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Background: Researcher-practitioner partnerships (RPPs) have gained increasing prominence within education, since they are crucial for identifying partners’ problems of practice and seeking solutions for improving district (or school) problems. The CS Pathways RPP project brought together researchers and practitioners, including middle school teachers and administrators from three urban school districts, to build teachers’ capacity to implement an inclusive computer science and digital literacy (CSDL) curriculum for all students in their middle schools. Objective: This study explored the teachers’ self-efficacy development in teaching a middle school CSDL curriculum under the project’s RPP framework. The ultimate goal was to gain insights into how the project’s RPP framework and its professional development (PD) program supported teachers’ self-efficacy development, in particular its challenges and success of the partnership. Method: Teacher participants attended the first-year PD program and were surveyed and/or interviewed about their self-efficacy in teaching CSDL curriculum, spanning topics ranging from digital literacy skills to app creation ability and curriculum implementation. Both survey and interview data were collected and analyzed using mixed methods 1) to examine the reach of the RPP PD program in terms of teachers’ self-efficacy; 2) to produce insightful understandings of the PD program impact on the project’s goal of building teachers’ self-efficacy. Results and Discussion: We reported the teachers’ self-efficacy profiles based on the survey data. A post-survey indicated that a majority of the teachers have high self-efficacy in teaching the CSDL curriculum addressed by the RPP PD program. Our analysis identified five critical benefits the project’s RPP PD program provided, namely collaborative efforts on resource and infrastructure building, content and pedagogical knowledge growth, collaboration and communication, and building teacher identity. All five features have shown direct impacts on teachers' self-efficacy. The study also reported teachers’ perceptions on the challenges they faced and potential areas for improvements. These findings indicate some important features of an effective PD program, informing the primary design of an RPP CS PD program. 

Research-practitioner partnership (RPP) projects using approaches such as design-based implementation research (DBIR), seek to build organizational infrastructure to develop, implement, and sustain educational innovation [19]. Infrastructure consists of the practices and objects that support educational practice. Infrastructure constitutes human and material resources and structures that support joint work [18,29]. Although RPP literature has identified co-design as an infrastructure-building approach, to the best of our knowledge, specific techniques for managing co-design and other infrastructure building practices are still lacking [9,18,23]. Without such tools, RPP partners' varied backgrounds, workplace norms, and priorities can produce behaviors that may be normal in the context of a single organization but can impede communication, resource access, and innovation implementation in a collaborative context. The NSF-funded Computer Science Pathways RPP (CS Pathways) project's DBIR approach uses co-design of a culturally responsive middle school CS curriculum to develop infrastructure for providing high-quality CS education across three urban school districts. The curriculum focuses on developing mobile apps for social good and will be taught by teachers with varied CS experience in varied classroom contexts (e.g., civics, science). The purpose of this workshop paper is to demonstrate a technique, namely Manager Tools One-on-one meetings [15], adapted by CS Pathways partners to manage the co-design process. O3s have six features: they are frequent; scheduled; 15 to 30 minutes in duration; held with all participants working on a specified project; semi-structured; and documented by the manager or researcher. This workshop paper describes how to use O3s to engage teachers and researchers in developing collaborative infrastructure to promote shared exploration of feedback and build and sustain partnerships. 

Identifying features that leak information about sensitive attributes is a key challenge in the design of information obfuscation mechanisms. In this paper, we propose a framework to identify information-leaking features via information density estimation. Here, features whose information densities exceed a pre-defined threshold are deemed information-leaking features. Once these features are identified, we sequentially pass them through a targeted obfuscation mechanism with a provable leakage guarantee in terms of 𝖤𝛾-divergence. The core of this mechanism relies on a data-driven estimate of the trimmed information density for which we propose a novel estimator, named the \textit{trimmed information density estimator} (TIDE). We then use TIDE to implement our mechanism on three real-world datasets. Our approach can be used as a data-driven pipeline for designing obfuscation mechanisms targeting specific features. 

Abstract We present the results of a search for gravitational-wave transients associated with core-collapse supernova SN 2023ixf, which was observed in the galaxy Messier 101 via optical emission on 2023 May 19, during the LIGO–Virgo–KAGRA 15th Engineering Run. We define a five-day on-source window during which an accompanying gravitational-wave signal may have occurred. No gravitational waves have been identified in data when at least two gravitational-wave observatories were operating, which covered ∼14% of this five-day window. We report the search detection efficiency for various possible gravitational-wave emission models. Considering the distance to M101 (6.7 Mpc), we derive constraints on the gravitational-wave emission mechanism of core-collapse supernovae across a broad frequency spectrum, ranging from 50 Hz to 2 kHz, where we assume the gravitational-wave emission occurred when coincident data are available in the on-source window. Considering an ellipsoid model for a rotating proto-neutron star, our search is sensitive to gravitational-wave energy 1 × 10⁻⁴M_⊙c²and luminosity 2.6 × 10⁻⁴M_⊙c²s⁻¹for a source emitting at 82 Hz. These constraints are around an order of magnitude more stringent than those obtained so far with gravitational-wave data. The constraint on the ellipticity of the proto-neutron star that is formed is as low as 1.08, at frequencies above 1200 Hz, surpassing past results. 

Abstract Continuous gravitational waves (CWs) emission from neutron stars carries information about their internal structure and equation of state, and it can provide tests of general relativity. We present a search for CWs from a set of 45 known pulsars in the first part of the fourth LIGO–Virgo–KAGRA observing run, known as O4a. We conducted a targeted search for each pulsar using three independent analysis methods considering single-harmonic and dual-harmonic emission models. We find no evidence of a CW signal in O4a data for both models and set upper limits on the signal amplitude and on the ellipticity, which quantifies the asymmetry in the neutron star mass distribution. For the single-harmonic emission model, 29 targets have the upper limit on the amplitude below the theoretical spin-down limit. The lowest upper limit on the amplitude is 6.4 × 10⁻²⁷for the young energetic pulsar J0537−6910, while the lowest constraint on the ellipticity is 8.8 × 10⁻⁹for the bright nearby millisecond pulsar J0437−4715. Additionally, for a subset of 16 targets, we performed a narrowband search that is more robust regarding the emission model, with no evidence of a signal. We also found no evidence of nonstandard polarizations as predicted by the Brans–Dicke theory. 

Abstract We present results from a search for X-ray/gamma-ray counterparts of gravitational-wave (GW) candidates from the third observing run (O3) of the LIGO–Virgo–KAGRA network using the Swift Burst Alert Telescope (Swift-BAT). The search includes 636 GW candidates received with low latency, 86 of which have been confirmed by the offline analysis and included in the third cumulative Gravitational-Wave Transient Catalogs (GWTC-3). Targeted searches were carried out on the entire GW sample using the maximum-likelihood Non-imaging Transient Reconstruction and Temporal Search pipeline on the BAT data made available via the GUANO infrastructure. We do not detect any significant electromagnetic emission that is temporally and spatially coincident with any of the GW candidates. We report flux upper limits in the 15–350 keV band as a function of sky position for all the catalog candidates. For GW candidates where the Swift-BAT false alarm rate is less than 10⁻³Hz, we compute the GW–BAT joint false alarm rate. Finally, the derived Swift-BAT upper limits are used to infer constraints on the putative electromagnetic emission associated with binary black hole mergers. 

Abstract Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame massM> 70M_⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 <e≤ 0.3 at 16.9 Gpc⁻³yr⁻¹at the 90% confidence level.