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An analytical methodology for the fast separation and determination of iodophenol species in natural water samples was developed using capillary electrophoresis (CE) coupled to inductively coupled plasma-mass spectrometry (ICP-MS). Based on the element-specific and highly sensitive detection provided by ICP-MS, the methodology has been applied to the analysis of 2-iodophenol, 4-iodophenol, and 2,4,6-triiodophenol. The use of solid-phase microextraction (SPME), after proper optimization, improved the signal by a factor of 100 leading to detection limits in the sub microg.L(-1). Different desorption conditions of iodophenol compounds from the SPME microfiber were studied to achieve the optimum preconcentration factor and best analytical performance. Different CE conditions were studied to achieve complete baseline separation of iodophenols in short migration times. Three different CE buffer systems were evaluated using ICP-MS detection. A buffer solution containing 20 mmol.L(-1) 3-(cyclohexylamino)-1-propanesulfonic acid (CAPS) and an applied potential of +22 kV were finally selected leading to a maximum separation time of 6.6 min. A relative standard deviation (%RSD) of about 5.0% for ten consecutive determinations was obtained. Finally, the speciation methodology developed was utilized for the determination of iodophenol compounds in natural water samples.

This contribution considers various aspects of a quasi direct current, convoluted arc produced by a magnetic field (B-field) connected in parallel with an RLC circuit that have not been considered in combination. These aspects are the arc current limitation due to the arc convolution, changes in arc resistance due to the B-field and material ablation, and the relative significance of the RLC circuit in producing an artificial current zero. As a result, it has been possible to produce an empirical equation for predicting the current interruption capability in terms of the B-field magnitude and RLC components.

The number of subjects to be offered for GCE (Advanced Level)examination for university admission in Sri Lanka is going to be reduced to three from the four subjects required at present. That means, one subject has to be dropped from the present set of subjects. There has been a debate regarding which subject should to be dropped. At the same time, a set of new subjects are being introduced and revision of syllabi are also taking place. This article tries to critically analyse the impact of the proposed innovations with respect to different possible decisions related to the admissions to the faculties of engineering in Sri Lanka.

Grid codes imposed by utilities regulate the operation of Voltage Source Converter - High Voltage Direct Current (VSC-HVDC) interconnected offshore wind farms. Fault ride-through (FRT) specifications require the adoption of specific measures to avoid over-voltages of the HVDC link during faults in order to protect the HVDC equipment. Implementing Energy Diverting Converters (EDC), for instance Dynamic Braking Resistor (DBR) circuits, at the DC link is an established method to comply with the grid codes, where the excess energy of the wind farm is diverted into the parallel circuit during the fault. In this paper an evaluation of three different state-of-the-art DBR circuits is performed in order to establish the advantages and disadvantages of each circuit. The evaluation has shown that although the three solutions meet the FRT requirements, the modular topologies generate reduced slope current and voltage step changes during their operation, while being larger in size and requiring a higher number of semiconductors as compared to the traditional DC chopper circuit employing hard switched series connected semiconductor arrangements.

This paper provides an overview of the Islamic banking system and its product ranges, and examines their ability to meet Corporate Social Responsibility obligations while maintaining efficiency and managing risk. The growing literature on Islamic banking products, including their derivatives indicates that Islamic banking is popular worldwide and has global attention. Similarly, the diversity of banking options is growing in Middle Eastern countries with some banks offering separate windows for conventional and Islamic banking options to customers. Due to the unique nature of Islamic banking, which is constrained not only by the standard operating regulations of the respective countries, but also by Islamic law, the Sharī’ah, there are significant differences in the philosophy behind its finance transactions, the nature of transactions, goals and the obligations between the two types of institutions. Whether these differences lead to changes in risk preferences, lending decision-making processes, and the ultimate efficiency of operations are some of the key empirical questions yet to be fully answered. The paper introduces a theory based on classical utility theory, and then extends it to show its relevance to Islamic banking. In particular this paper shows that Islamic banking may not only improve operating performance, but also increase profitability for all parties concerned.

Renal cell cancer (RCC) is not a single disease but is made up of a number of cancers, each with a unique histology, biology, clinical course and response to therapy. Alterations in at least 16 hereditary genes have been attributed to the risk of developing RCC. In this study, we describe the prevalence and spectrum of germline variants among these genes and highlight correlations between germline genotype with tumor phenotype. Using the Geisinger MyCode cohort, we sequenced the whole exomes of 42,933 subjects. Subjects were divided into those with a renal cancer diagnosis, other cancer diagnosis and no cancer diagnosis. We analyzed the DNA sequences of 16 hereditary renal cancer genes from each of these groups. The damaging mutations was determined by following ACMG guidelines. Among the 42,933 subjects in the Geisinger MyCode cohort, 168 were diagnosed with RCC. None of these subjects had a family history of RCC. Clear cell RCC (ccRCC) was the most predominant histology (77%), followed by Type 1 papillary RCC (7%), chromophobe RCC (6%), and Type 2 papillary RCC (5%). Mutations in all the predisposing genes were identified in all the renal cancer subtypes but only a subset were deemed damaging. The top 2 ccRCC predisposing genes with damaging or likely damaging mutations were TSC2 (8%) and SDHD (4%). While TSC2 damaging variants were also found in the other histologies, novel TSC2 variants were differentially associated with high grade and metastatic disease in ccRCC as compared to those with low grade or non-metastatic disease. The genes harboring damaging or likely damaging variants in Type 1 and Type 2 papillary RCC were MET and FH respectively. Predisposing RCC germline mutations were found in a significant number of subjects with sporadic RCC. Family history was unhelpful in predicting the affected subjects. Knowledge of these mutations would be beneficial in counseling patients and their families as well as improving our understanding of the disease to direct patient care. Citation Format: Heinric Williams, Raghu Metpally, Mahmoud Mohamed, Sarath Krishnamurthy, Sertac Kip, David J. Carey, Aris Baras, John Overton. Germline mutations in renal cancer predisposing genes: Analysis of the Geisinger MyCode population. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2557.

