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Purpose: To present a novel generalized MR image reconstruction based on pseudoinversion of the encoding matrix (Pinv-Recon) as a simple yet powerful method, and demonstrate its computational feasibility for diverse MR imaging applications. Methods: MR image encoding constitutes a linear mapping of the unknown image to the measured k-space data mediated via an encoding matrix ($ data = Encode \times image$). Pinv-Recon addresses MR image reconstruction as a linear inverse problem ($image = Encode^{-1} \times data$), explicitly calculating the Moore-Penrose pseudoinverse of the encoding matrix using truncated singular value decomposition (tSVD). Using a discretized, algebraic notation, we demonstrate constructing a generalized encoding matrix by stacking relevant encoding mechanisms (e.g., gradient encoding, coil sensitivity encoding, chemical shift inversion) and encoding distortions (e.g., off-center positioning, B$_0$ inhomogeneity, spatiotemporal gradient imperfections, transient relaxation effects). Iterative reconstructions using the explicit generalized encoding matrix, and the computation of the spatial-response-function (SRF) and noise amplification, were demonstrated. Results: We evaluated the computation times and memory requirements (time ~ (size of the encoding matrix)$^{1.4}$). Using the Shepp-Logan phantom, we demonstrated the versatility of the method for various intertwined MR image encoding and distortion mechanisms, achieving better MSE, PSNR and SSIM metrics than conventional methods. A diversity of datasets, including the ISMRM CG-SENSE challenge, were used to validate Pinv-Recon. Conclusion: Although pseudo-inversion of large encoding matrices was once deemed computationally intractable, recent advances make Pinv-Recon feasible. It has great promise for both research and clinical applications, and for educational use., Comment: 26 pages, 8 figures, 2 tables (+ Supplementary Material). Submitted to Magnetic Resonance in Medicine

The SKYSURF project constrained extragalactic background light (EBL) and diffuse light with the vast archive of Hubble Space Telescope (HST) images. Thermal emission from HST itself introduces an additional uncertain background and hinders accurate measurement of the diffuse light level. Here, we use archival WFC3/IR engineering data to investigate and model changes in the temperature of various components in HST's optical path as a function of time (solar cycle) and time of the year (Earth-Sun distance). We also specifically investigate changes in temperature with HST's orbital phase and time since Earth occultation. We investigate possible correlations between HST component temperature and year, and temperature and month. The thermal background changes by less than one Kelvin in the WFC3 pick-off mirror, one of the most important contributors to the thermal background. We model these data to describe the impact that orbital phase, year, and time of year have on the HST and WFC3 component temperatures, and use this to derive the impact on the thermal dark signal and the resulting diffuse light measurements. Based on this improved modeling, we provide new upper limits on the level of diffuse light of 21 nW m-2 sr-1, 32 nW m-2 sr-1, and 25 nW m-2 sr-1 for F125W, F140W, and F160W. Additionally, by accounting for all known sources of measurement uncertainty, we report lower limits on the level of diffuse light of 12 nW m-2 sr-1, 20 nW m-2 sr-1, and 2 nW m-2 sr-1 for F125W, F140W, and F160W., Comment: 18 pages, 12 figures

The means by which the turbulent cascade of energy is dissipated in the solar wind, and in other astrophysical systems, is a major open question. It has recently been proposed that a barrier to the transfer of energy can develop at small scales, which can enable heating through ion-cyclotron resonance, under conditions applicable to regions of the solar wind. Such a scenario fundamentally diverges from the standard picture of turbulence, where the energy cascade proceeds unimpeded until it is dissipated. Here, using data from NASA's Parker Solar Probe, we find that the shape of the magnetic energy spectrum around the ion gyroradius varies with solar wind parameters in a manner consistent with the presence of such a barrier. This allows us to identify critical values of some of the parameters necessary for the barrier to form; we show that the barrier appears fully developed for ion plasma beta of below $\simeq0.5$ and becomes increasingly prominent with imbalance for normalised cross helicity values greater than $\simeq0.4$. As these conditions are frequently met in the solar wind, particularly close to the Sun, our results suggest that the barrier is likely playing a significant role in turbulent dissipation in the solar wind and so is an important mechanism in explaining its heating and acceleration.

We present measurement schemes that do not rely on photon-number resolving detectors, but that are nevertheless optimal for estimating a differential phase shift in interferometry with either an entangled coherent state or a qubit-which-path state (where the path taken by a coherent-state wavepacket is entangled with the state of a qubit). The homodyning schemes analyzed here achieve optimality (saturate the quantum Cram\'er-Rao bound) by maximizing the sensitivity of measurement outcomes to phase-dependent interference fringes in a reduced Wigner distribution. In the presence of photon loss, the schemes become suboptimal, but we find that their performance is independent of the phase to be measured. They can therefore be implemented without any prior information about the phase and without adapting the strategy during measurement, unlike strategies based on photon-number parity measurements or direct photon counting.

