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Resume Un depistage precoce et une prise en charge adaptee des troubles urinaires lies a la sclerose en plaques (SEP) doivent en reduire la morbidite. Une enquete transversale a ete conduite afin d’evaluer la frequence et la severite des troubles vesico-sphincteriens lies a la SEP dans une population non selectionnee et suivie en milieu neurologique aussi bien en ville qu’a l’hopital. Cent vingt-cinq patients SEP dont 44,7 % evoluaient depuis moins de 10 ans (77,6 % de femmes, âge moyen 44,4 ± 13,0 ans) ont repondu a un auto-questionnaire. Quatre-vingt-neuf patients (79,2 %) presentaient des troubles urinaires dont 42 (33,6 %) des troubles urinaires severes. Parmi les 99 patients presentant des troubles urinaires, 10,1 %, 24,2 % et 65,7 % se plaignaient respectivement de dysurie isolee, d’urgenturies/fuites isolees ou des 2 symptomes. 26,8 % des patients avec troubles urinaires ont eu des infections urinaires ayant necessite la prise d’antibiotiques (contre 4 % chez ceux sans trouble urinaire), avec un nombre moyen de 2,7 ± 2,7 infections urinaires au cours des 12 derniers mois. Seuls un quart (23,8 %) des patients ayant un trouble urinaire severe declaraient etre suivis par un specialiste, urologue ou medecin de medecine physique et de readaptation (MPR). Une majorite des patients (73,7 %) aurait aime connaitre le lien possible entre leurs troubles urinaires et leur pathologie (SEP). De nombreux patients (20,6 %) ont exprime le souhait d’avoir de l’aide pour gerer leurs problemes urinaires, notamment en cas de troubles severes (35,7 % des cas). Cette etude a permis de confirmer que les troubles urinaires sont frequents chez les patients SEP, sous-estimes et pas totalement pris en charge. Ces patients sont en demande d’information sur les symptomes et en recherche d’aide sur la prise en charge. En reponse, il nous a semble important d’informer les patients sur la frequence de la relation entre SEP et troubles urinaires, d’evaluer ces derniers regulierement avec un questionnaire specifique et de mettre en place une prise en charge adaptee selon un algorithme decisionnel bien defini en integrant le suivi par un specialiste en neuro-urologie.

OBJECTIVE: To analyze the humoral response after COVID-19 vaccination in patients with multiple sclerosis (MS) according to disease-modifying treatments (DMTs) and in comparison with the humoral response after SARS-CoV-2 infection. METHODS: We included 28 MS patients with serological results after COVID-19 vaccination (Pfizer-BioNTech or Moderna ARNm) and 61 MS patients with serological results after COVID-19 (COVID-19 group) among patients followed up at the MS Center of Strasbourg, France, between January and April 2021. The primary endpoint was the IgG index according to DMTs (anti-CD20 mAb, sphingosine 1-phosphate receptor [S1PR] modulator and other treatments) and COVID-19 vaccine or COVID-19 groups. RESULTS: In the vaccinated MS patients, the median IgG index was lower in patients treated with anti-CD20 mAb and in patients treated with S1PR modulator compared to patients receiving other or no DMTs (4.80 [1.58-28.6], 16.5 [16.3-48.5], 1116 [434-1747] and 1272 [658-1886], respectively, P

Objectives Establish recommendations for the management of UTIs in MS patients. Background Urinary tract infections (UTIs) are common during multiple sclerosis (MS) and are one of the most common comorbidities potentially responsible for deaths from urinary sepsis. Methods The recommendations attempt to answer three main questions about UTIs and MS. The French Group for Recommendations in MS (France4MS) did a systematic review of articles from PubMed and universities databases (01/1980–12/2019). The RAND/UCLA appropriateness method, which has been developed to synthesize the scientific literature and expert opinions on health care topics, was used for reaching a formal agreement. 26 MS experts worked on the full-text review and a group of 70 multidisciplinary health care specialists validated the final evaluation of summarized evidences. Results UTIs are not associated with an increased risk of relapse and permanent worsening of disability. Only febrile UTIs worsen transient disability through the Uhthoff phenomenon. Some immunosuppressive treatments increase the risk of UTIs in MS patients and require special attention especially in case of hypogammaglobulinemia. Experts recommend to treat UTIs in patients with MS, according to recommendations of the general population. Prevention of recurrent UTIs requires stabilization of the neurogenic bladder. In some cases, weekly oral cycling antibiotics can be proposed after specialist advice. Asymptomatic bacteriuria should not be screened for or treated systematically except in special cases (pregnancy and invasive urological procedures). Conclusion Physicians and patients should be aware of the updated recommendations for UTis and MS.

