Chemopreventive glucosinolate accumulation in various broccoli and collard tissues: Microfluidic-based targeted transcriptomics for by-product valorization

Floret, leaf, and root tissues were harvested from broccoli and collard cultivars and extracted to determine their glucosinolate and hydrolysis product profiles using high performance liquid chromatography and gas chromotography. Quinone reductase inducing bioactivity, an estimate of anti-cancer chemopreventive potential, of the extracts was measured using a hepa1c1c7 murine cell line. Extracts from root tissues were significantly different from other tissues and contained high levels of gluconasturtiin and glucoerucin. Targeted gene expression analysis on glucosinolate biosynthesis revealed that broccoli root tissue has elevated gene expression of AOP2 and low expression of FMOGS-OX homologs, essentially the opposite of what was observed in broccoli florets, which accumulated high levels of glucoraphanin. Broccoli floret tissue has significantly higher nitrile formation (%) and epithionitrile specifier protein gene expression than other tissues. This study provides basic information of the glucosinolate metabolome and transcriptome for various tissues of Brassica oleracea that maybe utilized as potential byproducts for the nutraceutical market

Liquefaction of H2 molecules upon exterior surfaces of carbon nanotube bundles

We have used molecular dynamics simulations to investigate interaction of H2 molecules on the exterior surfaces of carbon nanotubes (CNTs): single and bundle types. At 80 K and 10 MPa, it is found that charge transfer occurs from a low curvature region to a high curvature region of the deformed CNT bundle, which develops charge polarization only on the deformed structure. The long-range electrostatic interactions of polarized charges on the deformed CNT bundle with hydrogen molecules are observed to induce a high local-ordering of H2 gas that results in hydrogen liquefaction. Our predicted heat of hydrogen liquefaction on the CNT bundle is 97.6 kcal kg^-1. On the other hand, hydrogen liquefaction is not observed in the CNT of a single type. This is because charge polarization is not developed on the single CNT as it is symmetrically deformed under the same pressure. Consequently, the hydrogen storage capacity on the CNT bundle is much higher due to liquefaction than that on the single CNT. Additionally, our results indicate that it would also be possible to liquefy H2 gas on a more strongly polarized CNT bundle at temperatures higher than 80 K

The theoretical study on interaction of hydrogen with single-walled boron nitride nanotubes. I. The reactive force field ReaxFFHBN development

We present a new reactive force field ReaxFFHBN derived to accurately model large molecular and condensed phase systems of H, B, and N atoms. ReaxFFHBN has been tested against quantum calculation data for B–H, B–B, and B–N bond dissociations and for H–B–H, B–N–B, and N–B–N bond angle strain energies of various molecular clusters. The accuracy of the developed ReaxFFHBN for B–N–H systems is also tested for (i) H–B and H–B bond energies as a function of out of plane in H–B(NH2)3 and H–N(BH2)3, respectively, (ii) the reaction energy for the B3N3H6+H2-->B3N3H8, and (iii) crystal properties such as lattice parameters and equations of states for the hexagonal type (h-BN) with a graphite structure and for the cubic type (c-BN) with a zinc-blende structure. For all these systems, ReaxFFHBN gives reliable results consistent with those from quantum calculations as it describes well bond breaking and formation in chemical processes and physical properties. Consequently, the molecular-dynamics simulation based on ReaxFFHBN is expected to give a good description of large systems (>2000 atoms even on the one-CPU machine) with hydrogen, boron, and nitrogen atoms

Theoretical study on interaction of hydrogen with single-walled boron nitride nanotubes. II. Collision, storage, and adsorption

Collision and adsorption of hydrogen with high incident kinetic energies on a single-walled boron nitride (BN) nanotube have been investigated. Molecular-dynamics (MD) simulations indicate that at incident energies below 14 eV hydrogen bounces off the BN nanotube wall. On the other hand, at incident energies between 14 and 22 eV each hydrogen molecule is dissociated at the exterior wall to form two hydrogen atoms, but only one of them goes through the wall. However, at the incident energies between 23 and 26 eV all of the hydrogen atoms dissociated at the exterior wall are found to be capable of going inside the nanotube and then to recombine to form hydrogen molecules inside the nanotube. Consequently, it is determined that hydrogen should have the incident energy >22 eV to go inside the nanotube. On the other hand, we find that the collisions using the incident energies >26 eV could result in damaging the nanotube structures. In addition our MD simulations find that hydrogen atoms dissociated at the wall cannot bind to either boron or nitrogen atoms in the interior wall of the nanotube

