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Spent sulfite liquor is a lignocellulosic waste obtained after the sulfite pulping process. It is mainly formed by sugars and lignosulfonates which are isolated from the pulp during the cooking process. The current work investigates the kinetic modeling of the sulfite process from a biorefinery point of view since monosaccharides present in the spent liquor can be used as a raw material in further biorefinery processes to produce other value-added products. Kinetic parameters of carbohydrate degradation have been determined following sugar and inhibitors from wood to spent liquor, using laboratory scale reactors and different temperatures, 130, 140 and 150 °C. Three types of reaction schemes were developed. Kinetic parameters were obtained for each one using first and n order reactions, using Aspen Custom Modeler. Results show that the best temperature to be used in the process is 130 °C, giving the maximum sugar conversion, 33.91 mol% and obtaining 13.81 mol% of decomposition products.

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The application of solvent-based paints by spraying in paint booths is extensively used in a wide range of industrial activities for the surface treatment of a vast array of products. The wastes generated as overspray represent an important environmental and managerial problem mainly due to the hazardous characteristics of the organic solvent, rendering it necessary to appropriately manage this waste. In this paper a solidification/stabilization (S/S) process based on accelerated carbonation was investigated as an immobilization pre-treatment prior to the disposal, via landfill, of an alkyd solvent-based paint waste coming from the automotive industry; the purpose of this S/S process was to immobilize the contaminants and reduce their release into the environment. Different formulations of paint waste with lime, lime-coal fly-ash and lime-Portland cement were carbonated to study the effect of the water/solid ratio and carbonation time on the characteristics of the final product. To assess the efficiency of the studied S/S process, metals, anions and dissolved organic carbon (DOC) were analyzed in the leachates obtained from a battery of compliance and characterization leaching tests. Regarding the carbonation of paint waste-lime formulations, a mathematical expression has been proposed to predict the results of the leachability of DOC from carbonated mixtures working at water/solid ratios from 0.2 to 0.6. However, lower DOC concentrations in leachates (400mg/kg DOC in L/S=10 batch leaching test) were obtained when carbonation of paint waste-lime-fly-ash mixtures was used at 10h carbonation and water to solid ratio of 0.2. The flammability characteristics, the total contents of contaminants and the contaminant release rate in compliance leaching tests provide evidence for a final product suitable for deposition in non-hazardous landfills. The characterization of this carbonated sample using a dynamic column leaching test shows a high stabilization of metals, partial immobilization of Cl(-), SO(4)(2-), F(-) and limited retention of DOC. However, the obtained results improve the previous findings obtained after the paint waste S/S using uncarbonated formulations and would be a useful pre-treatment technique of the alkyd paint waste prior to its disposal in a landfill.

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An environmental problem of the foundry activities is the management of industrial waste generated in different processes. The foundry sludge from gas wet cleaning treatment that contains organic and inorganic compounds and a high content of water is an interesting example. Due to their characteristics, they can be managed using different stabilisation/solidification (S/S) technologies prior to land disposal. The purpose of this work is to study S/S formulations in order to improve the control of the mobility of the pollutants and the ecotoxicity of the samples. Different mixtures of cement or lime as binders and additives (foundry sand, silica fume, sodium silicate, silicic acid, activated carbon and black carbon) have been used in order to reduce the mobility of the chemical and ecotoxicological regulated parameters and to compare the results for commercial and residual additives. The best results have been obtained with sorbents (activated carbon and black carbon) or sodium silicate. The results of the foundry sand ash as additive can conclude that it can be used as replacement in the cement products. However, silica fume in the samples with lime and siliceous resin sand as additives gives products that do not fulfil the regulated limits. Finally, some linear expressions between the chemical parameters and the quantity of material used in the samples have been obtained.

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The use of Vibrio fischeri as luminescence bacteria is particularly effective in evaluating contaminated sediment. In this study, the ecotoxicity of five core sediments from the Bay of Santander, northern Spain, utilising V. fischeri as marine bacterium, was carried out. Different toxicity assay procedures were applied in order to study the influence of the mobility and bioavailability of the pollutants. Basic Solid Phase Test (BSPT) in whole sediment and acute toxicity test, using pore water and three leaching test procedures as liquid extracts, were applied. In addition, the study of the influence of the pH value on the toxicity results of the leaching tests was conducted. The obtained results show toxicity units (TU50) values in BSPT test ranging from 0.42 to 39.06 with a decrease with depth as general trend and TU50 values from 0.010 to 0.389 in the liquid extracts, where TU50 is calculated as the inverse of EC50 (%). The obtained data show the historical toxicity trends of the Bay of Santander and provides a technical database for the management of contaminated sediments. Moreover, these results showed evidence that each sediment test procedure provided independent and complementary ecotoxicological responses useful for a sediment classification. In order to analyse the correlations between chemical parameters (both organic and inorganic) and the toxicity results, the self-organising map (SOM) neural network and regression equations were applied. Satisfactory correlations (R=0.93) between chemical concentrations of sum of five heavy metals and 16 PAHs and BSPT toxicity were obtained.

