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Transitioning from quantum computation on physical qubits to quantum computation on encoded, logical qubits can improve the error rate of operations, and will be essential for realizing valuable quantum computational advantages. Using a neutral atom quantum processor with 256 qubits, each an individual Ytterbium atom, we demonstrate the entanglement of 24 logical qubits using the distance-two [[4,2,2]] code, simultaneously detecting errors and correcting for lost qubits. We also implement the Bernstein-Vazirani algorithm with up to 28 logical qubits encoded in the [[4,1,2]] code, showing better-than-physical error rates. We demonstrate fault-tolerant quantum computation in our approach, guided by the proposal of Gottesman (2016), by performing repeated loss correction for both structured and random circuits encoded in the [[4,2,2]] code. Finally, since distance-two codes can correct qubit loss, but not other errors, we show repeated loss and error correction using the distance-three [[9,1,3]] Bacon-Shor code. These results begin to clear a path for achieving scientific quantum advantage with a programmable neutral atom quantum processor., Comment: 17 pages, 16 figures

We investigate the role of hyperfine structure in resonant-dipole interactions between two atoms cotrapped in an optical tweezer. Two-body loss rates from light-assisted collisions (LACs) are measured across the $^{87}$Rb hyperfine spectrum and connected to properties of molecular photoassociation potentials via a semiclassical model. To obtain our results, we introduce an imaging technique that leverages repulsive LACs to detect two atoms in a trap, thereby circumventing parity constraints in tweezers. Our findings offer key insights for exploiting hyperfine structure in laser-induced collisions to control cold atoms and molecules in a broad range of quantum science applications., Comment: 4 pages, 4 figures

Optical metasurfaces of subwavelength pillars have provided new capabilities for the versatile definition of the amplitude, phase, and polarization of light. In this work, we demonstrate that an efficient dielectric metasurface lens can be used to trap and image single neutral atoms with a long working distance from the lens of 3 mm. We characterize the high-numerical-aperture optical tweezers using the trapped atoms and compare with numerical computations of the metasurface lens performance. We predict that future metasurfaces for atom trapping will be able to leverage multiple ongoing developments in metasurface design and enable multifunctional control in complex quantum information experiments with neutral-atoms arrays., Comment: 11 pages, 6 figures, Add polarization multiplexed lens result in Appendix

Fully online and hybrid study programmes have emerged at a rapid rate across higher education. However, the negative experience of some students, instructors and institutions with emergency remote instruction during the COVID-19 pandemic has led to public concerns over the quality of digital study programmes. As a result, public authorities across the OECD have started to reflect on how to embed the quality assurance (QA) of digital education into their existing QA frameworks for higher education. This Working Paper aims to assist policy makers as they seek to adapt their higher education QA systems to digital education by: reviewing the advice and guidance provided by international and regional quality assurance organisations; analysing the standards and indicators for digital higher education developed by QA agencies; identifying trends and best practice from higher education institutions for the quality management of digital study programmes; and discussing how public authorities can support institutions to enhance their internal quality management policies and processes for digital teaching and learning.

A major barrier to medical imaging research and in particular the development of artificial intelligence (AI) is a lack of large databases of medical images which share images with other researchers. Without such databases it is not possible to train generalisable AI algorithms, and large amounts of time and funding is spent collecting smaller datasets at individual research centres. The OPTIMAM image database (OMI-DB) has been developed to overcome these barriers. OMI-DB consists of several relational databases and cloud storage systems, containing mammography images and associated clinical and pathological information. The database contains over 2.5 million images from 173,319 women collected from three UK breast screening centres. This includes 154,832 women with normal breasts, 6909 women with benign findings, 9690 women with screen-detected cancers and 1888 women with interval cancers. Collection is on-going and all women are followed-up and their clinical status updated according to subsequent screening episodes. The availability of prior screening mammograms and interval cancers is a vital resource for AI development. Data from OMI-DB has been shared with over 30 research groups and companies, since 2014. This progressive approach has been possible through sharing agreements between the funder and approved academic and commercial research groups. A research dataset such as the OMI-DB provides a powerful resource for research.

Atomic magnetometry is one of the most sensitive ways to measure magnetic fields. We present a method for converting a naturally scalar atomic magnetometer into a vector magnetometer by exploiting the polarization dependence of hyperfine transitions in rubidium atoms. First, we fully determine the polarization ellipse of an applied microwave field using a self-calibrating method, i.e. a method in which the light-atom interaction provides everything required to know the field in an orthogonal laboratory frame. We then measure the direction of an applied static field using the polarization ellipse as a three-dimensional reference defined by Maxwell's equations. Although demonstrated with trapped atoms, this technique could be applied to atomic vapors, or a variety of atom-like systems., Comment: 5 pages, 3 figures + supplementary 11 pages, 5 figure

