Subtle Visuomotor deficits and reduced benefit from practice in early treated phenylketonuria

Introduction: Phenylketonuria (PKU) is a rare metabolic disease that causes slight-to-severe neurological symptoms. Slow performance has been observed in PKU but the influence of high-order (i.e., not purely motor) deficits and of temporary variations of the phenylalanine (Phe) level on this slowness has not been fully corroborated as yet. Response speed and the effect of motor practice during the performance of a visuomotor coordination task were measured, in a group of patients with early-treated phenylketonuria (ET PKU). Method: We compared the performance of a group of early-treated PKU patients with ages ranging from 11 to 25 years and a control group of healthy volunteers on a computerized visuomotor task. Participants performed rapid movements towards one of five response buttons, as indicated by a visual stimulus that could appear in five different positions on a computer screen. The results of our visuomotor task were correlated with neurobiological data (Phe levels) and with neuropsychological measures of motor (finger tapping) and executive functions (Stroop task). Results: The ET PKU group showed slower responses than the control group. Furthermore, an absence of a practice effect (i.e., faster response times at the end of the study) was found in the PKU group but not in the control group. Our results also revealed that this absence of practice effect correlated with higher Phe levels on the testing day with respect to the average Phe level of the previous 12 months and, although weakly, with performance on the Stroop task. Conclusions: This pattern of results indicates slower visuomotor performance and a less beneficial effect of practice in ET PKU. The correlations found among our visuomotor measures, the same-day Phe level, and the Stroop test may reflect the negative effects of dopamine reduction in brain areas involved in motor control, selective attention, and learnin

Argentina como tema o alcance geográfico de la investigación : Una mirada desde SciELO y Scopus

This study makes an original knowledge contribution about the presence and characteristics of the scientific production for the period 2008-2012 which has Argentina as study object in visible researches in regional (Scielo) and international (Scopus) databases, and provides a feasible methodology to be used for studies that aims enquire into dynamics and patrons of the knowledge production on topic of national and international scope. Using the bibliometric method the production's size indicator was calculated from the count of documents for each year of the studied period, was analyzed the disciplinary and regional distribution according to the MINCyT's thematic classification, was studied the geographic origin of the signing authors of the publications and the rates of national and international collaboration were calculated. Finally, the relationship between the origin region of the Argentinian authors and the studied geographical regions of Argentina was analyzed

Excreción prolongada de Escherichia coli productor de toxina Shiga en niños que concurren a jardines maternales de Argentina

En el presente trabajo se describe la detección y el tiempo de excreción de Escherichia coli productor de toxina Shiga (STEC) O157 y no-O157 en casos sintomáticos y asintomáticos durante cuatro eventos ocurridos en jardines maternales de Argentina. En cada evento se identificaron los casos entre los niños, sus familiares y el personal del jardín. Los aislamientos fueron caracterizados por técnicas feno-genotípicas y de subtipificación. La excreción de STEC fue, en general, prolongada e intermitente. Cepas STEC O157:H7 (1er evento); O26:H11 (2do evento); O26:H11 (3er evento) y O145:NM (4to evento) fueron excretadas durante 23-30, 37, 31 y 19 días, respectivamente. Dadas las características de la excreción, no debe permitirse el reingreso a la institución de todo niño o adulto con infección por STEC, sintomático o asintomático, hasta no tener dos coprocultivos negativos sucesivos, con intervalos de 48 horas entre ellos.In this report we describe the detection and duration of fecal shedding of Shiga toxin-producing Escherichia coli (STEC) O157 and non-O157 in symptomatic and asymptomatic cases during four events occurred among children in day-care centers in Argentina. In each event, the cases were identified among children, family contacts and staff members of the Institution. The isolates were characterized by pheno-genotyping and subtyping methods. The STEC fecal shedding was prolonged and intermittent. Strains O157:H7 (1st event); O26:H11 (2nd event); O26:H11 (3rd event) and O145:NM (4th event) were shed during 23-30, 37, 31 and 19 days, respectively. Considering the possibility of STEC intermittent long-term shedding, symptomatic and asymptomatic individuals should be excluded from the Institution until two consecutive stool cultures obtained at least 48 h apart, test negative.Instituto de Genética Veterinari

Excreción prolongada de Escherichia coli productor de toxina Shiga en niños que concurren a jardines maternales de Argentina

