Magnetic Discontinuities in Magnetohydrodynamic Turbulence and in the Solar Wind

Recent measurements of solar wind turbulence report the presence of intermittent, exponentially distributed angular discontinuities in the magnetic field. In this Letter, we study whether such discontinuities can be produced by magnetohydrodynamic (MHD) turbulence. We detect the discontinuities by measuring the fluctuations of the magnetic field direction, Delta theta, across fixed spatial increments Delta x in direct numerical simulations of MHD turbulence with an imposed uniform guide field B_0. A large region of the probability density function (pdf) for Delta theta is found to follow an exponential decay, proportional to exp(-Delta theta/theta_*), with characteristic angle theta_* ~ (14 deg) (b_rms/B_0)^0.65 for a broad range of guide-field strengths. We find that discontinuities observed in the solar wind can be reproduced by MHD turbulence with reasonable ratios of b_rms/B_0. We also observe an excess of small angular discontinuities when Delta x becomes small, possibly indicating an increasing statistical significance of dissipation-scale structures. The structure of the pdf in this case closely resembles the two-population pdf seen in the solar wind. We thus propose that strong discontinuities are associated with inertial-range MHD turbulence, while weak discontinuities emerge from near-dissipation-range turbulence. In addition, we find that the structure functions of the magnetic field direction exhibit anomalous scaling exponents, which indicates the existence of intermittent structures.Comment: To appear in Physical Review Letter

Language Characteristics of Individuals with Down Syndrome

On average, language and communication characteristics of individuals with Down syndrome (the most common genetic cause of intellectual disability) follow a consistent profile. Despite considerable individual variability, receptive language is typically stronger than expressive language, with particular challenges in phonology and syntax. We review the literature on language and literacy skills of individuals with Down syndrome, with emphasis on the areas of phonology, vocabulary, syntax, and pragmatics. We begin by describing the hearing, oral-motor, cognitive, social, and prelinguistic and early nonverbal communication characteristics of individuals with Down syndrome. We conclude with a discussion of clinical implications and research directions

Narrative skill in boys with fragile X syndrome with and without autism spectrum disorder

We examined recalled narratives of boys with fragile X syndrome with autism spectrum disorder (FXS-ASD; N=28) and without ASD (FXS-O; N=29), and compared them to those of boys with Down syndrome (DS; N=33) and typically developing boys (TD; N=39). Narratives were scored for mentions of macrostructural Story Grammar elements (Introduction, Relationship, Initiating Events, Internal Response, Attempts/Actions, and Ending). We found that narrative recall is predicted by short-term memory and nonverbal mental age levels in almost all groups (except TD), but not by expressive syntax or caregiver education. After adjusting for these covariates, there were no differences between the three groups with intellectual disability (ID). The FXS-ASD group, however, had significantly poorer performance than the TD group on the overall Story Grammar score, and both the FXS-O and FXS-ASD groups had lower Attempts/Actions scores than the TD group. We conclude that some form of narrative impairment may be associated with FXS, that this impairment may be shared by other forms of ID, and that the presence of ASD has a significantly detrimental effect on narrative recall

Longitudinal Profiles of Expressive Vocabulary, Syntax, and Pragmatic Language in Boys with Fragile X Syndrome or Down Syndrome

Fragile X syndrome (FXS) and Down syndrome (DS) are the two leading genetic causes of intellectual disability, and FXS is the most common known genetic condition associated with autism. Both FXS and DS are associated with significant language impairment, but little is known about expressive language across domains over time or the role of autism in language development in FXS

Précarité et nouvelles formes d'emploi : quatre études sectorielles en région Rhône-Alpes : bilan qualitatif : mars 2008-décembre 2008