Automating enterprise workflows could unlock $4 trillion/year in productivity gains. Despite being of interest to the data management community for decades, the ultimate vision of end-to-end workflow automation has remained elusive. Current solutions rely on process mining and robotic process automation (RPA), in which a bot is hard-coded to follow a set of predefined rules for completing a workflow. Through case studies of a hospital and large B2B enterprise, we find that the adoption of RPA has been inhibited by high set-up costs (12-18 months), unreliable execution (60% initial accuracy), and burdensome maintenance (requiring multiple FTEs). Multimodal foundation models (FMs) such as GPT-4 offer a promising new approach for end-to-end workflow automation given their generalized reasoning and planning abilities. To study these capabilities we propose ECLAIR, a system to automate enterprise workflows with minimal human supervision. We conduct initial experiments showing that multimodal FMs can address the limitations of traditional RPA with (1) near-human-level understanding of workflows (93% accuracy on a workflow understanding task) and (2) instant set-up with minimal technical barrier (based solely on a natural language description of a workflow, ECLAIR achieves end-to-end completion rates of 40%). We identify human-AI collaboration, validation, and self-improvement as open challenges, and suggest ways they can be solved with data management techniques. Code is available at: https://github.com/HazyResearch/eclair-agents

Deep Learning (DL) models excel in computer vision tasks but can be susceptible to adversarial examples. This paper introduces Triple-Metric EvoAttack (TM-EVO), an efficient algorithm for evaluating the robustness of object-detection DL models against adversarial attacks. TM-EVO utilizes a multi-metric fitness function to guide an evolutionary search efficiently in creating effective adversarial test inputs with minimal perturbations. We evaluate TM-EVO on widely-used object-detection DL models, DETR and Faster R-CNN, and open-source datasets, COCO and KITTI. Our findings reveal that TM-EVO outperforms the state-of-the-art EvoAttack baseline, leading to adversarial tests with less noise while maintaining efficiency.

The surfaces of many white dwarfs are polluted by metals, implying a recent accretion event. The tidal disruption of planetesimals is a viable source of white dwarf pollution and offers a unique window into the composition of exoplanet systems. The question of how planetary material enters the tidal disruption radius of the white dwarf is currently unresolved. Using a series of $N$-body simulations, we explore the response of the surrounding planetesimal debris disk as the white dwarf receives a natal kick caused by anisotropic mass loss on the asymptotic giant branch. We find that the kick can form an apse-aligned, eccentric debris disk in the range 30 to 240 AU which corresponds to the orbits of Neptune, the Kuiper Belt, and the scattered disk in our solar system. In addition, many planetesimals beyond 240 AU flip to counter-rotating orbits. Assuming an isotropic distribution of kicks, we predict that approximately 80% of white dwarf debris disks should exhibit significant apsidal alignment and fraction of counter-rotating orbits. The eccentric disk is able to efficiently and continuously torque planetesimals onto radial, star-grazing orbits. We show that the kick causes both an initial burst in tidal disruption events as well as an extended period of 100 Myr where tidal disruption rates are consistent with observed mass accretion rates on polluted white dwarfs., Comment: 11 pages, 5 figures, accepted to ApJL

Radio astronomy file formats are now required to store wide frequency bandwidths and multiple simultaneous receiver beams and must be able to account for versatile observing modes and numerous calibration strategies. The need to capture and archive high-time and high frequency-resolution data, along with the comprehensive metadata that fully describe the data, implies that a new data format and new processing software are required. This requirement is suited to a well-defined, hierarchically-structured and flexible file format. In this paper we present the Spectral-Domain Hierarchical Data Format (`SDHDF') -- a new file format for radio astronomy data, in particular for single dish or beam-formed data streams. Since 2018, SDHDF has been the primary format for data products from the spectral-line and continuum observing modes at Murriyang, the CSIRO Parkes 64-m radio telescope, and we demonstrate that this data format can also be used to store observations of pulsars and fast radio bursts., Comment: Supplementary material (SDHDF definition): https://ars.els-cdn.com/content/image/1-s2.0-S2213133724000192-mmc1.pdf

