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We investigate if employers avoid hiring workers living in neighborhoods with low socioeconomic status and/or with long commuting times. In a large-scale field experiment in the Swedish labor market, we sent more than 4,000 fictitious resumes, with randomly assigned information about the applicants’ residential locations, to firms with advertised vacancies. Our findings show that commuting time has a negative effect on the likelihood of being contacted by an employer, while the socioeconomic status of a neighborhood does not appear to be important. These results offer guidance for policymakers responsible for reversing segregation patterns.

Little is known about the information parents of children with cancer find when searching for clinical trials information on YouTube. Thus, this study aimed to analyse the content, quality and reliability of YouTube videos focused on clinical trials for paediatric cancer. A descriptive cross-sectional design was used, and YouTube was searched using the phrases ‘clinical trials for children with cancer’ and ‘paediatric cancer clinical trials’. Videos that met inclusion criteria were assessed using the instruments Global Quality Scale and DISCERN. About half of the examined videos were in the GQS excellent-quality group and exhibited a total of 84,804 views. The mean time for videos was 5.7 minutes, they originated from the US or UK, were uploaded after 2016, and had a cancer centre/foundation or children hospital as video source. Half of them were focusing on early experimental trials and had a positive tone. Twenty percent were classified as useful without serious shortcomings, almost 50% as misleading with serious shortcomings, and 30% as inappropriate sources of information. In conclusion, most YouTube videos on paediatric cancer trials are not very informative and fall short of what could ethically be required regarding their facilitation of informed decision-making.

Due to the alarming rise of antibiotic resistance, medically unwarranted use of antibiotics has assumed new moral significance. In this paper, a thematic content analysis of focus group discussions was conducted to explore lay people’s views on the moral challenges posed by antibiotic resistance. The most important finding is that lay people are morally sensitive to the problems entailed by antibiotic resistance. Participants saw the decreasing availability of effective antibiotics as a problem of justice. This involves individual as well as collective moral responsibility. Yet, holding agents responsible for their use of antibiotics involves varying degrees of demandingness. In our discussion, these findings are related to the contemporary ethical debate on antibiotic resistance and two proposals for the preservation of antibiotic effectiveness are compared to and evaluated against participants’ views.

The Narrowband Internet of Things (NB-IoT) is a cellular access technology developed by the Third Generation Partnership Project (3GPP) to provide wide area connectivity for the Internet of Things. Since its introduction in 3GPP Release 13, NB-IoT has in a few years achieved a remarkable market presence and is currently providing coverage in close to 100 networks. To further extend the reach of NB-IoT and to connect the unconnected, 3GPP Release 17 is studying the feasibility of adapting NB-IoT to support non-terrestrial networks (NTNs). In this article, we review the fundamentals of NB-IoT and NTN, and explain how NB-IoT can be adapted to support satellite communication through a minimal set of modifications.

Antibiotic resistance (AR) is a major threat to public health and healthcare worldwide. In this article, we analyse and discuss the claim that taking actions to minimize AR is everyone's responsibility, focusing on individual moral responsibility. This should not be merely interpreted as a function of knowledge of AR and the proper use of antibiotics. Instead, we suggest a circumstantial account of individual responsibility for AR, where individuals do or do not engage in judicious antibiotic behaviour with different degrees of voluntariness. Furthermore, we suggest a notion of responsibility as a virtue, in which individuals have the opportunity to develop a sensitivity towards the AR theme and, consequently, are capable of engaging, actively and voluntarily, in judicious antibiotic behaviour. The development of such sensitivity depends on the creation of adequate circumstances, that is individual capacities and availability of resources.

