| 111. |
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| 112. |
- Tobin, John J., et al.
(författare)
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The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. I. Identifying and Characterizing the Protostellar Content of the OMC-2 FIR4 and OMC-2 FIR3 Regions
- 2019
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 886:1
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Tidskriftsartikel (refereegranskat)abstract
- We present Atacama Large Millimeter/submillimeter Array (0.87 mm) and Very Large Array (9 mm) observations toward OMC-2 FIR4 and OMC-2 FIR3 within the Orion integral-shaped filament, thought to be two of the nearest regions of intermediate-mass star formation. We characterize the continuum sources within these regions on ?40 au (01) scales and associated molecular line emission at a factor of ?30 better resolution than previous observations at similar wavelengths. We identify six compact continuum sources within OMC-2 FIR4, four in OMC-2 FIR3, and one additional source just outside OMC-2 FIR4. This continuum emission is tracing the inner envelope and/or disk emission on less than 100 au scales. HOPS-108 is the only protostar in OMC-2 FIR4 that exhibits emission from high-excitation transitions of complex organic molecules (e.g., methanol and other lines) coincident with the continuum emission. HOPS-370 in OMC-2 FIR3, with L;?;360 L, also exhibits emission from high-excitation methanol and other lines. The methanol emission toward these two protostars is indicative of temperatures high enough to thermally evaporate it from icy dust grains; overall, these protostars have characteristics similar to hot corinos. We do not identify a clear outflow from HOPS-108 in (CO)-C-12, but we find evidence of interaction between the outflow/jet from HOPS-370 and the OMC-2 FIR4 region. A multitude of observational constraints indicate that HOPS-108 is likely a low- to intermediate-mass protostar in its main mass accretion phase and is the most luminous protostar in OMC-2 FIR4. The high-resolution data presented here are essential for disentangling the embedded protostars from their surrounding dusty environments and characterizing them.
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| 113. |
- Tobin, John J., et al.
(författare)
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The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. II. A Statistical Characterization of Class 0 and Class i Protostellar Disks
- 2020
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 1538-4357 .- 0004-637X. ; 890:2
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Tidskriftsartikel (refereegranskat)abstract
- We have conducted a survey of 328 protostars in the Orion molecular clouds with the Atacama Large Millimeter/submillimeter Array at 0.87 mm at a resolution of ∼0.″1 (40 au), including observations with the Very Large Array at 9 mm toward 148 protostars at a resolution of ∼0.″08 (32 au). This is the largest multiwavelength survey of protostars at this resolution by an order of magnitude. We use the dust continuum emission at 0.87 and 9 mm to measure the dust disk radii and masses toward the Class 0, Class I, and flat-spectrum protostars, characterizing the evolution of these disk properties in the protostellar phase. The mean dust disk radii for the Class 0, Class I, and flat-spectrum protostars are 44.9-3.4+5.8, 37.0-3.0+4.9, and 28.5-2.3+3.7 au, respectively, and the mean protostellar dust disk masses are 25.9-4.0+7.7, 14.9-2.2+3.8, 11.6-1.9+3.5 M⊙, respectively. The decrease in dust disk masses is expected from disk evolution and accretion, but the decrease in disk radii may point to the initial conditions of star formation not leading to the systematic growth of disk radii or that radial drift is keeping the dust disk sizes small. At least 146 protostellar disks (35% of 379 detected 0.87 mm continuum sources plus 42 nondetections) have disk radii greater than 50 au in our sample. These properties are not found to vary significantly between different regions within Orion. The protostellar dust disk mass distributions are systematically larger than those of Class II disks by a factor of >4, providing evidence that the cores of giant planets may need to at least begin their formation during the protostellar phase.
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| 114. |
- van der Beek, Justine N., et al.
