3,525 research outputs found
Construction of Infrared Finite Observables in N=4 Super Yang-Mills Theory
In this paper we give all the details of the calculation that we presented in
our previous paper ArXiv:0908.0387 where the infrared structure of the MHV
gluon amplitudes in the planar limit for super Yang-Mills theory
was considered in the next-to-leading order of perturbation theory. Explicit
cancellation of the infrared divergencies in properly defined inclusive
cross-sections is demonstrated first in a toy model example of "conformal QED"
and then in the real SYM theory. We give the full-length details
both for the calculation of the real emission and for the diagrams with
splitting in initial and final states. The finite parts for some inclusive
differential cross-sections are presented in an analytical form. In general,
contrary to the virtual corrections, they do not reveal any simple structure.
An example of the finite part containing just the log functions is presented.
The dependence of inclusive cross-section on the external scale related to the
definition of asymptotic states is discussed.Comment: 49 pages, LATEX, 6 eps figures; Minor changes, Refs adde
Diagnosis and treatment of hereditary angioedema with normal C1 inhibitor
Until recently it was assumed that hereditary angioedema is a disease that results exclusively from a genetic deficiency of the C1 inhibitor. In 2000, families with hereditary angioedema, normal C1 inhibitor activity and protein in plasma were described. Since then numerous patients and families with that condition have been reported. Most of the patients by far were women. In many of the affected women, oral contraceptives, hormone replacement therapy containing estrogens, and pregnancies triggered the clinical symptoms. Recently, in some families mutations in the coagulation factor XII (Hageman factor) gene were detected in the affected persons
UNEQUAL JUSTICE UNDER LAW: AN ANALYSIS OF INDIGENTS IN THE CRIMINAL JUSTICE SYSTEM—THE INDIANA EXPERIENCE
UNEQUAL JUSTICE UNDER LAW: AN ANALYSIS OF INDIGENTS IN THE CRIMINAL JUSTICE SYSTEM—THE INDIANA EXPERIENCE
A summary index of feeding practices is positively associated with height-for-age, but only marginally with linear growth, in rural Senegalese infants and toddlers
Several studies have shown an association between an infant and young child feeding index (ICH) and height-for-age Z-score (HAZ) in Latin America and Africa. A previous study was unable to reproduce these findings in 500 rural Senegalese 12-42-mo-old children. The relationship of ICFI, dietary diversity index (DDI), food variety index (FVI), meal frequency index (MFI), and breastfeeding (BF) to HAZ and growth in height/length over 6 mo was studied in 1060 6-36-mo-old Senegalese children during 2 visits. List-based food frequencies were recalled for the past 24 h, and height/length and weight measurements were taken. Indicators were transformed into tertiles in age-specific subgroups. DDI, FVI, MFI, and ICFI were poorly concordant across visits at all ages (weighted kappa: 0.02-0.25). In cross-sectional analyses that pooled children from the 2 visits, HAZ was positively associated with DDI and FVI at 6-12, 12-18, and 18-24 mo and with ICFI at 6-12 and 18-24 mo (P < 0.001 and P < 0.05, respectively) but was negatively associated with BF at 12-18, 18-24, and 24-30 mo. The length increment between visits was positively associated with MFI and ICFI, measured during the first visit in 18-24-mo-olds (P < 0.001 and P < 0.05, respectively) but not with DDI, FVI, or BF at any age. In conclusion, ICFI, DDI, and FVI were associated with HAZ, particularly during infancy, whereas no indicator was associated with linear growth in this age group. Therefore, the strong association between HAZ and ICFI during infancy may be partly due to maternal adaptation to infant clues, i.e., greater appetite for and interest in non-breast-milk foods among taller infants. J. Nutr. 142: 1116-1122, 2012
Energy efficiency trade-offs drive nucleotide usage in transcribed regions
Efficient nutrient usage is a trait under universal selection. A substantial part of cellular resources is spent on making nucleotides. We thus expect preferential use of cheaper nucleotides especially in transcribed sequences, which are often amplified thousand-fold compared with genomic sequences. To test this hypothesis, we derive a mutation-selection-drift equilibrium model for nucleotide skews (strand-specific usage of 'A' versus 'T' and 'G' versus 'C'), which explains nucleotide skews across 1,550 prokaryotic genomes as a consequence of selection on efficient resource usage. Transcription-related selection generally favours the cheaper nucleotides 'U' and 'C' at synonymous sites. However, the information encoded in mRNA is further amplified through translation. Due to unexpected trade-offs in the codon table, cheaper nucleotides encode on average energetically more expensive amino acids. These trade-offs apply to both strand-specific nucleotide usage and GC content, causing a universal bias towards the more expensive nucleotides 'A' and 'G' at non-synonymous coding sites
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