Effect of Light Quality and Quantity on the Accumulation of Flavonoid in Plant Species

Light effects including its intensity, wavelength, and duration are important environmental factors that affects flavonoid accumulation. Ultraviolet (UV) light can induce flavonoid biosynthesis. Under normal condition, flavonoids are produced in response to stress, and they function as UV filters. In this paper, we review how light quality and quantity affect the accumulation of flavonoid in plant species. High light intensity can influence flavonoid accumulation, but in heliophytes, the opposite is true. Some medicinal plants require shady environment for flavonoid accumulation. In monocots, the flavonoid is situated in both epidermis and mesophyll while in dicot, it is found only in the epidermis. This review leads to a conclusion that high variation in flavonoids accumulation in response to light can occur within and between plant species

Spatial variation of subduction zone fluids during progressive subduction: Insights from Serpentinite Mud Volcanoes

Geological processes at subduction zones control seismicity, plutonism and volcanism, and geochemical cycling between the oceans, crust, and mantle. The down-going plate experiences metamorphism, and the associated dehydration and fluid flow alters the physical properties of the plate interface and mantle wedge, as well as controlling the composition of material descending into the mantle. Any direct study of slab evolution during subduction is inhibited by the prohibitive depths at which these processes occur. To examine these processes we use serpentinite mud volcanoes in the Mariana forearc, that permit sampling of serpentinite materials and their pore waters that ascend from the subduction channel. We present new pore water chemical data from the summit and flanks of three serpentinite mud volcanoes that were drilled during International Ocean Discovery Program Expedition 366 which are reflective of reactions within the crust and mantle during the early, shallow (<20 km) stages of subduction. We show, via thermodynamic modelling, that our new data on the evolution of pore water chemical compositions reflect mineralogical characteristics of a predominately basaltic source from the downgoing Pacific Plate. However, a component from sedimentary sources is likely, especially for those mud volcanoes near the trench. Other potential slab-derived constituents, such as lithospheric serpentinite, carbonate-rich sediments, or seamount basalts with an intraplate geochemical character, are not required to explain our results. Our results indicate that with progressive subduction the lawsonite-epidote mineral transformation boundary at ∼250 °C may help drive slab carbonate destabilisation, despite its apparent thermodynamic stability at such temperatures and projected pressures (∼300 °C and ∼0.6 GPa). New dissolved gas data also point to primary thermodynamic controls over methane/ethane production within the subduction channel as depths-to-slab increase. Our findings provide direct evidence for the progressive mineralogical and chemical evolution of a subducting oceanic plate, which liberates a progressively evolving fluid phase into the subduction channel

Requirement of RIZ1 for cancer prevention by methyl-balanced diet

The typical Western diet is not balanced in methyl nutrients that regulate the level of the methyl donor S-adenosylmethionine (SAM) and its derivative metabolite S-adenosylhomocysteine (SAH), which in turn may control the activity of certain methyltransferases. Feeding rodents with amino acid defined and methyl-imbalanced diet decreases hepatic SAM and causes liver cancers. RIZ1 (PRDM2 or KMT8) is a tumor suppressor and functions in transcriptional repression by methylating histone H3 lysine 9. Here we show that a methyl-balanced diet conferred additional survival benefits compared to a tumor-inducing methyl-imbalanced diet only in mice with wild type RIZ1 but not in mice deficient in RIZ1. While absence of RIZ1 was tumorigenic in mice fed the balanced diet, its presence did not prevent tumor formation in mice fed the imbalanced diet. Unlike most of its related enzymes, RIZ1 was upregulated by methyl-balanced diet. Methyl-balanced diet did not fully repress oncogenes such as c-Jun in the absence of RIZ1. The data identify RIZ1 as a critical target of methyl-balanced diet in cancer prevention. The molecular understanding of dietary carcinogenesis may help people make informed choices on diet, which may greatly reduce the incidence of cancer

How unique is the Asymptotic Normalisation Coefficient (ANC) method?

The asymptotic normalisation coefficients (ANC) for the vertex $^{10}$B $\to$ $^9$Be + p is deduced from a set of different proton transfer reactions at different energies. This set should ensure the peripheral character of the reaction and availability of data for the elastic channels. The problems associated with the characteristics of the data and the analysis are discussed. For a subgroup of the set of available data, the uniqueness property of the extracted ANC is fulfilled. However, more measurements are needed before a definite conclusion can be drawn.Comment: 19 pages, 11 figures, to be published in Phys Rev

Quantum Conductance in Silver Nanowires: correlation between atomic structure and transport properties

We have analyzed the atomic arrangements and quantum conductance of silver nanowires generated by mechanical elongation. The surface properties of Ag induce unexpected structural properties, as for example, predominance of high aspect ratio rod-like wires. The structural behavior was used to understand the Ag quantum conductance data and the proposed correlation was confirmed by means of theoretical calculations. These results emphasize that the conductance of metal point contacts is determined by the preferred atomic structures and, that atomistic descriptions are essential to interpret the quantum transport behavior of metal nanostructures.Comment: 4 pages, 4 figure

Hard probes in heavy ion collisions at the LHC: PDFs, shadowing and pApA collisions

This manuscript is the outcome of the subgroup ``PDFs, shadowing and $pA$ collisions'' from the CERN workshop ``Hard Probes in Heavy Ion Collisions at the LHC''. In addition to the experimental parameters for $pA$ collisions at the LHC, the issues discussed are factorization in nuclear collisions, nuclear parton distributions (nPDFs), hard probes as the benchmark tests of factorization in $pA$ collisions at the LHC, and semi-hard probes as observables with potentially large nuclear effects. Also, novel QCD phenomena in $pA$ collisions at the LHC are considered. The importance of the $pA$ program at the LHC is emphasized.Comment: The writeup of the working group "PDFs, shadowing and $pA$ collisions" for the CERN Yellow Report on Hard Probes in Heavy Ion Collisions at the LHC, 121 pages. Subgroup convenors: K.J. Eskola, J.w. Qiu (theory) and W. Geist (experiment). Editor: K.J. Eskol