128 research outputs found
The Relationship between Growth Scores and the Overall Observation Ratings for Teachers in a Public School System in Tennessee
The purpose of this study was to investigate the relationship between the TVAAS growth score given by the Tennessee Department of Education and the overall Tennessee Educator Assessment Model (TEAM) observation rating for teachers in grades 3 through 8. The participating county public school system for this study is located in Northeast Tennessee. Participants were teachers in the school system teaching Math, English/Language Arts, Science, and Social Studies in grades 3 through 8 in 10 elementary schools, 6 middle schools, and 2 K-8 schools. Specifically, this research examined the relationship between the TEAM observation scores and overall TVAAS growth score given to the teacher from the Tennessee Department of Education based upon yearly-standardized test scores. Research reinforced mixed views about the validity and purpose of teacher evaluation systems and the use of Tennessee Value-Added Assessment System. Five research questions guided this study and quantitative data were analyzed using a Pearson correlation, one-way MANOVAs and a one-way ANOVA. Results indicated a moderate positive relationship between a teacher’s TEAM observation score and the TVAAS growth score given by the Tennessee Department of Education
The Relationship between Growth Scores and the Overall Observation Ratings for Teachers in a Public School System in Tennessee
Abstract is available to download
CfAIR2: Near Infrared Light Curves of 94 Type Ia Supernovae
CfAIR2 is a large homogeneously reduced set of near-infrared (NIR) light
curves for Type Ia supernovae (SN Ia) obtained with the 1.3m Peters Automated
InfraRed Imaging TELescope (PAIRITEL). This data set includes 4607 measurements
of 94 SN Ia and 4 additional SN Iax observed from 2005-2011 at the Fred
Lawrence Whipple Observatory on Mount Hopkins, Arizona. CfAIR2 includes JHKs
photometric measurements for 88 normal and 6 spectroscopically peculiar SN Ia
in the nearby universe, with a median redshift of z~0.021 for the normal SN Ia.
CfAIR2 data span the range from -13 days to +127 days from B-band maximum. More
than half of the light curves begin before the time of maximum and the coverage
typically contains ~13-18 epochs of observation, depending on the filter. We
present extensive tests that verify the fidelity of the CfAIR2 data pipeline,
including comparison to the excellent data of the Carnegie Supernova Project.
CfAIR2 contributes to a firm local anchor for supernova cosmology studies in
the NIR. Because SN Ia are more nearly standard candles in the NIR and are less
vulnerable to the vexing problems of extinction by dust, CfAIR2 will help the
supernova cosmology community develop more precise and accurate extragalactic
distance probes to improve our knowledge of cosmological parameters, including
dark energy and its potential time variation.Comment: 31 pages, 15 figures, 10 tables. Accepted to ApJS. v2 modified to
more closely match journal versio
A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a
The merging neutron star gravitational wave event GW170817 has been observed
throughout the entire electromagnetic spectrum from radio waves to
-rays. The resulting energetics, variability, and light curves are
shown to be consistent with GW170817 originating from the merger of two neutron
stars, in all likelihood followed by the prompt gravitational collapse of the
massive remnant. The available -ray, X-ray and radio data provide a
clear probe for the nature of the relativistic ejecta and the non-thermal
processes occurring within, while the ultraviolet, optical and infrared
emission are shown to probe material torn during the merger and subsequently
heated by the decay of freshly synthesized -process material. The simplest
hypothesis that the non-thermal emission is due to a low-luminosity short
-ray burst (sGRB) seems to agree with the present data. While low
luminosity sGRBs might be common, we show here that the collective prompt and
multi-wavelength observations are also consistent with a typical, powerful sGRB
seen off-axis. Detailed follow-up observations are thus essential before we can
place stringent constraints on the nature of the relativistic ejecta in
GW170817.Comment: 9 pages, 5 figures, accepted to ApJ Letter
The Calibration of the Swift/UVOT Optical Observations: A Recipe for Photometry
Swift/UVOT has the capability to provide critical insight into the physics of
the early afterglows of gamma-ray bursts (GRBs). But without precise
calibration of the UVOT to standard photometric systems, it is impossible to
leverage late- time, ground-based follow-up data to the early-time UVOT
observations. In this paper, we present a calibration of the Swift/UVOT
photometry to the standard Johnson UBV system for the UVOT UBV filters,and a
step-by-step photometry recipe for analyzing these data. We base our analysis
on aperture photometry performed on the ground-based and UVOT observations of
the local standard stars in the fields of supernovae (SNe) 2005am and 2005cf,
and a number of Landolt standard stars.We find that the optimal photometry
