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Barnard’s Loop is a famous arc of Hα emission located in the Orion star-forming region. Here, we provide evidence of a possible formation mechanism for Barnard’s Loop and compare our results with recent work suggesting a major feedback event occurred in the region around 6 Myr ago. We present a 3D model of the large-scale Orion region, indicating coherent, radial, 3D expansion of the OBP-Near/Briceño-1 (OBP-B1) cluster in the middle of a large dust cavity. The large-scale gas in the region also appears to be expanding from a central point, originally proposed to be Orion X. OBP-B1 appears to serve as another possible center, and we evaluate whether Orion X or OBP-B1 is more likely to be the cause of the expansion. Recent 3D dust maps are used to characterize the 3D topology of the entire region, which shows Barnard’s Loop’s correspondence with a large dust cavity around the OPB-B1 cluster. The molecular clouds Orion A, Orion B, and Orion λ reside on the shell of this cavity. Simple estimates of gravitational effects from both stars and gas indicate that the expansion of this asymmetric cavity likely induced anisotropy in the kinematics of OBP-B1. We conclude that feedback from OBP-B1 has affected the structure of the Orion A, Orion B, and Orion λ molecular clouds and may have played a major role in the formation of Barnard’s Loop.

We present a 3D map of magnetic field orientation on the surface of the Local Bubble. This map is the first of its kind to fully chart magnetic fields over an observed superbubble. Recent work mapping the 3D shape and dynamics of the Local Bubble has revealed that the formation of all young stars within 200 pc of the Sun was triggered by the Bubble’s rapid expansion. The exact mechanics of this expansion, and the role that magnetic fields in the surrounding interstellar medium have played in regulating its evolution, is not yet clear. By combining detailed models of the Bubble’s geometry (derived from 3D dust mapping) with the assumption that magnetic field vectors are tangent to the Bubble’s surface, we are able to infer the 3D magnetic field orientation from Planck plane-of-the-sky dust polarization orientations. We analyze the relationship between the Bubble’s inferred magnetic field and background starlight polarimetry observations, and discuss how magnetic fields may have affected the dynamics of the Local Bubble and other nearby structures in the ISM.

VISIONS is an ESO public survey of five nearby (d < 500 pc) star-forming molecular cloud complexes that are canonically associated with the constellations of Chamaeleon, Corona Australis, Lupus, Ophiuchus, and Orion. The survey was carried out with VISTA, using VIRCAM, and collected data in the near-infrared passbands J, H, and Ks. With a total on-sky exposure time of 49.4 h VISIONS covers an area of 650 deg$^2$, and it was designed to build an infrared legacy archive similar to that of 2MASS. Taking place between April 2017 and March 2022, the observations yielded approximately 1.15 million images, which comprise 19 TB of raw data. The observations are grouped into three different subsurveys: The wide subsurvey comprises shallow, large-scale observations and has visited the star-forming complexes six times over the course of its execution. The deep subsurvey of dedicated high-sensitivity observations has collected data on the areas with the largest amounts of dust extinction. The control subsurvey includes observations of areas of low-to-negligible dust extinction. Using this strategy, the VISIONS survey offers multi-epoch position measurements, is able to access deeply embedded objects, and provides a baseline for statistical comparisons and sample completeness. In particular, VISIONS is designed to measure the proper motions of point sources with a precision of 1 mas/yr or better, when complemented with data from VHS. Hence, VISIONS can provide proper motions for sources inaccessible to Gaia. VISIONS will enable addressing a range of topics, including the 3D distribution and motion of embedded stars and the nearby interstellar medium, the identification and characterization of young stellar objects, the formation and evolution of embedded stellar clusters and their initial mass function, as well as the characteristics of interstellar dust and the reddening law., Accepted for publication in Astronomy & Astrophysics on 19 January 2023

