602 research outputs found

    The indirect effect of contextual factors on the emotional distress of infertile couples

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    Few studies were dedicated to study the role of contextual factors, such as the socioeconomic status and urban rural residence in emotional distress of infertile couples. This study aimed to explore the impact of contextual factors on emotional distress, either directly or by affecting the importance of parenthood in one’s life which in turn affects emotional distress. In this cross-sectional study, 70 couples recruited during hormonal stimulation phase prior to IVF completed clinical and sociodemographic forms and self-report questionnaires assessing representations about the importance of parenthood and emotional distress. Path analysis using structural equation modelling was used to examine direct and indirect effects among variables. Results indicated that social economic status and Urban-Rural residence had an impact in emotional distress by affecting the representations about the importance of parenthood in one’s life. Gender differences were found regarding model paths, suggesting that the social context may contribute more to women’s emotional distress than to their partners’ distress. When delineating psychological interventions, health care providers should consider that cultural values about children and parenthood contribute to shape the infertility experienc

    Lamb Production Costs: Analyses of Composition and Elasticities Analysis of Lamb Production Costs

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    Since lamb is a commodity, producers cannot control the price of the product they sell. Therefore, managing production costs is a necessity. We explored the study of elasticities as a tool for basing decision-making in sheep production, and aimed at investigating the composition and elasticities of lamb production costs, and their influence on the performance of the activity. A representative sheep production farm, designed in a panel meeting, was the base for calculation of lamb production cost. We then performed studies of: i) costs composition, and ii) cost elasticities for prices of inputs and for zootechnical indicators. Variable costs represented 64.15% of total cost, while 21.66% were represented by operational fixed costs, and 14.19% by the income of the factors. As for elasticities to input prices, the opportunity cost of land was the item to which production cost was more sensitive: a 1% increase in its price would cause a 0.2666% increase in lamb cost. Meanwhile, the impact of increasing any technical indicator was significantly higher than the impact of rising input prices. A 1% increase in weight at slaughter, for example, would reduce total cost in 0.91%. The greatest obstacle to economic viability of sheep production under the observed conditions is low technical efficiency. Increased production costs are more related to deficient zootechnical indexes than to high expenses

    Evaluation of Antipsychotic Drugs’ Stability in Oral Fluid Samples

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    Antipsychotics have narrow therapeutic windows, and their monitoring in biological fluids is therefore important; consequently, stability in those fluids must be investigated during method development and validation. This work evaluates the stability of chlorpromazine, levomepromazine, cyamemazine, clozapine, haloperidol, and quetiapine in oral fluid (OF) samples, using the dried saliva spots (DSS) sampling approach and gas chromatography coupled to tandem mass spectrometry. Since many parameters can influence the stability of the target analytes, design of experiments was adopted to check the crucial factors that affect that stability in a multivariate fashion. The studied parameters were the presence of preservatives at different concentrations, temperature, light, and time. It was possible to observe that antipsychotic stability improved when OF samples in DSS were stored at 4 °C, with a low ascorbic acid concentration, and in the absence of light. With these conditions, chlorpromazine and quetiapine were stable for 14 days, clozapine and haloperidol were stable for 28 days, levomepromazine remained stable for 44 days, and cyamemazine was stable for the entire monitored period (146 days). This is the first study that evaluates the stability of these antipsychotics in OF samples after application to DSS cards.info:eu-repo/semantics/publishedVersio

    A search for pulsations in the HgMn star HD 45975 with CoRoT photometry and ground-based spectroscopy

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    The existence of pulsations in HgMn stars is still being debated. To provide the first unambiguous observational detection of pulsations in this class of chemically peculiar objects, the bright star HD 45975 was monitored for nearly two months by the CoRoT satellite. Independent analyses of the light curve provides evidence of monoperiodic variations with a frequency of 0.7572 c/d and a peak-to-peak amplitude of ~2800 ppm. Multisite, ground-based spectroscopic observations overlapping the CoRoT observations show the star to be a long-period, single-lined binary. Furthermore, with the notable exception of mercury, they reveal the same periodicity as in photometry in the line moments of chemical species exhibiting strong overabundances (e.g., Mn and Y). In contrast, lines of other elements do not show significant variations. As found in other HgMn stars, the pattern of variability consists in an absorption bump moving redwards across the line profiles. We argue that the photometric and spectroscopic changes are more consistent with an interpretation in terms of rotational modulation of spots at the stellar surface. In this framework, the existence of pulsations producing photometric variations above the ~50 ppm level is unlikely in HD 45975. This provides strong constraints on the excitation/damping of pulsation modes in this HgMn star.Comment: Accepted for publication in A&A, 14 pages, 15 colour figures (revised version after language editing

