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Addressing School Dropout in Texas: A Summary for Administrators and Policymakers of "Dropout Prevention: A Practice Guide"
This booklet summarizes the information from: Dropout Prevention: A Practice Guide, available on the Institute of Education Sciences web site at http://ies.ed.gov/ncee/wwc.Educatio
The oral microbiome and adverse pregnancy outcomes.
Significant evidence supports an association between periodontal pathogenic bacteria and preterm birth and preeclampsia. The virulence properties assigned to specific oral pathogenic bacteria, for example, Fusobacterium nucleatum, Porphyromonas gingivalis, Filifactor alocis, Campylobacter rectus, and others, render them as potential collaborators in adverse outcomes of pregnancy. Several pathways have been suggested for this association: 1) hematogenous spread (bacteremia) of periodontal pathogens; 2) hematogenous spread of multiple mediators of inflammation that are generated by the host and/or fetal immune response to pathogenic bacteria; and 3) the possibility of oral microbial pathogen transmission, with subsequent colonization, in the vaginal microbiome resulting from sexual practices. As periodontal disease is, for the most part, preventable, the medical and dental public health communities can address intervention strategies to control oral inflammatory disease, lessen the systemic inflammatory burden, and ultimately reduce the potential for adverse pregnancy outcomes. This article reviews the oral, vaginal, and placental microbiomes, considers their potential impact on preterm labor, and the future research needed to confirm or refute this relationship
Discovery of a supernova associated with GRB 031203: SMARTS Optical-Infrared Lightcurves from 0.2 to 92 days
Optical and infrared monitoring of the afterglow site of gamma-ray burst
(GRB) 031203 has revealed a brightening source embedded in the host galaxy,
which we attribute to the presence of a supernova (SN) related to the GRB ("SN
031203"). We present details of the discovery and evolution of SN 031203 from
0.2 to 92 days after the GRB, derived from SMARTS consortium photometry in I
and J bands. A template type Ic lightcurve, constructed from SN 1998bw
photometry, is consistent with the peak brightness of SN 031203 although the
lightcurves are not identical. Differential astrometry reveals that the SN, and
hence the GRB, occurred less than 300 h_71^-1 pc (3-sigma) from the apparent
galaxy center. The peak of the supernova is brighter than the optical afterglow
suggesting that this source is intermediate between a strong GRB and a
supernova.Comment: 11 pages, 3 figures, submitted to ApJ Letter
Ab Initio Liquid Hydrogen Muon Cooling Simulations with ELMS in ICOOL
This paper presents new theoretical results on the passage of muons through
liquid hydrogen which have been confirmed in a recent experiment. These are
used to demonstrate that muon bunches may be compressed by ionisation cooling
more effectively than suggested by previous calculations.
Muon cooling depends on the differential cross section for energy loss and
scattering of muons. We have calculated this cross section for liquid H2 from
first principles and atomic data, avoiding traditional assumptions. Thence, 2-D
probability maps of energy loss and scattering in mm-scale thicknesses are
derived by folding, and stored in a database. Large first-order correlations
between energy loss and scattering are found for H2, which are absent in other
simulations. This code is named ELMS, Energy Loss & Multiple Scattering. Single
particle trajectories may then be tracked by Monte Carlo sampling from this
database on a scale of 1 mm or less. This processor has been inserted into the
cooling code ICOOL. Significant improvements in 6-D muon cooling are predicted
compared with previous predictions based on GEANT. This is examined in various
geometries. The large correlation effect is found to have only a small effect
on cooling. The experimental scattering observed for liquid H2 in the MUSCAT
experiment has recently been reported to be in good agreement with the ELMS
prediction, but in poor agreement with GEANT simulation.Comment: 6 pages, 3 figure
Every Day With Your Girl
Black and white photo of five men looking at camerahttps://scholarsjunction.msstate.edu/cht-sheet-music/12400/thumbnail.jp
Structured evaluation of virtual environments for special-needs education
This paper describes the development of a structured approach to evaluate experiential and communication virtual learning environments (VLEs) designed specifically for use in the education of children with severe learning difficulties at the Shepherd special needs school in Nottingham, UK. Constructivist learning theory was used as a basis for the production of an evaluation framework, used to evaluate the design of three VLEs and how they were used by students with respect to this learning theory. From an observational field study of student-teacher pairs using the VLEs, 18 behaviour categories were identified as relevant to five of the seven constructivist principles defined by Jonassen (1994). Analysis of student-teacher behaviour was used to provide support for, or against, the constructivist principles. The results show that the three VLEs meet the constructivist principles in very different ways and recommendations for design modifications are put forward
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