1,066 research outputs found

    Le péroxyde d'hydrogÚne en désodorisation physico-chimique : RÎle de la composition de la solution de lavage dans le mécanisme d'action

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    La dĂ©sodorisation physico-chimique en stations d'Ă©puration s'effectue gĂ©nĂ©ralement par lavage basique oxydant pour piĂ©ger les espĂšces soufrĂ©es rĂ©duites telles que H2 S ou CH3 SH. L'utilisation du peroxyde d'hydrogĂšne n'est pas encore rĂ©pandue en comparaison de celle du chlore. Cette Ă©tude a Ă©tĂ© menĂ©e afin de dĂ©terminer le comportement de H2O2 en fonction de la composition de l'eau de lavage. L'influence des paramĂštres : concentration en mĂ©taux (fer, manganĂšse, cuivre et zinc), pH, [H2O2], [CO32-], [HS-] a Ă©tĂ© Ă©tudiĂ©e en utilisant un plan d'expĂ©riences. La dĂ©composition de H2O2 et la concentration de radicaux libres ont Ă©tĂ© mesurĂ©es pour chaque expĂ©rience. En prĂ©sence de mĂ©taux, un pH Ă©levĂ© et une forte concentration en peroxyde sont les deux paramĂštres principalement responsables d'une forte dĂ©composition. Cette dĂ©composition serait accompagnĂ©e d'une production de radicaux avec [HO°]max =10-13 M. Cette valeur mesurĂ©e de radicaux dans le milieu n'explique qu'une petite part de la dĂ©composition de peroxyde observĂ©e. Par consĂ©quent, la majoritĂ© de la dĂ©composition est due Ă  des rĂ©actions soit Ă  la surface des oxydes, soit en solution avec les cations dissous. Le mĂ©lange de mĂ©taux et de carbonates Ă  pH 10,5 prĂ©sente un effet de synergie sur la dĂ©composition de H2O2. Ces rĂ©sultats dĂ©montrent que malgrĂ© le pouvoir oxydant des radicaux HO° formĂ©s, l'utilisation de H2O2 en dĂ©sodorisation ne sera possible qu'avec l'ajout de stabilisant.Deodorization of wastewater treatment plants involves the elimination of molecules such as NH3, amines and sulphur compounds like H2 S and mercaptans. In classical physico-chemical processes, NH3 and amines are trapped in acid solution by washing air in a scrubbing tower, while sulphides are eliminated in basic oxidising solutions. The oxidant usually used is sodium hypochlorite. Elimination of sulphides and organosulphides generally demands two scrubbers: one at pH 9 and the other at pH 11. Because chlorine in deodorization generates the formation of organochlorinated species, it should soon become necessary to replace this oxidant in order to avoid the formation of such compounds. The present study follows the behaviour in wash conditions not of chlorine, but hydrogen peroxide, in order to discover the deodorization capacity of this molecule.The kinetics of H2 S oxidation by H2O2 are well known; the constant is given by log k = 12.04 - (2641/T) - 0.186 x pH (Millero et al., 1989). Unfortunately H2O2 shows strong decomposition in alkaline medium, due to the presence of metals and carbonates in the solution. Initiating a homolytic reaction results in the decomposition of peroxide. However, increasing the concentration of free radicals may improve H2 S oxidation and consequently, the efficiency of the process.To better understand the behaviour of H2O2 in wash conditions, various parameters were studied, namely pH (9 and 10.5), [H2O2] (1 and 5 g L-1), metal concentrations (iron, manganese, copper and zinc) (20 and 200 ”g L-1), [CO32-] (0 and 100 mg L-1) and [HS-] (0 and 2 mg L-1). Four experimental designs, one for each metal, were employed to reduce the number of experiments and benefit from statistical laws. H2O2 decomposition and HO° concentration were measured and empirical equations established. All experiments were performed in closed-batch reactors with ultra-pure reactants and water. Measurements of HO° concentrations necessitated the addition of atrazine to the solution. The oxidation of this pesticide by HO° is well known. Using atrazine concentrations measured through time, the HO° concentrations were calculated according to the equationln ([Atz]0/[Atz]) = k[HO∘]twith k=2.1 × 109 M-1 s-1 (De Laat et al., 1997). Oxidation of atrazine was halted by extraction onto a Ct18 Sep-Pack resin and samples were analysed by liquid chromatography.The results showed that in the presence of metals H2O2 decomposition was maximal at high pH and with high peroxide concentrations. The decomposition was accompanied by HO° production. However, the presence of metals generated the decomposition of H2O2 with a reduced production of free radicals compared with ultra-pure water, which indicates that metal oxides were not only decomposition catalysts, but also radical inhibitors. Comparison of simplified radical decomposition, calculated according to the equation([H2O2]/[H2O2]0)=e-k[HO∘]t,and observed decomposition showed that under these conditions H2O2 consumption was mainly due to metal reactivity. Nonetheless, increasing iron and copper concentrations from 20 to 200 ”g L-1 did not modify the decomposition rate of H2O2. For this reason we postulate a Fenton-like reaction between H2O2 and dissolved metals in which concentrations are determined by solubility products. It follows that the kinetics of H2O2 decomposition can be summarised by r=-k1 [oxide][H2O2] - k2[ Mn+][H2O2] - k3 [HO°][H2O2], with [metal]Tot =[Mn+] + [oxide] and, in the case of Cu and Fe, k1 [oxide][H2O2] << k2[ Mn+][H2O2].To conclude, the addition of four metals with [CO32-]=1 g L-1 at pH 10.5 produces a synergetic effect, resulting in a much faster decomposition. These conditions, unfortunately, resemble deodorization conditions. The use of a stabiliser that inhibits not only free radicals but also decomposition catalysts is therefore necessary for deodorization