Desorption isotherm of fresh tea leaves was studied using static gravimetric method of saturated salt solutions at temperatures of 15, 20, 25 and 30ºC and water activities of 0.07 to 0.97. Data were fitted to five mathematical equations. Using the best-fit mathematical model, thermodynamic properties of fresh tea leaves including net isosteric heat of sorption, differential entropy were estimated. The applicability of enthalpy – entropy compensation theory for fresh tea leaves was also evaluated. Results showed that the modified Oswin model was best fitted with the experimental data. Thermodynamics properties like net isosteric heat of sorption and differential entropy were found to decrease exponentially with the increase in moisture content. Net isosteric heat of sorption and differential entropy increased exponentially with decreasing moisture content of fresh tea leaves. Isosteric heat of sorption of fresh tea leaves was very close to heat of vaporization of pure water when the moisture content of tea leaves exceeded 40% (d.b.). The enthalpy-entropy compensation theory could be successfully applied for the moisture desorption behavior of fresh tea leaf samples and it was enthalpy driven spontaneous process.

This paper describes a novel technique for interrupting direct currents (D.C.) with an electromagnetically convoluted arc in air at atmospheric pressure. Investigations are reported on the effects of using a separate current for producing the arc convolving electromagnetic field (B-field) to that being interrupted and using a separate R, L, C circuit in parallel with the arc contacts. Experimental results are presented for the time variation of currents flowing through the arc gap, the B-field coil and the parallel R, L, C circuit, along with the voltage across the arc gap.

The hog deer Axis porcinus was believed to be extinct in Sri Lanka until a recent preliminary survey revealed a single remaining population in a 35-sq-km area of the south-western coastal belt. The authors describe the results of their 3-month study, outline potential threats to the survival of the population and discuss possible conservation measures.

Presents a collection of slides that discuss the following: power electronic; reactive power compensators; shunt compensation; series compensation; HVDC transmission technology; power flow; wind energy system and power system stability and grid connection of renewable sources.

The analysis of the reactive power management of a wind farm consisting of fixed speed wind turbines is carried out. The rating calculation of the compensator for a fixed speed wind farm is evaluated, and the effect of the network strength on the compensator rating is studied. Also the compatibility of fixed speed wind turbine with the new UK grid code requirements is evaluated by simulation using Matlab/Simulink. The simulation results show that the compensator rating is mainly determined by the need to meet the grid code specifications, rather than the steady state reactive power capability obligation. The main conclusion is that a fixed speed wind farm based on simple induction generators is unable to meet the new grid code requirements, unless the compensator rating is increased substantially.

The service maintenance of a 3-phase induction motor is limited when compared with other types of motors. The overhaul process needs to be developed to ensure that the motor will perform in service without failure. This is achieved by undertaking a number of tests and examinations, as part of the overhaul operation to guarantee the reliability of he motor. This paper reviews a number of tests that have been developed, as part of the overhaul processes on the 3 phase induction motor to improve it's in service reliability. This paper will also explore the areas that have been found to be problematic.

Levels of (−)-epicatechin in tea cultivars resistant to blister blight leaf disease were significantly higher than those in susceptible cultivars, while the reverse was true for (−)-epigallocatechin gallate, suggesting that epicatechin was involved in the resistance mechanism. The content of the methylxanthines, caffeine and theobromine, in the leaf increased in the initial translucent stage of the disease, probably as a defense response to fungal attack. Epicatechin and epigallocatechin levels were less than in healthy tissues at this stage, but increases in the corresponding gallate esters suggested that they were being converted into esters. Although epicatechin and epigallocatechin levels decreased from translucent to mature blister stages, the decrease was not significant. The decrease in levels of epicatechin, epigallocatechin, and their esters on infection and the formation of cyanidin and delphinidin on oxidative depolymerization of the blisters suggests that proanthocyanidins may play a role in the defense mechanism. The high resistance of a purple green leafed cultivar is attributed to the additional catechin source provided by the high levels of anthocyanins present.

