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The sheet conductance of gold condensates on MgO and a-C is expressed in terms of granulometric quantities. This expression enables us to follow the evolution of metal repartition on its substrate during the gold evaporation. The difference between the growth modes of these gold layers on MgO and on a-Cis explained by the predominance of respectively nucleation and coalescence phenomena

Resume On a observe, lors de la croissance d'un depot sur un support metallique, deux sortes de dislocations interfaciales. Les premieres sont caracterisees par un vecteur de Burgers parallele a l'interface. On les interprete comme etant associees a une deformation elastique et homogene du depot, liee elle-meme a l'adaptation des parametres differents du support et du depot. Les deuxiemes apparaissent sous la forme de lignes droites. Elles ont un vecteur de Burgers incline par rapport a l'interface. On les interprete comme resultant d'un processus de glissement de dislocations existant dans le support, a la suite de contraintes epitaxiques dependant des proprietes elastiques du dit support et du depot.

Resume Des couples minces obtenus par epitaxie sont etudies par microscopie et diffraction electronique dans le but de determiner le type de defauts introduits a l'interface au cours de la croissance du depot. Differents couples ont ete consideres: Pd/Au(111), Pd/Au(001), Au/Pd(001) et Ni/Au(111); les depots ont des epaisseurs variables et inferieures a 10 nm. Deux types de dislocations sont ainsi observes: dans le cas des couples Pd/Au(111), Pd/Au(001) et Au/Pd(001) et pour des epaisseurs des depots voisines de 1 nm, apparaissent de courtes lignes de dislocations dont la densite augmente rapidement avec l'epaisseur deposee et ces dislocations forment alors un reseau assez regulier dans l'interface; elles sont purement coin et ont un vecteur de Burgers b = ( a 2 )〈110〉FX parallele a l'interface. Un second type de dislocations apparait dans le cas des couples Pd/Au(111), Pd/Au(001) et Ni/Au(111); elles se presentent sous forme de lignes droites localisees dans le support et caracterisees par leur nature mixte et leur vecteur de Burgers incline par rapport au plan de l'interface considere.

Resume Des particules de nickel preparees par reduction d'un halogenure de nickel en milieu organique liquide ont ete etudiees en microscopie et diffraction electroniques. Elles ont une dimension moyenne de 30 nm et des formes variees; 8% d'entre elles ont une forme icosaedrique. Des diagrammes de diffraction ont ete obtenus sur des particules icosaedriques isolees traversees par le faisceau suivant un axe de symetrie Λ 2 . L'interpretation de ces diagrammes, en utilisant differents modeles de structures, indique que ces particules sont constituees par vingt tetraedres de structure c.f.c. regulierement repartis autour d'un sommet commun.

Conditions for the maintenance of males in androdioecious populations (populations with both male and hermaphrodite individuals) have been derived for four different one-locus two-allele models of inheritance of androdioecy. The results are not in general accordance with those already known: depending on the mode of inheritance, males can be maintained irrespective of their fertilities. If males are sufficiently fertile, it may happen that they are maintained only for intermediate selfing rates of the hermaphrodites. A result already found for gynodioecy is confirmed for androdioecy, namely, that a 1∶1 sex ratio is immediately established among zygotes if hermaphrodites appear as heterozygotes only.

Motivated by problems frequently occurring in the analysis of evolutionary ecological and population genetic models, discrete dynamical systems on the product of compact topological spaces are considered which contain an independent subsystem on one component space. If this subsystem possesses an equilibrium point, then a dynamical system is defined on the other component space whenever the independent system is in equilibrium. It is shown that in the presence of global asymptotic stability in the two component systems, perturbation will result in a return of the entire system to equilibrium (i.e. in particular, the equilibrium is globally asymptotically stable). A weakening of these conditions to combinations of global attractivity and global asymptotic stability either no longer guarantees convergence, or else the equilibrium is globally attractive but unstable, and thus sensitive to further perturbation.

Nickel films are deposited on thick copper substrate by electron beam evaporation, sputtering and electrodeposition. The film structure is characterized by Transmission Electron Microscopy. The diffusion of Cu through Ni films is investigated by Auger electron spectroscopy using the method of “the first arrival”. The diffusion anneals are performed between 300 and 450°C. It appears that grain boundary diffusion occurs in these bimetallic couples. Diffusion coefficients are determined (for vacuum deposited films D 0 =4.9×10 -5 cm 2 s -1 , Q =25.7 kcal mol -1 and for electroplated films D 0 =2.4×10 -9 cm 2 s -1 , Q =17.4 kcal mol -1 . Electroplated Ni films show more effective barrier diffusion for Cu than in the case of vacuum deposited films. This is mainly due to larger grain size.

