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1.
Opt Lett ; 49(13): 3632-3635, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38950227

ABSTRACT

High-energy laser facilities require high reflection multilayer coatings on meter-scale substrates. Due to stringent use specifications, a precise control of deposition parameters is necessary to tailor the optical and mechanical properties of components. The resulting coatings are sensitive to relative humidity variations, leading to a shift of their optical spectra called spectral shift. This spectral shift is generally observed on a narrow range, near the operating wavelength. Here we extend the concept of spectral shift to a broader spectral range. This analysis serves as a tool to study the behavior of a multilayer coating spectrum with relative humidity. To validate the spectral shift determination method, we compared the spectral shift of single layers induced by the relative humidity with simulated optical properties induced by either thickness or refractive index variations. In addition to the validation of the approach, the fitting results and the comparison between spectral shift shapes show that relative humidity variations mainly impact the refractive index of the layers and SiO2 is more sensitive than HfO2.

2.
Mar Pollut Bull ; 128: 140-155, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29571357

ABSTRACT

3D coupled modeling approach is used for the PCB dispersion assessment in the Gulf of Lion and its transfer to zooplankton via biogeochemical processes. PCB budgets and fluxes between the different species of PCB: dissolved, particulate, biosorbed on plankton, assimilated by zooplankton, which are governed by different processes: adsorption/desorption, bacteria and plankton mortality, zooplankton excretion, grazing, mineralization, volatilization have been estimated. Model outputs were compared with the available in situ data. It was found that the Rhone River outflows play an important role in the organism contamination in the coastal zone, whereas the atmospheric depositions are rather more important in the offshore zones. The transfer of the available contaminant to bacteria and phytoplankton species is mainly related to the biomass present in the water column. Absorption fluxes (grazing) to zooplankton are rather higher than the passive sorption fluxes, which are themselves also linked to the sorption coefficient.


Subject(s)
Environmental Monitoring/methods , Models, Theoretical , Polychlorinated Biphenyls/analysis , Water Pollutants, Chemical/analysis , Animals , Biomass , Food Chain , France , Phytoplankton/chemistry , Phytoplankton/growth & development , Rivers/chemistry , Seawater/chemistry , Spatio-Temporal Analysis , Zooplankton/chemistry , Zooplankton/growth & development
3.
Sci Total Environ ; 409(21): 4618-27, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-21855959

ABSTRACT

Brominated flame retardants (BFRs) were investigated in juvenile common sole from nursery zones situated along the French coast in 2007, 2008 and 2009. Extensive identification was performed with regard to PBDEs, novel BFRs 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), and other non-PBDE BFRs, namely, hexabromobenzene (HBB) and 2,2',4,4',5,5'-hexabromobiphenyl (BB-153). Polybrominated diphenyl ether (PBDE) concentrations (Σ 14 congeners) ranged from 0.01 ng/g to 0.16 ng/g wet weight (ww) in muscle, and 0.07 ng/g to 2.8 ng/g ww in liver. Concentrations were in the lower range of those reported in the literature in other European locations. Lower PBDE concentrations, condition indices and lipid contents were observed in the Seine estuary in 2009, possibly in relation to a lower water flow. The PBDE patterns and ratios we observed suggested that juvenile sole have a relative high metabolic degradation capacity. Non-PBDE BFRs were detected at lower levels than PBDEs, i.e., within the < method detection limit - 0.005 ng/g ww range in muscle, and < method detection limit - 0.2 ng/g ww range in liver. The data obtained is of particular interest for the future monitoring of these compounds in the environment.


Subject(s)
Benzene Derivatives/analysis , Environmental Monitoring/methods , Flame Retardants/analysis , Flatfishes/metabolism , Gas Chromatography-Mass Spectrometry/methods , Halogenated Diphenyl Ethers/analysis , Water Pollutants, Chemical/analysis , Animals , Benzene Derivatives/metabolism , Flame Retardants/metabolism , France , Gas Chromatography-Mass Spectrometry/veterinary , Halogenated Diphenyl Ethers/metabolism , Liver/chemistry , Muscles/chemistry , Seasons , Water Pollutants, Chemical/metabolism
4.
Environ Pollut ; 159(1): 229-237, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20888677

ABSTRACT

The uptake and elimination of six PBDE congeners (BDE-28, -47, -99, -100, -153, -209) were studied in juvenile common sole (Solea solea L.) exposed to spiked contaminated food over a three-month period, then depurated over a five-month period. The results show that all of the studied PBDEs accumulate in fish tissues, including the higher brominated congener BDE-209. Several additional PBDE congeners were identified in the tissues of exposed fish, revealing PBDE transformation, mainly via debromination. The identified congeners originating from PBDE debromination include BDE-49 and BDE-202 and a series of unidentified tetra-, penta-, and hepta- BDEs. Contaminant assimilation efficiencies (AEs) were related to their hydrophobicity (log Kow) and influenced by PBDE biotransformation. Metabolism via debromination appears to be a major degradation route of PBDEs in juvenile sole in comparison to biotransformation into hydroxylated metabolites.


