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Cervicothoracic syringomyelia is a frequent feature in Chiari I malformation. It can be symptomatic or not, and is well demonstrated by magnetic resonance imaging (MRI). Its spontaneous resolution is uncommon. The authors report a case of spontaneous resolution of a thoracic syrinx in an 18-year-old patient with a Chiari I malformation. MRI study performed 6 years previously because of worsening headaches demonstrated a Chiari I malformation associated with a syrinx cavity. The cavity disappearance was noted after improvement of the symptoms.

Introduction L’adenome hypophysaire gonadotrope est tres rare chez l’enfant avec comme option therapeutique la chirurgie et la radiotherapie. La protontherapie, aux proprietes balistiques ultra precises, permet une radiotherapie focalisee, meme des lesions profondes avec peu d’atteinte des tissus traverses et environnants. Observation Garcon de 10 ans, sans antecedent, presentant une baisse de l’acuite visuelle soudaine avec hemianopsie bilaterale. Examen normal (P1G1). Sur l’IRM hypophysaire : volumineuse tumeur (3,5 cm) intra et suprasellaire, avec compression du chiasma et envahissement du sinus caverneux droit. L’exploration hormonale met en evidence un deficit partiel GH/TSH alors que les concentrations de prolactine, FSH et sous-unite α sont normales ; absence de mutation germinale des genes NEM1, AIP, GNAS. Chirurgie initiale de decompression puis 9 mois plus tard resection partielle pour rechute visuelle et progression tumorale a l’IRM. L’etude histologique objective un adenome gonadotrope [bFSH (4–20 %), sous unite α (40 %)] et agressif [P53 (3 %), MIB1 (6 %)]. Compte tenu du jeune âge de l’enfant, une radiotherapie par protontherapie (54 Gy) est proposee. Avec un recul de 24 mois, aucune progression tumorale est observee sur la surveillance IRM ; recuperation visuelle complete et pas d’autre deficit hypophysaire. Un traitement par GH a ete initie 1 an apres la fin de la protontherapie avec un excellent rattrapage statural. Discussion L’adenome hypophysaire gonadotrope agressif est une tumeur exceptionnelle chez l’enfant, dont la prise en charge est difficile. La protontherapie apparait une option therapeutique en postoperatoire en cas de recidive pour controler la croissance tumorale et limiter les effets secondaires iatrogenes.

Resume Les naevus geants congenitaux sont dans 1 % des cas associes a des lesions du systeme nerveux central constituant une melanose neurocutanee. Il s’agit d’une association au pronostic sombre lorsqu’elle est revelee par des symptomes cliniques. La decouverte de lesions encephaliques chez un nouveau-ne asymptomatique est actuellement plus frequente en raison de leur recherche systematique en cas de facteurs de risque. A partir d’une observation clinique d’un nouveau-ne, nous faisons le point sur cette association.

Background Patients with pituitary stalk interruption syndrome (PSIS) are initially referred for hypoglycemia during the neonatal period or growth retardation during childhood. PSIS is either isolated (nonsyndromic) or associated with extra-pituitary malformations (syndromic). Objective To compare baseline characteristics and long-term evolution in patients with PSIS according to the initial presentation. Study Design Sixty-seven patients with PSIS were included. Data from subgroups were compared: neonates (n = 10) versus growth retardation patients (n = 47), and syndromic (n = 32) versus nonsyndromic patients (n = 35). Results Neonates displayed a more severe hormonal and radiological phenotype than children referred for growth retardation, with a higher incidence of multiple hormonal deficiencies (100% versus 34%; P = 0.0005) and a nonvisible anterior pituitary lobe (33% versus 2%; P = 0.0017). Regular follow-up of growth might have allowed earlier diagnosis in the children with growth retardation, as decreased growth velocity and growth retardation were present respectively 3 and 2 years before referral. We documented a progressive worsening of endocrine impairment throughout childhood in these patients. Presence of extra-pituitary malformations (found in 48%) was not associated with more severe hormonal and radiological characteristics. Growth under GH treatment was similar in the patient groups and did not vary according to the pituitary MRI findings. Conclusions PSIS diagnosed in the neonatal period has a particularly severe hormonal and radiological phenotype. The progressive worsening of endocrine impairment throughout childhood justifies periodic follow-up to check for additional hormonal deficiencies.

