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Bauxite extraction by-products (red mud) were used to evaluate their potential ability to stabilize trace elements from dredged and aerated/humidified marine sediment. The investigated by-products were: bauxaline ® (BX) that is a press-filtered red mud; bauxsol™(BS) that is a press-filtered red mud previously washed with excess of seawater, and gypsum neutralized bauxaline ® (GBX). These materials were separately mixed to dredged composted sediment sample considering 5% and 20% sediment: stabilizer ratios. For pilot experiments, rainfall events were regularly simulated for 3 months. Concentrations of As, Mo, Cd, Cr, Zn, Cu, and Ni were analyzed in collected leachates as well as toxicity. Results showed that Cd, Mo, Zn, and Cu were efficiently stabilized in the solid matrix when 20% of BX, BS, and GBX was applied. Consequently, toxicity of leachates was lower than for the untreated sediment, meaning that contaminants mobility was reduced. A 5% GBX was also efficient for Mo, Zn and Cu stabilization. In all scenarios, As stabilization was not improved. Compared to all other monitored elements, Mo mobility seemed to depend upon temperature-humidity conditions during pilot experiments suggesting the need of further investigations. [ABSTRACT FROM AUTHOR]

The management of dredged sediments is a priority issue in the Mediterranean sea where sediments are historically polluted. The aims of this study were to evaluate the toxicity of port sediment samples and the effect of three mineral additives (hematite, zerovalent iron (ZVI) and natural zeolite (NZ)) on sediment elutriate toxicity. Four sediments (A, B, C and D) were provided by port authorities after composting procedure; particle size, particulate organic carbon, metals and organic pollutants (TBT, PAHs, PCBs) were determined in whole sediments. Elutriates from these composted sediments were analyzed by determining toxicity level using oyster (Crassostrea gigas) larvae bioassay, metal and dissolved organic carbon concentrations. Toxicity, measured on undiluted elutriates (250g/L), decreased as follows: A≥B>C∼D. The treatment of sediments with mineral additives (5%) revealed that hematite tends to decrease the elutriate toxicity in all samples, particularly in samples B and C. This effect may be related to metal concentration decrease in elutriates, in particular Cu and Zn, that have a significant toxic effect on oyster larvae. ZVI and NZ have a variable influence on elutriate toxicity. Results suggest that hematite may be a possible candidate for decreasing chemical concentration and improving the quality of elutriates. Hematite could be used for sediment stabilization prior to the deposit in a specific site or landfill. [Copyright &y& Elsevier]

Abstract: A new sequential method for the determination of both natural (U, Th) and anthropogenic (Sr, Cs, Pu, Am) radionuclides has been developed for application to soil and sediment samples. The procedure was optimised using a reference sediment (IAEA-368) and reference soils (IAEA-375 and IAEA-326). Reference materials were first digested using acids (leaching), ‘total’ acids on hot plate, and acids in microwave in order to compare the different digestion technique. Then, the separation and purification were made by anion exchange resin and selective extraction chromatography: transuranic (TRU) and strontium (SR) resins. Natural and anthropogenic alpha radionuclides were separated by uranium and tetravalent actinide (UTEVA) resin, considering different acid elution medium. Finally, alpha and gamma semiconductor spectrometer and liquid scintillation spectrometer were used to measure radionuclide activities. The results obtained for strontium-90, cesium-137, thorium-232, uranium-238, plutonium-239+240 and americium-241 isotopes by the proposed method for the reference materials provided excellent agreement with the recommended values and good chemical recoveries. Plutonium isotopes in alpha spectrometry planchet deposits could be also analysed by ICPMS. [Copyright &y& Elsevier]

Objective: Spontaneous nasal cerebrospinal fluid (CSF) leaks are frequently linked to idiopathic intracranial hypertension (IIH). The objectives of our study were: (1) to determine the rate of transverse venous sinus stenosis (TVSS) in patients with spontaneous nasal CSF leak and in patients with IIH without CSF (controls), and (2) to study the correlation between spontaneous nasal CSF leak and brain imaging features., Study Design: A multicenter retrospective case-control study., Setting: Six French tertiary hospitals., Methods: Patients with spontaneous nasal CSF leaks and patients with IIH without nasal CSF leaks (controls) were included. The transverse venous sinus patency was analyzed by magnetic resonance imaging to identify possible stenosis or hypoplasia., Results: Thirty-two patients with spontaneous nasal CSF leaks and 32 controls were included. TVSS was significantly more frequent in patients with spontaneous nasal CSF leaks than in controls (p = .029). Univariate analysis indicated that TVSS (odds ratio, OR: 4.2; 95% confidence interval, CI [1.352-14.915]; p = .017) and arachnoid granulations (OR: 3; 95% CI [1.065-8.994]; p = .042) were risk factors for spontaneous nasal CSF leak. In multivariate analysis, TVSS and arachnoid granulations were independent risk factors of nasal CSF leak (OR: 5.577, 95% CI [1.485-25.837], p = .016; and OR: 4.35, 95% CI [1.234-17.756], p = .029, respectively)., Conclusion: This multicenter case-control study shows that TVSS is an independent risk factor for CSF leak in patients with IIH. Stenosis management by interventional radiology may be proposed postoperatively to increase the success of IIH surgical treatment or preoperatively to reduce the need for surgery., (© 2023 American Academy of Otolaryngology-Head and Neck Surgery Foundation.)