The CO adsorption and CO and O 2 coadsorption on Pd(111) under catalytic conditions (i.e. during exposition to CO and O 2 mixture at various surface temperatures) has been studied using the technique of static secondary ion mass spectroscopy (SSIMS). It is shown that the SSIMS method gives information about the oxygen coverage and the formation of COO coadsorbed phase during catalysis.

An approximation, derived from the self-consistent-field-molecular-orbital method, which includes nuclear repulsion is proposed to study metallic structures of alkali atoms. The method allows the evaluation of the average energy per atom in the massive crystal and the loss of stability in various smaller samples according to their crystal lattice. The method was applied to lithium. Several atomic lattices, bcc, fcc, and pentagonal symmetry, were studied as a function of the number of atoms. The distance between nearest neighbors deduced from bond orders is identical for pentagonal and for fcc structures and bigger than the one for the bcc system. Surface energies were evaluated using the destabilization terms relative to the surface atoms. The relative stability of the crystalline lattices was investigated as a function of the number of atoms and of the spatial conformation of the structures. It appears that small-sized structures have an atomic lattice different from that of massive crystals. Thus, the bcc system becomes prefered only for structures having more than about ${10}^{6}$ atoms.

A method of preparation of gold particles by evaporation technique in a flowing argon system is presented. Density, size distribution and size dispersion of particles for various atom gold fluxes, argon volume flows and specimen position in the collection chamber were studied. The results showed that if the gold flux was sufficiently high, the argon nucleated particle density could be compared with the heterogeneous nucleated one. An homogeneity in particle size with a low dispersion was obtained (30 A) for a mean size in a range 60–200 A.

The formation and growth of small metal particles (40–250 A) produced by gas evaporation in a flowing argon system have been studied. With investigation of nucleation rate in the gas it is shown that particles grow without coalescence phenomena. Morphology and structure of Au, Pt and Pd particles have been investigated by electron diffraction and microscopy, so as to determine the substrate dependence on the formation of aggregates with fivefold symmetry axes (decahedral and icosahedral structure). As gold particles condense onto a substrate, microscopy shows that icosahedral and decahedral particle growth in argon is favoured with respect to fcc ones, whereas in the case of Pt and Pd particles these anomalous structures are less numerous than ones condensed onto a substrate.

Using a “layer by layer” mechanism for the growth process of small gold particles growing on alkali halide substrates, we consider that initial growth starts with a bidimensional nucleation on particle faces. It is shown that one bidimensional nucleus on a face of an icosahedral particle gives rise to a complete layer on all the faces, when the nucleation of one bidimensional nucleus on the face of an fcc particle generates a layer on only one face. The growth kinetics of icosahedral and fcc particles are compared and it is concluded that in the early state icosahedral particles growth is the fastest.

The study was carried out on patients with intermittent claudication (Fon taine's stage II). The arterial and atheromatous origin of the disease was con firmed and localized by angiography or Doppler velocimetry examination. One hundred eighty-six patients were selected initially. Their pain-free walk ing distance on a treadmill (at a speed of 3 km/hour and an inclination of 10%) had to be 150-300 m. During the first month all patients received 3 placebo tablets daily. At the end of this run-in period (D-30; D 0) and after checking walking distance stability (allowed variation: ±20% between the two measurements) the patients were included in the study. One hundred fifty-four patients were se lected and 118 remained during the whole study. The study was designed as a double-blind, using two parallel randomly selected groups. Sixty-four patients received for six months Naftidrofuryl (3 × 200 mg tablets daily with meals); 54 patients received placebo under the same conditions. Dur ing this period, clinical and paraclinical examinations were carried out every quarter (D 90 and D 180). After checking the initial homogeneity of the Naftidrofuryl and placebo- groups, the comparison between groups indicates a significant improvement in Naftidrofuryl group after 3 and 6 months of treatment. At the end of the study the observed differences in walking distance with Naftidrofuryl are approxi mately twice the difference in the reference group (D 90: p < 0.05; D 180: p < 0.02). The results of this study indicate that Naftidrofuryl is an efficient pharmacological tool for treatment of patients with chronic arterial disease (Fontaine's stage II).