aperture radius for UVOT data is small (2".5 for unbinned data,3".0 for 2X2
binned data),and show that the coincidence- loss (C-loss) correction is
important even for relatively faint magnitudes (mag 16 to 19). Based on a
theoretically motivated model,we fit the C-loss correction with two parameters,
the photometric zero point (ZP) and the saturation magnitude (m_inf), and
derive tight constraints for both parameters [sigma(ZP) = 0.01 mag and
sigma(m_inf) = 0.02 mag)].We find that the color term correction is not
necessary for the UVOT B and V filters,but is necessary for the U filter for
blue objects [(U - V) < 0.4 mag]. We also apply our calibration results to the
UVOT observations of GRB 050603. There is a scatter of ~0.04--0.08 mag in our
final UVOT photometry, the cause of which is unclear, but may be partly due to
the spatial variation in the pixel sensitivity of the UVOT detector.Comment: Accepted for publication in PASP (2006 Jan issue). Significantly
improved version with many more standard stars. A high resolution version can
be found at http://astron.berkeley.edu/~weidong/uvot_calib.ps.g
Kaposi Sarcoma-Associated Herpesvirus Glycoprotein H Is Indispensable for Infection of Epithelial, Endothelial, and Fibroblast Cell Types
Kaposi sarcoma-associated herpesvirus (KSHV) is an emerging pathogen and is the causative infectious agent of Kaposi sarcoma and two malignancies of B cell origin. To date, there is no licensed KSHV vaccine. Development of an effective vaccine against KSHV continues to be limited by a poor understanding of how the virus initiates acute primary infection in vivo in diverse human cell types. The role of glycoprotein H (gH) in herpesvirus entry mechanisms remains largely unresolved. To characterize the requirement for KSHV gH in the viral life cycle and in determination of cell tropism, we generated and characterized a mutant KSHV in which expression of gH was abrogated. Using a bacterial artificial chromosome containing a complete recombinant KSHV genome and recombinant DNA technology, we inserted stop codons into the gH coding region. We used electron microscopy to reveal that the gH-null mutant virus assembled and exited from cells normally, compared to wild-type virus. Using purified virions, we assessed infectivity of the gH-null mutant in diverse mammalian cell types in vitro. Unlike wild-type virus or a gH-containing revertant, the gH-null mutant was unable to infect any of the epithelial, endothelial, or fibroblast cell types tested. However, its ability to infect B cells was equivocal and remains to be investigated in vivo due to generally poor infectivity in vitro. Together, these results suggest that gH is critical for KSHV infection of highly permissive cell types, including epithelial, endothelial, and fibroblast cells. IMPORTANCE All homologues of herpesvirus gH studied to date have been implicated in playing an essential role in viral infection of diverse permissive cell types. However, the role of gH in the mechanism of KSHV infection remains largely unresolved. In this study, we generated a gH-null mutant KSHV and provided evidence that deficiency of gH expression did not affect viral particle assembly or egress. Using the gH-null mutant, we showed that gH was indispensable for KSHV infection of epithelial, endothelial, and fibroblast cells in vitro. This suggests that gH is an important target for the development of a KSHV prophylactic vaccine to prevent initial viral infection
Kaposi Sarcoma-associated Herpesvirus Glycoprotein H is Indispensable for Infection of Epithelial, Endothelial, and Fibroblast Cell Types
Kaposi sarcoma-associated herpesvirus (KSHV) is an emerging pathogen and is the causative infectious agent of Kaposi sarcoma and two malignancies of B cell origin. To date, there is no licensed KSHV vaccine. Development of an effective vaccine against KSHV continues to be limited by a poor understanding of how the virus initiates acute primary infection in vivo in diverse human cell types. The role of glycoprotein H (gH) in herpesvirus entry mechanisms remains largely unresolved. To characterize the requirement for KSHV gH in the viral life cycle and in determination of cell tropism, we generated and characterized a mutant KSHV in which expression of gH was abrogated. Using a bacterial artificial chromosome containing a complete recombinant KSHV genome and recombinant DNA technology, we inserted stop codons into the gH coding region. We used electron microscopy to reveal that the gH-null mutant virus assembled and exited from cells normally, compared to wild-type virus. Using purified virions, we assessed infectivity of the gH-null mutant in diverse mammalian cell types in vitro Unlike wild-type virus or a gH-containing revertant, the gH-null mutant was unable to infect any of the epithelial, endothelial, or fibroblast cell types tested. However, its ability to infect B cells was equivocal, and remains to be investigated in vivo due to generally poor infectivity in vitro Together, these results suggest that gH is critical for KSHV infection of highly permissive cell types including epithelial, endothelial, and fibroblasts.