Background and Aims: Since the COVID-19 pandemic, several studies have reported a decrease in adolescents' well-being. We aim to describe life satisfaction over the last decade and examine the factors associated with its variations between 2020 and 2021 among French students in their last year of middle school (around 14-15 years old)., Methods: Data were drawn from a repeated biennial cross-sectional national survey conducted in French schools over the last decade (EnCLASS study), using a self-administered questionnaire. After describing life satisfaction trends between 2012 and 2021 using the Cantril ladder, we examined individual changes in life satisfaction between 2020 and 2021 and their associations with housing and studying conditions during the COVID-19 lockdown, using multinomial logistic regression analysis (decrease, increase, no change as reference)., Results: Among the 17,686 survey respondents, an overall slight decrease in the prevalence of adolescents reporting high life satisfaction (i.e., Cantril score ≥6) was observed since 2012 with the lowest proportion reported in 2021 (77.4%). Between 2020 and 2021, 16.3% of French adolescents experienced an improvement in life satisfaction, while 17.7% experienced the opposite. Decrease in life satisfaction between 2020 and 2021 was more likely experienced by adolescents living in reconstructed families [aOR 2.09 (95%CI, 1.58-2.77)], those who did not have their own room [aOR 1.58 (1.16-2.15)], nor access to the Internet to interact with their friends during the lockdown [aOR 1.47 (1.09-1.98)]. Interestingly, more girls than boys were represented in both those reporting increase and decrease in life satisfaction [aOR 1.82 (1.40-2.37) and 1.43 (1.14-1.79), respectively]., Conclusions: This study shows that the way adolescents experienced the first 2020 lockdown in France was not uniform, and that one must consider sex as well as housing and studying conditions when interpreting adolescents' life satisfaction decrease during the COVID-19 pandemic., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Hurel, Ehlinger, Molcho, Cohen, Falissard, Sentenac and Godeau.)

Purpose: The purpose of our study was to investigate the impact of HPV status in oncologic outcomes in patients with T1-2 oropharyngeal SCC associated with bulky N3 nodes, and to determine progression prognosis factors aiming to define the best therapeutic strategies for these patients., Methods: This multicenter retrospective study included patients with T1-2 oropharyngeal SCC with N3 nodes treated between 2010 and 2015 in 8 French comprehensive cancer centers. HPV status was determined with P16 hyperexpression in immunohistochemistry. HPV-positive patients were separated into 2 groups according to the associated smoking history (HPV + T +) or not (HPV + T-). We compared the oncological outcomes of patients according to HPV-status and smoking history., Results: Of 67 patients with T1-2 N3 oropharyngeal SCC, 36 patients (53.7%) were HPV negative and 31 patients (46.3%) HPV positive. 2-year PFS was significantly better in HPV + T- group (p = 0.036). The risk of death or progression was significantly reduced in HPV + T- comparatively to HPV- (HR 0.25 95%CI [0.07; 0.89]). 2-year OS was significantly better in HPV + T- group than in the other two groups (p = 0.017)., Conclusion: In patients with T1-2 oropharyngeal SCC associated with bulky N3 nodes, HPV positive patients without smoking history had better OS and PFS than HPV positive patients with smoking history and HPV negative patients. Thus, HPV status is a significant prognostic factor for survival but this benefit is altered when smoking history is associated. N3 HPV positive patients with smoking history have to be classified as high-risk., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This paper (part II) is devoted to the effect of molecular adsorption on the surface of magnetic iron oxide nanoparticles (IONP) on the enhancement of their (secondary) field-induced agglomeration and magnetic separation. Experimentally, we use Methylene Blue (MB) cationic dye adsorption on citrate-coated maghemite nanoparticles to provoke primary agglomeration of IONP in the absence of the field. The secondary agglomeration is manifested through the appearance of needlelike micron-sized agglomerates in the presence of an applied magnetic field. With the increasing amount of adsorbed MB molecules, the size of the field-induced agglomerates increases and the magnetic separation on a magnetized micropillar becomes more efficient. These effects are mainly governed by the ratio of magnetic-to-thermal energy α, suspension supersaturation Δ 0 , and Brownian diffusivity D eff of primary agglomerates. The three parameters (α, Δ 0 , and D eff ) are implicitly related to the surface coverage θ of IONP by MB molecules through the hydrodynamic size of primary agglomerates exponentially increasing with θ. Experiments and developed theoretical models allow quantitative evaluation of the θ effect on the efficiency of the secondary agglomeration and magnetic separation.

