52 research outputs found
Exposure to linguistic labels during childhood modulates the neural architecture of race categorical perception
Perceptually categorizing a face to its racial belonging may have important consequences on interacting with people. However, race categorical perception (CP) has been scarcely investigated nor its developmental pathway. In this study, we tested the neurolinguistics rewiring hypothesis, stating that language acquisition modulates the brain processing of social perceptual categories. Accordingly, we investigated the electrophysiological correlates of race CP in a group of adults and children between 3 and 5 years of age. For both groups we found a greater modulation of the N400 connected with the processing of between category boundaries (i.e., faces belonging to different race groups) than within-category boundaries (i.e., different faces belonging to the same race group). This effect was the same in both adults and children, as shown by the comparable between-group amplitude of the differential wave (DW) elicited by the between-category faces. Remarkably, this effect was positively correlated with racial-labels acquisition, but not with age, in children. Finally, brain source analysis revealed the activation of a more modularized cortical network in adults than in children, with unique activation of the left superior temporal gyrus (STG) and the inferior frontal gyrus (IFG), which are areas connected to language processing. These are the first results accounting for an effect of language in rewiring brain connectedness when processing racial categories
The Polar Cloud Satellite: The First CubeSat Mission to Study Noctilucent Clouds
Members of the Spaceflight Sciences, Policy, and Operations Club (SSPOC) are designing a 1U CubeSat, the Polar Cloud Satellite, that will host an ultraviolet instrument that will image noctilucent clouds. Noctilucent clouds, formally called polar mesospheric clouds (PMCs), are clouds made of ice particles and water vapor that form in the polar regions of the Earth at altitudes ranging from 76 to 85 kilometers. The formation of PMCs at much lower latitudes than usual since their discovery in the 1980s can possibly be linked to increased carbon dioxide output by humans. NASAâs Aeronomy of Ice in the Mesosphere (AIM) satellite was launched in 2007 to study these clouds and how they form. Our team plans to purchase and integrate an ultraviolet instrument that will be used to image PMCs, but with a much smaller satellite than AIM. We hope to collaborate with an AIM institution at some level, such as data comparison with AIMâs images. Our team will assemble and test the satellite bus and its systems, integrate the ultraviolet payload, and operate the mission from a spaceflight operations center on campus, perhaps in the College of Aviationâs Department of Applied Aviation Sciences
Measurements of the top-quark mass using charged particle tracking
We present three measurements of the top-quark mass in the lepton plus jets channel with approximately 1.9ââfbâ1 of integrated luminosity collected with the CDF II detector using quantities with minimal dependence on the jet energy scale. One measurement exploits the transverse decay length of b-tagged jets to determine a top-quark mass of 166.9+9.5â8.5(stat)±2.9(syst)ââGeV/c2, and another the transverse momentum of electrons and muons from W-boson decays to determine a top-quark mass of 173.5+8.8â8.9(stat)±3.8(syst)ââGeV/c2. These quantities are combined in a third, simultaneous mass measurement to determine a top-quark mass of 170.7±6.3(stat)±2.6(syst)ââGeV/c2.We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.âP. Sloan Foundation; the Bundesministerium fĂŒr Bildung und Forschung, Germany; the Korean Science and Engineering Foundation and the Korean Research Foundation; the Science and Technology Facilities Council and the Royal Society, UK; the Institut National de Physique Nucleaire et Physique des Particules/CNRS; the Russian Foundation for Basic Research; the Ministerio de Ciencia e InnovaciĂłn, and Programa Consolider-Ingenio 2010, Spain; the Slovak R and D Agency; and the Academy of Finland
Same-day versus rapid ART initiation in HIV-positive individuals presenting with symptoms of tuberculosis: protocol for an open-label randomized non-inferiority trial in Lesotho and Malawi
Background
In absence of contraindications, same-day initiation (SDI) of antiretroviral therapy (ART) is recommended for people testing HIV-positive who are ready to start treatment. Until 2021, World Health Organization (WHO) guidelines considered the presence of TB symptoms (presumptive TB) a contraindication to SDI due to the risk of TB-immune reconstitution inflammatory syndrome (TB-IRIS). To reduce TB-IRIS risk, ART initiation was recommended to be postponed until results of TB investigations were available, and TB treatment initiated if active TB was confirmed. In 2021, the WHO guidelines changed to recommending SDI even in the presence of TB symptoms without awaiting results of TB investigations based on the assumption that TB investigations often unnecessarily delay ART initiation, increasing the risk for pre-ART attrition from care, and noting that the clinical relevance of TB-IRIS outside the central nervous system remains unclear. However, this guideline change was not based on conclusive evidence, and it remains unclear whether SDI of ART or TB test results should be prioritized in people with HIV (PWH) and presumptive TB.
