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SMSS\,J114447.77-430859.3 ($z=0.83$) has been identified in the SkyMapper Southern Survey as the most luminous quasar in the last $\sim 9\,\rm Gyr$. In this paper, we report on the eROSITA/Spectrum-Roentgen-Gamma (SRG) observations of the source from the eROSITA All Sky Survey, along with presenting results from recent monitoring performed using Swift, XMM-Newton, and NuSTAR. The source shows a clear variability by factors of $\sim 10$ and $\sim 2.7$ over timescales of a year and of a few days, respectively. When fit with an absorbed power law plus high-energy cutoff, the X-ray spectra reveal a $\Gamma=2.2 \pm 0.2$ and $E_{\rm cut}=23^{+26}_{-5}\,\rm keV$. Assuming Comptonisation, we estimate a coronal optical depth and electron temperature of $\tau=2.5-5.3\, (5.2-8)$ and $kT=8-18\, (7.5-14)\,\rm keV$, respectively, for a slab (spherical) geometry. The broadband SED is successfully modelled by assuming either a standard accretion disc illuminated by a central X-ray source, or a thin disc with a slim disc emissivity profile. The former model results in a black hole mass estimate of the order of $10^{10}\,M_\odot$, slightly higher than prior optical estimates; meanwhile, the latter model suggests a lower mass. Both models suggest sub-Eddington accretion when assuming a spinning black hole, and a compact ($\sim 10\,r_{\rm g}$) X-ray corona. The measured intrinsic column density and the Eddington ratio strongly suggest the presence of an outflow driven by radiation pressure. This is also supported by variation of absorption by an order of magnitude over the period of $\sim 900\,\rm days$., Comment: Accepted for publication in MNRAS

NGC 5033 is an intriguing Seyfert galaxy because its subclassification may change with time, and because optical and submillimeter observations find that the massive black hole does not sit at the dynamical center of the galaxy, pointing to a past merger. We obtained a new optical spectrum of NGC 5033 using the 200″ Hale telescope at Palomar that clearly reveals a broad Hβ line (FWHM = 5400 ± 300 km s−1). This signals a clear view of the optical broad line region and requires Seyfert-1.5 designation. Some spectra obtained in the past suggest a Seyfert-1.9 classification, potentially signaling a variable or “changing-look” geometry. Our analysis of a 2019 Chandra spectrum of the massive black hole reveals very little obscuration, also suggesting a clean view of the central engine. However, the narrow Fe Kα emission line is measured to have an equivalent width of EW = 460 − 90 + 100 eV. This value is extremely high compared to typical values in unobscured active galactic nuclei . Indeed, the line is persistently strong in NGC 5033: the line equivalent width in a 2002 XMM-Newton snapshot is EW = 250 − 40 + 40 eV, similar to the EW = 290 − 100 + 100 eV equivalent width measured using ASCA in 1999. These results can likely be explained through a combination of an unusually high covering factor for reflection, and fluxes that are seen out of phase owing to light travel times. We examine the possibility that NGC 5033 may strengthen evidence for the X-ray Baldwin effect.

We present a new X-Ray Accretion Disk-wind Emulator (\textsc{xrade}) based on the 2.5D Monte Carlo radiative transfer code which provides a physically-motivated, self-consistent treatment of both absorption and emission from a disk-wind by computing the local ionization state and velocity field within the flow. \textsc{xrade} is then implemented through a process that combines X-ray tracing with supervised machine learning. We develop a novel emulation method consisting in training, validating, and testing the simulated disk-wind spectra into a purposely built artificial neural network. The trained emulator can generate a single synthetic spectrum for a particular parameter set in a fraction of a second, in contrast to the few hours required by a standard Monte Carlo radiative transfer pipeline. The emulator does not suffer from interpolation issues with multi-dimensional spaces that are typically faced by traditional X-ray fitting packages such as \textsc{xspec}. \textsc{xrade} will be suitable to a wide number of sources across the black-hole mass, ionizing luminosity, and accretion rate scales. As an example, we demonstrate the applicability of \textsc{xrade} to the physical interpretation of the X-ray spectra of the bright quasar PDS 456, which hosts the best-established accretion-disk wind observed to date. We anticipate that our emulation method will be an indispensable tool for the development of high-resolution theoretical models, with the necessary flexibility to be optimized for the next generation micro-calorimeters on board future missions, like \textit{XRISM/resolve} and \textit{Athena/X-IFU}. This tool can also be implemented across a wide variety of X-ray spectral models and beyond., 20 pages, 17 figures, MNRAS accepted for publication

