scholarly journals Lack of high-mass pre-stellar cores in the starless MDCs of NGC 6334

2019 ◽  
Vol 622 ◽  
pp. A99 ◽  
Author(s):  
F. Louvet ◽  
S. Neupane ◽  
G. Garay ◽  
D. Russeil ◽  
A. Zavagno ◽  
...  
Keyword(s):  
Initial Conditions ◽  
Compact Objects ◽  
The Other ◽  
High Mass ◽  
Mass Star ◽  
Dense Cores ◽  
Other Hand ◽  
Static Models ◽  
Ngc 6334 ◽  
The One

Context. The formation of high-mass stars remains unknown in many aspects. There are two competing families of models to explain the formation of high-mass stars. On the one hand, quasi-static models predict the existence of high-mass pre-stellar cores sustained by a high degree of turbulence. On the other hand, competitive accretion models predict that high-mass proto-stellar cores evolve from low or intermediate mass proto-stellar cores in dynamic environments. Aims. The aim of the present work is to bring observational constraints at the scale of high-mass cores (~0.03 pc). Methods. We targeted with ALMA and MOPRA a sample of nine starless massive dense cores (MDCs) discovered in a recent Herschel/HOBYS study. Their mass and size (~110 M⊙ and r = 0.1 pc, respectively) are similar to the initial conditions used in the quasi-static family of models explaining for the formation of high-mass stars. We present ALMA 1.4 mm continuum observations that resolve the Jeans length (λJeans ~ 0.03 pc) and that are sensitive to the Jeans mass (MJeans ~ 0.65 M⊙) in the nine starless MDCs, together with ALMA-12CO(2–1) emission line observations. We also present HCO+(1–0), H13CO+(1–0) and N2H+(1–0) molecular lines from the MOPRA telescope for eight of the nine MDCs. Results. The nine starless MDCs have the mass reservoir to form high-mass stars according to the criteria by Baldeschi et al. (2017). Three of the starless MDCs are subvirialized with αvir ~ 0.35, and four MDCs show sign of collapse from their molecular emission lines. ALMA observations show very little fragmentation within the MDCs. Only two of the starless MDCs host compact continuum sources, whose fluxes correspond to <3 M⊙ fragments. Therefore, the mass reservoir of the MDCs has not yet been accreted onto compact objects, and most of the emission is filtered out by the interferometer. Conclusions. These observations do not support the quasi-static models for high-mass star formation since no high-mass pre-stellar core is found in NGC 6334. The competitive accretion models, on the other hand, predict a level of fragmentation much higher than what we observe.

scholarly journals Dense cores in the Seahorse infrared dark cloud: physical properties from modified blackbody fits to the far-infrared–submillimetre spectral energy distributions

2020 ◽  
Vol 644 ◽  
pp. A82
Author(s):  
O. Miettinen
Keyword(s):  
Star Formation ◽  
Physical Properties ◽  
Initial Conditions ◽  
High Mass ◽  
Spectral Energy ◽  
Mass Star ◽  
Wide Field ◽  
Spectral Energy Distributions ◽  
Energy Distributions ◽  
Dense Cores

