Influence of altitudinal variation on the antioxidant potential of tartar buckwheat of Western Himalaya

In the present work, the effect of altitudinal variations on the total phenol, flavonoid, and antioxidant potential of seeds and hull of Tartar buckwheat collected from 15 different locations of Western Himalaya has been investigated. Methanolic and acetonic extracts of seed and hull powder showed significantly increasing amounts of total polyphenol content, and antioxidant potential with rising altitude. Methanolic extract of seed and hull powder were found to have significantly greater polyphenol, and antioxidant potential as compared to acetonic extract. The methanolic seed extract of Inderdhara (3,133 m) showed the maximum total phenolic content 1,651 μg gallic acid equivalent/50 mg of dry weight. The methanolic seed extract of Inderdhara showed the maximum antioxidant activity (77.29±1.2%) and antiradical activity (55.5±0.5%) also. The results of this study exhibited good correlation with total polyphenol and antioxidant potential in all the samples followed by the increasing tendency towards rising altitude.     

A New Technique for Coating Silicon Carbide Onto Carbon Nanotubes Using a Polycarbosilane Precursor

Multiwalled carbon nanotubes (MWCNTs) have been coated with silicon carbide (SiC) using polycarbosilane as precursor in order to improve their thermo oxidative stability. The polycarbosilane coated MWCNTs were heated to ~1300°C under an inert atmosphere to generate the SiC coating. X-ray diffraction, energy dispersive X-ray analysis and scanning electron microscopy have confirmed the formation of SiC on the MWCNTs. The retention of the tubular structure of the MWCNTs has been confirmed by transmission electron microscopy. Thermogravimetric analysis has been performed to evaluate the thermo oxidative stabilities of coated and virgin MWCNTs. Sonication studies have shown that the mechanical strength of the MWCNTs was increased after coating with SiC.     

Analysis and design of enhanced directivity microstrip antenna at terahertz frequency by using electromagnetic bandgap material

In this paper, an electromagnetic bandgap (EBG) material in the range of 0.5–0.8 THz has been simulated with Arlon AR 600 (ε=6.0) as host material and air‐cylinders as the foreign embedded material. The effective dielectric permittivity of this material has been analyzed at the frequency range of 0.590–0.620 THz. The reduced effective dielectric permittivity substrate of thickness 50 µm has been used to design the microstrip antenna at 600 GHz with a novel approach. This proposed antenna shows an enhanced directivity of 15.1 dBi at 600 GHz frequency. To compare the analysis, the operating frequency has been scaled down by a factor of 100 and various results have been compared by using two different commercially available simulators CST Microwave Studio based on the finite integral technique and Ansoft HFSS based on the finite element method. Copyright © 2010 John Wiley & Sons, Ltd.     

A novel electronic micro-viscometer

Microsystem Technologies - This paper reports the development of a novel electronic micro-viscometer capable of measuring viscosity of different Newtonian fluids using less than 100 µl which...     

The stochastic aeroelastic response analysis of helicopter rotors using deep and shallow machine learning

Neural Computing and Applications - This paper addresses the influence of manufacturing variability of a helicopter rotor blade on its aeroelastic responses. An aeroelastic analysis using finite...     

Structurally Diverse Histone Deacetylase Photoreactive Probes: Design,Synthesis, and Photolabeling Studies in Live Cells and Tissue

Histone deacetylase (HDAC) activity is modulated in vivo by post-translational modifications and formation of multiprotein complexes. Novel chemical tools to study how these factors affect engagement of HDAC isoforms by HDAC inhibitors (HDACi) in cells and tissues are needed. In this study, a synthetic strategy to access chemically diverse photoreactive probes (PRPs) was developed and used to prepare seven novel HDAC PRPs 9 – 15 . The class I HDAC isoform engagement by PRPs was determined in biochemical assays and photolabeling experiments in live SET-2, HepG2, HuH7, and HEK293T cell lines and in mouse liver tissue. Unlike the HDAC protein abundance and biochemical activity against recombinant HDACs, the chemotype of the PRPs and the type of cells were key in defining the engagement of HDAC isoforms in live cells. Our findings suggest that engagement of HDAC isoforms by HDACi in vivo may be substantially modulated in a cell- and tissue-type-dependent manner.     

Bandwidth Enhancement of a Wide Slot Antenna Using Fractal Geometry for UWB Application with Multiple Notched Bands

Wireless Personal Communications - In this paper a combination of rectangular and elliptical fractal geometry is applied on a regular hexagonal wide slot antenna fabricated using a FR4 substrate to...     

Clock Distribution Methodology for PowerPC? Microprocessors

Clock distribution design for high performance microprocessors has become increasingly challenging in recent years. Design goals of state-of-the-art integrated circuits, dictate the need for clock networks with smaller skew tolerances, large sizes, and lower capacitances. In this paper we discuss some of the issues in clock network design that arise in this context. We describe the clock design methodology and techniques used in the design of clock distribution networks for PowerPC microprocessors that aim at alleviating some of these problems.     

High Performance Lithium‐Ion Batteries Using Layered 2H‐MoTe2 as Anode

The major challenges faced by candidate electrode materials in lithium‐ion batteries (LIBs) include their low electronic and ionic conductivities. 2D van der Waals materials with good electronic conductivity and weak interlayer interaction have been intensively studied in the electrochemical processes involving ion migrations. In particular, molybdenum ditelluride (MoTe₂) has emerged as a new material for energy storage applications. Though 2H‐MoTe₂ with hexagonal semiconducting phase is expected to facilitate more efficient ion insertion/deinsertion than the monoclinic semi‐metallic phase, its application as an anode in LIB has been elusive. Here, 2H‐MoTe₂, prepared by a solid‐state synthesis route, has been employed as an efficient anode with remarkable Li⁺ storage capacity. The as‐prepared 2H‐MoTe₂ electrodes exhibit an initial specific capacity of 432 mAh g^?1 and retain a high reversible specific capacity of 291 mAh g^?1 after 260 cycles at 1.0 A g^?1. Further, a full‐cell prototype is demonstrated by using 2H‐MoTe₂ anode with lithium cobalt oxide cathode, showing a high energy density of 454 Wh kg^?1 (based on the MoTe₂ mass) and capacity retention of 80% over 100 cycles. Synchrotron‐based in situ X‐ray absorption near‐edge structures have revealed the unique lithium reaction pathway and storage mechanism, which is supported by density functional theory based calculations.