The X-ray Integral Field Unit (X-IFU) is the high resolution X-ray spectrometer of ESA's Athena X-ray observatory. It will deliver X-ray data in the 0.2-12 keV band with an unprecedented spectral resolution of 2.5 eV up to 7 keV. During the observation of very bright X-ray sources, the X-IFU detectors will receive high photon rates. The count rate capability of the X-IFU will be improved by using the defocusing option, which will enable the observations of extremely bright sources with fluxes up to $\simeq 1$ Crab. In the defocused mode, the point spread function (PSF) of the telescope will be spread over a large number of pixels. In this case, each pixel receives a small fraction of the overall flux. Due to the energy dependence of the PSF, this mode will generate energy dependent artefacts increasing with count rate if not analysed properly. To account for the degradation of the energy resolution with pulse separation in a pixel, a grading scheme (here four grades) will be defined to affect the proper energy response to each event. This will create selection effects preventing the use of the nominal Auxiliary Response File (ARF) for all events. We present a new method for the reconstruction of the spectra obtained from observations performed with a PSF that varies as a function of energy. We apply our method to the case of the X-IFU spectra obtained during the defocused observations. We use the end-to-end SIXTE simulator to model defocused X-IFU observations. Then we estimate new ARF for each of the grades by calculating the effective area at the level of each pixel. Our method allows us to successfully reconstruct the spectra of bright sources when employed in the defocused mode, without any bias. Finally, we address how various sources of uncertainty related to our knowledge of the PSF as a function of energy affect our results., Comment: Accepted for publication in A&A

Accretion and ejection of matter in active galactic nuclei (AGN) are tightly connected phenomena and represent fundamental mechanisms regulating the growth of the central supermassive black hole and the evolution of the host galaxy. However, the exact physical processes involved are not yet fully understood. We present a high-resolution spectral analysis of a simultaneous \xmm\ and \nustar\ observation of the narrow line Seyfert 1 (NLS1) AGN 1H 1934-063, during which the X-ray flux dropped by a factor of $\sim6$ and subsequently recovered within 140 kiloseconds. By means of the time-resolved and flux-resolved X-ray spectroscopy, we discover a potentially variable warm absorber and a relatively stable ultra-fast outflow (UFO, $v_\mathrm{UFO}\sim-0.075\,c$) with a mild ionization state ($\log(\xi/\mathrm{erg\,cm\,s^{-1})}\sim1.6$). The detected emission lines (especially a strong and broad feature around 1\,keV) are of unknown origin and cannot be explained with emission from plasmas in photo- or collisional-ionization equilibrium. Such emission lines could be well described by a strongly blueshifted ($z\sim-0.3$) secondary reflection off the base of the equatorial outflows, which may reveal the link between the reprocessing of the inner accretion flow photons and the ejection. However, this scenario although being very promising is only tentative and will be tested with future observations., Comment: 15 pages, 17 figures, 1 table, accepted for publication in MNRAS

Accretion disks and coronae around massive black holes have been studied extensively, and they are known to be coupled. Over a period of 30 years, however, the X-ray (coronal) flux of Mrk 817 increased by a factor of 40 while its UV (disk) flux remained relatively steady. Recent high-cadence monitoring finds that the X-ray and UV continua in Mrk 817 are also decoupled on time scales of weeks and months. These findings could require mechanical beaming of the innermost accretion flow, and/or an absorber that shields the disk and/or broad line region (BLR) from the X-ray corona. Herein, we report on a 135 ks observation of Mrk 817 obtained with NuSTAR, complemented by simultaneous X-ray coverage via the Neil Gehrels Swift Observatory. The X-ray data strongly prefer a standard relativistic disk reflection model over plausible alternatives. Comparable fits with related models constrain the spin to lie in the range 0.5 < a < 1, and the viewing angle to lie between 10 deg. < theta < 22 deg. (including 1-sigma statistical errors and small systematic errors related to differences between the models). The spectra also reveal strong evidence of moderately ionized absorption, similar to but likely less extreme than obscuring events in NGC 5548 and NGC 3783. Archival Swift data suggest that the absorption may be variable. Particularly if the column density of this absorber is higher along the plane of the disk, it may intermittently mask or prevent coupling between the central engine, disk, and BLR in Mrk 817., Accepted for publication in ApJ Letters