We report a case of Lyme myelitis in a 31-year-old man, presenting with a conus medullaris syndrome. MRI demonstrated contrast enhancement on the pial surface of the lower thoracic cord and conus medullaris. Elevated blood immunoglobulins and IgM antibodies against Borrelia burgdorferi in the cerebrospinal fluid (CSF) were found. Leptomeningitis may be the first stage of spinal infection in Lyme disease, preceding parenchymal infection leading to myelitis. Vasculitis is probably the major mechanism. MRI findings are nonspecific and the diagnosis is given by serum and CSF analyses. Early treatment with antibiotics and high doses steroids may result in complete recovery, as in this case.

We present a neonate with a cervicofacial haemangioma complicated by the Kasabach-Merritt syndrome, respiratory distress due to airway compression and high-output heart failure. This haemangioma and intravascular disseminated coagulation, treated initially by aspirin, ticlopidine and corticosteroids, required more invasive treatment with superselective embolisation and interferon alpha-2a. The clinical outcome was good.

The phenomena that lead to modifications of polyimide, polycarbonate and polyparaphenylene irradiated by an ion beam in the 100 keV energy range are studied. A model of energy transfer based on plasmon-like collective effects occurring during the physical stage of the ion-polymer interaction, previously implemented for poly(methyl methacrylate) and cellulosic derivatives, is extended to these polymers. In the framework of this model, we carry out quantum-chemical calculations of the valence-band density of electronic states. The resulting theoretical spectrum is then compared with the experimental plasmon line obtained by electron-energy-loss spectrometry. This approach sheds light on the selective bond cleavages induced by the energy transfer at the primary physical step of the ion-polymer interaction.

Meningiomas are rare tumours in children and lumbar lesions are exceptional. We report a clear-cell meningioma (CCM) of the cauda equina in a 10-year-old girl. The tumour was diagnosed by MRI, showing an enhancing intradural mass extending from L1 to L4. Pathology and immunohistochemical study demonstrated a CCM. The patient had a recurrence 6 months after the operation requiring further surgery. CCM are rare lesions, characterised by abundant cytoplasmic glycogen particles. Complete surgical removal is necessary because, despite their benign histological appearance, CCM are potentially aggressive and may recur, spread locally and even metastasize.

In this paper, the authors present the contribution of CT and MRI to the diagnosis of acute stroke caused by arterial or venous occlusion. The term "early" used in this context means within 6 h of the onset of symptoms. Signs of early ischemic edema are subtle and sometimes difficult to detect by CT or MRI. The purpose of this presentation is to familiarize the clinician and the radiologist with the subtle brain parenchymal changes seen within the first 6 h after onset of symptoms, in order to improve detection of early ischemic infarction and to improve patient care.

Resume Les meningiomes representent 1,5 % a 4,3 % des tumeurs primitives cerebrales ou medullaires de l'enfant. Observation Une enfant de 9 ans a ete hospitalisee pour scoliose dorsolombaire. Une tumeur intracanalaire extramedullaire a ete localisee en region lombaire. Son exerese, macroscopiquement complete a permis d'authentifier un meningiome a cellules claires. Une recidive tumorale symptomatique a ete observee 5 mois plus tard, dans la meme region. Une seconde exerese a ete pratiquee, puis completee d'une radiotherapie locale. Apres un suivi de 8 mois, aucune recidive tumorale n'a ete notee. Conclusion Le caractere raide et douloureux d'une scoliose est predictif d'un processus expansif intrarachidien. L'aspect recidivant et parfois plurifocal des meningiomes a cellules claires souligne le ≪ comportement agressif ≫ de ce sous-type histologique. Une radiotherapie preventive peut etre proposee en fonction de l'âge du patient et de la localisation tumorale.

International audience; Al–Fe–O layers were deposited on silicon carbide or aluminium nitride substrates by low-pressure chemical vapour deposition (LPCVD).Aluminium trichloride, hydrogen and nitrous oxide gases have been used to generate crystallized alumina. Simultaneously, iron pentacarbonyl combined with carbon dioxide has been added to introduce iron in the alumina layers.The relation between the morphology and iron content has been studied by SEM, XPS, TEM, EELS and Mössbauer techniques. Iron concentration is studied throughout the thickness of the films. It is homogeneous around 1 at% Fe for the lowest Fe(CO)5/AlCl3 ratio and it is heterogeneous for higher Fe(CO)5/AlCl3 ratios.

