a temperate and channelized lowland river

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    Lowland temperate rivers provide important habitats for piscivorous fishes, but with their year-round spatial and temporal habitat use is often poorly understood, including their use of off-channel habitats. Here, the movements and habitat use of the piscivorous native Northern pike Esox lucius and invasive pikeperch Sander lucioperca were investigated using acoustic telemetry in the highly regulated (through impoundment) lower River Severn, Western England over a 12-month period, where off-channel habitat availability was limited to a single boat marina. The movements of both species varied with season and temperature, with both species moving greater distances in spring. Increasing water temperatures up to 15 °C resulted in a higher frequency of movements of both species, but movements then decreased at temperatures higher than this. Northern pike detections in the river increased in periods of lower river discharge and warmer temperatures, with the off-channel refuge providing an important habitat all year round (78% of detections occurred there). While 63% of pikeperch detections also occurred in the marina, 89% of these detections occurred between December and April. These results thus emphasise the importance of this limited off-channel habitat as potential spawning locations for invasive pikeperch and foraging areas for native Northern pike

    Complete genome sequence of Meiothermus silvanus type strain (VI-R2).

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    Meiothermus silvanus (Tenreiro et al. 1995) Nobre et al. 1996 belongs to a thermophilic genus whose members share relatively low degrees of 16S rRNA gene sequence similarity. Meiothermus constitutes an evolutionary lineage separate from members of the genus Thermus, from which they can generally be distinguished by their slightly lower temperature optima. M. silvanus is of special interest as it causes colored biofilms in the paper making industry and may thus be of economic importance as a biofouler. This is the second completed genome sequence of a member of the genus Meiothermus and only the third genome sequence to be published from a member of the family Thermaceae. The 3,721,669 bp long genome with its 3,667 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project

    Complete genome sequence of Planctomyces limnophilus type strain (Mü 290).

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    Planctomyces limnophilus Hirsch and Müller 1986 belongs to the order Planctomycetales, which differs from other bacterial taxa by several distinctive features such as internal cell compartmentalization, multiplication by forming buds directly from the spherical, ovoid or pear-shaped mother cell and a cell wall which is stabilized by a proteinaceous layer rather than a peptidoglycan layer. Besides Pirellula staleyi, this is the second completed genome sequence of the family Planctomycetaceae. P. limnophilus is of interest because it differs from Pirellula by the presence of a stalk and its structure of fibril bundles, its cell shape and size, the formation of multicellular rosettes, low salt tolerance and red pigmented colonies. The 5,460,085 bp long genome with its 4,304 protein-coding and 66 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project
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