Showing 1481 - 1490 of 2039 Items
Date: 1994-01-01
Creator: J. Dominick
S. Sanghera
V. Shelkov
T. Skwarnicki
R., Stroynowski
I. Volobouev
P. Zadorozhny
M. Artuso
D. He
M. Goldberg
N. Horwitz
R. Kennett
G. C. Moneti
F. Muheim
Y. Mukhin
S. Playfer
Y. Rozen
S. Stone
M. Thulasidas
G. Vasseur
G. Zhu
J. Bartelt
S. E. Csorna
Z. Egyed
V. Jain
P. Sheldon
D. S. Akerib
B. Barish
M. Chadha
S. Chan
D. F. Cowen
Access: Open access
- The CLEO II detector is used to search for the production of χc2 states in two-photon interactions. We use the signature χc2→γJ/ ψ→γl+l- with l=e,μ. Using 1.49 fb-1 of data taken with beam energies near 5.29 GeV, the two-photon width of the χc2 is determined to be Γ(χc2→γγ)=1.08±0.30(stat)±0.26(syst) keV, in agreement with predictions from perturbative QCD. © 1994 The American Physical Society.
Date: 2016-09-21
Creator: Cathy M. Trudinger
Paul J. Fraser
David M. Etheridge
William T. Sturges
Martin K., Vollmer
Matt Rigby
Patricia Martinerie
Jens Mühle
David R. Worton
Paul B. Krummel
L. Paul Steele
Benjamin R. Miller
Johannes Laube
Francis S. Mani
Peter J. Rayner
Christina M. Harth
Emmanuel Witrant
Thomas Blunier
Jakob Schwander
Simon O'Doherty
Mark Battle
Access: Open access
- Perfluorocarbons (PFCs) are very potent and long-lived greenhouse gases in the atmosphere, released predominantly during aluminium production and semiconductor manufacture. They have been targeted for emission controls under the United Nations Framework Convention on Climate Change. Here we present the first continuous records of the atmospheric abundance of CF4 (PFC-14), C2F6 (PFC-116) and C3F8 (PFC-218) from 1800 to 2014. The records are derived from high-precision measurements of PFCs in air extracted from polar firn or ice at six sites (DE08, DE08-2, DSSW20K, EDML, NEEM and South Pole) and air archive tanks and atmospheric air sampled from both hemispheres. We take account of the age characteristics of the firn and ice core air samples and demonstrate excellent consistency between the ice core, firn and atmospheric measurements. We present an inversion for global emissions from 1900 to 2014. We also formulate the inversion to directly infer emission factors for PFC emissions due to aluminium production prior to the 1980s. We show that 19th century atmospheric levels, before significant anthropogenic influence, were stable at 34.1 ± 0.3 ppt for CF4 and below detection limits of 0.002 and 0.01 ppt for C2F6 and C3F8, respectively. We find a significant peak in CF4 and C2F6 emissions around 1940, most likely due to the high demand for aluminium during World War II, for example for construction of aircraft, but these emissions were nevertheless much lower than in recent years. The PFC emission factors for aluminium production in the early 20th century were significantly higher than today but have decreased since then due to improvements and better control of the smelting process. Mitigation efforts have led to decreases in emissions from peaks in 1980 (CF4) or early-to-mid-2000s (C2F6 and C3F8) despite the continued increase in global aluminium production; however, these decreases in emissions appear to have recently halted. We see a temporary reduction of around 15 % in CF4 emissions in 2009, presumably associated with the impact of the global financial crisis on aluminium and semiconductor production.
Date: 1994-01-01
Creator: R. Balest
K. Cho
M. Daoudi
W. T. Ford
D. R., Johnson
K. Lingel
M. Lohner
P. Rankin
J. G. Smith
J. P. Alexander
C. Bebek
K. Berkelman
K. Bloom
T. E. Browder
D. G. Cassel
H. A. Cho
D. M. Coffman
P. S. Drell
R. Ehrlich
P. Gaiderev
M. Garcia-Sciveres
B. Geiser
B. Gittelman
S. W. Gray
D. L. Hartill
B. K. Heltsley
C. D. Jones
S. L. Jones
J. Kandaswamy
N. Katayama
P. C. Kim
Access: Open access
- Using the CLEO II detector at the Cornell Electron Storage Ring we have measured the ratio of branching fractions, B(D+K-++)/(D0K-+)=2.350.160.16. Our recent measurement of scrB(D0K-+) then gives scrB(D+K-++)=(9.30.60.8)%. © 1994 The American Physical Society.