We demonstrate the ability to extract a spin-entangled state of two neutral atoms via postselection based on a measurement of their spatial configuration. Typically, entangled states of neutral atoms are engineered via atom-atom interactions. In contrast, in our work we use Hong-Ou-Mandel interference to postselect a spin-singlet state after overlapping two atoms in distinct spin states on an effective beam splitter. We verify the presence of entanglement and determine a bound on the postselected fidelity of a spin-singlet state of $\left(0.62 \pm 0.03\right)$. The experiment has direct analogy to creating polarization entanglement with single photons and hence demonstrates the potential to use protocols developed for photons to create complex quantum states with noninteracting atoms., Comment: 11 pages, 4 figures

Digitally enhanced learning and teaching is widely used across the European Higher Education Area, with general acceptance growing over the years and institutions widely acknowledging the benefits it brings to the student experience. The strategic focus being placed on digitally enhanced learning and teaching has increased, undoubtedly accelerated by the COVID-19 pandemic, and is reflected in many national and European policies, with the renewed Digital Education Action Plan (2021-2027) underlining "the development of a high-performing digital education ecosystem" as a strategic priority. Set against this prerogative and growing strategic interest, this report presents a review of 20 instruments from around the globe designed for self-assessment of digitally enhanced learning and teaching at higher education institutions. It offers a number of insightful observations concerning their use (or non-use) by institutions for promoting both quality enhancement and digital capacity development. It should be of immediate interest to higher education institutions, but also to policy makers, developers of instruments, and generally, to all those who seek information on such instruments. This publication has been developed under the Erasmus+ co-funded DIGI-HE project, led by the EUA and in partnership with four universities, with the aim of supporting higher education institutions to engage in self-review to develop and enhance their strategic approaches to digitalisation. [This report is developed in partnership with Dublin City University (Ireland), Baden-Wuerttemberg Cooperative State University (Germany), Vytautas Magnus University (Lithuania) and the University of Jyväskylä (Finland).]

We present a weak lensing study of the galaxy cluster IDCS J1426.5+3508 at $z=1.75$, which is the highest redshift strong lensing cluster known and the most distant cluster for which a weak lensing analysis has been undertaken. Using F160W, F814W, and F606W observations with the Hubble Space Telescope, we detect tangential shear at $2\sigma$ significance. Fitting a Navarro-Frenk-White mass profile to the shear with a theoretical median mass-concentration relation, we derive a mass $M_{200,\mathrm{crit}}=2.3^{+2.1}_{-1.4}\times10^{14}$ M$_{\odot}$. This mass is consistent with previous mass estimates from the Sunyaev-Zel'dovich (SZ) effect, X-ray, and strong lensing. The cluster lies on the local SZ-weak lensing mass scaling relation observed at low redshift, indicative of minimal evolution in this relation.

We discuss relaxation and aging processes in the one- and two-dimensional $ABC$ models. In these driven diffusive systems of three particle types, biased exchanges in one direction yield a coarsening process characterized in the long time limit by a logarithmic growth of ordered domains that take the form of stripes. From the time-dependent length, derived from the equal-time spatial correlator, and from the mean displacement of individual particles different regimes in the formation and growth of these domains can be identified. Analysis of two-times correlation and response functions reveals dynamical scaling in the asymptotic logarithmic growth regime as well as complicated finite-time and finite-size effects in the early and intermediate time regimes., Comment: 25 pages, 11 figures, accepted for publication in Physical Review E

This paper describes a research-in-progress study on the link between "learner control" and "self-efficacy" of postgraduate students in an online programme at a New Zealand university. Even though students are familiar with computers and Internet usage, learning online may still pose a challenge, especially for inexperienced online learners. By enabling learners to control their own learning, their interactions increase along with their self-efficacy and a sense of belonging to the learning community, all of which contribute to better academic outcomes. However, few studies have looked at the link between "self-efficacy" of online learners and "learner control" in a real online setting. To do so, students in a postgraduate online programme embedded with "learner control" were selected as the sample group. The preliminary findings showed a positive relationship between these two variables, though not as strong as expected. Follow-up research is being undertaken with a larger sample group.

Gene innovation is a key mechanism on the evolution and phenotypic diversity of life forms. There is a need for tools able to study gene innovation across an increasingly large number of genomic sequences to maximally capitalise our understanding of biological systems. Here we present Comparative-Phylostratigraphy, an open-source software suite that enables to time the emergence of new genes across evolutionary time and to correlate patterns of gene emergence with species traits simultaneously across whole genomes from multiple species. Such a comparative strategy is a new powerful tool for starting to dissect the relationship between gene innovation and phenotypic diversity. We describe and showcase our method by analysing recently published ant genomes. This new methodology identified significant bouts of new gene evolution in ant clades, that are associated with shifts in life-history traits. Our method allows easy integration of new genomic data as it becomes available, and thus will be a valuable analytical tool for evolutionary biologists interested in explaining the evolution of diversity of life at the level of the genes., Comment: 28 pages, 4 tables and 3 figures. Includes Supp Material

One problem of wide interest involves estimating expected crossing-times. Several tools have been developed to solve this problem beginning with the works of Wald and the theory of sequential analysis. An extension of his approach is provided by the optional sampling theorem in conjunction with martingale inequalities. Deriving the explicit close form solution for the expected crossing times may be difficult. In this paper, we provide a framework that can be used to estimate expected crossing times of arbitrary stochastic processes. Our key assumption is the knowledge of the average behavior of the supremum of the process. Our results include a universal sharp lower bound on the expected crossing times.