    Étude du traitement et du recyclage des eaux issues des serres horticoles

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    La gestion de l'eau dans les systĂšmes de culture hors-sol fait apparaĂźtre deux problĂšmes distincts. D'une part, les ressources en eau doivent ĂȘtre de bonne qualitĂ© et ne pas contenir de pesticides ou de germes pathogĂšnes. D'autre part, les rejets fortement " chargĂ©s " en nutriments (NO3-, PO43-) polluants pour l'environnement, doivent ĂȘtre limitĂ©s par le biais de leur recyclage ce qui implique nĂ©cessairement la dĂ©sinfection des effluents.La technique mise en Ɠuvre pour obtenir cette maĂźtrise de la qualitĂ© tant chimique que microbiologique des solutions circulantes en culture hors-sol est celle d'une oxydation Ă  l'ozone seul et couplĂ© au peroxyde d'hydrogĂšne dans des rĂ©acteurs constituĂ©s de mĂ©langeurs statiques. Les conditions de traitement sont une dose d'oxydant de 10 g O3/m3 d'effluent Ă  traiter, un rapport H2O2/O3 de 0,15 g/g pour un temps de contact dans le rĂ©acteur de l'ordre de la seconde. EtudiĂ© sur site dans le cadre du traitement de effluents de serre rĂ©els, le procĂ©dĂ© s'est rĂ©vĂ©lĂ© tout Ă  fait adaptĂ© pour abattre les pesticides (# 90 % pour l'atrazine), maĂźtriser la prolifĂ©ration des micro-organismes (Flore aĂ©robie mĂ©sophile, flore fongique) et en particulier des germes pathogĂšnes (Clavibacter michiganensis, Fusarium, Pythium sp ).Le procĂ©dĂ© novateur O3/H2O2 sur mĂ©langeurs statiques constitue donc pour les serristes une rĂ©ponse nouvelle dont l'un des intĂ©rĂȘts est de combiner les effets " dĂ©toxiquant " et dĂ©sinfectant.The management of water resources in soil-less cultures presents two difficulties. On one hand, the quality of these resources has to be good, that is to say without pesticides or pathogens. On the other hand, the effluents contain high concentrations of nutrients (NO3-, PO43-), damageable for the environment, and should be recycled. Thus, recycling has to include necessarily a disinfection step to satisfy the quality requirement. The main disinfection treatments used in soil-less cultures are slow sand filtration, ultraviolet treatment, heat treatment, nanofiltration, ozone or hydrogen peroxide oxidation, iodine or chlorine treatment.In order to control the chemical as well as the microbiological quality of the recycled nutrient solution, we suggest oxidation (O3) and advanced oxidation (O3/H2O2) processes, carried out in static mixers as chemical reactors instead of bubble columns. We have been studying this process in situ for the treatment of a 1-hectare greenhouse. The pilot plant unit can be configured under three setups (Figure 2) according to the aim to favor either the molecular action of ozone or the formation of very reactive radical species such as the hydroxyl radical. In this second case, the mechanism of ozone decomposition is given by Figure 1.The first step of the study was to measure the influence of the nutrient solution to be recycled on the efficiency of atrazine removal (Figures 3 and 4). In comparison with tap water, the percentage of pesticide removal is lower by about 10 to 20 %. Solutions with nutrients do not drastically change the process efficiency. The experiments were carried out with various ozone dosages and various ozone / hydrogen peroxide mass ratios, using the three configurations (Figures 5 and 6). With these results, the best operating conditions for micropollutant removal are a treatment rate of about 10 g O3 /m3 of treated solution, a H2O2/O3 ratio equal to 0.15 g/g and a contact time in the reactor in the range of 1 to 2 seconds. The influence of the configuration type is not really marked. The results show that, under these conditions, this technique leads to good pesticide removal efficiencies (about 90 % for atrazine).In a second step, experiments were carried out on real solutions containing microorganisms from the greenhouse, sometimes spiked with special bacteria (Clavibacter) or fungi (Fusarium). Some results are reported in Figures 7, 8 and 9. With the same oxidant dosage conditions, the role of the configuration is clearly demonstrated. The best results are obtained with a molecular action of ozone in the first static mixed reactor followed by a free-radical action within the second reactor. Thus, it is possible to prevent germ proliferation (aerobic mesophilic flora and fungi flora) and particularly pathogenic species. The abatement of Clavibacter michiganensis reaches 3.5 to 4 logarithmic units, 1 to 1.5 units for Pythium and 2 to 4 units for Fusarium. The treatment does not effect a complete sterilization, e.g., the beneficial bacterium Pseudomonas fluorescens survives. The global impact of the treatment on the nutritive quality of the treated solution is negligible. Nevertheless, we can note that the process induces a decrease of the ion concentrations of Fe (II) (- 5 to 30 %) and Mn (II) (-10 to 15 %) as a result of the oxidation of the EDTA chelate. In fact, this problem is observed with all oxidation and UV treatments. The residual oxidant (O3, H2O2) concentrations are low and do not induce obvious toxic effects on the cultures.Thus, the technique is consistent with a recycling of the treated effluents. The advantages of the process include very short contact times, compactness of the equipment, no need for pretreatment, reasonable investment and operating costs, an increase of the oxygen concentration in the treated effluent, and possible curative effects on the culture's germ contamination due to the residual concentration of hydrogen peroxide. The disinfection efficiency of this suggested process is similar to those obtained with more common techniques like UV irradiation. Moreover, the studied process can also reduce, for example, an eventual chemical pollution of the water resource. In conclusion, the O3, H2O2 process in static mixers appears to be a new solution for greenhouse farmers