LOFT (Large Observatory for X-ray Timing) is one of the five candidates that were considered by ESA as an M3 mission (with launch in 2022-2024) and has been studied during an extensive assessment phase. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. Its pointed instrument is the Large Area Detector (LAD), a 10 m2-class instrument operating in the 2-30keV range, which holds the capability to revolutionise studies of variability from X-ray sources on the millisecond time scales. The LAD instrument has now completed the assessment phase but was not down-selected for launch. However, during the assessment, most of the trade-offs have been closed leading to a robust and well documented design that will be reproposed in future ESA calls. In this talk, we will summarize the characteristics of the LAD design and give an overview of the expectations for the instrument capabilities. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

We report the results of a long campaign of time-series photome try on the nova-like variable UX Ursae Majoris during 2015. It spanned 150 nights, with ~ 1800 h ours of coverage on 121 separate nights. The star was in its normal ‘high state’ near m agnitude V = 13, with slow waves in the light curve and eclipses every 4.72 hours. Remarkably, t he star also showed a nearly sinusoidal signal with a full amplitude of 0.44 mag and a perio d of 3.680± 0.007 d. We interpret this as the signature of a retrograde precession (wobble) of th e accretion disc. The same period is manifest as a ±33 s wobble in the timings of mid-eclipse, indic ating that the disc’s centre of light moves with this period. The star also showed strong ‘negative s uperhumps’ at frequencies ft) or b + N and 2ft) or b + N, where w or b and N are respectively the orbital and precession frequencies. It is possible that these powerful signals have been present, unsu spected, throughout the more than 60 years of previous photometric studies., We thank the National Science Foundation for support of this re search (AST12-11129), and also the Mount Cuba Astronomical Foundation. Finally, we thank the American Association of Variable Star Obs ervers (AAVSO) for providing the infrast ructure and continued inspirat ion which makes programs like this possible.

In core-collapse supernovae, titanium-44 ((44)Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.87- and 78.32-kilo-electron volt emission lines from decay of (44)Ti produced in the supernova explosion. These lines are narrow and redshifted with a Doppler velocity of ~700 kilometers per second, direct evidence of large-scale asymmetry in the explosion.

We sampled phytoseiid mites (densities, diversity, and age structure) on several plants located in four uncultivated areas surrounding vineyards over 3 yr to determine how leaf structure affects populations. The plant composition of these areas greatly influenced the numbers and species of phytoseiids present. The relationships between leaf structure (trichome, pollen densities, number, and structure of domatia, leaf surface) and Kampimodromus aberrans (Oudemans) densities also were studied. The frequency of occurrence and the abundance of K. aberrans per cm2 were correlated to high trichome densities. A complex phylloplane (many hairs and shelters or domatia) could confer a competitive advantage to K. aberrans over other phytoseiid mite species. The number and the rating of domatia were important to K aberrans development; high proportions of immatures were observed only on plants with these structures. Pollen densities were significantly correlated to trichome densities; domatia structure had only a somewhat lesser effect. Our study shows that dense trichome and pollen levels are favorable to the development of K. aberrans populations and add perspective on the influence of domatia on this important predaceous mite.

We report on ASCA observations of the low mass X-ray binaries GX 354-0 and KS 1731-260. The spectrum of GX 354-0 is best described as a power-law or a Comptonized spectrum with tau ~ 5 and kT ~ 8 keV and a residual at ~6.5 keV. The residual may be a disk reflection or a Compton broadened Gaussian line from the hot inner ADAF-like coronal region. The absorption column density to the source is 2.9e22 cm^-2. No soft thermal component was detected. The spectrum from KS 1731-260 is softer and it is best fit with a two component model with a column density of 1.1e22 cm^-2. The likely interpretation is emission from a Comptonizing cloud with an optical depth tau>12 and either a neutron star or a disk blackbody emission. We discuss the likely location of the Comptonizing cloud for both sources within the context of several proposed emission models., Accepted for publication in the Astrophysical Journal

