Polarity and Competition in the Development of the Calyx of Held Terminal in the Medial Nucleus of the Trapezoid Body in the Mouse

In the auditory brainstem, the connection between globular bushy cells of the anteroventral cochlear nucleus and principal cells (PCs) of the medial nucleus of the trapezoid body (MNTB) is created by one of the largest nerve terminals in the central nervous system, the calyx of Held (CH). The characteristics of the CH:MNTB connection—a short developmental period (48-72 hours), accessibility for recording from pre- and postsynaptic components, and clear monoinnervated end point—make this system an ideal model system for studying nervous system development. Model systems undergo stereotyped stages of development, including exuberant overinnervation, competition between terminals, and a refinement of innervation through removal of weak inputs. However, unlike other similar model systems (climbing fiber:Purkinje cell, retinal ganglion cells:dorsolateral geniculate nucleus), it has been a long-standing question whether the CH:MNTB system undergoes competition. We investigated the innervation state of PCs using the novel technique of segmentation and 3D reconstruction of PCs and their associated inputs across important developmental timepoints (postnatal days (P)2,3,4,6,9,30). This was accomplished by application of serial block-face scanning electron microscopy (SBEM), a method of serial section electron microscopy providing high spatial resolution (~4-10nm) and a high degree of alignment between images with very little section loss. Applying this technique, we show early exuberant innervation of PCs (P2), establish that competition is a common process, and pinpoint the 24-hour period from P3-P4 as a uniquely active day in CH growth during which terminal contact with PCs increases at a rate exceeding 200 µm2/day. Common morphological characteristics of the CH:MNTB connection also became qualitatively evident based on 3D reconstructions, particularly an eccentric PC nucleus and preference for polarized terminal growth. Based on these observations, we undertook a quantitative study of polarity in CH:MNTB development using our 3D reconstructions. The results of this investigation demonstrate a novel polarity in development of both the CH and PC; developing PCs are characterized by eccentrically placed nuclei that establish an “intrasomatic polarity” that persists through young adulthood (P30). This polarity appears to define a unique territory opposite of the nuclear location that is amenable to growth of the calyx, is enriched in dendrites, and is selectively enlarged as the principal cell matures to create glia-free surface area for innervation. To our knowledge, this is the first report of a polarity program in the coordinated pre- and postsynaptic development of a non-laminar brain region. Additionally, our findings have codified a progression of dendritic pruning in the maturation of principal cells that may influence and be influenced by the developmental state of the cell. Taken in totality, these results indicate a highly polarized, systemic competitive process in the MNTB during the development of the calyx of Held and suggests potential mediators of competition that deserve further study

The TESS-Keck Survey. XV. Precise Properties of 108 TESS Planets and Their Host Stars

We present the stellar and planetary properties for 85 TESS Objects of Interest (TOIs) hosting 108 planet candidates which comprise the TESS-Keck Survey (TKS) sample. We combine photometry, high-resolution spectroscopy, and Gaia parallaxes to measure precise and accurate stellar properties. We then use these parameters as inputs to a lightcurve processing pipeline to recover planetary signals and homogeneously fit their transit properties. Among these transit fits, we detect significant transit-timing variations among at least three multi-planet systems (TOI-1136, TOI-1246, TOI-1339) and at least one single-planet system (TOI-1279). We also reduce the uncertainties on planet-to-star radius ratios $R_p/R_\star$ across our sample, from a median fractional uncertainty of 8.8$\%$ among the original TOI Catalog values to 3.0$\%$ among our updated results. With this improvement, we are able to recover the Radius Gap among small TKS planets and find that the topology of the Radius Gap among our sample is broadly consistent with that measured among Kepler planets. The stellar and planetary properties presented here will facilitate follow-up investigations of both individual TOIs and broader trends in planet properties, system dynamics, and the evolution of planetary systems.Comment: Accepted at The Astronomical Journal; 21 pages, 9 figure

Catching Element Formation In The Act

Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.Comment: 14 pages including 3 figure

The TESS-Keck Survey. XVI. Mass Measurements for 12 Planets in Eight Systems

With JWST's successful deployment and unexpectedly high fuel reserves, measuring the masses of sub-Neptunes transiting bright, nearby stars will soon become the bottleneck for characterizing the atmospheres of small exoplanets via transmission spectroscopy. Using a carefully curated target list and more than two years' worth of APF-Levy and Keck-HIRES Doppler monitoring, the TESS-Keck Survey is working toward alleviating this pressure. Here we present mass measurements for 11 transiting planets in eight systems that are particularly suited to atmospheric follow-up with JWST. We also report the discovery and confirmation of a temperate super-Jovian-mass planet on a moderately eccentric orbit. The sample of eight host stars, which includes one subgiant, spans early-K to late-F spectral types ($T_\mathrm{eff} =$ 5200--6200 K). We homogeneously derive planet parameters using a joint photometry and radial velocity modeling framework, discuss the planets' possible bulk compositions, and comment on their prospects for atmospheric characterization.Comment: Accepted for publication in The Astronomical Journal on 2023-Jun-22. 60 pages, 17 Tables, 28 Figure

The TESS-Keck Survey. XI. Mass Measurements for Four Transiting sub-Neptunes orbiting K dwarf TOI-1246

