5,925 research outputs found
The Mommy Trek? Working Womens Choices
A quarter century after Felice Schwartz urged companies to craft policies accommodating parental responsibilities or risk losing talented women, many highly educated women are leaving traditional careers. Is the 21st century workplace experiencing a Mommy Trek foreshadowed by Schwartzs recommendation for a Mommy Track? What choices are todays working women making? Do things turn out as planned? Will Family Friendly programs keep women from leaving? This paper presents results of a study conducted to explore the Mommy Trek
Click Here For Reality: Enhancing Student Engagement
This paper presents three initiatives designed to advance undergraduate learning outcomes by enhancing student engagement through active, reality-based learning. The Team Challenge, Management Consultant Simulation, and Bookstore Adventure are described
Apprentice Watch: Learning Through Reality TV
The Apprentice attracts younger viewers in record number. Most of today’s college students fall within that range. This paper presents pedagogy created to use The Apprentice in business school teaching. 
Teaching Generation Y College Students: Three Initiatives
This paper presents three initiatives created to teach Generation Y students in an undergraduate general education class. The Performance Contract, Investigative Report, and Class Game Show are described
Spatially and Spectrally Resolved Hydrogen Gas within 0.1 AU of T Tauri and Herbig Ae/Be Stars
We present near-infrared observations of T Tauri and Herbig Ae/Be stars with
a spatial resolution of a few milli-arcseconds and a spectral resolution of
~2000. Our observations spatially resolve gas and dust in the inner regions of
protoplanetary disks, and spectrally resolve broad-linewidth emission from the
Brackett gamma transition of hydrogen gas. We use the technique of
spectro-astrometry to determine centroids of different velocity components of
this gaseous emission at a precision orders of magnitude better than the
angular resolution. In all sources, we find the gaseous emission to be more
compact than or distributed on similar spatial scales to the dust emission. We
attempt to fit the data with models including both dust and Brackett
gamma-emitting gas, and we consider both disk and infall/outflow morphologies
for the gaseous matter. In most cases where we can distinguish between these
two models, the data show a preference for infall/outflow models. In all cases,
our data appear consistent with the presence of some gas at stellocentric radii
of ~0.01 AU. Our findings support the hypothesis that Brackett gamma emission
generally traces magnetospherically driven accretion and/or outflows in young
star/disk systems.Comment: 48 pages, including 17 figures. Accepted for publication by Ap
Teaching Workplace Skills Through Integrative Exercises
This paper presents a set of three integrative exercises created to help college students develop workplace skills through simulation. Interviewing, listening, providing feedback, setting goals, empowering, coaching, managing change, handling conflict, and making decisions are clustered and modeled at intervals that synthesize course learning
A VLA Survey For Faint Compact Radio Sources in the Orion Nebula Cluster
We present Karl G. Janksy Very Large Array (VLA) 1.3 cm, 3.6 cm, and 6 cm
continuum maps of compact radio sources in the Orion Nebular Cluster. We
mosaicked 34 square arcminutes at 1.3 cm, 70 square arcminutes at 3.6 cm and
109 square arcminutes at 6 cm, containing 778 near-infrared detected YSOs and
190 HST-identified proplyds (with significant overlap between those
characterizations). We detected radio emission from 175 compact radio sources
in the ONC, including 26 sources that were detected for the first time at these
wavelengths. For each detected source we fit a simple free-free and dust
emission model to characterize the radio emission. We extrapolate the free-free
emission spectrum model for each source to ALMA bands to illustrate how these
measurements could be used to correctly measure protoplanetary disk dust masses
from sub-millimeter flux measurements. Finally, we compare the fluxes measured
in this survey with previously measured fluxes for our targets, as well as four
separate epochs of 1.3 cm data, to search for and quantify variability of our
sources.Comment: 13 pages, 6 figures, 4 tables, ApJ, in pres
First L-band Interferometric Observations of a Young Stellar Object: Probing the Circumstellar Environment of MWC 419
We present spatially-resolved K- and L-band spectra (at spectral resolution R
= 230 and R = 60, respectively) of MWC 419, a Herbig Ae/Be star. The data were
obtained simultaneously with a new configuration of the 85-m baseline Keck
Interferometer. Our observations are sensitive to the radial distribution of
temperature in the inner region of the disk of MWC 419. We fit the visibility
data with both simple geometric and more physical disk models. The geometric
models (uniform disk and Gaussian) show that the apparent size increases
linearly with wavelength in the 2-4 microns wavelength region, suggesting that
the disk is extended with a temperature gradient. A model having a power-law
temperature gradient with radius simultaneously fits our interferometric
measurements and the spectral energy distribution data from the literature. The
slope of the power-law is close to that expected from an optically thick disk.
Our spectrally dispersed interferometric measurements include the Br gamma
emission line. The measured disk size at and around Br gamma suggests that
emitting hydrogen gas is located inside (or within the inner regions) of the
dust disk.Comment: Accepted for publication in Ap
Protoplanetary Disk Masses from Radiative Transfer Modeling: A Case Study in Taurus
Measuring the masses of protoplanetary disks is crucial for understanding
their planet-forming potential. Typically, dust masses are derived from
(sub-)millimeter flux density measurements plus assumptions for the opacity,
temperature, and optical depth of the dust. Here we use radiative transfer
models to quantify the validity of these assumptions with the aim of improving
the accuracy of disk dust mass measurements. We first carry out a controlled
exploration of disk parameter space. We find that the disk temperature is a
strong function of disk size, while the optical depth depends on both disk size
and dust mass. The millimeter-wavelength spectral index can be significantly
shallower than the naive expectation due to a combination of optical depth and
deviations from the Rayleigh-Jeans regime. We fit radiative transfer models to
the spectral energy distributions (SEDs) of 132 disks in the Taurus-Auriga
region using a Markov chain Monte Carlo approach. We used all available data to
produce the most complete SEDs used in any extant modeling study. We perform
the fitting twice: first with unconstrained disk sizes and again imposing the
disk size--brightness relation inferred for sources in Taurus. This constraint
generally forces the disks to be smaller, warmer, and more optically thick.
From both sets of fits, we find disks to be 1--5 times more massive than
when derived using (sub-)millimeter measurements and common assumptions. With
the uncertainties derived from our model fitting, the previously measured dust
mass--stellar mass correlation is present in our study but only significant at
the 2 level.Comment: 28 pages, 13 figures, accepted for publication in A
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