Ce rapport propose de cerner ce qu'est la précarité d'une part, et d'approfondir les différentes réalités de cette précarité d'autre part. La première partie du rapport permettra d'approcher cette réalité complexe qu'est la précarité dans l'emploi. Développer le dialogue social territorial sur la précarité dans l'emploi nécessite de disposer d'une vision commune de sa nature, de ses développements et de ses enjeux. Dans une seconde partie, des diagnostics très poussés dans chacun des secteurs retenus, à savoir la logistique, les services à la personne, le tourisme-loisir, les pôles de compétitivité, sont développés. Le programme sur la précarité et les nouvelles formes d'emploi essaie de croiser les réalités constatées dans ces quatre secteurs de l'économie et quatre régions européennes (Rhône-Alpes, Lombardie, Catalogne, Bade-Wurtemberg).précarité ; emploi ; analyse sectorielle ; travail précaire ; travailleur saisonnier ; condition de travail ; France ; Italie ; Espagne ; Allemagne ; Rhône-Alpes ; Lombardie ; Catalogne ; Bade-Wurtemberg

Cognitive, Environmental, and Linguistic Predictors of Syntax in Fragile X Syndrome and Down Syndrome

We examined which cognitive, environmental, and speech/language variables predict expressive syntax in boys with fragile X syndrome (FXS), Down syndrome (DS), and typical development (TD), and whether predictive relationships differed by group

Clinically early-stage CSPα mutation carrier exhibits remarkable terminal stage neuronal pathology with minimal evidence of synaptic loss

Autosomal dominant adult-onset neuronal ceroid lipofuscinosis (AD-ANCL) is a multisystem disease caused by mutations in the DNAJC5 gene. DNAJC5 encodes Cysteine String Protein-alpha (CSPα), a putative synaptic protein. AD-ANCL has been traditionally considered a lysosomal storage disease based on the intracellular accumulation of ceroid material. Here, we report for the first time the pathological findings of a patient in a clinically early stage of disease, which exhibits the typical neuronal intracellular ceroid accumulation and incipient neuroinflammation but no signs of brain atrophy, neurodegeneration or massive synaptic loss. Interestingly, we found minimal or no apparent reductions in CSPα or synaptophysin in the neuropil. In contrast, brain homogenates from terminal AD-ANCL patients exhibit significant reductions in SNARE-complex forming presynaptic protein levels, including a significant reduction in CSPα and SNAP-25. Frozen samples for the biochemical analyses of synaptic proteins were not available for the early stage AD-ANLC patient. These results suggest that the degeneration seen in the patients with AD-ANCL reported here might be a consequence of both the early effects of CSPα mutations at the cellular soma, most likely lysosome function, and subsequent neuronal loss and synaptic dysfunction

Expressive morphosyntax in boys with Fragile X syndrome with and without autism spectrum disorder

Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability, and the most common single gene disorder associated with autism. Language impairments in this disorder are well documented, but the nature and extent of syntactic impairments are still unclear

Clinical performance of an infliximab rapid quantification assay

Background: Therapeutic drug monitoring (TDM)-based algorithms can be used to guide infliximab (IFX) adjustments in inflammatory bowel disease (IBD) patients. This study aimed to explore a rapid IFX-quantification test from a clinical perspective. Methods: This manuscript describes a prospective cohort study involving 110 ulcerative colitis (UC) patients on the maintenance phase of IFX. IFX trough levels were quantified using a rapid quantification assay and a commonly-used reference kit. Results: Irrespective of the assay used to measure IFX, its through levels were statistically different between patients with and without endoscopic remission (Mayo endoscopic score = 0), as well as between patients stratified by their faecal calprotectin (FC) levels. Despite the fact that the two methods correlated well with each other [Spearman's rank correlation coefficient = 0.843, p < 0.001; intraclass correlation coefficients = 0.857, 95% confidence interval (CI): 0.791-0.903], there was a discernible systematic variation; values obtained with the reference kit were on average 2.62 units higher than those obtained with the rapid assay. Notwithstanding, 3 mu g/ml was shown to be an acceptable cut-off to assess endoscopic status and inflammatory burden levels using both assays. The percentage of patients that had a positive outcome when the IFX concentration measured by the rapid assay ranked above 3 mu g/ml was 88% both for a Mayo endoscopic score <= 1 and for an FC concentration <250 mu g/g. Conclusions: Based on this study, we concluded that using the rapid IFX assessment system with a 3 mu g/ml threshold is a reliable alternative to the time-consuming enzyme-linked immunosorbent assays in patients on the maintenance phase of IFX.Portuguese IBD Group (GEDII, Grupo de Estudo da Doenca Inflamatoria Intestinal)info:eu-repo/semantics/publishedVersio