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1
Schatz, Valentin. "Testing the Limits of Jurisdiction in Investor-State Arbitration in Svalbard’s Waters: Peteris Pildegovics and SIA North Star v. Kingdom of Norway." Arctic Review on Law and Politics 12 (2021): 167. http://dx.doi.org/10.23865/arctic.v12.3372.
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On 1 April 2020, the Latvian fishing company SIA North Star and its owner Peteris Pildegovics initiated an investor-State arbitration against Norway (Peteris Pildegovics and SIA North Star v. Kingdom of Norway) at the International Centre for Settlement of Investment Disputes (ICSID). This case is not only Norway’s first ever ICSID case, but also the first publicly known investor-State arbitration in which an operator of a fishing vessel has brought a claim against a coastal State for allegedly unlawful exercise of prescriptive and enforcement jurisdiction in relation to fisheries. The case raises intricate questions concerning the limits of jurisdiction ratione materiae and jurisdiction ratione personae of investment tribunals.
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Pittard, Julian M., Ian R. Stevens, Peredur M. Williams, Andrew M. T. Pollock, Steven L. Skinner, Michael F. Corcoran, and Anthony F. J. Moffat. "High-resolution X-ray imaging of the colliding wind shock in WR 147 (WN8(h)+B0.5V)." Symposium - International Astronomical Union 212 (2003): 222–23. http://dx.doi.org/10.1017/s0074180900212126.
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We present the results of a high-resolution Chandra X-ray image of the Wolf-Rayet binary system WR 147, which consists of a WN8 star and an early-type companion located 0″.6 to its north. The image provides the first direct evidence for spatially extended X-ray emission in an early-type binary system, and shows that the emission peaks north of the WN8 star and close to the position of the radio bow shock. Simulated X-ray images of the wind-wind collision have a fwhm consistent with the data, but cannot account for the full spatial extension, unless emission from the stars is also included.
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Mouritsen, Henrik, and Ole Næsbye Larsen. "Migrating songbirds tested in computer-controlled Emlen funnels use stellar cues for a time-independent compass." Journal of Experimental Biology 204, no. 22 (November 15, 2001): 3855–65. http://dx.doi.org/10.1242/jeb.204.22.3855.
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SUMMARY This paper investigates how young pied flycatchers, Ficedula hypoleuca, and blackcaps, Sylvia atricapilla, interpret and use celestial cues. In order to record these data, we developed a computer-controlled version of the Emlen funnel, which enabled us to make detailed temporal analyses. First, we showed that the birds use a star compass. Then, we tested the birds under a stationary planetarium sky, which simulated the star pattern of the local sky at 02:35 h for 11 consecutive hours of the night, and compared the birds’ directional choices as a function of time with the predictions from five alternative stellar orientation hypotheses. The results supported the hypothesis suggesting that birds use a time-independent star compass based on learned geometrical star configurations to pinpoint the rotational point of the starry sky (north). In contrast, neither hypotheses suggesting that birds use the stars for establishing their global position and then perform true star navigation nor those suggesting the use of a time-compensated star compass were supported.
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Feldmeier-Krause, A., W. Kerzendorf, T. Do, F. Nogueras-Lara, N. Neumayer, C. J. Walcher, A. Seth, et al. "Asymmetric spatial distribution of subsolar metallicity stars in the Milky Way nuclear star cluster." Monthly Notices of the Royal Astronomical Society 494, no. 1 (March 30, 2020): 396–410. http://dx.doi.org/10.1093/mnras/staa703.
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ABSTRACT We present stellar metallicity measurements of more than 600 late-type stars in the central 10 pc of the Galactic Centre. Together with our previously published KMOS data, this data set allows us to investigate, for the first time, spatial variations of the nuclear star cluster’s metallicity distribution. Using the integral-field spectrograph KMOS (VLT), we observed almost half of the area enclosed by the nuclear star cluster’s effective radius. We extract spectra at medium spectral resolution and apply full spectral fitting utilizing the PHOENIX library of synthetic stellar spectra. The stellar metallicities range from [M/H] = −1.25 dex to [M/H] > +0.3 dex, with most of the stars having supersolar metallicity. We are able to measure an anisotropy of the stellar metallicity distribution. In the Galactic north, the portion of subsolar metallicity stars with [M/H] < 0.0 dex is more than twice as high as in the Galactic south. One possible explanation for different fractions of subsolar metallicity stars in different parts of the cluster is a recent merger event. We propose to test this hypothesis with high-resolution spectroscopy and by combining the metallicity information with kinematic data.
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Fariña, Cecilia, Guillermo L. Bosch, and Rodolfo R. Barbá. "A deep dive into NGC 604 with Gemini/NIRI imaging." Proceedings of the International Astronomical Union 5, S266 (August 2009): 391–94. http://dx.doi.org/10.1017/s1743921309991451.
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AbstractThe giant Hii region NGC 604 constitutes a complex and rich population to study in detail many aspects of massive star formation, such as their environments and physical conditions, the evolutionary processes involved, the initial mass function for massive stars and star-formation rates, among many others. Here, we present our first results of a near-infrared study of NGC 604 performed with NIRI images obtained with Gemini North. Based on deep JHK photometry, 164 sources showing infrared excess were detected, pointing to the places where we should look for star-formation processes currently taking place. In addition, the color–color diagram reveals a great number of objects that could be giant/supergiant stars or unresolved, small, tight clusters. An extinction map obtained based on narrow-band images is also shown.
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Duarte Puertas, S., J. Iglesias-Páramo, J. M. Vilchez, L. Drissen, C. Kehrig, and T. Martin. "Searching for intergalactic star forming regions in Stephan’s Quintet with SITELLE." Astronomy & Astrophysics 629 (September 2019): A102. http://dx.doi.org/10.1051/0004-6361/201935686.
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Stephan’s Quintet (SQ), the prototypical compact group of galaxies in the local Universe, has been observed with the imaging Fourier transform spectrometer SITELLE, attached to the Canada-France-Hawaii-Telescope, to perform a deep search for intergalactic star-forming emission. In this paper we present the extended ionised gaseous structures detected and analyse their kinematical properties. The large field of view (11′ × 11′) and the spectral ranges of SITELLE have allowed a thorough study of the entire galaxy system, its interaction history and the main properties of the ionised gas. The observations have revealed complex three-dimensional strands in SQ seen for the first time, as well as the spatially resolved velocity field for a new SQ dwarf galaxy (M 82-like) and the detailed spectral map of NGC 7320c, confirming its AGN nature. A total of 175 SQ Hα emission regions have been found, 22 of which present line profiles with at least two kinematical components. We studied 12 zones and 28 sub-zones in the SQ system in order to define plausible physical spatial connections between its different parts in the light of the kinematical information gathered. In this respect we have found five velocity systems in SQ: (i) v = [5600−5900] km s−1 associated with the new intruder and the southern debris region; (ii) v = [5900−6100] km s−1, associated with the north starburst A and south starburst A and the strands connected to these zones; (iii) v = [6100−6600] km s−1, associated with the strands from the large-scale shock region (LSSR); (iv) v = [6600−6800] km s−1, associated with the young tidal tail, the starburst A (SQA), NGC 7319, and the NGC 7319 north lobe; and (v) v = [6800−7000] km s−1, associated with the strands seen connecting LSSR with SQA. We fail to detect ionised gas emission in the old tail, neither in the vicinity of NGC 7318A nor in NGC 7317, and the connection between NGC 7319 north lobe and SQA cannot be confirmed. Conversely, a clear gaseous bridge has been confirmed both spatially and kinematically between the LSSR zone and the NGC 7319 AGN nucleus. Finally, a larger scale, outer rim winding the NGC 7318B/A system clockwise north-west to south-east has been highlighted in continuum and in Hα. This structure may be reminiscent of a sequence of a previously proposed scenario for SQ a sequence of individual interactions.
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Sturm, Francis J., and Charles Jennings. "Star Evviva Spill: Oiled Waterfowl But no Oil." International Oil Spill Conference Proceedings 2001, no. 1 (March 1, 2001): 191–95. http://dx.doi.org/10.7901/2169-3358-2001-1-191.
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ABSTRACT In January 1999, over 200 oiled waterfowl were recovered from the coastal beaches of South Carolina and North Carolina. A large, multiagency response effort was mounted to collect and rehabilitate these birds, and to identify the source of the damaging oil spill. This was the first time on record that the Oil Spill Liability Trust Fund (OSLTF) was used on the East Coast of the Unite States to clean wildlife in the absence of any known spill. A temporary rehabilitation center was established for the bird rescue and recovery operation under the direction of the U.S. Fish and Wildlife Service (USFWS) and the South Carolina Department of Natural Resources (SCDNR), while the U.S. Coast Guard spearheaded efforts to determine the cause and source of the damaging spill. Representatives from a number of government agencies located up and down the eastern seaboard and Gulf Coast worked together to respond to this wildlife damage and identify the source of the spill: the Star Evviva, which discharged 24,700 gallons of heavy fuel oil approximately 30 miles off the coast of South Carolina. Responding agencies used a unified response and innovative techniques to deal with the unusual challenges presented by this event. This paper summarizes the “lessons learned” in that response effort and attempts to provide useful advice concerning wildlife contingency planning and oil spill investigation and identification.
