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The impact of the COVID-19 pandemic resulted in unprecedented labour market disruption, triggering the most severe global labour market crisis on record. The speed and depth of the crisis rendered labour force survey data unable to provide timely information. The ILO nowcasting model was designed to track the disruption in the world of work caused by the pandemic. This required: 1) filling data gaps, 2) increasing the timeliness of available data, and 3) focusing on an indicator that captured well the pandemic disruption: hours worked. The estimates obtained from the ILO nowcasting model have become the backbone of the empirical strategy behind the ILO Monitor on the World of Work publication series. The latest estimates corroborate that the pandemic induced very large declines in hours worked at an unprecedented speed. Furthermore, the recovery process has stalled, driven by a stagnant recovery in developing economies. The country-level input data and estimates of the ILO nowcasting model allow for complementary analysis, which was published in the ILO Monitor. The topics included the effects of COVID-19 testing and tracing, fiscal stimulus, and vaccination on labour market outcomes.

The Hamiltonian limit of lattice gauge theories can be found by extrapolating the results of anisotropic lattice computations, i.e., computations using lattice actions with different temporal and spatial lattice spacings ($a_t\neq a_s$), to the limit of $a_t\to 0$. In this work, we present a study of this Hamiltonian limit for a Euclidean $U(1)$ gauge theory in 2+1 dimensions (QED3), regularized on a toroidal lattice. The limit is found using the renormalized anisotropy $\xi_R=a_t/a_s$, by sending $\xi_R \to 0$ while keeping the spatial lattice spacing constant. We compute $\xi_R$ in $3$ different ways: using both the ``normal'' and the ``sideways'' static quark potential, as well as the gradient flow evolution of gauge fields. The latter approach will be particularly relevant for future investigations of combining quantum computations with classical Monte Carlo computations, which requires the matching of lattice results obtained in the Hamiltonian and Lagrangian formalisms.

Critically ill patients in need of specialized diagnostic or therapeutic procedures, but are being cared for in a hospital without such equipment, have to be transferred to appropriate centers without discontinuation of current critical care (interhospital critical care transfer). These transfers are resource intensive, challenging, and require high logistical effort, which must be managed by a specialized and highly trained team, predeployment planning and efficient crew-resource management strategies. If planned adequately, interhospital critical care transfers can be performed safely without frequent adverse events. Beside routine interhospital critical care transfers, there are special missions (e.g., for patients in quarantine or supported by extracorporeal organ support) that might require adaption of the team composition or standard equipment. This article describes interhospital critical care transport missions including their different phases and special circumstances.Kritisch kranke Patienten, die spezialisierte diagnostische oder therapeutische Verfahren benötigen, jedoch in einem Krankenhaus ohne diesbezügliche Ausstattung versorgt werden, müssen unter Fortführung intensivmedizinischer Maßnahmen zu geeigneten Zentren transportiert werden. Solche Transporte sind herausfordernde Einsätze mit hohem Ressourcenbedarf und logistischem Aufwand, die durch ein spezialisiertes Team bewältigt werden müssen. Hierzu ist neben einem effizienten Crew Resource Management eine gute Planung des Einsatzes notwendig. Bei adäquater Vorbereitung sind solche Einsätze für den Patienten sicher und komplikationsarm durchführbar. Neben Routineintensivtransporten gibt es Sondereinsätze (z. B. isolationspflichtiger Patienten oder Patienten mit extrakorporaler Organunterstützung), die eine Anpassung des Teams oder des vorgehaltenen Materials erfordern. Dieser Beitrag beschreibt die Grundlagen des interhospitalen Intensivtransportes, seine Phasen und Sonderfälle.

