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In recent years an enhanced catabolism of serine, with or without the existence of porphyria, has been demonstrated in relation to a specific subtype of psychosis, according to ICD-10 criteria, the acute polymorphic psychosis with or without symptoms of schizophrenia. Since sensory perceptual distortions play a key role in the symptomatology, patients with this disorder are referred to as Acute Polymorphic Psychosis plus psychosensory phenomena (APP+). In a retrospective study, including a total of 140 chronic psychiatric patients, we investigated the prevalence of Acute Intermittent Porphyria (AIP) and APP+. No subjects with AIP were found. In two patients APP+ could be demonstrated, based on both clinical characteristics and positive biochemical markers, ie lowered plasma serine concentration and increased TSM-ratio (100 × Taurine (μmol/l)/Serine concentration * Methionine concentration). In three patients the psychotic disorder was suspected to be present. It is concluded that careful psychiatric diagnosing may reveal specific psychotic disorders with a distinct biological pathogenetic factor, ie a disturbed serine metabolism.
Two varieties of bahiagrass were evaluated under Florida conditions for forage tolerance to the new herbicide, aminocyclopyrachlor (ACP), which is essential for product development decisions. Herbicide treatments included ACP alone at 70 and 140 g ai ha−1, ACP + chlorsulfuron at 69 + 27 and 138 + 54 g ai ha−1, ACP + 2,4-D amine at 70 + 532 g ai ha−1 and 140 + 1,064 g ai ha−1, ACP + triclopyr-amine at 70 + 140 g ai ha−1 and 140 + 280 g ai ha−1, and ACP + metsulfuron at 46 + 7, 78 + 12, and 168 + 26 g ai ha−1, and also included a nontreated check. ‘Argentine’ bahiagrass was the most tolerant forage species, and ‘Pensacola’ bahiagrass was sensitive to ACP + metsulfuron and initially to ACP + chlorsulfuron. Herbicide applications using ACP, when labeled, will likely provide good to excellent control of several weed species, with little long-term impact on bahiagrass forage production when the cultivar is known.
This work presents the first results of a study about possible effects on the surface temperature during short periods of lower fluxes of Galactic Cosmic Rays at Earth, called Forbush Decreases. There is a hypothesis that the Galactic Cosmic Ray flux decreases cause changes on the physical-chemical properties of the atmosphere. We have conducted a study to investigate these possible effects on several latitudinal regions, around the ten strongest FDs occurred from 1987 to 2015. We have found a possible increase on the surface temperature at middle and high latitudes during the occurence of these events.
The tolerance of bermudagrass and stargrass to the relatively new herbicide, aminocyclopyrachlor (ACP), must be known before it can be recommended for weed control in these forage systems. Field experiments were conducted in 2012 and 2013 in south-central Florida to determine the tolerance of established bermudagrass and stargrass to various rates and combinations of ACP, chlorsulfuron, 2,4-D, triclopyr, and metsulfuron. Overall, bermudagrass and stargrass injury was transient and was minimal by 60 d after treatment (DAT). Similarly, biomass production was negatively affected at 30 DAT when treated with ACP at rates of 70 g ae ha−1 or greater, but was similar to the nontreated control by 60 DAT. Tank-mixing ACP with chlorsulfuron, 2,4-D amine, triclopyr, or metsulfuron did not increase injury compared with ACP alone applied at equivalent rates. Forage nutritive values were unaffected by herbicides. These data suggest that long-term effects of ACP on bermudagrass and stargrass are negligible, and this herbicide could be an important component of weed management programs in these forage systems.
