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The purpose was to assess the psychometric properties of the French version of the Young Schema Questionnaire - Short Form 3 (YSQ–S3). The main non-clinical sample (N = 605, M = 20.63, 78% women) was divided into two subsamples: One was used for exploratory factor analyses (EFA) and the other was used for confirmatory analyses. Next, internal consistency, convergent validity and criterion-related validity were studied. The EFA to each of the five domains was similar to the theoretical structure postulated by Young. The confirmatory analysis of each of the five domains appeared to favor our solution over a single-factor solution and Young’s solution. The confirmatory factor analyses of high-order structures did not give fully satisfactory results but appeared to favor our solution (RMSEA =.11, CFI =.76, TLI =.71, SRMR =.07, AIC = 58,566.44). In our best model, the reliability (> .70) was satisfactory for fourteen schemas. The relationships between the schemas and the neuroticism, extraversion and psychoticism scores went in the expected directions. Detrimental parental rearing behaviors were linked to high scores for the various schemas. Lastly, 4 schemas differentiated between the clinical and non-clinical groups. In conclusion, the overall psychometric qualities of the French version of the YSQ–S3 allow its use in clinical populations.
Synchrotron-based x-ray techniques are used to bring complementary information to local probes such as atom probe tomography and transmission electron microscopy. Two examples of nuclear materials used for the cladding of fuel assembly are given: oxide dispersion strengthened (ODS) alloys and M5™ Zr-based alloys. In both cases, synchrotron radiation analyses bring original results concerning nanosized secondary phases: for M5™, radiation-enhanced precipitation of β-Nb precipitates has been evidence and the crystallographic structure (lattice parameter and Nb content) is reported for the first time and for irradiated ODS, the dissolution of larger oxides is evidenced while a finer distribution of complex Y–Ti–O oxides still acts as obstacles for dislocations.
In the present paper, we present a dynamic gate biasing technique applied to a 10 W, S-band GaN amplifier. The proposed methodology addresses class-B operation of power amplifiers that offers the potential for high efficiency but requires a careful attention to maintain good linearity performances at large output power back-off. This work proposes a solution to improve the linearity of class-B amplifiers driven by radio frequency-modulated signals having large peak to average power ratios. An important aspect of this work concerns the characterization of the dynamic behavior of GaN devices for gate bias trajectory optimization. For that purpose, the experimental study reported here is based on the use of a time-domain envelope setup. A specific gate bias circuit has been designed and connected to a 10 W – 2.5 GHz GaN amplifier demo board from CREE. Compared to conventional class-B operation with a fixed gate bias, a 10-dB improvement in terms of third-order intermodulation is reached. When applied to the amplification of 16-QAM signals the proposed technique demonstrates significant ACPR reduction of order of 6 dB along with error vector magnitude (EVM) improvements of five points over 8 dB output power back-off with a minor impact on power-added efficiency performances.
A vascular corrosion cast of an entire mouse kidney was scanned with a modular multiresolution X-ray nanotomography system. Using an isotropic voxel pitch of 0.5 μm, capillary systems such as the vasa recta, peritubular capillaries and glomeruli were clearly resolved. This represents a considerable improvement over corrosion casts scanned with microcomputed tomography systems. The resolving power of this system was clearly demonstrated by the unique observation of a dense, subcapsular mat of capillaries enveloping the entire outer surface of the cortical region. Resolution of glomerular capillaries was comparable to similar models derived from laser scanning confocal microscopy. The high-resolution, large field of view and the three-dimensional nature of the resulting data opens new possibilities for the use of corrosion casting in research.
There are currently two optical interferometry recombiners that can provide spectral resolutions better than 10000, AMBER/VLTI operating in the H-K bands, and VEGA/CHARA, recently commissioned, operating in the visible. These instruments are well suited to study the wind activity of the brightest AB supergiants in our vicinity, in lines such as Hα or Brγ. We present here the first observations of this kind, performed on Rigel (B8Ia) and Deneb (A2Ia). Rigel was monitored by AMBER in two campaigns, in 2006-2007 and 2009-2010, and observed in 2009 by VEGA; whereas Deneb was monitored in 2008-2009 by VEGA. The extension of the Hα and Brγ line forming regions were accurately measured and compared with CMFGEN models of both stars. Moreover, clear signs of activity were observed in the differential visibility and phases. These pioneer observations are still limited, but show the path for a better understanding of the spatial structure and temporal evolution of localized ejections using optical interferometry.
