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111.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bacchetta N Bailey MW Bamberger A Barnett BA Barbaro-Galtieri A Barnes VE Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Castro A Cervelli F Chadwick K 《Physical review letters》1992,68(10):1458-1462
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114.
Andreas Basse-O’Connor Mikkel Slot Nielsen Jan Pedersen Victor Rohde 《Stochastic Processes and their Applications》2019,129(10):4119-4143
In this study we show how to represent a continuous time autoregressive moving average (CARMA) as a higher order stochastic delay differential equation, which may be thought of as a CAR() representation. Furthermore, we show how the CAR() representation gives rise to a prediction formula for CARMA processes. To be used in the above mentioned results we develop a general theory for multivariate stochastic delay differential equations, which will be of independent interest, and which will have particular focus on existence, uniqueness and representations. 相似文献
115.
Addition reactions of allyl stannanes to an indolo[2′,3′:3,4]pyrido[1,2‐b]isoquinoline imminium salt
Paul C. Unangst Larry D. Bratton David T. Connor Bruce D. Roth J. Ronald Rubin Bharat K. Trivedi 《Journal of heterocyclic chemistry》2000,37(5):1081-1087
The addition of organometallic reagents to the 13b‐position of the indolo[2′,3′:3,4]pyrido[1,2‐b]isoquinoline imminium salt 4 is described. Reaction of 4 with tetraallyl tin in 2‐methoxyethanol gave the allyl adduct 7 in moderate yield. Further elaboration of 7 yielded the pentacyclic benzylidene alcohols 13 and 14 . Structure elucidation of the compounds prepared was achieved by a combination of 1H nmr spec troscopy and X‐ray crystallography. 相似文献
116.
The challenge of annotating protein sequences: The tale of eight domains of unknown function in Pfam
Nalin C.W. Goonesekere Krysten Shipely Kevin O’Connor 《Computational Biology and Chemistry》2010,34(3):210-214
The Pfam database is an important tool in genome annotation, since it provides a collection of curated protein families. However, a subset of these families, known as domains of unknown function (DUFs), remains poorly characterized. We have related sequences from DUF404, DUF407, DUF482, DUF608, DUF810, DUF853, DUF976 and DUF1111 to homologs in PDB, within the midnight zone (9–20%) of sequence identity. These relationships were extended to provide functional annotation by sequence analysis and model building. Also described are examples of residue plasticity within enzyme active sites, and change of function within homologous sequences of a DUF. 相似文献
117.
O'Connor PB Lin C Cournoyer JJ Pittman JL Belyayev M Budnik BA 《Journal of the American Society for Mass Spectrometry》2006,17(4):576-585
To explore the mechanism of electron capture dissociation (ECD) of linear peptides, a set of 16-mer peptides were synthesized with deuterium labeled on the alpha-carbon position of four glycines. The ECD spectra of these peptides showed that such peptides exhibit a preference for the radical to migrate to the alpha-carbon position on glycine via hydrogen (or deuterium) abstraction before the final cleavage and generation of the detected product ions. The data show c-type fragment ions, ions corresponding to the radical cation of the c-type fragments, c*, and they also show c*-1 peaks in the deuterated peptides only. The presence of the c*-1 peaks is best explained by radical-mediated scrambling of the deuterium atoms in the long-lived, metastable, radical intermediate complex formed by initial electron capture, followed by dissociation of the complex. These data suggest the presence of at least two mechanisms, one slow, one fast. The abundance of H* and -CO losses from the precursor ion changed upon deuterium labeling indicating the presence of a kinetic isotope effect, which suggests that the values reported here represent an underestimation of radical migration and H/D scrambling in the observed fragments. 相似文献
118.
Jennifer Melia Eric Connor Stephen Rush Stefan Breunig Christof Mehler Wilhelm Risse 《Macromolecular Symposia》1995,89(1):433-442
Cationic Pd(II) -complexes with weakly coordinating ligands were used for the olefin addition polymerization of strained polycyclic olefins. The cyclic structure of the monomers remained intact during the reaction which contrasts with products obtained from the olefin metathesis polymerization. The Pd(II) -catalyzed polymerizations showed the features of a “living” polymerization, when norbornene and selected exo-substituted norbornene derivatives were used as the monomers. Endo- and exo-dicyclopentadiene, exo-1,2-dihydrodicyclopentadiene, endo, exo-1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene and endo, exo-1,4,5,8-dimethano-1,4,4,a,5,8,8a-hexahydronaphthalene were converted into the corresponding rigid polymers. The exo-substituted monomers were found to polymerize at a higher rate than the corresponding or similar endo-substituted monomers. The polymerization of norbornadiene and the subsequent thermal elimination of cyclopentadiene resulted in the formation of polyacetylene. 相似文献
119.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review letters》1990,64(2):147-151
120.
Photoelectron spectroscopy and X-ray absorption spectroscopy (XAS) measurements have been performed on HfSixOy and HfSixOyNz dielectric layers, which are potential candidates as high-k transistor gate dielectrics. The hafnium silicate layers, 3-4 nm thick, were formed by codepositing HfO2 and SiO2 (50%:50%) by MOCVD at 485 °C on a silicon substrate following an IMEC clean. Annealing the HfSixOy layer in a nitrogen atmosphere at 1000 °C resulted in an increase in the Si4+ chemical shift from 3.5 to 3.9 eV with respect to the Si0 peak. Annealing the hafnium silicate layer in a NH3 atmosphere at 800 °C resulted in the incorporation of 10% nitrogen and the decrease in the chemical shift between the Si4+ and the Si0 to 3.3 eV. The results suggest that the inclusion of nitrogen in the silicate layer restricts the tendency of the HfO2 and the SiO2 to segregate into separate phases during the annealing step. Synchrotron radiation valence band photoemission studies determined that the valence band offsets were of the order of 3 eV. X-ray absorption measurements show that the band gap of these layers is 4.6 eV and that the magnitude of the conduction band offset is as little as 0.5 eV. 相似文献