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Disease modelling using evolved discriminate function
Precocious diagnosis increases the survival time and patient quality of life. It is a binary classification, exhaustively studied in the literature. This paper innovates proposing the application of genetic programming to obtain a discriminate function. This function contains the disease dynamics used to classify the patients with as little false negative diagnosis as possible. If its value is greater than zero then it means that the patient is ill, otherwise healthy. A graphical representation is proposed to show the influence of each dataset attribute in the discriminate function. The experiment deals with Breast Cancer and Thrombosis & Collagen diseases diagnosis. The main conclusion is that the discriminate function is able to classify the patient using numerical clinical data, and the graphical representation displays patterns that allow understanding of the model
Inverse Neutrino-less Double Beta Decay Revisited: Neutrinos, Higgs Triplets and a Muon Collider
We revisit the process of inverse neutrino-less double beta decay (e e -> W
W) at future linear colliders. The cases of Majorana neutrino and Higgs triplet
exchange are considered. We also discuss the processes e mu -> W W and mu mu ->
W W, which are motivated by the possibility of muon colliders. For heavy
neutrino exchange and center-of-mass energies larger than 1 TeV, we show that
masses up to 10^6 (10^5) GeV could be probed for e-e and e-mu machines,
respectively. The stringent limits for mixing of heavy neutrinos with muons
render mu mu -> W W less promising, even though this process is not constrained
by limits from neutrino-less double beta decay. If Higgs triplets are
responsible for inverse neutrino-less double beta decay, observable signals are
only possible if a very narrow resonance is met. We also consider unitarity
aspects of the process in case both Higgs triplets and neutrinos are exchanged.
An exact see-saw relation connecting low energy data with heavy neutrino and
triplet parameters is found.Comment: 19 pages, 6 figure
and Spectra for Au+Au Collisions at = 200 GeV from STAR, PHENIX and BRAHMS in Comparison to Core-Corona Model Predictions
Based on results obtained with event generators we have launched the
core-corona model. It describes in a simplified way but quite successfully the
centrality dependence of multiplicity and of identified particles
observed in heavy-ion reaction at beam energies between = 17 GeV and
200 GeV. Also the centrality dependence of the elliptic flow, , for all
charged and identified particles could be explained in this model. Here we
extend this analysis and study the centrality dependence of single particle
spectra of and measured by the PHENIX, STAR and BRAHMS
collaborations. We find that also for these particles the analysis of the
spectra in the core-corona model suffers from differences in the data published
by the different experimental groups, notably for the pp collisions. As for
protons and for each experience the data agree well with the prediction
of the core-corona model but the value of the two necessary parameters depends
on the experiments. We show as well that the average momentum as a function of
the centrality depends in a very sensitive way on the particle species and may
be quite different for particles which have about the same mass. Therefore the
idea to interpret this centrality dependence as a consequence of a collective
expansion of the system, as done in blast way fits may be premature.Comment: Invited talk to the CPOD conference Dubna August 201
Phase transitions and the internal noise structure of nonlinear Schr\"odi nger equation solitons
We predict phase-transitions in the quantum noise characteristics of systems
described by the quantum nonlinear Schr\"odinger equation, showing them to be
related to the solitonic field transition at half the fundamental soliton
amplitude. These phase-transitions are robust with respect to Raman noise and
scattering losses. We also describe the rich internal quantum noise structure
of the solitonic fields in the vicinity of the phase-transition. For optical
coherent quantum solitons, this leads to the prediction that eliminating the
peak side-band noise due to the electronic nonlinearity of silica fiber by
spectral filtering leads to the optimal photon-number noise reduction of a
fundamental soliton.Comment: 10 pages, 5 figure
Test of the Universality of Naive-time-reversal-odd Fragmentation Functions
We investigate the ''spontaneous'' hyperon transverse polarization in
annihilation and semi-inclusive deep inelastic scattering processes as
a test of the universality of the naive-time-reversal-odd transverse momentum
dependent fragmentation functions. We find that universality implies definite
sign relations among various observables. This provides a unique opportunity to
study initial/final state interaction effects in the fragmentation process and
test the associated factorization.Comment: 4 pages, 3 figure
Probing Gluonic Spin-Orbit Correlations in Photon Pair Production