    Étude de la production des ions bromate lors de l'ozonation des eaux de la Banlieue de Paris : choix du mode d'ozonation et variation des param tres physico-chimiques

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    Cette Ă©tude a permis d'Ă©valuer l'importance de la concentration en ions bromure, de la tempĂ©rature et de la nature de la MatiĂšre Organique Naturelle (MON) sur la production des ions bromate en s'appuyant sur des expĂ©riences conduites en laboratoire et sur pilote semi-industriel (Centre d'Essais de MĂ©ry-sur-Oise).Trois campagnes d'ozonation effectuĂ©es en parallĂšle Ă  MĂ©ry-sur-Oise et au LCEE (Laboratoire de Chimie de l'Eau et de l'Environnement) sur des eaux filtrĂ©es sable, ont montrĂ© que les expĂ©riences conduites en laboratoire et sur pilote semi-industriel mĂšnent Ă  des rĂ©sultats similaires, soit une relation linĂ©aire [BrO3-]=f (C∙τ) vĂ©rifiant une pente identique pour des conditions expĂ©rimentales donnĂ©es (teneur en ions bromure, tempĂ©rature, origine de l'eau). Ces travaux ont montrĂ© de façon nouvelle qu'une faible variation de la concentration en ions bromure (± 15 Ă  20 ”g.L-1) suffisait Ă  modifier significativement la formation des ions bromate. A C∙τ=10 et T=21°C, la production des ions bromate est passĂ©e de 16 Ă  27 ”g.L-1 pour une augmentation de la concentration en ions bromure de 80 Ă  95 ”g.L-1. Les rĂ©sultats obtenus ont montrĂ© de plus que la tempĂ©rature est un facteur important puisqu'une diffĂ©rence de 8°C (13 Ă  21°C) a entraĂźnĂ©, pour la mĂȘme eau (80 ”g.L-1 d'ions bromure, C∙τ=10), une augmentation de la concentration en ions bromate de 10 Ă  16 ”g.L-1. Pour d'autres eaux (Seine, Marne et Oise), trois autres campagnes conduites avec des eaux clarifiĂ©es ont Ă©tĂ© effectuĂ©es aprĂšs ajustement de la teneur en ions bromure et rĂ©gulation de la tempĂ©rature, ces trois eaux prĂ©sentant par ailleurs des caractĂ©ristiques similaires en ce qui concerne le pH et l'alcalinitĂ©. A C∙τ Ă©quivalent, la production d'ions bromate s'est avĂ©rĂ©e significativement plus faible pour l'eau de l'Oise que pour les deux autres eaux. La nature de la MON pourrait donc avoir une influence notable sur la formation des ions bromate.The publication of Kurokawa et al. in 1990 confirming the toxicity of bromate of rats and mice, initiated the research effort that was internationally conducted during the last seven years to better understand the reaction mechanisms of bromate formation during the ozonation of natural waters. Based on the research findings regarding the effect of a number of parameters (bromide, ozone dose, pH, temperature, alkalinity, DOC content, ammonia, ...), predictive models (empirical and reaction kinetic based models), including molecular and/or radical pathways, have been developed with more or less success. Complementary results are still needed to better understand this complex mechanism.The main objective of our work was to evaluate how the seasonal variation of the physical chemical characteristics of Paris-area source waters (i.e. bromide content, temperature, natural organic matter) can affect the production of bromate during ozonation. In order to confirm that lab-scale experiments could be proposed to develop such research program, parallel tests were first conducted at the bench- and pilot-scale based on comparable C∙τ conditions. The lab-scale reactor was a 380 ml glass column (internal diameter: 0.02 m; height: 1.2 m) equipped with a water jacket to allow temperature to be varied and maintained. These reactor was used as a continuous flow reactor with recirculation. The pilot-scale ozonation contactor installed at the MĂ©ry sur Oise water treatment plant was comprised of four 30-liter columns in series (diameter: 0.1m ; height: 4m). The first column is used as the application column while the three others are used as residence column. The results have shown that lab-scale ozonation experiments conducted on MĂ©ry sur Oise sand filtered water led to similar results compared to pilot ozonation conducted on the same water and at the same temperature (sampled the same day) using the MĂ©ry sur Oise pilot-scale reactor. For applied C∙τ that ranged from 4 to 20 mg O3/L.min, similar linear relationship between bromate formation and applied C∙τ was obtained with the two reactors.A survey conducted on the Oise River has shown that the bromide concentration ranged from 40 ”g/L (winter period) to 