- Charged-particle exclusive analysis of central Ar + KCl and Ar + Pb reactions at 1.8 and 0.8 GeV/nucleon (1983)
- An event by event analysis is carried out for all charged particles observed in central collisions of 40Ar + KCl and 40Ar + Pb at 1.808 and 0.772 GeV/nucleon, respectively. Total transverse energy is used for impact parameter selection within the central trigger condition. The central Ar + KCl reaction exhibits a forward-backward oriented momentum flux. The flux distribution of the most central Ar + Pb events is approximately isotropic in the fireball center of mass.
- Human monoclonal antibody combination against SARS coronavirus : synergy and coverage of escape mutants (2006)
- Background: Experimental animal data show that protection against severe acute respiratory syndrome coronavirus (SARS-CoV) infection with human monoclonal antibodies (mAbs) is feasible. For an effective immune prophylaxis in humans, broad coverage of different strains of SARS-CoV and control of potential neutralization escape variants will be required. Combinations of virus-neutralizing, noncompeting mAbs may have these properties. Methods and Findings: Human mAb CR3014 has been shown to completely prevent lung pathology and abolish pharyngeal shedding of SARS-CoV in infected ferrets. We generated in vitro SARS-CoV variants escaping neutralization by CR3014, which all had a single P462L mutation in the glycoprotein spike (S) of the escape virus. In vitro experiments confirmed that binding of CR3014 to a recombinant S fragment (amino acid residues 318–510) harboring this mutation was abolished. We therefore screened an antibody-phage library derived from blood of a convalescent SARS patient for antibodies complementary to CR3014. A novel mAb, CR3022, was identified that neutralized CR3014 escape viruses, did not compete with CR3014 for binding to recombinant S1 fragments, and bound to S1 fragments derived from the civet cat SARS-CoV-like strain SZ3. No escape variants could be generated with CR3022. The mixture of both mAbs showed neutralization of SARS-CoV in a synergistic fashion by recognizing different epitopes on the receptor-binding domain. Dose reduction indices of 4.5 and 20.5 were observed for CR3014 and CR3022, respectively, at 100% neutralization. Because enhancement of SARS-CoV infection by subneutralizing antibody concentrations is of concern, we show here that anti-SARS-CoV antibodies do not convert the abortive infection of primary human macrophages by SARS-CoV into a productive one. Conclusions: The combination of two noncompeting human mAbs CR3014 and CR3022 potentially controls immune escape and extends the breadth of protection. At the same time, synergy between CR3014 and CR3022 may allow for a lower total antibody dose to be administered for passive immune prophylaxis of SARS-CoV infection.
- L’institution de la littérature gabonaise : Partie II (2005)
- Dans le cadre du Séminaire portant « sur la littérature et la société au Gabon », dirigé par monsieur SIMA EYI Hervais-Eméry, enseignant, Directeur-fondateur du Centre d’Etude en Littérature Gabonaise (CELIG), il a été demandé aux étudiants de faire des recherches et voir quelle place les institutions littéraires du Gabon accordait à la littérature gabonaise. Pour notre groupe, il s’est agit de se rendre dans les institutions telles que le Bureau Régional de l’Agence de la francophonie de l’Afrique Centrale (BRAC), Ministère de la culture, des arts et de l’éducation populaire, La Fondation Raponda WALKER, Le Centre Culturel Français ST- Exupéry de Libreville (CCF), La faculté des lettres et sciences humaines de l’Université Omar Bongo et L’Institut Pédagogique National (IPN). Notre objectif consistait à voir quel traitement ces institutions faisaient de la littérature gabonaise et comment elles s’y prenaient pour faciliter sa vulgarisation et sa promotion. Aussi , s’agissait-il d’étudier la nature des rapports ou des relations qui existent entre ces institutions et les écrivains gabonais, quelle place accordaient-elles à la littérature gabonaise et à ses écrivains, et comment procédaient -elles pour promouvoir cette littérature. -------------------------------------------------------------------------------------------- CRELAF (Cercle de Reflexion des Etudiants en Littératures Africaines), Département de Littératures Africaines, Université Omar Bongo, Gabon
- Energy and centrality dependence of deuteron and proton production in Pb+Pb collisions at relativistic energies (2004)
- The transverse mass mt distributions for deuterons and protons are measured in Pb+Pb reactions near midrapidity and in the range 0<mt–m<1.0 (1.5) GeV/c2 for minimum bias collisions at 158A GeV and for central collisions at 40 and 80 A GeV beam energies. The rapidity density dn/dy, inverse slope parameter T and mean transverse mass <mt> derived from mt distributions as well as the coalescence parameter B2 are studied as a function of the incident energy and the collision centrality. The deuteron mt spectra are significantly harder than those of protons, especially in central collisions. The coalescence factor B2 shows three systematic trends. First, it decreases strongly with increasing centrality reflecting an enlargement of the deuteron coalescence volume in central Pb+Pb collisions. Second, it increases with mt. Finally, B2 shows an increase with decreasing incident beam energy even within the SPS energy range. The results are discussed and compared to the predictions of models that include the collective expansion of the source created in Pb+Pb collisions.
- A study of Lambda-production in central nucleus-nucleus interactions at a momentum of 4.5 GeV/c per incident nucleon (1983)
- Analysis of Lambda and associative pion production in relativistic nucleus-nucleus collisions (1984)
- Experimental data on pi-mesons produced in inelastic and central nucleus-nucleus interactions at 4.5-Gev/C momentum per nucleon (1984)
- Eksperimental'nye dannye po srednemu cislu provzaimodejstvovavšich protonov v neuprugich i zentral'nych jadro-jadernych vzaimodejstvijach pri energij 3.6 GeV/nuklon (1986)
- Evidence for an exotic S=-2, Q=-2 baryon resonance in proton-proton collisions at the CERN SPS (2004)
- Results of resonance searches in the Xi - pi -, Xi - pi +, Xi -bar+ pi -, and Xi -bar+ pi + invariant mass spectra in proton-proton collisions at sqrt[s]=17.2 GeV are presented. Evidence is shown for the existence of a narrow Xi - pi - baryon resonance with mass of 1.862±0.002 GeV/c2 and width below the detector resolution of about 0.018 GeV/c2. The significance is estimated to be above 4.2 sigma . This state is a candidate for the hypothetical exotic Xi --3/2 baryon with S=-2, I=3 / 2, and a quark content of (dsdsu-bar). At the same mass, a peak is observed in the Xi - pi + spectrum which is a candidate for the Xi 03/2 member of this isospin quartet with a quark content of (dsusd-bar). The corresponding antibaryon spectra also show enhancements at the same invariant mass.
- GEANT4 : a simulation toolkit (2003)
- Abstract Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics. PACS: 07.05.Tp; 13; 23