269 research outputs found

    Spatial and verbal routes to number comparison in young children

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    The ability to compare the numerical magnitude of symbolic numbers represents a milestone in the development of numerical skills. However, it remains unclear how basic numerical abilities contribute to the understanding of symbolic magnitude and whether the impact of these abilities may vary when symbolic numbers are presented as number words (e.g., \u201csix vs. eight\u201d) vs. Arabic numbers (e.g., 6 vs. 8). In the present study on preschool children, we show that comparison of number words is related to cardinality knowledge whereas the comparison of Arabic digits is related to both cardinality knowledge and the ability to spatially map numbers. We conclude that comparison of symbolic numbers in preschool children relies on multiple numerical skills and representations, which can be differentially weighted depending on the presentation format. In particular, the spatial arrangement of digits on the number line seems to scaffold the development of a \u201cspatial route\u201d to understanding the exact magnitude of numerals

    Forecasting longitudinal growth in children's numerical abilities

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    Modern society requires individuals to possess solid numerical skills to succeed in everyday life (Gerardi et al., 2013). Understanding the cognitive and neural markers of early numerical skills could provide much needed information about the development of long-term mathematical capabilities, and inform early intervention for those at risk of mathematical learning disability. In this regard, a longitudinal approach can disentangle whether specific brain networks and cognitive processes are predictive, rather than the consequential effect, of mathematical achievement

    The relation between parietal GABA concentration and numerical skills

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    Several scientific, engineering, and medical advancements are based on breakthroughs made by people who excel in mathematics. Our current understanding of the underlying brain networks stems primarily from anatomical and functional investigations, but our knowledge of how neurotransmitters subserve numerical skills, the building block of mathematics, is scarce. Using 1H magnetic resonance spectroscopy (N = 54, 3T, semi-LASER sequence, TE = 32 ms, TR = 3.5 s), the study examined the relation between numerical skills and the brain's major inhibitory (GABA) and excitatory (glutamate) neurotransmitters. A negative association was found between the performance in a number sequences task and the resting concentration of GABA within the left intraparietal sulcus (IPS), a key region supporting numeracy. The relation between GABA in the IPS and number sequences was specific to (1) parietal but not frontal regions and to (2) GABA but not glutamate. It was additionally found that the resting functional connectivity of the left IPS and the left superior frontal gyrus was positively associated with number sequences performance. However, resting GABA concentration within the IPS explained number sequences performance above and beyond the resting frontoparietal connectivity measure. Our findings further motivate the study of inhibition mechanisms in the human brain and significantly contribute to our current understanding of numerical cognition's biological bases

    The expression of a bean PGIP in transgenic wheat confers increased resistance to the fungal pathogen Bipolaris sorokiniana

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    In several plant-pathogen interactions to overcome the barrier represented by cell wall most fungal pathogens produce a variety of hydrolytic enzymes and between them PGs are one of the first to be secreted. We demonstrate that transgenic wheat plants expressing PvPGIP2 showed a significant reduction of symptoms following the infection of Bipolaris sorokiniana suggesting that pectin hydrolysis is an important step for fungal penetration of wheat plants.In molti sistemi pianta patogeno i patogeni al fine di superare l’ostacolo rappresentato dalla parete cellulare producono degli enzimi idrolitici tra cui le Poligalatturonasi ( PG) sono tra i primi ad essere secreti. In questo lavoro dimostriamo che piante transgeniche di frumento sovraesprimenti la PvPGIP2 mostrano una significativa riduzione nella sintomatologia riscontrata in seguito ad infezione con Bipolaris sorokiniana suggerendo che l’idrolisi della pectina rappresenta uno step importante per la penetrazione e la colonizzazione dei tessuti di frumento.L'articolo é disponibile sul sito dell'editore: http://www.apsjournals.apsnet.or

    Predicting learning and achievement using GABA and glutamate concentrations in human development

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    Previous research has highlighted the role of glutamate and gamma-aminobutyric acid (GABA) in learning and plasticity. What is currently unknown is how this knowledge translates to real-life complex cognitive abilities that emerge slowly and how the link between these neurotransmitters and human learning and plasticity is shaped by development. While some have suggested a generic role of glutamate and GABA in learning and plasticity, others have hypothesized that their involvement shapes sensitive periods during development. Here we used a cross-sectional longitudinal design with 255 individuals (spanning primary school to university) to show that glutamate and GABA in the intraparietal sulcus explain unique variance both in current and future mathematical achievement (approximately 1.5 years). Furthermore, our findings reveal a dynamic and dissociable role of GABA and glutamate in predicting learning, which is reversed during development, and therefore provide novel implications for models of learning and plasticity during childhood and adulthood

