Sediment-Air Partitioning of Hydrophobic Organic Chemicals.

Contaminated sediments that become exposed to the air as a result of dredging or water receding are potential sources of emissions of toxic compounds to the atmosphere. Exposure models are currently being developed to assess the risk associated with this pathway of contaminant release and to design efficient remediation techniques. A critical parameter in these emission models is the equilibrium partition coefficient of the contaminant between the sediment and the air. In this study, the sediment-air equilibrium partitioning of a polymiclear aromatic hydrocarbon (phenanthrene) and a heterocyclic aromatic hydrocarbon (dibenzofuran) was investigated. Both classes of compounds are commonly found in contaminated sediments and are known carcinogens. A gas saturation technique was used to study the influence of ambient temperature and sediment moisture content on the partition coefficient of the contaminants. The primary factor affecting the partitioning is the sediment moisture content (mc). Its variation from about 0% to 6% causes the partition coefficient to decrease by up to three orders of magnitude. Determination of phenanthrene\u27s heat of sorption in dry (mc = 0.3%) and wet (mc \u3e 6.0%) sediments indicates that different mechanisms of sorption exist in each moisture range. In the dry range, the contaminant is mainly adsorbed on the mineral surfaces of the sediment. When the moisture content increases, the competitive adsorption of water progressively displaces the contaminant from the mineral adsorption sites. Finally, in the wet range, the contaminant is mainly associated with the sediment organic matter. In addition, the physical state of water in the sediment as a function of moisture content was characterized by comparing the isotherm of water sorption to the pore-volume distribution. This permitted the estimation of the respective contributions of the various sorption mechanisms to the overall sediment-air partitioning process. A model of the sediment-air partition coefficient is proposed that accurately accounts for the observed variations resulting from changes in sediment moisture content

Mobile phone use and temporal skin heat sensation

International audienceEpidemiological investigation of mobile phone (MP) users reported symptoms of discomfort feeling, warmth behind/around or on the ear and heat sensation of the cheek. These symptoms may be due to thermal insulation, conduction of the heat produced in the phone by the battery currents and running of the radiofrequency (RF) electronic circuits, and electromagnetic field (EMF) energy absorbed by the user's head. Using a Luxtron 790 fiberoptic thermometer we measured the temperature of the temporal skin due to GSM 1800 MHz MP radiated power (125 mW). We suppressed the EMF exposure by switching the RF signal from the antenna to a 50 O load. The ambient air temperature was 23°C and the MP was held in the normal position of use for 30 minutes to reach the thermal steady state. With a switched off MP, the increase in skin temperature was statistically significant 1.88°C. When MP was switched on, the increase was 2.93°C in reception mode, 3.29°C in emission mode without load and 3.31°C in emission mode with load. The temperature difference with or without load was not significant (tl7 = 0.707; p = 0.489), which means that the contribution of EMF absorption to skin heating is negligible. The result suggests that the heat sensations reported by the MP users are exclusively caused by thermal insulation and heat conduction from MP associated with long calling time

A Case of Paraneoplastic Demyelinating Motor Polyneuropathy

Peripheral neuropathy is commonly accompanied by cancer but demyelinating ones are not commonly reported. We report the clinical, neurophysiological, and biological characteristics of an 82-year-old patient who presented with a demyelinating motor neuropathy and high titre of anti-ganglioside antibodies associated with oesophageal cancer. The neurological course worsened rapidly despite immunotherapy, leading to a bedridden status. We propose to suspect a paraneoplastic origin in older patients or when the clinical course progresses rapidly within a few weeks or months