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Odewahn, S. C. "The Performance of Neural Networks in Astronomical Image Classification." Symposium - International Astronomical Union 161 (1994): 235–41. http://dx.doi.org/10.1017/s0074180900047380.
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The use of neural network pattern recognition techniques in the field of astronomy is reviewed. In assessing the quality of image recognition derived from this method particular attention is given to the problem of star/galaxy discrimination in large digital sky surveys. A two color survey of 9 fields of the first epoch Palomar Sky Survey, centered on the North Galactic Pole, has been performed with the Minnesota Automated Plate Scanner. A set of neural network image classifiers are used to automatically perform star/galaxy discrimination. We assess the efficiency of image classification and sample completeness through comparisons with a variety of independent studies of the NGP area.
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Efendi Samosir, Hasrat. "Opportunities and Challenges of the DPW Crescent Star Party in Elections in North Sumatra." Budapest International Research and Critics Institute (BIRCI-Journal) : Humanities and Social Sciences 1, no. 3 (October 19, 2018): 383–91. http://dx.doi.org/10.33258/birci.v1i3.62.
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In the context of Indonesia where the population is predominantly Muslim (even the largest Muslim country in the world) the views above are very relevant if linked to the political life of Muslims. In the 2009 General Election the UN vote was greatly reduced and could not exceed the 2.5% threshold, so that they could not place their representatives in the DPR RI, in connection with that the UN DPP through the Independent Survey Institute of the University of Indonesia (UI) had done survey to find out the causes, with results: first, the Candidate Figure is unknown or unpopular. Second, party administrators are less well known and not close to the community. Third, programs and issues are not in accordance with the aspirations of the people. Fourth, the image of leaders and administrators is rarely covered by the mass media. Fifth, the performance of legislators and regional heads from the United Nations is not aspiration and less publicized.
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Schmidt, T., R. Neuhäuser, and M. Mugrauer. "Finding orbital motion of sub-stellar companions - the case of TWA 5B." Proceedings of the International Astronomical Union 3, S248 (October 2007): 126–27. http://dx.doi.org/10.1017/s1743921308018851.
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AbstractTWA 5B is a brown dwarf companion of H=12 mag, 2″ off the ~5 mag brighter triple star CoD-33° 7795 (=TWA 5), a member of the TW Hydrae association of T Tauri stars at ~55 pc. This object is the first brown dwarf around a pre-main-sequence star (confirmed by common proper motion) ever found. In the last year we have newly reduced VLT NaCo data originally taken in 2003 and combined it with all the available astrometric data of the system to investigate possibly detectable orbital motion of the system. Indeed we were able to find linear orbital motion of the system combining data from HST, VLT and Gemini-North.
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Bunker, Andrew, Michelle Doherty, Rob Sharp, Ian Parry, Gavin Dalton, and Ian Lewis. "Measuring the Star Formation Rate of the Universe at z ~ 1 from Hα with Multi-Object Near-Infrared Spectroscopy." Proceedings of the International Astronomical Union 2, S235 (August 2006): 394. http://dx.doi.org/10.1017/s1743921306010271.
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AbstractWe have demonstrated the first near-infrared multi-object spectrograph, CIRPASS, on the 4.2-m William Herschel Telescope (WHT) and the 3.9-m Anglo-Australian Telescope. We have conducted an Hα survey of 38 0.77 < z < 1 galaxies over ~100 arcmin2 of the Hubble Deep Field North and Flanking Fields, to determine star formation rates (SFRs) using CIRPASS on the WHT. This represents the first successful application of this technique to observing high redshift galaxies (Doherty et al. 2004). Stacking the spectra in the rest-frame, we find a lower limit (uncorrected for dust reddening) on the star formation rate density at redshift z = 1 of 0.04 M⊙ yr−1 Mpc−3 (Doherty et al. 2006). This implies rapid evolution in the star formation rate density from z = 0 to z = 1 which is proportional to (1 + z)3.1. We intend to extend our work with FMOS on Subaru as the evolSMURF project (the Evolution of Star-formation and Metallicity in the Universe at high Redshift with FMOS). This will represent nearly two orders-of-magnitude improvement on previous work, and for the first time will provide a sample of sufficient size to measure accurately the Hα luminosity function, and so determine the global star formation rate using the same indicator as used in local surveys. Using [O II]3727 Å, Hβ, [O III] 5007 Å and Hα redshifted into the z, J & H bands, we can chart the star formation history over 70% of the age of the Universe, affording complete coverage up to z = 1.6 with the same well-understood diagnostics. The line ratios will also allow the extinction and metallicity to be measured at z>1. This will resolve one of the long-standing puzzles in extragalactic astrophysics – the true evolution of the Madau-Lilly diagram of star formation density.
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Deshev, Boris, Christopher Haines, Ho Seong Hwang, Alexis Finoguenov, Rhys Taylor, Ivana Orlitova, Maret Einasto, and Bodo Ziegler. "Mapping the working of environmental effects in A963." Astronomy & Astrophysics 638 (June 2020): A126. http://dx.doi.org/10.1051/0004-6361/202037803.
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Aims. We qualitatively assess and map the relative contribution of pre-processing and cluster related processes to the build-up of A963, a massive cluster at z = 0.2 showing an unusually high fraction of star forming galaxies in its interior. Methods. We use Voronoi binning of positions of cluster members on the plane of the sky in order to map the 2D variations of galaxy properties in the centre and infall region of A963. We map four galaxy parameters (fraction of star forming galaxies, specific star formation rate, H I deficiency and age of the stellar population) based on full SED fitting, 21 cm imaging and optical spectroscopy. Results. We find an extended region dominated by passive galaxies along a north–south axis crossing the cluster centre, possibly associated with known filaments of the large-scale structure. There are signs that the passive galaxies in this region were quenched long before their arrival in the vicinity of the cluster. Contrary to that, to the east and west of the cluster centre lie regions of recent accretion dominated by gas rich, actively star forming galaxies not associated with any substructure or filament. The few passive galaxies in this region appear to be recently quenched, and some gas rich galaxies show signs of ongoing ram-pressure stripping. We report the first tentative observations at 21 cm of ongoing ram-pressure stripping at z = 0.2, as well as observed inflow of low-entropy gas into the cluster along filaments of the large-scale structure. Conclusions. The observed galaxy content of A963 is a result of strongly anisotropic accretion of galaxies with different properties. Gas rich, star forming galaxies are being accreted from the east and west of the cluster and these galaxies are being quenched at r < R200, likely by ram-pressure stripping. The bulk of the accretion onto the cluster, containing multiple groups, happens along the north–south axis and brings mostly passive galaxies, likely quenched before entering A963.
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Baumiller, Tomasz K., and R. Ewan Fordyce. "Rautangaroa, a new genus of feather star (Echinodermata, Crinoidea) from the Oligocene of New Zealand." Journal of Paleontology 92, no. 5 (May 25, 2018): 872–82. http://dx.doi.org/10.1017/jpa.2018.17.
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AbstractWe describe a nearly complete, and thus extremely rare, feather star (Crinoidea, Comatulida) from Oligocene strata of North Otago/South Canterbury, New Zealand. A detailed analysis of this specimen, as well as newly recovered material and previously described fragmentary remains from nearby contemporaneous sedimentary units, in addition to relevant historical specimens, lead us to conclude that it cannot be placed in any currently established genus. A new genus,Rautangaroa,is proposed to accommodate it.This intact specimen ofRautangaroa aotearoa(Eagle, 2007), provides rare data on the morphology of arms and cirri. It represents the first example of arm autotomy and regeneration in a fossil feather star and thus has bearing on the importance of predation to the evolutionary history of this group.UUID:http://zoobank.org/c050dafd-93ba-4334-b11b-59209aabb588
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Zinnecker, Hans, Alain Chelli, Luis Carrasco, Irene Cruz-Gonzales, and Christian Perrier. "GSS 31: Another T Tauri star with an infrared companion." Symposium - International Astronomical Union 122 (1987): 117–18. http://dx.doi.org/10.1017/s0074180900156165.
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Using a rapid slit scan technique in the infrared (JHKL), the source GSS 31 (alias EL 22 or Do-Ar 24E), a T Tauri star in the Ophiuchus dark cloud, was discovered to be double at a projected separation of 1.“95±0.”10 (i.e. 320 AU). The position angle is almost exactly north-south. This is the second discovery of its kind, and the first in the southern hemisphere, the only previous case known being T Tauri itself (Dyck et al. 1982, Schwartz et al. 1984). The important point is that we were able to secure infrared photometry separately for both components while for T Tau the separation into two components was model-dependent due to their small separation (0.6). IR-photometry for the joint system GSS 31 had previously been obtained by Grasdalen, Strom & Strom (1973) and Elias (1978), while Chini (1981) obtained UBVRI photometry.
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Nayak, P. K., A. Subramaniam, S. Choudhury, and Ram Sagar. "Star clusters in the Magellanic Clouds." Astronomy & Astrophysics 616 (August 2018): A187. http://dx.doi.org/10.1051/0004-6361/201732227.