How structures of various scales formed and evolved from the early Universe up to present time is a fundamental question of astrophysics. EDGE will trace the cosmic history of the baryons from the early generations of massive stars by Gamma-Ray Burst (GRB) explosions, through the period of galaxy cluster formation, down to the very low redshift Universe, when between a third and one half of the baryons are expected to reside in cosmic filaments undergoing gravitational collapse by dark matter (the so-called warm hot intragalactic medium). In addition EDGE, with its unprecedented capabilities, will provide key results in many important fields. These scientific goals are feasible with a medium class mission using existing technology combined with innovative instrumental and observational capabilities by: (a) observing with fast reaction Gamma-Ray Bursts with a high spectral resolution (R ~ 500). This enables the study of their (star-forming) environment and the use of GRBs as back lights of large scale cosmological structures; (b) observing and surveying extended sources (galaxy clusters, WHIM) with high sensitivity using two wide field of view X-ray telescopes (one with a high angular resolution and the other with a high spectral resolution). The mission concept includes four main instruments: a Wide-field Spectrometer with excellent energy resolution (3 eV at 0.6 keV), a Wide- Field Imager with high angular resolution (HPD 15") constant over the full 1.4 degree field of view, and a Wide Field Monitor with a FOV of 1/4 of the sky, which will trigger the fast repointing to the GRB. Extension of its energy response up to 1 MeV will be achieved with a GRB detector with no imaging capability. This mission is proposed to ESA as part of the Cosmic Vision call. We will briefly review the science drivers and describe in more detail the payload of this mission.

Resume L'experience croissante des equipes de diagnostic antenatal permet de depister des anomalies de plus en plus discretes de l'appareil urinaire. Ainsi, un grand nombre de dilatations pyeliques est detecte sans que l'on puisse en affirmer le caractere pathologique. Patients et methodes. — Lors d'une etude retrospective de 78 patients, nous avons determine la valeur predictive positive (VPP) des signes echographiques antenatals d'uropathies malformatives. Resultats. — Cette VPP etait de 27.3 % lorsqu'il s'agissait d'une dilatation pyelique isolee. Elle etait de 100 % s'il s'y associait une dilatation des calices. Le diametre anteroposterieur du pyelon mesure lors du troisieme trimestre de la grossesse peut predire la gravite de l'atteinte renale apres la naissance, puisqu'il etait de 6.7 ± 2.15 mm pour le groupe des dilatations pyeliques postnatales non pathologiques, significativement inferieur aux 13.4 ± 3 mm du groupe des syndromes de jonction pyelo-ureterale de stade I et aux 17 ± 9 mm des autres unites renales pathologiques. L'echographie antenatale a en revanche une mauvaise sensibilite pour la detection du reflux vesico-ureteral, quatre reflux primitifs sur 14 ayant ete depistes en l'absence d'anomalie echographique antenatale homolaterale. Conclusion. — Nous proposons une strategic diagnostique qui tient compte de ces resultats de la morbidite et du cout des differents examens. Une exploration urologique est effectuee devant une dilatation des cavites renales superieure a 10 mm. Si l'echographie de controle apres la naissance montre une dilatation pyelique isolee inferieure a ce seuil, seule une surveillance clinique est prescrite, en signalant aux parents la possibilite d'un reflux vesico-ureteral et done la necessite d'un examen cytobacteriologique des urines devant toute fievre inexpliquee.

This essay describes the law of attempt as it stands today in the United States. It describes the requirements for liability in attempt—the mental state and required action. It gives an overview of specific intent as the required mental state. The essay then provides an outline of the different tests courts use to determine whether a defendant has attempted a crime or was simply preparing to do so. It also discusses the various limits of attempt law, including abandonment and impossibility. Keywords: abandonment; criminal law; criminology; attempt; law

We report on the development of a generic X‐ray instrument simulator to be used in simulations of future X‐ray missions. Based on a Monte Carlo approach the code generates photon events for sources in an X‐ray source catalogue such as the ROSAT all sky survey or the XMM‐Newton slew surveys and then models the imaging and detection process based on the available calibration files (e.g., point spread functions for the imaging). The output of the program are event lists, which can be analysed using standard software such as xselect. Due to its modular concept the simulation software can be easily adapted to different concepts of imaging detectors.As examples for the potential use of the simulation we present our studies for eROSITA and show results of simulations of the detector performance for the High Time Resolution Spectrometer and the Wide Field Imager on the International X‐ray Observatory.

The context is the SVOM satellite which is a French/Chinese gamma ray bursts observatory project. One of the instruments is named ECLAIRs, an X/Gamma ray telescope going from 4 keV to 250 keV. Its detection plane, the DPIX matrix, is composed by 200 XRDPIX developed for the ECLAIRS camera, a 6400 CdTe detectors array.

