Technical Study of a Standalone Photovoltaic–Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia

Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.     

Management of jute yellow mosaic virus disease through cultural practices

A field experiment was conducted to investigate the effect of some management practices to minimise jute yellow mosaic virus disease. The management practices were employed at natural condition and placed randomly with four replications. The treatments were spraying malathion 57 EC, rouging and field sanitation, top dressing of nitrogenous fertiliser, mulching with straw and untreated control. The highest percentage of mosaic incidence was recorded in control and the lowest incidence was recorded in top dressing of nitrogenous fertiliser. Among the treatments, top dressing of nitrogenous fertiliser showed the best performance in terms of increasing yield (3.05?t/ha). The second highest was obtained in rouging and field sanitation which was statistically similar to spraying malathion 57 EC. The best gross margin ($379.02/ha) and increase of gross margin (63.00%) compared to control were achieved in top dressing of nitrogenous fertiliser with the highest benefit-cost ratio (4.84). However, the treatments were found significantly profitable compared to the control indicating the usefulness of the cultural practices in integrated disease management programme for healthy and profitable jute cultivation.     

Pseudomonas aeruginosa FARP72 Offers Protection Against Aeromonas hydrophila Infection in Labeo rohita

Use of probiotics as the biocontrol agent for disease prevention in aquaculture is gaining importance as an alternative to the indiscriminate use of antibiotics and other chemotherapeutics. In view of this trend, the probiotic properties of a potent antagonistic bacterium, Pseudomonas aeruginosa FARP₇₂, was characterized in terms of safety, antagonistic activities, in vitro immunomodulation, and in vivo disease resistance. Immunomodulatory activity was ascertained by measuring the production of intracellular superoxide anion, nitric oxide, total leukocyte peroxidase content, and the leukocyte proliferation in head kidney leukocytes. The bacterium isolated from the skin mucus of freshwater catfish Clarias batrachus was harmless to Labeo rohita. It showed inhibitory activity against Aeromonas caviae, A. hydrophila, Edwardsiella tarda, Pseudomonas putida, and Streptococcus agalactiae as revealed by cross and parallel streaking methods. Significantly higher superoxide anion and nitric oxide production, peroxidase content, and proliferative responses of leucocytes delineated the strains’ ability to interact with immune cells to activate the immune system in vitro. Significant growth inhibition of A. hydrophila from 1.55 × 10⁵ CFU/mL was observed when co-cultured with P. aeruginosa FARP₇₂ in phosphate-buffered saline (PBS) at levels ranging from 2.61 × 10⁷ to 2.61 × 10⁹ CFU/mL in 10 days. P. aeruginosa FARP₇₂ increased the survival rate of rohu fingerlings against pathogenic A. hydrophila challenge in biocontrol study in vivo as determined by cohabitation challenge. These results suggest that P. aeruginosa FARP₇₂ is a potential probiotic strain and can be used in aquaculture to improve the health status and disease resistance of fish.

     

Blocking neddylation elicits antiviral effect against hepatitis B virus replication

Molecular Biology Reports - Hepatitis B Virus (HBV) is the most common cause of chronic liver disease worldwide. The mechanisms that regulate HBV viral replication remain poorly defined. Here, we...     

An Eye-Shaped Ultra-Sensitive Localized Surface Plasmon Resonance–Based Biochemical Sensor

Plasmonics - This research illustrates a parametric study based on surface plasmon resonance of a slightly gold-coated photonic crystal fiber (PCF). In verifying sensing accuracy, the proposed...     

DisPredict: A Predictor of Disordered Protein Using Optimized RBF Kernel

Intrinsically disordered proteins or, regions perform important biological functions through their dynamic conformations during binding. Thus accurate identification of these disordered regions have significant implications in proper annotation of function, induced fold prediction and drug design to combat critical diseases. We introduce DisPredict, a disorder predictor that employs a single support vector machine with RBF kernel and novel features for reliable characterization of protein structure. DisPredict yields effective performance. In addition to 10-fold cross validation, training and testing of DisPredict was conducted with independent test datasets. The results were consistent with both the training and test error minimal. The use of multiple data sources, makes the predictor generic. The datasets used in developing the model include disordered regions of various length which are categorized as short and long having different compositions, different types of disorder, ranging from fully to partially disordered regions as well as completely ordered regions. Through comparison with other state of the art approaches and case studies, DisPredict is found to be a useful tool with competitive performance. DisPredict is available at https://github.com/tamjidul/DisPredict_v1.0.     

Development and calibration of bio-kinetic model for surfactant biodegradation with combined respirometric and titrimetric measurements

Substrate removal mechanism in aerobic activated sludge processes was lately modeled using the simultaneous storage and growth (SSAG) phenomenon. The SSAG model was further refined with titrimetric components and successfully calibrated using both respirometric and titrimetric measurements for common substrate acetate. However, the improved SSAG model calibration was not verified with other organic substrates. Furthermore, very few studies are available in the literature on surfactant bio-kinetics, which generally use off-line experimental measurements with limited model-based interpretation. Therefore, the aim of this paper is to demonstrate its applicability for surfactant biodegradation using on-line measurements. Batch experiments were conducted using sodium dodecyl sulfate (SDS) as a test surfactant. Model calibration was done successfully for three different SDS concentrations using respirometric, titrimetric and combined respirometric-titrimetric measurement approaches. The parameter estimation results from all three stated combinations were statistically evaluated and found to be very close validating the model.     

Antimicrobial Resistance,Virulence Factors and Genetic Diversity of Escherichia coli Isolates from Household Water Supply in Dhaka,Bangladesh

Background

Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity.

Methodology/Principal Findings

A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84) of the isolates were multi-drug(≥3 classes of antibiotics) resistant (MDR) and 26% (n = 22) of these were positive for extended spectrum β-lactamase (ESBL). Of the 22 ESBL-producers, 20 were positive for bla _CTX-M-15, 7 for bla _OXA-1-group (all had bla _OXA-47) and 2 for bla _CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16) of the isolates carried virulence gene(s) characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8) of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates.

Significance

Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in urban areas.     

Connectivity of Tiger (Panthera tigris) Populations in the Human-Influenced Forest Mosaic of Central India

Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km) between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent.