Stochastic Variational Search for ΛΛ4^{4}_{\Lambda\Lambda}H

A four-body calculation of the $pn\Lambda\Lambda$ bound state, $^{\ 4}_{\Lambda\Lambda}$H, is performed using the stochastic variational method and phenomenological potentials. The$NN$,$\Lambda N$, and$\Lambda\Lambda$potentials are taken from a recent Letter by Filikhin and Gal, PRL{\bf 89}, 172502 (2002). Although their Faddeev-Yakubovsky calculation found no bound-state solution over a wide range of$\Lambda\Lambda$interaction strengths, the present variational calculation gives a bound-state energy, which is clearly lower than the$_\Lambda^3{H}+\Lambda$threshold, even for a weak$\Lambda\Lambda$interaction strength deduced from a recent experimental$B_{\Lambda\Lambda}(^{6}_{\Lambda\Lambda}{He})$value. The binding energies obtained are close to, and slightly larger than, the values obtained from the three-body$d\Lambda\Lambda$ model in the Letter.Comment: Corrected typos, added addtional calculations regarding a truncated to l=0 interaction model, 4 pages, 3 figure

The (K-,p) reaction on nuclei with in-flight kaons

We perform a theoretical study of the spectrum of protons with kinetic energies of around 600 MeV, emitted following the interaction of 1 GeV/c kaons with nuclei. A recent experimental analysis of this (K-,p) reaction on 12C, based on the dominant quasielastic process, has suggested a deeply attractive kaon nucleus potential. Our Monte Carlo simulation considers, in addition, the one-and two-nucleon K- absorption processes producing hyperons that decay into \pi N pairs. We find that this kaon in-flight reaction is not well suited to determine the kaon optical potential due, essentially, to the limited sensitivity of the cross section to its strength, but also to unavoidable uncertainties from the coincidence requirement applied in the experiment. A shallow kaon nucleus optical potential obtained in chiral models is perfectly compatible with the observed spectrum.Comment: To appear in the proceedings of the 10th International Conference on Hypernuclear and Strange Particle Physics, Tokai, Ibaraki (Japan), 14-18 September, 200

Glomerulonefrite pós-infecciosa hipocomplementêmica aguda como complicação de celulite orbitária relacionada aos seios paranasais: relato de caso

Group A beta-hemolytic streptococcus is the most common agent implicated in post-infectious acute glomerulonephritis. We report a case of acute poststreptococcal glomerulonephritis associated with sinus-related orbital abscess in an 11-year-old boy treated with surgical drainage and intravenous ceftriaxone and clindamycin. Twelve days after supportive measures, renal function was normalized. We also discuss this potentially severe nonsuppurative complication of orbital cellulitis caused by group A beta-hemolytic streptococcus.Os estreptococos beta-hemolíticos do grupo A são os agentes mais comumente envolvidos na glomerulonefrite aguda pós-infecciosa. Relatamos um caso de glomerulonefrite pós-estreptocócica aguda associada a um abscesso orbitário secundário à sinusite, em menino de 11 anos de idade, o qual foi tratado com ceftriaxona e clindamicina endovenosas e drenagem cirúrgica. Doze dias após tratamento de suporte, a função renal se normalizou. Também discutimos a importância desta grave e potencial complicação não supurativa das celulites orbitárias causadas pelos estreptococos beta-hemolíticos do grupo A

Upper lid crease approach for margin rotation in trachomatous cicatricial entropion without external sutures

ABSTRACT Purpose: To describe the use of a lid crease incision for upper eyelid margin rotation in cicatricial entropion combining internal traction on the anterior lamella, tarsotomy, and tarsal overlap without external sutures. Methods: Surgical description: The main steps of the procedure consisted of exposure of the entire tarsal plate up to the eyelashes followed by tarsotomy through the conjunctiva. A double-armed 6.0 polyglactin suture was then passed through the distal tarsal fragment to the marginal section of the orbicularis oculi muscle. As the sutures were tied, the distal tarsus advanced over the marginal section, and traction was exerted on the marginal strip of the orbicularis muscle. There were no bolsters or external knots. The pretarsal skin-muscle flap was closed with a 6.0 plain gut suture. Results: We used this procedure at a tertiary hospital in Saudi Arabia from 2013 to 2014. Sixty upper lids of 40 patients (23 women and 17 men) were operated on, with an age range of 44-99 years [mean ± standard deviation (SD) = 70.9 ± 13.01 years]. Bilateral surgery was performed on 21 patients. Follow-up ranged from 1 to 12 months (mean 3.0 ± 2.71 months). Forty percent of the patients (24 lids) had more than 3 months' follow-up. The postoperative lid margin position was good in all cases. Trichiasis (two lashes) was observed in only one patient with unilateral entropion on the medial aspect of the operated lid. Conclusions: The upper lid margin can be effectively rotated through a lid crease incision with internal sutures. The technique combines the main mechanisms of the Wies and Trabut approaches and avoids the use of bolsters or external sutures, which require a second consultation to be removed. Some other lid problems, such as ptosis, retraction, or dermatochalasis, can be concomitantly addressed during the procedure

