We present simultaneous infrared and X-ray observations of the Galactic microquasar GRS 1915+105 using the Palomar 5 m telescope and Rossi X-Ray Timing Explorer on 1998 July 10 UT. Over the course of 5 hr, we observed six faint infrared (IR) flares with peak amplitudes of approximately 0.3-0.6 mJy and durations of approximately 500-600 s. These flares are associated with X-ray soft-dip/soft-flare cycles, as opposed to the brighter IR flares associated with X-ray hard-dip/soft-flare cycles seen in 1997 August by Eikenberry et al. Interestingly, the IR flares begin before the X-ray oscillations, implying an "outside-in" origin of the IR/X-ray cycle. We also show that the quasi-steady IR excess in 1997 August is due to the pileup of similar faint flares. We discuss the implications of this flaring behavior for understanding jet formation in microquasars.
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http://dx.doi.org/10.1086/312559 | DOI Listing |
Retin Cases Brief Rep
January 2025
New England Eye Center, Tufts Medical Center, Boston, MA.
Purpose: To describe a case of stellate multiform amelanotic choroidopathy (SMACH) with focal hyperfluorescence on indocyanine green angiography (ICGA).
Methods: Case report.
Results: A 19-year-old Caucasian woman was seen for an asymptomatic choroidal lesion.
AMB Express
November 2024
Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, PO Box 68, Hadayek Shoubra, Cairo, 11241, Egypt.
JBMR Plus
October 2024
Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 22529 Hamburg, Germany.
Materials (Basel)
May 2024
Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarina 7, 87-100 Torun, Poland.
This study introduces a novel approach to synthesising a three-dimensional (3D) micro-nanostructured amorphous biosilica. The biosilica is coated with cerium oxide nanoparticles obtained from laboratory-grown unicellular photosynthetic algae (diatoms) doped metabolically with cerium. This unique method utilises the ability of diatom cells to absorb cerium metabolically and deposit it on their silica exoskeleton as cerium oxide nanoparticles.
View Article and Find Full Text PDFPhysiol Behav
July 2024
Faculty of Medical Science, University of Tehran, Tehran, Iran.
Postural change from supine or sitting to standing up leads to displacement of 300 to 1000 mL of blood from the central parts of the body to the lower limb, which causes a decrease in venous return to the heart, hence decrease in cardiac output, causing a drop in blood pressure. This may lead to falling down, syncope, and in general reducing the quality of daily activities, especially in the elderly and anyone suffering from nervous system disorders such as Parkinson's or orthostatic hypotension (OH). Among different modalities to study brain function, functional near-infrared spectroscopy (fNIRS) is a neuroimaging method that optically measures the hemodynamic response in brain tissue.
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