Subject(s)
Diet , Flatfishes/metabolism , Halogenated Diphenyl Ethers/metabolism , Animals , Biotransformation , Environmental Monitoring , Polybrominated Biphenyls/metabolism
5.
Environ Pollut ; 158(12): 3527-33, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20864231

ABSTRACT

The uptake, elimination and transformation of six PBDE congeners (BDE-28, -47, -99, -100, -153, -209) were studied in juvenile common sole (Solea solea L.) exposed to spiked contaminated food over a three-month period, and then depurated over a five-month period. Methoxylated (MeO-) and hydroxylated (OH-) PBDEs were determined in fish plasma exposed to PBDEs and compared to those obtained in control fish. While all MeO- and some OH- congeners identified in fish plasma were found to originate from non-metabolic sources, several OH- congeners, i.e., OH-tetraBDEs and OH-pentaBDEs, were found to originate from fish metabolism. Among these, 4'-OH-BDE-49 was identified as a BDE-47 metabolite. Congener 4'-OH-BDE-101, identified here for the first time, may be the result of BDE-99 metabolic transformation. Our results unequivocally showed that PBDEs are metabolised in juvenile sole via the formation of OH- metabolites. However, this was not a major biotransformation route compared to biotransformation through debromination.


Subject(s)
Flatfishes/metabolism , Halogenated Diphenyl Ethers/pharmacokinetics , Mixed Function Oxygenases/metabolism , Animals , Biotransformation , Diet , Environmental Monitoring , Halogenated Diphenyl Ethers/blood , Hydroxylation
6.
Chemosphere ; 73(6): 945-53, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18701131

ABSTRACT

The levels and temporal trends of toxic polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in archived marine mussels collected between 1981 and 2005 from selected sites along French coasts. The geographical distribution and levels of PCDD/Fs generally reflect regional inputs of these contaminants: the highest concentrations were determined in samples from the Seine river estuary (English Channel) and Toulon area (Mediterranean coast); the lowest levels were determined in Corsica (Mediterranean Sea). PCDD/F isomeric composition showed a fairly homogeneous distribution pattern throughout the various sampling sites. This pattern, dominated by 2,3,7,8-TCDF and OCDD, can be considered as typical for the study species. However, on a more local scale, some differences in isomeric composition in mussels were identified in relation to local source characteristics. The time trend study showed a pronounced decrease in PCDD/F concentrations over the 24-year period at most sites, except Toulon on the Mediterranean Sea, where the decrease was not significant. This overall decrease probably reflects the general drop in PCDD/F emissions in Europe since 1980. However, high concentrations were determined in mussels collected in recent years (1999, 2001 and 2005) from the mouth of the Seine river. These concentrations are related to particular hydrological conditions, and intensive sediment dredging due to a new port construction at the mouth of the estuary. The results presented in this paper provide reference data on the contamination of shellfish by persistent organic pollutants in the marine environment.


Subject(s)
Benzofurans/chemistry , Bivalvia/chemistry , Polychlorinated Dibenzodioxins/analogs & derivatives , Water Pollutants, Chemical/chemistry , Animals , Bivalvia/metabolism , Dibenzofurans, Polychlorinated , France , Oceans and Seas , Polychlorinated Dibenzodioxins/chemistry , Time Factors , Water Pollutants, Chemical/metabolism
7.
Environ Pollut ; 156(1): 123-35, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18243453

ABSTRACT

Ambient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment and mussels in a semi-enclosed marine ecosystem (Thau lagoon, France). Sigma2,3,7,8-PCDD/F and sigma7ICES PCB air concentrations (0.2-1.4 and 31-57 pg m(-3), respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476 fg L(-1)) and low for PCBs (138-708 pg L(-1)). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33 ng g(-1) d.w., respectively) and mussel (13-21 pg g(-1) d.w. and 10-39 ng g(-1) d.w., respectively) were medium levels. PCDD/F congener patterns observed in air, water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fs into the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs in the mentioned compartments.