Studies under Florida conditions for susceptibility of pasture weed species to the new herbicide, aminocyclopyrachlor (ACP), are essential. Sensitivity of weed species was dependent upon the species and environment. Whitehead broom was not susceptible to ACP. Dogfennel control was consistently above 85% 1 yr after treatment with ACP at 140 g ha−1 and all ACP premixes. Milkpea was initially sensitive to all ACP treatments, but regrowth was evident in all treatments after 1 yr at one location. All ACP treatments resulted in 100% control of tropical soda apple 1 yr after treatment at one location, but less than 50% control at a second location. Herbicide applications with ACP, when labeled, will likely provide good to excellent control (80 to 100%) of several weed species.
Remingtonocetidae are Eocene archaeocetes that represent a unique experiment in cetacean evolution. They possess long narrow skulls, long necks, fused sacra, and robust hind limbs. Previously described remingtonocetids are known from middle Eocene Lutetian strata in Pakistan and India. Here we describe a new remingtonocetid, Rayanistes afer, n. gen. n. sp., recovered from a middle to late Lutetian interval of the Midawara Formation in Egypt. The holotype preserves a sacrum with four vertebral centra; several lumbar and caudal vertebrae; an innominate with a complete ilium, ischium, and acetabulum; and a nearly complete femur. The ilium and ischium of Rayanistes are bladelike, rising sharply from the body of the innominate anterior and posterior to the acetabulum, and the acetabular notch is narrow. These features are diagnostic of Remingtonocetidae, but their development also shows that Rayanistes had a specialized mode of locomotion. The expanded ischium is larger than that of any other archaeocete, supporting musculature for powerful retraction of the hind limbs during swimming. Posteriorly angled neural spines on lumbar vertebrae and other features indicate increased passive flexibility of the lumbus. Rayanistes probably used its enhanced lumbar flexibility to increase the length of the power stroke during pelvic paddling. Recovery of a remingtonocetid in Egypt broadens the distribution of Remingtonocetidae and shows that protocetids were not the only semiaquatic archaeocetes capable of dispersal across the southern Tethys Sea.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
We have achieved a drastic improvement of the performance as thin film transistor (TFT) for solution-processed IGZO thin film by controlling drying temperature of solvents containing the precursor solution. The IGZO-precursor solution was prepared by mixing of metal nitrates and two kinds of organic solvents, 2-methoxyethanol (2ME) and 2,2,2-trifluoroethanol (TFE). 2ME was used for dissolving metal nitrates. TFE was added as a solvent for reducing surface tension as small as possible, leading to improvement of the wettability of the precursor solution on the surface of the substrate. In order to discuss the relationship between morphology and drying process, the spin-coated IGZO-precursor films were dried at room temperature and 140 °C on a hotplate, respectively. Annealing of the both films was carried out at 300 °C in an electric oven for 60 min after each drying process. Drying at room temperature provides a discontinuous film, resulting in a large variation of the TFT performance. On the other hand, drying at 140 °C provides a continuous film, resulting in the higher TFT performance and a minor variation. The difference in surface morphologies would be derived from the evaporation rate of the organic solvents. The rapid evaporation at 140 °C brings about rapid pinning of the spin-coated precursor layer on the substrate. Preparation process via the drying at 140 °C gave ∼ 1 cm2 V-1 s-1 of the saturated mobility, quite small hysteresis, and 107∼ 108 of the on-off ratio.
SPHERE, the Spectro-Polarimetric High-contrast Exoplanet REsearch instrument for the VLT
is optimized towards reaching the highest contrast in a limited field of view and at short
distances from the central star, thanks to an extreme AO system. SPHERE is very well
suited to study the close environment of Betelgeuse, and has a strong potential for
detecting the ejection activity around this key red supergiant.
We present long term site testing statistics based on DIMM and GSM data obtained at Dome C, Antarctica. These data have been collected on the bright star Canopus since the end of 2003. We give values of the integrated turbulence parameters in the visible (wavelength 500 nm). The median value we obtained for the seeing are 1.2 arcsec, 2.0 arcsec and 0.8 arcsec at respective elevations of 8m, 3m and 20m above the ground. The isoplanatic angle median value is 4.0 arcsec and the median outer scale is 7.5m. We found that both the seeing and the isoplanatic angle exhibit a strong dependence with the season (the seeing is larger in winter while the isoplanatic angle is smaller).