Multi-planet systems are valuable arenas for investigating exoplanet architectures and comparing planetary siblings. TOI-1246 is one such system, with a moderately bright K dwarf (V=11.6, K=9.9) and four transiting sub-Neptunes identified by TESS with orbital periods of 4.31 d, 5.90 d, 18.66 d, and 37.92 d. We collected 130 radial velocity observations with Keck/HIRES and TNG/HARPS-N to measure planet masses. We refit the 14 sectors of TESS photometry to refine planet radii (2.97±0.06 R⊕,2.47±0.08 R⊕,3.46±0.09 R⊕, 3.72±0.16 R⊕), and confirm the four planets. We find that TOI-1246 e is substantially more massive than the three inner planets (8.1±1.1M⊕, 8.8±1.2M⊕, 5.3±1.7M⊕, 14.8±2.3M⊕). The two outer planets, TOI-1246 d and TOI-1246 e, lie near to the 2:1 resonance (Pe/Pd=2.03) and exhibit transit timing variations. TOI-1246 is one of the brightest four-planet systems, making it amenable for continued observations. It is one of only six systems with measured masses and radii for all four transiting planets. The planet densities range from 0.70±0.24 to 3.21±0.44g/cm3, implying a range of bulk and atmospheric compositions. We also report a fifth planet candidate found in the RV data with a minimum mass of 25.6 ± 3.6 M⊕. This planet candidate is exterior to TOI-1246 e with a candidate period of 93.8 d, and we discuss the implications if it is confirmed to be planetary in nature

The TESS-Keck Survey. XI. Mass Measurements for Four Transiting Sub-Neptunes Orbiting K Dwarf TOI-1246

Multiplanet systems are valuable arenas for investigating exoplanet architectures and comparing planetary siblings. TOI-1246 is one such system, with a moderately bright K dwarf (V = 11.6, K = 9.9) and four transiting sub-Neptunes identified by TESS with orbital periods of 4.31, 5.90, 18.66, and 37.92 days. We collected 130 radial velocity observations with Keck/HIRES and TNG/HARPS-N to measure planet masses. We refit the 14 sectors of TESS photometry to refine planet radii (2.97 +/- 0.06 R (circle plus), 2.47 +/- 0.08 R (circle plus), 3.46 +/- 0.09 R (circle plus), and 3.72 +/- 0.16 R (circle plus)) and confirm the four planets. We find that TOI-1246 e is substantially more massive than the three inner planets (8.1 +/- 1.1 M (circle plus), 8.8 +/- 1.2 M (circle plus), 5.3 +/- 1.7 M (circle plus), and 14.8 +/- 2.3 M (circle plus)). The two outer planets, TOI-1246 d and TOI-1246 e, lie near to the 2:1 resonance (P (e)/P ( d ) = 2.03) and exhibit transit-timing variations. TOI-1246 is one of the brightest four-planet systems, making it amenable for continued observations. It is one of only five systems with measured masses and radii for all four transiting planets. The planet densities range from 0.70 +/- 0.24 to 3.21 +/- 0.44 g cm(-3), implying a range of bulk and atmospheric compositions. We also report a fifth planet candidate found in the RV data with a minimum mass of 25.6 +/- 3.6 M (circle plus). This planet candidate is exterior to TOI-1246 e, with a candidate period of 93.8 days, and we discuss the implications if it is confirmed to be planetary in nature

Narrative theology in Religious Education

This is an Author's Accepted Manuscript of an article published in British Journal of Religious Education, 20 March 2013. Copyright © 2013 Taylor & Francis. Available online at: http://www.tandfonline.com/10.1080/01416200.2013.785931This article advocates a pedagogy of Religious Education (RE) based upon a narratival framework informed by both narrative theology and narrative philosophy. Drawing on the work of narrative theologians including Stanley Hauerwas, the article outlines the nature of the framework, describes the four phases of learning that comprise the pedagogy, and explains how such an approach can overcome existing difficulties in how biblical texts are handled within RE. Working from the narrative assumption that individuals and communities are formed by reading, sharing and living within stories, it suggests that the pedagogy might encourage pupils to think about how the lives of Christians are shaped by their interpretations of biblical narratives, to offer their own interpretations of biblical and other texts, and to consider the stories – religious, non-religious or both – which shape their own lives. In so doing, the article moves away from a ‘proof-texting’ approach to the Bible towards one in which pupils are enabled to think about the significance of biblical narratives for both Christians and themselves

A PROCESS TO SCORE FUTURES COMMAND R&D EFFORTS AND PROVIDE A DECISION SUPPORT TOOL TO SELECT AND EVALUATE THOSE EFFORTS

Army Futures Command (AFC) manages technology development projects in response to identified threats. These projects support future Multi-Domain Operations (MDO) capabilities, which are diverse in duration, cost, and technical requirements. The potential outcomes range from software upgrades to revolutionary concepts in vehicle or weapons technology. AFC must evaluate each program annually to determine priority and funding levels for recommendation in the Program Objective Memorandum (POM). AFC does not currently have a methodology in place that is capable of scoring projects based on their potential future impacts. This project develops a methodology and common metrics to score diverse technology development projects, and the methodology will provide a decision tool to support AFC POM submission. Due to the complexity of the decision-making model, as well as limits in time and available information, this project develops the methodology up to the point of demonstrating its function with simulated data. Taking these factors into consideration, this project does not perform validation and testing.Civilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyCivilian, Department of the ArmyApproved for public release. distribution is unlimite