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No full textAttosecond pulses in the optical regime, formed as solitons during infrared laser-pulse compression in a hollow-core fibre, may open up attosecond science in molecules and solids
LIGO Detector Characterization in the first half of the fourth Observing run
Get PDFProgress in gravitational-wave (GW) astronomy depends upon having sensitive detectors with good data quality. Since the end of the Laser Interferometer Gravitational-Wave Observatory-Virgo-KAGRA third Observing run in March 2020, detector-characterization efforts have lead to increased sensitivity of the detectors, swifter validation of GW candidates and improved tools used for data-quality products. In this article, we discuss these efforts in detail and their impact on our ability to detect and study GWs. These include the multiple instrumental investigations that led to reduction in transient noise, along with the work to improve software tools used to examine the detectors data-quality. We end with a brief discussion on the role and requirements of detector characterization as the sensitivity of our detectors further improves in the future Observing runs
Where Do You Know From? Nurturing Diaspora Literacy across Latinx Geographies, Abya Yala y el Mundo
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Transcriptome and Gene Expression Profiling of Sweetpotato Responses to Nitrogen and Phosphorus Deficiency During Storage Root Formation
No full textNitrogen (N) and phosphorus (P) are essential macronutrients required by plants for normal growth and development. In sweetpotato [Ipomoea batatas (L.) Lam.], these nutrients are the most limiting factors affecting both yield quality and quantity. While most research focuses on agronomic responses and genomic analyses, limited research has examined transcriptomic responses to nutrient stress in sweetpotato. Here, we employed next-generation sequencing to investigate the molecular mechanisms underlying N and P deficiency responses in cultivar \u27Bayou Belle\u27 (BB). We utilized root tip tissue and investigated responses during the critical stage of root development and storage root formation at 5, 10, and 15 days after planting (DAP). To the best of our knowledge, this represents the first transcriptome-wide study on N deficiency responses in sweetpotato. Our results show that BB exhibits distinct early (5 DAP) and sustained late (10–15 DAP) gene expression patterns. BB prioritizes nitrogen remobilization through early NRT2.7 activation while demonstrating preferential ammonium-based metabolism, with ammonium transporters and assimilation enzyme, upregulated at all timepoints. In contrast, nitrate assimilation enzymes were suppressed across timepoints. Notably, copper amine oxidases were upregulated, providing ROS-mediated stress tolerance and internal ammonium sources. Enhanced alanine, aspartate, and glutamate metabolism at 10–15 DAP was also observed. Under low P conditions, BB demonstrates time-specific regulation of P transport with initial sensing and recognition occurring at 5 DAP and upregulation of transporters at 10-15 DAP. Root architectural attributes remained comparable to P-sufficient plants despite significant height reduction. BB also employed phosphate-scavenging strategies through purple acid phosphatases and aluminum-activated malate transporter at 10–15 DAP. Further analysis of phosphate starvation-responsive genes among sweetpotato cultivars reveals cultivar-specific gene expression changes, highlighting differences in Pi response. Collectively, these results demonstrate that sweetpotato employs coordinated, stage- and cultivar-specific transcriptional responses to manage N and P deficiencies. Understanding these molecular strategies provides a foundation for developing nutrient-efficient cultivars and optimizing fertilizer recommendations, while achieving economic yields
An Andragogical, Transtheoretical Approach to Professional Development Using Structured Video Self-Reflection
No full textThe purpose of this multiple baseline study was to measure the reliability of teachers’ reflective practices and the impact of structured video self-reflection on observable teaching practices and teacher self-efficacy. Additionally, this study explored the implications of teacher self-efficacy, and the stages of change model when working with teachers who have determined a change of behavior is necessary. Designed to satisfy the tenets of andragogy, this study presented structured video self-reflection as a teacher directed, practical, cost-effective form of professional development. Results indicated that teachers were able to reliably self-reflect, and that structured video self-reflection led to positive increases in observable behaviors as measured by the Classroom Assessment Scoring System (CLASS) tool. Stage of change data was used to inform feedback to assist teachers in meeting reliability as well as in an additional phase change for one teacher who required extra support. Self-efficacy results were mixed, showing growth for one teacher and more accurate self-scoring for two teachers
easyspec: An Open-source Python Package for Long-slit Spectroscopy
No full textIn modern-day astronomy, near-infrared, optical, and ultraviolet spectroscopy are indispensable for studying a wide range of phenomena, from measuring black hole masses to analyzing chemical abundances in stellar atmospheres. However, spectroscopic data reduction is often performed using instrument-specific pipelines or legacy software well-established and robust within the community that are often challenging to implement and script in modern astrophysical workflows. In this work, we introduce easyspec, a new Python package designed for long-slit spectroscopy, capable of reducing, extracting, and analyzing spectra from a wide range of instruments—provided they deliver raw FITS files, the standard format for most optical telescopes worldwide. This package is built upon the well-established long-slit spectroscopy routines of the Image Reduction and Analysis Facility (IRAF), integrating modern coding techniques and advanced fitting algorithms based on Markov chain Monte Carlo simulations. We present a user-friendly open-source Python package that can be easily incorporated into customized pipelines for more complex analyses. To validate its capabilities, we apply easyspec to the active galactic nucleus G4Jy 1709, observed with the DOLORES spectrograph at the Telescopio Nazionale Galileo, measuring its redshift and estimating its supermassive black hole mass. Finally, we compare our results with a previous IRAF-based study
Precision Spectral Measurements of Chromium and Titanium from 10 to 250 GeV/n and Sub-Iron to Iron Ratio with the Calorimetric Electron Telescope on the International Space Station
No full textThe Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray (CR) iron and sub-iron events over a wide energy interval. In this Letter, we report an update of our previous measurement of the iron flux and we present-for the first time-a high statistics measurement of the spectra of two sub-iron elements Cr and Ti in the energy interval from 10 to 250 GeV/n. The analyses are based on 8 years of data. Differently from older generations of cosmic-ray instruments which, in most cases, could not resolve individual sub-iron elements, CALET can identify each nuclear species from proton to nickel (and beyond) with a measurement of their electric charge. Thanks to the improvement in statistics and a more refined assessment of systematic uncertainties, the iron spectral shape is better resolved, at high energy, than in our previous paper, and we report its flux ratio to chromium and titanium. The measured fluxes of Cr and Ti show energy dependences compatible with a single power law with spectral indices -2.74±0.06 and -2.88±0.06, respectively