Association between Anatomical Variations and maxillary canine impaction: A retrospective study in orthodontics

This study aims to evaluate whether or not there is a higher prevalence of skeletal abnormalities in subjects with maxillary canine impaction (MCI). This retrospective study was performed on 67 subjects with maxillary canine impaction (test group) and on 67 patients without dental displacement (control group). Sella turcica bridging (SB), ponticulus posticus (PP), atlas posterior arch deficiency (APAD) and the morphology of sella turcica and pterygopalatine fissure were evaluated on lateral cephalometric radiographs. Statistical analysis was performed using chi-square, Mann-Whitney test and multivariate logistic models; the level of significance was p < 0.05. Results showed that in the test and control groups 87% and 62.7% of patients had SB, respectively. PP was observed in 60% of patients in the test group and in 16.4% of patients in the control group. APAD was observed in 9% of test group and in 4.5% of the control group. Skeletal anomalies were significantly increased (p < 0.05) in subjects with MCI. A significant difference between the groups was observed in regards to the shape of the pterygopalatine fissure, found to be less wide and longer in the test group. SB, PP and APAD were higher in subjects with MCI; furthermore, an elongated pterygopalatine fissure was significantly associated with MCI

The near-infrared and ice-band variability of Haro 6-10

We have monitored the angularly resolved near infrared and 3.1 micron ice-band flux of the components of the young binary Haro 6-10 on 23 occasions during the years 1988 to 2000. Our observations reveal that both the visible star Haro 6-10 (Haro 6-10S) and its infrared companion (Haro 6-10N) show significant variation in flux on time scales as short as a month. The substantial flux decrease of Haro 6-10S over the last four years carries the reddening signature of increased extinction. However, a comparable K-band flux increase observed in the IRC is associated with a dimming in the H-band and cannot be explained by lower extinction. Absorption in the 3.1 micron water-ice feature was always greater towards the IRC during our observations, indicating a larger amount of obscuring material along its line of sight. We detect variability in the ice-band absorption towards Haro 6-10S and Haro 6-10N, significant at the 3.5 sigma and 2.0 sigma levels, respectively.Comment: 8 pages, 6 Figures, Accepted for Publication in Astronomy & Astrophysic

Fringe Tracker for the VLTI Spectro-Imager

The implementation of the simultaneous combination of several telescopes (from four to eight) available at Very Large Telescope Interferometer (VLTI) will allow the new generation interferometric instrumentation to achieve interferometric image synthesis with unprecedented resolution and efficiency. The VLTI Spectro Imager (VSI) is the proposed second-generation near-infrared multi-beam instrument for the Very Large Telescope Interferometer, featuring three band operations (J, H and K), high angular resolutions (down to 1.1 milliarcsecond) and high spectral resolutions. VSI will be equipped with its own internal Fringe Tracker (FT), which will measure and compensate the atmospheric perturbations to the relative beam phase, and in turn will provide stable and prolonged observing conditions down to the magnitude K=13 for the scientific combiner. In its baseline configuration, VSI FT is designed to implement, from the very start, the minimum redundancy combination in a nearest neighbor scheme of six telescopes over six baselines, thus offering better options for rejection of large intensity or phase fluctuations over each beam, due to the symmetric set-up. The planar geometry solution of the FT beam combiner is devised to be easily scalable either to four or eight telescopes, in accordance to the three phase development considered for VSI. The proposed design, based on minimum redundancy combination and bulk optics solution, is described in terms of opto-mechanical concept, performance and key operational aspects.Comment: 11 pages, to be published in Proc. SPIE conference 7013 "Optical and Infrared Interferometry", Schoeller, Danchi, and Delplancke, F. (eds.