The aim of the LUCAS program is to observe chlorophyll and atmospheric molecules in the Earthshine spectrum in order to prepare the detection of life in terrestrial extrasolar planets to be discovered. Actually, observations from Antarctica offer a unique possibility to study the variations of Earthshine spectrum during Earth rotation while various parts of Earth are facing the Moon. Special instrumentation for the LUCAS program was designed and put in the Concordia station in the Dome C. Observations are in progress.
This paper presents a technique that enables both efficiency and linearity enhancements of power amplifiers (PA) used in communication systems. It consists in the implementation of a dynamic bias control combined with digital base-band predistortion. The aim of this paper is to describe a methodology and successive steps of the design procedure to reach optimum performances in terms of power added efficiency (PAE) and linearity. It is here applied to a 100 W wide-band lateral diffused metal oxide semiconductor (LDMOS) push–pull amplifier (50–500 MHz) driven by orthogonal frequency division multiplexing (OFDM) signals. When the amplifier is driven by a continuous wave (CW) signal and operates at a constant 28 V drain bias voltage, it exhibits 100 W output power and 60% PAE. When it is driven by an OFDM signal, a 10 dB output power back-off is necessary to have a −25 dBc adjacent channel power ratio (ACPR) and PAE decreases down to 10%. By properly implementing an envelope tracking bias system, 40 W output power along with 38% PAE and −27 dBc ACPR have been reached. Applying base-band digital predistortion provides additional linearity improvements at high PAE (for only one point PAE lost, a 5 dB improvement is obtained for ACPR).
Fluorochrome marking of the gastropod Concholepas concholepas has shown that the prismatic units of the shell are built by superimposition of isochronic growth layers of about 2 μm. Fluorescent growth marks make it possible to establish the high periodicity of the cyclic biomineralization process at a standard growth rhythm of about 45 layers a day. Sulphated polysaccharides have been identified within the growth layers by using synchrotron radiation, whereas high resolution mapping enables the banding pattern of the mineral phase to be correlated with the layered distribution of polysaccharides. Atomic force microscopy has shown that the layers are made of nanograins densely packed in an organic component.
The LIBS technique (laser-induced breakdown spectroscopy) has been applied mainly for the bulk analysis of solids , liquids , or gases , but more sparsely for elemental microanalysis of solid surfaces. In this chapter we describe different results obtained with a micro LIBS device devoted to element distribution analysis on solid surfaces and to localized analysis. The crater diameter and its shape are two crucial parameters that have to be well controlled to obtain reliable results. After a description of different published results concerning micro plasmas and recent applications of surface analysis, a complete description of a laboratory micro LIBS device is reported. The smallest crater diameter achieved with the experimental set-up and that can be used for analytical purposes is 3 μm. An original device offering an attractive feature to obtain regular spaced craters is also presented. The characteristics of the system in terms of quantitative analysis are highlighted. Different element distributions on surfaces of ceramics and steel samples are shown to demonstrate the very high potential of micro LIBS for elemental microanalysis. Finally, the micro LIBS technique is presented as a powerful analytical method for geological samples.
The use of a microscope combined with a laser has been reviewed previously . This present chapter provides information on technical details of manufactured microanalyzers combined with a spark-gap device, positioned above the sample surface, to make localized analysis. With the different manufactured systems, crater diameters from laser ablation could vary from 10 μm to 1 mm.
In this paper we report the heteroepitaxial growth and the structural evolution of hexakis-dodecyl-peri-hexabenzocoronene (HBC-C12) adsorbed on a template monolayer (n-C50H102). STM measurements at the liquid/solid interface made it possible to follow in real time the early stage of deposition of the HBC-C12 molecules. Additionally, molecule manipulations were realized using the tip of the STM. Our measurements give direct evidence of two successive phase transitions occurring in the upper HBC monolayer weakly bonded to the underlying template layer.
Among the gastropods, some muricid shells are composed of an inner aragonitic crossed lamellar layer and a calcitic prismatic outer layer. The analysis of the structure and composition of the two layers of Concholepas shows that the crossed lamellar layer is similar to those of other Mollusc taxa. Sr, Mg and S contents are low in both layers. According to infrared spectrometry, the organic content of the outer calcitic layer is higher than that of the aragonitic crossed lamellar layer. The study of the nanostructure allows for the proposal of a new 3D interpretation of the fine structure of the crossed lamellar layer. The calcitic prismatic layer is compared with the outer calcitic prismatic layer of an archaeogastropod genus: Haliotis.