Long range, multi-qubit parity checks have applications in both quantum error correction and measurement-based entanglement generation. Such parity checks could be performed using qubit-state-dependent phase shifts on propagating pulses of light described by coherent states $\vert\alpha\rangle$ of the electromagnetic field. We consider "flying-cat" parity checks based on an entangling operation that is quantum non-demolition (QND) for Schr\"odinger's cat states $\vert\alpha\rangle\pm \vert-\alpha\rangle$. This operation encodes parity information in the phase of maximally distinguishable coherent states $\vert\pm \alpha\rangle$, which can be read out using a phase-sensitive measurement of the electromagnetic field. In contrast to many implementations, where single-qubit errors and measurement errors can be treated as independent, photon loss during flying-cat parity checks introduces errors on physical qubits at a rate that is anti-correlated with the probability for measurement errors. We analyze this trade-off for three-qubit parity checks, which are a requirement for universal fault-tolerant quantum computing with the subsystem surface code. We further show how a six-qubit entangled "tetrahedron" state can be prepared using these three-qubit parity checks. The tetrahedron state can be used as a resource for controlled quantum teleportation of a two-qubit state, or as a source of shared randomness with potential applications in three-party quantum key distribution. Finally, we provide conditions for performing high-quality flying-cat parity checks in a state-of-the-art circuit QED architecture, accounting for qubit decoherence, internal cavity losses, and finite-duration pulses, in addition to transmission losses., Comment: V2: Section added on implementing flying-cat parity checks with transmon qubits. Version published in Phys. Rev. Research

We investigate the relation between turbulence and magnetic field switchbacks in the inner heliosphere below 0.5 AU in a distance and scale dependent manner. The analysis is performed by studying the evolution of the magnetic field vector increments and the corresponding rotation distributions, which contain the switchbacks. We find that the rotation distributions evolve in a scale dependent fashion, having the same shape at small scales independent of the radial distance, contrary to at larger scales where the shape evolves with distance. The increments are shown to evolve towards a log-normal shape with increasing radial distance, even though the log-normal fit works quite well at all distances especially at small scales. The rotation distributions are shown to evolve towards the Zhdankin et al. (2012) rotation model moving away from the Sun. The magnetic switchbacks do not appear at any distance as a clear separate population. Our results suggest a scenario in which the evolution of the rotation distributions, including switchbacks, is primarily the result of the expansion driven growth of the fluctuations, which are reshaped into a log-normal distribution by the solar wind turbulence.

Due to the complex interactions between rare-earth elements and transition metals, as well as between themselves, rare-earth transition-metal oxides are likely to exhibit highly intriguing and novel magnetic structures and dynamic behaviours. Rare-earth elements in these compounds frequently demonstrate unusual behaviours in their crystal-field (CF) excitations, which necessitate thorough studies for in-depth comprehensions. When cooling from 10 K to 1.5 K through the magnetic ordering temperature of $Er^{3+}$ at 4.1 K, we observed a significant energy shift of the low-lying CF excitation of $Er^{3+}$ in erbium orthoferrite ($ErFeO_3$) from 0.32 meV to 0.75 meV utilizing the inelastic neutron-scattering technique. A sound CF model was proposed for $Er^{3+}$ in $ErFeO_3$ by fitting to the observed CF excitation peaks, which enables to explain all the observed experimental results in a very consistent manner. According to the model, the ground crystal field level of $Er^{3+}$, which corresponds to the lowest Kramers doublet supposed to be at zero energy transfer, has been shifted by the internal magnetic fields induced by both $Er^{3+}$ and $Fe^{3+}$ spin orders below and above the $Er^{3+}$ ordering temperature, respectively. Additional measurements in various magnetic fields offer compelling evidence in favour of this hypothesis. The measured external field dependence of the CF excitation energy led to a derivation of the internal field of $Er^{3+}$ as 0.54 T, which is strongly corroborated by theoretical modelling. Additionally, the g-factor for the $Er^{3+}$ ground state in $ErFeO_3$ shows an exceptionally significant anisotropy., Comment: arXiv admin note: This version has been removed by arXiv administrators as the submitter did not have the right to agree to the license at the time of submission

It is well established that parenting influences child behavior at home, but less is known about the associations between parenting and teacher reports of child behavior at school, an environment more distal from the home context. This study investigated the presence of authoritarian, authoritative, permissive, and uninvolved parenting styles (PS) in a community sample of 321 parents with kindergarteners (M[subscript age]=5.45 years) in the Northwestern United States. This study analyzed (1) which PS were present, (2) if PS was associated with family characteristics, (3) if teacher reported behavior problems in spring of children's kindergarten year varied by PS, and (4) whether associations between PS and child behaviors were moderated by parenting stress. Study hypotheses were that PS would be associated with family characteristics, that teacher reported child behaviors would differ by PS, and that parenting stress would moderate the relationship between PS and behavior problems at school. Results indicated all PS were present. Chi-squares and ANOVA's identified that PS were significantly associated with parenting stress and child problem behaviors. ANOVAs determined differences in parenting stress and problem behaviors depending on PS. ANOVAs revealed parenting stress moderated the relation between PS and child problem behavior. Few studies to date have analyzed the presence of all four PS among kindergarteners and the relationship this has with teacher-reported classroom behavioral concerns. This study sought to fill this gap as results have implications for targeted parenting prevention interventions to promote children's social and behavioral adjustment during the transition to elementary school. [This paper was published in "Journal of Child and Family Studies."]

