Katie J Johnston

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Prenatal stress influences neural and behavioral sexual differentiation in rodents. Male offspring of stressed pregnancies show reduced masculine-typical characteristics and increased feminine-typical characteristics, whereas female offspring show the opposite pattern, reduced feminine-typical and increased masculine-typical characteristics. These outcomes(More)
Vega, the second brightest star in the northern hemisphere, serves as a primary spectral type standard. Although its spectrum is dominated by broad hydrogen lines, the narrower lines of the heavy elements suggested slow to moderate rotation, giving confidence that the ground-based calibration of its visible spectrum could be safely extrapolated into the(More)
We report successful fitting of a Roche model, with a surface temperature gradient following the von Zeipel gravity darkening law, to observations of Altair made with the Navy Prototype Optical Interferometer. We confirm the claim by Ohishi, Nordgren, & Hutter that Altair displays an asym-metric intensity distribution due to rotation, the first such(More)
We present direct measurements of the limb-darkened intensity profiles of the late-type giant stars HR 5299, HR 7635, and HR 8621 obtained with the Navy Prototype Optical Interferometer (NPOI) at the Lowell Observatory. A triangle of baselines with lengths of 18.9 m, 22.2 m, and 37.5 m was used. We utilized squared visibility amplitudes beyond the first(More)
The Navy Precision Optical Interferometer (NPOI) has two purposes: wide angle precise astrometry and high-resolution imaging, both at visible wavelengths. It operates with up to six 12-cm diameter apertures simultaneously, with baseline lengths (distances between array elements) from 16 m to 79 m, and disperses the combined light into 16 spectral channels.(More)
Integrated-optic, astronomical, two-beam and three-beam, interferometric combiners have been designed and fabricated for operation in the L band (3 µm – 4 µm) for the first time. The devices have been realized in titanium-indiffused, x-cut lithium niobate substrates, and on-chip electro-optic fringe scanning has been demonstrated. White light fringes were(More)
We have used the Very Large Array, linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 19 radio stars in the International Celestial Reference Frame (ICRF). The positions of these stars were directly linked to the positions of distant quasars through phase referencing observations. The positions of the ICRF(More)
The first section of this bibliography includes papers presented at conferences and meetings by RLE faculty, staff and students during 1987, and is in chronological order by the month the conference was held. Reprints of papers may be obtained by contacting the authors directly. Sections 30.2 and 30.3 are alphabetical listings by author of journal articles(More)
  • T Joseph, W Lazio, E B Waltman, F D Ghigo, R L Fiedler, R S Foster +1 other
  • 2001
We present light curves for 149 sources monitored with the Green Bank Interferometer. The light curves are at two radio frequencies (approximately 2.5 and 8.2 GHz) and range from 3 to 15 yrs in length, covering the interval 1979–1996, and have a typical sampling of one flux density measurement every 2 days. We have used these light curves to conduct various(More)