Over three decades of in-situ observations illustrate that the Kelvin–Helmholtz (KH) instability driven by the sheared flow between the magnetosheath and magnetospheric plasma often occurs on the magnetopause of Earth and other planets under various interplanetary magnetic field (IMF) conditions. It has been well demonstrated that the KH instability plays an important role for energy, momentum, and mass transport during the solar-wind-magnetosphere coupling process. Particularly, the KH instability is an important mechanism to trigger secondary small scale (i.e., often kinetic-scale) physical processes, such as magnetic reconnection, kinetic Alfvén waves, ion-acoustic waves, and turbulence, providing the bridge for the coupling of cross scale physical processes. From the simulation perspective, to fully investigate the role of the KH instability on the cross-scale process requires a numerical modeling that can describe the physical scales from a few Earth radii to a few ion (even electron) inertial lengths in three dimensions, which is often computationally expensive. Thus, different simulation methods are required to explore physical processes on different length scales, and cross validate the physical processes which occur on the overlapping length scales. Test particle simulation provides such a bridge to connect the MHD scale to the kinetic scale. This study applies different test particle approaches and cross validates the different results against one another to investigate the behavior of different ion species (i.e., H+ and O+), which include particle distributions, mixing and heating. It shows that the ion transport rate is about 1025 particles/s, and mixing diffusion coefficient is about 1010 m2 s−1 regardless of the ion species. Magnetic field lines change their topology via the magnetic reconnection process driven by the three-dimensional KH instability, connecting two flux tubes with different temperature, which eventually causes anisotropic temperature in the newly reconnected flux.

The MMS satellites encountered a Kelvin-Helmholtz instability (KHI) period in the early non-linear phase at the post-noon flank magnetopause on 8 Sep 2015. The adjacent magnetosheath was characterized by a pre-dominantly northward Bz > 0 magnetic field with weakly positive in-plane components in a GSM coordinate system. Ion velocity distribution functions indicate at least 17 KH vortex intervals with two typically D-shaped ion beam distributions, commonly associated with reconnection exhausts, that stream in both directions along a mostly northward magnetic field at 350–775 km/s with a median 525 km/s ion beam speed. The counter-streaming ion beams are superposed on a core population of slowly drifting magnetosheath ions with a field-aligned 50–200 km/s speed. Each interval lasted no more than 5.25 s with a median duration of 1.95 s corresponding to in-plane spatial scales 3 < ΔS < 22 di assuming a constant 1 di = 61 km ion inertial scale and a tailward VKH∼258 km/s KH vortex propagation speed along the MMS trajectory. The counter-streaming ions are predominantly observed in the warm KH vortex region between the cold magnetosheath proper and the hot isotropic ion temperature of a low-latitude boundary layer as the MMS constellation traverses a KH vortex. The in-plane spatial scales and the locations of the observed counter-streaming ion beams generally agree with the predictions of twice-reconnected magnetic fields at two mid-latitude reconnection (MLR) regions in a two-fluid three-dimensional numerical simulation previously reported for this KH event. MMS typically recorded a higher phase space density of the fast parallel ion beam that we associate with a tailward reconnection exhaust from the southern MLR (SMLR) and a lower phase space density of the fast anti-parallel ion beam that we associate with a tailward reconnection exhaust from the northern MLR (NMLR) of similar speed. This is either consistent with MMS being closer to the SMLR region than the NMLR region, or that the KHI conditions may have favored reconnection in the SMLR region for the observed in-plane magnetosheath magnetic field as predicted by a two-fluid three-dimensional numerical simulation.

ObjectiveTo systematically map the scholarly literature on predatory conferences and describe the present state of research and the prevalent attitudes about these conferences.MethodsThis scoping review follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four databases were searched (PubMed/Medline, Web of Science, Scopus and ProQuest Social Sciences Premium Collection). In addition, the included studies’ reference lists were scanned for additional papers not found in the searches. Peer-reviewed publications were included irrespective of study design. Letters and commentary were included if they were peer reviewed. Editorials and literature reviews were excluded.ResultsFrom 809 initial publications, 20 papers were included in the review, from 12 countries and covered a wide range of science disciplines, from nursing/medicine to energy/technology and computer science. More than half were empirical and published after 2017. In most papers, a definition of the term predatory conferences was put forward. Spam email invitations with flattering language were the most common characteristics, and the conferences were often hosted by unknown organisations that used copied pictures without permission. High fees, lack of peer review, and a multidisciplinary scope were signal features. All papers explicitly or implicitly suggested possible reasons for participating in predatory conferences. Some reasons were related to the overall context of academic work, the nature of predatory conferences (eg, researchers falling prey to misleading information about a conference or choosing a conference based on an attractive location) and the personal characteristics of researchers. Only one paper reported empirically identified reasons for participating in predatory conferences. The three countermeasures proposed most frequently to deal with predatory conferences were increasing education, emphasising responsibilities of universities and funders, and publishing lists of predatory publishers associated with conferences.ConclusionsThis review identified a scarcity of research concerning predatory conferences. Future empirical as well as fully analytical research should be encouraged by funders, journals and research institutions.