En el presente trabajo se describe la detección y el tiempo de excreción de Escherichia coli productor de toxina Shiga (STEC) O157 y no-O157 en casos sintomáticos y asintomáticos durante cuatro eventos ocurridos en jardines maternales de Argentina. En cada evento se identificaron los casos entre los niños, sus familiares y el personal del jardín. Los aislamientos fueron caracterizados por técnicas feno-genotípicas y de subtipificación. La excreción de STEC fue, en general, prolongada e intermitente. Cepas STEC O157:H7 (1er evento); O26:H11 (2do evento); O26:H11 (3er evento) y O145:NM (4to evento) fueron excretadas durante 23-30, 37, 31 y 19 días, respectivamente. Dadas las características de la excreción, no debe permitirse el reingreso a la institución de todo niño o adulto con infección por STEC, sintomático o asintomático, hasta no tener dos coprocultivos negativos sucesivos, con intervalos de 48 horas entre ellos.In this report we describe the detection and duration of fecal shedding of Shiga toxin-producing Escherichia coli (STEC) O157 and non-O157 in symptomatic and asymptomatic cases during four events occurred among children in day-care centers in Argentina. In each event, the cases were identified among children, family contacts and staff members of the Institution. The isolates were characterized by pheno-genotyping and subtyping methods. The STEC fecal shedding was prolonged and intermittent. Strains O157:H7 (1st event); O26:H11 (2nd event); O26:H11 (3rd event) and O145:NM (4th event) were shed during 23-30, 37, 31 and 19 days, respectively. Considering the possibility of STEC intermittent long-term shedding, symptomatic and asymptomatic individuals should be excluded from the Institution until two consecutive stool cultures obtained at least 48 h apart, test negative.Instituto de Genética Veterinari

Improving the tokenisation of identifier names

Identifier names are the main vehicle for semantic information during program comprehension. For tool-supported program comprehension tasks, including concept location and requirements traceability, identifier names need to be tokenised into their semantic constituents. In this paper we present an approach to the automated tokenisation of identifier names that improves on existing techniques in two ways. First, it improves the tokenisation accuracy for single-case identifier names and for identifier names containing digits, which existing techniques largely ignore. Second, performance gains over existing techniques are achieved using smaller oracles, making the approach easier to deploy. Accuracy was evaluated by comparing our algorithm to manual tokenizations of 28,000 identifier names drawn from 60 well-known open source Java projects totalling 16.5 MSLOC. Moreover, the projects were used to perform a study of identifier tokenisation features (single case, camel case, use of digits, etc.) per object-oriented construct (class names, method names, local variable names, etc.), thus providing an insight into naming conventions in industrial-scale object-oriented code. Our tokenisation tool and datasets are publicly available

Spin pumping in magnetic trilayer structures with an MgO barrier

We present a study of the interaction mechanisms in magnetic trilayer structures with an MgO barrier grown by molecular beam epitaxy. The interlayer exchange coupling, A ex, is determined using SQUID magnetometry and ferromagnetic resonance (FMR), displaying an unexpected oscillatory behaviour as the thickness, t MgO, is increased from 1 to 4 nm. Transmission electron microscopy confirms the continuity and quality of the tunnelling barrier, eliminating the prospect of exchange arising from direct contact between the two ferromagnetic layers. The Gilbert damping is found to be almost independent of the MgO thickness, suggesting the suppression of spin pumping. The element-specific technique of X-ray detected FMR reveals a small dynamic exchange interaction, acting in concert with the static interaction to induce coupled precession across the multilayer stack. These results highlight the potential of spin pumping and spin transfer torque for device applications in magnetic tunnel junctions relying on commonly used MgO barriers

Understanding first-year students’ curiosity and interest about physics : Lessons learned from the HOPE project

This paper focuses on results of an interview based survey of first-year university physics students, carried out within the EU Horizons in Physics Education (HOPE) project (http://hopenetwork.eu/). 94 interviews conducted in 13 universities have been analyzed to investigate the factors that inspire young people to study physics. In particular, the main motivational factor, which was proven to consist of personal interest and curiosity, was unfolded into different categories and detailed interest profiles were produced. The results are arguably useful to help academic curriculum developers and teaching personnel in physics departments to provide guidance to students in developing and focusing their interest towards specific sub-fields and/or to design targeted recruitment and outreach initiatives.Peer reviewe

Posterior cortical atrophy and Alzheimer’s disease : a meta-analytic review of neuropsychological and brain morphometry studies

This paper presents the first systematic review and meta-analysis of neuropsychological and brain morphometry studies comparing posterior cortical atrophy (PCA) to typical Alzheimer's disease (tAD). Literature searches were conducted for brain morphometry and neuropsychological studies including a PCA and a tAD group. Compared to healthy controls (HC), PCA patients exhibited significant decreases in temporal, occipital and parietal gray matter (GM) volumes, whereas tAD patients showed extensive left temporal atrophy. Compared to tAD patients, participants with PCA showed greater GM volume reduction in the right occipital gyrus extending to the posterior lobule. In addition, PCA patients showed less GM volume loss in the left parahippocampal gyrus and left hippocampus than tAD patients. PCA patients exhibit significantly greater impairment in Immediate Visuospatial Memory as well as Visuoperceptual and Visuospatial Abilities than patients with tAD. However, tAD patients showed greater impairment in Delayed Auditory/Verbal Memory than patients with PCA. PCA is characterized by significant atrophy of the occipital and parietal regions and severe impairments in visuospatial functioning.JA is funded by a doctoral grant from the Foundation for Science and Technology, FCT (SFRH/BD/64457/2009, co-funded by FSE/POPH). JA and AS are funded by project PIC/IC/83290/2007, which is supported by FEDER (POFC-COMPETE) and FCT. JMS is supported by a fellowship of the project SwitchBox-FP7-HEALTH-2010-grant 259772-2. These organizations had no role in the study design, data collection, analysis, interpretation, or in the decision to submit the paper for publication