The high latitude cloud Lynds 1642 is not breaking up

Symposium - International Astronomical Union ◽

10.1017/s007418090024000x ◽

1991 ◽

Vol 147 ◽

pp. 454-455

Author(s):

T. Liljeström

Keyword(s):

Radial Velocity ◽

High Latitude ◽

Core Component ◽

Halo Structure ◽

The Core ◽

Velocity Gradients ◽

Halo Gas ◽

Co Emission ◽

Cloud Core

CO, HCO+ and NH3 observations have been carried out towards the high latitude cloud L1642 using the 1.2-m GISS, the 11-m NRAO, the 14-m Metsähovi and the 100-m Effelsberg radio telescopes. The velocity field of the CO gas indicates a core-halo structure. The core component has a constant radial velocity, whereas the halo gas is slightly (> 1 km/s) redshifted, as compared to the radial velocity of the core, and shows velocity gradients towards the cloud edges in a similar way as the HI gas associated with L1642. Within the border of the 13CO emission the mass of the cloud is estimated to be some 76M⊙. In contradiction to Magnani et al.(1985), who claimed that L1642 belongs to a population of very young high latitude clouds which are breaking up, this study supports the view that L1642 is in virial equilibrium and significantly older than 106 yr. The virial equilibrium of L1642 enables a distance determination of ˜ 190 pc to the cloud core.

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Asymmetric emission of the [OIII]λ5007 profile in narrow-line Seyfert 1 galaxies

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731557 ◽

2018 ◽

Vol 615 ◽

pp. A13 ◽

Cited By ~ 7

Author(s):

E. O. Schmidt ◽

G. A. Oio ◽

D. Ferreiro ◽

L. Vega ◽

W. Weidmann

Keyword(s):

Black Hole ◽

Radial Velocity ◽

Narrow Line ◽

Black Hole Mass ◽

Core Component ◽

Velocity Difference ◽

Narrow Component ◽

The Core ◽

Central Engine ◽

Blue Wing

Context. Many active galactic nuclei (AGN) and particularly narrow-line Seyfert 1 (NLS1) galaxies, usually exhibit blueshifts and blue wings in several emission lines, which are mainly associated with outflows and strong winds. Although there is no clear evidence of the physical origin of the [OIII] blue wings, it has been suggested that they could be emitted from the inner parts of the narrow-line region (NLR). Aims. In order to study the radial velocity difference between the narrow component of Hβ and the core component of [OIII]λ5007 and the asymmetric emission of this forbidden line, we investigate a sample of NLS1 galaxies. One of the aims of this paper is to analyze the blue wings of the [OIII] 5007 profiles and their relation with the central engine. Methods. We have obtained and studied medium-resolution spectra (190 km s−1 FWHM at Hβ) of a sample of 28 NLS1 galaxies in the optical range 4300–5200 Å. We performed Gaussian decomposition to the Hβ and [OIII]λλ 4959,5007 emission profiles in order to study the distinct components of these lines. Results. A new blue outlier galaxy is found, in which the center of the core component of [OIII] is blueshifted by 405 km s−1 relative to the center of the narrow component of Hβ line. We confirmed a previously known correlation between the blueshift and the full width half maximum (FWHM) of the core component of [OIII]λ5007 line. We also corroborated the correlation between the latter and the velocity of the centroid of the blue wing. On the other hand, by studying the radial velocity difference between the blue end of the asymmetric emission and the centroid of the core component of [OIII], we found a correlation between it and the central black hole mass and, therefore, with the luminosity of the broad component of Hβ. Finally, we found a moderate correlation between the luminosity of the [OIII] blue wing and the black hole mass. Conclusions. These results suggest that the asymmetric emission of the [OIII] lines is related to the central engine, not only through the black hole but also in the intensity of the AGN, which is in agreement with previous results.

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Imaging of ribosomal RNA-protein interactions by dark-field STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153221 ◽

1989 ◽

Vol 47 ◽

pp. 250-251

Author(s):

M. Boublik ◽

V. Mandiyan ◽

S. Tumminia ◽

J.F. Hainfeld ◽

J.S. Wall

Keyword(s):