We present the SVOM (Space-based multi-band astronomical Variable Object Monitor) mission, that is being developed in cooperation between the Chinese National Space Agency (CNSA), the Chinese Academy of Science (CAS) and the French Space Agency (CNES). Its scientific objectives include the study of the GRB phenomenon, GRB physics and progenitors, cosmology, and fundamental physics. SVOM is designed to detect all known types of Gamma-Ray Bursts (GRBs), to provide fast and reliable GRB positions, to measure the broadband spectral characteristics and temporal properties of the GRB prompt emission. This will be obtained in first place thanks to a set of four space flown instruments. A wide field (~2 sr) coded mask telescope (ECLAIRs), operating in the 4-250 keV energy range, will provide the triggers and localizations, while a gamma-ray non-imaging spectrometer (GRM), sensitive in the 50 keV-5 MeV domain, will extend the prompt emission energy coverage. After a satellite slew, in order to place the GRB direction within field of view of the two narrow field instruments - a soft X-ray (XIAO), and a visible telescope (VT) - the GRB position will be refined and the study of the early phases of the GRB afterglow will be possible. A set of three ground based dedicated instruments, two robotic telescopes (GFTs) and a wide angle optical monitor (GWAC), will complement the space borne instruments. Thanks to the low energy trigger threshold (~4 keV) of the ECLAIRs, SVOM is ideally suited for the detection of soft, hence potentially most distant, GRBs. Its observing strategy is optimized to facilitate follow-up observations from the largest ground based facilities., Comment: Proceedings of the 6th Huntsville Symposium on Gamma-Ray Bursts (October 20-23 2008). Figures in colour with respect to the published version

SVOM is a Chinese‐French mission, to be launched in late 2013 on a Low Earth Orbit (h = 630 km, i = 30°). ECLAIRs will provide the Gamma‐Ray Burst (GRB) triggers to the narrow field instruments on board SVOM and on the ground. ECLAIRs will detect GRBs between 4 keV and 250 keV. This makes ECLAIRs particularly sensitive to high redshift GRBs and nearby low luminosity events. This paper presents the main characteristics of ECLAIRs, its architecture, as well as its estimated performance.

The general problem of calibrating soft gamma-ray (100 keV–1 MeV) detectors is illustrated in the case of the SIGMA experiment. Particularly, the adv

Cat-scratch disease is a well-known cause of regional adenopathy in immunocompetent children. Rarely, patients may present with symptoms simulating a neoplastic disease. The case of a 12-year-old boy with fever, swelling of the chest wall and hepatosplenic nodules is reported. Histological analysis of biopsy specimen obtained from the chest wall lesion and the liver revealed granulomatous reaction without malignant cells. Serological investigations were positive for Bartonella species. The symptoms and the lesions disappeared after oral antibiotic therapy (ciprofloxacin) was started. The patient remained symptom-free 12 months later. Conclusion The present case emphasizes the wide spectrum of clinical manifestations associated with cat-scratch disease which should be investigated as differential diagnosis of manifestations suggesting a neoplastic disease in children.

The X and Gamma-ray telescope ECLAIRs is foreseen to be launched on a low Earth orbit (h=630 km, i=30 degrees) aboard the SVOM satellite (Space-based multi-band astronomical Variable Objects Monitor), a French-Chinese mission with Italian contribution. Observations are expected to start in 2013. It has been designed to detect and localize Gamma-Ray Bursts (GRBs) or persistent sources of the sky, thanks to its wide field of view (about 2 sr) and its remarkable sensitivity in the 4-250 keV energy range, with enhanced imaging sensitivity in the 4-70 keV energy band. These characteristics are well suited to detect highly redshifted GRBs, and consequently to provide fast and accurate triggers to other onboard or ground-based instruments able to follow-up the detected events in a very short time from the optical wavelength bands up to the few MeV Gamma-Ray domain., Proccedings of the "2008 Nanjing GRB Conference", June 23-27 2008, Nanjing, China

