Showing 1721 - 1730 of 2039 Items

Study of D0 decays into final states with a 0 or

Date: 1991-01-01

Creator: K. Kinoshita

F. M. Pipkin

M. Procario

Richard Wilson

J., Wolinski

D. Xiao

Y. Zhu

R. Ammar

P. Baringer

D. Coppage

R. Davis

P. Haas

M. Kelly

N. Kwak

Ha Lam

S. Ro

Y. Kubota

J. K. Nelson

D. Perticone

R. Poling

S. Schrenk

G. Crawford

R. Fulton

T. Jensen

D. R. Johnson

H. Kagan

R. Kass

R. Malchow

F. Morrow

J. Whitmore

P. Wilson

Access: Open access

We have made measurements of decay modes of neutral D mesons into exclusive final states containing photons using data collected with the CLEO detector at the Cornell Electron Storage Ring. We report observation of D0'K-+-+0 (charge conjugates are implicit), and present new measurements of the branching ratios for D0'K-+0, D0'K0+0-, D0'K00, K*0, and D0'K0. Where possible, results are compared with theoretical predictions for two-body D0 decays. © 1991 The American Physical Society.


Unusual decay modes of D0 and D+ mesons

Date: 1991-01-01

Creator: R. Ammar

P. Baringer

D. Coppage

R. Davis

P., Haas

M. Kelly

N. Kwak

H. Lam

S. Ro

Y. Kubota

J. K. Nelson

D. Perticone

R. Poling

S. Schrenk

G. Crawford

R. Fulton

T. Jensen

D. Johnson

H. Kagan

R. Kass

R. Malchow

F. Marrow

J. Whitmore

P. Wilson

D. Bortoletto

D. N. Brown

J. Dominick

R. L. McIlwain

D. H. Miller

M. Modesitt

C. R. Ng

Access: Open access

CLEO has measured decay modes of the D0 and D+ into final states consisting of K's, s, K0's and 0's, using data taken with the CLEO detector at the Cornell Electron Storage Ring. We report new results on the decays of D0's into 4, K-K+-+, 0K+K-, 0K+-, K0K-+, 3KS0 and 0 together with some of their resonant substructure. We also present the first observation of the decay D00K+ and give limits on the doubly-Cabibbo-suppressed decays of the D0 into K+- and K+-+-. © 1991 The American Physical Society.


Exclusive and inclusive semileptonic decays of B mesons to D mesons

Date: 1991-01-01

Creator: R. Fulton

T. Jensen

D. R. Johnson

H. Kagan

R., Kass

F. Morrow

J. Whitmore

P. Wilson

D. Bortoletto

W. Y. Chen

J. Dominick

R. L. McIlwain

D. H. Miller

C. R. Ng

S. F. Schaffner

E. I. Shibata

I. P.J. Shipsey

W. M. Yao

M. Battle

K. Sparks

E. H. Thorndike

C. H. Wang

M. S. Alam

I. J. Kim

W. C. Li

V. Romero

C. R. Sun

P. N. Wang

M. M. Zoeller

M. Goldberg

T. Haupt

Access: Open access

We report new measurements of the branching fractions B. Combining these results with our previous measurement of BD*+l we find that the ratio of semileptonic widths for final states with a vector meson and pseudoscalar meson is (2.6-0.6-0.8+1.1+1.0) and the ratio of charged- to neutral-B-meson lifetimes is (0.89±0.19±0.13)(f00f+-) where (f00f+-) is the ratio of neutral- to charged-B-meson production at the branching fraction, we calculate |Vcb|=0.040±0.006±0.006, where the first error is statistical and the second is systematic and dominated by the uncertainty in the B-meson lifetime. © 1991 The American Physical Society.


Can AFLP genome scans detect small islands of differentiation? The case of shell sculpture variation in the periwinkle Echinolittorina hawaiiensis

Date: 2011-08-01

Creator: Kimberly A. Tice

D. B. Carlon

Access: Open access

Genome scans have identified candidate regions of the genome undergoing selection in a wide variety of organisms, yet have rarely been applied to broadly dispersing marine organisms experiencing divergent selection pressures, where high recombination rates can reduce the extent of linkage disequilibrium (LD) and the ability to detect genomic regions under selection. The broadly dispersing periwinkle Echinolittorina hawaiiensis exhibits a heritable shell sculpture polymorphism that is correlated with environmental variation. To elucidate the genetic basis of phenotypic variation, a genome scan using over 1000 AFLP loci was conducted on smooth and sculptured snails from divergent habitats at four replicate sites. Approximately 5% of loci were identified as outliers with Dfdist, whereas no outliers were identified by BayeScan. Closer examination of the Dfdist outliers supported the conclusion that these loci were false positives. These results highlight the importance of controlling for Type I error using multiple outlier detection approaches, multitest corrections and replicate population comparisons. Assuming shell phenotypes have a genetic basis, our failure to detect outliers suggests that the life history of the target species needs to be considered when designing a genome scan. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.


