scholarly journals Diffuse glioneuronal tumour with oligodendroglioma like features and nuclear clusters

2021 ◽  
Author(s):  
Francesco Buemi
Keyword(s):  
Nuclear Clusters

scholarly journals The accreted nuclear clusters of the Milky Way

2020 ◽  
Vol 500 (2) ◽  
pp. 2514-2524
Author(s):  
Joel Pfeffer ◽  
Carmela Lardo ◽  
Nate Bastian ◽  
Sara Saracino ◽  
Sebastian Kamann
Keyword(s):  
Globular Clusters ◽  
Milky Way ◽  
Dwarf Galaxy ◽  
Star Clusters ◽  
Host Galaxy ◽  
The Galaxy ◽  
Nuclear Clusters ◽  
The Common ◽  
Massive Clusters ◽  
Peculiar Case

ABSTRACT A number of the massive clusters in the halo, bulge, and disc of the Galaxy are not genuine globular clusters (GCs) but instead are different beasts altogether. They are the remnant nuclear star clusters (NSCs) of ancient galaxies since accreted by the Milky Way. While some clusters are readily identifiable as NSCs and can be readily traced back to their host galaxy (e.g. M54 and the Sagittarius Dwarf galaxy), others have proven more elusive. Here, we combine a number of independent constraints, focusing on their internal abundances and overall kinematics, to find NSCs accreted by the Galaxy and trace them to their accretion event. We find that the true NSCs accreted by the Galaxy are: M54 from the Sagittarius Dwarf, ω Centari from Gaia-Enceladus/Sausage, NGC 6273 from Kraken, and (potentially) NGC 6934 from the Helmi Streams. These NSCs are prime candidates for searches of intermediate-mass black holes (BHs) within star clusters, given the common occurrence of galaxies hosting both NSCs and central massive BHs. No NSC appears to be associated with Sequoia or other minor accretion events. Other claimed NSCs are shown not to be such. We also discuss the peculiar case of Terzan 5, which may represent a unique case of a cluster–cluster merger.

Nuclear Clusters in Astrophysics

2010 ◽  
Vol 834 (1-4) ◽  
pp. 647c-650c ◽  
Author(s):  
S. Kubono ◽  
Dam N. Binh ◽  
S. Hayakawa ◽  
H. Hashimoto ◽  
D. Kahl ◽  
...  
Keyword(s):  
Nuclear Clusters

scholarly journals Graph Theory of Chemical Series and Broad Categorization of Clusters

2018 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Enos Masheija Rwantale Kiremire
Keyword(s):  
Graph Theory ◽  
Transition Metal ◽  
Metal Clusters ◽  
Transition Metal Clusters ◽  
Recent Introduction ◽  
Simple Concept ◽  
Wide Range ◽  
Nuclear Clusters

The recent introduction of skeletal numbers has made it much easier to analyze and categorize a wide range of many chemical clusters. In the process, it has been found that a large number of transition metal clusters with and without ligands are capped and do possess closo nuclear clusters. On the basis of the nuclear index, the clusters have been categorized into groups. The categorization of the clusters will greatly assist in promoting deeper understanding and the synthesis of novel clusters and their applications. A simple concept of graph theory of capping clusters has been introduced.

scholarly journals Rapid dispersal of clustered postsynaptic nuclei following dissociation of skeletal muscle fibers.

1996 ◽  
Vol 199 (11) ◽  
pp. 2359-2367
Author(s):  
C Brösamle ◽  
D P Kuffler
Keyword(s):  
Skeletal Muscle ◽  
Synapse Formation ◽  
Contractile Activity ◽  
Muscle Fibers ◽  
Skeletal Muscle Fibers ◽  
Synaptic Region ◽  
Nuclear Clusters ◽  
Specialized Structure

The vertebrate neuromuscular junction is a highly specialized structure containing many unique proteins and an underlying cluster of nuclei. Part of this specialization results from the expression of the genes for these proteins in nuclei clustered in the postsynaptic region. Contractile activity, as well as molecules located in the synaptic extracellular matrix (ECM), have been implicated in the induction of gene expression in these clustered nuclei. The present experiments were aimed at examining whether the presence of the synaptic ECM and presynaptic cells play a role in maintaining the clustering of the nuclei. We describe the normal distribution of nuclei clustered in the synaptic region of intact adult frog, Rana pipiens, skeletal muscle fibers and show that innervation is not required to maintain the nuclear clusters. Even after long-term (4 week) denervation, the clusters remain unchanged. Dissociation of the muscle fibers with proteases that remove ECM, Schwann cells and other satellite cells from the synaptic sites is followed by a rapid (within approximately 1.5 h) and almost complete dispersal of the clustered nuclei. Attempts to recluster the postsynaptic nuclei by the application of ECM components to muscle fibers in vitro were not successful. We propose that a factor or factors, localized in the synaptic ECM as a result of synapse formation and acting via the transmembrane or cytoplasmic domains of their respective receptors, induces the formation of a specialized cytoskeleton in the postsynaptic region that is capable of pulling in or 'trapping' nuclei. The removal of these factors from the ECM by proteases brings about the disorganization of the cytoskeleton and the freeing of the 'trapped' nuclei.

