937 research outputs found
On the probability distribution of the stochastic saturation scale in QCD
It was recently noticed that high-energy scattering processes in QCD have a
stochastic nature. An event-by-event scattering amplitude is characterised by a
saturation scale which is a random variable. The statistical ensemble of
saturation scales formed with all the events is distributed according to a
probability law whose cumulants have been recently computed. In this work, we
obtain the probability distribution from the cumulants. We prove that it can be
considered as Gaussian over a large domain that we specify and our results are
confirmed by numerical simulations.Comment: 9 pages, 3 figures, misprints corrected, version to appear in PL
El concepto de "dominium" y "propietas" en los canonistas y moralistas desde el siglo XVI al XIX
Gluon production and diffraction in the dipole picture
Using the eikonal approximation, we show that inclusive gluon production is
related to the scattering of a gluon-gluon dipole while diffractive gluon
production in DIS is related to a two- dipole scattering amplitude.
Hence diffractive photon dissociation cross-sections are observables that
provide potential information on dipole correlations, which represent an open
issue in high-energy QCD.Comment: 4 pages, 2 figures, Proceedings of the 10th International Baryons
Conference (Baryons04), Ecole Polytechnique, Palaiseau, France, October 25-29
200
QCD traveling waves at non-asymptotic energies
Using consistent truncations of the BFKL kernel, we derive analytical
traveling-wave solutions of the Balitsky-Kovchegov saturation equation for both
fixed and running coupling. A universal parametrization of the ``interior'' of
the wave front is obtained and compares well with numerical simulations of the
original Balitsky-Kovchegov equation, even at non-asymptotic energies. Using
this universal parametrization, we find evidence for a traveling-wave pattern
of the dipole amplitude determined from the gluon distribution extracted from
deep inelastic scattering data.Comment: 10 pages, 5 figures, minor revision, version to appear in PL
The Balitsky-Kovchegov equation in full momentum space
We analyse the Balitsky-Kovchegov (BK) saturation equation in momentum space
and solve it numerically. We confirm that, in the limit where the transverse
momentum of the incident particle k is much bigger than the momentum transfer
q, the equation admits travelling-wave solutions. We extract the q dependence
of the saturation scale Q_s(Y) and verify that Q_s(Y=cste) scales as
max(q,Q_T), where Q_T is the scale caracterizing the target.Comment: 11 pages, 7 figures, minor corrections, version appeared in Nucl.
Phys.
Industrial applicability of advanced model/code-based V&V techniques for verifying program properties in embedded applications
International audienceThe constant and significant increase of computer power at low cost and many recent major technologicaladvances in program properties verification techniques show that designers and developers can now efficientlyand practically use proving techniques either at model or source code level.Those new V&V techniques convey major benefits to industrial sectors where software quality is at stake includingearly detection of errors (at specification, design and coding levels), and proof of absence of errors. Thosetechniques strengthen software application development process and minimize the likelihood of errors foundeither late or released in the field.The paper describes several advanced techniques for statically verifying dynamic properties of programsincluding logical, functional, run-time errors, how those techniques fit within current development processes andhow they may be used for monitoring software quality over time. The paper primarily applies to the developmentof embedded applications and demonstrates how the combined usage of techniques such as model-checking andabstract interpretation effectively handles industrial problems today
Validity of the Brunet-Derrida formula for the speed of pulled fronts with a cutoff
We establish rigorous upper and lower bounds for the speed of pulled fronts
with a cutoff. We show that the Brunet-Derrida formula corresponds to the
leading order expansion in the cut-off parameter of both the upper and lower
bounds. For sufficiently large cut-off parameter the Brunet-Derrida formula
lies outside the allowed band determined from the bounds. If nonlinearities are
neglected the upper and lower bounds coincide and are the exact linear speed
for all values of the cut-off parameter.Comment: 8 pages, 3 figure
Successful treatment of ciliary body medulloepithelioma with intraocular melphalan chemotherapy: a case report.
Intraocular medulloepithelioma is commonly treated with primary enucleation. Conservative treatment options include brachytherapy, local resection and/or cryotherapy in selected cases. We report for the first time the use of targeted chemotherapy to treat a ciliary body medulloepithelioma with aqueous and vitreous seeding.
A 17-month-old boy with a diagnosis of ciliary body medulloepithelioma with concomitant seeding and neovascular glaucoma in the right eye was seen for a second opinion after parental refusal of enucleation. Examination under anesthesia showed multiple free-floating cysts in the pupillary area associated with iris neovascularization and a subluxated and notched lens. Ultrasound biomicroscopy revealed a partially cystic mass adjacent to the ciliary body between the 5 and 9 o'clock meridians as well as multiple nodules in the posterior chamber invading the anterior vitreous inferiorly. Fluorescein angiography demonstrated peripheral retinal ischemia. Left eye was unremarkable. Diagnosis of intraocular medulloepithelioma with no extraocular invasion was confirmed and conservative treatment initiated with combined intracameral and intravitreal melphalan injections given according to the previously described safety-enhanced technique. Ciliary tumor and seeding totally regressed after a total of 3 combined intracameral (total dose 8.1 μg) and intravitreal (total dose 70 μg) melphalan injections given every 7-10 days. Ischemic retina was treated with cryoablation as necessary. Three years later, ab interno trabeculotomy followed by 360° gonioscopy-assisted transluminal trabeculotomy 6 months later was performed for uncontrolled intraocular pressure despite antihypertensive drugs combined to cyclophotocoagulation and 7 intravitreal anti-VEGF injections for recurrent iris neovascularization. Cataract was removed at the same operative time. The child has remained disease- and metastasis-free at a 5-year follow-up since the last melphalan injection (25-month follow-up after the combined lensectomy-trabeculotomy) with a controlled intraocular pressure under topical quadritherapy and a best corrected Snellen visual acuity of 0.08.
We report for the first time complete regression of a non-infiltrating ciliary body medulloepithelioma with seeding achieved with only a small number of intracameral and intravitreal melphalan injections. Concomitant secondary neovascular glaucoma and cataract needed appropriate management to allow long-term eye and vision preservation
Evolution of the microstructure of cobalt during diffusionless transformation cycles
Differential scanning calorimetry and transmission electron microscopy have been used to study thermal fatigue due to diffusionless phase transformation cycling in pure cobalt. Thermal cycling through the allotropic (hcp ↔ fcc) transformation results in a temperature shift of the calorimetric peaks, which means a delay of the transformation. In addition, the transformation enthalpy, which is greater on heating than on cooling, diminishes when the number of transformation cycles increases. This is interpreted as being due to an evolution of the microstructure. Transmission electron microscopy shows the appearance of transformation-induced defects, which are mainly sessile dislocations. We can interpret the calorimetry results (enthalpy evolution and transformation delay) as due to the interactions between interface dislocations and these sessile dislocation
V ie liturgique et quotidienne a Carthage vers le milieu du lIJe siecle. Le témoignage de saint Cyprien et de ses contemporains d'Afrique [Reseña]
Reseña de VICTOR SAXER, "Vie liturgique et quotidienne a Carthage vers le milieu du
lIJe siecle. Le témoignage de saint Cyprien
et de ses contemporains d'Afrique",
1 vol. de 454 págs., Studi di antichita
cristiana pubblicati a cura del Pontificio Istituto di Archeologia Cristiana, XXIX, Citta del Vaticano, 1969
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