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AbstractPurpose:The aim of the study was to assess the exposure to Cobalt (Co) and Tungsten (W) in a group of hard metal tool sharpeners through a combined approach of air and biological monitoring, and to evaluate the effectiveness of a control and improvement intervention carried out in collaboration with the medical officers of the local Health Protection Agency, by biomonitoring.Methods:We enrolled 132 workers from 17 companies of the province of Brescia, northern Italy. The study was performed in two phases: (1) an environmental and biomonitoring survey to assess the workers’ exposure to Co and W at their usual working conditions; (2) a further biomonitoring survey 3 months after the enforcement of a control and improvement intervention, to assess its effectiveness.Results:Workers were found to be exposed to low concentration of airborne dust containing Co and W but after the intervention we recorded a significant decrease of the urinary concentrations of both Co and W. The extent of the decrease was correlated to the number of preventive industrial hygiene interventions that were carried out.Conclusions:Biological monitoring of Co and W in the hard metal tools manufacturing industry is a sensitive and effective method to evaluate the effectiveness of prevention practices.

Abstract

Background: The Lap-Band System� is the most common bariatric operation world-wide. Current selection criteria do not include patients with BMI ≤ 35. We report the Italian multicentre experience with BMI ≤ 35 kg/m2 over the last 5 years. Patients and Methods: Data were obtained from 27 centres involved in the Italian Collaborative Study Group for Lap-Band System�. Detailed information was collected on a specially created electronic data sheet (MS Access 2000) on patients operated in Italy since January 1996. Items regarding patients with BMI ≤ 35 were selected. Data were expressed as mean � SD except as otherwise indicated. Results: 225 (6.8%) out of 3,319 Lap-Band� patients were recruited from the data-base. 15 patients, previously submitted to another bariatric procedure (BIB =14; VBG= 1) were excluded. 210 patients were eligible for study (34M/176F, mean age 38.19�11.8, range 17-66 years, mean BMI 33.9�1.1, range 25.1-35 kg/m2, mean excess weight 29.5�7.1, range 8-41). 199 comorbidities were diagnosed preoperatively in 55/210 patients (26.2%). 1 patient (0.4%) (35 F) died 20 months postoperatively from sepsis following perforation of dilated gastric pouch. There were no conversions to laparotomy. Postoperative complications presented in 17/210 patients (8.1%). Follow-up was obtained at 6, 12, 24, 36, 48 and 60 months. At these time periods, mean BMI was 31.1�2.15, 29.7�2.19, 28.7�3.8, 26.7�4.3, 27.9�3.2, and 28.2�0.9 kg/m2 respectively. Co-morbidities completely resolved 1 year postoperatively in 49/55 patients (89.1%). At 60 months follow-up, only 1 patient (0.4%) has a BMI >30. Conclusions: Although surgical indications for BMI ≤ 35 remain questionable, the Lap-Band� in this study demonstrated that all but 1 patient achieved normal weight, and most lost their co-morbidities with a very low mortality rate.

Purpose Subcutaneous Infusion Ports (SIPs) for prolonged venous access are useful tools for drug administration in a wide range of chronic diseases. An extensive use of these devices has to be balanced against the potential complications worsening the length and the quality of life of frequently compromised patients. The aim of the present study is the prospective evaluation of early and late complications of the technique for the blind placement of totally implantable devices for prolonged venous access.Methods Between April 1, 1991 and September 30, 1999, 980 SIPs were implanted in 967 patients. Thirteen patients received 2 SIPs. The surgical procedure, the catheter through peel-away technique after infraclavicular approach to the right or left subclavian vein, was performed without intraoperative fluoroscopy (blind placement technique) in the operating room under local anaesthesia. A postoperative chest radiography to rule out any procedure-related complications and to check the position of the catheter tip was obtained in all cases. For the purpose of the study, intraoperative complications as well as all SIP-related complications were recorded during the follow-up period and classified as major and minor complications.Results The study population consisted of 524 males/443 females, with a mean age of 56.3 ± 11.4 years (range 19–85 years). Primary diagnosis was malignancy in 916 patients (94.7%), acquired immunodeficiency syndrome (AIDS) in 44 patients (4.5%), and short gut syndrome secondary to subtotal small bowel resection in 2 cases (0.2%), others in 5 cases (0.5%). Perioperative complications were recorded in 12.9% of the 980 insertion procedures, including 77 cases of arterial puncture (7.8%) of the subclavian artery, 1 case of hemoptysis (without clinical and radiological evidence of pneumothorax) (0.1%), 23 cases of pneumothorax (2.3%), 20 of which (86.9%) required chest drainage, 10 cases of unsuccessful progression of the J-wire after the venepuncture (1%), 16 cases of catheter malposition (1.6%). As for the follow-up, 919 patients (95.0%) who had received 942 SIPs turned out to be suitable for long-term analysis, while 48 patients (5.0%) were excluded due to missing data. Seventy-seven SIPs (8.2%) were removed during the follow-up period, 13 of which received a second SIP. Long-term complications were recorded in 9.5% of the 942 SIPs, including mechanical complications (2.9%), infections (4.4%) and venous thrombosis (1.2%). Minor and major complication rates were 7.3% and 2.2% respectively. The overall incidence of SIP-related complications was 22.1%, including 44 major complications (4.5%) and 173 minor complications (17.6%).Conclusions Given the low rate of major complications, SIPs should be considered safe and effective devices, representing the first choice approach for prolonged venous access. Blind placement technique performed by full-trained operators yields adequate success rate to be suggested as a routine procedure.

The paper investigated, by means of thermal analysis measurements, the validity of three different methods for the evaluation of the activation energy of crystallization for surface nucleated glasses belonging to the MgO-CaO-Al2O3-SiO2 system, separating anorthite and diopside crystals. The values obtained from Kissinger equation of the activation energy for crystallization are comparable with those obtained by other authors for similar glassy systems, 90 to 150 kcal/mol. The results of the kinetic analysis using single-crystallization-peak method should be corrected taking into account the dimensionality of crystal growth.

Anorthite and diopside have been obtained from complete devitrification of glasses belonging to the quaternary system MgO-CaO-Al2O3-SiO2. Microstructure, the natural trend of the nucleation mechanism and kinetic studies on the crystallization phenomenon have been investigated by means of optical and electron microscopies, thermal and thermomechanical techniques and X-ray powder diffractometry. All the glasses investigated show a complete crystallization starting from a simple surface nucleation process. The activation energy for the crystallization process proved to be higher than that for viscous flow, leading to an important aspect modification in the sample during ceramization. Thermal stability and physical properties of both glass and glass-ceramic materials have been tested, suggesting the possible use of these materials in industrial application.

Mold powders, initially fly ash based, were introduced about 40 years ago in the steel continuous casting process. Nowadays, also synthetic powders consisting of mixtures of various minerals are used. The aims of the powders, when added to the free surface of the liquid steel in the mold, can be summarized as follows: thermal isolation of the steel surface, in order to prevent its solidification; protection of the steel surface from the oxidation; lubrication and heat transfer control between the mold wall and the solid steel shell; absorption of non-metallic inclusions coming from the steel. The purpose of this work is to characterize the thermal behavior of some mold powders for continuous casting when they are subjected to different heating cycles: heating rate of 30degC/min up to the sample fusion; heating rate of 80degC/min up to the sample fusion; instantaneous or "flash" heating, which allows to heat the sample in few seconds. On the basis of predetermined time or temperature intervals applied, this study yielded to different results, like the melting temperature, the presence of crystallizations, and the phenomena that occur in the material.