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Teenage pregnancy and parenting : national problem, local solution.
The purpose of this dissertation is to look at the problem of teen pregnancy and parenting on a national, state and local level. When dealing with the local level, the study will deal with the Adolescent Parenting Program (APP), Cambridge, Massachusetts. The first purpose of the study was to look at the research and literature on the topic of teen pregnancy and parenting to better understand the extent, magnitude, and issues surrounding this problem. The goal of the study was to contact participants of APP at Cambridge Rindge and Latin. The study utilized an author developed questionnaire and one-to-one interviews to gather research on the APP. With the results of the questionnaires and the interviews, many factors were found to have impacted on these pregnant and parenting teens, including family constellation, marital status of the parents of the respondents, marital status of the respondents, age dating was initiated, age sex was initiated, fear of sexually transmitted diseases, methods of birth control, age at birth of first child, planned/unplanned pregnancy, completing high school, employment, and relationship with baby\u27s father. The first purpose of the study was to look at the problem of pregnant and parenting teens at a national, state, and local level. Research substantiated the need to help pregnant and parenting teens and this confirmed the need for the APP in Cambridge. The second and most important part of the study was to determine whether or not the APP was effective. The questionnaires and interviews confirmed this. The third purpose of the study was to determine whether Cambridge needed to do more in the area of teen pregnancy and parenting. There are various area that need improvement, but finances are a major issue. The fourth purpose of the study was to determine whether the APP and the First Steps Day Care could be replicated in other communities. There has been a great deal of interest demonstrated in these two programs, but there must be a commitment of not only money, but also of people to make the programs work
Laboratory Testing the Layer Oriented Wavefront Sensor for the Multiconjugate Adaptive optics Demonstrator
The Multiconjugate Adaptive optics Demonstrator (MAD) for ESO-Very Large
Telescopes (VLT) will demonstrate on sky the MultiConjugate Adaptive Optics
(MCAO) technique. In this paper the laboratory tests relative to the first
preliminary acceptance in Europe of the Layer Oriented (LO) Wavefront Sensor
(WFS) for MAD will be described: the capabilities of the LO approach have been
checked and the ability of the WFS to measure phase screens positioned at
different altitudes has been experimented. The LO WFS was opto-mechanically
integrated and aligned in INAF - Astrophysical Observatory of Arcetri before
the delivering to ESO (Garching) to be installed on the final optical bench.
The LO WFS looks for up to 8 reference stars on a 2arcmin Field of View and up
to 8 pyramids can be positioned where the focal spot images of the reference
stars form, splitting the light in four beams. Then two objectives conjugated
at different altitudes simultaneously produce a quadruple pupil image of each
reference star.Comment: 12 pages,14 figures, Proceeding of Spie Conference "Advances in
Adaptive Optics II", Orlando 200
The opto-mechanical alignment procedure of the VLT Survey Telescope
The VLT Survey Telescope is a f/5.5 modified Ritchey-Chretien imaging
telescope, which is being installed at the ESO-Paranal Observatory. It will
provide a one square degree corrected field of view to perform survey-projects
in the wavelength range from UV to I band. In this paper we describe the
opto-mechanical alignment procedure of the 2.61m primary mirror, the secondary
and correctors lenses onto the mechanical structure of the telescope. The
alignment procedure does not rely on the mechanical precision of the mirrors.
