Limits to tDCS effects in language:failures to modulate word production in healthy participants with frontal or temporal tDCS

Transcranial direct current stimulation (tDCS) is a method of non-invasive brain stimulation widely used to modulate cognitive functions. Recent studies, however, suggests that effects are unreliable, small and often non-significant at least when stimulation is applied in a single session to healthy individuals. We examined the effects of frontal and temporal lobe anodal tDCS on naming and reading tasks and considered possible interactions with linguistic activation and selection mechanisms as well possible interactions with item difficulty and participant individual variability. Across four separate experiments (N, Exp 1A = 18; 1B = 20; 1C = 18; 2 = 17), we failed to find any difference between real and sham stimulation. Moreover, we found no evidence of significant effects limited to particular conditions (i.e., those requiring suppression of semantic interference), to a subset of participants or to longer RTs. Our findings sound a cautionary note on using tDCS as a means to modulate cognitive performance. Consistent effects of tDCS may be difficult to demonstrate in healthy participants in reading and naming tasks, and be limited to cases of pathological neurophysiology and/or to the use of learning paradigms

Airborne Measurements of Gravity Wave Breaking at the Tropopause

2000 FLORIDA AVE NW, WASHINGTON, DC, 2000

Organization and oscillations in simulated shallow convective clouds

Physical insights into processes governing temporal organization and evolution of cloud fields are of great importance for climate research. Here using large eddy simulations with a bin microphysics scheme, we show that warm convective cloud fields exhibit oscillations with two distinct periods (~10 and ~90 min, for the case studied here). The shorter period dominates the nonprecipitating phase, and the longer period is related to the precipitating phase. We show that rain processes affect the domain\u27s thermodynamics, hence forcing the field into a low‐frequency recharge‐discharge cycle of developing cloudiness followed by precipitation‐driven depletion. The end result of precipitation is stabilization of the lower atmosphere by warming of the cloudy layer (due to latent heat release) and cooling of the subcloud layer (by rain evaporation, creating cold pools). As the thermodynamic instability weakens, so does the cloudiness, and the rain ceases. During the nonprecipitating phase of the cycle, surface fluxes destabilize the boundary layer until the next precipitation cycle. Under conditions that do not allow development of precipitation (e.g., high aerosol loading), high‐frequency oscillations dominate the cloud field. Clouds penetrating the stable inversion layer trigger gravity waves with a typical period of ~10 min. In return, the gravity waves modulate the clouds in the field by modifying the vertical velocity, temperature, and humidity fields. Subsequently, as the polluted nonprecipitating simulations evolve, the thermodynamic instability increases and the cloudy layer deepens until precipitation forms, shifting the oscillations from high to low frequency. The organization of cold pools and the spatial scale related to these oscillations are explored

Quality of life in alopecia areata: A disease-specific questionnaire

Background Alopecia areata (AA) is an autoimmune disease affecting about 2% of the population, which has a considerable impact on quality of life (QoL). There are no disease-specific questionnaires to assess QoL in patients suffering from AA. Objective To validate a new disease-specific questionnaire for AA, named AA-QLI, and to compare the consequent Quality of Life Index (QLI) with the commonly known Dermatology Life Quality Index (DLQI) to verify if it can provide a more comprehensive tool for patients. Methods A total of 50 patients affected by AA were administered both the AA-QLI, created by us, and the well-known DLQI. With the aim to detect suitable QLI, we propose to use two multivariate analyses: a principal component analysis approach on the data collected with both questionnaires to compare their capability to measure the QoL; a structural equation modelling on our AA-QLI to identify which category of symptoms mostly affects the QoL. Results The scores of both the questionnaires are quite close, except for a few cases. Statistical analysis shows a higher specificity of the AA-QLI for evaluating QoL. Among the three areas in which AA-QLI is divided, 'Relationship' has a major impact on the QLI, followed by 'Subjective symptoms'; 'Objective signs' has a lower weight on the QLI. Conclusion AA-QLI is a good instrument to evaluate the real impact of AA on QoL. It can be helpful both for the physician and for the patient. © 2012 European Academy of Dermatology and Venereology

Gender-Related Differences in the Relationships Between Blood Pressure, Age, and Body Size in Prepubertal Children

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Drugs and health in the Brazilian press: an analysis of articles published in newspapers and magazines

