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Poor impulse control is a common feature in patients with Parkinson's disease (PD). However, before testing whether patients with PD and controls differ in impulsivity, one must assess whether impulsivity measures are invariant across groups. Consequently, we examined (a) the measurement and structural invariance of a scale assessing changes in four dimensions of impulsivity (urgency, lack of premeditation, lack of perseverance and sensation seeking) among patients with PD and controls; and (b) whether the four impulsivity traits relate differentially to risky decisions by patients.
Close relatives of 78 patients with idiopathic PD and 96 control participants were given the short Urgency–Premeditation–Perseverance–Sensation seeking Impulsive Behaviour Scale (UPPS), which assesses changes in four dimensions of impulsivity. Participants also completed the Game of Dice Task (GDT), a laboratory measure of risk taking.
Multigroup confirmatory factor analyses supported measurement invariance across groups, whereas structural invariance was not confirmed. Patients with PD showed greater variability and higher impulsivity than controls. Furthermore, patients with impulse control disorders (ICDs) demonstrated even greater levels of sensation seeking than patients without ICDs. Finally, lower premeditation and greater perseverance were significantly associated with greater risk taking in patients with PD, and higher agonist dopaminergic doses with less risky choices on the GDT.
The questionnaire appears to function comparably across patients and controls. Thus, group comparisons on the questionnaire can be considered valid. Mean differences between groups on the dimensions of impulsivity may reflect executive impairments and/or abnormal reward processing in patients with PD, which may lead to risky behaviours.
From its position at the heart of the Cinémathèque française in Paris, the Bibliothèque du film provides all sorts of users with a unique documentary collection on the cinema: monographs, journals, posters, drawings, photographs, archives and videos. The reading rooms, the vidéothèque, the image library and the archive search room allow users to consult all these documents.
Since 1991, in France, studies on the conditioning of iodine were carried out to assess the potential of several specific inorganic host matrices. The apatite family has been mainly studied because of its good chemical durability and its ability to confine iodine over geological time scales. A lead-bearing apatite, Pb10(VO4)4.8(PO4)1.2I2, and a calcium-bearing apatite, Ca10(PO4)6(OH)2-x(IO3)x, were selected on the basis of their incorporation rate (between 7 and 10 wt.%) and a satisfactory resistance to leaching (V0(50 °C, pure water) ∼ 10-2 g.m-2.d-1; Vr(50 °C, pure water) < 10-4 g.m-2.d-1). However, with such materials, the removal of open porosity requires non conventional sintering techniques like spark plasma sintering to decrease the surface exposed to water. This is why, in parallel, other matrices, like silver phosphate glasses, have also been investigated. To improve the chemical durability and thermal properties of these glasses, cross-linking reagents were added to their formulation.
Having described the countries of the “numerous peoples of the Slavs,” the late twelfth-century chronicler Helmold of Bosau added, “If you consider Hungary as a part of Slavania, as some would suggest, because it does not differ by customs or by language, the area of the Slavic language extends so far that a proper estimate is quite lacking.” These few words indicate how clearly local the chronicler's horizon was—the farther away from Wagria, the fuzzier his information. At the same time, though, Helmold made plain that the Slavic language was for him an essential element of what Slavania was. As a parish priest at the forefront of missionary and settlement activities, Helmold wrote a chronicle that is a unique source of information for intercultural interactions between Germans and Slavs during the high medieval colonization period.
The picosecond ultrasonics technique is used to investigate the viscoelastic properties of nucleus of fixed single osteoblast progenitor cells adhering on a titanium alloy substrate. A two-color probing picosecond ultrasonics and a fluorescence visualization setups were developed and combined to allow to distinguish subcomponents inside the cell under investigation. It opens the way for quantitative measurements of the viscoelastic properties of single cells and of their sub-micrometer thickness. It is shown that a blue probe, λ = 400 nm, is preferable to a red probe, λ = 800 nm, to perform these measurements with fixed sub-micrometer bone cells. 26 GHz acoustic frequencies are detected in cells as thin as 135 nm. A 1D analytical model of the acoustic generation and of the optical detection is used to describe the experimental results. The nucleus longitudinal elastic moduli (13–16 GPa) and dynamic viscosities (13–30 cP) are measured at high frequencies (GHz) from a time-frequency analysis of the experimental data of fixed single cells.
Equip the edges of the lattice ℤ2 with i.i.d. random capacities. A law of
large numbers is known for the maximal flow crossing a rectangle in ℝ2 when the
side lengths of the rectangle go to infinity. We prove that the lower large deviations are
of surface order, and we prove the corresponding large deviation principle from below.