Design and methods
SaDAPT is an open-label, pragmatic, parallel, 1:1 individually randomized, non-inferiority trial comparing two strategies for the timing of ART initiation in PWH with presumptive TB (âART firstâ versus âTB results firstâ). PWH in Lesotho and Malawi, aged 12 years and older (re)initiating ART who have at least one TB symptom (cough, fever, night sweats or weight loss) and no signs of intracranial infection are eligible. After a baseline assessment, participants in the âART firstâ arm will be offered SDI of ART, while those in the âTB results firstâ arm will be offered ART only after active TB has been confirmed or refuted. We hypothesize that the âART firstâ approach is safe and non-inferior to the âTB results firstâ approach with regard to HIV viral suppression (<400 copies/ml) six months after enrolment. Secondary outcomes include retention in care and adverse events consistent with TB-IRIS.
Expected outcomes
SaDAPT will provide evidence on the safety and effects of SDI of ART in PWH with presumptive TB in a pragmatic clinical trial setting
Color categorization in infants
In human infants trichromatic vision is functional within the first few months of life. Infants also make categorical responses to color â appearing to group together similar colors, but with distinct boundaries. Recent developments have revealed a candidate neural basis for infant color categories â the low-level cone-opponent mechanisms of color vision. These pre-linguistic boundaries appear to drive infant looking behavior, and may provide discontinuity in color perception around which linguistic color categories are formed in adults. This finding opens up new avenues for research, such as the need to understand how color categorization develops from being based on the low-level mechanisms of color vision in infancy to reflecting the linguistic, cultural and visual environment of the individual
Recommendations for motion correction of infant fNIRS data applicable to data sets acquired with a variety of experimental designs and acquisition systems
Despite motion artifacts are a major source of noise in fNIRS infant data, how to approach motion correction in this population has only recently started to be investigated. Homer2 offers a wide range of motion correction methods and previous work on simulated and adult data suggested the use of Spline interpolation and Wavelet filtering as optimal methods for the recovery of trials affected by motion. However, motion artifacts in infant data differ from those in adults' both in amplitude and frequency of occurrence. Therefore, artifact correction recommendations derived from adult data might not be the optimal for infant data. We hypothesized that the combined use of Spline and Wavelet would outperform their individual use on data with complex profiles of motion artifacts. To demonstrate this, we first compared, on infant semi-simulated data, the performance of several motion correction techniques on their own and of the novel combined approach; then, we investigated the performance of Spline and Wavelet alone and in combination on real cognitive data from three datasets collected with infants of different ages (5, 7 and 10 months), with different tasks (auditory/visual and tactile) and with different NIRS systems. To quantitatively estimate and compare the efficacy of these techniques, we adopted four metrics: hemodynamic response recovery error, within-subject standard deviation, between-subjects standard deviation and number of trials that survived each correction method. Our results demonstrated that (i) it is always better correcting for motion artifacts than rejecting the corrupted trials; (ii) Wavelet filtering on its own and in combination with Spline interpolation seems to be the most effective approach in reducing the between- and the within-subject standard deviations. Importantly, the combination of Spline and Wavelet was the approach providing the best performance in semi-simulation both at low and high levels of noise, also recovering most of the trials affected by motion artifacts across all datasets, a crucial result when working with infant data. [Abstract copyright: Copyright © 2019. Published by Elsevier Inc.
The Compact Linear Collider (CLIC) - 2018 Summary Report
The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear collider under development at CERN. Following the CLIC conceptual design published in 2012, this report provides an overview of the CLIC project, its current status, and future developments. It presents the CLIC physics potential and reports on design, technology, and implementation aspects of the accelerator and the detector. CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. CLIC uses a two-beam acceleration scheme, in which 12 GHz accelerating structures are powered via a high-current drive beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments and system tests have resulted in an increased energy efficiency (power around 170 MW) for the 380 GeV stage, together with a reduced cost estimate at the level of 6 billion CHF. The detector concept has been refined using improved software tools. Significant progress has been made on detector technology developments for the tracking and calorimetry systems. A wide range of CLIC physics studies has been conducted, both through full detector simulations and parametric studies, together providing a broad overview of the CLIC physics potential. Each of the three energy stages adds cornerstones of the full CLIC physics programme, such as Higgs width and couplings, top-quark properties, Higgs self-coupling, direct searches, and many precision electroweak measurements. The interpretation of the combined results gives crucial and accurate insight into new physics, largely complementary to LHC and HL-LHC. The construction of the first CLIC energy stage could start by 2026. First beams would be available by 2035, marking the beginning of a broad CLIC physics programme spanning 25-30 years
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