Naturalization of current social representations of children and adolescents

Convergen en esta investigación el interés de docentes de la facultad en proporcionar, instrumentos a partir del conocimiento científico, a los espacios de intervención sobre violencia en la infancia y adolescencia. Ello se conjuga con la preocupación de profesionales que se desempeñan laboralmente en relación a esta problemática, quienes observan la inexistencia de transformaciones paradigmáticas y conceptuales en los escenarios donde se producen las situaciones planteadas. Por lo anteriormente descrito se hace imperioso, analizar científicamente el tema, para proporcionar nuevos conocimientos; a fin de dar posibles respuestas A la sociedad e instituciones

VSI: the VLTI spectro-imager

The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions down to 1.1 milliarcsecond and spectral resolutions up to R=12000. Targets as faint as K=13 will be imaged without requiring a brighter nearby reference object. The unique combination of high-dynamic-range imaging at high angular resolution and high spectral resolution enables a scientific program which serves a broad user community and at the same time provides the opportunity for breakthroughs in many areas of astrophysic including: probing the initial conditions for planet formation in the AU-scale environments of young stars; imaging convective cells and other phenomena on the surfaces of stars; mapping the chemical and physical environments of evolved stars, stellar remnants, and stellar winds; and disentangling the central regions of active galactic nuclei and supermassive black holes. VSI will provide these new capabilities using technologies which have been extensively tested in the past and VSI requires little in terms of new infrastructure on the VLTI. At the same time, VSI will be able to make maximum use of new infrastructure as it becomes available; for example, by combining 4, 6 and eventually 8 telescopes, enabling rapid imaging through the measurement of up to 28 visibilities in every wavelength channel within a few minutes. The current studies are focused on a 4-telescope version with an upgrade to a 6-telescope one. The instrument contains its own fringe tracker and tip-tilt control in order to reduce the constraints on the VLTI infrastructure and maximize the scientific return.Comment: 12 pages, to be published in Proc. SPIE conference 7013 "Optical and Infrared Interferometry", Schoeller, Danchi, and Delplancke, F. (eds.). See also http://vsi.obs.ujf-grenoble.f

Milli-arcsecond astrophysics with VSI, the VLTI spectro-imager in the ELT era

Nowadays, compact sources like surfaces of nearby stars, circumstellar environments of stars from early stages to the most evolved ones and surroundings of active galactic nuclei can be investigated at milli-arcsecond scales only with the VLT in its interferometric mode. We propose a spectro-imager, named VSI (VLTI spectro-imager), which is capable to probe these sources both over spatial and spectral scales in the near-infrared domain. This instrument will provide information complementary to what is obtained at the same time with ALMA at different wavelengths and the extreme large telescopes.Comment: 8 pages. To be published in the proceedings of the ESO workshop "Science with the VLT in the ELT Era", held in Garching (Germany) on 8-12 October 2007, A. Moorwood edito

Euclid Collaboration IV: Impact of Undetected Galaxies on Weak-Lensing Shear Measurements

In modern weak-lensing surveys, the common approach to correct for residual systematic biases in the shear is to calibrate shape measurement algorithms using simulations. These simulations must fully capture the complexity of the observations to avoid introducing any additional bias. In this paper we study the importance of faint galaxies below the observational detection limit of a survey. We simulate simplified Euclid VIS images including and excluding this faint population, and measure the shift in the multiplicative shear bias between the two sets of simulations. We measure the shear with three different algorithms: a moment-based approach, model fitting, and machine learning. We find that for all methods, a spatially uniform random distribution of faint galaxies introduces a shear multiplicative bias of the order of a few times $10^{-3}$. This value increases to the order of $10^{-2}$ when including the clustering of the faint galaxies, as measured in the Hubble Space Telescope Ultra-Deep Field. The magnification of the faint background galaxies due to the brighter galaxies along the line of sight is found to have a negligible impact on the multiplicative bias. We conclude that the undetected galaxies must be included in the calibration simulations with proper clustering properties down to magnitude 28 in order to reach a residual uncertainty on the multiplicative shear bias calibration of a few times $10^{-4}$, in line with the $2\times10^{-3}$ total accuracy budget required by the scientific objectives of the Euclid survey. We propose two complementary methods for including faint galaxy clustering in the calibration simulations.Comment: Version published in A&

Long term health related quality of life following colorectal cancer surgery: patient reported outcomes in a remote follow-up population