Date: 2006-03-01
Creator: Vladimir Douhovnikoff
Caterina Nerney
George K. Roderick
Craig H. Newton
Stephen C., Welter
Access: Open access
- Nine microsatellite loci were isolated from the insect Dolichogenidea homoeosomae (Hymenoptera: Braconidae), an important parasitoid of the sunflower moth Homosoeosoma electellum (Lepidoptera: Pyralidae), and assayed for polymorphism. All nine loci were polymorphic within the five populations tested, with two to 14 alleles per locus. Expected and observed heterozygosities ranged from 0.39 to 0.90 and 0.25 to 0.72 respectively. These are the first microsatellite primers developed for D. homeosomae and will be useful for studies of population dynamics and connectivity. © 2006 Blackwell Publishing Ltd.
Date: 1993-01-01
Creator: J. Bartelt
S. E. Csorna
Z. Egyed
V. Jain
P., Sheldon
D. S. Akerib
B. Barish
M. Chadha
S. Chan
D. F. Cowen
G. Eigen
J. S. Miller
C. O'Grady
J. Urheim
A. J. Weinstein
D. Acosta
M. Athanas
G. Masek
B. Ong
H. Paar
M. Sivertz
A. Bean
J. Gronberg
R. Kutschke
S. Menary
R. J. Morrison
S. Nakanishi
H. N. Nelson
T. K. Nelson
J. D. Richman
A. Ryd
Access: Open access
- We have measured the B0B»0 mixing probability, d, using a sample of 965 000 BB» pairs from (4S) decays. Counting dilepton events, we find d=0.1570.0160.018-0.021+0.028. Using tagged B0 events, we find d=0.1490.0230.0190.010. The first (second) error is statistical (systematic). The third error reflects a 15% uncertainty in the assumption, made in both cases, that charged and neutral B pairs contribute equally to dilepton events. We also obtain a limit on the CP impurity in the Bd0 system, Re(B0)<0.045 at 90% C.L. © 1993 The American Physical Society.
Date: 1992-01-01
Creator: M. Artuso
M. Goldberg
N. Horwitz
R. Kennett
G. C., Moneti
F. Muheim
S. Playfer
Y. Rozen
P. Rubin
S. Stone
M. Thulasidas
W. M. Yao
G. Zhu
A. V. Barnes
J. Bartelt
S. E. Csorna
Z. Egyed
V. Jain
P. Sheldon
D. S. Akerib
B. Barish
M. Chadha
D. F. Cowen
G. Eigen
J. S. Miller
J. Urheim
A. J. Weinstein
D. Acosta
G. Masek
B. Ong
H. Paar
Access: Open access
- The decay 0 has been observed for the first time using the CLEO-II detector at the Cornell Electron Storage Ring. The measured branching ratio (0.170.020.02)%, agrees with the CVC (conserved vector current) prediction based on e+e-+- data. Upper limits on the branching ratios for other decays to final states including mesons are improved by an order of magnitude compared to previous measurements. © 1992 The American Physical Society.
