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AbstractRadiocarbon measurements on the carbonaceous aerosol fractions are an effective tool for aerosol source apportionment. For these measurements, a new sample preparation line (MISSMARPLE: MIlan Small-SaMple Automated Radiocarbon Preparation LinE for atmospheric aerosol) was built in Milan (Italy). MISSMARPLE can separate different carbon fractions (i.e. total carbon (TC), elemental carbon (EC)), automates the sample combustion processes and the CO2isolation in the “combustion line”, and was designed to handle small samples, of about 50 μg carbon. The CO2obtained in the combustion line is then reduced to graphite in the graphitization line for subsequent accelerator mass spectrometry (AMS) analysis at the INFN-LABEC in Sesto Fiorentino (Italy). MISSMARPLE was tested for reproducibility of 14C/12C ratio in primary standard samples, for background contamination by the analysis of blank samples (graphite with zero percent Modern Carbon (pMC)), and for accuracy by the analysis of IAEA-C7 for pMC(TC) and NIST RM8785 for pMC(EC) used as secondary standards. Measurements were carried out in different AMS runs. Reproducibility of 14C/12C was within 1.2%; blank values were down to 2.2 ± 0.2 pMC in the latest AMS run, and both IAEA-C7 and NIST RM8785 measurements were within 1σ with the reference value (but for one IAEA-C7 sample within 2.3σ). These results point to MISSMARPLE as a new, valuable tool for aerosol sample preparation for radiocarbon measurements to be exploited not only on traditional 24-h samples but also when small carbon quantities are available (e.g. collected at remote sites or with high temporal resolution).

This article presents results relating to the production of a WC-Co gear cutting tool via selective laser melting (SLM). The influence of powder grain geometry and chemical composition on SLM process outcomes are firstly investigated by producing and testing simple cylindrical specimens, from which optimal process parameters and scanning strategies are establish for both the component itself and supporting structures. These parameters are then utilised to produce a real cutting tool that is subsequently employed for internal automotive gear fabrication.

Information drawn from national engineering magazines, a nationally distributed newspaper, and a statewide newspaper in Kentucky is presented for 114 bridge failures in the continental U.S. Failures during the construction stage and bridges that were closed in order to avoid failure were not considered. Of the 35 bridge failures reported in the Kentucky newspaper, only one was reported nationally. The study of this literature indicates that the principal source of bridge failures in the United States involves ships, trains, trucks, and cars colliding with the structures. In Kentucky, trucks exceeding the posted weight limit appear to be the major cause. Due to the scattered nature of the information, the formationn of a new division of the Federal Highway Administration or the National Transportation and Safety Board should be considered, whose mission would be to gather data and identify potential deficiencies in bridge design and construction.

The pressure vessels are used to contain fluids that are at a pressure that is significantly different from the atmosphere. İn the present study, multiple carbon fibre reinforced composite pressure vessels were modelled in ANSYS with the variation of the fibre orientation angle. Internal pressure was applied to the pressure vessels, then it was considered to be failed if the first ply burst failure was occurred. The Tsai-Hill failure criterion was applied to the model. The fibre orientation angle of 55°/-55° was found to have good strength. The deformation modes changed from the lateral deformation at lower fibre orientation angles to the axial deformation at higher angles. For axial loading the lower fibre orientation angle has better strength. The fibre orientation angle of 30° showed better properties for the axial loads. For the combination of the axial and the internal pressure as the load, the 55° orientation angle showed better resistance.

The clinical conditions of 110 patients affected by myasthenia gravis (MG) were followed from two to twelve years. Patients with thymectomy showed a statistically higher percentage of clinical remissions than patients without thymectomy. In patients without clinical remission immunosuppressive drugs were prescribed in different schedule; the greater percentage of pharmacological remissions with less adverse effects was obtained with administration of prednisone 50–75 mg/die initially, than gradually reduced to smaller dosage in alternate day, associated to azathioprine. Plasmapheresis, performed in six cases not responders to immunosuppressive drugs, always showed a positive and even prolonged effect.