This article analyzes information recently published by the Brazilian press on the use of psychoactive drugs and its implications on health. A sample of 502 newspaper and magazine articles published in 1998 was researched using content analysis. The drugs most frequently featured in the headlines were tobacco (18.1%), coca-derived drugs (9.2%), marijuana (9.2%), alcoholic beverages (8.6%), and anabolic steroids (7.4%). Solvents were featured in only one article, although they are the most commonly used drug in Brazil, second only to alcohol and tobacco. These data indicate an imbalance between the journalistic approach and the epidemiological profile of psychoactive drug consumption in Brazil. Dependence was the most frequent consequence mentioned in the articles (46%), followed by violence (9.2%), withdrawal syndrome (8.0%), and AIDS (6.8%). The focus of the articles varied according to the drug in question. While articles on marijuana focused on its therapeutic use and legalization, those on cocaine-related issues discussed both the damage caused by consumption as well as various interventions (treatment and repression).O presente estudo analisa as informações que a imprensa escrita vem divulgando atualmente no Brasil sobre as implicações do uso de drogas para a saúde. Por meio de análise de conteúdo, foi pesquisada uma amostra de 502 artigos divulgados ao longo do ano de 1998 em jornais e revistas. Entre os psicotrópicos mais evidenciados nas manchetes, destacaram-se o cigarro comum (18,1%), derivados da coca (9,2%), maconha (9,2%), bebidas alcoólicas (8,6%) e anabolizantes (7,4%). Em contrapartida, os solventes, que são os psicotrópicos mais usados no Brasil (excetuando-se o álcool e o tabaco), foram evidenciados em apenas um artigo. Esses dados indicam um descompasso entre o enfoque jornalístico e o perfil epidemiológico do consumo de psicotrópicos no Brasil. A dependência foi a conseqüência mencionada com maior freqüência nos artigos (46%), seguida de violência (9,2%), síndrome de abstinência (8,0%) e AIDS (6,8%). Os artigos apresentaram diferentes enfoques de acordo com a droga em questão; por exemplo, enquanto para a maconha prevaleceram os artigos sobre o seu uso terapêutico e a descriminalização, para a cocaína predominaram temas relacionados aos danos decorrentes do uso, ao tratamento e à repressão.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PsicobiologiaUNIFESP, EPM, Depto. de PsicobiologiaSciEL

How neuronal migration contributes to the morphogenesis of the CNS: insights from the zebrafish

We used transgenic zebrafish expressing GFP or YFP in subpopulations of neurons to study the migration, homing process and axon extension of groups of CNS neurons in different regions of the zebrafish brain. We found that extensive migration takes place at all levels of the CNS and gives rise to nuclei or cell populations with specific identities. Here, we describe 4 previously unknown or only partially characterized migratory events taking place in the zebrafish telencephalon and rhombic lip, using 3 different transgenic lines, and identify the phenotypes of the cells undertaking these migrations. The migration of a subgroup of mitral cell precursors from the dorsocaudal telencephalon to the olfactory bulb, visualized in the tg(tbr1:YFP) transgenic line, is coupled with morphogenetic transformation of the dorsal telencephalon. The tg(1.4dlx5a-6a:GFP) transgenic line provides a means to analyze the migration of GABAergic interneurons from the ventral to the dorsal telencephalon, thus extending the occurrence of this migration to another vertebrate. The tg(Xeom:GFP) transgenic line provides the first demonstration of the dorsoventral migration of glutamatergic septal neurons, present in mammals and now described in fish, thus reconciling the contrasting evidence of dorsal patterning genes (tbr1, eomes) expressed in a ventral cell population. Furthermore, migration studies in the tg(1.4dlx5a-6a:GFP) and tg(Xeom:GFP) lines help determine the origin of 2 important cell populations in the fish cerebellum: projection neurons and Purkinje cells. These examples reinforce the concept that migratory events contribute to the distribution of cell types with diverse identities through the CNS and that zebrafish transgenic lines represent excellent tools to study these events. Copyrigh

The high-redshift gamma-ray burst GRB140515A

High-redshift gamma-ray bursts have several advantages for the study of the distant universe, providing unique information about the structure and properties of the galaxies in which they exploded. Spectroscopic identification with large ground-based telescopes has improved our knowledge of the class of such distant events. We present the multi-wavelength analysis of the high-$z$ Swift gamma-ray burst GRB140515A ($z = 6.327$). The best estimate of the neutral hydrogen fraction of the intergalactic medium (IGM) towards the burst is $x_{HI} \leq 0.002$. The spectral absorption lines detected for this event are the weakest lines ever observed in gamma-ray burst afterglows, suggesting that GRB140515A exploded in a very low density environment. Its circum-burst medium is characterised by an average extinction (A$_{\rm V} \sim 0.1$) that seems to be typical of $z \ge 6$ events. The observed multi-band light curves are explained either with a very flat injected spectrum ($p = 1.7$) or with a multi-component emission ($p = 2.1$). In the second case a long-lasting central engine activity is needed in order to explain the late time X-ray emission. The possible origin of GRB140515A from a Pop III (or from a Pop II stars with local environment enriched by Pop III) massive star is unlikely.Comment: 10 pages, 8 figures, 5 tables, submitted to Astronomy & Astrophysic