3,244 research outputs found
Maximization of capacity and p-norms for some product channels
It is conjectured that the Holevo capacity of a product channel \Omega
\otimes \Phi is achieved when product states are used as input. Amosov, Holevo
and Werner have also conjectured that the maximal p-norm of a product channel
is achieved with product input states. In this paper we establish both of these
conjectures in the case that \Omega is arbitrary and \Phi is a CQ or QC channel
(as defined by Holevo). We also establish the Amosov, Holevo and Werner
conjecture when \Omega is arbitrary and either \Phi is a qubit channel and p=2,
or \Phi is a unital qubit channel and p is integer. Our proofs involve a new
conjecture for the norm of an output state of the half-noisy channel I \otimes
\Phi, when \Phi is a qubit channel. We show that this conjecture in some cases
also implies additivity of the Holevo capacity
Redshifts of the Gravitational Lenses MG1131+0456 and B1938+666
The redshifts of the gravitational lens galaxies in MG1131+0456 and B1938+666
are 0.844 and 0.881 respectively. Both are early-type galaxies lying at the
redshifts predicted by assuming that they are early-type galaxies with old
stellar populations lying on the fundamental plane. We also find evidence for a
foreground group of galaxies at z=0.343 near MG1131+0456. The source redshifts
are predicted to be >1.8 in both systems, but they are so red that infrared
spectra will be required to determine their redshifts.Comment: 10 pages, AASTeX Latex, including 1 JPEG and 2 postscript figures,
submitted to Astronomical Journal Minor typos fixe
Qubit Channels Can Require More Than Two Inputs to Achieve Capacity
We give examples of qubit channels that require three input states in order
to achieve the Holevo capacity.Comment: RevTex, 5 page, 4 figures
Program Peningkatan Kemampuan Guru Dalam Pembelajaran Bahasa Jawa Di SD Patemon 01 Dan SD Sekaran 01 Kecamatan Gunungpati Kota Semarang
Learning Javanese language has been starting on since a long time, but still there are some problems found in the field. Problems when learning Javanese language that occur in SD Patemon 01 and SD Sekaran 01, District Gunungpati, Semarang are (1) low capacity of the teachers in creating computer-based learning media, (2) lack of language skills of the teachers in using Javanese language variety of manners, and (3) frequent occurrence of errors in the assessment of learning Javanese language. In connection with these conditions, devotee team tried to be facilitators to the problems faced by teachers in SD Patemon 01 and SD Sekaran 01 by conducting science and technology activities for the Community (IbM). IbM program implementation used workshop model with a variety of methods, such as lecturing, demonstrations, direct practice, frequently asked questions and assignments. The results of this IbM program are capacity building of teachers in making computers-based learning media for Javanese language, improving the competence of teachers in terms of manners of Javanese language skills, and increaseing understanding of Javanese language learning assessment. The increase was indicated from abilities\u27 score of the teachers before and after the IbM program. The ability of teachers in terms of making computer-based instructional media increased significantly, ie 16.9%. Competence of teachers in terms of unggah-ungguh based on Javanese language, especially in speaking skills manners increased 6.3%. The ability of teachers in terms of understanding of the Java language learning assessment increased 9.7%
GPS Rates of Vertical Bedrock Motion Suggest Late Holocene Ice-Sheet Readvance in a Critical Sector of East Antarctica
We investigate present-day bedrock vertical motion using new GPS timeseries from the Totten-Denman glacier region of East Antarctica (∼77-120°E) where models of glacial isostatic adjustment (GIA) disagree, glaciers are likely losing mass, and few data constraints on GIA exist. We show that varying surface mass balance loading (SMBL) is a dominant signal, contributing random-walk-like noise to GPS timeseries across Antarctica. In the study region, it induces site velocity biases of up to ∼+1 mm/yr over 2010-2020. After correcting for SMBL displacement and GPS common mode error, subsidence is evident at all sites aside from the Totten Glacier region where uplift is ∼1.5 mm/yr. Uplift near the Totten Glacier is consistent with late Holocene ice retreat while the widespread subsidence further west suggests possible late Holocene readvance of the region’s ice sheet, in broad agreement with limited glacial geological data and highlighting the need for sampling beneath the current ice sheet
Depletion of enteric bacteria diminishes leukocyte infiltration following doxorubicin-induced small intestinal damage in mice
While enteric bacteria have been shown to play a critical role in other forms of intestinal damage, their role in mediating the response to the chemotherapeutic drug Doxorubicin (Doxo) is unclear. In this study, we used a mouse model of intestinal bacterial depletion to evaluate the role enteric bacteria play in mediating Doxo-induced small intestinal damage and, more specifically, in mediating chemokine expression and leukocyte infiltration following Doxo treatment. An understanding of this pathway may allow for development of intervention strategies to reduce chemotherapy-induced small intestinal damage
What is on Tap? The Role of Spin in Compact Objects and Relativistic Jets
We examine the role of spin in launching jets from compact objects across the
mass scale. Our work includes a total of 37 Seyferts, 11 stellar-mass black
holes, and 13 neutron stars. We find that when the Seyfert reflection lines are
modeled with Gaussian line features (a crude proxy for inner disk radius and
therefore spin), only a slight inverse correlation is found between the
Doppler-corrected radio luminosity at 5 GHz (a proxy for jet power) and line
width. When the Seyfert reflection features are fit with
relativistically-blurred disk reflection models that measure spin, there is a
tentative positive correlation between the Doppler-corrected radio luminosity
and the spin measurement. Further, when we include stellar-mass black holes in
the sample, to examine the effects across the mass scale, we find a slightly
stronger correlation with radio luminosity per unit mass and spin, at a
marginal significance (2.3 sigma confidence level). Finally, when we include
neutron stars, in order to probe lower spin values, we find a positive
correlation (3.3 sigma confidence level) between radio luminosity per unit mass
and spin. Although tentative, these results suggest that spin may have a role
in determining the jet luminosity. In addition, we find a slightly more
significant correlation (4.4 sigma confidence level) between radio luminosity
per Bolometric luminosity and spin, using our entire sample of black holes and
neutrons stars. Again, although tentative, these relations point to the
possibility that the mass accretion rate, i.e. Bolometric luminosity, is also
important in determining the jet luminosity, in addition to spin. Our analysis
suggests that mass accretion rate and disk or coronal magnetic field strength
may be the "throttle" in these compact systems, to which the Eddington limit
and spin may set the maximum jet luminosity that can be achieved.Comment: 14 pages, 13 Figures, ApJ Accepte
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