Objectives To establish recommendations on immunization for patients with multiple sclerosis (MS). Background Vaccines have been suspected in the past to trigger MS and relapses. With the extension of the immunoactive treatment arsenal, other concerns have been raised more recently about an increased risk of infection or a decreased effectiveness of immunization in immunosuppressed patients. Methods The French Group for Recommendations into Multiple Sclerosis (France4MS) performed a systematic search of papers in Medline and other university databases (January 1975–June 2018). The RAND/UCLA appropriateness method was chosen to review the scientific literature and to formalize the degree of agreement among experts on 5 clinical questions related to immunization and MS. Readers from the steering committee conducted a systematic analysis, wrote a critical synthesis and prepared a list of proposals that were evaluated by a rating group of 28 MS experts. The final version of the recommendations was finally reviewed by a reading group of 110 health care professionals and classified as appropriate, inappropriate or uncertain. Results Neurologists should verify the vaccination status as soon as MS is diagnosed and before disease-modifying treatments (DMTs) are introduced. The French vaccination schedule applies to MS patients and seasonal influenza vaccination is recommended. In the case of treatment-induced immunosuppression, MS patients should be informed about the risk of infection and the vaccination standards of the French High Council of Health should be applied. Live attenuated vaccines are contra-indicated in patients recently treated with immunosuppressive drugs, including corticosteroids; other vaccines can be proposed whatever the treatment, but their effectiveness may be partly reduced with some drugs. Conclusion Physicians and patients should be aware of the updated recommendations for immunizations of patients with MS.

The topic of magnetic elastomers and their properties was reorganized to clarify the host of elastomagnetic effects useful to explain the basic principles of magnetopiezoresistivity in micro-structured materials composed of magnetic particles homogeneously dispersed in an elastomer matrix. The working mechanism of the magnetopiezoresistive sensors is clarified and new results depending on the particle shape and preorientation are reported. A 20% improvement in sensor sensitivity for detecting magnetic field direction is experimentally demonstrated and qualitatively explained. The performances and limits of an optimized prototype sensor, to detect a random sequence of magnetic poles, have been investigated as a function of both the polar magnetization intensity and the poles sequence velocity. Concrete perspectives for application in MEMS devices are deduced.

Introduction En 2017, l’unite neurovasculaire (UNV) de Strasbourg a construit un programme d’education therapeutique du patient (ETP) pour les patients ayant presente un accident vasculaire cerebral (AVC) ; le programme PETAL. Objectifs PETAL veut apporter des elements de reponse aux principales interrogations des patients et de leur entourage concernant l’AVC et ses consequences afin d’ameliorer leur qualite de vie. Methodes Avec le soutien de l’Agence regionale de sante (ARS) et grâce a la volonte des differents professionnels de sante de l’UNV, le programme a ete elabore en collaboration avec l’unite transversale pour l’education therapeutique (UTEP). Des groupes de travail ont ete crees, accompagnes par un comite de pilotage compose de deux medecins, un cadre et une neuropsychologue afin de construire chaque atelier avec les professionnels de sante concernes. Resultats Le programme est en cours d’autorisation par l’ARS. Sa mise en œuvre est planifiee a partir de janvier 2018. Il se compose de 10 ateliers, en individuel ou collectif. L’equipe et composee de 21 professionnels de sante : 2 secretaires, 1 aide-soignante, 5 infirmieres, un cadre de sante, deux medecins, une orthophoniste, une dieteticienne, deux kinesitherapeutes, un ergotherapeute, deux neuropsychologues, une assistante sociale, une patiente, un moniteur en activite physique adaptee. Au total, 400 patients sont attendus en 2018. Discussion Il s’agit du premier programme d’ETP destine aux enfants et aux adultes victimes d’AVC, traitant des differentes problematiques abordees par les patients apres un AVC et prenant en compte ses consequences. A la demande de l’ARS, ce programme pilote devrait etre diffuse a l’ensemble des patients victimes d’AVC dans le Grand Est. Aucun financement n’a ete dedie. Conclusion Le programme d’ETP de l’UNV de Strasbourg est pionnier. Il espere optimiser la prise en charge des patients victimes d’AVC et diminuer le risque de recidive par une meilleure connaissance de la maladie et de ses consequences.