Nucleic Acid ◽

16S Rrna ◽

Dark Field ◽

Radius Of Gyration ◽

Central Domain ◽

The Core ◽

16S Rna ◽

30S Subunit ◽

Core Particles

Success in protein-free deposition of native nucleic acid molecules from solutions of selected ionic conditions prompted attempts for high resolution imaging of nucleic acid interactions with proteins, not attainable by conventional EM. Since the nucleic acid molecules can be visualized in the dark-field STEM mode without contrasting by heavy atoms, the established linearity between scattering cross-section and molecular weight can be applied to the determination of their molecular mass (M) linear density (M/L), mass distribution and radius of gyration (RG). Determination of these parameters promotes electron microscopic imaging of biological macromolecules by STEM to a quantitative analytical level. This technique is applied to study the mechanism of 16S rRNA folding during the assembly process of the 30S ribosomal subunit of E. coli. The sequential addition of protein S4 which binds to the 5'end of the 16S rRNA and S8 and S15 which bind to the central domain of the molecule leads to a corresponding increase of mass and increased coiling of the 16S rRNA in the core particles. This increased compactness is evident from the decrease in RG values from 114Å to 91Å (in “ribosomal” buffer consisting of 10 mM Hepes pH 7.6, 60 mM KCl, 2 m Mg(OAc)2, 1 mM DTT). The binding of S20, S17 and S7 which interact with the 5'domain, the central domain and the 3'domain, respectively, continues the trend of mass increase. However, the RG values of the core particles exhibit a reverse trend, an increase to 108Å. In addition, the binding of S7 leads to the formation of a globular mass cluster with a diameter of about 115Å and a mass of ∽300 kDa. The rest of the mass, about 330 kDa, remains loosely coiled giving the particle a “medusa-like” appearance. These results provide direct evidence that 16S RNA undergoes significant structural reorganization during the 30S subunit assembly and show that its interactions with the six primary binding proteins are not sufficient for 16S rRNA coiling into particles resembling the native 30S subunit, contrary to what has been reported in the literature.

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Nauwkeurige methode voor de aanwasbepaling van het grondvlak met behulp van de Pressler-boor

Silva Gandavensis ◽

10.21825/sg.v12i0.1009 ◽

1968 ◽

Vol 12 ◽

Author(s):

R. Goossens

Keyword(s):

Basal Area ◽

Precise Determination ◽

Maximum Diameter ◽

Precise Method ◽

Maximum Radius ◽

The Core ◽

Two Parameters

A precise method for the determination of the increment of the basal area using the PressIer bore. Refering to previous research showing that the basal area of the corsica pine could be characterized by an ellips, we present in this paper a precise method for the determination of the increment of the basal area. In this method we determine the direction of the maximum diameter, we measure this diameter and we take a core in one of the points of tangency of the caliper with the measured tree. The determination of the diameter perpendicular to the maximum diameter finishes the work wich is to be done in the forest. From the classical measurements effectuated on the core and from the measured diameters we can then determine the form (V) and the excentricity (e). Substituting these two parameters in the formula 2 or 2', we can also calculate the error of a radius measured on the core with respect to the representative radius, This error with them allow us to correct the measured value of the minimum or the maximum radius and we will be able to do a precise determination of the increment.

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Avolition as the core negative symptom in schizophrenia: relevance to pharmacological treatment development

npj Schizophrenia ◽

10.1038/s41537-021-00145-4 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Gregory P. Strauss ◽

Lisa A. Bartolomeo ◽

Philip D. Harvey

Keyword(s):

Negative Symptom ◽

Negative Symptoms ◽

Clinical Trial Design ◽

Core Component ◽

Treatment Target ◽

Global Improvement ◽

Treatment Development ◽

The Core ◽

Current Review ◽

Symptom Domains

AbstractNegative symptoms have long been considered a core component of schizophrenia. Modern conceptualizations of the structure of negative symptoms posit that there are at least two broad dimensions (motivation and pleasure and diminished expression) or perhaps five separable domains (avolition, anhedonia, asociality, blunted affect, alogia). The current review synthesizes a body of emerging research indicating that avolition may have a special place among these dimensions, as it is generally associated with poorer outcomes and may have distinct neurobiological mechanisms. Network analytic findings also indicate that avolition is highly central and interconnected with the other negative symptom domains in schizophrenia, and successfully remediating avolition results in global improvement in the entire constellation of negative symptoms. Avolition may therefore reflect the most critical treatment target within the negative symptom construct. Implications for targeted treatment development and clinical trial design are discussed.