We report on the detailed modelling of the X-ray spectra of three likely neutron stars. The neutron stars, observed with XMM-Newton are found in three quiescent X-ray binaries in the globular clusters: omega Cen, M 13 and NGC 2808. Whether they are accreting at very low rates or radiating energy from an accretion heated core, their X-ray spectra are expected to be those of a hydrogen atmosphere. We use and compare publicly available hydrogen atmosphere models, with constant and varying surface gravities to constrain the masses and radii of the neutron stars. Thanks to the high XMM-Newton throughput, and the accurate distances available for these clusters, using the latest science analysis software release and calibration of the XMM-Newton EPIC cameras, we derive the most stringent constraints on the masses and radii of the neutron stars obtained to date from these systems. A comparison of the models indicate that previously used hydrogen atmosphere models (assuming constant surface gravity) tend to underestimate the mass and overestimate the radius of neutron stars. Our data constrain the allowed equations of state to those which concern normal nucleonic matter and one possible strange quark matter model, thus constraining radii to be from 8 km and masses up to 2.4 M$_\odot$., 10 pages, 8 figures, accepted to be published in The Astrophysical Journal

This paper describes the performance of XMM-Newton for serendipitous surveys and summarises the scope and potential of the XMM-Newton Serendipitous Survey. The role of the Survey Science Centre (SSC) in the XMM-Newton project is outlined. The SSC's follow-up and identification programme for the XMM-Newton serendipitous survey is described together with the presentation of some of the first results., 9 pages, 4 figs, accepted for A&A Letters, XMM issue, version with higher resolution figs available from http://xmmssc-www.star.le.ac.uk/papers

Cases of meningitis due to Bacteroides fragilis are rare; we report a case revealing a meningorectal fistula.A 2-month-old infant developed a severe sepsis syndrome following a rectosigmoidoscopy for rectal bleeding. Lumbar puncture diagnosed bacterial meningitis. Cerebrospinal fluid (CSF) culture evidenced B fragilis with betalactamase. The initial antibiotherapy was changed for imipenem-metronidazole, which is at present the recommended antibiotherapy. Malformation including pre-spinal tumor and meningorectal fistula was evoked on magnetic resonance imaging (MRI) and confirmed by surgery. The outcome was favorable after surgery and antibiotherapy.B fragilis meningitis are usually associated with sepsis, whose origin is obvious. In our case, meningitis was isolated, revealing a meningorectal fistula.

Three type I X-ray bursts and one burst candidate from 4U 1608-52 were observed with RXTE on March 22, 1996. Between the two strongest bursts, an enhanced noise component below 0.01 Hz was observed in the X-ray light curve with RXTE/PCA. It is probably caused by the subsequent time-dependent nuclear burning after the main X-ray burst. This supports the idea that there is a correlation between the Very-Low-Frequency-Noise (VLFN) in Low-Mass X-ray Binaries (LMXBs) and the nuclear burning. Assuming that the time scale of the variations is the time scale for one fire to ignite another, our result suggests the burning front was propagating at less than 3.0×104 cm s−1 on the neutron star surface.

The increasing experience with prenatal ultrasonographic diagnosis allows detection of more and more mild urinary tract anomalies. Thus, the clinical significance of many pyelectasis detected before birth is not known.From a retrospective study of 78 patients, we determined the positive predictive value (PPV) of prenatal ultrasound findings for urinary tract malformations.This PPV was 27.3% when the prenatal pelvic dilatation was isolated, but grew up to 100% if a caliceal dilatation was associated. Renal pelvic diameter in the third trimester of pregnancy could predict the degree of post-natal renal impairment, as pelvic size was 6.7 +/- 2.15 mm for the post-natal pyelectasis group, significatively smaller than 13.4 +/- 3 mm in the ureteropelvic junction obstruction group (grade 1) and than 17 +/- 9 mm in other pathological renal units. On the other hand, antenatal ultrasound had a bad sensibility for vesico-ureteral reflux detection, four primary reflux among 14 being detected without homolateral antenatal ultrasound anomaly.According these results, we propose a post-natal diagnostic strategy. Urological explorations are performed when the prenatal renal pelvic diameter is larger than 10 mm. If the postnatal ultrasound shows an isolated pyelectasis below this level, a clinical follow-up is advised, the parents being informed of the possibility of vesico-ureteral reflux and of the necessity to perform a cytobacteriological exam of urines in case of unexplained fever.

Strong oscillations near 1000 Hz have been discovered in a number of low mass x-ray binaries with NASA’s Rossi X-Ray Timing Explorer. Their behavior should ultimately lead us to a better understanding of the accretion dynamics and the fundamental properties of the neutron star itself. Here we summarize the known properties of fast QPOs, focusing on results from the source 4U 0614+091. We highlight some of the aspects yet to be explored.