Red blood cells (RBCs) are the most common type of blood cell, have a biconcave disk shape with diameter of 7-8 μm and thickness of 1-2 μm, and play the fundamental role of delivering oxygen to the body tissues via the blood flow through the circulatory system [1]. RBC deformability is an essential property in the microcirculation, where the cell change their disk-like shape into a deformed one, resembling a bullet or a parachute [1,3]. RBC deformability is mainly due to the viscoelastic properties of the cell membrane, especially shear modulus and surface viscosity [1]. In this work, we report on an in vitro systematic fluid dynamic investigation of RBC suspensions flowing either in microcapillaries or in a microcirculation-mimicking silicon device containing a network of microchannels of diameter comparable to cell size. The microfluidics device is made of PDMS and is fabricated by using soft-lithography techniques. Images of the flowing RBCs were acquired by a high speed camera operated up to 1,000 frames/s. RBC membrane rheological behavior is investigated by analyzing the transient behavior of RBC shape in confined flow and by measuring the membrane viscoelastic properties in converging/diverging microchannels [4]. The time scale of the transient process is independent on the applied pressure drop and the measured value for healthy cells (around 0.1 s) is in agreement with previous micropipette data from the literature [2]. In order to study the effect of reduced deformability of the RBC membrane, the flow behavior of glutaraldehyde (GA)-hardened RBCs has been also analyzed. Hardened RBCs exhibit a faster shape evolution at higher GA concentration, thus showing that the corresponding time scale becomes shorter at increasing cytoskeleton elasticity [5]. The main results of this work is the development of a novel methodology to estimate cell membrane viscoelastic properties. Possible applications include the analysis of RBC deformability in pathological situations, for which reliable quantitative methods are still lacking.

Magnetic materials with very different saturation magnetostriction (lambda(s)) were selected: Co59Fe16Zr6CU1Nb2B16 amorphous alloy with low lambda(s) value (congruent to 10(-7)), Fe62.5Co6Ni7.5Zr7.5Cu1Nb2B15 amorphous alloy with lambda(s) congruent to 10(-5) and Tb0.27Dy0.73Fe2.0 (Terfenol) alloy with giant magnetostriction (lambda(s) congruent to 10(-3)). Magnetization intensity curves were obtained by means of a vibrating sample magnetometer from room temperature to 10 K. At low magnetizing field a reentrant magnetization behaviour was evidenced in all the investigated materials. This effect is proportional to magnetostriction value, going from a large effect in Terfenol to a small one in low magnetostriction materials. Saturation field, coercive field and hysteresis area behaviours as a function of temperature are in agreement with both the measured magnetization reentrance and stress-induced effects.

A traditional TG apparatus was modified by placing two permanent magnets producing a controlled magnetic field (TG(M): Magneto Thermogravimetry). This technique proved to be useful to study both structural relaxation and crystallisation of ferromagnetic metallic glasses. Results obtained for the amorphous alloys Fe40Ni40P14B6 and Fe62.5Co6Ni7.5Zr6Nb2Cu1B15, are reported in this paper. Structural relaxation can be evaluated by measuring changes in Curie temperature induced by thermal treatments. Crystallisation in TG(M) is detected through a change in the measured apparent mass (difference between the sample mass and magnetic force driving it upward). These results were confirmed by DSC analysis. Whether the obtained crystalline phase is ferromagnetic, it can be identified through its Curie temperature, measured by TG(M). In fact the value of 770degreesC measured as Curie temperature of crystallised Fe62.5Co6Ni7.5Zr6Nb2Cu1B15, led to conclude that the only ferromagnetic crystalline phase is alpha-Fe. These hypothesis was confirmed by XRD analysis, showing that the first crystallisation yields to alpha-Fe nanocrystals.

