212 research outputs found
Interpretations of the ATLAS Diboson Anomaly
Recently, the ATLAS Collaboration recorded an interesting anomaly in diboson
production with excesses at the diboson invariant mass around 2 TeV in boosted
jets of all the , , and channels. We offer a theoretical
interpretation of the anomaly using a phenomenological right-handed model with
extra and bosons. Constraints from narrow total decay widths, dijet
cross sections, and production are taken into account. We also
comment on a few other possibilities.Comment: v4: match the published version; v3: 18 pages, 6 figures, change to
leptophobic Z' model to take into account the EW constraints, and some
updates to the analysis and text; v2: 17 pages, 7 figures; a new section and
a new figure are added; correct the statement about the WH; references are
also adde
Chemical composition and physical characteristics of water caltrop during growth
[[abstract]]BACKGROUND: The aim of this study was to monitor the chemical composition and physical and morphological characteristics of two varieties of water caltrop during growth in order to determine the optimal harvesting time.
RESULTS: The dry matter, starch and amylose contents and alpha-amylase activity of fruits of both water caltrop varieties increased during the growth period. Mature fruits contained 142-156 g starch kg(-1) fresh sample and provided 684-697 kcal total energy kg(-1) fresh sample. Dry matter content and bulk density increased significantly from 67 to 207 g kg(-1) and from 0.57 to 1.58 g ml(-1) respectively as growth progressed. Morphological analysis showed that the size and number of starch granules increased as growth progressed. Moreover, both varieties contained substantial amounts of essential amino acids, most of which appeared to be superior to the FAO/WHO reference pattern.
CONCLUSION: According to the chemical composition and physical characteristics of water caltrop determined in this study, the optimal harvesting time is 42 days after fruit development. (C) 2009 Society of Chemical Industr
Distribution of Phenolic Compounds and Antioxidative Activities of Rice Kernel and Their Relationships with Agronomic Practice
The phenolic and antioxidant activity of ethanolic extract of two Japonica rice cultivars, Taikeng no. 16 (medium and slender grain) and Kaohsiung no. 139 (short and round grain), grown under organic and conventional farming were examined. Analyses shows that Kaohsiung no. 139 contains the highest amount of secondary metabolites and continuous farming can increase its production. Results also suggest that phenolic content under different agronomic practices, has not shown significant differences but organically grown rice has proven to be better in higher accumulation of other secondary metabolites (2,2-diphenyl-1-picrylhydrazyl (DPPH), flavonoid content, and ferrous chelating capacity). In nutshell, genetic traits and environment have significant effect on phenolic compounds and the least variation reported under agronomic practices
DNA Binding and Degradation by the HNH Protein ColE7
The bacterial toxin ColE7 bears an HNH motif which has been identified in hundreds of prokaryotic and eukaryotic endonucleases, involved in DNA homing, restriction, repair, or chromosome degradation. The crystal structure of the nuclease domain of ColE7 in complex with a duplex DNA has been determined at 2.5 Å resolution. The HNH motif is bound at the minor groove primarily to DNA phosphate groups at and beyond the 3′ side of the scissile phosphate, with little interaction with ribose groups and bases. This result provides a structural basis for sugar- and sequence-independent DNA recognition and the inhibition mechanism by inhibitor Im7, which blocks the substrate binding site but not the active site. Structural comparison shows that two families of endonucleases bind and bend DNA in a similar way to that of the HNH ColE7, indicating that endonucleases containing a “ββα-metal” fold of active site possess a universal mode for protein-DNA interactions
Gamma-ray Constraints on Effective Interactions of the Dark Matter
Using an effective interaction approach to describe the interactions between
the dark matter particle and the light degrees of freedom of the standard
model, we calculate the gamma-ray flux due to the annihilation of the dark
matter into quarks, followed by fragmentation into neutral pions which
subsequently decay into photons. By comparison to the mid-latitude data
released from the Fermi-LAT experiment, we obtain useful constraints on the
size of the effective interactions and they are found to be comparable to those
deduced from collider, gamma-ray line and anti-matter search experiments.
However, the two operators induced by scalar and vector exchange among
fermionic dark matter and light quarks that contribute to spin-independent
cross sections are constrained more stringently by the recent XENON100 data.Comment: 22 pages, 4 figures; title fixed and a couple of references adde
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