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Aims. We aim to estimate the age and reddening parameters of already identified star clusters within the Small Magellanic Cloud (SMC) in a consistent way using available photometric data, classify them based on their mass and strength, and study their spatiotemporal distribution. Methods. We have used a semi-automated quantitative method, developed in the first paper of this series (Paper I), to estimate the cluster parameters using the V and I band photometric data from the Optical Gravitational Lensing Experiment (OGLE) III survey. Results. We estimated parameters of 179 star clusters (17 are newly parameterised) and classified them into four groups. We present an online catalogue of parameters as well as cleaned and isochrone-fitted colour magnitude diagrams of 179 clusters. We compiled age information of 468 clusters by combining previous studies with our catalogue, to study their spatio-temporal distribution. Most of the clusters located in the southern part of the SMC are in the age range 600 Myr–1.25 Gyr, whereas, the clusters younger than 100 Myr are mostly found in the northern SMC, with the central SMC showing continuous cluster formation. The peak of the cluster age distribution is identified at 130 ± 35 Myr, very similar to the Large Magellanic Cloud (LMC) in Paper I. Conclusions. We suggest that the burst of cluster formation at 130 Myr is due to the most recent LMC-SMC interaction. 90% of the studied sample is found to have mass < 1700 M⊙, suggesting that the SMC is dominated by low mass clusters. There is tentative evidence for compact clusters in the LMC when compared to those in the Galaxy and the SMC. A progressive shifting of cluster location from the south to north of the SMC is identified in last ~600 Myr. The details of spatio-temporal distribution of clusters presented in two videos as part of this study can be used as a tool to constrain details of the recent LMC-SMC interactions.
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Watson, Linda C., Paul Martini, Kalliopi M. Dasyra, Misty C. Bentz, Laura Ferrarese, Bradley M. Peterson, Richard W. Pogge, and Linda J. Tacconi. "First Stellar Velocity Dispersion Measurement of a Luminous Quasar Host with Gemini North Laser Guide Star Adaptive Optics." Astrophysical Journal 682, no. 1 (July 3, 2008): L21—L24. http://dx.doi.org/10.1086/591026.
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Venuti, L., L. Prisinzano, G. G. Sacco, E. Flaccomio, R. Bonito, F. Damiani, G. Micela, et al. "The Gaia-ESO Survey and CSI 2264: Substructures, disks, and sequential star formation in the young open cluster NGC 2264." Astronomy & Astrophysics 609 (December 22, 2017): A10. http://dx.doi.org/10.1051/0004-6361/201731103.
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Context. Reconstructing the structure and history of young clusters is pivotal to understanding the mechanisms and timescales of early stellar evolution and planet formation. Recent studies suggest that star clusters often exhibit a hierarchical structure, possibly resulting from several star formation episodes occurring sequentially rather than a monolithic cloud collapse. Aims. We aim to explore the structure of the open cluster and star-forming region NGC 2264 (~3 Myr), which is one of the youngest, richest and most accessible star clusters in the local spiral arm of our Galaxy; we link the spatial distribution of cluster members to other stellar properties such as age and evolutionary stage to probe the star formation history within the region. Methods. We combined spectroscopic data obtained as part of the Gaia-ESO Survey (GES) with multi-wavelength photometric data from the Coordinated Synoptic Investigation of NGC 2264 (CSI 2264) campaign. We examined a sample of 655 cluster members, with masses between 0.2 and 1.8 M⊙ and including both disk-bearing and disk-free young stars. We used Teff estimates from GES and g,r,i photometry from CSI 2264 to derive individual extinction and stellar parameters. Results. We find a significant age spread of 4–5 Myr among cluster members. Disk-bearing objects are statistically associated with younger isochronal ages than disk-free sources. The cluster has a hierarchical structure, with two main blocks along its latitudinal extension. The northern half develops around the O-type binary star S Mon; the southern half, close to the tip of the Cone Nebula, contains the most embedded regions of NGC 2264, populated mainly by objects with disks and ongoing accretion. The median ages of objects at different locations within the cluster, and the spatial distribution of disked and non-disked sources, suggest that star formation began in the north of the cluster, over 5 Myr ago, and was ignited in its southern region a few Myr later. Star formation is likely still ongoing in the most embedded regions of the cluster, while the outer regions host a widespread population of more evolved objects; these may be the result of an earlier star formation episode followed by outward migration on timescales of a few Myr. We find a detectable lag between the typical age of disk-bearing objects and that of accreting objects in the inner regions of NGC 2264: the first tend to be older than the second, but younger than disk-free sources at similar locations within the cluster. This supports earlier findings that the characteristic timescales of disk accretion are shorter than those of disk dispersal, and smaller than the average age of NGC 2264 (i.e., ≲3 Myr). At the same time, we note that disks in the north of the cluster tend to be shorter-lived (~2.5 Myr) than elsewhere; this may reflect the impact of massive stars within the region (notably S Mon), that trigger rapid disk dispersal. Conclusions. Our results, consistent with earlier studies on NGC 2264 and other young clusters, support the idea of a star formation process that takes place sequentially over a prolonged span in a given region. A complete understanding of the dynamics of formation and evolution of star clusters requires accurate astrometric and kinematic characterization of its population; significant advance in this field is foreseen in the upcoming years thanks to the ongoing Gaia mission, coupled with extensive ground-based surveys like GES.
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Dunlop, M. W., M. G. G. T. Taylor, J. A. Davies, C. J. Owen, F. Pitout, A. N. Fazakerley, Z. Pu, et al. "Coordinated Cluster/Double Star observations of dayside reconnection signatures." Annales Geophysicae 23, no. 8 (November 8, 2005): 2867–75. http://dx.doi.org/10.5194/angeo-23-2867-2005.
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Abstract. The recent launch of the equatorial spacecraft of the Double Star mission, TC-1, has provided an unprecedented opportunity to monitor the southern hemisphere dayside magnetopause boundary layer in conjunction with northern hemisphere observations by the quartet of Cluster spacecraft. We present first results of one such situation where, on 6 April 2004, both Cluster and the Double Star TC-1 spacecraft were on outbound transits through the dawnside magnetosphere. The observations are consistent with ongoing reconnection on the dayside magnetopause, resulting in a series of flux transfer events (FTEs) seen both at Cluster and TC-1, which appear to lie north and south of the reconnection line, respectively. In fact, the observed polarity and motion of each FTE signature advocates the existence of an active reconnection region consistently located between the positions of Cluster and TC-1, with Cluster observing northward moving FTEs with +/- polarity, whereas TC-1 sees -/+ polarity FTEs. This assertion is further supported by the application of a model designed to track flux tube motion for the prevailing interplanetary conditions. The results from this model show, in addition, that the low-latitude FTE dynamics are sensitive to changes in convected upstream conditions. In particular, changing the interplanetary magnetic field (IMF) clock angle in the model suggests that TC-1 should miss the resulting FTEs more often than Cluster and this is borne out by the observations.
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Freed, Melanie, Laird M. Close, and Nick Siegler. "Discovery of a Tight Brown Dwarf Companion to the Low Mass Star LHS 2397a." Symposium - International Astronomical Union 211 (2003): 261–64. http://dx.doi.org/10.1017/s0074180900210693.
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Using the adaptive optics system, Hōkūpa'a, at Gemini-North, we have directly imaged a companion around the UKIRT faint standard M8 star, LHS 2397a (FS 129) at a separation of 2.96 AU. Near-Infrared photometry obtained on the companion has shown it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to be an M8. We also derive a substellar mass of the companion of 0.068M⊙, although masses in the range (0.061 – 0.069) are possible, and the primary mass as 0.090M⊙ (0.089 – 0.094). Reanalysis of archival imaging from HST has confirmed the secondary as a common proper motion object. This binary represents the first clear example of a brown dwarf companion within 4 AU of a low mass star, and should be the first L7.5 to have a dynamical mass. As part of a larger survey of M8-M9 stars, this object may indicate that there is no “brown dwarf desert” around low mass primaries.
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Lumbreras-Calle, A., J. Méndez-Abreu, and C. Muñoz-Tuñón. "The stellar host in star-forming low-mass galaxies: Evidence for two classes." Astronomy & Astrophysics 632 (November 21, 2019): A15. http://dx.doi.org/10.1051/0004-6361/201935288.
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Context. The morphological evolution of star-forming galaxies provides important clues to understand their physical properties, as well as the triggering and quenching mechanisms of star formation. Aims. We analyze the morphology of galaxies hosting star-forming events at low redshift (z < 0.36). We aim at connecting morphology and star-formation properties of low-mass galaxies (median stellar mass ∼108.5 M⊙) beyond the local Universe. Methods. We use a sample of mediumband selected star-forming galaxies from the GOODS-North field. Hα images for the sample are created combining both spectral energy distribution fits and HST data. Using them, we mask the star forming regions to obtain an unbiased two-dimensional model of the light distribution of the host galaxies. For this purpose we use PHI, a new Bayesian photometric decomposition code. We applied it independently to 7 HST bands, from the ultraviolet to the near-infrared, assuming a Sérsic surface brightness model. Results. Star-forming galaxy hosts show low Sérsic index (with median n ∼ 0.9), as well as small sizes (median Re ∼ 1.6 kpc), and negligible change of the parameters with wavelength (except for the axis ratio, which grows with wavelength in 46% of the sample). Using a clustering algorithm, we find two different classes of star-forming galaxies: A more compact, redder, and high-n (class A) and a more extended, bluer and lower-n one (class B). This separation holds across all seven bands analyzed. In addition, we find evidence that the first class is more spheroidal-like (according to the distribution of observed axis ratios). We compute the color gradients of the host galaxies finding that 48% of the objects where the analysis could be performed show negative gradients, and only in 5% they are positive. Conclusions. The host component of low-mass star-forming galaxies at z < 0.36 separates into two different classes, similar to what has been found for their higher mass counterparts. The results are consistent with an evolution from class B to class A. Several mechanisms from the literature, like minor and major mergers, and violent disk instability, can explain the physical process behind the likely transition between the classes.