Metal work-function-dependent barrier height of Ni contacts with metal-embedded nanoparticles to 4H-SiC

Metal, typically gold [Au], nanoparticles [NPs] embedded in a capping metal contact layer onto silicon carbide [SiC] are considered to have practical applications in changing the barrier height of the original contacts. Here, we demonstrate the use of silver [Ag] NPs to effectively lower the barrier height of the electrical contacts to 4H-SiC. It has been shown that the barrier height of the fabricated SiC diode structures (Ni with embedded Ag-NPs) has significantly reduced by 0.11 eV and 0.18 eV with respect to the samples with Au-NPs and the reference samples, respectively. The experimental results have also been compared with both an analytic model based on Tung's theory and physics-based two-dimensional numerical simulations

Computer use at work is associated with self-reported depressive and anxiety disorder

Adjusted OR* of DAD considering the combined effect of computer use and occupational group, education, and job status. (DOC 61 kb

Bacillus subtilis JW1 enhances plant growth and nutrient uptake of Chinese cabbage through gibberellins secretion

In the present study, we have isolated rhizospheric bacteria JW1 from rice paddy in Andong, South Korea. The culture filtrate (CF) analysis of JW1 showed higher contents of gibberellins GA1, GA4, GA7, organic acids, fatty acids and tricalcium phosphates. The 16S rDNA gene sequencing and phylogentic analysis revealed that thestrain JW1 has a 99% homology with Bacillus subtilis sequences from BLAST search.The growth promotion capability of the strain JW1 was initially assessed on Waito-C and Whayoung-beyo rice cultivars, which improved the growth attributes of the rice cultivars. Similarly, a significant increase in plant height, biomass, chlorophyll contents and nutrient uptake have been noticed, when the Chinese cabbage was treated with JW1 strain. From the results, it is concluded that the integrative use of B. subtilis JW1 can promote plant growthby secreting bioactive compounds. Therefore, B. subtilis JW1 may be utilized as an eco-friendly bio-fertilizer in the agricultural fields after successful field trials

The application of diniconazole and prohydrojasmon as plant growth regulators to induce growth and tuberization of potato

The potato is a major vegetable crop around the world, and tuberous hypertrophy is a highly complex developmental process effected by various factors that play central role in potato growth. Tuber growth under hypertrophic conditions is regulated by variations in carbohydrates and endogenous phytohormones. In the present study, we aimed to establish the basis for the enlargement of potato tubers, including changes in the chemical content of factors related to tuber formation and hypertrophy based on phytohormonal regulation, plants height and tuber biomass and other selected attributes. Our results reveal that the application of plant growth regulators such as diniconazole (Din) and prohydrojasmon (PDJ) significantly impact on potato plants growth and yield, including that of tubers. Plants treated with Din and PDJ effectively showed stunted growth and re-duced development but enhance the tuber formation and its weight. Plants treated with Din and PDJ significantly reduced the GAs and ABA accumulation and increase the sucrose level and cause significant increase in tuber development. In conclusion, a higher gibberellin content in potatoes may inhibit tuberization. Diniconazole and PDJ treatment reduced gibberellin accumulation, which in turn regu-lated abscisic acid content, demonstrating that the abscisic acid content mostly increased as gibberellin content decreased, and thereby promoting tuberization

Anti-reflective nano- and micro-structures on 4H-SiC for photodiodes

In this study, nano-scale honeycomb-shaped structures with anti-reflection properties were successfully formed on SiC. The surface of 4H-SiC wafer after a conventional photolithography process was etched by inductively coupled plasma. We demonstrate that the reflection characteristic of the fabricated photodiodes has significantly reduced by 55% compared with the reference devices. As a result, the optical response Iillumination/Idark of the 4H-SiC photodiodes were enhanced up to 178%, which can be ascribed primarily to the improved light trapping in the proposed nano-scale texturing