Induction Of An Antibacterial Activity In The Hemolymph Of The Manila Clam, Ruditapes philippinarum

Bassem Allam and Michel Auffret

In common with many invertebrates, host defense in bivalves is based largely on non-specific defense activities of circulating hemocytes and humoral factors present in the plasma. The understanding of these defense factors might allow us to manipulate the resistance or tolerance of bivalves to diseases. The present work focused on the effect of the challenge with a pathogen (the bacterium Vibrio tapetis) on antibacterial defense parameters in the hemolymph of its host (the clam Ruditapes philippinarum). Results indicate significant increase in total hemocyte counts and the induction of an antibacterial activity in the hemolymph of challenged animals. These results were discussed with emphasis on the presence in bivalve molluscs of antibacterial peptides close to those found in arthropods. Back

Excited States of ¹⁶⁶Er

E.Eid and N.M.Stewart

The low lying states of ¹⁶⁶Er are interpreted in terms of the rotational-vibrational energy as a function of I(I+1), and the Interacting Boson Model close to the SU(3) limit. The decay scheme of ¹⁶⁶Er is established on the basis of  γ-γcoincidence studies using Ge and Ge(Li) detectors to measure the gamma rays resulting from the Β^- decay of ^166mHo (t _1/2 = 1200Y). Four new transitions at 351.21, 476.29, 895.59 and 1303.09 keV were observed. The first two of which are placed in the decay scheme as well as a new energy level at 1567.35 keV. Back

Convergence Presque Partout des Moyennes Vectorielles Multidimensionnelles

Kassem El Berdan et Hassan Zeineddine

Soient X un espace de Banach réflexif, Ω un espace mesure,T₁,...,T_d des opérateurs linéaires (non commutant), contractant dans L^∞(X) et strictement contractant dans L¹(Ω,X)=L¹(X) (i.e. il existe α_j ∈ ]0,1[ telque
||T_jf|| ≤ α_j||f|| pour tout j = 1,...,d et f ∈ L¹(X)).
Nous montrons une inégalité maximale pour les moyennes:

              
ainsi que la convergence presque partout de celles-ci pour tout f ∈ L¹(X) .
Ceux-ci généralise le théorème de Chacon (Chacon 1962) au cas multidimen- sionnel pour cette classe d’opérateurs.
Enfin, nous donnons, deux opérateurs strictement contractant dans L¹(X), contractant dans L^∞(X)et la convergence presque partout des moyennes n’est pas triviale.Back

A New Preconditioned Quasi-Newton Method For Optimization

Issam A.R. Moghrabi

We address in this paper quasi-Newton methods for nonlinear unconstrained optimization, concentrating on the derivation of a new updating formulae to be used in the preconditioning of the search direction in Conjugate Gradient methods. Such formula is used in obtaining at each iteration a ‘better’ set up of the inverse Hessian [or the Hessian itself], than the current estimate, by performing an alternative simple update operation that uses available iteration data, such as gradient points and iterates..Back

Human Leucocyte Antigen (HLA) Class I And II Frequencies In Selected Groups In Lebanon

Alexander M. Abdelnoor, May Abdelnoor, Walid Heneine, Firas Kobeissi, Sulaf Mansur, Rami Malak and Hanadi Sharara

Human Leucocyte Antigen class I (HLA-A and B) profiles were determined in 461 Lebanese subjects. These included 88 Sunnites, 149 Shiites, 50 Druze, 129 Maronites and 45 Greek Orthodox. HLA class II (HLA-DR and DQ) profiles were determined in 250 Lebanese subjects. These included 50 from each of the mentioned religious groups. The Complement Dependent Micocytotoxicity assay was used for these determinations. Frequencies for HLA epitopes in each religious sect were calculated and are presented. Such data may be important for those who are in the transplantation field and those who wish to study HLA-Disease associations.
The HLA epitope frequencies in the different religious groups studied were compared. The degree of similarity in frequencies ranged from 77% to 96%.Back