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Quantum gas microscopes have revolutionized quantum simulations with ultracold atoms, allowing one to measure local observables and snapshots of quantum states. However, measurements so far were mostly carried out in the occupation basis. Here, we demonstrate how all kinetic operators, such as kinetic energy or current operators, can be measured and manipulated with single-bond resolution. Beyond simple expectation values of these observables, the single-shot measurements allow one to access full counting statistics and complex correlation functions. Our work paves the way for the implementation of efficient quantum state tomography and hybrid quantum computing protocols for itinerant particles on a lattice. In addition, we demonstrate how site-resolved programmable potentials enable a spatially selective, parallel readout in different bases as well as the engineering of arbitrary initial states.
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Climate change may be the greatest health threat of the twenty-first century, impacting lives both directly and indirectly, through undermining the environmental and social determinants of health. Rapid action to decarbonize economies and build resilience is justified on health, human rights, environmental and economic grounds. While the necessary health response is wide ranging, it can largely be encapsulated within three grand challenges: (i) promote actions that both reduce carbon emissions and improve health; (ii) build better, more climate-resilient and low-carbon health systems; and (iii) implement public health measures to protect from the range of climate risks to health. The health community can make a unique and powerful contribution, applying its trusted voice to climate leadership and advocacy, providing evidence for action, taking responsibility for climate resilience and decarbonization of healthcare systems, and guiding other sectors whose actions impact substantially on health, carbon emissions and climate resilience.
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Mudança Climática , Saúde Pública , Humanos , Atenção à Saúde , Programas Governamentais , CarbonoRESUMO
From the standard model of particle physics to strongly correlated electrons, various physical settings are formulated in terms of matter coupled to gauge fields. Quantum simulations based on ultracold atoms in optical lattices provide a promising avenue to study these complex systems and unravel the underlying many-body physics. Here, we demonstrate how quantized dynamical gauge fields can be created in mixtures of ultracold atoms in optical lattices, using a combination of coherent lattice modulation with strong interactions. Specifically, we propose implementation of â¤2 lattice gauge theories coupled to matter, reminiscent of theories previously introduced in high-temperature superconductivity. We discuss a range of settings from zero-dimensional toy models to ladders featuring transitions in the gauge sector to extended two-dimensional systems. Mastering lattice gauge theories in optical lattices constitutes a new route toward the realization of strongly correlated systems, with properties dictated by an interplay of dynamical matter and gauge fields.
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Carbapenem-resistant Enterobacteriaceae (CRE) cause health care-associated infections worldwide, and they are of severe concern due to limited treatment options. We report an outbreak of KPC-2-producing CRE that was caused by horizontal transmission of a promiscuous plasmid across different genera of bacteria and hospitals in Germany. Eleven isolates (8 Citrobacter freundii, 2 Klebsiella oxytoca, and 1 Escherichia coli) were obtained from seven critically ill patients during the six months of the outbreak in 2016. One patient developed a CRE infection while the other six patients were CRE-colonized. Three patients died in the course of the hospital stay. Six of the seven patients carried the same C. freundii clone; one K. oxytoca clone was found in two patients, and one patient carried E. coli and C. freundii. Molecular analysis confirmed the presence of a conjugative, bla KPC-2-carrying 70 kb-IncN plasmid in C. freundii and E. coli and an 80 kb-IncN plasmid in K. oxytoca. All transconjugants harbored either the 70 or 80 kb plasmid with bla KPC-2, embedded within transposon variant Tn4401g. Whole genome sequencing and downstream bioinformatics analyses of all plasmid sequences showed an almost perfect match when compared to a bla KPC-2-carrying plasmid of a large outbreak in another German hospital two years earlier. Differences in plasmid sizes and open reading frames point to the presence of inserted mobile genetic elements. There are few outbreak reports worldwide on the transmission of bla KPC-2-carrying plasmids across different bacterial genera. Our data suggest a regional and supraregional spread of bla KPC-2-carrying IncN-plasmids harboring the Tn4401g isoform in Germany.
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The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are therefore robust against perturbations. A prominent example is the two-dimensional (2D) integer quantum Hall effect: it is characterized by the first Chern number, which manifests in the quantized Hall response that is induced by an external electric field. Generalizing the quantum Hall effect to four-dimensional (4D) systems leads to the appearance of an additional quantized Hall response, but one that is nonlinear and described by a 4D topological invariant-the second Chern number. Here we report the observation of a bulk response with intrinsic 4D topology and demonstrate its quantization by measuring the associated second Chern number. By implementing a 2D topological charge pump using ultracold bosonic atoms in an angled optical superlattice, we realize a dynamical version of the 4D integer quantum Hall effect. Using a small cloud of atoms as a local probe, we fully characterize the nonlinear response of the system via in situ imaging and site-resolved band mapping. Our findings pave the way to experimentally probing higher-dimensional quantum Hall systems, in which additional strongly correlated topological phases, exotic collective excitations and boundary phenomena such as isolated Weyl fermions are predicted.