The X-ray burster 1E1724-3045, located in the globular cluster Terzan 2 was observed on November 1996 for 100 ksec with the PCA and HEXTE experiments aboard the Rossi X-ray Timing Explorer. During the observation, the PCA count rate was about 470 cts/s in the 2–20 keV range (background substracted). We have characterized the aperiodic variability of the source over a wide frequency band (2 10−3−40 Hz). The 2–20 keV emission of this source shows a light level of noise variability (RMS ∼25%). The Fourier spectrum can be modelled in terms of the shot noise model with two characteristic lifetimes of 670 and 16 msec although a continuous distribution of shots lifetimes can not be excluded. These two components account for about the same contribution to the total RMS of the source (∼10%). In addition to these components, a broad and asymetric peaked noise feature, located at 0.8 Hz, appears in the spectrum. This QPO-like feature accounts for a ∼5% of the RMS. Both the lifetimes of the shots and the QPO frequenc...

The CFA BATSE IMAGE SEARCH (CBIS) system allows automated analysis of large sets of BATSE images. CBIS is being used to conduct a deep survey of the Galactic plane to search for faint transients (∼100 mCrab) in the archival data [2]. Furthermore, together with the earth occultation technique [3], CBIS is now applied to a real time imaging survey of the plane to discover new transients and monitor known sources. The CBIS processing is made of two sequential steps: First, the images are scanned to search for excesses. Second, the positions of all these excesses are cross-correlated to produce a list of candidate sources. In this paper, we will detail the algorithms of the scanner and the cross-correlator.

Adamantinoma of the long bones in a very rare tumor that mainly affects the tibia. Its diagnosis is difficult both radiologically, as the lesion appears as a poorly specific metaphyseal lacuna with or without periosteal reaction, and histologically. Its prognosis used to be guarded because of recurrence and of possible metastatic diffusion, but it has been considerably improved by wide resection with reconstruction. On the occasion of a new case, the authors describe the appearance observed with MRI and the merits of this examination for the preoperative assessment.

As nasal endoscopy, high resolution CT is a part of the chronic rhinosinusitis pre-operative assessment. It shows, thanks to a precise and anatomical study of the ethmoid and sinusal draining, the extension of the diseases and the local morphological variations which predispose to chronic diseases. The main aspects of chronic sinusitis, nasal polyposis and fungal maxillary sinus diseases are reported. The frequency of individual morphological variations and the mucosal changes due to a nasal cycle require a great care in the interpretation of the diseases.

A case of chondrosarcoma arising from the 7th left rib in a patient with multiple exostosis disease is reported. The initial CT scan feature is a purely intrathoracic mass with a parietal and pericardial junction and calcifications within the tumor. A review of the literature about the costal chondrosarcoma and their CT scan features is done and shows the uncommon initial aspect of this case.

Two cases of torsion of the gallbladder in children (ages 5 and 7) are reported, and the relevant literature is reviewed. The condition is extremely rare in the pediatric population, and the correct diagnosis is rarely made preoperatively. However, the clinical presentation may be evocative of the diagnosis. Ultrasonography is helpful for the diagnosis, but ultrasonographic modifications of the gallbladder occur after the onset of the pain. The treatment of this condition is early cholecystectomy.

The primitive thoracic seminoma is a rare tumor. Given their low frequency, these tumour have rarely been the object of C.T. exploration. It determines the compressive effect on neighbouring organs, the volume and extensive character of the tumor. C.T. exploration allows proper surveillance after therapeutic.

The sudden development of an abdominal mass following umbilical artery catheterization during neonatal reanimation in a 1-month-old infant of an alcoholic mother was found to be due to an aneurysm of the abdominal aorta. Diagnosis was established by computed tomography and confirmed by arteriography. In the absence of any pathological examination, surgical treatment having been temporarily delayed, a mycotic origin for the aneurysm was suggested by the conditions of onset. A review of the 13 cases of primary mycotic aneurysms of the abdominal aorta in infants reported in the literature emphasizes the rare but serious nature of these lesions at this age.

A case of aneurysm of the arch of the greater azygos vein is reported. This extremely rare congenital anomaly appears as a large rounded opacity in the anterosuperior mediastinum. Though diagnosis may be suspected by the variations in size according to the period of observation and the position of the patient, if can only be confirmed by angiography, to eliminate an aneurysm of the superior vena cava or one of azygos vein from obstruction of the inferior vena cava.