748 research outputs found
Poly[μ2-aqua-aqua(μ3-1H-benzimidazole-5,6-dicarboxylato-κ3 N 3:O 5:O 5′)manganese(II)]
In the title complex, [Mn(C9H4N2O4)(H2O)2]n, the MnII atom is in a distorted octahedral coordination completed by one N atom from one 1H-benzimidazole-5,6-dicarboxylate ligand, two O atoms from two different 1H-benzimidazole-5,6-dicarboxylate ligands, and three O atoms from three water molecules. Two bridging water molecules and two bridging carboxylate groups from a 1H-benzimidazole-5,6-dicarboxylate ligand connect two MnII ions into a dimeric structure. In the crystal, extensive intermolecular O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonding forms a three-dimensional network
Formation of a tiny flux rope in the center of an active region driven by magnetic flux emergence, convergence, and cancellation
Flux ropes are generally believed to be core structures of solar eruptions
that are significant for the space weather, but their formation mechanism
remains intensely debated. We report on the formation of a tiny flux rope
beneath clusters of active region loops on 2018 August 24. Combining the
high-quality multiwavelength observations from multiple instruments, we studied
the event in detail in the photosphere, chromosphere, and corona. In the source
region, the continual emergence of two positive polarities (P1 and P2) that
appeared as two pores (A and B)is unambiguous. Interestingly, P2 and Pore B
slowly approached P1 and Pore A, implying a magnetic flux convergence. During
the emergence and convergence, P1 and P2 successively interacted with a minor
negative polarity (N3) that emerged, which led to a continuous magnetic flux
cancellation. As a result, the overlying loops became much sheared and finally
evolved into a tiny twisted flux rope that was evidenced by a transient inverse
S-shaped sigmoid, the twisted filament threads with blueshift and redshift
signatures, and a hot channel. All the results show that the formation of the
tiny flux rope in the center of the active region was closely associated with
the continuous magnetic flux emergence, convergence, and cancellation in the
photosphere. Hence, we suggest that the magnetic flux emergence, convergence,
and cancellation are crucial for the formation of the tiny flux rope
Self-gated late gadolinium enhancement at 7T to image rats with reperfused acute myocardial infarction
Expressions of ECE-CYC2 clade genes relating to abortion of both dorsal and ventral stamens in Opithandra (Gesneriaceae)
<p>Abstract</p> <p>Background</p> <p>ECE-CYC2 clade genes known in patterning floral dorsoventral asymmetry (zygomorphy) in <it>Antirrhinum majus </it>are conserved in the dorsal identity function including arresting the dorsal stamen. However, it remains uncertain whether the same mechanism underlies abortion of the ventral stamens, an important morphological trait related to evolution and diversification of zygomorphy in Lamiales <it>sensu lato</it>, a major clade of predominantly zygomorphically flowered angiosperms. <it>Opithandra </it>(Gesneriaceae) is of particular interests in addressing this question as it is in the base of Lamiales <it>s.l</it>., an early representative of this type zygomorphy.</p> <p>Results</p> <p>We investigated the expression patterns of four ECE-CYC2 clade genes and two putative target <it>cyclinD3 </it>genes in <it>Opithandra </it>using RNA <it>in situ </it>hybridization and RT-PCR. <it>OpdCYC </it>gene expressions were correlated with abortion of both dorsal and ventral stamens in <it>Opithandra</it>, strengthened by the negatively correlated expression of their putative target <it>OpdcyclinD3 </it>genes. The complement of <it>OpdcyclinD3 </it>to <it>OpdCYC </it>expressions further indicated that <it>OpdCYC </it>expressions were related to the dorsal and ventral stamen abortion through negative effects on <it>OpdcyclinD3 </it>genes.</p> <p>Conclusion</p> <p>These results suggest that ECE-CYC2 clade TCP genes are not only functionally conserved in the dorsal stamen repression, but also involved in arresting ventral stamens, a genetic mechanism underlying the establishment of zygomorphy with abortion of both the dorsal and ventral stamens evolved in angiosperms, especially within Lamiales <it>s.l</it>.</p
Inelastic Final-State Interactions of Processes
We study the final-state interactions in decays through processes where the inelastic rescattering occurs via single pion
exchange. The next-to-leading order low energy effective Hamiltonian and BSW
model are used to evaluate the weak transition matrix elements and the
final-state interactions. We found that the final-state interaction effects in
processes are significant. The Fleischer-Mannel
relation about the CKM angle may be significantly modified.Comment: Latex, 14 pages, with 1 figures and 2 table
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