(författare)
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MRI Characteristics of Pediatric Renal Tumors : A SIOP-RTSG Radiology Panel Delphi Study
- 2022
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Ingår i: Journal of Magnetic Resonance Imaging. - : Wiley. - 1053-1807 .- 1522-2586. ; 55:2, s. 543-552
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Tidskriftsartikel (refereegranskat)abstract
- Background: The SIOP-Renal Tumor Study Group (RTSG) does not advocate invasive procedures to determine histology before the start of therapy. This may induce misdiagnosis-based treatment initiation, but only for a relatively small percentage of approximately 10% of non-Wilms tumors (non-WTs). MRI could be useful for reducing misdiagnosis, but there is no global consensus on differentiating characteristics. Purpose: To identify MRI characteristics that may be used for discrimination of newly diagnosed pediatric renal tumors. Study Type: Consensus process using a Delphi method. Population: Not applicable. Field Strength/Sequence: Abdominal MRI including T1- and T2-weighted imaging, contrast-enhanced MRI, and diffusion-weighted imaging at 1.5 or 3 T. Assessment: Twenty-three radiologists from the SIOP-RTSG radiology panel with ≥5 years of experience in MRI of pediatric renal tumors and/or who had assessed ≥50 MRI scans of pediatric renal tumors in the past 5 years identified potentially discriminatory characteristics in the first questionnaire. These characteristics were scored in the subsequent second round, consisting of 5-point Likert scales, ranking- and multiple choice questions. Statistical Tests: The cut-off value for consensus and agreement among the majority was ≥75% and ≥60%, respectively, with a median of ≥4 on the Likert scale. Results: Consensus on specific characteristics mainly concerned the discrimination between WTs and non-WTs, and WTs and nephrogenic rest(s) (NR)/nephroblastomatosis. The presence of bilateral lesions (75.0%) and NR/nephroblastomatosis (65.0%) were MRI characteristics indicated as specific for the diagnosis of a WT, and 91.3% of the participants agreed that MRI is useful to distinguish NR/nephroblastomatosis from WT. Furthermore, all participants agreed that age influenced their prediction in the discrimination of pediatric renal tumors. Data Conclusion: Although the discrimination of pediatric renal tumors based on MRI remains challenging, this study identified some specific characteristics for tumor subtypes, based on the shared opinion of experts. These results may guide future validation studies and innovative efforts. Level of Evidence: 3. Technical Efficacy Stage: 3.
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| 115. |
- Waites, Peter, 1978-
(författare)
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On the Boundaries of Watchmen : Paratextual Narratives across Media
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation is an intervention into the ongoing revisions of Gerard Genette’s concept of paratexts. Increasingly used in discussions of artifacts other than the literary novels that were Genette’s object of attention, the concept of paratexts has given rise to intense debates regarding the nature and functions of paratextual elements across media. One area of contestation is the relation of paratext to narrative. While Genette’s original paradigm complicates the possibility of a narrative paratext, I show that the liminal zones usually occupied by paratexts—what I call paratextual space—are commonly used for narrative purposes, particularly as popular narratives extend across media. In this dissertation, I analyze the different embodiments of Watchmen with a focus on such a use of paratextual spaces. I argue that studies of narratives presented in these spaces—what I refer to as paratextual narratives—will not only shed light on these narrative strategies, but also give new insights into how popular narratives extend across new media platforms.My first analytical chapter concerns the material that frames the Watchmen graphic narrative, and its roots in the media specific history and paratextual phenomenon known as lettercols. I show how this paratextual space was repurposed in the creation of Watchmen to present narrative material that worked to establish and augment the history of the storyworld and the characters presented in the graphic narrative of the Watchmen comics. I argue that the functions of these materials are influenced by the tradition established by the lettercols and the paratextual spaces in which they are situated. In my second analytical chapter I turn to the Watchmen adaptation, focusing in particular on the digital narratives framing the cinematic premiere of the film. I show how the paratextual nature of these materials occluded their narrative functions, causing them to be excluded from what is regarded the adaptation of Watchmen. I argue that the materials framing the Watchmen film are paratextual narratives that should be seen as integral parts of the Watchmen adaptation. In my conclusion I address the Watchmen prequel-series Before Watchmen and raise questions regarding how paratextual narratives function for media franchising.
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| 116. |
- Warren, Wesley C, et al.
(författare)
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The genome of a songbird
- 2010
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 464:7289, s. 757-762
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Tidskriftsartikel (refereegranskat)abstract
- The zebra finch is an important model organism in several fields with unique relevance to human neuroscience. Like other songbirds, the zebra finch communicates through learned vocalizations, an ability otherwise documented only in humans and a few other animals and lacking in the chicken-the only bird with a sequenced genome until now. Here we present a structural, functional and comparative analysis of the genome sequence of the zebra finch (Taeniopygia guttata), which is a songbird belonging to the large avian order Passeriformes. We find that the overall structures of the genomes are similar in zebra finch and chicken, but they differ in many intrachromosomal rearrangements, lineage-specific gene family expansions, the number of long-terminal-repeat-based retrotransposons, and mechanisms of sex chromosome dosage compensation. We show that song behaviour engages gene regulatory networks in the zebra finch brain, altering the expression of long non-coding RNAs, microRNAs, transcription factors and their targets. We also show evidence for rapid molecular evolution in the songbird lineage of genes that are regulated during song experience. These results indicate an active involvement of the genome in neural processes underlying vocal communication and identify potential genetic substrates for the evolution and regulation of this behaviour.
