11,083 research outputs found
Electron-impact excitation of diatomic hydride cations I: HeH, CH, ArH
{\bf R}-matrix calculations combined with the adiabatic nuclei approximation
are used to compute electron-impact rotiational excitation rates for three
closed-shell diatomic cations, HeH, CH, ArH. Comparisons with
previous studies show that an improved treatment of threshold effects leads to
significant changes in the low temperature rates, furthermore the new
calculations suggest that excitation of CH is dominated by
transitions as is expected for cations with a large dipole moment. A model for
ArH excitation in the Crab Nebula is presented which gives results
consistent with the observations for electron densities in the range ~cm.Comment: MNRAS submitted 7 pages, 9 figure
Detection of flour or farina from Triticum aestivum in macaroni by starch-gel electrophoresis of water-soluble proteins
A water-soluble protein component, A, has been found which appears without exception at a higher concentration in Triticum aestivum than in T. durum. Quantitation of A is achieved by referring the height of densitogram peak A to the height of peak B, which corresponds to a second component that is present in all varieties studied from both species. Extreme valúes of peak height ratio (PHR) in both species are tentatively established. On the basis of these valúes, the máximum and minimum possible contents of T. aestivum in a mixture are expressed as a function of PHR. All the varieties of T. aestivum studied are detected when they contribute more than 60% to the mixture. In over 90% of all possible binary combinations between varieties of T. aestivum and T. durum, the máximum proportion of undetected T. aestivum has been 30%
A seven square degrees survey for galaxy-scale gravitational lenses with the HST imaging archive
We present the results of a visual search for galaxy-scale gravitational
lenses in nearly 7 square degrees of Hubble Space Telescope (HST) images. The
dataset comprises the whole imaging data ever taken with the Advanced Camera
for Surveys (ACS) in the filter F814W (I-band) up to August 31st, 2011, i.e.
6.03 square degrees excluding the field of the Cosmic Evolution Survey (COSMOS)
which has been the subject of a separate visual search. In addition, we have
searched for lenses in the whole Wide Field Camera 3 (WFC3) near-IR imaging
dataset in all filters (1.01 square degrees) up to the same date. Our primary
goal is to provide a sample of lenses with a broad range of different
morphologies and lens-source brightness contrast in order estimate a lower
limit to the number of galaxy-scale strong lenses in the future Euclid survey
in its VIS band. Our criteria to select lenses are purely morphological as we
do not use any colour or redshift information.The final candidate selection is
very conservative hence leading to a nearly pure but incomplete sample. We find
49 new lens candidates: 40 in the ACS images and 9 in the WFC3 images. Out of
these, 16 candidates are secure lenses owing to their striking morphology, 21
more are very good candidates, and 12 more have morphologies compatible with
gravitational lensing but also compatible with other astrophysical objects. It
is therefore insensitive to cosmic variance and allows to estimate the number
of galaxy-scale strong lenses on the sky for a putative survey depth, which is
the main result of the present work. Because of the incompleteness of the
sample, the estimated lensing rates should be taken as lower limits. Using
these, we anticipate that a 15 000 square degrees space survey such as Euclid
will find at least 60 000 galaxy-scale strong lenses down to a limiting AB
magnitude of I = 24.5 (10-sigma) or I = 25.8 (3-sigma).Comment: 13 pages, 12 figures, Accepted for publication in MNRA
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Bodhidharma as Textual and Religious Paradigm
A structural analysis of the life of Bodhidharma, the legendary founder of Chan/Zen Buddhism
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In the Quiet of the Monastery: Buddhist Controversies over Quietism
The Christian notion of 'Quietism' has sometimes been used in the West to criticize Buddhism. Within Buddhism itself (in particular Chan or Zen), a similar criticism has prevailed at times. This essay examines the history of such controversies
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Kegon and Dragons: A Mythological Approach to Huayan Doctrine
A study of the relations between the doctrine of Huayan Buddhism and the legends surrounding some of the Huayan school patriarchs in China, Korea, and Japan
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The Buddhist Icon and the Modern Gaze
A discussion of theoretical issues concerning the modern reception of Buddhist art
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Space and Place in Chinese Religious Traditions
A discussion of spatial metaphors and local cults in Chan (Zen) Buddhism
Many parameter Hoelder perturbation of unbounded operators
If is a -mapping, for , having
as values unbounded self-adjoint operators with compact resolvents and common
domain of definition, parametrized by in an (even infinite dimensional)
space, then any continuous (in ) arrangement of the eigenvalues of is
indeed in .Comment: LaTeX, 4 pages; The result is generalized from Lipschitz to Hoelder.
Title change
Entropy of complex relevant components of Boolean networks
Boolean network models of strongly connected modules are capable of capturing
the high regulatory complexity of many biological gene regulatory circuits. We
study numerically the previously introduced basin entropy, a parameter for the
dynamical uncertainty or information storage capacity of a network as well as
the average transient time in random relevant components as a function of their
connectivity. We also demonstrate that basin entropy can be estimated from
time-series data and is therefore also applicable to non-deterministic networks
models.Comment: 8 pages, 6 figure
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