The effects of heat treatments in vacuum on magnetic permeability, Young's modulus and magnetoelastic wave amplitude were investigated in the amorphous ferromagnetic alloys Fe73.5Cu1Ta3Si15.5B7 and Fe73.5Cu1W3Si15.5B7 where tantalum or tungsten replaces niobium, which mas generally used with the same atomic fractions of the other elements. The stress sensitivity coefficient was also theoretically deduced in its development vs. the applied magnetic bias field. Structural relaxation and crystallization consequences are evidenced. Moreover an already predicted relation between the maximum of magnetoelastic wave amplitude and the minimum of stress sensitivity coefficient was confirmed.

The role of magnetoelastic energy to determine the causes which affect the magnetic anisotropy are reviewed. The simple model used to describe magnetostriction in the new nanostructured materials is reported. Starting from this model the magnetostriction in multilayer samples, of the kind magnetic material/non-magnetic material, is discussed. In particular the fundamental influence of the interlayers is shown. Finally it is demonstrated that by measurement of saturation magnetostriction it is possible to have information on the interlayers thickness and average composition.

The magnetic susceptibility during hysteresis cycles was measured in both amorphous and crystalline metallic ribbons. The analysis of the dependence on magnetizing field evidences a different behaviour due to the structural differences. The fundamental importance of the amplitude of the magnetizing field used for dynamic evaluation of initial susceptibility is demonstrated and related to the measured effects as well. Moreover, both temperature and frequency effects on the initial susceptibility confirm some peculiar properties related to the amorphous character.

Multilayered amorphous ribbons were produced by electrolytical deposition. They have exceptional magnetoelastic properties which enhance the amplitude of longitudinal magnetoacoustic waves travelling in the samples, also in comparison with similar-size ribbons of conventional metallic glass obtained by rapid quenching from the melt.

ypical Fe–Si sheets were cut using various techniques, reducing the material to ribbons having their grains oriented parallel to the longitudinal axis. The magnetic and magnetoelastic properties in this direction reveal differences in the effects produced by conventional mechanical cutting in comparison with laser cutting. In particular, the latter technique results in both the highest saturation magnetisation level and the lowest values of coercive field, hysteresis loss, and saturation magnetostriction. It can be inferred from the results that laser cutting is effective in decreasing both induced stresses and defects on the cut edges.MST/1446

The high-frequency initial magnetic permeability and its relaxation have been studied in Fe62.5Co6Ni7.5Zr6Cu1Nb2B15 after heat treatment (both in furnace or via DC Joule heating). The magnetic permeability steadily increases in correspondence of both structural relaxation and nanocrystallisation of the alloy. The intensity of the permeability relaxation (measured between fixed times after demagnetisation) is reduced by structural relaxation but exhibits a sharp maximum immediately before the onset of nanocrystallisation. The nanocrystalline alloy is characterised by a nonzero, if reduced, permeability relaxation.

A previos thermal model for the heat treatment of a little metal ribbon, moving under a broad laser beam with Gaussian intensity distribution, is elaborated in order to apply it also in the opposite experimental condition, namely for sample width higher than the laser spot. The temperature value vs. the distance from the symmetry axis of the treated zone is determined as a function of both the sample displacement rate and the laser power. When structural and magnetic-property modulation is produced in the transverse direction of a glassy metal ribbon, the experimental results, concerning both reduced magnetization as a function of the temperature and structure changes, are in agreement with the thermal-model predictions.