39th International Symposium on Lattice Field Theory, Lattice 2022, Bonn, Germany, 8 Aug 2022 - 13 Aug 2022; Proceedings of Science / International School for Advanced Studies (LATTICE2022), 020 (2022)., We propose a variational quantum eigensolver suitable for exploring the phase structure of the multi-flavor Schwinger model in the presence of a chemical potential. The parametric ansatz circuit we design is capable of incorporating the symmetries of the model, present in certain parameter regimes, which allows for reducing the number of variational parameters substantially. Moreover, the ansatz circuit can be implementated on both measurement-based and circuit-based quantum hardware. We numerically demonstrate that our ansatz circuit is able to capture the phase structure of the model and allows for faithfully approximating the ground state. Our results show that our approach is suitable for current intermediate-scale quantum hardware and can be readily implemented on existing quantum devices., Published by SISSA, Trieste

38th International Symposium on Lattice Field Theory, Lattice 2021, Online, United States, 26 Jul 2021 - 30 Jul 2021; Proceedings of Science / International School for Advanced Studies (LATTICE2021), 112 (2022). doi:10.22323/1.396.0112, Quantum and tensor network simulations have emerged as prominent sign-problem free approaches to lattice gauge theories. Unlike conventional Markov chain Monte Carlo methods, they are based on the Hamiltonian formulation. In this talk, we fill a gap in the literature and present the first derivation of the Hamiltonian 3+1D $\theta$-term -- which is an important sign-problem afflicted term -- for Abelian and non-Abelian lattice gauge theories. Furthermore, we perform exact diagonalization for a 3+1D U(1) lattice gauge theory including the $\theta$-term on a unit periodic cube. Our numerical results reveal a novel phase transition at fixed values of $\theta$ in the strong-coupling regime. The transition is evidenced by an avoided level crossing in the ground state energy, as well as sudden changes in the plaquette expectation value, the electric energy density, and the topological charge density. Extensions of our work to larger lattices can be readily performed using state-of-the-art tensor network simulations. Moreover, our work provides a concrete starting point for an eventual quantum simulation of the $\theta$-dependent phase structure and dynamics of lattice gauge theories in 3+1D. This talk is mainly based on [1]. We expand beyond [1] by including a derivation of the (non-)Abelian fixed-length Higgs term in the Hamiltonian formulation for future studies of (non-)Abelian-Higgs models with a $\theta$-term., Published by SISSA, Trieste

39th International Symposium on Lattice Field Theory, Lattice 2022, Bonn, Germany, 8 Aug 2022 - 13 Aug 2022; Proceedings of Science / International School for Advanced Studies (LATTICE2022), 046 (2022). doi:10.22323/1.430.0046, Lattice computations in the Hamiltonian formulation have so far mainly focused on staggered fermions. In these proceedings, we study Wilson fermions in the Hamiltonian formulation and propose a new method to determine the resulting mass shift. As a benchmark study, we examine the one-flavour Schwinger model with Wilson fermions and a topological $\theta$-term using matrix product states. Wilson fermions explicitly break chiral symmetry; thus, the bare mass of the lattice model receives an additive renormalization. In order to measure this mass shift directly, we develop a method that is suitable for the Hamiltonian formulation, which relies on the fact that the vacuum expectation value of the electric field density vanishes when the renormalized mass is zero. We examine the dependence of the mass shift on the lattice spacing, the lattice volume, the $\theta$-parameter, and the Wilson parameter. Using the mass shift, we then perform the continuum extrapolation of the electric field density and compare the resulting mass dependence to the analytical predictions of mass perturbation theory. We demonstrate that incorporating the mass shift significantly improves the continuum extrapolation. Finally, we apply our method to the same model using staggered fermions instead of Wilson fermions and compare the resulting mass shift to recent theoretical predictions., Published by SISSA, Trieste

Quantum technologies offer the prospect to efficiently simulate sign-problem afflicted regimes in lattice field theory, such as the presence of topological terms, chemical potentials, and out-of-equilibrium dynamics. In this work, we derive the $(3+1)\mathrm{D}$ topological $\ensuremath{\theta}$-term for Abelian and non-Abelian lattice gauge theories in the Hamiltonian formulation, paving the way toward Hamiltonian-based simulations of such terms on quantum and classical computers. We further study numerically the zero-temperature phase structure of a $(3+1)\mathrm{D}$ U(1) lattice gauge theory with the $\ensuremath{\theta}$-term via exact diagonalization for a single periodic cube. In the strong coupling regime, our results suggest the occurrence of a phase transition at constant values of $\ensuremath{\theta}$, as indicated by an avoided level crossing and abrupt changes in the plaquette expectation value, the electric energy density, and the topological charge density. These results could in principle be cross-checked by the recently developed $(3+1)\mathrm{D}$ tensor network methods and quantum simulations, once sufficient resources become available.

