138 research outputs found

    BABEL3&3a : Crustal-Scale Structures of the Precambrian Svecofennian Accretionary Orogen in the Fennoscandian Shield

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    obs typo in the title: The title will be changed to FIRE3&3A: Crustal-Scale Structures of the Precambrian Svecofennian Accretionary Orogen in the Fennoscandian Shield. in the second printed version.Peer reviewe

    Fast computation of the geoelectric field using the method of elementary current systems and planar Earth models

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    International audienceThe method of spherical elementary current systems provides an accurate modelling of the horizontal component of the geomagnetic variation field. The interpolated magnetic field is used as input to calculate the horizontal geoelectric field. We use planar layered (1-D) models of the Earth's conductivity, and assume that the electric field is related to the local magnetic field by the plane wave surface impedance. There are locations in which the conductivity structure can be approximated by a 1-D model, as demonstrated with the measurements of the Baltic Electromagnetic Array Research project. To calculate geomagnetically induced currents (GIC), we need the spatially integrated electric field typically in a length scale of 100km. We show that then the spatial variation of the electric field can be neglected if we use the measured or interpolated magnetic field at the site of interest. In other words, even the simple plane wave model is fairly accurate for GIC purposes. Investigating GIC in the Finnish high-voltage power system and in the natural gas pipeline, we find a good agreement between modelled and measured values, with relative errors less than 30% for large GIC values. Key words. Geomagnetism and paleomagnetism (geomagnetic induction; rapid time variations) ? Ionosphere (electric field and currents

    Absence of polysialylated NCAM is an unfavorable prognostic phenotype for advanced stage neuroblastoma

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    <p>Abstract</p> <p>Background</p> <p>The expression of a neural crest stem cell marker, polysialic acid (polySia), and its main carrier, neural cell adhesion molecule (NCAM), have been detected in some malignant tumors with high metastatic activity and unfavorable prognosis, but the diagnostic and prognostic value of polySia-NCAM in neuroblastoma is unclear.</p> <p>Methods</p> <p>A tumor tissue microarray (TMA) of 36 paraffin-embedded neuroblastoma samples was utilized to detect polySia-NCAM expression with a polySia-binding fluorescent fusion protein, and polySia-NCAM expression was compared with clinical stage, age, <it>MYCN </it>amplification status, histology (INPC), and proliferation index (PI).</p> <p>Results</p> <p>PolySia-NCAM-positive neuroblastoma patients had more often metastases at diagnosis, and polySia-NCAM expression associated with advanced disease (<it>P </it>= 0.047). Most interestingly, absence of polySia-NCAM-expressing tumor cells in TMA samples, however, was a strong unfavorable prognostic factor for overall survival in advanced disease (<it>P </it>= 0.0004), especially when <it>MYCN </it>was not amplified. PolySia-NCAM-expressing bone marrow metastases were easily detected in smears, aspirates and biopsies.</p> <p>Conclusion</p> <p>PolySia-NCAM appears to be a new clinically significant molecular marker in neuroblastoma, hopefully with additional value in neuroblastoma risk stratification.</p

    Infant fecal microbiota composition and attention to emotional faces

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    The gut microbiota has been suggested to influence neurodevelopment in rodents. Preliminary human studies have associated fecal microbiota composition with features of emotional and cognitive development as well as differences in thalamus-amygdala connectivity. Currently, microbiota-gut-brain axis studies cover heterogenous set of infant and child brain developmental phenotypes, while microbiota associations with more fine-grained aspects of brain development remain largely unknown. Here (N = 122, 53% boys), we investigated the associations between infant fecal microbiota composition and infant attention to emotional faces, as bias for faces is strong in infancy and deviations in early processing of emotional facial expressions may influence the trajectories of social-emotional development. The fecal microbiota composition was assessed at 2.5 months of age and analyzed with 16S rRNA gene sequencing. Attention to emotional faces was assessed with an age-appropriate face-distractor paradigm, using neutral, happy, fearful, and scrambled faces and salient distractors, at 8 months of age. We observed an association between a lower abundance of Bifidobacterium and a higher abundance of Clostridium with an increased “fear bias,” that is, attention toward fearful versus happy/neutral faces. This data suggests an association between early microbiota and later fear bias, a well-established infant phenotype of emotionally directed attention. However, the clinical significance or causality of our findings remains to be assessed

    Maternal sensitivity at the age of 8 months associates with local connectivity of the medial prefrontal cortex in children at 5 years of age

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    The quality of mother-child interaction, especially maternal sensitivity in caregiving behavior, plays an important role in a child's later socioemotional development. Numerous studies have indicated associations between poor mother-child interaction and offspring brain structure and function, but more knowledge on how variation in the characteristics of early caregiving is associated with children's brain structure and function is needed. We investigated whether maternal sensitivity at 8 or 30 months is associated with functional connectivity in a child's brain at 5 years of age based on the FinnBrain Birth Cohort Study (17 and 39 mother-child dyads at 8 and 30 months, respectively, with an overlap of 13 dyads). Maternal sensitivity was assessed during a free play interaction using the Emotional Availability Scales at 8 and 30 months of the children's age. Task-free functional magnetic resonance imaging (fMRI) was acquired at the age of 5 years in 7-min scans while watching the Inscapes movie. Regional homogeneity (ReHo) maps were created from the fMRI data, and multiple regression analysis was performed to assess the relation between maternal sensitivity and ReHo. Maternal sensitivity at the age of 8 months was positively associated with children's ReHo values within the medial prefrontal cortex. Distal connectivity of this region showed no significant association with maternal sensitivity in a seed-based connectivity analysis. No associations were found between maternal sensitivity during toddlerhood and brain functional connectivity. Together, these results suggest that maternal sensitivity, especially in infancy, may influence offspring brain functional connectivity. However, studies with larger sample sizes are warranted
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