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Asanok, K., B. Hutawarakorn Kramer, S. Etoka, M. Gray, A. M. S. Richards, N. Gasiprong, and N. Naochang. "Full polarization analysis of OH masers at 18-cm toward W49 A star forming region." Proceedings of the International Astronomical Union 13, S336 (September 2017): 309–10. http://dx.doi.org/10.1017/s1743921317011498.
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AbstractW49 A is a star-forming region (SFR) found in the constellation of Aquila. It contains 3 active regions: W49 North (W49 N), W49 South West (W49 SW) and W49 South (W49 S). We present preliminary results from two epochs (e-)MERLIN observations of all ground-state OH masers towards the star-forming region (SFR) complex W49 A. The first epoch of observations was done in full-polarization mode with MERLIN in 2005 while the second epoch was obtained only in dual circular polarization during the test observations of the upgraded e-MERLIN in 2013. The overall maser spatial distributions in both epochs are in good agreement. We found several new high velocity maser features up to +34 km s−1 and −28 km s−1. The magnetic field strengths are between 1.1 to 10.8 mG. All three sources show evidence of magnetic field reversal.
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Watson, Sarah K., Richard J. Davis, and Peredur M. Williams. "MERLIN observations of WR 147 (WN8(h)+B0.5V)." Symposium - International Astronomical Union 193 (1999): 396–97. http://dx.doi.org/10.1017/s0074180900205913.
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WR147 was first discovered to be a strong radio, X-ray and infra-red emission source by Caillault et al. (1985). It was classified as a WN8 type star with a very large mass loss rate and unusual radio emission (α < 0) for a thermal source. This unusual behaviour was explained by MERLIN (Moran et al. 1989) and VLA (Churchwell et al. 1992) observations in which it was resolved into two components: a ‘thermal’ source associated with the Wolf-Rayet star and a non-thermal component ∼ 600 mas to the north. Churchwell et al. showed that the southern component had the expected spectral index of α ≃ 0.6 for free-free emission from a stellar wind. They also showed that the northern component had a spectral index of α ≃ −0.5 and was therefore a non-thermal source, now thought to be due to a colliding wind region.
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Achmad, M. Janib, Alim Isnansetyo, Noer Kasanah, Ustadi Ustadi, and Kamiso Kamiso. "IMMUNOSTIMULATORY EFFECT OF FATTY ACID FROM STAR FISH (ACANTHASTER PLANCI) ON LYMPHOCYTE PROLIFERATION IN-VITRO." Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 9, no. 3 (December 12, 2014): 107. http://dx.doi.org/10.15578/squalen.v9i3.109.
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The aims of this study were to investigate lymphocyte proliferation activity and to identify chemical constituents of active fractions of star fish Acanthaster planci. A. planci was collected from Ternate Island, North Moluccas, extracted with distilled methanol and water, partitioned with gradient chloroform-hexane-methanol-water and fractionated in column chromatography using silica gel and hexane-ethyl acetate-methanol. The active compound had been purified by Thin Layer Chromatography (TLC) and identified by Gas Chromatography-Mass Spectrometry (GC-MS). The lymphocyte proliferation activity was measured based on % Stimulation Index (SI) from sample absorbency and control absorbency. The result showed that the 3 fractions of hexane fraction exhibited lymphocyte proliferation activity. Fraction 1 was able to increase lymphocyte proliferation at 48 hours and 72 hours by 55% (80 µl/ml) and 88% (160 µl/ml) increase, and fraction 2 had 77% (160 µl/ml) and 86% (640 µl/ml) increase. Meanwhile, fraction 3 had 75% (640 µl/ml) and 89% (640 µl/ml) increase. Metabolite analysis of active fraction using GC-MS yielded a number of chemical constituents that was dominated by fatty acid. The study concluded that star fish A. planci from Ternate Island has a potential source of immunostimulator.
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Sareyan, J. P., J. Chauville, D. Briot, S. J. Adelman, M. Alvarez, I. Balega, Y. Balega, et al. "First results of an international multisite multitechnique campaign on o micron And." Symposium - International Astronomical Union 162 (1994): 282–83. http://dx.doi.org/10.1017/s007418090021509x.
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Omicron Andromedae is a multiple system of at least four stars: a B ↔Be star (component A), a spectroscopic binary (components B1–B2) and a close companion (component a). According to several studies (see Hill et al. 1988, 1989): -the distance between A and the B1–B2 system decreased from 0.39″ in 1975 to 0.25″ in 1987 (McAlister and Hartkopf 1988)-the few previous speckle measurements of component a have shown the possibility of a 3.7 years orbit around A, according to the 1975 to 1984 observations (mean distance 0.05″). The calculations with this 3.7 yr orbit lead to the prediction of a maximum distance of 0.77″ at 1992.738, i.e. at the end of september 1992, with a North-South orientation.
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Lawley, Jonathan W., Adriana Carvalhal Fonseca, Edson Faria Júnior, and Alberto Lindner. "Occurrence of the non-indigenous brittle star Ophiothela cf. mirabilis Verrill, 1867 (Echinodermata, Ophiuroidea) in natural and anthropogenic habitats off Santa Catarina, Brazil." Check List 14, no. 2 (April 13, 2018): 453–59. http://dx.doi.org/10.15560/14.2.453.
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The brittle star Ophiothela mirabilis, thought to be confined to Pacific waters, was first observed in the Atlantic in 2000. Since then, it has expanded its range north to Trinidad and Tobago and south to Paraná, Brazil. By monitoring the coast of Santa Catarina, Brazil, with both recruitment plates in harbors and SCUBA diving, we were able to observe specimens of Ophiothela mirabilis in both natural and anthropogenic habitats. This presents a range extension of ~80 km south and emphasizes the importance of anthropogenic means for their spread and establishment.
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Maryeva, Olga V., Gloria Koenigsberger, Sergey V. Karpov, Tatiana A. Lozinskaya, Oleg V. Egorov, Corinne Rossi, Massimo Calabresi, and Roberto F. Viotti. "Asymmetrical nebula of the M33 variable GR290 (WR/LBV)." Astronomy & Astrophysics 635 (March 2020): A201. http://dx.doi.org/10.1051/0004-6361/201936840.
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Context. GR 290 (M 33 V0532 = Romano’s star) is a luminous M 33 object undergoing photometric variability typical for luminous blue variable stars. It lies inside the Wolf-Rayet region in the Hertzsprung-Russell diagram and possesses a WN8-type spectrum at the light minima. Analysis of Gran Telescopio Canarias spectra obtained in 2016 led to the conclusion that it is surrounded by an unresolved H II region formed mostly of ejected material from the central star and revealed the presence of a second, more extended asymmetrical emission region. Aims. The aim of this paper is to further explore the structure of the nearby environment of GR 290. Methods. Long-slit spectra of GR 290 were obtained with three slit orientations in the visual and red spectral regions. The emission-line distribution for each slit was analyzed. Results. We confirm the presence of an asymmetric H II region that extends ~50 pc to the south; ~30 pc to the north, and southeast; ~20 pc to the east and northwest; and ~10 pc to the west. We also present the first spectrum to be acquired of a star belonging to the neighboring OB 88 association, J013501.87+304157.3, which we classify as a B-type supergiant with a possible binary companion.
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Kreysing, H. C., C. Diesch, J. Zweigle, R. Staubert, and M. Grewing. "Extended X-Ray Emission from Planetary Nebulae." Symposium - International Astronomical Union 155 (1993): 197. http://dx.doi.org/10.1017/s0074180900170597.
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We present first results from the ROSAT All Sky Survey on X-ray emission of planetary nebulae (PNe). For the first time extended X-ray emission from PNe was detected. This is the case for NGC 6543, NGC 6853, A 12, NGC 4361 (and LoTr 5). X-ray emission compatible with a point source was detected from BD+30°3639, however, the spectral distribution of the X-ray photons is leading to temperatures beyond 2 106 K. Thus in all cases, with the possible exception of LoTr 5, the central star of the PNe can be excluded as the main source of the observed X-ray emission. X-ray images and ROSAT spectra for all detected PNe are presented. The best observed PN in X-ray emission is NGC 6543. Due to the close vicinity to the north ecliptic pole, this object was regularly observed, every 90 minutes during the whole half year of the ROSAT All Sky Survey, resulting in 41 ksec of integration time. In addition NGC 6543 was observed in a 50 ksec pointed observation to the north ecliptic pole, taken in June 1990 during the calibration phase (Kreysing et al. 1992). A comparison of the semi-ring-like distribution of the X-ray emission of NGC 6543 with optical CCD-images shows, that most of the X-ray emission seems to originate from the boundary region between the nebula and the halo. Neither the central star nor the hot wind from the central star wind is the main source of the X-ray emission, as proposed by the interacting stellar wind model (Kwok 1982). An alternative model employing a possible coronal heating mechanism has been discussed by Kreysing (1992); accoustic waves, travelling outward from the nebula, encounter a sudden density decline at the boundary to the halo. As a consequence the waves degenerate into shock waves, dissipating their energy in a thin region of only some 1015 cm into the ambient medium.