The positron, the antiparticle of the electron, predicted by Dirac in 1931 and discovered by Anderson in 1933, plays a key role in many scientific and everyday endeavours. Notably, the positron is a constituent of antihydrogen, the only long-lived neutral antimatter bound state that can currently be synthesized at low energy, presenting a prominent system for testing fundamental symmetries with high precision. Here, we report on the use of laser cooled Be+ ions to sympathetically cool a large and dense plasma of positrons to directly measured temperatures below 7 K in a Penning trap for antihydrogen synthesis. This will likely herald a significant increase in the amount of antihydrogen available for experimentation, thus facilitating further improvements in studies of fundamental symmetries., Positrons are key to the production of cold antihydrogen. Here the authors report the sympathetic cooling of positrons by interacting them with laser-cooled Be+ ions resulting in a three-fold reduction of the temperature of positrons for antihydrogen synthesis.

We do not know how much clinical physicians carrying out clinical trials in oncology and haematology struggle with ethical concerns. To our knowledge, no empirical research exists on these questions in a Nordic context. Therefore, this study aims to learn what kinds of ethical challenges physicians in Sweden, Denmark and Finland (n = 29) face when caring for patients in clinical trials; and what strategies, if any, they have developed to deal with them. The main findings were that clinical cancer trials pose ethical challenges related to autonomy issues, unreasonable hope for benefits and the therapeutic misconception. Nevertheless, some physicians expressed that struggling with such challenges was not of great concern. This conveys a culture of hope where health care professionals and patients uphold hope and mutually support belief in clinical trials. This culture being implicit, physicians need opportunities to deliberately reflect over the characteristics that should constitute this culture.

The ALPHA collaboration has successfully demonstrated the production and the confinement of cold antihydrogen, $\overline{\mathrm{H}}$. An analysis of trapping data allowed a stringent limit to be placed on the electric charge of the simplest antiatom. Charge neutrality of matter is known to a very high precision, hence a neutrality limit of $\overline{\mathrm{H}}$ provides a test of CPT invariance. The experimental technique is based on the measurement of the deflection of putatively charged $\overline{\mathrm{H}}$ in an electric field. The tendency for trapped $\overline{\mathrm{H}}$ atoms to be displaced by electrostatic fields is measured and compared to the results of a detailed simulation of $\overline{\mathrm{H}}$ dynamics in the trap. An extensive survey of the systematic errors is performed, with particular attention to those due to the silicon vertex detector, which is the device used to determine the $\overline{\mathrm{H}}$ annihilation position. The limit obtained on the charge of the $\overline{\mathrm{H}}$ atom is \mbox{$ Q = (-1.3\pm1.8\pm0.4)\times10^{-8}$}, representing the first precision measurement with $\overline{\mathrm{H}}$., Comment: 5 pages, 3 figures

At the historic Shelter Island Conference on the Foundations of Quantum Mechanics in 1947, Willis Lamb reported an unexpected feature in the fine structure of atomic hydrogen: a separation of the 2S