The ASTEP project aims at detecting and characterizing transiting planets from Dome C, Antarctica, and qualifying this site for photometry in the visible. The first phase of the project, ASTEP South, is a fixed 10 cm diameter instrument pointing continuously towards the celestial South Pole. Observations were made almost continuously during 4 winters, from 2008 to 2011. The point-to-point RMS of 1-day photometric lightcurves can be explained by a combination of expected statistical noises, dominated by the photon noise up to magnitude 14. This RMS is large, from 2.5 mmag at R = 8 to 6% at R = 14, because of the small size of ASTEP South and the short exposure time (30 s). Statistical noises should be considerably reduced using the large amount of collected data. A 9.9-day period eclipsing binary is detected, with a magnitude R = 9.85. The 2-season lightcurve folded in phase and binned into 1,000 points has a RMS of 1.09 mmag, for an expected photon noise of 0.29 mmag. The use of the 4 seasons of data with a better detrending algorithm should yield a sub-millimagnitude precision for this folded lightcurve. Radial velocity follow-up observations reveal a F-M binary system. The detection of this 9.9-day period system with a small instrument such as ASTEP South and the precision of the folded lightcurve show the quality of Dome C for continuous photometric observations, and its potential for the detection of planets with orbital periods longer than those usually detected from the ground.
ASTEP (Antarctic Search for Transiting Exo Planets) is a research program funded mainly by French ANR grants and by the French Polar Institute (IPEV), dedicated to the photometric study of exoplanetary transits from Antarctica.
The preliminary “pathfinder” instrument ASTEP–South is described in another communication (Crouzet et al., these proceedings), and we focus in this presentation on the main instrument of the ASTEP program: “ASTEP–400”, a 40 cm robotized and thermally-controlled photometric telescope operated from the French-Italian Concordia station (Dome C, Antarctica).
ASTEP–400 has been installed at Concordia during the 2009-2010 summer campaign. Since, the telescope has been operated in nominal conditions during 2010 and 2011 winters, and the 2012 winterover is presently in progress. Data from the first two winter campaigns are available and processed. We give a description of the ASTEP–400 telescope from the mechanical, optical and thermal point of view. Control and software issues are also addressed. We end with a discussion of some astronomical results obtained with ASTEP–400.
Indoor radon surveys were carried out in some of the Arab
countries through a Coordination Research Program (CRP) organized
by the Arab Atomic Energy Agency (AAEA). The objectives of the program
aim at establishing a database on indoor radon concentration levels
in the region and investigating any anomalies, where they exist.
The approach adopted by the survey teams to achieve public participation
in accepting the radon detectors in dwellings is presented and discussed.
Most of the participants in the CRP used the passive method (CR-39
plastic detectors) for long-term radon measurements, while others
used charcoal detectors and E-Perm systems for short-term measurements.
The results of the surveys showed that radon concentration levels
in most of the dwellings were low, whilst in some old cities and
in an area close to a phosphate mine the levels were found to be
A channel layer substitution of a wider bandgap AlGaN for a conventional GaN in high electron mobility transistors (HEMTs) is an effective method of enhancing the breakdown voltage. Wider bandgap AlGaN, however, should also increase the ohmic contact resistance. Si ion implantation doping technique was utilized to achieve sufficiently low resistive source/drain contacts. The fabricated AlGaN channel HEMTs with the field plate structure demonstrated good pinch-off operation with sufficiently high drain current density of 0.5 A/mm without noticeable current collapse. The obtained maximum breakdown voltages was 1700 V in the AlGaN channel HEMT with the gate-drain distance of 10 μm. These remarkable results indicate that AlGaN channel HEMTs could become future strong candidates for not only high-frequency devices such as low noise amplifiers but also high-power devices such as switching applications.