Resume Le syndrome d'interruption de la tige pituitaire represente une cause de deficit en hormone de croissance de frequence non negligeable. Population et methodes. Nous avons etudie 22 enfants (13 garcons, neuf filles) âges, lors des premieres manifestations cliniques, de 2 jours a 10 ans (moyenne: 5,33 ± 2 ans). Le diagnostic de syndrome d'interruption de la tige pituitaire a ete porte sur les donnees de PIRM. La recherche des antecedents a permis de mettre en evidence une souffrance foetale dans 12 cas (54,5%), un traumatisme crânien dans trois cas (13%), une anomalie de la ligne mediane dans trois cas (13%). Les premieres manifestations on ete une hypoglycemie neonatale (deux cas), un ralentissement de la vitesse de croissance (18 cas), un diabete insipide (deux cas). Resultats. Le deficit en hormone de croissance etait complet et inaugural dans 19 cas sur 22, et isole dans quatre cas. Les deficits en ACTH et TSH etaient presents dans 15 cas sur 22. Le diabete insipide etait present dans six cas et revelateur dans deux cas. Chez tous les enfants qui avaient depasse l'âge normal de la puberte ( n = 10), il existait un deficit gonadotrope. Dans notre serie, l'intervalle libre est tres variable et ne depend pas de la cause. Conclusion. Le syndrome d'interruption de la tige pituitaire, de connaissance recente, est de frequence non negligeable; il est important de le rechercher dans les suires d'un traumatisme crânien ou d'une souffrance fœtale. Le risque est l'evolution progressive vers un panhypopituitarisme, qu'il faut rechercher regulierement.

Resume Les pseudotumeurs inflammatoires idiopathiques de l'orbite (PTIO) representent 8 % de la pathologie orbitaire tumorale de l'enfant mais ne sont que rarement decrites alors qu'elles posent de reels problemes diagnostiques. Observations Un diagnostic de PTIO a ete porte chez trois patients de 7, 13 et 14 ans dont deux se sont presentees sous l'aspect d'une myosite orbitaire aigue idiopathique (MOI). Il a repose sur l'analyse des manifestations cliniques, des donnees tornodensitometriques, de l'imagerie par resonance magnetique et des donnees histologiques. Cette analyse a ete faite en discutant la pathologie orbitaire extraoculaire maligne de l'enfant, en particulier celle du rhabdomyosarcome. Conclusion L'apparition brutale des signes orbitaires est un argument diagnostique, souligne dans la litterature, qui manque de specificite au regard du rhabdomyosarcome embryonnaire. L'existence, inconstante, de signes generaux et/ou d'un syndrome inflammatoire biologique, l'absence de lyse osseuse ont alors une valeur discriminatoire en faveur d'une PTIO. Les indications de l'examen histologique doivent etre soigneusement posees car il peut aggraver le pronostic a long terme des PTIO. La reponse a la corticotherapie peut realiser un test diagnostique mais son institution merite une reflexion multidisciplinaire.

On the basis of the Brandt-Ritchie model, we use the calculated Valence Band Density Of electronic States to explain the selectivity of the chemical modifications induced by ion irradiation in cellulose nitrate and cellulose acetate. Somes consequences pertaining to the characteristics of the valence band structure are deduced with a view to electronic applications.

2DSiC SiC composites have been elaborated with BN interphases of different thicknesses which were deposited on treated 1 Nicalon™ fibers by isothermal-isobaric chemical vapor infiltration from BCl3NH3H2 mixtures. Their mechanical behavior was investigated at 600 °C in air and compared to the results obtained on similar SiC/C/SiC composites. Although these materials exhibit similar stress and strain values at rupture when loaded at room temperature, whatever the interphase, their thermomechanical resistance depends on stress type, i.e. static or dynamic. Under static fatigue the BN interphases are more efficient than the pyrocarbon (PyC) ones. Thin BN interphases tend to maintain the interfacial properties. This result could be explained by the larger microcrack distances in the tows supporting the main part of the load, according to a lower interfacial sliding resistance. In contrast the materials with a PyC interphase, which have a much higher interfacial shear resistance at room temperature, exhibit better thermomechanical behavior under dynamic fatigue at 600 ° C. The mechanical characteristics are related to the evolution of the fibermatrix interfacial zone which has been studied by SEM, TEM and EELS.