80 ”g/L (summer period). If it is already well known that higher the bromide content, higher the bromate formation, our work has also pointed out that even a small increase of the bromide concentration from 80 to 95 ”g/L (15 ”g/L of bromide spiked as KBr) can significantly impact the bromate formation (same experimental conditions) that, as an example, increased from 16 to 27 ”g/L for C.t of 10 at 21 °C.The temperature of the Oise river can vary from 5 °C up to 25 °C. Using carefully controlled temperature conditions, one can observed that the slope of the bromate production versus applied C∙τ increased with increasing temperature (same water). For example, the production of bromate during the ozonation (applied C∙τ=10) of the MĂ©ry sur Oise sand filtered water was 7, 10 and 16 ”g/L for 5, 13 and 21 °C, respectively. Complementary experiments, have shown that the impact of the variation of the initial bromide concentration was proportionally more important for low-temperature water (5 to 13 °C) than for moderate-temperature water (20 °C).The origin and nature of the water is considered to play a significant role on the formation of bromate during ozonation, however few studies have evaluated the importance of these parameters using carefully controlled experimental conditions. In order to better define how important is the change in bromate production with the modification of the quality of the Paris suburbs water sources, especially the organic content (nature and concentration of the NOM), two sets of experiments were conducted.In the first part of the work, the MĂ©ry sur Oise sand filtered water was sampled at three different periods of the year 1996 (June, July and December), and the ozonation experiments were conducted at the same temperature (21 °C) after bromide concentration was adjust to 80 ”g/L. The three water samples had the same pH and did not contain ammonia. Significant differences were observed in the bromate production, showing a larger production with the winter water as compared to the summer water. The fact that the winter water was enriched in DOC (3.7 mg/L of DOC) as compared to the two others (2.6 - 2.7 mg/L of DOC) may explain this difference since a larger ozone dose was probably necessary (ozone transfert not controlled because of the small size of the lab-scale reactor) to reach the same applied C∙τ due to a higher ozone consumption from the natural organic matter. The slightly lower alkalinity of the winter sample (200 mg/L as CaCO3 as compared to 250 mg/L CaCO3 for the summer samples) could have led to a less pronounced scavenger effect, condition that favors the radical pathway which is generally predominant. However, it is also known that carbonate species can also promote the formation of bromate due to the production of carbonate radicals. Comparing the results obtained with the water samples collected during the summer period, more bromate was produced in July than in June. The higher hydrophobic character (more aromatic in character) of the NOM of the water sampled in July (SUVA=2.15) as compared to the June sample (SUVA=1.88), characteristic that favor the ozone consumption and consequently the OH radical production, may justify this finding.In the second part of the work, the bromate formation obtained during the ozonation of the three major water sources of the Paris suburbs (sampled after clarification), Oise River, Marne River and Seine River, was compared (same temperature) after the bromide content was adjust to 80 ”g/L. Similar results were obtained with the clarified Marne river and Seine River, the two waters showing the same physical chemical characteristics (2.2 and 2.5 mg/L of DOC; pH 7.9 and 7.8; Alkalinity: 225 and 210 mg/L as CaCO3). A lower production of bromate as a function of the applied C∙τ was observed with the clarified Oise river, result that is in contradiction with our previous hypotheses since this water source showed the highest DOC content, the highest SUVA and the lowest alkalinity among the three waters studied.More work needs to be done to better understand the impact of the origin and nature of the NOM on the bromate formation mechanisms. As a general conclusion, this work also confirmed that the physical chemical characteristics of source water (DOC, temperature, alkalinity, bromide content,
) are more important factors as compared to the hydraulic characteristics of the reactor.Keywords