Subject(s)
Polychlorinated Biphenyls/analysis , Polychlorinated Dibenzodioxins/analogs & derivatives , Water Pollutants, Chemical/analysis , Air Pollutants/analysis , Animals , Bivalvia/metabolism , Ecosystem , Environmental Monitoring/methods , Geologic Sediments/chemistry , Polychlorinated Dibenzodioxins/analysis , Seawater/chemistry
8.
J Chromatogr A ; 930(1-2): 9-19, 2001 Sep 28.
Article in English | MEDLINE | ID: mdl-11681583

ABSTRACT

A procedure is presented which allows the ultratrace level determination of phenylurea herbicides (PUHs) in natural waters. Samples were enriched by solid-phase extraction (SPE) on Carbopack B and alkylated with iodoethane and sodium hydride to yield thermostable products. After derivatization, the aqueous samples were extracted and injected by SPME. The use of iodoethane instead of iodomethane allowed the differentiation between parent compounds and the N-demethylated metabolites. Limits of detection were between 0.3 and 1.0 ng/l for the parent compounds. Standard deviations below 10% were achieved for samples containing more than 4 ng/l in very different matrices including Nanopure water, lake water, and waste water treatment plant (WWTP) effluent. Moreover, the para-hydroxylated metabolite of diuron could be quantified with the same procedure. The presence of further metabolites was assessed qualitatively. Chromatography was stable over a large number of measurements even with dirty samples from WWTP effluent. The precision and sensitivity of the developed analytical method allowed the investigation of the fate of PUHs in lakes, their degradation during drinking water treatment and their transport within the North Sea.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Herbicides/analysis , Phenylurea Compounds/analysis , Water Pollutants, Chemical/analysis , Calibration , Reproducibility of Results
9.
Environ Toxicol Chem ; 20(7): 1381-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11434279

ABSTRACT

The degradation products of diuron (photoproducts and metabolites), already described in the literature, were synthesized in order to carry out further investigations. Their ecotoxicity was determined using the standardized Microtox test, and most of the derivatives presented a nontarget toxicity higher than that of diuron. Therefore, the biotransformation of these compounds was tested with four fungal strains and a bacterial strain, which were known to be efficient for diuron transformation. With the exception of the 3,4-dichlorophenylurea, all the degradation products underwent other transformations with most of the strains tested, but no mineralization was observed. For many of them, the biodegradation compound for which the toxicity was important was 3,4-dichlorophenylurea. This study underlines the importance of knowing the nature of the degradation products, which has to be kept in mind while analyzing natural water samples or soil samples.


Subject(s)
Diuron/toxicity , Bacteria , Biodegradation, Environmental , Diuron/analogs & derivatives , Diuron/chemical synthesis , Diuron/metabolism , Fungi , Herbicides , Phenylurea Compounds , Toxicity Tests , Vibrio/drug effects , Vibrio/physiology
11.
Rev Laryngol Otol Rhinol (Bord) ; 114(3): 155-60, 1993.
Article in French | MEDLINE | ID: mdl-8191056

ABSTRACT

Based on 8 observations, the authors analyze the extension of middle ear cholesteatomas on the anterior attic and the anterior supralabyrinthine cellular groove, the internal retrotympanum and the posterior sublabyrinthine cellular groove, the hypotympanum and the anterior sublabyrinthine groove, the retrolabyrinthine region and the translabyrinthine and posterior supralabyrinthine grooves. Despite progress in imaging and optical instrumentation, exact precision of the lesions sometimes remains impossible. The patient must be warned of a possible enlargement of the operative pathway and its consequences.


Subject(s)
Cholesteatoma/surgery , Ear Diseases/surgery , Petrous Bone , Adult , Child , Ear, Middle , Female , Humans , Male , Tympanoplasty/methods
12.
Ann Otolaryngol Chir Cervicofac ; 109(5): 240-4, 1992.
Article in French | MEDLINE | ID: mdl-1292379

ABSTRACT

Over the last 24 years the authors operated 21 branchiomeric paragangliomas in 18 patients. They emphasize the difficulty of making the diagnosis and the importance of completing a thorough work-up before deciding surgery. Adequate imaging is particularly important (neck sonography, computed tomography, arteriography) to avoid making the diagnosis by exploratory neck dissection and to assess the vascular risk. Biological studies have regained importance, especially in the context of complex neuro-cristopathy. Treatment is essentially surgical and must be considered with prudence in patients with bilateral lesions. The surgical removal of branchiomeric paragangliomas necessitates preparation of a small saphenous vein bypass in case it is not possible to avoid sacrificing the internal carotid artery.