This series of two papers is devoted to the effect of organic dye (methylene blue, MB; or methyl orange, MO) adsorption on the surface of either bare or citrate-coated magnetic iron oxide nanoparticles (IONPs) on their primary agglomeration (in the absence of an applied magnetic field) and secondary field-induced agglomeration. The present paper (Part I) is focused on physicochemical mechanisms of dye adsorption and adsorption-induced primary agglomeration of IONPs. Dye adsorption to oppositely charged IONPs is found to be mostly promoted by electrostatic interactions and is very sensitive to pH and ionic strength variations. The shape of adsorption isotherms is correctly reproduced by the Langmuir law. For the particular MB/citrated IONP pair, the maximum surface density of adsorbed MB seems to correspond to the packing density of an adsorbed monolayer rather than to the surface density of the available adsorption sites. MB is shown to form H-aggregates on the surface of citrate-coated IONPs. The effective electric charge on the IONP surface remains nearly constant in a broad range of surface coverages by MB due to the combined action of counterion exchange and counterion condensation. Primary agglomeration of IONPs (revealed by an exponential increase of hydrodynamic size with surface coverage by MB) probably comes from correlation attractions or π-stacking aromatic interactions between adsorbed MB molecules or H-aggregates. From the application perspective, the maximum adsorption capacity is 139 ± 4 mg/g for the MB/citrated IONP pair (pH = 4-11) and 257 ± 16 mg/g for the MO/bare IONP pair (pH ∼ 4). Citrated IONPs have shown a good potential for their reusability in water treatment, with the adsorption efficiency remaining about 99% after nine adsorption/desorption cycles., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Introduction: Established in France since 2018, the Student Health Service aims to train students to become actors in health education., Methods and Results: A teaching system lasting the equivalent of six weeks full-time has been set up in the third year of medical school in Rennes. The aim is for students to develop the skills needed to carry out interventions based on a project approach, with a variety of audiences, on priority public health themes.New pedagogical approaches have been developed to integrate learning about health promotion and health education into the medical curriculum. Innovations have been implemented: work on the educational posture, tutoring of third-year students by medical interns, a forum for simulation of concrete actions under the supervision of a dual thematic and population-based expertise. Beyond the acquisition of knowledge, the training aims to encourage a reflective approach and is based on peer education.The 240 students of the faculty prepare their project in trinomials throughout the academic year. Their activities take place over ten half-days in more than a hundred establishments in the faculty subdivision and enable them to work with approximately 10,000 people per year., Discussion: Education and health promotion now occupies a central place in the training of third-year students, an essential condition for the sustainable acquisition of this field of expertise by future health professionals.

Red mud is a solid waste of bauxite processing by Bayer process which involves caustic digestion of Al-containing mineral for alumina production. The global inventory of red mud waste reached an estimated amount of 4 billion tons in 2015, increasing at an approximate rate of 120 million tons per year. Therefore, its management is becoming a global environmental issue for the protection of environment, and the need for awareness in this regard is becoming crucial. Although red mud is not considered as a hazardous material in many countries, its high alkalinity and fine particle size may pose significant environmental threat, and it is found to be an interesting material for environmental remediation purposes due to rich iron content. This paper provides a review of possible remedial applications of red mud in various environmental compartments. Modification of red mud creates novel opportunities for cost-effective and efficient removal of metal ions, inorganic anions, dyes, and phenols from wastewater and acid mine drainage. Re-vegetation of red mud disposal sites, treatment of metal-contaminated acidic soils presents the usefulness of this material but less research has been done so far to investigate its use in the stabilization of polluted sediments. On the other hand, leaching and eco-toxicological tests have also revealed that red mud does not pose high toxicity to the environment making it suitable for the treatment of contaminated media. Nevertheless, neutralization of red mud is recommended for its safe disposal and secure application in any environmental media.