scholarly journals Non-spherical nucleon clusters in the mantle of a neutron star: CLDM based on Skyrme-type forces

2021 ◽  
Vol 2103 (1) ◽  
pp. 012004
Author(s):  
N A Zemlyakov ◽  
A I Chugunov ◽  
N N Shchechilin
Keyword(s):  
Neutron Star ◽  
Nuclear Matter ◽  
Liquid Drop ◽  
Outer Region ◽  
Spherical Shape ◽  
Baryon Number ◽  
Compressible Liquid ◽  
Liquid Drop Model ◽  
The Core ◽  
Nuclear Clusters

Abstract Neutron stars are superdense compact astrophysical objects. The central region of the neuron star (the core) consists of locally homogeneous nuclear matter, while in the outer region (the crust) nucleons are clustered. In the outer crust these nuclear clusters represent neutron-rich atomic nuclei and all nucleons are bound within them. Whereas in the inner crust some neutrons are unbound, but nuclear clusters still keeps generally spherical shape. Here we consider the region between the crust and the core of the star, so-called mantle, where non-spherical nuclear clusters may exist. We apply compressible liquid drop model to calculate the energy density for several shape types of nuclear clusters. It allows us to identify the most energetically favorable configuration as function of baryon number density. Employing four Skyrme-type forces (SLy4 and BSk24, BSk25, BSk26), which are widely used in the neutron star physics, we faced with strong model dependence of the ground state composition. In particular, in agreement with previous works within liquid drop model, mantle is absent for SLy4 (nuclear spheres directly transit into homogeneous nuclear matter; exotic nuclear shapes do not appear).

Metal Directed One-Pot Syntheses: Mono-, Di- and Tetra-Nuclear Clusters [1]

2003 ◽  
Vol 58 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Rolf W. Saalfrank ◽  
Uwe Reimann ◽  
Frank Hampel ◽  
Cornelia Goebel ◽  
Regine Herbst-Irmer
Keyword(s):  
Nickel Acetate ◽  
One Pot ◽  
Aerobic Conditions ◽  
Nuclear Complex ◽  
Nuclear Clusters ◽  
Nuclear Cluster ◽  
Nitrogen Donors

Abstract Upon reaction of HL1 1 (picoline-tetrazolylamide) with cobalt(II) acetate under aerobic conditions or with copper(II) acetate, the mono-nuclear complex [CoIII(L1)3] 3 and the di-nuclear complex [Cu2(L1)4] 4 were generated. In 3 and 4, (L1)− exclusively coordinates across its nitrogen donors. However, when HL2 5 (picoline-tetrazolylthioamide) was reacted with copper- or nickel acetate, the di-nuclear cluster [Cu2(L2)4] 6 and the tetra-nuclear cluster [Ni4(L2)8] 7, respectively, were isolated. Contrary to 3 and 4, in 6 and 7, (L2)− also coordinates across sulfur.

A heterometallic metal–organic framework based on multi-nuclear clusters exhibiting high stability and selective gas adsorption

2019 ◽  
Vol 48 (1) ◽  
pp. 278-284 ◽  
Author(s):  
Dongmei Wang ◽  
Zihua Liu ◽  
Lili Xu ◽  
Chunxia Li ◽  
Dian Zhao ◽  
...  
Keyword(s):  
Chemical Stability ◽  
High Performance ◽  
High Stability ◽  
Gas Adsorption ◽  
Metal Organic Framework ◽  
Gas Storage ◽  
Nuclear Clusters ◽  
Metal Organic ◽  
Thermal And Chemical Stability ◽  
Organic Framework

Porous In/Tb-CBDA has been successfully synthesized in the light of the heterometallic cooperative crystallization (HCC) approach. In/Tb-CBDA with high thermal and chemical stability exhibited high performance for gas storage and separation.

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