3,413 research outputs found
First Digit Distribution of Hadron Full Width
A phenomenological law, called Benford's law, states that the occurrence of
the first digit, i.e., , of numbers from many real world sources is
not uniformly distributed, but instead favors smaller ones according to a
logarithmic distribution. We investigate, for the first time, the first digit
distribution of the full widths of mesons and baryons in the well defined
science domain of particle physics systematically, and find that they agree
excellently with the Benford distribution. We also discuss several general
properties of Benford's law, i.e., the law is scale-invariant, base-invariant,
and power-invariant. This means that the lifetimes of hadrons follow also
Benford's law.Comment: 8 latex pages, 4 figures, final version in journal publicatio
Competitiveness and sustainability: can ‘smart city regionalism’ square the circle?
Increasingly, the widely established, globalisation-driven agenda of economic competitiveness meets a growing concern with sustainability. Yet, the practical and conceptual co-existence—or fusion—of these two agendas is not always easy. This includes finding and operationalising the ‘right’ scale of governance, an important question for the pursuit of the distinctly transscalar nature of these two policy fields. ‘New regionalism’ has increasingly been discussed as a pragmatic way of tackling the variable spatialities associated with these policy fields and their changing articulation. This paper introduces ‘smart (new) city-regionalism’, derived from the principles of smart growth and new regionalism, as a policy-shaping mechanism and analytical framework. It brings together the rationales, agreed principles and legitimacies of publicly negotiated polity with collaborative, network-based and policy-driven spatiality. The notion of ‘smartness’, as suggested here as central feature, goes beyond the implicit meaning of ‘smart’ as in ‘smart growth’. When introduced in the later 1990s the term embraced a focus on planning and transport. Since then, the adjective ‘smart’ has become used ever more widely, advocating innovativeness, participation, collaboration and co-ordination. The resulting ‘smart city regionalism’ is circumscribed by the interface between the sectorality and territoriality of policy-making processes. Using the examples of Vancouver and Seattle, the paper looks at the effects of the resulting specific local conditions on adopting ‘smartness’ in the scalar positioning of policy-making
Positronium Hyperfine Splitting in Non-commutative Space at the Order
We obtain positronium Hyperfine Splitting owing to the non-commutativity of
space and show that, in the leading order, it is proportional to where, is the parameter of non-commutativity. It is also
shown that spatial non-commutativity splits the spacing between triplet
excited levels which provides an experimental test on
the non-commutativity of space.Comment: 7 pages, 2 figures, to appear in Phys. Rev.
Connection Between Type A and E Factorizations and Construction of Satellite Algebras
Recently, we introduced a new class of symmetry algebras, called satellite
algebras, which connect with one another wavefunctions belonging to different
potentials of a given family, and corresponding to different energy
eigenvalues. Here the role of the factorization method in the construction of
such algebras is investigated. A general procedure for determining an so(2,2)
or so(2,1) satellite algebra for all the Hamiltonians that admit a type E
factorization is proposed. Such a procedure is based on the known relationship
between type A and E factorizations, combined with an algebraization similar to
that used in the construction of potential algebras. It is illustrated with the
examples of the generalized Morse potential, the Rosen-Morse potential, the
Kepler problem in a space of constant negative curvature, and, in each case,
the conserved quantity is identified. It should be stressed that the method
proposed is fairly general since the other factorization types may be
considered as limiting cases of type A or E factorizations.Comment: 20 pages, LaTeX, no figure, to be published in J. Phys.
Input-Output Relations in Optical Cavities: a Simple Point of View
In this work we present a very simple approach to input-output relations in
optical cavities, limiting ourselves to one- and two-photon states of the
field.
After field quantization, we derive the non-unitary transformation between
{\em Inside} and {\em Outside} annihilation and creation operators. Then we
express the most general two-photon state generated by {\em Inside} creation
operators, through base states generated by {\em Outside} creation operators.
After renormalization of coefficients of inside two-photon state, we calculate
the outside photon-number probability distribution in a general case. Finally
we treat with some detail the single mode and symmetrical cavity case.Comment: 34 pages, 5 figures jpg, LaTe
Generalized Morse Potential: Symmetry and Satellite Potentials
We study in detail the bound state spectrum of the generalized Morse
potential~(GMP), which was proposed by Deng and Fan as a potential function for
diatomic molecules. By connecting the corresponding Schr\"odinger equation with
the Laplace equation on the hyperboloid and the Schr\"odinger equation for the
P\"oschl-Teller potential, we explain the exact solvability of the problem by
an symmetry algebra, and obtain an explicit realization of the latter
as . We prove that some of the generators
connect among themselves wave functions belonging to different GMP's (called
satellite potentials). The conserved quantity is some combination of the
potential parameters instead of the level energy, as for potential algebras.