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White, Craig Howard. "Natural Law and National Science: The “Star of Empire” in Manifest Destiny and the American Observatory Movement." Prospects 20 (October 1995): 119–60. http://dx.doi.org/10.1017/s0361233300006037.
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From its revolution based on Newtonian physics to its Star-Spangled Banner on the Moon, the United States of America shares with astronomy a worldview of infinite expansion. As above, so below: in space, myriad galaxies multiply the stars; on earth, cities of light interminably sprawl with people and production. This cosmology of growth, which first materialized in the scientific revolution and conquest of America during the European Renaissance, reemerges in the “American Renaissance” of the 1840s and 1850s when the American Observatory Movement and Manifest Destiny declare expansion a natural law for the heavens and North America.
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Merlin, E., F. Fortuni, M. Torelli, P. Santini, M. Castellano, A. Fontana, A. Grazian, L. Pentericci, S. Pilo, and K. B. Schmidt. "Red and dead CANDELS: massive passive galaxies at the dawn of the Universe." Monthly Notices of the Royal Astronomical Society 490, no. 3 (September 19, 2019): 3309–28. http://dx.doi.org/10.1093/mnras/stz2615.
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ABSTRACT We search the five CANDELS fields (COSMOS, EGS, GOODS-North, GOODS-South, and UDS) for passively evolving a.k.a. ‘red and dead’ massive galaxies in the first 2 Gyr after the big bang, integrating and updating the work on GOODS-South presented in a previous paper. We perform SED-fitting on photometric data, with top-hat star-formation histories to model an early and abrupt quenching, and using a probabilistic approach to select only robust candidates. Using libraries without (with) spectral lines emission, starting from a total of more than 20 000 z > 3 sources we end up with 102 (40) candidates, including one at z = 6.7. This implies a minimal number density of 1.73 ± 0.17 × 10−5 (6.69 ± 1.08 × 10−6) Mpc−3 for 3 < z < 5; applying a correction factor to account for incompleteness yields 2.30 ± 0.20 × 10−5. We compare these values with those from five recent hydrodynamical cosmological simulations, finding a reasonable agreement at z < 4; tensions arise at earlier epochs. Finally, we use the star-formation histories from the best-fitting models to estimate the contribution of the high-redshift passive galaxies to the global star formation rate density during their phase of activity, finding that they account for ∼5–10 per cent of the total star formation at 3 < z < 8, despite being only $\sim 0.5{{\ \rm per\ cent}}$ of the total in number. The resulting picture is that early and strong star formation activity, building massive galaxies on short time-scales and followed by a quick and abrupt quenching, is a rare but crucial phenomenon in the early Universe: the evolution of the cosmos must be heavily influenced by the short but powerful activity of these pristine monsters.
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Trenkler, I. V. "The aquaculture of Acipenseriformes. Part 6. Northern and South America." Rybovodstvo i rybnoe hozjajstvo (Fish Breeding and Fisheries), no. 10 (October 1, 2020): 68–79. http://dx.doi.org/10.33920/sel-09-2010-07.
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The history and contemporary state of global aquaculture of sturgeons and paddlefish are reviewed. The paddlefish Polyodon spathula became first object of cultivation of Acipenseriformes in USA. The paddlefish has high rate of growth in ponds using natural feeds, mature females can produce about 15% of their body weight in roe similar to eggs of star sturgeon Acipenser stellatus. Some liabilities include juveniles vulnerable to bird predation, poor tolerance to high densities, low oxygen and handling stress, waiting period of at least 7 years before females produce eggs. The paddlefish farming is carried out mainly in Kentucky, Indiana, Missouri and Alabama in polyculture with canal catfish Ictalurus punctatus or freshwater shrimp Macrobrachium rosenbergii. The most important object of North-American sturgeon breeding is white sturgeon Acipenser transmontanus, the biggest and fast-growing species of Acipenser genera. The largest commercial sturgeon farms are located in California, Idaho and Florida. A research program on biotechnology of white sturgeon farming has been initiated by the University of California at Davis in December 1979. The first successful artificial propagation of white sturgeon from Sacramento River was carried out in 1980, the first hatchery females matured in 1994. The hatchery progeny of Snake River white sturgeon was received in 1988, the first females matured in 2000. The first caviar was processed only after maturation of second generation. In Florida and North Carolina farmers used for cultivation small number of Russian sturgeon A. gueldenstaedti, Siberian sturgeon A. baeri, sterlet A. ruthenus, beluga Huso huso and star sturgeon A. stellatus. The total annual volume of sturgeon farming in USA was equal to 1285 tons (1166 MT). In Canada the only object of sturgeon farming is white sturgeon with annual production near 2 tons of caviar. In South America Uruguay has developed sturgeon culture with one large farm created in 1994 using help of Russian specialists.
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Minier, V., N. Peretto, S. N. Longmore, M. G. Burton, R. Cesaroni, C. Goddi, M. R. Pestalozzi, and Ph André. "Anatomy of the S255–S257 complex – triggered high-mass star formation." Proceedings of the International Astronomical Union 2, S237 (August 2006): 160–64. http://dx.doi.org/10.1017/s1743921307001391.
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AbstractWe present a multi-wavelength (NIR to radio) and multi-scale (1 AU to 10 pc) study of the S255–S257 complex of young high-mass (proto)stars. The complex consists of two evolved HII regions and a molecular gas filament in which new generations of high mass stars form. Four distinct regions are identified within this dusty filament: a young NIR/optical source cluster, a massive protostar binary, a (sub)millimetre continuum and molecular clump in global collapse and a reservoir of cold gas. Interestingly, the massive binary protostellar system is detected through methanol maser and mid-IR emission at the interface between the NIR cluster and the cold gas filament. The collapsing clump is located to the north of the NIR cluster and hosts a young high-mass star associated with an outflow that is observed in mid-IR, methanol maser and radio emission. We interpret this anatomy as the possible result of triggered star formation, starting with the formation of two HII regions, followed by the compression of a molecular gas filament in which a first generation of high-mass stars forms (the NIR cluster), which then triggers the formation of high mass protostars in its near environment (the massive protostellar binary). The global collapse of the northern clump might be due to both the expansion of the HII regions that squashes the filament. In conclusion, we witness the formation of four generations of clusters of high-mass stars in S255–S257.
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Das, Kaustav K., Catherine Zucker, Joshua S. Speagle, Alyssa Goodman, Gregory M. Green, and João Alves. "Constraining the distance to the North Polar Spur with Gaia DR2." Monthly Notices of the Royal Astronomical Society 498, no. 4 (September 7, 2020): 5863–72. http://dx.doi.org/10.1093/mnras/staa2702.
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ABSTRACT The North Polar Spur (NPS) is one of the largest structures observed in the Milky Way in both the radio and soft X-rays. While several predictions have been made regarding the origin of the NPS, modelling the structure is difficult without precise distance constraints. In this paper, we determine accurate distances to the southern terminus of the NPS and towards latitudes ranging up to 55°. First, we fit for the distance and extinction to stars towards the NPS using optical and near-infrared photometry and Gaia Data Release 2 astrometry. We model these per-star distance–extinction estimates as being caused by dust screens at unknown distances, which we fit for using a nested sampling algorithm. We then compare the extinction to the Spur derived from our 3D dust modelling with integrated independent measures from XMM–Newton X-ray absorption and H i column density measures. We find that we can account for nearly 100 per cent of the total column density of the NPS as lying within 140 pc for latitudes >26° and within 700 pc for latitudes <11°. Based on the results, we conclude that the NPS is not associated with the Galactic Centre or the Fermi bubbles. Instead, it is likely associated, especially at higher latitudes, with the Scorpius–Centaurus association.
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McGregor, Peter J., Michael Dopita, Peter Wood, and Michael G. Burton. "Science with NIFS, Australia's First Gemini Instrument." Publications of the Astronomical Society of Australia 18, no. 1 (2001): 41–57. http://dx.doi.org/10.1071/as01007.
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AbstractThe Near-infrared Integral Field Spectrograph (NIFS) will beAustralia’s first Gemini instrument. NIFS is a near-infrared, imaging spectrograph that will be used with the ALTAIR facility adaptive optics system on Gemini North to perform near-diffraction-limited imaging spectroscopy over a 3·0″ × 3·0″ field of view with 0·1″ wide slitlets and a spectral resolving power of ˜5300. NIFS will operate in the wavelength range from 0·94–2·50 µm where ALTAIR delivers its greatest gains. Its primary purpose is to study moderate-surface-brightness structures around discrete objects that are revealed at high spatial resolution by ALTAIR. NIFS will address a wide range of science from studies of Galactic star formation and the Galactic centre to the nature of disk galaxies at z ˜ 1. Studies of the demographics of massive black holes in galactic nuclei and studies of the excitation conditions in the inner narrow-line regions of Seyfert galaxies have been identified as two core NIFS programs. These and other science drivers for NIFS are discussed.
