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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.
The presence of salt in dilatant normal faults may have a strong influence on fault mechanics in the Groningen field and on the related induced seismicity. At present, little is known of the structure of these fault zones. This study starts with the geological evolution of the Groningen area, where, during tectonic faulting, rock salt may have migrated downwards into dilatant faults. These fault zones therefore may contain inclusions of rock salt. Because of its rate-dependent mechanical properties, the presence of salt in a fault may introduce a loading-rate dependency into fault movement and affect the distribution of magnitudes of seismic events. We present a first-look study showing how these processes can be investigated using a combination of analogue and numerical modelling. Full scaling of the models and quantification of implications for induced seismicity in Groningen require further, more detailed studies: an understanding of fault zone structure in the Groningen field is required for improved predictions of induced seismicity. The analogue experiments are based on a simplified stratigraphy of the Groningen area, where it is generally thought that most of the Rotliegend faulting has taken place in the Jurassic, after deposition of the Zechstein. This suggests that, at the time of faulting, the sulphates were already transformed into brittle anhydrite. If these layers were sufficiently brittle to fault in a dilatant fashion, rock salt was able to flow downwards into the dilatant fractures. To test this hypothesis, we use sandbox experiments where we combine cohesive powder as analogue for brittle anhydrites and carbonates with viscous salt analogues to explore the developing fault geometry and the resulting distribution of salt in the faults. Using the observations from analogue models as input, numerical models investigate the stick-slip behaviour of fault zones containing ductile material qualitatively with the discrete element method (DEM). Results show that the DEM approach is suitable for modelling the seismicity of faults containing salt. The stick-slip motion of the fault becomes dependent on shear loading rate with a modification of the frequency–magnitude distribution of the generated seismic events.
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.
The transport equation for the mean turbulent energy dissipation rate
along the centreline of a fully developed channel flow is derived by applying the limit at small separations to the two-point budget equation. Since the ratio of the isotropic energy dissipation rate to the mean turbulent energy dissipation rate
is sufficiently close to 1 on the centreline, our main focus is on the isotropic form of the transport equation. It is found that the imbalance between the production of
due to vortex stretching and the destruction of
caused by the action of viscosity is governed by the diffusion of
by the wall-normal velocity fluctuation. This imbalance is intrinsically different from the advection-driven imbalance in decaying-type flows, such as grid turbulence, jets and wakes. In effect, the different types of imbalance represent different constraints on the relation between the skewness of the longitudinal velocity derivative
and the destruction coefficient
of enstrophy in different flows, thus resulting in non-universal approaches of
towards a constant value as the Taylor microscale Reynolds number,
, increases. For example, the approach is slower for the measured values of
along either the channel or pipe centreline than along the axis in the self-preserving region of a round jet. The data for
collected in different flows strongly suggest that, in each flow, the magnitude of
is bounded, the value being slightly larger than 0.5.
Studies of the relationship between obesity and chronic kidney disease (CKD) in nationally representative population samples are limited. Our study aimed to determine if overweight and obesity were independently associated with the risk for CKD in the 2010 Health Survey for England (HSE).
The HSE is an annually conducted cross-sectional study. In 2010 serum creatinine was included to determine the incidence of CKD in the population. CKD was defined as estimated glomerular filtration rate (eGFR) <60 ml/min per 1·73 m2 using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. Multivariable logistic regression models were developed to calculate odds ratios and 95 % confidence intervals for CKD risk by BMI (reference category: BMI=18·5–24·9 kg/m2) and adjusted for age, gender, ethnicity, smoking, diabetes and hypertension.
A random sample of nationally representative households in England.
Adults (n 3463) with calculable eGFR and BMI were included.
The prevalence of CKD was 5·9 %. The risk of CKD was over 2·5 times higher in obese participants compared with normal-weight participants in the fully adjusted model (BMI=30·0–39·9 kg/m2: adjusted OR=2·78 (95 % CI 1·75, 4·43); BMI ≥ 40·0 kg/m2: adjusted OR=2·68 (95 % CI 1·05, 6·85)).
Obesity is associated with an increased risk of CKD in a national sample of the UK population, even after adjustment for known CKD risk factors, which may have implications for CKD screening and future national health service planning and delivery.
