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We have synthesised blue (D-Blue), green (D-Green), and red (D-Red) emissive solution-processable dendrimers featuring a bis-tridentate iridium(III) complex core for incorporation into monochrome and white organic light-emitting diodes (WOLEDs). The iridium(III) complex cores have a common dendronised bis[imidazolyl]phenyl ligand and different ancillary ligands to control the emission colour. The dendronised bis[imidazolyl]phenyl ligand has three first-generation biphenyl dendrons with t-butyl surface groups attached, with two of the dendrons projecting over the core of the dendrimer. The three dendrimers, D-Blue, D-Green, and D-Red had similar solution photoluminescence quantum yields (PLQYs) of around 75%. The neat film PLQYs were decreased relative to those in solution due to intermolecular interchromophore interactions. Blending the dendrimers at a concentration of 1 mol% with tris(4-carbazoyl-9-ylphenyl)amine (TCTA) increased the PLQYs but not to the level measured in solution (at best around 50% of the value), which was ascribed to the dendrimers and TCTA not forming a blend film in which the guest was evenly distributed in the host. Neat film monochrome three-layer devices had modest performance with maximum external quantum efficiencies (EQEs) of between 1.6% (red emission) and 5.3% (green emission). When the dendrimers were blended into TCTA at a concentration of 1 mol% the maximum EQEs of the monochrome OLEDs increased to 5.0%, 12%, and 8.3% for blue, green, and red emission, respectively. Host-free WOLEDs composed of a blend of D-Blue (95%), D-Green (2.5%), and D-Red (2.5%) in a single emissive layer had an EQE of 5.4%, which was higher than expected based on the monochrome device performance and was ascribed to D-Blue acting as a host for the emissive D-Green and D-Red. The optimised WOLED with the three dendrimers at a combined concentration of 1.0 mol% in TCTA had an EQE of 9.3%. Both the host-free and host-containing WOLED devices emitted a warm white. [ABSTRACT FROM AUTHOR]

Abstract On the Earth, the human body is designed and adapted to function under uniform gravitational acceleration. However, exposure to microgravity or weightlessness as experienced by astronauts in space causes significant alterations in the functioning of the human cardiovascular system. Due to limitations in using real microgravity platforms, researchers opted for various ground-based microgravity analogs including head-down tilt (HDT) at fixed inclination. However, in the present study, an investigation of response of various cardiac parameters and their circulatory adaptation in 18 healthy male subjects was undertaken by using an indigenously developed 360° rotating platform. Cardiac pulse was recorded from 0° to 360° in steps of 30° inclination using piezoelectric pulse sensor (MLT1010) and associated cardiac parameters were analyzed. The results showed significant changes in the pulse shape while an interesting oscillating pattern was observed in associated cardiac parameters when rotated from 0° to 360°. The response of cardiac parameters became normal after returning to supine posture indicating the ability of the cardiovascular system to reversibly adapt to the postural changes. The observed changes in cardiac parameters at an inclination of 270°, in particular, were found to be comparable with spaceflight studies. Based on the obtained results and the proposed extended version of fluid redistribution mechanism, we herewith hypothesize that the rotation of a subject to head down tilt inclination (270°) along with other inclinations could represent a better microgravity analog for understanding the cumulative cardiac response of astronauts in space, particularly for short duration space missions.

Fruit fly is one of the important insect pests of horticultural crops, both fruits and vegetables. After aphids, fruit fly was reported as a major insect problem in the plant clinic sessions from September 2013 to July 2016 in Nepal. The groups of horticultural crops most affected by fruit flies were cucurbitaceous vegetables, i.e. 79% of all fruit fly queries (bitter gourd, bottle gourd, chayote, cucumber, pumpkin, snake gourd, sponge gourd and squash) followed by fruits 14% (guava, sweet orange, mandarin, mango, peach, and pomegranate) and solanaceous vegetables 6% (brinjal, chillies and tomato). The fruit fly management measures, such as use of para-pheromone lure/traps, sanitation and cultural measures were mostly referred in plant clinics by plant doctors of Nepal. The availability of para-pheromone lures/traps as well as technical know-how of application focusing integrated management measures should be adopted to manage fruit fly in horticultural crops with the least disruption to the environment and human health. [ABSTRACT FROM AUTHOR]

Zirconium and hafnium oxides and silicates have emerged as potential replacements for SiO2 as gate dielectric material. Patterning of these materials by wet etching in fabrication areas originally designed for SiO2 gates may give rise to contamination of SiO2 by aqueous zirconium and hafnium species. This paper summarizes the work carried out to characterize the adsorption behavior of aqueous zirconium and hafnium species onto thermally grown silicon dioxide. Electrokinetic and adsorption measurements were carried out to understand the extent and nature of interaction. The adsorption of both Zr and Hf species showed a maximum at pH 5.5. Significant reduction in the adsorption of both Zr and Hf occurred upon addition of fluoride ions to the solution. Using appropriate speciation diagrams, an adsorption model has been developed to explain the experimental data. [ABSTRACT FROM AUTHOR]