It will be achieved using ad-hoc alignment tools, described in the paper, which
allows the spatial determination of optical axes (and focuses where necessary)
of the optical components with respect to the axis defined by the rotation of a
laser beam mounted on the instrument bearing.Comment: 10 pages, 10 figures, Proceeding 773357 of the SPIE Conference
"Ground-based and Airborne Telescopes III", Sunday 27 June 2010, San Diego,
California, US
Is There a Place in the World for Zoos? / Another View of Zoos
We human animals make rapid technological and cultural advancements because we have the ability to pass definitive information to succeeding generations. But we also accept too much from the past without challenge. The good, the bad, and the indifferent are muddled together, accumulating in layers that smother each succeeding age. Cultural mores ranging from the silly to the profane, from charming to dangerous, clutter our world. They exist only because, as the British are wont to say, “We have always done things this way.” One very troubling example is the public zoological parks found in almost every city: they are fundamentally unchanged from the first public zoo that opened in The Regent’s Park in London in 1828. Although significant modifications have taken place since then, particularly recently, for the most part, zoos continue to do things the way they have done them for almost two centuries. An objective reevaluation is long overdue
Is There a Place in the World for Zoos? / Another View of Zoos
We human animals make rapid technological and cultural advancements because we have the ability to pass definitive information to succeeding generations. But we also accept too much from the past without challenge. The good, the bad, and the indifferent are muddled together, accumulating in layers that smother each succeeding age. Cultural mores ranging from the silly to the profane, from charming to dangerous, clutter our world. They exist only because, as the British are wont to say, “We have always done things this way.” One very troubling example is the public zoological parks found in almost every city: they are fundamentally unchanged from the first public zoo that opened in The Regent’s Park in London in 1828. Although significant modifications have taken place since then, particularly recently, for the most part, zoos continue to do things the way they have done them for almost two centuries. An objective reevaluation is long overdue
An update of the on-sky performance of the Layer-Oriented wave-front sensor for MAD
The Multi-conjugate Adaptive optics Demonstrator, MAD, successfully
demonstrated on sky the MCAO technique both in Layer Oriented and Star Oriented
modes. As results of the Guaranteed Time Observations in Layer Oriented mode
quality astronomy papers have been published. In this paper we concentrate on
the instrumentation issues and technical aspects which stay behind this
success.Comment: 12 pages, 10 figures, Proceedings of the SPIE conference "Adaptive
Optics Systems II", 27 June 2010, San Diego, California, US
Simulations of ELT-GMCAO performance for deep field observations
The Global-Multi Conjugated Adaptive Optics (GMCAO) approach offers an
alternative way to correct an adequate scientific Field of View (FoV) using
only natural guide stars (NGSs) to extremely large ground-based telescopes.
Thus, even in the absence of laser guide stars, a GMCAO-equipped ELT-like
telescope can achieve optimal performance in terms of Strehl Ratio (SR),
retrieving impressive results in studying star-poor fields, as in the cases of
the deep field observations. The benefits and usability of GMCAO have been
demonstrated by studying 6000 mock high redshift galaxies in the Chandra Deep
Field South region. However, a systematic study simulating observations in
several portions of the sky is mandatory to have a robust statistic of the
GMCAO performance. Technical, tomographic and astrophysical parameters,
discussed here, are given as inputs to GIUSTO, an IDL-based code that estimates
the SR over the considered field, and the results are analyzed with statistical
considerations. The best performance is obtained using stars that are
relatively close to the Scientific FoV; therefore, the SR correlates with the
mean off-axis position of NGSs, as expected, while their magnitude plays a
secondary role. This study concludes that the SRs correlate linearly with the
galactic latitude, as also expected. Because of the lack of natural guide stars
needed for low-order aberration sensing, the GMCAO confirms as a promising
technique to observe regions that can not be studied without the use of laser
beacons. It represents a robust alternative way or a risk mitigation strategy
for laser approaches on the ELTs.Comment: 18 pages, 10 figures, accepted for publication on PAS
Numerical control matrix rotation for the LINC-NIRVANA Multi-Conjugate Adaptive Optics system
LINC-NIRVANA will realize the interferometric imaging focal station of the
Large Binocular Telescope. A double Layer Oriented multi-conjugate adaptive
optics system assists the two arms of the interferometer, supplying high order
wave-front correction. In order to counterbalance the field rotation,
mechanical derotation for the two ground wave-front sensors, and optical
derotators for the mid-high layers sensors fix the positions of the focal
planes with respect to the pyramids aboard the wave-front sensors. The
derotation introduces pupil images rotation on the wavefront sensors: the
projection of the deformable mirrors on the sensor consequently change. The
proper adjustment of the control matrix will be applied in real-time through
numerical computation of the new matrix. In this paper we investigate the
temporal and computational aspects related to the pupils rotation, explicitly
computing the wave-front errors that may be generated.Comment: 6 pages, 2 figures, presented at SPIE Symposium "Astronomical
Telescopes and Instrumentation'' conference "Adaptive Optics Systems
II'',Sunday 27 June 2010, San Diego, California, US
Hierarchichal-segmented AO in order to attain wide field compensation in the visible on an 8m class telescope
We describe the preliminary optimized layout for a partially optimized
concept of an optical-8m class VLT-like 2x2 segmented camera where each channel
is assisted by an equivalent of an MCAO system where the ground layer
correction is commonly employed while the high altitude ones is performed in an
open-loop fashion. While we derive the basic relationships among the Field of
View and attainable correction with a pre-defined choice for the hardware, we
discuss sky coverage and wavefront sensing issues employing natural and
artificial references, involving the latest stateof-the-art in the development
of wavefront sensing. We show that a flexible approach allow for a compensated
Field of View that is variable and can be properly tuned matching the current
turbulence situation and the requirement in term of quality of the
compensation. A preliminary description of the overall optomechanical package
is given as well along with a rough estimates of the efforts required to
translates such a concept into reality.Comment: 6 pages, 4 figures, in AO4ELT5 Proceeding
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