This extends and improves previous large deviations results of Grimmett and Kesten  obtained for boxes of particular orientation.
A high resolution analysis of benthic foraminifera as well as of aeolian terrigenous proxies extracted from a 37 m-long marine core located off the Mauritanian margin spanning the last ~ 1.2 Ma, documents the possible link between major continental environmental changes with a shift in the isotopic signature of deep waters around 1.0–0.9 Ma, within the so-called Mid-Pleistocene Transition (MPT) time period. The increase in the oxygen isotopic composition of deep waters, as seen through the benthic foraminifera δ18O values, is consistent with the growth of larger ice sheets known to have occurred during this transition. Deep-water mass δ13C changes, also estimated from benthic foraminifera, show a strong depletion for the same time interval. This drastic change in δ13C values is concomitant with a worldwide 0.3‰ decrease observed in the major deep oceanic waters for the MPT time period. The phase relationship between aeolian terrigeneous signal increase and this δ13C decrease in our record, as well as in other paleorecords, supports the hypothesis of a global aridification amongst others processes to explain the deep-water masses isotopic signature changes during the MPT. In any case, the isotopic shifts imply major changes in the end-member δ18O and δ13C values of deep waters.
Previous studies have suggested that Marine Isotope Stage (MIS) 13, recognized as atypical in many paleoclimate records, is marked by the development of anomalously strong summer monsoons in the northern tropical areas. To test this hypothesis, we performed a multi-proxy study on three marine records from the tropical Indian Ocean in order to reconstruct and analyse changes in the summer Indian monsoon winds and precipitations during MIS 13. Our data confirm the existence of a low-salinity event during MIS 13 in the equatorial Indian Ocean but we argue that this event should not be considered as “atypical”. Taking only into account a smaller precession does not make it possible to explain such precipitation episode. However, when considering also the larger obliquity in a more complete orbitally driven monsoon “model,” one can successfully explain this event. In addition, our data suggest that intense summer monsoon winds, although not atypical in strength, prevailed during MIS 13 in the western Arabian Sea. These strong monsoon winds, transporting important moisture, together with the effect of insolation and Eurasian ice sheet, are likely one of the factors responsible for the intense monsoon precipitation signal recorded in China loess, as suggested by model simulations.
Low levels of arsenic contamination have been previously reported (∼0.01%) in CBE grown InP by different groups. The level of As incorporation in InP is usually enhanced when arsenide(InGaAs, InAsP) / InP heterostructures are grown.
In this work, optimal growth conditions to minimize the non-intentional As contamination during the growth of these heterostructures are discussed. The red shift of band-edge excitons in the low temperature photoluminescence spectra as well as the analysis of high resolution X-ray diffraction patterns of InAsP/InP multi-quantum wells suggest the presence of As in InP barriers. This contamination is consistent with the ratio of As/P partial pressure (As residual in the chamber: 10-9-10-8 Torr) and the As/P incorporation rates. We have studied the influence of the growth temperature, the group-V/III flux ratio and the growth rate on the level of the As incorporation.
Phosphorus exposed GaAs (100) surfaces during a Chemical Beam Epitaxy growth process are studied using in-situ Reflection High Energy Electron Diffraction and ex-situ High Resolution X-ray Diffraction. It is shown that the phosphorus exposure of a GaAs (100) surface in the 500 – 580 °C temperature range results in the formation of one GaP monolayer.
Mutation tam38 of Paramecium tetraurelia is a nuclear recessive mutation with a pleiotropic effect on both trichocyst morphogenesis and nuclear processes. The analysis of the defective nuclear processes (micronuclear and macronuclear divisions, nuclear reorganization at autogamy) shows that these defects result from an abnormal localization of the nuclei. Phenocopies of tam38 abnormalities can be obtained by vinblastine treatment of wild-type cells at late stages of division. Taking into account the similarity between tam38 and a series of other mutations which also prevent trichocyst attachment to the cell surface and disturb nuclear divisions, the following interpretation is proposed: the absence of attached trichocyst induces structural changes in the plasma membrane or in the cortical region which disturb the normal cortical control of the localization of nuclei.
In Paramecium aurelia, syngen 4, gene ts21m, which is shown to segregate normally and independently of two other genes: ts111 and m1; is closely linked to gene ts401. The frequency of then recombination is of the order of a few per cent. Genetic analysis was carried out to confirm the genotypes of both double mutants and wild-type recombinants among F2 clones from crosses ts21m × ts401. This is the first case of linkage so far reported in P. aurelia.