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Navigating for accurate information, especially health- and science-related content, on social media has been challenging during the COVID-19 pandemic. Although infographics are a popular medium for simplifying text-based information into visual components, their usefulness during a global health crisis has not been explored. The study aims to explore the perceptions of infographics in conveying scientific information related to COVID-19 on social media. Following a social media campaign that published COVID-19 related infographics from May to August 2020, a cross-sectional survey was administered to social media users, primarily students from Western University. Several questions asked respondents to make comparisons with written articles when reporting their perceptions of infographics. Seventy-three percent of students from 361 responses belonged to health-related academic backgrounds. Seventy-two percent felt more likely to share infographics than written articles on social media due to the visual appeal. Nearly 90% felt it was easier to navigate through complicated science and that more scientists should use infographics on social media. Educational background did not influence the perceived usefulness of infographics in understanding scientific information. Infographics are perceived favourably in conveying scientific information about COVID-19 on social media. Findings from this study can inform communication strategies during a pandemic and, more broadly, global crises.
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COVID-19 , Mídias Sociais , COVID-19/epidemiologia , Comunicação , Estudos Transversais , Visualização de Dados , Humanos , Pandemias , Inquéritos e QuestionáriosRESUMO
Slowing light in a non-dispersive and controllable fashion opens the door to many new phenomena in photonics. As such, many schemes have been put forward to decrease the velocity of light, most of which are limited in bandwidth or incur high losses. In this paper we show that a long metallic helix supports a low-loss, broadband slow wave with a mode index that can be controlled via geometrical design. For one particular geometry, we characterise the dispersion of the mode, finding a relatively constant mode index of [Formula: see text] 45 between 10 and 30 GHz. We compare our experimental results to both a geometrical model and full numerical simulation to quantify and understand the limitations in bandwidth. We find that the bandwidth of the region of linear dispersion is associated with the degree of hybridisation between the fields of a helical mode that travels around the helical wire and an axial mode that disperses along the light line. Finally, we discuss approaches to broaden the frequency range of near-constant mode index: we find that placing a straight wire along the axis of the helix suppresses the interaction between the axial and high index modes supported by the helix, leading to both an increase in bandwidth and a more linear dispersion.
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OBJECTIVES: A life-course perspective emphasizes healthy behaviors before, during, and after pregnancy to support a multi-generational risk reduction in obesity for mothers and infants. Optimal timing, content, and dose of such interventions is not well defined. METHODS: We conducted a nested cohort within a randomized trial to evaluate whether a healthy lifestyle intervention around pregnancy led to a "spill-over effect," including a healthier rate (kg/week) of maternal gestational weight gain, and infant growth during the first year. Study enrollment began in 2012, follow-up data collection completed in 2018, and the data were analyzed in 2019. The intervention focused on healthy maternal diet and physical activity but not pregnancy weight or infant feeding. Outcome data were abstracted from electronic medical records. RESULTS: Of the 165 women who became pregnant, 114 enrolled in the nested cohort. The average pre-pregnancy BMI was 29.6 (SD 5.1) kg/m2. Mixed effects models suggested clinically insignificant differences in both the rate of gestational weight gain (-0.02 kg/week; 95% CI -0.09, 0.06) and the rate of infant growth (difference at 1 year: -0.002 kg/cm; 95% CI -0.009, 0.005). CONCLUSIONS FOR PRACTICE: A behavioral intervention that focused on overall maternal health delivered in the time around pregnancy did not result in a "spill-over effect" on healthy gestational weight gain or healthy infant growth during the first year of life. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT01316653.
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Ganho de Peso na Gestação/fisiologia , Crescimento e Desenvolvimento/fisiologia , Complicações na Gravidez/etiologia , Adulto , Estudos de Coortes , Correlação de Dados , Feminino , Humanos , Lactente , Recém-Nascido/crescimento & desenvolvimento , Sobrepeso/complicações , Sobrepeso/etiologia , Gravidez , Complicações na Gravidez/epidemiologiaRESUMO
Weyl points are the crossings of linearly dispersing energy bands of three-dimensional crystals, providing the opportunity to explore a variety of intriguing phenomena such as topologically protected surface states and chiral anomalies. However, the lack of an ideal Weyl system in which the Weyl points all exist at the same energy and are separated from any other bands poses a serious limitation to the further development of Weyl physics and potential applications. By experimentally characterizing a microwave photonic crystal of saddle-shaped metallic coils, we observed ideal Weyl points that are related to each other through symmetry operations. Topological surface states exhibiting helicoidal structure have also been demonstrated. Our system provides a photonic platform for exploring ideal Weyl systems and developing possible topological devices.
