557 research outputs found

    A new approach to study gait impairments in Parkinson’s disease based on mixed reality

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    Dissertação de mestrado integrado em Engenharia Biomédica (especialização em Eletrónica Médica)Parkinson’s disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. PD onset is at 55 years-old on average, and its incidence increases with age. This disease results from dopamine-producing neurons degeneration in the basal ganglia and is characterized by various motor symptoms such as freezing of gait, bradykinesia, hypokinesia, akinesia, and rigidity, which negatively impact patients’ quality of life. To monitor and improve these PD-related gait disabilities, several technology-based methods have emerged in the last decades. However, these solutions still require more customization to patients’ daily living tasks in order to provide more objective, reliable, and long-term data about patients’ motor conditions in home-related contexts. Providing this quantitative data to physicians will ensure more personalized and better treatments. Also, motor rehabilitation sessions fostered by assistance devices require the inclusion of quotidian tasks to train patients for their daily motor challenges. One of the most promising technology-based methods is virtual, augmented, and mixed reality (VR/AR/MR), which immerse patients in virtual environments and provide sensory stimuli (cues) to assist with these disabilities. However, further research is needed to improve and conceptualize efficient and patient-centred VR/AR/MR approaches and increase their clinical evidence. Bearing this in mind, the main goal of this dissertation was to design, develop, test, and validate virtual environments to assess and train PD-related gait impairments using mixed reality smart glasses, integrated with another high-technological motion tracking device. Using specific virtual environments that trigger PD-related gait impairments (turning, doorways, and narrow spaces), it is hypothesized that patients can be assessed and trained in their daily challenges related to walking. Also, this tool integrates on-demand visual cues to provide visual biofeedback and foster motor training. This solution was validated with end-users to test the identified hypothesis. The results showed that, in fact, mixed reality has the potential to recreate real-life environments that often provoke PD-related gait disabilities, by placing virtual objects on top of the real world. On the contrary, biofeedback strategies did not significantly improve the patients’ motor performance. The user experience evaluation showed that participants enjoyed participating in the activity and felt that this tool can help their motor performance.A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais comum depois da doença de Alzheimer. O início da DP ocorre, em média, aos 55 anos de idade, e a sua incidência aumenta com a idade. Esta doença resulta da degeneração dos neurónios produtores de dopamina nos gânglios basais e é caracterizada por vários sintomas motores como o congelamento da marcha, bradicinesia, hipocinesia, acinesia, e rigidez, que afetam negativamente a qualidade de vida dos pacientes. Nas últimas décadas surgiram métodos tecnológicos para monitorizar e treinar estas desabilidades da marcha. No entanto, estas soluções ainda requerem uma maior personalização relativamente às tarefas diárias dos pacientes, a fim de fornecer dados mais objetivos, fiáveis e de longo prazo sobre o seu desempenho motor em contextos do dia-a-dia. Através do fornecimento destes dados quantitativos aos médicos, serão assegurados tratamentos mais personalizados. Além disso, as sessões de reabilitação motora, promovidas por dispositivos de assistência, requerem a inclusão de tarefas quotidianas para treinar os pacientes para os seus desafios diários. Um dos métodos tecnológicos mais promissores é a realidade virtual, aumentada e mista (RV/RA/RM), que imergem os pacientes em ambientes virtuais e fornecem estímulos sensoriais para ajudar nestas desabilidades. Contudo, é necessária mais investigação para melhorar e conceptualizar abordagens RV/RA/RM eficientes e centradas no paciente e ainda aumentar as suas evidências clínicas. Tendo isto em mente, o principal objetivo desta dissertação foi conceber, desenvolver, testar e validar ambientes virtuais para avaliar e treinar as incapacidades de marcha relacionadas com a DP usando óculos inteligentes de realidade mista, integrados com outro dispositivo de rastreio de movimento. Utilizando ambientes virtuais específicos que desencadeiam desabilidades da marcha (rodar, portas e espaços estreitos), é possível testar hipóteses de que os pacientes possam ser avaliados e treinados nos seus desafios diários. Além disso, esta ferramenta integra pistas visuais para fornecer biofeedback visual e fomentar a reabilitação motora. Esta solução foi validada com utilizadores finais de forma a testar as hipóteses identificadas. Os resultados mostraram que, de facto, a realidade mista tem o potencial de recriar ambientes da vida real que muitas vezes provocam deficiências de marcha relacionadas à DP. Pelo contrário, as estratégias de biofeedback não provocaram melhorias significativas no desempenho motor dos pacientes. A avaliação feita pelos pacientes mostrou que estes gostaram de participar nos testes e sentiram que esta ferramenta pode auxiliar no seu desempenho motor

    Famílies botàniques de plantes medicinals

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    Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia, Assignatura: Botànica Farmacèutica, Curs: 2013-2014, Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són els recull de 175 treballs d’una família botànica d’interès medicinal realitzats de manera individual. Els treballs han estat realitzat per la totalitat dels estudiants dels grups M-2 i M-3 de l’assignatura Botànica Farmacèutica durant els mesos d’abril i maig del curs 2013-14. Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pel professor de l’assignatura i revisats i finalment co-avaluats entre els propis estudiants. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica

    Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

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    Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

    Repositioning of the global epicentre of non-optimal cholesterol

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    High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

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    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Search for lepton-flavor violating decays of the Higgs boson in the mu tau and e tau final states in proton-proton collisions at root s=13 TeV

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    A search is presented for lepton-flavor violating decays of the Higgs boson to mu t and et. The dataset corresponds to an integrated luminosity of 137 fb(-1) collected at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. No significant excess has been found, and the results are interpreted in terms of upper limits on lepton-flavor violating branching fractions of the Higgs boson. The observed (expected) upper limits on the branching fractions are, respectively, B(H -> mu t) e tau) < 0.22(0.16)% at 95% confidence level.Peer reviewe

    Measurements of Higgs boson production cross sections and couplings in the diphoton decay channel at root s=13 TeV

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    Measurements of Higgs boson production cross sections and couplings in events where the Higgs boson decays into a pair of photons are reported. Events are selected from a sample of proton-proton collisions at root s = 13TeV collected by the CMS detector at the LHC from 2016 to 2018, corresponding to an integrated luminosity of 137 fb(-1). Analysis categories enriched in Higgs boson events produced via gluon fusion, vector boson fusion, vector boson associated production, and production associated with top quarks are constructed. The total Higgs boson signal strength, relative to the standard model (SM) prediction, is measured to be 1.12 +/- 0.09. Other properties of the Higgs boson are measured, including SM signal strength modifiers, production cross sections, and its couplings to other particles. These include the most precise measurements of gluon fusion and vector boson fusion Higgs boson production in several different kinematic regions, the first measurement of Higgs boson production in association with a top quark pair in five regions of the Higgs boson transverse momentum, and an upper limit on the rate of Higgs boson production in association with a single top quark. All results are found to be in agreement with the SM expectations.Peer reviewe

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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    Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at root s=5.02 TeV Using Leptonic Decays

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    The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb(-1). Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as sigma(WW) = 37:0(-5.2)(+5.5) (stat)(-2.6)(+2.7) (syst) pb, sigma(WZ) = 6.4(-2.1)(+2.5) (stat)(-0.3)(+0.5)(syst) pb, and sigma(ZZ) = 5.3(-2.1)(+2.5)(stat)(-0.4)(+0.5) (syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy
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