59 research outputs found
Commotonicity and maximum stop-loss premiums.
No full textIn this paper, we investigate the relationship between comonotonicity and stop-loss order. We prove our main results by using a characterization of stop-loss order within the framework of Yaari's (1987) dual theory of choice under risk. Wang and Dhaene (1997) explore related problems in the case of bivariate random variables. We extend their work to an arbitrary sum of random variables and present several examples illustrating our results.
Renal insufficiency, a frequent complication with age in oral-facial-digital syndrome type I.
No full textpeer reviewedSaal S, Faivre L, Aral B, Gigot N, Toutain A, Van Maldergem L, Destree A, Maystadt I, Cosyns J-P, Jouk P-S, Loeys B, Chauveau D, Bieth E, Layet V, Mathieu M, Lespinasse J, Teebi A, Franco B, Gautier E, Binquet C, Masurel-Paulet A, Mousson C, Gouyon J-B, Huet F, Thauvin-Robinet C. Renal insufficiency, a frequent complication with age in oral-facial-digital syndrome type I. The oral-facial-digital syndrome type I (OFD I) is characterized by multiple congenital malformations of the face, oral cavity and digits. A polycystic kidney disease (PKD) is found in about one-third of patients but long-term outcome and complications are not well described in the international literature. Renal findings have been retrospectively collected in a cohort of 34 females all carrying a pathogenic mutation in the OFD1 gene with ages ranging from 1 to 65 years. Twelve patients presented with PKD - 11/16 (69%) if only adults were considered -with a median age at diagnosis of 29 years [IQR (interquartile range) = (23.5-38)]. Among them, 10 also presented with renal impairment and 6 were grafted (median age = 38 years [IQR = (25-48)]. One grafted patient under immunosuppressive treatment died from a tumor originated from a native kidney. The probability to develop renal failure was estimated to be more than 50% after the age of 36 years. Besides, neither genotype-phenotype correlation nor clinical predictive association with renal failure could be evidenced. These data reveal an unsuspected high incidence rate of the renal impairment outcome in OFD I syndrome. A systematic ultrasound (US) and renal function follow-up is therefore highly recommended for all OFD I patients
CNS involvement in OFD1 syndrome: a clinical, molecular, and neuroimaging studyOral-Facial-Digital Type I
No full textOral-facial-digital type 1 syndrome (OFD1; OMIM 311200) belongs to the expanding group of disorders ascribed to ciliary dysfunction. With the aim of contributing to the understanding of the role of primary cilia in the central nervous system (CNS), we performed a thorough characterization of CNS involvement observed in this disorder
Propriétés physiques de films minces de phtalocyanines adsorbées sur des semi-conducteurs III-V
No full textDans ce mémoire, nous présentons une étude des propriétés physiques (ordre, structures vibrationnelle et électronique) en surface et à l'interface de films minces de phtalocyanines (Pcs) adsorbées sur des surfaces (001) de semi-conducteurs III-V (InSb, InAs). Nous avons utilisé les techniques d'analyse de surfaces suivantes : la microscopie à effet tunnel (STM), la diffraction d'électrons lents (LEED), la spectroscopie de perte d'énergie d'électrons lents à haute résolution (HREELS) et la spectroscopie d'absorption de rayons X (NEXAFS). Sur InSb(001)-4x2/c(8x2), les données STM et LEED montrent que les molécules s'adsorbent préférentiellement sur les rangées d'Indiun du substrat. En monocouche, les Pcs adoptent une reconstruction (4nx3), caractérisée par un ordre unidimensionnel à grande échelle suivant la direction [110]. Les mesures effectuées par HREELS et NEXAFS révèlent que les molécules s'adsorbent "à plat" sur la surface. De plus, elles montrent qu'il n'y a aucune modification des modes propres ni des molécules ni du substrat, sous l'effet de l'adsorption. Ainsi, nous suggérons que leur interaction est faible (physisorption). Ces résultats ont été observés pour trois différents systèmes : PbPc, SnPc, H2Pc adsorbées sur InSb. Sur InAs(001)-4x2/c(8x2), les mesures STM et LEED révèlent que l'arrangement moléculaire est similaire à celui décrit précédemment. Cependant, les données HREELS présentent des différences notables par rapport à celles enregistrées sur InSb. Elles semblent indiquer l'existence d'une interaction molécule-substrat plus importante (chimisorption ?)AIX-MARSEILLE1-BU Sci.St Charles (130552104) / SudocSudocFranceF
Ion energy distribution functions and Langmuir probe measurements in low pressure argon discharges
No full textAssociation d'une aplasie cutanée congénitale et d'une coarctation de l'aorte: association fortuite ?
