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The paper reports on some experimental results obtained from the production of ceramics containing steel slag and glass cullet from exhaust energy saving lamps mixed in different proportions. Blending of components was done by attrition milling. Pressed powders were fast fired (50 min, cold to cold) in air up to several temperatures in the range 1000-1140 degrees C. The sintering behaviour was studied by shrinkage and water absorption measurements. Density, strength and hardness of the fired bodies were determined and XRD were examined. The fired samples were finally tested in acidic environment in order to evaluate their elution behaviour and consequently their possible environmental compatibility. It is observed that the composition containing 60 wt.% of steel slag and 40 wt.% of glass cullet displayed the best overall behaviour.

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The paper describes results obtained in the development of a previous research. We study here, in fast firing, the sintering behaviour and measure some properties of tiles containing a mixture of 60 wt% of paper mill sludge and 40 wt% of glass cullet. The behaviour of this material is compared to those displayed by materials obtained by the same mixture added with 10, 20 and 30 wt% of a natural red clay. In parallel, the same properties are measured also on a reference blend, which is presently used to produce commercial tiles. We show that powders containing 60 wt% of paper sludge and 40 wt% of glass cullet to which 30 wt% of clay is added give rise to materials that display a stable sintering process and have good hardness and strength and therefore could be used for the industrial production of tiles.

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Three different types of paper mill sludge were first incinerated and then attrition milled separately or mixed with glass cullet in varying proportions to obtain powders of different compositions. These powders were then dried, sieved, uniaxially pressed into samples and air sintered. Fired samples were characterized by density, water absorption, shrinkage on firing, strength, hardness and fracture toughness measurements; SEM and X-ray diffractions were also carried out to investigate microstructure and phase composition. Some sintered samples displayed fairly good physical and mechanical properties as a consequence of their low residual porosity and fine microstructure.

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The prevalence of peptic ulcer disease was retrospectively analysed in 35 patients affected by primary hyperparathyroidism consecutively observed from 1977 through 1987. Eight of the examined patients (22.8%) had peptic ulcer (7 duodenal and 1 gastric ulcer), that in five cases (14%) represented the first clinical manifestation of the endocrine disease. A Zollinger-Ellison syndrome was demonstrated in three cases (8.5% of the total series, 37% of the patients with ulcer). There was no difference in calcium, gastrin and parathormone serum level between patients with and without ulcer, excluding patients with Zollinger-Ellison syndrome. These data confirm the high prevalence of peptic ulcer disease in hyperparathyroidism, but the mechanism causing this association remains to be elucidated.

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Calcitonin (CT), a 32-aminoacid peptide, is secreted by the parafollicular 'C' cells of the thyroid which derive from the ultimobranchial body and, ultimately, from the neural crest. In man, the main role of this hormone is to protect the skeleton during periods of physiological stress, such as growth, pregnancy and lactation by reducing calcium loss [1]. Nevertheless, some recent data, such as the finding of immunoreactive CT-like material (iCT) in the central nervous system [2] and in the cerebrospinal fluid and the demonstration of its analgesic action in rabbits [4] and in man [5] indicate a relationship between CT and the neuroendocrine system. The purpose of the present study is to evaluate the levels of CT in a group of addicts to heroin both before and during detoxication treatment with methadone or a non-opioid drug like clonidine.

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Identification of saliva on stamps or envelope flaps remains yet a not widely studied problem. In most forensic laboratories it is seldom carried out, but this fact does not reduce the importance of the assay. Most authors consider amylase a sufficiently specific marker of the presence of saliva; really, the only other human body fluid that contains high amounts of this enzyme is the pancreatic juice (and therefore feces). Here we present a simple and sensitive assay for the determination of alpha-amylase that uses a commercially available and well-known substrate. It is hydrolyzed by amylase with the production of soluble blue fragments, that can be measured by photometry, obtaining objective results. The presented assay identifies 1 X 10(-6) diluted saliva or that present on 0.5 mg of a stamp; 16-year-old samples can also be identified. Intra-assay and day-to-day CV resulted in 10.8% and 13.7%, respectively. Owing to the high sensitivity of the test, handling samples or reagents can introduce contamination with saliva traces, giving false-positive results. Addition of EDTA 0.1 mol/l to the incubation mixture, lowering the sensitivity to 1 X 10(-3) diluted saliva, overcomes this problem.

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