Enzyme engineering was performed to link the β-glucosidase enzyme (BGL1) from Saccharomycopsis fibuligera to the cellulose-binding domain (CBD2) of Trichoderma reesei cellobiohydrolase (CBHII) to investigate the effect of a fungal CBD on the enzymatic characteristics of this non-cellulolytic yeast enzyme. Recombinant enzymes were constructed with single and double copies of CBD2 fused at the N-terminus of BGL1 to mimic the two-domain organization displayed by cellulolytic enzymes in nature. The engineered S. fibuligera β-glucosidases were expressed in Saccharomyces cerevisiae under the control of phosphoglycerate-kinase-1 promoter (PGK1 P ) and terminator (PGK1 T ) and yeast mating pheromone α-factor secretion signal (MFα1 S ). The secreted enzymes were purified and characterized using a range of cellulosic and non-cellulosic substrates to illustrate the effect of the CBD on their enzymatic activity. The results indicated that the recombinant enzymes of BGL1 displayed a 2–4-fold increase in their hydrolytic activity toward cellulosic substrates like avicel, amorphous cellulose, bacterial microcrystalline cellulose, and carboxy methyl cellulose in comparison with the native enzyme. The organization of the CBD in these recombinant enzymes also resulted in enhanced substrate affinity, molecular flexibility and synergistic activity, thereby improving the ability of the enzymes to act on and hydrolyze cellulosic substrates, as characterized by adsorption, kinetics, thermal stability, and scanning electron microscopic analyses.

Energy saving motor controllers for refrigeration and air-conditioning applications operate at the minimum input power point by finding the optimum firing angle of the thyristors in the motor controller. Consequently, the distorted input current contains harmonics, sub-harmonics, and interharmonics whose frequencies change with the motor speed. Therefore passive filters are not suitable and the best solution is to use an active filter. A single phase active filter with simple constant frequency switching is able to reduce waveform distortion by eliminating a sufficient range of frequencies and offers a low cost solution. Theoretical analysis of the full-bridge and half-bridge topologies led to the development of design equations and curves. Simulation of a half-bridge active filter confirmed the design equations

Infection of leaves of tea (Camellia sinensis (Kuntze) L, cv TRI 2025) which was susceptible to blister blight (Exobasidium vexans Massee), resulted in a shift of the proanthocyanidin stereochemistry away from 2,3-trans (e.g. catechin and gallocatechin) and towards 2,3-cis (e.g. epicatechin and epigallocatechin). Infection also resulted in increased gallic acid esterification of the initiating subunits of proanthocyanidins. This was shown by both mass spectroscopy and phloroglucinolysis. Proanthocyanidins isolated from healthy tissue had a predominantly 2,3-trans stereochemistry which accounted for 53% and 61% of the total initiating and extension units of proanthocyanidin, respectively. Conversely in infected tissue, proanthocyanidin subunits with a 2,3-trans stereochemistry accounted for 26% and 40% of the total initiating and extension units, respectively. Infection had little impact on the hydroxylation state of the B-rings of proanthocyanidins. The products of acid hydrolysis under oxidative conditions had a slight excess of di-hydroxylated B-rings with cyanidin accounting for 58.3+/-0.05% and 60.4+/-0.2% of the total anthocyanidin recovered following hydrolysis of proanthocyanidin isolated from infected and healthy leaves, respectively. Similar results were obtained by phloroglucinolysis.

γ-Aminobutyric acid (GABA), an important bioactive component of tea, acts as a major inhibitory neurotransmitter and is considered to influence other physiological processes in human as well as in planta. In the hereby presented study, the content of this valuable metabolite was investigated in two novel types of Ceylon Tea, explicitly “Silver Tips” and “White Tea”, originating from minimally processed buds of the unique cultivar, “TRI 2043″. The samples were subjected to hot water infusion, equivalent to the traditional beverage preparation procedure, and analyzed by means of hydrophilic interaction ultra performance liquid chromatography coupled to tandem mass spectrometry (HILIC LC-MS/MS). The registered GABA levels were compared with those obtained for the classic “Black Tea” and “Green Tea” samples from Sri Lanka. A high variation of GABA content was observed among the different tea types, especially in the case of “Silver Tips” and “White Tea”, indicating the crucial influence of the manufacturing procedure (processing extent) on the final abundance of the bioactive component of interest. Furthermore, “White Tea” samples boasted the highest GABA concentration reported for this type of tea so far, reaching up to 50% of that characteristic of the high-priced “GABA Tea”. Therefore, “White Tea” and “Silver Tips” were proved to be high quality teas with amounts of γ-aminobutyric acid comparable with those described for similar types before. To our knowledge, this is the first report on HILIC LC-MS/MS application for the quantification of GABA and for in-depth characterization of teas from Sri Lanka.

This paper presents a new fault detection technique for the diagnosis and localization of sub-module faults that are developed due to failures in switching devices inside Modular Multilevel Converters (MMC). Unlike other fault detection strategies that have been proposed in literature, the proposed fault detection technique does not need extra sensors or special power circuits as it depends on an ADAptive LINEar Neuron (ADALINE) capacitor voltage estimation algorithm. The proposed fault detection technique is validated by Hardware In the Loop (HIL) real time simulations through which different case studies are simulated to test the algorithm under different operating conditions.