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Hofmann, K. H., T. Blöcker, G. Weigelt, and Y. Balega. "A Multi-Wavelength Study of the Oxygen-Rich AGB Star CIT 3: Bispectrum speckle interferometry and dust-shell modelling." Symposium - International Astronomical Union 209 (2003): 121. http://dx.doi.org/10.1017/s0074180900208267.
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CIT 3 is an oxygen-rich long-period variable evolving along the Asymptotic Giant Branch and is one of the most extreme infrared AGB objects. Due to substantial mass loss it is surrounded by an optically thick dust shell which absorbs almost all visible light radiated by the star and finally re-emits it in the infrared regime. We present the first near infrared bispectrum speckle-interferometry observations of CIT 3 in the J-, H-, and K′-band (resolution: 48 mas, 56 mas, and 73 mas). The interferograms were obtained with the Russian SAO 6 m telescope. While CIT 3 appears almost spherically symmetric in the H- and K′-band it is clearly elongated in the J-band along a symmetry axis of position angle −28°. Two structures can be identified: a compact elliptical core (eccentricity ~0.8) and a fainter north-western fan-like structure (full opening angle ~ 40°). The development of such asphericities close to the central star suggests that CIT 3 is in the very end of its AGB evolution or even in transition to the proto-planetary nebula phase where most objects are observed in axisymmetric geometry.
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Johnson, Dianne. "Interpretations of the Pleiades in Australian Aboriginal astronomies." Proceedings of the International Astronomical Union 7, S278 (January 2011): 291–97. http://dx.doi.org/10.1017/s1743921311012725.
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AbstractAs there are so many Australian Aboriginal and Torres Strait astronomies and cosmologies, commonalities are unusual. However one of the ‘things belonging to the sky’ that seems common to all groups across the continent is the open star cluster of the Pleiades. Yet interpretations of this cluster vary. So far I have tentatively identified four different cultural areas, the first being most of mainland Australia; the second being the islands south of mainland Australia known as Tasmania; the third being the cultural area of north-eastern Arnhem Land; and the fourth being the cultural area of the Torres Strait Islands. Within these areas, versions of the stories vary as contemporary circumstances change.
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Points, Sean, You-Hua Chu, Sungeun Kim, Robert Gruendl, R. Chris Smith, Steve Snowden, and Wolfgang Brandner. "The Kinematic Structure of the Supergiant Shell LMC 2." Symposium - International Astronomical Union 190 (1999): 156–57. http://dx.doi.org/10.1017/s0074180900117747.
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LMC2 was one of the first supergiant shells in the Large Magellanic Cloud (LMC) to be identified, based on the detection of long, curved Hα filaments extending over 900 pc (Goudis & Meaburn 1978). LMC 2 is located to the east of the active star formation region south of 30 Doradus. LMC 2 is a spectacular supergiant shell in the LMC, having the most coherent filamentary structure and the highest X-ray surface brightness. As shown in Fig. 1, the diffuse X-ray emission from LMC 2 is bounded by the Hα filaments in the north and east. A bright X-ray arc is seen in the southwest quadrant, extending from N 158 and N 159.
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Gottschalk, Peter. "Three Tales of Three Houses." Journal of Asian Studies 73, no. 2 (May 2014): 301–4. http://dx.doi.org/10.1017/s0021911814000436.
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The house has stood empty since Partition. Its Muslim family abandoned their Bihari village in India for a new life in West Pakistan, 1,300 kilometers distant. Unlike most other homes left behind by emigrants, this one's doors still open to its owner's keys, since his brothers remained in their homes nearby. One of those brothers follows invitations across north India preaching the Tablighi Islamic revival. In conversation, he demonstrates little interest in the religious traditions of the Hindu majority of his large village. Two decades ago, his son, Farhad, opened one of the first private schools in the area, anticipating the surging demand for education that has overtaken India. Some of the first classrooms built had brick walls pierced by concrete screens decoratively depicting a Quran, crescent moon, and star. Most of the school's students and many of its teachers are Hindu.
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ŠIMUNOVIĆ-BEŠLIN, BILЈANA. "FACULTY OF LAW IN SUBOTICA – “NORTHERN STAR” OF HIGHER EDUCATION IN THE KINGDOM OF YUGOSLAVIA." ИСТРАЖИВАЊА, no. 29 (December 26, 2018): 143–62. http://dx.doi.org/10.19090/i.2018.29.143-162.
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The paper presents the results of the research on the conditions, aims and outcomes of the establishment of the Faculty of Law in Subotica immediately after the First World War, at the time when the southeastern part of former Hungary considered Serbian Vojvodina became the northeastern part of the newly established Yugoslav state. This is the first institution of higher education in this area. At the beginning of the 1920s two branches of the University of Belgrade were established away from the capital, one in the northeast, and the other in the southeast of the Kingdom of Serbs, Croats and Slovenes (SCS). The establishment of the Faculty of Law in Subotica and the Faculty of Philosophy in Skopje was explained by the need to enable young people living far from Belgrade to gain higher education in the closer surroundings. In reality, the Faculty of Law in Subotica had the task of becoming a clearly recognizable and dignified border fortress. University teachers and students were expected to be sophisticated guardians of the north-eastern border of the Yugoslav kingdom. At approximately the same time, two reputable universities in Hungary, whose headquarters after the First World War remained outside Hungary, in Romania and Czechoslovakia, moved to towns near the new southeastern borders. The paper presents examples that in a special way testify of the problems and dilemmas that teachers and students of the Faculty of Law faced during the interwar period, as well as arguments to support the claim that the national mission of the Faculty of Law in Subotica significantly limited the academic autonomy of this institution of higher education.
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Pierce, Mark J., David J. Frew, Quentin A. Parker, and Joachim Köppen. "PFP 1: A Large Planetary Nebula Caught in the First Stages of ISM Interaction." Publications of the Astronomical Society of Australia 21, no. 3 (2004): 334–43. http://dx.doi.org/10.1071/as04039.
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AbstractThis paper presents (Hα + [Nii]) imaging and spectroscopy of a previously unknown, highly evolved planetary nebula of low excitation which is in the first stages of an interaction with the interstellar medium (ISM). It was discovered serendipitously from AAO/UKST Hα Survey images as part of a project to exploit the survey data and has evaded detection by previous surveys due to its very low surface brightness. It is a remarkable hollow-sphere planetary nebula, some 19´ across, making it one of the largest examples of its type. We estimate a radius of 1.5 pc and a distance of 550 pc as derived from a new Hα surface brightness–radius relation. PFP 1 has near-perfect circular symmetry, broken only at the north-western edge which is coupled with significantly increased (Hα + [Nii]) intensity, both of which provide evidence for an interaction with the ISM. We find a near solar composition for this object with possibly enhanced He and N abundances. A blue central star candidate has been identified from the SuperCosmos Sky Survey data.
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Montillaud, Julien, Mika Juvela, Charlotte Vastel, Jinhua He, Tie Liu, Isabelle Ristorcelli, David J. Eden, et al. "Multi-scale analysis of the Monoceros OB 1 star-forming region." Astronomy & Astrophysics 631 (October 11, 2019): A3. http://dx.doi.org/10.1051/0004-6361/201834903.
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Context. We started a multi-scale analysis of star formation in G202.3+2.5, an intertwined filamentary sub-region of the Monoceros OB1 molecular complex, in order to provide observational constraints on current theories and models that attempt to explain star formation globally. In the first paper (Paper I), we examined the distributions of dense cores and protostars and found enhanced star formation activity in the junction region of the filaments. Aims. In this second paper, we aim to unveil the connections between the core and filament evolutions, and between the filament dynamics and the global evolution of the cloud. Methods. We characterise the gas dynamics and energy balance in different parts of G202.3+2.5 using infrared observations from the Herschel and WISE telescopes and molecular tracers observed with the IRAM 30-m and TRAO 14-m telescopes. The velocity field of the cloud is examined and velocity-coherent structures are identified, characterised, and put in perspective with the cloud environment. Results. Two main velocity components are revealed, well separated in radial velocities in the north and merged around the location of intense N2H+ emission in the centre of G202.3+2.5 where Paper I found the peak of star formation activity. We show that the relative position of the two components along the sightline, and the velocity gradient of the N2H+ emission imply that the components have been undergoing collision for ~105 yr, although it remains unclear whether the gas moves mainly along or across the filament axes. The dense gas where N2H+ is detected is interpreted as the compressed region between the two filaments, which corresponds to a high mass inflow rate of ~1 × 10−3 M⊙ yr−1 and possibly leads to a significant increase in its star formation efficiency. We identify a protostellar source in the junction region that possibly powers two crossed intermittent outflows. We show that the H II region around the nearby cluster NCG 2264 is still expanding and its role in the collision is examined. However, we cannot rule out the idea that the collision arises mostly from the global collapse of the cloud. Conclusions. The (sub-)filament-scale observables examined in this paper reveal a collision between G202.3+2.5 sub-structures and its probable role in feeding the cores in the junction region. To shed more light on this link between core and filament evolutions, one must characterise the cloud morphology, its fragmentation, and magnetic field, all at high resolution. We consider the role of the environment in this paper, but a larger-scale study of this region is now necessary to investigate the scenario of a global cloud collapse.