Patient perceptions of multiple sclerosis and its treatment

BACKGROUND: In order to improve the treatment outcome in multiple sclerosis, it is important to document the factors that influence adherence to therapy. The purpose of this study was to determine patient perceptions and awareness of multiple sclerosis and its treatment, treatment adherence, and impact on quality of life and daily living. METHODS: This was a cross-sectional observational study performed in France. Each participating neurologist included the first three patients with relapsing-remitting multiple sclerosis who consulted after the start of the study. Data on clinical features were collected from a physician questionnaire and on disease and treatment perception and on quality of life from a patient autoquestionnaire. RESULTS: A total of 175 neurologists entered 202 patients in the study. The mean duration of disease was 8.0 ± 7.0 years, and immunomodulatory treatment had been administered for a mean duration of 3.0 ± 2.0 years. A total of 166 patients (82.2%) were treated with interferon-β preparations and 36 patients (17.8%) with glatiramer acetate. Eighty-five patients (42.1%) reported missing their injections from time to time and 36 patients (17.8%) reported "drug holidays". The most frequently given reason for nonadherence was forgetfulness (38.7% of cases). Eighty-six patients (42.6%) and 70 patients (34.7%) claimed to be well informed about their disease and treatment, respectively. Adherence was significantly higher in well informed patients (P = 0.035). The majority of patients (176 patients, 87.1%) intended continuing their current treatment and 49.5% considered that their current treatment might reduce relapses. The most frequently reported side effect was muscle pain (124 patients, 61.4%). CONCLUSION: Patient understanding of treatment for disease enhances treatment adherence. Greater patient involvement in disease management requires better communication between physicians and their patients.journal article20122012 04 04importe

A comparative study between two different 3D reconstruction methods by bi-planar radiographic in upright posture: Biomod 3sand sterEOS®

ObjectivesThis study aims to evaluate the repeatability and reproducibility of two different methods of 3D reconstruction of the spine sterEOS® and BIOMODTM3S.Materials and methodsRepeatability and reproducibility study. Three observers performed the reconstructions: a radiologist, a X-ray technologist and a rehabilitation specialist, inexperienced in X-ray reading. The observers made these reconstructions with each modality: sterEOS® and BIOMODTM3S. The parameters investigated were Cobb angle, sagittal parameters (cyphosis, lordosis), determination of apical and junctional vertebrae, axial rotation of the apical vertebra, pelvic parameters and time of reconstruction. Statistical analyses were done using Intraclass Correlation Coefficient (ICC) for reproducibility and Student's t test for time of reconstruction.ResultsWe analyzed X-rays of 44 women (71%) and 18 men (29%) with a mean age of 44±20.8. The repeatability was correct, good or excellent depending on observer. The reproducibility inter-observer was correct to excellent (ICC 0.73–0.96) for every parameter except the axial rotation of the apical vertebrae and the determination of levels of junctional and apical vertebrae. The reproducibility of the axial rotation of apical vertebrae was low to good with BIOMODTM3S (ICC 0.15–0.81; ESM=7.5°). The reproducibility of the determination of levels of junctional and apical vertebrae was low to excellent with sterEOS® (ICC 0.36–0.90). With sterEOS®, the reproducibility was impaired by the inexperienced observator for some parameters. The 3D reconstructions with sterEOS® was significantly faster than with BIOMODTM3S (10.8min vs 14.2min, p<0.05).DiscussionParameters’ reproducibility is different depending on the system. The 3D reconstruction with sterEOS® is faster than with BIOMODTM3S. The reproducibility of BIOMODTM3S is less influenced by observator's experienc

Effects of 900 MHz radiofrequency on corticosterone, emotional memory and neuroinflammation in middle-aged rats

International audienceThe widespread use of mobile phones raises the question of the effects of electromagnetic fields (EMF, 900 MHz) on the brain. Previous studies reported increased levels of the glial fibrillary acidic protein (GFAP) in the rat's brain after a single exposure to 900 MHz global system for mobile (GSM) signal, suggesting a potential inflammatory process. While this result was obtained in adult rats, no data is currently available in older animals. Since the transition from middle-age to senescence is highly dependent on environment and lifestyle, we studied the reactivity of middle-aged brains to EMF exposure. We assessed the effects of a single 15 min GSM exposure (900 MHz ; specific absorption rate (SAR)=6 W/kg) on GFAP expression in young adults (6 week-old) and middle-aged rats (12 month-old). Brain interleukin (IL)-1ß and IL-6, plasmatic levels of corticosterone (CORT), and emotional memory were also assessed. Our data indicated that, in contrast to previously published work, acute GSM exposure did not induce astrocyte activation. Our results showed an IL-1ß increase in the olfactory bulb and enhanced contextual emotional memory in GSM-exposed middle-aged rats, and increased plasmatic levels of CORT in GSMexposed young adults. Altogether, our data showed an age dependency of reactivity to GSM exposure in neuro-immunity, stress and behavioral parameters. Reproducing these effects and studying their mechanisms may allow a better understanding of mobile phone EMF effects on neurobiological parameters

Effets des RF sur le système nerveux central : sommeil, EEG, vascularisation, cognition