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| 117. |
- Watson, Christine, 1980-
(författare)
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Tradition and Translation : Maciej Stryjkowski's Polish Chronicle in Seventeenth-Century Russian Manuscripts
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The object of this study is a translation from Polish to Russian of the Polish historian Maciej Stryjkowski’s Kronika Polska, Litewska, Żmódzka i wszystkiej Rusi, made at the Diplomatic Chancellery in Moscow in 1673–79. The original of the chronicle, which relates the origin and early history of the Slavs, was published in 1582. This Russian translation, as well as the other East Slavic translations that are also discussed here, is preserved only in manuscripts, and only small excerpts have previously been published. In the thesis, the twelve extant manuscripts of the 1673–79 translation are described and divided into three groups based on variant readings. It also includes an edition of three chapters of the translation, based on a manuscript kept in Uppsala University Library. There was no standardized written language in 17th-century Russia. Instead, there were several co-existing norms, and the choice depended on the text genre. This study shows that the language of the edited chapters contains both originally Church Slavonic and East Slavic linguistic features, distributed in a way that is typical of the so-called hybrid register. Furthermore, some features vary greatly between manuscripts and between scribes within the manuscripts, which shows that the hybrid register allowed a certain degree of variation. The translation was probably the joint work of several translators. Some minor changes were made in the text during the translation work, syntactic structures not found in the Polish original were occasionally used to emphasize the bookish character of the text, and measurements, names etc. were adapted to Russian norms. Nevertheless, influence from the Polish original can sometimes be noticed on the lexical and syntactic levels. All in all, this thesis is a comprehensive study of the language of the translated chronicle, which is a representative 17th-century text.
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| 118. |
- Watson, David, et al.
(författare)
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Introduction : The Ongoing End
- 2017
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Ingår i: The Ongoing End. - : Routledge. ; , s. 1-5
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Bokkapitel (refereegranskat)
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| 119. |
- Zwitter, Tomaz, et al.
(författare)
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The GALAH survey : accurate radial velocities and library of observed stellar template spectra
- 2018
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 481:1, s. 645-654
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Tidskriftsartikel (refereegranskat)abstract
- GALAH is a large-scale magnitude-limited southern stellar spectroscopic survey. Its second data release (GALAH DR2) provides values of stellar parameters and abundances of 23 elements for 342 682 stars (Buder et al.). Here we add a description of the public release of radial velocities with a typical accuracy of 0.1 km s(-1) for 336 215 of these stars, achievable due to the large wavelength coverage, high resolving power, and good signal-to-noise ratio of the observed spectra, but also because convective motions in stellar atmosphere and gravitational redshift from the star to the observer are taken into account. In the process we derive medians of observed spectra that are nearly noiseless, as they are obtained from between 100 and 1116 observed spectra belonging to the same bin with a width of 50 K in temperature, 0.2 dex in gravity, and 0.1 dex in metallicity. Publicly released 1181 median spectra have a resolving power of 28 000 and trace the well-populated stellar types with metallicities between -0.6 and +0.3. Note that radial velocities from GALAH are an excellent match to the accuracy of velocity components along the sky plane derived by Gaia for the same stars. The level of accuracy achieved here is adequate for studies of dynamics within stellar clusters, associations, and streams in the Galaxy. So it may be relevant for studies of the distribution of dark matter.
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| 120. |
- Zwitter, Tomaž, et al.
(författare)
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The GALAH+ survey : a new library of observed stellar spectra improves radial velocities and hints at motions within M67
- 2021
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Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 508:3, s. 4202-4215
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Tidskriftsartikel (refereegranskat)abstract
- GALAH+ is a magnitude-limited survey of high-resolution stellar spectra obtained by the HERMES spectrograph at the Australian Astronomical Observatory. Its third data release provides reduced spectra with new derivations of stellar parameters and abundances of 30 chemical elements for 584 015 dwarfs and giants, 88 per cent of them in the Gaia magnitude range 11 < G < 14. Here, we use these improved values of stellar parameters to build a library of observed spectra which is useful to study variations of individual spectral lines with stellar parameters. This and other improvements are used to derive radial velocities with uncertainties which are generally within 0.1 km s−1 or ∼25 per cent smaller than in the previous release. Median differences in radial velocities measured here and by the Gaia DR2 or APOGEE DR16 surveys are smaller than 30 m s−1, a larger offset is present only for Gaia measurements of giant stars. We identify 4483 stars with intrinsically variable velocities and 225 stars for which the velocity stays constant over ≥3 visits spanning more than a year. The combination of radial velocities from GALAH+ with distances and sky plane motions from Gaia enables studies of dynamics within streams and clusters. For example, we estimate that the open cluster M67 has a total mass of ∼3300 M⊙ and its outer parts seem to be expanding, though astrometry with a larger time-span than currently available from Gaia eDR3 is needed to judge if the latter result is real.
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