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The accumulation rates, the geochronology of metals and PAH contamination, and the Microtox toxicity are studied in five sediment cores (50 cm length) covering different areas of the Santander Bay, Northern Spain. Chronology given by (210)Pb and (137)Cs reveals significant differences in accumulation rates between sites (0.2-1.1 cm/year), as well as a variable degree of anthropogenic enrichment factors for Fe, Mn, Cu, Pb, Zn, Ni (from 1 to 15) and concentrations of summation Sigma 16PAHs (from 0.01 to 23.84 mg/kg dw) in sediments over the last 90 years. The results indicate the increasing contamination pressure from industrial and urban activities along the Bay. No toxic results from the Microtox test are obtained either with pore water or with normalised sediment aqueous extracts (European Norm EN 12457), suggesting low water solubility and low availability of contaminants in the studied sediments. However, the EC50 values from the Microtox Basic Solid Phase Test (BSPT) ranged from 0.03% to 2.35%, showing vertical toxicity profiles in accordance with metal and PAHs behaviour. The correlation degrees of Microtox BSPT toxicity to chemical concentration in sediment profiles are widely variable showing a high site-dependent toxicity. The oligochaete Limnodrilus hoffmeisteri has been used as a chronic bioassay over surface sediments of two of the studied sites, showing results coherent with the Microtox BSPT acute test results. Global results of the present work provide regional geochemical baselines for metals and PAHs and toxicological data now make it possible to obtain a preliminary quality assessment of the Santander Bay sediment profiles.

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Since Ellmann's description in 1948 numerous authors have studied the respiratory manifestations associated with rheumatoid arthritis. Amongst the numerous disorders described, dilatation of the bronchi, although one of the most frequent, remains largely under-estimated. The authors report a series of 21 patients presenting jointly with both rheumatoid arthritis and bronchiectasis which was documented using thoracic computed scanning. All the subjects were female. For 20 of these patients, the appearance of bronchial suppuration preceded that of the articular manifestations by several years. Bronchial dilatation in these cases can, only with difficulty, be considered as a complication of arthritis as has been previously suggested. Rather it appears as a possible pre-disposing factor in the occurrence of the rheumatoid disease. These hypotheses explain the pathophysiological mechanisms implicated in this association are discussed.

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The main respiratory manifestations of amylosis are tracheobronchial involvement and modular or diffuse parenchymal disease. Amyloid deposits in the pleura are exceptional. We observed transsudative pleural effusion and heart failure in a patient with multiple myeloma, leading to the discovery of pleural amylosis. Amyloid deposits in the pleura may be fortuitous discoveries since pleural effusion is not necessarily observed. It is however important to be aware of this possibility since the localization is easily accessible for diagnosis. Specific stains are effective diagnostic tools even for transsudative effusions, particularly in suggestive clinical conditions such as multiple myeloma.

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The authors report two cases of myelomatosis localised to the pleura, one of which was associated with an adenocarcinoma. Pleural effusions are relatively rare during the course of multiple myeloma and most often occur with non-specific disorders of the disease. The myelomatous origin of a pleural effusion can only be made by analysis of the pleural fluid and should be recognised early enough to enable aggressive treatment to be instituted even if the prognosis associated with such a localisation is very poor.

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The authors report a case of pleural fibroma discovered during an examination for thoracic pains in a 65 year old woman. Histochemical studies were positive with vimentin and negative with KL1 antibodies and compatible with the most recent hypotheses concerning the purely fibroblastic origin of these tumours.

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We report a fatal case of acute interstitial pneumonitis in a patient treated with carmustine (BCNU) for a brain tumor. Bronchoalveolar lavage (BAL) revealed lymphocyte alveolitis with a low CD4/CD8 ratio (0.36), consistent with an immunoallergic phenomenon, rather than the most often evoked toxic hypothesis.

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The authors report a case of pulmonary blastoma, a rare type of pulmonary malignant tumour. The patient was treated by pneumonectomy combined with chemotherapy and radiotherapy. The outcome was favourable, and during an 11-year follow-up there was no sign of recurrence.

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The authors report two cases of thoracic actinomycosis with contrasting presentations, just as the diagnosis was obtained by different tests underlying the varied aspects of this disease. Indeed this infectious pathology does infrequently mimic tuberculosis or lung cancer with similar clinical and radiological appearances. The particular characteristic of the bacteriological culture and the quasi specific character of the pale, yellow grains on histology are recalled, as well as the different treatments necessary to ensure a cure in 90% of cases.

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The authors report about one case of respiratory distress occurring after pleural talcage for pneumothorax. Although few cases have been published, this complication is known, and it should lead to carefully consider the indication of this technique and to limit the total amount of talc used.

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Infections caused by Mycobacterium chelonei are rare. We report a case of pulmonary infection in a 57-year-old non-immunocompromised woman. Most of the abnormalities were observed at radiology which showed bilateral apical excavated opacities. The disease could only be diagnosed on surgical biopsies. Beside diagnostic problems, M. chelonei infections are a source of therapeutic problems.

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In this article the authors start by going over the anatomical and neuro-physiological pathways of transmission of painful nerve impulses from the periphery to the centres. Pain is a "sensation" which is integrated in both a psychological and an emotional context. Psycho-physiological studies show that the cortex of the brain therefore plays a basic role in this integration and this allows us to consider the psycho-prophylaxis of delivery. Certain failures of psychoprophylaxis demonstrate the role of cultural factors and of factors that are specific to the subject of the pain of labour. The latter are dominated by anxiety, wich is at the same time due to the circumstances of the labour and of the individual patient. The latter stem from several sources: fear of death, separation, guilt and castration. There is one more psychological element that seems to be equally important and that is, morbid narcissism. The obstetrician should fight against the patient's anxieties which will thwart his work and disturb the onward progress of the labour. He will usually succeed but not always by the pathways that he thinks he is taking.

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