41 research outputs found
OGLE-LMC-ECL-11893 : the discovery of a long-period eclipsing binary with a circumstellar disk
No full textS.D. is supported by "the Strategic Priority Research Program-The Emergence of Cosmological Structures" of the Chinese Academy of Sciences (grant No. XDB09000000). The OGLE project has received funding from the European Research Council under the European Community's Seventh Framework Programme (FP7/20072013)/ERC grant agreement No. 246678 to A.U. M.D., R.F.J., K.H., R.A.S., C.S., and Y.T. are supported by NPRP grant NPRP-09-476-1-78 from the Qatar National Research Fund (a member of Qatar Foundation). D.M.B.'s contribution to this publication was made possible by NPRP grant # X-019-1-006 from the Qatar National Research Fund (a member of Qatar Foundation). C.S. has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 268421.We report the serendipitous discovery of a disk-eclipse system OGLE-LMC-ECL-11893. The eclipse occurs with a period of 468 days, a duration of about 15 days, and a deep (up to ΔmI 1.5), peculiar, and asymmetric profile. A possible origin of such an eclipse profile involves a circumstellar disk. The presence of the disk is confirmed by the H-α line profile from the follow-up spectroscopic observations, and the star is identified as Be/Ae type. Unlike the previously known disk-eclipse candidates, the eclipses of OGLE-LMC-ECL-11893 retain the same shape throughout the span of ∼17 yr (13 orbital periods), indicating no measurable orbital precession of the disk.Peer reviewe
Genetic Problems, Diagnosis, and Cardiovascular Manifestations of Loeys-Dietz Syndrome
No full textLoeys-Dietz Syndrome (LDS) is an autosomal dominant connective tissue disorder with multisystem involvement of wide spectrum, found to be associated with transforming growth factor-β pathway. LDS is characterized by craniofacial, skeletal, cutaneous, vascular abnormalities along with aortic aneurysm and aortic dissection contributing to mortality and morbidity at a young age. Therefore, timely diagnosis and intervention in patients with LDS is vital. Several gene mutations have been described as contributing factors of LDS, causing widespread and aggressive vascular disease. Based on these gene mutations, 5 types of LDS have been described so far. Besides aortic aneurysm and dissection, some of the other cardiac manifestations of LDS involve cardiomyopathy, valvular abnormality, atrial fibrillation, patent ductus arteriosus, atrial septal defects, etc. Routine imaging of patients\u27 vasculatures and aggressive medical and surgical management are key factors in managing patients with LDS
Sleep Disorders and Coronary Artery Disease
No full textA sufficient amount and quality sleep is vital components for maintaining optimal physical wellbeing, cognition, and cardiovascular health. Normal sleep provides us with a low physiological stress that promotes overall cardiovascular health. Sleep disorders are common, and often goes undiagnosed. Patients with sleep disorders, commonly suffer from poor quality of life due to the poor quality of their sleep. They are associated with adverse effects on cardiovascular health, such as coronary artery disease. Sleep disorders discussed in this review article include sleep-disordered breathing (obstructive sleep apnea and central sleep apnea), insomnia and restless leg syndrome. Sleep disorders primarily have four acute adverse cardiovascular consequences. First, intermittent hypoxemia-reoxygenation in arterial blood along with PCO 2 fluctuation; second is excessive arousals; third, decreased parasympathetic and increased sympathetic tone; fourth being the large pressure swings in the intrathoracic cavity. This review focuses on classifications, and prevalence of the three major classes of sleep disorders, and the evidence to date on the association between these sleep disorders and coronary artery disease
Baxdrostat: An Aldosterone Synthase Inhibitor for the Treatment of Systemic Hypertension
No full textSystemic hypertension remains one of the leading cause of morbidity and mortality in the United States and throughout the world. Baxdrostat (CIN-107), a new drug developed by Roche is a selective aldosterone synthase inhibitor that is being evaluated as one of the potential treatments for hypertension, especially in patients with drug treatment-resistant hypertension. An increased level of aldosterone is associated with inflammation, systemic hypertension, and organ fibrosis, contributing to adverse cardiovascular events. A phase 2 trial, BrigHTN, showed promising results in demonstrating the efficacy of baxdrostat, where The HALO (efficacy and safety of baxdrostat in patients with uncontrolled hypertension) trial did not demonstrate any blood pressure-lowering benefit of baxdrostat when compared with the placebo. Several additional studies are now underway to evaluate the effectiveness of baxdrostat as an anti-hypertensive agent
FAST RISE OF "NEPTUNE-SIZE" PLANETS (4-8 R-circle plus) FROM P similar to 10 TO similar to 250 DAYS-STATISTICS OF KEPLER PLANET CANDIDATES UP TO similar to 0.75AU