To explore competitive or cooperative effects novel organic-inorganic hybrid copolymers are being prepared and studied. The use of polyhedral oligomeric silsesquioxanes (POSS), a molecularly precise isotropic comonomer, is being utilized to take advantage of the inherent size scale of these particles, average diameters of 1-2 nm. The organic component selected for study in these hybrid systems are either semi-crystalline or amorphous polymers. The architectures of the hybrid copolymers range from random, to precise block copolymers, as well as telechelic and hemi-telechelic end-functionalized model compounds. The degree of POSS aggregation that occurs is found to be a function of thermal history, and processing conditions. Templating, or arresting, aggregation can be achieved using either crystalline organic polymer scaffolds in the bulk. The second inorganic comonomers for study has been constructed from icosahedral carboranes. Dicarbo-closo-decaboranes have been widely investigated for their thermal stability, chemical resistance, unique geometry, and the high cross-section for the capture of thermal neutrons. While carboranes have been widely incorporated into small molecules, metal complexes, and on a limited basis in polymer systems relatively little work exists relating their unique properties to systems with extended π-conjugation. Details of the syntheses, characterization and performance properties of both sets of hybrid systems will be discussed.
Cobalt hydroxide thin films with a thickness of 100 nm were deposited onto glass, Si and indium tin oxide (ITO)-coated glass substrates by reactively sputtering a Co target in H2O gas. The substrate temperature was varied from -20 to +200°C. The EC performance of the films was investigated in 0.1 M KOH aqueous solution. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy of the samples indicated that Co3O4 films were formed at substrate temperatures above 100°C, and amorphous CoOOH films were deposited in the range from 10 to -20°C. A large change in transmittance of approximately 26% and high EC coloration efficiency of 47 cm2/C were obtained at a wavelength of 600 nm for the CoOOH thin film deposited at -20°C. The good EC performance of the CoOOH films is attributed to the low film density and amorphous structure.
ASTEP South is an Antarctic Search for Transiting ExoPlanets in the South pole field, from the Concordia station, Dome C, Antarctica. The instrument consists of a thermalized 10 cm refractor observing a fixed 3.88° × 3.88° field of view to perform photometry of several thousand stars at visible wavelengths (700–900 nm). The first winter campaign in 2008 led to the retrieval of nearly 1600 hours of data. We derive the fraction of photometric nights by measuring the number of detectable stars in the field. The method is sensitive to the presence of small cirrus clouds which are invisible to the naked eye. The fraction of night-time for which at least 50% of the stars are detected is 74% from June to September 2008. Most of the lost time (18.5% out of 26%) is due to periods of bad weather conditions lasting for a few days (“white outs”). Extended periods of clear weather exist. For example, between July 10 and August 10, 2008, the total fraction of time (day+night) for which photometric observations were possible was 60%. This confirms the very high quality of Dome C for nearly continuous photometric observations during the Antarctic winter.
Images in visible interferometry are characterised by their low coherence time, and except for brightest stars, the flux on the detector is much less than one photon per pixel per image. Algol and Comptage de Photons Nouvelle Génération (CPNG) are new photon counting cameras developed for high angular resolution in the visible. They are intensified CCDs built to benefit from improvements in photonic commercial components, and personal computer processing power. We present how we achieve optimal performances (sensitivity and spatiotemporal resolution) by the combination of proper optical and electronics design, and real-time elaborated data processing. The number of pixels is 532 × 516 and 768 × 640 read at a frame rate of 262 Hz and 50 Hz for CPNG and Algol respectively. The dark current is very low: 5 × 10-4 electron.pixel-1.s-1. Quantum efficiencies reach up to 36% in the visible with the GaAsP photocathodes and and 26% in the red with the GaAs ones, thanks to the sensitivity of the photocathodes and to the photon centroiding algorithm; they are likely the highest values reported for ICCDs.