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En preliminaires au developpement d'une technologie MOS complementaire submicromique, la fiabilite de bandes d'aluminium de 1,5 a 8 μm est etudiee et comparee avec de nombreuses techniques. En particulier, la methode resistometrique est comparee a la technique du temps moyen avant cassure pour les plus fines bandes

Till now it was usual to think that the physical degradation of the end-spray contacts of metallized polyester capacitors, accelerated by exposure to high temperature, only implied an increase of the equivalent series resistance. This paper reports that together with this resistance increase, a contribution due to a parasitic capacitance must be taken into account to describe this degradation mechanism correctly. A degradation model is presented that enables fairly good fitting of experimental measurements of capacitance, dissipation factor and impedance vs. frequency of capacitors submitted to long-term tests, that exhibit an electrical behaviour deviating from the one described by the usual equivalent series circuit. The paper illustrates a technological analysis method that enables the consistence of the proposed model to be confirmed and that can currently be used to make quick estimations of the reliability performance of components by different manufacturers and to carry out periodic quality control. It was also seen that, in well manufactured capacitors, the described degradation mechanism is rather slow, with respect to the high temperature exposure time, so that the reliability level of these components is not affected.

After the introduction in diagnostic imaging of CT and US beside sialography (SG), today it is possible completely evaluate the ductal system as well as the parenchima of the parotid gland. The authors examine the results and limitations of these new imaging modalities, outlining their role in the evaluation of parotid masses. Echography, because of high sensitivity, seems to be the method of choice for the first approach to this pathology, while sialography and CT can be successful in some circumstances: the first allows to easy outline the inflammatory involvement of the gland, while CT seems to be essential for the study of deeply situated tumors and for a complete spatial evaluation.

Three cases of demoplastic fibroma of bone are presented. Thirty six cases already reported in the world literature are reviewed, making the present total thirty nine cases. The extreme rarity of the tumor is emphasised, and its clinical, radiographic, morphological and pathological aspects discussed. Though the absence of metastases or histologically abnormal cells attest to its benign nature it has a definite tendency to local recurrence. Differential diagnosis and treatment are discussed.

Idiopathic osteonecrosis of the femoral head presents many problems of diagnosis and treatment during the early stages of the disease due to the paucity of clinical manifestations and the absence of radiographic evidence. By the time that the radiographic and clinical evidence are sufficient for a reliable diagnosis, the disease is so advanced that treatment is a problem. Early diagnosis is therefore the key issue and, in this context, instrumental tests, CT scanning and the measurement of blood flow velocity play an ever-increasing role. In the early stages of the disease CT scanning shows characteristic changes in the socalled "asterisk sign" of Dihlmann, and this has proved useful not only in terms of diagnosis, but also in order to initiate early treatment of the disease. Although radioisotope methods with double tracer do not allow for direct visualisation of the circulation in the femoral head, they have proved to be extremely reliable in evaluating the perfusion index of the femoral heads by providing activity/time curves which are a reliable estimate of regional blood flow.

The radiographic criteria are described for the evaluation of total hip replacement. The authors' purpose is to uniform all different parameters for a correct long-term radiographic follow-up. The basic radiographic parameters are pointed out for the assessment of eventual loosening/wearing out of prosthetic material: 1) correct positioning of the acetabular and femoral components; 2) initial wearing of the plastic; 3) state of the bone-cement, bone-implant attachments. These criteria represent the base for a prognostic evaluation of the implant, for they allow the quantification of the radiographic changes (sinking, demarcations, fractures of cement, loosening etc.) during time.

The authors present a case of intraosseus lipoma seen at the Orthopaedic Clinic of the University of Bari, bringing the total in the world literature to thirty cases. The tumour is a benign primary neoplasm of bone, made up of mature adipose tissue containing atrophic bone trabeculae. This affection is a definite entity quite distinct from parosteal lipomas arising in periosteum, fasciae and muscles which only affect the bone secondarily by compression or direct invasion. Emphasizing the extreme rarity of the tumour, the authors discuss its clinical, radiological, anatomical and pathological features. The differential diagnosis is with certain dysplasic and neoplastic lesions of bone such as: bone cyst, non-ossifying fibroma, aneurismal cyst, monostotic fibrous dysplasia, and solitary myeloma. Complete removal is followed by cure.