Rapid and sensitive assays for plasmin, plasminogen and plasminogen activators (PA) were developed and applied to bovine milk. The reaction medium was clarified by addition of a dissolving agent after hydrolysis of a fluorescent substrate specific for plasmin. This final step enabled the use of larger sample amount with higher substrate concentration than other methods, and avoided previous sample preparation. The use of 4 g gelatin/l in buffers preserved plasmin activity, thus avoiding risks of overestimation of the assays results. Sensitivity, detection level, repeatability and analysis run time of plasmin and plasminogen assay were improved over previous enzymatic methods with synthetic substrates. The PA assay was assessed by measuring conversion of exogenous plasminogen into plasmin. A new kinetic approach was used to enable the direct determination of global PA activities on raw milk samples without interference from indigenous plasmin.
This present case report describes two siblings with severe type V hyperlipoproteinaemia, diagnosed very early in life and due to the combination of the common apolipoprotein (Apo) E2 allele and a rare mutant variant of ApoE, ApoE3 (Arg 136 → Ser). Phenotyping of ApoE falsely identified E2/E2 phenotype. The presence of mutated ApoE was suspected on an unusual restriction polymorphism of a Hha 1 restriction site and confirmed by sequence analysis of the cloned polymerase chain reaction fragment of exon 4 and familial segregation study. The severity of the hypertriacylglycerolaemia was modulated by the lipid content of the diet. A low-fat diet enriched in medium-chain triacylglycerol (TAG) decreased but did not normalize plasma TAG levels in both affected patients of the pedigree. A standardized lipid-enriched test meal showed a marked impairment of TAG-rich lipoprotein (TRL) clearance, especially the exogeneous TRL bearing ApoB-48 which still represented 79 % of total TRL 7 h after the fat load. Finally, differences between the male and female siblings with the existence of a consanguine relationship in their parents suggested the involvement of other genetic factors in modulating the severity of phenotypic expression. This observation reinforces the usefulness of genotyping of ApoE for the characterization of genetic hypertriacylglycerolaemia and selection of the appropriate diet and treatment.
Since nineteenth century naturalists identified salinity as a major determinant of diatom distribution, the remains of these organisms have become popular paleoenvironmental indicators for coastal deposits. A variety of problems in coastal geology were tackled using diatom-based methods, covering fields such as stratigraphy, the study of coastal processes, paleogeography, sea-level and climate change, tectonics, natural hazard assessment and archeology. This review highlights some of the major prospects and problems of paleoenvironmental diatom research on former depositional environments and sedimentation conditions in the coastal zone, as well as its contribution to the study of relative sea-level change and other processes affecting coastal genesis. For several reasons, e.g., the early recognition of important sea-level variations and coastline changes relating to glacial/interglacial cycles, the projected impact of possible future sea-level rise on coastal lowlands, the comparability of the fossil biotic record to contemporaneous observations, and the development of high-resolution dating methods – such research has focused mainly on the Quaternary and the Holocene in particular. Relatively few studies reached further back in time (e.g., Burckle & Akiba, 1978; Harwood, 1986; Pickard et al., 1986; Tawfik & Krebs, 1995). This account therefore also deals primarily with the most recent geological time window, where techniques and applications are most refined. Intended as a brief introduction only, completeness is not attempted. Some closely related topics, such as the ecology of marine–littoral diatoms, salinity calibration, estuarine settings and archeological contexts are treated more in detail elsewhere in this volume.
In order to optimize the use of caseins as surfactants, the surface tension, foaming capacity and stability were measured as a function of pH, ionic strength, protein concentration and polarity (modified by covalent binding of carbohydrates). We found that the caseins differ in their behaviour at the air/water interface with β-casein showing the greatest ability to decrease surface tension and to produce foams, due probably to its amphipathic structure. In experiments carried out at pH values close to pI, with low ionic strength and constant solubility (optimal conditions for foam formation), we observed a high surface hydrophobicity, a good accessibility and flexibility of peptidic side chains (evaluated by proteolysis), and a high foaming capacity parallelled by increased surface pressure. Foam stability of caseins was low compared to those of globular proteins such as β lactoglobulin.
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