We present an analysis of the kinematics of the Radcliffe Wave, a 2.7-kpc-long sinusoidal band of molecular clouds in the solar neighborhood recently detected via 3D dust mapping. With Gaia DR2 astrometry and spectroscopy, we analyze the 3D space velocities of $\sim 1500$ young stars along the Radcliffe Wave in action-angle space, using the motion of the wave's newly born stars as a proxy for its gas motion. We find that the vertical angle of young stars -- corresponding to their orbital phase perpendicular to the Galactic plane -- varies significantly as a function of position along the structure, in a pattern potentially consistent with a wave-like oscillation. This kind of oscillation is not seen in a control sample of older stars from Gaia occupying the same volume, disfavouring formation channels caused by long-lived physical processes. We use a ``wavy midplane'' model to try to account for the trend in vertical angles seen in young stars, and find that while the best-fit parameters for the wave's spatial period and amplitude are qualitatively consistent with the existing morphology defined by 3D dust, there is no evidence for additional velocity structure. These results support more recent and/or transitory processes in the formation of the Radcliffe Wave, which would primarily affect the motion of the wave's gaseous material. Comparisons of our results with new and upcoming simulations, in conjunction with new stellar radial velocity measurements in Gaia DR3, should allow us to further discriminate between various competing hypotheses., Accepted for publication in ApJ

The primary goal of this exploratory mixed-methods study was to obtain a deeper understanding of center-based child care providers serving infants and toddlers. Secondarily, we explored the potenti...

Barnard's Loop is a famous arc of H$\alpha$ emission located in the Orion star-forming region. Here, we provide evidence of a possible formation mechanism for Barnard's Loop and compare our results with recent work suggesting a major feedback event occurred in the region around 6 Myr ago. We present a 3D model of the large-scale Orion region, indicating coherent, radial, 3D expansion of the OBP-Near/Brice\~{n}o-1 (OBP-B1) cluster in the middle of a large dust cavity. The large-scale gas in the region also appears to be expanding from a central point, originally proposed to be Orion X. OBP-B1 appears to serve as another possible center, and we evaluate whether Orion X or OBP-B1 is more likely to be the cause of the expansion. We find that neither cluster served as the single expansion center, but rather a combination of feedback from both likely propelled the expansion. Recent 3D dust maps are used to characterize the 3D topology of the entire region, which shows Barnard's Loop's correspondence with a large dust cavity around the OPB-B1 cluster. The molecular clouds Orion A, Orion B, and Orion $\lambda$ reside on the shell of this cavity. Simple estimates of gravitational effects from both stars and gas indicate that the expansion of this asymmetric cavity likely induced anisotropy in the kinematics of OBP-B1. We conclude that feedback from OBP-B1 has affected the structure of the Orion A, Orion B, and Orion $\lambda$ molecular clouds and may have played a major role in the formation of Barnard's Loop., Comment: 25 pages, 10 figures. Submitted to ApJ

Star formation primarily occurs in filaments where magnetic fields are expected to be dynamically important. The largest and densest filaments trace spiral structure within galaxies. Over a dozen of these dense ($\sim$10$^4$\,cm$^{-3}$) and long ($>$10\,pc) filaments have been found within the Milky Way, and they are often referred to as "bones." Until now, none of these bones have had their magnetic field resolved and mapped in their entirety. We introduce the SOFIA legacy project FIELDMAPS which has begun mapping $\sim$10 of these Milky Way bones using the HAWC+ instrument at 214\,$��$m and 18$\farcs$2 resolution. Here we present a first result from this survey on the $\sim$60\,pc long bone G47. Contrary to some studies of dense filaments in the Galactic plane, we find that the magnetic field is often not perpendicular to the spine (i.e., the center-line of the bone). Fields tend to be perpendicular in the densest areas of active star formation and more parallel or random in other areas. The average field is neither parallel or perpendicular to the Galactic plane nor the bone. The magnetic field strengths along the spine typically vary from $\sim$20 to $\sim$100\,$��$G. Magnetic fields tend to be strong enough to suppress collapse along much of the bone, but for areas that are most active in star formation, the fields are notably less able to resist gravitational collapse., Accepted to ApJL; typo in author list metadata corrected

We report that mice with closed-head multiple traumatic brain injury (TBI) show a decrease in the motoric aspects of generalized arousal, as measured by automated, quantitative behavioral assays. Further, we found that temporally-patterned deep brain stimulation (DBS) can increase generalized arousal and spontaneous motor activity in this mouse model of TBI. This arousal increase is input-pattern-dependent, as changing the temporal pattern of DBS can modulate its effect on motor activity. Finally, an extensive examination of mouse behavioral capacities, looking for deficits in this model of TBI, suggest that the strongest effects of TBI in this model are found in the initiation of any kind of movement.