Resume L'association d'un angiome veineux a un cavernome est rare. La survenus d'une hemorragie cerebrale doit etre attribuee au cavernome. Observation. — Un garcon de 4 ans a presente une ataxie aigue cerebelleuse. Le bilan neuroradiologique a montre l'existence d'un angiome veineux et d'une malformation caverno nateuse dans la fosse posterieure. L'enfant a ete rehospitalise a l'âge de 8 ans pour un nouvel episode d'ataxie aigue en rapport avec un hematome cerebelleux. Un traitement conservateur a ete mis en place compte tenu du risque d'infarctus veineux. Conclusion. — Les angiomes veineux sont rarement symptomatiques et sont plutot consideres comme des variantes de la distribution veineuse normale. Il n'en est pas de meme des cavernomes qui sont des malformations vraies avec un risque hemorragique. Lorsque les deux types de lesion sont associes et qu'une complication hemorragique survient, seul le cavernome doit etre enleve s'il est chirurgicalement accessible.

High energy argon ion implantation was used to form, in intentionally gold or platinum contamined silicon samples, a buried layer of efficient gettering sinks with low damage creation close to the surface. In any case, the implantation temperature was chosen to avoid partial or complete amorphization. Both nature and long term stability of these centers have been determined by Transmission Electron Microscopy (TEM) and channeling measurements. The kinetics of gold accumulation on these sinks was measured using high sensitivity Rutherford Backscattering (RBS) analysis as a function of implantation dose and annealing temperature. The effect of initial metallic contamination concentration was also investigated. The results are discussed using a model which takes into account a trapping-detrapping reaction and an impurity dependent annealing behaviour of the gettering sites.

A physical model is presented that aims at rationalizing the selectivity of bond breakage observed when polymethylmethacrylate is irradiated by ions in the 10–500 Kev energy range. This model, previously proposed by Brandt and Ritchie, is based on electronic collective effects. The coupling between the pure plasma oscillation at ωp and the oscillation of free electrons at (ω2 k0)½ makes the whole electronic population resonant at the frequency ωrp = (ω2 p+ (ω2 k0))½. By computing the valence-band density of states, we are able to calculate (ω2 k0) and then to deduce the theoretical value of ωrp. On the other hand, we provide an experimental measurement of ωrp and study its dependence on ion fluence by electron-energy-loss spectroscopy. The validity of the model of Brandt and Ritchie is then discussed in the light of both theoretical and experimental data.

Titanium and its alloys have important applications for example in aerospace or as bioimplants. Some of these applications would be improved by diamond coatings. However the large thermal expansion mismatch between diamond and titanium or its alloys creates high residual stresses, up to about 7 GPa at 800 °C, which represent an important drawback. In this study, polycrystalline diamond films were deposited on pure titanium and Ti-6Al-4V in a classical tubular microwave plasma reactor from C-H(-O)-containing gas mixtures, at a temperature in the range 600–900 °C. Raman spectroscopy provided information about the diamond grain stress, which is obviously related to the deposition temperature. X-ray diffraction indicates the presence of titanium carbide or oxycarbide. Some other characterizations by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) are reported. It is shown that XPS coupled to argon ionic etching allows us to study the first steps of the deposition process. The structure and the chemical composition at the interface of a thicker deposit are obtained by TEM and EELS.

International audience; In the CH3SiCl3-H2 CVD system, from which SiC-based films are prepared, the supersaturation of the gas phase increases when temperature and total pressure decreases and when a diffusion-controlled kinetic process is changed in a reaction-controlled one. These conditions variations seem to induce a transition from a growth regime to a nucleation regime, as evidenced by a study of the initial stages of the deposition. A transition from a crystallized film with columnar crystals to a nanocrystalline deposit is also reported on the basis of accurate experiments using TEM and related techniques.

The literature reports that neurological complications of childhood respiratory diseases due to respiratory syncytial virus (RSV) fluctuate between 1 and 40% of cases. They mostly involve central apnea - often the first symptom of infection - anoxia, and ischemic brain damage due to severe sudden weakness in infants, and seizures and consciousness disorders more or less associated with focalized neurological deficiency proving an encephalitis lesion. We report the case of brainstem encephalitis in a 7-year-old boy with RSV A nasopharyngitis, with meningitis, positive polymerase chain reaction in cerebrospinal fluid and magnetic resonance imaging (MRI) abnormalities, which was explained by viral replication encephalitis. Based on a literature review, we discuss the main aspects of epidemiology and physiopathology of the main neurological complication of RSV. Most of them have not been fully investigated and only a few articles report encephalitis. As far as central apnea is concerned, an animal experimental hypothesis surprisingly suggests a peripheral mechanism.