In-situ capping of polluted sediment is considered as an inexpensive and effective treatment technology to immobilize contaminants in a short time. In this remediation technique sediments are capped by placing a layer of sand, clean sediment or other materials over sediments in order to mitigate risk. In this study, low cost industrial by products (bauxaline, steel slag, and mixture of the two products) were applied as capping agents. A bench scale laboratory experiment in aquariums was performed to evaluate their effects on Cd, Zn, As, and Cr mobility from an artificially contaminated marine sediment. Without capping, all the contaminants are constantly released with various kinetic depending of mineral oxidation or dissolution or leaching. Nevertheless, release did not exceed 31% of the initial amount of pollutant. Capping sediment with steel slag, bauxaline and their mixture totally captured Cd, Zn, and As. In the case of Cr, only steel slag actively blocked its release. A kinetic model was developed to model As and Cr release, with and without capping. The release times for Cr and As from the sediment were close to 6 days. In the presence of capping agents, the capture time for Cr was found to be 57 days for steel slag, and 7 days for bauxaline. Despite a high capture time, steel slag was the best capping agent since bauxaline matrix was a source of Cr and rapidly released it (release time = 1 day). The results indicated that steel slag and its mixture additive can be used as potential capping materials for the remediation of contaminated sites due to their significant entrapping of Cd, Zn, As, and Cr., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Effects of functionalization and grafting of TiO 2 , CeO 2 , and SiO 2 nanoparticles (NPs) were investigated, and toxicity of pristine, functionalized, and grafted NP towards Daphnia magna was measured. Surface functionalization of NP with amine groups decreased hydrophobicity of NP. When NPs were hydrophilic, they were less toxic than hydrophobic NP towards D. magna. Grafting agents influenced toxicity: no toxicity of NP was observed when bio-based and hydrogenated synthetic polymers were used, whereas perfluorinated polymers induced a higher toxicity.

The concentration, potential mobility, cation exchange capacity and toxicity of eight sediment-bound metals in Golfe-Juan Bay, France were examined. Results revealed significant spatial gradient of metal contamination along Golfe-Juan coast. The distribution and concentration of the metals appear to be influenced by the geochemical properties of the sediment, proximity to anthropogenic sources and general water circulation in the bay. The portion of trace metals found in the exchangeable, carbonate, oxidizable and reducible fractions of the sediment constitute 31%-58% of the total sediment-bound trace metal content, suggesting significant potential for remobilization of metals into the water column. Pb and Ni content of the sediment exceed the limits of the French marine sediment quality. Whole sediment extracts showed acute toxicity to marine rotifers. This study concludes that monitoring and management of sediment-bound trace metals in Golfe-Juan Bay are important so as not to underestimate their availability and risk to the marine ecosystems., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In this work, magnetic nanoparticles of iron oxide (MNPs) were synthesized, and then the surface was recovered with an oleate double layer in order to investigate the ability of this material to adsorb nickel ions. First, the solution chemistry of oleate ions was investigated in order to determine the critical micellar concentration (CMC) value and the arrangements of ions above the CMC. Then, the synthesized oleate-modified MNP was characterized (TEM, DLS, XRD, FTIR, zeta potential, magnetometry). Finally, adsorption experiments were carried out as a function of pH and as a function of nickel concentration in 0.1 g L -1 suspensions of oleate-modified MNP. The results show that CMC of oleate ranges from 1 to 2.5∙10 -3  mol L -1 . Above CMC, arrangement of oleate ions as droplets, vesicles, or micelles depends on pH and influences the average size and solution absorbance. Potentiometric titrations allowed determining a pKa value of 7.8 for sodium oleate. The high stability in aqueous suspensions and characterization of oleate-modified MNP confirm that oleate ions are arranged as a bilayer coating at the surface of MNP. Retention of nickel was found to be highly dependent on pH, with a maximum adsorption (90%) beginning from pH = 7.5. The sorption isotherms were well fitted with the Langmuir model and the maximum nickel adsorption capacities were found to be 44 and 80 mg g -1 for pH = 6.8 and 7.2, respectively. The efficient removal of nickel combined with the magnetic properties of the NMP make the oleate-modified MNP an interesting water purification tool.