Resume Une etude en microscopie et diffraction electroniques a ete realisee sur des particules de nickel obtenu par reduction en phase liquide d'un sel de nickel. Elles ont des formes diverses dont la dimension moyenne est 300 A. Les resultats presentes dans cette publication portent sur la structure et la morphologie de particules de forme hexagonale allongee et de section pentagonale. Par l'observation des contrastes en fond clair et en fond noir et des figures de diffraction suivant differentes orientations par rapport au faisceau on montre que ces particules admettent comme modele une forme decaedrique avec une forte anisotropie de croissance suivant l'axe Λ5.

Etude par spectrometrie Auger, diffraction d'electrons et microscopie electronique en transmission de la formation de l'interface Pd/Al 2 O 3 . Etude des differentes etapes de la croissance d'un film de palladium condense sous ultra-vide sur un monocristal d'alumine α caracterise chimiquement et cristallographiquement. Les differents stades de croissance sont l'adsorption d'atomes isoles, la diffusion dans le substrat, la germination et croissance de cristallites tridimensionnels. Determination des relations epitaxiques depot-support

Resume La croissance de l'argent sur le palladium est suivie en continu par spectrometrie Auger. Selon la temperature du support de palladium on met en evidence deux types de croissance: -a temperature “moderee” (20–200 °C) croissance couche par couche (Franck-van der Merwe) sans interdiffusion; -a temperature “elevee” (250–350 °C) formation d'un alliage en surface. Les couches Ag-Pd formees sont analysees par spectrometrie Auger au cours d'un decapage ionique suivi en continu.

The morphology and crystallographic structure of small palladium particles prepared by condensation onto NaCl(001) and mica substrates were investigated using electron diffraction and high resolution defocused dark field and strong beam and weak beam dark field transmission electron microscopy imaging techniques. Sample tilting through large angles was used to characterize particles with a rhombic outline and with irregular outlines. Thus, under conditions with very low deposition rates, it is possible to obtain decahedral or icosahedral particles of which a very high proportion have f.c.c. structure. These results are the opposite of previous ones. On NaCl(001) substrates, the proportion of decahedral particles is about 90% and the size can reach 2000 A. On mica substrates, the proportion of icosahedral particles 150 A in size is about 95%.

Resume La structure de tres petits agregats d'or condenses sur un clivage de NaCl a ete examinee par diffraction et microscopie electroniques; on a montre qu'au-dela d'une certaine taille (environ 80 A) les agregats icosaedriques presentent un defaut de fermeture qui montre une transition entre la structure icosaedrique et la structure c.f.c. multimaclee.

Resume La structure de petits agregats de platine obtenus par condensation sous vide sur les supports de NaCl (001), NaCl(111) et mica a ete etudiee par microscopie et diffraction electroniques. Les observations montrent qu'a partir d'une certaine temperature du support il existe des particules de structure decaedrique ou icosaedrique. Ces particules sont pratiquement absentes sur des substrats clives sous ultravide. Elles sont toujours en proportion beaucoup plus faible que dans le cas des films minces d'or prepares dans les memes conditions. Pour tenter d'expliquer ce fait trois hypotheses sont emises: (1) la formation initiale des germes de structure anormale est contrariee par le support; (2) les particules sont detruites avant d'atteindre la taille correspondant a nos observations; et (3) les particules resultent d'un mecanisme de coalescence donnant des agregats multimacles.

An allele or genotype is called protected if for all initial genotype frequencies positive it cannot be lost or does not remain at very low frequencies indefinitely. An analysis of protectedness was made for gynodioecious populations (populations with both female and hermaphrodite individuals) with four different types of one-locus two-allele models for the inheritance of gynodioecy. Ovule and pollen fertilities, together with selfing rates may differ between hermaphrodite genotypes. Such factors have not been considered previously, and lead to new conditions for the maintenance of the sex polymorphism. In particular, the mode of genetic control, and the hermaphrodite ovule and pollen fertilities, together with their selfing rates, may determine whether the female genotype is protected. Differential selfing among hermaphrodites may lead to overdominance and allow the maintenance of the polymorphism, and such differential selfing probably occurs in natural gynodioecious populations. In this connection the significance of models of inbreeding depression was considered.

Resume Des tetraedres de defauts d'empilement resultant de l'elimination des lacunes introduites par trempe peuvent etre observes par microscopie electronique, dans de l'or spectrographiquement pur et dans de l'or de purete commerciale a condition que celui-ci soit trempe tres rapidement. Une explication qualitative de ce phenomene peut etre donnee en fonction de la purete des echantillons et de la vitesse de trempe realisee.

Iron is evaporated on a (111) gold face. Growth up to 25 A thickness shows three-dimensional crystallites in epitaxy: (110) Fe//(111) Au. The length ([001] orientation) and the number of these crystallites increase with increasing thickness but the width ([110] orientation) is constant (75 ±15 A). To explain these results the interface equilibrium is calculated by means of Van der Merwe's interfacial dislocations. The first monolayer should grow with the same parameters that the gold substrate while interfacial dislocations are generated starting from the second layer. Yet the deposit is stable only within the distance of two neighbouring dislocations then determining a theoritical width limit of 60 A.

The study of nuclei of gold deposited on alkali halides cleaved in ultra high vacuum shows that the early deposits are multiple particles. The mainly multiple particules have pentagonal or hexagonal contours and consist of five or twenty crystals in twin position. It has been suggested that these particles result from a successive twin formation process based on tetrahedron nucleus. However the particles observed in high resolution electron microscopy (making possible the direct imaging of lattices) did not exhibit defects due to this growth process. An alternative formation mecanism is proposed: the growth is performed by adding atom by atom to a nucleus consisting of seven atoms (pentagonal particles) or twelve atoms (hexagonal particles) packed as closely as possible like pseudo-nuclei which are found in liquids. The pentagonal particles nuclei exhibit fivefold symmetry and further growth layer by layer in a fcc structure slightly distorted (5 0 0 ) keeps the initial symmetry and form. The hexagonal particles nuclei have also fivehold symmetry axes which are growth-axes. The structure of the multiple particles grown in this manner is in good agreement with the electron patterns and micrographs obtained.

Iron was deposited in ultrahigh vacuum onto thin single-crystal films of gold oriented with (111) parallel to the surface plane. Study by electron diffraction and electron microscopy has shown that the initial growth of iron occurs by successive monolayers. Three stages in the deposit growth have been found: first the deposited film of iron is strained to match the gold substrate exactly; then interfacial dislocations appear at the gold-iron interface; and finally iron nuclei of b.c.c. structure are formed. The interfacial dislocations are in mixed orientation with their Burgers vectors 12a 〈110〉 inclined to the gold-iron interface; it is found that they have a poor efficiency for accommodating the misfit between the substrate and the deposit, so that for deposits of average thickness greater than 8 A the interface is mostly incoherent.

A Brillouin investigation has been performed in (NH 4 ) 2 ZnCl 4 above room temperature. The investigated temperature range encloses the transition near 46°C andthe incomensurate phase between 91 and 133°C. Small anomalies of elastic constants appear at the transitions. They are qualitatively discussed.]

In this paper, we show that it is possible to deduce the actual morphology of small particle condensed onto an insulator by combining the granularity analysis from electron micrographs and the electrical sheet conductance of the deposit on its substrate. Assuming the particles are truncated ellipsoids, we determine the excentricity and the contact angle with the substrate for Au on amorphous carbon and MgO substrates.

A post-operative use of the calorico-nitrogenous mixture: Trivé 1000 was carried out in 25 patients after digestive surgery. The prescribed dose of this lipidic emulsion was 1,36 1 for an average period of four days. A study of the results led to establish the following facts:--a 55 p. cent increase in the nitrogen retention in comparison with a control series of ten patients and from (J o) the day of the intervention to (J F) the day when the treatment was stopped. Besides, the duration of the treatment did not seem to modify this balance, at least within the limits of the period of use. On the other hand, the quantity of EB 51 was a determining factor since 2000 ml were necessary to obtain a positive nitrogen balance (+ 0.96 g).--a very small rise in the amino-acid serous rate. It appeared in 14 patients and, supplied by EB 51, 3 other amino-acids increased their proportion spontaneously (Asp.--Gluc.--Tau.).--a reduction of the rate of 5 amino-acids, one of which, however, (Arginine) was being supplied by the drip. The variations were never statistically significant but for the Phenylalanine rate increase.--a non-systematic variation in the blood proteids that decreased as far as total proteids and albumin were concerned and that increased as far as globulins alpha1 and alpha2 were concerned.--Finally, no variations in the serous graphic record of lipid levels were noted, neither in the average of figures, nor in the analyses carried out after each bottle. Besides, it must be added that the tolerance of the product was excellent both on a general level (very few cases of intolerance: 4) and on the level of the plasma turbidimetry which did not reveal and chylomicrons except in one case. Therefore Trivé 1000 proved to be an interesting nutrient combinatin quite suited to a parenteral feeding because of its high caloric power. The necessity of a calories/g/nitrogen ratio from 100 to 200 corresponding to 2000 ml of EB 51 was once more evidenced. Therefore such a dose (for lack of a protein assimilation) allows for a nitrogen retention important enough to prevent an excessive consumption of the body proteinic reserves. Such doses are perfectly tolerated both on the general and metabolic levels (mainly on the lipometabolic one).

In animal models, the development of Echinococcus multilocularis larvae has been shown to correlate with the immune status of the host, and particularly with cellular immunity. In humans, a defect in immune regulation may explain the persistence of cellular infiltration and fibrogenesis. We assessed natural killer (NK) activity in the peripheral blood mononuclear cells (PBMC) of patients with alveolar echinococcosis, and compared in 12 patients who underwent a surgical procedure the cell populations in the PBMC with those present in the periparasitic granuloma. The results indicated that (i) the NK cell activity of the PBMC was significantly altered at the lower NK cell: target cell ratios; (ii) the percentage of CD8+ cells was significantly decreased in the PBMC with an increased CD4:CD8 cell ratio; (iii) inversely, the CD8+ cells constituted the main population of T cells in the liver of most patients; and (iv) the periparasitic granuloma was mainly composed of macrophages, T cells and myofibroblasts in close association with the developing fibrosis. A relatively high number of CD4+ cells in the periparasitic granuloma of two patients with 'abortive' parasitic lesions suggested that, as it is observed in experimental E. multilocularis infection, differential evolution of the phenotypic pattern of the periparasitic granuloma could be related to resistance or sensitivity to infection by E. multilocularis in humans.

Lipase and phospholipase A activities were increased in the pancreas and pancreatic juice of rats ingesting during two months 20% phospholipids- or triglycerides-rich diets. The activity of lipase is higher with the triglycerides-rich diet and the phospholipase A activity is higher with the phospholipids-rich diet. After seven days of the experiment, these two enzymes activities were less increased with diet containing 40% lipids.

A triple human catheter was used for the determination of cardiac output during the acute phase of moycardial infarction in 23 patients. The correlation coefficient between thermodilution and the Fick method was 0.91. Precision of the method assessed by multiple repeated determinations was 4.8 or 5.6%. Quadruplicate determinations allowed to detect variations of cardiac output in the range of 0.465 1/min. Variation between two successive determinations of more than 9.4% can probably be attributed to a technical error.

Intravenous mexiletine (250 mg in 10 min) given to patients at the acute stage of a myocardial infarction was responsible of a mild decrease of the left ventricular function; two of our patients presented bradycardia with hypotension, immediately corrected by atropine (i.v.). Adverse hemodynamic effects are seldom reported after oral administration.

The authors report a case of hypernephroma revealed by an acute surgical abdomen. The laparotomy found a stercoral peritonitis. A review of the literature shows that this observation is exceptional.

The authors report a case in which hyperparathyroidism recurred after total parathyroidectomy and autogenous parathyroid graft into the fore-arm musculature, in a patient with chronic renal failure. Light and electron microscopic studies of the grafted tissue show a severe, nodular hyperplasia. This case report illustrates the rapid "tumour-like" growth of the hyperplastic parathyroid grafted tissue; according to some authors, the hyperplastic parathyroid tissue displays an increased propensity to become malignant.

Among congenital dilatations of the common bile duct, a congenital diverticulum of the common bile duct may remain clinically latent for a long period. One case is reported in a 77 year old subject. Precise diagnosis of the disease is often made at operation and on pathological examination. The diverticulum is cured in most cases after surgery which consists of simple removal, but which may sometimes require reconstruction of the common bile duct.