Preservice teachers in special education at Eastern Illinois University take two concurrent courses--one teaching instructional techniques for individuals labeled mildly exceptional and the other a practicum experience in a local rural school. A study examined the preservice teachers' perceptions of what they learned working with special needs students and how they felt about their preparation for the practicum experience. Pre- and post-surveys completed by 36 preservice teachers indicated that the majority of those who completed their practicum at an elementary school felt that they were comfortable teaching math, reading, spelling, and phonics; that they were able to collaborate effectively with their preservice teachers, their cooperating teacher, and their practicum supervisor; and that carrying out an effective behavior management plan would increase their teaching effectiveness. They were divided as to whether giving more leeway to students benefitted them as "new" teachers. Those whose practicum was at a middle school were divided as to whether they felt competent to effectively teach mathematics and reading. The majority felt that they had collaborated effectively with their cooperating teacher, preservice teacher peers, and their practicum supervisor. Among those preservice teachers whose practicum was at a high school, a very small minority felt competent teaching mathematics. A majority felt that they effectively taught spelling and implemented a behavior management plan, and were successful in team-teaching. Five strategies used to incorporate students' life experiences into the curriculum are discussed. (TD)

This study examined the social competency of at-risk kindergarten students as they demonstrated the need to establish social communities in order to increase group motivation and peer learning. The study explores the patterns of behaviors that these children demonstrate in order to form social communities, explores the purpose behind their need to establish such communities, and explores the teacher's agenda as it relates to the agenda of social group formation. Subjects were seven children enrolled in a developmental kindergarten. Classroom academic lessons and social interactions were videotaped. Analysis indicated that at-risk kindergarten students must establish social communities within groups of peers in order to feel secure in an instructional setting. In forming social communities, problems may occur for at-risk students who may be viewed by the teacher as being off-task or noncompliant. It is concluded that formed and sustained communities enable the children to monitor the teacher's behavior in order to receive feedback. Teachers are advised to balance their need for successful lesson completion with their students' need to feel a sense of security. (Contains 20 references.) (JDD)

Fully online and hybrid study programmes have emerged at a rapid rate across higher education. However, the negative experience of some students, instructors and institutions with emergency remote instruction during the COVID-19 pandemic has led to public concerns over the quality of digital study programmes. As a result, public authorities across the OECD have started to reflect on how to embed the quality assurance (QA) of digital education into their existing QA frameworks for higher education. This Working Paper aims to assist policy makers as they seek to adapt their higher education QA systems to digital education by: • Reviewing the advice and guidance provided by international and regional quality assurance organisations; • Analysing the standards and indicators for digital higher education developed by QA agencies; • Identifying trends and best practice from higher education institutions for the quality management of digital study programmes; and • Discussing how public authorities can support institutions to enhance their internal quality management policies and processes for digital teaching and learning. [ABSTRACT FROM AUTHOR]

Goal was to reduce the overall cost of human space flight while maintaining the most demanding standards for safety and mission success. In support of this goal, a project team was chartered to replace 18 legacy Space Shuttle nonconformance processes and systems with one fully integrated system Problem Reporting and Corrective Action (PRACA) processes provide a closed-loop system for the identification, disposition, resolution, closure, and reporting of all Space Shuttle hardware/software problems PRACA processes are integrated throughout the Space Shuttle organizational processes and are critical to assuring a safe and successful program Primary Project Objectives Develop a fully integrated system that provides an automated workflow with electronic signatures Support multiple NASA programs and contracts with a single "system" architecture Define standard processes, implement best practices, and minimize process variations

A new sampler is similar to a common snow blower, but is robust and effective in sample collection. The brush wheels are arranged in a triangle shape, each driven by a brushless DC motor and planetary gearhead embedded in the wheel shaft. Its speed can be varied from 800 - 2,000 rpm, depending on the surface regolith resistance. The sample-collecting flow path, and internal features, are designed based on flow dynamics, and the sample-collecting rates have consistently exceeded the requirement under various conditions that span the range of expected surface properties. The brush-wheel sampler (BWS) is designed so that the flow channel is the main body of the apparatus, and links the brush-wheel assembly to the sample canister. The combination of the three brush wheels, the sample flow path, and the canister location make sample collection, storage, and transfer an easier task.