ABSTRACT
We homogeneously analyse ∼3.2 × 105 photometric measurements for ∼1100 transit light curves belonging to 17 exoplanet hosts. The photometric data cover 16 years (2004–2019) and include ...amateur and professional observations. Old archival light curves were reprocessed using up-to-date exoplanetary parameters and empirically debiased limb-darkening models. We also derive self-consistent transit and radial-velocity fits for 13 targets. We confirm the non-linear transit timing variation (TTV) trend in the WASP-12 data at a high significance, and with a consistent magnitude. However, Doppler data reveal hints of a radial acceleration of about −7.5 ± 2.2 m s−1 yr−1, indicating the presence of unseen distant companions, and suggesting that roughly 10 per cent of the observed TTV was induced via the light-travel (or Roemer) effect. For WASP-4, a similar TTV trend suspected after the recent TESS observations appears controversial and model dependent. It is not supported by our homogeneous TTV sample, including 10 ground-based EXPANSION light curves obtained in 2018 simultaneously with TESS. Even if the TTV trend itself does exist in WASP-4, its magnitude and tidal nature are uncertain. Doppler data cannot entirely rule out the Roemer effect induced by possible distant companions.
ABSTRACT
In 2021 BL Lacertae underwent an extraordinary activity phase, which was intensively followed by the Whole Earth Blazar Telescope (WEBT) Collaboration. We present the WEBT optical data in ...the BVRI bands acquired at 36 observatories around the world. In mid-2021 the source showed its historical maximum, with R = 11.14. The light curves display many episodes of intraday variability, whose amplitude increases with source brightness, in agreement with a geometrical interpretation of the long-term flux behaviour. This is also supported by the long-term spectral variability, with an almost achromatic trend with brightness. In contrast, short-term variations are found to be strongly chromatic and are ascribed to energetic processes in the jet. We also analyse the optical polarimetric behaviour, finding evidence of a strong correlation between the intrinsic fast variations in flux density and those in polarization degree, with a time delay of about 13 h. This suggests a common physical origin. The overall behaviour of the source can be interpreted as the result of two mechanisms: variability on time-scales greater than several days is likely produced by orientation effects, while either shock waves propagating in the jet, or magnetic reconnection, possibly induced by kink instabilities in the jet, can explain variability on shorter time-scales. The latter scenario could also account for the appearance of quasi-periodic oscillations, with periods from a few days to a few hours, during outbursts, when the jet is more closely aligned with our line of sight and the time-scales are shortened by relativistic effects.
Abstract Objectives To evaluate the psychopathological profile and the incidence of major depressive disorders in consecutive women attending a Menopause Clinic. Methods Women attending outpatient ...menopause clinic at Filippo del Ponte Hospital in Varese (Italy), referring to the centre from 1 March to 30 April 2005, were invited to fill up a specific questionnaire while waiting for the visit. The questionnaire included demographics and history (e.g. current or past use of antidepressant drugs); symptoms check list (SCL-90-R); Beck depression inventory (BDI). Results Sixty-four women were enrolled to the study. On the SCL-90-R, “somatic” symptoms cluster was the most frequent. Patients diagnosed as depressed using the Beck depression inventory (BDI) were 18 (28.1%). Thirteen (70%) of currently depressed women presented a positive history of depressive disorders. The analysis of depressed women according to previous depressive disorders revealed higher scores for women with positive history in both scales. Depressed patients have a significantly lower mean age compared to non-depressed patients (53.3 ± 6.2 years versus 57.33 ± 4.9 years, p = 0.023). Conclusions Our preliminary data show a high correlation between a history of depressive disorder and recurrence of depression in the menopausal period. Perimenopause seems to be a higher risk period for the development of a depressive disease compared to menopausal status. The somatization cluster warrants further investigation.