Management of marine dredged sediments polluted with trace elements is prime issue in the French Mediterranean coast. The polluted sediments possess ecological threats to surrounding environment on land disposal. Therefore, stabilization of contaminants in multi-contaminated marine dredged sediment is a promising technique. Present study aimed to assess the effect of gypsum neutralized bauxaline(®) (bauxite residue) to decrease the availability of pollutants and inherent toxicity of marine dredged sediment. Bauxaline(®), (alumia industry waste) contains high content of iron oxide but its high alkalinity makes it not suitable for the stabilization of all trace elements from multi-contaminated dredged sediments. In this study, neutralized bauxaline(®) was prepared by mixing bauxaline(®) with 5% of plaster. Experiments were carried out for 3 months to study the effect of 5% and 20% amendment rate on the availability of Cu, Cd, Zn, As, Mo, and Cr. Trace elements concentration, pH, EC and dissolved organic carbon were measured in all leachates. Toxicity of leachates was assessed against marine rotifers Brachionus plicatilis. The Results showed that both treatments have immobilization capacity against different pollutants. Significant stabilization of contaminants (Cu, Cd, Zn) was achieved with 20% application rate whereas As, Mo, and Cr were slightly stabilized. Toxicity results revealed that leachates collected from treated sediment were less toxic than the control sediment. These results suggest that application of neutralized bauxaline(®) to dredged sediment is an effective approach to manage large quantities of dredged sediments as well as bauxite residue itself., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Stabilization of marine dredged sediments contaminated with multi-elements is a challenging task in choosing the appropriate sorbent and application dosage. The present study investigates the possibility of using bauxite residues (Bauxaline® and Bauxsol) as amendment for the treatment of contaminated sediment. A pilot scale experiment was conducted for three months to stabilize trace elements in composted contaminated sediment sample using 5% by-product amendment. The results showed that after 3months of treatment, cationic trace elements were effectively immobilized but increased leaching of anionic pollutants was observed. Increased leaching of anionic pollutants could be limited by addition of higher quantities of amendments. The total content of available pollutants decreased in stabilized sediments but this treatment has no effect on the classification of waste. The leachates were then evaluated for acute toxicity using estuarine rotifers Brachionus plicatilis. Bauxite residues can be inexpensive choices for the stabilization of cationic pollutants in dredged sediments., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Polyacrylamides are polymers used in many fields and represent the main source of release of the highly toxic acrylamide in the environment. In this work, a simple, rapid, and sensitive analytical method was developed with HPLC/MS/MS and direct injection for acrylamide analysis in water and adsorption samples. AFNOR standards NF T90-210 and NF T90-220 were used for the analytical method validation and uncertainty estimation. Limit of quantification (LOQ) for acrylamide was 1 μg/L, and accuracy was checked at three acrylamide levels (1, 6, and 10 μg/L). Uncertainties were estimated at 34.2, 22, and 12.4 % for acrylamide concentrations at LOQ, 6 μg/L, and 10 μg/L, respectively. Acrylamide adsorption on clays (kaolinite, illite) and sludge was then studied as a function of pH, time, and acrylamide concentrations. Acrylamide adsorption on kaolinite, illite, and sludge was found to be very weak since adsorption percentages were inferior to 10 %, whatever the pH value and the initial acrylamide concentration. The low affinity of acrylamide for clays and sludge is likely due to its hydrophilic property, small size, and charge neutrality.

The management of dredged sediments is an important issue in coastal regions where the marine sediments are highly polluted by metals and organic pollutants. In this paper, mineral-based amendments (hematite, zero-valent iron and zeolite) were used to stabilize metallic pollutants (As, Cd, Cu, Mo, Ni, Pb, and Zn) in a contaminated marine sediment sample. Mineral-based amendments were tested at three application rates (5 %, 10 %, and 15 %) in batch experiments in order to select the best amendment to perform column experiments. Batch tests have shown that hematite was the most efficient amendment to stabilize inorganic pollutants (As, Cd, Cu, Mo, Ni, Pb, and Zn) in the studied sediment. Based on batch tests, hematite was used at one application rate equal to 5 % to conduct column experiments. Column tests confirmed that hematite was able to decrease metal concentrations in leachates from stabilized sediment. The stabilization rates were particularly high for Cd (67 %), Mo (80 %), and Pb (90 %). The Microtox solid phase test showed that hematite could decrease significantly the toxicity of stabilized sediment. Based on batch and column experiments, it emerged that hematite could be a suitable adsorbent to stabilize metals in dredged marine sediment.

Trace element pollution of marine dredged sediments is an emerging problem all over the world. Comparing to other wastes, trace elements stabilization is more difficult both due to the wide range of contaminants present in the marine sediments and their inherent physicochemical properties. In this study, a pilot-scale experiment was performed to stabilize As, Cd, Cu, Mo, Ni, and Zn in a multi-contaminated sediment sample using hematite, zero-valent iron and zeolite. Results showed that iron-based amendments were able to reduce the leaching and the bioavailability of trace elements in the sediment sample, while zeolite was unsuitable. Chemical stabilization through iron-based amendments seems to be a promising approach as a low-cost alternative to traditional stabilization methods involving chemical reagents., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Numerous nanomaterials have recently been developed, and numerous practical applications have been found in water treatment, medicine, cosmetics, and engineering. Associative polymers, such as hydrophobically modified alkali-soluble emulsion (HASE) systems are involved in several applications and have been extensively studied due to their ability to form three-dimensional networked gels. However, the data on the potential environmental effects of this polymers are scarce. The aim of this study is to assess the effect of functionalisation of silica nanoparticles, and coupling of functionalised silica nanoparticles to the associative polymer HASE on their toxicity. Thus, acute and chronic toxicity tests included a modified acute test (72 h) using daphnies, algae, and plants as model organisms. Gradient of toxicity varied with the tested organisms. Our results revealed that the functionalised nanoparticules and NP grafted polymer cause a global decrease in toxicity compared to commercial nanoparticule and HASE polymer., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This work investigates arsenic mobility, bioavailability and toxicity in marine port sediments using chemical sequential extraction and laboratory toxicity tests. Sediment samples were collected from two different Mediterranean ports, one highly polluted with arsenic and other inorganic and organic pollutants (Estaque port (EST)), and the other one, less polluted, with a low arsenic content (Saint Mandrier port (SM)). Arsenic distribution in the solid phase was studied using a sequential extraction procedure specifically developed for appraising arsenic mobility in sediments. Toxicity assessment was performed on sediment elutriates, solid phases and aqueous arsenic species as single substance using the embryo-toxicity test on oyster larvae (Crassostrea gigas) and the Microtox test with Vibrio fischeri. Toxicity results showed that all sediment samples presented acute and sub-chronic toxic effects on oyster larvae and bacteria, respectively. The Microtox solid phase test allow to discriminate As-contaminated samples from the less contaminated ones, suggesting that toxicity of whole sediment samples is related to arsenic content. Toxicity of dissolved arsenic species as single substance showed that Vibrio fischeri and oyster larvae are most sensitive to As(V) than As(III). The distribution coefficient (Kd) of arsenic in sediment samples was estimated using results obtained in chemical sequential extractions. The Kd value is greater in SM (450 Lkg(-1)) than in EST (55 Lkg(-1)), indicating that arsenic availability is higher for the most toxic sediment sample (Estaque port). This study demonstrates that arsenic speciation play an important role on arsenic mobility and its bioavailability in marine port sediments., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