MPORTANCE: All homologues of herpesvirus gH studied to date have been implicated in playing an essential role in viral infection of diverse permissive cell types. However, the role of gH in the mechanism of KSHV infection remains largely unresolved. In this study, we generated a gH-null mutant KSHV and provided evidence that deficiency of gH expression did not affect viral particle assembly or egress. Using the gH-null mutant, we showed that gH was indispensable for KSHV infection of epithelial, endothelial, and fibroblast cells in vitro. This suggests that gH is an important target for the development of a KSHV prophylactic vaccine to prevent initial viral infection
Type IIb Supernova SN 2011dh: Spectra and Photometry from the Ultraviolet to the Near-Infrared
We report spectroscopic and photometric observations of the Type IIb SN
2011dh obtained between 4 and 34 days after the estimated date of explosion
(May 31.5 UT). The data cover a wide wavelength range from 2,000 Angstroms in
the UV to 2.4 microns in the NIR. Optical spectra provide line profiles and
velocity measurements of HI, HeI, CaII and FeII that trace the composition and
kinematics of the SN. NIR spectra show that helium is present in the atmosphere
as early as 11 days after the explosion. A UV spectrum obtained with the STIS
reveals that the UV flux for SN 2011dh is low compared to other SN IIb. The HI
and HeI velocities in SN 2011dh are separated by about 4,000 km/s at all
phases. We estimate that the H-shell of SN 2011dh is about 8 times less massive
than the shell of SN 1993J and about 3 times more massive than the shell of SN
2008ax. Light curves (LC) for twelve passbands are presented. The maximum
bolometric luminosity of erg s occurred
about 22 days after the explosion. NIR emission provides more than 30% of the
total bolometric flux at the beginning of our observations and increases to
nearly 50% of the total by day 34. The UV produces 16% of the total flux on day
4, 5% on day 9 and 1% on day 34. We compare the bolometric light curves of SN
2011dh, SN 2008ax and SN 1993J. The LC are very different for the first twelve
days after the explosions but all three SN IIb display similar peak
luminosities, times of peak, decline rates and colors after maximum. This
suggests that the progenitors of these SN IIb may have had similar compositions
and masses but they exploded inside hydrogen shells that that have a wide range
of masses. The detailed observations presented here will help evaluate
theoretical models for this supernova and lead to a better understanding of SN
IIb.Comment: 23 pages, 14 figures, 9 tables, accepted by Ap
An FDA bioinformatics tool for microbial genomics research on molecular characterization of bacterial foodborne pathogens using microarrays
<p>Abstract</p> <p>Background</p> <p>Advances in microbial genomics and bioinformatics are offering greater insights into the emergence and spread of foodborne pathogens in outbreak scenarios. The Food and Drug Administration (FDA) has developed a genomics tool, ArrayTrack<sup>TM</sup>, which provides extensive functionalities to manage, analyze, and interpret genomic data for mammalian species. ArrayTrack<sup>TM</sup> has been widely adopted by the research community and used for pharmacogenomics data review in the FDA’s Voluntary Genomics Data Submission program. </p> <p>Results</p> <p>ArrayTrack<sup>TM</sup> has been extended to manage and analyze genomics data from bacterial pathogens of human, animal, and food origin. It was populated with bioinformatics data from public databases such as NCBI, Swiss-Prot, KEGG Pathway, and Gene Ontology to facilitate pathogen detection and characterization. ArrayTrack<sup>TM</sup>’s data processing and visualization tools were enhanced with analysis capabilities designed specifically for microbial genomics including flag-based hierarchical clustering analysis (HCA), flag concordance heat maps, and mixed scatter plots. These specific functionalities were evaluated on data generated from a custom Affymetrix array (FDA-ECSG) previously developed within the FDA. The FDA-ECSG array represents 32 complete genomes of <it>Escherichia coli</it> and<it> Shigella.</it> The new functions were also used to analyze microarray data focusing on antimicrobial resistance genes from <it>Salmonella</it> isolates in a poultry production environment using a universal antimicrobial resistance microarray developed by the United States Department of Agriculture (USDA).</p> <p>Conclusion</p> <p>The application of ArrayTrack<sup>TM</sup> to different microarray platforms demonstrates its utility in microbial genomics research, and thus will improve the capabilities of the FDA to rapidly identify foodborne bacteria and their genetic traits (e.g., antimicrobial resistance, virulence, etc.) during outbreak investigations. ArrayTrack<sup>TM</sup> is free to use and available to public, private, and academic researchers at <url>http://www.fda.gov/ArrayTrack</url>. </p
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