No full textGenomic deletions of OFD1 account for 23% of oral-facial-digital type 1 syndrome after negative DNA sequencing.
No full textPulsed DC bias for the study of negative-ion production on surfaces of insulating materials in low pressure hydrogen plasmas
No full textInternational audienceIn this work negative-ion production on the surface of a sample negatively DC biased in a hydrogen plasma is studied. The negative ions created under the positive ion bombardment are accelerated towards the plasma, self-extracted and detected according to their energy and mass, by a mass spectrometer placed in front of the sample. The use of a pulsed bias allows applying a quasi-DC bias on insulating material during a short period of time and offers the possibility to extend the measurement method to nonconductive samples. The pulsed-bias tests were performed first with Highly Oriented Pyrolitic Graphite (HOPG), a conductive material, to demonstrate the feasibility of the method. By changing the pulsed-bias frequency it was possible to obtain HOPG material with different hydrogen surface coverages and hence different surface states leading to an increase of negative-ion production by up to 30-50% as compared to the continuous bias case. To establish a protocol for insulating materials, charge accumulation on the surface during the bias pulse and influence of the bias duration and frequency were explored using microcrystalline diamond (MCD) thin layers. By using a pulse short enough (10 µs) at 1 kHz frequency, it has been possible to measure negative-ions on MCD sample at a quasi-constant surface bias of 130 V, with only 1 V variation during the measurement. Negative-ion surface production on MCD has been studied in pulsed mode with surface temperature from room temperature to 800°C. It is shown that pulsing the bias and increasing the temperature allows limiting defect creation on MCD which is favorable for negative-ion production. Consequently, at 400°C the yield on MCD in pulsed mode is one order of magnitude higher than the yield on HOPG in continuous mode at room temperature
Surface production of negative deuterium ions from plasma-exposed boron doped diamond and graphite: work function measurements using photoemission yield spectroscopy
No full textInternational audienceNegative-ion sources are of considerable interest for applications such as materials processing and neutral beam injection for magnetic confinement fusion. The efficient production of negative ions in these sources often relies on surface production. Work function measurements are critical to enable a detailed understanding of the mechanisms that underpin this. In this study we used a combination of photoemission yield spectroscopy and the Fowler method to determine the work functions of boron doped diamond (BDD) and highly oriented pyrolytic graphite (HOPG) directly after exposure to a low-pressure inductively coupled deuterium plasma (150 W, 2 Pa). A magnetised retarding field energy analyser is used to measure the negative ion current from the samples. During plasma exposure, samples are biased at −130 V or −60 V and their temperature is varied between 50 ∘ C and 750 ∘ C. The results show that the increasing work function of the plasma exposed HOPG occurs over the same sample temperature range as the decreasing negative-ion current. In contrast, the work function of BDD does not show a clear relationship with negative-ion current, suggesting that different mechanisms influence the negative-ion production of metal-like HOPG and dielectric-like BDD. The necessity for an additional fitting parameter for the Fowler fits to BDD suggests that its electronic properties are changing under plasma exposure, unlike HOPG. For both materials, the maximum photocurrent measured from the samples displays a strong similarity with negative-ion current, suggesting they are driven by a common mechanism. The in-situ measurement of the work function using non-invasive techniques is of interest for the development of negative ion sources
Genetic and serological heterogeneity of the supertypic HLA-B locus specificities Bw4 and Bw6
No full textGene cloning and sequencing of the HLA-B
locus split antigens B38 (B16.1) and B39 (B16.2) allowed
localization of their subtypic as well as their public
specificities HLA-Bw4 or -Bw6 to the c~-helical region of
the c~ 1 domain flanked by the amino acid positions 74-83.
Comparison of their amino acid sequences with those of
other HLA-B-locus alleles established HLA-Bw6 to be
distinguished by Ser at residue 77 and Asn at residue 80.
In contrast, HLA-Bw4 is characterized by at least seven
different patterns of amino acid exchanges at positions 77
and 80-83. Reactivity patterns of Bw4- or Bw6-specific
monoclonal antibodies reveal two alloantigenic epitopes
contributing to the HLA-Bw4 or -Bw6 specificity residing
next to the region of highest diversity of the cr domain
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