Abstract: A knowledge-driven approach to the three-dimensional reconstruction of coronary artery trees by means of two X-ray projections is proposed. The spatial reconstruction of the tree skeleton is discussed. A binary tree model of the arterial structure and its projections is employed. Consequently, the reconstruction of the three-dimensional tree skeleton is achieved by (a) matching the skeletons of corresponding pairs of vascular segments in the two views and (b) back-projecting the coupled skeleton projections. From a geometrical point of view, the matching problem is, in general, ill-conditioned. For this reason, additional information sources were used. Thus, the matching phase is accomplished by using both the imaging geometry information, as well as anatomical and topological knowledge, about the coronary arteries coded in a rule base. As far as the back-projection phase is concerned, an algorithm was developed based on: (1) the imaging geometry, (2) the bounding of the back-projection error and (3) a contiguity criterion.

Abstract: Image analysis by video systems is well established for medical applications, and its has been successfully used for the analysis of cineangiograms. In most instances the instrumentation used for this purpose has been characterised by relatively complex hardware set ups. Owing to the interest of this application, also in relation to the progressive growth of cardiac surgery and hence the need for anatomo-functional diagnosis, it seemed reasonable to consider the possibility of simplification and standardisation of the instrumentation, taking advantage of the software possibilities of a small digital computer and possible microprocessor implementation. The paper presents a minimum system capable of processing t.v. images, using an unexpensive computer interface and a general-purpose software package.

Resume Etude des modifications histologiques de l'appareil neurosécréteur céphalique en fonction de l'activité de ponte.

The quantitative EMG technique was used to detect Duchenne muscular dystrophy carriers. The tests were carried out, measuring the parameters of M.U. potentials (the duration, the phase, and the Ø index according to Van den Bosch, modified by Gardner-Medwin), and using the Willison analyzer, in a group of carriers and normal subjects. Ten M.U. potentials from the deltoid, biceps brachii and quadriceps muscles were photographed and measured in each subject, and the right and the left biceps were examined with the Willison analyzer. An high detection rate was obtained by manual EMG, measuring traditional values such as mean number of phases, A.P. duration and Ø index. The Willison analyzer was significant in 2 known carriers. The total EMG detection rate was higher than the CPK tests both in the known carriers and in the possible carriers. It is concluded that the quantitative EMG technique is an useful and specific test to detect carriers of the gene of Duchenne muscular dystrophy.

A case of progressive extrinsic ophthalmoplegia associated with peripheral neuropathy and hypertriglyceridemia type IV is described. Motor and sensory conduction velocities of the spinal nerves were severely decreased, while the EMG of the facial muscles was more suggestive of a myopathic disorder.

The assessment of skeletal maturity is crucial for the analysis of growth disorders and plays an important role in paediatrics. For this reason, several methods have been developed for estimating skeletal maturity. Among them, the Tanner and Whitehouse method (TW2), which is based on the analysis of hand radiographs, is usually considered the most accurate and reliable. Nevertheless, TW2 is applied only in a small fraction of cases, due to its complexity and long examination times. Thus, the development of automated systems which reliably implement this method is highly desirable. However, major difficulties have been found in the development of computer-based systems for the assessment of skeletal maturity. In particular the extraction of the bones of interest has proved to he extremely challenging. In this paper, we propose a system architecture for the implementation of the TW2 method, which is based on artificial neural networks. For each bone considered, the maturation stage is determined by means of a two-step process which first locates the position of the bone in the radiograph and then analyzes the bone shape. Experimental results obtained with our implementation of the carpal version of TW2 are in good agreement with those provided by trained observers. Copyright 1995, 1999 Academic Press

The clinical, immunological and neurophysiological data on 54 patients with idiopathic inflammatory polyradiculoneuropathy (IIP) are reviewed in order to reach a correct diagnostic and therapeutic approach. 49 of these patients presented acute and 5 recurrent IIP. Of the acute cases 10 patients had a severe course with paralysis of all limbs and respiratory insufficiency, and 3 died. An increase in CSF total proteins and impairment of nerve motor conduction velocities proved to be valuable tests for the diagnosis of IIP; these tests usually become more significant after 2 or 3 weeks of illness. Steroid treatment did not prove to be effective, while two patients with acute and progressive IIP, subjected to plasmapheresis, showed rapid and steady improvement. In these two patients the plasmapheresis was associated with azathioprine.