Introduction Le reseau LORSEP (reseau lorrain de prise en charge de la sclerose en plaques) etend sa prise en charge aux patients atteints de sclerose laterale amyotrophique (SLA). Objectifs Fort de son experience de 10 ans (2004–2014) dans la sclerose en plaques, pathologie chronique invalidante, les membres du reseau ont progressivement ete a amenes a proposer leurs competences aux patients atteints de SLA. Methodes Ce travail decrit la prise en charge qu’effectue le LORSEP, reseau de sante ville-hopital, destinee aux patients atteints de SLA et a leur famille. Le centre SLA labellise du CHU de Nancy a ete amene a solliciter le reseau LORSEP, en particulier, la psychologue et l’assistante sociale, ainsi que, plus ponctuellement la neuropsychologue pour une prise en charge specifique et adaptee des patients SLA. Son originalite tient a la continuite de la prise en charge en dehors des visites trimestrielles programmees a l’hopital. Resultats Les resultats quantitatif et qualitatifs de l’activite des membres du reseau LORSEP intervenant dans la prise en charge de la SLA sont presentes dans ce travail. La SLA semble un modele de maladie necessitant une prise en charge associant une filiere de soins coordonnee par les centres de reference/competence mais aussi les reseaux ville-hopital. Discussion La file active du centre SLA est de 125 patients. Le nombre d’interventions de l’equipe du reseau est bien superieur et temoigne de la pertinence et de la necessite de la prise en charge pluridisciplinaire relayee par des partenaires exterieurs a l’hopital, comme les reseaux de sante ville-hopital. Conclusion L’organisation de la filiere de soins des patients atteints de SLA est presentee en insistant sur la complementarite entre le centre SLA labellise du CHU de Nancy et le reseau de sante LORSEP.

Introduction Le registre Lorrain de la sclerose en plaques (SEP) recueille des donnees cliniques et paracliniques des patients lorrains et permet de connaitre la prise en charge therapeutique des patients lorrains. Objectifs Donner une photographie des habitudes des neurologue lorrains en matiere de traitement de fond selon la forme de la maladie : CIS (syndrome cliniquement isole), forme remittente (RR), primaire et secondairement progressive. Methodes Le registre Lorrain de la sclerose en plaque a ete interroge sur la repartition des traitements de fond de la SEP en fonction de la forme de la maladie. Les donnees sont extraites au 1er janvier 2015. Il s’agit d’une analyse transversale. Resultats Cinq mille trois cent trente-trois dossiers sont examines : sur les 2214 patients en forme RR, 48 % sont sous immunomodulateur et 19 % sous immunosuppresseur. Pour les 1356 patients en forme secondairement progressive (SP), 11 % est sous immunomodulateur, 21 % sous immunosuppresseur et 60 % ne recoit pas de traitement de fond. Alors que 70 % des 589 patients en forme progressive primaire (PP) n’ont pas de traitement de fond et 17 % est sous immunosuppresseur. Cinquante-quatre pour cent des 484 patients CIS n’ont pas de traitement. Trente-huit pour cent est sous immunomodulateur. Discussion L’analyse de la prescription des traitements de fond reflete l’offre therapeutique dans le respect des AMM bien que quelques nuances puissent etre apportees. La proportion de patients traites au stade de CIS depend du diagnostic de SEP pose ou non selon les criteres de Mc Donald. Pour les autres formes evolutives, le traitement de fond est souvent prescrit en respectant la logique des nouveaux criteres de Lublin et Reingold (Neurology, 2014). Conclusion L’analyse de la prescription des traitements de fond en lorraine reflete le plus souvent l’offre therapeutique dans le respect des AMM avec des surprises concernant les patients RR non-traites et les patients SP et PP traites. Informations complementaires Trente-cinq pour cent des patients RR se sont pas traites de 30 % et des patients SP et PP le sont.

