20,724 research outputs found
Human Resources: Key to Competitive Advantage
[Excerpt] As difficult as it may be and as fuzzy as it may turn out, we all must invest in an attempt to peer into the future to discern what implications it has for our human resources. It is not a precise effort, and it certainly can be challenged from many quarters; however, it is not only noble, but may prove to be extremely worthwhile for a competitive firm. As with almost every organization activity, the competitive world makes a paradigm shift inevitable for the human resource function. Understanding the nature of that shift and how to implement meaningful change are the fundamental questions for us all
On transcendental numbers: new results and a little history
Attempting to create a general framework for studying new results on
transcendental numbers, this paper begins with a survey on transcendental
numbers and transcendence, it then presents several properties of the
transcendental numbers and , and then it gives the proofs of new
inequalities and identities for transcendental numbers. Also, in relationship
with these topics, we study some implications for the theory of the Yang-Baxter
equations, and we propose some open problems.Comment: 8 page
Esthetic rehabilitation with ultra-thin ceramic veneers and direct mock-up in the treatment of dental erosion – Case report
Indexación: Scopus.Dental erosion is a high prevalence condition characterized by the loss of dental substance due to chemical agents. It can also be associated with �physical wear, affecting function and aesthetics. Ceramic veneers can provide effective solutions to patients affected by erosive disorders, by means of an indirect approach and minimal intervention. Recent advances in cementation techniques and ceramic materials have allowed their use in reduced thicknesses, known as "dental contact lenses" or "ultra-thin veneers". They contribute significantly to the preservation of the dental structures, having excellent models or mock ups in order to preview the final outcome. Case: The aim of this report is to communicate the use of this technique for the treatment and successful 12-months follow-up of a patient affected by dental erosion of the maxillary central incisors. Special interest was placed on direct mock-up, which is a simple technique not requiring laboratory steps. Luting of the lithium disilicate veneers was carried out with a light-curing resin cement and try-in pastes, yielding a very satisfactory result. Conclusion: Diagnosis and early treatment of this disorder allows the application of conservative techniques, such as ultra-thin veneers, which are seen as a promising alternative treatment to full coverage restorations and traditional ceramic veneers. © 2018, Universidad de Concepcion. All rights reserved.http://joralres.com/index.php/JOR/article/view/481/45
Unparticle contribution to the hydrogen atom ground state energy
In the present work we study the effect of unparticle modified static
potentials on the energy levels of the hydrogen atom. By using
Rayleigh-Schr\"odinger perturbation theory, we obtain the energy shift of the
ground state and we compare it with experimental data. Bounds on the unparticle
energy scale as a function of the scaling dimension
and the coupling constant are derived. We show that
there exists a parameter region where bounds on are
stringent, signalling that unparticles could be tested in atomic physics
experiments.Comment: 11 pages, 3 figure
Star Integrals, Convolutions and Simplices
We explore single and multi-loop conformal integrals, such as the ones
appearing in dual conformal theories in flat space. Using Mellin amplitudes, a
large class of higher loop integrals can be written as simple
integro-differential operators on star integrals: one-loop -gon integrals in
dimensions. These are known to be given by volumes of hyperbolic simplices.
We explicitly compute the five-dimensional pentagon integral in full generality
using Schl\"afli's formula. Then, as a first step to understanding higher
loops, we use spline technology to construct explicitly the hexagon and
octagon integrals in two-dimensional kinematics. The fully massive hexagon
and octagon integrals are then related to the double box and triple box
integrals respectively. We comment on the classes of functions needed to
express these integrals in general kinematics, involving elliptic functions and
beyond.Comment: 23 page
Predicting the connectivity of primate cortical networks from topological and spatial node properties
The organization of the connectivity between mammalian cortical areas has
become a major subject of study, because of its important role in scaffolding
the macroscopic aspects of animal behavior and intelligence. In this study we
present a computational reconstruction approach to the problem of network
organization, by considering the topological and spatial features of each area
in the primate cerebral cortex as subsidy for the reconstruction of the global
cortical network connectivity. Starting with all areas being disconnected,
pairs of areas with similar sets of features are linked together, in an attempt
to recover the original network structure. Inferring primate cortical
connectivity from the properties of the nodes, remarkably good reconstructions
of the global network organization could be obtained, with the topological
features allowing slightly superior accuracy to the spatial ones. Analogous
reconstruction attempts for the C. elegans neuronal network resulted in
substantially poorer recovery, indicating that cortical area interconnections
are relatively stronger related to the considered topological and spatial
properties than neuronal projections in the nematode. The close relationship
between area-based features and global connectivity may hint on developmental
rules and constraints for cortical networks. Particularly, differences between
the predictions from topological and spatial properties, together with the
poorer recovery resulting from spatial properties, indicate that the
organization of cortical networks is not entirely determined by spatial
constraints
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