National audienceLa plupart des études cliniques avec des champs RF ont étudié les effets d'expositions caractéristiques des téléphones portables, habituellement au niveau de la tête, sur un certain nombre de paramètres physiologiques comprenant le sommeil, l'activité électrique du cerveau, la cognition, la vascularisation cérébrale et plus généralement les systèmes cardiovasculaire et endocrinien. La majorité des études ont été effectuées chez des adultes en bonne santé. Il apparaît maintenant important d'étudier les effets des champs RF chez les enfants et les adolescents, étant donné la connaissance croissante d'une maturation continue du cerveau jusqu'à un stade avancé de l'adolescence, et quelques études récentes ont été effectuées avec des écoliers. Plusieurs études ont également porté sur des adultes qui déclarent être" électrosensibles "

Vieillissement actif : le maintien à domicile des baby-boomers

Cette recherche s’intéresse aux enjeux de l’habitat de demain de la génération des baby-boomers, tout particulièrement ceux nés entre 1945 et 1953, qui arrivent aujourd’hui à la retraite. C’est au carrefour de la vision de ce que signifie habiter selon des auteurs comme Benoit Goetz ( 2011), des philosophes comme Heidegger (1958), Bachelard (1957), Benjamin (1955), Büber (1962) ou encore Deleuze (1980) d’une part, soulignant les facteurs de porosité et les liens aux autres, et d’autre part les caractéristiques des baby-boomers telles que présentées par Jean François Sirinelli (2003) et Josée Garceau (2012), que se situe la recherche. Cette génération informée entend rester active et pratique des « adeptions » qui influencent par les gestes un savoir habiter et par là son habitat. L’étude de terrain a sondé les aspirations des baby-boomers en ce qui concerne leur choix résidentiel pour l’avenir, pour comprendre sur quelles valeurs et vers quels buts leur projet se construit. Le choix de méthodologies qualitatives s’appuie sur le visionnement préalable d’un film récent : Et si on vivait tous ensemble. Des entretiens semi-dirigés, auprès de cinq baby-boomers, de 60 à 65 ans, effectués en deux phases avec verbatim approuvés,étaient basés sur trois thèmes : la mémoire, l’adeption et le projet. Entre autres résultats, sont confirmés avec variantes, plusieurs concepts théoriques, comme ceux de porosité et d’ouverture par la fenêtre à la fois physique et virtuelle, mais soulignent le spectre de la maison de retraite et des préoccupations financières concernant l’avenir d’un habitat nécessairement autonome. Cette génération imprégnée par le monde technologique veut avoir accès à tout ce que propose la modernité sans pour autant perdre le sens de l’historicité de leur vie. Nés dans un monde en bouillonnement, les baby-boomers ont réinventé chaque étape de leur existence, ce qui laisse préfigurer que cette génération s’apprête à réinventer la retraite et ses sites domiciliaires. Aussi l’approche design devra-t-elle complètement se renouveler pour ces nouveaux usagers.This study is about the stakes of how the baby boomer generation, in particular those born between 1945 and 1954 who are currently retiring, will deal with their living spaces. I shall take into account the multiple visions of Benoit Goetz (2011), Heidegger (1958), Bachelard (1957), Benjamin (1955), Büber (1962) and Deleuze (1980) who analyze what it means to live in a given living space. Indeed not only must porosity factors and increasing relations between beings be analyzed but also the characteristics of these baby boomers themselves with regards to who they are as Jean Francois Sirinelli (2003) and Josée Garceau (2012) have done. This new generation of baby boomers hopes to remain active and in order to do so seeks to adapt and influence their living spaces as well as their conceptualizations of what it means to “live”. This current study has asked baby boomers what their visions are for their future residential choices in order to grasp on what values and for what goals their project is based on,. This was done by having five baby boomer between the age of 60-65 to watch the movie Et si on vivait tous ensemble. Afterwards, semi-directed interviews, based on their memory of the movie, what adaptions they foresee in addition to how they see their future, were conducted in two different phases with approved verbatim. The findings were then compared and confirmed with different theoretical frameworks such as porosity and opening of a physical and virtual window. At the same time, retirement homes and the financial considerations behind an aging population were taken into account. This generation, immersed in technology wants to have access to such modern technology without losing the feeling of controlling their lives and story. Born in an innovation and changing time, they have already proven capable of changing and reinventing each stage of their life. This, therefore, leaves us to believe that they will do the same with their vision of retirement and living spaces. Hence, tomorrow’s design models will have to renew itself for its new users