La expansion de las cadenas mundiales de suministro (CMS) desconecta la ubicacion de los empleos de la demanda correspondiente. Los autores utilizan la base de datos mundial de insumo-producto (WIOD) para examinar estos vinculos en 40 paises en el periodo 1995-2013, ampliar anteriores analisis de la OIT y proporcionar evidencia sobre el empleo creado por cada combinacion ubicacion del empleo-destino de exportacion. Observan un cambio en los patrones de demanda y oferta de empleo en las CMS, un auge de China como generadora de demanda, mayores vinculos de produccion entre las economias emergentes y mas empleos en los servicios sostenidos por las CMS manufactureras.

A partir de estimaciones de la OIT del empleo en las cadenas mundiales de suministro se estudia el impacto de las barreras al comercio de bienes y servicios sobre los empleos nacionales. El analisis empirico confirma las predicciones de un modelo teorico calibrado con datos de la WIOD para 2000 y 2011. Las barreras al comercio de bienes y servicios tienen un impacto transfronterizo sobre los empleos del sector directamente afectado y efectos indirectos sobre otros sectores que aumentan con el tiempo. La creciente interconexion entre paises y sectores en las cadenas mundiales de suministro implica que las politicas comerciales pueden tener importantes efectos sobre los mercados de trabajo de otros paises.

38th International Symposium on Lattice Field Theory, Lattice 2021, Online, United States, 26 Jul 2021 - 30 Jul 2021; Proceedings of Science / International School for Advanced Studies (LATTICE2021), 243 (2022). doi:10.22323/1.396.0243, Readout errors are among the most dominant errors on current noisy intermediate-scale quantum devices. Recently, an efficient and scaleable method for mitigating such errors has been developed, based on classical bit-flip correction. In this talk, we compare the performance of this method for IBM's and Rigetti's quantum devices, demonstrating how the method improves the noisy measurements of observables obtained on the quantum hardware. Moreover, we examine the variance amplification to the data after applying of our mitigation procedure, which is common to all mitigation strategies. We derive a new expression for the variance of the mitigated Pauli operators in terms of the corrected expectation values and the noisy variances. Our hardware results show good agreement with the theoretical prediction, and we demonstrate that the increase of the variance due to the mitigation procedure is only moderate., Published by SISSA, Trieste

The design of parametric quantum circuits (PQCs) for efficient use in variational quantum simulations (VQS) is subject to two competing factors. On one hand, the set of states that can be generated by the PQC has to be large enough to contain the solution state. Otherwise, one may at best find the best approximation of the solution restricted to the states generated by the chosen PQC. On the other hand, the PQC should contain as few parametric quantum gates as possible to minimize noise from the quantum device. Thus, when designing a PQC one needs to ensure that there are no redundant parameters. The dimensional expressivity analysis discussed in these proceedings is a means of addressing these counteracting effects. Its main objective is to identify independent and redundant parameters in the PQC. Using this information, superfluous parameters can be removed and the dimension of the space of states that are generated by the PQC can be computed. Knowing the dimension of the physical state space then allows us to deduce whether or not the PQC can reach all physical states. Furthermore, the dimensional expressivity analysis can be implemented efficiently using a hybrid quantum-classical algorithm. This implementation has relatively small overhead costs both for the classical and quantum part of the algorithm and could therefore be used in the future for on-the-fly circuit construction. This would allow for optimized circuits to be used in every loop of a VQS rather than the same PQC for the entire VQS. These proceedings review and extend work in [1, 2]., Comment: 12 pages, Proceedings of the 38th International Symposium on Lattice Field Theory, 26th-30th July 2021, Zoom/Gather@Massachusetts Institute of Technology