The photon—the quantum excitation of the electromagnetic field—is massless but carries momentum. A photon can therefore exert a force on an object upon collision1. Slowing the translational motion of atoms and ions by application of such a force2,3, known as laser cooling, was first demonstrated 40 years ago4,5. It revolutionized atomic physics over the following decades6–8, and it is now a workhorse in many fields, including studies on quantum degenerate gases, quantum information, atomic clocks and tests of fundamental physics. However, this technique has not yet been applied to antimatter. Here we demonstrate laser cooling of antihydrogen9, the antimatter atom consisting of an antiproton and a positron. By exciting the 1S–2P transition in antihydrogen with pulsed, narrow-linewidth, Lyman-α laser radiation10,11, we Doppler-cool a sample of magnetically trapped antihydrogen. Although we apply laser cooling in only one dimension, the trap couples the longitudinal and transverse motions of the anti-atoms, leading to cooling in all three dimensions. We observe a reduction in the median transverse energy by more than an order of magnitude—with a substantial fraction of the anti-atoms attaining submicroelectronvolt transverse kinetic energies. We also report the observation of the laser-driven 1S–2S transition in samples of laser-cooled antihydrogen atoms. The observed spectral line is approximately four times narrower than that obtained without laser cooling. The demonstration of laser cooling and its immediate application has far-reaching implications for antimatter studies. A more localized, denser and colder sample of antihydrogen will drastically improve spectroscopic11–13 and gravitational14 studies of antihydrogen in ongoing experiments. Furthermore, the demonstrated ability to manipulate the motion of antimatter atoms by laser light will potentially provide ground-breaking opportunities for future experiments, such as anti-atomic fountains, anti-atom interferometry and the creation of antimatter molecules., The successful laser cooling of trapped antihydrogen, the antimatter atom formed by an antiproton and a positron (anti-electron), is reported.

The 3rd Generation Partnership Project (3GPP) completed the first global fifth-generation (5G) system standard in its Release 15, paving the way for making 5G a commercial reality. So, what is next in 5G system evolution to further expand the 3GPP ecosystem? Enabling 5G system to support satellite communications is one direction under exploration in 3GPP. There has been a resurgence of interest in providing connectivity from space, stimulated by technology advancement and demand for ubiquitous connectivity services. The ongoing evolution of 5G standards provides a unique opportunity to revisit satellite communications. In this chapter, we focus on the 5G radio access network known as the new radio (NR) and study how to adapt the NR air interface for satellite links. We first provide an overview of use cases and a primer on satellite communications. We then identify key technical challenges faced by NR evolution for satellite communications and propose solutions to overcome them.

Background: Predatory publishing poses a fundamental threat to the development of nursing knowledge. Previous research has suggested that authors of papers published in predatory journals are mainly inexperienced researchers from low- and middle-income countries. Less attention has been paid to contributors from high-income countries. Aim: To describe the prevalence and characteristics of Swedish authors publishing in predatory nursing journals. Design: Quantitative descriptive case study. Participants and research context: Descriptive statistics were used to analyse the academic positions and academic affiliations of the authors of 39 papers published in predatory nursing journals during 2018 and 2019. Predatory nursing journals with Swedish contributors were identified by searching public listings of papers and applying a set of criteria. Journal site archives were used to identify additional papers with Swedish authors. Ethical considerations: This study was conducted in accordance with national regulations and ethical principles of research. Results: Almost two-thirds of Swedish authors publishing in predatory nursing journals hold senior academic positions. A small group of higher education institutions account for a majority of academic affiliations. Findings suggest that higher education institutions and experienced nursing researchers from Sweden make substantial contributions to predatory nursing journals, but that predatory publication habits might be concentrated in a limited number of academics and research milieus. A year-to-year comparison indicates that the prevalence of publishing in predatory journals might be diminishing. Discussion: Swedish nurse researchers help legitimize predatory journals, thus jeopardizing the trustworthiness of academic nursing knowledge. Substandard papers in predatory journals may pass as legitimate and be used to further academic careers. Experienced researchers are misleading junior colleagues, as joint publications might become embarrassments and liabilities. Conclusion: While the academic nursing community needs to address the problem of predatory publishing, there is some hope that educational efforts might have an effect on combating predatory publishing in nursing.