The results of surgery in the treatment of osteonecrosis of the femoral head are analysed and discussed. Medullary decompression by the forage biopsy technique in the early stage facilitates normalisation of the intramedullary pressure and breaks the vicious circle constituted by ischaemia-oedema-increased medullary pressure-ischaemia which eventually produces bone death. Flexion osteotomy is indicated in the advanced stage (Ficat stage 3) provided certain parameters are respected such as the age of the patient, the stage of the lesion, the extent of the necrosis and the absence of secondary arthritis. For cases classified as Ficat stage 4, the only solution is total arthroprosthesis.

The Italian Fixed-Point Observatory Network (IFON) integrates well-established coastal and ocean infrastructures (buoys, platforms, moorings, mast platforms, etc.), most of them providing realtime multidisciplinary monitoring for a number of marine and atmospheric variables. Here, we describe the network characteristics and then discuss an example of its operation during the cold spell of winter 2012. One of the goals of the Italian Flagship Project Ricerca Italiana per il mare (RITMARE) is to create a common, validated IFON database able to fulfil both public and private demands, including validation of remotely sensed data and numerical models, environmental planning and management, and time-series analysis of climate and oceanographic data.

This work compares the results of 2 different techniques of anterior cruciate reconstruction performed by 2 surgeons with the same rehabilitation program and same criteria of results evaluation. Forty-five patients were operated on using semitendinous tendon autograft, (average followup, 8 years 4 months), and 30 patients using bone patellar tendon bone autograft (average followup, 7 years 5 months). Functional results were evaluated using the Lysholm and Tegner rating systems, and clinical laxity or stability were evaluated using the Lachmann and Jerk tests. Articular stability and function were significantly better in the patients operated on using bone patellar tendon bone autograft.

The PIT AGEM project includes bi-monthly water monitoring, platform monitoring, and primary production and biogeochemical characterization of the Gulf of Manfredonia (southern Adriatic Sea). The bi-monthly monitoring consists of continuous, horizontal tracking of surface physico-chemical parameters (temperature, salinity, dissolved oxygen, pH, in vivo fluorescence and turbidity), and vertical physico-chemical profiles and sub-surface and bottom water sampling for suspended solid and nutrient (N-NH3, N-NO2, N-NO3, P-PO4, Si(OH)4) analyses. The platform provides meteorological data and high frequency monitoring of temperature, salinity, dissolved oxygen, fluorescence, turbidity and compounds of N and P at 5 depths. Two oceanographic cruises are planned to provide information on primary production and biogeochemical cycles of nutrients in sediment and in the water column. At this stage, the boat monitoring and the platforms are still being tested, however, the first of the two cruises was completed on October 2002. This paper shows the program and some preliminary results.

The width of the weight-bearing surface (WBS) of the acetabulum and its obliquity; height, width, opening angle and alpha angle of the gothic arch; diameter of femoral head; the angle between the center of the femoral head and the most lateral point of the acetabulum (CE angle); neck-shaft angle (CCD angle); offset; angle of aperture, surface area, and volume of the spherical sector; radius and height of the spherical bowl; and distance from teardrop were assessed to study mechanically normal and frankly osteoarthritis hips. There appears to be a direct correlation between primary alterations of the above variables and development of osteoarthritis of the hip.

The genus Tovomita (Fam. Clusiaceae) comprises 45 species mainly found in tropical regions of Central and South America. Most of the species of the title genus have been used for centuries as natural remedies. Phytochemicals isolated from Tovomita spp. include prenylated and unprenylated benzophenones and xanthones. The aim of this review is to examine in detail from a phytochemical and pharmacological point of view what is reported in the past and current literature about the properties of phytopreparations and individual active principles obtained from plants belonging to the Tovomita genus.