855 research outputs found
Which retroviral Gag proteins utilize crm1 nuclear export system throughout their lifecycle? [abstract]
Academic and Civic Outcomes of African American Graduates of Historically Black and Historically White High Schools
The purpose of this study was to examine how high school experience impacts adult outcomes for African Americans across time given changes in academic, social, and political climates. This research is very much needed to help the African American community identify what factors are related to individuals giving back to their community through civic engagement in order to promote self-sufficiency within the African American community. The study design explored the role of these factors by comparing the personal high school experience, long-term outcomes of civic engagement and academic attainment as well as racial identity perceptions of African American graduates of historically Black high schools (HBHSs) and historically White high schools (HWHSs). Statistically, 2x3 Analysis of Variance (ANOVA) designs were run to compare group outcomes by school type and graduation year. Overall results indicated that African American graduates did not differ significantly on long-term outcomes or personal racial identity as a function of school type, but HBHS graduates reported more positive school experiences compared to HWHS graduates. Study results provide support for the contribution of Historically Black Institutions in secondary education with implications for identification of factors related to academic attainment and civic engagement.Doctor of Philosoph
Farm Resiliency Education for At-Risk Coastal Areas in the Chesapeake Bay
The Virginia Institute of Marine Science (VIMS) in collaboration with its partners, the Land Trust Alliance, Sustainable Chesapeake, and The Nature Conservancy, explored and refined questions critical for advising and guiding landowners who farm within coastal areas that are vulnerable to sea level rise and saltwater intrusion, and ultimately, loss of arable cropland in the Chesapeake Bay watershed. While the questions posed are those that agricultural experts across the coastal zones are struggling with, this effort focused on identifying the current state of the science and informational gaps; building current, best professional guidance for landowner conservation program choices; and developing a research framework for improving our understanding and building capacity to maximize, incentivize, and secure ecosystem services beyond food provision at the farm-scape scale
Limited native plant regeneration in novel, exotic-dominated forests on Hawai’i
Ecological invasions are a major driver of global environmental change. When invasions are frequent and prolonged, exotic species can become dominant and ultimately create novel ecosystem types. These ecosystems are now widespread globally. Recent evidence from Puerto Rico suggests that exotic-dominated forests can provide suitable regeneration sites for native species and promote native species abundance, but this pattern has been little explored elsewhere. We surveyed 46 sites in Hawai’i to determine whether native species occurred in the understories of exotic-dominated forests. Native trees smaller than 10 cm in diameter were absent in 28 of the 46 sites and rare in the others. Natives were never the dominant understory species; in fact, they accounted for less than 10% of understory basal area at all but six sites, and less than 4% on average. Sites with native species in the understory tended to be on young lava substrate lacking human disturbance, and were mostly located close to intact, native-dominated forest stands. Even where we found some native species, however, most were survivors of past exotic encroachment into native forest, rather than products of active recolonization by native species. In contrast with successional trajectories in Puerto Rico, Hawaii\u27s exotic-dominated forests can emerge, via invasion, without human disturbance and native Hawaiian plants are largely unable to colonize them once they appear. We suggest that a wide diversity of growth strategies among the exotic species on Hawai’i may limit the opportunities for native plants to colonize exotic-dominated forests
Probing Distant Massive Black Holes with LISA
Idealized models are used to illustrate the potential of the Laser
Interferometer Space Antenna (LISA) as a probe of the largely unknown
population of cosmologically-distant Massive Black Holes (MBHs) and as a tool
to measure their masses with unprecedented accuracy. The models suggest that
LISA will most efficiently probe a MBH population of lower mass than the one
found in bright quasars and nearby galactic nuclei. The mass spectrum of these