    AzTEC 1.1 mm Observations of the MBM12 Molecular Cloud

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    We present 1.1 mm observations of the dust continuum emission from the MBM12 high-latitude molecular cloud observed with the Astronomical Thermal Emission Camera (AzTEC) mounted on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. We surveyed a 6.34 deg2^2 centered on MBM12, making this the largest area that has ever been surveyed in this region with submillimeter and millimeter telescopes. Eight secure individual sources were detected with a signal-to-noise ratio of over 4.4. These eight AzTEC sources can be considered to be real astronomical objects compared to the other candidates based on calculations of the false detection rate. The distribution of the detected 1.1 mm sources or compact 1.1 mm peaks is spatially anti-correlated with that of the 100 micronm emission and the 12^{12}CO emission. We detected the 1.1 mm dust continuum emitting sources associated with two classical T Tauri stars, LkHalpha262 and LkHalpha264. Observations of spectral energy distributions (SEDs) indicate that LkHalpha262 is likely to be Class II (pre-main-sequence star), but there are also indications that it could be a late Class I (protostar). A flared disk and a bipolar cavity in the models of Class I sources lead to more complicated SEDs. From the present AzTEC observations of the MBM12 region, it appears that other sources detected with AzTEC are likely to be extragalactic and located behind MBM12. Some of these have radio counterparts and their star formation rates are derived from a fit of the SEDs to the photometric evolution of galaxies in which the effects of a dusty interstellar medium have been included.Comment: 8 pages, 6 figures, The Astrophysical Journal, in pres

    Signatures of internal rotation discovered in the Kepler data of five slowly pulsating B stars

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    Context. Massive stars are important building blocks of the Universe, and their stellar structure and evolution models are fundamental cornerstones of various fields in modern astrophysics. The precision of these models is strongly limited by our lack of understanding of various internal mixing processes that significantly influence the lifetime of these objects, such as core overshoot, chemical mixing, or the internal differential rotation. Aims. Our goal is to calibrate models by extending the sample of available seismic studies of slowly pulsating B (SPB) stars, providing input for theoretical modelling efforts that will deliver precise constraints on the parameters describing the internal mixing processes in these objects. Methods. We used spectral synthesis and disentangling techniques to derive fundamental parameters and to determine precise orbital parameters from high-resolution spectra. We employed custom masks to construct light curves from the virtually uninterrupted four year long Kepler pixel data and used standard time-series analysis tools to construct a set of significant frequencies for each target. These sets were first filtered from combination frequencies, and then screened for period spacing patterns. Results. We detect gravity mode period series of modes, of the same degree ℓ with consecutive radial order n, in four new and one revisited SPB star. These series (covering typically 10 to 40 radial orders) are clearly influenced by moderate to fast rotation and carry signatures of chemical mixing processes. Furthermore, they are predominantly prograde dipole series. Our spectroscopic analysis, in addition to placing each object inside the SPB instability strip and identifying KIC 4930889 as an SB2 binary, reveals that KIC 11971405 is a fast rotator that shows very weak Be signatures. Together with the observed photometric outbursts this illustrates that this Be star is a fast rotating SPB star. We hypothesise that the outbursts might be connected to its very densely compressed oscillation spectrum

    The Gaia-ESO Survey: Chromospheric Emission, Accretion Properties, and Rotation in γ\gamma Velorum and Chamaeleon I

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    We use the fundamental parameters delivered by the GES consortium in the first internal data release to select the members of γ\gamma Vel and Cha I among the UVES and GIRAFFE spectroscopic observations. A total of 140 γ\gamma Vel members and 74 Cha I members were studied. We calculated stellar luminosities through spectral energy distributions, while stellar masses were derived by comparison with evolutionary tracks. The spectral subtraction of low-activity and slowly rotating templates, which are rotationally broadened to match the vsiniv\sin i of the targets, enabled us to measure the equivalent widths (EWs) and the fluxes in the Hα\alpha and Hβ\beta lines. The Hα\alpha line was also used for identifying accreting objects and for evaluating the mass accretion rate (M˙acc\dot M_{\rm acc}). The distribution of vsiniv\sin i for the members of γ\gamma Vel displays a peak at about 10 km s1^{-1} with a tail toward faster rotators. There is also some indication of a different vsiniv\sin i distribution for the members of its two kinematical populations. Only a handful of stars in γ\gamma Vel display signatures of accretion, while many more accretors were detected in the younger Cha~I. Accreting and active stars occupy two different regions in a TeffT_{\rm eff}-flux diagram and we propose a criterion for distinguishing them. We derive M˙acc\dot M_{\rm acc} in the ranges 101110^{-11}-109M10^{-9} M_\odotyr1^{-1} and 101010^{-10}-107M10^{-7} M_\odotyr1^{-1} for γ\gamma Vel and Cha I accretors, respectively. We find less scatter in the M˙accM\dot M_{\rm acc}-M_\star relation derived through the Hα\alpha EWs, when compared to the Hα\alpha 10%W10\%W diagnostics, in agreement with other authors

