A scalable constraint-based Q-hash indexing for moving objects

In this paper, we develop a Q-hash index structure to efficiently store the position of moving objects. An environment of moving objects contains continuously changing locations which are hard to index using traditional index structures such as R-trees, QuadTrees and their variants. In order to answer the queries accurately, one of the problems faced in storing these positions is the number of updates that have to be made to the database whenever locations change. The high maintenance overhead on updates leads to performance degradation of these index structures; additionally, it makes the database very bulky which results in very poor performance in terms of query execution time. One of the main objectives of the structure we propose is to minimize the number of updates to the database to an optimal number so that the accuracy and response time of the query result are not compromised and at the same time the number of wireless communications can be reduced. The indexing is done using a hashing technique where the hashing function makes use of a region based QuadTree structure. To improve the efficiency of the query processing our index structure helps us define constraints over speed, direction and location of the moving object at the device level which controls the number of updates. In addition, in order to answer different query types efficiently at all levels we propose a three-tier (moving object, regional server, central repository) architecture. Our extensive performance evaluation and comparison of the proposed technique concludes that our scheme outperforms existing Q + R-tree and QuadTree in terms of range query execution time by a high order of magnitude.     

In vitro hydrolysis of plant protein concentrate with papain

A method was tested for measuring in vitro papain proteolysis of extracted plant protein to products soluble in trichloroacetic acid. The effects of incubation time, temperature and enzyme concentration were examined. Maximum proteolysis (82.9%) was obtained at 70°C for 24 h and a ratio of papain/protein substrate of approximately 1:10.     

A Novel Graphene Conductive Ink Based Circular Patch Antenna for 2.4 GHz Application

Graphene conductive ink based microstrip line fed circular patch is presented in this paper. The main objective of this work is to replace copper with graphene which is an emerging promising material, in the field of patch antennas with conventional rigid substrates using a simple printing technique and to measure its performance. The prototyped screen printed graphene antenna is perfectly radiating and the return loss, VSWR and gain of the graphene antenna is found to be better than conventional copper antenna. Also, the bandwidth of the graphene antenna is 1.6 times greater than that of the conventional copper antenna on rigid substrate.

     

Ethylene Production and Peroxidase Activity in Aphid-Infested Barley

The purpose of this work was to investigate whether ethylene is involved in the oxidative and defensive responses of barley to the aphids Schizaphis graminum (biotype C) and Rhopalophum padi. The effect of aphid infestation on ethylene production was measured in two barley cultivars (Frontera and Aramir) that differ in their susceptibility to aphids. Ethylene evolution was higher in plants infested for 16 hr than in plants infested for 4 hr in both cultivars. Under aphid infestation, the production of ethylene was higher in cv. Frontera than in Aramir, the more aphid susceptible cultivar. Ethylene production also increases with the degree of infestation. Maximum ethylene evolution was detected after 16 hr when plants were infested with 10 or more aphids. Comparing the two species of aphids, Schizaphis graminum induced more ethylene evolution than Rhopalosiphum padi. Infestation with S. graminum increased hydrogen peroxide content and total soluble peroxidase activity in cv. Frontera, with a maximum level of H₂O₂ observed after 20 min of infestation and the maximum in soluble peroxidase activity after 30 min of infestation. When noninfested barley seedlings from cv. Frontera were exposed to ethylene, an increase in hydrogen peroxide and in total peroxidase activity was detected at levels similar to those of infested plants from cv. Frontera. When noninfested plants were treated with 40 ppm of ethylene, the maximum levels of H₂O₂ and soluble peroxidase activity were at 10 and 40 min, respectively. Ethylene also increased the activity of both cell-wall-bound peroxidases types (ionically and covalently bound), comparable with infestation. These results suggest that ethylene is involved in the oxidative responses of barley plants induced by infestation.     

Evaluation of the nutritive value of plant protein concentrates

The nutritive value of acid and steam precipitated plant proteins extracted at pH 11 and acid precipitated plant proteins extracted at pH 8–11 were estimated. Acid precipitation was found to result in a higher true protein digestibility, biological value, net protein utilisation and protein efficiency ratio in rats and to be more completely hydrolysed in vitro than steam precipitated proteins. Proteins extracted from leaves at pH 11 were superior, for the same nutritive characteristics, to proteins extracted at lower pH (8–10) values. These differences are discussed in terms of differences in the quantities of certain amino acids present in the proteins, structural changes in the proteins and protein-carbohydrate interactions.     

An improved technique for plant protein extraction

Studies on the extractability of plant protein showed that solubilisation of protein from plants harvested at different stages of growth before flowering depended on the water content of the macerated plant material and the level of alkalinity. Solubilisation increased as the pH value was raised from 6.2 to 11.00 by addition of NaOH solution and as the dry matter content decreased from 90 to 37.5 g/kg of mixture by water dilution. A dry matter concentration of 45 g/kg and pH 11 were adopted as most suitable extraction conditions which allowed 82-86% nitrogen yield from the five plant species tested. Ageing of plants had an adverse effect on nitrogen extractability. Of the total extractable nitrogen, the true protein nitrogen content increased with age up to commencement of flowering but once flowering had commenced the content was lower.