Hence, belongs to a new class of symmetry algebras. We also stress
the usefulness of our algebraic results for simplifying the calculation of
Frank-Condon factors for electromagnetic transitions between rovibrational
levels based on different electronic states.Comment: 23 pages, LaTeX, 2 figures (on request). one LaTeX problem settle
The Effect of Steroid Treatment on Lipocortin Immunoreactivity of Rat Brain
Lipocortin-1, lipocortin-2 and lipocortin-5 were
immunohistochemically assessed in rats. Apart from animals receiving
no treatment, other animals received pretreatment with
methylprednisolone, or the 21-aminosteroid U-74389F. Whereas
Hpocortin immunoreactivity was absent in the greater part of the
brain in animals not pretreated with steroid (except in sporadic
microglial cells and choroid plexus), there was obvious
immunostaining of parenchymatous elements in steroid pretreated
animals. In the steroid pretreated animals lipocortin
immunoreactivity of the brain tissue may indicate local formation of
lipocortin under the influence of steroids that had entered the
tissue. The cellular elements which showed immunostaining included
meningeal cells, neurones, ependyma, oligodendroglia and capillary
endotheHum
The use of 0.01M phosphate buffered saline as detection buffer for Alere Determine® HIV rapid test in resource limited settings
Insufficient supply of manufacture’s buffers/diluents in relation to the number of strips per kit has been found to have negative impact on patients’ results. Some laboratories personnel tend to use diluents from other rapid tests manufacturers such as Bioline, Unigold as well as malaria rapid diagnostic test (MRDT). This study aimed at evaluating the use of 0.01M phosphate buffered saline (PBS) as detection buffer for Alere Determine® HIV rapid test. This study was carried out at Bugando School of Medicine in Mwanza, Tanzania. A total of 300 whole blood specimens; 150 HIV positive specimens from patients attending Care and Treatment Centreand 150 HIV negative specimens were retested for HIV status using Alere Determine® HIV rapid test employing normal Alere buffer and 0.01M PBS as buffer.Of the total specimens tested; 150 (100%) of HIV positive were positive by using both Alere buffer and 0.01M PBS while 150(100%) of HIV negative samples were negative by both Alere Determine® and 0.01M PBS. The agreement between 0.01M PBS and Alere Determine® buffer was 100%. The value of kappa indicates perfect agreement between 0.01M PBS and Alere Determine® buffer (100%). A 0.01M PBS is recommended as alternative detection buffer for Alere Determine® in cases of insufficient supply. Further investigation to evaluate the suitable buffer for other rapid tests for HIV and other diseases is recommended especially in resource limited settings.
Asymmetric Fluid Criticality I: Scaling with Pressure Mixing
The thermodynamic behavior of a fluid near a vapor-liquid and, hence,
asymmetric critical point is discussed within a general ``complete'' scaling
theory incorporating pressure mixing in the nonlinear scaling fields as well as
corrections to scaling. This theory allows for a Yang-Yang anomaly in which
\mu_{\sigma}^{\prime\prime}(T), the second temperature derivative of the
chemical potential along the phase boundary, diverges like the specific heat
when T\to T_{\scriptsize c}; it also generates a leading singular term,
|t|^{2\beta}, in the coexistence curve diameter, where t\equiv
(T-T_{\scriptsize c}) /T_{\scriptsize c}. The behavior of various special loci,
such as the critical isochore, the critical isotherm, the k-inflection loci, on
which \chi^{(k)}\equiv \chi(\rho,T)/\rho^{k} (with \chi = \rho^{2}
k_{\scriptsize B}TK_{T}) and C_{V}^{(k)}\equiv C_{V}(\rho,T)/\rho^{k} are
maximal at fixed T, is carefully elucidated. These results are useful for
analyzing simulations and experiments, since particular, nonuniversal values of
k specify loci that approach the critical density most rapidly and reflect the
pressure-mixing coefficient. Concrete illustrations are presented for the
hard-core square-well fluid and for the restricted primitive model electrolyte.
For comparison, a discussion of the classical (or Landau) theory is presented
briefly and various interesting loci are determined explicitly and illustrated
quantitatively for a van der Waals fluid.Comment: 21 pages in two-column format including 8 figure
- …