A well-instrumented Green Bank Telescope (GBT) operating at high frequency represents a unique scientific resource for the US community. As a filled-aperture, 100m-diameter telescope, the GBT is ideally suited to fast mapping of extended, low surface brightness emission with excellent instantaneous frequency coverage. This capability makes the GBT a key facility for a range of cutting edge science described in this document, only possible at these frequencies. We note that the ability to perform the necessary observations is unique and highly complementary to the capabilities offered by interferometers, and should be preserved. We argue that rather than divesting from this exceptional resource, it makes sense for the US community to invest moderately to maintain GBT operations and to instrument it in an optimal manner, enabling it to become an extraordinary complement to existing and future radio interferometers. Adequately instrumented, the GBT would be a pillar for 20-115 GHz science in the US and the world.

We present two Very Large Array observations of the pre-main-sequence star PV Cephei, taken with a separation of 10.5 years. These data show that the proper motions of this star are $\mu_\alpha \cos \delta = +10.9 \pm 3.0$ mas yr$^{-1}$; $\mu_\delta = +0.2 \pm 1.8$ mas yr$^{-1}$, very similar to those -previously known- of HD 200775, the B2Ve star that dominates the illumination of the nearby reflection nebula NGC 7023. This result suggests that PV Cephei is not a rapidly moving run-away star as suggested by previous studies. The large velocity of PV Cephei had been inferred from the systematic eastward displacement of the bisectors of successive pairs of Herbig Haro knots along its flow. These systematic shifts might instead result from an intrinsic dissymmetry in the ejection mechanisms, or from an asymmetric distribution of the circumstellar material., Comment: 15 pages, 2 figures; accepted for publication in RevMexAA

The ability to represent scientific data and concepts visually is becoming increasingly important due to the unprecedented exponential growth of computational power during the present digital age. The data sets and simulations scientists in all fields can now create are literally thousands of times as large as those created just 20 years ago. Historically successful methods for data visualization can, and should, be applied to today's huge data sets, but new approaches, also enabled by technology, are needed as well. Increasingly, "modular craftsmanship" will be applied, as relevant functionality from the graphically and technically best tools for a job are combined as-needed, without low-level programming., Comment: 4 pages, including 3 figures. To appear in Proceedings of the International Festival of Scientific Visualization, held in Tokyo, Japan, March 2009. Publisher will be Universal Academy Press

Almost all young stars are found in multiple systems. This suggests that protostellar cores almost always fragment into multiple objects. The observed properties of multiple systems such as their separation distribution and mass ratios provide strong constraints on star formation theories. We review the observed properties of young and old multiple systems and find that the multiplicity of stars changes. Such an evolution is probably due to (a) the dynamical decay of small-N systems and/or (b) the destruction of multiple systems within dense clusters. We review simulations of the fragmentation of rotating and turbulent molecular cores. Such models almost always produce multiple systems, however the properties of those systems do not match observations at all well. Magnetic fields appear to supress fragmentation, prehaps suggesting that they are not dynamically important in the formation of multiple systems. We finish by discussing possible reasons why theory fails to match observation, and the future prospects for this field., Comment: 16 pages, 6 figures. To appear in 'Protostars and Planets V'. Includes proto.cls style file. Figures degraded in quality, full version available by anonymous ftp (ftp:astro.shef.ac.uk, pub/spg/GoodwinPPV.pdf.gz)

3D Slicer, a brain imaging and visualization computer application developed at Brigham and Women's Hospital's Surgical Planning Lab, was used to visualize the IC 348 star-forming complex in Perseus in RA-DEC-Velocity space. This project is part of a collaboration between Harvard University's Astronomy Department and Medical School, and serves as a proof-of-concept technology demonstration for Harvard's Institute for Innovative Computing (IIC). 3D Slicer is capable of displaying volumes (data cubes), slices in any direction through the volume, 3D models generated from the volume, and 3D models of label maps. The 3D spectral line maps of IC 348 were created using 13CO and C18O data collected at the FCRAO (Five College Radio Astronomy Observatory). The 3D visualization makes the identification of the cloud's inner dense cores and velocity structure components easier than current conventional astronomical methods. It is planned for 3D Slicer to be enhanced with astrophysics-specific features resulting in an astronomical version to be available online through the IIC and in conjunction with the National Virtual Observatory (NVO)., Comment: Single PDF document. Uncompressed version available from http://cfa-www.harvard.edu/COMPLETE