With the rapid development of nanotechnology, there is an increasing risk of human and environmental exposure to nanotechnology-based materials. However, the data on the potential environmental effects of nanoparticles are scarce. The aim of this study is to assess the effect of particle size and crystal structure (anatase and rutile) of titanium dioxide on their toxicity. Thus, acute and chronic toxicity tests included a modified acute test (72 h) using daphnies and algae, rotifers and plants as model organisms. Gradient of toxicity varied with the tested biological organisms. Our results revealed that TiO(2) nanoparticles in anatase crystal structure are toxic in the entire set of tests conducted. However, at highconcentration, through their antimicrobial properties, they significantly promoted growth of roots. Because of its lipophilicity, the rutile crystalline structure of TiO(2) NPs form larger aggregates in aqueous medium; then they have less effect on biological organisms, and thus a lower toxicity than the anatase crystalline form of TiO(2). We also demonstrated that exposure duration, aggregation and concentrations are contributing factors in nanoparticles-mediated toxicity., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The determination of enthalpies of reactions (aqueous and surface complexation) is used in this work to model the temperature effect on the adsorption processes. Microcalorimetry experiments were carried out to determine the enthalpy of adsorption of europium on γ-alumina at 25 °C. The stability constants at 50 °C were then calculated with the van't Hoff equation, and a 2-pK approach was used to model the adsorptive behavior of Eu on alumina at 50 °C, as a function of pH. The results have shown that the adsorption of Eu(3+) on the alumina surface is weakly endothermic. In the experimental conditions considered in the present study, the temperature has only a small effect on the adsorption reaction., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The aim of this work is to assess the potential ecotoxicological effects of contaminated sediments treated with mineral additives. The Microtox solid phase test was used to evaluate the effect of mineral additives on the toxicity of sediment suspensions. Four Mediterranean port sediments were studied after dredging and bioremediation: Sample A from navy harbor, sample B from commercial port and samples C and D from pleasure ports. Sediment samples were stabilized with three mineral additives: hematite, zero-valent iron and zeolite. Results show that all studied mineral additives can act as stabilizer agent in highly contaminated sediments (A and C) by decreasing dissolved metal concentrations and sediment toxicity level. On the contrary, for the less contaminated samples (B and D) hematite and zeolite can provoke toxic effect towards Vibrio fischeri since additive particles can favor bacteria retention and decrease bioluminescence emission., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