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.
A high occurrence rate of consanguineous marriages may favour the onset and increased frequency of autosomal recessive diseases in a population. The population of Monte Santo, Bahia, Brazil, has a high frequency of rare genetic diseases such as mucopolysaccharidosis type VI, whose observed frequency in this population is 1:5000, while the incidence of this disease recorded in other regions of the world varies from 1:43,261 in Turkey to 1:1,505,160 in Switzerland. To verify the influence of consanguineous marriage on the increased frequency of observed genetic diseases in this population, the population structure and frequency of different types of marriage during different time periods were evaluated. A total of 9765 marriages were found in an analysis of parish marriage records from the city. Over three periods, 1860–1895, 1950–1961 and 1975–2010, the inbreeding rates were 37.1%, 13.2% and 4.2% respectively. Although there was a high rate of inbreeding, endogamic marriages were the dominant marriage type in all three periods. In the most recent period, there was an increase in the number of exogamous marriages and those among immigrants, but most of these occurred among individuals from cities that neighbour Monte Santo. The low rate of migration and high frequency of endogamic and consanguineous marriages show that growth of this population is predominantly internal and could explain the occurrence, and increase in frequency, of recessive genetic diseases in the city.
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.
The Dome C high plateau is unique for coronagraphic observations: sky brightness is reduced, water vapour is low, seeing is excellent and continuity of observations on several weeks is possible. ESCAPE (the Extreme Solar Coronagraphy Antarctic Program Experiment) will perform 2-dimensional spectroscopy of the forbidden line of FeXIV at 530.285 nm: precise line profile analysis will allow the diagnostic of the nature of waves by simultaneous measurements of velocities and intensities in the corona. ESCAPE is proposed to Institut Paul-Emile Victor (IPEV) for a campaign in 2012–2013 at Dome C/Concordia since all subsystems are available in particular thanks to an ESA STARTIGER 2010 R&D “Toward a New Generation of Formation Flying Coronagraph”. Using state-of-the-art technologies developed for Space missions (a Three Mirrors Anastigmat telescope, the TMA, a 4 stages Liquid Crystal Tunable-filter Polarimeter, the LCTP) allows us to propose an automated Coronal Green Line full-field Polarimeter for unique observations (waves nature and intensity to address coronal heating) with the best possible performances on Earth and for preparing and testing the technologies for the next steps in Space. No other site would allow such coronagraphic performances (the sky brightness is a factor 2 to 4 better than in Hawaï) and with high spatial resolution (better than an arcsec is possible).
Site studies have proved Dome C to be an excellent site for optical interferometry, maybe the only possible site on Earth for the deployement of a large post-VLTI interferometric facility, like KEOPS. Indeed, recent studies have shown the possiblity of interferometric observations of faint objects, high sensitivity and high precision observations, direct imaging and nulling interferometry. However the achievement of this ambitious project assumes the pavement of a roadmap, including different steps. The first one should be a demonstrator, called Mykerinos. Mykerinos is a diluted aperture interferometer composed of at least two light collecting units with a baseline between 40 to 100 m (or more) consisting of 50 cm diameter telescopes. The telescope design is directly derived from our Laboratory's experience in the ASTEP experiment. Mykerinos will be equipped with a dual field focal instrument which is a pre-requisite for its site testing, as well as for its science demonstration purposes.
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.
Growth hormone (GH) affects linear growth and body composition, by increasing the secretion of insulin-like growth factor-I (IGF-I), muscle protein synthesis and lipolysis. The intake of protein (PROT) as well as the specific amino acids arginine (ARG) and lysine (LYS) stimulates GH/IGF-I secretion. The present paper aimed to investigate associations between PROT intake as well as intake of the specific amino acids ARG and LYS, and subsequent 3-year-change in linear growth and body composition among 6-year-old children.
Children’s data were collected from Copenhagen (Denmark), during 2001–2002, and again 3 years later. Boys and girls were separated into normal weight and overweight, based on BMI quintiles. Fat-free mass index (FFMI) and fat mass index (FMI) were calculated. Associations between change (Δ) in height, FMI and FFMI, respectively, and habitual PROT intake as well as ARG and LYS were analysed by multiple linear regressions, adjusted for baseline height, FMI or FFMI and energy intake, age, physical activity and socio-economic status.