Oral DHEA administration to patients with hypoadrenalism, in addition to glucocorticoid and mineralcorticoid replacement, may improve both well-being and hormonal/metabolic parameters. Twenty ...patients (13 men, 7 women, 26-76 yr, 11 with Addison's disease, 9 with central hypoadrenalism) were recruited in a placebo-controlled, randomized study. Hormone levels, carbohydrate and lipid parameters, bone metabolism, body composition and psychological parameters were evaluated at baseline and after treatment with DHEA 50 mg/day or placebo for 4 months. After 4 months of DHEA administration, serum DHEAS levels raised both in men (from 0.71+/-0.18 to 8.28+/-1.66 micropmol/l, p<0.005) and in women (from 0.25+/-0.07 to 5.65+/-1.93 micromol/l, p<0.05). Only in hypoadrenal women an increase in testosterone (T; from 0.4+/-0.1 to 1.45+/-0.26 nmol/l, p<0.05) and androstenedione (A; from 0.86+/-0.34 to 2.05+/-0.29 nmol/l, p<0.05) levels was observed. In men no significant modifications in T and 17-hydroxyprogesterone (17-OHP) levels were found, whereas serum SHBG significantly decreased. As far as the metabolic parameters are concerned, only in patients with Addison's disease a significant decrease in total cholesterol and in low-density lipoproteins after 4 months of DHEA administration was found. No changes in glucose metabolism and insulin sensitivity were observed. In basal conditions, mean serum osteocalcin (OC) was normal and significantly decreased after DHEA treatment. A significant reduction in body fat mass percentage (BF%) after DHEA administration was observed. As far as well-being is concerned, DHEA replacement did not cause any relevant variation of subjective health scales and sexuality in both sexes. Our study confirms that DHEA may be beneficial for female patients with hypoadrenalism, mainly in restoring androgen levels. Concerning the health status, more sensitive and specific instruments to measure the effects of DHEA treatment could be necessary.
Context. In 2009, the Sun and the Earth passed through the equatorial plane of Jupiter and therefore the orbital planes of its main satellites. It was the equinox on Jupiter. This occurrence made ...mutual occultations and eclipses between the satellites possible. Experience has shown that the observations of such events provide accurate astrometric data able to bring new information on the dynamics of the Galilean satellites. Observations are made under the form of photometric measurements, but need to be made through the organization of a worldwide observation campaign maximizing the number and the quality of the data obtained. Aims. This work focuses on processing the complete database of photometric observations of the mutual occultations and eclipses of the Galilean satellites of Jupiter made during the international campaign in 2009. The final goal is to derive new accurate astrometric data. Methods. We used an accurate photometric model of mutual events adequate with the accuracy of the observation. Our original method was applied to derive astrometric data from photometric observations of mutual occultations and eclipses of the Galilean satellites of Jupiter. Results. We processed the 457 lightcurves obtained during the international campaign of photometric observations of the Galilean satellites of Jupiter in 2009. Compared with the theory, for successful observations, the r.m.s. of O–C residuals are equal to 45.8 mas and 81.1 mas in right ascension and declination, respectively; the mean O–C residuals are equal to –2 mas and –9 mas in right ascension and declination, respectively, for mutual occultations; and –6 mas and +1 mas in right ascension and declination, respectively, for mutual eclipses.
We developed a dedicated statistical test for a massive detection of spot- and facula-crossing anomalies in multiple exoplanetary transit light curves, based on the frequentist p-value thresholding. ...This test was used to augment our algorithmic pipeline for transit light curves analysis. It was applied to 1598 amateur and professional transit observations of 26 targets being monitored in the EXPANSION project. We detected 109 statistically significant candidate events revealing a roughly 2:1 asymmetry in favor of spots-crossings over faculae-crossings. Although some candidate anomalies likely appear non-physical and originate from systematic errors, such asymmetry between negative and positive events should indicate a physical difference between the frequency of star spots and faculae. Detected spot-crossing events also reveal positive correlation between their amplitude and width, possibly due to spot size correlation. However, the frequency of all detectable crossing events appears just about a few per cent, so they cannot explain excessive transit timing noise observed for several targets.
This paper presents 2109 times of minima for 965 objects acquired by 59 members and cooperating observers of the Variable Star and Exoplanet Section of the Czech Astronomical Society (B.R.N.O. ...Observing project).These observations were submitted to the website of the Variable Star and Exoplanet Section of the Czech Astronomical Society between November 2016 and March 2018.
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