This work investigates the ecotoxicological evaluation of contaminated dredged sediments from French Mediterranean navy harbour (A), commercial port (B) and two composite specimens (C) and (D) coming from the mixture of A and B with other port sediments. The toxicity of elutriates from these sediments is estimated using embryo-toxicity test, Microtox® solid phase test, LuminoTox, phytotoxicity tests and genotoxicity test. Bioassay responses are not clearly correlated with chemical contamination in the whole sediment and vary as a function of tested organisms. The highest contaminated samples (A and C) are almost always more toxic than the less contaminated samples (B and D). Among composite sediments, the mixture effect with other sediments is not efficient to decrease toxicity in sample C, suggesting that other parameters influence toxicity level such as particle size or organic matter content. These parameters should be taken into consideration in order to improve the efficiency of the mixture process and produce composite sediments with low toxicity., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The ecotoxicological effect of dredged sediments was estimated by embryo-larval toxicity of the oyster Crassosstrea gigas in sediment elutriates (filtered and unfiltered). The study covers the main ports from the French Mediterranean coast. Composted sediments from a navy harbour (A), a commercial port (B) and two composite specimens (C and D) obtained after mixing various sediments were taken into consideration. Effective concentrations affecting 50% of larvae (EC50) were obtained from different elutriate concentrations (from 0 to 100%). Toxicity results obtained from filtered elutriates decreased according to the following gradient: sample A (5.68%), B (20.50%), C (37.60%) and D (47.17%). Chemical concentrations in whole sediments were in agreement with those in elutriates. Among the measured contaminants in elutriates, Cu and Zn resulted as the main contributors to toxicity. Dissolved organic carbon played an important role by exerting a protective effect against the toxicity of dissolved Cu. Toxicity results were interpreted on the basis of toxicity scores to give indication about sediment quality which provided more severe judgement than risk score based on chemical concentrations in sediments., (Copyright 2009 Elsevier Ltd. All rights reserved.)

The aim of this work is to study the performances of removal of hexavalent chromium from aqueous solution by three different oxy-hydroxides: hematite, goethite and alpha-alumina. Batch experiments were conducted to measure the effects on adsorption of Cr(VI) of different parameters such as pH of the medium, ionic strength, and initial concentration. Results showed that the adsorption of Cr(VI) depends strongly on the pH, but is independent of ionic strength for hematite and goethite. For alpha-alumina, adsorption is strongly dependent on pH values and ionic strength. Equilibrium studies showed that Cr(VI) had a high affinity in an acidic medium, but decreased as solution pH increased. Equilibrium isotherms were measured experimentally. Results were analyzed by the Langmuir and Freundlich equations using linearized correlation coefficient at room temperature. The characteristic parameters for each isotherm have been determined. Langmuir equation was found to fit the equilibrium data for Cr(VI) adsorption.

The enthalpy changes associated with the protonation and deprotonation of an alumina surface have been determined on the basis of microcalorimetry experiments and acid-base potentiometric titrations at 25 degrees C. It has been shown that the results may vary significantly according to the experimental procedure. In order to do so, the potentiometric and microcalorimetric titrations have been carried out first from an acidic pH to basic pH and second from a pH near the pH(zpc) of alumina to acidic or basic pH. It has been demonstrated that the pK(a) values deduced from the potentiometric titrations are the same whatever the experimental protocol whereas the only way to obtain meaningful enthalpies of proton exchange is to carry out microcalorimetric titrations by starting around the point of zero charge.

In neurogenesis, little is known about signal transduction pathways upstream of gene expression however, mounting evidence suggests that calcium release from internal stores plays a critical role. We have previously demonstrated that BM88 is a neuronal lineage-specific regulator of cell cycle exit and differentiation; we now report a link between BM88 and calcium signaling. Calcium imaging experiments revealed that P2Y-induced calcium mobilization is diminished in mouse neuroblastoma Neuro 2a cells stably transfected with BM88 (N2A-BM88 cells) as compared with N2A cells or N2A cells differentiated with retinoic acid. This effect is not restricted to N2A cells but is also observed in HeLa cells that are transiently transfected with BM88, indicating that cells of both neural and non-neural origin respond similarly. Further, activation of P2Y1 but not purinergic P2X receptors induces proliferation of N2A and to a lesser extent of N2A-BM88 cells. Conversely, knockdown of BM88 facilitates N2A cell proliferation both under stimulating and non-stimulating conditions. Importantly, N2A-BM88 cells are less susceptible to apoptosis triggered by C2-ceramide and exhibit reduced C2-ceramide-induced intracellular calcium release. Higher calcium uptake from mitochondria and/or lower calcium levels inside the endoplasmic reticulum may explain the reduced calcium mobilization in response to BM88. Overall, our data reveal a novel signaling mechanism by which BM88 interferes with calcium release from inositol 1,4,5-trisphosphate-sensitive stores and exerts anti-proliferative and anti-apoptotic functions.

Histone deacetylase inhibitors arrest the growth of neuroblastoma cells and induce differentiation. Identification of target genes that co-ordinate and mediate these effects is important for understanding the function of this novel class of antitumour drugs. We report here that trichostatin-A (TSA) specifically induces the transcription of Cend1, a neuronal-lineage specific regulator of cell cycle exit and differentiation, in neuroblastoma Neuro2A cells, but not in non-neuronal cells. Furthermore, we show that knockdown of Cend1 alleviates both the anti-proliferative and differentiation effect of TSA. Our findings suggest that Cend1 is an important molecular target for HDAC inhibition.

