2,860 research outputs found
Early redox activities modulate Xenopus tail regeneration.
Redox state sustained by reactive oxygen species (ROS) is crucial for regeneration; however, the interplay between oxygen (O2), ROS and hypoxia-inducible factors (HIF) remains elusive. Here we observe, using an optic-based probe (optrode), an elevated and steady O2 influx immediately upon amputation. The spatiotemporal O2 influx profile correlates with the regeneration of Xenopus laevis tadpole tails. Inhibition of ROS production but not ROS scavenging decreases O2 influx. Inhibition of HIF-1α impairs regeneration and stabilization of HIF-1α induces regeneration in the refractory period. In the regeneration bud, hypoxia correlates with O2 influx, ROS production, and HIF-1α stabilization that modulate regeneration. Further analyses reveal that heat shock protein 90 is a putative downstream target of HIF-1α while electric current reversal is a de facto downstream target of HIF-1α. Collectively, the results show a mechanism for regeneration via the orchestration of O2 influx, ROS production, and HIF-1α stabilization
Synthesis and structure of the inclusion complex {NdQ[5]K@Q[10](H₂O)4}·4NO₃·20H₂O
Heating a mixture of Nd(NO₃)₃·6H₂O, KCl, Q[10] and Q[5] in HCl for 10 min affords the inclusion complex {NdQ[5]K@Q[10](H₂O)₄}·4NO₃·20H₂O. The structure of the inclusion complex has been investigated by single crystal X-ray diffraction and by X-ray Photoelectron spectroscopy (XPS)
Atomically thin mononitrides SiN and GeN: new two-dimensional semiconducting materials
Low-dimensional Si-based semiconductors are unique materials that can both
match well with the Si-based electronics and satisfy the demand of
miniaturization in modern industry. Owing to the lack of such materials, many
researchers put their efforts into this field. In this work, employing a swarm
structure search method and density functional theory, we theoretically predict
two-dimensional atomically thin mononitrides SiN and GeN, both of which present
semiconducting nature. Furthermore study shows that SiN and GeN behave as
indirect band gap semiconductors with the gap of 1.75 and 1.20 eV,
respectively. The ab initio molecular dynamics calculation tells that both two
mononitrides can exist stably even at extremely high temperature of 2000 K.
Notably, electron mobilities are evaluated as 0.888x
and 0.413x for SiN and GeN, respectively. The present
work expands the family of low-dimensional Si-based semiconductors.Comment: arXiv admin note: text overlap with arXiv:1703.0389
Triply heavy tetraquark states with the configuration
In the framework of the color-magnetic interaction, we systematically
investigate the mass splittings of the tetraquark states and
estimated their rough masses in this work. These systems include the explicitly
exotic states and and the hidden exotic
states , , , and
. If a state around the estimated mass region could be
observed, its nature as a genuine tetraquark is favored. The strong decay
patterns shown here will be helpful to the experimental search for these exotic
states.Comment: 14 pages, 3 figures and 9 tables. Accepted by Eur. Phys. J.
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