We report Magnetospheric Multiscale four-spacecraft observations of a thin reconnecting current sheet with weakly asymmetric inflow conditions and a guide field of approximately twice the reconnecting magnetic field. The event was observed at the interface of interlinked magnetic field lines at the flank magnetopause when the maximum spacecraft separation was 370 km and the spacecraft covered & SIM;1.7 ion inertial lengths (d(i)) in the reconnection outflow direction. The ion-scale spacecraft separation made it possible to observe the transition from electron-only super ion-Alfvenic outflow near the electron diffusion region (EDR) to the emergence of sub-Alfvenic ion outflow in the ion diffusion region (IDR). The EDR to IDR evolution over a distance less than 2 d(i) also shows the transition from a near-linear reconnecting magnetic field reversal to a more bifurcated current sheet as well as significant decreases in the parallel electric field and dissipation. Both the ion and electron heating in this diffusion region event were similar to the previously reported heating in the far downstream exhausts. The dimensionless reconnection rate, obtained four different ways, was in the range of 0.13-0.27. This event reveals the rapid spatial evolution of the plasma and electromagnetic fields through the EDR to IDR transition region.& nbsp;(C) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

Magnetospheric Multiscale (MMS) encountered the primary low-latitude magnetopause reconnection site when the inter-spacecraft separation exceeded the upstream ion inertial length. Classical signatures of the ion diffusion region (IDR), including a sub-ion-Alfv\'enic de-magnetized ion exhaust, a super-ion-Alfv\'enic magnetized electron exhaust, and Hall electromagnetic fields, are identified. The opening angle between the magnetopause and magnetospheric separatrix is $30^\circ\pm5^\circ$. The exhaust preferentially expands sunward, displacing the magnetosheath. Intense pileup of reconnected magnetic flux occurs between the magnetosheath separatrix and the magnetopause in a narrow channel intermediate between the ion and electron scales. The strength of the pileup (normalized values of 0.3-0.5) is consistent with the large angle at which the magnetopause is inclined relative to the overall reconnection coordinates. MMS-4, which was two ion inertial lengths closer to the X-line than the other three spacecraft, observed intense electron-dominated currents and kinetic-to-electromagnetic-field energy conversion within the pileup. MMS-1, 2, and 3 did not observe the intense currents nor the particle-to-field energy conversion but did observe the pileup, indicating that the edge of the generation region was contained within the tetrahedron. Comparisons with particle-in-cell simulations reveal that the electron currents and large inclination angle of the magnetopause are interconnected features of the asymmetric Hall effect. Between the separatrix and the magnetopause, high-density inflowing magnetosheath electrons brake and turn into the outflow direction, imparting energy to the normal magnetic field and generating the pileup. The findings indicate that electron dynamics are likely an important influence on the magnetic field structure within the ion diffusion region., Comment: Submitted to the Journal of Geophysical Research: Space Physics

Internal combustion engine downsizing and powertrain electrification trends in recent years have led to higher thermal loads on the cylinder head materials with an increased number of engine start&ndash, stop thermal load cycles. This requires designing cylinder heads that are resilient against thermomechanical fatigue damage. To reduce the developmental costs, reliable numerical models for use in computer-aided design approaches are required. Thus, a comprehensive understanding of the material deformation behaviour under loads mimicking in-service conditions is desired to make better engineering decisions. This study examines the effect of strain rate on the cyclic deformation behaviour of the A356-T7 + 0.5% Cu aluminium alloy commonly used in modern internal combustion engine cylinder heads. Samples extracted from the valve bridge areas of the cylinder heads are tested in strain-controlled fatigue tests. Samples are tested at strain rates of 1% s&minus, 1 and 10% s&minus, 1 at room temperature, 150 and 200 &deg, C. The material exhibits increased isotropic hardening and softening rates and an increased number of cycles to failure at 10% s&minus, 1. The strain rate has a dramatic influence on the mean stress development at room temperature. The role of silicon particles in the fracture mechanism is investigated using electron microscopy techniques.

The electrification of automotive powertrains in recent years has been driving the development of internal combustion engines towards reduced volumes with higher power outputs. These changes place extreme demands on engine materials. Engineers employ the computer-aided engineering approach to design reliable and cost-effective engines. However, this approach relies on accurate knowledge of the material deformation and fatigue characteristics during service-like loading. The present study seeks to investigate the effect of dwell times on the deformation and fatigue behaviour of the A356-T7 + 0.5 wt.% Cu alloy used to cast cylinder heads. In particular, we study the effect of dwell time duration at various temperatures. A combined fatigue-dwell testing procedure, with the dwell at the maximum compressive strain, replicates the service conditions. It is found that the material exhibits a stress relaxation behaviour with a decreasing relaxation rate. At lower temperatures, the load level influences the relaxation more than at elevated temperatures. However, the dwell does not significantly affect the hardening behaviour or the life of the tested alloy. Finally, we model the time-dependent material behaviour numerically. The Chaboche model, combined with a Cowper&ndash, Symonds power-law, is found to capture the visco-plastic deformation behaviour accurately.