    Three-Dimensional Speckle-Tracking Echocardiography for the Global and Regional Assessments of Left Ventricle Myocardial Deformation in Breast Cancer Patients Treated with Anthracyclines

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    Background: Assessment of 2D/3D left ventricular ejection fraction (LVEF) and 2D global longitudinal strain (GLS) is the gold standard for diagnosing cancer therapeutics-related cardiac dysfunction (CTRCD). Although 3D speckle-tracking echocardiography (STE) has several advantages, it is not used in this setting. Methods: 105 breast cancer patients who underwent serial echocardiographic assessment during anthracycline therapy were included. STE was used to estimate 2D GLS, 3D GLS, 3D global circumferential strain (GCS), 3D global radial strain (GRS), and 3D global area strain (GAS). CTRCD was defined as an absolute decrease in 2D/3D LVEF > 10% to a value 15%. Results: 24 patients developed CTRCD. There was a significant worsening of all 3D strain parameters during chemotherapy. 3D strain regional analysis showed impaired contractility in the anterior, inferior, and septal walls. Variations of 3D GRS and 3D GCS were associated with a higher incidence of CTRCD and the variation of 3D GRS was an independent predictor of CTRCD. Variations of 3D GCS and 3D GRS had a good discrimination for predicting CTRCD, with optimal cutoff values of - 34.2% for 3D GCS and - 34.4% for 3D GRS. These variations were observed 45 and 23 days before the diagnosis of CTRCD, respectively. Conclusion: Variations of 3D strain parameters were predictive of and preceded CTRCD, and thus have added value over currently recommended 2D/3D LVEF and 2D GLS. Routine application of this technique should be considered to offer targeted monitoring and timely initiation of cardioprotective treatment.info:eu-repo/semantics/publishedVersio

    CSI 2264: Accretion process in classical T Tauri stars in the young cluster NGC 2264

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    Context. NGC 2264 is a young stellar cluster (~3 Myr) with hundreds of low-mass accreting stars that allow a detailed analysis of the accretion process taking place in the pre-main sequence. Aims. Our goal is to relate the photometric and spectroscopic variability of classical T Tauri stars to the physical processes acting in the stellar and circumstellar environment, within a few stellar radii from the star. Methods. NGC 2264 was the target of a multiwavelength observational campaign with CoRoT, MOST, Spitzer, and Chandra satellites and photometric and spectroscopic observations from the ground. We classified the CoRoT light curves of accreting systems according to their morphology and compared our classification to several accretion diagnostics and disk parameters. Results. The morphology of the CoRoT light curve reflects the evolution of the accretion process and of the inner disk region. Accretion burst stars present high mass-accretion rates and optically thick inner disks. AA Tau-like systems, whose light curves are dominated by circumstellar dust obscuration, show intermediate mass-accretion rates and are located in the transition of thick to anemic disks. Classical T Tauri stars with spot-like light curves correspond mostly to systems with a low mass-accretion rate and low mid-IR excess. About 30% of the classical T Tauri stars observed in the 2008 and 2011 CoRoT runs changed their light-curve morphology. Transitions from AA Tau-like and spot-like to aperiodic light curves and vice versa were common. The analysis of the Hα emission line variability of 58 accreting stars showed that 8 presented a periodicity that in a few cases was coincident with the photometric period. The blue and red wings of the Hα line profiles often do not correlate with each other, indicating that they are strongly influenced by different physical processes. Classical T Tauri stars have a dynamic stellar and circumstellar environment that can be explained by magnetospheric accretion and outflow models, including variations from stable to unstable accretion regimes on timescales of a few years

    An Infrared Coronagraphic Survey for Substellar Companions

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    We have used the F160W filter (1.4-1.8 um) and the coronagraph on the Near-InfraRed Camera and Multi-Object Spectrometer (NICMOS) on the Hubble Space Telescope (HST) to survey 45 single stars with a median age of 0.15 Gyr, an average distance of 30 pc, and an average H-magnitude of 7 mag. For the median age we were capable of detecting a 30 M_Jup companion at separations between 15 and 200 AU. A 5 M_Jup object could have been detected at 30 AU around 36% of our primaries. For several of our targets that were less than 30 Myr old, the lower mass limit was as low as a Jupiter mass, well into the high mass planet region. Results of the entire survey include the proper motion verification of five low-mass stellar companions, two brown dwarfs (HR7329B and TWA5B) and one possible brown dwarf binary (Gl 577B/C).Comment: 11 figures, accepted by A
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