    Tracking marine mammals in 3D using electronic tag data

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    1. Information about at-depth behaviour of marine mammals is fundamental yet very hard to obtain from direct visual observation. Animal-borne multisensor electronic tags provide a unique window of observation into such behaviours. 2. Electronic tag sensors allow the estimation of the animal's 3-dimensional (3D) orientation, depth and speed. Using tag flow noise level to provide an estimate of animal speed, we extend existing approaches of 3D track reconstruction by allowing the direction of movement to differ from that of the animal's longitudinal axis. 3. Data are processed by a hierarchical Bayesian model that allows processing of multisource data, accounting for measurement errors and testing hypotheses about animal movement by comparing models. 4. We illustrate the approach by reconstructing the 3D track of a 52-min deep dive of a Blainville's beaked whale Mesoplodon densirostris adult male fit with a digital tag (DTAG) in the Bahamas. At depth, the whale alternated regular movements at large speed (>1·5 m s-1) and more complex movements at lower speed (<1·5 m s-1) with diïŹ€erences between movement and longitudinal axis directions of up to 28°. The reconstructed 3D track agrees closely with independent acoustic-based localizations. 5. The approach is potentially applicable to study the underwater behaviour (e.g. response to anthropogenic disturbances) of a wide variety of species of marine mammals ïŹtted with triaxial magnetometer and accelerometer tags.PostprintPeer reviewe

    Relativistic and retardation effects in the two--photon ionization of hydrogen--like ions

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    The non-resonant two-photon ionization of hydrogen-like ions is studied in second-order perturbation theory, based on the Dirac equation. To carry out the summation over the complete Coulomb spectrum, a Green function approach has been applied to the computation of the ionization cross sections. Exact second-order relativistic cross sections are compared with data as obtained from a relativistic long-wavelength approximation as well as from the scaling of non-relativistic results. For high-Z ions, the relativistic wavefunction contraction may lower the two-photon ionization cross sections by a factor of two or more, while retardation effects appear less pronounced but still give rise to non-negligible contributions.Comment: 6 pages, 2 figure

    Effects of Cr/Ni ratio on physical properties of Cr–Mn–Fe–Co–Ni high-entropy alloys