International audience; We investigate both large‐ and small‐scale properties of a Kelvin‐Helmholtz (KH) event at the dusk flank magnetopause using Magnetospheric Multiscale observations on 8 September 2015. We first use two types of 3‐D simulations (global and local) to demonstrate that Magnetospheric Multiscale is close to the most KH unstable region, and so the occurrence of vortex‐induced reconnection may be expected. Because they produce low‐shear current sheets, KH vortices constitute a perfect laboratory to investigate magnetic reconnection with large guide field and low asymmetry. Recent works suggest that magnetic reconnection may be suppressed when a current sheet combines large guide field and pressure gradient (which induces a diamagnetic drift). We thus perform a statistical analysis of high‐resolution data for the 69 KH‐induced low‐shear magnetic reconnection events observed on that day. We find that the suppression mechanism is not at work for most of the observed reconnecting current sheets, as predicted, but we also find that almost all nonreconnecting current sheets should be reconnecting according to this model. This confirms the fact that the model provides a necessary but not sufficient condition for reconnection to occur. Finally, based on the same data set, we study the latitudinal distribution of these magnetic reconnection events combined with global magnetospheric modeling. We find that reconnection associated with KH vortices occurs over a significant range of latitudes at the flank magnetopause. It is not confined to the plane where the growth rate is maximum, in agreement with recent 3‐D simulations.

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum1,2. The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now know governs the world at the atomic scale. Since then, studies involving the Lyman-α line—the 1S–2P transition at a wavelength of 121.6 nanometres—have played an important part in physics and astronomy, as one of the most fundamental atomic transitions in the Universe. For example, this transition has long been used by astronomers studying the intergalactic medium and testing cosmological models via the so-called ‘Lyman-α forest’3 of absorption lines at different redshifts. Here we report the observation of the Lyman-α transition in the antihydrogen atom, the antimatter counterpart of hydrogen. Using narrow-line-width, nanosecond-pulsed laser radiation, the 1S–2P transition was excited in magnetically trapped antihydrogen. The transition frequency at a field of 1.033 tesla was determined to be 2,466,051.7 ± 0.12 gigahertz (1σ uncertainty) and agrees with the prediction for hydrogen to a precision of 5 × 10−8. Comparisons of the properties of antihydrogen with those of its well-studied matter equivalent allow precision tests of fundamental symmetries between matter and antimatter. Alongside the ground-state hyperfine4,5 and 1S–2S transitions6,7 recently observed in antihydrogen, the Lyman-α transition will permit laser cooling of antihydrogen8,9, thus providing a cold and dense sample of anti-atoms for precision spectroscopy and gravity measurements10. In addition to the observation of this fundamental transition, this work represents both a decisive technological step towards laser cooling of antihydrogen, and the extension of antimatter spectroscopy to quantum states possessing orbital angular momentum., The observation of the 1S–2P Lyman-α transition in the antihydrogen atom, the antimatter counterpart of hydrogen, is reported.

This paper concerns the responsibility of co-authors in cases of scientific misconduct. Arguments in research integrity guidelines and in the bioethics literature concerning authorship responsibilities are discussed. It is argued that it is unreasonable to claim that for every case where a research paper is found to be fraudulent, each author is morally responsible for all aspects of that paper, or that one particular author has such a responsibility. It is further argued that it is more constructive to specify what task responsibilities come with different roles in a project and describe what kinds of situations or events call for some kind of action, and what the appropriate actions might be.

Differences in job search behaviour and access to high quality informal networks may be an important reason why immigrants fare worse than natives in many European labour markets. In this study, we ...