Background: Remote follow-up (RFU) after colorectal cancer (CRC) surgery allows delivery of surveillance tests without the need for regular outpatient clinical appointments. However, little is known about health related quality of life (HRQoL) in RFU patients.Methods: EQ-5D, QLQ-C30 and QLQ-C29 questionnaires were distributed to CRC patients enrolled in a RFU programme. The primary outcome of HRQoL scores was analysed by year of RFU, demographics, operation-type, stoma and adherence to RFU protocols. Results:428 respondents (59.3%), mean age of 71years(SD 10.1) and a median RFU time of 2.6years (IQR: 1.6-4.8 years) were included. 26.6% of patients reported ‘perfect health’. The median EQ-5D index score was 0.785 (IQR: 0.671-1) and QLQ-C30 Global HRQoL score was 75 (IQR: 58.3-83.3). Females had significantly lower EQ-5D median score of 0.767 (IQR: 0.666-0.879, p=0.0088). Lower QLQ-C30 HRQoL scores were seen in stoma patients, median 66.6 (IQR: 58.3-83.3, p=0.0029). Erectile dysfunction (p=0.0006) and poor body image (p=0.001) were also reported more frequently in stoma patients. Patients undergoing right-sided resection reported a lower median EQ-5D score of 0.765 (IQR: 0.666-0.879, p=0.028) and higher pain severity (p=0.0367) compared with left-sided resections. There were 128 (29.4%) patients that breached RFU protocol and were seen in adhoc colorectal clinics. However, there was no statistical difference in HRQoL between patients who adhered to or breached RFU protocols.Conclusions: Overall HRQoL in patients in RFU is good, with no difference in those strictly followed up remotely. However, females, right-sided resections and patients with stomas may require additional clinical reviews.

System overview of the VLTI Spectro-Imager

The VLTI Spectro Imager project aims to perform imaging with a temporal resolution of 1 night and with a maximum angular resolution of 1 milliarcsecond, making best use of the Very Large Telescope Interferometer capabilities. To fulfill the scientific goals (see Garcia et. al.), the system requirements are: a) combining 4 to 6 beams; b) working in spectral bands J, H and K; c) spectral resolution from R= 100 to 12000; and d) internal fringe tracking on-axis, or off-axis when associated to the PRIMA dual-beam facility. The concept of VSI consists on 6 sub-systems: a common path distributing the light between the fringe tracker and the scientific instrument, the fringe tracker ensuring the co-phasing of the array, the scientific instrument delivering the interferometric observables and a calibration tool providing sources for internal alignment and interferometric calibrations. The two remaining sub-systems are the control system and the observation support software dedicated to the reduction of the interferometric data. This paper presents the global concept of VSI science path including the common path, the scientific instrument and the calibration tool. The scientific combination using a set of integrated optics multi-way beam combiners to provide high-stability visibility and closure phase measurements are also described. Finally we will address the performance budget of the global VSI instrument. The fringe tracker and scientific spectrograph will be shortly described

Euclid: On the reduced shear approximation and magnification bias for Stage IV cosmic shear experiments

Stage IV weak lensing experiments will offer more than an order of magnitude leap in precision. We must therefore ensure that our analyses remain accurate in this new era. Accordingly, previously ignored systematic effects must be addressed. In this work, we evaluate the impact of the reduced shear approximation and magnification bias, on the information obtained from the angular power spectrum. To first-order, the statistics of reduced shear, a combination of shear and convergence, are taken to be equal to those of shear. However, this approximation can induce a bias in the cosmological parameters that can no longer be neglected. A separate bias arises from the statistics of shear being altered by the preferential selection of galaxies and the dilution of their surface densities, in high-magnification regions. The corrections for these systematic effects take similar forms, allowing them to be treated together. We calculate the impact of neglecting these effects on the cosmological parameters that would be determined from Euclid, using cosmic shear tomography. We also demonstrate how the reduced shear correction can be calculated using a lognormal field forward modelling approach. These effects cause significant biases in Omega_m, n_s, sigma_8, Omega_DE, w_0, and w_a of -0.51 sigma, -0.36 sigma, 0.37 sigma, 1.36 sigma, -0.66 sigma, and 1.21 sigma, respectively. We then show that these lensing biases interact with another systematic: the intrinsic alignment of galaxies. Accordingly, we develop the formalism for an intrinsic alignment-enhanced lensing bias correction. Applying this to Euclid, we find that the additional terms introduced by this correction are sub-dominant