Super-sonic turbulence fragments molecular clouds (MC) into a very complex density field with density contrasts of several orders of magnitude. A fraction of the gas is locked into dense and gravitationally bound cores, which collapse as proto-stars. This process can be studied with numerical simulations of super-sonic self-gravitating turbulence. In this work, we use numerical simulations of magneto-hydrodynamic (MHD), super-sonic, super-Alfv\'{e}nic and self-gravitating turbulence to compute the mass distribution of collapsing proto-stellar cores, which are selected as local density maxima. We find that the mass distribution of collapsing cores is consistent with the stellar initial mass function (IMF), suggesting that super-sonic turbulence may be responsible for the generation of the IMF. To support this conclusion we also show that the physical properties of the numerically selected cores are in agreement with the properties of observed NH$_3$ cores and that their magnetic field strength is consistent with Zeeman splitting measurements. In turbulent MCs, star formation occurs via the gravitational collapse of super-critical cores, formed by the turbulent flow, sub-critical cores being irrelevant for the process of star formation., Comment: 15 pages, 5 figures, submitted to ApJ

Abstract 3815 Poster Board III-751 Following initial promising clinical results reported at ASH 2008 (Shenoy et al) in RAEB MDS and AML patients treated with the new investigational agent ON 01910.Na, we have initiated a phase 1/2 single arm escalating dose study in advanced MDS patients with a shorter schedule of administration of ON 01910.Na. The first 13 patients enrolled in our ongoing trial (6 high risk, 1 Intermediate-2 and 5 Intermediate-1 according to IPSS classification; 7 females/6 males, age range: 47-83ys), most of them having failed prior MDS therapies were administered ON 01910.Na as a 48 h continuous intravenous infusion weekly for 3 weeks of a 4-week cycle. Ten patients were treated at the 800 mg/m2/day dose level and 3 at the 1500 mg/m2/day dose level for 4 to 27+ weeks (1 to 6 four-week cycles). Most patients had grade 3 or 4 cytopenias at baseline. Overall the therapy was well tolerated and a few patients reported improvements of well being and pain relief. The most frequently reported adverse events were thrombocytopenia, neutropenia, anemia, fatigue and nausea. Serious adverse events were typical of this patient population and none of them was related to ON 01910.Na except for one case of neutropenia. Bone marrow blastic response was evaluated by bone marrow morphology. Five patients had a pretreatment blast count lower than 5% and no worsening of blast count was observed in the 3 patients who had follow-up bone marrow examination. Another six patients had more than 5% pretreatment bone marrow blasts. Among these patients, two had significant decreases in blast counts compared to pre-treatment values, while two showed stabilization and two progressed. Two patients had hematological improvements (neutrophil and erythroid responses). These results are encouraging and the trial is continuing. Patient Bone Marrow Blasts Hematological Improvement Pre-Treatment 4-8 week Follow-up 1 Disclosures: Wilhelm: Onconova: Employment.

Chapter 1 establishes the plausibility of “magnetic molecular clouds.” We show that the empirically known relations between spectral line width, density, and cloud size can be derived from a virial equilibrium model where gravity is balanced by the sum of magnetic and pressure support. And, we show that sub­stitution of measured density, cloud size, and line width measurements into the model can predict observed field strength (as compared with Zeeman observa­tions) to within a factor of two. In Chapter 2, we discuss the Zeeman effect and we present new measure­ ments of magnetic field strength based on OH and HI Zeeman observations at the Arecibo(305-m) and Green Bank (43-m) telescopes. The Barnard 1 (Bl) re­gion, in the Perseus Molecular Cloud Complex, is discussed in detail. We present OH spectral line intensity maps of the regions where the OH Zeeman effect was observed, which allow, for the first time, comparison of observed field strength values with predicted field strength values (based on observed line width, den­sity, and cloud size), using emission from a single molecular species. The fields measured are consistent with the equilibrium model of Chapter 1, and with other models. Chapter 3 is an investigation of the spatial structure of magnetic fields in molecular clouds. We present new optical polarization maps of dark clouds in Perseus, Taurus, and Ophiuchus. The polarization observed is attributed to pref­ erential extinction of background starlight by magnetically aligned dust grains in the clouds, and we analyze the polarization maps as maps of the projection of the magnetic field onto the plane of the sky. As in previous studies, the field traced by the polarization vectors is smooth in appearance, and has a well-defined uniform component, although it is not generally oriented at a special angle (i.e. 0° or 90°) to filamentary dark clouds. The dispersion in the position angle of the polarization vectors for an entire cloud complex is generally less than the varia­ tion in position angle of the long axis of filamentary clouds within the complex, suggesting that the magnetic field does not dominate the cloud structure on the size scale ~1 pc, although its energy, as discussed in Chapters 1 and 2, is still comparable to the energy in the gas motions.&nbsp