No full textWe infer the period (P) and size (R-p) distribution of Kepler transiting planet candidates with R-p >= 1 R-circle plus and P < 250 days hosted by solar-type stars. The planet detection efficiency is computed by using measured noise and the observed time spans of the light curves for similar to 120,000 Kepler target stars. We focus on deriving the shape of planet periods and radius distribution functions. We find that for orbital periods P > 10 days, the planet frequency dN(p)/d logP for "Neptune-size" planets (R-p = 4-8 R-circle plus) increases with period as alpha P0.7+0.1. In contrast, dN(p)/dlogP for "super-Earth-size" (2-4 R-circle plus) as well as "Earth-size" (1-2 R-circle plus) planets are consistent with a nearly flat distribution as a function of period (alpha P-0.11 +/- 0.05 and alpha P-0.10 +/- 0.12, respectively), and the normalizations are remarkably similar (within a factor of similar to 1.5 at 50 days). Planet size distribution evolves with period, and generally the relative fractions for big planets (similar to 3-10 R-circle plus) increase with period. The shape of the distribution function is not sensitive to changes in the selection criteria of the sample. The implied nearly flat or rising planet frequency at long periods appears to be in disagreement with the sharp decline at similar to 100 days in planet frequency for low-mass planets (planet mass m(p) < 30 M-circle plus) recently suggested by the HARPS survey. Within 250 days, the cumulative frequencies for Earth-size and super-Earth-size planets are remarkably similar (similar to 28% and 25%), while Neptune-size and Jupiter-size planets are similar to 7% and similar to 3%, respectively. Amajor potential uncertainty arises from the unphysical impact parameter distribution of the candidates.Astronomy & AstrophysicsSCI(E)31ARTICLE1null77
Hydroxychloroquine, QTc prolongation and risk of torsades de pointes
No full textHydroxychloroquine (HCQ) is a common medication used for the treatment of rheumatic diseases. As a result of its widespread use during COVID-19, there are increasing concerns about its cardiotoxicity. HCQ is known to cause QTc prolongation, and its long-term use has been associated with cardiomyopathy and conduction abnormalities. Despite reports of ventricular arrhythmia in COVID-19 patients taking HCQ, there have been reassuring data in approved indications. HCQ has been in use for several decades with a good safety profile. In addition to better disease control and prevention of flares, it is associated with decreased risk of cardiovascular diseases. But given its small risk of cardiotoxicity, clinicians should be aware of this effect and monitor patients for developing cardiac symptoms
Detecting extrasolar asteroid belts through their microlensing signatures
No full textWe propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called 'pseudo-caustics', regions in the source plane where the magnification exhibits a finite but discontinuous jump. These features allow such systems to generate distinctive signatures in the microlensing light curves for a wide range of belt configurations, with source trajectories as far as tenths of the Einstein ring radius from the centre of the lens. Sample light curves for a range of asteroid belt parameters are presented. In the near future, space-based microlensing surveys like WFIRST, which will have the power of detecting per cent-level changes in microlensing light curves even with subminute exposure times, may be able to discover extrasolar asteroid belts with masses of the order of an earth mass.Strategic Priority Research Program 'The Emergence of Cosmological Structures of the Chinese Academy of Sciences' [XDB09000000]; NSFC [11573003]; centre for High Performance Computing at the University of UtahSCI(E)ARTICLE22010-201746
WARM JUPITERS NEED CLOSE "FRIENDS" FOR HIGH-ECCENTRICITY MIGRATION-A STRINGENT UPPER LIMIT ON THE PERTURBER'S SEPARATION
No full textWe propose a stringent observational test on the formation of warm Jupiters (gas-giant planets with 10 days less than or similar to P less than or similar to 100 days) by high-eccentricity (high-e) migration mechanisms. Unlike hot Jupiters, the majority of observed warm Jupiters have pericenter distances too large to allow efficient tidal dissipation to induce migration. To access the close pericenter required for migration during a Kozai-Lidov cycle, they must be accompanied by a strong enough perturber to overcome the precession caused by general relativity, placing a strong upper limit on the perturber's separation. For a warm Jupiter at a similar to 0.2AU, a Jupiter-mass (solar-mass) perturber is required to be less than or similar to 3AU (less than or similar to 30AU) and can be identified observationally. Among warm Jupiters detected by radial velocities (RVs), greater than or similar to 50% (5 out of 9) with large eccentricities (e greater than or similar to 0.4) have known Jovian companions satisfying this necessary condition for high-e migration. In contrast, less than or similar to 20% (3 out of 17) of the low-e (e less than or similar to 0.2) warm Jupiters have detected additional Jovian companions, suggesting that high-e migration with planetary perturbers may not be the dominant formation channel. Complete, long-term RV follow-ups of the warm-Jupiter population will allow a firm upper limit to be put on the fraction of these planets formed by high-e migration. Transiting warm Jupiters showing spin-orbit misalignments will be interesting to apply our test. If the misalignments are solely due to high-e migration as commonly suggested, we expect that the majority of warm Jupiters with low-e (e less than or similar to 0.2) are not misaligned, in contrast with low-e hot Jupiters.Astronomy & AstrophysicsSCI(E)7ARTICLE1null78
Acute Coronary Syndrome Due to Coronary Vasospasm: A Case Report
No full textCoronary vasospasm can lead to decreased cardiac perfusion and result in acute coronary syndrome. Here is a case of a 49-year-old man presented to the emergency department with epigastric pain and nausea with normal initial electrocardiogram. However, 6 h later, the patient experienced severe chest pain prompting a repeat electrocardiogram demonstrating inferior ST-segment elevation with troponin I levels peaked at 1.2 ng/ml (normal range: 0.00–0.02 ng/ml). Coronary angiography revealed angiographic stenosis in the left circumflex territory of a left dominant system which resolved with intracoronary nitroglycerin administration indicating ischemia with nonobstructive coronary arteries secondary to coronary vasospasm. He was discharged on isosorbide mononitrate and amlodipine therapy and had no recurrence of symptoms during follow-up
