3,167 research outputs found
Moving I`iwi (Vestiaria coccinea) as a Surrogate for Future Translocations of Endangered `Akohekohe (Palmeria dolei)
Translocations often play an important role in the recovery of endangered species. To
assess feasibility for translocation of endangered `Akohekohe (Palmeria dolei), we
conducted an experimental translocation of I`iwi (Vestiaria coccinea) from east to west
Maui. Mist-netting, veterinary screening of candidate birds, and helicopter transport of
healthy I`iwi were successful, resulting in no injuries or mortalities. Translocated birds
were assigned to two types of release. Hard release birds were radio tagged and released
on the day of translocation. In contrast, soft release birds were held in large cages for 7
days and fed artificial nectar. During holding soft release I`iwi feeding rates, fecal
production, and mass were monitored. Soft release birds suffered 33% mortality during
the holding period. At the end of the holding period, soft release survivors were outfitted
with a radio transmitter and released. All translocated I`iwi were followed by radio
telemetry for an average of 21 days. Once released, soft release birds showed higher
rates of movement, possibly reflecting conflict with established hard released I`iwi. Our
results suggest that translocation efforts for wild `Akohekohe will be successful if hard
release protocols are followed
Finding the Center of Mass of a Soft Spring
This article shows how to use calculus to find the center of mass position of
a soft cylindrical helical spring that is suspended vertically. The spring is
non-uniformly stretched by the action of gravity. A general expression for the
vertical position of the center of mass is obtained.Comment: LaTeX, 7 pages, 2 figures. Minor changes to agree with published
versio
Christian University Teacher Education Graduates and Perceptions of Parent Collaboration: An Exploratory Study
Effective collaboration between families and schools is an important factor when developing high quality education programs. When schools and families work together, children, families, schools, and communities all benefit. Using an online survey of students who completed teacher certification programs at two Christian universities, this study seeks to understand the way that completers from two teacher preparation programs, both at Christian universities, interact with parents and encourage collaboration and involvement. The research findings and implications for future research are discussed
A baseline assessment of migratory and resident bird use of a prairie restoration site in eastern Washington
Prairies, and other types of grassland ecosystems, have suffered some of the most profound losses worldwide, due to anthropogenic factors such as fossil fuel extraction, agriculture, and climate change. Likewise, organisms inhabiting grassland ecosystems have become extirpated across much of their historical range, not the least of which has been a 50% decline in grassland birds since the 1960s. In response to losses of intact prairie in eastern Washington, a 120-ac site has been established on the EWU campus to regenerate native prairie and monitor changes in the ecosystem as native plants recolonize and replace non-natives. Because birds are an important indicator species of ecosystem health, the goal of our research was to estimate baseline abundance and diversity of birds at the prairie restoration site before restoration takes place. We also assessed bird abundance and diversity at a small, intact prairie remnant 20 mi north of the EWU campus to compare current bird use of the restoration site with that of an intact prairie system. We assessed bird abundance and bird diversity using the line-transect method. We established one transect at each site, and counted all birds seen or heard within 50 meters of the transects. Our findings will provide a baseline of knowledge about how and when birds will begin to reinhabit the EWU restoration site and inform future restoration efforts on the benefits and outcomes of restoring native grasslands locally, and worldwide
A report on the nonlinear squeezed states and their non-classical properties of a generalized isotonic oscillator
We construct nonlinear squeezed states of a generalized isotonic oscillator
potential. We demonstrate the non-existence of dual counterpart of nonlinear
squeezed states in this system. We investigate statistical properties exhibited
by the squeezed states, in particular Mandel's parameter, second-order
correlation function, photon number distributions and parameter in
detail. We also examine the quadrature and amplitude-squared squeezing effects.
Finally, we derive expression for the -parameterized quasi-probability
distribution function of these states. All these information about the system
are new to the literature.Comment: Accepted for publication in J. Phys. A: Math. Theo
Transcriptome Sequencing Demonstrates that Human Papillomavirus Is Not Active in Cutaneous Squamous Cell Carcinoma
β-Human papillomavirus (β-HPV) DNA is present in some cutaneous squamous cell carcinomas (cuSCCs), but no mechanism of carcinogenesis has been determined. We used ultra-high-throughput sequencing of the cancer transcriptome to assess whether papillomavirus transcripts are present in these cancers. In all, 67 cuSCC samples were assayed for β-HPV DNA by PCR, and viral loads were measured with type-specific quantitative PCR. A total of 31 SCCs were selected for whole transcriptome sequencing. Transcriptome libraries were prepared in parallel from the HPV18-positive HeLa cervical cancer cell line and HPV16-positive primary cervical and periungual SCCs. Of the tumors, 30% (20/67) were positive for β-HPV DNA, but there was no difference in β-HPV viral load between tumor and normal tissue (P=0.310). Immunosuppression and age were significantly associated with higher viral load (P=0.016 for immunosuppression; P=0.0004 for age). Transcriptome sequencing failed to identify papillomavirus expression in any of the skin tumors. In contrast, HPV16 and HPV18 mRNA transcripts were readily identified in primary cervical and periungual cancers and HeLa cells. These data demonstrate that papillomavirus mRNA expression is not a factor in the maintenance of cuSCCs
Comparative Analysis of Tandem Repeats from Hundreds of Species Reveals Unique Insights into Centromere Evolution
Centromeres are essential for chromosome segregation, yet their DNA sequences
evolve rapidly. In most animals and plants that have been studied, centromeres
contain megabase-scale arrays of tandem repeats. Despite their importance, very
little is known about the degree to which centromere tandem repeats share
common properties between different species across different phyla. We used
bioinformatic methods to identify high-copy tandem repeats from 282 species
using publicly available genomic sequence and our own data. The assumption that
the most abundant tandem repeat is the centromere DNA was true for most species
whose centromeres have been previously characterized, suggesting this is a
general property of genomes. Our methods are compatible with all current
sequencing technologies. Long Pacific Biosciences sequence reads allowed us to
find tandem repeat monomers up to 1,419 bp. High-copy centromere tandem repeats
were found in almost all animal and plant genomes, but repeat monomers were
highly variable in sequence composition and in length. Furthermore,
phylogenetic analysis of sequence homology showed little evidence of sequence
conservation beyond ~50 million years of divergence. We find that despite an
overall lack of sequence conservation, centromere tandem repeats from diverse
species showed similar modes of evolution, including the appearance of higher
order repeat structures in which several polymorphic monomers make up a larger
repeating unit. While centromere position in most eukaryotes is epigenetically
determined, our results indicate that tandem repeats are highly prevalent at
centromeres of both animals and plants. This suggests a functional role for
such repeats, perhaps in promoting concerted evolution of centromere DNA across
chromosomes
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