Volume 20 Year 2016

Novel member of Ras family proteins from Disk Abalone (Haliotis discus discus): Structural profiling and its transcriptional modulation under host pathologic conditions

Fri, 01 Jan 2016 00:00:00 GMT

Novel member of Ras family proteins from Disk Abalone (Haliotis discus discus): Structural profiling and its transcriptional modulation under host pathologic conditions Elvitigala, D. A. S.; Premachandra, H. K. A; Wan, Q.; Lim, B.; Jung, H.; Choi, C. Y.; Lee, J. Among small GTPases, the Ras family proteins capture a remarkable place in dictating cellular proliferation, differentiation and survival in development of an organism. Major members of the Ras family include Ras (H-Ras, K-Ras, N-Ras), Rap1, and Rap2, all of which can act as oncogenes upon mutation. In the present study, a novel Ras family protein (AbRFP) was characterized from Disk Abalone (Haliotis discus discus), an economically important, edible marine gastropod; further analyzing its transcriptional profile in healthy and immune-challenged animals. The full-length cDNA of AbRFP is 2704 bp and it consists of an open reading frame of 552 bp, encoding a 184 amino acid peptide with a calculated molecular mass of ~21 kDa and isoelectric point of 8.63. The amino acid sequence resembles the characteristic features of typical Ras family proteins, including GTP/Mg2+ binding sites and guanine nucleotide exchange factor (GEF) interaction sites, as predicted by the NCBI-conserved domain database server. Phylogenetic study of AbRFP showed the generally accepted relationships, with AbRFP exhibiting highest proximity to a Ras protein from Portuguese oyster. Quantitative realtime PCR detected ubiquitous AbRFP mRNA expression, with strongest levels in muscle along with mantle and the lowest level in hepatopancreas. The AbRFP transcriptional profile in gills of Abalone challenged with Vibrio parahaemolyticus or viral hemorrhagic septicemia virus (VHSV) demonstrated significant up-regulations (p < 0.05) at 12 h and 24 h post-injection (p.i.), respectively. Moreover, significant elevation (p < 0.05) of mRNA expression was detected in hemocytes at 72 h p.i. with V. parahaemolyticus. These findings suggest that AbRFP may play a role under pathological conditions in Disk Abalone.

Towards a Steady State Economy in Sri Lanka

Fri, 01 Jan 2016 00:00:00 GMT

Towards a Steady State Economy in Sri Lanka Wijeratne, A. T.; Dias, P.; Adhikari, N. In general, it is desired that Sri Lankan economy shows growth. A growing economy brings waste production which leads environmental pollutions such as air pollution water pollution etc. At present, increasing population in Sri Lanka requires more natural resources to meet the market demand. The ultimate result is an imbalance in the biological cycles, and an irreversible change in both economic process and environment. An irreversible economic process increases entropy. Ultimately, the entropy will reach its maximum value. Then everything will become standstill since there would not exist more energy to continue the economic process. As a solution, the concept of a steady state economy is structured.Sri Lankan economy was assessed within steady state economics to evaluate the present economic situation of Sri Lanka. A statistical analysis was carried out on Gross Domestic Product (GDP), population, energy use, CO2 emission through time series analysis and regression analysis,to identify the extent to which Sri Lankan economy has deviated from a steady state economy. Regression analysis indicates a strong relationship between GDP and CO2 emission. Total population size in Sri Lanka is increased from 9.9 million in 1960 to 20.48 million in 2013. CO2 emission per capita is increased from 0.25 metric tons in 1960 to 0.65 metric tons in 2010. CO2 emission is increased from 2259 kiloton in 1960 to 12831 kiloton in 2010. Rapid growth rates, CO2 emissions, population growth rates reveal that Sri Lankan economy is far apart from the concept of steady state.Transition to a steady state economy would require the implementation of new policies to restrict the utilization of nonrenewable resources. On the other hand it is mandatory to have legal regulations encouraging renewable resource use, energy efficiency, and reuse and recycling.

Nucleotide Sequence and Secondary Structure Variations in ITS2-rDNA Region of the Members of Anopheles culicifacies (Diptera: Culicidae) Species Complex

Fri, 01 Jan 2016 00:00:00 GMT

Nucleotide Sequence and Secondary Structure Variations in ITS2-rDNA Region of the Members of Anopheles culicifacies (Diptera: Culicidae) Species Complex Shanika, K.H.S.; Harischandra, I.N.; De Silva, B.G.D.N.K. Anopheles culicifacies, major vector of malaria in Sri Lanka is a five member species complex. Differences of the vector competence of siblings, is still poorly delineated. Therefore, the current study was carried out to observe any relationship of the variations in vector competence to ITS2 nucleotide sequences and secondary structure characteristics of the species complex. DNA was extracted from sibling species B and E, the ITS2 region was amplified and sequenced. Sequences for A, C and D siblings were retrieved from NCBI GenBank. The complex divided into two groups, AD and BCE based on primary and secondary structure of the ITS2 sequences. Secondary structures of all species had three helices where pyrimidine-pyrimidine mismatch in Helix II and a UUUGG motif at 5‘ of Helix III were displayed only for B, C and E. Among five types of loops, interior and exterior loops were more conserved than other loop types. Results showed the major vector sibling E and poor or non vector sibling B shares identical nucleotide sequence and secondary structure. Therefore, ITS2 secondary structure is independent of the vector competence of the sibling species.

Android Application: Sound Pressure Level Meter and Frequency Spectrum Analyzer

Fri, 01 Jan 2016 00:00:00 GMT

Android Application: Sound Pressure Level Meter and Frequency Spectrum Analyzer Bandara, N. D. N. C.; Wanniarachchi, W. K. I. L. In this paper we present the development of Sound Pressure Level Meter and Frequency Spectrum Analyzer application for Android based devices. The developed application can visualize real time waveform and frequency spectrum of an input audio signal in both linear and dB scale. The GPS location, current date and time are also embedded to the application for convenience. A comparison was carried out with currently available smartphone apps of similar type and the results are in good agreement with the app developed in this project. The current version of the app is capable of capturing signal of maximum frequency up to 4000Hz. Therefore, analysis of frequency spectrum of the voice transmission which range between 300Hz to 3400Hz can be carried out successfully.