Date: 2018-03-01
Creator: Andrew E. Christie
Alexandra Miller
Rebecca Fernandez
Evyn S. Dickinson
Audrey, Jordan
Jessica Kohn
Mina C. Youn
Patsy S. Dickinson
Access: Open access
- The crustacean stomatogastric nervous system (STNS) is a well-known model for investigating neuropeptidergic control of rhythmic behavior. Among the peptides known to modulate the STNS are the C-type allatostatins (AST-Cs). In the lobster, Homarus americanus, three AST-Cs are known. Two of these, pQIRYHQCYFNPISCF (AST-C I) and GNGDGRLYWRCYFNAVSCF (AST-C III), have non-amidated C-termini, while the third, SYWKQCAFNAVSCFamide (AST-C II), is C-terminally amidated. Here, antibodies were generated against one of the non-amidated peptides (AST-C I) and against the amidated isoform (AST-C II). Specificity tests show that the AST-C I antibody cross-reacts with both AST-C I and AST-C III, but not AST-C II; the AST-C II antibody does not cross-react with either non-amidated peptide. Wholemount immunohistochemistry shows that both subclasses (non-amidated and amidated) of AST-C are distributed throughout the lobster STNS. Specifically, the antibody that cross-reacts with the two non-amidated peptides labels neuropil in the CoGs and the stomatogastric ganglion (STG), axons in the superior esophageal (son) and stomatogastric (stn) nerves, and ~ 14 somata in each commissural ganglion (CoG). The AST-C II-specific antibody labels neuropil in the CoGs, STG and at the junction of the sons and stn, axons in the sons and stn, ~ 42 somata in each CoG, and two somata in the STG. Double immunolabeling shows that, except for one soma in each CoG, the non-amidated and amidated peptides are present in distinct sets of neuronal profiles. The differential distributions of the two AST-C subclasses suggest that the two peptide groups are likely to serve different modulatory roles in the lobster STNS.
Date: 2012-08-27
Creator: Sonja A. Schwartz
Ann F. Budd
David B. Carlon
Access: Open access
- Background: Even with well-known sampling biases, the fossil record is key to understanding macro-evolutionary patterns. During the Miocene to Pleistocene in the Caribbean Sea, the fossil record of scleractinian corals shows a remarkable period of rapid diversification followed by massive extinction. Here we combine a time-calibrated molecular phylogeny based on three nuclear introns with an updated fossil stratigraphy to examine patterns of radiation and extinction in Caribbean corals within the traditional family Faviidae. Results: Concatenated phylogenetic analysis showed most species of Caribbean faviids were monophyletic, with the exception of two Manicina species. The time-calibrated tree revealed the stem group originated around the closure of the Tethys Sea (17.0 Ma), while the genus Manicina diversified during the Late Miocene (8.20 Ma), when increased sedimentation and productivity may have favored free-living, heterotrophic species. Reef and shallow water specialists, represented by Diploria and Favia, originate at the beginning of the Pliocene (5 - 6 Ma) as the Isthmus of Panama shoaled and regional productivity declined. Conclusions: Later origination of the stem group than predicted from the fossil record corroborates the hypothesis of morphological convergence in Diploria and Favia genera. Our data support the rapid evolution of morphological and life-history traits among faviid corals that can be linked to Mio-Pliocene environmental changes. © 2012 Schwartz et al.; licensee BioMed Central Ltd.
Date: 2016-12-01
Creator: Patsy S. Dickinson
Xuan Qu
Meredith E. Stanhope
Access: Open access
- Central pattern generators are subject to modulation by peptides, allowing for flexibility in patterned output. Current techniques used to characterize peptides include mass spectrometry and transcriptomics. In recent years, hundreds of neuropeptides have been sequenced from crustaceans; mass spectrometry has been used to identify peptides and to determine their levels and locations, setting the stage for comparative studies investigating the physiological roles of peptides. Such studies suggest that there is some evolutionary conservation of function, but also divergence of function even within a species. With current baseline data, it should be possible to begin using comparative approaches to ask fundamental questions about why peptides are encoded the way that they are and how this affects nervous system function.
Date: 1991-01-01
Creator: D. S. Akerib
B. Barish
D. F. Cowen
G. Eigen
R., Stroynowski
J. Urheim
A. J. Weinstein
R. Morrison
D. Schmidt
M. Procario
D. R. Johnson
K. Lingel
P. Rankin
J. G. Smith
J. Alexander
C. Bebek
K. Berkelman
D. Besson
T. E. Browder
D. G. Cassel
E. Cheu
D. M. Coffman
P. S. Drell
R. Ehrlich
R. S. Galik
M. Garcia-Sciveres
B. Geiser
B. Gittelman
S. W. Gray
D. L. Hartill
B. K. Heltsley
Access: Open access
- Using the CLEO II detector at the Cornell Electron Storage Ring, we have determined the inclusive B* cross section above the (4S) resonance in the energy range from 10.61 to 10.70 GeV. We also report a new measurement of the energy of the B*B transition photon of 46.20.30.8 MeV. © 1991 The American Physical Society.