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Sampangi, R. K., D. A. Glawe, T. Barlow, and S. K. Mohan. "First Report of Powdery Mildew Caused by Leveillula taurica on Giant Blazing Star (Mentzelia laevicaulis)." Plant Disease 94, no. 1 (January 2010): 132. http://dx.doi.org/10.1094/pdis-94-1-0132a.
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Mentzelia laevicaulis (Dougl. ex Hook.) Torr. & Gray (Loasaceae; common names are giant blazing star and smoothstem blazing star) is widely distributed throughout western North America in sites ranging from lowland deserts to mountainous areas in Canada and the United States. During a plant disease survey in June 2007 in the Owyhee Mountains, Canyon County, Idaho, leaves of M. laevicaulis displaying whitish, mycelial growth were collected from plants growing on stream banks and gravelly road embankments. Diseased leaves exhibited localized, chlorotic discolorations associated with signs of a powdery mildew. Of approximately 20 plants at the site, 50% were infected. White mycelia and conidia were more abundant on the adaxial leaf surfaces than on the abaxial surfaces. Severely diseased leaves were buckled and slightly twisted. By August and through September, sporulation was greatest on mature plants, and lowermost leaves were completely covered with flocculose, dense, white mycelia. Dimorphic conidia were lanceolate or cylindrical and measured (44-) 46 to 67 (-71) × (14-) 14.5 to 20 (-21) μm. DNA was extracted and PCR was used to amplify the internal transcribed spacer (ITS) region as described previously (2), except that primers ITS 5 and P3 (4) were used. The resulting 633-bp sequence (GenBank Accession No. GQ860947) included a 616-bp region identical to a sequence reported previously for Leveillula taurica (Lév.) Arnaud from eastern Washington (GenBank No. AY912077), as well as ITS regions from L. taurica previously reported from Iran (GenBank No. AB048350) (2) and Australia (GenBank No. AF 073351) (2). Based on the ITS sequence, the present fungus grouped within Khodaparast et al. (3) Clade 1 that included L. taurica strains they distinguished from other, superficially similar species of Leveillula. On the basis of morphological and sequence data, the fungus was determined to be L. taurica (1,3). A voucher specimen was deposited in the Mycology Herbarium (WSP) at Washington State University. To our knowledge, this is the first report of a named powdery mildew species from a member of the Loasaceae. The only previous report of a powdery mildew on a loasaceous host was an undetermined Oidium sp. on a species of Mentzelia (1). The discovery of L. taurica on a previously unknown native host species is further evidence that this introduced pathogen is becoming endemic to the Pacific Northwest. Native host species, such as M. laevicaulis, may play a role in the epidemiology of powdery mildew diseases caused by L. taurica on crop and ornamental species in the Pacific Northwest. References: (1) U. Braun. Beih. Nova Hedwigia 89:1, 1987. (2) D. A. Glawe et al. Mycol. Prog. 4:291, 2005. (3) S. A. Khodaparast et al. Mycol. Res. 105:909, 2001. (4) S. Takamatsu and Y. Kano. Mycoscience 42:135, 2001.
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Gelvis-Vega, Javier Eduardo, Sebastián Roa-Prada, Claudia Isabel Cáceres-Becerra, and Hernán Darío Mantilla-Hernandez. "Propuesta de arquitectura empresarial para el grupo de perforación de Ecopetrol usando el marco de referencia TOGAF." Revista Politécnica 17, no. 33 (May 21, 2021): 22–33. http://dx.doi.org/10.33571/10.33571/rpolitec.v17n33a2.
Full textAbstract:
La arquitectura empresarial permite armonizar los componentes tecnológicos de una organización definiendo un norte acorde con los objetivos y estrategias corporativas. En el grupo de geomecánica del ICP se quiere contar con elementos que sean de apoyo para generar desarrollos de herramientas software que permitan monitorear la perforación de pozos petroleros en tiempo real. Este trabajo presenta un marco conceptual de arquitectura empresarial enfocado en la optimización del flujo de información para apoyar la toma de decisiones estratégicas, generando una hoja de ruta de desarrollo de herramientas software que faciliten la gestión de información para el grupo de geomecánica del ICP. En el diseño de la arquitectura empresarial se trabajó en las seis primeras fases de la metodología ADM que proporciona TOGAF.
Enterprise architecture allows to harmonize a company’s technological components by defining a north star accord-ing to corporate goals and strategies. Ecopetrol-ICP’s geomechanics group needs to have elements to support software development for real time drilling monitoring. This work presents a conceptual framework for enterprise architecture focused on the optimization of information flow to support strategic decision-making by creating a soft-ware development roadmap to ease IT management for ICP’s geomechanics research group. In the Enterprise Architecture design with TOGAF the first six phases of the ADM cycle were implemented.
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Freire, Carla, and Joana Gonçalves. "The Relationship between Responsible Leadership and Organizational Citizenship Behavior in the Hospitality Industry." Sustainability 13, no. 9 (April 22, 2021): 4705. http://dx.doi.org/10.3390/su13094705.
Full textAbstract:
The purpose of this study is to explore the mediating role of the perception of social responsibility, and organizational identification, in the relationship between responsible leadership and organizational citizenship behavior in the hospitality industry. A questionnaire was answered by 214 frontline employees of four and five-star hotels, in the north of Portugal. Results indicate that there is a mediation model, which uses the effect of the perception of social responsibility and organizational identification in the relationship between responsible leadership and organizational citizenship behaviors. This study is a first attempt to propose a parallel multiple mediator model that explores the effect of hotel frontline employees’ perceptions of the importance of social responsibility, as well as the effect of employees’ identification with the organization, both of which act as mediators in the relationship between responsible leadership and OCB in the hospitality industry.
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Seyhan-Ozturk, Dilruba, and Semih Engin. "Genetic diversity of marbled goby populations in the Anatolian coasts of the north-eastern Mediterranean." Journal of the Marine Biological Association of the United Kingdom 101, no. 2 (March 2021): 419–29. http://dx.doi.org/10.1017/s0025315421000199.
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AbstractThe demographic histories, genetic relationships and population structure of sedentary fish Pomatoschistus marmoratus (Risso, 1810), which was sampled from the north-eastern basin of the Mediterranean Sea (including the Turkish coasts of the Black Sea, Aegean Sea, Levantine Sea and Sea of Marmara), were investigated by mitochondrial cytochrome c oxidase subunit I (652 bp) and cytochrome b (526 bp) regions. It was found that the population groups had high haplotype diversity while the nucleotide diversity was quite low for both gene regions. Phylogeographic analyses of the haplotypes indicated that the Levantine population (LEV) were genetically different from other populations. Also, the gene flow between LEV and the other populations was very limited. The results of the analyses of neutrality and mismatch distributions that were applied to the population groups were evaluated as a whole. It was determined that the haplogroup that represents the Black Sea and Sea of Marmara populations (BLAMAR) was stable, but the Levantine population (LEV) was under the sudden demographic expansion model following the population bottleneck. The genetic variance indices indicated sudden demographic expansion following population contraction. This was supported by star-shaped haplotype networks. The reason for this limited gene flow and differentiation between the Levantine population (LEV) and the others was linked with wind-driven offshore transport of the larvae and surface currents in these sub-basins. The timing of the differentiation, demographic histories of populations associated with geological and palaeo-climatic events and current ecological conditions were discussed.
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Nyalugwe, Eviness P., Calum R. Wilson, Brenda A. Coutts, and Roger A. C. Jones. "Biological Properties of Potato virus X in Potato: Effects of Mixed Infection with Potato virus S and Resistance Phenotypes in Cultivars from Three Continents." Plant Disease 96, no. 1 (January 2012): 43–54. http://dx.doi.org/10.1094/pdis-04-11-0305.
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Interactions between Potato virus X (PVX) and Potato virus S (PVS) were studied in potato plants, and isolates of PVX were inoculated to potato cultivars from four continents to identify occurrence of PVX resistance genes. Mixed infection with PVX and PVS increased the titer of PVS and enhanced expression of foliar symptoms in primarily and secondarily infected plants of ‘Royal Blue’. PVX isolates belonging to strain groups 1 and 3 (WA1+3) or 3 (XK3 and TAS3) were sap and graft inoculated (1 to 3 isolates each) to 38 cultivars and one breeding line. Presence of extreme PVX resistance gene Rx was identified in four Australian (‘Auski’, ‘Billabong’, ‘Flame’, and ‘Ruby Lou’) and two European (‘Mondial’ and ‘Rodeo’) cultivars, and in a clone of North American ‘Atlantic’. PVX hypersensitivity gene Nx was identified for the first time in two Australian (‘Bliss’ and ‘MacRusset’), four European (‘Almera’, ‘Harmony’, ‘Maxine’, and ‘Nadine’), and one North American (‘Ranger Russet’) cultivars, and in Australian breeding line 98-10713. PVX hypersensitivity gene Nb was identified for the first time in one Australian (‘White Star’), five European (‘Innovator’, ‘Kestrel’, ‘Kipfler’, ‘Laurine’, and ‘Royal Blue’), and one North American (‘Shepody’) cultivars. Probable ancestral sources of the resistance genes found in different cultivars were identified. Thus, although PVX resistance genes often occur in parents used in crosses, knowledge of their occurrence in parents and cultivars is often lacking. On sap inoculation, systemic hypersensitive phenotypes that caused shoot death often developed in cultivars with Nx but not necessarily in all shoots. This phenotype caused severe necrotic symptoms in infected tubers. In some instances, passage through cultivars with Nb separated strain group 3 from mixed isolate WA1+3.
