Next-to-leading order numerical calculations in Coulomb gauge

Calculations of observables in quantum chromodynamics can be performed using a method in which all of the integrations, including integrations over virtual loop momenta, are performed numerically. We use the flexibility inherent in this method in order to perform next-to-leading order calculations for event shape variables in electron-positron annihilation in Coulomb gauge. The use of Coulomb gauge provides the potential to go beyond a purely order alpha_s^2 calculation by including, for instance, renormalon or parton showering effects. We expect that the approximations needed to include such effects at all orders in alpha_s will be simplest in a gauge in which unphysically polarized gluons do not propagate over long distances.Comment: 36 pages with 7 figure

Ligand electronic fine-tuning and its repercussion on the photocatalytic activity and mechanistic pathways of the copper-photocatalysed aza-Henry reaction

A family of six structurally related heteroleptic copper(i) complexes of the form of [Cu(N^N)(P^P)]+ bearing a 2,9-dimethyl-1,10-phenanthroline diimine (N^N) ligand and a series of electronically tunable xantphos (P^P) ligands have been synthesized and their optoelectronic properties characterized. The reactivity of these complexes in the copper-photocatalyzed aza-Henry reaction of N-phenyltetrahydroisoquinoline was evaluated, while the related excited state kinetics were comprehensively studied. By subtlety changing the electron-donating properties of the P^P ligands with negligible structural differences, we could tailor the photoredox properties and relate them to the reactivity. Moreover, depending on the exited-state redox potential of the catalysts, the preferred mechanism can shift between reductive quenching, energy transfer and oxidative quenching pathways. A combined study of the structural modulation of copper(i) photocatalysts, optoelectronic properties and photocatalytic reactivity resulted in a clearer understanding of both the rational design of the photocatalyst and the complexity of competing photoinduced electron and energy transfer mechanisms. © The Royal Society of Chemistry

MicroRNA profiling in oesophageal adenocarcinoma cell lines and patient serum samples reveals a role for mir-451a in radiation resistance

Many patients with Oesophageal Adenocarcinoma (OAC) do not benefit from chemoradiotherapy treatment due to therapy resistance. To better understand the mechanisms involved in resistance and to find potential biomarkers, we investigated the association of microRNAs, which regulate gene expression, with the response to individual treatments, foc

Fragmentation processes of ionized 5-fluorouracil in the gas phase and within clusters

We have measured mass spectra for positive ions produced from neutral 5-fluorouracil by electron impact at energies from 0 to 100 eV. Fragment ion appearance energies of this (radio-)chemotherapy agent have been determined for the first time and we have identified several new fragment ions of low abundance. The main fragmentations are similar to uracil, involving HNCO loss and subsequent HCN loss, CO loss, or FCCO loss. The features adjacent to these prominent peaks in the mass spectra are attributed to tautomerization preceding the fragmentation and/or the loss of one or two additional hydrogen atoms. A few fragmentions are distinct for 5-fluorouracil compared to uracil, most notably the production of the reactive moiety CF+. Finally, multiphoton ionization mass spectra are compared for 5-fluorouracil from a laser thermal desorption source and from a supersonic expansion source. The detection of a new fragment ion at 114 u in the supersonic expansion experiments provides the first evidence for a clustering effect on the radiation response of 5-fluorouracil. By analogy with previous experiments and calculations on protonated uracil, this is assigned to NH3 loss from protonated 5-fluorouracil

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

Heritabilities and genetic correlations of ultrasound-measured ribeye area with other performance traits in Brangus cattle

Heritabilities and genetic correlations for ultrasound-measured ribeye area and fat thickness, as well as growth traits and scrotal circumference, were determined using performance records of 1613 Brangus calves born from 1987 to 1990. Moderate heritabilities of .39 for weaning and .40 for yearling ultrasound- measured ribeye area indicate that selection to change these traits should be effective. The positive, and generally large, genetic correlations between ultrasound-measured ribeye areas and growth traits indicate that genetic change of these traits can be made in tandem. The low heritability (.14) of fat thickness, the small amount of fat, and the lack of variation would make it very difficult to change the genetic ability of animals to deposit fat

Baryonic B Meson Decays

Recent results of the baryonic B decays from the two b-factories, BABAR and Belle, are presented. These include studies of charmonium decays from B + → p p ¯ K + and B + → Λ Λ ¯ K + ; observations of B + → J / ψ Λ ¯ p , B + → Λ c + Λ ¯ c − K and B + → Ξ ¯ c 0 Λ c + and study of of inclusive B decays to Λ c

Ultrasound-measured ribeye area EPD for Brangus cattle

Ultrasound-measured ribeye area (REA) expected progeny differences (EPD) were calculated for 2974 Brangus cattle. Carcass data were collected from 168 steer progeny sired by eight bulls with ultrasound-measured ribeye area EPDs. A heritability estimate of .40 for ultrasound-measured REA and a 2.82 sq. in. range in genetic differences in ultrasound- measured REAs in this population indicate considerable opportunity to make genetic change in this trait. The regression of progeny average carcass REA on the sire's ultrasound measured ribeye area EPD indicated that for each square inch change in the EPD, the carcass REA of their progeny changed by .69 sq. in. The ultrasound-measured ribeye area EPD of young breeding stock appears to be a reasonably good predictor of their progeny's carcass ribeye area