We consider photon pair production in hadronic collisions at large mass and
small transverse momentum of the pair, assuming that factorization in terms of
transverse momentum dependent parton distributions applies. The unpolarized
cross section is found to have azimuthal angular dependencies that are
generated by a gluonic version of the Boer-Mulders function. In addition, the
single-transversely polarized cross section is sensitive to the gluon Sivers
function. We present simple numerical estimates for the Boer-Mulders and Sivers
effects in diphoton production at RHIC and find that the process would offer
unique opportunities for exploring transverse momentum dependent gluon
distributions.Comment: 5 pages, 2 figures, minor changes, final version, to be published in
PR
Mid-Cretaceous (Cenomanian) snakes from Wadi Abu Hashim, Sudan: the earliest snake assemblage
The Cenomanian (mid-Cretaceous) beds at Wadi Abu Hashim (Sudan) have yielded a snake assemblage that is very rich and diverse for its geological age. It is by far the oldest known snake fauna. As the assignment of the hitherto earliest presumed snake (Barremian) to the Serpentes may now be questioned, this diverse fauna is only slightly younger than the earliest certain appearance of snakes (late Albian). The fauna is a surprising mixture of very primitive and comparatively advanced snakes. It includes two forms belonging to the lapparentophiid-grade of snakes (â lapparentophiid-grade snake A â and â lapparentophiid-grade snake B â), an indeterminate Madtsoiidae, a possible Palaeophiidae, the aniliid Coniophis dabiebus sp. nov., Coniophis cf. C. dabiebus, the nigerophiid Nubianophis afaahus gen. et sp. nov., Nubianophis cf. N. afaahus, the russellophiid Krebsophis thobanus gen. et sp. nov., a Colubroidea incertae sedis (indeterminate family), and two indeterminate snakes. In sum, at least nine species, perhaps twelve, are present. They represent at least seven families: at least one family of lapparentophiid-grade (?Lapparentophiidae), Madtsoiidae, ?Palaeophiidae, Aniliidae, Nigerophiidae, Russellophiidae, and an indeterminate colubroid family. The presence of colubroid snakes (Russellophiidae and an indeterminate family) as early as the mid-Cretaceous is especially unexpected. It may be inferred from phylogenies that the higher taxa of snakes (Anilioidea, Booidea, Acrochordoidea, Colubroidea, and obviously Scolecophidia) were already present during mid-Cretaceous times. The diversity of this fauna, coupled with the presence of advanced forms (colubroids), suggest that the origin of snakes markedly antedates the Cenomanian. Africa played an important role in the early radiation and, probably, in the origin of snakes.The Council's Research Committe, University of the Witwatersrand; National Science Foundatio
High-magnetic field phase diagram and failure of magnetic Gr\"uneisen scaling in LiFePO
We report the magnetic phase diagram of single-crystalline LiFePO in
magnetic fields up to 58~T and present a detailed study of magneto-elastic
coupling by means of high-resolution capacitance dilatometry. Large anomalies
at \tn\ in the thermal expansion coefficient imply pronounced
magneto-elastic coupling. Quantitative analysis yields the magnetic Gr\"uneisen
parameter ~mol/J. The positive
hydrostatic pressure dependence ~K/GPa is dominated
by uniaxial effects along the -axis. Failure of Gr\"uneisen scaling below
~K, i.e., below the peak temperature in the magneto-electric
coupling coefficient [\onlinecite{toft2015anomalous}], implies several
competing degrees of freedom and indicates relevance of recently observed
hybrid excitations~[\onlinecite{yiu2017hybrid}]. A broad and strongly
magnetic-field-dependent anomaly in in this temperature regime
highlight the relevance of structure changes. Upon application of magnetic
fields -axis, a pronounced jump in the magnetisation implies
spin-reorientation at ~T as well as a precursing phase at 29~T
and ~K. In a two-sublattice mean-field model, the saturation field
~T enables the determination of the effective
antiferromagnetic exchange interaction ~meV as well as
the anisotropies ~meV and ~meV
Convergence rates in expectation for Tikhonov-type regularization of Inverse Problems with Poisson data
In this paper we study a Tikhonov-type method for ill-posed nonlinear
operator equations \gdag = F(
ag) where \gdag is an integrable,
non-negative function. We assume that data are drawn from a Poisson process
with density t\gdag where may be interpreted as an exposure time. Such
problems occur in many photonic imaging applications including positron
emission tomography, confocal fluorescence microscopy, astronomic observations,
and phase retrieval problems in optics. Our approach uses a
Kullback-Leibler-type data fidelity functional and allows for general convex
penalty terms. We prove convergence rates of the expectation of the
reconstruction error under a variational source condition as both
for an a priori and for a Lepski{\u\i}-type parameter choice rule
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