Eighteen schools in two suburban communities in the Copenhagen (Denmark) area participated in the study.
In all, 223 children’s data were collected for the present study.
High ARG intake was associated with linear growth (β = 1·09 (se 0·54), P = 0·05) among girls. Furthermore, in girls, ΔFMI had a stronger inverse association with high ARG intake, if it was combined with high LYS intake, instead of low LYS intake (P = 0·03). No associations were found in boys.
In prepubertal girls, linear growth may be influenced by habitual ARG intake and body fat gain may be relatively prevented over time by the intake of the amino acids ARG and LYS.
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.
ASTEP South is the first phase of the ASTEP project that aims to determine the quality of Dome C as a site for future photometric searches for transiting exoplanets and discover extrasolar planets from the Concordia base in Antarctica. ASTEP South consists of a front-illuminated 4k × 4k CCD camera, a 10 cm refractor, and a simple mount in a thermalized enclosure. A double-glass window is used to reduce temperature variations and the associated turbulence on the optical path. The telescope is fixed and observes a 4° × 4° field of view centered on the celestial South pole. With this design, A STEP South is very stable and observes with low and constant airmass, both being important issues for photometric precision. We present the project, we show that enough stars are present in our field of view to allow the detection of one to a few transiting giant planets, and that the photometric precision of the instrument should be a few mmag for stars brighter than magnitude 12 and better than 10 mmag for stars of magnitude 14 or less.
We have already reported that Au or B doped SiGe amorphous thin films have superior thermoelectric properties which are attribute to amorphous phase. For the practical use, the bulk materials are required. In this work, we have tried and succeeded to fabricate Si-Ge-B amorphous bulk samples. First, fine particles were prepared by three kinds of mechanical process, such as roller milling method, mechanical alloying method and planetary milling method. It was intended to introduce a large amount of defects and strain into samples and/or gamorphouslization'h. Then, the prepared fine particles were pressed and formed into 2 x 5 x 15 mm^3 samples. Thermoelectric power and electrical resistivity of samples were measured by steady state measurement and four terminal method with temperature range of room temperature to 873 K in N2 flow at atmosphere pressure, respectively. Thermal conductivity was measured by photo-pyroelectric method in room temperature. Some samples have maximum value of thermoelectric power over 10-3 V/K. therefore≤ we were succeeded to prepare bulk materials which have higher thermoelectric power than that of conventional crystal materials. X-ray diffraction measurement and scanning electron microscope observation were performed on fabricated samples. From XRD measurement and SEM observation, the samples were in mixed condition of disordered microcrystals and amorphous state.
Objective: To review methods for evaluating iodine deficiency in pregnant women and young infants and to discuss factors to be considered in the interpretation of their results.
Design: Review of the literature regarding the various methods available for assessing iodine status.
Setting: Population surveys and research studies.
Subjects: Pregnant women and young infants.
Results: Several factors to consider when assessing iodine status in pregnant women and young infants include: 1) the urinary iodine (UI) concentration (μg l-1) is not interchangeable with 24 h UI excretion (μg per 24 h); 2) the concentration of iodine in a spot or casual urine sample cannot be used to diagnose iodine deficiency in an individual; 3) a moderate fall in the concentration of serum free T4 during pregnancy is not a sign of maternal iodine deficiency; 4) an increase in the concentration of serum thyroglobulin (Tg) during pregnancy is not a sign of maternal iodine deficiency; 5) a higher concentration of TSH and Tg in cord blood than in maternal blood is not a sign of iodine deficiency in the mother or neonate; and 6) thyroid function in a full-term foetus, a neonate or a small child is not more sensitive to a mild iodine deficiency than in the mother.
Conclusions: If the iodine status of pregnant women and small children is not to be misjudged, the above six factors need to be taken into account.
We present the results of the first light of CORONA obtained during the summer campaign 2005 at Dome C. The CORONA experiment uses an automated 14'' antarctized telescope for its remote
operation from the Concordia station. The instrument includes an Achromatized Phase Knife
Coronagraph (APKC) with no tip-tilt correction. The high contrast long exposure is obtained
from image selection among raw short exposures.