The heels of 23 patients who were diagnosed with unilateral/bilateral plantar fasciitis were evaluated via ultrasonography and compared with their asymptomatic feet and a control group of 23 people. Plantar fascial thickness, echogenity, and heel pad thickness were evaluated, and the results were statistically analyzed. For symptomatic feet, increased thickness of the fascia and reduced echogenity were constant ultrasonographic findings (mean, 4.79 mm for symptomatic feet; 2.17 mm for control group, P < .05). No significant difference was found between heel pads of the diseased and healthy feet (mean, 12.96 mm for symptomatic feet; 13.10 mm for control group; P > .05). Ultrasonography seems to be a valuable, noninvasive diagnostic tool for the evaluation of plantar fasciitis.

Control of cell cycle progression/exit and differentiation of neuronal precursors is of paramount importance during brain development. BM88 is a neuronal protein associated with terminal neuron-generating divisions in vivo and is implicated in mechanisms underlying neuronal differentiation. Here we have used mouse neuroblastoma Neuro 2a cells as an in vitro model of neuronal differentiation to dissect the functional properties of BM88 by implementing gain- and loss-of-function approaches. We demonstrate that stably transfected cells overexpressing BM88 acquire a neuronal phenotype in the absence of external stimuli, as judged by enhanced expression of neuronal markers and neurite outgrowth-inducing signaling molecules. In addition, cell cycle measurements involving cell growth assays, BrdUrd incorporation, and fluorescence-activated cell sorting analysis revealed that the BM88-transfected cells have a prolonged G(1) phase, most probably corresponding to cell cycle exit at the G(0) restriction point, as compared with controls. BM88 overexpression also results in increased levels of the cell cycle regulatory protein p53, and accumulation of the hypophosphorylated form of the retinoblastoma protein leading to cell cycle arrest, with concomitant decreased levels and, in many cells, cytoplasmic localization of cyclin D1. Conversely, BM88 gene silencing using RNA interference experiments resulted in acceleration of cell proliferation accompanied by impairment of retinoic acid-induced neuronal differentiation of Neuro 2a cells. Taken together, our results suggest that BM88 plays an essential role in regulating cell cycle exit and differentiation of Neuro 2a cells toward a neuronal phenotype and further support its involvement in the proliferation/differentiation transition of neural stem/progenitor cells during embryonic development.

Sorption reactions on natural or synthetic materials that can attenuate the migration of pollutants in the geosphere could be affected by temperature variations. Nevertheless, most of the theoretical models describing sorption reactions are at 25 degrees C. To check these models at different temperatures, experimental data such as the enthalpies of sorption are thus required. Highly sensitive microcalorimeters can now be used to determine the heat effects accompanying the sorption of radionuclides on oxide-water interfaces, but enthalpies of sorption cannot be extracted from microcalorimetric data without a clear knowledge of the thermodynamics of protonation and deprotonation of the oxide surface. However, the values reported in the literature show large discrepancies and one must conclude that, amazingly, this fundamental problem of proton binding is not yet resolved. We have thus undertaken to measure by titration microcalorimetry the heat effects accompanying proton exchange at the alumina-water interface at 25 degrees C. Based on (i) the surface sites speciation provided by a surface complexation model (built from acid-base titrations at 25 degrees C) and (ii) results of the microcalorimetric experiments, calculations have been made to extract the enthalpic variations associated respectively to first and second deprotonation of the alumina surface. Values obtained are deltaH1 = 80+/-10 kJ mol(-1) and deltaH2 = 5+/-3 kJ mol(-1). In a second step, these enthalpy values were used to calculate the alumina surface acidity constants at 50 degrees C via the van't Hoff equation. Then a theoretical titration curve at 50 degrees C was calculated and compared to the experimental alumina surface titration curve. Good agreement between the predicted acid-base titration curve and the experimental one was observed.

BM88 is a neurone-specific protein implicated in cell cycle exit and differentiation of neuronal precursors. It is widely expressed in terminally differentiated neurones but also in neuronal progenitors, albeit in lower levels. Thus BM88 expression shows a tight correlation with the progression of progenitor cells towards neuronal differentiation. Here we report the genomic organization and proximal promoter characterization of the human and mouse BM88 genes. Both promoters lie in a CpG island, are TATA-less and have multiple transcription start sites. Deletion analysis performed on the human BM88 gene revealed an 88 bp minimal promoter fragment that is preferentially active in neural cells. Importantly, this minimal promoter is sufficient to confer specific transcriptional activity in primary neurones, but not in glial cells. Within the promoter region there are four functional Sp1-binding sites. Simultaneous mutations to all four Sp1 sites results in complete loss of promoter activity. Transactivation experiments revealed that Sp1 directly activates the BM88 promoter while activation also occurs in the presence of neurogenin-1. Characterization of the promoter elements that control neurone-specific and developmental expression of BM88 should contribute to the elucidation of the transcriptional networks that regulate the transition from a proliferative neural progenitor to a post-mitotic neurone.