2,505 research outputs found
Direct Microlensing-Reverberation Observations of the Intrinsic magnetic Structure of AGN in Different Spectral States: A Tale of Two Quasars
We show how direct microlensing-reverberation analysis performed on two
well-known Quasars (Q2237 - The Einstein Cross and Q0957 - The Twin) can be
used to observe the inner structure of two quasars which are in significantly
different spectral states. These observations allow us to measure the detailed
internal structure of quasar Q2237 in a radio quiet high-soft state, and
compare it to quasar Q0957 in a radio loud low-hard state. We find that the
observed differences in the spectral states of these two quasars can be
understood as being due to the location of the inner radii of their accretion
disks relative to the co-rotation radii of rotating intrinsically magnetic
supermassive compact objects in the centers of these quasars.Comment: 26 page manuscript with 2 tables and 2 figures, submitted to
Astronomical Journa
Anorexia/Bulimia, Transcendence, and the Potential Impact of Romanticized/Sexualized Death Imagery
Presented November 10, 2014. Papers presented for the Center for the Study of Ethics in Society Western Michigan Universit
Tritium release of Li₄SiO₄, Li₂O and beryllium and chemical compatibility of beryllium with Li₄SiO₄, Li₂O and steel (SIBELIUS irradiation)
Tritium release and gamma activity of various lithium ceramics irradiated by fast and thermal neutrons (COMPLIMENT experiment)
Hamiltonian Formulation of Two Body Problem in Wheeler-Feynman electrodynamics
A Hamiltonian formulation for the classical problem of electromagnetic
interaction of two charged relativistic particles is found.Comment: 22 pages, 8 Uuencoded Postscript figure
Acid-sensing (proton-gated) ion channels (ASICs) (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database
Acid-sensing ion channels (ASICs, nomenclature as agreed by NC-IUPHAR [35]) are members of a Na+ channel superfamily that includes the epithelial Na+ channel (ENaC), the FMRF-amide activated channel (FaNaC) of invertebrates, the degenerins (DEG) of Caenorhabitis elegans, channels in Drosophila melanogaster and 'orphan' channels that include BLINaC [46] and INaC [47] that have also been named BASICs, for bile acid-activated ion channels [58]. ASIC subunits contain two TM domains and assemble as homo- or hetero-trimers [34, 31, 5] to form proton-gated, voltage-insensitive, Na+ permeable, channels (reviewed in [33, 57]). Splice variants of ASIC1 [termed ASIC1a (ASIC, ASICα, BNaC2α) [55], ASIC1b (ASICβ, BNaC2β) [13] and ASIC1b2 (ASICβ2) [50]; note that ASIC1a is also permeable to Ca2+] and ASIC2 [termed ASIC2a (MDEG1, BNaC1α, BNC1α) [45, 56, 30] and ASIC2b (MDEG2, BNaC1β) [40]] have been cloned. Unlike ASIC2a (listed in table), heterologous expression of ASIC2b alone does not support H+-gated currents. A third member, ASIC3 (DRASIC, TNaC1) [54], has been identified. A fourth mammalian member of the family (ASIC4/SPASIC) does not support a proton-gated channel in heterologous expression systems and is reported to downregulate the expression of ASIC1a and ASIC3 [1, 32, 24, 39]. ASIC channels are primarily expressed in central and peripheral neurons including nociceptors where they participate in neuronal sensitivity to acidosis. They have also been detected in taste receptor cells (ASIC1-3), photoreceptors and retinal cells (ASIC1-3), cochlear hair cells (ASIC1b), testis (hASIC3), pituitary gland (ASIC4), lung epithelial cells (ASIC1a and -3), urothelial cells, adipose cells (ASIC3), vascular smooth muscle cells (ASIC1-3), immune cells (ASIC1,-3 and -4) and bone (ASIC1-3). A neurotransmitter-like function of protons has been suggested, involving postsynaptically located ASICs of the CNS in functions such as learning and fear perception [25, 36, 63], responses to focal ischemia [59] and to axonal degeneration in autoimmune inflammation in a mouse model of multiple sclerosis [29], as well as seizures [64] and pain [19, 20, 10, 22]. Heterologously expressed heteromultimers form ion channels with differences in kinetics, ion selectivity, pH- sensitivity and sensitivity to blockers that resemble some of the native proton activated currents recorded from neurones [40, 3, 28, 8]
Removing black-hole singularities with nonlinear electrodynamics
We propose a way to remove black hole singularities by using a particular
nonlinear electrodynamics Lagrangian that has been recently used in various
astrophysics and cosmological frameworks. In particular, we adapt the
cosmological analysis discussed in a previous work to the black hole physics.
Such analysis will be improved by applying the Oppenheimer-Volkoff equation to
the black hole case. At the end, fixed the radius of the star, the final
density depends only on the introduced quintessential density term
and on the mass.Comment: In this last updated version we correct two typos which were present
in Eqs. (21) and (22) in the version of this letter which has been published
in Mod. Phys. Lett. A 25, 2423-2429 (2010). In the present version, both of
Eqs. (21) and (22) are dimensionally and analytically correc
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