Elasticity moduli at constant magnetic field and at constant induction as the functions of magnetic bias field of the strips of Fe/sub 20/B/sub 12/Si/sub 8/ metallic glass annealed in vacuum at temperatures of 370 and 380/spl deg/C were investigated. The values of moduli in as-quenched state were changing from 133 to 155 GPa. After annealing at 370/spl deg/C the moduli changes were from 80 to 170 GPa and after heat treatment at 380/spl deg/C /spl Delta/E effect increased and these changes were from 60 to 170 GPa. >

Interaction between acoustic field and electromagnetic field, in a magnetostrictive ferromagnetic material produces both transversal quasiacoustic waves (QACW) and quasielectromagnetic waves (QEMW) named hybrid waves. Properties of hybrid waves have been studied and their dependence on conductivity has been emphasized in the piezomagnetic case. To this end, the system of Maxwell’s equations, Newton’s law of force, and piezomagnetic state equations were solved for an infinite continuous medium. It is shown that for a particular conductivity value σc, the hybrid modes coincides in a mixed propagation mode we called MHWM. The dispersion relation, in the case of separate hybrid waves, as well as in the mixed mode MHWM, is discussed. The MHWM has a velocity Vc, which is independent of wave number k. Moreover we point out that (a) for very high σ, the QEMW velocity reaches a k‐independent value while the QACW velocity falls to zero, (b) the behavior of σc(k), at constant Vc, is linear, (c) for σ≠σc, at constant...

We have produced ribbons of Co1-xPx (x almost-equal-to 0.09) with the coexistence of microcrystalline and amorphous structure. These kind of materials have different magnetic and magnetostrictive behaviour in comparison with that already known of crystalline or amorphous specimens (x almost-equal-to 0.05 and 0.12, respectively). In particular we demonstrate the obtaining of good magnetoelastic response and, at the same time, the results validate the structure sensitivity of resonant magneto-acoustic waves. The complete behaviour of wave amplitude as a function of the applied magnetization field is compared for each sample and explained.

We sought to evaluate the application of the French law for the protection of persons participating in research studies in biology and medicine. Specifically, we examined comprehension and consequences of informed consent procedures in the field of stroke, characterized by an emergency setting, cognitive impairment and poor prognosis.Patients (or proxies) included in recent years in clinical studies conducted in our Neurology Department for evaluating treatment of acute phase cerebral ischemia were interviewed to determine their knowledge of the disease, its treatment, the study protocol and the legal regulations, and the affective and psychological consequences of the informed consent procedure.Among 72 patients included in 7 studies ([fibrinolytic agent: 3 (n = 43), anticoagulant agent: 1 (n = 4), neuroprotective drugs (n = 25)], [7 randomized studies, 6 double-blind versus placebo, 5 with a 6-hour inclusion time interval]), 15 died during the acute phase, 5 were lost to follow-up, 4 refused to participate and 7 gave very partial answers. Consent was signed by the patient in 15% of cases, the spouse in 50%, a descendant in 23%. These persons were aware of the spontaneous risk of death (85%) or definitive functional impairment (95%). Half of them thought a specific treatment existed, 11% had some idea of the mechanism of action of the proposed treatment while 67% learned about this mechanism from the information provided. Although they had received information, only 25% of the patients had knowledge of placebo and 7% of therapeutic risk. 37% expected complete recovery from the treatment, 44% partial recovery, and 13% were very disappointed by the outcome. 81% felt they were free to make their own decision. Although 86% did not know there was a law protecting them, 82% were in agreement with the requirement for their consent while 17% would have preferred to delay consent. Most wished to be given the opportunity to discuss the study again, after the acute phase, and to receive the results of the study.This study shows that most French stroke victims and their closest relatives are unaware of the law protecting persons in biomedical research and have poor knowledge of medical data after being given appropriate information. Even so, the quality of information increases the quality of the patient-physician relationship. Patients want to be free to make their own decision to consent to biomedical research, but their desire was more for good information than for the power to make their decision alone. Being asked to give informed consent in order to participate in a clinical study accentuates the affective and psychological consequences of stroke, a factor which should be taken into consideration during follow-up.

Co/Cu multilayers were produced by means of sputtering in order to obtain a constant Co layer thickness while the Cu interlayers had variable thicknesses. The Cu layer thickness was always greater than 15 Angstrom in order to produce magnetically decoupled Co adjacent layers. We have observed that by varying the Cu layer thickness an effect is produced on both the magnetic differential permeability and the stress sensitivity in the plane of the films. In particular, the differential permeability is reduced upon increasing the Cu interlayer thickness and the stress sensitivity displays a maximum as a function of the applied compressive stress. The effects are tentatively interpreted in terms of the presence of a coherent interface between adjacent layers. By relating the maximum in the stress sensitivity to the average internal stress, we have evaluated the interface thickness.