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Formation of an Iron(III) Oxo Cubane Core Fe4(μ4-O)4 from FeCl3 and the Unsymmetrical Tripodal Ligand N[(CH2CH2NH2)(CH2CH2OH)(CH2CH2CH2OH)]

Zeitschrift für Naturforschung B ◽

10.1515/znb-2004-0815 ◽

2004 ◽

Vol 59 (8) ◽

pp. 855-858 ◽

Cited By ~ 4

Author(s):

Ekkehardt Hahn ◽

Christoph Jocher ◽

Thomas Lügger

Keyword(s):

Coordination Chemistry ◽

Structure Determination ◽

Disodium Salt ◽

Ferrous Chloride ◽

Tripodal Ligand ◽

The Core ◽

Yellow Precipitate

AbstractThe coordination chemistry of the unsymmetric, aliphatic, tetradentate tripodal ligand N[(CH2CH2NH2)(CH2CH2OH)(CH2CH2CH2OH)] H4-1 with iron chlorides was investigated. The disodium salt of the deprotonated ligand Na2(H2-1) reacts with FeCl3 to yield a yellow precipitate which upon recrystallization from DMSO/CH2Cl2 gives red crystals of the octanuclear iron(III) complex [{FeIIICl(H2-1)}4FeIII4(μ4-O)4Cl4] 2 ・ 4CH2Cl2 containing a central Fe4(μ4-O)4 cubane core. Crystals of 2 ・4DMF were obtained by slow oxidation of the green iron(II) complex obtained from ferrous chloride and Na2(H2-1) after recrystallization from DMF. The structure determination of 2 ・4CH2Cl2 also revealed the presence of the iron(III) oxo cubane core. The core is surrounded by four iron atoms each coordinated by η4-(H2-1)2- and Cl- ligands.

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Lin28, a major translation reprogramming factor, gains access to YB-1-packaged mRNA through its cold-shock domain

Communications Biology ◽

10.1038/s42003-021-01862-3 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Anastasiia Samsonova ◽

Krystel El Hage ◽

Bénédicte Desforges ◽

Vandana Joshi ◽

Marie-Jeanne Clément ◽

...

Keyword(s):

Cancer Progression ◽

Cold Shock ◽

Rna Binding ◽

Rna Binding Proteins ◽

Rna Binding Protein ◽

Large Set ◽

Core Component ◽

The Core ◽

Cold Shock Domain ◽

Global Translation

AbstractThe RNA-binding protein Lin28 (Lin28a) is an important pluripotency factor that reprograms translation and promotes cancer progression. Although Lin28 blocks let-7 microRNA maturation, Lin28 also binds to a large set of cytoplasmic mRNAs directly. However, how Lin28 regulates the processing of many mRNAs to reprogram global translation remains unknown. We show here, using a structural and cellular approach, a mixing of Lin28 with YB-1 (YBX1) in the presence of mRNA owing to their cold-shock domain, a conserved β-barrel structure that binds to ssRNA cooperatively. In contrast, the other RNA binding-proteins without cold-shock domains tested, HuR, G3BP-1, FUS and LARP-6, did not mix with YB-1. Given that YB-1 is the core component of dormant mRNPs, a model in which Lin28 gains access to mRNPs through its co-association with YB-1 to mRNA may provide a means for Lin28 to reprogram translation. We anticipate that the translational plasticity provided by mRNPs may contribute to Lin28 functions in development and adaptation of cancer cells to an adverse environment.

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Enhancing Postgraduate Learning and Teaching: Postgraduate Summer School in Dairy Science

Veterinary Medicine International ◽

10.1155/2014/409549 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Pietro Celi ◽

Gianfranco Gabai ◽

Massimo Morgante ◽

Luigi Gallo

Keyword(s):

Summer School ◽

Research Collaboration ◽

Learning Experience ◽

Scientific Investigation ◽

Core Component ◽

Learning And Teaching ◽

Transferable Skills ◽

The Core ◽

Dairy Science ◽

The University

Dairy science is a multidisciplinary area of scientific investigation and Ph.D. students aiming to do research in the field of animal and/or veterinary sciences must be aware of this. Ph.D. students often have vast spectra of research interests, and it is quite challenging to satisfy the expectation of all of them. The aim of this study was to establish an international Ph.D. training program based on research collaboration between the University of Sydney and the University of Padova. The core component of this program was a two-week Postgraduate Summer School in Dairy Science, which was held at the University of Padova, for Ph.D. students of both universities. Therefore, we designed a program that encompassed seminars, workshops, laboratory practical sessions, and farm visits. Participants were surveyed using a written questionnaire. Overall, participants have uniformly praised the Summer School calling it a rewarding and valuable learning experience. The Ph.D. Summer School in Dairy Science provided its participants a positive learning experience, provided them the opportunity to establish an international network, and facilitated the development of transferable skills.

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