Recent advances in attention-free sequence models rely on convolutions as alternatives to the attention operator at the core of Transformers. In particular, long convolution sequence models have achieved state-of-the-art performance in many domains, but incur a significant cost during auto-regressive inference workloads -- naively requiring a full pass (or caching of activations) over the input sequence for each generated token -- similarly to attention-based models. In this paper, we seek to enable $\mathcal O(1)$ compute and memory cost per token in any pre-trained long convolution architecture to reduce memory footprint and increase throughput during generation. Concretely, our methods consist in extracting low-dimensional linear state-space models from each convolution layer, building upon rational interpolation and model-order reduction techniques. We further introduce architectural improvements to convolution-based layers such as Hyena: by weight-tying the filters across channels into heads, we achieve higher pre-training quality and reduce the number of filters to be distilled. The resulting model achieves 10x higher throughput than Transformers and 1.5x higher than Hyena at 1.3B parameters, without any loss in quality after distillation.

We consider some integral-geometric quantities that have recently arisen in harmonic analysis and elsewhere, derive some sharp geometric inequalities relating them, and place them in a wider context.

We report measurements of H I content in 11 nearby, actively star-forming, blue compact dwarf galaxies (BCDs) from 21 cm observations with the Arecibo telescope. These BCDs, selected by their red (W2[4.6 $\mu$m]$-$W3[12 $\mu$m]$>$3.8 mag) and bright mid-infrared (MIR) emission (W4[22 $\mu$m]$<$ 7.6 mag), have high specific star formation rates (median sSFR $\sim$10$^{-7.8}$ yr$^{-1}$), similar to high redshift galaxies. H I emission was detected in six sources. We analyze our new detections in the context of previous H I observations of 218 dwarf irregulars (dIs) and BCDs in the literature. The $M_{\rm HI}$-$M_{\ast}$ relation resulting from our observations confirms the dominating fraction of H I gas among baryons in galaxies with lower stellar masses. This Arecibo BCD sample has significantly lower median H I depletion timescales ($\tau_{\rm HI}\sim$ 0.3 Gyr) than other dIs/BCDs ($\sim$ 6.3 Gyr) in the literature. The majority of the sources (10/11) in the Arecibo sample are very red in W1[3.4 $\mu$m]$-$W2[4.6 $\mu$m] colour ($>$ 0.8 mag) implying the presence of warm dust. We investigate the relation of $\tau_{\rm HI}$ with stellar mass ($M_{\ast}$) and sSFR. We find that $\tau_{\rm HI}$ is significantly anti-correlated with $M_{\ast}$ for higher sSFR ($>$10$^{-8.5}$ yr$^{-1}$) and with sSFR for higher stellar mass ($>10^{7.5}\,{\rm M}_{\odot}$) dwarf galaxies. The high sSFR for the BCDs in the Arecibo observed sample is mainly due to their high atomic gas star formation efficiency (SFE) or low $\tau_{\rm HI}$. The low $\tau_{\rm HI}$ or high SFE in these sources is possibly due to runaway star formation in compact and dense super star clusters., Comment: 17(12+5) pages, 7(6+1)figures, 6(4+2) tables, accepted for publication in MNRAS

A wealth of observations have long suggested that the vast majority of isolated classical dwarf galaxies ($M_*=10^7$-$10^9$ M$_\odot$) are currently star-forming. However, recent observations of the large abundance of "Ultra-Diffuse Galaxies" beyond the reach of previous large spectroscopic surveys suggest that our understanding of the dwarf galaxy population may be incomplete. Here we report the serendipitous discovery of an isolated quiescent dwarf galaxy in the nearby Universe, which was imaged as part of the PEARLS GTO program. Remarkably, individual red-giant branch stars are visible in this near-IR imaging, suggesting a distance of $30\pm4$ Mpc, and a wealth of archival photometry point to an sSFR of $2\times10^{-11}$ yr$^{-1}$ and SFR of $4\times10^{-4}$ M$_\odot$ yr$^{-1}$. Spectra obtained with the Lowell Discovery Telescope find a recessional velocity consistent with the Hubble Flow and ${>}1500$ km/s separated from the nearest massive galaxy in SDSS, suggesting that this galaxy was either quenched from internal mechanisms or had a very high-velocity ($>1000$ km/s) interaction with a nearby massive galaxy in the past. This analysis highlights the possibility that many nearby quiescent dwarf galaxies are waiting to be discovered and that JWST has the potential to resolve them., Comment: Accepted to ApJ Letters