Context. Infrared dark clouds (IRDCs) can be the birth sites of high-mass stars, and hence determining the physical properties of dense cores in IRDCs is useful to constrain the initial conditions and theoretical models of high-mass star formation. Aims. We aim to determine the physical properties of dense cores in the filamentary Seahorse IRDC G304.74+01.32. Methods. We used data from the Wide-field Infrared Survey Explorer (WISE), Infrared Astronomical Satellite (IRAS), and Herschel in conjuction with our previous 350 and 870 μm observations with the Submillimetre APEX Bolometer Camera (SABOCA) and Large APEX BOlometer CAmera, and constructed the far-IR to submillimetre spectral energy distributions (SEDs) of the cores. The SEDs were fitted using single or two-temperature modified blackbody emission curves to derive the dust temperatures, masses, and luminosities of the cores. Results. For the 12 analysed cores, which include two IR dark cores (no WISE counterpart), nine IR bright cores, and one H II region, the mean dust temperature of the cold (warm) component, the mass, luminosity, H2 number density, and surface density were derived to be 13.3 ± 1.4 K (47.0 ± 5.0 K), 113 ± 29 M⊙, 192 ± 94 L⊙, (4.3 ± 1.2) × 105 cm−3, and 0.77 ± 0.19 g cm−3, respectively. The H II region IRAS 13039-6108a was found to be the most luminous source in our sample ((1.1 ± 0.4) × 103 L⊙). All the cores were found to be gravitationally bound (i.e. the virial parameter αvir < 2). Two out of the nine analysed IR bright cores (22%) were found to follow an accretion luminosity track under the assumptions that the mass accretion rate is 10−5 M⊙ yr−1, the stellar mass is 10% of the parent core mass, and the radius of the central star is 5 R⊙. Most of the remaing ten cores were found to lie within 1 dex below this accretion luminosity track. Seven out of 12 of the analysed cores (58%) were found to lie above the mass-radius thresholds of high-mass star formation proposed in the literature. The surface densities of Σ > 0.4 g cm−3 derived for these seven cores also exceed the corresponding threshold for high-mass star formation. Five of the analysed cores (42%) show evidence of fragmentation into two components in the SABOCA 350 μm image. Conclusions. In addition to the H II region source IRAS 13039-6108a, some of the other cores in Seahorse also appear to be capable of giving birth to high-mass stars. The 22 μm dark core SMM 9 is likely to be the youngest source in our sample that has the potential to form a high-mass star (96 ± 23 M⊙ within a radius of ~0.1 pc). The dense core population in the Seahorse IRDC has comparable average properties to the cores in the well-studied Snake IRDC G11.11-0.12 (e.g. Tdust and L agree within a factor of ~1.8); furthermore, the Seahorse, which lies ~60 pc above the Galactic plane, appears to be a smaller (e.g. three times shorter in projection, ~100 times less massive) version of the Snake. The Seahorse core fragmentation mechanisms appear to be heterogenous, including cases of both thermal and non-thermal Jeans instability. High-resolution follow-up studies are required to address the fragmented cores’ genuine potential of forming high-mass stars.

scholarly journals Probing fragmentation and velocity sub-structure in the massive NGC 6334 filament with ALMA

2019 ◽  
Vol 632 ◽  
pp. A83 ◽  
Author(s):  
Y. Shimajiri ◽  
Ph. André ◽  
E. Ntormousi ◽  
A. Men’shchikov ◽  
D. Arzoumanian ◽  
...  
Keyword(s):  
Star Formation ◽  
Velocity Structure ◽  
High Mass ◽  
Mass Star ◽  
Star Forming ◽  
Dense Cores ◽  
Order Of Magnitude ◽  
Low Mass ◽  
Ngc 6334 ◽  
Main Filament

Context. Herschel imaging surveys of galactic interstellar clouds support a paradigm for low-mass star formation in which dense molecular filaments play a crucial role. The detailed fragmentation properties of star-forming filaments remain poorly understood, however, and the validity of the filament paradigm in the intermediate- to high-mass regime is still unclear. Aims. Here, following up on an earlier 350 μm dust continuum study with the ArTéMiS camera on the APEX telescope, we investigate the detailed density and velocity structure of the main filament in the high-mass star-forming region NGC 6334. Methods. We conducted ALMA Band 3 observations in the 3.1 mm continuum and of the N2H+(1–0), HC5N(36–35), HNC(1–0), HC3N(10–9), CH3CCH(6–5), and H2CS(3–2) lines at an angular resolution of ~3′′, corresponding to 0.025 pc at a distance of 1.7 kpc. Results. The NGC 6334 filament was detected in both the 3.1 mm continuum and the N2H+, HC3N, HC5N, CH3CCH, and H2CS lines with ALMA. We identified twenty-six compact (<0.03 pc) dense cores at 3.1 mm and five velocity-coherent fiber-like features in N2H+ within the main filament. The typical length (~0.5 pc) of, and velocity difference (~0.8 km s−1) between, the fiber-like features of the NGC 6334 filament are reminiscent of the properties for the fibers of the low-mass star-forming filament B211/B213 in the Taurus cloud. Only two or three of the five velocity-coherent features are well aligned with the NGC 6334 filament and may represent genuine, fiber sub-structures; the other two features may trace accretion flows onto the main filament. The mass distribution of the ALMA 3.1 mm continuum cores has a peak at ~10 M⊙, which is an order of magnitude higher than the peak of the prestellar core mass function in nearby, low-mass star-forming clouds. The cores can be divided into seven groups, closely associated with dense clumps seen in the ArTéMiS 350 μm data. The projected separation between ALMA dense cores (0.03–0.1 pc) and the projected spacing between ArTéMiS clumps (0.2–0.3 pc) are roughly consistent with the effective Jeans length (0.08 ± 0.03 pc) in the filament and a physical scale of about four times the filament width, respectively, if the inclination angle of the filament to line of sight is ~30°. These two distinct separation scales are suggestive of a bimodal fragmentation process in the filament. Conclusions. Despite being one order of magnitude denser and more massive than the Taurus B211/B213 filament, the NGC 6334 filament has a density and velocity structure that is qualitatively very similar. The main difference is that the dense cores embedded in the NGC 6334 filament appear to be an order of magnitude denser and more massive than the cores in the Taurus filament. This suggests that dense molecular filaments may evolve and fragment in a similar manner in low- and high-mass star-forming regions, and that the filament paradigm may hold in the intermediate-mass (if not high-mass) star formation regime.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Primary Tumour ◽  
The Other ◽  
Haematopoietic Stem Cell ◽  
Other Hand ◽  
Primary Reduction ◽  
The One ◽  
Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