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Pain, pruritus, and nausea are complex sensory and emotional physiological symptoms that can vary widely between people and even within an individual, depending on the context and meaning of the symptom and the psychological state of the person. This article reviews the acute neural transmission of pain, pruritus, and nausea symptoms, which can begin in the periphery and/or viscera. The subsequent multiple pathways in the central nervous system that become involved in the processing of these symptoms are also discussed. The authors describe human brain imaging studies that have revealed consistent cortical and subcortical networks activated by these symptoms, including sensory, limbic, and associative regions. In particular, the authors discuss information revealed by the studies regarding the primary somatosensory cortex, secondary somatosensory cortex, anterior cingulate cortex, insula, prefrontal cortex and thalamus, are the brain areas most commonly activated by noxious stimuli. Finally, the authors describe treatment options for chronic presentations of these symptoms, which are, in part, based on central nervous processing of these sensations.
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The discovery of topological phases has introduced new perspectives and platforms for various interesting physics originally investigated in quantum contexts and then, on an equal footing, in classic wave systems. As a characteristic feature, nontrivial Fermi arcs, connecting between topologically distinct Fermi surfaces, play vital roles in the classification of Dirac and Weyl semimetals, and have been observed in quantum materials very recently. However, in classical systems, no direct experimental observation of Fermi arcs in momentum space has been reported so far. Here, using near-field scanning measurements, we show the observation of photonic topological surface-state arcs connecting topologically distinct bulk states in a chiral hyperbolic metamaterial. To verify the topological nature of this system, we further observe backscattering-immune propagation of a nontrivial surface wave across a three-dimension physical step. Our results demonstrate a metamaterial approach towards topological photonics and offer a deeper understanding of topological phases in three-dimensional classical systems.Topological effects known from condensed matter physics have recently also been explored in photonic systems. Here, the authors directly observe topological surface-state arcs in momentum space by near-field scanning the surface of a chiral hyperbolic metamaterial.
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We present an experimental and computational study of the response of twisted-cross metamaterials that provide near dispersionless optical rotation across a broad band of frequencies from 19 GHz to 37 GHz. We compare two distinct geometries: firstly, a bilayer structure comprised of arrays of metallic crosses where the crosses in the second layer are twisted about the layer normal; and secondly where the second layer is replaced by the complementary to the original, i.e. an array of cross-shaped holes. Through numerical modelling we determine the origin of rotatory effects in these two structures. In both, pure optical rotation occurs in a frequency band between two transmission minima, where alignment of electric and magnetic dipole moments occurs. In the cross/cross metamaterial, the transmission minima occur at the symmetric and antisymmetric resonances of the coupled crosses. By contrast, in the cross/complementary-cross structure the transmission minima are associated with the dipole and quadrupole modes of the cross, the frequencies of which appear intrinsic to the cross layer alone. Hence the bandwidth of optical rotation is found to be relatively independent of layer separation.
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The mesencephalic and metencephalic region (MMR) of the vertebrate central nervous system develops in response to signals produced by the isthmic organizer (IsO). We have previously reported that the LIM homeobox transcription factor Lmx1b is expressed within the chick IsO, where it is sufficient to maintain expression of the secreted factor wnt1. In this paper, we show that zebrafish express two Lmx1b orthologs, lmx1b.1 and lmx1b.2, in the rostral IsO, and demonstrate that these genes are necessary for key aspects of MMR development. Simultaneous knockdown of Lmx1b.1 and Lmx1b.2 using morpholino antisense oligos results in a loss of wnt1, wnt3a, wnt10b, pax8 and fgf8 expression at the IsO, leading ultimately to programmed cell death and the loss of the isthmic constriction and cerebellum. Single morpholino knockdown of either Lmx1b.1 or Lmx1b.2 has no discernible effect on MMR development. Maintenance of lmx1b.1 and lmx1b.2 expression at the isthmus requires the function of no isthmus/pax2.1, as well as Fgf signaling. Transient misexpression of Lmx1b.1 or Lmx1b.2 during early MMR development induces ectopic wnt1 and fgf8 expression in the MMR, as well as throughout much of the embryo. We propose that Lmx1b.1- and Lmx1b.2-mediated regulation of wnt1, wnt3a, wnt10b, pax8 and fgf8 maintains cell survival in the isthmocerebellar region.