Quantum 5, 422 - (2021). doi:10.22331/q-2021-03-29-422, Parametric quantum circuits play a crucial role in the performance of many variational quantum algorithms. To successfully implement such algorithms, one must design efficient quantum circuits that sufficiently approximate the solution space while maintaining a low parameter count and circuit depth. In this paper, we develop a method to analyze the dimensional expressivity of parametric quantum circuits. Our technique allows for identifying superfluous parameters in the circuit layout and for obtaining a maximally expressive ansatz with a minimum number of parameters. Using a hybrid quantum-classical approach, we show how to efficiently implement the expressivity analysis using quantum hardware, and we provide a proof of principle demonstration of this procedure on IBM's quantum hardware. We also discuss the effect of symmetries and demonstrate how to incorporate or remove symmetries from the parametrized ansatz., Published by Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften, Wien

In Variational Quantum Simulations, the construction of a suitable parametric quantum circuit is subject to two counteracting effects. The number of parameters should be small for the device noise to be manageable, but also large enough for the circuit to be able to represent the solution. Dimensional expressivity analysis can optimize a candidate circuit considering both aspects. In this article, we will first discuss an inductive construction for such candidate circuits. Furthermore, it is sometimes necessary to choose a circuit with fewer parameters than necessary to represent all relevant states. To characterize such circuits, we estimate the best-approximation error using Voronoi diagrams. Moreover, we discuss a hybrid quantum-classical algorithm to estimate the worst-case best-approximation error, its complexity, and its scaling in state space dimensionality. This allows us to identify some obstacles for variational quantum simulations with local optimizers and underparametrized circuits, and we discuss possible remedies., Comment: accepted at 2021 IEEE International Conference on Web Services (ICWS), Special Track: Quantum Software and Services

Physical review / A 105(6), 062404 (2022). doi:10.1103/PhysRevA.105.062404, We develop a classical bit-flip correction method to mitigate measurement errors on quantum computers. This method can be applied to any operator, any number of qubits, and any realistic bit-flip probability. We first demonstrate the successful performance of this method by correcting the noisy measurements of the ground-state energy of the longitudinal Ising model. We then generalize our results to arbitrary operators and test our method both numerically and experimentally on IBM quantum hardware. As a result, our correction method reduces the measurement error on the quantum hardware by up to one order of magnitude. We finally discuss how to preprocess the method and extend it to other error sources beyond measurement errors. For local Hamiltonians, the overhead costs are polynomial in the number of qubits, even if multiqubit correlations are included., Published by Inst., Woodbury, NY

The chapter provides an overview of the labour market challenges posed by a fast ageing global population. It shows that, while the ratio of potential retirees per person participating in the labour market is expected to increase markedly by 2030, the average age of those in the labour force is also set to gradually increase over the same period. These dynamics pose the dual challenge of keeping retirees out of poverty while promoting decent work outcomes for the growing share of older workers in the labour force. The chapter concludes by highlighting a number of policy options to tackle these challenges.

This Chapter investigates the long-term trends in the reallocation of employment across sectors, and assesses their implications for overall working conditions and employment arrangements. Results show that differences in working conditions are sizeable across sectors, so that employment shifts across sectors have the potential to change the quality of employment. However, improvements along this dimension hinge on the assumption that transitioning workers are able to find jobs with better working conditions, which is by no means guaranteed.

This chapter aims to provide a deeper understanding of their underlying drivers of gender gaps. Accordingly, Chapter 2 discusses the descriptive findings from the Gallup–ILO 2017 study and develops a framework for analysing the drivers and mechanisms underlying gender gaps in the labour market. This framework is then applied in a manner to quantify the drivers of lower female labour force participation and is followed by an assessment of gender gaps in the workplace.