    Physical activity intervention for elderly patients with reduced physical performance after acute coronary syndrome (HULK study): Rationale and design of a randomized clinical trial

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    Background: Reduced physical performance and impaired mobility are common in elderly patients after acute coronary syndrome (ACS) and they represent independent risk factors for disability, morbidity, hospital readmission and mortality. Regular physical exercise represents a means for improving functional capacity. Nevertheless, its clinical benefit has been less investigated in elderly patients in the early phase after ACS. The HULK trial aims to investigate the clinical benefit of an early, tailored low-cost physical activity intervention in comparison to standard of care in elderly ACS patients with reduced physical performance. Design: HULK is an investigator-initiated, prospective multicenter randomized controlled trial (NCT03021044). After successful management of the ACS acute phase and uneventful first 1 month, elderly (≥70 years) patients showing reduced physical performance are randomized (1:1 ratio) to either standard of care or physical activity intervention. Reduced physical performance is defined as a short physical performance battery (SPPB) score of 4-9. The early, tailored, low-cost physical intervention includes 4 sessions of physical activity with a supervisor and an home-based program of physical exercise. The chosen primary endpoint is the 6-month SPPB value. Secondary endpoints briefly include quality of life, on-treatment platelet reactivity, some laboratory data and clinical adverse events. To demonstrate an increase of at least one SPPB point in the experimental arm, a sample size of 226 patients is needed. Conclusions: The HULK study will test the hypothesis that an early, tailored low-cost physical activity intervention improves physical performance, quality of life, frailty status and outcome in elderly ACS patients with reduced physical performance

    Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

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    IntroductionTranscatheter aortic valve implantation (TAVI) has become an alternative to surgical replacement of the aortic valve elderly patients. However, TAVI patients may suffer from paravalvular leaks (PVL). Detecting and grading is usually done by echocardiography, but is limited by resolution, 2D visualization and operator dependency. 4D flow magnetic resonance imaging (MRI) is a promising alternative, which did not reach clinical application in TAVI patients. The aim of this study was applying 3D printing technologies in order to evaluate flow patterns and hemodynamics of PVLs following TAVI, exploiting 4D flow MRI and standard ultrasound. Materials and methodsAn MR-compatible, anatomically left ventricle, aortic root, and ascending aorta model was fabricated by combining 3D-printed parts and various soft silicone materials to match physiological characteristics. An Abbott Portico (TM) valve was used in continuous antegrade flow (12-22 l/min), retrograde flow with varying transvalvular pressures (60-110 mmHg), and physiological pulsatile hemodynamics (aortic pressure: 120/80 mmHg, cardiac output: 5 l/min) Time-resolved MR measurements were performed above and below the TAVI stent and compared with color Doppler ultrasound measurements in exactly the same setup. ResultsThe continuous antegrade flow measurements from MRI largely agreed with the flowmeter measurements, and a maximum error of only 7% was observed. In the retrograde configuration, visualization of the paravalvular leaks was possible from the MR measurements, but flow was overestimated by up to 33%. The 4D MRI measurement in the pulsatile setup revealed a single main PVL, which was also confirmed by the color Doppler measurements, and velocities were similar (2.0 m/s vs. 1.7 m/s). Discussion4D MRI techniques were used to qualitatively assess flow in a patient-specific, MR-compatible and flexible model, which only became possible through the use of 3D printing techniques. Flow patterns in the ascending aorta, identification and quantification of PVLs was possible and the location and extent of PVLs were confirmed by ultrasound measurements. The 4D MRI flow technique allowed evaluation of flow patterns in the ascending aorta and the left ventricle below the TAVI stent with good results in identifying PVLs, demonstrating its capabilities over ultrasound by providing the ability to visualize the paravalvular jets in three dimensions at however, additional expenditure of time and money

    Generation of mesenchymal stromal cells from cord blood: evaluation of in vitro quality parameters prior to clinical use

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    Dexamethasone scheduling in MNC culture. The supplement was added in standard medium until the detection of MSC colonies (n = 16 CB units) or alternatively added for the first week of MNC culture only (n = 34). (DOCX 120 kb

    Erector Spinae Plane Block and Chronic Pain: An Updated Review and Possible Future Directions

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    : Chronic pain is a common, pervasive, and often disabling medical condition that affects millions of people worldwide. According to the Global Burden of Disease survey, painful chronic conditions are causing the largest numbers of years lived with disability worldwide. In America, more than one in five adults experiences chronic pain. Erector spinae plane block is a novel regional anesthesia technique used to provide analgesia with multiple possible uses and a relatively low learning curve and complication rate. Here, we review the erector spinae plane block rationale, mechanism of action and possible complications, and discuss its potential use for chronic pain with possible future directions for research
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