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    Physical properties of ten single-phase FCC CrxMn20Fe20Co20Ni40-x high-entropy alloys (HEAs) were investigated for 0 ≀ x ≀ 26 at%. The lattice parameters of these alloys were nearly independent of composition while solidus temperatures increased linearly by ∌30 K as x increased from 0 to 26 at.%. For x ≄ 10 at.%, the alloys are not ferromagnetic between 100 and 673 K and the temperature dependencies of their coefficients of thermal expansion and elastic moduli are independent of composition. Magnetic transitions and associated magnetostriction were detected below ∌200 K and ∌440 K in Cr5Mn20Fe20Co20Ni35 and Mn20Fe20Co20Ni40, respectively. These composition and temperature dependencies could be qualitatively reproduced by ab initio simulations that took into account a ferrimagnetic ↔ paramagnetic transition. Transmission electron microscopy revealed that plastic deformation occurs initially by the glide of perfect dislocations dissociated into Shockley partials on {111} planes. From their separations, the stacking fault energy (SFE) was determined, which decreases linearly from 69 to 23 mJ·m−2 as x increases from 14 to 26 at.%. Ab initio simulations were performed to calculate stable and unstable SFEs and estimate the partial separation distances using the Peierls-Nabarro model. While the compositional trends were reasonably well reproduced, the calculated intrinsic SFEs were systematically lower than the experimental ones. Our ab initio simulations show that, individually, atomic relaxations, finite temperatures, and magnetism strongly increase the intrinsic SFE. If these factors can be simultaneously included in future computations, calculated SFEs will likely better match experimentally determined SFEs

    p53 status correlates with histopathological response in patients with soft tissue sarcomas treated using isolated limb perfusion with TNF-α and melphalan

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    Background: Recombinant tumor necrosis factor-α (TNF-α) combined to melphalan is clinically administered through isolated limb perfusion (ILP) for regionally advanced soft tissue sarcomas of the limbs. In preclinical studies, wild-type p53 gene is involved in the regulation of cytotoxic action of TNF-α and loss of p53 function contributes to the resistance of tumour cells to TNF-α. The relationship between p53 status and response to TNF-α and melphalan in patients undergoing ILP is unknown. Patients and methods: We studied 110 cases of unresectable limbs sarcomas treated by ILP. Immunohistochemistry was carried out using DO7mAb, which reacts with an antigenic determinant from the N-terminal region of both the wild-type and mutant forms of the p53 protein, and PAb1620mAb, which reacts with the 1620 epitope characteristic of the wild-type native conformation of the p53 protein. The immunohistochemistry data were then correlated with various clinical parameters. Results: P53DO7 was found expressed at high levels in 28 patients, whereas PAb1620 was negative in 20. The tumours with poor histological response to ILP with TNF-α and melphalan showed significantly higher levels of p53-mutated protein. Conclusions: Our results might be a clue to a role of p53 protein status in TNF-α and melphalan response in clinical us

    Limb salvage with isolated perfusion for soft tissue sarcoma: could less TNF-α be better?

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    Background: The optimal dose of TNF-α delivered by isolated limb perfusion (ILP) in patients with locally advanced soft tissue sarcoma is still unknown. Patients and methods: Randomised phase II trial comparing hyperthermic ILP (38-40°) with melphalan and one of the four assigned doses of TNF-α: 0.5 mg, 1 mg, 2 mg, and 3/4 mg upper/lower limb. The main end point was objective tumour response on MRI. Secondary end points were histological response, rate of amputation and toxicity. Resection of the remnant tumour was performed 2-3 months after ILP. The sample size was calculated assuming a linear increase of 10% in the objective response rates between each dose level group. Results: One hundred patients (25 per arm) were included. Thirteen per cent of patients had a systemic leakage with a cardiac toxicity in six patients correlated with high doses of TNF-α. Objective tumour responses were: 68%, 56%, 72% and 64% in the 0.5 mg, 1 mg, 2 mg and 3 or 4 mg arms, respectively (NS). Sixteen per cent of patients were not operated, 71% had a conservative surgery and 13% were amputated with no difference between the groups. With a median follow-up of 24 months, the 2 year overall and disease-free survival rates (95% CI) were 82% (73% to 89%) and 49% (39% to 59%), respectively. Conclusion: At the range of TNF-α doses tested, there was no dose effect detected for the objective tumour response, but systemic toxicity was significantly correlated with higher TNF-α doses. Efficacy and safety of low-dose TNF-α could greatly facilitate ILP procedures in the near futur
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