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Roniewicz, Ewa, and George D. Stanley. "Middle Triassic cnidarians from the New Pass Range, Central Nevada." Journal of Paleontology 72, no. 2 (March 1998): 246–56. http://dx.doi.org/10.1017/s0022336000036258.
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We describe three scleractinian corals and one species of hydrozoan from the New Pass Range, central Nevada, which together constitute the oldest Triassic cnidarian assemblage from North America. They occur in carbonate rocks tentatively correlated with the Augusta Mountain Formation, Star Peak Group. At generic and higher levels, these cnidarians seem representative of early Mesozoic Tethyan faunas and carbonate lithofacies, but they indicate some endemism. Although the original aragonitic skeletons and microstructure are destroyed by recrystallization, the corals still yield important details allowing their correct taxonomic assignment. They contain the minitrabecular cerioid coral,Ceriostella variabilisnew genus and species, the thick-trabecular, thamnasteroid coralMesomorpha newpassensisnew species, and an undeterminable cuifastreid coral tentatively assigned toCuifastraea.The discovery ofMesomorphamarks the first occurrence of this genus outside the Jurassic and Cretaceous seas. Also discovered is a remarkably corallike hydrozoan,Cassianastraea reussi(Laube), already known from the Carnian stage of the western Tethys. This is the first occurrence of this species outside the western Tethys.
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Blair, David, Li Ju, Chunnong Zhao, Linqing Wen, Qi Chu, Yiqiu Ma, Michael Page, Carl Blair, Qi Fang, and Haixing Miao. "The development of ground based gravitational wave astronomy and opportunities for Australia–China collaboration." International Journal of Modern Physics A 30, no. 28n29 (October 20, 2015): 1545019. http://dx.doi.org/10.1142/s0217751x15450190.
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This paper begins by reviewing the development of gravitational wave astronomy from the first predictions of gravitational waves to development of technologies across the entire gravitational wave spectrum, and then focuses on the current status of ground based gravitational wave detectors. With substantial improvements already demonstrated in early commissioning it is emphasised that Advanced detectors are on track for first detection of gravitational waves. The importance of a worldwide array of detectors is emphasised, and recent results are shown that demonstrate the continued advantage of a southern hemisphere detector. Finally it is shown that a north–south pair of 8 km arm length detectors would give rise to a dramatic improvement in event rate, enabling a pair of detectors to encompass a 64-times larger volume of the universe, to conduct a census on all stellar mass black hole mergers to [Formula: see text] and to observe neutron star mergers to a distance of [Formula: see text][Formula: see text]800 Mpc.
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O'Dell, C. R., and A. Burkert. "The nature of the cometary knots in the Helix Nebula as determined by HST images." Symposium - International Astronomical Union 180 (1997): 332–40. http://dx.doi.org/10.1017/s0074180900131171.
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In a brief paper at the first meeting of this series, Vorontzov-Velyaminov (1968) presented the first examination of the fine scale structure found in the Helix Nebula. At that time he used the term “filaments” to describe them, although the results of improved spatial resolution during the ensuing decades (Malin 1982, Meaburn et al. 1992, Walsh & Meaburn 1993) show that the term “Cometary Knot”(CK) communicates a clearer picture of their form. The most useful groundbased images are those of Meaburn et al.(1992) made with the New Technology Telescope, which showed that each CK has a characteristic form, composed of a central dark knot, accompanied by a luminous cusp on the substellar side, and accompanied by a thin sheath of luminous material extending from the edge of the cusp to large distances. Owing to their much higher density, the Cusps are of lower ionization than the nebula as a whole, so that one sees the central dark knots, which evidently contain significant amounts of dust, in silhouette against the background nebular emission. Radio observations of the CO line show that the CK are also sources of molecular emission (Huggins et al.1992). The groundbased emission line images show that the “tails” trailing away from the Cusps lie closely on radial lines passing between the Cusp and the Central Star. Although these objects appear to be diving towards the Central Star, such an interpretation is naive, as their form must be determined by a central repulsive force arising from the star, much as true comets in our Solar System may trail their tails behind while approaching the Sun but actually follow their tails as they recede from the Sun. We also now know, from yet another excellent study by Meaburn et al. (1996) that the CK as a group are expanding away from the Central Star, although this group velocity of about 10 km s–1 is about half that value of 21 km s–1 characteristic of the nebula as a whole (Taylor 1977,Terrett 1979). The greatest breakthrough in imaging was the Hubble Space Telescope's WFPC2 (O'Dell & Handron 1996, hereafter O&H) program on a single field of view (FOV) in the north ring of the Helix in Hα, [NII], and [OIII]. One year later the same field was reimaged in [OI] and with the f547m filter, the newer observations allowing calibration of the emission line images with correction for the underlying continuum. A second, contiguous field, was also imaged, in all five filters. The results of both sets of observations are used in this paper and a combined color image is shown in the rear section of this volume. The method of calibration was the same as that used in studies of the Orion Nebula (Hu 1993). Details of the calibration and digital copies of the images can be obtained from the first author. The new observations show heretofore unseen structure which is discussed in the following sections. They indicate that there are about 3500 detectable CK in the entire Helix Nebula, with the actual number probably being much larger as strong observational selection effects operate against detection of objects far from the Central Star. The images also show that the previously known orientation along radial lines is followed, but a detailed examination shows that the tails show small local variations, as if additional, non-radial, forces are acting on them (Fig.4). O&H demonstrated that the chord diameters, measured across the cusps, decrease from about 1.8″ at 120″ distance from the Central Star to about 0.6″ at 180″. There are so many known CK that one cannot use a sequential system of designation. In this paper we will use a coordinate based system, dividing the nebula into boxes of 1″ in Declination and 0.1s of Right Ascension and dropping the values common to all of the CK. Therefore, a CK located at 22:29:42.331 −20:47:32.1 would have the designation Helix 423-732. This system will allow future studies to uniquely identify all CK with only six digits within the range of declination −20:45:00 and −20:55:00, with any objects found north or south of this range having either 4 or 5 inserted as an additional digit immediately after the hyphen. Epoch 2000 is used for the positions and the position is judged to be at the center of the dark knot.
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C. Kraan-Korteweg, Renée, Lister Staveley-Smith, Jennifer Donley, Bärbel Koribalski, and Patricia A. Henning. "The Universe Behind the Southern Milky Way." Symposium - International Astronomical Union 216 (2005): 203–10. http://dx.doi.org/10.1017/s0074180900196640.
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A first analysis of a deep blind HI survey covering the southern Zone of Avoidance plus an extension towards the north (196† ≤ ℓ ≤ 52†) obtained with the Multibeam receiver at the 64-m Parkes telescope reveals slightly over a thousand galaxies within the latitude completeness limit of |b| ≤ 5†. The characteristics and the uncovered large-scale structures of this survey are described, in particular the prominence of the Norma Supercluster, the possible cluster around PKS 1343–601 (both in the Great Attractor region), as well as the Local Void and the clustering in the Puppis region. In this blind HI survey HIZOA J0836–43 was discovered, one of the most massive spiral galaxies known to date (MHI = 7.3 × 1010 M⊙, MT = 1.1 × 1012 M⊙; H0 = 75 km/s/Mpc). Although of similar mass to Malin 1-like objects, this galaxy does not share their typical low-surface brightness properties, but seems an exceptionally massive but normal, high surface brightness, star-forming galaxy.
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Olszewski, Edward W. "Intermediate-Age Magellanic Cloud Globular Clusters." Symposium - International Astronomical Union 126 (1988): 159–72. http://dx.doi.org/10.1017/s0074180900042467.
Full textAbstract:
In this paper, I discuss some of the new facts that have been learned about Magellanic Cloud clusters, mostly thanks to new detectors and associated reduction code. I first show the extent of the LMC cluster system, in order to note that studies of age, abundance, and kinematics of the cluster system have been missing clusters to the north and south of the Hodge and Wright atlas, and to point out that star formation has gone on in places far from present day neutral hydrogen. I will concentrate on the intermediate age clusters (108-1010 y) in the discussion concerning new stellar evolution results, neglecting the 107 y clusters and 30 Doradus. I further restrict my choice of topics to 1) the luminosity of clump giants, 2) the youngest possible RR Lyrae stars, and 3) the patterns and history of cluster formation. The discussion of abundances of Cloud clusters leads readers to the excellent poster papers presented at this meeting.