A 48 year old man, irradiated 30 years before for a left laterocervical, lymphadenopathy, developed a progressive weakness of the left arm of two years duration. Myelography and other examinations excluded a compressive spinal process. The clinical and neurophysiological data point to a lesion in the spinal gray matter, probably due to the previous radiation treatment.

Six cases of Ophthalmoplegia Plus (OP) have been studied: all the patients had palpebral ptosis, ophthalmoparesis and descending myopathy. Hypoacusia, cardiac conduction impairment, small stature, mental deficit and vestibulo-cerebellar dysfunction were present only in some cases.

Single PCB congeners were determined in dated sediment cores taken from the three greatest Italian lakes. The PCB profile is fairly constant with time in the three lakes and similar to that of a mixture of Aroclor 1254 and 1260 (35 : 65). Qualitative and quantitative results are consistent with the amounts of Aroclor sold, showing a general trend towards less in recent sediments than in the 1970s. However, this decrease was sharper in Lakes Maggiore and Como, which in the past had PCB concentration peaks of 197 ng g-1 and 822 ng g-1, repectively, than in Lake Garda (peak 38 ng g-1). There is disequilibrium between the top sediment layer and the water column due to freshly settled algae, which can adsorb PCBs to a greater extent than can abiotic particulate matter. A comparison of PCB loads in rain and in sediment shows that there are still local sources of contamination in Lake Como. The net flux of less chlorinated PCBs from Lake Maggiore to the atmosphere indicates that this waterbody can be a source of pollution for the surrounding area.

This paper describes a physically inspired method for the recovery of the surface of 3D solid objects from sparse data. The method is based on a model of closed elastic thin surface under the action of radial springs which can be considered as the analogous, in spherical coordinates, to the well-known thin plate model. The model is a representation for whole-body surfaces which has the degrees of freedom for representing fine details. We formulate the surface recovery problem as the problem of minimizing a non-quadratic energy functional. In the hypothesis of small deformations, this functional is approximated with a quadratic one which is then discretized with the finite element method. We provide steepest-descent-like algorithms both for the case of small deformations and for that of large ones. Then we introduce a representation of our model in terms of its free deformation modes. This representation is extremely concise and is therefore suited for shape analysis and recognition tasks. Finally, we report on the results of experiments with synthetic and real data which show the performance of the methodCopyright 1994, 1999 Academic Press, Inc.

Seventy-nine women known as, or suspected to be, carriers of the Duchenne type of muscular dystrophy were examined. The 15 known carriers had an estimation of the CPK serum level and a manual quantitative EMG, which gave the high detection rate of 93%. The 64 suspected carriers had CPK determination and quantitative EMG, or CPK and muscle biopsy, and the value of each technic is discussed. The problem of giving a reassuring answer to women considered to be possible carriers on genetic criteria, but who are not really carriers, is solved if the results of all three tests are negative.

In a follow-up study of 128 myasthenic patients from a neurological center in Northern Italy, three were found to have developed glomerulonephritis at variable intervals after the onset of myasthenia gravis, thymoma (two patients), and thymectomy. By renal biopsy, two patients (cases 1 and 3) were found to have membranous nephropathy; and one (case 2), pauciimmune extracapillary glomerulonephritis. At follow- up, patient 1 was persistingly nephrotic and developed renal failure, and patient 3 only had urinary abnormalities. Patient 2 developed end- stage renal disease. The review of the literature showed 10 other cases of glomerulonephritis associated with myasthenia gravis with or without thymoma and thymectomy. Therefore, it is likely that these conditions are pathogenetically linked. The role of autoantibodies, thymoma, and thymectomy in favoring glomerulonephritis in myasthenic patients is discussed. (Am J Kidney Dis 1998 Feb;31(2):350-5)