Subject(s)
Branchioma/surgery , Carotid Body Tumor/surgery , Cranial Nerve Neoplasms/surgery , Head and Neck Neoplasms/surgery , Paraganglioma/surgery , Vagus Nerve , Adult , Branchioma/diagnosis , Carotid Body Tumor/diagnosis , Cranial Nerve Neoplasms/diagnosis , Diagnostic Imaging , Female , Head and Neck Neoplasms/diagnosis , Humans , Male , Middle Aged , Paraganglioma/diagnosis , Paraganglioma/genetics
13.
Ann Otolaryngol Chir Cervicofac ; 109(1): 23-31, 1992.
Article in French | MEDLINE | ID: mdl-1575415

ABSTRACT

INTRODUCTION: This work has been carried out to investigate in an animal model, the possibility of surgical selective reinnervation of the larynx following destruction of the laryngeal branch of the vagus nerve. MATERIAL AND METHODS: In ten dogs, on the right side of the neck only, the recurrent laryngeal nerve was identified, cut and section of the nerve removed. Following this the hemi-larynx on the operated side was reinnervated in the following manner. Using a microsurgical suture (described in the text) the motor nerves from extra-laryngeal muscles were anastomosed onto the nerves supplying the intrinsic abductors and adductors of the larynx. The nerve to sterno-thyroid was anastomosed onto the nerve supplying the posterior crico-arytenoid muscle (vocal cord abductor). Similarly the nerve supplying thyrohyoid was anastomosed onto the cut distal end of the adductor division of the recurrent laryngeal nerve. Clinical, electromyographical and histological evaluations have been used to prove the reinnervation. RESULTS: In the nine surviving animals successful re-innervations, as defined by the return of normal function, has been achieved for posterior crico-arytenoid and 7 adductor muscles. CONCLUSION: This study has demonstrated the feasibility of laryngeal reinnervation after surgical section of the recurrent laryngeal nerve, and give some cause for optimism for its ultimate application in man.


Subject(s)
Recurrent Laryngeal Nerve/surgery , Suture Techniques , Vocal Cord Paralysis/surgery , Anastomosis, Surgical , Animals , Dogs , Electromyography , Female , Microsurgery , Neck Muscles/innervation , Research
14.
Ann Biol Clin (Paris) ; 47(1): 41-4, 1989.
Article in French | MEDLINE | ID: mdl-2930020

ABSTRACT

Precise identification and determination of MICs of clinical isolates of Acinetobacter identified to other species than the hospital species A. baumannii were carried out. On 260 Acinetobacter strains isolated in an hospital over a 6 months period, 31 strains (12 p. cent) were identified to species other than A. baumannii. Among these 31 strains, A. Iwoffii sensu stricto (16 strains) and A. haemolyticus (6 strains) were mostly recovered. Eight glucose oxidizing strains were identified to A. haemolyticus (6 strains), Acinetobacter genospecies 3 (2 strains), and A. Iwoffii sensu stricto (1 strain). Antibiotic susceptibilities of these strains were greater than those commonly observed with A. baumannii strains.


Subject(s)
Acinetobacter/isolation & purification , Anti-Bacterial Agents/pharmacology , Acinetobacter/drug effects , Humans
15.
Am J Otol ; 9(4): 286-92, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3177611

ABSTRACT

In 533 surgical procedures for cholesteatoma, a closed technique was used in 60%, an obliteration technique with Palva flap was used in 35%, and an open technique was used in 5%. The closed technique has been done in stages in the authors' institution since 1973. The obliteration technique was only staged if the mesotympanum was dissected. In some cases, the Palva flap was partially lifted from the bone to check posterior cavities. A closed technique in one stage provided intact tympanic membrane in 97% of cases, but retraction pocket occurred in 25%; ABG was within 20 dB in 68% of ears if the stapes was intact and in 40% if crura were missing. Obliteration technique in one stage (if the mesotympanum was normal) provided intact tympanic membrane in 100% of cases, but one late residual cholesteatoma under the flap eroded the semicircular canal after 5 years. ABG within 20 dB was achieved in 68% of the ears if the stapes was intact and in 40% if crura were missing. Closed technique in two stages with Silastic sheeting achieved intact tympanic membrane in 97% of the ears. Residual cholesteatoma was removed at the second stage in 24% of the ears. ABG within 20 dB was achieved in 57% of the ears if stapes was intact and in 52% if crura were missing. Ten percent of the ears underwent an obliteration transformation at the second stage because of large mesotympanum cholesteatoma or retraction pocket. Late retraction pockets were observed in 10% of cases. Obliteration technique in two stages provided an intact tympanic membrane in 96.8% of the ears.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cholesteatoma/surgery , Ear Diseases/surgery , Adult , Bone Conduction , Child , Cholesteatoma/physiopathology , Follow-Up Studies , Hearing , Humans , Methods
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