11,100 research outputs found
Bridges
This entry discusses the linguistic (prosodic) features of the Ancient Greek poetic phenomenon of the metrical bridge, a position in a line of verse where a word division is either disallowed or strongly disfavored
Influence of shear reinforcement corrosion on the performance of under-reinforced concrete beams
The in-service performance of reinforced concrete beams can be severely affected through cor-rosion of the steel reinforcement when it becomes subjected to harsh corrosive environments containing chlo-rides and carbon dioxide. In such instances, corrosion is likely to occur in the steel reinforcement, with the expansive nature of the corrosion products likely to induce cracking and spalling of the concrete. A loss of structural integrity (stiffness) will occur and this can severely influence the serviceability of the member. The purpose of this paper is to investigate the relationship between degree of corrosion and loss of stiffness in corrosion damaged under-reinforced concrete beams. Beams (100mm x 150mm cross section) were subjected to accelerated corrosion in the laboratory and subsequently tested in flexure to failure. The paper reports on the results of these tests and relates the degree of corrosion in the main steel to the percentage loss in stiffness in the concrete beams
Somatic mutation load of estrogen receptor-positive breast tumors predicts overall survival: an analysis of genome sequence data.
Breast cancer is one of the most commonly diagnosed cancers in women. While there are several effective therapies for breast cancer and important single gene prognostic/predictive markers, more than 40,000 women die from this disease every year. The increasing availability of large-scale genomic datasets provides opportunities for identifying factors that influence breast cancer survival in smaller, well-defined subsets. The purpose of this study was to investigate the genomic landscape of various breast cancer subtypes and its potential associations with clinical outcomes. We used statistical analysis of sequence data generated by the Cancer Genome Atlas initiative including somatic mutation load (SML) analysis, Kaplan-Meier survival curves, gene mutational frequency, and mutational enrichment evaluation to study the genomic landscape of breast cancer. We show that ER(+), but not ER(-), tumors with high SML associate with poor overall survival (HR = 2.02). Further, these high mutation load tumors are enriched for coincident mutations in both DNA damage repair and ER signature genes. While it is known that somatic mutations in specific genes affect breast cancer survival, this study is the first to identify that SML may constitute an important global signature for a subset of ER(+) tumors prone to high mortality. Moreover, although somatic mutations in individual DNA damage genes affect clinical outcome, our results indicate that coincident mutations in DNA damage response and signature ER genes may prove more informative for ER(+) breast cancer survival. Next generation sequencing may prove an essential tool for identifying pathways underlying poor outcomes and for tailoring therapeutic strategies
Molecular weight effects on chain pull-out fracture of reinforced polymeric interfaces
Using Brownian dynamics, we simulate the fracture of polymer interfaces
reinforced by diblock connector chains. We find that for short chains the
interface fracture toughness depends linearly on the degree of polymerization
of the connector chains, while for longer chains the dependence becomes
. Based on the geometry of initial chain configuration, we propose a
scaling argument that accounts for both short and long chain limits and
crossover between them.Comment: 5 pages, 3 figure
Pathogenic, Molecular, and Immunological Properties of a Virus Associated with Sea Turtle Fibropapillomatosis. Phase II : Viral Pathogenesis and Development of Diagnostic Assays
Research conducted under this RWO from July 1, 1997 through June 30, 2000 has
provided important new information about the pathogenesis, virology, and
immunology of marine turtle fibropapillomatosis. In particular, we have provided
strong evidence for the association of a herpesvirus with fibropapillomatosis of the
green turtle,Chelonia mydas, and the loggerhead turtle, Caretta caretta, in Florida. In
addition we have provided new evidence for the absence of papillomaviruses from
sea turtle fibropapillomas. Although unsuccessful, important new attempts were made
to cultivate the FP-associated herpesvirus in vitro in collaboration with the National
Wildlife Health Center. During this period of time, we completed publication of the first
comprehensive description of the comparative pathology and pathogenesis of
experimentally induced and spontaneous fibropapillomas of green turtles (Chelonia
mydas). We initiated innovative studies on the persistence of a Chelonian
herpesviruses in the marine environment demonstrating for the first time that the
environmental survivability of Chelonian herpesviruses makes them real threats to
marine turtle health. Finally, we explored development of a serological assay for FP
using synthetic herpesvirus peptides and developed methodologies for detection of
antibodies to LETV [Iung-eye-trachea virus] a disease-associated herpesvirus of the
green turtle, Chelonia mydas.. This last initiative is ongoing and will further our efforts
to develop specific immunological assays for the FP-associated herpesvirus and FP. (17 page document
Tunneling conductance in Superconductor/Ferromagnet junctions: a self consistent approach
We evaluate the tunneling conductance of clean Ferromomagnet/Superconductor
junctions via a fully self-consistent numerical solution of the microscopic
Bogoliubov-DeGennes equations. We present results for a relevant range of
values of the Fermi wavevector mismatch (FWM), the spin polarization, and the
interfacial scattering strength. For nonzero spin polarization, the conductance
curves vary nonmonotonically with FWM. The FWM dependence of the
self-consistent results is stronger than that previously found in
non-self-consistent calculations, since, in the self-consistent case, the
effective scattering potential near the interface depends on the FWM. The
dependence on interfacial scattering is monotonic. These results confirm that
it is impossible to characterize both the the FWM and the interfacial
scattering by a single effective parameter and that analysis of experimental
data via the use of such one-parameter models is unreliable.Comment: 12 pages, including 8 figure
Influence of steel reinforcement corrosion on the stiffness of simply supported concrete beams
The in-service performance of reinforced concrete beams can be severely affected through cor-rosion of the steel reinforcement when it becomes subjected to harsh corrosive environments containing chlo-rides and carbon dioxide. In such instances, corrosion is likely to occur in the steel reinforcement, with the expansive nature of the corrosion products likely to induce cracking and spalling of the concrete. A loss of structural integrity (stiffness) will occur and this can severely influence the serviceability of the member. The purpose of this paper is to investigate the relationship between degree of corrosion and loss of stiffness in corrosion damaged under-reinforced concrete beams. Beams (100mm x 150mm cross section) were subjected to accelerated corrosion in the laboratory and subsequently tested in flexure to failure. The paper reports on the results of these tests and relates the degree of corrosion in the main steel to the percentage loss in stiffness in the concrete beams
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