Kˉ\bar K nuclear bound states in a dynamical model

A comprehensive data base of K- atom level shifts and widths is re-analyzed in order to study the density dependence of the Kbar-nuclear optical potential. Significant departure from a t*rho form is found only for nuclear densities about and less than 20% of nuclear-matter density, and extrapolation to nuclear-matter density yields an attractive potential, about 170 MeV deep. Partial restoration of chiral symmetry compatible with pionic atoms and low-energy pion-nuclear data plays no role at the relevant low-density regime, but this effect is not ruled out at high densities. Kbar-nuclear bound states are generated across the periodic table self consistently, using a relativistic mean-field model Lagrangian which couples the Kbar to the scalar and vector meson fields mediating the nuclear interactions. The reduced phase space available for Kbar absorption from these bound states is taken into account by adding an energy-dependent imaginary term which underlies the corresponding Kbar-nuclear level widths, with a strength required by fits to the atomic data. Substantial polarization of the core nucleus is found for light nuclei, and the binding energies and widths calculated in this dynamical model differ appreciably from those calculated for a static nucleus. A wide range of binding energies is spanned by varying the Kbar couplings to the meson fields. Our calculations provide a lower limit of Gamma(Kbar) = 50 +/- 10 MeV on the width of nuclear bound states for Kbar binding energy in the range B(Kbar) = 100 - 200 MeV. Comments are made on the interpretation of the FINUDA experiment at DAFNE, Frascati, which claimed evidence for deeply bound (K- pp) states in light nuclei.Comment: Added 2 figures and discussion. Version accepted for publication in NP

Abscesso orbitário secundário à dacriocistite aguda: relato de caso

Acute dacryocystitis usually induces preseptal infection. In rare instances the infection that is confined to the lacrimal sac can extend to the orbital contents resulting in orbital cellulitis. We present a case of intraconal abscess secondary to acute dacryocystitis and review the literature of orbital cellulitis resulting from acute lacrimal sac infection.A dacriocistite aguda comumente evolui para infecção pré-septal. Raramente a infecção localizada no saco lacrimal pode estender-se ao conteúdo orbitário resultando em celulite orbitária. Apresentamos um caso de abscesso orbitário intraconal secundário à dacriocistite aguda e uma revisão de literatura de celulite orbitária causada por infecção aguda do saco lacrimal

A search for deeply bound kaonic nuclear states

We have measured proton and neutron energy spectra by stopping negative kaons on liquid helium4. Two distinct peak structures were found on both spectra, which were assigned to the formation of new kinds of strange stribaryons. In this paper, we summarize both results.Comment: 7 pages, 3 figures, HYP2003 conference proceeding

Latest results for the antikaon-nucleon optical potential

The key question of this letter is whether the K-nucleus optical potential is deep, as it is prefered by the phenomenological fits to kaonic atoms data, or shallow, as it comes out from unitary chiral model calculations. The current experimental situation is reviewed.Comment: 3 pages, 1 figure. Presented at the 21st European Conference on the Few-Body problems in Physics (EFB21), Salamanca, Spain, August 29 - September 3, 201

Recent developments in chiral dynamics of hadrons and hadrons in a nuclear medium

In this talk I present recent developments in chiral dynamics of hadrons and hadrons in a medium addressing the following points: interaction of the octet of pseudoscalar mesons with the octet of baryons of the nucleon, showing recent experimental evidence on the existence of two $\Lambda(1405)$ states, the interaction of the octet of pseudoscalar mesons with the decuplet of baryons of the $\Delta$, with particular emphasis on the $\Lambda(1520)$ resonance, dynamically generated by this interaction. Then I review the interaction of kaons in a nuclear medium and briefly discuss the situation around the claims of deeply bound states in nuclei. The large renormalization of the $\Lambda(1520)$ in the nuclear medium is shown as another example of successful application of the chiral unitary techniques.Comment: Talk at the Fifth International Conference on Perspectives in Hadronic Physics: Particle-Nucleus and Nucleus-Nucleus Scattering at Relativistic Energies, Trieste, May 200

Chirally motivated K^- nuclear potentials

In-medium subthreshold KbarN scattering amplitudes calculated within a chirally motivated meson-baryon coupled-channel model are used self consistently to confront K^- atom data across the periodic table. Substantially deeper K^- nuclear potentials are obtained compared to the shallow potentials derived in some approaches from threshold amplitudes, with Re V_{chiral} = -(85+/-5) MeV at nuclear matter density. When KbarNN contributions are incorporated phenomenologically, a very deep K^- nuclear potential results, Re V_{chiral+phen.} = -(180+/-5) MeV, in agreement with density dependent potentials obtained in purely phenomenological fits to the data. Self consistent dynamical calculations of K^- nuclear quasibound states are reported and discussed.Comment: extended discussion, unchanged results and conclusions, accepted by PL