The AstroMed project at Harvard University's Initiative in Innovative Computing (IIC) is working on improved visualization and data sharing solutions applicable to the fields of both astronomy and medicine. The current focus is on the application of medical imaging visualization and analysis techniques to three-dimensional astronomical data. The 3D Slicer and OsiriX medical imaging tools have been used to make isosurface and volumetric models in RA-DEC-velocity space of the Perseus star forming region from the COMPLETE Survey of Star Forming Region's spectral line maps. 3D Slicer, a brain imaging and visualization computer application developed at Brigham and Women's Hospital's Surgical Planning Lab, is capable of displaying volumes (i.e. data cubes), displaying slices in any direction through the volume, generating 3D isosurface models from the volume which can be viewed and rotated in 3D space, and making 3D models of label maps (for example CLUMPFIND output). OsiriX is able to generate volumetric models from data cubes and allows the user in real time to change the displayed intensity level, crop the models without losing the data, manipulate the model and viewing angle, and use a variety of projections. In applying 3D Slicer to 12CO and 13CO spectral line data cubes of Perseus, the visualization allowed for a rapid review of over 8 square degrees and 150,000 spectra, and the cataloging of 217 high velocity points. These points were further investigated in half of Perseus and all known outflows were detected, and 20 points were identified in these regions as possibly being associated with undocumented outflows. All IIC developed tools, as well as 3D Slicer and OsiriX, are freely available., 4 pages, 2 figures. To be published in the Astronomical Data Analysis Software and Systems XVI ASP Conference Series, Proceedings of the Conference Held 15-18 October 2006 in Tucson, Arizona, USA

The VAO (Virtual Astronomical Observatory) Science Council (VAO-SC) met on July 27-28, 2011 at the Harvard-Smithsonian Center for Astrophysics in Cambridge MA, to review the VAO performance during its first year of operations. In this meeting the VAO demonstrated the new tools for astronomers that are being released in September 2011 and presented plans for the second year of activities, resulting from studies conducted during the first year. This document contains the recommendations of the VAO-SC for the second year of activity of the VAO., 6 pages

Star formation in molecular clouds can be triggered by the dynamical action of winds from massive stars. Furthermore, X-ray and UV fluxes from massive stars can influence the life time of surrounding circumstellar disks. We present the results of a 53 ks XMM-Newton observation centered on the Rho Ophiuchi A+B binary system. Rho Ophiiuchi lies in the center of a ring of dust, likely formed by the action of its winds. This region is different from the dense core of the cloud (L1688 Core F) where star formation is at work. X-rays are detected from Rho Ophiuchi as well as a group of surrounding X-ray sources. We detected 89 X-ray sources, 47 of them have at least one counterpart in 2MASS + All-WISE catalogs. Based on IR and X-ray properties, we can distinguish between young stellar objects (YSOs) belonging to the cloud and background objects. Among the cloud members, we detect 3 debris disk objects and 22 disk-less / Class III young stars. We show that these stars have ages in $5-10$ Myr, and are significantly older than the YSOs in L1688. We speculate that they are the result of an early burst of star formation in the cloud. An X-ray energy of $\ge5\times10^{44}$ ergs has been injected into the surrounding medium during the past $5$ Myr, we discuss the effects of such energy budget in relation to the cloud properties and dynamics., Comment: 17 pages, 9 figures, 7 tables. Accepted for publication to Astronomy & Astrophysics

Recommendations of the VAO-Science Council following the meeting of March 26-27, 2010. Refer to the webpage http://www.aui.edu/vao.php, 9 pages, no figures - refer to the webpage http://www.aui.edu/vao.php