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INTRODUCTION: Only one-third of the European population meets the minimum recommended levels of physical activity (PA). Physical inactivity is a major risk factor for non-communicable diseases. Walking and cycling for transport (active mobility, AM) are well suited to provide regular PA. The European research project Physical Activity through Sustainable Transport Approaches (PASTA) pursues the following aims: (1) to investigate correlates and interrelations of AM, PA, air pollution and crash risk; (2) to evaluate the effectiveness of selected interventions to promote AM; (3) to improve health impact assessment (HIA) of AM; (4) to foster the exchange between the disciplines of public health and transport planning, and between research and practice. METHODS AND ANALYSIS: PASTA pursues a mixed-method and multilevel approach that is consistently applied in seven case study cities. Determinants of AM and the evaluation of measures to increase AM are investigated through a large scale longitudinal survey, with overall 14,000 respondents participating in Antwerp, Barcelona, London, Örebro, Rome, Vienna and Zurich. Contextual factors are systematically gathered in each city. PASTA generates empirical findings to improve HIA for AM, for example, with estimates of crash risks, factors on AM-PA substitution and carbon emissions savings from mode shifts. Findings from PASTA will inform WHO's online Health Economic Assessment Tool on the health benefits from cycling and/or walking. The study's wide scope, the combination of qualitative and quantitative methods and health and transport methods, the innovative survey design, the general and city-specific analyses, and the transdisciplinary composition of the consortium and the wider network of partners promise highly relevant insights for research and practice. ETHICS AND DISSEMINATION: Ethics approval has been obtained by the local ethics committees in the countries where the work is being conducted, and sent to the European Commission before the start of the survey. The PASTA website (http://www.pastaproject.eu) is at the core of all communication and dissemination activities.
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Cidades , Nível de Saúde , Atividade Motora/fisiologia , Meios de Transporte , Poluição do Ar/efeitos adversos , Ciclismo/fisiologia , Meio Ambiente , Europa (Continente) , Humanos , Estudos Longitudinais , Meio Social , População Urbana , Caminhada/fisiologiaRESUMO
BACKGROUND: Developing national physical activity (PA) recommendations is an essential element of an effective national approach to promote PA. METHODS: Systematic overview and analysis of national PA recommendations across the European Region of the World Health Organization (WHO). The WHO European national information focal points provided information which was complemented through online searches and input from other experts. RESULTS: Information received until summer 2012 from 37 countries was analyzed. Sixteen countries did not have national recommendations while 21 countries did. For 17 countries, the source document was accessible. Seventeen recommendations referred to adults, 14 to young people and 6 to older adults. Most national recommendations for children and young people are quite similar: 12 countries recommend at least 60 minutes of moderate- to vigorous-intensity PA each day, in line with the WHO global recommendation. Three countries recommend longer durations and one a lower one. In some countries, slight variations were found regarding the recommended intensity and minimum bouts. Only one country was fully in line with the WHO recommendations. Two countries have issued separate recommendations for pre-school children. For adults, most countries still follow the 1995 United States recommendations of "at least 30 minutes on 5 days a week". Three countries were fully in line with the WHO recommendations. Four countries give specific recommendations on reducing weight, avoiding weight gain or continuing weight maintenance. The six identified national PA recommendations for older adults are mainly similar to those for adults but underline that particularly for this age group also less activity has important health benefits; four countries also recommend balance training. CONCLUSIONS: About half of the countries for which information was available and likely less than 40% of all 53 countries in the WHO European Region have developed national PA recommendations. Further investment is needed to address this important step towards a comprehensive PA promotion approach. Much remains to be done for the 2010 WHO recommendations to be fully reflected in national documents across all parts of the Region and all age groups. In addition, avoiding extended periods of inactivity and overweight are only addressed by a minority of countries yet.
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Comportamentos Relacionados com a Saúde , Diretrizes para o Planejamento em Saúde , Promoção da Saúde/estatística & dados numéricos , Atividade Motora , Sobrepeso/prevenção & controle , Adulto , Etnicidade/estatística & dados numéricos , Europa (Continente)/epidemiologia , Exercício Físico , Guias como Assunto , Humanos , Programas Nacionais de Saúde/organização & administração , Saúde Pública/estatística & dados numéricos , Organização Mundial da SaúdeAssuntos
Antibacterianos/farmacologia , Broncoscopia/efeitos adversos , Carbapenêmicos/farmacologia , Surtos de Doenças , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Pneumonia Bacteriana/epidemiologia , Humanos , Unidades de Terapia Intensiva , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Pneumonia Bacteriana/patologia , Resistência beta-LactâmicaRESUMO
Personal exposure to environmental substances is largely determined by time-microenvironment-activity patterns while moving across locations or microenvironments. Therefore, time-microenvironment-activity data are particularly useful in modeling exposure. We investigated determinants of workday time-microenvironment-activity patterns of the adult urban population in seven European cities. The EXPOLIS study assessed workday time-microenvironment-activity patterns among a total of 1427 subjects (age 19-60 years) in Helsinki (Finland), Athens (Greece), Basel (Switzerland), Grenoble (France), Milan (Italy), Prague (Czech Republic), and Oxford (UK). Subjects completed time-microenvironment-activity diaries during two working days. We present time spent indoors--at home, at work, and elsewhere, and time exposed to tobacco smoke indoors for all cities. The contribution of sociodemographic factors has been assessed using regression models. More than 90% of the variance in indoor time-microenvironment-activity patterns originated from differences between and within subjects rather than between cities. The most common factors that were associated with indoor time-microenvironment-activity patterns, with similar contributions in all cities, were the specific work status, employment status, whether the participants were living alone, and whether the participants had children at home. Gender and season were associated with indoor time-microenvironment-activity patterns as well but the effects were rather heterogeneous across the seven cities. Exposure to second-hand tobacco smoke differed substantially across these cities. The heterogeneity of these factors across cities may reflect city-specific characteristics but selection biases in the sampled local populations may also explain part of the findings. Determinants of time-microenvironment-activity patterns need to be taken into account in exposure assessment, epidemiological analyses, exposure simulations, as well as in the development of preventive strategies that focus on time-microenvironment-activity patterns that ultimately determine exposures.