Aim This study aimed to report a rare clinical course of pandemic influenza A(H1N1) infection, ischemic stroke, in a 9 month-old child. Case A 9-month-old girl with no previous medical problem presented to our pediatric emergency department with high fever (39°C/102°F) lasting for 48 hours. Soon after admission, she started generalized tonic-clonic seizures that ceased after 2 injections of diazepam. Six hours later, she presented 2 short episodes of partial clonic seizures of the right arm followed by monoplegia. Lumbar puncture was normal. Noncontrast computed tomographic imaging of the brain was performed and revealed an acute infarct in the left middle cerebral artery territory with no mass effect. Electroencephalogram revealed important slowing in the left hemisphere. A magnetic resonance imaging was performed the next day and confirmed an ischemic stroke in the left posterior middle cerebral artery region. Nasal swab polymerase chain reaction was positive for influenza A(H1N1) and polymerase chain reaction detection negative in cerebrospinal fluid. She fully recovered her right-arm function on day 3 and was discharged on day 10 without sequelae. Comments Seasonal influenza is known to cause neurological complications in children. Influenza increases the stroke risk especially in adults at high risk. This is a rare event in childhood, and we believe this is the first report associated with H1N1 new variant. Conclusions Acute viral infection, notably influenza, is associated with increased susceptibility to stroke, and vaccination against influenza may reduce the risk of stroke.

Giant congenital nevi in 1% of cases are associated with anomalies of the central nervous system, which are characteristic of neurocutaneous melanosis. When neurocutaneous melanosis becomes symptomatic, it is associated with a poor prognosis. With recommended neonatal screening, asymptomatic neonatal cases are being discovered more frequently. On the basis of this observation, we consider various aspects of this association.

AlN deposits, prepared by low-pressure chemical vapour deposition (LPCVD), with or without N2O addition in the source gases, have been examined by several complementary transmission electron microscopy (TEM) techniques, including electron diffraction (ED), high-resolution electron microscopy (HREM), electron energy loss and extended energy loss fine structure spectroscopies (EELS and EXELFS), to determine both the structures and local chemical compositions. The major differences between the compounds lie in the occurrence of micro- and nanostructural changes, as dendrites and extended defects. It is suggested that the observed structural changes are induced by oxygen impurities. The implications of the results for the interpretation of some physical properties of the compounds are discussed in terms of these changes.

Apres avoir expose dans le premier article (article [R 430]) les technologies de fabrication, les principaux effets rencontres et les traitements electroniques associes, le but de ce 2 e article est d’exposer les techniques utilisees et leur realisation industrielle (ou experimentale) dans les principaux types de mesures ; ainsi, les methodes utilisees pour les mesures de pression, acceleration, vitesse angulaire, courant, detection d’agents chimiques, etc. seront developpees. Rappelons au lecteur qui n’aurait pas lu [R 430] que nous definissons par « microsystemes » des systemes a base de microtechnologie qui associent des principes mecaniques, electriques, optiques, chimiques, etc. et l’electronique de traitement. Le terme « MEMS » est utilise pour des microsystemes bases sur des principes electriques et mecaniques et les microcapteurs (ou capteurs MEMS ) sont des microsystemes dedies a la detection ou a la mesure de grandeurs physiques.

Sic polycrystalline layers were grown by LPCVD in a hot wall reactor using tetramethylsilane (TMS) diluted in hydrogen as precursor. The morphology and the structure of the films were analyzed in terms of deposition temperature, total pressure in the reactor and TMS flow rate. The layers have been characterized using various techniques : SEM, X-ray diffraction and TEM (HREM and EELS).

Aluminium nitride has been obtained by chemical vapor deposition using AlCl3 and NH3 as precursors. Progressive introduction of N2O in the gas mixture has shown the possibility of inserting oxygen in the AlN lattice. This involves strong changes of surface morphology of the deposit and the formation of less-crystallized materials. When hydrogen is added to the gas mixture, these effects are reduced. Electron energy loss spectroscopy has shown that, in this case, oxygen is mainly concentrated on the external parts of AlN crystals, the structure of which has been found consistent with the wurtzite structure.