The Salvage of Ideas: Schumpeter and the Core Problems Still Confronting Economics

2003 ◽  
pp. 15-26
Author(s):  
P. Wynarczyk
Keyword(s):  
The Other ◽  
The Core ◽  
Other Hand ◽  
The One

Two aspects of Schumpeter' legacy are analyzed in the article. On the one hand, he can be viewed as the custodian of the neoclassical harvest supplementing to its stock of inherited knowledge. On the other hand, the innovative character of his works is emphasized that allows to consider him a proponent of hetherodoxy. It is stressed that Schumpeter's revolutionary challenge can lead to radical changes in modern economics.

Pembaharuan Pesantren: Arah dan Implikasi

2018 ◽  
Vol 4 (1) ◽  
pp. 67-84
Author(s):  
Wahyudin Noor
Keyword(s):  
Rapid Development ◽  
The Other ◽  
Learning Methods ◽  
Technology Learning ◽  
Other Hand ◽  
The One ◽  
Traditional Term

Abstract Pesantren are often associated with backwardness and traditionalism in everything: facilities, technology, learning methods, and even the curriculum. For now, it seems like the traditional term for pesantren is no longer relevant enough. The pace of movement in the era of renewal marked by the rapid development of technology has demanded pesantren to make adjustments. However, on the one hand, when viewed from the direction of change, the reform efforts pursued by pesantren are not to erase the old tradition, but merely to add something new so that the old tradition and conditions can be maintained while accepting the presence of a new one. On the other hand, the reform efforts undertaken by pesantren have implications for the fact that the typical values of the pesantren are fading away. Abstrak  Pesantren seringkali diasosiasikan dengan keterbelakangan dan tradisional dalam segala hal: fasilitas, teknologi, metode pembelajaran, dan bahkan kurikulumnya. Untuk saat ini, sepertinya istilah tradisional untuk pesantren, sudah tidak lagi cukup relevan. Laju gerak pembaharuan zaman yang ditandai dengan pesatnya perkembangan teknologi telah menuntut pesantren untuk melakukan penyesuaian diri. Kendatipun demikian, di satu sisi, jika dilihat dari arah perubahan, upaya pembaharuan yang ditempuh pesantren tidaklah untuk menghapus tradisi yang lama, tetapi sekadar menambah dengan sesuatu yang baru sehingga tradisi maupun kondisi yang lama bisa dipertahankan sambil menerima kehadiran yang baru. Di sisi yang lain, upaya pembaharuan yang dilakukan pesantren ternyata berimplikasi pada kenyataan akan semakin pudarnya nilai-nilai khas yang dimiliki oleh pesantren.

PROBLEMATIKA HUKUM IMPLEMENTASI SIFAT FINAL DAN BINDING PUTUSAN YANG DIBUAT OLEH BASYARNAS DALAM PENYELESAIAN SENGKETA BISNIS SYARIAH

2018 ◽  
Vol 1 (1) ◽  
pp. 37-52
Author(s):  
Karimatul Khasanah
Keyword(s):  
The Other ◽  
Other Hand ◽  
The One

BASYARNAS’s verdict in resolving dispute can be negotiated or cancelled by submitting nullification to the Religious Court if the parties or one of them felt dissatisfied with the BASYARNAS verdicts. This case is important to be reviewed academically because of its paradox and ambiguity. On the one hand the decision is final and binding, but on the other hand it could be cancelled through the Religious Court. If the BASYARNAS verdicts really want to be final and binding, the nullification of the verdicts should be abolished. It can be replaced by an amendment of the verdict submitted to BASYARNAS and handed back to the arbitrator (arbitrator panel) who handles the dispute. Apart being fast and confidential, the arbitrator (judge) is more aware of the case, the reasons, evidences and witnesses of the dispute.