MBHs could constrain formation scenarios for high-redshift, low-mass galaxies.Comment: 8 pages, 5 figures, accepted for publication in Class. Quant. Gravity
(4th LISA Symposium Special Issue
Modeling the spatial distribution of African buffalo (Syncerus caffer) in the Kruger National Park, South Africa
The population density of wildlife reservoirs contributes to disease transmission risk for domestic animals. The objective of this study was to model the African buffalo distribution of the Kruger National Park. A secondary objective was to collect field data to evaluate models and determine environmental predictors of buffalo detection. Spatial distribution models were created using buffalo census information and archived data from previous research. Field data were collected during the dry (August 2012) and wet (January 2013) seasons using a random walk design. The fit of the prediction models were assessed descriptively and formally by calculating the root mean square error (rMSE) of deviations from field observations. Logistic regression was used to estimate the effects of environmental variables on the detection of buffalo herds and linear regression was used to identify predictors of larger herd sizes. A zero-inflated Poisson model produced distributions that were most consistent with expected buffalo behavior. Field data confirmed that environmental factors including season (P = 0.008), vegetation type (P = 0.002), and vegetation density (P = 0.010) were significant predictors of buffalo detection. Bachelor herds were more likely to be detected in dense vegetation (P = 0.005) and during the wet season (P = 0.022) compared to the larger mixed-sex herds. Static distribution models for African buffalo can produce biologically reasonable results but environmental factors have significant effects and therefore could be used to improve model performance. Accurate distribution models are critical for the evaluation of disease risk and to model disease transmission
Validity of the Paper Pull Test for Strength in Patients with Hallux Valgus
Introduction/Purpose: The purpose of this study was to explore validity of the paper pull test (PPT) to assess hallux flexion strength and function in persons with hallux valgus (HV). The following hypotheses were tested: 1) The PPT is valid for inferring 1st MTP flexion strength and heel rise (HR) performance (e.g. heel height). 2) A specified threshold of force during the PPT can be identified that discriminates patients with HV. 3) Muscle activity (abductor hallucis [AH], flexor hallucis brevis [FHB]), in patients with HV will be distinct from controls across three tasks: 1) PPT, 2) lowering phase of a HR, and 3) rising phase of a HR
From Drips to Tsunamis: Planning for Disasters in Your Library
Disasters strike every area of any country and affect libraries, large or small. From a water leak
to something big like an earthquake, hurricane or fire, libraries need to have a plan of action for
an effective response. Our panel discussion included librarians who have survived disasters
along with others who live in potentially hazardous areas. We discussed disaster plans from a
number of institutions of different sizes, collections and budgets as well as providing some best
practices and resources for creating or updating your own plan
The SCUBA Half Degree Extragalactic Survey (SHADES) - III : Identification of radio and mid-infrared counterparts to submillimetre galaxies
Peer reviewe
Submillimetre Constraints on Hyper-Extremely Red Objects in the Subaru Deep Field
We have mapped the submillimetre wavelength continuum emission from the
Subaru Deep Field (SDF) at 450 and 850 microns with the Submillimetre
Common-User Bolometer Array (SCUBA) detector on the James Clerk Maxwell
Telescope (JCMT). The near-IR image of the SDF is one of the deepest near-IR
images available and contains four `hyper extremely red objects' (HEROs). These
data allow us to test the connection between `extremely red objects' (EROs)
found in IR surveys and the population of bright submillimetre sources found
with SCUBA. We present a weak measurement of the average flux of the four
K-band selected HEROs of 1.15 (+/-0.46) mJy, which fails to support the
hypothesis that HEROs should be bright SCUBA sources. Our data are consistent
with the HEROs being objects with SEDs like that of Arp220 out to z~1.7,
however, the extinction in the HEROs must be about 1 magnitude greater in the
J-band than is the case for Arp220 and they would need to be 1.7 times as
luminous as Arp220. On the other hand, an evolutionary model of elliptical
galaxies at z~2-3 in a dusty starburst phase is also in agreement with the
submillimetre data, as was originally proposed for the HEROs.Comment: 7 pages, 5 figures, accepted for publication in MNRAS July 5th, 200
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