β-SiC layers were deposited on graphite substrates in a cold-wall LPCVD reactor using tetramethylsilane diluted in hydrogen as precursor. The dependence of morphology and textures on thickness and total pressure was studied. Structural and morphological analysis were performed using SEM. TEM and X-ray diffraction.

Oxidation tests were performed (at 500

Specimens of single-crystal α-Al2O3 in the [0001] orientation have been implanted at—185°C with either 4 × 1016 Alcm−2 and 6×1016O cm−2 or with 4×1016 Fe cm−2. In both cases, amorphous layers were produced which extended from the surface to a depth of approximately 170 nm. Investigation of the response of the amorphous material to post-implantation thermal treatments has revealed significant differences. When annealed for 1 h at 960°C in argon, the material made amorphous by implantation with a stoichiometric ratio of aluminium and oxygen recrystallized into a dual-phase microstructure consisting of γ-Al2O3, a cubic transitional form, and epitactical α-Al2O3. In contrast, when treated under similar conditions, the material made amorphous by implantation with iron recrystallized completely to epitactical α-Al2O3. These differences suggest that fundamental structural and chemical differences exist in the as-implanted state. The analysis of extended energy loss fine structure (EXELFS) in electron en...

By using high and medium voltage microscopes we have been able to obtain EELS spectra showing EXELFS modulations above the K edge of low atomic number Z ~ 16, elements. These modulations supply important structural information about the local atomic environment of the absorbing atoms. After recapitulating the physical foundations of EXELFS and the ways of analysing the spectra, we discuss the main steps of the experimental technique, as developed for the medium voltage transmission electron microscope. The potential of the technique is studied for four types of specimen : graphite, hexagonal boron nitride, carbon made amorphous and cubic silicon carbide. They have been chosen to illustrate the accuracy of the method, its potential for the determination of short-range order of crystallized and non-crystallized materials and to emphasize the influence of plural scattering effects on the RDF determination.

A BN interphase has been deposited, by isothermal/isobaric chemical vapor infiltration (ICVI) from BF3─NH3, within a preform made from ex-polycarbosilane (ex-PCS) fibers, at about 1000°C. In a second step, the BN-treated preform was densified with SiC deposited from CH3SiCl3─H2 at about the same temperature. From a thermodynamic standpoint, ex-PCS fibers could be regarded as unreactive vs the BF3─NH3 gas phase assuming they are coated with a thin layer of carbon or/and silica. The as-deposited interphase consists of turbostratic BN (N/B < 1) containing oxygen. The SiC infiltration acts as an annealing treatment: (i) the BN interphase becomes almost stoichiometric and free of oxygen; (ii) the fibers undergo a decomposition process yielding a SiO2/C layer at the BN/fiber interface. The weaker link in the interfacial sequence seems to be the BN/SiO2 interface. Deflection of microcracks arising from the failure of the matrix takes place at (or nearby) that particular interface.

Les techniques de spectroscopie de pertes d’energie d’electrons (EELS) transmis par un echantillon mince, en microscopie electronique sont appliquees a l’etude microstructurale des echantillons de carbure de silicium. Deux methodes sont essentiellement considerees : L’analyse quantitative pour la determination des rapports de concentration Si/C et l’analyse EXELFS, utilisee pour la determination de l’environnement atomique local des atomes dans des echantillons cristallins ou amorphises soit par implantation d’ions chrome ou par irradiation electronique a 300 kV. Pour les deux echantillons amorphes, l’analyse EXELFS permet de mettre en evidence une organisation locale et indique une augmentation des distances interatomiques Si-C et Si-Si de l’ordre de 7 % par rapport a la structure cristalline. Elle est associee a un affaiblissement de la coordination en ce qui concerne la liaison Si-Si.

Metal Matrix Composites have several advantages over the matrix alloys, such as higher stiffness and strength, but they suffer from lower fracture toughness. This is, of course, dependent on the chemical composition of the matrix and of the reinforcement and also on the microstructure and on the processing techniques. The reactions between the different phases in the materials, in particular the matrix / reinforcement interfaces condition strength and toughness. The purpose of the present