Schwarzschild-de Sitter spacetimes, McVittie coordinates, and trumpet geometries

Date: 2017-12-15

Creator: Kenneth A. Dennison

Thomas W. Baumgarte

Access: Open access

Trumpet geometries play an important role in numerical simulations of black hole spacetimes, which are usually performed under the assumption of asymptotic flatness. Our Universe is not asymptotically flat, however, which has motivated numerical studies of black holes in asymptotically de Sitter spacetimes. We derive analytical expressions for trumpet geometries in Schwarzschild-de Sitter spacetimes by first generalizing the static maximal trumpet slicing of the Schwarzschild spacetime to static constant mean curvature trumpet slicings of Schwarzschild-de Sitter spacetimes. We then switch to a comoving isotropic radial coordinate which results in a coordinate system analogous to McVittie coordinates. At large distances from the black hole the resulting metric asymptotes to a Friedmann-Lemaître-Robertson-Walker metric with an exponentially-expanding scale factor. While McVittie coordinates have another asymptotically de Sitter end as the radial coordinate goes to zero, so that they generalize the notion of a "wormhole" geometry, our new coordinates approach a horizon-penetrating trumpet geometry in the same limit. Our analytical expressions clarify the role of time-dependence, boundary conditions and coordinate conditions for trumpet slices in a cosmological context, and provide a useful test for black hole simulations in asymptotically de Sitter spacetimes.


Captured segment exchange: A strategy for custom engineering large genomic regions in Drosophila melanogaster

Date: 2013-04-24

Creator: Jack R. Bateman

Michael F. Palopoli

Sarah T. Dale

Jennifer E. Stauffer

Anita L., Shah

Justine E. Johnson

Conor W. Walsh

Hanna Flaten

Christine M. Parsons

Access: Open access

Site-specific recombinases (SSRs) are valuable tools for manipulating genomes. In Drosophila, thousands of transgenic insertions carrying SSR recognition sites have been distributed throughout the genome by several large-scale projects. Here we describe a method with the potential to use these insertions to make custom alterations to the Drosophila genome in vivo. Specifically, by employing recombineering techniques and a dual recombinase-mediated cassette exchange strategy based on the phiC31 integrase and FLP recombinase, we show that a large genomic segment that lies between two SSR recognition-site insertions can be "captured" as a target cassette and exchanged for a sequence that was engineered in bacterial cells. We demonstrate this approach by targeting a 50-kb segment spanning the tsh gene, replacing the existing segment with corresponding recombineered sequences through simple and efficient manipulations. Given the high density of SSR recognition-site insertions in Drosophila, our method affords a straightforward and highly efficient approach to explore gene function in situ for a substantial portion of the Drosophila genome. © 2013 by the Genetics Society of America.


Exploring film language with a digital analysis tool: The case of kinolab

Date: 2021-01-01

Creator: Allison Cooper

Fernando Nascimento

David Francis

Access: Open access

This article presents a case study of Kinolab, a digital platform for the analysis of narrative film language. It describes the need for a scholarly database of clips focusing on film language for cinema and media studies faculty and students, highlighting recent technological and legal advances that have created a favorable environment for this kind of digital humanities work. Discussion of the project is situated within the broader context of contemporary developments in moving image annotation and a discussion of the unique challenges posed by computationally-driven moving image analysis. The article also argues for a universally accepted data model for film language to facilitate the academic crowdsourcing of film clips and the sharing of research and resources across the Semantic Web.


Balancing Survival and Extinction in Nonautonomous Competitive Lotka-Volterra Systems

Date: 1995-06-01

Creator: F. Montes de Oca

M. L. Zeeman

Access: Open access

We generalise and unify some recent results about extinction in nth-order nonautonomous competitive Lotka-Volterra systems. For each r ≤ n, we show that if the coefficients are continuous, bounded by strictly positive constants, and satisfy certain inequalities, then any solution with strictly positive initial values has the property that n - r of its components vanish, whilst the remaining r components asymptotically approach a canonical solution of an r-dimensional restricted system. In other words, r of the species being modeled survive whilst the remaining n - r are driven to extinction. © 1995 Academic Press, Inc.


Simplified insertion of transgenes onto balancer chromosomes via recombinase-mediated cassette exchange

Date: 2012-05-01

Creator: Florence F. Sun

Justine E. Johnson

Martin P. Zeidler

Jack R. Bateman

Access: Open access

Balancer chromosomes are critical tools for Drosophila genetics. Many useful transgenes are inserted onto balancers using a random and inefficient process. Here we describe balancer chromosomes that can be directly targeted with transgenes of interest via recombinase-mediated cassette exchange (RMCE). ©2012 Sun et al.


“Fanny Buitrago: La magia de contar historias”. A Body of One’s Own: Conversations with Caribbean and Latina Writers

Date: 2007-01-01

Creator: Nadia V. Celis Salgado

Fanny Buitrago

Access: Open access