Experimental evidence of magneto-elastic wave amplitude enhancement by thermo-elastic waves is reported. This enhancement is shown to be optimized under resonance conditions. The thermo-elastic waves have been excited in a metal alloy ribbon sample by a high repetition rate CO 2 laser. The results are explained in terms of a simple theoretical treatment of the thermo-magnetic elastic waves under the conditions investigated.

The piezomagnetic coupling coefficient (the <>) is quantitatively investigated below room temperature and a comparison is made among polycrystalline samples and amorphous ones. The technique used is an original one. It experimentally consists in the measurement of the amplitude of magnetoelastic waves, their resonance frequency and differential susceptibility; theoretically, it consists in coupling Newton's law of force with the piezomagnetic state equations. The results clearly show different responses of polycrystalline samples with respect to the amorphous ones; in particular the nonmonotonic behaviour of the <> for metallic glasses is interesting for establishing their actual magnetic states at low temperature.

The actual knowledge on Co-P electrodeposited alloy is reviewed. The differences among the experimental conditions of production, and their influnce on the obtained material as well, are discussed. Recent results both in microcrystalline layers and in amorphous multilayers are reported. In particular the attainment of not-trivial magnetoelastic properties is emphasized.

Fe1-xCux powders were ground down by ball milling. After a particular milling time, for x congruent-to 0,95, the production of fcc crystalline phase, Fe1-yCuy (y > 0,5), was evidenced by the changes in magnetic properties, X-ray and Mossbauer spectra.

Powders of iron-vanadium, in equiatomic proportions, and pure iron were ground down by high-energy milling for different times. The evolution of the magnetic properties was investigated by the flux measurement technique. On increasing the milling time we observed the effects of particle size change and interatomic intermixing which were checked by Mossbauer spectroscopy and X-ray diffraction. After 48 h of milling, the structure and magnetic results agree in proving that an amorphous phase develops in the FeV system. Moreover, at low milling times (

Mossbauer spectra, susceptibility and magnetization measurements were performed on Fe 40 Ni 40 P 14 B 6 amorphous ribbons. The results indicate the existence of correlated ferromagnetic regions of different sizes. With decreasing temperature a collective freezing of the resulting moments occurs with cluster-glass-like characteristics.

The behaviour of low field magnetization versus temperature is strictly dependent on phosphorus atomic fraction in Co 1− x P x alloys, namely on the structure of the material. In particular the presence of a transition to reentrant magnetization at low temperature is validate and its relation with the degree of disorder demonstrated.

We studied some kinetic, fluid-dynamic and electrical problems arising in the numerical modelling of a c.w.TE high power CO2 laser operating with N2, He and CO additives. We adapted a five-temperature pulsed laser model to the c.w. case by coupling a set of fluid-dynamic equations to the kinetic set. We added the rate equation for the secondary electron density. We calculated in some detail the ionization term and fitted experimental results to determine attachment and recombination coefficients in the discharge chamber. In order to solve our equations a numerical code has been developed. By this means we investigated the effects of temperature, density and velocity variations in the flowing mixture on the small signal gain of the device. We obtained profiles in the laser chamber of the sustainer current, small signal gain and fluid-dynamic parameters. A simple (Fabry-Perot) optical cavity model has been used to calculate output power and electrical efficiency of the device. A comparison of numerical code predictions and experimental results is presented.

A contribution to the investigation of the stress effect on the saturation magnetostriction of polyerystalline rods stressed by torsion is presented. The critical torsional stress above which magnetostriction remains constant is found and the crystal anisotropy level, at various torsions, is estimated. As in the tensional case, the effect of crystal anisotropy at the critical stress has not been clearly interpreted so far. A study of the behaviour of the magnetization curve near saturation provides a possible explanation.