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Writing Assignment Tutor Training in STEM (WATTS) is part of a three-year NSF IUSE grant with participants at three institutions. This research project seeks to determine to what extent students in the WATTS project show greater writing improvement than students using writing tutors not trained in WATTS. The team collected baseline, control, and experimental data. Baseline data included reports written by engineering and engineering technology students with no intervention to determine if there were variations in written communication related to student demographics and institutions. Control data included reports written by students who visited tutors with no WATTS training, and experimental data included reports written by students who visited tutors who were WATTS-trained. Reports were evaluated by the research team using a slightly modified version of the American Association of Colleges and Universities (AAC&U) Written Communication VALUE Rubric. Baseline data assessment also provided an opportunity to test the effectiveness of the rubric. This paper presents findings from the analysis of the control and experimental data to determine the impact of WATTS on student writing in lab reports. An aggregate score for each lab report was determined by averaging the reviewer scores. An analysis was run to determine if there was a statistical difference between pre-tutoring lab report scores from the baseline, control, and experimental rubric scores for each criterion and total scores; there was not a statistically significant difference. The research team ran a Wilcoxon signed-rank test to assess the relationship between control and experimental aggregate rubric scores for each criterion. The preliminary analysis of the control and experimental data shows that the WATTS intervention has a positive, statistically significant impact on written communication skills regardless of the campus student demographics. Since WATTS has been shown to be a low-cost, effective intervention to improve engineering and engineering technology students’ written communication skills at these participating campuses, it has potential use for other institutions to positively impact their students’ written communication. 

Undergraduate STEM writing skills, especially in engineering fields, need improvement. Yet students in engineering fields often do not value writing skills and underestimate the amount of writing they will do in their careers. University writing centers can be a helpful resource, but peer writing tutors need to be prepared for the differences between writing for the humanities and writing in STEM fields. The Writing Assignment Tutor Training in STEM (WATTS) model is designed to improve tutor confidence and student writing. In this innovative training, the writing center supervisor collaborates with the STEM instructor to create a one-hour tutor-training where the tutors learn about the assignment content, vocabulary, and expectations. This multidisciplinary collaborative project builds on previous investigative work to determine the impact of WATTS on students, tutors, and faculty and to identify its mitigating and moderating effects. Data has been collected and analyzed from pre- and post- training surveys, interviews, and focus groups. In addition, the project studies WATTS effects on student writing pre- and post-tutoring. The team will use these results to develop a replicable, sustainable model for future expansion to other institutions and fields. By systematically collecting data and testing WATTS, the investigators will be able to identify its mitigating and moderating effects on different stakeholders and contribute valuable knowledge to STEM fields. This approach assesses the elements of the model that have the most impact and the extent to which WATTS can be used to increase collaboration between engineering instructors and writing centers. The project enables the investigators to expand WATTS to additional engineering courses, test key factors with more instructors, refine the process, and position WATTS for dissemination to a broad audience. As the cost of higher education rises, institutions are pressured to graduate students in four years and engineering curricula are becoming more complex. WATTS presents an economical, effective method to improve student writing in the discipline. Several factors indicate that it has the potential for broad dissemination and impact and will provide a foundation for a sustainable model for future work, as instructors become trainers for their colleagues, allowing additional ongoing expansion and implementation. WATTS serves as a model for institutions (large or small) to capitalize on existing infrastructure and resources to achieve large-scale improvements to undergraduate STEM writing while increasing interdisciplinary collaboration and institutional support. 

Single crystals of BaTiO3 exhibit small switching fields and energies, but thin-film performance is considerably worse, thus precluding their use in next-generation devices. Here, we demonstrate high-quality BaTiO3 thin films with nearly bulk-like properties. Thickness scaling provides access to the coercive voltages (<100 mV) and fields (<10 kV cm−1) required for future applications and results in a switching energy of <2 J cm−3 (corresponding to <2 aJ per bit in a 10 × 10 × 10 nm3 device). While reduction in film thickness reduces coercive voltage, it does so at the expense of remanent polarization. Depolarization fields impact polar state stability in thicker films but fortunately suppress the coercive field, thus driving a deviation from Janovec–Kay–Dunn scaling and enabling a constant coercive field for films <150 nm in thickness. Switching studies reveal fast speeds (switching times of ~2 ns for 25-nm-thick films with 5-µm-diameter capacitors) and a pathway to subnanosecond switching. Finally, integration of BaTiO3 thin films onto silicon substrates is shown. We also discuss what remains to be demonstrated to enable the use of these materials for next-generation devices. 

Gravitational lensing by massive objects along the line of sight to the source causes distortions to gravitational wave (GW) signals; such distortions may reveal information about fundamental physics, cosmology, and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO-Virgo network. We search for repeated signals from strong lensing by (1) performing targeted searches for subthreshold signals, (2) calculating the degree of overlap among the intrinsic parameters and sky location of pairs of signals, (3) comparing the similarities of the spectrograms among pairs of signals, and (4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by (1) frequency-independent phase shifts in strongly lensed images, and (2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the nondetection of GW lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects.

 

We report the observation of a coalescing compact binary with component masses 2.5–4.5M_⊙and 1.2–2.0M_⊙(all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO–Virgo–KAGRA detector network on 2023 May 29 by the LIGO Livingston observatory. The primary component of the source has a mass less than 5M_⊙at 99% credibility. We cannot definitively determine from gravitational-wave data alone whether either component of the source is a neutron star or a black hole. However, given existing estimates of the maximum neutron star mass, we find the most probable interpretation of the source to be the coalescence of a neutron star with a black hole that has a mass between the most massive neutron stars and the least massive black holes observed in the Galaxy. We provisionally estimate a merger rate density of${55}_{-47}^{+127}{\mathrm{Gpc}}^{-3}{\mathrm{yr}}^{-1}$for compact binary coalescences with properties similar to the source of GW230529_181500; assuming that the source is a neutron star–black hole merger, GW230529_181500-like sources may make up the majority of neutron star–black hole coalescences. The discovery of this system implies an increase in the expected rate of neutron star–black hole mergers with electromagnetic counterparts and provides further evidence for compact objects existing within the purported lower mass gap.

 

We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers.