Profile analysis of powder diffraction lines was performed to determine the change of lattice parameters versus temperature in order to establish the crystal symmetry of each structural phase and to measure the temperatures of the transitions. From the splitting of the 400 cubic Bragg line and consideration of Glazer's classification of tilted octahedra in perovskites, the various types of distortions were found. Sequences of CaF6 tilting octahedra occurring during the phase transitions are suggested and discussed for each concentration.

The recrystallization of amorphous GaF3 leads to well-crystallized rhombohedral GaF3 (Rh-GaF3). We have determined the fine structure parameters of Fe3+ in Rh-GaF3 from crystalline powder EPR spectrum simulation. We have then studied the evolution of the fine structure parameters along the recrystallization process. Fine structure parameters of GaF3:Cr3+, AlF3, and InF3 crystalline powders (doped with CrF3 and FeF3) were also determined. The superposition model allowed us to compare lattice relaxation around Cr3+ and Fe3+ probes in these compounds. It shows that Cr3+ and Fe3+ ions are well adapted for the EPR studies of Ga3+-containing compounds. Amorphous PbGaF5 recrystallization leads to PbGaF5 powder, whose crystallinity, from a local point of view, is not as good as that obtained by direct solid state synthesis. PZG glass recrystallization leads to a mixture of compounds. EPR spectra changes versus heating time treatment are described and interpreted. (C) 1996 Academic Press, Inc.

In France, cases of cercarial dermatitis were reported in June and July 1994 to the health authorities of three departements in the Pays de la Loire Region (western France). The epidemiological situation, common to the three maintained ponds that were concerned, is as follows: high level of eutrophication of the sites, colonization of the ponds by L. ovata, and settlement by many duck colonies. The simultaneous occurrence of these three phenomena, combined with long hours of sunshine in the summer, is responsible for most of the foci of cercarial dermatitis recently described in Europe.

Control of this condition is difficult, requiring strict maintenance of bodies of water and if necessary the use of molluscicides such as niclosamide. The use of praziquantel in baits for treating the definitive hosts appears to interrupt the natural cycle of the avian Schistosomatidae.

In the light of the observations reported here and the analysis of recent publications, cercarial dermatitis may be regarded as an emerging disease. Its public health impact needs to be evaluated at the global level.

Case report. A case of locally acquired diffuse lepromatous Hansen's disease was observed in a patient who developed acrocyanosis with distal necrosis over a period of several years. Late cutaneomucal signs led to the diagnosis of Hansen's disease after eliminating sarcoidosis and tuberculosis. Skin biopsy with Ziehl stain confirmed the lepromatous nature of the disease. In addition the patient had undergone splenectomy following trauma and also developed babesiasis (a rare protozoan disease in Europe-15 cases reported-similar to Texas fever).

Discussion. The source of infection in this case of Hansen's disease was not found. As in the other cases reported in the literature, late diagnosis due to lack of any suggestive context allowed the disease to develop into an advanced stage.

In a mono-logistic process, the phenomenon is adequately described by only one logistic function. The growth kinetics is then characterized by the properties of each of phases G(1) to G(4), with boundaries defined by the singular points Gamma(max), V-max and Gamma(min) (Buis, 1991, 1993). The growth structure (temporal or diachronic structure) is defined by the relative contribution of the various phases to the expression of the total growth (duration, growth amount, in relative values per phase, independently of y(max)). This temporal distribution of the growth activity is a discretized representation of the trajectory y(0) --> y(max).

A multi-logistic process corresponds to any growth kinetics which is the sum of 2 or several generalized logistics. The number of singular points (local extrema of V and Gamma), and therefore the number of phases G, are then higher than in the mono-logistic case. The growth structure defines precisely the kinetics of the phenomenon as well as the relative importance of the various logistic components in the course of time.

The application presented concerns the growth of the pleuridiophoral cells of the alga Antithamnion plumula (Rhodophyceae, Ceramiales). Cells elongation is of the bi-logistic type. The elongation growth structure characteristics afford a clear discrimination between the sporophyte and the male and female gametophytes. Whereas component 1 (which is the more important at the beginning of growth) hardly changes, component 2 varies dramatically with the thallus ploidy. In contrast, there are few differences between the two gametophytes.

The growth structure concept is thus liable to lead to original results. Beyond the example selected, the approach considered is put forward as a simple but precise characterization method for any growth kinetics based on temporal variations of the growth activity [(V, Gamma) couple].

Case report. A 43-year-old man with a past history of alcoholic cirrhosis and ascitis was hospitalized for skin disorders which had developed over the past 4 months. Centrifugal erythematous skin lesions were observed, some with non-turgid bullae and marginal desquamation, others with an erosive center. Lesions first appeared on the hands then diffused widely without involving the periorifical areas, folds and lower limbs. Laboratory results revealed an anemia, hypovitaminosis K, cholestatic liver failure, a beta-gamma block and low zinc levels. Histology study of the skin biopsy demonstrated a << Neapolitan trench >> image suggestive of ENM. A paraneoplasic syndrome and pancreas tumor were not found. Despite supplementation with zinc, amino acids and vitamins, the patient died from his liver disease.

Discussion. There have been 4 cases of ENM reported in the literature, all in cirrhosis patients, two of which had low zinc levels. Our case is thus the third with cirrhosis and low zinc. Bazer's syndrome, acrodermatitis enteropathica, annular chronic lupus erythematosis and annular superficial pemphigus were eliminated as possible diagnoses. The failure of zinc and amino acid supplementation would favor the secondary nature of the zinc deficiency and the predominant role of cirrhosis in this skin disease. The possible role of essential fatty acids in ENM is raised.

The metal position is occupied statistically with copper and ruthenium and is surrounded by a nearly regular octahedron of anions. The square base plane of this octahedron consists of hydroxide-anions, the apical positions are occupied by oxide anions. Each of these octahedron shares two opposite edges of the square base plane with two other octahedrons, so that linear chains are built up. Each octahedron is also connected to two others by sharing the apical corners, so that the chains construct two-dimensional planes, which are not connected to each other, but by possible hydrogen-bonds. Several models of local ordering are discussed.