Correspondances étymologiques, lexicales et sémantiques dans le processus de féminisation de noms de profession, métiers et activités dans les sociétés française et roumaine

2020 ◽  
Vol 65 (4) ◽  
pp. 401-422
Author(s):  
Estelle Variot
Keyword(s):  
The Other ◽  
Roman World ◽  
Other Hand ◽  
The One ◽  
Over Time

"Etymological, Lexical and Semantic Correspondences in the Process of Feminization of Professional Names, Trades and Activities in French and Romanian Societies. The feminization of thought represented by language and of its varieties in the Roman World has allowed to highlight some convergences that come from a common linguistic heritage, often from Greek and Latin and some hesitation about adapting society to its realities. The feminization of some words which comes from an ancient process illustrates on the one hand the potential of the language and on the other hand some constraints sometimes linked to the society itself, which creates transitional periods, between matching grammatical correction and the evolution of linguistic uses over time. The possibilities of lexical enrichment (internal creation or loan) show the means available in French and Romanian and some convergences in the area of derivation, of lexical units and their etymologies. The grammatical perspective and word constructing methods make it possible to give keys for the feminization of names of trades or professions. Likewise, recording entries in the lexicon, their evolution, their assimilation or sometimes their forgetfulness, for the benefit of new constructions highlight the existence of objective and subjective criteria which teach us a lot about society as a whole. Keywords: feminization of professions, internal and external enrichment, suffixal match, use of words, grammar, lexicon, French and Romanian."

Challenging Gender Hierarchies in Narratives of the Nation: Representations of Women in Zintgraff and the Battle of Mankon and Hard Choice

Imbizo ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Naomi Epongse Nkealah ◽  
Olutoba Gboyega Oluwasuji
Keyword(s):  
The Other ◽  
Literary Texts ◽  
Gender Differentiation ◽  
Hard Choice ◽  
Other Hand ◽  
Gender Hierarchies ◽  
The Face ◽  
The One ◽  
Representations Of Women ◽  
Do So

Ideas of nationalisms as masculine projects dominate literary texts by African male writers. The texts mirror the ways in which gender differentiation sanctions nationalist discourses and in turn how nationalist discourses reinforce gender hierarchies. This article draws on theoretical insights from the work of Anne McClintock and Elleke Boehmer to analyse two plays: Zintgraff and the Battle of Mankon by Bole Butake and Gilbert Doho and Hard Choice by Sunnie Ododo. The article argues that women are represented in these two plays as having an ambiguous relationship to nationalism. On the one hand, women are seen actively changing the face of politics in their societies, but on the other hand, the means by which they do so reduces them to stereotypes of their gender.

Estruturas comparativas complexas: variação e desvio e questões de tradução

2019 ◽  
pp. 265-286
Author(s):  
Telmo Móia ◽  
Rui Marques
Keyword(s):  
Prime Minister ◽  
The Other ◽  
Other Hand ◽  
Comparative Constructions ◽  
Game Console ◽  
The One

In this paper, we analyse two subtypes of related comparative constructions in Portuguese, with a focus on grammatical anomaly and change – whether expressed in translated text, as a result of calquing (from English), or in autochthonous text, evincing an area of grammatical instability and change in progress. These are: on the one hand, comparative clauses using multiplicative numbers or fractions, like the Portuguese counterparts of the president is twice as popular as the prime minister or women are four times less likely to develop coronary problems than men, and, on the other hand, nominal phrases resorting to the same quantifying operators, but in a non-clausal environment, like the counterparts of Spain has twice the level of unemployment of Portugal or this game console has four times the memory of the previous one. The observed anomalies – or disputed constructions – involve the non-canonical: (i) use of equative operators (tão/tanto, ‘as’) in comparative clauses with multiplicative numbers or fractions (likely, as a result of calquing from English); (ii) use of a connective (que/do que, ‘than’) in nominal phrases with quantifying operators similar to those of comparative clauses (likely, as a result of autochthonous hybridization); (iii) use of complex prepositional expressions like comparativamente com (‘in comparison with’) or em relação a (‘relatively to’) either instead of the connective (do) que in comparative clauses, or before modifiers inside nominal phrases with multiplicative numbers or fractions. Overall, an intriguing area of grammatical unrest is discussed, with a particular focus on its bearing on translating texts into standard Portuguese.

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